Removed go.mod, go.sum

Bump version to v0.9.11
Update 'README.md'
2024-08-14 10:26:42 +00:00 · 2024-07-15 02:06:26 -07:00 · 2024-05-02 00:48:50 -07:00 · 2024-05-01 23:58:44 -07:00 · 2024-05-01 23:49:36 -07:00 · 2024-05-01 23:48:18 -07:00
44 changed files with 3576 additions and 1373 deletions
--- a/.golangci.yml
+++ b/.golangci.yml
@ -0,0 +1,160 @@
+linters-settings:
+  depguard:
+    list-type: blacklist
+    packages:
+      # logging is allowed only by logutils.Log, logrus
+      # is allowed to use only in logutils package
+      - github.com/sirupsen/logrus
+    packages-with-error-message:
+      - github.com/sirupsen/logrus: "logging is allowed only by logutils.Log"
+  dupl:
+    threshold: 125
+  funlen:
+    lines: 125
+    statements: 50
+  gci:
+    local-prefixes: github.com/golangci/golangci-lint
+  goconst:
+    min-len: 2
+    min-occurrences: 2
+  gocritic:
+    enabled-tags:
+      - diagnostic
+      - experimental
+      - performance
+      #- style
+      #- opinionated
+    disabled-checks:
+      - commentFormatting
+      - commentedOutCode
+      - dupImport # https://github.com/go-critic/go-critic/issues/845
+      - ifElseChain
+      - octalLiteral
+      - whyNoLint
+      - wrapperFunc
+  gocyclo:
+    min-complexity: 15
+  goimports:
+    local-prefixes: github.com/golangci/golangci-lint
+  gomnd:
+    settings:
+      mnd:
+        # don't include the "operation" and "assign"
+        checks: argument,case,condition,return
+  govet:
+    check-shadowing: true
+    settings:
+      printf:
+        funcs:
+          - (github.com/golangci/golangci-lint/pkg/logutils.Log).Infof
+          - (github.com/golangci/golangci-lint/pkg/logutils.Log).Warnf
+          - (github.com/golangci/golangci-lint/pkg/logutils.Log).Errorf
+          - (github.com/golangci/golangci-lint/pkg/logutils.Log).Fatalf
+  lll:
+    line-length: 140
+  maligned:
+    suggest-new: true
+  misspell:
+    locale: en_CA
+  nolintlint:
+    allow-leading-space: true # don't require machine-readable nolint directives (i.e. with no leading space)
+    allow-unused: false # report any unused nolint directives
+    require-explanation: false # don't require an explanation for nolint directives
+    require-specific: false # don't require nolint directives to be specific about which linter is being skipped
+
+linters:
+  # please, do not use `enable-all`: it's deprecated and will be removed soon.
+  # inverted configuration with `enable-all` and `disable` is not scalable during updates of golangci-lint
+  disable-all: true
+  enable:
+    - bodyclose
+    - depguard
+    - dogsled
+    - dupl
+    - errcheck
+    - exhaustive
+    - exportloopref
+    - funlen
+    - gochecknoinits
+    - goconst
+    - gocritic
+    - gocyclo
+    - gofmt
+    - goimports
+    #- golint
+    - gomnd
+    - goprintffuncname
+    - gosec
+    - gosimple
+    - govet
+    - ineffassign
+    #- interfacer
+    - lll
+    - misspell
+    #- nakedret
+    - noctx
+    - nolintlint
+    - rowserrcheck
+    #- scopelint
+    - staticcheck
+    #- structcheck
+    - stylecheck
+    - typecheck
+    - unconvert
+    - unparam
+    - unused
+    #- varcheck
+    - whitespace
+
+  # don't enable:
+  # - asciicheck
+  # - deadcode
+  # - gochecknoglobals
+  # - gocognit
+  # - godot
+  # - godox
+  # - goerr113
+  # - golint
+  # - interfacer
+  # - maligned
+  # - nestif
+  # - prealloc
+  ## - rowserrcheck
+  # - scopelint
+  # - structcheck
+  # - testpackage
+  # - varcheck
+  # - wsl
+
+issues:
+  # Excluding configuration per-path, per-linter, per-text and per-source
+  exclude-rules:
+    - path: _test\.go
+      linters:
+        - gomnd
+
+    # https://github.com/go-critic/go-critic/issues/926
+    - linters:
+        - gocritic
+      text: "unnecessaryDefer:"
+
+    # TODO temporary rule, must be removed
+    # seems related to v0.34.1, but I was not able to reproduce locally,
+    # I was also not able to reproduce in the CI of a fork,
+    # only the golangci-lint CI seems to be affected by this invalid analysis.
+    - path: pkg/golinters/scopelint.go
+      text: 'directive `//nolint:interfacer` is unused for linter interfacer'
+
+run:
+  skip-dirs:
+    - test/testdata_etc
+    - internal/cache
+    - internal/renameio
+    - internal/robustio
+
+# golangci.com configuration
+# https://github.com/golangci/golangci/wiki/Configuration
+service:
+  golangci-lint-version: 1.23.x # use the fixed version to not introduce new linters unexpectedly
+  prepare:
+    - echo "here I can run custom commands, but no preparation needed for this repo"
--- a/CODE_OF_CONDUCT.md
+++ b/CODE_OF_CONDUCT.md
@ -55,5 +55,7 @@ to the project. Any intent to deviate the project from its original purpose
 of existence will constitute grounds for remedial action which may include
 expulsion from the project.

-This document is based upon the Code of Merit version 1.0 (Dec 4 2018).
+This document is based upon the original Code of Merit version 1.0 (Dec 4 2018).
 (https://web.archive.org/web/20181204203029/http://code-of-merit.org/)
+
+Updated version (Mar 29 2020): https://codeofmerit.org/code/
--- a/LICENSE.mit
+++ b/LICENSE.mit
@ -1,6 +1,6 @@
 MIT License

-Copyright (c) 2017 - 2019 Russell Magee (xs/xsd/xsnet/xspasswd)
+Copyright (c) 2017 - 2021 Russell Magee (xs/xsd/xsnet/xspasswd)

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
--- a/115
+++ b/115
@ -1,24 +1,60 @@
-.PHONY: lint vis clean common client server passwd subpkgs install uninstall reinstall
+VERSION := 0.9.11
+.PHONY: lint vis clean common client server passwd\
+ subpkgs install uninstall reinstall scc
+ 
+## Tag version of binaries with build info wrt.
+## GO111MODULE(=on) and vendor/ setup vs. $GOPATH pkg builds
+############################################################
+ifeq ($(shell go env GOMOD),)
+MTAG=
+else
+MTAG="-m"
+endif

-#ifeq ($(MAKEOPTS),)
-  MAKEOPTS = $(MAKEOPTS)
-#endif
+# If available, one may build 'garbled' binaries
+# See https://github.com/burrowers/garble.git
+ifeq ($(GARBLE),y)
+GO=garble -literals -tiny -debugdir=garbled
+else
+GO=go
+endif
+
+ifneq ($(VENDOR),)
+GOBUILDOPTS :=-v -mod vendor
+VTAG = "-v"
+else
+GOBUILDOPTS=
+VTAG =
+endif
+############################################################

 GIT_COMMIT := $(shell git rev-list -1 HEAD)
-VERSION := 0.8.9
+
 #ifeq ($(BUILDOPTS),)
-BUILDOPTS :=$(BUILDOPTS)" -ldflags \"-X main.version=$(VERSION) -X main.gitCommit=$(GIT_COMMIT)\""
+BUILDOPTS :=$(BUILDOPTS)"$(GOBUILDOPTS) -ldflags \"-X main.version=$(VERSION)$(MTAG)$(VTAG) -X main.gitCommit=$(GIT_COMMIT)\""
 #endif

 SUBPKGS = logger spinsult xsnet
-TOOLS = xspasswd xs xsd
+TOOLS = xs xsd
 SUBDIRS = $(LIBS) $(TOOLS)

+ifeq ($(GOOS),)
+	GOOS=$(shell go env GOOS)
+endif
+
+ifeq ($(GOOS),windows)
+ifeq ($(MSYSTEM),MSYS)
+WIN_MSYS=1
+endif
+endif
+
+
 INSTPREFIX = /usr/local

-all: common client server passwd
+all: common client server

 clean:
+	@echo "Make: $(MAKE)"
 	go clean .
 	for d in $(SUBDIRS); do\
 	  $(MAKE) -C $$d clean;\
@ -36,69 +72,56 @@ tools:


 common:
-	go build .
-	go install .
+	$(GO) build .
+	go install -a .


 client: common
 	$(MAKE) BUILDOPTS=$(BUILDOPTS) -C xs


-ifeq ($(MSYSTEM),)
-ifneq ($(GOOS),windows)
 server: common
+ifeq ($(MSYSTEM),MSYS)
+	echo "Build of xsd server for Windows not yet supported"
+else
 	$(MAKE) BUILDOPTS=$(BUILDOPTS) -C xsd
-else
-	echo "Cross-build of xsd server for Windows not yet supported"
-endif
-else
-server: common
-	echo "xsd server not (yet) supported on Windows"
 endif

-
-passwd: common
-	$(MAKE) BUILDOPTS=$(BUILDOPTS) -C xspasswd
+scc:
+	@scc --exclude-dir=bacillus,vendor,garbled --cocomo-project-type=rlabs,3,1.12,1,1

 vis:
 	@which go-callvis >/dev/null 2>&1; \
 	stat=$$?; if [ $$stat -ne "0" ]; then \
-	  /bin/echo "go-callvis not found. Run go get github.com/Russtopia/go-callvis to install."; \
+	  /bin/echo "go-callvis not found. Run go get https://github.com/TrueFurby/go-callvis to install."; \
 	else \
-	  make -C xs vis;\
-	  make -C xsd vis;\
-	  make -C xspasswd vis; \
+	  $(MAKE) -C xs vis;\
+	  $(MAKE) -C xsd vis;\
 	fi

 lint:
-	make -C xspasswd lint
-	make -C xsd lint
-	make -C xs lint
+	$(MAKE) -C xsd lint
+	$(MAKE) -C xs lint

 reinstall: uninstall install

 install:
-	cp xs/xs $(INSTPREFIX)/bin
-ifeq ($(MSYSTEM),)
-ifneq ($(GOOS),windows)
-	cp xsd/xsd xspasswd/xspasswd $(INSTPREFIX)/sbin
-else
-	mv $(INSTPREFIX)/bin/xs $(INSTPREFIX)/bin/_xs
+	echo "WIN_MSYS:" $(WIN_MSYS)
+ifdef WIN_MSYS
 	cp xs/mintty_wrapper.sh $(INSTPREFIX)/bin/xs
-	echo "Cross-build of xsd server for Windows not yet supported"
-endif
+	cp xs/mintty_wrapper.sh $(INSTPREFIX)/bin/xc
+	cp xs/xs $(INSTPREFIX)/bin/_xs
+	cp xs/xs $(INSTPREFIX)/bin/_xc
+	echo "Install of xsd server for Windows not yet supported"
 else
-	echo "Cross-build of xsd server for Windows not yet supported"
-endif
+	cp xs/xs $(INSTPREFIX)/bin
 	cd $(INSTPREFIX)/bin && ln -s xs xc && cd -
-
+	cp xsd/xsd $(INSTPREFIX)/sbin
+endif

 uninstall:
-	rm -f $(INSTPREFIX)/bin/xs $(INSTPREFIX)/bin/xc $(INSTPREFIX)/bin/_xs
-ifeq ($(MSYSTEM),)
-ifneq ($(GOOS),windows)
-	rm -f $(INSTPREFIX)/sbin/xsd $(INSTPREFIX)/sbin/xspasswd
-else
-endif
-else
+	rm -f $(INSTPREFIX)/bin/xs $(INSTPREFIX)/bin/xc \
+	$(INSTPREFIX)/bin/_xs $(INSTPREFIX)/bin/_xc
+ifndef $(WIN_MSYS)
+	rm -f $(INSTPREFIX)/sbin/xsd
 endif
--- a/README.md
+++ b/README.md
@ -1,12 +1,20 @@
 [![GoDoc](https://godoc.org/blitter.com/go/xs?status.svg)](https://godoc.org/blitter.com/go/xs)

-
 # XS
+
+![last build status](https://bacillus.blitter.com/onPush-xs-build/lastStatusIcon)
 --

-XS (**X**perimental **S**hell) is a golang implementation of a simple remote shell client and
-server, similar in role to ssh, offering encrypted interactive and non-interactive sessions,
-file copying and tunnels with traffic obfuscation ('chaffing').
+XS (**X**perimental **S**hell) is a simple alternative to ssh (<5% total SLOCC) written from scratch in Go.
+A testbed for candidate PQC (Post-Quantum Cryptography) KEMs (Key-Encapsulation Mechanisms) and symmetric
+session encryption algorithms.
+
+xs also features integrated traffic chaffing to obscure interactive session and file copy activity.
+Supports encrypted interactive and non-interactive sessions (remote commands), remote file copying and tunnels.
+
+Runs on Linux, FreeBSD, Windows (client only, MSYS) and Android (within Termux). https://gogs.blitter.com/RLabs/xs
+
+It is stable to the point that I use it for day-to-day remote access in place of, and in preference to, ssh.

 ***
 **NOTE: Due to the experimental nature of the KEX/KEM algorithms used, and the novelty of the overall codebase, this package SHOULD BE CONSIDERED EXTREMELY EXPERIMENTAL and USED WITH CAUTION. It DEFINITELY SHOULD NOT be used for any sensitive applications. USE AT YOUR OWN RISK. NEITHER WARRANTY NOR CLAIM OF FITNESS FOR PURPOSE IS EXPRESSED OR IMPLIED.**
@ -24,9 +32,9 @@ Currently supported exchanges are:

 * The HerraduraKEx key exchange algorithm first released at
 [Omar Elejandro Herrera Reyna's HerraduraKEx project](http://github.com/Caume/HerraduraKEx);
-* The KYBER IND-CCA-2 secure key encapsulation mechanism, [pq-crystals Kyber](https://pq-crystals.org/kyber/)  :: [Yawning/kyber golang implementation](https://git.schwanenlied.me/yawning/kyber)
-* The NEWHOPE algorithm [newhopecrypto.org](https://www.newhopecrypto.org/) :: [Yawning/go-newhope golang implementation](https://git.schwanenlied.me/yawning/newhope)
-
+* The KYBER IND-CCA-2 secure key encapsulation mechanism, [pq-crystals Kyber](https://pq-crystals.org/kyber/)  :: [Yawning/kyber golang implementation](https://gitlab.com/yawning/kyber)
+* The NEWHOPE algorithm [newhopecrypto.org](https://www.newhopecrypto.org/) :: [Yawning/newhope golang implementation](https://gitlab.com/yawning/newhope)
+* The FrodoKEM algorithm [frodokem.org](https://frodokem.org/) :: Go version by [Eduardo E. S. Riccardi](https://github.com/kuking/go-frodokem)

 Currently supported session algorithms:

@ -35,10 +43,27 @@ Currently supported session algorithms:
 * Twofish-128
 * Blowfish-64
 * CryptMTv1 (64bit) (https://eprint.iacr.org/2005/165.pdf)
+* ChaCha20 (https://github.com/aead/chacha20)
+* HOPSCOTCH (https://gogs.blitter.com/Russtopia/hopscotch)

 [HMAC]
 * HMAC-SHA256
 * HMAC-SHA512
+* WHIRLPOOL
+
+***
+**A Note on 'cryptographic agility'**
+
+It has been suggested recently to me that offering multiple cryptographic primitives is considered bad in 2021.
+
+An interesting question. See [this write-up for a discussion](https://paragonie.com/blog/2019/10/against-agility-in-cryptography-protocols).
+
+xs operates via the philosophy that **it is the server admin's prerogitive to configure local policy wrt. allowed cryptographic primitives**. The connection protocol makes no allowance for any sort of 'downgrades' or algo substitution during negotiation; there is no 'fallback' mode or two-way negotiation of what primitives to use, which would open the possibility of downgrade attacks. Unlike `ssh`, the server does not offer to clients a list of supported algorithms; the client can only offer a single configuration to the server, which it simply accepts or rejects without comment to the client.
+
+In all releases prior to v0.9.3, absent a specific whitelist of algs to allow, the server allows 'all' combinations of the above cryptographic primitives to be proposed by clients (but again, **only one** combination is proposed by the client in a single connect attempt). If the admin wishes to restrict the accepted algorithms now or at any future time, they may use the `-aK`, `-aC` and `-aH` options when launching the server to define a whitelist which excludes certain primitives.
+
+As of release v0.9.3, the default when supplying no explicit KEX, cipher or HMAC algorithms to `xsd` results in *no* algs being accepted; so the admin must decide on a specific whitelist of algorithms.
+***


 ### Conn
@ -54,8 +79,7 @@ Packets are subject to padding (random size, randomly applied as prefix or postf
 Chaffing and tunnels, if specified, are set up during initial client->server connection. Packets from the client local port(s) are sent through the main secured connection to the server's remote port(s), and vice versa, tagged with a chaff or tunnel specifier so that they can be discarded as chaff or de-multiplexed and delivered to the proper tunnel endpoints, respectively.

 ### Accounts and Passwords
-Within the xspasswd/ directory is a password-setting utility. XS uses its own password file distinct from the system /etc/passwd to authenticate clients, using standard bcrypt+salt storage. This is currently done to allow alternate login credentials via xs vs. console/ssh login, due to the experimental nature of the program. At some point in the future an option to use the system's /etc/passwd and /etc/shadow may be implemented, making the use of the auxilliary xspasswd utility optional or obsolete.
-
+Within the ```xspasswd/``` directory is a password-setting utility, ```xspasswd```, used if one wishes ```xs``` access to use separate credentials from those of the default (likely ssh) login method. In this mode, ```xsd``` uses its own password file distinct from the system /etc/passwd to authenticate clients, using standard bcrypt+salt storage. Activate this mode by invoking ```xsd``` with ```-s false```.

 HERRADURA KEX

@ -70,41 +94,40 @@ KYBER IND-CCA-2 KEM

 As of this time (Oct 2018) Kyber is one of the candidate algorithms submitted to the [NIST post-quantum cryptography project](https://csrc.nist.gov/Projects/Post-Quantum-Cryptography). The authors recommend using it in "... so-called hybrid mode in combination with established "pre-quantum" security; for example in combination with elliptic-curve Diffie-Hellman." THIS PROJECT DOES NOT DO THIS (in case you didn't notice yet, THIS PROJECT IS EXPERIMENTAL.)

-### Dependencies:

-* Recent version of go (tested, at various times, with go-1.9 to go-1.12.4)
-* [github.com/mattn/go-isatty](http://github.com/mattn/go-isatty) //terminal tty detection
-* [github.com/kr/pty](http://github.com/kr/pty) //unix pty control (server pty connections)
-* [github.com/jameskeane/bcrypt](http://github.com/jameskeane/bcrypt) //password storage/auth
-* [blitter.com/go/goutmp](https://gogs.blitter.com/RLabs/goutmp) // wtmp/lastlog C bindings for user accounting
-* [https://git.schwanenlied.me/yawning/kyber](https://git.schwanenlied.me/yawning/kyber) // golang Kyber KEM
-* [https://git.schwanenlied.me/yawning/newhope](https://git.schwanenlied.me/yawning/newhope) // golang NEWHOPE,NEWHOPE-SIMPLE KEX
-* [blitter.com/go/mtwist](https://gogs.blitter.com/RLabs/mtwist) // 64-bit Mersenne Twister PRNG
-* [blitter.com/go/cryptmt](https://gogs.blitter.com/RLabs/cryptmt) // CryptMTv1 stream cipher
+### Installing
+
+As of Go 1.8, one can directly use `go install` to get the client `xs` and server `xsd` binaries; however it is not recommended, as `xsd` requires root and for general use should be in one of the system directories, akin to other daemons. If one insists, the following will work to place them in $HOME/go/bin:
+
+```
+$ go install blitter.com/go/xs/xs@latest
+$ go install blitter.com/go/xs/xsd@latest
+```
+
+(NOTE the `-v` (version) option for binaries obtained in this manner will be blank; another reason to build them yourself locally using the steps below.)
+

 ### Get source code

 ```
-$ go get -u blitter.com/go/xs
-$ cd $GOPATH/src/blitter.com/go/xs
-$ go build ./... # install all dependent go pkgs
+$ git clone https://gogs.blitter.com/RLabs/xs
 ```


 ### To build

 ```
-$ cd $GOPATH/src/blitter.com/go/xs
-$ make clean all
+$ cd xs
+$ make clean && make
 ```

-### To install, uninstall, re-install
+### To install, uninstall, re-install (xsd server)

 ```
 $ sudo make [install | uninstall | reinstall]
 ```

-### To manage service (assuming openrc init)
+### To manage service (openrc init)

 An example init script (xsd.initrc) is provided. Consult your Linux distribution documentation for proper service/daemon installation. For openrc,

@ -113,13 +136,23 @@ $ sudo cp xsd.initrc /etc/init.d/xsd
 $ sudo rc-config add xsd default
 ```

+### To manage service (sysV init)
+
+An example init script (xsd.sysvrc) is provided. Consult your Linux distribution documentation for proper service/daemon installation. For sysV init,
+
+```
+$ sudo cp xsd.sysvrc /etc/init.d/xsd
+$ sudo sysv-rc-conf --level 2345 xsd on
+```
+
 The make system assumes installation in /usr/local/sbin (xsd, xspasswd) and /usr/local/bin (xs/xc symlink).

 ```
 $ sudo rc-config [start | restart | stop] xsd
+# .. or sudo /etc/init.d/xsd [start | restart stop]
 ```

-### To set accounts & passwords:
+### To set accounts & passwords (DEPRECATED: `-s` is now true by default)

 ```
 $ sudo touch /etc/xs.passwd
@ -154,10 +187,18 @@ or is interrupted.
 ### Setting up an 'authtoken' for scripted (password-free) logins

 Use the -g option of xs to request a token from the remote server, which will return a
-hostname:token string. Place this string into $HOME/.xs_id to allow logins without
-entering a password (obviously, $HOME/.xs_id on both server and client for the user
+hostname:token string. Place this string into $HOME/.config/xs/.xs_id to allow logins without
+entering a password (obviously, $HOME/.config/xs/.xs_id on both server and client for the user
 should *not* be world-readable.)

+```
+$ xs -g user@host.net >>~/.config/xs/.xs_id
+```
+[enter password blindly, authtoken entry will be stored in ~/.config/xs/.xs_id]
+
+NOTE you may need to remove older entries for the same host if this is not the first time you have added
+it to your .xs_id file.
+
 ### File Copying using xc

 xc is a symlink to xs, and the binary checks its own filename to determine whether
@ -183,9 +224,21 @@ xc uses a 'tarpipe' to send file data over the encrypted channel. Use the -d fla

 NOTE: Renaming while copying (eg., 'cp /foo/bar/fileA ./fileB') is NOT supported. Put another way, the destination (whether local or remote) must ALWAYS be a directory.

+If the 'pv' pipeview utility is available (http://www.ivarch.com/programs/pv.shtml) file transfer progress and bandwidth control will be available (suppress the former with the -q option, set the latter with -L &lt;bytes_per_second&gt;).
+
+Special care should be taken when doing client → server copies: since the tarpipe (should) always succeed at least sending data to the remote side, a destination with no write permission will not return a nonzero status and the client closes its end after sending all data, giving the server no opportunity to send an error code to the client.
+It is recommended to test beforehand if the server-side destination is writable (and optionally if the destination already exists, if one does not want to clobber an existing path) by:
+
+```
+$ xs -x "test -w /dest/path" me@myserver  ## If clobbering /dest/path is OK, or
+$ xs -x "test -w /dest/path -o ! -e /dest/path" me@myserver  ## To prevent clobbering
+```
+
+Perhaps in future a more complex handshake will be devised to allow the client to half-close the tarpipe, allowing the server to complete its side of the operation and send back its success or failure code, but the current connection protocol does not allow this. If this is a deal-breaking feature, please contact the maintainer.
+
 ### Tunnels

-Simple tunnels (client -> server, no reverse tunnels for now) are supported.
+Simple tunnels (client → server, no reverse tunnels for now) are supported.

 Syntax: xs -T=&lt;tunspec&gt;{,&lt;tunspec&gt;...}
 .. where &lt;tunspec&gt; is &lt;localport:remoteport&gt;
@ -196,3 +249,9 @@ Example, tunnelling ssh through xs
 * [client side, term A] ```$ xs -T=6002:7002 user@server```
 * [client side, term B] ```$ ssh user@localhost -p 6002```

+
+### Building for FreeBSD
+
+The Makefile(s) to build require GNU make (gmake).
+Please install and invoke build via:
+```$ gmake clean all```
--- a/TODO.txt
+++ b/TODO.txt
@ -18,6 +18,7 @@ Architecture
  (parts split out into hkexnet/*, hkexsession.go)
 (DONE) - Make KEx fully-pluggable: isolate all code to do with Herradura into a
  KEx-neutral pkg so it can be swapped out for other methods (eg., DH etc.)
+(DONE - test branch) - Use system password db (/etc/{passwd,shadow})

 Features
 (DONE) - Support for hkcp (hkex-cp) - secure file copy protocol
--- a/auth.go
+++ b/auth.go
@ -2,7 +2,7 @@ package xs

 // Package xs - a secure terminal client/server written from scratch in Go
 //
-// Copyright (c) 2017-2019 Russell Magee
+// Copyright (c) 2017-2020 Russell Magee
 // Licensed under the terms of the MIT license (see LICENSE.mit in this
 // distribution)
 //
@ -13,28 +13,95 @@ package xs
 import (
 	"bytes"
 	"encoding/csv"
+	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
 	"log"
+	"os"
 	"os/user"
 	"runtime"
 	"strings"

+	"blitter.com/go/xs/xsnet"
 	"github.com/jameskeane/bcrypt"
+	passlib "gopkg.in/hlandau/passlib.v1"
 )

-func userExistsOnSystem(who string) bool {
-	_, userErr := user.Lookup(who)
-	return userErr == nil
+type AuthCtx struct {
+	reader     func(string) ([]byte, error)     // eg. ioutil.ReadFile()
+	userlookup func(string) (*user.User, error) // eg. os/user.Lookup()
 }

+func NewAuthCtx( /*reader func(string) ([]byte, error), userlookup func(string) (*user.User, error)*/ ) (ret *AuthCtx) {
+	ret = &AuthCtx{ioutil.ReadFile, user.Lookup}
+	return
+}
+
+// --------- System passwd/shadow auth routine(s) --------------
+
+// VerifyPass verifies a password against system standard shadow file
+// Note auxilliary fields for expiry policy are *not* inspected.
+func VerifyPass(ctx *AuthCtx, user, password string) (bool, error) {
+	if ctx.reader == nil {
+		ctx.reader = ioutil.ReadFile // dependency injection hides that this is required
+	}
+	passlib.UseDefaults(passlib.Defaults20180601)
+	var pwFileName string
+	if runtime.GOOS == "linux" {
+		pwFileName = "/etc/shadow"
+	} else if runtime.GOOS == "freebsd" {
+		pwFileName = "/etc/master.passwd"
+	} else {
+		return false, errors.New("Unsupported platform")
+	}
+	pwFileData, e := ctx.reader(pwFileName)
+	if e != nil {
+		return false, e
+	}
+	pwLines := strings.Split(string(pwFileData), "\n")
+	if len(pwLines) < 1 {
+		return false, errors.New("Empty shadow file!")
+	} else {
+		var line string
+		var hash string
+		var idx int
+		for idx = range pwLines {
+			line = pwLines[idx]
+			lFields := strings.Split(line, ":")
+			if lFields[0] == user {
+				hash = lFields[1]
+				break
+			}
+		}
+		if len(hash) == 0 {
+			return false, errors.New("nil hash!")
+		} else {
+			pe := passlib.VerifyNoUpgrade(password, hash)
+			if pe != nil {
+				return false, pe
+			}
+		}
+	}
+	return true, nil
+}
+
+// --------- End System passwd/shadow auth routine(s) ----------
+
+// ------------- xs-local passwd auth routine(s) ---------------
+
 // AuthUserByPasswd checks user login information using a password.
 // This checks /etc/xs.passwd for auth info, and system /etc/passwd
 // to cross-check the user actually exists.
 // nolint: gocyclo
-func AuthUserByPasswd(username string, auth string, fname string) (valid bool, allowedCmds string) {
-	b, e := ioutil.ReadFile(fname) // nolint: gosec
+func AuthUserByPasswd(ctx *AuthCtx, username string, auth string, fname string) (valid bool, allowedCmds string) {
+	if ctx.reader == nil {
+		ctx.reader = ioutil.ReadFile // dependency injection hides that this is required
+	}
+	if ctx.userlookup == nil {
+		ctx.userlookup = user.Lookup // again for dependency injection as dep is now hidden
+	}
+	b, e := ctx.reader(fname) // nolint: gosec
 	if e != nil {
 		valid = false
 		log.Printf("ERROR: Cannot read %s!\n", fname)
@ -78,27 +145,37 @@ func AuthUserByPasswd(username string, auth string, fname string) (valid bool, a
 	r = nil
 	runtime.GC()

-	if !userExistsOnSystem(username) {
+	_, userErr := ctx.userlookup(username)
+	if userErr != nil {
 		valid = false
 	}
 	return
 }

+// ------------- End xs-local passwd auth routine(s) -----------
+
 // AuthUserByToken checks user login information against an auth token.
-// Auth tokens are stored in each user's $HOME/.xs_id and are requested
+// Auth tokens are stored in each user's $HOME/.config/xs/.xs_id and are requested
 // via the -g option.
 // The function also check system /etc/passwd to cross-check the user
 // actually exists.
-func AuthUserByToken(username string, connhostname string, auth string) (valid bool) {
+func AuthUserByToken(ctx *AuthCtx, username string, connhostname string, auth string) (valid bool) {
+	if ctx.reader == nil {
+		ctx.reader = ioutil.ReadFile // dependency injection hides that this is required
+	}
+	if ctx.userlookup == nil {
+		ctx.userlookup = user.Lookup // again for dependency injection as dep is now hidden
+	}
+
 	auth = strings.TrimSpace(auth)
-	u, ue := user.Lookup(username)
+	u, ue := ctx.userlookup(username)
 	if ue != nil {
 		return false
 	}

-	b, e := ioutil.ReadFile(fmt.Sprintf("%s/.xs_id", u.HomeDir))
+	b, e := ctx.reader(fmt.Sprintf("%s/%s", u.HomeDir, xsnet.XS_ID_AUTHTOKFILE))
 	if e != nil {
-		log.Printf("INFO: Cannot read %s/.xs_id\n", u.HomeDir)
+		log.Printf("INFO: Cannot read %s/%s\n", u.HomeDir, xsnet.XS_ID_AUTHTOKFILE)
 		return false
 	}

@ -106,25 +183,53 @@ func AuthUserByToken(username string, connhostname string, auth string) (valid b

 	r.Comma = ':'
 	r.Comment = '#'
-	r.FieldsPerRecord = 2 // connhost:authtoken
+	r.FieldsPerRecord = 3 // connhost:username:authtoken
 	for {
 		record, err := r.Read()
 		if err == io.EOF {
 			return false
 		}
+		if len(record) < 3 ||
+			len(record[0]) < 1 ||
+			len(record[1]) < 1 ||
+			len(record[2]) < 1 {
+			return false
+		}
 		record[0] = strings.TrimSpace(record[0])
 		record[1] = strings.TrimSpace(record[1])
+		record[2] = strings.TrimSpace(record[2])
 		//fmt.Println("auth:", auth, "record:",
-		//	strings.Join([]string{record[0], record[1]}, ":"))
+		//	strings.Join([]string{record[0], record[1], record[2]}, ":"))

 		if (connhostname == record[0]) &&
-			(auth == strings.Join([]string{record[0], record[1]}, ":")) {
+			username == record[1] &&
+			(auth == strings.Join([]string{record[0], record[1], record[2]}, ":")) {
 			valid = true
 			break
 		}
 	}
-	if !userExistsOnSystem(username) {
+	_, userErr := ctx.userlookup(username)
+	if userErr != nil {
 		valid = false
 	}
 	return
 }
+
+func GetTool(tool string) (ret string) {
+	ret = "/bin/" + tool
+	_, err := os.Stat(ret)
+	if err == nil {
+		return ret
+	}
+	ret = "/usr/bin/" + tool
+	_, err = os.Stat(ret)
+	if err == nil {
+		return ret
+	}
+	ret = "/usr/local/bin/" + tool
+	_, err = os.Stat(ret)
+	if err == nil {
+		return ret
+	}
+	return ""
+}
--- a/auth_test.go
+++ b/auth_test.go
@ -0,0 +1,212 @@
+package xs
+
+import (
+	"errors"
+	"fmt"
+	"os/user"
+	"strings"
+	"testing"
+)
+
+type userVerifs struct {
+	user   string
+	passwd string
+	good   bool
+}
+
+var (
+	dummyShadowA = `johndoe:$6$EeQlTtn/KXdSh6CW$UHbFuEw3UA0Jg9/GoPHxgWk6Ws31x3IjqsP22a9pVMOte0yQwX1.K34oI4FACu8GRg9DArJ5RyWUE9m98qwzZ1:18310:0:99999:7:::
+joebloggs:$6$F.0IXOrb0w0VJHG1$3O4PYyng7F3hlh42mbroEdQZvslybY5etPPiLMQJ1xosjABY.Q4xqAfyIfe03Du61ZjGQIt3nL0j12P9k1fsK/:18310:0:99999:7:::
+disableduser:!:18310::::::`
+
+	dummyAuthTokenFile = "hostA:johndoe:abcdefg\nhostB:imposter:wxyz\n"
+
+	dummyXsPasswdFile = `#username:salt:authCookie
+bobdobbs:$2a$12$9vqGkFqikspe/2dTARqu1O:$2a$12$9vqGkFqikspe/2dTARqu1OuDKCQ/RYWsnaFjmi.HtmECRkxcZ.kBK
+notbob:$2a$12$cZpiYaq5U998cOkXzRKdyu:$2a$12$cZpiYaq5U998cOkXzRKdyuJ2FoEQyVLa3QkYdPQk74VXMoAzhvuP6
+`
+
+	testGoodUsers = []userVerifs{
+		{"johndoe", "testpass", true},
+		{"joebloggs", "testpass2", true},
+		{"johndoe", "badpass", false},
+	}
+
+	testXsPasswdUsers = []userVerifs{
+		{"bobdobbs", "praisebob", true},
+		{"notbob", "imposter", false},
+	}
+
+	userlookup_arg_u string
+	readfile_arg_f   string
+)
+
+func newMockAuthCtx(reader func(string) ([]byte, error), userlookup func(string) (*user.User, error)) (ret *AuthCtx) {
+	ret = &AuthCtx{reader, userlookup}
+	return
+}
+
+func _mock_user_Lookup(username string) (*user.User, error) {
+	username = userlookup_arg_u
+	if username == "baduser" {
+		return &user.User{}, errors.New("bad user")
+	}
+	urec := &user.User{Uid: "1000", Gid: "1000", Username: username, Name: "Full Name", HomeDir: "/home/user"}
+	fmt.Printf("  [mock user rec:%v]\n", urec)
+	return urec, nil
+}
+
+func _mock_ioutil_ReadFile(f string) ([]byte, error) {
+	f = readfile_arg_f
+	if f == "/etc/shadow" {
+		fmt.Println("  [mocking ReadFile(\"/etc/shadow\")]")
+		return []byte(dummyShadowA), nil
+	}
+	if f == "/etc/xs.passwd" {
+		fmt.Println("  [mocking ReadFile(\"/etc/xs.passwd\")]")
+		return []byte(dummyXsPasswdFile), nil
+	}
+	if strings.Contains(f, "/.xs_id") {
+		fmt.Println("  [mocking ReadFile(\".xs_id\")]")
+		return []byte(dummyAuthTokenFile), nil
+	}
+	return []byte{}, errors.New("no readfile_arg_f supplied")
+}
+
+func _mock_ioutil_ReadFileEmpty(f string) ([]byte, error) {
+	return []byte{}, nil
+}
+
+func _mock_ioutil_ReadFileHasError(f string) ([]byte, error) {
+	return []byte{}, errors.New("IO Error")
+}
+
+func TestVerifyPass(t *testing.T) {
+	readfile_arg_f = "/etc/shadow"
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFile, nil)
+	for idx, rec := range testGoodUsers {
+		stat, e := VerifyPass(ctx, rec.user, rec.passwd)
+		if rec.good && (!stat || e != nil) {
+			t.Fatalf("failed %d\n", idx)
+		}
+	}
+}
+
+func TestVerifyPassFailsOnEmptyFile(t *testing.T) {
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFileEmpty, nil)
+	stat, e := VerifyPass(ctx, "johndoe", "somepass")
+	if stat || (e == nil) {
+		t.Fatal("failed to fail w/empty file")
+	}
+}
+
+func TestVerifyPassFailsOnFileError(t *testing.T) {
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFileEmpty, nil)
+	stat, e := VerifyPass(ctx, "johndoe", "somepass")
+	if stat || (e == nil) {
+		t.Fatal("failed to fail on ioutil.ReadFile error")
+	}
+}
+
+func TestVerifyPassFailsOnDisabledEntry(t *testing.T) {
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFileEmpty, nil)
+	stat, e := VerifyPass(ctx, "disableduser", "!")
+	if stat || (e == nil) {
+		t.Fatal("failed to fail on disabled user entry")
+	}
+}
+
+////
+
+func TestAuthUserByTokenFailsOnMissingEntryForHost(t *testing.T) {
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFile, _mock_user_Lookup)
+	stat := AuthUserByToken(ctx, "johndoe", "hostZ", "abcdefg")
+	if stat {
+		t.Fatal("failed to fail on missing/mismatched host entry")
+	}
+}
+
+func TestAuthUserByTokenFailsOnMissingEntryForUser(t *testing.T) {
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFile, _mock_user_Lookup)
+	stat := AuthUserByToken(ctx, "unkuser", "hostA", "abcdefg")
+	if stat {
+		t.Fatal("failed to fail on wrong user")
+	}
+}
+
+func TestAuthUserByTokenFailsOnUserLookupFailure(t *testing.T) {
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFile, _mock_user_Lookup)
+	userlookup_arg_u = "baduser"
+	stat := AuthUserByToken(ctx, "johndoe", "hostA", "abcdefg")
+	if stat {
+		t.Fatal("failed to fail with bad return from user.Lookup()")
+	}
+}
+
+func TestAuthUserByTokenFailsOnMismatchedTokenForUser(t *testing.T) {
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFile, _mock_user_Lookup)
+	stat := AuthUserByToken(ctx, "johndoe", "hostA", "badtoken")
+	if stat {
+		t.Fatal("failed to fail with valid user, bad token")
+	}
+}
+
+func TestAuthUserByTokenSucceedsWithMatchedUserAndToken(t *testing.T) {
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFile, _mock_user_Lookup)
+	userlookup_arg_u = "johndoe"
+	readfile_arg_f = "/.xs_id"
+	stat := AuthUserByToken(ctx, userlookup_arg_u, "hostA", "hostA:johndoe:abcdefg")
+	if !stat {
+		t.Fatal("failed with valid user and token")
+	}
+}
+
+func TestAuthUserByPasswdFailsOnEmptyFile(t *testing.T) {
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFileEmpty, _mock_user_Lookup)
+	userlookup_arg_u = "bobdobbs"
+	readfile_arg_f = "/etc/xs.passwd"
+	stat, _ := AuthUserByPasswd(ctx, userlookup_arg_u, "praisebob", readfile_arg_f)
+	if stat {
+		t.Fatal("failed to fail with missing xs.passwd file")
+	}
+}
+
+func TestAuthUserByPasswdFailsOnBadAuth(t *testing.T) {
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFile, _mock_user_Lookup)
+	userlookup_arg_u = "bobdobbs"
+	readfile_arg_f = "/etc/xs.passwd"
+	stat, _ := AuthUserByPasswd(ctx, userlookup_arg_u, "wrongpass", readfile_arg_f)
+	if stat {
+		t.Fatal("failed to fail with valid user, incorrect passwd in xs.passwd file")
+	}
+}
+
+func TestAuthUserByPasswdFailsOnBadUser(t *testing.T) {
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFile, _mock_user_Lookup)
+	userlookup_arg_u = "bobdobbs"
+	readfile_arg_f = "/etc/xs.passwd"
+	stat, _ := AuthUserByPasswd(ctx, userlookup_arg_u, "theotherbob", readfile_arg_f)
+	if stat {
+		t.Fatal("failed to fail on invalid user vs. xs.passwd file")
+	}
+}
+
+func TestAuthUserByPasswdPassesOnGoodAuth(t *testing.T) {
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFile, _mock_user_Lookup)
+	userlookup_arg_u = "bobdobbs"
+	readfile_arg_f = "/etc/xs.passwd"
+	stat, _ := AuthUserByPasswd(ctx, userlookup_arg_u, "praisebob", readfile_arg_f)
+	if !stat {
+		t.Fatal("failed on valid user w/correct passwd in xs.passwd file")
+	}
+}
+
+func TestAuthUserByPasswdPassesOnOtherGoodAuth(t *testing.T) {
+	ctx := newMockAuthCtx(_mock_ioutil_ReadFile, _mock_user_Lookup)
+	userlookup_arg_u = "notbob"
+	readfile_arg_f = "/etc/xs.passwd"
+	stat, _ := AuthUserByPasswd(ctx, userlookup_arg_u, "imposter", readfile_arg_f)
+	if !stat {
+		t.Fatal("failed on valid user 2nd entry w/correct passwd in xs.passwd file")
+	}
+}
--- a/bacillus/ci_pushbuild.sh
+++ b/bacillus/ci_pushbuild.sh
@ -0,0 +1,114 @@
+#!/bin/bash
+#
+## bacillus (https://gogs.blitter.com/Russtopia/bacillus) build/test CI script
+
+export GOPATH="${HOME}/go"
+export PATH=/usr/local/bin:/usr/bin:/usr/lib/ccache/bin:/bin:$GOPATH/bin
+unset GO111MODULE
+#export GOPROXY="direct"
+#!# GOCACHE will be phased out in v1.12. [github.com/golang/go/issues/26809]
+#!export GOCACHE="${HOME}/.cache/go-build"
+
+echo "workdir: ${BACILLUS_WORKDIR}"
+mkdir -p "${BACILLUS_ARTFDIR}"
+
+echo "---"
+go env
+echo "---"
+echo "passed env:"
+env
+echo "---"
+
+cd ${REPO}
+branch=$(git for-each-ref --sort=-committerdate --format='%(refname)' | head -n 1)
+echo "Building most recent push on branch $branch"
+git checkout "$branch"
+ls
+
+go mod init
+go mod tidy
+
+############
+stage "Build"
+############
+echo "Invoking 'make clean' ..."
+make clean
+echo "Invoking 'make all' ..."
+make all
+
+############
+stage "Lint"
+############
+make lint
+
+############
+stage "UnitTests"
+############
+go test -v .
+
+############
+stage "Test(Authtoken)"
+############
+if [ -f ~/.config/xs/.xs_id ]; then
+  echo "Clearing test user $USER .xs_id file ..."
+  mv ~/.config/xs/.xs_id ~/.config/xs/.xs_id.bak
+fi
+echo "Setting dummy authtoken in .xs_id ..."
+echo "localhost:${USER}:asdfasdfasdf" >~/.config/xs/.xs_id
+echo "Performing remote command on @localhost via authtoken login ..."
+tokentest=$(timeout 10 xs -x "echo -n FOO" @localhost)
+if [ "${tokentest}" != "FOO" ]; then
+  echo "AUTHTOKEN LOGIN FAILED"
+  exit 1
+else
+  echo "client cmd performed OK."
+  unset tokentest
+fi
+
+############
+stage "Test(xc S->C)"
+############
+echo "Testing secure copy from server -> client ..."
+./xc_testfiles.sh
+
+tmpdir=$$
+mkdir -p /tmp/$tmpdir
+cd /tmp/$tmpdir
+xc @localhost:${BACILLUS_WORKDIR}/build/xs/cptest .
+echo -n "Integrity check on copied files (sha1sum) ..."
+sha1sum $(find cptest -type f | sort) >sc.sha1sum
+diff sc.sha1sum ${BACILLUS_WORKDIR}/build/xs/cptest.sha1sum
+stat=$?
+cd -
+
+rm -rf /tmp/$tmpdir
+if [ $stat -eq "0" ]; then
+  echo "OK."
+else
+  echo "FAILED!"
+  exit $stat
+fi
+
+############
+stage "Test(xc C->S)"
+############
+echo "TODO ..."
+
+if [ -f ~/.config/xs/.xs_id.bak ]; then
+  echo "Restoring test user $USER .xs_id file ..."
+  mv ~/.config/xs/.xs_id.bak ~/.config/xs/.xs_id
+fi
+
+############
+stage "Artifacts"
+############
+echo -n "Creating tarfile ..."
+tar -cz --exclude=.git --exclude=cptest -f ${BACILLUS_ARTFDIR}/xs.tgz .
+
+############
+stage "Cleanup"
+############
+rm -rf cptest
+
+echo
+echo "--Done--"
--- a/consts.go
+++ b/consts.go
@ -1,6 +1,6 @@
 // Package xs - a secure terminal client/server written from scratch in Go
 //
-// Copyright (c) 2017-2019 Russell Magee
+// Copyright (c) 2017-2020 Russell Magee
 // Licensed under the terms of the MIT license (see LICENSE.mit in this
 // distribution)
 //
--- a/cptest.sha1sum
+++ b/cptest.sha1sum
@ -1,6 +1,6 @@
-306637b5c621892078ebadd9454a78820a000598  cptest/file16KB
-1a118dfff291352eb4aec02c34f4f957669460fc  cptest/file1KB
-f474d5da45890b7cb5b0ae84c8ade5abcb3b4474  cptest/file32KB
-03939175ceac92b9c6464d037a0243e22563c423  cptest/file6B
-da67c7698b25d94c0cc20284ba9d4008cdee201b  cptest/subdir/file32MB
-9da9888265371375b48c224b94a0b3132b7ddc41  cptest/subdir/file64MB
+6010a446cdcf8c1203c2d08998cc69a8c88f77d5  cptest/file16KB
+f086ea96f3718efd78e6791178f967585acb3701  cptest/file1KB
+6061e16c3d3840712d0b8e5268c49b5c2f8137ac  cptest/file32KB
+490af32035bbe737480f06439a02d91a171ac407  cptest/file6B
+e4a8a4ad9678b7265a28c5f0cb5b078e1049ea23  cptest/subdir/file32MB
+82b50550c7d0e0d6ac18d9d0796b6814c3e038bf  cptest/subdir/file64MB
--- a/go.mod
+++ b/go.mod
@ -1,27 +0,0 @@
-module blitter.com/go/xs
-
-go 1.12
-
-require (
-	blitter.com/go/cryptmt v1.0.0
-	blitter.com/go/goutmp v1.0.1
-	blitter.com/go/herradurakex v1.0.0
-	blitter.com/go/mtwist v1.0.1 // indirect
-	blitter.com/go/wanderer v0.8.0
-	git.schwanenlied.me/yawning/chacha20.git v0.0.0-20170904085104-e3b1f968fc63 // indirect
-	git.schwanenlied.me/yawning/kyber.git v0.0.0-20180530164001-a270899bd22c
-	git.schwanenlied.me/yawning/newhope.git v0.0.0-20170622154529-9598792ba8f2
-	github.com/jameskeane/bcrypt v0.0.0-20120420032655-c3cd44c1e20f
-	github.com/klauspost/cpuid v1.2.2 // indirect
-	github.com/klauspost/reedsolomon v1.9.3 // indirect
-	github.com/kr/pty v1.1.4
-	github.com/mattn/go-isatty v0.0.7
-	github.com/pkg/errors v0.8.1 // indirect
-	github.com/templexxx/cpufeat v0.0.0-20180724012125-cef66df7f161 // indirect
-	github.com/templexxx/xor v0.0.0-20181023030647-4e92f724b73b // indirect
-	github.com/tjfoc/gmsm v1.0.1 // indirect
-	github.com/xtaci/kcp-go v5.4.19+incompatible
-	golang.org/x/crypto v0.0.0-20190417174047-f416ebab96af
-	golang.org/x/net v0.0.0-20191209160850-c0dbc17a3553 // indirect
-	golang.org/x/sys v0.0.0-20190416152802-12500544f89f
-)
--- a/go.sum
+++ b/go.sum
@ -1,47 +0,0 @@
-blitter.com/go/cryptmt v1.0.0 h1:n+cNP/ReZrNe/w5FbD8DSfv0Wpj48nxhmMoLEk4hPXs=
-blitter.com/go/cryptmt v1.0.0/go.mod h1:tdME2J3O4agaDAYIYNQzzuB28yVGnPSMmV3a/ucSU84=
-blitter.com/go/goutmp v1.0.1 h1:jBqtp6pDwSbF4QEC3DjNfyaS8Nv5dFCOyaTfSbbb7TU=
-blitter.com/go/goutmp v1.0.1/go.mod h1:gtlbjC8xGzMk/Cf0BpnVltSa3awOqJ+B5WAxVptTMxk=
-blitter.com/go/herradurakex v1.0.0 h1:6XaxY+JLT1HUWPF0gYJnjX3pVjrw4YhYZEzZ1U0wkyc=
-blitter.com/go/herradurakex v1.0.0/go.mod h1:m3+vYZX+2dDjdo+n/HDnXEYJX9pwmNeQLgAfJM8mtxw=
-blitter.com/go/mtwist v1.0.0 h1:/Vg6k12+DC+fokeRrLApL22hZS/EqEazJTo/FDdbDog=
-blitter.com/go/mtwist v1.0.0/go.mod h1:aU82Nx8+b1v8oZRNqImfEDzDTPim81rY0ACKAIclV18=
-blitter.com/go/mtwist v1.0.1 h1:PxmoWexfMpLmc8neHP/PcRc3s17ct7iz4d5W/qJVt04=
-blitter.com/go/mtwist v1.0.1/go.mod h1:aU82Nx8+b1v8oZRNqImfEDzDTPim81rY0ACKAIclV18=
-blitter.com/go/wanderer v0.8.0 h1:xT7lKdKLSyonVf0vZW6R46E3gz3B5pJ1VDBlsa4ULDI=
-blitter.com/go/wanderer v0.8.0/go.mod h1:FX1pAnZ5woEavy5CUIZco0/Gc2Msb3U0zsmi+6Hs4Rw=
-git.schwanenlied.me/yawning/chacha20.git v0.0.0-20170904085104-e3b1f968fc63 h1:bwZNsbw3qFbg6ox55HrA37nPmh+/wtJxZ7uWeiAdUUc=
-git.schwanenlied.me/yawning/chacha20.git v0.0.0-20170904085104-e3b1f968fc63/go.mod h1:NYi4Ifd1g/YbhIDgDfw6t7QdsW4tofQWMX/+FiDtJWs=
-git.schwanenlied.me/yawning/kyber.git v0.0.0-20180530164001-a270899bd22c/go.mod h1:QrbgzU5EL/1jaMD5pD4Tiikj3R5elPMa+RMwFUTGwQU=
-git.schwanenlied.me/yawning/newhope.git v0.0.0-20170622154529-9598792ba8f2 h1:89TYv/+wotJ+QWrH5B/yN0pEQutr2V/5za0VoYiVGCM=
-git.schwanenlied.me/yawning/newhope.git v0.0.0-20170622154529-9598792ba8f2/go.mod h1:weMqACFGzJs4Ni+K9shsRd02N4LkDrtGlkRxISK+II0=
-github.com/jameskeane/bcrypt v0.0.0-20120420032655-c3cd44c1e20f/go.mod h1:u+9Snq0w+ZdYKi8BBoaxnEwWu0fY4Kvu9ByFpM51t1s=
-github.com/klauspost/cpuid v1.2.2 h1:1xAgYebNnsb9LKCdLOvFWtAxGU/33mjJtyOVbmUa0Us=
-github.com/klauspost/cpuid v1.2.2/go.mod h1:Pj4uuM528wm8OyEC2QMXAi2YiTZ96dNQPGgoMS4s3ek=
-github.com/klauspost/reedsolomon v1.9.3 h1:N/VzgeMfHmLc+KHMD1UL/tNkfXAt8FnUqlgXGIduwAY=
-github.com/klauspost/reedsolomon v1.9.3/go.mod h1:CwCi+NUr9pqSVktrkN+Ondf06rkhYZ/pcNv7fu+8Un4=
-github.com/kr/pty v1.1.4 h1:5Myjjh3JY/NaAi4IsUbHADytDyl1VE1Y9PXDlL+P/VQ=
-github.com/kr/pty v1.1.4/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
-github.com/mattn/go-isatty v0.0.7 h1:UvyT9uN+3r7yLEYSlJsbQGdsaB/a0DlgWP3pql6iwOc=
-github.com/mattn/go-isatty v0.0.7/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
-github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
-github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
-github.com/templexxx/cpufeat v0.0.0-20180724012125-cef66df7f161 h1:89CEmDvlq/F7SJEOqkIdNDGJXrQIhuIx9D2DBXjavSU=
-github.com/templexxx/cpufeat v0.0.0-20180724012125-cef66df7f161/go.mod h1:wM7WEvslTq+iOEAMDLSzhVuOt5BRZ05WirO+b09GHQU=
-github.com/templexxx/xor v0.0.0-20181023030647-4e92f724b73b h1:mnG1fcsIB1d/3vbkBak2MM0u+vhGhlQwpeimUi7QncM=
-github.com/templexxx/xor v0.0.0-20181023030647-4e92f724b73b/go.mod h1:5XA7W9S6mni3h5uvOC75dA3m9CCCaS83lltmc0ukdi4=
-github.com/tjfoc/gmsm v1.0.1 h1:R11HlqhXkDospckjZEihx9SW/2VW0RgdwrykyWMFOQU=
-github.com/tjfoc/gmsm v1.0.1/go.mod h1:XxO4hdhhrzAd+G4CjDqaOkd0hUzmtPR/d3EiBBMn/wc=
-github.com/xtaci/kcp-go v5.4.19+incompatible h1:vv7Ar1D9WZGiv6deIOluxrC26Oin/2jFtx8sFU5tlvw=
-github.com/xtaci/kcp-go v5.4.19+incompatible/go.mod h1:bN6vIwHQbfHaHtFpEssmWsN45a+AZwO7eyRCmEIbtvE=
-golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/crypto v0.0.0-20190417174047-f416ebab96af h1:6qGQw30u837TXZbCmLFR9AVA+RjJU1LIbvk0oIkDZGY=
-golang.org/x/crypto v0.0.0-20190417174047-f416ebab96af/go.mod h1:WFFai1msRO1wXaEeE5yQxYXgSfI8pQAWXbQop6sCtWE=
-golang.org/x/net v0.0.0-20191209160850-c0dbc17a3553 h1:efeOvDhwQ29Dj3SdAV/MJf8oukgn+8D8WgaCaRMchF8=
-golang.org/x/net v0.0.0-20191209160850-c0dbc17a3553/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
-golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20190222072716-a9d3bda3a223/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20190403152447-81d4e9dc473e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20190416152802-12500544f89f h1:1ZH9RnjNgLzh6YrsRp/c6ddZ8Lq0fq9xztNOoWJ2sz4=
-golang.org/x/sys v0.0.0-20190416152802-12500544f89f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
--- a/logger/Makefile
+++ b/logger/Makefile
@ -2,8 +2,14 @@

 EXE = $(notdir $(shell pwd))

+ifeq ($(GARBLE),y)
+GO=garble -literals -tiny -debugdir=garbled
+else
+GO = go
+endif
+
 all:
-	go build .
+	$(GO) build .

 clean:
 	$(RM) $(EXE) $(EXE).exe
--- a/logger/logger_bsd.go
+++ b/logger/logger_bsd.go
@ -0,0 +1,156 @@
+// +build freebsd
+
+// Package logger is a wrapper around UNIX syslog, so that it also may
+// be wrapped with something else for Windows (Sadly, the stdlib log/syslog
+// is frozen, and there is no Windows implementation.)
+package logger
+
+import (
+	sl "log/syslog"
+)
+
+// Priority is the logger priority
+type Priority = sl.Priority
+
+// Writer is a syslog Writer
+type Writer = sl.Writer
+
+// nolint: golint
+const (
+	// Severity.
+
+	// From /usr/include/sys/syslog.h.
+	// These are the same on Linux, BSD, and OS X.
+	LOG_EMERG Priority = iota
+	LOG_ALERT
+	LOG_CRIT
+	LOG_ERR
+	LOG_WARNING
+	LOG_NOTICE
+	LOG_INFO
+	LOG_DEBUG
+)
+
+// nolint: golint
+const (
+	// Facility.
+
+	// From /usr/include/sys/syslog.h.
+	// These are the same up to LOG_FTP on Linux, BSD, and OS X.
+	LOG_KERN Priority = iota << 3
+	LOG_USER
+	LOG_MAIL
+	LOG_DAEMON
+	LOG_AUTH
+	LOG_SYSLOG
+	LOG_LPR
+	LOG_NEWS
+	LOG_UUCP
+	LOG_CRON
+	LOG_AUTHPRIV
+	LOG_FTP
+	_ // unused
+	_ // unused
+	_ // unused
+	_ // unused
+	LOG_LOCAL0
+	LOG_LOCAL1
+	LOG_LOCAL2
+	LOG_LOCAL3
+	LOG_LOCAL4
+	LOG_LOCAL5
+	LOG_LOCAL6
+	LOG_LOCAL7
+)
+
+var (
+	l *sl.Writer
+)
+
+// New returns a new log Writer.
+func New(flags Priority, tag string) (w *Writer, e error) {
+	w, e = sl.New(flags, tag)
+	l = w
+	return w, e
+}
+
+// Alert returns a log Alert error
+func Alert(s string) error {
+	if l != nil {
+		return l.Alert(s)
+	}
+	return nil
+
+}
+
+// LogClose closes the log Writer.
+func LogClose() error {
+	if l != nil {
+		return l.Close()
+	}
+	return nil
+}
+
+// LogCrit returns a log Alert error
+func LogCrit(s string) error {
+	if l != nil {
+		return l.Crit(s)
+	}
+	return nil
+}
+
+// LogDebug returns a log Debug error
+func LogDebug(s string) error {
+	if l != nil {
+		return l.Debug(s)
+	}
+	return nil
+}
+
+// LogEmerg returns a log Emerg error
+func LogEmerg(s string) error {
+	if l != nil {
+		return l.Emerg(s)
+	}
+	return nil
+}
+
+// LogErr returns a log Err error
+func LogErr(s string) error {
+	if l != nil {
+		return l.Err(s)
+	}
+	return nil
+}
+
+// LogInfo returns a log Info error
+func LogInfo(s string) error {
+	if l != nil {
+		return l.Info(s)
+	}
+	return nil
+}
+
+// LogNotice returns a log Notice error
+func LogNotice(s string) error {
+	if l != nil {
+		return l.Notice(s)
+	}
+	return nil
+}
+
+// LogWarning returns a log Warning error
+func LogWarning(s string) error {
+	if l != nil {
+		return l.Warning(s)
+	}
+	return nil
+}
+
+// LogWrite writes to the logger at default level
+func LogWrite(b []byte) (int, error) {
+	if l != nil {
+		return l.Write(b)
+	}
+	return len(b),nil
+}
--- a/logger/logger_linux.go
+++ b/logger/logger_linux.go
@ -11,6 +11,7 @@ import (

 // Priority is the logger priority
 type Priority = sl.Priority
+
 // Writer is a syslog Writer
 type Writer = sl.Writer

@ -75,50 +76,81 @@ func New(flags Priority, tag string) (w *Writer, e error) {

 // Alert returns a log Alert error
 func Alert(s string) error {
+	if l != nil {
 		return l.Alert(s)
+	}
+	return nil
+
 }

 // LogClose closes the log Writer.
 func LogClose() error {
+	if l != nil {
 		return l.Close()
+	}
+	return nil
 }

 // LogCrit returns a log Alert error
 func LogCrit(s string) error {
+	if l != nil {
 		return l.Crit(s)
+	}
+	return nil
 }

 // LogDebug returns a log Debug error
 func LogDebug(s string) error {
+	if l != nil {
 		return l.Debug(s)
+	}
+	return nil
 }

 // LogEmerg returns a log Emerg error
 func LogEmerg(s string) error {
+	if l != nil {
 		return l.Emerg(s)
+	}
+	return nil
 }

 // LogErr returns a log Err error
 func LogErr(s string) error {
+	if l != nil {
 		return l.Err(s)
+	}
+	return nil
 }

 // LogInfo returns a log Info error
 func LogInfo(s string) error {
+	if l != nil {
 		return l.Info(s)
+	}
+	return nil
 }

 // LogNotice returns a log Notice error
 func LogNotice(s string) error {
+	if l != nil {
 		return l.Notice(s)
+	}
+	return nil
 }

 // LogWarning returns a log Warning error
 func LogWarning(s string) error {
+	if l != nil {
 		return l.Warning(s)
+	}
+	return nil
 }

 // LogWrite writes to the logger at default level
 func LogWrite(b []byte) (int, error) {
+	if l != nil {
 		return l.Write(b)
+	}
+	return len(b),nil
 }
--- a/logger/logger_windows.go
+++ b/logger/logger_windows.go
@ -1,5 +1,5 @@
 // +build windows
-//
+
 // Wrapper around UNIX syslog, so that it also may be wrapped
 // with something else for Windows.
 package logger
--- a/session.go
+++ b/session.go
@ -2,7 +2,7 @@ package xs

 // Package xs - a secure terminal client/server written from scratch in Go
 //
-// Copyright (c) 2017-2019 Russell Magee
+// Copyright (c) 2017-2020 Russell Magee
 // Licensed under the terms of the MIT license (see LICENSE.mit in this
 // distribution)
 //
@ -96,7 +96,7 @@ func (h Session) AuthCookie(reallyShow bool) []byte {
 	return []byte("**REDACTED**")
 }

-// SetAuthCookie stores the authcookie (essential the password) used to
+// SetAuthCookie stores the authcookie (essentially the password) used to
 // authenticate the Session.
 func (h *Session) SetAuthCookie(a []byte) {
 	h.authCookie = a
--- a/session_test.go
+++ b/session_test.go
@ -0,0 +1,30 @@
+package xs
+
+import (
+	"testing"
+)
+
+func _newMockSession() (s *Session) {
+	s = &Session{op: []byte("A"),
+		who:        []byte("johndoe"),
+		connhost:   []byte("host"),
+		termtype:   []byte("vt100"),
+		cmd:        []byte("/bin/false"),
+		authCookie: []byte("authcookie"),
+		status:     0}
+	return s
+}
+
+func TestSessionAuthCookieShowTrue(t *testing.T) {
+	sess := _newMockSession()
+	if string(sess.AuthCookie(true)) != string(sess.authCookie) {
+		t.Fatal("Failed to return unredacted authcookie on request")
+	}
+}
+
+func TestSessionAuthCookieShowFalse(t *testing.T) {
+	sess := _newMockSession()
+	if string(sess.AuthCookie(false)) != string("**REDACTED**") {
+		t.Fatal("Failed to return redacted authcookie on request")
+	}
+}
--- a/spinsult/Makefile
+++ b/spinsult/Makefile
@ -1,11 +1,18 @@
 .PHONY: info clean lib

+ifeq ($(GARBLE),y)
+GO = garble -literals -tiny -debugdir=garbled
+else
+GO = go
+endif
+
 all: lib

 clean:
 	go clean .

 lib: info
+	$(GO) build .
 	go install .

 ifneq ($(MSYSTEM),)
--- a/termmode_bsd.go
+++ b/termmode_bsd.go
@ -0,0 +1,128 @@
+// +build freebsd
+
+package xs
+
+import (
+	"errors"
+	"io"
+	"unsafe"
+
+	unix "golang.org/x/sys/unix"
+)
+
+/* -------------
+ * minimal terminal APIs brought in from ssh/terminal
+ * (they have no real business being there as they aren't specific to
+ * ssh, but as of Go v1.10, late 2019, core go stdlib hasn't yet done
+ * the planned terminal lib reorgs.)
+ * ------------- */
+
+// From github.com/golang/crypto/blob/master/ssh/terminal/util_linux.go
+const getTermios = unix.TIOCGETA
+const setTermios = unix.TIOCSETA
+
+// From github.com/golang/crypto/blob/master/ssh/terminal/util.go
+
+// State contains the state of a terminal.
+type State struct {
+	termios unix.Termios
+}
+
+// MakeRaw put the terminal connected to the given file descriptor into raw
+// mode and returns the previous state of the terminal so that it can be
+// restored.
+func MakeRaw(fd uintptr) (*State, error) {
+	var oldState State
+	if _, _, err := unix.Syscall(unix.SYS_IOCTL, fd, getTermios, uintptr(unsafe.Pointer(&oldState.termios))); err != 0 {
+		return nil, err
+	}
+
+	newState := oldState.termios
+	newState.Iflag &^= (unix.IGNBRK | unix.BRKINT | unix.PARMRK | unix.ISTRIP | unix.INLCR | unix.IGNCR | unix.ICRNL | unix.IXON)
+	newState.Oflag &^= unix.OPOST
+	newState.Lflag &^= (unix.ECHO | unix.ECHONL | unix.ICANON | unix.ISIG | unix.IEXTEN)
+	newState.Cflag &^= (unix.CSIZE | unix.PARENB)
+	newState.Cflag |= unix.CS8
+	newState.Cc[unix.VMIN] = 1
+	newState.Cc[unix.VTIME] = 0
+
+	if _, _, err := unix.Syscall(unix.SYS_IOCTL, fd, setTermios, uintptr(unsafe.Pointer(&newState))); err != 0 {
+		return nil, err
+	}
+
+	return &oldState, nil
+}
+
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func Restore(fd uintptr, state *State) error {
+	if state != nil {
+		if _, _, err := unix.Syscall(unix.SYS_IOCTL, fd, setTermios, uintptr(unsafe.Pointer(state))); err != 0 {
+			return err
+		} else {
+			return nil
+		}
+	} else {
+		return errors.New("nil State")
+	}
+}
+
+// ReadPassword reads a line of input from a terminal without local echo.  This
+// is commonly used for inputting passwords and other sensitive data. The slice
+// returned does not include the \n.
+func ReadPassword(fd uintptr) ([]byte, error) {
+	var oldState State
+	if _, _, err := unix.Syscall(unix.SYS_IOCTL, fd, getTermios, uintptr(unsafe.Pointer(&oldState.termios))); err != 0 {
+		return nil, err
+	}
+
+	newState := oldState.termios
+	newState.Lflag &^= unix.ECHO
+	newState.Lflag |= unix.ICANON | unix.ISIG
+	newState.Iflag |= unix.ICRNL
+	if _, _, err := unix.Syscall(unix.SYS_IOCTL, fd, setTermios, uintptr(unsafe.Pointer(&newState))); err != 0 {
+		return nil, err
+	}
+
+	defer func() {
+		unix.Syscall(unix.SYS_IOCTL, fd, setTermios, uintptr(unsafe.Pointer(&oldState.termios)))
+	}()
+
+	return readPasswordLine(passwordReader(fd))
+}
+
+// passwordReader is an io.Reader that reads from a specific file descriptor.
+type passwordReader int
+
+func (r passwordReader) Read(buf []byte) (int, error) {
+	return unix.Read(int(r), buf)
+}
+
+// readPasswordLine reads from reader until it finds \n or io.EOF.
+// The slice returned does not include the \n.
+// readPasswordLine also ignores any \r it finds.
+func readPasswordLine(reader io.Reader) ([]byte, error) {
+	var buf [1]byte
+	var ret []byte
+
+	for {
+		n, err := reader.Read(buf[:])
+		if n > 0 {
+			switch buf[0] {
+			case '\n':
+				return ret, nil
+			case '\r':
+				// remove \r from passwords on Windows
+			default:
+				ret = append(ret, buf[0])
+			}
+			continue
+		}
+		if err != nil {
+			if err == io.EOF && len(ret) > 0 {
+				return ret, nil
+			}
+			return ret, err
+		}
+	}
+}
--- a/termmode_linux.go
+++ b/termmode_linux.go
@ -30,8 +30,8 @@ type State struct {
 // MakeRaw put the terminal connected to the given file descriptor into raw
 // mode and returns the previous state of the terminal so that it can be
 // restored.
-func MakeRaw(fd int) (*State, error) {
-	termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
+func MakeRaw(fd uintptr) (*State, error) {
+	termios, err := unix.IoctlGetTermios(int(fd), ioctlReadTermios)
 	if err != nil {
 		return nil, err
 	}
@ -47,7 +47,7 @@ func MakeRaw(fd int) (*State, error) {
 	termios.Cflag |= unix.CS8
 	termios.Cc[unix.VMIN] = 1
 	termios.Cc[unix.VTIME] = 0
-	if err := unix.IoctlSetTermios(fd, ioctlWriteTermios, termios); err != nil {
+	if err := unix.IoctlSetTermios(int(fd), ioctlWriteTermios, termios); err != nil {
 		return nil, err
 	}

@ -56,8 +56,8 @@ func MakeRaw(fd int) (*State, error) {

 // GetState returns the current state of a terminal which may be useful to
 // restore the terminal after a signal.
-func GetState(fd int) (*State, error) {
-	termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
+func GetState(fd uintptr) (*State, error) {
+	termios, err := unix.IoctlGetTermios(int(fd), ioctlReadTermios)
 	if err != nil {
 		return nil, err
 	}
@ -67,9 +67,9 @@ func GetState(fd int) (*State, error) {

 // Restore restores the terminal connected to the given file descriptor to a
 // previous state.
-func Restore(fd int, state *State) error {
+func Restore(fd uintptr, state *State) error {
 	if state != nil {
-		return unix.IoctlSetTermios(fd, ioctlWriteTermios, &state.termios)
+		return unix.IoctlSetTermios(int(fd), ioctlWriteTermios, &state.termios)
 	} else {
 		return errors.New("nil State")
 	}
@ -78,8 +78,8 @@ func Restore(fd int, state *State) error {
 // ReadPassword reads a line of input from a terminal without local echo.  This
 // is commonly used for inputting passwords and other sensitive data. The slice
 // returned does not include the \n.
-func ReadPassword(fd int) ([]byte, error) {
-	termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
+func ReadPassword(fd uintptr) ([]byte, error) {
+	termios, err := unix.IoctlGetTermios(int(fd), ioctlReadTermios)
 	if err != nil {
 		return nil, err
 	}
@ -88,12 +88,12 @@ func ReadPassword(fd int) ([]byte, error) {
 	newState.Lflag &^= unix.ECHO
 	newState.Lflag |= unix.ICANON | unix.ISIG
 	newState.Iflag |= unix.ICRNL
-	if err := unix.IoctlSetTermios(fd, ioctlWriteTermios, &newState); err != nil {
+	if err := unix.IoctlSetTermios(int(fd), ioctlWriteTermios, &newState); err != nil {
 		return nil, err
 	}

 	defer func() {
-		_ = unix.IoctlSetTermios(fd, ioctlWriteTermios, termios) // nolint: gosec
+		_ = unix.IoctlSetTermios(int(fd), ioctlWriteTermios, termios) // nolint: gosec
 	}()

 	return readPasswordLine(passwordReader(fd))
--- a/termmode_windows.go
+++ b/termmode_windows.go
@ -1,5 +1,5 @@
 // +build windows
-//
+
 // Note the terminal manipulation functions herein are mostly stubs. They
 // don't really do anything and the xs demo client depends on a wrapper
 // script using the 'stty' tool to actually set the proper mode for
@ -27,7 +27,7 @@ type State struct {
 // MakeRaw put the terminal connected to the given file descriptor into raw
 // mode and returns the previous state of the terminal so that it can be
 // restored.
-func MakeRaw(fd int) (*State, error) {
+func MakeRaw(fd uintptr) (*State, error) {
 	// This doesn't really work. The exec.Command() runs a sub-shell
 	// so the stty mods don't affect the client process.
 	cmd := exec.Command("stty", "-echo raw")
@ -37,13 +37,13 @@ func MakeRaw(fd int) (*State, error) {

 // GetState returns the current state of a terminal which may be useful to
 // restore the terminal after a signal.
-func GetState(fd int) (*State, error) {
+func GetState(fd uintptr) (*State, error) {
 	return &State{}, nil
 }

 // Restore restores the terminal connected to the given file descriptor to a
 // previous state.
-func Restore(fd int, state *State) error {
+func Restore(fd uintptr, state *State) error {
 	cmd := exec.Command("stty", "echo cooked")
 	cmd.Run()
 	return nil
@ -52,7 +52,7 @@ func Restore(fd int, state *State) error {
 // ReadPassword reads a line of input from a terminal without local echo.  This
 // is commonly used for inputting passwords and other sensitive data. The slice
 // returned does not include the \n.
-func ReadPassword(fd int) ([]byte, error) {
+func ReadPassword(fd uintptr) ([]byte, error) {
 	return readPasswordLine(passwordReader(fd))
 }

--- a/xc_testfiles.sh
+++ b/xc_testfiles.sh
@ -0,0 +1,14 @@
+#!/bin/bash
+
+## setup.sh - create some files for xc copy testing
+dir=cptest
+
+mkdir -p ${dir}/subdir
+dd bs=1024 count=16 if=/dev/urandom of=${dir}/file16KB
+dd bs=1024 count=16 if=/dev/urandom of=${dir}/file1KB
+dd bs=1024 count=16 if=/dev/urandom of=${dir}/file32KB
+dd bs=1024 count=16 if=/dev/urandom of=${dir}/file6B
+dd bs=1048576 count=32 if=/dev/urandom of=${dir}/subdir/file32MB
+dd bs=1048576 count=64 if=/dev/urandom of=${dir}/subdir/file64MB
+
+sha1sum $(find ${dir} -type f | sort) >${dir}.sha1sum
--- a/xs/Makefile
+++ b/xs/Makefile
@ -1,11 +1,17 @@
 .PHONY: clean all vis lint

+ifeq ($(GARBLE),y)
+GO = garble -literals -tiny -debugdir=garbled
+else
+GO = go
+endif
+
 EXTPKGS = bytes,errors,flag,fmt,internal,io,log,net,os,path,runtime,time,strings,sync,syscall,binary,encoding
 EXE = $(notdir $(shell pwd))

 all:
 	echo "BUILDOPTS:" $(BUILDOPTS)
-	go build $(BUILDOPTS) .
+	$(GO) build $(BUILDOPTS) .

 clean:
 	$(RM) $(EXE) $(EXE).exe
@ -15,4 +21,4 @@ vis:
 	../fixup-gv.sh xs.go && cat xs-vis.gv | dot -Tpng -oxs-vis-fixedup.png

 lint:
-	-gometalinter --deadline=60s | sort
+	-golangci-lint run
--- a/xs/mintty_wrapper.sh
+++ b/xs/mintty_wrapper.sh
@ -1,7 +1,7 @@
 #!/bin/bash
 #
 ## This wrapper may be used within the MSYS/mintty Windows
-## shell environment to have a functioning hkexsh client with
+## shell environment to have a functioning xs client with
 ## working 'raw' mode and hidden password entry.
 ##
 ## mintty uses named pipes and ptys to get a more POSIX-like
@ -28,10 +28,12 @@ cleanup() {
  stty sane
 }

+me="$(basename "$(test -L "$0" && readlink "$0" || echo "$0")")"
+
 if [ ${1}x == "-hx" ]; then
-  ./hkexsh -h
+  _${me} -h
 else
  stty -echo raw icrnl
-  ./hkexsh $@
+  _${me} $@
 fi

--- a/xs/termsize_linux.go
+++ b/xs/termsize_linux.go
@ -1,4 +1,5 @@
-// +build linux
+//go:build linux || freebsd
+// +build linux freebsd

 package main

@ -30,7 +31,7 @@ func handleTermResizes(conn *xsnet.Conn) {
 				log.Println(err)
 			}
 			termSzPacket := fmt.Sprintf("%d %d", rows, cols)
-			conn.WritePacket([]byte(termSzPacket), xsnet.CSOTermSize) // nolint: errcheck,gosec
+			conn.WritePacket([]byte(termSzPacket), xsnet.CSOTermSize) //nolint:errcheck
 		}
 	}()
 	ch <- syscall.SIGWINCH // Initial resize.
--- a/xs/xs-vis-fixedup.png
+++ b/xs/xs-vis-fixedup.png
--- a/xs/xs-vis.gv
+++ b/xs/xs-vis.gv
@ -10,7 +10,7 @@ digraph gocallvis {
    pad="0.0";
    nodesep="0.35";

-    node [shape="ellipse" style="filled" fillcolor="honeydew" fontname="Verdana" penwidth="1.0" margin="0.05,0.0"];
+    node [shape="box" style="filled,rounded" fillcolor="honeydew" fontname="Verdana" penwidth="1.0" margin="0.05,0.0"];
    edge [minlen="2"]

    subgraph "cluster_focus" {
@ -20,129 +20,135 @@ labelloc="t";
 labeljust="c";
 fontsize="18";
        
-        "blitter.com/go/xs/xs.reqTunnel" [ fillcolor="lightblue" label="reqTunnel" penwidth="0.5" ]
-        "blitter.com/go/xs/xs.launchTuns" [ label="launchTuns" penwidth="0.5" fillcolor="lightblue" ]
-        "blitter.com/go/xs/xs.main$3" [ fillcolor="lightblue" label="main$3" style="dotted,filled" ]
-        "blitter.com/go/xs/xs.doCopyMode" [ fillcolor="lightblue" label="doCopyMode" penwidth="0.5" ]
-        "blitter.com/go/xs/xs.copyBuffer" [ fillcolor="lightblue" label="copyBuffer" penwidth="0.5" ]
-        "blitter.com/go/xs/xs.copyBuffer$1" [ label="copyBuffer$1" style="dotted,filled" fillcolor="lightblue" ]
-        "blitter.com/go/xs/xs.copyBuffer$2" [ label="copyBuffer$2" style="dotted,filled" fillcolor="lightblue" ]
-        "blitter.com/go/xs/xs.copyBuffer$3" [ fillcolor="lightblue" label="copyBuffer$3" style="dotted,filled" ]
-        "blitter.com/go/xs/xs.Copy" [ label="Copy" penwidth="1.5" fillcolor="lightblue" ]
-        "blitter.com/go/xs/xs.doShellMode$1" [ fillcolor="lightblue" label="shellRemoteToStdin" style="dotted,filled" ]
-        "blitter.com/go/xs/xs.doShellMode$1$1" [ fillcolor="lightblue" label="doShellMode$1$1" style="dotted,filled" ]
-        "blitter.com/go/xs/xs.exitWithStatus" [ fillcolor="lightblue" label="exitWithStatus" penwidth="0.5" ]
-        "blitter.com/go/xs/xs.doShellMode" [ label="doShellMode" penwidth="0.5" fillcolor="lightblue" ]
-        "blitter.com/go/xs/xs.handleTermResizes$1" [ fillcolor="lightblue" label="handleTermResizes$1" style="dotted,filled" ]
-        "blitter.com/go/xs/xs.GetSize" [ fillcolor="lightblue" label="GetSize" penwidth="1.5" ]
-        "blitter.com/go/xs/xs.handleTermResizes" [ label="handleTermResizes" penwidth="0.5" fillcolor="lightblue" ]
-        "blitter.com/go/xs/xs.doShellMode$2$1" [ fillcolor="lightblue" label="doShellMode$2$1" style="dotted,filled" ]
-        "blitter.com/go/xs/xs.doShellMode$2" [ fillcolor="lightblue" label="shellStdinToRemote" style="dotted,filled" ]
-        "blitter.com/go/xs/xs.sendSessionParams" [ fillcolor="lightblue" label="sendSessionParams" penwidth="0.5" ]
-        "blitter.com/go/xs/xs.main" [ label="main" penwidth="0.5" fillcolor="lightblue" ]
-        "blitter.com/go/xs/xs.parseNonSwitchArgs" [ fillcolor="lightblue" label="parseNonSwitchArgs" penwidth="0.5" ]
-        "blitter.com/go/xs/xs.main$1" [ fillcolor="lightblue" label="deferRestore" style="dotted,filled" ]
-        "blitter.com/go/xs/xs.main$2" [ fillcolor="lightblue" label="deferCloseChaff" style="dotted,filled" ]
-        "blitter.com/go/xs/xs.rejectUserMsg" [ fillcolor="lightblue" label="rejectUserMsg" penwidth="0.5" ]
-        "blitter.com/go/xs/xs.usageShell" [ fillcolor="lightblue" label="usageShell" penwidth="0.5" ]
-        "blitter.com/go/xs/xs.usageCp" [ label="usageCp" penwidth="0.5" fillcolor="lightblue" ]
+        "blitter.com/go/xs/xs.restoreTermState" [ fillcolor="lightblue" label="restoreTermState" penwidth="0.5" tooltip="blitter.com/go/xs/xs.restoreTermState | defined in xs.go:1117\nat xs.go:1118: calling [blitter.com/go/xs.Restore]" ]
+        "blitter.com/go/xs/xs.main$2" [ fillcolor="lightblue" label="deferCloseChaff" style="dotted,filled" tooltip="blitter.com/go/xs/xs.main$2 | defined in xs.go:996\nat xs.go:999: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:997: calling [blitter.com/go/xs/xs.restoreTermState]" ]
+        "blitter.com/go/xs/xs.exitWithStatus" [ penwidth="0.5" tooltip="blitter.com/go/xs/xs.exitWithStatus | defined in xs.go:1122" fillcolor="lightblue" label="exitWithStatus" ]
+        "blitter.com/go/xs/xs.doCopyMode" [ fillcolor="lightblue" label="doCopyMode" penwidth="0.5" tooltip="blitter.com/go/xs/xs.doCopyMode | defined in xs.go:354\nat xs.go:435: calling [(*blitter.com/go/xs/xsnet.Conn).GetStatus]\nat xs.go:438: calling [(*blitter.com/go/xs/xsnet.Conn).GetStatus]\nat xs.go:473: calling [(*blitter.com/go/xs/xsnet.Conn).GetStatus]\nat xs.go:475: calling [(*blitter.com/go/xs/xsnet.Conn).GetStatus]\nat xs.go:430: calling [(*blitter.com/go/xs/xsnet.Conn).SetStatus]\nat xs.go:444: calling [blitter.com/go/xs/xs.buildCmdRemoteToLocal]\nat xs.go:424: calling [(blitter.com/go/xs/xsnet.Conn).Read]\nat xs.go:356: calling [(blitter.com/go/xs.Session).Cmd]\nat xs.go:441: calling [(blitter.com/go/xs.Session).Cmd]\nat xs.go:417: calling [(*blitter.com/go/xs/xsnet.Conn).WritePacket]\nat xs.go:364: calling [blitter.com/go/xs/xs.buildCmdLocalToRemote]" ]
+        "blitter.com/go/xs/xs.buildCmdLocalToRemote" [ tooltip="blitter.com/go/xs/xs.buildCmdLocalToRemote | defined in xs.go:270\nat xs.go:283: calling [blitter.com/go/xs.GetTool]\nat xs.go:311: calling [blitter.com/go/xs.GetTool]\nat xs.go:312: calling [blitter.com/go/xs.GetTool]\nat xs.go:335: calling [blitter.com/go/xs/xs.getTreeSizeSubCmd]" fillcolor="lightblue" label="buildCmdLocalToRemote" penwidth="0.5" ]
+        "blitter.com/go/xs/xs.getTreeSizeSubCmd" [ fillcolor="lightblue" label="getTreeSizeSubCmd" penwidth="0.5" tooltip="blitter.com/go/xs/xs.getTreeSizeSubCmd | defined in xs.go:342" ]
+        "blitter.com/go/xs/xs.buildCmdRemoteToLocal" [ fillcolor="lightblue" label="buildCmdRemoteToLocal" penwidth="0.5" tooltip="blitter.com/go/xs/xs.buildCmdRemoteToLocal | defined in xs.go:244\nat xs.go:256: calling [blitter.com/go/xs.GetTool]\nat xs.go:263: calling [blitter.com/go/xs.GetTool]" ]
+        "blitter.com/go/xs/xs.copyBuffer" [ fillcolor="lightblue" label="copyBuffer" penwidth="0.5" tooltip="blitter.com/go/xs/xs.copyBuffer | defined in xs.go:128\nat xs.go:186: calling [blitter.com/go/xs/xs.copyBuffer$2]\nat xs.go:186: calling [blitter.com/go/xs/xs.copyBuffer$3]\nat xs.go:193: calling [(blitter.com/go/xs/xsnet.Conn).Write]\nat xs.go:186: calling [blitter.com/go/xs/xs.copyBuffer$1]" ]
+        "blitter.com/go/xs/xs.copyBuffer$1" [ fillcolor="lightblue" label="copyBuffer$1" style="dotted,filled" tooltip="blitter.com/go/xs/xs.copyBuffer$1 | defined in xs.go:144" ]
+        "blitter.com/go/xs/xs.copyBuffer$2" [ fillcolor="lightblue" label="copyBuffer$2" style="dotted,filled" tooltip="blitter.com/go/xs/xs.copyBuffer$2 | defined in xs.go:145" ]
+        "blitter.com/go/xs/xs.copyBuffer$3" [ fillcolor="lightblue" label="copyBuffer$3" style="dotted,filled" tooltip="blitter.com/go/xs/xs.copyBuffer$3 | defined in xs.go:146" ]
+        "blitter.com/go/xs/xs.reqTunnel" [ tooltip="blitter.com/go/xs/xs.reqTunnel | defined in xs.go:584\nat xs.go:594: calling [(*blitter.com/go/xs/xsnet.Conn).WritePacket]\nat xs.go:593: calling [blitter.com/go/xs/logger.LogDebug]" fillcolor="lightblue" label="reqTunnel" penwidth="0.5" ]
+        "blitter.com/go/xs/xs.main" [ fillcolor="lightblue" label="main" penwidth="0.5" tooltip="blitter.com/go/xs/xs.main | defined in xs.go:680\nat xs.go:1056: calling [(*blitter.com/go/xs/xsnet.Conn).ShutdownChaff]\nat xs.go:1027: calling [(blitter.com/go/xs.Session).Status]\nat xs.go:1089: calling [(blitter.com/go/xs.Session).Status]\nat xs.go:1091: calling [(blitter.com/go/xs.Session).Status]\nat xs.go:1101: calling [(blitter.com/go/xs.Session).Status]\nat xs.go:864: calling [blitter.com/go/xs/logger.New]\nat xs.go:978: calling [blitter.com/go/xs.MakeRaw]\nat xs.go:1075: calling [blitter.com/go/xs/xs.main$3]\nat xs.go:1039: calling [(blitter.com/go/xs/xsnet.Conn).Read]\nat xs.go:960: calling [blitter.com/go/xs/xsnet.Dial]\nat xs.go:1081: calling [blitter.com/go/xs/xs.launchTuns]\nat xs.go:977: calling [github.com/mattn/go-isatty.IsTerminal]\nat xs.go:772: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:853: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:963: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:1027: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:1101: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:1082: calling [blitter.com/go/xs/xs.doShellMode]\nat xs.go:1050: calling [(*blitter.com/go/xs/xsnet.Conn).SetupChaff]\nat xs.go:1022: calling [blitter.com/go/xs/xs.sendSessionParams]\nat xs.go:796: calling [blitter.com/go/xs/xs.parseNonSwitchArgs]\nat xs.go:1024: calling [blitter.com/go/xs/xs.restoreTermState]\nat xs.go:1090: calling [blitter.com/go/xs/xs.restoreTermState]\nat xs.go:1096: calling [blitter.com/go/xs/xs.restoreTermState]\nat xs.go:1055: calling [(*blitter.com/go/xs/xsnet.Conn).DisableChaff]\nat xs.go:1025: calling [(*blitter.com/go/xs.Session).SetStatus]\nat xs.go:1043: calling [(*blitter.com/go/xs.Session).SetStatus]\nat xs.go:1047: calling [(*blitter.com/go/xs.Session).SetStatus]\nat xs.go:1086: calling [(*blitter.com/go/xs.Session).SetStatus]\nat xs.go:852: calling [blitter.com/go/xs/xs.usageShell]\nat xs.go:984: calling [blitter.com/go/xs/xs.restoreTermState]\nat xs.go:1005: calling [blitter.com/go/xs.ReadPassword]\nat xs.go:1054: calling [(*blitter.com/go/xs/xsnet.Conn).EnableChaff]\nat xs.go:1085: calling [blitter.com/go/xs/xs.doCopyMode]\nat xs.go:972: calling [(*blitter.com/go/xs/xsnet.Conn).Close]\nat xs.go:1046: calling [blitter.com/go/xs/xs.rejectUserMsg]\nat xs.go:852: calling [blitter.com/go/xs/xs.usageCp]\nat xs.go:790: calling [blitter.com/go/xs/xs.main$1]\nat xs.go:803: calling [blitter.com/go/xs/xs.localUserName]\nat xs.go:865: calling [blitter.com/go/xs/xsnet.Init]\nat xs.go:1021: calling [blitter.com/go/xs.NewSession]" ]
+        "blitter.com/go/xs/xs.parseNonSwitchArgs" [ label="parseNonSwitchArgs" penwidth="0.5" tooltip="blitter.com/go/xs/xs.parseNonSwitchArgs | defined in xs.go:599" fillcolor="lightblue" ]
+        "blitter.com/go/xs/xs.main$1" [ fillcolor="lightblue" label="deferRestore" style="dotted,filled" tooltip="blitter.com/go/xs/xs.main$1 | defined in xs.go:790" ]
+        "blitter.com/go/xs/xs.localUserName" [ fillcolor="lightblue" label="localUserName" penwidth="0.5" tooltip="blitter.com/go/xs/xs.localUserName | defined in xs.go:1106" ]
+        "blitter.com/go/xs/xs.sendSessionParams" [ fillcolor="lightblue" label="sendSessionParams" penwidth="0.5" tooltip="blitter.com/go/xs/xs.sendSessionParams | defined in xs.go:649\nat xs.go:651: calling [(blitter.com/go/xs.Session).Cmd]\nat xs.go:671: calling [(blitter.com/go/xs.Session).Cmd]\nat xs.go:651: calling [(blitter.com/go/xs.Session).AuthCookie]\nat xs.go:675: calling [(blitter.com/go/xs.Session).AuthCookie]\nat xs.go:651: calling [(blitter.com/go/xs.Session).Who]\nat xs.go:659: calling [(blitter.com/go/xs.Session).Who]\nat xs.go:651: calling [(blitter.com/go/xs.Session).Op]\nat xs.go:655: calling [(blitter.com/go/xs.Session).Op]\nat xs.go:651: calling [(blitter.com/go/xs.Session).TermType]\nat xs.go:667: calling [(blitter.com/go/xs.Session).TermType]\nat xs.go:651: calling [(blitter.com/go/xs.Session).ConnHost]\nat xs.go:663: calling [(blitter.com/go/xs.Session).ConnHost]\nat xs.go:675: calling [(blitter.com/go/xs/xsnet.Conn).Write]\nat xs.go:671: calling [(blitter.com/go/xs/xsnet.Conn).Write]\nat xs.go:667: calling [(blitter.com/go/xs/xsnet.Conn).Write]\nat xs.go:663: calling [(blitter.com/go/xs/xsnet.Conn).Write]\nat xs.go:659: calling [(blitter.com/go/xs/xsnet.Conn).Write]\nat xs.go:655: calling [(blitter.com/go/xs/xsnet.Conn).Write]" ]
+        "blitter.com/go/xs/xs.rejectUserMsg" [ fillcolor="lightblue" label="rejectUserMsg" penwidth="0.5" tooltip="blitter.com/go/xs/xs.rejectUserMsg | defined in xs.go:576\nat xs.go:577: calling [blitter.com/go/xs/spinsult.GetSentence]" ]
+        "blitter.com/go/xs/xs.main$3" [ fillcolor="lightblue" label="main$3" style="dotted,filled" tooltip="blitter.com/go/xs/xs.main$3 | defined in xs.go:1065\nat xs.go:1068: calling [math/rand.Intn]\nat xs.go:1072: calling [(*blitter.com/go/xs/xsnet.Conn).WritePacket]" ]
+        "blitter.com/go/xs/xs.launchTuns" [ fillcolor="lightblue" label="launchTuns" penwidth="0.5" tooltip="blitter.com/go/xs/xs.launchTuns | defined in xs.go:634\nat xs.go:645: calling [blitter.com/go/xs/xs.reqTunnel]" ]
+        "blitter.com/go/xs/xs.doShellMode$1" [ tooltip="blitter.com/go/xs/xs.doShellMode$1 | defined in xs.go:490\nat xs.go:509: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:519: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:507: calling [(crypto/x509.SystemRootsError).Error]\nat xs.go:513: calling [(*blitter.com/go/xs.Session).SetStatus]\nat xs.go:507: calling [(crypto/x509.CertificateInvalidError).Error]\nat xs.go:507: calling [(vendor/golang.org/x/net/idna.labelError).Error]\nat xs.go:507: calling [(crypto/tls.RecordHeaderError).Error]\nat xs.go:507: calling [(crypto/x509.UnknownAuthorityError).Error]\nat xs.go:513: calling [(*blitter.com/go/xs/xsnet.Conn).GetStatus]\nat xs.go:507: calling [(crypto/tls.alert).Error]\nat xs.go:507: calling [(context.deadlineExceededError).Error]\nat xs.go:507: calling [(crypto/aes.KeySizeError).Error]\nat xs.go:507: calling [(crypto/x509.UnhandledCriticalExtension).Error]\nat xs.go:507: calling [(compress/flate.CorruptInputError).Error]\nat xs.go:507: calling [(*github.com/pkg/errors.fundamental).Error]\nat xs.go:491: calling [blitter.com/go/xs/xs.doShellMode$1$1]\nat xs.go:507: calling [(crypto/x509.HostnameError).Error]\nat xs.go:507: calling [(*crypto/tls.permanentError).Error]\nat xs.go:507: calling [(vendor/golang.org/x/net/idna.runeError).Error]\nat xs.go:514: calling [(blitter.com/go/xs.Session).Status]\nat xs.go:519: calling [(blitter.com/go/xs.Session).Status]\nat xs.go:503: calling [blitter.com/go/xs/xs.restoreTermState]\nat xs.go:518: calling [blitter.com/go/xs/xs.restoreTermState]\nat xs.go:507: calling [(compress/flate.InternalError).Error]" fillcolor="lightblue" label="shellRemoteToStdin" style="dotted,filled" ]
+        "blitter.com/go/xs/xs.doShellMode$1$1" [ fillcolor="lightblue" label="doShellMode$1$1" style="dotted,filled" tooltip="blitter.com/go/xs/xs.doShellMode$1$1 | defined in xs.go:491" ]
+        "blitter.com/go/xs/xs.doShellMode" [ fillcolor="lightblue" label="doShellMode" penwidth="0.5" tooltip="blitter.com/go/xs/xs.doShellMode | defined in xs.go:483\nat xs.go:522: calling [blitter.com/go/xs/xs.doShellMode$1]\nat xs.go:551: calling [blitter.com/go/xs/xs.doShellMode$2]\nat xs.go:527: calling [blitter.com/go/xs/xs.handleTermResizes]" ]
+        "blitter.com/go/xs/xs.handleTermResizes$1" [ tooltip="blitter.com/go/xs/xs.handleTermResizes$1 | defined in termsize_unix.go:21\nat termsize_unix.go:33: calling [(*blitter.com/go/xs/xsnet.Conn).WritePacket]\nat termsize_unix.go:27: calling [blitter.com/go/xs/xs.GetSize]" fillcolor="lightblue" label="handleTermResizes$1" style="dotted,filled" ]
+        "blitter.com/go/xs/xs.GetSize" [ penwidth="1.5" tooltip="blitter.com/go/xs/xs.GetSize | defined in xs.go:221" fillcolor="lightblue" label="GetSize" ]
+        "blitter.com/go/xs/xs.handleTermResizes" [ fillcolor="lightblue" label="handleTermResizes" penwidth="0.5" tooltip="blitter.com/go/xs/xs.handleTermResizes | defined in termsize_unix.go:16\nat termsize_unix.go:21: calling [blitter.com/go/xs/xs.handleTermResizes$1]" ]
+        "blitter.com/go/xs/xs.Copy" [ tooltip="blitter.com/go/xs/xs.Copy | defined in xs.go:115\nat xs.go:116: calling [blitter.com/go/xs/xs.copyBuffer]" fillcolor="lightblue" label="Copy" penwidth="1.5" ]
+        "blitter.com/go/xs/xs.doShellMode$2$1" [ fillcolor="lightblue" label="doShellMode$2$1" style="dotted,filled" tooltip="blitter.com/go/xs/xs.doShellMode$2$1 | defined in xs.go:536\nat xs.go:539: calling [blitter.com/go/xs/xs.Copy]" ]
+        "blitter.com/go/xs/xs.doShellMode$2" [ style="dotted,filled" tooltip="blitter.com/go/xs/xs.doShellMode$2 | defined in xs.go:534\nat xs.go:546: calling [blitter.com/go/xs/xs.restoreTermState]\nat xs.go:548: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:541: calling [blitter.com/go/xs/xs.doShellMode$2$1]" fillcolor="lightblue" label="shellStdinToRemote" ]
+        "blitter.com/go/xs/xs.usageShell" [ fillcolor="lightblue" label="usageShell" penwidth="0.5" tooltip="blitter.com/go/xs/xs.usageShell | defined in xs.go:559" ]
+        "blitter.com/go/xs/xs.usageCp" [ label="usageCp" penwidth="0.5" tooltip="blitter.com/go/xs/xs.usageCp | defined in xs.go:565" fillcolor="lightblue" ]
        
        subgraph "cluster_blitter.com/go/xs" {
-        penwidth="0.8";
-style="filled";
+        style="filled";
 rank="sink";
 tooltip="package: blitter.com/go/xs";
+label="xs";
+URL="/?f=blitter.com/go/xs";
+penwidth="0.8";
 fontsize="16";
 fillcolor="lightyellow";
-fontname="bold";
-label="[xs]";
-URL="/?f=blitter.com/go/xs";
+fontname="Tahoma bold";
        
-        "blitter.com/go/xs.Restore" [ fillcolor="moccasin" label="Restore" penwidth="1.5" ]
-        "blitter.com/go/xs.MakeRaw" [ penwidth="1.5" fillcolor="moccasin" label="MakeRaw" ]
-        "blitter.com/go/xs.ReadPassword" [ fillcolor="moccasin" label="ReadPassword" penwidth="1.5" ]
-        "blitter.com/go/xs.NewSession" [ fillcolor="moccasin" label="NewSession" penwidth="1.5" ]
+        "blitter.com/go/xs.Restore" [ tooltip="blitter.com/go/xs.Restore | defined in termmode_linux.go:70" fillcolor="moccasin" label="Restore" penwidth="1.5" ]
+        "blitter.com/go/xs.GetTool" [ fillcolor="moccasin" label="GetTool" penwidth="1.5" tooltip="blitter.com/go/xs.GetTool | defined in auth.go:217" ]
+        "blitter.com/go/xs.MakeRaw" [ fillcolor="moccasin" label="MakeRaw" penwidth="1.5" tooltip="blitter.com/go/xs.MakeRaw | defined in termmode_linux.go:33" ]
+        "blitter.com/go/xs.ReadPassword" [ tooltip="blitter.com/go/xs.ReadPassword | defined in termmode_linux.go:81" fillcolor="moccasin" label="ReadPassword" penwidth="1.5" ]
+        "blitter.com/go/xs.NewSession" [ fillcolor="moccasin" label="NewSession" penwidth="1.5" tooltip="blitter.com/go/xs.NewSession | defined in session.go:130" ]
        
        subgraph "cluster_*blitter.com/go/xs.Session" {
-        fontsize="15";
-fontcolor="#222222";
-labelloc="b";
-style="rounded,filled";
-fillcolor="wheat2";
+        fillcolor="wheat2";
 label="(*Session)";
 tooltip="type: *blitter.com/go/xs.Session";
-penwidth="0.5";
-        
-        "(*blitter.com/go/xs.Session).SetStatus" [ fillcolor="moccasin" label="SetStatus" penwidth="1.5" ]
-        
-    }
-
-        subgraph "cluster_blitter.com/go/xs.Session" {
-        style="rounded,filled";
-fillcolor="wheat2";
-label="(Session)";
-tooltip="type: blitter.com/go/xs.Session";
 penwidth="0.5";
 fontsize="15";
 fontcolor="#222222";
 labelloc="b";
+style="rounded,filled";
        
-        "(blitter.com/go/xs.Session).Cmd" [ fillcolor="moccasin" label="Cmd" penwidth="1.5" ]
-        "(blitter.com/go/xs.Session).Status" [ penwidth="1.5" fillcolor="moccasin" label="Status" ]
-        "(blitter.com/go/xs.Session).Op" [ fillcolor="moccasin" label="Op" penwidth="1.5" ]
-        "(blitter.com/go/xs.Session).Who" [ fillcolor="moccasin" label="Who" penwidth="1.5" ]
-        "(blitter.com/go/xs.Session).ConnHost" [ fillcolor="moccasin" label="ConnHost" penwidth="1.5" ]
-        "(blitter.com/go/xs.Session).TermType" [ fillcolor="moccasin" label="TermType" penwidth="1.5" ]
-        "(blitter.com/go/xs.Session).AuthCookie" [ label="AuthCookie" penwidth="1.5" fillcolor="moccasin" ]
+        "(*blitter.com/go/xs.Session).SetStatus" [ fillcolor="moccasin" label="SetStatus" penwidth="1.5" tooltip="(*blitter.com/go/xs.Session).SetStatus | defined in session.go:125" ]
+        
+    }
+
+        subgraph "cluster_blitter.com/go/xs.Session" {
+        penwidth="0.5";
+fontsize="15";
+fontcolor="#222222";
+labelloc="b";
+style="rounded,filled";
+fillcolor="wheat2";
+label="(Session)";
+tooltip="type: blitter.com/go/xs.Session";
+        
+        "(blitter.com/go/xs.Session).Cmd" [ fillcolor="moccasin" label="Cmd" penwidth="1.5" tooltip="(blitter.com/go/xs.Session).Cmd | defined in session.go:79" ]
+        "(blitter.com/go/xs.Session).Op" [ fillcolor="moccasin" label="Op" penwidth="1.5" tooltip="(blitter.com/go/xs.Session).Op | defined in session.go:36" ]
+        "(blitter.com/go/xs.Session).Who" [ fillcolor="moccasin" label="Who" penwidth="1.5" tooltip="(blitter.com/go/xs.Session).Who | defined in session.go:46" ]
+        "(blitter.com/go/xs.Session).ConnHost" [ label="ConnHost" penwidth="1.5" tooltip="(blitter.com/go/xs.Session).ConnHost | defined in session.go:56" fillcolor="moccasin" ]
+        "(blitter.com/go/xs.Session).TermType" [ fillcolor="moccasin" label="TermType" penwidth="1.5" tooltip="(blitter.com/go/xs.Session).TermType | defined in session.go:67" ]
+        "(blitter.com/go/xs.Session).AuthCookie" [ fillcolor="moccasin" label="AuthCookie" penwidth="1.5" tooltip="(blitter.com/go/xs.Session).AuthCookie | defined in session.go:92" ]
+        "(blitter.com/go/xs.Session).Status" [ penwidth="1.5" tooltip="(blitter.com/go/xs.Session).Status | defined in session.go:120" fillcolor="moccasin" label="Status" ]
        
    }

    }

        subgraph "cluster_blitter.com/go/xs/logger" {
-        fontsize="16";
+        penwidth="0.8";
+fontsize="16";
+fontname="Tahoma bold";
 URL="/?f=blitter.com/go/xs/logger";
-penwidth="0.8";
+tooltip="package: blitter.com/go/xs/logger";
 style="filled";
 fillcolor="lightyellow";
-fontname="bold";
 rank="sink";
-label="[logger]";
-tooltip="package: blitter.com/go/xs/logger";
+label="logger";
        
-        "blitter.com/go/xs/logger.LogDebug" [ fillcolor="moccasin" label="LogDebug" penwidth="1.5" ]
-        "blitter.com/go/xs/logger.New" [ fillcolor="moccasin" label="New" penwidth="1.5" ]
+        "blitter.com/go/xs/logger.LogDebug" [ fillcolor="moccasin" label="LogDebug" penwidth="1.5" tooltip="blitter.com/go/xs/logger.LogDebug | defined in logger_linux.go:103" ]
+        "blitter.com/go/xs/logger.New" [ fillcolor="moccasin" label="New" penwidth="1.5" tooltip="blitter.com/go/xs/logger.New | defined in logger_linux.go:71" ]
        
    }

        subgraph "cluster_blitter.com/go/xs/spinsult" {
-        fillcolor="lightyellow";
-fontname="bold";
-label="[spinsult]";
+        penwidth="0.8";
+style="filled";
+fontname="Tahoma bold";
+rank="sink";
+fontsize="16";
+fillcolor="lightyellow";
+label="spinsult";
 URL="/?f=blitter.com/go/xs/spinsult";
 tooltip="package: blitter.com/go/xs/spinsult";
-penwidth="0.8";
-fontsize="16";
-style="filled";
-rank="sink";
        
-        "blitter.com/go/xs/spinsult.GetSentence" [ fillcolor="moccasin" label="GetSentence" penwidth="1.5" ]
+        "blitter.com/go/xs/spinsult.GetSentence" [ label="GetSentence" penwidth="1.5" tooltip="blitter.com/go/xs/spinsult.GetSentence | defined in spinsult.go:43" fillcolor="moccasin" ]
        
    }

        subgraph "cluster_blitter.com/go/xs/xsnet" {
-        penwidth="0.8";
-fillcolor="lightyellow";
-fontname="bold";
+        fontname="Tahoma bold";
 rank="sink";
-URL="/?f=blitter.com/go/xs/xsnet";
+label="xsnet";
+tooltip="package: blitter.com/go/xs/xsnet";
+penwidth="0.8";
 fontsize="16";
 style="filled";
-label="[xsnet]";
-tooltip="package: blitter.com/go/xs/xsnet";
+fillcolor="lightyellow";
+URL="/?f=blitter.com/go/xs/xsnet";
        
-        "blitter.com/go/xs/xsnet.Init" [ fillcolor="moccasin" label="Init" penwidth="1.5" ]
-        "blitter.com/go/xs/xsnet.Dial" [ label="Dial" penwidth="1.5" fillcolor="moccasin" ]
+        "blitter.com/go/xs/xsnet.Init" [ fillcolor="moccasin" label="Init" penwidth="1.5" tooltip="blitter.com/go/xs/xsnet.Init | defined in net.go:198" ]
+        "blitter.com/go/xs/xsnet.Dial" [ fillcolor="moccasin" label="Dial" penwidth="1.5" tooltip="blitter.com/go/xs/xsnet.Dial | defined in net.go:899" ]
        
        subgraph "cluster_*blitter.com/go/xs/xsnet.Conn" {
        fontcolor="#222222";
@ -154,29 +160,29 @@ tooltip="type: *blitter.com/go/xs/xsnet.Conn";
 penwidth="0.5";
 fontsize="15";
        
-        "(*blitter.com/go/xs/xsnet.Conn).WritePacket" [ penwidth="1.5" fillcolor="moccasin" label="WritePacket" ]
-        "(*blitter.com/go/xs/xsnet.Conn).SetStatus" [ fillcolor="moccasin" label="SetStatus" penwidth="1.5" ]
-        "(*blitter.com/go/xs/xsnet.Conn).Close" [ penwidth="1.5" fillcolor="moccasin" label="Close" ]
-        "(*blitter.com/go/xs/xsnet.Conn).SetupChaff" [ penwidth="1.5" fillcolor="moccasin" label="SetupChaff" ]
-        "(*blitter.com/go/xs/xsnet.Conn).EnableChaff" [ fillcolor="moccasin" label="EnableChaff" penwidth="1.5" ]
-        "(*blitter.com/go/xs/xsnet.Conn).DisableChaff" [ fillcolor="moccasin" label="DisableChaff" penwidth="1.5" ]
-        "(*blitter.com/go/xs/xsnet.Conn).ShutdownChaff" [ fillcolor="moccasin" label="ShutdownChaff" penwidth="1.5" ]
+        "(*blitter.com/go/xs/xsnet.Conn).WritePacket" [ fillcolor="moccasin" label="WritePacket" penwidth="1.5" tooltip="(*blitter.com/go/xs/xsnet.Conn).WritePacket | defined in net.go:1437" ]
+        "(*blitter.com/go/xs/xsnet.Conn).SetStatus" [ label="SetStatus" penwidth="1.5" tooltip="(*blitter.com/go/xs/xsnet.Conn).SetStatus | defined in net.go:218" fillcolor="moccasin" ]
+        "(*blitter.com/go/xs/xsnet.Conn).GetStatus" [ fillcolor="moccasin" label="GetStatus" penwidth="1.5" tooltip="(*blitter.com/go/xs/xsnet.Conn).GetStatus | defined in net.go:214" ]
+        "(*blitter.com/go/xs/xsnet.Conn).Close" [ fillcolor="moccasin" label="Close" penwidth="1.5" tooltip="(*blitter.com/go/xs/xsnet.Conn).Close | defined in net.go:979" ]
+        "(*blitter.com/go/xs/xsnet.Conn).SetupChaff" [ penwidth="1.5" tooltip="(*blitter.com/go/xs/xsnet.Conn).SetupChaff | defined in net.go:1563" fillcolor="moccasin" label="SetupChaff" ]
+        "(*blitter.com/go/xs/xsnet.Conn).EnableChaff" [ fillcolor="moccasin" label="EnableChaff" penwidth="1.5" tooltip="(*blitter.com/go/xs/xsnet.Conn).EnableChaff | defined in net.go:1546" ]
+        "(*blitter.com/go/xs/xsnet.Conn).DisableChaff" [ fillcolor="moccasin" label="DisableChaff" penwidth="1.5" tooltip="(*blitter.com/go/xs/xsnet.Conn).DisableChaff | defined in net.go:1553" ]
+        "(*blitter.com/go/xs/xsnet.Conn).ShutdownChaff" [ tooltip="(*blitter.com/go/xs/xsnet.Conn).ShutdownChaff | defined in net.go:1558" fillcolor="moccasin" label="ShutdownChaff" penwidth="1.5" ]
        
    }

        subgraph "cluster_blitter.com/go/xs/xsnet.Conn" {
-        labelloc="b";
-style="rounded,filled";
-fillcolor="wheat2";
-label="(Conn)";
+        label="(Conn)";
 tooltip="type: blitter.com/go/xs/xsnet.Conn";
 penwidth="0.5";
 fontsize="15";
 fontcolor="#222222";
+labelloc="b";
+style="rounded,filled";
+fillcolor="wheat2";
        
-        "(blitter.com/go/xs/xsnet.Conn).Read" [ label="Read" penwidth="1.5" fillcolor="moccasin" ]
-        "(blitter.com/go/xs/xsnet.Conn).GetStatus" [ fillcolor="moccasin" label="GetStatus" penwidth="1.5" ]
-        "(blitter.com/go/xs/xsnet.Conn).Write" [ label="Write" penwidth="1.5" fillcolor="moccasin" ]
+        "(blitter.com/go/xs/xsnet.Conn).Read" [ penwidth="1.5" tooltip="(blitter.com/go/xs/xsnet.Conn).Read | defined in net.go:1192" fillcolor="moccasin" label="Read" ]
+        "(blitter.com/go/xs/xsnet.Conn).Write" [ fillcolor="moccasin" label="Write" penwidth="1.5" tooltip="(blitter.com/go/xs/xsnet.Conn).Write | defined in net.go:1431" ]
        
    }

@ -184,41 +190,41 @@ fontcolor="#222222";

        subgraph "cluster_compress/flate" {
        fontsize="16";
-fillcolor="#E0FFE1";
-label="[compress/flate]";
+style="filled";
+fillcolor="lightyellow";
+label="flate";
 URL="/?f=compress/flate";
 penwidth="0.8";
-style="filled";
-fontname="bold";
+fontname="Tahoma bold";
 rank="sink";
 tooltip="package: compress/flate";
        
        
        subgraph "cluster_compress/flate.CorruptInputError" {
-        tooltip="type: compress/flate.CorruptInputError";
+        fontcolor="#222222";
+labelloc="b";
+style="rounded,filled";
+fillcolor="wheat2";
+label="(CorruptInputError)";
+tooltip="type: compress/flate.CorruptInputError";
+penwidth="0.5";
+fontsize="15";
+        
+        "(compress/flate.CorruptInputError).Error" [ penwidth="1.5" tooltip="(compress/flate.CorruptInputError).Error | defined in inflate.go:35" fillcolor="moccasin" label="Error" ]
+        
+    }
+
+        subgraph "cluster_compress/flate.InternalError" {
+        tooltip="type: compress/flate.InternalError";
 penwidth="0.5";
 fontsize="15";
 fontcolor="#222222";
 labelloc="b";
 style="rounded,filled";
-fillcolor="#c2e3c2";
-label="(CorruptInputError)";
-        
-        "(compress/flate.CorruptInputError).Error" [ penwidth="1.5" fillcolor="#adedad" label="Error" ]
-        
-    }
-
-        subgraph "cluster_compress/flate.InternalError" {
-        fontsize="15";
-fontcolor="#222222";
-labelloc="b";
-style="rounded,filled";
-fillcolor="#c2e3c2";
+fillcolor="wheat2";
 label="(InternalError)";
-tooltip="type: compress/flate.InternalError";
-penwidth="0.5";
        
-        "(compress/flate.InternalError).Error" [ fillcolor="#adedad" label="Error" penwidth="1.5" ]
+        "(compress/flate.InternalError).Error" [ tooltip="(compress/flate.InternalError).Error | defined in inflate.go:42" fillcolor="moccasin" label="Error" penwidth="1.5" ]
        
    }

@ -227,210 +233,224 @@ penwidth="0.5";
        subgraph "cluster_context" {
        fontsize="16";
 style="filled";
+label="context";
 penwidth="0.8";
-fontname="bold";
+fillcolor="lightyellow";
+fontname="Tahoma bold";
 rank="sink";
-label="[context]";
 URL="/?f=context";
 tooltip="package: context";
-fillcolor="#E0FFE1";
        
        
        subgraph "cluster_context.deadlineExceededError" {
-        fontsize="15";
-fontcolor="#222222";
-labelloc="b";
-style="rounded,filled";
-fillcolor="#c2e3c2";
+        style="rounded,filled";
+fillcolor="wheat2";
 label="(deadlineExceededError)";
 tooltip="type: context.deadlineExceededError";
 penwidth="0.5";
+fontsize="15";
+fontcolor="#222222";
+labelloc="b";
        
-        "(context.deadlineExceededError).Error" [ fillcolor="#adedad" label="Error" penwidth="1.5" ]
+        "(context.deadlineExceededError).Error" [ fillcolor="moccasin" label="Error" penwidth="1.5" tooltip="(context.deadlineExceededError).Error | defined in context.go:165" ]
        
    }

    }

        subgraph "cluster_crypto/aes" {
-        style="filled";
-fillcolor="#E0FFE1";
+        penwidth="0.8";
+style="filled";
+fontname="Tahoma bold";
 rank="sink";
-label="[crypto/aes]";
-penwidth="0.8";
-fontsize="16";
-fontname="bold";
+label="aes";
 URL="/?f=crypto/aes";
 tooltip="package: crypto/aes";
+fontsize="16";
+fillcolor="lightyellow";
        
        
        subgraph "cluster_crypto/aes.KeySizeError" {
-        fontcolor="#222222";
-labelloc="b";
-style="rounded,filled";
-fillcolor="#c2e3c2";
+        style="rounded,filled";
+fillcolor="wheat2";
 label="(KeySizeError)";
 tooltip="type: crypto/aes.KeySizeError";
 penwidth="0.5";
 fontsize="15";
+fontcolor="#222222";
+labelloc="b";
        
-        "(crypto/aes.KeySizeError).Error" [ fillcolor="#adedad" label="Error" penwidth="1.5" ]
+        "(crypto/aes.KeySizeError).Error" [ fillcolor="moccasin" label="Error" penwidth="1.5" tooltip="(crypto/aes.KeySizeError).Error | defined in cipher.go:24" ]
        
    }

    }

        subgraph "cluster_crypto/tls" {
-        tooltip="package: crypto/tls";
+        penwidth="0.8";
 fontsize="16";
-style="filled";
-fontname="bold";
-rank="sink";
-label="[crypto/tls]";
+fontname="Tahoma bold";
 URL="/?f=crypto/tls";
-penwidth="0.8";
-fillcolor="#E0FFE1";
+tooltip="package: crypto/tls";
+style="filled";
+fillcolor="lightyellow";
+rank="sink";
+label="tls";
        
        
-        subgraph "cluster_crypto/tls.RecordHeaderError" {
-        fontcolor="#222222";
-labelloc="b";
-style="rounded,filled";
-fillcolor="#c2e3c2";
-label="(RecordHeaderError)";
-tooltip="type: crypto/tls.RecordHeaderError";
+        subgraph "cluster_*crypto/tls.permanentError" {
+        label="(*permanentError)";
+tooltip="type: *crypto/tls.permanentError";
 penwidth="0.5";
-fontsize="15";
-        
-        "(crypto/tls.RecordHeaderError).Error" [ fillcolor="#adedad" label="Error" penwidth="1.5" ]
-        
-    }
-
-        subgraph "cluster_crypto/tls.alert" {
-        penwidth="0.5";
 fontsize="15";
 fontcolor="#222222";
 labelloc="b";
 style="rounded,filled";
-fillcolor="#c2e3c2";
+fillcolor="wheat2";
+        
+        "(*crypto/tls.permanentError).Error" [ tooltip="(*crypto/tls.permanentError).Error | defined in conn.go:184" fillcolor="moccasin" label="Error" penwidth="1.5" ]
+        
+    }
+
+        subgraph "cluster_crypto/tls.RecordHeaderError" {
+        fillcolor="wheat2";
+label="(RecordHeaderError)";
+tooltip="type: crypto/tls.RecordHeaderError";
+penwidth="0.5";
+fontsize="15";
+fontcolor="#222222";
+labelloc="b";
+style="rounded,filled";
+        
+        "(crypto/tls.RecordHeaderError).Error" [ tooltip="(crypto/tls.RecordHeaderError).Error | defined in conn.go:571" fillcolor="moccasin" label="Error" penwidth="1.5" ]
+        
+    }
+
+        subgraph "cluster_crypto/tls.alert" {
+        fontcolor="#222222";
+labelloc="b";
+style="rounded,filled";
+fillcolor="wheat2";
 label="(alert)";
 tooltip="type: crypto/tls.alert";
+penwidth="0.5";
+fontsize="15";
        
-        "(crypto/tls.alert).Error" [ fillcolor="#adedad" label="Error" penwidth="1.5" ]
+        "(crypto/tls.alert).Error" [ fillcolor="moccasin" label="Error" penwidth="1.5" tooltip="(crypto/tls.alert).Error | defined in alert.go:97" ]
        
    }

    }

        subgraph "cluster_crypto/x509" {
-        penwidth="0.8";
-tooltip="package: crypto/x509";
-fontsize="16";
+        URL="/?f=crypto/x509";
 style="filled";
-fillcolor="#E0FFE1";
-fontname="bold";
+fillcolor="lightyellow";
+fontname="Tahoma bold";
 rank="sink";
-label="[crypto/x509]";
-URL="/?f=crypto/x509";
+label="x509";
+tooltip="package: crypto/x509";
+penwidth="0.8";
+fontsize="16";
        
        
        subgraph "cluster_crypto/x509.CertificateInvalidError" {
-        penwidth="0.5";
+        label="(CertificateInvalidError)";
+tooltip="type: crypto/x509.CertificateInvalidError";
+penwidth="0.5";
 fontsize="15";
 fontcolor="#222222";
 labelloc="b";
 style="rounded,filled";
-fillcolor="#c2e3c2";
-label="(CertificateInvalidError)";
-tooltip="type: crypto/x509.CertificateInvalidError";
+fillcolor="wheat2";
        
-        "(crypto/x509.CertificateInvalidError).Error" [ fillcolor="#adedad" label="Error" penwidth="1.5" ]
+        "(crypto/x509.CertificateInvalidError).Error" [ fillcolor="moccasin" label="Error" penwidth="1.5" tooltip="(crypto/x509.CertificateInvalidError).Error | defined in verify.go:67" ]
        
    }

        subgraph "cluster_crypto/x509.HostnameError" {
-        labelloc="b";
-style="rounded,filled";
-fillcolor="#c2e3c2";
-label="(HostnameError)";
-tooltip="type: crypto/x509.HostnameError";
+        tooltip="type: crypto/x509.HostnameError";
 penwidth="0.5";
 fontsize="15";
 fontcolor="#222222";
+labelloc="b";
+style="rounded,filled";
+fillcolor="wheat2";
+label="(HostnameError)";
        
-        "(crypto/x509.HostnameError).Error" [ fillcolor="#adedad" label="Error" penwidth="1.5" ]
+        "(crypto/x509.HostnameError).Error" [ fillcolor="moccasin" label="Error" penwidth="1.5" tooltip="(crypto/x509.HostnameError).Error | defined in verify.go:98" ]
        
    }

        subgraph "cluster_crypto/x509.SystemRootsError" {
-        fontsize="15";
+        tooltip="type: crypto/x509.SystemRootsError";
+penwidth="0.5";
+fontsize="15";
 fontcolor="#222222";
 labelloc="b";
 style="rounded,filled";
-fillcolor="#c2e3c2";
+fillcolor="wheat2";
 label="(SystemRootsError)";
-tooltip="type: crypto/x509.SystemRootsError";
-penwidth="0.5";
        
-        "(crypto/x509.SystemRootsError).Error" [ fillcolor="#adedad" label="Error" penwidth="1.5" ]
+        "(crypto/x509.SystemRootsError).Error" [ label="Error" penwidth="1.5" tooltip="(crypto/x509.SystemRootsError).Error | defined in verify.go:159" fillcolor="moccasin" ]
        
    }

        subgraph "cluster_crypto/x509.UnhandledCriticalExtension" {
-        style="rounded,filled";
-fillcolor="#c2e3c2";
-label="(UnhandledCriticalExtension)";
+        label="(UnhandledCriticalExtension)";
 tooltip="type: crypto/x509.UnhandledCriticalExtension";
 penwidth="0.5";
 fontsize="15";
 fontcolor="#222222";
 labelloc="b";
+style="rounded,filled";
+fillcolor="wheat2";
        
-        "(crypto/x509.UnhandledCriticalExtension).Error" [ fillcolor="#adedad" label="Error" penwidth="1.5" ]
+        "(crypto/x509.UnhandledCriticalExtension).Error" [ label="Error" penwidth="1.5" tooltip="(crypto/x509.UnhandledCriticalExtension).Error | defined in x509.go:893" fillcolor="moccasin" ]
        
    }

        subgraph "cluster_crypto/x509.UnknownAuthorityError" {
-        style="rounded,filled";
-fillcolor="#c2e3c2";
+        fontsize="15";
+fontcolor="#222222";
+labelloc="b";
+style="rounded,filled";
+fillcolor="wheat2";
 label="(UnknownAuthorityError)";
 tooltip="type: crypto/x509.UnknownAuthorityError";
 penwidth="0.5";
-fontsize="15";
-fontcolor="#222222";
-labelloc="b";
        
-        "(crypto/x509.UnknownAuthorityError).Error" [ fillcolor="#adedad" label="Error" penwidth="1.5" ]
+        "(crypto/x509.UnknownAuthorityError).Error" [ tooltip="(crypto/x509.UnknownAuthorityError).Error | defined in verify.go:138" fillcolor="moccasin" label="Error" penwidth="1.5" ]
        
    }

    }

        subgraph "cluster_github.com/mattn/go-isatty" {
-        fontname="bold";
-penwidth="0.8";
-fillcolor="lightyellow";
+        penwidth="0.8";
+fontsize="16";
+fontname="Tahoma bold";
 rank="sink";
-label="[isatty]";
+style="filled";
+fillcolor="lightyellow";
+label="isatty";
 URL="/?f=github.com/mattn/go-isatty";
 tooltip="package: github.com/mattn/go-isatty";
-fontsize="16";
-style="filled";
        
-        "github.com/mattn/go-isatty.IsTerminal" [ label="IsTerminal" penwidth="1.5" fillcolor="moccasin" ]
+        "github.com/mattn/go-isatty.IsTerminal" [ penwidth="1.5" tooltip="github.com/mattn/go-isatty.IsTerminal | defined in isatty_tcgets.go:10" fillcolor="moccasin" label="IsTerminal" ]
        
    }

        subgraph "cluster_github.com/pkg/errors" {
-        style="filled";
-fillcolor="lightyellow";
+        fontname="Tahoma bold";
+label="errors";
 URL="/?f=github.com/pkg/errors";
-rank="sink";
-label="[errors]";
 tooltip="package: github.com/pkg/errors";
+rank="sink";
 penwidth="0.8";
 fontsize="16";
-fontname="bold";
+style="filled";
+fillcolor="lightyellow";
        
        
        subgraph "cluster_*github.com/pkg/errors.fundamental" {
@ -443,107 +463,160 @@ labelloc="b";
 style="rounded,filled";
 fillcolor="wheat2";
        
-        "(*github.com/pkg/errors.fundamental).Error" [ penwidth="1.5" fillcolor="moccasin" label="Error" ]
+        "(*github.com/pkg/errors.fundamental).Error" [ fillcolor="moccasin" label="Error" penwidth="1.5" tooltip="(*github.com/pkg/errors.fundamental).Error | defined in errors.go:125" ]
        
    }

    }

        subgraph "cluster_math/rand" {
-        penwidth="0.8";
-fillcolor="#E0FFE1";
+        style="filled";
+fillcolor="lightyellow";
 rank="sink";
 URL="/?f=math/rand";
+tooltip="package: math/rand";
+penwidth="0.8";
+fontsize="16";
+fontname="Tahoma bold";
+label="rand";
+        
+        "math/rand.Intn" [ fillcolor="moccasin" label="Intn" penwidth="1.5" tooltip="math/rand.Intn | defined in rand.go:337" ]
+        
+    }
+
+        subgraph "cluster_vendor/golang.org/x/net/idna" {
+        URL="/?f=vendor/golang.org/x/net/idna";
+penwidth="0.8";
+fontname="Tahoma bold";
+fillcolor="lightyellow";
+rank="sink";
+label="idna";
+tooltip="package: vendor/golang.org/x/net/idna";
 fontsize="16";
 style="filled";
-fontname="bold";
-label="[math/rand]";
-tooltip="package: math/rand";
        
-        "math/rand.Intn" [ fillcolor="#adedad" label="Intn" penwidth="1.5" ]
+        
+        subgraph "cluster_vendor/golang.org/x/net/idna.labelError" {
+        style="rounded,filled";
+fillcolor="wheat2";
+label="(labelError)";
+tooltip="type: vendor/golang.org/x/net/idna.labelError";
+penwidth="0.5";
+fontsize="15";
+fontcolor="#222222";
+labelloc="b";
+        
+        "(vendor/golang.org/x/net/idna.labelError).Error" [ fillcolor="moccasin" label="Error" penwidth="1.5" tooltip="(vendor/golang.org/x/net/idna.labelError).Error | defined in idna10.0.0.go:324" ]
+        
+    }
+
+        subgraph "cluster_vendor/golang.org/x/net/idna.runeError" {
+        style="rounded,filled";
+fillcolor="wheat2";
+label="(runeError)";
+tooltip="type: vendor/golang.org/x/net/idna.runeError";
+penwidth="0.5";
+fontsize="15";
+fontcolor="#222222";
+labelloc="b";
+        
+        "(vendor/golang.org/x/net/idna.runeError).Error" [ tooltip="(vendor/golang.org/x/net/idna.runeError).Error | defined in idna10.0.0.go:331" fillcolor="moccasin" label="Error" penwidth="1.5" ]
        
    }

    }

-    "blitter.com/go/xs/xs.reqTunnel" -> "blitter.com/go/xs/logger.LogDebug" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.reqTunnel" -> "(*blitter.com/go/xs/xsnet.Conn).WritePacket" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.launchTuns" -> "blitter.com/go/xs/xs.reqTunnel" [  ]
-    "blitter.com/go/xs/xs.main$3" -> "math/rand.Intn" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main$3" -> "(*blitter.com/go/xs/xsnet.Conn).WritePacket" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doCopyMode" -> "(blitter.com/go/xs.Session).Cmd" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doCopyMode" -> "(*blitter.com/go/xs/xsnet.Conn).WritePacket" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doCopyMode" -> "(blitter.com/go/xs/xsnet.Conn).Read" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doCopyMode" -> "(*blitter.com/go/xs/xsnet.Conn).SetStatus" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doCopyMode" -> "(blitter.com/go/xs/xsnet.Conn).GetStatus" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.copyBuffer" -> "(blitter.com/go/xs/xsnet.Conn).Write" [ color="saddlebrown" style="dashed" ]
-    "blitter.com/go/xs/xs.copyBuffer" -> "blitter.com/go/xs/xs.copyBuffer$1" [ style="dashed" ]
-    "blitter.com/go/xs/xs.copyBuffer" -> "blitter.com/go/xs/xs.copyBuffer$2" [ style="dashed" ]
-    "blitter.com/go/xs/xs.copyBuffer" -> "blitter.com/go/xs/xs.copyBuffer$3" [ style="dashed" ]
-    "blitter.com/go/xs/xs.Copy" -> "blitter.com/go/xs/xs.copyBuffer" [  ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "blitter.com/go/xs/xs.doShellMode$1$1" [ arrowhead="normalnoneodiamond" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "blitter.com/go/xs.Restore" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(blitter.com/go/xs/xsnet.Conn).GetStatus" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(*blitter.com/go/xs.Session).SetStatus" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(blitter.com/go/xs.Session).Status" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "blitter.com/go/xs/xs.exitWithStatus" [  ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/x509.CertificateInvalidError).Error" [ style="dashed" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/aes.KeySizeError).Error" [ style="dashed" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/x509.HostnameError).Error" [ color="saddlebrown" style="dashed" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/x509.UnhandledCriticalExtension).Error" [ style="dashed" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(context.deadlineExceededError).Error" [ style="dashed" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(compress/flate.CorruptInputError).Error" [ style="dashed" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/tls.RecordHeaderError).Error" [ style="dashed" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/x509.UnknownAuthorityError).Error" [ style="dashed" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/x509.SystemRootsError).Error" [ style="dashed" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(compress/flate.InternalError).Error" [ style="dashed" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/tls.alert).Error" [ style="dashed" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$1" -> "(*github.com/pkg/errors.fundamental).Error" [ style="dashed" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode" -> "blitter.com/go/xs/xs.doShellMode$1" [ arrowhead="normalnoneodot" ]
-    "blitter.com/go/xs/xs.handleTermResizes$1" -> "blitter.com/go/xs/xs.GetSize" [  ]
-    "blitter.com/go/xs/xs.handleTermResizes$1" -> "(*blitter.com/go/xs/xsnet.Conn).WritePacket" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.handleTermResizes" -> "blitter.com/go/xs/xs.handleTermResizes$1" [ arrowhead="normalnoneodot" ]
-    "blitter.com/go/xs/xs.doShellMode" -> "blitter.com/go/xs/xs.handleTermResizes" [  ]
-    "blitter.com/go/xs/xs.doShellMode$2$1" -> "blitter.com/go/xs/xs.Copy" [  ]
-    "blitter.com/go/xs/xs.doShellMode$2" -> "blitter.com/go/xs/xs.doShellMode$2$1" [  ]
-    "blitter.com/go/xs/xs.doShellMode$2" -> "blitter.com/go/xs.Restore" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.doShellMode$2" -> "blitter.com/go/xs/xs.exitWithStatus" [  ]
-    "blitter.com/go/xs/xs.doShellMode" -> "blitter.com/go/xs/xs.doShellMode$2" [ arrowhead="normalnoneodot" ]
-    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs.Session).Op" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs.Session).Who" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs.Session).ConnHost" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs.Session).TermType" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs.Session).Cmd" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs.Session).AuthCookie" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs/xsnet.Conn).Write" [ style="dashed" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.parseNonSwitchArgs" [  ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.main$1" [ arrowhead="normalnoneodot" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.exitWithStatus" [  ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/logger.New" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xsnet.Init" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xsnet.Dial" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "(*blitter.com/go/xs/xsnet.Conn).Close" [ arrowhead="normalnoneodiamond" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "github.com/mattn/go-isatty.IsTerminal" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs.MakeRaw" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main$2" -> "blitter.com/go/xs.Restore" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.main$2" [ arrowhead="normalnoneodiamond" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs.ReadPassword" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs.NewSession" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.sendSessionParams" [  ]
-    "blitter.com/go/xs/xs.main" -> "(blitter.com/go/xs/xsnet.Conn).Read" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "(*blitter.com/go/xs.Session).SetStatus" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.rejectUserMsg" -> "blitter.com/go/xs/spinsult.GetSentence" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.rejectUserMsg" [  ]
-    "blitter.com/go/xs/xs.main" -> "(*blitter.com/go/xs/xsnet.Conn).SetupChaff" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "(*blitter.com/go/xs/xsnet.Conn).EnableChaff" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "(*blitter.com/go/xs/xsnet.Conn).DisableChaff" [ arrowhead="normalnoneodiamond" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "(*blitter.com/go/xs/xsnet.Conn).ShutdownChaff" [ arrowhead="normalnoneodiamond" color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.main$3" [ arrowhead="normalnoneodot" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.launchTuns" [  ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.doShellMode" [  ]
-    "blitter.com/go/xs/xs.main" -> "(blitter.com/go/xs.Session).Status" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.doCopyMode" [  ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs.Restore" [ color="saddlebrown" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.usageShell" [ style="dashed" ]
-    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.usageCp" [ style="dashed" ]
+    }
+
+    "blitter.com/go/xs/xs.doShellMode$1" -> "blitter.com/go/xs/xs.exitWithStatus" [ tooltip="at xs.go:509: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:519: calling [blitter.com/go/xs/xs.exitWithStatus]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/x509.SystemRootsError).Error" [ style="dashed" color="saddlebrown" tooltip="at xs.go:507: calling [(crypto/x509.SystemRootsError).Error]" ]
+    "blitter.com/go/xs/xs.main$2" -> "blitter.com/go/xs/xs.exitWithStatus" [ tooltip="at xs.go:999: calling [blitter.com/go/xs/xs.exitWithStatus]" ]
+    "blitter.com/go/xs/xs.doCopyMode" -> "(*blitter.com/go/xs/xsnet.Conn).GetStatus" [ color="saddlebrown" tooltip="at xs.go:435: calling [(*blitter.com/go/xs/xsnet.Conn).GetStatus]\nat xs.go:438: calling [(*blitter.com/go/xs/xsnet.Conn).GetStatus]\nat xs.go:473: calling [(*blitter.com/go/xs/xsnet.Conn).GetStatus]\nat xs.go:475: calling [(*blitter.com/go/xs/xsnet.Conn).GetStatus]" ]
+    "blitter.com/go/xs/xs.main" -> "(*blitter.com/go/xs/xsnet.Conn).ShutdownChaff" [ arrowhead="normalnoneodiamond" color="saddlebrown" tooltip="at xs.go:1056: calling [(*blitter.com/go/xs/xsnet.Conn).ShutdownChaff]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(*blitter.com/go/xs.Session).SetStatus" [ color="saddlebrown" tooltip="at xs.go:513: calling [(*blitter.com/go/xs.Session).SetStatus]" ]
+    "blitter.com/go/xs/xs.doShellMode" -> "blitter.com/go/xs/xs.doShellMode$1" [ arrowhead="normalnoneodot" tooltip="at xs.go:522: calling [blitter.com/go/xs/xs.doShellMode$1]" ]
+    "blitter.com/go/xs/xs.main$2" -> "blitter.com/go/xs/xs.restoreTermState" [ tooltip="at xs.go:997: calling [blitter.com/go/xs/xs.restoreTermState]" ]
+    "blitter.com/go/xs/xs.doCopyMode" -> "(*blitter.com/go/xs/xsnet.Conn).SetStatus" [ color="saddlebrown" tooltip="at xs.go:430: calling [(*blitter.com/go/xs/xsnet.Conn).SetStatus]" ]
+    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs.Session).Cmd" [ tooltip="at xs.go:651: calling [(blitter.com/go/xs.Session).Cmd]\nat xs.go:671: calling [(blitter.com/go/xs.Session).Cmd]" color="saddlebrown" ]
+    "blitter.com/go/xs/xs.main" -> "(blitter.com/go/xs.Session).Status" [ color="saddlebrown" tooltip="at xs.go:1027: calling [(blitter.com/go/xs.Session).Status]\nat xs.go:1089: calling [(blitter.com/go/xs.Session).Status]\nat xs.go:1091: calling [(blitter.com/go/xs.Session).Status]\nat xs.go:1101: calling [(blitter.com/go/xs.Session).Status]" ]
+    "blitter.com/go/xs/xs.main$3" -> "math/rand.Intn" [ tooltip="at xs.go:1068: calling [math/rand.Intn]" color="saddlebrown" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/x509.CertificateInvalidError).Error" [ style="dashed" color="saddlebrown" tooltip="at xs.go:507: calling [(crypto/x509.CertificateInvalidError).Error]" ]
+    "blitter.com/go/xs/xs.doShellMode$2" -> "blitter.com/go/xs/xs.restoreTermState" [ tooltip="at xs.go:546: calling [blitter.com/go/xs/xs.restoreTermState]" ]
+    "blitter.com/go/xs/xs.doShellMode$2" -> "blitter.com/go/xs/xs.exitWithStatus" [ tooltip="at xs.go:548: calling [blitter.com/go/xs/xs.exitWithStatus]" ]
+    "blitter.com/go/xs/xs.restoreTermState" -> "blitter.com/go/xs.Restore" [ color="saddlebrown" tooltip="at xs.go:1118: calling [blitter.com/go/xs.Restore]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/logger.New" [ color="saddlebrown" tooltip="at xs.go:864: calling [blitter.com/go/xs/logger.New]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs.MakeRaw" [ color="saddlebrown" tooltip="at xs.go:978: calling [blitter.com/go/xs.MakeRaw]" ]
+    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs.Session).AuthCookie" [ color="saddlebrown" tooltip="at xs.go:651: calling [(blitter.com/go/xs.Session).AuthCookie]\nat xs.go:675: calling [(blitter.com/go/xs.Session).AuthCookie]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.main$3" [ arrowhead="normalnoneodot" tooltip="at xs.go:1075: calling [blitter.com/go/xs/xs.main$3]" ]
+    "blitter.com/go/xs/xs.doCopyMode" -> "blitter.com/go/xs/xs.buildCmdRemoteToLocal" [ tooltip="at xs.go:444: calling [blitter.com/go/xs/xs.buildCmdRemoteToLocal]" ]
+    "blitter.com/go/xs/xs.doCopyMode" -> "(blitter.com/go/xs/xsnet.Conn).Read" [ color="saddlebrown" tooltip="at xs.go:424: calling [(blitter.com/go/xs/xsnet.Conn).Read]" ]
+    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs.Session).Who" [ tooltip="at xs.go:651: calling [(blitter.com/go/xs.Session).Who]\nat xs.go:659: calling [(blitter.com/go/xs.Session).Who]" color="saddlebrown" ]
+    "blitter.com/go/xs/xs.main" -> "(blitter.com/go/xs/xsnet.Conn).Read" [ color="saddlebrown" tooltip="at xs.go:1039: calling [(blitter.com/go/xs/xsnet.Conn).Read]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xsnet.Dial" [ color="saddlebrown" tooltip="at xs.go:960: calling [blitter.com/go/xs/xsnet.Dial]" ]
+    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs.Session).Op" [ color="saddlebrown" tooltip="at xs.go:651: calling [(blitter.com/go/xs.Session).Op]\nat xs.go:655: calling [(blitter.com/go/xs.Session).Op]" ]
+    "blitter.com/go/xs/xs.rejectUserMsg" -> "blitter.com/go/xs/spinsult.GetSentence" [ color="saddlebrown" tooltip="at xs.go:577: calling [blitter.com/go/xs/spinsult.GetSentence]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.launchTuns" [ tooltip="at xs.go:1081: calling [blitter.com/go/xs/xs.launchTuns]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(vendor/golang.org/x/net/idna.labelError).Error" [ style="dashed" color="saddlebrown" tooltip="at xs.go:507: calling [(vendor/golang.org/x/net/idna.labelError).Error]" ]
+    "blitter.com/go/xs/xs.Copy" -> "blitter.com/go/xs/xs.copyBuffer" [ tooltip="at xs.go:116: calling [blitter.com/go/xs/xs.copyBuffer]" ]
+    "blitter.com/go/xs/xs.main" -> "github.com/mattn/go-isatty.IsTerminal" [ color="saddlebrown" tooltip="at xs.go:977: calling [github.com/mattn/go-isatty.IsTerminal]" ]
+    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs.Session).TermType" [ color="saddlebrown" tooltip="at xs.go:651: calling [(blitter.com/go/xs.Session).TermType]\nat xs.go:667: calling [(blitter.com/go/xs.Session).TermType]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/tls.RecordHeaderError).Error" [ style="dashed" color="saddlebrown" tooltip="at xs.go:507: calling [(crypto/tls.RecordHeaderError).Error]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/x509.UnknownAuthorityError).Error" [ style="dashed" color="saddlebrown" tooltip="at xs.go:507: calling [(crypto/x509.UnknownAuthorityError).Error]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.exitWithStatus" [ tooltip="at xs.go:772: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:853: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:963: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:1027: calling [blitter.com/go/xs/xs.exitWithStatus]\nat xs.go:1101: calling [blitter.com/go/xs/xs.exitWithStatus]" ]
+    "blitter.com/go/xs/xs.doShellMode$2" -> "blitter.com/go/xs/xs.doShellMode$2$1" [ tooltip="at xs.go:541: calling [blitter.com/go/xs/xs.doShellMode$2$1]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.doShellMode" [ tooltip="at xs.go:1082: calling [blitter.com/go/xs/xs.doShellMode]" ]
+    "blitter.com/go/xs/xs.doShellMode" -> "blitter.com/go/xs/xs.doShellMode$2" [ arrowhead="normalnoneodot" tooltip="at xs.go:551: calling [blitter.com/go/xs/xs.doShellMode$2]" ]
+    "blitter.com/go/xs/xs.buildCmdLocalToRemote" -> "blitter.com/go/xs.GetTool" [ color="saddlebrown" tooltip="at xs.go:283: calling [blitter.com/go/xs.GetTool]\nat xs.go:311: calling [blitter.com/go/xs.GetTool]\nat xs.go:312: calling [blitter.com/go/xs.GetTool]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(*blitter.com/go/xs/xsnet.Conn).GetStatus" [ color="saddlebrown" tooltip="at xs.go:513: calling [(*blitter.com/go/xs/xsnet.Conn).GetStatus]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/tls.alert).Error" [ style="dashed" color="saddlebrown" tooltip="at xs.go:507: calling [(crypto/tls.alert).Error]" ]
+    "blitter.com/go/xs/xs.doShellMode" -> "blitter.com/go/xs/xs.handleTermResizes" [ tooltip="at xs.go:527: calling [blitter.com/go/xs/xs.handleTermResizes]" ]
+    "blitter.com/go/xs/xs.main" -> "(*blitter.com/go/xs/xsnet.Conn).SetupChaff" [ color="saddlebrown" tooltip="at xs.go:1050: calling [(*blitter.com/go/xs/xsnet.Conn).SetupChaff]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(context.deadlineExceededError).Error" [ style="dashed" color="saddlebrown" tooltip="at xs.go:507: calling [(context.deadlineExceededError).Error]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/aes.KeySizeError).Error" [ style="dashed" color="saddlebrown" tooltip="at xs.go:507: calling [(crypto/aes.KeySizeError).Error]" ]
+    "blitter.com/go/xs/xs.doShellMode$2$1" -> "blitter.com/go/xs/xs.Copy" [ tooltip="at xs.go:539: calling [blitter.com/go/xs/xs.Copy]" ]
+    "blitter.com/go/xs/xs.doCopyMode" -> "(blitter.com/go/xs.Session).Cmd" [ color="saddlebrown" tooltip="at xs.go:356: calling [(blitter.com/go/xs.Session).Cmd]\nat xs.go:441: calling [(blitter.com/go/xs.Session).Cmd]" ]
+    "blitter.com/go/xs/xs.doCopyMode" -> "(*blitter.com/go/xs/xsnet.Conn).WritePacket" [ tooltip="at xs.go:417: calling [(*blitter.com/go/xs/xsnet.Conn).WritePacket]" color="saddlebrown" ]
+    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs.Session).ConnHost" [ color="saddlebrown" tooltip="at xs.go:651: calling [(blitter.com/go/xs.Session).ConnHost]\nat xs.go:663: calling [(blitter.com/go/xs.Session).ConnHost]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.sendSessionParams" [ tooltip="at xs.go:1022: calling [blitter.com/go/xs/xs.sendSessionParams]" ]
+    "blitter.com/go/xs/xs.doCopyMode" -> "blitter.com/go/xs/xs.buildCmdLocalToRemote" [ tooltip="at xs.go:364: calling [blitter.com/go/xs/xs.buildCmdLocalToRemote]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.parseNonSwitchArgs" [ tooltip="at xs.go:796: calling [blitter.com/go/xs/xs.parseNonSwitchArgs]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.restoreTermState" [ tooltip="at xs.go:1024: calling [blitter.com/go/xs/xs.restoreTermState]\nat xs.go:1090: calling [blitter.com/go/xs/xs.restoreTermState]\nat xs.go:1096: calling [blitter.com/go/xs/xs.restoreTermState]" ]
+    "blitter.com/go/xs/xs.main" -> "(*blitter.com/go/xs/xsnet.Conn).DisableChaff" [ color="saddlebrown" tooltip="at xs.go:1055: calling [(*blitter.com/go/xs/xsnet.Conn).DisableChaff]" arrowhead="normalnoneodiamond" ]
+    "blitter.com/go/xs/xs.launchTuns" -> "blitter.com/go/xs/xs.reqTunnel" [ tooltip="at xs.go:645: calling [blitter.com/go/xs/xs.reqTunnel]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/x509.UnhandledCriticalExtension).Error" [ style="dashed" color="saddlebrown" tooltip="at xs.go:507: calling [(crypto/x509.UnhandledCriticalExtension).Error]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(compress/flate.CorruptInputError).Error" [ style="dashed" color="saddlebrown" tooltip="at xs.go:507: calling [(compress/flate.CorruptInputError).Error]" ]
+    "blitter.com/go/xs/xs.buildCmdLocalToRemote" -> "blitter.com/go/xs/xs.getTreeSizeSubCmd" [ tooltip="at xs.go:335: calling [blitter.com/go/xs/xs.getTreeSizeSubCmd]" ]
+    "blitter.com/go/xs/xs.buildCmdRemoteToLocal" -> "blitter.com/go/xs.GetTool" [ color="saddlebrown" tooltip="at xs.go:256: calling [blitter.com/go/xs.GetTool]\nat xs.go:263: calling [blitter.com/go/xs.GetTool]" ]
+    "blitter.com/go/xs/xs.sendSessionParams" -> "(blitter.com/go/xs/xsnet.Conn).Write" [ style="dashed" color="saddlebrown" tooltip="at xs.go:675: calling [(blitter.com/go/xs/xsnet.Conn).Write]\nat xs.go:671: calling [(blitter.com/go/xs/xsnet.Conn).Write]\nat xs.go:667: calling [(blitter.com/go/xs/xsnet.Conn).Write]\nat xs.go:663: calling [(blitter.com/go/xs/xsnet.Conn).Write]\nat xs.go:659: calling [(blitter.com/go/xs/xsnet.Conn).Write]\nat xs.go:655: calling [(blitter.com/go/xs/xsnet.Conn).Write]" ]
+    "blitter.com/go/xs/xs.main" -> "(*blitter.com/go/xs.Session).SetStatus" [ color="saddlebrown" tooltip="at xs.go:1025: calling [(*blitter.com/go/xs.Session).SetStatus]\nat xs.go:1043: calling [(*blitter.com/go/xs.Session).SetStatus]\nat xs.go:1047: calling [(*blitter.com/go/xs.Session).SetStatus]\nat xs.go:1086: calling [(*blitter.com/go/xs.Session).SetStatus]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(*github.com/pkg/errors.fundamental).Error" [ style="dashed" color="saddlebrown" tooltip="at xs.go:507: calling [(*github.com/pkg/errors.fundamental).Error]" ]
+    "blitter.com/go/xs/xs.handleTermResizes" -> "blitter.com/go/xs/xs.handleTermResizes$1" [ arrowhead="normalnoneodot" tooltip="at termsize_unix.go:21: calling [blitter.com/go/xs/xs.handleTermResizes$1]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.usageShell" [ style="dashed" tooltip="at xs.go:852: calling [blitter.com/go/xs/xs.usageShell]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.restoreTermState" [ arrowhead="normalnoneodiamond" tooltip="at xs.go:984: calling [blitter.com/go/xs/xs.restoreTermState]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs.ReadPassword" [ color="saddlebrown" tooltip="at xs.go:1005: calling [blitter.com/go/xs.ReadPassword]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "blitter.com/go/xs/xs.doShellMode$1$1" [ arrowhead="normalnoneodiamond" tooltip="at xs.go:491: calling [blitter.com/go/xs/xs.doShellMode$1$1]" ]
+    "blitter.com/go/xs/xs.handleTermResizes$1" -> "(*blitter.com/go/xs/xsnet.Conn).WritePacket" [ color="saddlebrown" tooltip="at termsize_unix.go:33: calling [(*blitter.com/go/xs/xsnet.Conn).WritePacket]" ]
+    "blitter.com/go/xs/xs.main" -> "(*blitter.com/go/xs/xsnet.Conn).EnableChaff" [ color="saddlebrown" tooltip="at xs.go:1054: calling [(*blitter.com/go/xs/xsnet.Conn).EnableChaff]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(crypto/x509.HostnameError).Error" [ style="dashed" color="saddlebrown" tooltip="at xs.go:507: calling [(crypto/x509.HostnameError).Error]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(*crypto/tls.permanentError).Error" [ color="saddlebrown" tooltip="at xs.go:507: calling [(*crypto/tls.permanentError).Error]" style="dashed" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.doCopyMode" [ tooltip="at xs.go:1085: calling [blitter.com/go/xs/xs.doCopyMode]" ]
+    "blitter.com/go/xs/xs.copyBuffer" -> "blitter.com/go/xs/xs.copyBuffer$2" [ style="dashed" tooltip="at xs.go:186: calling [blitter.com/go/xs/xs.copyBuffer$2]" ]
+    "blitter.com/go/xs/xs.copyBuffer" -> "blitter.com/go/xs/xs.copyBuffer$3" [ style="dashed" tooltip="at xs.go:186: calling [blitter.com/go/xs/xs.copyBuffer$3]" ]
+    "blitter.com/go/xs/xs.main" -> "(*blitter.com/go/xs/xsnet.Conn).Close" [ arrowhead="normalnoneodiamond" color="saddlebrown" tooltip="at xs.go:972: calling [(*blitter.com/go/xs/xsnet.Conn).Close]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.rejectUserMsg" [ tooltip="at xs.go:1046: calling [blitter.com/go/xs/xs.rejectUserMsg]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.usageCp" [ tooltip="at xs.go:852: calling [blitter.com/go/xs/xs.usageCp]" style="dashed" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(vendor/golang.org/x/net/idna.runeError).Error" [ color="saddlebrown" tooltip="at xs.go:507: calling [(vendor/golang.org/x/net/idna.runeError).Error]" style="dashed" ]
+    "blitter.com/go/xs/xs.copyBuffer" -> "(blitter.com/go/xs/xsnet.Conn).Write" [ tooltip="at xs.go:193: calling [(blitter.com/go/xs/xsnet.Conn).Write]" style="dashed" color="saddlebrown" ]
+    "blitter.com/go/xs/xs.copyBuffer" -> "blitter.com/go/xs/xs.copyBuffer$1" [ style="dashed" tooltip="at xs.go:186: calling [blitter.com/go/xs/xs.copyBuffer$1]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.main$1" [ tooltip="at xs.go:790: calling [blitter.com/go/xs/xs.main$1]" arrowhead="normalnoneodot" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xs.localUserName" [ tooltip="at xs.go:803: calling [blitter.com/go/xs/xs.localUserName]" ]
+    "blitter.com/go/xs/xs.reqTunnel" -> "(*blitter.com/go/xs/xsnet.Conn).WritePacket" [ color="saddlebrown" tooltip="at xs.go:594: calling [(*blitter.com/go/xs/xsnet.Conn).WritePacket]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs/xsnet.Init" [ color="saddlebrown" tooltip="at xs.go:865: calling [blitter.com/go/xs/xsnet.Init]" ]
+    "blitter.com/go/xs/xs.main" -> "blitter.com/go/xs.NewSession" [ tooltip="at xs.go:1021: calling [blitter.com/go/xs.NewSession]" color="saddlebrown" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(blitter.com/go/xs.Session).Status" [ tooltip="at xs.go:514: calling [(blitter.com/go/xs.Session).Status]\nat xs.go:519: calling [(blitter.com/go/xs.Session).Status]" color="saddlebrown" ]
+    "blitter.com/go/xs/xs.handleTermResizes$1" -> "blitter.com/go/xs/xs.GetSize" [ tooltip="at termsize_unix.go:27: calling [blitter.com/go/xs/xs.GetSize]" ]
+    "blitter.com/go/xs/xs.reqTunnel" -> "blitter.com/go/xs/logger.LogDebug" [ color="saddlebrown" tooltip="at xs.go:593: calling [blitter.com/go/xs/logger.LogDebug]" ]
+    "blitter.com/go/xs/xs.main$3" -> "(*blitter.com/go/xs/xsnet.Conn).WritePacket" [ tooltip="at xs.go:1072: calling [(*blitter.com/go/xs/xsnet.Conn).WritePacket]" color="saddlebrown" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "blitter.com/go/xs/xs.restoreTermState" [ tooltip="at xs.go:503: calling [blitter.com/go/xs/xs.restoreTermState]\nat xs.go:518: calling [blitter.com/go/xs/xs.restoreTermState]" ]
+    "blitter.com/go/xs/xs.doShellMode$1" -> "(compress/flate.InternalError).Error" [ tooltip="at xs.go:507: calling [(compress/flate.InternalError).Error]" style="dashed" color="saddlebrown" ]
 }
--- a/xs/xs.go
+++ b/xs/xs.go
@ -1,6 +1,6 @@
 // xs client
 //
-// Copyright (c) 2017-2019 Russell Magee
+// Copyright (c) 2017-2020 Russell Magee
 // Licensed under the terms of the MIT license (see LICENSE.mit in this
 // distribution)
 //
@ -14,10 +14,8 @@ import (
 	"flag"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
 	"math/rand"
-	"net"
 	"os"
 	"os/exec"
 	"os/user"
@ -31,7 +29,7 @@ import (
 	"time"

 	"net/http"
-	_ "net/http/pprof"
+	_ "net/http/pprof" //nolint:gosec

 	xs "blitter.com/go/xs"
 	"blitter.com/go/xs/logger"
@ -58,27 +56,39 @@ var (

 ////////////////////////////////////////////////////

+const (
+	CmdExitedEarly               = 2
+	XSNetDialFailed              = 3
+	ErrReadingAuthReply          = 253
+	ServerRejectedSecureProposal = 254
+	GeneralProtocolErr           = 255
+)
+
+const (
+	DeadCharPrefix = 0x1d
+)
+
 // Praise Bob. Do not remove, lest ye lose Slack.
 const bob = string("\r\n\r\n" +
 	"@@@@@@@^^~~~~~~~~~~~~~~~~~~~~^@@@@@@@@@\r\n" +
 	"@@@@@@^     ~^  @  @@ @ @ @ I  ~^@@@@@@\r\n" +
 	"@@@@@            ~ ~~ ~I          @@@@@\r\n" +
-	"@@@@'                  '  _,w@<    @@@@\r\n" +
+	"@@@@'                  '  _,w@<    @@@@    .\r\n" +
 	"@@@@     @@@@@@@@w___,w@@@@@@@@  @  @@@\r\n" +
-	"@@@@     @@@@@@@@@@@@@@@@@@@@@@  I  @@@\r\n" +
+	"@@@@     @@@@@@@@@@@@@@@@@@@@@@  I  @@@   Bob\r\n" +
 	"@@@@     @@@@@@@@@@@@@@@@@@@@*@[ i  @@@\r\n" +
-	"@@@@     @@@@@@@@@@@@@@@@@@@@[][ | ]@@@\r\n" +
+	"@@@@     @@@@@@@@@@@@@@@@@@@@[][ | ]@@@           bOb\r\n" +
 	"@@@@     ~_,,_ ~@@@@@@@~ ____~ @    @@@\r\n" +
-	"@@@@    _~ ,  ,  `@@@~  _  _`@ ]L  J@@@\r\n" +
+	"@@@@    _~ ,  ,  `@@@~  _  _`@ ]L  J@@@    o\r\n" +
 	"@@@@  , @@w@ww+   @@@ww``,,@w@ ][  @@@@\r\n" +
-	"@@@@,  @@@@www@@@ @@@@@@@ww@@@@@[  @@@@\r\n" +
+	"@@@@,  @@@@www@@@ @@@@@@@ww@@@@@[  @@@@      BOB\r\n" +
 	"@@@@@_|| @@@@@@P' @@P@@@@@@@@@@@[|c@@@@\r\n" +
-	"@@@@@@w| '@@P~  P]@@@-~, ~Y@@^'],@@@@@@\r\n" +
+	"@@@@@@w| '@@P~  P]@@@-~, ~Y@@^'],@@@@@@           . o\r\n" +
 	"@@@@@@@[   _        _J@@Tk     ]]@@@@@@\r\n" +
 	"@@@@@@@@,@ @@, c,,,,,,,y ,w@@[ ,@@@@@@@\r\n" +
-	"@@@@@@@@@ i @w   ====--_@@@@@  @@@@@@@@\r\n" +
+	"@@@@@@@@@ i @w   ====--_@@@@@  @@@@@@@@       o .\r\n" +
 	"@@@@@@@@@@`,P~ _ ~^^^^Y@@@@@  @@@@@@@@@\r\n" +
-	"@@@@^^=^@@^   ^' ,ww,w@@@@@ _@@@@@@@@@@\r\n" +
+	"@@@@^^=^@@^   ^' ,ww,w@@@@@ _@@@@@@@@@@    B   o   B\r\n" +
 	"@@@_xJ~ ~   ,    @@@@@@@P~_@@@@@@@@@@@@\r\n" +
 	"@@   @,   ,@@@,_____   _,J@@@@@@@@@@@@@\r\n" +
 	"@@L  `' ,@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@\r\n" +
@ -92,6 +102,14 @@ type (
 	escSeqs map[byte]escHandler
 )

+var (
+	escs = escSeqs{
+		'i': func(io.Writer) { os.Stdout.Write([]byte("\x1b[s\x1b[2;1H\x1b[1;31m[HKEXSH]\x1b[39;49m\x1b[u")) },
+		't': func(io.Writer) { os.Stdout.Write([]byte("\x1b[1;32m[HKEXSH]\x1b[39;49m")) },
+		'B': func(io.Writer) { os.Stdout.Write([]byte("\x1b[1;32m" + bob + "\x1b[39;49m")) },
+	}
+)
+
 // Copy copies from src to dst until either EOF is reached
 // on src or an error occurs. It returns the number of bytes
 // copied and the first error encountered while copying, if any.
@ -139,11 +157,6 @@ func copyBuffer(dst io.Writer, src io.Reader, buf []byte) (written int64, err er
 	// or tunnel traffic indicator - note we cannot just spawn a goroutine
 	// here, as copyBuffer() returns after each burst of data. Scope must
 	// outlive individual copyBuffer calls).
-	escs := escSeqs{
-		'i': func(io.Writer) { os.Stdout.Write([]byte("\x1b[s\x1b[2;1H\x1b[1;31m[HKEXSH]\x1b[39;49m\x1b[u")) },
-		't': func(io.Writer) { os.Stdout.Write([]byte("\x1b[1;32m[HKEXSH]\x1b[39;49m")) },
-		'B': func(io.Writer) { os.Stdout.Write([]byte("\x1b[1;32m" + bob + "\x1b[39;49m")) },
-	}

 	/*
 		// If the reader has a WriteTo method, use it to do the copy.
@ -155,7 +168,7 @@ func copyBuffer(dst io.Writer, src io.Reader, buf []byte) (written int64, err er
 		if rt, ok := dst.(io.ReaderFrom); ok {
 			return rt.ReadFrom(src)
 		}
-	*/
+	*/ //nolint:gocritic,nolintlint
 	if buf == nil {
 		size := 32 * 1024
 		if l, ok := src.(*io.LimitedReader); ok && int64(size) > l.N {
@ -176,8 +189,8 @@ func copyBuffer(dst io.Writer, src io.Reader, buf []byte) (written int64, err er
 			// A repeat of 4 keys (conveniently 'dead' chars for most
 			// interactive shells; here CTRL-]) shall introduce
 			// some special responses or actions on the client side.
-			if seqPos < 4 {
-				if buf[0] == 0x1d {
+			if seqPos < 4 { //nolint:gomnd
+				if buf[0] == DeadCharPrefix {
 					seqPos++
 				}
 			} else {
@ -224,7 +237,7 @@ func GetSize() (cols, rows int, err error) {

 	if err != nil {
 		log.Println(err)
-		cols, rows = 80, 24 //failsafe
+		cols, rows = 80, 24 // failsafe
 	} else {
 		n, err := fmt.Sscanf(string(out), "%d %d\n", &rows, &cols)
 		if n < 2 ||
@ -240,21 +253,47 @@ func GetSize() (cols, rows int, err error) {
 	return
 }

-// doCopyMode begins a secure xs local<->remote file copy operation.
-//
-// TODO: reduce gocyclo
-func doCopyMode(conn *xsnet.Conn, remoteDest bool, files string, rec *xs.Session) (exitStatus uint32, err error) {
-	if remoteDest {
-		log.Println("local files:", files, "remote filepath:", string(rec.Cmd()))
+func buildCmdRemoteToLocal(copyQuiet bool, copyLimitBPS uint, destPath string) (captureStderr bool, cmd string, args []string) {
+	// Detect if we have 'pv'
+	// pipeview http://www.ivarch.com/programs/pv.shtml
+	// and use it for nice client progress display.
+	_, pverr := os.Stat("/usr/bin/pv")
+	if pverr != nil {
+		_, pverr = os.Stat("/usr/local/bin/pv")
+	}

-		var c *exec.Cmd
+	if copyQuiet || pverr != nil {
+		// copyQuiet and copyLimitBPS are not applicable in dumb copy mode
+		captureStderr = true
+		cmd = xs.GetTool("tar")

-		//os.Clearenv()
-		//os.Setenv("HOME", u.HomeDir)
-		//os.Setenv("TERM", "vt102") // TODO: server or client option?
+		args = []string{"-xz", "-C", destPath}
+	} else {
+		// TODO: Query remote side for total file/dir size
+		bandwidthInBytesPerSec := " -L " + fmt.Sprintf("%d ", copyLimitBPS)
+		displayOpts := " -pre " //nolint:goconst
+		cmd = xs.GetTool("bash")
+		args = []string{"-c", "pv " + displayOpts + bandwidthInBytesPerSec + "| tar -xz -C " + destPath}
+	}
+	log.Printf("[%v %v]\n", cmd, args)
+	return
+}

-		cmdName := "/bin/tar"
-		cmdArgs := []string{"-cz", "-f", "/dev/stdout"}
+func buildCmdLocalToRemote(copyQuiet bool, copyLimitBPS uint, files string) (captureStderr bool, cmd string, args []string) {
+	// Detect if we have 'pv'
+	// pipeview http://www.ivarch.com/programs/pv.shtml
+	// and use it for nice client progress display.
+	_, pverr := os.Stat("/usr/bin/pv")
+	if pverr != nil {
+		_, pverr = os.Stat("/usr/local/bin/pv")
+	}
+
+	if pverr != nil {
+		// copyQuiet and copyLimitBPS are not applicable in dumb copy mode
+
+		captureStderr = true
+		cmd = xs.GetTool("tar")
+		args = []string{"-cz", "-f", "/dev/stdout"}
 		files = strings.TrimSpace(files)
 		// Awesome fact: tar actually can take multiple -C args, and
 		// changes to the dest dir *as it sees each one*. This enables
@ -272,22 +311,79 @@ func doCopyMode(conn *xsnet.Conn, remoteDest bool, files string, rec *xs.Session
 			v, _ = filepath.Abs(v) // #nosec
 			dirTmp, fileTmp := path.Split(v)
 			if dirTmp == "" {
-				cmdArgs = append(cmdArgs, fileTmp)
+				args = append(args, fileTmp)
 			} else {
-				cmdArgs = append(cmdArgs, "-C", dirTmp, fileTmp)
+				args = append(args, "-C", dirTmp, fileTmp)
 			}
 		}
+	} else {
+		captureStderr = copyQuiet
+		bandwidthInBytesPerSec := " -L " + fmt.Sprintf("%d", copyLimitBPS)
+		displayOpts := " -pre " //nolint:goconst,nolintlint
+		cmd = xs.GetTool("bash")
+		args = []string{"-c", xs.GetTool("tar") + " -cz -f /dev/stdout "}
+		files = strings.TrimSpace(files)
+		// Awesome fact: tar actually can take multiple -C args, and
+		// changes to the dest dir *as it sees each one*. This enables
+		// its use below, where clients can send scattered sets of source
+		// files and dirs to be extracted to a single dest dir server-side,
+		// whilst preserving the subtrees of dirs on the other side.
+		// Eg., tar -c -f /dev/stdout -C /dirA fileInA -C /some/where/dirB fileInB /foo/dirC
+		// packages fileInA, fileInB, and dirC at a single toplevel in the tar.
+		// The tar authors are/were real smarties :)
+		//
+		// This is the 'scatter/gather' logic to allow specification of
+		// files and dirs in different trees to be deposited in a single
+		// remote destDir.
+		for _, v := range strings.Split(files, " ") {
+			v, _ = filepath.Abs(v) // #nosec
+			dirTmp, fileTmp := path.Split(v)
+			if dirTmp == "" {
+				args[1] = args[1] + fileTmp + " "
+			} else {
+				args[1] = args[1] + " -C " + dirTmp + " " + fileTmp + " "
+			}
+		}
+		args[1] = args[1] + "| pv" + displayOpts + bandwidthInBytesPerSec + " -s " + getTreeSizeSubCmd(files) + " -c"
+	}

-		log.Printf("[%v %v]\n", cmdName, cmdArgs)
-		// NOTE the lack of quotes around --xform option's sed expression.
-		// When args are passed in exec() format, no quoting is required
-		// (as this isn't input from a shell) (right? -rlm 20180823)
+	log.Printf("[%v %v]\n", cmd, args)
+	return
+}
+
+func getTreeSizeSubCmd(paths string) (c string) {
+	if runtime.GOOS == "linux" {
+		c = " $(du -cb " + paths + " | tail -1 | cut -f 1) "
+	} else {
+		c = " $(expr $(du -c " + paths + ` | tail -1 | cut -f 1) \* 1024) `
+	}
+	return c
+}
+
+// doCopyMode begins a secure xs local<->remote file copy operation.
+//
+// TODO: reduce gocyclo
+func doCopyMode(conn *xsnet.Conn, remoteDest bool, files string, copyQuiet bool, copyLimitBPS uint, rec *xs.Session) (exitStatus uint32, err error) {
+	if remoteDest {
+		log.Println("local files:", files, "remote filepath:", string(rec.Cmd()))
+
+		var c *exec.Cmd
+
+		// os.Clearenv()
+		// os.Setenv("HOME", u.HomeDir)
+		// os.Setenv("TERM", "vt102") // TODO: server or client option?
+
+		captureStderr, cmdName, cmdArgs := buildCmdLocalToRemote(copyQuiet, copyLimitBPS, strings.TrimSpace(files))
 		c = exec.Command(cmdName, cmdArgs...) // #nosec
 		c.Dir, _ = os.Getwd()                 // #nosec
 		log.Println("[wd:", c.Dir, "]")
 		c.Stdout = conn
 		stdErrBuffer := new(bytes.Buffer)
-		c.Stderr = stdErrBuffer
+		if captureStderr {
+			c.Stderr = stdErrBuffer
+		} else {
+			c.Stderr = os.Stderr
+		}

 		// Start the command (no pty)
 		err = c.Start() // returns immediately
@ -308,7 +404,7 @@ func doCopyMode(conn *xsnet.Conn, remoteDest bool, files string, rec *xs.Session
 		if err != nil {
 			fmt.Println("cmd exited immediately. Cannot get cmd.Wait().ExitStatus()")
 			err = errors.New("cmd exited prematurely")
-			exitStatus = uint32(2)
+			exitStatus = uint32(CmdExitedEarly)
 		} else {
 			if err = c.Wait(); err != nil {
 				if exiterr, ok := err.(*exec.ExitError); ok {
@ -320,13 +416,15 @@ func doCopyMode(conn *xsnet.Conn, remoteDest bool, files string, rec *xs.Session
 					// an ExitStatus() method with the same signature.
 					if status, ok := exiterr.Sys().(syscall.WaitStatus); ok {
 						exitStatus = uint32(status.ExitStatus())
-						fmt.Print(stdErrBuffer)
+						if captureStderr {
+							fmt.Print(stdErrBuffer)
+						}
 					}
 				}
 			}
 			// send CSOExitStatus to inform remote (server) end cp is done
 			log.Println("Sending local exitStatus:", exitStatus)
-			r := make([]byte, 4)
+			r := make([]byte, 4) //nolint:gomnd
 			binary.BigEndian.PutUint32(r, exitStatus)
 			_, we := conn.WritePacket(r, xsnet.CSOExitStatus)
 			if we != nil {
@ -334,7 +432,7 @@ func doCopyMode(conn *xsnet.Conn, remoteDest bool, files string, rec *xs.Session
 			}

 			// Do a final read for remote's exit status
-			s := make([]byte, 4)
+			s := make([]byte, 4) //nolint:gomnd
 			_, remErr := conn.Read(s)
 			if remErr != io.EOF &&
 				!strings.Contains(remErr.Error(), "use of closed network") &&
@ -353,18 +451,11 @@ func doCopyMode(conn *xsnet.Conn, remoteDest bool, files string, rec *xs.Session
 		}
 	} else {
 		log.Println("remote filepath:", string(rec.Cmd()), "local files:", files)
-		var c *exec.Cmd
-
-		cmdName := "/bin/tar"
 		destPath := files

-		cmdArgs := []string{"-xz", "-C", destPath}
-		log.Printf("[%v %v]\n", cmdName, cmdArgs)
-		// NOTE the lack of quotes around --xform option's sed expression.
-		// When args are passed in exec() format, no quoting is required
-		// (as this isn't input from a shell) (right? -rlm 20180823)
-		//cmdArgs := []string{"-xvz", "-C", destPath, `--xform=s#.*/\(.*\)#\1#`}
-		c = exec.Command(cmdName, cmdArgs...) // #nosec
+		_, cmdName, cmdArgs := buildCmdRemoteToLocal(copyQuiet, copyLimitBPS, destPath)
+
+		c := exec.Command(cmdName, cmdArgs...) // #nosec
 		c.Stdin = conn
 		c.Stdout = os.Stdout
 		c.Stderr = os.Stderr
@ -401,8 +492,8 @@ func doCopyMode(conn *xsnet.Conn, remoteDest bool, files string, rec *xs.Session
 // doShellMode begins an xs shell session (one-shot command or
 // interactive).
 func doShellMode(isInteractive bool, conn *xsnet.Conn, oldState *xs.State, rec *xs.Session) {
-	//client reader (from server) goroutine
-	//Read remote end's stdout
+	// Client reader (from server) goroutine
+	// Read remote end's stdout

 	wg.Add(1)
 	// #gv:s/label=\"doShellMode\$1\"/label=\"shellRemoteToStdin\"/
@ -420,7 +511,7 @@ func doShellMode(isInteractive bool, conn *xsnet.Conn, oldState *xs.State, rec *
 		// exit with inerr == nil
 		_, inerr := io.Copy(os.Stdout, conn)
 		if inerr != nil {
-			_ = xs.Restore(int(os.Stdin.Fd()), oldState) // #nosec
+			restoreTermState(oldState)
 			// Copy operations and user logging off will cause
 			// a "use of closed network connection" so handle that
 			// gracefully here
@ -435,7 +526,7 @@ func doShellMode(isInteractive bool, conn *xsnet.Conn, oldState *xs.State, rec *

 		if isInteractive {
 			log.Println("[* Got EOF *]")
-			_ = xs.Restore(int(os.Stdin.Fd()), oldState) // #nosec
+			restoreTermState(oldState)
 			exitWithStatus(int(rec.Status()))
 		}
 	}
@ -456,6 +547,8 @@ func doShellMode(isInteractive bool, conn *xsnet.Conn, oldState *xs.State, rec *
 			_, outerr := func(conn *xsnet.Conn, r io.Reader) (w int64, e error) {
 				// Copy() expects EOF so this will
 				// exit with outerr == nil
+				// NOTE we use a local implementation of Copy() to allow
+				// for custom key sequences to trigger local actions
 				w, e = Copy(conn, r)
 				return w, e
 			}(conn, os.Stdin)
@ -463,7 +556,7 @@ func doShellMode(isInteractive bool, conn *xsnet.Conn, oldState *xs.State, rec *
 			if outerr != nil {
 				log.Println(outerr)
 				fmt.Println(outerr)
-				_ = xs.Restore(int(os.Stdin.Fd()), oldState) // #nosec
+				restoreTermState(oldState)
 				log.Println("[Hanging up]")
 				exitWithStatus(0)
 			}
@ -477,15 +570,15 @@ func doShellMode(isInteractive bool, conn *xsnet.Conn, oldState *xs.State, rec *
 }

 func usageShell() {
-	fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0])            // nolint: errcheck
-	fmt.Fprintf(os.Stderr, "%s [opts] [user]@server\n", os.Args[0]) // nolint: errcheck
+	fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "%s [opts] [user]@server\n", os.Args[0])
 	flag.PrintDefaults()
 }

 func usageCp() {
-	fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0])                                         // nolint: errcheck
-	fmt.Fprintf(os.Stderr, "%s [opts] srcFileOrDir [...] [user]@server[:dstpath]\n", os.Args[0]) // nolint: errcheck
-	fmt.Fprintf(os.Stderr, "%s [opts] [user]@server[:srcFileOrDir] dstPath\n", os.Args[0])       // nolint: errcheck
+	fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "%s [opts] srcFileOrDir [...] [user]@server[:dstpath]\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "%s [opts] [user]@server[:srcFileOrDir] dstPath\n", os.Args[0])
 	flag.PrintDefaults()
 }

@ -501,18 +594,18 @@ func rejectUserMsg() string {
 //
 // Server responds with [CSOTunAck:rport] or [CSOTunRefused:rport]
 // (handled in xsnet.Read())
-func reqTunnel(hc *xsnet.Conn, lp uint16, p string /*net.Addr*/, rp uint16) {
+func reqTunnel(hc *xsnet.Conn, lp uint16 /*, p string*/ /*net.Addr*/, rp uint16) {
 	// Write request to server so it can attempt to set up its end
 	var bTmp bytes.Buffer
 	if e := binary.Write(&bTmp, binary.BigEndian, lp); e != nil {
-		fmt.Fprintln(os.Stderr, "reqTunnel:", e) // nolint: errcheck
+		fmt.Fprintln(os.Stderr, "reqTunnel:", e)
 	}
 	if e := binary.Write(&bTmp, binary.BigEndian, rp); e != nil {
-		fmt.Fprintln(os.Stderr, "reqTunnel:", e) // nolint: errcheck
+		fmt.Fprintln(os.Stderr, "reqTunnel:", e)
 	}
-	_ = logger.LogDebug(fmt.Sprintln("[Client sending CSOTunSetup]")) // nolint: gosec
+	_ = logger.LogDebug(fmt.Sprintln("[Client sending CSOTunSetup]"))
 	if n, e := hc.WritePacket(bTmp.Bytes(), xsnet.CSOTunSetup); e != nil || n != len(bTmp.Bytes()) {
-		fmt.Fprintln(os.Stderr, "reqTunnel:", e) // nolint: errcheck
+		fmt.Fprintln(os.Stderr, "reqTunnel:", e)
 	}
 }

@ -525,7 +618,7 @@ func parseNonSwitchArgs(a []string) (user, host, path string, isDest bool, other
 		if strings.Contains(arg, ":") || strings.Contains(arg, "@") {
 			fancyArg := strings.Split(flag.Arg(i), "@")
 			var fancyHostPath []string
-			if len(fancyArg) < 2 {
+			if len(fancyArg) < 2 { //nolint:gomnd
 				//TODO: no user specified, use current
 				fancyUser = "[default:getUser]"
 				fancyHostPath = strings.Split(fancyArg[0], ":")
@ -551,8 +644,8 @@ func parseNonSwitchArgs(a []string) (user, host, path string, isDest bool, other
 	return fancyUser, fancyHost, fancyPath, isDest, otherArgs
 }

-func launchTuns(conn *xsnet.Conn, remoteHost string, tuns string) {
-	remAddrs, _ := net.LookupHost(remoteHost) // nolint: gosec
+func launchTuns(conn *xsnet.Conn /*remoteHost string,*/, tuns string) {
+	/*remAddrs, _ := net.LookupHost(remoteHost)*/ //nolint:gocritic,nolintlint

 	if tuns == "" {
 		return
@ -561,8 +654,8 @@ func launchTuns(conn *xsnet.Conn, remoteHost string, tuns string) {
 	tunSpecs := strings.Split(tuns, ",")
 	for _, tunItem := range tunSpecs {
 		var lPort, rPort uint16
-		_, _ = fmt.Sscanf(tunItem, "%d:%d", &lPort, &rPort) // nolint: gosec
-		reqTunnel(conn, lPort, remAddrs[0], rPort)
+		_, _ = fmt.Sscanf(tunItem, "%d:%d", &lPort, &rPort)
+		reqTunnel(conn, lPort /*remAddrs[0],*/, rPort)
 	}
 }

@ -597,50 +690,86 @@ func sendSessionParams(conn io.Writer /* *xsnet.Conn*/, rec *xs.Session) (e erro
 }

 // TODO: reduce gocyclo
-func main() {
-	var vopt bool
-	var gopt bool //login via password, asking server to generate authToken
-	var dbg bool
-	var shellMode bool   // if true act as shell, else file copier
-	var cipherAlg string //cipher alg
-	var hmacAlg string   //hmac alg
-	var kexAlg string    //KEX/KEM alg
-	var server string
-	var port uint
-	var cmdStr string
-	var tunSpecStr string // lport1:rport1[,lport2:rport2,...]
+func main() { //nolint: funlen, gocyclo
+	var (
+		isInteractive  bool
+		vopt           bool
+		gopt           bool // true: login via password, asking server to generate authToken
+		dbg            bool
+		shellMode      bool // true: act as shell, false: file copier
+		cipherAlg      string
+		hmacAlg        string
+		kexAlg         string
+		server         string
+		port           uint
+		cmdStr         string
+		tunSpecStr     string // lport1:rport1[,lport2:rport2,...]
+		rekeySecs      uint
+		remodRequested bool // true: when rekeying, switch to random cipher/hmac alg
+		copySrc        []byte
+		copyDst        string
+		copyQuiet      bool
+		copyLimitBPS   uint

-	var copySrc []byte
-	var copyDst string
+		authCookie    string
+		chaffEnabled  bool
+		chaffFreqMin  uint
+		chaffFreqMax  uint
+		chaffBytesMax uint

-	var authCookie string
-	var chaffEnabled bool
-	var chaffFreqMin uint
-	var chaffFreqMax uint
-	var chaffBytesMax uint
+		op []byte
+	)

-	var op []byte
-	isInteractive := false
+	// === Common (xs and xc) option parsing

 	flag.BoolVar(&vopt, "v", false, "show version")
 	flag.BoolVar(&dbg, "d", false, "debug logging")
-	flag.StringVar(&cipherAlg, "c", "C_AES_256", "session `cipher` [C_AES_256 | C_TWOFISH_128 | C_BLOWFISH_64 | C_CRYPTMT1]")
-	flag.StringVar(&hmacAlg, "m", "H_SHA256", "session `HMAC` [H_SHA256 | H_SHA512]")
-	flag.StringVar(&kexAlg, "k", "KEX_HERRADURA512", "KEx `alg` [KEX_HERRADURA{256/512/1024/2048} | KEX_KYBER{512/768/1024} | KEX_NEWHOPE | KEX_NEWHOPE_SIMPLE]")
-	flag.StringVar(&kcpMode, "K", "unused", "KCP `alg`, one of [KCP_NONE | KCP_AES | KCP_BLOWFISH | KCP_CAST5 | KCP_SM4 | KCP_SALSA20 | KCP_SIMPLEXOR | KCP_TEA | KCP_3DES | KCP_TWOFISH | KCP_XTEA] to use KCP (github.com/xtaci/kcp-go) reliable UDP instead of TCP")
-	flag.UintVar(&port, "p", 2000, "``port")
-	//flag.StringVar(&authCookie, "a", "", "auth cookie")
+	flag.StringVar(&cipherAlg, "c", "C_AES_256", "session `cipher`"+`
+      C_AES_256
+      C_TWOFISH_128
+      C_BLOWFISH_64
+      C_CRYPTMT1
+      C_HOPSCOTCH
+      C_CHACHA20_12`)
+	flag.StringVar(&hmacAlg, "m", "H_SHA256", "session `HMAC`"+`
+      H_SHA256
+      H_SHA512
+      H_WHIRLPOOL`)
+	flag.StringVar(&kexAlg, "k", "KEX_HERRADURA512", "KEx `alg`"+`
+      KEX_HERRADURA256
+      KEX_HERRADURA512
+      KEX_HERRADURA1024
+      KEX_HERRADURA2048
+      KEX_KYBER512
+      KEX_KYBER768
+      KEX_KYBER1024
+      KEX_NEWHOPE
+      KEX_NEWHOPE_SIMPLE
+      KEX_FRODOKEM_1344AES
+      KEX_FRODOKEM_1344SHAKE
+      KEX_FRODOKEM_976AES
+      KEX_FRODOKEM_976SHAKE`)
+	flag.StringVar(&kcpMode, "K", "unused", "KCP `alg`, one of [KCP_NONE | KCP_AES | KCP_BLOWFISH | KCP_CAST5 | KCP_SM4 | KCP_SALSA20 | KCP_SIMPLEXOR | KCP_TEA | KCP_3DES | KCP_TWOFISH | KCP_XTEA] to use KCP (github.com/xtaci/kcp-go) reliable UDP instead of TCP") //nolint:lll
+	flag.UintVar(&port, "p", 2000, "``port")                                                                                                                                                                                                                            //nolint:gomnd,lll
+	flag.UintVar(&rekeySecs, "r", 300, "rekey interval in `secs`")
+	flag.BoolVar(&remodRequested, "R", false, "Borg Countermeasures (remodulate cipher/hmac alg on each rekey)")
+	//nolint:gocritic,nolintlint // flag.StringVar(&authCookie, "a", "", "auth cookie")
 	flag.BoolVar(&chaffEnabled, "e", true, "enable chaff pkts")
-	flag.UintVar(&chaffFreqMin, "f", 100, "chaff pkt freq min `msecs`")
-	flag.UintVar(&chaffFreqMax, "F", 5000, "chaff pkt freq max `msecs`")
-	flag.UintVar(&chaffBytesMax, "B", 64, "chaff pkt size max `bytes`")
+	flag.UintVar(&chaffFreqMin, "f", 100, "chaff pkt freq min `msecs`")  //nolint:gomnd
+	flag.UintVar(&chaffFreqMax, "F", 5000, "chaff pkt freq max `msecs`") //nolint:gomnd
+	flag.UintVar(&chaffBytesMax, "B", 64, "chaff pkt size max `bytes`")  //nolint:gomnd

 	flag.StringVar(&cpuprofile, "cpuprofile", "", "write cpu profile to <`file`>")
 	flag.StringVar(&memprofile, "memprofile", "", "write memory profile to <`file`>")

+	// === xc vs. xs option parsing
+
 	// Find out what program we are (shell or copier)
 	myPath := strings.Split(os.Args[0], string(os.PathSeparator))
-	if myPath[len(myPath)-1] != "xc" && myPath[len(myPath)-1] != "xc.exe" {
+	if myPath[len(myPath)-1] != "xc" &&
+		myPath[len(myPath)-1] != "_xc" &&
+		myPath[len(myPath)-1] != "xc.exe" &&
+		myPath[len(myPath)-1] != "_xc.exe" {
 		// xs accepts a command (-x) but not
 		// a srcpath (-r) or dstpath (-t)
 		flag.StringVar(&cmdStr, "x", "", "run <`command`> (if not specified, run interactive shell)")
@ -649,10 +778,19 @@ func main() {
 		shellMode = true
 		flag.Usage = usageShell
 	} else {
+		flag.BoolVar(&copyQuiet, "q", false, "do not output progress bar during copy")
+		flag.UintVar(&copyLimitBPS, "L", 8589934592, "copy max rate in bytes per sec") //nolint:gomnd
 		flag.Usage = usageCp
 	}
 	flag.Parse()

+	if vopt {
+		fmt.Printf("version %s (%s)\n", version, gitCommit)
+		exitWithStatus(0)
+	}
+
+	// === Profiling instrumentation
+
 	if cpuprofile != "" {
 		f, err := os.Create(cpuprofile)
 		if err != nil {
@ -661,23 +799,25 @@ func main() {
 		defer f.Close()
 		fmt.Println("StartCPUProfile()")
 		if err := pprof.StartCPUProfile(f); err != nil {
-			log.Fatal("could not start CPU profile: ", err)
+			log.Fatal("could not start CPU profile: ", err) //nolint:gocritic
 		} else {
 			defer pprof.StopCPUProfile()
 		}

-		go func() { http.ListenAndServe("localhost:6060", nil) }()
+		go func() { http.ListenAndServe("localhost:6060", nil) }() //nolint:errcheck,gosec
 	}

+	// === User, host, port and path args for file operations, if applicable
+
 	remoteUser, remoteHost, tmpPath, pathIsDest, otherArgs :=
 		parseNonSwitchArgs(flag.Args())
-	//fmt.Println("otherArgs:", otherArgs)
+	//nolint:gocritic,nolintlint // fmt.Println("otherArgs:", otherArgs)

 	// Set defaults if user doesn't specify user, path or port
 	var uname string
 	if remoteUser == "" {
-		u, _ := user.Current() // nolint: gosec
-		uname = u.Username
+		u, _ := user.Current()
+		uname = localUserName(u)
 	} else {
 		uname = remoteUser
 	}
@ -689,6 +829,8 @@ func main() {
 		tmpPath = "."
 	}

+	// === Copy mode arg and copy src/dest setup
+
 	var fileArgs string
 	if !shellMode /*&& tmpPath != ""*/ {
 		// -if pathIsSrc && len(otherArgs) > 1 ERROR
@ -720,59 +862,60 @@ func main() {
 		}
 	}

-	// Do some more option consistency checks
+	// === Do some final option consistency checks

-	//fmt.Println("server finally is:", server)
+	//nolint:gocritic,nolintlint // fmt.Println("server finally is:", server)
 	if flag.NFlag() == 0 && server == "" {
 		flag.Usage()
 		exitWithStatus(0)
 	}

-	if vopt {
-		fmt.Printf("version %s (%s)\n", version, gitCommit)
-		exitWithStatus(0)
-	}
-
-	if len(cmdStr) != 0 && (len(copySrc) != 0 || len(copyDst) != 0) {
+	if cmdStr != "" && (len(copySrc) != 0 || copyDst != "") {
 		log.Fatal("incompatible options -- either cmd (-x) or copy ops but not both")
 	}

-	//-------------------------------------------------------------------
 	// Here we have parsed all options and can now carry out
 	// either the shell session or copy operation.
 	_ = shellMode

-	Log, _ = logger.New(logger.LOG_USER|logger.LOG_DEBUG|logger.LOG_NOTICE|logger.LOG_ERR, "xs") // nolint: errcheck,gosec
+	Log, _ = logger.New(logger.LOG_USER|logger.LOG_DEBUG|logger.LOG_NOTICE|logger.LOG_ERR, "xs")
 	xsnet.Init(dbg, "xs", logger.LOG_USER|logger.LOG_DEBUG|logger.LOG_NOTICE|logger.LOG_ERR)
 	if dbg {
 		log.SetOutput(Log)
 	} else {
-		log.SetOutput(ioutil.Discard)
+		log.SetOutput(io.Discard)
 	}

+	// === Auth token fetch for login
+
 	if !gopt {
 		// See if we can log in via an auth token
-		u, _ := user.Current() // nolint: gosec
-		ab, aerr := ioutil.ReadFile(fmt.Sprintf("%s/.xs_id", u.HomeDir))
+		u, _ := user.Current()
+		ab, aerr := os.ReadFile(fmt.Sprintf("%s/%s", u.HomeDir, xsnet.XS_ID_AUTHTOKFILE))
 		if aerr == nil {
-			idx := strings.Index(string(ab), remoteHost)
-			if idx >= 0 {
-				ab = ab[idx:]
-				entries := strings.SplitN(string(ab), "\n", -1)
-				authCookie = strings.TrimSpace(entries[0])
-				// Security scrub
-				ab = nil
-				runtime.GC()
-			} else {
+			for _, line := range strings.Split(string(ab), "\n") {
+				line += "\n"
+				idx := strings.Index(line, remoteHost+":"+uname)
+				if idx >= 0 {
+					line = line[idx:]
+					entries := strings.SplitN(line, "\n", -1)
+					authCookie = strings.TrimSpace(entries[0])
+					// Security scrub
+					line = ""
+					break
+				}
+			}
+			if authCookie == "" {
 				_, _ = fmt.Fprintln(os.Stderr, "[no authtoken, use -g to request one from server]")
 			}
 		} else {
-			log.Printf("[cannot read %s/.xs_id]\n", u.HomeDir)
+			log.Printf("[cannot read %s/%s]\n", u.HomeDir, xsnet.XS_ID_AUTHTOKFILE)
 		}
 	}
+	runtime.GC()

-	// Enforce some sane min/max vals on chaff flags
-	if chaffFreqMin < 2 {
+	// === Enforce some sane min/max vals on chaff flags
+	if chaffFreqMin < 2 { //nolint:gomnd
 		chaffFreqMin = 2
 	}
 	if chaffFreqMax == 0 {
@ -782,15 +925,17 @@ func main() {
 		chaffBytesMax = 64
 	}

+	// === Shell vs. Copy mode chaff and cmd setup
+
 	if shellMode {
 		// We must make the decision about interactivity before Dial()
 		// as it affects chaffing behaviour. 20180805
 		if gopt {
-			fmt.Fprintln(os.Stderr, "[requesting authtoken from server]") // nolint: errcheck
+			fmt.Fprintln(os.Stderr, "[requesting authtoken from server]")
 			op = []byte{'A'}
 			chaffFreqMin = 2
 			chaffFreqMax = 10
-		} else if len(cmdStr) == 0 {
+		} else if cmdStr == "" {
 			op = []byte{'s'}
 			isInteractive = true
 		} else {
@ -811,138 +956,200 @@ func main() {
 			// client->server file copy
 			// src file list is in copySrc
 			op = []byte{'D'}
-			//fmt.Println("client->server copy:", string(copySrc), "->", copyDst)
+			//nolint:gocritic,nolintlint // fmt.Println("client->server copy:", string(copySrc), "->", copyDst)
 			cmdStr = copyDst
 		} else {
 			// server->client file copy
 			// remote src file(s) in copyDsr
 			op = []byte{'S'}
-			//fmt.Println("server->client copy:", string(copySrc), "->", copyDst)
+			//nolint:gocritic,nolintlint // fmt.Println("server->client copy:", string(copySrc), "->", copyDst)
 			cmdStr = string(copySrc)
 		}
 	}

+	// === TCP / KCP Dial setup
+
 	proto := "tcp"
 	if kcpMode != "unused" {
 		proto = "kcp"
 	}
-	conn, err := xsnet.Dial(proto, server, cipherAlg, hmacAlg, kexAlg, kcpMode)
+
+	remodExtArg := ""
+	if remodRequested {
+		remodExtArg = "OPT_REMOD"
+	}
+	// Pass opt to Dial() via extensions arg
+	conn, err := xsnet.Dial(proto, server, cipherAlg, hmacAlg, kexAlg, kcpMode, remodExtArg)
 	if err != nil {
 		fmt.Println(err)
-		exitWithStatus(3)
+		exitWithStatus(XSNetDialFailed)
 	}

+	conn.RekeyHelper(rekeySecs)
+	defer conn.ShutdownRekey()
+
+	// === Shell terminal mode (Shell vs. Copy) setup
+
 	// Set stdin in raw mode if it's an interactive session
 	// TODO: send flag to server side indicating this
 	//  affects shell command used
 	var oldState *xs.State
-	defer conn.Close() // nolint: errcheck
+	defer conn.Close()

-	// From this point on, conn is a secure encrypted channel
+	// === From this point on, conn is a secure encrypted channel

 	if shellMode {
 		if isatty.IsTerminal(os.Stdin.Fd()) {
-			oldState, err = xs.MakeRaw(int(os.Stdin.Fd()))
+			oldState, err = xs.MakeRaw(os.Stdin.Fd())
 			if err != nil {
 				panic(err)
 			}
 			// #gv:s/label=\"main\$1\"/label=\"deferRestore\"/
 			// TODO:.gv:main:1:deferRestore
-			defer func() { _ = xs.Restore(int(os.Stdin.Fd()), oldState) }() // nolint: errcheck,gosec
+			defer restoreTermState(oldState)
 		} else {
 			log.Println("NOT A TTY")
 		}
 	}

-	if len(authCookie) == 0 {
-		//No auth token, prompt for password
-		fmt.Printf("Gimme cookie:")
-		ab, e := xs.ReadPassword(int(os.Stdin.Fd()))
-		fmt.Printf("\r\n")
+	// === Login phase
+
+	// Start login timeout here and disconnect if user/pass phase stalls
+	// iloginImpatience := time.AfterFunc(20*time.Second, func() {
+	// i	fmt.Printf(" .. [you still there? Waiting for a password.]")
+	// i})
+	loginTimeout := time.AfterFunc(30*time.Second, func() { //nolint:gomnd
+		restoreTermState(oldState)
+		fmt.Printf(" .. [login timeout]\n")
+		exitWithStatus(xsnet.CSELoginTimeout)
+	})
+
+	if authCookie == "" {
+		if !gopt {
+			// No auth token, prompt for password
+			fmt.Printf("Gimme cookie:")
+		}
+		ab, e := xs.ReadPassword(os.Stdin.Fd())
+		if !gopt {
+			fmt.Printf("\r\n")
+		}
 		if e != nil {
 			panic(e)
 		}
 		authCookie = string(ab)
 	}
+
+	//nolint:gocritic,nolintlint // i_ = loginImpatience.Stop()
+	_ = loginTimeout.Stop()
 	// Security scrub
 	runtime.GC()

+	// === Session param and TERM setup
+
 	// Set up session params and send over to server
 	rec := xs.NewSession(op, []byte(uname), []byte(remoteHost), []byte(os.Getenv("TERM")), []byte(cmdStr), []byte(authCookie), 0)
 	sendErr := sendSessionParams(&conn, rec)
 	if sendErr != nil {
-		_ = xs.Restore(int(os.Stdin.Fd()), oldState) // nolint: errcheck,gosec
-		rec.SetStatus(254)
-		fmt.Fprintln(os.Stderr, "Error: server rejected secure proposal params") // nolint: errcheck
+		restoreTermState(oldState)
+		rec.SetStatus(ServerRejectedSecureProposal)
+		fmt.Fprintln(os.Stderr, "Error: server rejected secure proposal params or login timed out")
 		exitWithStatus(int(rec.Status()))
-		//log.Fatal(sendErr)
+		//nolint:gocritic,nolintlint // log.Fatal(sendErr)
 	}

-	//Security scrub
-	authCookie = "" // nolint: ineffassign
+	// Security scrub
+	authCookie = "" //nolint: ineffassign
 	runtime.GC()

-	// Read auth reply from server
+	// === Login Auth
+
+	// === Read auth reply from server
 	authReply := make([]byte, 1) // bool: 0 = fail, 1 = pass
 	_, err = conn.Read(authReply)
 	if err != nil {
-		fmt.Fprintln(os.Stderr, "Error reading auth reply") // nolint: errcheck
-		rec.SetStatus(255)
+		// === Exit if auth reply not received
+		fmt.Fprintln(os.Stderr, "Error reading auth reply")
+		rec.SetStatus(ErrReadingAuthReply)
 	} else if authReply[0] == 0 {
-		fmt.Fprintln(os.Stderr, rejectUserMsg()) // nolint: errcheck
-		rec.SetStatus(255)
+		// === .. or if auth failed
+		fmt.Fprintln(os.Stderr, rejectUserMsg())
+		rec.SetStatus(GeneralProtocolErr)
 	} else {
-		// Set up chaffing to server
+		// === Set up connection keepalive to server
+		conn.StartupKeepAlive() // goroutine, returns immediately
+		defer conn.ShutdownKeepAlive()
+
+		// === Set up chaffing to server
 		conn.SetupChaff(chaffFreqMin, chaffFreqMax, chaffBytesMax) // enable client->server chaffing
 		if chaffEnabled {
 			// #gv:s/label=\"main\$2\"/label=\"deferCloseChaff\"/
 			// TODO:.gv:main:2:deferCloseChaff
-			conn.EnableChaff() // goroutine, returns immediately
-			defer conn.DisableChaff()
+			conn.StartupChaff() // goroutine, returns immediately
 			defer conn.ShutdownChaff()
 		}

-		// Keepalive for any tunnels that may exist
+		// === (goroutine) Start keepAliveWorker for tunnels
 		// #gv:s/label=\"main\$1\"/label=\"tunKeepAlive\"/
 		// TODO:.gv:main:1:tunKeepAlive
-		//[1]: better to always send tunnel keepAlives even if client didn't specify
-		//     any, to prevent listeners from knowing this.
-		//[1] if tunSpecStr != "" {
+		// [1]: better to always send tunnel keepAlives even if client didn't specify
+		//      any, to prevent listeners from knowing this.
+		// [1] if tunSpecStr != "" {
 		keepAliveWorker := func() {
 			for {
 				// Add a bit of jitter to keepAlive so it doesn't stand out quite as much
-				time.Sleep(time.Duration(2000-rand.Intn(200)) * time.Millisecond)
+				time.Sleep(time.Duration(2000-rand.Intn(200)) * time.Millisecond) //nolint:gosec,gomnd
 				// FIXME: keepAlives should probably have small random packet len/data as well
 				// to further obscure them vs. interactive or tunnel data
 				// keepAlives must be  >=2 bytes, due to processing elsewhere
-				conn.WritePacket([]byte{0, 0}, xsnet.CSOTunKeepAlive) // nolint: errcheck,gosec
+				conn.WritePacket([]byte{0, 0}, xsnet.CSOTunKeepAlive) //nolint: errcheck
 			}
 		}
 		go keepAliveWorker()
-		//[1]}
+		// [1]}

+		// === Session entry (shellMode or copyMode)
 		if shellMode {
-			launchTuns(&conn, remoteHost, tunSpecStr)
+			// === (shell) launch tunnels
+			launchTuns(&conn /*remoteHost,*/, tunSpecStr)
 			doShellMode(isInteractive, &conn, oldState, rec)
-		} else { // copyMode
-			s, _ := doCopyMode(&conn, pathIsDest, fileArgs, rec) // nolint: errcheck,gosec
+		} else {
+			// === (.. or file copy)
+			s, _ := doCopyMode(&conn, pathIsDest, fileArgs, copyQuiet, copyLimitBPS, rec)
 			rec.SetStatus(s)
 		}

 		if rec.Status() != 0 {
-			_ = xs.Restore(int(os.Stdin.Fd()), oldState)                         // nolint: errcheck,gosec
-			fmt.Fprintln(os.Stderr, "Session exited with status:", rec.Status()) // nolint: errcheck
+			restoreTermState(oldState)
+			fmt.Fprintln(os.Stderr, "Session exited with status:", rec.Status())
 		}
 	}

 	if oldState != nil {
-		_ = xs.Restore(int(os.Stdin.Fd()), oldState) // nolint: gosec
+		restoreTermState(oldState)
 		oldState = nil
 	}

+	// === Exit
 	exitWithStatus(int(rec.Status()))
 }

+// currentUser returns the current username minus any OS-specific prefixes
+// such as MS Windows workgroup prefixes (eg. workgroup\user).
+func localUserName(u *user.User) string {
+	if u == nil {
+		log.Fatal("null User?!")
+	}
+
+	// WinAPI: username may have CIFS prefix %USERDOMAIN%\
+	userspec := strings.Split(u.Username, `\`)
+	username := userspec[len(userspec)-1]
+	return username
+}
+
+func restoreTermState(oldState *xs.State) {
+	_ = xs.Restore(os.Stdin.Fd(), oldState)
+}
+
 // exitWithStatus wraps os.Exit() plus does any required pprof housekeeping
 func exitWithStatus(status int) {
 	if cpuprofile != "" {
@ -957,9 +1164,8 @@ func exitWithStatus(status int) {
 		defer f.Close()
 		runtime.GC() // get up-to-date statistics
 		if err := pprof.WriteHeapProfile(f); err != nil {
-			log.Fatal("could not write memory profile: ", err)
+			log.Fatal("could not write memory profile: ", err) //nolint:gocritic
 		}
 	}
-
 	os.Exit(status)
 }
--- a/xsd.initrc
+++ b/xsd.initrc
@ -6,7 +6,9 @@ XSD_USER=root
 XSD_HOME=/var/run
 INST_PREFIX=/usr/local
 COMMAND=$INST_PREFIX/sbin/xsd
-ARGS=""
+#ARGS="-L -aK KEX_all -aC C_all -aH H_all"
+echo "SET ARGS in this script to define allow KEX, cipher and hmac algs"
+exit 1

 depend() {
    need net
@ -28,7 +30,7 @@ start() {
        -d ${XSD_HOME} \
        --make-pidfile --pidfile ${XSD_PIDFILE} \
        --start --quiet --background \
-        --exec "${COMMAND}" "${ARGS}"
+        --exec "${COMMAND}" -- ${ARGS}
    eend $?
 }

--- a/xsd.sysvrc
+++ b/xsd.sysvrc
@ -0,0 +1,166 @@
+#! /bin/sh
+
+### BEGIN INIT INFO
+# Provides:		xsd
+# Required-Start:	$remote_fs $syslog
+# Required-Stop:	$remote_fs $syslog
+# Default-Start:	2 3 4 5
+# Default-Stop:		
+# Short-Description:	eXperimental Shell Daemon
+### END INIT INFO
+
+set -e
+
+echo "SET XSD_OPTS in this script to define allow KEX, cipher and hmac algs"
+#XSD_OPTS="-L -aK KEX_all -aC C_all -aH H_all"
+exit 1
+
+# /etc/init.d/xsd: start and stop the eXperimental "secure" Shell Daemon
+
+test -x /usr/local/sbin/xsd || exit 0
+( /usr/local/sbin/xsd -h 2>&1 | grep -q chaff ) 2>/dev/null || exit 0
+
+umask 022
+
+#if test -f /etc/default/ssh; then
+#    . /etc/default/ssh
+#fi
+
+. /lib/lsb/init-functions
+
+if [ -n "$2" ]; then
+    XSD_OPTS="$XSD_OPTS $2"
+fi
+
+# Are we running from init?
+run_by_init() {
+    ([ "$previous" ] && [ "$runlevel" ]) || [ "$runlevel" = S ]
+}
+
+check_for_no_start() {
+    # forget it if we're trying to start, and /etc/xsd_not_to_be_run exists
+    if [ -e /etc/xsd_not_to_be_run ]; then 
+	if [ "$1" = log_end_msg ]; then
+	    log_end_msg 0 || true
+	fi
+	if ! run_by_init; then
+	    log_action_msg "eXperimental Shell Daemon not in use (/etc/xsd_not_to_be_run)" || true
+	fi
+	exit 0
+    fi
+}
+
+check_dev_null() {
+    if [ ! -c /dev/null ]; then
+	if [ "$1" = log_end_msg ]; then
+	    log_end_msg 1 || true
+	fi
+	if ! run_by_init; then
+	    log_action_msg "/dev/null is not a character device!" || true
+	fi
+	exit 1
+    fi
+}
+
+#check_privsep_dir() {
+#    # Create the PrivSep empty dir if necessary
+#    if [ ! -d /run/sshd ]; then
+#	mkdir /run/sshd
+#	chmod 0755 /run/sshd
+#    fi
+#}
+
+#check_config() {
+#    if [ ! -e /etc/xsd_not_to_be_run ]; then
+#	/usr/local/sbin/xsd $XSD_OPTS -t || exit 1
+#    fi
+#}
+
+export PATH="${PATH:+$PATH:}/usr/local/sbin:/usr/sbin:/sbin"
+
+case "$1" in
+  start)
+	#check_privsep_dir
+	check_for_no_start
+	check_dev_null
+	log_daemon_msg "Starting eXperimental Shell Daemon" "xsd" || true
+	if start-stop-daemon --start -b --quiet --oknodo --chuid 0:0 --exec /usr/local/sbin/xsd -- $XSD_OPTS; then
+	    log_end_msg 0 || true
+	else
+	    log_end_msg 1 || true
+	fi
+	;;
+  stop)
+	log_daemon_msg "Stopping eXperimental Shell Daemon" "xsd" || true
+	if start-stop-daemon --stop --quiet --oknodo --exec /usr/local/sbin/xsd; then
+	    log_end_msg 0 || true
+	else
+	    log_end_msg 1 || true
+	fi
+	;;
+
+  reload|force-reload)
+	check_for_no_start
+	#check_config
+	log_daemon_msg "Reloading eXperimental Shell Daemon's configuration" "xsd" || true
+	if start-stop-daemon --stop --signal 1 --quiet --oknodo --exec /usr/local/sbin/xsd; then
+	    log_end_msg 0 || true
+	else
+	    log_end_msg 1 || true
+	fi
+	;;
+
+  restart)
+	#check_privsep_dir
+	#check_config
+	log_daemon_msg "Restarting eXperimental Shell Daemon" "xsd" || true
+	start-stop-daemon --stop --quiet --oknodo --retry 30 --exec /usr/local/sbin/xsd
+	check_for_no_start log_end_msg
+	check_dev_null log_end_msg
+	if start-stop-daemon --start -b --quiet --oknodo --chuid 0:0 --exec /usr/local/sbin/xsd -- $XSD_OPTS; then
+	    log_end_msg 0 || true
+	else
+	    log_end_msg 1 || true
+	fi
+	;;
+
+  try-restart)
+	#check_privsep_dir
+	#check_config
+	log_daemon_msg "Restarting eXperimental Shell Daemon" "xsd" || true
+	RET=0
+	start-stop-daemon --stop --quiet --retry 30 --exec /usr/local/sbin/xsd || RET="$?"
+	case $RET in
+	    0)
+		# old daemon stopped
+		check_for_no_start log_end_msg
+		check_dev_null log_end_msg
+		if start-stop-daemon --start -b --quiet --oknodo --chuid 0:0 --exec /usr/local/sbin/xsd -- $XSD_OPTS; then
+		    log_end_msg 0 || true
+		else
+		    log_end_msg 1 || true
+		fi
+		;;
+	    1)
+		# daemon not running
+		log_progress_msg "(not running)" || true
+		log_end_msg 0 || true
+		;;
+	    *)
+		# failed to stop
+		log_progress_msg "(failed to stop)" || true
+		log_end_msg 1 || true
+		;;
+	esac
+	;;
+
+  status)
+	status_of_proc -p /run/xsd.pid /usr/local/sbin/xsd xsd && exit 0 || exit $?
+	;;
+
+  *)
+	log_action_msg "Usage: /etc/init.d/xsd {start|stop|reload|force-reload|restart|try-restart|status}" || true
+	exit 1
+esac
+
+exit 0
--- a/xsd/Makefile
+++ b/xsd/Makefile
@ -1,10 +1,16 @@
 .PHONY: clean all vis lint

+ifeq ($(GARBLE),y)
+GO = garble -literals -tiny -debugdir=garbled
+else
+GO = go
+endif
+
 EXTPKGS = binary,bytes,crypto,encoding,errors,flag,fmt,internal,io,log,net,os,path,runtime,time,strings,sync,syscall
 EXE = $(notdir $(shell pwd))

 all:
-	go build $(BUILDOPTS) .
+	$(GO) build $(BUILDOPTS) .

 clean:
 	$(RM) $(EXE) $(EXE).exe
@ -14,5 +20,5 @@ vis:
 	../fixup-gv.sh xsd.go && cat xsd-vis.gv | dot -Tpng -oxsd-vis-fixedup.png

 lint:
-	-gometalinter --deadline=60s | sort
+	-golangci-lint run

--- a/xsd/xsd-vis-fixedup.png
+++ b/xsd/xsd-vis-fixedup.png
--- a/xsd/xsd-vis.gv
+++ b/xsd/xsd-vis.gv
--- a/xsd/xsd.go
+++ b/xsd/xsd.go
--- a/xsnet/Makefile
+++ b/xsnet/Makefile
@ -1,12 +1,18 @@
 .PHONY: info clean lib

+ifeq ($(GARBLE),y)
+GO = garble -tiny -literals -debugdir=garbled
+else
+GO = go
+endif
+
 all: lib

 clean:
 	go clean .

 lib: info
-	go install .
+	$(GO) install .

 ifneq ($(MSYSTEM),)
 info:
--- a/xsnet/chan.go
+++ b/xsnet/chan.go
@ -1,6 +1,6 @@
 package xsnet

-// Copyright (c) 2017-2019 Russell Magee
+// Copyright (c) 2017-2020 Russell Magee
 // Licensed under the terms of the MIT license (see LICENSE.mit in this
 // distribution)
 //
@ -21,10 +21,12 @@ import (
 	"log"

 	"blitter.com/go/cryptmt"
-	"blitter.com/go/wanderer"
+	"blitter.com/go/hopscotch"
+	"blitter.com/go/xs/logger"
+	"github.com/aead/chacha20/chacha"
 	"golang.org/x/crypto/blowfish"
 	"golang.org/x/crypto/twofish"
-
+	whirlpool "github.com/jzelinskie/whirlpool"
 	// hash algos must be manually imported thusly:
 	// (Would be nice if the golang pkg docs were more clear
 	// on this...)
@ -56,10 +58,20 @@ func expandKeyMat(keymat []byte, blocksize int) []byte {
 	return keymat
 }

-/* Support functionality to set up encryption after a channel has
-been negotiated via xsnet.go
-*/
-func (hc Conn) getStream(keymat []byte) (rc cipher.Stream, mc hash.Hash, err error) {
+// Choose a cipher and hmac alg from supported sets, given two uint8 values
+func getNewStreamAlgs(cb uint8, hb uint8) (config uint32) {
+	// Get new cipher and hash algs (clamped to valid values) based on
+	// the input rekeying data
+	c := (cb % CAlgNoneDisallowed)
+	h := (hb % HmacNoneDisallowed)
+	config = uint32(h<<8) | uint32(c)
+	logger.LogDebug(fmt.Sprintf("[Chose new algs [%d:%d]", h, c))
+	return
+}
+
+// (Re-)initialize the keystream and hmac state for an xsnet.Conn, returning
+// a cipherStream and hash
+func (hc *Conn) getStream(keymat []byte) (rc cipher.Stream, mc hash.Hash, err error) {
 	var key []byte
 	var block cipher.Block
 	var iv []byte
@ -103,11 +115,25 @@ func (hc Conn) getStream(keymat []byte) (rc cipher.Stream, mc hash.Hash, err err
 		rc = cipher.NewOFB(block, iv)
 		log.Printf("[cipher BLOWFISH_64 (%d)]\n", copts)
 	case CAlgCryptMT1:
-		rc = cryptmt.NewCipher(keymat)
+		rc = cryptmt.New(nil, nil, keymat)
+		//NOTE: this alg is not based on block cipher, no IV
 		log.Printf("[cipher CRYPTMT1 (%d)]\n", copts)
-	case CAlgWanderer:
-		rc = wanderer.NewCodec(nil, nil, keymat, 3, 3)
-		log.Printf("[cipher WANDERER (%d)]\n", copts)
+	case CAlgHopscotch:
+		rc = hopscotch.New(nil, nil, 4, keymat)
+		//NOTE: this alg is not based on block cipher, no IV
+		log.Printf("[cipher HOPSCOTCH (%d)]\n", copts)
+	case CAlgChaCha20_12:
+		keymat = expandKeyMat(keymat, chacha.KeySize)
+		key = keymat[0:chacha.KeySize]
+		ivlen = chacha.INonceSize
+		iv = keymat[chacha.KeySize : chacha.KeySize+ivlen]
+		rc, err = chacha.NewCipher(iv, key, chacha.INonceSize)
+		if err != nil {
+			log.Printf("[ChaCha20 config error]\n")
+			fmt.Printf("[ChaCha20 config error]\n")
+		}
+		// TODO: SetCounter() to something derived from key or nonce or extra keymat?
+		log.Printf("[cipher CHACHA20_12 (%d)]\n", copts)
 	default:
 		log.Printf("[invalid cipher (%d)]\n", copts)
 		fmt.Printf("DOOFUS SET A VALID CIPHER ALG (%d)\n", copts)
@ -131,6 +157,9 @@ func (hc Conn) getStream(keymat []byte) (rc cipher.Stream, mc hash.Hash, err err
 		if !halg.Available() {
 			log.Fatal("hash not available!")
 		}
+	case HmacWHIRLPOOL:
+		log.Printf("[hash HmacWHIRLPOOL (%d)]\n", hopts)
+		mc = whirlpool.New()
 	default:
 		log.Printf("[invalid hmac (%d)]\n", hopts)
 		fmt.Printf("DOOFUS SET A VALID HMAC ALG (%d)\n", hopts)
@ -139,7 +168,7 @@ func (hc Conn) getStream(keymat []byte) (rc cipher.Stream, mc hash.Hash, err err
 		//os.Exit(1)
 	}

-	if err != nil {
+	if err == nil && ivlen > 0 {
 		// Feed the IV into the hmac: all traffic in the connection must
 		// feed its data into the hmac afterwards, so both ends can xor
 		// that with the stream to detect corruption.
--- a/xsnet/consts.go
+++ b/xsnet/consts.go
@ -1,6 +1,6 @@
 // consts.go - consts for xsnet

-// Copyright (c) 2017-2019 Russell Magee
+// Copyright (c) 2017-2020 Russell Magee
 // Licensed under the terms of the MIT license (see LICENSE.mit in this
 // distribution)
 //
@ -29,6 +29,10 @@ const (
 	KEX_NEWHOPE_SIMPLE // 'NewHopeLP-Simple' - https://eprint.iacr.org/2016/1157
 	KEX_resvd14
 	KEX_resvd15
+	KEX_FRODOKEM_1344AES
+	KEX_FRODOKEM_1344SHAKE
+	KEX_FRODOKEM_976AES
+	KEX_FRODOKEM_976SHAKE
 	KEX_invalid = 255
 )

@ -48,6 +52,8 @@ const (
 	CSEKEXAlgDenied    // server rejected proposed KEX alg
 	CSECipherAlgDenied // server rejected proposed Cipher alg
 	CSEHMACAlgDenied   // server rejected proposed HMAC alg
+	CSEConnDead        // connection keepalives expired
+	CSELoginTimeout
 )

 // Extended (>255 UNIX exit status) codes
@ -71,6 +77,8 @@ const (
 	CSOTunKeepAlive // client tunnel heartbeat
 	CSOTunDisconn   // server -> client: tunnel rport disconnected
 	CSOTunHangup    // client -> server: tunnel lport hung up
+	CSOKeepAlive    // bidir keepalive packet to monitor main connection
+	CSORekey        // TODO: rekey/re-select session cipher/hash algs
 )

 // TunEndpoint.tunCtl control values - used to control workers for client
@ -90,8 +98,8 @@ const (
 // Channel status Op byte type (see CSONone, ... and CSENone, ...)
 type CSOType uint32

-//TODO: this should be small (max unfragmented packet size?)
-const MAX_PAYLOAD_LEN = 4*1024*1024*1024 - 1
+// TODO: this should be small (max unfragmented packet size?)
+const MAX_PAYLOAD_LEN = 2*1024*1024*1024 - 1

 // Session symmetric crypto algs
 const (
@ -99,7 +107,8 @@ const (
 	CAlgTwofish128 // golang.org/x/crypto/twofish
 	CAlgBlowfish64 // golang.org/x/crypto/blowfish
 	CAlgCryptMT1   //cryptmt using mtwist64
-	CAlgWanderer   // inhouse experimental crypto alg
+	CAlgChaCha20_12
+	CAlgHopscotch
 	CAlgNoneDisallowed
 )

@ -110,8 +119,27 @@ type CSCipherAlg uint32
 const (
 	HmacSHA256 = iota
 	HmacSHA512
+	HmacWHIRLPOOL
 	HmacNoneDisallowed
 )

+// Conn opts outside of basic kex/cipher/hmac connect config
+const (
+	CONone              = iota
+	CORemodulateShields // if set, rekeying also reselects random cipher/hmac alg
+)
+
+type COValue uint32
+
 // Available HMACs for hkex.Conn
 type CSHmacAlg uint32
+
+// Some bounds-checking consts
+const (
+	REKEY_SECS_MIN       = 1
+	REKEY_SECS_MAX       = 28800  // 8 hours
+	CHAFF_FREQ_MSECS_MIN = 1
+	CHAFF_FREQ_MSECS_MAX = 300000 // 5 minutes
+)
+
+const XS_ID_AUTHTOKFILE = ".config/xs/.xs_id"
--- a/xsnet/kcp.go
+++ b/xsnet/kcp.go
@ -40,7 +40,7 @@ func getKCPalgnum(extensions []string) (k KCPAlg) {
 		switch s {
 		case "KCP_NONE":
 			k = KCP_NONE
-			break //out of for
+			break //golint:ignore SA4011 out of for
 		case "KCP_AES":
 			k = KCP_AES
 			break //out of for
--- a/xsnet/net.go
+++ b/xsnet/net.go
--- a/xsnet/tun.go
+++ b/xsnet/tun.go
@ -1,6 +1,6 @@
 // hkextun.go - Tunnel setup using an established xsnet.Conn

-// Copyright (c) 2017-2019 Russell Magee
+// Copyright (c) 2017-2020 Russell Magee
 // Licensed under the terms of the MIT license (see LICENSE.mit in this
 // distribution)
 //
@ -37,6 +37,8 @@ type (
 	// client starts worker to receive/send data using lport
 	// ... client disconnects: sends remhost [CSOTunClose:rport]
 	// ... or server disconnects: sends client [CSOTunClose:lport]
+	// ... or server disconnects: due to client failing to send TunKeepAlive
+	//      events for too long
 	//     server at any time sends [CSOTunRefused:rport] if daemon died
 	// --

--- a/xspasswd/Makefile
+++ b/xspasswd/Makefile
@ -1,10 +1,16 @@
 .PHONY: clean all vis lint

+ifeq ($(GARBLE),y)
+GO = garble -tiny -literals -debugdir=garbled
+else
+GO = go
+endif
+
 EXTPKGS = bytes,errors,flag,fmt,internal,io,log,net,os,path,runtime,time,strings,sync,syscall,binary,encoding
 EXE = $(notdir $(shell pwd))

 all:
-	go build $(BUILDOPTS) .
+	$(GO) build $(BUILDOPTS) .

 clean:
 	$(RM) $(EXE) $(EXE).exe
@ -13,4 +19,4 @@ vis:
 	go-callvis -format png -file xspasswd-vis -ignore $(EXTPKGS) -group pkg,type .

 lint:
-	-gometalinter --deadline=60s | sort
+	-golangci-lint run
--- a/xspasswd/xspasswd.go
+++ b/xspasswd/xspasswd.go
@ -1,7 +1,7 @@
 // Util to generate/store passwords for users in a file akin to /etc/passwd
-// suitable for the demo hkexsh server, using bcrypt.
+// suitable for the xs server, using bcrypt.
 //
-// Copyright (c) 2017-2019 Russell Magee
+// Copyright (c) 2017-2020 Russell Magee
 // Licensed under the terms of the MIT license (see LICENSE.mit in this
 // distribution)
 //
@ -59,7 +59,7 @@ func main() {
 	uname = userName

 	fmt.Printf("New Password:")
-	ab, err := xs.ReadPassword(int(os.Stdin.Fd()))
+	ab, err := xs.ReadPassword(os.Stdin.Fd())
 	fmt.Printf("\r\n")
 	if err != nil {
 		log.Fatal(err)
@ -68,7 +68,7 @@ func main() {
 	newpw = string(ab)

 	fmt.Printf("Confirm:")
-	ab, err = xs.ReadPassword(int(os.Stdin.Fd()))
+	ab, err = xs.ReadPassword(os.Stdin.Fd())
 	fmt.Printf("\r\n")
 	if err != nil {
 		log.Fatal(err)