HMAC portion made into symbolic const

This commit is contained in:
Russ Magee 2018-10-14 00:20:30 -07:00
parent 5d9a110d57
commit a060ae39b1

View file

@ -50,7 +50,8 @@ import (
)
/*---------------------------------------------------------------------*/
const PAD_SZ = 32
const PAD_SZ = 32 // max size of padding applied to each packet
const HMAC_CHK_SZ = 4 // leading bytes of HMAC to xmit for verification
type (
WinSize struct {
@ -145,31 +146,24 @@ func getkexalgnum(extensions ...string) (k KEXAlg) {
for _, s := range extensions {
switch s {
case "KEX_HERRADURA256":
log.Println("[extension arg = KEX_HERRADURA256]")
k = KEX_HERRADURA256
break //out of for
case "KEX_HERRADURA512":
log.Println("[extension arg = KEX_HERRADURA512]")
k = KEX_HERRADURA512
break //out of for
case "KEX_HERRADURA1024":
log.Println("[extension arg = KEX_HERRADURA1024]")
k = KEX_HERRADURA1024
break //out of for
case "KEX_HERRADURA2048":
log.Println("[extension arg = KEX_HERRADURA2048]")
k = KEX_HERRADURA2048
break //out of for
case "KEX_KYBER512":
log.Println("[extension arg = KEX_KYBER512]")
k = KEX_KYBER512
break //out of for
case "KEX_KYBER768":
log.Println("[extension arg = KEX_KYBER768]")
k = KEX_KYBER768
break //out of for
case "KEX_KYBER1024":
log.Println("[extension arg = KEX_KYBER1024]")
k = KEX_KYBER1024
break //out of for
}
@ -208,6 +202,7 @@ func _new(kexAlg KEXAlg, conn *net.Conn) (hc *Conn, e error) {
case KEX_KYBER1024:
log.Printf("[KEx alg %d accepted]\n", kexAlg)
default:
// UNREACHABLE: _getkexalgnum() guarantees a valid KEX value
hc.kex = KEX_HERRADURA256
log.Printf("[KEx alg %d ?? defaults to %d]\n", kexAlg, hc.kex)
}
@ -665,7 +660,7 @@ func (hc Conn) Read(b []byte) (n int, err error) {
}
var ctrlStatOp uint8
var hmacIn [4]uint8
var hmacIn [HMAC_CHK_SZ]uint8
var payloadLen uint32
// Read ctrl/status opcode (CSOHmacInvalid on hmac mismatch)
@ -766,7 +761,7 @@ func (hc Conn) Read(b []byte) (n int, err error) {
//log.Printf("hc.dBuf: %s\n", hex.Dump(hc.dBuf.Bytes()))
}
hTmp := hc.rm.Sum(nil)[0:4]
hTmp := hc.rm.Sum(nil)[0:HMAC_CHK_SZ]
log.Printf("<%04x) HMAC:(i)%s (c)%02x\r\n", decryptN, hex.EncodeToString([]byte(hmacIn[0:])), hTmp)
if *hc.closeStat == CSETruncCSO {
@ -849,7 +844,7 @@ func (hc *Conn) WritePacket(b []byte, op byte) (n int, err error) {
// Calculate hmac on payload
hc.wm.Write(b[0:payloadLen])
hmacOut = hc.wm.Sum(nil)[0:4]
hmacOut = hc.wm.Sum(nil)[0:HMAC_CHK_SZ]
log.Printf(" (%04x> HMAC(o):%s\r\n", payloadLen, hex.EncodeToString(hmacOut))