Merge pull request #34 from Kait0/DNSRes

Added DNS Resolution feature to the client.

CONTRIBUTORS.txt

@@ -5,6 +5,7 @@ to the LiteSpeed Client Library:
     - Brian Prodoehl -- Docker file
     - Amol Desphande -- Windows support
     - Alexis La Goutte -- Travis-CI integration
+    - Bernhard Jaeger -- DNS Resolution
     
 Thank you!
 

EXAMPLES.txt

@@ -9,24 +9,25 @@ Usage Examples
 
 Fetch Google's home page:
 
-    ./http_client -H www.google.com -s 74.125.22.106:443 -p /
-
-    or even
-
-    ./http_client -H www.google.co.uk -s 2a00:1450:4009:80c::2003:443 -p /
+    ./http_client -H www.google.com -s 443 -p /
 
 In the example above, -H specifies the domain; it is also used as the value
 of SNI paramater in the handshake.
 
-The IP address and the port number are specified using the -s flag.
+The port number is specified using the -s flag.
+The ip adress is determined automatically.
+The -6 flag tells the program to use IPv6 instead of IPv4. 
+Note that -6 must be used before -s in order to work.
 
-(Since www.google.com has different IP addresses in different regions, check
-that you are using the correct IP address by resolving www.google.com first
-by using nslookup, dig, ping, or some other tool.)
+You can also specify a certain ip-address with the -s command.
+Note that this example won't work everywhere since google has a lot of different ips. 
+You have to look up the correct one for yourself.
+
+    ./http_client -H www.google.com -s 172.217.22.4:443 -p /
 
 POST a file to calculate its CRC32 checksum:
 
-    ./http_client -H www.litespeedtech.com -s 127.0.0.1:443 \
+    ./http_client -H www.litespeedtech.com -s 443 \
                         -p /cgi-bin/crc32.cgi -P file-256M -M POST
 
     HTTP/1.1 200 OK
@@ -50,7 +51,7 @@ On the command line, I do
 
 To submit several requests concurrently, one can use -n and -r options:
 
-    ./http_client -H www.litespeedtech.com -s 127.0.0.1:443 \
+    ./http_client -H www.litespeedtech.com -s 443 \
                 -p /cgi-bin/crc32.cgi -P file-256M -M POST -n 3 -r 10
 
 This will open three parallel connections which will make ten POST

test/http_client.c

@@ -2,7 +2,6 @@
 /*
  * http_client.c -- A simple HTTP/QUIC client
  */
-
 #ifndef WIN32
 #include <arpa/inet.h>
 #include <netinet/in.h>
@@ -159,7 +158,6 @@ struct lsquic_stream_ctx {
     struct lsquic_reader reader;
 };
 
-
 static lsquic_stream_ctx_t *
 http_client_on_new_stream (void *stream_if_ctx, lsquic_stream_t *stream)
 {
@@ -409,6 +407,7 @@ usage (const char *prog)
 "Usage: %s [opts]\n"
 "\n"
 "Options:\n"
+"				-6 MUST be entered before -s in order to work."
 "   -p PATH     Path to request.  May be specified more than once.\n"
 "   -n CONNS    Number of concurrent connections.  Defaults to 1.\n"
 "   -r NREQS    Total number of requests to send.  Defaults to 1.\n"
@@ -421,6 +420,8 @@ usage (const char *prog)
 "                 content-length\n"
 "   -K          Discard server response\n"
 "   -I          Abort on incomplete reponse from server\n"
+"	-6 IPv6	    The client will try to connect via IPv6\n"
+"				  if this flag is used. If not it will use IPv4.\n"
             , prog);
 }
 
@@ -435,6 +436,8 @@ main (int argc, char **argv)
     struct sport_head sports;
     struct prog prog;
 
+    ipv6 = 0;
+
     TAILQ_INIT(&sports);
     memset(&client_ctx, 0, sizeof(client_ctx));
     client_ctx.hcc_concurrency = 1;
@@ -453,9 +456,12 @@ main (int argc, char **argv)
 
     prog_init(&prog, LSENG_HTTP, &sports, &http_client_if, &client_ctx);
 
-    while (-1 != (opt = getopt(argc, argv, PROG_OPTS "r:R:IKu:EP:M:n:H:p:h")))
+    while (-1 != (opt = getopt(argc, argv, PROG_OPTS "6r:R:IKu:EP:M:n:H:p:h")))
     {
         switch (opt) {
+        case '6':
+            ipv6 = 1;
+            break;
         case 'I':
             client_ctx.hcc_flags |= HCC_ABORT_ON_INCOMPLETE;
             break;

test/prog.c

@@ -1,6 +1,7 @@
 /* Copyright (c) 2017 - 2018 LiteSpeed Technologies Inc.  See LICENSE. */
 #include <assert.h>
 #ifndef WIN32
+#include <arpa/inet.h>
 #include <netinet/in.h>
 #include <signal.h>
 #endif
@@ -82,12 +83,12 @@ void
 prog_print_common_options (const struct prog *prog, FILE *out)
 {
     fprintf(out,
-"   -s SVCPORT  Service port.  Takes on the form of IPv4:port or\n"
-"                 IPv6:port.  For example:\n"
-"                   127.0.0.1:12345\n"
-"                   ::1:12345\n"
-"                 If no -s option is given, 0.0.0.0:12345 address\n"
+"   -s SVCPORT  The port on which the client should connect.\n"
+"                 If no -s option is given, port 443\n"
 "                 is used.\n"
+"                 You can also specify an certain ipadress to be used here.\n"
+"                 To do that enter an ipadress and the port seperated by :\n"
+"                 e.g -s ::1:12345 or -s 0.0.0.0:12345 or -s 443 or -s example.com:443\n"
 #if LSQUIC_DONTFRAG_SUPPORTED
 "   -D          Set `do not fragment' flag on outgoing UDP packets\n"
 #endif
@@ -175,6 +176,7 @@ prog_set_opt (struct prog *prog, int opt, const char *arg)
     case 'o':
         return set_engine_option(&prog->prog_settings,
                                             &prog->prog_version_cleared, arg);
+    
     case 's':
         if (0 == (prog->prog_engine_flags & LSENG_SERVER) &&
                                             !TAILQ_EMPTY(prog->prog_sports))
@@ -371,7 +373,7 @@ prog_prep (struct prog *prog)
 
     if (TAILQ_EMPTY(prog->prog_sports))
     {
-        s = prog_add_sport(prog, "0.0.0.0:12345");
+        s = prog_add_sport(prog, "443");
         if (0 != s)
             return -1;
     }

test/prog.h

@@ -6,6 +6,8 @@
 #ifndef PROG_H
 #define PROG_H 1
 
+int ipv6;	/*True = Program uses ipv6, False = Program uses ipv4*/
+
 struct event;
 struct event_base;
 struct lsquic_hash;

test/test_common.c

@@ -146,6 +146,45 @@ static void getExtensionPtrs()
 
 #endif
 
+int get_Ip_from_DNS(const char* hostname, struct service_port * sport, const char* port, int version)
+{
+    struct sockaddr_in  *const sa4 = (void *)&sport->sas;
+    struct sockaddr_in6 *const sa6 = (void *)&sport->sas;
+    struct addrinfo hints, *servinfo;
+    int rv;
+    char ip[INET6_ADDRSTRLEN];
+
+    memset(&hints, 0, sizeof(hints));
+    if (version)
+        hints.ai_family = AF_INET6;
+    else
+        hints.ai_family = AF_INET;
+    hints.ai_socktype = SOCK_STREAM;
+
+    if ((rv = getaddrinfo(hostname, port, &hints, &servinfo)) != 0){
+        LSQ_ERROR("getaddrinfo: %s\n", gai_strerror(rv));
+        freeaddrinfo(servinfo);
+        return 1;
+    }
+
+    if (version){ /*Ipv6*/
+        memset(sa6, 0, sizeof(*sa6));
+        sa6->sin6_addr = ((struct sockaddr_in6*) servinfo->ai_addr)->sin6_addr;
+        sa6->sin6_family = AF_INET6;
+        sa6->sin6_port = htons(atoi(port));
+        inet_ntop(AF_INET6, &sa6->sin6_addr, ip, INET6_ADDRSTRLEN);
+    }
+    else{/*Ipv4*/
+        sa4->sin_addr = ((struct sockaddr_in *) servinfo->ai_addr)->sin_addr;
+        sa4->sin_family = AF_INET;
+        sa4->sin_port = htons(atoi(port));
+        inet_ntop(AF_INET, &sa4->sin_addr, ip, INET6_ADDRSTRLEN);
+    }
+    memcpy(sport->host, ip, sizeof(ip));
+
+    freeaddrinfo(servinfo);
+    return 0;
+}
 
 static struct packets_in *
 allocate_packets_in (SOCKET_TYPE fd)
@@ -225,38 +264,51 @@ sport_new (const char *optarg, struct prog *prog)
     if (if_name)
     {
         strncpy(sport->if_name, if_name + 1, sizeof(sport->if_name) - 1);
-        sport->if_name[ sizeof(sport->if_name) - 1 ] = '\0';
+        sport->if_name[sizeof(sport->if_name) - 1] = '\0';
         *if_name = '\0';
     }
     else
         sport->if_name[0] = '\0';
 #endif
+
     char *port = strrchr(addr, ':');
-    if (!port)
+    if (!port){/*IpAdress wasn't specified by the user*/
+        if (get_Ip_from_DNS(prog->prog_hostname, sport, addr, ipv6) == 1)
             goto err;
+    }
+    else {
         *port = '\0';
         ++port;
-    if ((uintptr_t) port - (uintptr_t) addr > sizeof(sport->host))
-        goto err;
-    memcpy(sport->host, addr, port - addr);
         
-    struct sockaddr_in  *const sa4 = (void *) &sport->sas;
-    struct sockaddr_in6 *const sa6 = (void *) &sport->sas;
-    if        (inet_pton(AF_INET,  addr, &sa4->sin_addr)) {
+        struct sockaddr_in  *const sa4 = (void *)&sport->sas;
+        struct sockaddr_in6 *const sa6 = (void *)&sport->sas;
+        
+        if (inet_pton(AF_INET, addr, &sa4->sin_addr)){
             sa4->sin_family = AF_INET;
             sa4->sin_port = htons(atoi(port));
-    } else if (memset(sa6, 0, sizeof(*sa6)),
-                    inet_pton(AF_INET6, addr, &sa6->sin6_addr)) {
+
+            if ((uintptr_t)port - (uintptr_t)addr > sizeof(sport->host))
+                goto err;
+            memcpy(sport->host, addr, port - addr);
+        }
+        else if (memset(sa6, 0, sizeof(*sa6)), inet_pton(AF_INET6, addr, &sa6->sin6_addr)){
             sa6->sin6_family = AF_INET6;
             sa6->sin6_port = htons(atoi(port));
-    } else
+
+            if ((uintptr_t)port - (uintptr_t)addr > sizeof(sport->host))
                 goto err;
+            memcpy(sport->host, addr, port - addr);
+        }
+        else if (get_Ip_from_DNS(addr, sport, port, ipv6) != 0)
+            goto err;
+    }
     
     free(addr);
     sport->sp_prog = prog;
     return sport;
 
-  err:
+err:
+    LSQ_ERROR("Couldn't resolve hostname or ip-address");
     free(sport);
     free(addr);
     return NULL;

test/test_common.h

@@ -106,4 +106,13 @@ create_lsquic_reader_ctx (const char *filename);
 void
 destroy_lsquic_reader_ctx (struct reader_ctx *ctx);
 
+/*Function resolves a Hostname into an Ip Adress
+Parameters:
+-hostname	the URL of the website
+-sport      the service port structure that stores the ip
+-port       the port of the connection
+-version	0 for ipv4 and 1 for ipv6
+*/
+int
+get_Ip_from_DNS(const char* hostname, struct service_port * sport, const char* port, int version);
 #endif