1 files changed, 119 insertions, 38 deletions

diff --git a/readconf.c b/readconf.c
index a4fe1fe02..c3dc71e66 100644
--- a/readconf.c
+++ b/readconf.c
@@ -12,7 +12,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: readconf.c,v 1.134 2004/07/11 17:48:47 deraadt Exp $");
+RCSID("$OpenBSD: readconf.c,v 1.135 2005/03/01 10:09:52 djm Exp $");
 
 #include "ssh.h"
 #include "xmalloc.h"
@@ -206,21 +206,23 @@ static struct {
  */
 
 void
-add_local_forward(Options *options, u_short port, const char *host,
-                  u_short host_port)
+add_local_forward(Options *options, const Forward *newfwd)
 {
         Forward *fwd;
 #ifndef NO_IPPORT_RESERVED_CONCEPT
         extern uid_t original_real_uid;
-        if (port < IPPORT_RESERVED && original_real_uid != 0)
+        if (newfwd->listen_port < IPPORT_RESERVED && original_real_uid != 0)
                 fatal("Privileged ports can only be forwarded by root.");
 #endif
         if (options->num_local_forwards >= SSH_MAX_FORWARDS_PER_DIRECTION)
                 fatal("Too many local forwards (max %d).", SSH_MAX_FORWARDS_PER_DIRECTION);
         fwd = &options->local_forwards[options->num_local_forwards++];
-        fwd->port = port;
-        fwd->host = xstrdup(host);
-        fwd->host_port = host_port;
+
+        fwd->listen_host = (newfwd->listen_host == NULL) ?
+            NULL : xstrdup(newfwd->listen_host);
+        fwd->listen_port = newfwd->listen_port;
+        fwd->connect_host = xstrdup(newfwd->connect_host);
+        fwd->connect_port = newfwd->connect_port;
 }
 
 /*
@@ -229,17 +231,19 @@ add_local_forward(Options *options, u_short port, const char *host,
  */
 
 void
-add_remote_forward(Options *options, u_short port, const char *host,
-                   u_short host_port)
+add_remote_forward(Options *options, const Forward *newfwd)
 {
         Forward *fwd;
         if (options->num_remote_forwards >= SSH_MAX_FORWARDS_PER_DIRECTION)
                 fatal("Too many remote forwards (max %d).",
                     SSH_MAX_FORWARDS_PER_DIRECTION);
         fwd = &options->remote_forwards[options->num_remote_forwards++];
-        fwd->port = port;
-        fwd->host = xstrdup(host);
-        fwd->host_port = host_port;
+
+        fwd->listen_host = (newfwd->listen_host == NULL) ?
+            NULL : xstrdup(newfwd->listen_host);
+        fwd->listen_port = newfwd->listen_port;
+        fwd->connect_host = xstrdup(newfwd->connect_host);
+        fwd->connect_port = newfwd->connect_port;
 }
 
 static void
@@ -247,11 +251,15 @@ clear_forwardings(Options *options)
 {
         int i;
 
-        for (i = 0; i < options->num_local_forwards; i++)
-                xfree(options->local_forwards[i].host);
+        for (i = 0; i < options->num_local_forwards; i++) {
+                xfree(options->local_forwards[i].listen_host);
+                xfree(options->local_forwards[i].connect_host);
+        }
         options->num_local_forwards = 0;
-        for (i = 0; i < options->num_remote_forwards; i++)
-                xfree(options->remote_forwards[i].host);
+        for (i = 0; i < options->num_remote_forwards; i++) {
+                xfree(options->remote_forwards[i].listen_host);
+                xfree(options->remote_forwards[i].connect_host);
+        }
         options->num_remote_forwards = 0;
 }
 
@@ -284,11 +292,10 @@ process_config_line(Options *options, const char *host,
                     char *line, const char *filename, int linenum,
                     int *activep)
 {
-        char buf[256], *s, **charptr, *endofnumber, *keyword, *arg;
+        char *s, **charptr, *endofnumber, *keyword, *arg, *arg2, fwdarg[256];
         int opcode, *intptr, value;
         size_t len;
-        u_short fwd_port, fwd_host_port;
-        char sfwd_host_port[6];
+        Forward fwd;
 
         /* Strip trailing whitespace */
         for(len = strlen(line) - 1; len > 0; len--) {
@@ -645,30 +652,26 @@ parse_int:
         case oLocalForward:
         case oRemoteForward:
                 arg = strdelim(&s);
-                if (!arg || *arg == '\0')
+                if (arg == NULL || *arg == '\0')
                         fatal("%.200s line %d: Missing port argument.",
                             filename, linenum);
-                if ((fwd_port = a2port(arg)) == 0)
-                        fatal("%.200s line %d: Bad listen port.",
+                arg2 = strdelim(&s);
+                if (arg2 == NULL || *arg2 == '\0')
+                        fatal("%.200s line %d: Missing target argument.",
                             filename, linenum);
-                arg = strdelim(&s);
-                if (!arg || *arg == '\0')
-                        fatal("%.200s line %d: Missing second argument.",
-                            filename, linenum);
-                if (sscanf(arg, "%255[^:]:%5[0-9]", buf, sfwd_host_port) != 2 &&
-                    sscanf(arg, "%255[^/]/%5[0-9]", buf, sfwd_host_port) != 2)
+
+                /* construct a string for parse_forward */
+                snprintf(fwdarg, sizeof(fwdarg), "%s:%s", arg, arg2);
+
+                if (parse_forward(&fwd, fwdarg) == 0)
                         fatal("%.200s line %d: Bad forwarding specification.",
                             filename, linenum);
-                if ((fwd_host_port = a2port(sfwd_host_port)) == 0)
-                        fatal("%.200s line %d: Bad forwarding port.",
-                            filename, linenum);
+
                 if (*activep) {
                         if (opcode == oLocalForward)
-                                add_local_forward(options, fwd_port, buf,
-                                    fwd_host_port);
+                                add_local_forward(options, &fwd);
                         else if (opcode == oRemoteForward)
-                                add_remote_forward(options, fwd_port, buf,
-                                    fwd_host_port);
+                                add_remote_forward(options, &fwd);
                 }
                 break;
 
@@ -677,12 +680,25 @@ parse_int:
                 if (!arg || *arg == '\0')
                         fatal("%.200s line %d: Missing port argument.",
                             filename, linenum);
-                fwd_port = a2port(arg);
-                if (fwd_port == 0)
+                memset(&fwd, '\0', sizeof(fwd));
+                fwd.connect_host = "socks";
+                fwd.listen_host = hpdelim(&arg);
+                if (fwd.listen_host == NULL ||
+                    strlen(fwd.listen_host) >= NI_MAXHOST)
+                        fatal("%.200s line %d: Bad forwarding specification.",
+                            filename, linenum);
+                if (arg) {
+                        fwd.listen_port = a2port(arg);
+                        fwd.listen_host = cleanhostname(fwd.listen_host);
+                } else {
+                        fwd.listen_port = a2port(fwd.listen_host);
+                        fwd.listen_host = "";
+                }
+                if (fwd.listen_port == 0)
                         fatal("%.200s line %d: Badly formatted port number.",
                             filename, linenum);
                 if (*activep)
-                        add_local_forward(options, fwd_port, "socks", 0);
+                        add_local_forward(options, &fwd);
                 break;
 
         case oClearAllForwardings:
@@ -1045,3 +1061,68 @@ fill_default_options(Options * options)
         /* options->host_key_alias should not be set by default */
         /* options->preferred_authentications will be set in ssh */
 }
+
+/*
+ * parse_forward
+ * parses a string containing a port forwarding specification of the form:
+ *      [listenhost:]listenport:connecthost:connectport
+ * returns number of arguments parsed or zero on error
+ */
+int
+parse_forward(Forward *fwd, const char *fwdspec)
+{
+        int i;
+        char *p, *cp, *fwdarg[4];
+
+        memset(fwd, '\0', sizeof(*fwd));
+
+        cp = p = xstrdup(fwdspec);
+
+        /* skip leading spaces */
+        while (*cp && isspace(*cp))
+                cp++;
+
+        for (i = 0; i < 4; ++i)
+                if ((fwdarg[i] = hpdelim(&cp)) == NULL)
+                        break;
+
+        /* Check for trailing garbage in 4-arg case*/
+        if (cp != NULL)
+                i = 0;  /* failure */
+
+        switch (i) {
+        case 3:
+                fwd->listen_host = NULL;
+                fwd->listen_port = a2port(fwdarg[0]);
+                fwd->connect_host = xstrdup(cleanhostname(fwdarg[1]));
+                fwd->connect_port = a2port(fwdarg[2]);
+                break;
+
+        case 4:
+                fwd->listen_host = xstrdup(cleanhostname(fwdarg[0]));
+                fwd->listen_port = a2port(fwdarg[1]);
+                fwd->connect_host = xstrdup(cleanhostname(fwdarg[2]));
+                fwd->connect_port = a2port(fwdarg[3]);
+                break;
+        default:
+                i = 0; /* failure */
+        }
+
+        xfree(p);
+
+        if (fwd->listen_port == 0 && fwd->connect_port == 0)
+                goto fail_free;
+
+        if (fwd->connect_host != NULL &&
+            strlen(fwd->connect_host) >= NI_MAXHOST)
+                goto fail_free;
+
+        return (i);
+
+ fail_free:
+        if (fwd->connect_host != NULL)
+                xfree(fwd->connect_host);
+        if (fwd->listen_host != NULL)
+                xfree(fwd->listen_host);
+        return (0);
+}