7 files changed, 67 insertions, 34 deletions

diff --git a/ChangeLog b/ChangeLog
index 50dfec1d5..574fb449d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -16,6 +16,9 @@
    - markus@cvs.openbsd.org 2001/04/12 19:39:27
      [readconf.c]
      typo
+   - stevesk@cvs.openbsd.org 2001/04/12 20:09:38
+     [misc.c misc.h readconf.c servconf.c ssh.c sshd.c]
+     robust port validation; ok markus@ jakob@
  - (bal) Added openbsd-compat/inet_ntop.[ch] since HP/UX (and others)
    lack it.
 
@@ -5038,4 +5041,4 @@
  - Wrote replacements for strlcpy and mkdtemp
  - Released 1.0pre1
 
-$Id: ChangeLog,v 1.1104 2001/04/12 23:36:05 mouring Exp $
+$Id: ChangeLog,v 1.1105 2001/04/12 23:39:26 mouring Exp $
diff --git a/misc.c b/misc.c
index 495b0290d..feeacb859 100644
--- a/misc.c
+++ b/misc.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: misc.c,v 1.4 2001/02/28 17:52:54 deraadt Exp $        */
+/*      $OpenBSD: misc.c,v 1.5 2001/04/12 20:09:37 stevesk Exp $        */
 
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
@@ -25,7 +25,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: misc.c,v 1.4 2001/02/28 17:52:54 deraadt Exp $");
+RCSID("$OpenBSD: misc.c,v 1.5 2001/04/12 20:09:37 stevesk Exp $");
 
 #include "misc.h"
 #include "log.h"
@@ -116,6 +116,21 @@ pwcopy(struct passwd *pw)
         return copy;
 }
 
+int a2port(const char *s)
+{
+        long port;
+        char *endp;
+
+        errno = 0;
+        port = strtol(s, &endp, 0);
+        if (s == endp || *endp != '\0' ||
+            (errno == ERANGE && (port == LONG_MIN || port == LONG_MAX)) ||
+            port <= 0 || port > 65535)
+                return 0;
+
+        return port;
+}
+
 mysig_t
 mysignal(int sig, mysig_t act)
 {
diff --git a/misc.h b/misc.h
index 3204b626a..2346a5ea5 100644
--- a/misc.h
+++ b/misc.h
@@ -1,4 +1,4 @@
-/*      $OpenBSD: misc.h,v 1.3 2001/02/22 21:59:44 markus Exp $ */
+/*      $OpenBSD: misc.h,v 1.4 2001/04/12 20:09:36 stevesk Exp $        */
 
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -22,6 +22,13 @@ void	set_nonblock(int fd);
 
 struct passwd * pwcopy(struct passwd *pw);
 
+/*
+ * Convert ASCII string to TCP/IP port number.
+ * Port must be >0 and <=65535.
+ * Return 0 if invalid.
+ */
+int a2port(const char *s);
+
 /* wrapper for signal interface */
 typedef void (*mysig_t)(int);
 mysig_t mysignal(int sig, mysig_t act);
diff --git a/readconf.c b/readconf.c
index 144a7602b..241185c65 100644
--- a/readconf.c
+++ b/readconf.c
@@ -12,7 +12,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: readconf.c,v 1.73 2001/04/12 19:39:27 markus Exp $");
+RCSID("$OpenBSD: readconf.c,v 1.74 2001/04/12 20:09:37 stevesk Exp $");
 
 #include "ssh.h"
 #include "xmalloc.h"
@@ -555,10 +555,10 @@ parse_int:
                 arg = strdelim(&s);
                 if (!arg || *arg == '\0')
                         fatal("%.200s line %d: Missing argument.", filename, linenum);
-                if (arg[0] < '0' || arg[0] > '9')
+                fwd_port = a2port(arg);
+                if (fwd_port == 0)
                         fatal("%.200s line %d: Badly formatted port number.",
                               filename, linenum);
-                fwd_port = atoi(arg);
                 arg = strdelim(&s);
                 if (!arg || *arg == '\0')
                         fatal("%.200s line %d: Missing second argument.",
@@ -574,10 +574,10 @@ parse_int:
                 arg = strdelim(&s);
                 if (!arg || *arg == '\0')
                         fatal("%.200s line %d: Missing argument.", filename, linenum);
-                if (arg[0] < '0' || arg[0] > '9')
+                fwd_port = a2port(arg);
+                if (fwd_port == 0)
                         fatal("%.200s line %d: Badly formatted port number.",
                               filename, linenum);
-                fwd_port = atoi(arg);
                 arg = strdelim(&s);
                 if (!arg || *arg == '\0')
                         fatal("%.200s line %d: Missing second argument.",
@@ -594,10 +594,10 @@ parse_int:
                 if (!arg || *arg == '\0')
                         fatal("%.200s line %d: Missing port argument.",
                             filename, linenum);
-                if (arg[0] < '0' || arg[0] > '9')
+                fwd_port = a2port(arg);
+                if (fwd_port == 0)
                         fatal("%.200s line %d: Badly formatted port number.",
                             filename, linenum);
-                fwd_port = atoi(arg);
                 add_local_forward(options, fwd_port, "socks4", 0);
                 break;
 
diff --git a/servconf.c b/servconf.c
index 8e876d1f1..f3d5068c0 100644
--- a/servconf.c
+++ b/servconf.c
@@ -10,7 +10,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: servconf.c,v 1.75 2001/04/12 19:15:25 markus Exp $");
+RCSID("$OpenBSD: servconf.c,v 1.76 2001/04/12 20:09:37 stevesk Exp $");
 
 #ifdef KRB4
 #include <krb.h>
@@ -31,8 +31,7 @@ RCSID("$OpenBSD: servconf.c,v 1.75 2001/04/12 19:15:25 markus Exp $");
 #include "kex.h"
 #include "mac.h"
 
-/* add listen address */
-void add_listen_addr(ServerOptions *options, char *addr, char *port);
+void add_listen_addr(ServerOptions *options, char *addr, u_short port);
 void add_one_listen_addr(ServerOptions *options, char *addr, u_short port);
 
 /* AF_UNSPEC or AF_INET or AF_INET6 */
@@ -117,7 +116,7 @@ fill_default_server_options(ServerOptions *options)
         if (options->num_ports == 0)
                 options->ports[options->num_ports++] = SSH_DEFAULT_PORT;
         if (options->listen_addrs == NULL)
-                add_listen_addr(options, NULL, NULL);
+                add_listen_addr(options, NULL, 0);
         if (options->pid_file == NULL)
                 options->pid_file = _PATH_SSH_DAEMON_PID_FILE;
         if (options->server_key_bits == -1)
@@ -312,21 +311,18 @@ parse_token(const char *cp, const char *filename,
         return sBadOption;
 }
 
-/*
- * add listen address
- */
 void
-add_listen_addr(ServerOptions *options, char *addr, char *port)
+add_listen_addr(ServerOptions *options, char *addr, u_short port)
 {
         int i;
 
         if (options->num_ports == 0)
                 options->ports[options->num_ports++] = SSH_DEFAULT_PORT;
-        if (port == NULL)
+        if (port == 0)
                 for (i = 0; i < options->num_ports; i++)
                         add_one_listen_addr(options, addr, options->ports[i]);
         else
-                add_one_listen_addr(options, addr, atoi(port));
+                add_one_listen_addr(options, addr, port);
 }
 
 void
@@ -400,7 +396,10 @@ read_server_config(ServerOptions *options, const char *filename)
                         if (!arg || *arg == '\0')
                                 fatal("%s line %d: missing port number.",
                                     filename, linenum);
-                        options->ports[options->num_ports++] = atoi(arg);
+                        options->ports[options->num_ports++] = a2port(arg);
+                        if (options->ports[options->num_ports-1] == 0)
+                                fatal("%s line %d: Badly formatted port number.",
+                                    filename, linenum);
                         break;
 
                 case sServerKeyBits:
@@ -438,20 +437,25 @@ parse_int:
                                 memmove(p, p+1, strlen(p+1)+1);
                         } else if (((p = strchr(arg, ':')) == NULL) ||
                                     (strchr(p+1, ':') != NULL)) {
-                                add_listen_addr(options, arg, NULL);
+                                add_listen_addr(options, arg, 0);
                                 break;
                         }
                         if (*p == ':') {
+                                u_short port;
+
                                 p++;
                                 if (*p == '\0')
                                         fatal("%s line %d: bad inet addr:port usage.",
                                             filename, linenum);
                                 else {
                                         *(p-1) = '\0';
-                                        add_listen_addr(options, arg, p);
+                                        if ((port = a2port(p)) == 0)
+                                                fatal("%s line %d: bad port number.",
+                                                    filename, linenum);
+                                        add_listen_addr(options, arg, port);
                                 }
                         } else if (*p == '\0')
-                                add_listen_addr(options, arg, NULL);
+                                add_listen_addr(options, arg, 0);
                         else
                                 fatal("%s line %d: bad inet addr usage.",
                                     filename, linenum);
diff --git a/ssh.c b/ssh.c
index f14fbac23..eda443751 100644
--- a/ssh.c
+++ b/ssh.c
@@ -39,7 +39,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: ssh.c,v 1.112 2001/04/12 19:15:25 markus Exp $");
+RCSID("$OpenBSD: ssh.c,v 1.113 2001/04/12 20:09:37 stevesk Exp $");
 
 #include <openssl/evp.h>
 #include <openssl/err.h>
@@ -247,7 +247,7 @@ main(int ac, char **av)
 {
         int i, opt, optind, exit_status, ok;
         u_short fwd_port, fwd_host_port;
-        char *optarg, *cp, *endofnumber, buf[256];
+        char *optarg, *cp, buf[256];
         struct stat st;
         struct passwd *pw;
         int dummy;
@@ -460,8 +460,8 @@ main(int ac, char **av)
                         }
                         break;
                 case 'p':
-                        options.port = strtol(optarg, &endofnumber, 0);
-                        if (optarg == endofnumber) {
+                        options.port = a2port(optarg);
+                        if (options.port == 0) {
                                 fprintf(stderr, "Bad port '%s'\n", optarg);
                                 exit(1);
                         }
@@ -493,9 +493,9 @@ main(int ac, char **av)
                         break;
 
                 case 'D':
-                        fwd_port = strtol(optarg, &endofnumber, 0);
-                        if (optarg == endofnumber) {
-                                fprintf(stderr, "Bad port '%s'\n", optarg);
+                        fwd_port = a2port(optarg);
+                        if (fwd_port == 0) {
+                                fprintf(stderr, "Bad dynamic port '%s'\n", optarg);
                                 exit(1);
                         }
                         add_local_forward(&options, fwd_port, "socks4", 0);
diff --git a/sshd.c b/sshd.c
index bde1ac344..eaf3d322a 100644
--- a/sshd.c
+++ b/sshd.c
@@ -40,7 +40,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: sshd.c,v 1.192 2001/04/11 16:25:30 lebel Exp $");
+RCSID("$OpenBSD: sshd.c,v 1.193 2001/04/12 20:09:38 stevesk Exp $");
 
 #include <openssl/dh.h>
 #include <openssl/bn.h>
@@ -611,7 +611,11 @@ main(int ac, char **av)
                                 fprintf(stderr, "too many ports.\n");
                                 exit(1);
                         }
-                        options.ports[options.num_ports++] = atoi(optarg);
+                        options.ports[options.num_ports++] = a2port(optarg);
+                        if (options.ports[options.num_ports-1] == 0) {
+                                fprintf(stderr, "Bad port number.\n");
+                                exit(1);
+                        }
                         break;
                 case 'g':
                         options.login_grace_time = atoi(optarg);