upstream: Support using service names for port numbers.

* Try to resolve a port specification with getservbyname(3) if a
 numeric conversion fails.
* Make the "Port" option in ssh_config handle its argument as a
 port rather than a plain integer.

ok dtucker@ deraadt@

OpenBSD-Commit-ID: e7f03633133205ab3dfbc67f9df7475fabae660d

2 files changed, 23 insertions, 10 deletions

diff --git a/misc.c b/misc.c
index c4ca12560..bdc06fdb3 100644
--- a/misc.c
+++ b/misc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: misc.c,v 1.132 2018/10/03 06:38:35 djm Exp $ */
+/* $OpenBSD: misc.c,v 1.133 2018/10/05 14:26:09 naddy Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  * Copyright (c) 2005,2006 Damien Miller.  All rights reserved.
@@ -50,6 +50,7 @@
 #include <netinet/in_systm.h>
 #include <netinet/ip.h>
 #include <netinet/tcp.h>
+#include <arpa/inet.h>
 
 #include <ctype.h>
 #include <errno.h>
@@ -332,13 +333,16 @@ pwcopy(struct passwd *pw)
 int
 a2port(const char *s)
 {
+        struct servent *se;
         long long port;
         const char *errstr;
 
         port = strtonum(s, 0, 65535, &errstr);
-        if (errstr != NULL)
-                return -1;
-        return (int)port;
+        if (errstr == NULL)
+                return (int)port;
+        if ((se = getservbyname(s, "tcp")) != NULL)
+                return ntohs(se->s_port);
+        return -1;
 }
 
 int
diff --git a/readconf.c b/readconf.c
index d39cfa3c5..433811521 100644
--- a/readconf.c
+++ b/readconf.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: readconf.c,v 1.299 2018/10/03 06:38:35 djm Exp $ */
+/* $OpenBSD: readconf.c,v 1.300 2018/10/05 14:26:09 naddy Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -1158,7 +1158,20 @@ parse_command:
                 return 0;
 
         case oPort:
-                intptr = &options->port;
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing argument.",
+                            filename, linenum);
+                value = a2port(arg);
+                if (value <= 0)
+                        fatal("%.200s line %d: Bad port '%s'.",
+                            filename, linenum, arg);
+                if (*activep && options->port == -1)
+                        options->port = value;
+                break;
+
+        case oConnectionAttempts:
+                intptr = &options->connection_attempts;
 parse_int:
                 arg = strdelim(&s);
                 if ((errstr = atoi_err(arg, &value)) != NULL)
@@ -1168,10 +1181,6 @@ parse_int:
                         *intptr = value;
                 break;
 
-        case oConnectionAttempts:
-                intptr = &options->connection_attempts;
-                goto parse_int;
-
         case oCiphers:
                 arg = strdelim(&s);
                 if (!arg || *arg == '\0')