upstream: Remove uid checks from low port binds. Now that ssh

cannot be setuid and sshd always has privsep on, we can remove the uid checks
for low port binds and just let the system do the check. We leave a sanity
check for the !privsep case so long as the code is stil there.  with & ok
djm@

OpenBSD-Commit-ID: 9535cfdbd1cd54486fdbedfaee44ce4367ec7ca0

4 files changed, 15 insertions, 17 deletions

diff --git a/misc.c b/misc.c
index 6b093f21b..ae4d29b84 100644
--- a/misc.c
+++ b/misc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: misc.c,v 1.130 2018/07/18 11:34:04 dtucker Exp $ */
+/* $OpenBSD: misc.c,v 1.131 2018/07/27 05:13:02 dtucker Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  * Copyright (c) 2005,2006 Damien Miller.  All rights reserved.
@@ -1576,15 +1576,6 @@ forward_equals(const struct Forward *a, const struct Forward *b)
         return 1;
 }
 
-/* returns 1 if bind to specified port by specified user is permitted */
-int
-bind_permitted(int port, uid_t uid)
-{
-        if (port < IPPORT_RESERVED && uid != 0)
-                return 0;
-        return 1;
-}
-
 /* returns 1 if process is already daemonized, 0 otherwise */
 int
 daemonized(void)
diff --git a/misc.h b/misc.h
index 837b005aa..6be289fd2 100644
--- a/misc.h
+++ b/misc.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: misc.h,v 1.73 2018/06/09 03:01:12 djm Exp $ */
+/* $OpenBSD: misc.h,v 1.74 2018/07/27 05:13:02 dtucker Exp $ */
 
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -31,7 +31,6 @@ struct Forward {
 };
 
 int forward_equals(const struct Forward *, const struct Forward *);
-int bind_permitted(int, uid_t);
 int daemonized(void);
 
 /* Common server and client forwarding options. */
diff --git a/readconf.c b/readconf.c
index ce832526a..d9b6e4cf9 100644
--- a/readconf.c
+++ b/readconf.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: readconf.c,v 1.294 2018/07/19 10:28:47 dtucker Exp $ */
+/* $OpenBSD: readconf.c,v 1.295 2018/07/27 05:13:02 dtucker Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -323,9 +323,6 @@ add_local_forward(Options *options, const struct Forward *newfwd)
         extern uid_t original_real_uid;
         int i;
 
-        if (!bind_permitted(newfwd->listen_port, original_real_uid) &&
-            newfwd->listen_path == NULL)
-                fatal("Privileged ports can only be forwarded by root.");
         /* Don't add duplicates */
         for (i = 0; i < options->num_local_forwards; i++) {
                 if (forward_equals(newfwd, options->local_forwards + i))
diff --git a/serverloop.c b/serverloop.c
index cf18e387e..7be83e2d3 100644
--- a/serverloop.c
+++ b/serverloop.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: serverloop.c,v 1.208 2018/07/11 18:53:29 markus Exp $ */
+/* $OpenBSD: serverloop.c,v 1.209 2018/07/27 05:13:02 dtucker Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -103,6 +103,17 @@ static void server_init_dispatch(void);
 /* requested tunnel forwarding interface(s), shared with session.c */
 char *tun_fwd_ifnames = NULL;
 
+/* returns 1 if bind to specified port by specified user is permitted */
+static int
+bind_permitted(int port, uid_t uid)
+{
+        if (use_privsep)
+                return 1; /* allow system to decide */
+        if (port < IPPORT_RESERVED && uid != 0)
+                return 0;
+        return 1;
+}
+
 /*
  * we write to this pipe if a SIGCHLD is caught in order to avoid
  * the race between select() and child_terminated