openssh unix dev - Jun 2001 - [PATCH] Make "-L" local ports bind to "127.0.0.1" in openssh-2.9p1

On Sat, Jun 09, 2001 at 07:48:06PM -0400, Albert John FitzPatrick III
wrote:
> +	 * Oh yeah?  Setting hostname to NULL and hints.ai_flags to
> +	 * AI_PASSIVE on Red Hat Linux release 6.0 (Hedwig) with
> +	 * Linux kernel 2.2.14 does no such thing.  On that system
> +	 * "::" and "0.0.0.0" (and maybe one other value
which slips
> +	 * my memory) are returned.  Setting hostname to "127.0.0.1"
> +	 * does the trick, at least for IPv4 uses; I don't know what
> +	 * it does for IPv6.  Without this hack, local ("-L") tunnel
> +	 * end-points (which are supposed to be private unless "-g"
> +	 * or "-o 'GatewayPorts yes'" is specified when
"ssh" is
> +	 * started) are [ab]usable by any host which has a route
> +	 * to/from the this host.
Perhaps you should point your operating system vendor (or whomever they
get their libc from) at RFC 2553:

   If the AI_PASSIVE bit is not set in the ai_flags member of the hints
   structure, then the returned socket address structure will be ready
   for a call to connect() (for a connection-oriented protocol) or
   either connect(), sendto(), or sendmsg() (for a connectionless
   protocol).  In this case, if the nodename argument is a NULL pointer,
   then the IP address portion of the socket address structure will be
   set to the loopback address.

-- 
David Terrell            | "... a grandiose, wasteful drug war that will
never
dbt at meat.net             | be won as long as so many Americans need to 
Nebcorp Prime Minister   | anesthetize themselves to get through the day." 
http://wwn.nebcorp.com/  |  -Camille Paglia

can anyone confirm this broken linux behaviour?

On Sat, Jun 09, 2001 at 07:48:06PM -0400, Albert John FitzPatrick III
wrote:
> diff -u -r -N openssh-2.9p1/channels.c openssh-2.9p1-ajf.1/channels.c
> --- openssh-2.9p1/channels.c	Tue Apr 17 14:14:35 2001
> +++ openssh-2.9p1-ajf.1/channels.c	Wed Jun  6 23:25:36 2001
> @@ -1815,13 +1815,25 @@
>  	/*
>  	 * getaddrinfo returns a loopback address if the hostname is
>  	 * set to NULL and hints.ai_flags is not AI_PASSIVE
> +	 *
> +	 * Oh yeah?  Setting hostname to NULL and hints.ai_flags to
> +	 * AI_PASSIVE on Red Hat Linux release 6.0 (Hedwig) with
> +	 * Linux kernel 2.2.14 does no such thing.  On that system
> +	 * "::" and "0.0.0.0" (and maybe one other value
which slips
> +	 * my memory) are returned.  Setting hostname to "127.0.0.1"
> +	 * does the trick, at least for IPv4 uses; I don't know what
> +	 * it does for IPv6.  Without this hack, local ("-L") tunnel
> +	 * end-points (which are supposed to be private unless "-g"
> +	 * or "-o 'GatewayPorts yes'" is specified when
"ssh" is
> +	 * started) are [ab]usable by any host which has a route
> +	 * to/from the this host.
>  	 */
>  	memset(&hints, 0, sizeof(hints));
>  	hints.ai_family = IPv4or6;
>  	hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
>  	hints.ai_socktype = SOCK_STREAM;
>  	snprintf(strport, sizeof strport, "%d", listen_port);
> -	if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
> +	if (getaddrinfo(gateway_ports ? NULL : "127.0.0.1", strport,
&hints, &aitop) != 0)
>  		packet_disconnect("getaddrinfo: fatal error");
>  
>  	for (ai = aitop; ai; ai = ai->ai_next) {
> 
>

diff -u -r -N openssh-2.9p1/channels.c openssh-2.9p1-ajf.1/channels.c
--- openssh-2.9p1/channels.c	Tue Apr 17 14:14:35 2001
+++ openssh-2.9p1-ajf.1/channels.c	Wed Jun  6 23:25:36 2001
@@ -1815,13 +1815,25 @@
 	/*
 	 * getaddrinfo returns a loopback address if the hostname is
 	 * set to NULL and hints.ai_flags is not AI_PASSIVE
+	 *
+	 * Oh yeah?  Setting hostname to NULL and hints.ai_flags to
+	 * AI_PASSIVE on Red Hat Linux release 6.0 (Hedwig) with
+	 * Linux kernel 2.2.14 does no such thing.  On that system
+	 * "::" and "0.0.0.0" (and maybe one other value which
slips
+	 * my memory) are returned.  Setting hostname to "127.0.0.1"
+	 * does the trick, at least for IPv4 uses; I don't know what
+	 * it does for IPv6.  Without this hack, local ("-L") tunnel
+	 * end-points (which are supposed to be private unless "-g"
+	 * or "-o 'GatewayPorts yes'" is specified when
"ssh" is
+	 * started) are [ab]usable by any host which has a route
+	 * to/from the this host.
 	 */
 	memset(&hints, 0, sizeof(hints));
 	hints.ai_family = IPv4or6;
 	hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
 	hints.ai_socktype = SOCK_STREAM;
 	snprintf(strport, sizeof strport, "%d", listen_port);
-	if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
+	if (getaddrinfo(gateway_ports ? NULL : "127.0.0.1", strport,
&hints, &aitop) != 0)
 		packet_disconnect("getaddrinfo: fatal error");
 
 	for (ai = aitop; ai; ai = ai->ai_next) {