From 46f258147c57d2320fa05ecf108db22854bef13f Mon Sep 17 00:00:00 2001
From: simon <simon@cda61777-01e9-0310-a592-d414129be87e>
Date: Tue, 16 Oct 2012 20:15:51 +0000
Subject: [PATCH] If you configure Unix PuTTY to use a proxy, tell it to even
 proxy localhost connections, and also enable X forwarding in such a way that
 it will attempt to connect to a Unix-domain X server socket, an assertion
 will fail when proxy_for_destination() tries to call sk_getaddr(). Fix by
 ensuring that Unix-domain sockets are _never_ proxied, since they
 fundamentally can't be.

git-svn-id: svn://svn.tartarus.org/sgt/putty@9688 cda61777-01e9-0310-a592-d414129be87e
---
 network.h        | 1 +
 proxy.c          | 9 +++++++++
 unix/uxnet.c     | 5 +++++
 windows/winnet.c | 5 +++++
 4 files changed, 20 insertions(+)

diff --git a/network.h b/network.h
index 45f4e2a7..49ebd39c 100644
--- a/network.h
+++ b/network.h
@@ -118,6 +118,7 @@ SockAddr sk_nonamelookup(const char *host);
 void sk_getaddr(SockAddr addr, char *buf, int buflen);
 int sk_hostname_is_local(char *name);
 int sk_address_is_local(SockAddr addr);
+int sk_address_is_special_local(SockAddr addr);
 int sk_addrtype(SockAddr addr);
 void sk_addrcopy(SockAddr addr, char *buf);
 void sk_addr_free(SockAddr addr);
diff --git a/proxy.c b/proxy.c
index 051beb7e..3c81884d 100644
--- a/proxy.c
+++ b/proxy.c
@@ -286,6 +286,15 @@ static int proxy_for_destination (SockAddr addr, char *hostname, int port,
     const char *exclude_list;
 
     /*
+     * Special local connections such as Unix-domain sockets
+     * unconditionally cannot be proxied, even in proxy-localhost
+     * mode. There just isn't any way to ask any known proxy type for
+     * them.
+     */
+    if (addr && sk_address_is_special_local(addr))
+        return 0;                      /* do not proxy */
+
+    /*
      * Check the host name and IP against the hard-coded
      * representations of `localhost'.
      */
diff --git a/unix/uxnet.c b/unix/uxnet.c
index e2302aa4..fef4c43c 100644
--- a/unix/uxnet.c
+++ b/unix/uxnet.c
@@ -390,6 +390,11 @@ int sk_address_is_local(SockAddr addr)
     }
 }
 
+int sk_address_is_special_local(SockAddr addr)
+{
+    return addr->superfamily == UNIX;
+}
+
 int sk_addrtype(SockAddr addr)
 {
     SockAddrStep step;
diff --git a/windows/winnet.c b/windows/winnet.c
index 84b239c0..2088f9d7 100644
--- a/windows/winnet.c
+++ b/windows/winnet.c
@@ -667,6 +667,11 @@ int sk_address_is_local(SockAddr addr)
     }
 }
 
+int sk_address_is_special_local(SockAddr addr)
+{
+    return 0;                /* no Unix-domain socket analogue here */
+}
+
 int sk_addrtype(SockAddr addr)
 {
     SockAddrStep step;
-- 
2.11.0