X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/d6430b975d14ddbd53c40126fa9d00bea3c2d08b..6ee9b735013c0e636b027b77e9f6ba57a96e142f:/winnet.c

diff --git a/winnet.c b/winnet.c
index b5ca7415..9d3f66c2 100644
--- a/winnet.c
+++ b/winnet.c
@@ -55,6 +55,9 @@
 #include "network.h"
 #include "tree234.h"
 
+#define ipv4_is_loopback(addr) \
+	((ntohl(addr.s_addr) & 0xFF000000L) == 0x7F000000L)
+
 struct Socket_tag {
     struct socket_function_table *fn;
     /* the above variable absolutely *must* be the first in this structure */
@@ -654,7 +657,7 @@ Socket sk_new(SockAddr addr, int port, int privport, int oobinline,
     return (Socket) ret;
 }
 
-Socket sk_newlistener(int port, Plug plug, int local_host_only)
+Socket sk_newlistener(char *srcaddr, int port, Plug plug, int local_host_only)
 {
     static struct socket_function_table fn_table = {
 	sk_tcp_plug,
@@ -716,6 +719,8 @@ Socket sk_newlistener(int port, Plug plug, int local_host_only)
 	if (addr->family == AF_INET6) {
 	    memset(&a6, 0, sizeof(a6));
 	    a6.sin6_family = AF_INET6;
+	    /* FIXME: srcaddr is ignored for IPv6, because I (SGT) don't
+	     * know how to do it. :-) */
 	    if (local_host_only)
 		a6.sin6_addr = in6addr_loopback;
 	    else
@@ -724,11 +729,32 @@ Socket sk_newlistener(int port, Plug plug, int local_host_only)
 	} else
 #endif
 	{
+	    int got_addr = 0;
 	    a.sin_family = AF_INET;
-	    if (local_host_only)
-		a.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
-	    else
-		a.sin_addr.s_addr = htonl(INADDR_ANY);
+
+	    /*
+	     * Bind to source address. First try an explicitly
+	     * specified one...
+	     */
+	    if (srcaddr) {
+		a.sin_addr.s_addr = inet_addr(srcaddr);
+		if (a.sin_addr.s_addr != INADDR_NONE) {
+		    /* Override localhost_only with specified listen addr. */
+		    ret->localhost_only = ipv4_is_loopback(a.sin_addr);
+		    got_addr = 1;
+		}
+	    }
+
+	    /*
+	     * ... and failing that, go with one of the standard ones.
+	     */
+	    if (!got_addr) {
+		if (local_host_only)
+		    a.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+		else
+		    a.sin_addr.s_addr = htonl(INADDR_ANY);
+	    }
+
 	    a.sin_port = htons((short)port);
 	}
 #ifdef IPV6
@@ -1047,8 +1073,7 @@ int select_result(WPARAM wParam, LPARAM lParam)
 		    break;
 	    }
 
-	    if (s->localhost_only &&
-		ntohl(isa.sin_addr.s_addr) != INADDR_LOOPBACK) {
+	    if (s->localhost_only && !ipv4_is_loopback(isa.sin_addr)) {
 		closesocket(t);	       /* dodgy WinSock let nonlocal through */
 	    } else if (plug_accepting(s->plug, (void*)t)) {
 		closesocket(t);	       /* denied or error */