>From bfebe7fc838f83065fea04cf27613fe89e962a3a Mon Sep 17 00:00:00 2001
From: Bignaux Ronan <ronan@aimao.org>
Date: Thu, 20 Sep 2012 15:09:31 +0200
Subject: [PATCH] add option to bind to a specific interface


Signed-off-by: Bignaux Ronan <ronan@aimao.org>
---
 daemon.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/daemon.c b/daemon.c
index 4602b46..755fbd3 100644
--- a/daemon.c
+++ b/daemon.c
@@ -5,6 +5,10 @@
 #include "strbuf.h"
 #include "string-list.h"
 
+#ifdef SO_BINDTODEVICE
+#include <net/if.h>
+#endif
+
 #ifndef HOST_NAME_MAX
 #define HOST_NAME_MAX 256
 #endif
@@ -31,7 +35,7 @@ static const char daemon_usage[] =
 "           [--reuseaddr] [--pid-file=<file>]\n"
 "           [--(enable|disable|allow-override|forbid-override)=<service>]\n"
 "           [--access-hook=<path>]\n"
-"           [--inetd | [--listen=<host_or_ipaddr>] [--port=<n>]\n"
+"           [--inetd | [--listen=<host_or_ipaddr>] [--port=<n>] [--bindtodev=<interface>]\n"
 "                      [--detach] [--user=<user> [--group=<group>]]\n"
 "           [<directory>...]";
 
@@ -64,6 +68,7 @@ static char *hostname;
 static char *canon_hostname;
 static char *ip_address;
 static char *tcp_port;
+static struct ifreq ifr;
 
 static void logreport(int priority, const char *err, va_list params)
 {
@@ -875,6 +880,15 @@ static int setup_named_sock(char *listen_addr, int listen_port, struct socketlis
 			continue;
 		}
 
+		if (ifr.ifr_name) {
+			if (setsockopt(sockfd, SOL_SOCKET, SO_BINDTODEVICE, (void *) &ifr,
+					sizeof(ifr)) < 0) {
+				logerror("Could not set SO_BINDTODEVICE: %s", strerror(errno));
+				close(sockfd);
+				continue;
+			}
+		}
+
 #ifdef IPV6_V6ONLY
 		if (ai->ai_family == AF_INET6) {
 			int on = 1;
@@ -1194,6 +1208,11 @@ int main(int argc, char **argv)
 				continue;
 			}
 		}
+		if (!prefixcmp(arg, "--bindtodev=")) {
+			memset(&ifr, 0, sizeof(ifr));
+			strncpy (ifr.ifr_name, arg + 12 ,IFNAMSIZ);
+			continue;
+		}
 		if (!strcmp(arg, "--serve")) {
 			serve_mode = 1;
 			continue;
-- 
1.7.12