From: Martin Willi <martin@strongswan.org>
Date: Thu, 19 Jan 2017 10:23:45 +0000 (+0100)
Subject: kernel-netlink: Use RTA_SRC to specify route source in kernel-based lookups
X-Git-Tag: 5.5.2dr5~17
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=395500b8c1be03a3f2201f7d66e595d13ffcc299;p=thirdparty%2Fstrongswan.git

kernel-netlink: Use RTA_SRC to specify route source in kernel-based lookups

For table dumps the kernel accepts RTA_PREFSRC to filter the routes, which is
what we do when doing userspace route calculations. For kernel-based route
lookups, however, the RTA_PREFSRC attribute is ignored and we must specify
RTA_SRC for policy based route lookups.
---

diff --git a/src/libcharon/plugins/kernel_netlink/kernel_netlink_net.c b/src/libcharon/plugins/kernel_netlink/kernel_netlink_net.c
index 3306956004..2dc76d941c 100644
--- a/src/libcharon/plugins/kernel_netlink/kernel_netlink_net.c
+++ b/src/libcharon/plugins/kernel_netlink/kernel_netlink_net.c
@@ -1883,7 +1883,14 @@ static host_t *get_route(private_kernel_netlink_net_t *this, host_t *dest,
 	if (candidate)
 	{
 		chunk = candidate->get_address(candidate);
-		netlink_add_attribute(hdr, RTA_PREFSRC, chunk, sizeof(request));
+		if (hdr->nlmsg_flags & NLM_F_DUMP)
+		{
+			netlink_add_attribute(hdr, RTA_PREFSRC, chunk, sizeof(request));
+		}
+		else
+		{
+			netlink_add_attribute(hdr, RTA_SRC, chunk, sizeof(request));
+		}
 	}
 	/* we use this below to match against the routes */
 	chunk = dest->get_address(dest);