Now that we have IP_SENDSRCADDR, add sendtofrom().

Ok jca@ and reyk@

3 files changed, 71 insertions, 14 deletions

diff --git a/sbin/iked/iked.h b/sbin/iked/iked.h
index 6a6a3885bf2..f8c44fdd77f 100644
--- a/sbin/iked/iked.h
+++ b/sbin/iked/iked.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: iked.h,v 1.97 2016/09/03 09:20:07 vgross Exp $	*/
+/*	$OpenBSD: iked.h,v 1.98 2016/09/04 10:26:02 vgross Exp $	*/
 
 /*
  * Copyright (c) 2010-2013 Reyk Floeter <reyk@openbsd.org>
@@ -899,6 +899,8 @@ int	 socket_setport(struct sockaddr *, in_port_t);
 int	 socket_getaddr(int, struct sockaddr_storage *);
 int	 socket_bypass(int, struct sockaddr *);
 int	 udp_bind(struct sockaddr *, in_port_t);
+ssize_t	 sendtofrom(int, void *, size_t, int, struct sockaddr *,
+	    socklen_t, struct sockaddr *, socklen_t);
 ssize_t	 recvfromto(int, void *, size_t, int, struct sockaddr *,
 	    socklen_t *, struct sockaddr *, socklen_t *);
 const char *
diff --git a/sbin/iked/ikev2_msg.c b/sbin/iked/ikev2_msg.c
index 3fe71563752..c03bab11aa0 100644
--- a/sbin/iked/ikev2_msg.c
+++ b/sbin/iked/ikev2_msg.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ikev2_msg.c,v 1.45 2015/10/19 11:25:35 reyk Exp $	*/
+/*	$OpenBSD: ikev2_msg.c,v 1.46 2016/09/04 10:26:02 vgross Exp $	*/
 
 /*
  * Copyright (c) 2010-2013 Reyk Floeter <reyk@openbsd.org>
@@ -319,9 +319,10 @@ ikev2_msg_send(struct iked *env, struct iked_message *msg)
 		msg->msg_offset += sizeof(natt);
 	}
 
-	if ((sendto(msg->msg_fd, ibuf_data(buf), ibuf_size(buf), 0,
-	    (struct sockaddr *)&msg->msg_peer, msg->msg_peerlen)) == -1) {
-		log_warn("%s: sendto", __func__);
+	if (sendtofrom(msg->msg_fd, ibuf_data(buf), ibuf_size(buf), 0,
+	    (struct sockaddr *)&msg->msg_peer, msg->msg_peerlen,
+	    (struct sockaddr *)&msg->msg_local, msg->msg_locallen) == -1) {
+		log_warn("%s: sendtofrom", __func__);
 		return (-1);
 	}
 
@@ -969,10 +970,11 @@ int
 ikev2_msg_retransmit_response(struct iked *env, struct iked_sa *sa,
     struct iked_message *msg)
 {
-	if ((sendto(msg->msg_fd, ibuf_data(msg->msg_data),
-	    ibuf_size(msg->msg_data), 0, (struct sockaddr *)&msg->msg_peer,
-	    msg->msg_peerlen)) == -1) {
-		log_warn("%s: sendto", __func__);
+	if (sendtofrom(msg->msg_fd, ibuf_data(msg->msg_data),
+	    ibuf_size(msg->msg_data), 0,
+	    (struct sockaddr *)&msg->msg_peer, msg->msg_peerlen,
+	    (struct sockaddr *)&msg->msg_local, msg->msg_locallen) == -1) {
+		log_warn("%s: sendtofrom", __func__);
 		return (-1);
 	}
 
@@ -996,11 +998,12 @@ ikev2_msg_retransmit_timeout(struct iked *env, void *arg)
 	struct iked_sa		*sa = msg->msg_sa;
 
 	if (msg->msg_tries < IKED_RETRANSMIT_TRIES) {
-		if ((sendto(msg->msg_fd, ibuf_data(msg->msg_data),
+		if (sendtofrom(msg->msg_fd, ibuf_data(msg->msg_data),
 		    ibuf_size(msg->msg_data), 0,
-		    (struct sockaddr *)&msg->msg_peer,
-		    msg->msg_peerlen)) == -1) {
-			log_warn("%s: sendto", __func__);
+		    (struct sockaddr *)&msg->msg_peer, msg->msg_peerlen,
+		    (struct sockaddr *)&msg->msg_local,
+		    msg->msg_locallen) == -1) {
+			log_warn("%s: sendtofrom", __func__);
 			sa_free(env, sa);
 			return;
 		}
diff --git a/sbin/iked/util.c b/sbin/iked/util.c
index bb6ae62fd4f..be2c46ba9d9 100644
--- a/sbin/iked/util.c
+++ b/sbin/iked/util.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: util.c,v 1.30 2015/11/23 19:28:34 reyk Exp $	*/
+/*	$OpenBSD: util.c,v 1.31 2016/09/04 10:26:02 vgross Exp $	*/
 
 /*
  * Copyright (c) 2010-2013 Reyk Floeter <reyk@openbsd.org>
@@ -287,6 +287,58 @@ sockaddr_cmp(struct sockaddr *a, struct sockaddr *b, int prefixlen)
 }
 
 ssize_t
+sendtofrom(int s, void *buf, size_t len, int flags, struct sockaddr *to,
+    socklen_t tolen, struct sockaddr *from, socklen_t fromlen)
+{
+	struct iovec		 iov;
+	struct msghdr		 msg;
+	struct cmsghdr		*cmsg;
+	struct in6_pktinfo	*pkt6;
+	struct sockaddr_in	*in;
+	struct sockaddr_in6	*in6;
+	union {
+		struct cmsghdr	hdr;
+		char		inbuf[CMSG_SPACE(sizeof(struct in_addr))];
+		char		in6buf[CMSG_SPACE(sizeof(struct in6_pktinfo))];
+	} cmsgbuf;
+
+	bzero(&msg, sizeof(msg));
+	bzero(&cmsgbuf, sizeof(cmsgbuf));
+
+	iov.iov_base = buf;
+	iov.iov_len = len;
+	msg.msg_iov = &iov;
+	msg.msg_iovlen = 1;
+	msg.msg_name = to;
+	msg.msg_namelen = tolen;
+	msg.msg_control = &cmsgbuf;
+	msg.msg_controllen = sizeof(cmsgbuf);
+
+	cmsg = CMSG_FIRSTHDR(&msg);
+	switch (to->sa_family) {
+	case AF_INET:
+		msg.msg_controllen = sizeof(cmsgbuf.inbuf);
+		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_addr));
+		cmsg->cmsg_level = IPPROTO_IP;
+		cmsg->cmsg_type = IP_SENDSRCADDR;
+		in = (struct sockaddr_in *)from;
+		memcpy(CMSG_DATA(cmsg), &in->sin_addr, sizeof(struct in_addr));
+		break;
+	case AF_INET6:
+		msg.msg_controllen = sizeof(cmsgbuf.in6buf);
+		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
+		cmsg->cmsg_level = IPPROTO_IPV6;
+		cmsg->cmsg_type = IPV6_PKTINFO;
+		in6 = (struct sockaddr_in6 *)from;
+		pkt6 = (struct in6_pktinfo *)CMSG_DATA(cmsg);
+		pkt6->ipi6_addr = in6->sin6_addr;
+		break;
+	}
+
+	return sendmsg(s, &msg, flags);
+}
+
+ssize_t
 recvfromto(int s, void *buf, size_t len, int flags, struct sockaddr *from,
     socklen_t *fromlen, struct sockaddr *to, socklen_t *tolen)
 {