Add IP_RECVRTABLE socket option to be used with a IPPROTO_IP

level that allows one to retrieve the original routing domain
of UDP datagrams diverted by the pf via "divert-to" with a
recvmsg(2).

ok claudio

4 files changed, 31 insertions, 5 deletions

diff --git a/sys/netinet/in.h b/sys/netinet/in.h
index f204cbb3dc8..979f61ff831 100644
--- a/sys/netinet/in.h
+++ b/sys/netinet/in.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: in.h,v 1.88 2011/05/02 13:48:38 mikeb Exp $	*/
+/*	$OpenBSD: in.h,v 1.89 2011/06/15 09:11:01 mikeb Exp $	*/
 /*	$NetBSD: in.h,v 1.20 1996/02/13 23:41:47 christos Exp $	*/
 
 /*
@@ -281,6 +281,7 @@ struct ip_opts {
 #define IP_MINTTL		32   /* minimum TTL for packet or drop */
 #define IP_RECVDSTPORT		33   /* bool; receive IP dst port w/dgram */
 #define IP_PIPEX		34   /* bool; using PIPEX */
+#define IP_RECVRTABLE		35   /* bool; receive rdomain w/dgram */
 
 #define IP_RTABLE		0x1021	/* int; routing table, see SO_RTABLE */
 
diff --git a/sys/netinet/in_pcb.h b/sys/netinet/in_pcb.h
index b631ec3d4f2..de634b82b7f 100644
--- a/sys/netinet/in_pcb.h
+++ b/sys/netinet/in_pcb.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: in_pcb.h,v 1.70 2010/09/23 04:45:15 yasuoka Exp $	*/
+/*	$OpenBSD: in_pcb.h,v 1.71 2011/06/15 09:11:01 mikeb Exp $	*/
 /*	$NetBSD: in_pcb.h,v 1.14 1996/02/13 23:42:00 christos Exp $	*/
 
 /*
@@ -174,9 +174,11 @@ struct inpcbtable {
 #define	INP_RECVIF	0x080	/* receive incoming interface */
 #define	INP_RECVTTL	0x040	/* receive incoming IP TTL */
 #define	INP_RECVDSTPORT	0x200	/* receive IP dst addr before rdr */
+#define	INP_RECVRTABLE	0x400	/* receive routing table */
 
 #define	INP_CONTROLOPTS	(INP_RECVOPTS|INP_RECVRETOPTS|INP_RECVDSTADDR| \
-	    INP_RXSRCRT|INP_HOPLIMIT|INP_RECVIF|INP_RECVTTL|INP_RECVDSTPORT)
+	    INP_RXSRCRT|INP_HOPLIMIT|INP_RECVIF|INP_RECVTTL|INP_RECVDSTPORT| \
+	    INP_RECVRTABLE)
 
 /*
  * These flags' values should be determined by either the transport
diff --git a/sys/netinet/ip_input.c b/sys/netinet/ip_input.c
index 0d71e404e78..812d650c449 100644
--- a/sys/netinet/ip_input.c
+++ b/sys/netinet/ip_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_input.c,v 1.191 2011/04/19 03:47:29 dlg Exp $	*/
+/*	$OpenBSD: ip_input.c,v 1.192 2011/06/15 09:11:01 mikeb Exp $	*/
 /*	$NetBSD: ip_input.c,v 1.30 1996/03/16 23:53:58 christos Exp $	*/
 
 /*
@@ -1790,5 +1790,20 @@ ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
 		if (*mp)
 			mp = &(*mp)->m_next;
 	}
+	if (inp->inp_flags & INP_RECVRTABLE) {
+		u_int rtableid = inp->inp_rtableid;
+#if NPF > 0
+		struct pf_divert *divert;
+
+		if (m && m->m_pkthdr.pf.flags & PF_TAG_DIVERTED &&
+		    (divert = pf_find_divert(m)) != NULL)
+			rtableid = divert->rdomain;
+#endif
+
+		*mp = sbcreatecontrol((caddr_t) &rtableid,
+		    sizeof(u_int), IP_RECVRTABLE, IPPROTO_IP);
+		if (*mp)
+			mp = &(*mp)->m_next;
+	}
 }
 
diff --git a/sys/netinet/ip_output.c b/sys/netinet/ip_output.c
index de189da7995..d8bdd6ee422 100644
--- a/sys/netinet/ip_output.c
+++ b/sys/netinet/ip_output.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_output.c,v 1.221 2011/05/28 12:51:40 weerd Exp $	*/
+/*	$OpenBSD: ip_output.c,v 1.222 2011/06/15 09:11:01 mikeb Exp $	*/
 /*	$NetBSD: ip_output.c,v 1.28 1996/02/13 23:43:07 christos Exp $	*/
 
 /*
@@ -1068,6 +1068,7 @@ ip_ctloutput(op, so, level, optname, mp)
 		case IP_RECVIF:
 		case IP_RECVTTL:
 		case IP_RECVDSTPORT:
+		case IP_RECVRTABLE:
 			if (m == NULL || m->m_len != sizeof(int))
 				error = EINVAL;
 			else {
@@ -1117,6 +1118,9 @@ ip_ctloutput(op, so, level, optname, mp)
 				case IP_RECVDSTPORT:
 					OPTSET(INP_RECVDSTPORT);
 					break;
+				case IP_RECVRTABLE:
+					OPTSET(INP_RECVRTABLE);
+					break;
 				}
 			}
 			break;
@@ -1448,6 +1452,7 @@ ip_ctloutput(op, so, level, optname, mp)
 		case IP_RECVIF:
 		case IP_RECVTTL:
 		case IP_RECVDSTPORT:
+		case IP_RECVRTABLE:
 			*mp = m = m_get(M_WAIT, MT_SOOPTS);
 			m->m_len = sizeof(int);
 			switch (optname) {
@@ -1486,6 +1491,9 @@ ip_ctloutput(op, so, level, optname, mp)
 			case IP_RECVDSTPORT:
 				optval = OPTBIT(INP_RECVDSTPORT);
 				break;
+			case IP_RECVRTABLE:
+				optval = OPTBIT(INP_RECVRTABLE);
+				break;
 			}
 			*mtod(m, int *) = optval;
 			break;