- The IO system now tracks all local IP addresses, so that the DHCP

  applications (particularly the dhcrelay) can discern between what frames
  were tranmsitted to it, and what frames are being carried through it which
  it should not intercept. [ISC-Bugs #15573]

2 files changed, 104 insertions, 47 deletions

diff --git a/relay/dhcrelay.8 b/relay/dhcrelay.8
index 05b6dabc..1e0a9a9c 100644
--- a/relay/dhcrelay.8
+++ b/relay/dhcrelay.8
@@ -27,7 +27,7 @@
 .\" see ``http://www.isc.org/isc''.  To learn more about Vixie
 .\" Enterprises, see ``http://www.vix.com''.
 .\"
-.\" $Id: dhcrelay.8,v 1.10 2005/03/17 20:15:24 dhankins Exp $
+.\" $Id: dhcrelay.8,v 1.11 2006/02/27 23:56:13 dhankins Exp $
 .\"
 .TH dhcrelay 8
 .SH NAME
@@ -48,6 +48,11 @@ dhcrelay - Dynamic Host Configuration Protocol Relay Agent
 .B -i
 .I if0
 [
+.B -is
+.I server
+...
+]
+[
 .B ...
 .B -i
 .I ifN
@@ -114,6 +119,11 @@ server) is attached.   However, in some cases it may be necessary to
 exclude some networks; in this case, you must list all those network
 interfaces that should \fInot\fR be excluded using the \fB-i\fR flag.
 .PP
+The
+.B -is
+flag can be used to indicate that for the previous interface specified with
+-i, packets should be forwarded to the specified server.
+.PP
 In some cases it
 .I is
 helpful for the relay agent to forward requests from networks on which
diff --git a/relay/dhcrelay.c b/relay/dhcrelay.c
index 452724b1..4abc5250 100644
--- a/relay/dhcrelay.c
+++ b/relay/dhcrelay.c
@@ -34,7 +34,7 @@
 
 #ifndef lint
 static char ocopyright[] =
-"$Id: dhcrelay.c,v 1.54 2006/02/24 23:16:30 dhankins Exp $ Copyright (c) 2004-2006 Internet Systems Consortium.  All rights reserved.\n";
+"$Id: dhcrelay.c,v 1.55 2006/02/27 23:56:13 dhankins Exp $ Copyright (c) 2004-2006 Internet Systems Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -92,11 +92,6 @@ enum { forward_and_append,	/* Forward and append our own relay option. */
 u_int16_t local_port;
 u_int16_t remote_port;
 
-struct server_list {
-	struct server_list *next;
-	struct sockaddr_in to;
-} *servers;
-
 static char copyright [] = "Copyright 2004-2005 Internet Systems Consortium.";
 static char arr [] = "All rights reserved.";
 static char message [] = "Internet Systems Consortium DHCP Relay Agent";
@@ -113,6 +108,7 @@ int main (argc, argv, envp)
 	int quiet = 0;
 	isc_result_t status;
 	char *s;
+	struct interface_info *tmp = (struct interface_info *)0;
 
 	/* Make sure we have stdin, stdout and stderr. */
 	i = open ("/dev/null", O_RDWR);
@@ -154,8 +150,8 @@ int main (argc, argv, envp)
 		} else if (!strcmp (argv [i], "-d")) {
 			no_daemon = 1;
  		} else if (!strcmp (argv [i], "-i")) {
-			struct interface_info *tmp =
-				(struct interface_info *)0;
+			if (tmp)
+				interface_dereference (&tmp, MDL);
 			status = interface_allocate (&tmp, MDL);
 			if (status != ISC_R_SUCCESS)
 				log_fatal ("%s: interface_allocate: %s",
@@ -166,7 +162,14 @@ int main (argc, argv, envp)
 			}
 			strcpy (tmp -> name, argv [i]);
 			interface_snorf (tmp, INTERFACE_REQUESTED);
-			interface_dereference (&tmp, MDL);
+ 		} else if (!strcmp (argv [i], "-is")) {
+			if (++i == argc)
+				usage ();
+			if (!tmp) {
+				log_error ("-is must follow -i.");
+				usage ();
+			}
+			new_relay_server (argv [i], &tmp -> servers);
 		} else if (!strcmp (argv [i], "-q")) {
 			quiet = 1;
 			quiet_interface_discovery = 1;
@@ -206,33 +209,15 @@ int main (argc, argv, envp)
 			log_info ("isc-dhcrelay-%s", DHCP_VERSION);
 			exit (0);
  		} else {
-			struct hostent *he;
-			struct in_addr ia, *iap = (struct in_addr *)0;
-			if (inet_aton (argv [i], &ia)) {
-				iap = &ia;
-			} else {
-				he = gethostbyname (argv [i]);
-				if (!he) {
-					log_error ("%s: host unknown",
-						   argv [i]);
-				} else {
-					iap = ((struct in_addr *)
-					       he -> h_addr_list [0]);
-				}
-			}
-			if (iap) {
-				sp = ((struct server_list *)
-				      dmalloc (sizeof *sp, MDL));
-				if (!sp)
-					log_fatal ("no memory for server.\n");
-				sp -> next = servers;
-				servers = sp;
-				memcpy (&sp -> to.sin_addr,
-					iap, sizeof *iap);
-			}
+			new_relay_server (argv [i], &servers);
  		}
 	}
 
+	limited_broadcast.s_addr = INADDR_BROADCAST;
+
+	if (tmp)
+		interface_dereference (&tmp, MDL);
+
 	if ((s = getenv ("PATH_DHCRELAY_PID"))) {
 		path_dhcrelay_pid = s;
 	}
@@ -259,7 +244,7 @@ int main (argc, argv, envp)
 	remote_port = htons (ntohs (local_port) + 1);
   
 	/* We need at least one server. */
-	if (!sp) {
+	if (!servers) {
 		usage ();
 	}
 
@@ -272,6 +257,29 @@ int main (argc, argv, envp)
 #endif
 	}
 
+	if (interfaces) {
+		interface_reference (&tmp, interfaces, MDL);
+		do {
+			struct interface_info *next = NULL;
+			if (tmp -> next)
+				interface_reference (&next, tmp -> next, MDL);
+		
+			for (sp = tmp -> servers; sp; sp = sp -> next) {
+				sp -> to.sin_port = local_port;
+				sp -> to.sin_family = AF_INET;
+#ifdef HAVE_SA_LEN
+				sp -> to.sin_len = sizeof sp -> to;
+#endif
+			}
+
+			interface_dereference (&tmp, MDL);
+			if (next) {
+				interface_reference (&tmp, next, MDL);
+				interface_dereference (&next, MDL);
+			}
+		} while (tmp);
+	}
+
 	/* Get the current time... */
 	GET_TIME (&cur_time);
 
@@ -323,6 +331,36 @@ int main (argc, argv, envp)
 	return 0;
 }
 
+void new_relay_server (char *arg, struct server_list **servers)
+{
+	struct hostent *he;
+	struct in_addr ia, *iap = (struct in_addr *)0;
+	struct server_list *sp;
+
+	if (inet_aton (arg, &ia)) {
+		iap = &ia;
+	} else {
+		he = gethostbyname (arg);
+		if (!he) {
+			log_error ("%s: host unknown", arg);
+		} else {
+			iap = ((struct in_addr *)
+			       he -> h_addr_list [0]);
+		}
+	}
+	if (iap) {
+		sp = ((struct server_list *)
+		      dmalloc (sizeof *sp, MDL));
+		if (!sp)
+			log_fatal ("no memory for server.\n");
+		memset(sp, 0, sizeof *sp);
+		sp -> next = *servers;
+		*servers = sp;
+		memcpy (&sp -> to.sin_addr,
+			iap, sizeof *iap);
+	}
+}
+
 void relay (ip, packet, length, from_port, from, hfrom)
 	struct interface_info *ip;
 	struct dhcp_packet *packet;
@@ -335,6 +373,7 @@ void relay (ip, packet, length, from_port, from, hfrom)
 	struct sockaddr_in to;
 	struct interface_info *out;
 	struct hardware hto, *htop;
+	int i;
 
 	if (packet -> hlen > sizeof packet -> chaddr) {
 		log_info ("Discarding packet with invalid hlen.");
@@ -345,14 +384,16 @@ void relay (ip, packet, length, from_port, from, hfrom)
 	   in the packet. */
 	if (packet -> giaddr.s_addr) {
 		for (out = interfaces; out; out = out -> next) {
-			if (!memcmp (&out -> primary_address,
-				     &packet -> giaddr,
-				     sizeof packet -> giaddr))
-				break;
+			for (i = 0; i < out -> address_count; i++) {
+				if (out -> addresses [i].s_addr ==
+				    packet -> giaddr.s_addr)
+					goto matched;
+			}
 		}
 	} else {
 		out = (struct interface_info *)0;
 	}
+      matched:
 
 	/* If it's a bootreply, forward it to the client. */
 	if (packet -> op == BOOTREPLY) {
@@ -388,15 +429,18 @@ void relay (ip, packet, length, from_port, from, hfrom)
 			return;
 
 		if (!out) {
-			log_error ("packet to bogus giaddr %s.\n",
+			log_error ("packet to bogus giaddr %s.",
 			      inet_ntoa (packet -> giaddr));
 			++bogus_giaddr_drops;
 			return;
 		}
 
+		if (out -> address_count < 1)
+			log_fatal ("no IP address on interface %s!",
+				   out -> name);
 		if (send_packet (out,
 				 (struct packet *)0,
-				 packet, length, out -> primary_address,
+				 packet, length, out -> addresses [0],
 				 &to, htop) < 0) {
 			++server_packet_errors;
 		} else {
@@ -415,10 +459,13 @@ void relay (ip, packet, length, from_port, from, hfrom)
 	if (out)
 		return;
 
+	if (ip -> address_count < 1)
+		log_fatal ("no IP address on interface %s", ip -> name);
+
 	/* Add relay agent options if indicated.   If something goes wrong,
 	   drop the packet. */
 	if (!(length = add_relay_agent_options (ip, packet, length,
-						ip -> primary_address)))
+						ip -> addresses [0])))
 		return;
 
 	/* If giaddr is not already set, Set it so the server can
@@ -427,7 +474,7 @@ void relay (ip, packet, length, from_port, from, hfrom)
 	   set, the response will be sent directly to the relay agent
 	   that set giaddr, so we won't see it. */
 	if (!packet -> giaddr.s_addr)
-		packet -> giaddr = ip -> primary_address;
+		packet -> giaddr = ip -> addresses [0];
 	if (packet -> hops < max_hop_count)
 		packet -> hops = packet -> hops + 1;
 	else
@@ -435,11 +482,12 @@ void relay (ip, packet, length, from_port, from, hfrom)
 
 	/* Otherwise, it's a BOOTREQUEST, so forward it to all the
 	   servers. */
-	for (sp = servers; sp; sp = sp -> next) {
+	for (sp = (ip -> servers
+		   ? ip -> servers : servers); sp; sp = sp -> next) {
 		if (send_packet ((fallback_interface
 				  ? fallback_interface : interfaces),
 				 (struct packet *)0,
-				 packet, length, ip -> primary_address,
+				 packet, length, ip -> addresses [0],
 				 &sp -> to, (struct hardware *)0) < 0) {
 			++client_packet_errors;
 		} else {
@@ -450,13 +498,12 @@ void relay (ip, packet, length, from_port, from, hfrom)
 			++client_packets_relayed;
 		}
 	}
-				 
 }
 
 static void usage ()
 {
 	log_fatal ("Usage: dhcrelay [-p <port>] [-d] [-D] [-i %s%s%s%s",
-		"interface] [-q] [-a]\n                ",
+		"interface [-is server ... ]]\n                ",
 		"[-c count] [-A length] ",
 		"[-m append|replace|forward|discard]\n",
 		"                [server1 [... serverN]]");