When you have multiple addresses on the same network on different

interfaces (such as when you are part of a carp pool), and you run
rpcbind -h to restrict which interfaces have rpc services, rpcbind can
none-the-less return addresses that aren't in the -h list.  This patch
enforces the rule that when you specify -h on the command line, then
services returned from rpcbind must be to one of the addresses listed
in -h, or be a loopback address (since localhost is implicit when
running -h).

The root cause of this is the assumption in addrmerge that there can
be only one interface that matches a given network IP address.  This
turns out not to be the case.  To retain historical behavior, I didn't
try to fix the routine to prefer the address that the request came
into, since I didn't know the side effects that might cause in the
normal case.  My quick analysis suggests that it wouldn't be a
problem, but since this code is tricky I opted for the more
conservative patch of only restricting the reply when -h is in effect.

Hence, this change will have no effect when you are running rpcbind
without -h.

Reviewed by:	alfred@
Sponsored by:	iX Systems
MFC after:	2 weeks

1 files changed, 10 insertions, 10 deletions

diff --git a/usr.sbin/rpcbind/util.c b/usr.sbin/rpcbind/util.c
index 66797a7..9cdfa70 100644
--- a/usr.sbin/rpcbind/util.c
+++ b/usr.sbin/rpcbind/util.c
@@ -58,13 +58,6 @@
 
 #include "rpcbind.h"
 
-#define	SA2SIN(sa)	((struct sockaddr_in *)(sa))
-#define	SA2SINADDR(sa)	(SA2SIN(sa)->sin_addr)
-#ifdef INET6
-#define	SA2SIN6(sa)	((struct sockaddr_in6 *)(sa))
-#define	SA2SIN6ADDR(sa)	(SA2SIN6(sa)->sin6_addr)
-#endif
-
 static struct sockaddr_in *local_in4;
 #ifdef INET6
 static struct sockaddr_in6 *local_in6;
@@ -176,9 +169,13 @@ addrmerge(struct netbuf *caller, char *serv_uaddr, char *clnt_uaddr,
 		goto freeit;
 
 	/*
-	 * Loop through all interfaces. For each interface, see if the
-	 * network portion of its address is equal to that of the client.
-	 * If so, we have found the interface that we want to use.
+	 * Loop through all interfaces. For each interface, see if it
+	 * is either the loopback interface (which we always listen
+	 * on) or is one of the addresses the program bound to (the
+	 * wildcard by default, or a subset if -h is specified) and
+	 * the network portion of its address is equal to that of the
+	 * client.  If so, we have found the interface that we want to
+	 * use.
 	 */
 	bestif = NULL;
 	for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) {
@@ -189,6 +186,9 @@ addrmerge(struct netbuf *caller, char *serv_uaddr, char *clnt_uaddr,
 		    !(ifap->ifa_flags & IFF_UP))
 			continue;
 
+		if (!(ifap->ifa_flags & IFF_LOOPBACK) && !listen_addr(ifsa))
+			continue;
+
 		switch (hint_sa->sa_family) {
 		case AF_INET:
 			/*