handle SIOCGIFCONF for as many interfaces as provided

1 files changed, 44 insertions, 23 deletions

diff --git a/lib/libc/rpc/pmap_rmt.c b/lib/libc/rpc/pmap_rmt.c
index 976721e56be..6afb09ada5f 100644
--- a/lib/libc/rpc/pmap_rmt.c
+++ b/lib/libc/rpc/pmap_rmt.c
@@ -28,7 +28,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char *rcsid = "$OpenBSD: pmap_rmt.c,v 1.13 1997/01/02 09:21:07 deraadt Exp $";
+static char *rcsid = "$OpenBSD: pmap_rmt.c,v 1.14 1997/01/22 18:50:41 deraadt Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 /*
@@ -162,37 +162,54 @@ xdr_rmtcallres(xdrs, crp)
  */
 
 static int
-getbroadcastnets(addrs, sock, buf)
-	struct in_addr *addrs;
+newgetbroadcastnets(addrsp, sock)
+	struct in_addr **addrsp;
 	int sock;  /* any valid socket will do */
-	char *buf;  /* why allocxate more when we can use existing... */
 {
+	char *inbuf = NULL;
 	struct ifconf ifc;
-        struct ifreq ifreq, *ifr;
+	struct ifreq ifreq, *ifr;
 	struct sockaddr_in *sin;
-        char *cp, *cplim;
-        int i = 0;
+	char *cp, *cplim;
+	int inbuflen = 256;
+	struct in_addr *addrs;
+	int i = 0;
+
+	while (1) {
+		ifc.ifc_len = inbuflen;
+		ifc.ifc_buf = inbuf = realloc(inbuf, inbuflen);
+		if (inbuf == NULL)
+			return (0);
+		if (ioctl(sock, SIOCGIFCONF, (char *)&ifc) < 0) {
+			perror("broadcast: ioctl (get interface configuration)");
+			free(inbuf);
+			return (0);
+		}
+		if (ifc.ifc_len + sizeof(ifreq) < inbuflen)
+			break;
+		inbuflen *= 2;
+	}
+	addrs = (struct in_addr *)malloc((inbuflen / sizeof *sin) * sizeof sin);
+	if (addrs == NULL) {
+		*addrsp = NULL;
+		free(inbuf);
+		return (0);
+	}
 
-        ifc.ifc_len = UDPMSGSIZE;
-        ifc.ifc_buf = buf;
-        if (ioctl(sock, SIOCGIFCONF, (char *)&ifc) < 0) {
-                perror("broadcast: ioctl (get interface configuration)");
-                return (0);
-        }
 #define max(a, b) (a > b ? a : b)
 #define size(p)	max((p).sa_len, sizeof(p))
-	cplim = buf + ifc.ifc_len; /*skip over if's with big ifr_addr's */
-	for (cp = buf; cp < cplim;
+	cplim = inbuf + ifc.ifc_len; /*skip over if's with big ifr_addr's */
+	for (cp = inbuf; cp < cplim;
 	    cp += sizeof (ifr->ifr_name) + size(ifr->ifr_addr)) {
 		ifr = (struct ifreq *)cp;
 		if (ifr->ifr_addr.sa_family != AF_INET)
 			continue;
 		ifreq = *ifr;
-                if (ioctl(sock, SIOCGIFFLAGS, (char *)&ifreq) < 0) {
-                        perror("broadcast: ioctl (get interface flags)");
-                        continue;
-                }
-                if ((ifreq.ifr_flags & IFF_BROADCAST) &&
+		if (ioctl(sock, SIOCGIFFLAGS, (char *)&ifreq) < 0) {
+			perror("broadcast: ioctl (get interface flags)");
+			continue;
+		}
+		if ((ifreq.ifr_flags & IFF_BROADCAST) &&
 		    (ifreq.ifr_flags & IFF_UP)) {
 			sin = (struct sockaddr_in *)&ifr->ifr_addr;
 			if (ioctl(sock, SIOCGIFBRDADDR, (char *)&ifreq) < 0) {
@@ -205,6 +222,8 @@ getbroadcastnets(addrs, sock, buf)
 			}
 		}
 	}
+	free(inbuf);
+	*addrsp = addrs;
 	return (i);
 }
 
@@ -233,7 +252,7 @@ clnt_broadcast(prog, vers, proc, xargs, argsp, xresults, resultsp, eachresult)
 	bool_t done = FALSE;
 	register u_long xid;
 	u_long port;
-	struct in_addr addrs[20];
+	struct in_addr *addrs;
 	struct sockaddr_in baddr, raddr; /* broadcast and response addresses */
 	struct rmtcallargs a;
 	struct rmtcallres r;
@@ -271,7 +290,7 @@ clnt_broadcast(prog, vers, proc, xargs, argsp, xresults, resultsp, eachresult)
 		FD_ZERO(fds);
 	}
 
-	nets = getbroadcastnets(addrs, sock, inbuf);
+	nets = newgetbroadcastnets(&addrs, sock);
 	memset(&baddr, 0, sizeof (baddr));
 	baddr.sin_len = sizeof(struct sockaddr_in);
 	baddr.sin_family = AF_INET;
@@ -331,7 +350,7 @@ clnt_broadcast(prog, vers, proc, xargs, argsp, xresults, resultsp, eachresult)
 	recv_again:
 		msg.acpted_rply.ar_verf = _null_auth;
 		msg.acpted_rply.ar_results.where = (caddr_t)&r;
-                msg.acpted_rply.ar_results.proc = xdr_rmtcallres;
+		msg.acpted_rply.ar_results.proc = xdr_rmtcallres;
 
 		/* XXX we know the other bits are still clear */
 		FD_SET(sock, fds);
@@ -386,6 +405,8 @@ clnt_broadcast(prog, vers, proc, xargs, argsp, xresults, resultsp, eachresult)
 		}
 	}
 done_broad:
+	if (addrs)
+		free(addrs);
 	if (fds != &readfds)
 		free(fds);
 	if (sock >= 0)