Update to handle arbitrary-length interface descriptions on FreeBSD.

[libpcap] / inet.c

diff --git a/inet.c b/inet.c
index 494de09ea1ea94ad44d2b2b57035161c400ea759..0b16a659072ddc133827f5f5e9885f694b61aaf7 100644 (file)
--- a/inet.c
+++ b/inet.c
@@ -417,10 +417,9 @@ add_addr_to_iflist(pcap_if_t **alldevs, const char *name, u_int flags,
        int s;
        struct ifreq ifrdesc;
 #ifndef IFDESCRSIZE
-#define _IFDESCRSIZE 64
-       char ifdescr[_IFDESCRSIZE];
-#else /* IFDESCRSIZE */
-       char ifdescr[IFDESCRSIZE];
+       size_t descrlen = 64;
+#else
+       size_t descrlen = IFDESCRSIZE;
 #endif /* IFDESCRSIZE */
 #endif /* SIOCGIFDESCR */
 
@@ -430,28 +429,45 @@ add_addr_to_iflist(pcap_if_t **alldevs, const char *name, u_int flags,
         */
        memset(&ifrdesc, 0, sizeof ifrdesc);
        strlcpy(ifrdesc.ifr_name, name, sizeof ifrdesc.ifr_name);
+       s = socket(AF_INET, SOCK_DGRAM, 0);
+       if (s >= 0) {
+               for (;;) {
+                       free(description);
+                       if ((description = malloc(descrlen)) != NULL) {
 #ifdef __FreeBSD__
-       ifrdesc.ifr_buffer.buffer = ifdescr;
-       ifrdesc.ifr_buffer.length = sizeof(ifdescr);
+                               ifrdesc.ifr_buffer.buffer = description;
+                               ifrdesc.ifr_buffer.length = descrlen;
 #else /* __FreeBSD__ */
-       ifrdesc.ifr_data = (caddr_t)ifdescr;
+                               ifrdesc.ifr_data = (caddr_t)description;
 #endif /* __FreeBSD__ */
-       s = socket(AF_INET, SOCK_DGRAM, 0);
-       if (s >= 0) {
-               if (ioctl(s, SIOCGIFDESCR, &ifrdesc) == 0 &&
-                   strlen(ifdescr) != 0)
-                       description = ifdescr;
+                               if (ioctl(s, SIOCGIFDESCR, &ifrdesc) == 0)
+                                       break;
+#ifdef __FreeBSD__
+                               else if (errno == ENAMETOOLONG)
+                                       descrlen = ifrdesc.ifr_buffer.length;
+#endif /* __FreeBSD__ */
+                               else
+                                       break;
+                       } else
+                               break;
+               }
                close(s);
+               if (description != NULL && strlen(description) == 0) {
+                       free(description);
+                       description = NULL;
+               }
        }
 #endif /* SIOCGIFDESCR */
 
        if (add_or_find_if(&curdev, alldevs, name, flags, description,
            errbuf) == -1) {
+               free(description);
                /*
                 * Error - give up.
                 */
                return (-1);
        }
+       free(description);
        if (curdev == NULL) {
                /*
                 * Device wasn't added because it can't be opened.