prevent bogus reverse query for 1.0.0.0.in-addr.arpa.

this occurs by mixing up ::1 as IPv6 auto-tunnel address like ::10.1.1.1.

1 files changed, 5 insertions, 7 deletions

diff --git a/src/lib/libc/net/gethostnamadr.c b/src/lib/libc/net/gethostnamadr.c
index 64be28a351..13a8eef846 100644
--- a/src/lib/libc/net/gethostnamadr.c
+++ b/src/lib/libc/net/gethostnamadr.c
@@ -52,7 +52,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: gethostnamadr.c,v 1.38 1999/12/11 08:32:20 itojun Exp $";
+static char rcsid[] = "$OpenBSD: gethostnamadr.c,v 1.39 1999/12/11 08:40:17 itojun Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/param.h>
@@ -664,8 +664,6 @@ gethostbyaddr(addr, len, af)
         int len, af;
 {
         const u_char *uaddr = (const u_char *)addr;
-        static const u_char mapped[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0xff,0xff };
-        static const u_char tunnelled[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0,0 };
         int n, size, i;
         querybuf buf;
         register struct hostent *hp;
@@ -682,11 +680,11 @@ gethostbyaddr(addr, len, af)
         }
 
         if (af == AF_INET6 && len == IN6ADDRSZ &&
-            (!bcmp(uaddr, mapped, sizeof mapped) ||
-             !bcmp(uaddr, tunnelled, sizeof tunnelled))) {
+            (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)uaddr) ||
+             IN6_IS_ADDR_V4COMPAT((struct in6_addr *)uaddr))) {
                 /* Unmap. */
-                addr += sizeof mapped;
-                uaddr += sizeof mapped;
+                addr += IN6ADDRSZ - INADDRSZ;
+                uaddr += IN6ADDRSZ - INADDRSZ;
                 af = AF_INET;
                 len = INADDRSZ;
         }