New expansion operator: reverse_ip

3 files changed, 30 insertions, 6 deletions

diff --git a/src/src/expand.c b/src/src/expand.c
index 6e47125bb..e5daff1a8 100644
--- a/src/src/expand.c
+++ b/src/src/expand.c
@@ -1,4 +1,4 @@
-/* $Cambridge: exim/src/src/expand.c,v 1.105 2009/11/16 19:50:36 nm4 Exp $ */
+/* $Cambridge: exim/src/src/expand.c,v 1.106 2010/06/05 23:50:18 pdp Exp $ */
 
 /*************************************************
 *     Exim - an Internet mail transport agent    *
@@ -156,6 +156,7 @@ static uschar *op_table_underscore[] = {
   US"from_utf8",
   US"local_part",
   US"quote_local_part",
+  US"reverse_ip",
   US"time_eval",
   US"time_interval"};
 
@@ -163,6 +164,7 @@ enum {
   EOP_FROM_UTF8,
   EOP_LOCAL_PART,
   EOP_QUOTE_LOCAL_PART,
+  EOP_REVERSE_IP,
   EOP_TIME_EVAL,
   EOP_TIME_INTERVAL };
 
@@ -5790,6 +5792,25 @@ while (*s != 0)
         continue;
         }
 
+      /* Reverse IP, including IPv6 to dotted-nibble */
+
+      case EOP_REVERSE_IP:
+        {
+        int family, maskptr;
+        uschar reversed[128];
+
+        family = string_is_ip_address(sub, &maskptr);
+        if (family == 0)
+          {
+          expand_string_message = string_sprintf(
+              "reverse_ip() not given an IP address [%s]", sub);
+          goto EXPAND_FAILED;
+          }
+        invert_address(reversed, sub);
+        yield = string_cat(yield, &size, &ptr, reversed, Ustrlen(reversed));
+        continue;
+        }
+
       /* Unknown operator */
 
       default:
diff --git a/src/src/functions.h b/src/src/functions.h
index 436038735..00f8bb7ba 100644
--- a/src/src/functions.h
+++ b/src/src/functions.h
@@ -1,4 +1,4 @@
-/* $Cambridge: exim/src/src/functions.h,v 1.49 2010/06/05 11:13:30 pdp Exp $ */
+/* $Cambridge: exim/src/src/functions.h,v 1.50 2010/06/05 23:50:18 pdp Exp $ */
 
 /*************************************************
 *     Exim - an Internet mail transport agent    *
@@ -141,6 +141,7 @@ extern int     host_nmtoa(int, int *, int, uschar *, int);
 extern uschar *host_ntoa(int, const void *, uschar *, int *);
 extern int     host_scan_for_local_hosts(host_item *, host_item **, BOOL *);
 
+extern void    invert_address(uschar *, uschar *);
 extern int     ip_bind(int, int, uschar *, int);
 extern int     ip_connect(int, int, uschar *, int, int);
 extern void    ip_keepalive(int, uschar *, BOOL);
diff --git a/src/src/verify.c b/src/src/verify.c
index cc821a201..371883a37 100644
--- a/src/src/verify.c
+++ b/src/src/verify.c
@@ -1,4 +1,4 @@
-/* $Cambridge: exim/src/src/verify.c,v 1.54 2009/11/16 19:50:37 nm4 Exp $ */
+/* $Cambridge: exim/src/src/verify.c,v 1.55 2010/06/05 23:50:18 pdp Exp $ */
 
 /*************************************************
 *     Exim - an Internet mail transport agent    *
@@ -2513,16 +2513,18 @@ return verify_check_this_host(listptr, sender_host_cache, NULL,
 
 
 /*************************************************
-*    Invert an IP address for a DNS black list   *
+*              Invert an IP address              *
 *************************************************/
 
-/*
+/* Originally just used for DNS xBL lists, now also used for the
+reverse_ip expansion operator.
+
 Arguments:
   buffer         where to put the answer
   address        the address to invert
 */
 
-static void
+void
 invert_address(uschar *buffer, uschar *address)
 {
 int bin[4];