+ /* 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;
+ }
+