Update code, fix PTR issue

dns.c

@@ -758,6 +758,8 @@ int _dns_encode_CNAME(struct dns_context *context, struct dns_rrs *rrs)
 		return -1;
 	}
 
+	/* when code domain, len must plus 1, because of length at the begining */
+	rr_len++;
 	if (rr_len > rrs->len) {
 		return -1;
 	}

dns_server.c

@@ -486,7 +486,7 @@ static int _dns_server_process_ptr(struct dns_request *request, struct dns_packe
 		default:
 			break;
 		}
-		if (strncmp(request->domain, reverse_addr, sizeof(reverse_addr)) != 0) {
+		if (strncmp(request->domain, reverse_addr, sizeof(reverse_addr)) == 0) {
 			found = 1;
 			break;
 		}