[Minor] Allow to skip IDN checks in rdns

contrib/librdns/dns_private.h

@@ -151,6 +151,7 @@ struct rdns_resolver {
 	bool async_binded;
 	bool initialized;
 	bool enable_dnssec;
+	int flags;
 	ref_entry_t ref;
 };
 

contrib/librdns/packet.c

@@ -105,21 +105,25 @@ rdns_format_dns_name (struct rdns_resolver *resolver, const char *in,
 	}
 
 	/* Check for non-ascii characters */
-	while (p != end) {
-		if (*p >= 0x80) {
-			need_encode = true;
-		}
-		else if (*p == '.') {
-			labels ++;
+	if (!(resolver->flags & RDNS_RESOLVER_NOIDN)) {
+		while (p != end) {
+			if (*p >= 0x80) {
+				need_encode = true;
+			}
+			else if (*p == '.') {
+				labels++;
+			}
+			p++;
 		}
-		p ++;
 	}
 
 	if (!need_encode) {
 		*out = malloc (inlen + 1);
+
 		if (*out == NULL) {
 			return false;
 		}
+
 		o = *out;
 		memcpy (o, in, inlen);
 		o[inlen] = '\0';

contrib/librdns/rdns.h

@@ -233,10 +233,15 @@ struct rdns_request_name {
  * RDNS API
  */
 
+enum rdns_resolver_flags {
+	RDNS_RESOLVER_DEFAULT,
+	RDNS_RESOLVER_NOIDN = (1u << 0u),
+};
+
 /**
  * Create DNS resolver structure
  */
-struct rdns_resolver *rdns_resolver_new (void);
+struct rdns_resolver *rdns_resolver_new (int flags);
 
 /**
  * Bind resolver to specified async context

contrib/librdns/resolver.c

@@ -1049,18 +1049,19 @@ rdns_resolver_free (struct rdns_resolver *resolver)
 
 
 struct rdns_resolver *
-rdns_resolver_new (void)
+rdns_resolver_new (int flags)
 {
-	struct rdns_resolver     *new;
+	struct rdns_resolver     *new_resolver;
 
-	new = calloc (1, sizeof (struct rdns_resolver));
+	new_resolver = calloc (1, sizeof (struct rdns_resolver));
 
-	REF_INIT_RETAIN (new, rdns_resolver_free);
+	REF_INIT_RETAIN (new_resolver, rdns_resolver_free);
 
-	new->logger = rdns_logger_internal;
-	new->log_data = new;
+	new_resolver->logger = rdns_logger_internal;
+	new_resolver->log_data = new_resolver;
+	new_resolver->flags = flags;
 
-	return new;
+	return new_resolver;
 }
 
 void

src/libserver/dns.c

@@ -884,7 +884,8 @@ rspamd_dns_resolver_init (rspamd_logger_t *logger,
 		dns_resolver->max_retransmits = 2;
 	}
 
-	dns_resolver->r = rdns_resolver_new ();
+	/* IDN translation is performed in Rspamd now */
+	dns_resolver->r = rdns_resolver_new (RDNS_RESOLVER_NOIDN);
 
 	UErrorCode uc_err = U_ZERO_ERROR;