domain-set: support punycode.

src/Makefile

@@ -15,8 +15,8 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 BIN=smartdns 
-OBJS_LIB=lib/rbtree.o lib/art.o lib/bitops.o lib/radix.o lib/timer_wheel.o
-OBJS_MAIN=smartdns.o fast_ping.o dns_client.o dns_server.o dns.o util.o tlog.o dns_conf.o dns_cache.o http_parse.o proxy.o timer.o lib/conf.o lib/nftset.o
+OBJS_LIB=lib/rbtree.o lib/art.o lib/bitops.o lib/radix.o lib/timer_wheel.o lib/idna.o lib/conf.o lib/nftset.o
+OBJS_MAIN=smartdns.o fast_ping.o dns_client.o dns_server.o dns.o util.o tlog.o dns_conf.o dns_cache.o http_parse.o proxy.o timer.o
 OBJS=$(OBJS_MAIN) $(OBJS_LIB)
 
 # cflags

src/dns_conf.c

@@ -17,6 +17,7 @@
  */
 
 #include "dns_conf.h"
+#include "idna.h"
 #include "list.h"
 #include "rbtree.h"
 #include "tlog.h"
@@ -308,8 +309,14 @@ static int _get_domain(char *value, char *domain, int max_domain_size, char **pt
 		goto errout;
 	}
 
-	memcpy(domain, begin, len);
-	domain[len] = '\0';
+	size_t domain_len = max_domain_size;
+	domain_len = utf8_to_punycode(begin, len, domain, domain_len);
+	if (domain_len <= 0) {
+		tlog(TLOG_ERROR, "domain name %s invalid", value);
+		goto errout;
+	}
+
+	domain[domain_len] = '\0';
 
 	if (ptr_after_domain) {
 		*ptr_after_domain = end + 1;

src/include/idna.h

@@ -0,0 +1,32 @@
+/*************************************************************************
+ *
+ * Copyright (C) 2018-2023 Ruilin Peng (Nick) <[email protected]>.
+ *
+ * smartdns is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * smartdns is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _SMARTDNS_IDNA_H
+#define _SMARTDNS_IDNA_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int utf8_to_punycode(const char *src, int src_len, char *dst, int dst_len);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // !_SMARTDNS_IDNA_H