support tcp protocol

Makefile

@@ -20,6 +20,7 @@ LIB_H = dnscrypt.h udp_request.h edns.h logger.h dnscrypt-proxy/src/libevent/inc
 
 LIB_OBJS += dnscrypt.o
 LIB_OBJS += udp_request.o
+LIB_OBJS += tcp_request.o
 LIB_OBJS += edns.o
 LIB_OBJS += logger.o
 LIB_OBJS += main.o

README.md

@@ -11,8 +11,6 @@ This is dnscrypt wrapper (server-side dnscrypt proxy), which helps to add dnscry
 This software is modified from
 [dnscrypt-proxy](https://github.com/opendns/dnscrypt-proxy).
 
-Only udp protocol is supported now, tcp is work in progress.
-
 INSTALLATION
 ============
 

TODO

@@ -1,2 +1,2 @@
-* support tcp protocol
+* reconnect to resolver server?
 * test framework?

compat.h

@@ -37,6 +37,8 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <arpa/inet.h>
+#include <sys/queue.h>
+#include <netinet/tcp.h>
 
 #define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[1]))
 #define COMPILER_ASSERT(X) (void) sizeof(char[(X) ? 1 : -1])

dnscrypt.h

@@ -2,8 +2,10 @@
 #define DNSCRYPT_H
 
 #include "compat.h"
-#include <sys/queue.h>
 #include <event2/event.h>
+#include <event2/listener.h>
+#include <event2/bufferevent.h>
+#include <event2/buffer.h>
 #include <event2/util.h>
 #include <crypto_box.h>
 #include <crypto_stream.h>
@@ -72,6 +74,7 @@
 
 #include "edns.h"
 #include "udp_request.h"
+#include "tcp_request.h"
 #include "rfc1035.h"
 #include "logger.h"
 #include "salsa20_random.h"
@@ -80,6 +83,8 @@
 
 #define DNSCRYPT_QUERY_HEADER_SIZE \
     (DNSCRYPT_MAGIC_HEADER_LEN + crypto_box_PUBLICKEYBYTES + crypto_box_HALF_NONCEBYTES + crypto_box_MACBYTES)
+#define DNSCRYPT_RESPONSE_HEADER_SIZE \
+    (DNSCRYPT_MAGIC_HEADER_LEN + crypto_box_NONCEBYTES + crypto_box_MACBYTES)
 
 #define DNSCRYPT_REPLY_HEADER_SIZE \
     (DNSCRYPT_MAGIC_HEADER_LEN + crypto_box_HALF_NONCEBYTES * 2 + crypto_box_MACBYTES)
@@ -91,6 +96,8 @@ struct context {
      ev_socklen_t resolver_sockaddr_len;
      const char *resolver_address;
      const char *listen_address;
+     struct evconnlistener *tcp_conn_listener;
+     struct event *tcp_accept_timer;
      struct event *udp_listener_event;
      struct event *udp_resolver_event;
      evutil_socket_t udp_listener_handle;
@@ -107,7 +114,6 @@ struct context {
 
      /* Process stuff. */
      bool daemonize;
-     bool tcp_only;
      char *user;
      uid_t user_id;
      gid_t user_group;

main.c

@@ -197,7 +197,6 @@ main(int argc, const char **argv)
         OPT_STRING('r', "resolver-address", &c.resolver_address, "upstream dns resolver server (<address:port>)"),
         OPT_STRING('u', "user", &c.user, "run as given user"),
         OPT_BOOLEAN('d', "daemonize", &c.daemonize, "run as daemon (default: off)"),
-        /*OPT_BOOLEAN('t', "tcp-only", &c.tcp_only, "use tcp only (default: off)"),*/
         OPT_BOOLEAN('V', "verbose", &verbose, "show verbose logs (specify more -VVV to increase verbosity)"),
         OPT_STRING('l', "logfile", &c.logfile, "log file path (default: stdout)"),
         OPT_BOOLEAN(0, "gen-provider-keypair", &gen_provider_keypair, "generate provider key pair"),
@@ -367,11 +366,13 @@ main(int argc, const char **argv)
         exit(1);
     }
 
-    if (udp_listern_bind(&c) != 0) {
+    if (udp_listener_bind(&c) != 0 ||
+        tcp_listener_bind(&c) != 0) {
         exit(1);
     }
 
-    if (udp_listener_start(&c) != 0) {
+    if (udp_listener_start(&c) != 0 ||
+        tcp_listener_start(&c) != 0) {
         logger(LOG_ERR, "Unable to start udp listener.");
         exit(1);
     }
@@ -380,5 +381,10 @@ main(int argc, const char **argv)
 
     event_base_dispatch(c.event_loop);
 
+    logger(LOG_INFO, "Stopping proxy");
+    udp_listener_stop(&c);
+    tcp_listener_stop(&c);
+    event_base_free(c.event_loop);
+
     return 0;
 }