From 204037b100d7ea8341f062790793538c48ecb8ae Mon Sep 17 00:00:00 2001
From: Max Lv <max.c.lv@gmail.com>
Date: Sun, 6 May 2018 11:41:29 +0800
Subject: [PATCH] Simplify the handshake part

---
 src/tunnel.c | 97 ++++++++++++++++------------------------------------
 src/tunnel.h |  3 --
 2 files changed, 29 insertions(+), 71 deletions(-)

diff --git a/src/tunnel.c b/src/tunnel.c
index 7970d33d..edd8a984 100644
--- a/src/tunnel.c
+++ b/src/tunnel.c
@@ -182,17 +182,6 @@ create_and_bind(const char *addr, const char *port)
     return listen_sock;
 }
 
-static void
-delayed_connect_cb(EV_P_ ev_timer *watcher, int revents)
-{
-    server_t *server = cork_container_of(watcher, server_t,
-                                         delayed_connect_watcher);
-    remote_t *remote = server->remote;
-
-    if (server->abuf != NULL)
-        remote_send_cb(EV_A_ & remote->send_ctx->io, revents);
-}
-
 static void
 server_recv_cb(EV_P_ ev_io *w, int revents)
 {
@@ -236,14 +225,6 @@ server_recv_cb(EV_P_ ev_io *w, int revents)
         return;
     }
 
-    if (server->abuf != NULL) {
-        ev_timer_stop(EV_A_ & server->delayed_connect_watcher);
-        bprepend(remote->buf, server->abuf, BUF_SIZE);
-        bfree(server->abuf);
-        ss_free(server->abuf);
-        server->abuf = NULL;
-    }
-
     int s = send(remote->fd, remote->buf->data, remote->buf->len, 0);
 
     if (s == -1) {
@@ -413,12 +394,10 @@ remote_send_cb(EV_P_ ev_io *w, int revents)
         int r = getpeername(remote->fd, (struct sockaddr *)&addr, &len);
         if (r == 0) {
             remote_send_ctx->connected = 1;
-            ev_io_stop(EV_A_ & remote_send_ctx->io);
             ev_timer_stop(EV_A_ & remote_send_ctx->watcher);
 
-            server->abuf = (buffer_t *)ss_malloc(sizeof(buffer_t));
-            buffer_t *abuf = server->abuf;
-            balloc(abuf, BUF_SIZE);
+            assert(remote->buf->len == 0);
+            buffer_t *abuf = remote->buf;
 
             ss_addr_t *sa = &server->destaddr;
             struct cork_ip ip;
@@ -467,18 +446,14 @@ remote_send_cb(EV_P_ ev_io *w, int revents)
             int err = crypto->encrypt(abuf, server->e_ctx, BUF_SIZE);
 
             if (err) {
-                bfree(abuf);
                 LOGE("invalid password or cipher");
                 close_and_free_remote(EV_A_ remote);
                 close_and_free_server(EV_A_ server);
                 return;
             }
 
-            ev_timer_start(EV_A_ & server->delayed_connect_watcher);
             ev_io_start(EV_A_ & remote->recv_ctx->io);
-            ev_io_start(EV_A_ & server->recv_ctx->io);
 
-            return;
         } else {
             ERROR("getpeername");
             // not connected
@@ -486,43 +461,36 @@ remote_send_cb(EV_P_ ev_io *w, int revents)
             close_and_free_server(EV_A_ server);
             return;
         }
+    }
+
+    if (remote->buf->len == 0) {
+        // close and free
+        close_and_free_remote(EV_A_ remote);
+        close_and_free_server(EV_A_ server);
+        return;
     } else {
-        if (remote->buf->len == 0 && server->abuf->len == 0) {
-            // close and free
-            close_and_free_remote(EV_A_ remote);
-            close_and_free_server(EV_A_ server);
+        // has data to send
+        ssize_t s = send(remote->fd, remote->buf->data + remote->buf->idx,
+                remote->buf->len, 0);
+        if (s == -1) {
+            if (errno != EAGAIN && errno != EWOULDBLOCK) {
+                ERROR("send");
+                // close and free
+                close_and_free_remote(EV_A_ remote);
+                close_and_free_server(EV_A_ server);
+            }
+            return;
+        } else if (s < remote->buf->len) {
+            // partly sent, move memory, wait for the next time to send
+            remote->buf->len -= s;
+            remote->buf->idx += s;
             return;
         } else {
-            // has data to send
-            if (server->abuf != NULL) {
-                assert(remote->buf->len == 0);
-                bprepend(remote->buf, server->abuf, BUF_SIZE);
-                bfree(server->abuf);
-                ss_free(server->abuf);
-                server->abuf = NULL;
-            }
-            ssize_t s = send(remote->fd, remote->buf->data + remote->buf->idx,
-                             remote->buf->len, 0);
-            if (s == -1) {
-                if (errno != EAGAIN && errno != EWOULDBLOCK) {
-                    ERROR("send");
-                    // close and free
-                    close_and_free_remote(EV_A_ remote);
-                    close_and_free_server(EV_A_ server);
-                }
-                return;
-            } else if (s < remote->buf->len) {
-                // partly sent, move memory, wait for the next time to send
-                remote->buf->len -= s;
-                remote->buf->idx += s;
-                return;
-            } else {
-                // all sent out, wait for reading
-                remote->buf->len = 0;
-                remote->buf->idx = 0;
-                ev_io_stop(EV_A_ & remote_send_ctx->io);
-                ev_io_start(EV_A_ & server->recv_ctx->io);
-            }
+            // all sent out, wait for reading
+            remote->buf->len = 0;
+            remote->buf->idx = 0;
+            ev_io_stop(EV_A_ & remote_send_ctx->io);
+            ev_io_start(EV_A_ & server->recv_ctx->io);
         }
     }
 }
@@ -606,9 +574,6 @@ new_server(int fd)
     ev_io_init(&server->recv_ctx->io, server_recv_cb, fd, EV_READ);
     ev_io_init(&server->send_ctx->io, server_send_cb, fd, EV_WRITE);
 
-    ev_timer_init(&server->delayed_connect_watcher,
-                  delayed_connect_cb, 0.05, 0);
-
     return server;
 }
 
@@ -626,10 +591,6 @@ free_server(server_t *server)
         crypto->ctx_release(server->d_ctx);
         ss_free(server->d_ctx);
     }
-    if (server->abuf != NULL) {
-        bfree(server->abuf);
-        ss_free(server->abuf);
-    }
     if (server->buf != NULL) {
         bfree(server->buf);
         ss_free(server->buf);
diff --git a/src/tunnel.h b/src/tunnel.h
index ae219345..cf4ff381 100644
--- a/src/tunnel.h
+++ b/src/tunnel.h
@@ -55,15 +55,12 @@ typedef struct server {
     int fd;
 
     buffer_t *buf;
-    buffer_t *abuf;
     cipher_ctx_t *e_ctx;
     cipher_ctx_t *d_ctx;
     struct server_ctx *recv_ctx;
     struct server_ctx *send_ctx;
     struct remote *remote;
     ss_addr_t destaddr;
-
-    ev_timer delayed_connect_watcher;
 } server_t;
 
 typedef struct remote_ctx {