From 2cad381036c7fe684b03b734e949cb2bd9d5f222 Mon Sep 17 00:00:00 2001
From: Max Lv <max.c.lv@gmail.com>
Date: Sun, 26 Nov 2017 14:32:26 +0800
Subject: [PATCH] Refine TFO in redir and server mode

---
 configure.ac   |  2 +-
 src/netutils.h |  9 ++++++---
 src/redir.c    |  2 +-
 src/server.c   | 24 +++++++++++++++---------
 4 files changed, 23 insertions(+), 14 deletions(-)

diff --git a/configure.ac b/configure.ac
index 1f61dae3..cea85f66 100755
--- a/configure.ac
+++ b/configure.ac
@@ -139,7 +139,7 @@ AM_CONDITIONAL(BUILD_REDIRECTOR, test "$os_support" = "linux")
 AM_CONDITIONAL(BUILD_WINCOMPAT, test "$os_support" = "mingw")
 
 dnl Checks for header files.
-AC_CHECK_HEADERS([limits.h stdint.h inttypes.h arpa/inet.h fcntl.h langinfo.h locale.h netdb.h netinet/in.h stdlib.h string.h strings.h unistd.h sys/ioctl.h linux/random.h])
+AC_CHECK_HEADERS([limits.h stdint.h inttypes.h arpa/inet.h fcntl.h langinfo.h locale.h linux/tcp.h netinet/tcp.h netdb.h netinet/in.h stdlib.h string.h strings.h unistd.h sys/ioctl.h linux/random.h])
 
 dnl A special check required for <net/if.h> on Darwin. See
 dnl http://www.gnu.org/software/autoconf/manual/html_node/Header-Portability.html.
diff --git a/src/netutils.h b/src/netutils.h
index 4cfe748d..3845d251 100644
--- a/src/netutils.h
+++ b/src/netutils.h
@@ -25,13 +25,16 @@
 
 #include <sys/socket.h>
 
-#if defined(__linux__)
-#include <netdb.h>
+#if HAVE_LINUX_TCP_H
 #include <linux/tcp.h>
-#else
+#elif defined(HAVE_NETINET_TCP_H)
 #include <netinet/tcp.h>
 #endif
 
+#ifdef HAVE_NETDB_H
+#include <netdb.h>
+#endif
+
 /* MPTCP_ENABLED setsockopt values for kernel 4 & 3, best behaviour to be independant of kernel version is to test from newest to the latest values */
 #ifndef MPTCP_ENABLED
 static const char mptcp_enabled_values[] = { 42, 26, 0 };
diff --git a/src/redir.c b/src/redir.c
index 70915f06..99db0d80 100644
--- a/src/redir.c
+++ b/src/redir.c
@@ -558,7 +558,7 @@ remote_send_cb(EV_P_ ev_io *w, int revents)
             if(setsockopt(remote->fd, IPPROTO_TCP, TCP_FASTOPEN_CONNECT,
                         (void *)&optval, sizeof(optval)) < 0)
                 FATAL("failed to set TCP_FASTOPEN_CONNECT");
-            s = connect(remote->fd, (struct sockaddr *)&(remote->addr), remote->addr_len);
+            s = connect(remote->fd, remote->addr, get_sockaddr_len(remote->addr));
             if (s == 0)
                 s = send(remote->fd, remote->buf->data, remote->buf->len, 0);
 #elif defined(MSG_FASTOPEN)
diff --git a/src/server.c b/src/server.c
index bec12041..cd9ae9ad 100644
--- a/src/server.c
+++ b/src/server.c
@@ -506,9 +506,19 @@ connect_to_remote(EV_P_ struct addrinfo *res,
 
     remote_t *remote = new_remote(sockfd);
 
-#ifdef TCP_FASTOPEN
     if (fast_open) {
-#ifdef __APPLE__
+#if defined(TCP_FASTOPEN_CONNECT)
+        int optval = 1;
+        if(setsockopt(sockfd, IPPROTO_TCP, TCP_FASTOPEN_CONNECT,
+                    (void *)&optval, sizeof(optval)) < 0)
+            FATAL("failed to set TCP_FASTOPEN_CONNECT");
+        int s = connect(sockfd, res->ai_addr, res->ai_addrlen);
+        if (s == 0)
+            s = send(sockfd, server->buf->data, server->buf->len, 0);
+#elif defined(MSG_FASTOPEN)
+        ssize_t s = sendto(sockfd, server->buf->data, server->buf->len,
+                MSG_FASTOPEN, res->ai_addr, res->ai_addrlen);
+#elif defined(CONNECT_DATA_IDEMPOTENT)
         ((struct sockaddr_in *)(res->ai_addr))->sin_len = sizeof(struct sockaddr_in);
         sa_endpoints_t endpoints;
         memset((char *)&endpoints, 0, sizeof(endpoints));
@@ -521,16 +531,13 @@ connect_to_remote(EV_P_ struct addrinfo *res,
         size_t len;
         int s = connectx(sockfd, &endpoints, SAE_ASSOCID_ANY, CONNECT_DATA_IDEMPOTENT,
                          &iov, 1, &len, NULL);
-        if (s == 0) {
+        if (s == 0)
             s = len;
-        }
 #else
-        ssize_t s = sendto(sockfd, server->buf->data, server->buf->len,
-                           MSG_FASTOPEN, res->ai_addr, res->ai_addrlen);
+        FATAL("fast open is not enabled in this build");
 #endif
         if (s == -1) {
-            if (errno == CONNECT_IN_PROGRESS || errno == EAGAIN
-                || errno == EWOULDBLOCK) {
+            if (errno == CONNECT_IN_PROGRESS) {
                 // The remote server doesn't support tfo or it's the first connection to the server.
                 // It will automatically fall back to conventional TCP.
             } else if (errno == EOPNOTSUPP || errno == EPROTONOSUPPORT ||
@@ -546,7 +553,6 @@ connect_to_remote(EV_P_ struct addrinfo *res,
             server->buf->len -= s;
         }
     }
-#endif
 
     if (!fast_open) {
         int r = connect(sockfd, res->ai_addr, res->ai_addrlen);