From e9e1ed79779da4be2a6cf9d2229fc10496e54cc7 Mon Sep 17 00:00:00 2001
From: Takuya ASADA <syuu@cloudius-systems.com>
Date: Fri, 2 Jan 2015 04:41:11 +0900
Subject: [PATCH] Implement TCP client on native-stack

---
 net/native-stack.cc |  2 +-
 net/tcp-stack.hh    |  4 ++++
 net/tcp.cc          |  6 ++++++
 net/tcp.hh          | 28 +++++++++++++++++++++++++++-
 4 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/net/native-stack.cc b/net/native-stack.cc
index b67111f0df4..76b8cfcf827 100644
--- a/net/native-stack.cc
+++ b/net/native-stack.cc
@@ -185,7 +185,7 @@ native_network_stack::listen(socket_address sa, listen_options opts) {
 future<connected_socket>
 native_network_stack::connect(socket_address sa) {
     assert(sa.as_posix_sockaddr().sa_family == AF_INET);
-    return make_ready_future<connected_socket>(connected_socket(nullptr));
+    return make_ready_future<connected_socket>(tcpv4_connect(_inet.get_tcp(), sa));
 }
 
 using namespace std::chrono_literals;
diff --git a/net/tcp-stack.hh b/net/tcp-stack.hh
index e6149d1a44e..66316e010a5 100644
--- a/net/tcp-stack.hh
+++ b/net/tcp-stack.hh
@@ -9,6 +9,7 @@
 
 class listen_options;
 class server_socket;
+class connected_socket;
 
 namespace net {
 
@@ -19,6 +20,9 @@ class tcp;
 server_socket
 tcpv4_listen(tcp<ipv4_traits>& tcpv4, uint16_t port, listen_options opts);
 
+connected_socket
+tcpv4_connect(tcp<ipv4_traits>& tcpv4, socket_address sa);
+
 }
 
 #endif
diff --git a/net/tcp.cc b/net/tcp.cc
index d41b998e87c..9b4a7e15e5a 100644
--- a/net/tcp.cc
+++ b/net/tcp.cc
@@ -127,5 +127,11 @@ tcpv4_listen(tcp<ipv4_traits>& tcpv4, uint16_t port, listen_options opts) {
 			tcpv4, port, opts));
 }
 
+connected_socket
+tcpv4_connect(tcp<ipv4_traits>& tcpv4, socket_address sa) {
+    return connected_socket(std::make_unique<native_connected_socket_impl<tcp<ipv4_traits>>>(
+        tcpv4.connect(sa)));
+}
+
 }
 
diff --git a/net/tcp.hh b/net/tcp.hh
index 749a205c433..00aaa8a0719 100644
--- a/net/tcp.hh
+++ b/net/tcp.hh
@@ -19,6 +19,7 @@
 #include <deque>
 #include <chrono>
 #include <experimental/optional>
+#include <random>
 
 #define CRYPTOPP_ENABLE_NAMESPACE_WEAK 1
 #include <cryptopp/md5.h>
@@ -300,6 +301,9 @@ private:
     inet_type& _inet;
     std::unordered_map<connid, lw_shared_ptr<tcb>, connid_hash> _tcbs;
     std::unordered_map<uint16_t, listener*> _listening;
+    std::random_device _rd;
+    std::default_random_engine _e;
+    std::uniform_int_distribution<uint16_t> _port_dist{41952, 65535};
 public:
     class connection {
         lw_shared_ptr<tcb> _tcb;
@@ -358,10 +362,11 @@ public:
         friend class tcp;
     };
 public:
-    explicit tcp(inet_type& inet) : _inet(inet) {}
+    explicit tcp(inet_type& inet) : _inet(inet), _e(_rd()) {}
     void received(packet p, ipaddr from, ipaddr to);
     bool forward(forward_hash& out_hash_data, packet& p, size_t off);
     listener listen(uint16_t port, size_t queue_length = 100);
+    connection connect(socket_address sa);
     net::hw_features hw_features() { return _inet._inet.hw_features(); }
 private:
     void send(ipaddr from, ipaddr to, packet p);
@@ -374,6 +379,27 @@ auto tcp<InetTraits>::listen(uint16_t port, size_t queue_length) -> listener {
     return listener(*this, port, queue_length);
 }
 
+template <typename InetTraits>
+auto tcp<InetTraits>::connect(socket_address sa) -> connection {
+    uint16_t src_port;
+    connid id;
+    auto src_ip = _inet._inet.host_address();
+    auto dst_ip = ipv4_address(sa);
+    auto dst_port = net::ntoh(sa.u.in.sin_port);
+
+    do {
+        src_port = _port_dist(_e);
+        id = connid{src_ip, dst_ip, src_port, dst_port};
+    } while (_inet._inet.netif()->hash2cpu(id.hash()) != engine.cpu_id()
+            || _tcbs.find(id) != _tcbs.end());
+
+    auto tcbp = make_lw_shared<tcb>(*this, id);
+    _tcbs.insert({id, tcbp});
+    tcbp->output();
+
+    return connection(tcbp);
+}
+
 template <typename InetTraits>
 bool tcp<InetTraits>::forward(forward_hash& out_hash_data, packet& p, size_t off) {
     auto th = p.get_header<tcp_hdr>(off);