From 76f11a2defa6e30ebd19ff0f68b6f51d948e08e7 Mon Sep 17 00:00:00 2001
From: Quentin Dufour <quentin.dufour@inria.fr>
Date: Mon, 11 Mar 2019 11:25:34 +0100
Subject: [PATCH] Working TCP echo

---
 src/tor_echo.c | 71 ++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 52 insertions(+), 19 deletions(-)

diff --git a/src/tor_echo.c b/src/tor_echo.c
index d07d2bc..6457576 100644
--- a/src/tor_echo.c
+++ b/src/tor_echo.c
@@ -5,8 +5,9 @@
 #include "tor_ctl.h"
 #include "evt_core.h"
 #include "net_tools.h"
+#include "url.h"
 
-void create_onion_services(struct tor_os_str* tos, struct tor_ctl* tctl, uint16_t* ports, int ports_count) {
+void te_create_onion_services(struct tor_os_str* tos, struct tor_ctl* tctl, uint16_t* ports, int ports_count) {
     tor_os_create (tos, "onion_services.pub", "onion_services.txt", ports_count);
     tor_os_read (tos);
 
@@ -23,24 +24,54 @@ void create_onion_services(struct tor_os_str* tos, struct tor_ctl* tctl, uint16_
     }
 }
 
-int on_tcp(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+int te_on_tcp_co(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
+  int conn_sock1, conn_sock2;
+  struct sockaddr_in addr;
+  socklen_t in_len;
+  char url[1024], port[6];
+  struct evt_core_cat local_cat = {0};
+  struct evt_core_fdinfo to_fdinfo = {0};
+  to_fdinfo.cat = &local_cat;
+  to_fdinfo.url = url;
+
+  in_len = sizeof(addr);
+  conn_sock1 = accept(fdinfo->fd, (struct sockaddr*)&addr, &in_len);
+
+  if (conn_sock1 == -1) goto co_error;
+
+  url_get_port(port, fdinfo->url);
+
+  to_fdinfo.fd = conn_sock1;
+  to_fdinfo.cat->name = "tcp-all";
+  sprintf(to_fdinfo.url, "tcp:all:127.0.0.1:%s", port);
+  evt_core_add_fd (ctx, &to_fdinfo);
+
+  return 1;
+
+co_error:
+  perror("Failed to handle new connection");
+  exit(EXIT_FAILURE);
+}
+
+int te_on_tcp(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
   char buffer[1500];
   ssize_t nread, nwritten;
   struct sockaddr_in addr;
   socklen_t addrlen = sizeof(addr);
 
-  nread = recvfrom(fdinfo->fd, buffer, sizeof(buffer), MSG_TRUNC, (struct sockaddr*)&addr, &addrlen);
+  nread = recv(fdinfo->fd, buffer, sizeof(buffer), 0);
   if (nread == -1 && errno == EAGAIN) return 1; // Read done
-  if (nread <= 0 || nread > sizeof(buffer)) {
+  if (nread == 0) { fprintf(stderr, "WARN! Read 0 bytes.\n"); return 1; }
+  if (nread < 0 || nread > sizeof(buffer)) {
     fprintf(stderr, "Message is either truncated or an error occured. nread=%ld\n", nread);
     perror("read errno");
     exit(EXIT_FAILURE);
   }
 
-  nwritten = sendto(fdinfo->fd, buffer, nread, 0, (struct sockaddr*)&addr, addrlen);
+  nwritten = send(fdinfo->fd, buffer, nread, 0);
   // @FIXME don't support EAGAIN on write. Could be intended, you don't think so?
   if (nwritten != nread) {
-    fprintf(stderr, "Didn't write the same number of bytes as read. nread=%ld, nwritten=%ld\n", nread, nwritten);
+    fprintf(stderr, "Didn't write the same number of bytes as read - not supported. nread=%ld, nwritten=%ld\n", nread, nwritten);
     perror("write errno");
     exit(EXIT_FAILURE);
   }
@@ -51,30 +82,31 @@ int main(int argc, char** argv) {
   setvbuf(stdout, NULL, _IONBF, 0);
   printf("~ torecho ~\n");
 
-  int tcp_serv_sock = 0;
+  int tcp_serv_sock = 0, err;
   struct evt_core_ctx evts = {0};
-  uint16_t ports = {7500};
-  int port_count = sizeof(ports[0]) / sizeof(ports);
+  uint16_t ports[] = {7500};
+  int ports_count = sizeof(ports[0]) / sizeof(ports);
   struct tor_os_str tos;
   struct tor_ctl tctl;
+  char url[1024];
 
   // 1. Register categories
   struct evt_core_cat tcp_co = {
     .app_ctx = NULL,
     .free_app_ctx = NULL,
-    .cb = on_tcp_co,
+    .cb = te_on_tcp_co,
     .err_cb = NULL,
-    .name = "tcp-all",
+    .name = "tcp-co",
     .flags = EPOLLIN,
     .socklist = NULL
   };
   struct evt_core_cat tcp_all = {
     .app_ctx = NULL,
     .free_app_ctx = NULL,
-    .cb = on_tcp,
+    .cb = te_on_tcp,
     .err_cb = NULL,
     .name = "tcp-all",
-    .flags = EPOLLIN | EPOLLOUT | EPOLLET,
+    .flags = EPOLLIN | EPOLLOUT | EPOLLET | EPOLLRDHUP,
     .socklist = NULL
   };
   evt_core_init(&evts);
@@ -83,21 +115,22 @@ int main(int argc, char** argv) {
   printf("--- Categories created\n");
 
   // 2. Create or load onion services
-  create_onion_services (&tos, &tctl, ports, ports_count);
+  te_create_onion_services (&tos, &tctl, ports, ports_count);
   printf("--- Onion services created\n");
 
   // 3. Create TCP server
-  tcp_serv_sock = create_tcp_server ("127.0.0.1", ports[0]);
+  sprintf(url, "%d", ports[0]);
+  tcp_serv_sock = create_tcp_server ("0.0.0.0", url);
+  err = listen(tcp_serv_sock, SOMAXCONN);
 
-  char url[1024];
   struct evt_core_cat cat = {0};
   struct evt_core_fdinfo fdinfo = {0};
   fdinfo.cat = &cat;
   fdinfo.url = url;
 
-  fdinfo.fd = udp_sock;
-  sprintf(url, "tcp:all:127.0.0.1:%s", port);
-  fdinfo.cat->name = "tcp-all";
+  fdinfo.fd = tcp_serv_sock;
+  sprintf(url, "tcp:co:127.0.0.1:%d", ports[0]);
+  fdinfo.cat->name = "tcp-co";
   evt_core_add_fd(&evts, &fdinfo);
   printf("--- TCP server is listening\n");