FDs transferred over listen socket + other fixes

netcon/Intercept.c

@@ -195,7 +195,6 @@ int get_new_fd(int oversock)
 
 int send_cmd(int rpc_fd, char *cmd)
 {
-  //dwr(MSG_DEBUG, "\n---send_cmd[start]\n");
   pthread_mutex_lock(&lock);	
   char metabuf[BUF_SZ]; // portion of buffer which contains RPC metadata for debugging
 #ifdef VERBOSE
@@ -223,7 +222,7 @@ int send_cmd(int rpc_fd, char *cmd)
 #endif
   /* Combine command flag+payload with RPC metadata */
   memcpy(&metabuf[IDX_PAYLOAD], cmd, PAYLOAD_SZ);
-  usleep(10000);
+  usleep(1000);
   int n_write = write(rpc_fd, &metabuf, BUF_SZ);
   if(n_write < 0){
     dwr(MSG_DEBUG,"Error writing command to service (CMD = %d)\n", cmd[0]);
@@ -235,14 +234,12 @@ int send_cmd(int rpc_fd, char *cmd)
 
   if(n_write > 0) {
     if(cmd[0]==RPC_SOCKET) {
-    	dwr(MSG_DEBUG,"   waiting on get_new_fd()...\n");
     	ret = get_new_fd(fdret_sock);
     }
     if(cmd[0]==RPC_MAP) {
       ret = n_write;
     }
     if(cmd[0]==RPC_MAP_REQ || cmd[0]==RPC_CONNECT || cmd[0]==RPC_BIND) {
-    	dwr(MSG_DEBUG,"   waiting on get_retval()...\n");
     	ret = get_retval();
     }
     if(cmd[0]==RPC_LISTEN || cmd[0]==RPC_GETSOCKNAME) {
@@ -253,7 +250,6 @@ int send_cmd(int rpc_fd, char *cmd)
     ret = -1;
   }
   pthread_mutex_unlock(&lock);
-  //dwr(MSG_DEBUG, "---send_cmd[end]\n\n");
   return ret;
 }
 
@@ -529,10 +525,8 @@ int socket(SOCKET_SIG)
     memset(cmd, '\0', BUF_SZ);
     cmd[0] = RPC_MAP;
     memcpy(&cmd[1], &newfd, sizeof(newfd));
-	/* send fd mapping and get confirmation */
-	dwr(MSG_DEBUG, "pre-send_cmd\n");	
-	err = send_cmd(fdret_sock, cmd);
-	dwr(MSG_DEBUG, "post-send_cmd\n");
+  	/* send fd mapping and get confirmation */
+  	err = send_cmd(fdret_sock, cmd);
 	  
 	if(err > -1) {
 	  errno = ERR_OK;
@@ -611,7 +605,6 @@ int connect(CONNECT_SIG)
   }
 
   /* Assemble and send RPC */
-  int err;
   char cmd[BUF_SZ];
   memset(cmd, '\0', BUF_SZ);
   struct connect_st rpc_st;
@@ -621,7 +614,6 @@ int connect(CONNECT_SIG)
   memcpy(&rpc_st.__len, &__len, sizeof(socklen_t));
   cmd[0] = RPC_CONNECT;
   memcpy(&cmd[1], &rpc_st, sizeof(struct connect_st));
-
   return send_cmd(fdret_sock, cmd);
 }
 
@@ -672,7 +664,6 @@ int bind(BIND_SIG)
   }
 #endif
 
-  int err;
   /* make sure we don't touch any standard outputs */
   if(sockfd == STDIN_FILENO || sockfd == STDOUT_FILENO || sockfd == STDERR_FILENO)
     return(realbind(sockfd, addr, addrlen));
@@ -807,42 +798,31 @@ int accept(ACCEPT_SIG)
   /* The following line is required for libuv/nodejs to accept connections properly,
   however, this has the side effect of causing certain webservers to max out the CPU
   in an accept loop */
-  //fcntl(sockfd, F_SETFL, O_NONBLOCK);
+  fcntl(sockfd, F_SETFL, O_NONBLOCK);
+  int new_conn_socket = get_new_fd(sockfd);
 
-  char c[1];
-  int new_conn_socket;
-  int n = read(sockfd, c, sizeof(c)); /* Read signal byte */
-
-  if(n > 0)
+  if(new_conn_socket > 0)
   {
-    new_conn_socket = get_new_fd(fdret_sock);
+    //new_conn_socket = get_new_fd(fdret_sock);
     dwr(MSG_DEBUG, " accept(): RX: fd = (%d) over (%d)\n", new_conn_socket, fdret_sock);
-    if(new_conn_socket > 0) {
-      /* Send our local-fd number back to service so it can complete its mapping table */
-      memset(cmd, '\0', BUF_SZ);
-      cmd[0] = RPC_MAP;
-      memcpy(&cmd[1], &new_conn_socket, sizeof(new_conn_socket));
-
-      dwr(MSG_DEBUG, "accept(): sending perceived fd (%d) to service.\n", new_conn_socket);
-      int n_write = send_cmd(fdret_sock, cmd);
-
-      if(n_write < 0) {
-        errno = ECONNABORTED; /* TODO: Closest match, service unreachable */
-        handle_error("accept", "ECONNABORTED - Error sending perceived FD to service", -1);
-        return -1;
-      }
-      errno = ERR_OK;
-      dwr(MSG_DEBUG,"*accept()=%d\n", new_conn_socket);
-      handle_error("accept", "", new_conn_socket);
-      return new_conn_socket; /* OK */
-    }
-    else {
-      errno = ECONNABORTED; /* TODO: Closest match, service unreachable */
-      handle_error("accept", "ECONNABORTED - Error receiving new FD from service", -1);
+    /* Send our local-fd number back to service so it can complete its mapping table */
+    memset(cmd, '\0', BUF_SZ);
+    cmd[0] = RPC_MAP;
+    memcpy(&cmd[1], &new_conn_socket, sizeof(new_conn_socket));
+
+    dwr(MSG_DEBUG, "accept(): sending perceived fd (%d) to service.\n", new_conn_socket);
+    int n_write = send_cmd(fdret_sock, cmd);
+
+    if(n_write < 0) {
+      errno = ECONNABORTED; 
+      handle_error("accept", "ECONNABORTED - Error sending perceived FD to service", -1);
       return -1;
     }
+    errno = ERR_OK;
+    dwr(MSG_DEBUG,"accept()=%d\n", new_conn_socket);
+    handle_error("accept", "", new_conn_socket);
+    return new_conn_socket; /* OK */
   }
-
   errno = EAGAIN; /* necessary? */
   handle_error("accept", "EAGAIN - Error reading signal byte from service", -1);
   return -EAGAIN;
@@ -1024,8 +1004,7 @@ int getsockname(GETSOCKNAME_SIG)
     dwr(MSG_ERROR, "getsockname(): SYMBOL NOT FOUND.\n");
     return -1;
   }
-  return realgetsockname(sockfd, addr, addrlen);
-
+return realgetsockname(sockfd, addr, addrlen);
   /* assemble command */
   char cmd[BUF_SZ];
   struct getsockname_st rpc_st;

netcon/NetconEthernetTap.cpp

@@ -832,46 +832,38 @@ err_t NetconEthernetTap::nc_accept(void *arg, struct tcp_pcb *newpcb, err_t err)
 	int listening_fd = tap->_phy.getDescriptor(conn->dataSock);
 
   if(conn) {
-		ZT_PHY_SOCKFD_TYPE fds[2];
-		if(socketpair(PF_LOCAL, SOCK_STREAM, 0, fds) < 0) {
-			if(errno < 0) {
-				l->tap->send_return_value(conn, -1, errno);
-				dwr(MSG_ERROR, " nc_accept(): unable to create socketpair\n");
-				return ERR_MEM;
-			}
-		}
-		TcpConnection *new_tcp_conn = new TcpConnection();
-		new_tcp_conn->dataSock = tap->_phy.wrapSocket(fds[0], new_tcp_conn);
-		new_tcp_conn->rpcSock = conn->rpcSock;
-		new_tcp_conn->pcb = newpcb;
-		new_tcp_conn->their_fd = fds[1];
-		tap->tcp_connections.push_back(new_tcp_conn);
-		dwr(MSG_DEBUG, " nc_accept(): socketpair = {%d, %d}\n", fds[0], fds[1]);
-		int n, send_fd = tap->_phy.getDescriptor(conn->rpcSock);
-		if((n = send(listening_fd, "z", 1, MSG_NOSIGNAL)) < 0) {
-			dwr(MSG_ERROR, " nc_accept(): Error: [send(listening_fd,...) = MSG_NOSIGNAL].\n");
-			return -1;
+	ZT_PHY_SOCKFD_TYPE fds[2];
+	if(socketpair(PF_LOCAL, SOCK_STREAM, 0, fds) < 0) {
+		if(errno < 0) {
+			l->tap->send_return_value(conn, -1, errno);
+			dwr(MSG_ERROR, " nc_accept(): unable to create socketpair\n");
+			return ERR_MEM;
 		}
-		else if(n > 0) {
-			if(sock_fd_write(send_fd, fds[1]) > 0) {
-				close(fds[1]); // close other end of socketpair
-				new_tcp_conn->pending = true;
-			}
-			else {
-				dwr(MSG_ERROR, " nc_accept(%d): unable to send fd to client\n", listening_fd);
-			}
-    }
-    else {
-      dwr(MSG_ERROR, " nc_accept(%d): error writing signal byte (send_fd = %d, perceived_fd = %d)\n", listening_fd, send_fd, fds[1]);
-      return -1;
-    }
+	}
+	TcpConnection *new_tcp_conn = new TcpConnection();
+	new_tcp_conn->dataSock = tap->_phy.wrapSocket(fds[0], new_tcp_conn);
+	new_tcp_conn->rpcSock = conn->rpcSock;
+	new_tcp_conn->pcb = newpcb;
+	new_tcp_conn->their_fd = fds[1];
+	tap->tcp_connections.push_back(new_tcp_conn);
+	dwr(MSG_DEBUG, " nc_accept(): socketpair = {%d, %d}\n", fds[0], fds[1]);
+	int send_fd = tap->_phy.getDescriptor(conn->rpcSock);
+
+	if(sock_fd_write(listening_fd, fds[1]) < 0){
+		dwr(MSG_ERROR, " nc_accept(%d): error writing signal byte (listen_fd = %d, perceived_fd = %d)\n", listening_fd, send_fd, fds[1]);
+  		return -1;
+	}
+	else {
+		close(fds[1]); // close other end of socketpair
+		new_tcp_conn->pending = true;
+	}
     tap->lwipstack->_tcp_arg(newpcb, new Larg(tap, new_tcp_conn));
     tap->lwipstack->_tcp_recv(newpcb, nc_recved);
     tap->lwipstack->_tcp_err(newpcb, nc_err);
     tap->lwipstack->_tcp_sent(newpcb, nc_sent);
     tap->lwipstack->_tcp_poll(newpcb, nc_poll, 1);
     tcp_accepted(conn->pcb); // Let lwIP know that it can queue additional incoming connections
-		return ERR_OK;
+	return ERR_OK;
   }
   else {
     dwr(MSG_ERROR, " nc_accept(%d): can't locate Connection object for PCB.\n", listening_fd);
@@ -904,10 +896,10 @@ err_t NetconEthernetTap::nc_recved(void *arg, struct tcp_pcb *tpcb, struct pbuf
     return ERR_OK; // ?
   }
   if(p == NULL) {
-    if(l->conn) {
-			dwr(MSG_INFO, " nc_recved(): closing connection\n");
-			l->tap->closeConnection(l->conn);
-			return ERR_ABRT;
+    if(l->conn && !l->conn->listening) {
+		dwr(MSG_INFO, " nc_recved(): closing connection\n");
+	//	l->tap->closeConnection(l->conn);
+		return ERR_ABRT;
     }
     else {
       dwr(MSG_ERROR, " nc_recved(): can't locate connection via (arg)\n");
@@ -1092,11 +1084,11 @@ err_t NetconEthernetTap::nc_connected(void *arg, struct tcp_pcb *tpcb, err_t err
 void NetconEthernetTap::unload_rpc(void *data, pid_t &pid, pid_t &tid, int &rpc_count, char (timestamp[20]), char &cmd, void* &payload)
 {
 	unsigned char *buf = (unsigned char*)data;
-	memcpy(&pid, 			&buf[IDX_PID], 		sizeof(pid_t));
-	memcpy(&tid, 			&buf[IDX_TID], 		sizeof(pid_t));
-	memcpy(&rpc_count, 	&buf[IDX_COUNT], 		sizeof(int));
-	memcpy(timestamp, 	&buf[IDX_TIME], 		20);
-	memcpy(&cmd, 			&buf[IDX_PAYLOAD], 	sizeof(char));
+	memcpy(&pid, &buf[IDX_PID], sizeof(pid_t));
+	memcpy(&tid, &buf[IDX_TID], sizeof(pid_t));
+	memcpy(&rpc_count, &buf[IDX_COUNT], sizeof(int));
+	memcpy(timestamp, &buf[IDX_TIME], 20);
+	memcpy(&cmd, &buf[IDX_PAYLOAD], sizeof(char));
 }
 
 /*
@@ -1182,23 +1174,23 @@ void NetconEthernetTap::handle_getsockname(PhySocket *sock, void **uptr, struct
 	TcpConnection *conn = getConnectionByTheirFD(sock, getsockname_rpc->sockfd);
 	dwr(MSG_DEBUG, "handle_getsockname(): sockfd = %d\n", getsockname_rpc->sockfd);
 
-	/*
+/*
+	int port = conn->addr->sin_port;
 	int ip = conn->addr->sin_addr.s_addr;
 	unsigned char d[4];
 	d[0] = ip & 0xFF;
 	d[1] = (ip >>  8) & 0xFF;
 	d[2] = (ip >> 16) & 0xFF;
 	d[3] = (ip >> 24) & 0xFF;
-	int port = conn->addr->sin_port;
 	dwr(MSG_ERROR, " handle_getsockname(): returning address: %d.%d.%d.%d: %d\n", d[0],d[1],d[2],d[3], port);
-	*/
+*/
 
 	// Assemble address "command" to send to intercept
 	char retmsg[sizeof(struct sockaddr)];
 	memset(&retmsg, '\0', sizeof(retmsg));
 	dwr(MSG_ERROR, " handle_getsockname(): %d\n", sizeof(retmsg));
-	memcpy(&retmsg, conn->addr, sizeof(struct sockaddr));
-
+	if(conn == NULL) return;
+	memcpy(&retmsg, conn->addr, 1);
 	// Get connection's RPC fd and send structure containing bound address
 	int fd = _phy.getDescriptor(conn->rpcSock);
 	write(fd, &retmsg, sizeof(struct sockaddr));

netcon/common.inc.c

@@ -171,17 +171,17 @@ ssize_t sock_fd_read(int sock, void *buf, ssize_t bufsize, int *fd)
     size = recvmsg (sock, &msg, 0);
     if (size < 0) {
       perror ("recvmsg");
-      exit(1);
+      return -1;
     }
     cmsg = CMSG_FIRSTHDR(&msg);
     if (cmsg && cmsg->cmsg_len == CMSG_LEN(sizeof(int))) {
       if (cmsg->cmsg_level != SOL_SOCKET) {
         fprintf (stderr, "invalid cmsg_level %d\n",cmsg->cmsg_level);
-        exit(1);
+        return -1;
       }
       if (cmsg->cmsg_type != SCM_RIGHTS) {
           fprintf (stderr, "invalid cmsg_type %d\n",cmsg->cmsg_type);
-          exit(1);
+          return -1;
       }
 
       *fd = *((int *) CMSG_DATA(cmsg));
@@ -190,7 +190,7 @@ ssize_t sock_fd_read(int sock, void *buf, ssize_t bufsize, int *fd)
     size = read (sock, buf, bufsize);
     if (size < 0) {
       perror("read");
-      exit(1);
+      return -1;
     }
   }
   return size;