tor/src/or/connection_exit.c

/* Copyright 2001,2002 Roger Dingledine, Matej Pfajfar. */
/* See LICENSE for licensing information */
/* $Id$ */

#include "or.h"

int connection_exit_begin_conn(cell_t *cell, circuit_t *circ) {
  connection_t *n_stream;
  char *colon;

  if(!memchr(cell->payload+RELAY_HEADER_SIZE+STREAM_ID_SIZE,0,cell->length-RELAY_HEADER_SIZE-STREAM_ID_SIZE)) {
    log_fn(LOG_WARNING,"relay begin cell has no \\0. Dropping.");
    return 0;
  }
  colon = strchr(cell->payload+RELAY_HEADER_SIZE+STREAM_ID_SIZE, ':');
  if(!colon) {
    log_fn(LOG_WARNING,"relay begin cell has no colon. Dropping.");
    return 0;
  }
  *colon = 0;

  if(!atoi(colon+1)) { /* bad port */
    log_fn(LOG_DEBUG,"relay begin cell has invalid port. Dropping.");
    return 0;
  }

  log_fn(LOG_DEBUG,"Creating new exit connection.");
  n_stream = connection_new(CONN_TYPE_EXIT);
  if(!n_stream) {
    log_fn(LOG_DEBUG,"connection_new failed. Dropping.");
    return 0;
  }

  memcpy(n_stream->stream_id, cell->payload + RELAY_HEADER_SIZE, STREAM_ID_SIZE);
  n_stream->address = strdup(cell->payload + RELAY_HEADER_SIZE + STREAM_ID_SIZE);
  n_stream->port = atoi(colon+1);
  n_stream->state = EXIT_CONN_STATE_RESOLVING;
  n_stream->receiver_bucket = -1; /* edge connections don't do receiver buckets */
  n_stream->bandwidth = -1;
  n_stream->s = -1; /* not yet valid */
  n_stream->package_window = STREAMWINDOW_START;
  n_stream->deliver_window = STREAMWINDOW_START;
  if(connection_add(n_stream) < 0) { /* no space, forget it */
    log_fn(LOG_DEBUG,"connection_add failed. Dropping.");
    connection_free(n_stream);
    return 0;
  }

  /* add it into the linked list of streams on this circuit */
  n_stream->next_stream = circ->n_streams;
  circ->n_streams = n_stream;

  /* send it off to the gethostbyname farm */
  switch(dns_resolve(n_stream)) {
    case 1: /* resolve worked */
      if(connection_exit_connect(n_stream) >= 0)
        return 0;
      /* else fall through */
    case -1: /* resolve failed */
      log_fn(LOG_DEBUG,"Couldn't queue resolve request.");
      connection_remove(n_stream);
      connection_free(n_stream);
    case 0: /* resolve added to pending list */
  }
  return 0;
}

int connection_exit_connect(connection_t *conn) {
  int s; /* for the new socket */
  struct sockaddr_in dest_addr;

  if(router_compare_to_exit_policy(conn) < 0) {
    log_fn(LOG_INFO,"%s:%d failed exit policy. Closing.", conn->address, conn->port);
    return -1;
  }

  /* all the necessary info is here. Start the connect() */
  s=socket(PF_INET,SOCK_STREAM,IPPROTO_TCP);
  if (s < 0) {
    log_fn(LOG_ERR,"Error creating network socket.");
    return -1;
  }
  set_socket_nonblocking(s);

  memset((void *)&dest_addr,0,sizeof(dest_addr));
  dest_addr.sin_family = AF_INET;
  dest_addr.sin_port = htons(conn->port);
  dest_addr.sin_addr.s_addr = htonl(conn->addr);

  log_fn(LOG_DEBUG,"Connecting to %s:%u.",conn->address,conn->port); 

  if(connect(s,(struct sockaddr *)&dest_addr,sizeof(dest_addr)) < 0) {
    if(!ERRNO_CONN_EINPROGRESS(errno)) {
      /* yuck. kill it. */
      perror("connect");
      log_fn(LOG_DEBUG,"Connect failed.");
      return -1;
    } else {
      /* it's in progress. set state appropriately and return. */
      conn->s = s;
      connection_set_poll_socket(conn);
      conn->state = EXIT_CONN_STATE_CONNECTING;

      log_fn(LOG_DEBUG,"connect in progress, socket %d.",s);
      connection_watch_events(conn, POLLOUT | POLLIN | POLLERR);
      /* writable indicates finish, readable indicates broken link,
         error indicates broken link in windowsland. */
      return 0;
    }
  }

  /* it succeeded. we're connected. */
  log_fn(LOG_DEBUG,"Connection to %s:%u established.",conn->address,conn->port);

  conn->s = s;
  connection_set_poll_socket(conn);
  conn->state = EXIT_CONN_STATE_OPEN;
  if(connection_wants_to_flush(conn)) { /* in case there are any queued data cells */
    log_fn(LOG_ERR,"tell roger: newly connected conn had data waiting!");
//    connection_start_writing(conn);
  }
//   connection_process_inbuf(conn);
  connection_watch_events(conn, POLLIN);

  /* also, deliver a 'connected' cell back through the circuit. */
  return connection_edge_send_command(conn, circuit_get_by_conn(conn), RELAY_COMMAND_CONNECTED);
}

/*
  Local Variables:
  mode:c
  indent-tabs-mode:nil
  c-basic-offset:2
  End:
*/