Commit 2994d9a2 authored by Roger Dingledine's avatar Roger Dingledine
Browse files

Forward-port the checking of 

sin_addr.s_addr == 0 || sin->sin_port == 0.
This just happened on moria2, so I guess it happens rarely
on Linux as well as OS X.
We can't afford to accept OR conns from 0.0.0.0:0, since we
send created cells back to the first addr:port that matches,
and we'd better not send them to the wrong place.
So, let's drop them all for now, and see if we can find a pattern
later.


svn:r4028
parent 752c1811

trunk/src/or/connection.c

+45 −2
Changes for trunk/src/or/connection.c: 45 added lines, 2 removed lines.
Original line number Diff line number Diff line
@@ -476,6 +476,31 @@ static int connection_create_listener(const char *bindaddress, uint16_t bindport 
  return 0;

}



/** Do basic sanity checking on a newly received socket. Return 0

 * if it looks ok, else return -1. */

static int

check_sockaddr_in(struct sockaddr *sa, int len, int level)

{

  int ok = 1;

  struct sockaddr_in *sin=(struct sockaddr_in*)sa;



  if (len != sizeof(struct sockaddr_in)) {

    log_fn(level, "Length of address not as expected: %d vs %d",

           len,(int)sizeof(struct sockaddr_in));

    ok = 0;

  }

  if (sa->sa_family != AF_INET) {

    log_fn(level, "Family of address not as expected: %d vs %d",

           sa->sa_family, AF_INET);

    ok = 0;

  }

  if (sin->sin_addr.s_addr == 0 || sin->sin_port == 0) {

    log_fn(level, "Address for new connection has address/port equal to zero.");

    ok = 0;

  }

  return ok ? 0 : -1;

}



/** The listener connection <b>conn</b> told poll() it wanted to read.

 * Call accept() on conn-\>s, and add the new connection if necessary.

 */
@@ -484,9 +509,12 @@ static int connection_handle_listener_read(connection_t *conn, int new_type) { 
  connection_t *newconn;

  /* information about the remote peer when connecting to other routers */

  struct sockaddr_in remote;

  char addrbuf[256];

  /* length of the remote address. Must be an int, since accept() needs that. */

  int remotelen = sizeof(struct sockaddr_in);

  int remotelen = 256;

  char tmpbuf[INET_NTOA_BUF_LEN];

  tor_assert(remotelen >= sizeof(struct sockaddr_in));

  memset(addrbuf, 0, sizeof(addrbuf));



  news = accept(conn->s,(struct sockaddr *)&remote,&remotelen);

  if (!SOCKET_IS_POLLABLE(news)) {
@@ -516,6 +544,22 @@ static int connection_handle_listener_read(connection_t *conn, int new_type) { 


  set_socket_nonblocking(news);



  if (check_sockaddr_in((struct sockaddr*)addrbuf, remotelen, LOG_INFO)<0) {

    log_fn(LOG_INFO, "accept() returned a strange address; trying getsockname().");

    remotelen=256;

    memset(addrbuf, 0, sizeof(addrbuf));

    if (getsockname(news, (struct sockaddr*)addrbuf, &remotelen)<0) {

      log_fn(LOG_WARN, "getsockname() failed.");

    } else {

      if (check_sockaddr_in((struct sockaddr*)addrbuf, remotelen, LOG_WARN)<0) {

        log_fn(LOG_WARN,"Something's wrong with this conn. Closing it.");

        tor_close_socket(news);

        return 0;

      }

    }

  }

  memcpy(&remote, addrbuf, sizeof(struct sockaddr_in));



  /* process entrance policies here, before we even create the connection */

  if (new_type == CONN_TYPE_AP) {

    /* check sockspolicy to see if we should accept it */
@@ -544,7 +588,6 @@ static int connection_handle_listener_read(connection_t *conn, int new_type) { 
  /* remember the remote address */

  newconn->address = tor_malloc(INET_NTOA_BUF_LEN);

  tor_inet_ntoa(&remote.sin_addr, newconn->address, INET_NTOA_BUF_LEN);



  newconn->addr = ntohl(remote.sin_addr.s_addr);

  newconn->port = ntohs(remote.sin_port);