commit c8c6c60bfb9bc9eda73a8ff400ea2fb7ca0a7f3e Author: Robert Hogan robert@roberthogan.net Date: Sun Sep 19 13:34:02 2010 +0100

Use socket rather than address to determine connection type

In sendmsg() and sendto() we were inspecting the sock_addr_t structure to determine if the connection was Internet or not.

Since msg->msg_name is an optional value in sendmsg() and sendto() this could result in crashes because we weren't ensuring it was non-null.

Since it's optional we should have been inspecting the SO_DOMAIN of the connection's socket anyway - it will always be there.

Part of the fix for: http://code.google.com/p/torsocks/issues/detail?id=15 --- src/tsocks.c | 75 +++++++++++++++++++++++++++------------------------------- 1 files changed, 35 insertions(+), 40 deletions(-)

diff --git a/src/tsocks.c b/src/tsocks.c index fe2ec66..3a9327a 100644 --- a/src/tsocks.c +++ b/src/tsocks.c @@ -1732,9 +1732,10 @@ struct hostent *tsocks_getipnodebyname_guts(GETIPNODEBYNAME_SIGNATURE, struct ho

ssize_t tsocks_sendto_guts(SENDTO_SIGNATURE, ssize_t (*original_sendto)(SENDTO_SIGNATURE)) { - struct sockaddr_in *connaddr; int sock_type = -1; unsigned int sock_type_len = sizeof(sock_type); + int sock_domain = -1; + unsigned int sock_domain_len = sizeof(sock_domain);

/* See comment in close() */ if (!tsocks_init_complete) { @@ -1749,30 +1750,26 @@ ssize_t tsocks_sendto_guts(SENDTO_SIGNATURE, ssize_t (*original_sendto)(SENDTO_S

show_msg(MSGDEBUG, "Got sendto request\n");

- connaddr = (struct sockaddr_in *) to; - - /* Get the type of the socket */ - getsockopt(s, SOL_SOCKET, SO_TYPE, - (void *) &sock_type, &sock_type_len); + /* Get the domain of the socket */ + getsockopt(s, SOL_SOCKET, SO_DOMAIN, + (void *) &sock_domain, &sock_domain_len);

- show_msg(MSGDEBUG, "sin_family: %i " - "\n", - connaddr->sin_family); - - show_msg(MSGDEBUG, "sockopt: %i " - "\n", - sock_type); - - /* If this isn't an INET socket we can't */ - /* handle it, just call the real connect now */ - if ((connaddr->sin_family != AF_INET)) { - show_msg(MSGDEBUG, "Connection isn't a TCP stream ignoring\n"); + /* If this isn't an INET socket we can't handle it, just call the real + connect now */ + if ((sock_domain != PF_INET)) { + show_msg(MSGDEBUG, "Connection isn't an Internet socket ignoring\n"); return (ssize_t) original_sendto(s, buf, len, flags, to, tolen); }

#ifdef USE_TOR_DNS - /* If this a UDP socket */ - /* then we refuse it, since it is probably a DNS request */ + /* Get the type of the socket */ + getsockopt(s, SOL_SOCKET, SO_TYPE, + (void *) &sock_type, &sock_type_len); + + show_msg(MSGDEBUG, "sockopt: %i\n", sock_type); + + /* If this a UDP socket then we refuse it, since it is probably a DNS + request */ if ((sock_type != SOCK_STREAM)) { show_msg(MSGERR, "sendto: Connection is a UDP or ICMP stream, may be a " "DNS request or other form of leak: rejecting.\n"); @@ -1786,9 +1783,10 @@ ssize_t tsocks_sendto_guts(SENDTO_SIGNATURE, ssize_t (*original_sendto)(SENDTO_S

ssize_t tsocks_sendmsg_guts(SENDMSG_SIGNATURE, ssize_t (*original_sendmsg)(SENDMSG_SIGNATURE)) { - struct sockaddr_in *connaddr; int sock_type = -1; unsigned int sock_type_len = sizeof(sock_type); + int sock_domain = -1; + unsigned int sock_domain_len = sizeof(sock_domain);

/* See comment in close() */ if (!tsocks_init_complete) { @@ -1803,36 +1801,33 @@ ssize_t tsocks_sendmsg_guts(SENDMSG_SIGNATURE, ssize_t (*original_sendmsg)(SENDM

show_msg(MSGDEBUG, "Got sendmsg request\n");

- connaddr = (struct sockaddr_in *) msg->msg_name; + /* Get the domain of the socket */ + getsockopt(s, SOL_SOCKET, SO_DOMAIN, + (void *) &sock_domain, &sock_domain_len);

- /* Get the type of the socket */ - getsockopt(s, SOL_SOCKET, SO_TYPE, - (void *) &sock_type, &sock_type_len); - - show_msg(MSGDEBUG, "sin_family: %i " - "\n", - connaddr->sin_family); - - show_msg(MSGDEBUG, "sockopt: %i " - "\n", - sock_type); - - /* If this isn't an INET socket we can't */ - /* handle it, just call the real connect now */ - if ((connaddr->sin_family != AF_INET)) { - show_msg(MSGDEBUG, "Connection isn't a TCP stream ignoring\n"); + /* If this isn't an INET socket we can't handle it, just call the real + connect now */ + if ((sock_domain != PF_INET)) { + show_msg(MSGDEBUG, "Connection isn't an Internet socket ignoring\n"); return (ssize_t) original_sendmsg(s, msg, flags); }

#ifdef USE_TOR_DNS - /* If this a UDP socket */ - /* then we refuse it, since it is probably a DNS request */ + /* Get the type of the socket */ + getsockopt(s, SOL_SOCKET, SO_TYPE, + (void *) &sock_type, &sock_type_len); + + show_msg(MSGDEBUG, "sockopt: %i\n", sock_type); + + /* If this a UDP socket then we refuse it, since it is probably a DNS + request */ if ((sock_type != SOCK_STREAM)) { show_msg(MSGERR, "sendmsg: Connection is a UDP or ICMP stream, may be a " "DNS request or other form of leak: rejecting.\n"); return -1; } #endif + return (ssize_t) original_sendmsg(s, msg, flags); }