r7299@Kushana: nickm | 2006-08-10 01:08:58 -0700

Patch from Tup to add support for transparent AP connections: this basically bundles the functionality of trans-proxy-tor into the tor mainline.  Now hosts with compliant pf/netfilter implementations can redirect TCP connections straight to Tor without diverting through SOCKS.


svn:r7007
This commit is contained in:
Nick Mathewson 2006-08-10 09:01:37 +00:00
parent 8cbd03fdaf
commit 5cff4164a0
8 changed files with 215 additions and 10 deletions

View File

@ -56,6 +56,26 @@ if test x$eventdns = xtrue; then
AC_DEFINE([USE_EVENTDNS], 1, "Define to 1 if we'll be using eventdns.c")
fi
AC_ARG_ENABLE(transparent,
AC_HELP_STRING(--disable-transparent, disable transparent proxy support),
[case "${enableval}" in
yes) transparent=true ;;
no) transparent=false ;;
*) AC_MSG_ERROR(bad value for --enable-transparent) ;;
esac], [transparent=true])
if test x$transparent = xtrue; then
AC_DEFINE(USE_TRANSPARENT, 1, "Define to enable transparent proxy support")
case $host in
*-*-linux* )
AC_DEFINE(TRANS_NETFILTER, 1, "Define for transparent netfilter") ;;
*-*-openbsd*)
AC_DEFINE(TRANS_PF, 1, "Define for transparent pf")
AC_DEFINE(OPENBSD, 1, "Define to handle pf on OpenBSD properly") ;;
*-*-*bsd* )
AC_DEFINE(TRANS_PF, 1, "Define for transparent pf") ;;
esac
fi
case $host in
*-*-solaris* )
AC_DEFINE(_REENTRANT, 1, [Define on some platforms to activate x_r() functions in time.h])

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@ -235,6 +235,8 @@ static config_var_t _option_vars[] = {
VAR("TrackHostExits", CSV, TrackHostExits, NULL),
VAR("TrackHostExitsExpire",INTERVAL, TrackHostExitsExpire, "30 minutes"),
OBSOLETE("TrafficShaping"),
VAR("TransListenAddress", LINELIST, TransListenAddress, NULL),
VAR("TransPort", UINT, TransPort, "0"),
VAR("UseEntryGuards", BOOL, UseEntryGuards, "1"),
VAR("User", STRING, User, NULL),
VAR("V1AuthoritativeDirectory",BOOL, V1AuthoritativeDir, "0"),
@ -2067,6 +2069,7 @@ options_validate(or_options_t *old_options, or_options_t *options,
REJECT("SocksPort must be defined if SocksListenAddress is defined.");
#endif
/* XXX TransListenAddress should be checked here as well */
if (options->SocksListenAddress) {
config_line_t *line = NULL;
char *address = NULL;
@ -2144,8 +2147,12 @@ options_validate(or_options_t *old_options, or_options_t *options,
if (options->SocksPort < 0 || options->SocksPort > 65535)
REJECT("SocksPort option out of bounds.");
if (options->SocksPort == 0 && options->ORPort == 0)
REJECT("SocksPort and ORPort are both undefined? Quitting.");
if (options->TransPort < 0 || options->TransPort > 65535)
REJECT("TransPort option out of bounds.");
if (options->SocksPort == 0 && options->TransPort == 0 &&
options->ORPort == 0)
REJECT("SocksPort, TransPort, and ORPort are all undefined? Quitting.");
if (options->ControlPort < 0 || options->ControlPort > 65535)
REJECT("ControlPort option out of bounds.");
@ -2153,6 +2160,11 @@ options_validate(or_options_t *old_options, or_options_t *options,
if (options->DirPort < 0 || options->DirPort > 65535)
REJECT("DirPort option out of bounds.");
#ifndef USE_TRANSPARENT
if (options->TransPort || options->TransListenAddress)
REJECT("TransPort and TransListenAddress are disabled in this build.");
#endif
if (options->StrictExitNodes &&
(!options->ExitNodes || !strlen(options->ExitNodes)) &&
(!old_options ||

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@ -16,7 +16,8 @@ const char connection_c_id[] =
static connection_t *connection_create_listener(const char *listenaddress,
uint16_t listenport, int type);
static int connection_init_accepted_conn(connection_t *conn);
static int connection_init_accepted_conn(connection_t *conn,
uint8_t listener_type);
static int connection_handle_listener_read(connection_t *conn, int new_type);
static int connection_receiver_bucket_should_increase(or_connection_t *conn);
static int connection_finished_flushing(connection_t *conn);
@ -44,6 +45,7 @@ conn_type_to_string(int type)
case CONN_TYPE_OR: return "OR";
case CONN_TYPE_EXIT: return "Exit";
case CONN_TYPE_AP_LISTENER: return "Socks listener";
case CONN_TYPE_AP_TRANS_LISTENER: return "Transparent listener";
case CONN_TYPE_AP: return "Socks";
case CONN_TYPE_DIR_LISTENER: return "Directory listener";
case CONN_TYPE_DIR: return "Directory";
@ -69,6 +71,7 @@ conn_state_to_string(int type, int state)
switch (type) {
case CONN_TYPE_OR_LISTENER:
case CONN_TYPE_AP_LISTENER:
case CONN_TYPE_AP_TRANS_LISTENER:
case CONN_TYPE_DIR_LISTENER:
case CONN_TYPE_CONTROL_LISTENER:
if (state == LISTENER_STATE_READY)
@ -93,6 +96,7 @@ conn_state_to_string(int type, int state)
break;
case CONN_TYPE_AP:
switch (state) {
case AP_CONN_STATE_ORIGDST_WAIT:
case AP_CONN_STATE_SOCKS_WAIT: return "waiting for dest info";
case AP_CONN_STATE_RENDDESC_WAIT: return "waiting for rendezvous desc";
case AP_CONN_STATE_CONTROLLER_WAIT: return "waiting for controller";
@ -786,7 +790,7 @@ connection_handle_listener_read(connection_t *conn, int new_type)
return 0; /* no need to tear down the parent */
}
if (connection_init_accepted_conn(newconn) < 0) {
if (connection_init_accepted_conn(newconn, conn->type) < 0) {
connection_mark_for_close(newconn);
return 0;
}
@ -797,7 +801,7 @@ connection_handle_listener_read(connection_t *conn, int new_type)
* If conn is an OR, start the tls handshake.
*/
static int
connection_init_accepted_conn(connection_t *conn)
connection_init_accepted_conn(connection_t *conn, uint8_t listener_type)
{
connection_start_reading(conn);
@ -806,7 +810,14 @@ connection_init_accepted_conn(connection_t *conn)
control_event_or_conn_status(TO_OR_CONN(conn), OR_CONN_EVENT_NEW);
return connection_tls_start_handshake(TO_OR_CONN(conn), 1);
case CONN_TYPE_AP:
conn->state = AP_CONN_STATE_SOCKS_WAIT;
switch (listener_type) {
case CONN_TYPE_AP_LISTENER:
conn->state = AP_CONN_STATE_SOCKS_WAIT;
break;
case CONN_TYPE_AP_TRANS_LISTENER:
conn->state = AP_CONN_STATE_ORIGDST_WAIT;
break;
}
break;
case CONN_TYPE_DIR:
conn->purpose = DIR_PURPOSE_SERVER;
@ -1046,6 +1057,10 @@ retry_all_listeners(int force, smartlist_t *replaced_conns,
options->SocksPort, "127.0.0.1", force,
replaced_conns, new_conns, 0)<0)
return -1;
if (retry_listeners(CONN_TYPE_AP_TRANS_LISTENER, options->TransListenAddress,
options->TransPort, "127.0.0.1", force,
replaced_conns, new_conns, 0)<0)
return -1;
if (retry_listeners(CONN_TYPE_CONTROL_LISTENER,
options->ControlListenAddress,
options->ControlPort, "127.0.0.1", force,
@ -1260,6 +1275,7 @@ connection_handle_read(connection_t *conn)
case CONN_TYPE_OR_LISTENER:
return connection_handle_listener_read(conn, CONN_TYPE_OR);
case CONN_TYPE_AP_LISTENER:
case CONN_TYPE_AP_TRANS_LISTENER:
return connection_handle_listener_read(conn, CONN_TYPE_AP);
case CONN_TYPE_DIR_LISTENER:
return connection_handle_listener_read(conn, CONN_TYPE_DIR);
@ -1896,6 +1912,7 @@ connection_is_listener(connection_t *conn)
{
if (conn->type == CONN_TYPE_OR_LISTENER ||
conn->type == CONN_TYPE_AP_LISTENER ||
conn->type == CONN_TYPE_AP_TRANS_LISTENER ||
conn->type == CONN_TYPE_DIR_LISTENER ||
conn->type == CONN_TYPE_CONTROL_LISTENER)
return 1;
@ -2248,6 +2265,7 @@ assert_connection_ok(connection_t *conn, time_t now)
{
case CONN_TYPE_OR_LISTENER:
case CONN_TYPE_AP_LISTENER:
case CONN_TYPE_AP_TRANS_LISTENER:
case CONN_TYPE_DIR_LISTENER:
case CONN_TYPE_CONTROL_LISTENER:
tor_assert(conn->state == LISTENER_STATE_READY);

View File

@ -17,6 +17,7 @@ const char connection_edge_c_id[] =
static smartlist_t *redirect_exit_list = NULL;
static int connection_ap_handshake_process_socks(edge_connection_t *conn);
static int connection_ap_process_transparent(edge_connection_t *conn);
/** An AP stream has failed/finished. If it hasn't already sent back
* a socks reply, send one now (based on endreason). Also set
@ -80,6 +81,7 @@ connection_edge_reached_eof(edge_connection_t *conn)
/** Handle new bytes on conn->inbuf based on state:
* - If it's waiting for socks info, try to read another step of the
* socks handshake out of conn->inbuf.
* - If it's waiting for the original destination, fetch it.
* - If it's open, then package more relay cells from the stream.
* - Else, leave the bytes on inbuf alone for now.
*
@ -98,6 +100,12 @@ connection_edge_process_inbuf(edge_connection_t *conn, int package_partial)
return -1;
}
return 0;
case AP_CONN_STATE_ORIGDST_WAIT:
if (connection_ap_process_transparent(conn) < 0) {
/* already marked */
return -1;
}
return 0;
case AP_CONN_STATE_OPEN:
case EXIT_CONN_STATE_OPEN:
if (connection_edge_package_raw_inbuf(conn, package_partial) < 0) {
@ -234,6 +242,7 @@ connection_edge_finished_flushing(edge_connection_t *conn)
connection_edge_consider_sending_sendme(conn);
return 0;
case AP_CONN_STATE_SOCKS_WAIT:
case AP_CONN_STATE_ORIGDST_WAIT:
case AP_CONN_STATE_RENDDESC_WAIT:
case AP_CONN_STATE_CIRCUIT_WAIT:
case AP_CONN_STATE_CONNECT_WAIT:
@ -1216,6 +1225,89 @@ connection_ap_handshake_rewrite_and_attach(edge_connection_t *conn,
return 0; /* unreached but keeps the compiler happy */
}
/** Fetch the original destination address and port from a
* system-specific interface and put them into a
* socks_request_t as if they came from a socks request.
*
* Return -1 if an error prevents fetching the destination,
* else return 0.
*/
static int
connection_ap_get_original_destination(edge_connection_t *conn,
socks_request_t *req)
{
#ifdef TRANS_NETFILTER
/* Linux 2.4+ */
struct sockaddr_in orig_dst;
socklen_t orig_dst_len = sizeof(orig_dst);
char tmpbuf[INET_NTOA_BUF_LEN];
if (getsockopt(conn->_base.s, SOL_IP, SO_ORIGINAL_DST,
(struct sockaddr*)&orig_dst, &orig_dst_len) < 0) {
int e = tor_socket_errno(conn->_base.s);
log_warn(LD_NET, "getsockopt() failed: %s", tor_socket_strerror(e));
return -1;
}
tor_inet_ntoa(&orig_dst.sin_addr, tmpbuf, sizeof(tmpbuf));
strlcpy(req->address, tmpbuf, sizeof(req->address));
req->port = ntohs(orig_dst.sin_port);
#endif
#ifdef TRANS_PF
struct sockaddr_in proxy_addr;
socklen_t proxy_addr_len = sizeof(proxy_addr);
char tmpbuf[INET_NTOA_BUF_LEN];
struct pfioc_natlook pnl;
int pf = -1;
if (getsockname(conn->_base.s, (struct sockaddr*)&proxy_addr,
&proxy_addr_len) < 0) {
int e = tor_socket_errno(conn->_base.s);
log_warn(LD_NET, "getsockname() failed: %s", tor_socket_strerror(e));
return -1;
}
memset(&pnl, 0, sizeof(pnl));
pnl.af = AF_INET;
pnl.proto = IPPROTO_TCP;
pnl.direction = PF_OUT;
pnl.saddr.v4.s_addr = htonl(conn->_base.addr);
pnl.sport = htons(conn->_base.port);
pnl.daddr.v4.s_addr = proxy_addr.sin_addr.s_addr;
pnl.dport = proxy_addr.sin_port;
/* XXX We should open the /dev/pf device once and close it at cleanup time
* instead of reopening it for every connection. Ideally, it should be
* opened before dropping privs. */
#ifdef OPENBSD
/* only works on OpenBSD */
pf = open("/dev/pf", O_RDONLY);
#else
/* works on NetBSD and FreeBSD */
pf = open("/dev/pf", O_RDWR);
#endif
if (pf < 0) {
log_warn(LD_NET, "open(\"/dev/pf\") failed: %s", strerror(errno));
return -1;
}
if (ioctl(pf, DIOCNATLOOK, &pnl) < 0) {
log_warn(LD_NET, "ioctl(DIOCNATLOOK) failed: %s", strerror(errno));
close(pf);
return -1;
}
close(pf);
tor_inet_ntoa(&pnl.rdaddr.v4, tmpbuf, sizeof(tmpbuf));
strlcpy(req->address, tmpbuf, sizeof(req->address));
req->port = ntohs(pnl.rdport);
#endif
return 0;
}
/** connection_edge_process_inbuf() found a conn in state
* socks_wait. See if conn->inbuf has the right bytes to proceed with
* the socks handshake.
@ -1278,6 +1370,48 @@ connection_ap_handshake_process_socks(edge_connection_t *conn)
return connection_ap_handshake_rewrite_and_attach(conn, NULL);
}
/** connection_edge_process_inbuf() found a conn in state
* origdst_wait. Get the original destination and
* send it to connection_ap_handshake_rewrite_and_attach().
*
* Return -1 if an unexpected error with conn (and it should be marked
* for close), else return 0.
*/
static int
connection_ap_process_transparent(edge_connection_t *conn)
{
socks_request_t *socks;
or_options_t *options = get_options();
tor_assert(conn);
tor_assert(conn->_base.type == CONN_TYPE_AP);
tor_assert(conn->_base.state == AP_CONN_STATE_ORIGDST_WAIT);
tor_assert(conn->socks_request);
socks = conn->socks_request;
/* pretend that a socks handshake completed so we don't try to
* send a socks reply down a transparent conn */
socks->command = SOCKS_COMMAND_CONNECT;
socks->has_finished = 1;
log_debug(LD_APP,"entered.");
if (connection_ap_get_original_destination(conn, socks) < 0) {
log_warn(LD_APP,"Fetching original destination failed. Closing.");
connection_mark_unattached_ap(conn, 0);
return -1;
}
/* we have the original destination */
control_event_stream_status(conn, STREAM_EVENT_NEW);
if (options->LeaveStreamsUnattached) {
conn->_base.state = AP_CONN_STATE_CONTROLLER_WAIT;
return 0;
}
return connection_ap_handshake_rewrite_and_attach(conn, NULL);
}
/** Iterate over the two bytes of stream_id until we get one that is not
* already in use; return it. Return 0 if can't get a unique stream_id.
*/

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@ -1423,7 +1423,8 @@ handle_getinfo_helper(const char *question, char **answer)
origin_circuit_t *origin_circ = NULL;
if (conns[i]->type != CONN_TYPE_AP ||
conns[i]->marked_for_close ||
conns[i]->state == AP_CONN_STATE_SOCKS_WAIT)
conns[i]->state == AP_CONN_STATE_SOCKS_WAIT ||
conns[i]->state == AP_CONN_STATE_ORIGDST_WAIT)
continue;
conn = TO_EDGE_CONN(conns[i]);
switch (conn->_base.state)

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@ -712,6 +712,7 @@ hibernate_begin(int new_state, time_t now)
/* close listeners. leave control listener(s). */
while ((conn = connection_get_by_type(CONN_TYPE_OR_LISTENER)) ||
(conn = connection_get_by_type(CONN_TYPE_AP_LISTENER)) ||
(conn = connection_get_by_type(CONN_TYPE_AP_TRANS_LISTENER)) ||
(conn = connection_get_by_type(CONN_TYPE_DIR_LISTENER))) {
log_info(LD_NET,"Closing listener type %d", conn->type);
connection_mark_for_close(conn);

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@ -113,6 +113,15 @@
#error "Tor requires libevent to build."
#endif
#ifdef TRANS_NETFILTER
#include <linux/netfilter_ipv4.h>
#endif
#ifdef TRANS_PF
#include <net/if.h>
#include <net/pfvar.h>
#endif
#include "../common/crypto.h"
#include "../common/tortls.h"
#include "../common/log.h"
@ -215,7 +224,9 @@ typedef enum {
#define CONN_TYPE_CONTROL_LISTENER 12
/** Type for connections from user interface process. */
#define CONN_TYPE_CONTROL 13
#define _CONN_TYPE_MAX 13
/** Type for sockets listening for transparent proxy connections. */
#define CONN_TYPE_AP_TRANS_LISTENER 14
#define _CONN_TYPE_MAX 14
#define CONN_IS_EDGE(x) \
((x)->type == CONN_TYPE_EXIT || (x)->type == CONN_TYPE_AP)
@ -283,7 +294,10 @@ typedef enum {
#define AP_CONN_STATE_RESOLVE_WAIT 10
/** State for a SOCKS connection: ready to send and receive. */
#define AP_CONN_STATE_OPEN 11
#define _AP_CONN_STATE_MAX 11
/** State for a transparent proxy connection: waiting for original
* destination. */
#define AP_CONN_STATE_ORIGDST_WAIT 12
#define _AP_CONN_STATE_MAX 12
#define _DIR_CONN_STATE_MIN 1
/** State for connection to directory server: waiting for connect(). */
@ -1386,6 +1400,8 @@ typedef struct {
config_line_t *DirPolicy; /**< Lists of dir policy components */
/** Addresses to bind for listening for SOCKS connections. */
config_line_t *SocksListenAddress;
/** Addresses to bind for listening for transparent connections. */
config_line_t *TransListenAddress;
/** Addresses to bind for listening for OR connections. */
config_line_t *ORListenAddress;
/** Addresses to bind for listening for directory connections. */
@ -1407,6 +1423,7 @@ typedef struct {
* length (alpha in geometric distribution). */
int ORPort; /**< Port to listen on for OR connections. */
int SocksPort; /**< Port to listen on for SOCKS connections. */
int TransPort; /**< Port to listen on for transparent connections. */
int ControlPort; /**< Port to listen on for control connections. */
int DirPort; /**< Port to listen on for directory connections. */
int AssumeReachable; /**< Whether to publish our descriptor regardless. */

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@ -845,7 +845,9 @@ connection_edge_process_relay_cell_not_open(
conn->chosen_exit_name, ttl);
}
circuit_log_path(LOG_INFO,LD_APP,TO_ORIGIN_CIRCUIT(circ));
connection_ap_handshake_socks_reply(conn, NULL, 0, SOCKS5_SUCCEEDED);
/* don't send a socks reply to transparent conns */
if (!conn->socks_request->has_finished)
connection_ap_handshake_socks_reply(conn, NULL, 0, SOCKS5_SUCCEEDED);
/* handle anything that might have queued */
if (connection_edge_package_raw_inbuf(conn, 1) < 0) {
/* (We already sent an end cell if possible) */