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/* Copyright 2001,2002 Roger Dingledine, Matej Pfajfar. */
/* See LICENSE for licensing information */
/* $Id$ */
#include "or.h"
int ap_handshake_process_socks(connection_t *conn) {
socks4_t socks4_info;
circuit_t *circ;
char tmpbuf[512];
int amt;
assert(conn);
log_fn(LOG_DEBUG,"entered.");
if(!conn->socks_version) { /* try to pull it in */
if(conn->inbuf_datalen < sizeof(socks4_t)) /* basic info available? */
return 0; /* not yet */
connection_fetch_from_buf((char *)&socks4_info,sizeof(socks4_t),conn);
log_fn(LOG_DEBUG,"Successfully read socks info.");
if(socks4_info.version != 4) {
log_fn(LOG_NOTICE,"Unrecognized version %d.",socks4_info.version);
ap_handshake_socks_reply(conn, SOCKS4_REQUEST_REJECT);
return -1;
}
conn->socks_version = socks4_info.version;
if(socks4_info.command != 1) { /* not a connect? we don't support it. */
log_fn(LOG_NOTICE,"command %d not '1'.",socks4_info.command);
ap_handshake_socks_reply(conn, SOCKS4_REQUEST_REJECT);
return -1;
}
conn->dest_port = ntohs(*(uint16_t*)&socks4_info.destport);
if(!conn->dest_port) {
log_fn(LOG_NOTICE,"Port is zero.");
ap_handshake_socks_reply(conn, SOCKS4_REQUEST_REJECT);
return -1;
}
log_fn(LOG_NOTICE,"Dest port is %d.",conn->dest_port);
if(socks4_info.destip[0] ||
socks4_info.destip[1] ||
socks4_info.destip[2] ||
!socks4_info.destip[3]) { /* not 0.0.0.x */
log_fn(LOG_NOTICE,"destip not in form 0.0.0.x.");
sprintf(tmpbuf, "%d.%d.%d.%d", socks4_info.destip[0],
socks4_info.destip[1], socks4_info.destip[2], socks4_info.destip[3]);
conn->dest_addr = strdup(tmpbuf);
log_fn(LOG_DEBUG,"Successfully read destip (%s)", conn->dest_addr);
}
}
if(!conn->read_username) { /* the socks spec says we've got to read stuff until we get a null */
amt = connection_find_on_inbuf("\0", 1, conn);
if(amt < 0) /* not there yet */
return 0;
if(amt > 500) {
log_fn(LOG_NOTICE,"username too long.");
ap_handshake_socks_reply(conn, SOCKS4_REQUEST_REJECT);
return -1;
}
connection_fetch_from_buf(tmpbuf,amt,conn);
conn->read_username = 1;
log_fn(LOG_DEBUG,"Successfully read username.");
}
if(!conn->dest_addr) { /* no dest_addr found yet */
amt = connection_find_on_inbuf("\0", 1, conn);
if(amt < 0) /* not there yet */
return 0;
if(amt > 500) {
log_fn(LOG_NOTICE,"dest_addr too long.");
ap_handshake_socks_reply(conn, SOCKS4_REQUEST_REJECT);
return -1;
}
connection_fetch_from_buf(tmpbuf,amt,conn);
conn->dest_addr = strdup(tmpbuf);
log_fn(LOG_NOTICE,"successfully read dest addr '%s'",
conn->dest_addr);
}
/* find the circuit that we should use, if there is one. */
circ = circuit_get_newest_ap();
if(!circ) {
log_fn(LOG_INFO,"No circuit ready. Closing.");
return -1;
}
circ->dirty = 1;
/* add it into the linked list of streams on this circuit */
log_fn(LOG_DEBUG,"attaching new conn to circ. n_aci %d.", circ->n_aci);
conn->next_stream = circ->p_streams;
circ->p_streams = conn;
assert(circ->cpath && circ->cpath->prev);
assert(circ->cpath->prev->state == CPATH_STATE_OPEN);
conn->cpath_layer = circ->cpath->prev;
if(ap_handshake_send_begin(conn, circ) < 0) {
circuit_close(circ);
return -1;
}
return 0;
}
int ap_handshake_send_begin(connection_t *ap_conn, circuit_t *circ) {
cell_t cell;
memset(&cell, 0, sizeof(cell_t));
/* deliver the dest_addr in a relay cell */
cell.command = CELL_RELAY;
cell.aci = circ->n_aci;
SET_CELL_RELAY_COMMAND(cell, RELAY_COMMAND_BEGIN);
if(crypto_pseudo_rand(STREAM_ID_SIZE, ap_conn->stream_id) < 0)
return -1;
/* FIXME check for collisions */
SET_CELL_STREAM_ID(cell, ZERO_STREAM);
memcpy(cell.payload+RELAY_HEADER_SIZE, ap_conn->stream_id, STREAM_ID_SIZE);
cell.length =
snprintf(cell.payload+RELAY_HEADER_SIZE+STREAM_ID_SIZE, CELL_PAYLOAD_SIZE-RELAY_HEADER_SIZE-STREAM_ID_SIZE,
"%s:%d", ap_conn->dest_addr, ap_conn->dest_port) +
1 + STREAM_ID_SIZE + RELAY_HEADER_SIZE;
log_fn(LOG_DEBUG,"Sending relay cell (id %d) to begin stream %d.", *(int *)(cell.payload+1),*(int *)ap_conn->stream_id);
if(circuit_deliver_relay_cell(&cell, circ, CELL_DIRECTION_OUT, ap_conn->cpath_layer) < 0) {
log_fn(LOG_DEBUG,"failed to deliver begin cell. Closing.");
return -1;
}
ap_conn->package_window = STREAMWINDOW_START;
ap_conn->deliver_window = STREAMWINDOW_START;
ap_conn->state = AP_CONN_STATE_OPEN;
log_fn(LOG_INFO,"Address/port sent, ap socket %d, n_aci %d",ap_conn->s,circ->n_aci);
return 0;
}
int ap_handshake_socks_reply(connection_t *conn, char result) {
socks4_t socks4_info;
assert(conn);
socks4_info.version = 0;
socks4_info.command = result;
socks4_info.destport[0] = socks4_info.destport[1] = 0;
socks4_info.destip[0] = socks4_info.destip[1] = socks4_info.destip[2] = socks4_info.destip[3] = 0;
if(connection_write_to_buf((char *)&socks4_info, sizeof(socks4_t), conn) < 0)
return -1;
return connection_flush_buf(conn); /* try to flush it, in case we're about to close the conn */
}
int connection_ap_create_listener(struct sockaddr_in *bindaddr) {
log_fn(LOG_DEBUG,"starting");
return connection_create_listener(bindaddr, CONN_TYPE_AP_LISTENER);
}
int connection_ap_handle_listener_read(connection_t *conn) {
log(LOG_NOTICE,"AP: Received a connection request. Waiting for socksinfo.");
return connection_handle_listener_read(conn, CONN_TYPE_AP, AP_CONN_STATE_SOCKS_WAIT);
}
/*
Local Variables:
mode:c
indent-tabs-mode:nil
c-basic-offset:2
End:
*/
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