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- /* Copyright 2001,2002,2003 Roger Dingledine, Matej Pfajfar. */
- /* See LICENSE for licensing information */
- /* $Id$ */
- #include "or.h"
- #include "tree.h"
- extern or_options_t options; /* command-line and config-file options */
- extern char *conn_state_to_string[][_CONN_TYPE_MAX+1];
- static int connection_ap_handshake_process_socks(connection_t *conn);
- static int connection_ap_handshake_attach_circuit(connection_t *conn);
- static void connection_ap_handshake_send_begin(connection_t *ap_conn, circuit_t *circ);
- static int connection_ap_handshake_socks_reply(connection_t *conn, char *reply,
- int replylen, char success);
- static int connection_exit_begin_conn(cell_t *cell, circuit_t *circ);
- static void connection_edge_consider_sending_sendme(connection_t *conn);
- static uint32_t client_dns_lookup_entry(const char *address);
- static void client_dns_set_entry(const char *address, uint32_t val);
- void relay_header_pack(char *dest, const relay_header_t *src) {
- *(uint8_t*)(dest) = src->command;
- *(uint16_t*)(dest+1) = htons(src->recognized);
- *(uint16_t*)(dest+3) = htons(src->stream_id);
- memcpy(dest+5, src->integrity, 4);
- *(uint16_t*)(dest+9) = htons(src->length);
- }
- void relay_header_unpack(relay_header_t *dest, const char *src) {
- dest->command = *(uint8_t*)(src);
- dest->recognized = ntohs(*(uint16_t*)(src+1));
- dest->stream_id = ntohs(*(uint16_t*)(src+3));
- memcpy(dest->integrity, src+5, 4);
- dest->length = ntohs(*(uint16_t*)(src+9));
- }
- int connection_edge_process_inbuf(connection_t *conn) {
- assert(conn);
- assert(conn->type == CONN_TYPE_AP || conn->type == CONN_TYPE_EXIT);
- if(conn->inbuf_reached_eof) {
- #ifdef HALF_OPEN
- /* eof reached; we're done reading, but we might want to write more. */
- conn->done_receiving = 1;
- shutdown(conn->s, 0); /* XXX check return, refactor NM */
- if (conn->done_sending) {
- if(connection_edge_end(conn, END_STREAM_REASON_DONE, conn->cpath_layer) < 0)
- log_fn(LOG_WARN,"1: I called connection_edge_end redundantly.");
- } else {
- connection_edge_send_command(conn, circuit_get_by_conn(conn), RELAY_COMMAND_END,
- NULL, 0, conn->cpath_layer);
- }
- return 0;
- #else
- /* eof reached, kill it. */
- log_fn(LOG_INFO,"conn (fd %d) reached eof. Closing.", conn->s);
- if(connection_edge_end(conn, END_STREAM_REASON_DONE, conn->cpath_layer) < 0)
- log_fn(LOG_WARN,"2: I called connection_edge_end redundantly.");
- return -1;
- #endif
- }
- switch(conn->state) {
- case AP_CONN_STATE_SOCKS_WAIT:
- if(connection_ap_handshake_process_socks(conn) < 0) {
- if(connection_edge_end(conn, END_STREAM_REASON_MISC, conn->cpath_layer) < 0)
- log_fn(LOG_WARN,"3: I called connection_edge_end redundantly.");
- return -1;
- }
- return 0;
- case AP_CONN_STATE_OPEN:
- case EXIT_CONN_STATE_OPEN:
- if(conn->package_window <= 0) {
- log_fn(LOG_WARN,"called with package_window %d. Tell Roger.", conn->package_window);
- return 0;
- }
- if(connection_edge_package_raw_inbuf(conn) < 0) {
- if(connection_edge_end(conn, END_STREAM_REASON_MISC, conn->cpath_layer) < 0)
- log_fn(LOG_WARN,"4: I called connection_edge_end redundantly.");
- return -1;
- }
- return 0;
- case EXIT_CONN_STATE_CONNECTING:
- log_fn(LOG_INFO,"text from server while in 'connecting' state at exit. Leaving it on buffer.");
- return 0;
- }
- log_fn(LOG_WARN,"Got unexpected state %d. Closing.",conn->state);
- return -1;
- }
- static char *connection_edge_end_reason(char *payload, uint16_t length) {
- if(length < 1) {
- log_fn(LOG_WARN,"End cell arrived with length 0. Should be at least 1.");
- return "MALFORMED";
- }
- if(*payload < END_STREAM_REASON_MISC || *payload > END_STREAM_REASON_DONE) {
- log_fn(LOG_WARN,"Reason for ending (%d) not recognized.",*payload);
- return "MALFORMED";
- }
- switch(*payload) {
- case END_STREAM_REASON_MISC: return "misc error";
- case END_STREAM_REASON_RESOLVEFAILED: return "resolve failed";
- case END_STREAM_REASON_CONNECTFAILED: return "connect failed";
- case END_STREAM_REASON_EXITPOLICY: return "exit policy failed";
- case END_STREAM_REASON_DESTROY: return "destroyed";
- case END_STREAM_REASON_DONE: return "closed normally";
- }
- assert(0);
- return "";
- }
- int connection_edge_end(connection_t *conn, char reason, crypt_path_t *cpath_layer) {
- char payload[5];
- int payload_len=1;
- circuit_t *circ;
- if(conn->has_sent_end) {
- log_fn(LOG_WARN,"It appears I've already sent the end. Are you calling me twice?");
- return -1;
- }
- payload[0] = reason;
- if(reason == END_STREAM_REASON_EXITPOLICY) {
- *(uint32_t *)(payload+1) = htonl(conn->addr);
- payload_len += 4;
- }
- circ = circuit_get_by_conn(conn);
- if(circ) {
- log_fn(LOG_DEBUG,"Marking conn (fd %d) and sending end.",conn->s);
- connection_edge_send_command(conn, circ, RELAY_COMMAND_END,
- payload, payload_len, cpath_layer);
- }
- conn->marked_for_close = 1;
- conn->has_sent_end = 1;
- return 0;
- }
- int connection_edge_send_command(connection_t *fromconn, circuit_t *circ, int relay_command,
- void *payload, int payload_len, crypt_path_t *cpath_layer) {
- cell_t cell;
- relay_header_t rh;
- int cell_direction;
- if(!circ) {
- log_fn(LOG_WARN,"no circ. Closing.");
- assert(fromconn);
- fromconn->marked_for_close = 1;
- return -1;
- }
- memset(&cell, 0, sizeof(cell_t));
- cell.command = CELL_RELAY;
- // if(fromconn && fromconn->type == CONN_TYPE_AP) {
- if(cpath_layer) {
- cell.circ_id = circ->n_circ_id;
- cell_direction = CELL_DIRECTION_OUT;
- } else {
- cell.circ_id = circ->p_circ_id;
- cell_direction = CELL_DIRECTION_IN;
- }
- memset(&rh, 0, sizeof(rh));
- rh.command = relay_command;
- if(fromconn)
- rh.stream_id = fromconn->stream_id; /* else it's 0 */
- rh.length = payload_len;
- relay_header_pack(cell.payload, &rh);
- if(payload_len)
- memcpy(cell.payload+RELAY_HEADER_SIZE, payload, payload_len);
- log_fn(LOG_DEBUG,"delivering %d cell %s.", relay_command,
- cell_direction == CELL_DIRECTION_OUT ? "forward" : "backward");
- if(circuit_package_relay_cell(&cell, circ, cell_direction, cpath_layer) < 0) {
- log_fn(LOG_WARN,"circuit_package_relay_cell failed. Closing.");
- circuit_close(circ);
- return -1;
- }
- return 0;
- }
- /* an incoming relay cell has arrived. return -1 if you want to tear down the
- * circuit, else 0. */
- int connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ, connection_t *conn,
- int edge_type, crypt_path_t *layer_hint) {
- static int num_seen=0;
- uint32_t addr;
- relay_header_t rh;
- assert(cell && circ);
- relay_header_unpack(&rh, cell->payload);
- // log_fn(LOG_DEBUG,"command %d stream %d", rh.command, rh.stream_id);
- num_seen++;
- log_fn(LOG_DEBUG,"Now seen %d relay cells here.", num_seen);
- /* either conn is NULL, in which case we've got a control cell, or else
- * conn points to the recognized stream. */
- if(conn && conn->state != AP_CONN_STATE_OPEN && conn->state != EXIT_CONN_STATE_OPEN) {
- if(rh.command == RELAY_COMMAND_END) {
- log_fn(LOG_INFO,"Exit got end (%s) before we're connected. Marking for close.",
- connection_edge_end_reason(cell->payload+RELAY_HEADER_SIZE, rh.length));
- if(conn->state == EXIT_CONN_STATE_RESOLVING) {
- log_fn(LOG_INFO,"...and informing resolver we don't want the answer anymore.");
- dns_cancel_pending_resolve(conn->address, conn);
- }
- conn->marked_for_close = 1;
- conn->has_sent_end = 1;
- return 0;
- }
- if(conn->type == CONN_TYPE_AP && rh.command == RELAY_COMMAND_CONNECTED) {
- if(conn->state != AP_CONN_STATE_CONNECTING) {
- log_fn(LOG_WARN,"Got 'connected' while not in state connecting. Dropping.");
- return 0;
- }
- log_fn(LOG_INFO,"Connected! Notifying application.");
- conn->state = AP_CONN_STATE_OPEN;
- if (rh.length >= 4) {
- addr = ntohl(*(uint32_t*)(cell->payload + RELAY_HEADER_SIZE));
- client_dns_set_entry(conn->socks_request->address, addr);
- }
- log_fn(LOG_WARN,"'connected' received after %d seconds.",
- (int)(time(NULL) - conn->timestamp_lastread));
- circuit_log_path(LOG_WARN,circ);
- if(connection_ap_handshake_socks_reply(conn, NULL, 0, 1) < 0) {
- log_fn(LOG_INFO,"Writing to socks-speaking application failed. Closing.");
- if(connection_edge_end(conn, END_STREAM_REASON_MISC, conn->cpath_layer) < 0)
- log_fn(LOG_WARN,"3: I called connection_edge_end redundantly.");
- }
- return 0;
- } else {
- log_fn(LOG_WARN,"Got an unexpected relay command %d, in state %d (%s). Closing.",
- rh.command, conn->state, conn_state_to_string[conn->type][conn->state]);
- if(connection_edge_end(conn, END_STREAM_REASON_MISC, conn->cpath_layer) < 0)
- log_fn(LOG_WARN,"1: I called connection_edge_end redundantly.");
- return -1;
- }
- }
- switch(rh.command) {
- case RELAY_COMMAND_DROP:
- log_fn(LOG_INFO,"Got a relay-level padding cell. Dropping.");
- return 0;
- case RELAY_COMMAND_BEGIN:
- if(edge_type == EDGE_AP) {
- log_fn(LOG_WARN,"relay begin request unsupported at AP. Dropping.");
- return 0;
- }
- if(conn) {
- log_fn(LOG_WARN,"begin cell for known stream. Dropping.");
- return 0;
- }
- connection_exit_begin_conn(cell, circ);
- return 0;
- case RELAY_COMMAND_DATA:
- ++stats_n_data_cells_received;
- if((edge_type == EDGE_AP && --layer_hint->deliver_window < 0) ||
- (edge_type == EDGE_EXIT && --circ->deliver_window < 0)) {
- log_fn(LOG_WARN,"(relay data) circ deliver_window below 0. Killing.");
- if(connection_edge_end(conn, END_STREAM_REASON_MISC, conn->cpath_layer) < 0)
- log_fn(LOG_WARN,"2: I called connection_edge_end redundantly.");
- return -1;
- }
- log_fn(LOG_DEBUG,"circ deliver_window now %d.", edge_type == EDGE_AP ?
- layer_hint->deliver_window : circ->deliver_window);
- circuit_consider_sending_sendme(circ, edge_type, layer_hint);
- if(!conn) {
- log_fn(LOG_INFO,"data cell dropped, unknown stream.");
- return 0;
- }
- if(--conn->deliver_window < 0) { /* is it below 0 after decrement? */
- log_fn(LOG_WARN,"(relay data) conn deliver_window below 0. Killing.");
- return -1; /* somebody's breaking protocol. kill the whole circuit. */
- }
- stats_n_data_bytes_received += rh.length;
- connection_write_to_buf(cell->payload + RELAY_HEADER_SIZE,
- rh.length, conn);
- connection_edge_consider_sending_sendme(conn);
- return 0;
- case RELAY_COMMAND_END:
- if(!conn) {
- log_fn(LOG_INFO,"end cell (%s) dropped, unknown stream.",
- connection_edge_end_reason(cell->payload+RELAY_HEADER_SIZE, rh.length));
- return 0;
- }
- if(rh.length >= 5 &&
- *(cell->payload+RELAY_HEADER_SIZE) == END_STREAM_REASON_EXITPOLICY) {
- /* No need to close the connection. We'll hold it open while
- * we try a new exit node.
- * cell->payload+RELAY_HEADER_SIZE+1 holds the destination addr.
- */
- addr = ntohl(*(uint32_t*)(cell->payload+RELAY_HEADER_SIZE+1));
- client_dns_set_entry(conn->socks_request->address, addr);
- conn->state = AP_CONN_STATE_CIRCUIT_WAIT;
- switch(connection_ap_handshake_attach_circuit(conn)) {
- case -1: /* it will never work */
- break; /* conn will get closed below */
- case 0: /* no useful circuits available */
- if(!circuit_get_newest(conn, 0)) /* is one already on the way? */
- circuit_launch_new();
- return 0;
- case 1: /* it succeeded, great */
- return 0;
- }
- }
- /* XXX add to this log_fn the exit node's nickname? */
- log_fn(LOG_INFO,"end cell (%s) for stream %d. Removing stream.",
- connection_edge_end_reason(cell->payload+RELAY_HEADER_SIZE, rh.length),
- conn->stream_id);
- #ifdef HALF_OPEN
- conn->done_sending = 1;
- shutdown(conn->s, 1); /* XXX check return; refactor NM */
- if (conn->done_receiving) {
- conn->marked_for_close = 1;
- conn->has_sent_end = 1; /* no need to send end, we just got one! */
- }
- #else
- conn->marked_for_close = 1;
- conn->has_sent_end = 1; /* no need to send end, we just got one! */
- #endif
- return 0;
- case RELAY_COMMAND_EXTEND:
- if(conn) {
- log_fn(LOG_WARN,"'extend' for non-zero stream. Dropping.");
- return 0;
- }
- return circuit_extend(cell, circ);
- case RELAY_COMMAND_EXTENDED:
- if(edge_type == EDGE_EXIT) {
- log_fn(LOG_WARN,"'extended' unsupported at exit. Dropping.");
- return 0;
- }
- log_fn(LOG_DEBUG,"Got an extended cell! Yay.");
- if(circuit_finish_handshake(circ, cell->payload+RELAY_HEADER_SIZE) < 0) {
- log_fn(LOG_WARN,"circuit_finish_handshake failed.");
- return -1;
- }
- if (circuit_send_next_onion_skin(circ)<0) {
- log_fn(LOG_INFO,"circuit_send_next_onion_skin() failed.");
- return -1;
- }
- return 0;
- case RELAY_COMMAND_TRUNCATE:
- if(edge_type == EDGE_AP) {
- log_fn(LOG_WARN,"'truncate' unsupported at AP. Dropping.");
- return 0;
- }
- if(circ->n_conn) {
- connection_send_destroy(circ->n_circ_id, circ->n_conn);
- circ->n_conn = NULL;
- }
- log_fn(LOG_DEBUG, "Processed 'truncate', replying.");
- connection_edge_send_command(NULL, circ, RELAY_COMMAND_TRUNCATED,
- NULL, 0, NULL);
- return 0;
- case RELAY_COMMAND_TRUNCATED:
- if(edge_type == EDGE_EXIT) {
- log_fn(LOG_WARN,"'truncated' unsupported at exit. Dropping.");
- return 0;
- }
- circuit_truncated(circ, layer_hint);
- return 0;
- case RELAY_COMMAND_CONNECTED:
- log_fn(LOG_WARN,"'connected' unsupported while open. Closing.");
- return -1;
- case RELAY_COMMAND_SENDME:
- if(!conn) {
- if(edge_type == EDGE_AP) {
- assert(layer_hint);
- layer_hint->package_window += CIRCWINDOW_INCREMENT;
- log_fn(LOG_DEBUG,"circ-level sendme at AP, packagewindow %d.",
- layer_hint->package_window);
- circuit_resume_edge_reading(circ, EDGE_AP, layer_hint);
- } else {
- assert(!layer_hint);
- circ->package_window += CIRCWINDOW_INCREMENT;
- log_fn(LOG_DEBUG,"circ-level sendme at exit, packagewindow %d.",
- circ->package_window);
- circuit_resume_edge_reading(circ, EDGE_EXIT, layer_hint);
- }
- return 0;
- }
- conn->package_window += STREAMWINDOW_INCREMENT;
- log_fn(LOG_DEBUG,"stream-level sendme, packagewindow now %d.", conn->package_window);
- connection_start_reading(conn);
- connection_edge_package_raw_inbuf(conn); /* handle whatever might still be on the inbuf */
- return 0;
- }
- log_fn(LOG_WARN,"unknown relay command %d.",rh.command);
- return -1;
- }
- int connection_edge_finished_flushing(connection_t *conn) {
- unsigned char connected_payload[4];
- int e, len=sizeof(e);
- assert(conn);
- assert(conn->type == CONN_TYPE_AP || conn->type == CONN_TYPE_EXIT);
- switch(conn->state) {
- case EXIT_CONN_STATE_CONNECTING:
- if (getsockopt(conn->s, SOL_SOCKET, SO_ERROR, (void*)&e, &len) < 0) { /* not yet */
- if(!ERRNO_CONN_EINPROGRESS(errno)) {
- /* yuck. kill it. */
- log_fn(LOG_DEBUG,"in-progress exit connect failed. Removing.");
- return -1;
- } else {
- log_fn(LOG_DEBUG,"in-progress exit connect still waiting.");
- return 0; /* no change, see if next time is better */
- }
- }
- /* the connect has finished. */
- log_fn(LOG_INFO,"Exit connection to %s:%u established.",
- conn->address,conn->port);
- conn->state = EXIT_CONN_STATE_OPEN;
- connection_watch_events(conn, POLLIN); /* stop writing, continue reading */
- if(connection_wants_to_flush(conn)) /* in case there are any queued relay cells */
- connection_start_writing(conn);
- /* deliver a 'connected' relay cell back through the circuit. */
- *(uint32_t*)connected_payload = htonl(conn->addr);
- if(connection_edge_send_command(conn, circuit_get_by_conn(conn),
- RELAY_COMMAND_CONNECTED, NULL, 0, NULL) < 0)
- return 0; /* circuit is closed, don't continue */
- assert(conn->package_window > 0);
- return connection_edge_process_inbuf(conn); /* in case the server has written anything */
- case AP_CONN_STATE_OPEN:
- case EXIT_CONN_STATE_OPEN:
- connection_stop_writing(conn);
- connection_edge_consider_sending_sendme(conn);
- return 0;
- case AP_CONN_STATE_SOCKS_WAIT:
- case AP_CONN_STATE_CIRCUIT_WAIT:
- connection_stop_writing(conn);
- return 0;
- default:
- log_fn(LOG_WARN,"BUG: called in unexpected state: %d", conn->state);
- return -1;
- }
- return 0;
- }
- uint64_t stats_n_data_cells_packaged = 0;
- uint64_t stats_n_data_bytes_packaged = 0;
- uint64_t stats_n_data_cells_received = 0;
- uint64_t stats_n_data_bytes_received = 0;
- int connection_edge_package_raw_inbuf(connection_t *conn) {
- int amount_to_process, length;
- char payload[CELL_PAYLOAD_SIZE];
- circuit_t *circ;
- assert(conn);
- assert(!connection_speaks_cells(conn));
- repeat_connection_edge_package_raw_inbuf:
- circ = circuit_get_by_conn(conn);
- if(!circ) {
- log_fn(LOG_INFO,"conn has no circuits! Closing.");
- return -1;
- }
- if(circuit_consider_stop_edge_reading(circ, conn->type, conn->cpath_layer))
- return 0;
- if(conn->package_window <= 0) {
- log_fn(LOG_WARN,"called with package_window %d. Tell Roger.", conn->package_window);
- connection_stop_reading(conn);
- return 0;
- }
- amount_to_process = buf_datalen(conn->inbuf);
- if(!amount_to_process)
- return 0;
- if(amount_to_process > RELAY_PAYLOAD_SIZE) {
- length = RELAY_PAYLOAD_SIZE;
- } else {
- length = amount_to_process;
- }
- stats_n_data_bytes_packaged += length;
- stats_n_data_cells_packaged += 1;
- connection_fetch_from_buf(payload, length, conn);
- log_fn(LOG_DEBUG,"(%d) Packaging %d bytes (%d waiting).", conn->s, length,
- (int)buf_datalen(conn->inbuf));
- if(connection_edge_send_command(conn, circ, RELAY_COMMAND_DATA,
- payload, length, conn->cpath_layer) < 0)
- return 0; /* circuit is closed, don't continue */
- if(conn->type == CONN_TYPE_EXIT) {
- assert(circ->package_window > 0);
- circ->package_window--;
- } else { /* we're an AP */
- assert(conn->type == CONN_TYPE_AP);
- assert(conn->cpath_layer->package_window > 0);
- conn->cpath_layer->package_window--;
- }
- if(--conn->package_window <= 0) { /* is it 0 after decrement? */
- connection_stop_reading(conn);
- log_fn(LOG_DEBUG,"conn->package_window reached 0.");
- circuit_consider_stop_edge_reading(circ, conn->type, conn->cpath_layer);
- return 0; /* don't process the inbuf any more */
- }
- log_fn(LOG_DEBUG,"conn->package_window is now %d",conn->package_window);
- /* handle more if there's more, or return 0 if there isn't */
- goto repeat_connection_edge_package_raw_inbuf;
- }
- void connection_ap_expire_beginning(void) {
- connection_t **carray;
- connection_t *conn;
- int n, i;
- time_t now = time(NULL);
- get_connection_array(&carray, &n);
- for (i = 0; i < n; ++i) {
- conn = carray[i];
- if (conn->type != CONN_TYPE_AP ||
- conn->state != AP_CONN_STATE_CONNECTING)
- continue;
- if (now - conn->timestamp_lastread > 30) {
- log_fn(LOG_WARN,"Stream is %d seconds late. Closing.",
- (int)(now - conn->timestamp_lastread));
- /* XXX here is where it should move back into 'pending' state */
- conn->marked_for_close = 1;
- }
- }
- }
- /* Tell any APs that are waiting for a new circuit that one is available */
- void connection_ap_attach_pending(void)
- {
- connection_t **carray;
- connection_t *conn;
- int n, i;
- get_connection_array(&carray, &n);
- for (i = 0; i < n; ++i) {
- conn = carray[i];
- if (conn->type != CONN_TYPE_AP ||
- conn->state != AP_CONN_STATE_CIRCUIT_WAIT)
- continue;
- switch(connection_ap_handshake_attach_circuit(conn)) {
- case -1: /* it will never work */
- conn->marked_for_close = 1;
- conn->has_sent_end = 1;
- break;
- case 0: /* we need to build another circuit */
- if(!circuit_get_newest(conn, 0)) {
- /* if there are no acceptable clean or not-very-dirty circs on the way */
- circuit_launch_new();
- }
- break;
- case 1: /* it succeeded, great */
- break;
- }
- }
- }
- static void connection_edge_consider_sending_sendme(connection_t *conn) {
- circuit_t *circ;
- if(connection_outbuf_too_full(conn))
- return;
- circ = circuit_get_by_conn(conn);
- if(!circ) {
- /* this can legitimately happen if the destroy has already
- * arrived and torn down the circuit */
- log_fn(LOG_INFO,"No circuit associated with conn. Skipping.");
- return;
- }
- while(conn->deliver_window < STREAMWINDOW_START - STREAMWINDOW_INCREMENT) {
- log_fn(LOG_DEBUG,"Outbuf %d, Queueing stream sendme.", conn->outbuf_flushlen);
- conn->deliver_window += STREAMWINDOW_INCREMENT;
- if(connection_edge_send_command(conn, circ, RELAY_COMMAND_SENDME,
- NULL, 0, conn->cpath_layer) < 0) {
- log_fn(LOG_WARN,"connection_edge_send_command failed. Returning.");
- return; /* the circuit's closed, don't continue */
- }
- }
- }
- static int connection_ap_handshake_process_socks(connection_t *conn) {
- socks_request_t *socks;
- int sockshere;
- assert(conn);
- assert(conn->type == CONN_TYPE_AP);
- assert(conn->state == AP_CONN_STATE_SOCKS_WAIT);
- assert(conn->socks_request);
- socks = conn->socks_request;
- log_fn(LOG_DEBUG,"entered.");
- sockshere = fetch_from_buf_socks(conn->inbuf, socks);
- if(sockshere == -1 || sockshere == 0) {
- if(socks->replylen) { /* we should send reply back */
- log_fn(LOG_DEBUG,"reply is already set for us. Using it.");
- connection_ap_handshake_socks_reply(conn, socks->reply, socks->replylen, 0);
- } else if(sockshere == -1) { /* send normal reject */
- log_fn(LOG_WARN,"Fetching socks handshake failed. Closing.");
- connection_ap_handshake_socks_reply(conn, NULL, 0, 0);
- } else {
- log_fn(LOG_DEBUG,"socks handshake not all here yet.");
- }
- return sockshere;
- } /* else socks handshake is done, continue processing */
- conn->state = AP_CONN_STATE_CIRCUIT_WAIT;
- switch(connection_ap_handshake_attach_circuit(conn)) {
- case -1: /* it will never work */
- return -1;
- case 0: /* no useful circuits available */
- if(!circuit_get_newest(conn, 0)) /* is one already on the way? */
- circuit_launch_new();
- break;
- case 1: /* it succeeded, great */
- break;
- }
- return 0;
- }
- /* Try to find a safe live circuit for CONN_TYPE_AP connection conn. If
- * we don't find one: if conn cannot be handled by any known nodes,
- * warn and return -1; else tell conn to stop reading and return 0.
- * Otherwise, associate conn with a safe live circuit, start
- * sending a BEGIN cell down the circuit, and return 1.
- */
- static int connection_ap_handshake_attach_circuit(connection_t *conn) {
- circuit_t *circ;
- uint32_t addr;
- assert(conn);
- assert(conn->type == CONN_TYPE_AP);
- assert(conn->state == AP_CONN_STATE_CIRCUIT_WAIT);
- assert(conn->socks_request);
- /* find the circuit that we should use, if there is one. */
- circ = circuit_get_newest(conn, 1);
- if(!circ) {
- log_fn(LOG_INFO,"No safe circuit ready for edge connection; delaying.");
- addr = client_dns_lookup_entry(conn->socks_request->address);
- if(router_exit_policy_all_routers_reject(addr, conn->socks_request->port)) {
- log_fn(LOG_WARN,"No node exists that will handle exit to %s:%d. Rejecting.",
- conn->socks_request->address, conn->socks_request->port);
- return -1;
- }
- connection_stop_reading(conn); /* don't read until the connected cell arrives */
- return 0;
- }
- connection_start_reading(conn);
- /* here, print the circ's path. so people can figure out which circs are sucking. */
- circuit_log_path(LOG_WARN,circ);
- if(!circ->timestamp_dirty)
- circ->timestamp_dirty = time(NULL);
- /* add it into the linked list of streams on this circuit */
- log_fn(LOG_DEBUG,"attaching new conn to circ. n_circ_id %d.", circ->n_circ_id);
- conn->next_stream = circ->p_streams;
- /* assert_connection_ok(conn, time(NULL)); */
- circ->p_streams = conn;
- assert(circ->cpath && circ->cpath->prev);
- assert(circ->cpath->prev->state == CPATH_STATE_OPEN);
- conn->cpath_layer = circ->cpath->prev;
- connection_ap_handshake_send_begin(conn, circ);
- return 1;
- }
- /* Iterate over the two bytes of stream_id until we get one that is not
- * already in use. Return 0 if can't get a unique stream_id.
- */
- static uint16_t get_unique_stream_id_by_circ(circuit_t *circ) {
- connection_t *tmpconn;
- uint16_t test_stream_id;
- uint32_t attempts=0;
- again:
- test_stream_id = circ->next_stream_id++;
- if(++attempts > 1<<16) {
- /* Make sure we don't loop forever if all stream_id's are used. */
- log_fn(LOG_WARN,"No unused stream IDs. Failing.");
- return 0;
- }
- if (test_stream_id == 0)
- goto again;
- for(tmpconn = circ->p_streams; tmpconn; tmpconn=tmpconn->next_stream)
- if(tmpconn->stream_id == test_stream_id)
- goto again;
- return test_stream_id;
- }
- /* deliver the destaddr:destport in a relay cell */
- static void connection_ap_handshake_send_begin(connection_t *ap_conn, circuit_t *circ)
- {
- char payload[CELL_PAYLOAD_SIZE];
- int payload_len;
- struct in_addr in;
- const char *string_addr;
- assert(ap_conn->type == CONN_TYPE_AP);
- assert(ap_conn->state == AP_CONN_STATE_CIRCUIT_WAIT);
- assert(ap_conn->socks_request);
- ap_conn->stream_id = get_unique_stream_id_by_circ(circ);
- if (ap_conn->stream_id==0) {
- ap_conn->marked_for_close = 1;
- return;
- }
- in.s_addr = htonl(client_dns_lookup_entry(ap_conn->socks_request->address));
- string_addr = in.s_addr ? inet_ntoa(in) : NULL;
- snprintf(payload,RELAY_PAYLOAD_SIZE,
- "%s:%d",
- string_addr ? string_addr : ap_conn->socks_request->address,
- ap_conn->socks_request->port);
- payload_len = strlen(payload)+1;
- log_fn(LOG_DEBUG,"Sending relay cell to begin stream %d.",ap_conn->stream_id);
- if(connection_edge_send_command(ap_conn, circ, RELAY_COMMAND_BEGIN,
- payload, payload_len, ap_conn->cpath_layer) < 0)
- return; /* circuit is closed, don't continue */
- ap_conn->package_window = STREAMWINDOW_START;
- ap_conn->deliver_window = STREAMWINDOW_START;
- ap_conn->state = AP_CONN_STATE_CONNECTING;
- /* XXX Right now, we rely on the socks client not to send us any data
- * XXX until we've sent back a socks reply. (If it does, we could wind
- * XXX up packaging that data and sending it to the exit, then later having
- * XXX the exit refuse us.)
- */
- log_fn(LOG_INFO,"Address/port sent, ap socket %d, n_circ_id %d",ap_conn->s,circ->n_circ_id);
- return;
- }
- static int connection_ap_handshake_socks_reply(connection_t *conn, char *reply,
- int replylen, char success) {
- char buf[256];
- if(replylen) { /* we already have a reply in mind */
- connection_write_to_buf(reply, replylen, conn);
- return flush_buf(conn->s, conn->outbuf, &conn->outbuf_flushlen); /* try to flush it */
- }
- assert(conn->socks_request);
- if(conn->socks_request->socks_version == 4) {
- memset(buf,0,SOCKS4_NETWORK_LEN);
- #define SOCKS4_GRANTED 90
- #define SOCKS4_REJECT 91
- buf[1] = (success ? SOCKS4_GRANTED : SOCKS4_REJECT);
- /* leave version, destport, destip zero */
- connection_write_to_buf(buf, SOCKS4_NETWORK_LEN, conn);
- return flush_buf(conn->s, conn->outbuf, &conn->outbuf_flushlen); /* try to flush it */
- }
- if(conn->socks_request->socks_version == 5) {
- buf[0] = 5; /* version 5 */
- #define SOCKS5_SUCCESS 0
- #define SOCKS5_GENERIC_ERROR 1
- buf[1] = success ? SOCKS5_SUCCESS : SOCKS5_GENERIC_ERROR;
- buf[2] = 0;
- buf[3] = 1; /* ipv4 addr */
- memset(buf+4,0,6); /* Set external addr/port to 0.
- The spec doesn't seem to say what to do here. -RD */
- connection_write_to_buf(buf,10,conn);
- return flush_buf(conn->s, conn->outbuf, &conn->outbuf_flushlen); /* try to flush it */
- }
- return 0; /* if socks_version isn't 4 or 5, don't send anything */
- }
- static int connection_exit_begin_conn(cell_t *cell, circuit_t *circ) {
- connection_t *n_stream;
- relay_header_t rh;
- char *colon;
- relay_header_unpack(&rh, cell->payload);
- /* XXX currently we don't send an end cell back if we drop the
- * begin because it's malformed.
- */
- if(!memchr(cell->payload+RELAY_HEADER_SIZE, 0, rh.length)) {
- log_fn(LOG_WARN,"relay begin cell has no \\0. Dropping.");
- return 0;
- }
- colon = strchr(cell->payload+RELAY_HEADER_SIZE, ':');
- if(!colon) {
- log_fn(LOG_WARN,"relay begin cell has no colon. Dropping.");
- return 0;
- }
- *colon = 0;
- if(!atoi(colon+1)) { /* bad port */
- log_fn(LOG_WARN,"relay begin cell has invalid port. Dropping.");
- return 0;
- }
- log_fn(LOG_DEBUG,"Creating new exit connection.");
- n_stream = connection_new(CONN_TYPE_EXIT);
- n_stream->stream_id = rh.stream_id;
- n_stream->address = tor_strdup(cell->payload + RELAY_HEADER_SIZE);
- n_stream->port = atoi(colon+1);
- n_stream->state = EXIT_CONN_STATE_RESOLVING;
- /* leave n_stream->s at -1, because it's 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_WARN,"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 */
- connection_exit_connect(n_stream);
- return 0;
- case -1: /* resolve failed */
- log_fn(LOG_INFO,"Resolve failed (%s).", n_stream->address);
- if(connection_edge_end(n_stream, END_STREAM_REASON_RESOLVEFAILED, NULL) < 0)
- log_fn(LOG_WARN,"1: I called connection_edge_end redundantly.");
- /* case 0, resolve added to pending list */
- }
- return 0;
- }
- void connection_exit_connect(connection_t *conn) {
- unsigned char connected_payload[4];
- if(router_compare_to_my_exit_policy(conn) < 0) {
- log_fn(LOG_INFO,"%s:%d failed exit policy. Closing.", conn->address, conn->port);
- if(connection_edge_end(conn, END_STREAM_REASON_EXITPOLICY, NULL) < 0)
- log_fn(LOG_WARN,"1: I called connection_edge_end redundantly.");
- return;
- }
- switch(connection_connect(conn, conn->address, conn->addr, conn->port)) {
- case -1:
- if(connection_edge_end(conn, END_STREAM_REASON_CONNECTFAILED, NULL) < 0)
- log_fn(LOG_WARN,"2: I called connection_edge_end redundantly.");
- return;
- case 0:
- connection_set_poll_socket(conn);
- conn->state = EXIT_CONN_STATE_CONNECTING;
- connection_watch_events(conn, POLLOUT | POLLIN | POLLERR);
- /* writable indicates finish, readable indicates broken link,
- error indicates broken link in windowsland. */
- return;
- /* case 1: fall through */
- }
- 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_WARN,"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. */
- *((uint32_t*) connected_payload) = htonl(conn->addr);
- connection_edge_send_command(conn, circuit_get_by_conn(conn), RELAY_COMMAND_CONNECTED,
- connected_payload, 4, NULL);
- }
- int connection_ap_can_use_exit(connection_t *conn, routerinfo_t *exit)
- {
- uint32_t addr;
- assert(conn);
- assert(conn->type == CONN_TYPE_AP);
- assert(conn->socks_request);
- log_fn(LOG_DEBUG,"considering nickname %s, for address %s / port %d:",
- exit->nickname, conn->socks_request->address,
- conn->socks_request->port);
- addr = client_dns_lookup_entry(conn->socks_request->address);
- return router_compare_addr_to_exit_policy(addr,
- conn->socks_request->port, exit->exit_policy);
- }
- /* ***** Client DNS code ***** */
- /* XXX Perhaps this should get merged with the dns.c code somehow. */
- /* XXX But we can't just merge them, because then nodes that act as
- * both OR and OP could be attacked: people could rig the dns cache
- * by answering funny things to stream begin requests, and later
- * other clients would reuse those funny addr's. Hm.
- */
- struct client_dns_entry {
- SPLAY_ENTRY(client_dns_entry) node;
- char *address;
- uint32_t addr;
- time_t expires;
- };
- static int client_dns_size = 0;
- static SPLAY_HEAD(client_dns_tree, client_dns_entry) client_dns_root;
- static int compare_client_dns_entries(struct client_dns_entry *a,
- struct client_dns_entry *b)
- {
- return strcasecmp(a->address, b->address);
- }
- static void client_dns_entry_free(struct client_dns_entry *ent)
- {
- tor_free(ent->address);
- tor_free(ent);
- }
- SPLAY_PROTOTYPE(client_dns_tree, client_dns_entry, node, compare_client_dns_entries);
- SPLAY_GENERATE(client_dns_tree, client_dns_entry, node, compare_client_dns_entries);
- void client_dns_init(void) {
- SPLAY_INIT(&client_dns_root);
- client_dns_size = 0;
- }
- static uint32_t client_dns_lookup_entry(const char *address)
- {
- struct client_dns_entry *ent;
- struct client_dns_entry search;
- struct in_addr in;
- time_t now;
- assert(address);
- if (inet_aton(address, &in)) {
- log_fn(LOG_DEBUG, "Using static address %s (%08lX)", address,
- (unsigned long)ntohl(in.s_addr));
- return ntohl(in.s_addr);
- }
- search.address = (char*)address;
- ent = SPLAY_FIND(client_dns_tree, &client_dns_root, &search);
- if (!ent) {
- log_fn(LOG_DEBUG, "No entry found for address %s", address);
- return 0;
- } else {
- now = time(NULL);
- if (ent->expires < now) {
- log_fn(LOG_DEBUG, "Expired entry found for address %s", address);
- SPLAY_REMOVE(client_dns_tree, &client_dns_root, ent);
- client_dns_entry_free(ent);
- --client_dns_size;
- return 0;
- }
- in.s_addr = htonl(ent->addr);
- log_fn(LOG_DEBUG, "Found cached entry for address %s: %s", address,
- inet_ntoa(in));
- return ent->addr;
- }
- }
- static void client_dns_set_entry(const char *address, uint32_t val)
- {
- struct client_dns_entry *ent;
- struct client_dns_entry search;
- struct in_addr in;
- time_t now;
- assert(address);
- assert(val);
- if (inet_aton(address, &in))
- return;
- search.address = (char*) address;
- now = time(NULL);
- ent = SPLAY_FIND(client_dns_tree, &client_dns_root, &search);
- if (ent) {
- in.s_addr = htonl(val);
- log_fn(LOG_DEBUG, "Updating entry for address %s: %s", address,
- inet_ntoa(in));
- ent->addr = val;
- ent->expires = now+MAX_DNS_ENTRY_AGE;
- } else {
- in.s_addr = htonl(val);
- log_fn(LOG_DEBUG, "Caching result for address %s: %s", address,
- inet_ntoa(in));
- ent = tor_malloc(sizeof(struct client_dns_entry));
- ent->address = tor_strdup(address);
- ent->addr = val;
- ent->expires = now+MAX_DNS_ENTRY_AGE;
- SPLAY_INSERT(client_dns_tree, &client_dns_root, ent);
- ++client_dns_size;
- }
- }
- void client_dns_clean(void)
- {
- struct client_dns_entry **expired_entries;
- int n_expired_entries = 0;
- struct client_dns_entry *ent;
- time_t now;
- int i;
- if(!client_dns_size)
- return;
- expired_entries = tor_malloc(client_dns_size *
- sizeof(struct client_dns_entry *));
- now = time(NULL);
- SPLAY_FOREACH(ent, client_dns_tree, &client_dns_root) {
- if (ent->expires < now) {
- expired_entries[n_expired_entries++] = ent;
- }
- }
- for (i = 0; i < n_expired_entries; ++i) {
- SPLAY_REMOVE(client_dns_tree, &client_dns_root, expired_entries[i]);
- client_dns_entry_free(expired_entries[i]);
- }
- tor_free(expired_entries);
- }
- /*
- Local Variables:
- mode:c
- indent-tabs-mode:nil
- c-basic-offset:2
- End:
- */
|