/* Copyright (c) 2001 Matej Pfajfar.
* Copyright (c) 2001-2004, Roger Dingledine.
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. */
/* See LICENSE for licensing information */
/* $Id$ */
const char connection_or_c_id[] =
"$Id$";
/**
* \file connection_or.c
* \brief Functions to handle OR connections, TLS handshaking, and
* cells on the network.
**/
#include "or.h"
/** How much clock skew do we tolerate when checking certificates for
* known routers? (sec) */
#define TIGHT_CERT_ALLOW_SKEW (90*60)
static int connection_tls_finish_handshake(connection_t *conn);
static int connection_or_process_cells_from_inbuf(connection_t *conn);
/**************************************************************/
/** Map from identity digest of connected OR or desired OR to a connection_t
* with that identity digest. If there is more than one such connection_t,
* they form a linked list, with next_with_same_id as the next pointer.*/
static digestmap_t *orconn_identity_map = NULL;
/** If conn is listed in orconn_identity_map, remove it, and clear
* conn->identity_digest. */
void
connection_or_remove_from_identity_map(connection_t *conn)
{
connection_t *tmp;
tor_assert(conn);
tor_assert(conn->type == CONN_TYPE_OR);
if (!orconn_identity_map)
return;
tmp = digestmap_get(orconn_identity_map, conn->identity_digest);
if (!tmp)
return;
if (conn == tmp) {
if (conn->next_with_same_id)
digestmap_set(orconn_identity_map, conn->identity_digest,
conn->next_with_same_id);
else
digestmap_remove(orconn_identity_map, conn->identity_digest);
} else {
while (tmp->next_with_same_id) {
if (tmp->next_with_same_id == conn) {
tmp->next_with_same_id = conn->next_with_same_id;
break;
}
tmp = tmp->next_with_same_id;
}
}
memset(conn->identity_digest, 0, DIGEST_LEN);
conn->next_with_same_id = NULL;
}
/** Remove all entries from the identity-to-orconn map, and clear
* all identities in OR conns.*/
void
connection_or_clear_identity_map(void)
{
int i, n;
connection_t **carray;
get_connection_array(&carray,&n);
for (i = 0; i < n; ++i) {
connection_t* conn = carray[i];
if (conn->type == CONN_TYPE_OR) {
memset(conn->identity_digest, 0, DIGEST_LEN);
conn->next_with_same_id = NULL;
}
}
if (orconn_identity_map) {
digestmap_free(orconn_identity_map, NULL);
orconn_identity_map = NULL;
}
}
/** Change conn->identity_digest to digest, and add conn into
* orconn_digest_map. */
static void
connection_or_set_identity_digest(connection_t *conn, const char *digest)
{
connection_t *tmp;
tor_assert(conn);
tor_assert(conn->type == CONN_TYPE_OR);
tor_assert(digest);
if (!orconn_identity_map)
orconn_identity_map = digestmap_new();
if (!memcmp(conn->identity_digest, digest, DIGEST_LEN))
return;
if (tor_digest_is_zero(conn->identity_digest))
connection_or_remove_from_identity_map(conn);
memcpy(conn->identity_digest, digest, DIGEST_LEN);
tmp = digestmap_set(orconn_identity_map, digest, conn);
conn->next_with_same_id = tmp;
/* Checking code; remove once I'm sure this works. XXXX*/
for (; tmp; tmp = tmp->next_with_same_id) {
tor_assert(!memcmp(tmp->identity_digest, digest, DIGEST_LEN));
tor_assert(tmp != conn);
}
}
/** Pack the cell_t host-order structure src into network-order
* in the buffer dest. See tor-spec.txt for details about the
* wire format.
*/
static void
cell_pack(char *dest, const cell_t *src)
{
*(uint16_t*)dest = htons(src->circ_id);
*(uint8_t*)(dest+2) = src->command;
memcpy(dest+3, src->payload, CELL_PAYLOAD_SIZE);
}
/** Unpack the network-order buffer src into a host-order
* cell_t structure dest.
*/
static void
cell_unpack(cell_t *dest, const char *src)
{
dest->circ_id = ntohs(*(uint16_t*)(src));
dest->command = *(uint8_t*)(src+2);
memcpy(dest->payload, src+3, CELL_PAYLOAD_SIZE);
}
int
connection_or_reached_eof(connection_t *conn)
{
info(LD_OR,"OR connection reached EOF. Closing.");
connection_mark_for_close(conn);
return 0;
}
/** Read conn's inbuf. If the http response from the proxy is all
* here, make sure it's good news, and begin the tls handshake. If
* it's bad news, close the connection and return -1. Else return 0
* and hope for better luck next time.
*/
static int
connection_or_read_proxy_response(connection_t *conn)
{
char *headers;
char *reason=NULL;
int status_code;
time_t date_header;
int compression;
switch (fetch_from_buf_http(conn->inbuf,
&headers, MAX_HEADERS_SIZE,
NULL, NULL, 10000, 0)) {
case -1: /* overflow */
warn(LD_PROTOCOL,"Your https proxy sent back an oversized response. "
"Closing.");
return -1;
case 0:
info(LD_OR,"https proxy response not all here yet. Waiting.");
return 0;
/* case 1, fall through */
}
if (parse_http_response(headers, &status_code, &date_header,
&compression, &reason) < 0) {
warn(LD_OR,"Unparseable headers from proxy (connecting to '%s'). Closing.",
conn->address);
tor_free(headers);
return -1;
}
if (!reason) reason = tor_strdup("[no reason given]");
if (status_code == 200) {
info(LD_OR,
"HTTPS connect to '%s' successful! (200 \"%s\") Starting TLS.",
conn->address, reason);
tor_free(reason);
if (connection_tls_start_handshake(conn, 0) < 0) {
/* TLS handshaking error of some kind. */
connection_mark_for_close(conn);
return -1;
}
return 0;
}
/* else, bad news on the status code */
warn(LD_OR,
"The https proxy sent back an unexpected status code %d (\"%s\"). "
"Closing.",
status_code, reason);
tor_free(reason);
connection_mark_for_close(conn);
return -1;
}
/** Handle any new bytes that have come in on connection conn.
* If conn is in 'open' state, hand it to
* connection_or_process_cells_from_inbuf()
* (else do nothing).
*/
int
connection_or_process_inbuf(connection_t *conn)
{
tor_assert(conn);
tor_assert(conn->type == CONN_TYPE_OR);
switch (conn->state) {
case OR_CONN_STATE_PROXY_READING:
return connection_or_read_proxy_response(conn);
case OR_CONN_STATE_OPEN:
return connection_or_process_cells_from_inbuf(conn);
default:
return 0; /* don't do anything */
}
}
/** Connection conn has finished writing and has no bytes left on
* its outbuf.
*
* Otherwise it's in state "open": stop writing and return.
*
* If conn is broken, mark it for close and return -1, else
* return 0.
*/
int
connection_or_finished_flushing(connection_t *conn)
{
tor_assert(conn);
tor_assert(conn->type == CONN_TYPE_OR);
assert_connection_ok(conn,0);
switch (conn->state) {
case OR_CONN_STATE_PROXY_FLUSHING:
debug(LD_OR,"finished sending CONNECT to proxy.");
conn->state = OR_CONN_STATE_PROXY_READING;
connection_stop_writing(conn);
break;
case OR_CONN_STATE_OPEN:
connection_stop_writing(conn);
break;
default:
err(LD_BUG,"BUG: called in unexpected state %d.", conn->state);
tor_fragile_assert();
return -1;
}
return 0;
}
/** Connected handler for OR connections: begin the TLS handshake.
*/
int
connection_or_finished_connecting(connection_t *conn)
{
tor_assert(conn);
tor_assert(conn->type == CONN_TYPE_OR);
tor_assert(conn->state == OR_CONN_STATE_CONNECTING);
debug(LD_OR,"OR connect() to router at %s:%u finished.",
conn->address,conn->port);
if (get_options()->HttpsProxy) {
char buf[1024];
char addrbuf[INET_NTOA_BUF_LEN];
struct in_addr in;
char *base64_authenticator=NULL;
const char *authenticator = get_options()->HttpsProxyAuthenticator;
in.s_addr = htonl(conn->addr);
tor_inet_ntoa(&in, addrbuf, sizeof(addrbuf));
if (authenticator) {
base64_authenticator = alloc_http_authenticator(authenticator);
if (!base64_authenticator)
warn(LD_OR, "Encoding https authenticator failed");
}
if (base64_authenticator) {
tor_snprintf(buf, sizeof(buf), "CONNECT %s:%d HTTP/1.1\r\n"
"Proxy-Authorization: Basic %s\r\n\r\n", addrbuf,
conn->port, base64_authenticator);
tor_free(base64_authenticator);
} else {
tor_snprintf(buf, sizeof(buf), "CONNECT %s:%d HTTP/1.0\r\n\r\n",
addrbuf, conn->port);
}
connection_write_to_buf(buf, strlen(buf), conn);
conn->state = OR_CONN_STATE_PROXY_FLUSHING;
return 0;
}
if (connection_tls_start_handshake(conn, 0) < 0) {
/* TLS handshaking error of some kind. */
connection_mark_for_close(conn);
return -1;
}
return 0;
}
/** Initialize conn to include all the relevant data from router.
* This function is called either from connection_or_connect(), if
* we initiated the connect, or from connection_tls_finish_handshake()
* if the other side initiated it.
*/
static void
connection_or_init_conn_from_router(connection_t *conn, routerinfo_t *router)
{
or_options_t *options = get_options();
conn->addr = router->addr;
conn->port = router->or_port;
conn->receiver_bucket = conn->bandwidth = (int)options->BandwidthBurst;
conn->identity_pkey = crypto_pk_dup_key(router->identity_pkey);
connection_or_set_identity_digest(conn, router->cache_info.identity_digest);
conn->nickname = tor_strdup(router->nickname);
tor_free(conn->address);
conn->address = tor_strdup(router->address);
}
/** If we don't necessarily know the router we're connecting to, but we
* have an addr/port/id_digest, then fill in as much as we can. Start
* by checking to see if this describes a router we know. */
static void
connection_or_init_conn_from_address(connection_t *conn,
uint32_t addr, uint16_t port,
const char *id_digest)
{
const char *n;
or_options_t *options = get_options();
routerinfo_t *r = router_get_by_digest(id_digest);
if (r) {
connection_or_init_conn_from_router(conn,r);
return;
}
conn->addr = addr;
conn->port = port;
/* This next part isn't really right, but it's good enough for now. */
conn->receiver_bucket = conn->bandwidth = (int)options->BandwidthBurst;
connection_or_set_identity_digest(conn, id_digest);
/* If we're an authoritative directory server, we may know a
* nickname for this router. */
n = dirserv_get_nickname_by_digest(id_digest);
if (n) {
conn->nickname = tor_strdup(n);
} else {
conn->nickname = tor_malloc(HEX_DIGEST_LEN+2);
conn->nickname[0] = '$';
base16_encode(conn->nickname+1, HEX_DIGEST_LEN+1,
conn->identity_digest, DIGEST_LEN);
}
tor_free(conn->address);
conn->address = tor_dup_addr(addr);
}
/** Return the best connection of type OR with the
* digest digest that we have, or NULL if we have none.
*
* 1) Don't return it if it's marked for close.
* 2) If there are any open conns, ignore non-open conns.
* 3) If there are any non-obsolete conns, ignore obsolete conns.
* 4) Then if there are any non-empty conns, ignore empty conns.
* 5) Of the remaining conns, prefer newer conns.
*/
connection_t *
connection_or_get_by_identity_digest(const char *digest)
{
int newer;
connection_t *conn, *best=NULL;
if (!orconn_identity_map)
return NULL;
conn = digestmap_get(orconn_identity_map, digest);
for (; conn; conn = conn->next_with_same_id) {
tor_assert(conn->magic == CONNECTION_MAGIC);
tor_assert(conn->type == CONN_TYPE_OR);
tor_assert(!memcmp(conn->identity_digest, digest, DIGEST_LEN));
if (conn->marked_for_close)
continue;
if (!best) {
best = conn; /* whatever it is, it's better than nothing. */
continue;
}
if (best->state == OR_CONN_STATE_OPEN &&
conn->state != OR_CONN_STATE_OPEN)
continue; /* avoid non-open conns if we can */
newer = best->timestamp_created < conn->timestamp_created;
if (conn->is_obsolete && (!best->is_obsolete || !newer))
continue; /* we have something, and it's better than this. */
if (best->n_circuits && !conn->n_circuits)
continue; /* prefer conns with circuits on them */
if (newer)
best = conn; /* lastly, prefer newer conns */
}
return best;
}
/** Launch a new OR connection to addr:port and expect to
* handshake with an OR with identity digest id_digest.
*
* If id_digest is me, do nothing. If we're already connected to it,
* return that connection. If the connect() is in progress, set the
* new conn's state to 'connecting' and return it. If connect() succeeds,
* call connection_tls_start_handshake() on it.
*
* This function is called from router_retry_connections(), for
* ORs connecting to ORs, and circuit_establish_circuit(), for
* OPs connecting to ORs.
*
* Return the launched conn, or NULL if it failed.
*/
connection_t *
connection_or_connect(uint32_t addr, uint16_t port, const char *id_digest)
{
connection_t *conn;
routerinfo_t *me;
or_options_t *options = get_options();
tor_assert(id_digest);
if (server_mode(options) && (me=router_get_my_routerinfo()) &&
router_digest_is_me(id_digest)) {
info(LD_PROTOCOL,"Client asked me to connect to myself. Refusing.");
return NULL;
}
conn = connection_new(CONN_TYPE_OR);
/* set up conn so it's got all the data we need to remember */
connection_or_init_conn_from_address(conn, addr, port, id_digest);
conn->state = OR_CONN_STATE_CONNECTING;
control_event_or_conn_status(conn, OR_CONN_EVENT_LAUNCHED);
if (options->HttpsProxy) {
/* we shouldn't connect directly. use the https proxy instead. */
addr = options->HttpsProxyAddr;
port = options->HttpsProxyPort;
}
switch (connection_connect(conn, conn->address, addr, port)) {
case -1:
/* If the connection failed immediately, and we're using
* an https proxy, our https proxy is down. Don't blame the
* Tor server. */
if (!options->HttpsProxy) {
router_mark_as_down(conn->identity_digest);
entry_guard_set_status(conn->identity_digest, 0);
}
control_event_or_conn_status(conn, OR_CONN_EVENT_FAILED);
connection_free(conn);
return NULL;
case 0:
connection_watch_events(conn, EV_READ | EV_WRITE);
/* writable indicates finish, readable indicates broken link,
error indicates broken link on windows */
return conn;
/* case 1: fall through */
}
if (connection_or_finished_connecting(conn) < 0) {
/* already marked for close */
return NULL;
}
return conn;
}
/** Begin the tls handshake with conn. receiving is 0 if
* we initiated the connection, else it's 1.
*
* Assign a new tls object to conn->tls, begin reading on conn, and
* pass conn to connection_tls_continue_handshake().
*
* Return -1 if conn is broken, else return 0.
*/
int
connection_tls_start_handshake(connection_t *conn, int receiving)
{
conn->state = OR_CONN_STATE_HANDSHAKING;
conn->tls = tor_tls_new(conn->s, receiving, 0);
if (!conn->tls) {
warn(LD_BUG,"tor_tls_new failed. Closing.");
return -1;
}
connection_start_reading(conn);
debug(LD_OR,"starting TLS handshake on fd %d", conn->s);
if (connection_tls_continue_handshake(conn) < 0) {
return -1;
}
return 0;
}
/** Move forward with the tls handshake. If it finishes, hand
* conn to connection_tls_finish_handshake().
*
* Return -1 if conn is broken, else return 0.
*/
int
connection_tls_continue_handshake(connection_t *conn)
{
check_no_tls_errors();
switch (tor_tls_handshake(conn->tls)) {
case TOR_TLS_ERROR:
case TOR_TLS_CLOSE:
info(LD_OR,"tls error. breaking connection.");
return -1;
case TOR_TLS_DONE:
return connection_tls_finish_handshake(conn);
case TOR_TLS_WANTWRITE:
connection_start_writing(conn);
debug(LD_OR,"wanted write");
return 0;
case TOR_TLS_WANTREAD: /* handshaking conns are *always* reading */
debug(LD_OR,"wanted read");
return 0;
}
return 0;
}
/** Return 1 if we initiated this connection, or 0 if it started
* out as an incoming connection.
*
* This is implemented for now by checking to see if
* conn-\>identity_digest is set or not. Perhaps we should add a flag
* one day so we're clearer.
*/
int
connection_or_nonopen_was_started_here(connection_t *conn)
{
tor_assert(conn->type == CONN_TYPE_OR);
if (tor_digest_is_zero(conn->identity_digest))
return 0;
else
return 1;
}
/** Conn just completed its handshake. Return 0 if all is well, and
* return -1 if he is lying, broken, or otherwise something is wrong.
*
* Make sure he sent a correctly formed certificate. If it has a
* recognized (approved) nickname, make sure his identity key matches
* it. If I initiated the connection, make sure it's the right guy.
*
* If we return 0, write a hash of the identity key into digest_rcvd,
* which must have DIGEST_LEN space in it. (If we return -1 this
* buffer is undefined.)
*
* As side effects,
* 1) Set conn->circ_id_type according to tor-spec.txt
* 2) If we're an authdirserver and we initiated the connection: drop all
* descriptors that claim to be on that IP/port but that aren't
* this guy; and note that this guy is reachable.
*/
static int
connection_or_check_valid_handshake(connection_t *conn, char *digest_rcvd)
{
routerinfo_t *router;
crypto_pk_env_t *identity_rcvd=NULL;
char nickname[MAX_NICKNAME_LEN+1];
or_options_t *options = get_options();
int severity = server_mode(options) ? LOG_PROTOCOL_WARN : LOG_WARN;
check_no_tls_errors();
if (! tor_tls_peer_has_cert(conn->tls)) {
info(LD_PROTOCOL,"Peer didn't send a cert! Closing.");
return -1;
}
check_no_tls_errors();
if (tor_tls_get_peer_cert_nickname(conn->tls, nickname, sizeof(nickname))) {
log_fn(severity,LD_PROTOCOL,"Other side (%s:%d) has a cert without a "
"valid nickname. Closing.",
conn->address, conn->port);
return -1;
}
check_no_tls_errors();
debug(LD_OR, "Other side (%s:%d) claims to be router '%s'",
conn->address, conn->port, nickname);
if (tor_tls_verify(severity, conn->tls, &identity_rcvd) < 0) {
log_fn(severity,LD_OR,"Other side, which claims to be router '%s' (%s:%d),"
" has a cert but it's invalid. Closing.",
nickname, conn->address, conn->port);
return -1;
}
check_no_tls_errors();
debug(LD_OR,"The router's cert is valid.");
crypto_pk_get_digest(identity_rcvd, digest_rcvd);
if (crypto_pk_cmp_keys(get_identity_key(), identity_rcvd)<0) {
conn->circ_id_type = CIRC_ID_TYPE_LOWER;
} else {
conn->circ_id_type = CIRC_ID_TYPE_HIGHER;
}
crypto_free_pk_env(identity_rcvd);
router = router_get_by_nickname(nickname, 0);
if (router && /* we know this nickname */
router->is_named && /* make sure it's the right guy */
memcmp(digest_rcvd, router->cache_info.identity_digest,DIGEST_LEN) !=0) {
log_fn(severity, LD_OR,
"Identity key not as expected for router claiming to be "
"'%s' (%s:%d)",
nickname, conn->address, conn->port);
return -1;
}
if (connection_or_nonopen_was_started_here(conn)) {
int as_advertised = 1;
if (memcmp(digest_rcvd, conn->identity_digest, DIGEST_LEN)) {
/* I was aiming for a particular digest. I didn't get it! */
char seen[HEX_DIGEST_LEN+1];
char expected[HEX_DIGEST_LEN+1];
base16_encode(seen, sizeof(seen), digest_rcvd, DIGEST_LEN);
base16_encode(expected, sizeof(expected), conn->identity_digest,
DIGEST_LEN);
log_fn(severity, LD_OR,
"Identity key not as expected for router at %s:%d: wanted %s "
"but got %s",
conn->address, conn->port, expected, seen);
entry_guard_set_status(conn->identity_digest, 0);
control_event_or_conn_status(conn, OR_CONN_EVENT_FAILED);
as_advertised = 0;
}
if (authdir_mode(options)) {
/* We initiated this connection to address:port. Drop all routers
* with the same address:port and a different key or nickname.
*/
dirserv_orconn_tls_done(conn->address, conn->port,
digest_rcvd, nickname, as_advertised);
}
if (!as_advertised)
return -1;
}
return 0;
}
/** The tls handshake is finished.
*
* Make sure we are happy with the person we just handshaked with.
*
* If he initiated the connection, make sure he's not already connected,
* then initialize conn from the information in router.
*
* If I'm not a server, set bandwidth to the default OP bandwidth.
*
* If all is successful, call circuit_n_conn_done() to handle events
* that have been pending on the tls handshake completion. Also set the
* directory to be dirty (only matters if I'm an authdirserver).
*/
static int
connection_tls_finish_handshake(connection_t *conn)
{
char digest_rcvd[DIGEST_LEN];
int started_here = connection_or_nonopen_was_started_here(conn);
debug(LD_OR,"tls handshake done. verifying.");
if (connection_or_check_valid_handshake(conn, digest_rcvd) < 0)
return -1;
if (!started_here) {
#if 0
connection_t *c;
if ((c=connection_or_get_by_identity_digest(digest_rcvd))) {
debug(LD_OR,"Router '%s' is already connected on fd %d. Dropping fd %d.",
c->nickname, c->s, conn->s);
return -1;
}
#endif
connection_or_init_conn_from_address(conn,conn->addr,conn->port,
digest_rcvd);
}
if (!server_mode(get_options())) { /* If I'm an OP... */
conn->receiver_bucket = conn->bandwidth = DEFAULT_BANDWIDTH_OP;
}
directory_set_dirty();
conn->state = OR_CONN_STATE_OPEN;
control_event_or_conn_status(conn, OR_CONN_EVENT_CONNECTED);
if (started_here) {
rep_hist_note_connect_succeeded(conn->identity_digest, time(NULL));
if (entry_guard_set_status(conn->identity_digest, 1) < 0) {
/* pending circs get closed in circuit_about_to_close_connection() */
return -1;
}
}
connection_watch_events(conn, EV_READ);
circuit_n_conn_done(conn, 1); /* send the pending creates, if any. */
return 0;
}
/** Pack cell into wire-format, and write it onto conn's
* outbuf.
*
* If it's an OR conn, and an entire TLS record is
* ready, then try to flush the record now.
*/
void
connection_or_write_cell_to_buf(const cell_t *cell, connection_t *conn)
{
char networkcell[CELL_NETWORK_SIZE];
char *n = networkcell;
tor_assert(cell);
tor_assert(conn);
tor_assert(connection_speaks_cells(conn));
cell_pack(n, cell);
connection_write_to_buf(n, CELL_NETWORK_SIZE, conn);
#define MIN_TLS_FLUSHLEN 15872
/* openssl tls record size is 16383, this is close. The goal here is to
* push data out as soon as we know there's enough for a tls record, so
* during periods of high load we won't read the entire megabyte from
* input before pushing any data out. It also has the feature of not
* growing huge outbufs unless something is slow. */
if (conn->outbuf_flushlen-CELL_NETWORK_SIZE < MIN_TLS_FLUSHLEN &&
conn->outbuf_flushlen >= MIN_TLS_FLUSHLEN) {
int extra = conn->outbuf_flushlen - MIN_TLS_FLUSHLEN;
conn->outbuf_flushlen = MIN_TLS_FLUSHLEN;
if (connection_handle_write(conn) < 0) {
if (!conn->marked_for_close) {
/* this connection is broken. remove it. */
warn(LD_BUG,
"Bug: unhandled error on write for OR conn (fd %d); removing",
conn->s);
tor_fragile_assert();
conn->has_sent_end = 1; /* don't cry wolf about duplicate close */
/* XXX do we need a close-immediate here, so we don't try to flush? */
connection_mark_for_close(conn);
}
return;
}
if (extra) {
conn->outbuf_flushlen += extra;
connection_start_writing(conn);
}
}
}
/** Process cells from conn's inbuf.
*
* Loop: while inbuf contains a cell, pull it off the inbuf, unpack it,
* and hand it to command_process_cell().
*
* Always return 0.
*/
static int
connection_or_process_cells_from_inbuf(connection_t *conn)
{
char buf[CELL_NETWORK_SIZE];
cell_t cell;
loop:
debug(LD_OR,"%d: starting, inbuf_datalen %d (%d pending in tls object).",
conn->s,(int)buf_datalen(conn->inbuf),
tor_tls_get_pending_bytes(conn->tls));
if (buf_datalen(conn->inbuf) < CELL_NETWORK_SIZE) /* whole response
available? */
return 0; /* not yet */
connection_fetch_from_buf(buf, CELL_NETWORK_SIZE, conn);
/* retrieve cell info from buf (create the host-order struct from the
* network-order string) */
cell_unpack(&cell, buf);
command_process_cell(&cell, conn);
goto loop; /* process the remainder of the buffer */
}
/** Write a destroy cell with circ ID circ_id and reason reason
* onto OR connection conn. Don't perform range-checking on reason:
* we may want to propagate reasons from other cells.
*
* Return 0.
*/
int
connection_or_send_destroy(uint16_t circ_id, connection_t *conn, int reason)
{
cell_t cell;
tor_assert(conn);
tor_assert(connection_speaks_cells(conn));
memset(&cell, 0, sizeof(cell_t));
cell.circ_id = circ_id;
cell.command = CELL_DESTROY;
cell.payload[0] = (uint8_t) reason;
debug(LD_OR,"Sending destroy (circID %d).", circ_id);
connection_or_write_cell_to_buf(&cell, conn);
return 0;
}