start allowing clients to give up on trackhostexits targets if

five circuit attempts fail for a given stream. part of the fix
for bug 437. still an XXX020rc remaining.


svn:r13648
This commit is contained in:
Roger Dingledine 2008-02-21 09:00:54 +00:00
parent 18a209ffe6
commit a60f7caa54
4 changed files with 43 additions and 6 deletions

View File

@ -2876,7 +2876,7 @@ assert_connection_ok(connection_t *conn, time_t now)
assert_buf_ok(conn->outbuf);
}
if (conn->chosen_exit_optional) {
if (conn->chosen_exit_optional || conn->chosen_exit_retries) {
tor_assert(conn->type == CONN_TYPE_AP);
tor_assert((TO_EDGE_CONN(conn))->chosen_exit_name);
}

View File

@ -472,13 +472,16 @@ circuit_discard_optional_exit_enclaves(extend_info_t *info)
if (conn->marked_for_close ||
conn->type != CONN_TYPE_AP ||
conn->state != AP_CONN_STATE_CIRCUIT_WAIT ||
!conn->chosen_exit_optional)
(!conn->chosen_exit_optional &&
!conn->chosen_exit_retries))
continue;
edge_conn = TO_EDGE_CONN(conn);
r1 = router_get_by_nickname(edge_conn->chosen_exit_name, 0);
r2 = router_get_by_nickname(info->nickname, 0);
if (r1 && r2 && r1==r2) {
tor_assert(edge_conn->socks_request);
if (!r1 || !r2 || r1 != r2)
continue;
tor_assert(edge_conn->socks_request);
if (conn->chosen_exit_optional) {
log_info(LD_APP, "Giving up on enclave exit '%s' for destination %s.",
safe_str(edge_conn->chosen_exit_name),
escaped_safe_str(edge_conn->socks_request->address));
@ -488,6 +491,16 @@ circuit_discard_optional_exit_enclaves(extend_info_t *info)
* think it'll be using an enclave. */
consider_plaintext_ports(edge_conn, edge_conn->socks_request->port);
}
if (conn->chosen_exit_retries) {
if (--conn->chosen_exit_retries == 0) { /* give up! */
/* XXX020rc unregister maps from foo to
* foo.chosen_exit_name.exit \forall foo. -RD */
tor_free(edge_conn->chosen_exit_name); /* clears it */
/* if this port is dangerous, warn or reject it now that we don't
* think it'll be using an enclave. */
consider_plaintext_ports(edge_conn, edge_conn->socks_request->port);
}
}
});
}
@ -1244,6 +1257,7 @@ connection_ap_handshake_rewrite_and_attach(edge_connection_t *conn,
int automap = 0;
char orig_address[MAX_SOCKS_ADDR_LEN];
time_t map_expires = TIME_MAX;
int remapped_to_exit = 0;
time_t now = time(NULL);
tor_strlower(socks->address); /* normalize it */
@ -1299,11 +1313,16 @@ connection_ap_handshake_rewrite_and_attach(edge_connection_t *conn,
}
}
} else if (!automap) {
int started_without_chosen_exit = strcasecmpend(socks->address, ".exit");
/* For address map controls, remap the address. */
if (addressmap_rewrite(socks->address, sizeof(socks->address),
&map_expires)) {
control_event_stream_status(conn, STREAM_EVENT_REMAP,
REMAP_STREAM_SOURCE_CACHE);
if (started_without_chosen_exit &&
!strcasecmpend(socks->address, ".exit") &&
map_expires < TIME_MAX)
remapped_to_exit = 1;
}
}
@ -1340,6 +1359,10 @@ connection_ap_handshake_rewrite_and_attach(edge_connection_t *conn,
if (s) {
if (s[1] != '\0') {
conn->chosen_exit_name = tor_strdup(s+1);
/* DOCDOC */
#define TRACKHOSTEXITS_RETRIES 5
if (remapped_to_exit) /* 5 tries before it expires the addressmap */
TO_CONN(conn)->chosen_exit_retries = TRACKHOSTEXITS_RETRIES;
*s = 0;
} else {
log_warn(LD_APP,"Malformed exit address '%s.exit'. Refusing.",

View File

@ -811,6 +811,11 @@ typedef struct connection_t {
/** For AP connections only. If 1, and we fail to reach the chosen exit,
* stop requiring it. */
unsigned int chosen_exit_optional:1;
/** For AP connections only. If non-zero, this exit node was picked as
* a result of the TrackHostExit, and the value decrements every time
* we fail to complete a circuit to our chosen exit -- if it reaches
* zero, abandon the associated mapaddress. */
unsigned int chosen_exit_retries:3;
/** Set to 1 when we're inside connection_flushed_some to keep us from
* calling connection_handle_write() recursively. */
unsigned int in_flushed_some:1;
@ -861,7 +866,7 @@ typedef struct connection_t {
* we marked for close? */
char *address; /**< FQDN (or IP) of the guy on the other end.
* strdup into this, because free_connection frees it. */
/** Annother connection that's connected to this one in lieu of a socket. */
/** Another connection that's connected to this one in lieu of a socket. */
struct connection_t *linked_conn;
/* XXXX021 move this into a subtype. */

View File

@ -771,9 +771,18 @@ connection_edge_process_end_not_open(
NULL)) {
control_event_stream_status(conn, STREAM_EVENT_REMAP, 0);
}
if (conn->_base.chosen_exit_optional) {
if (conn->_base.chosen_exit_optional ||
conn->_base.chosen_exit_retries) {
/* stop wanting a specific exit */
conn->_base.chosen_exit_optional = 0;
/* A non-zero chosen_exit_retries can happen if we set a
* TrackHostExits for this address under a port that the exit
* relay allows, but then try the same address with a different
* port that it doesn't allow to exit. We shouldn't unregister
* the mapping, since it is probably still wanted on the
* original port. But now we give away to the exit relay that
* we probably have a TrackHostExits on it. So be it. */
conn->_base.chosen_exit_retries = 0;
tor_free(conn->chosen_exit_name); /* clears it */
}
if (connection_ap_detach_retriable(conn, circ, control_reason) >= 0)