[or-cvs] change when circuits are built and expired
Roger Dingledine
arma at seul.org
Sun Nov 16 21:49:55 UTC 2003
Update of /home/or/cvsroot/src/or
In directory moria.mit.edu:/home2/arma/work/onion/cvs/src/or
Modified Files:
circuit.c connection_edge.c main.c or.h
Log Message:
change when circuits are built and expired
not quite happy with it yet
Index: circuit.c
===================================================================
RCS file: /home/or/cvsroot/src/or/circuit.c,v
retrieving revision 1.94
retrieving revision 1.95
diff -u -d -r1.94 -r1.95
--- circuit.c 16 Nov 2003 17:31:19 -0000 1.94
+++ circuit.c 16 Nov 2003 21:49:52 -0000 1.95
@@ -205,18 +205,45 @@
return NULL;
}
-circuit_t *circuit_get_newest_open(void) {
- circuit_t *circ, *bestcirc=NULL;
+/* Find the newest circ that conn can use, preferably one which is
+ * dirty and not too old.
+ * If !conn, return newest open.
+ */
+circuit_t *circuit_get_newest_open(connection_t *conn) {
+ circuit_t *circ, *newest=NULL, *leastdirty=NULL;
for(circ=global_circuitlist;circ;circ = circ->next) {
- if(circ->cpath && circ->state == CIRCUIT_STATE_OPEN && circ->n_conn && (!bestcirc ||
- bestcirc->timestamp_created < circ->timestamp_created)) {
- log_fn(LOG_DEBUG,"Choosing circuit %s:%d:%d.", circ->n_conn->address, circ->n_port, circ->n_circ_id);
- assert(circ->n_circ_id);
- bestcirc = circ;
+ if(conn && connection_ap_can_use_exit(conn,
+ router_get_by_addr_port(circ->cpath->prev->addr, circ->cpath->prev->port)) < 0) {
+ log_fn(LOG_DEBUG,"Skipping %s:%d:%d because we couldn't exit there.",
+ circ->n_conn->address, circ->n_port, circ->n_circ_id);
+ continue;
+ }
+ if(circ->cpath && circ->state == CIRCUIT_STATE_OPEN && circ->n_conn) {
+ if(!newest || newest->timestamp_created < circ->timestamp_created) {
+ assert(circ->n_circ_id);
+ newest = circ;
+ }
+ if(conn && circ->timestamp_dirty &&
+ (!leastdirty || leastdirty->timestamp_dirty < circ->timestamp_dirty)) {
+ assert(circ->n_circ_id);
+ leastdirty = circ;
+ }
}
}
- return bestcirc;
+
+ if(leastdirty &&
+ leastdirty->timestamp_dirty+options.NewCircuitPeriod > time(NULL)) {
+ log_fn(LOG_DEBUG,"Choosing in-use circuit %s:%d:%d.",
+ leastdirty->n_conn->address, leastdirty->n_port, leastdirty->n_circ_id);
+ return leastdirty;
+ }
+ if(newest) {
+ log_fn(LOG_DEBUG,"Choosing circuit %s:%d:%d.",
+ newest->n_conn->address, newest->n_port, newest->n_circ_id);
+ return newest;
+ }
+ return NULL;
}
int circuit_deliver_relay_cell(cell_t *cell, circuit_t *circ,
@@ -491,13 +518,8 @@
void circuit_close(circuit_t *circ) {
connection_t *conn;
- circuit_t *youngest=NULL;
assert(circ);
- if(options.SocksPort) {
- youngest = circuit_get_newest_open();
- log_fn(LOG_DEBUG,"youngest %d, circ %d.",(int)youngest, (int)circ);
- }
circuit_remove(circ);
if(circ->n_conn)
connection_send_destroy(circ->n_circ_id, circ->n_conn);
@@ -509,11 +531,6 @@
for(conn=circ->p_streams; conn; conn=conn->next_stream) {
connection_send_destroy(circ->p_circ_id, conn);
}
- if(options.SocksPort && youngest == circ) { /* check this after we've sent the destroys, to reduce races */
- /* our current circuit just died. Launch another one pronto. */
- log_fn(LOG_INFO,"Youngest circuit dying. Launching a replacement.");
- circuit_launch_new(1);
- }
circuit_free(circ);
}
@@ -606,15 +623,15 @@
void circuit_expire_unused_circuits(void) {
circuit_t *circ, *tmpcirc;
- circuit_t *youngest;
-
- youngest = circuit_get_newest_open();
+ time_t now = time(NULL);
circ = global_circuitlist;
while(circ) {
tmpcirc = circ;
circ = circ->next;
- if(tmpcirc != youngest && !tmpcirc->p_conn && !tmpcirc->p_streams) {
+ if(tmpcirc->timestamp_dirty &&
+ tmpcirc->timestamp_dirty + options.NewCircuitPeriod < now &&
+ !tmpcirc->p_conn && !tmpcirc->p_streams) {
log_fn(LOG_DEBUG,"Closing n_circ_id %d",tmpcirc->n_circ_id);
circuit_close(tmpcirc);
}
@@ -624,34 +641,33 @@
/* failure_status code: negative means reset failures to 0. Other values mean
* add that value to the current number of failures, then if we don't have too
* many failures on record, try to make a new circuit.
+ *
+ * Return -1 if you aren't going to try to make a circuit, 0 if you did try.
*/
-void circuit_launch_new(int failure_status) {
+int circuit_launch_new(int failure_status) {
static int failures=0;
if(!options.SocksPort) /* we're not an application proxy. no need for circuits. */
- return;
+ return -1;
if(failure_status == -1) { /* I was called because a circuit succeeded */
failures = 0;
- return;
+ return -1;
}
failures += failure_status;
-retry_circuit:
-
if(failures > 5) {
- log_fn(LOG_INFO,"Giving up for now, %d failures.", failures);
- return;
+ return -1;
}
if(circuit_establish_circuit() < 0) {
failures++;
- goto retry_circuit;
+ return 0;
}
failures = 0;
- return;
+ return 0;
}
int circuit_establish_circuit(void) {
Index: connection_edge.c
===================================================================
RCS file: /home/or/cvsroot/src/or/connection_edge.c,v
retrieving revision 1.56
retrieving revision 1.57
diff -u -d -r1.56 -r1.57
--- connection_edge.c 16 Nov 2003 17:00:02 -0000 1.56
+++ connection_edge.c 16 Nov 2003 21:49:52 -0000 1.57
@@ -18,7 +18,6 @@
static uint32_t client_dns_lookup_entry(const char *address);
static void client_dns_set_entry(const char *address, uint32_t val);
-static void client_dns_clean(void);
int connection_edge_process_inbuf(connection_t *conn) {
@@ -255,7 +254,8 @@
addr = ntohl(*cell->payload+RELAY_HEADER_SIZE+1);
client_dns_set_entry(conn->socks_request->address, addr);
conn->state = AP_CONN_STATE_CIRCUIT_WAIT;
- /* XXX Build another circuit as required */
+ if(connection_ap_handshake_attach_circuit(conn) < 0)
+ circuit_launch_new(1); /* Build another circuit to handle this stream */
return 0;
}
log_fn(LOG_INFO,"end cell (%s) for stream %d. Removing stream.",
@@ -489,10 +489,12 @@
if (carray[i]->type != CONN_TYPE_AP ||
carray[i]->type != AP_CONN_STATE_CIRCUIT_WAIT)
continue;
- if (connection_ap_handshake_attach_circuit(carray[i])) {
- need_new_circuit = 1; /* XXX act on this. */
+ if (connection_ap_handshake_attach_circuit(carray[i])<0) {
+ need_new_circuit = 1;
}
}
+ if(need_new_circuit)
+ circuit_launch_new(1);
}
static void connection_edge_consider_sending_sendme(connection_t *conn) {
@@ -547,51 +549,37 @@
} /* else socks handshake is done, continue processing */
conn->state = AP_CONN_STATE_CIRCUIT_WAIT;
- if (connection_ap_handshake_attach_circuit(conn)) {
- /* XXX we need a circuit */
- }
+ if (connection_ap_handshake_attach_circuit(conn)<0) {
+ circuit_launch_new(1);
+ }
return 0;
}
/* Try to find a live circuit. If we don't find one, tell 'conn' to
* stop reading and return 0. Otherwise, associate the CONN_TYPE_AP
- * connection 'conn' with the newest live circuit, start sending a
+ * connection '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;
-
+
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_open();
+ circ = circuit_get_newest_open(conn);
if(!circ) {
- log_fn(LOG_INFO,"No circuit ready for edge connection; delaying.");
- connection_stop_reading(conn);
- /* XXX both this and the start_reading below can go away if we
- * remove our notion that we shouldn't read from a socks
- * client until we're connected. the socks spec promises that it
- * won't write. is that good enough?
- */
- return -1;
- }
- if (connection_ap_can_use_exit(conn,
- router_get_by_addr_port(circ->cpath->prev->addr,
- circ->cpath->prev->port)) < 0) {
- /* The exit on this circuit will _definitely_ reject this connection. */
- log_fn(LOG_INFO,"Most recent circuit will reject AP connection; delaying.");
- /* XXX Build another circuit. */
- connection_stop_reading(conn);
+ log_fn(LOG_INFO,"No safe circuit ready for edge connection; delaying.");
+ connection_stop_reading(conn); /* don't read until the connected cell arrives */
return -1;
}
connection_start_reading(conn);
- circ->dirty = 1;
+ 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);
@@ -893,7 +881,7 @@
}
}
-static void client_dns_clean(void)
+void client_dns_clean(void)
{
struct client_dns_entry **expired_entries;
int n_expired_entries = 0;
Index: main.c
===================================================================
RCS file: /home/or/cvsroot/src/or/main.c,v
retrieving revision 1.145
retrieving revision 1.146
diff -u -d -r1.145 -r1.146
--- main.c 16 Nov 2003 17:00:02 -0000 1.145
+++ main.c 16 Nov 2003 21:49:52 -0000 1.146
@@ -335,20 +335,31 @@
time_to_fetch_directory = now + options.DirFetchPostPeriod;
}
- /* 2. Every NewCircuitPeriod seconds, we expire old circuits and make a
- * new one as needed.
+ /* 2. Every second, we try a new circuit if there are no valid
+ * circuits. Every NewCircuitPeriod seconds, we expire circuits
+ * that became dirty more than NewCircuitPeriod seconds ago,
+ * and we make a new circ if there are no clean circuits.
*/
- if(options.SocksPort && time_to_new_circuit < now) {
- circuit_expire_unused_circuits();
- circuit_launch_new(-1); /* tell it to forget about previous failures */
- circ = circuit_get_newest_open();
- if(!circ || circ->dirty) {
- log_fn(LOG_INFO,"Youngest circuit %s; launching replacement.", circ ? "dirty" : "missing");
- circuit_launch_new(0); /* make an onion and lay the circuit */
+ if(options.SocksPort) {
+ circ = circuit_get_newest_open(NULL);
+ if(time_to_new_circuit < now) {
+ client_dns_clean();
+ circuit_expire_unused_circuits();
+ circuit_launch_new(-1); /* tell it to forget about previous failures */
+ if(circ && circ->timestamp_dirty) {
+ log_fn(LOG_INFO,"Youngest circuit dirty; launching replacement.");
+ circuit_launch_new(0); /* make a new circuit */
+ }
+ time_to_new_circuit = now + options.NewCircuitPeriod;
}
- time_to_new_circuit = now + options.NewCircuitPeriod;
+ if(!circ) {
+ circuit_launch_new(1);
+ }
+ /* XXX also check if we have any circuit_pending streams and we're not
+ * currently building a circuit for them.
+ */
}
-
+
/* 3. Every second, we check how much bandwidth we've consumed and
* increment global_read_bucket.
*/
@@ -358,7 +369,6 @@
log_fn(LOG_DEBUG,"global_read_bucket now %d.", global_read_bucket);
}
stats_prev_global_read_bucket = global_read_bucket;
-
/* 4. We do houskeeping for each connection... */
for(i=0;i<nfds;i++) {
@@ -368,6 +378,8 @@
/* 5. and blow away any connections that need to die. can't do this later
* because we might open up a circuit and not realize we're about to cull
* the connection it's running over.
+ * XXX we can remove this step once we audit circuit-building to make sure
+ * it doesn't pick a marked-for-close conn. -RD
*/
for(i=0;i<nfds;i++)
conn_close_if_marked(i);
Index: or.h
===================================================================
RCS file: /home/or/cvsroot/src/or/or.h,v
retrieving revision 1.187
retrieving revision 1.188
diff -u -d -r1.187 -r1.188
--- or.h 16 Nov 2003 17:00:02 -0000 1.187
+++ or.h 16 Nov 2003 21:49:52 -0000 1.188
@@ -419,7 +419,7 @@
char onionskin[DH_ONIONSKIN_LEN]; /* for storage while onionskin pending */
long timestamp_created;
- uint8_t dirty; /* whether this circuit has been used yet */
+ long timestamp_dirty; /* when the circuit was first used, or 0 if clean */
uint8_t state;
@@ -515,7 +515,7 @@
circuit_t *circuit_enumerate_by_naddr_nport(circuit_t *start, uint32_t naddr, uint16_t nport);
circuit_t *circuit_get_by_circ_id_conn(circ_id_t circ_id, connection_t *conn);
circuit_t *circuit_get_by_conn(connection_t *conn);
-circuit_t *circuit_get_newest_open(void);
+circuit_t *circuit_get_newest_open(connection_t *conn);
int circuit_deliver_relay_cell(cell_t *cell, circuit_t *circ,
int cell_direction, crypt_path_t *layer_hint);
@@ -533,7 +533,7 @@
void circuit_dump_by_conn(connection_t *conn, int severity);
void circuit_expire_unused_circuits(void);
-void circuit_launch_new(int failure_status);
+int circuit_launch_new(int failure_status);
int circuit_establish_circuit(void);
void circuit_n_conn_open(connection_t *or_conn);
int circuit_send_next_onion_skin(circuit_t *circ);
@@ -631,6 +631,7 @@
extern uint64_t stats_n_data_bytes_received;
void client_dns_init(void);
+void client_dns_clean(void);
/********************************* connection_or.c ***************************/
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