Files
tor/src/or/connection_exit.c
T
Roger Dingledine 117cbeeaaf Implemented link padding and receiver token buckets
Each socket reads at most 'bandwidth' bytes per second sustained, but
can handle bursts of up to 10*bandwidth bytes.

Cells are now sent out at evenly-spaced intervals, with padding sent
out otherwise. Set Linkpadding=0 in the rc file to send cells as soon
as they're available (and to never send padding cells).

Added license/copyrights statements at the top of most files.

router->min and router->max have been merged into a single 'bandwidth'
value. We should make the routerinfo_t reflect this (want to do that,
Mat?)

As the bandwidth increases, and we want to stop sleeping more and more
frequently to send a single cell, cpu usage goes up. At 128kB/s we're
pretty much calling poll with a timeout of 1ms or even 0ms. The current
code takes a timeout of 0-9ms and makes it 10ms. prepare_for_poll()
handles everything that should have happened in the past, so as long as
our buffers don't get too full in that 10ms, we're ok.

Speaking of too full, if you run three servers at 100kB/s with -l debug,
it spends too much time printing debugging messages to be able to keep
up with the cells. The outbuf ultimately fills up and it kills that
connection. If you run with -l err, it works fine up through 500kB/s and
probably beyond. Down the road we'll want to teach it to recognize when
an outbuf is getting full, and back off.


svn:r50
2002-07-16 01:12:15 +00:00

174 lines
6.7 KiB
C

/* Copyright 2001,2002 Roger Dingledine, Matej Pfajfar. */
/* See LICENSE for licensing information */
/* $Id$ */
#include "or.h"
int connection_exit_process_inbuf(connection_t *conn) {
assert(conn && conn->type == CONN_TYPE_EXIT);
if(conn->inbuf_reached_eof) {
/* eof reached, kill it. */
log(LOG_DEBUG,"connection_exit_process_inbuf(): conn reached eof. Closing.");
return -1;
}
log(LOG_DEBUG,"connection_exit_process_inbuf(): state %d.",conn->state);
switch(conn->state) {
case EXIT_CONN_STATE_CONNECTING:
log(LOG_DEBUG,"connection_exit_process_inbuf(): text from server while in 'connecting' state. Leaving it on buffer.");
return 0;
case EXIT_CONN_STATE_OPEN:
return connection_package_raw_inbuf(conn);
}
return 0;
}
int connection_exit_finished_flushing(connection_t *conn) {
int e, len=sizeof(e);
assert(conn && conn->type == CONN_TYPE_EXIT);
switch(conn->state) {
case EXIT_CONN_STATE_CONNECTING:
if (getsockopt(conn->s, SOL_SOCKET, SO_ERROR, &e, &len) < 0) { /* not yet */
if(errno != EINPROGRESS){
/* yuck. kill it. */
log(LOG_DEBUG,"connection_exit_finished_flushing(): in-progress connect failed. Removing.");
return -1;
} else {
log(LOG_DEBUG,"connection_exit_finished_flushing(): in-progress connect still waiting.");
return 0; /* no change, see if next time is better */
}
}
/* the connect has finished. */
log(LOG_DEBUG,"connection_exit_finished_flushing() : Connection to %s:%u established.",
conn->address,ntohs(conn->port));
conn->state = EXIT_CONN_STATE_OPEN;
connection_flush_buf(conn); /* in case there are any queued data cells */
connection_watch_events(conn, POLLIN);
return 0;
case EXIT_CONN_STATE_OPEN:
/* FIXME down the road, we'll clear out circuits that are pending to close */
connection_watch_events(conn, POLLIN);
return 0;
default:
log(LOG_DEBUG,"Bug: connection_exit_finished_flushing() called in unexpected state.");
return 0;
}
return 0;
}
int connection_exit_process_data_cell(cell_t *cell, connection_t *conn) {
struct hostent *rent;
struct sockaddr_in dest_addr;
int s; /* for the new socket, if we're on connecting_wait */
/* an outgoing data cell has arrived */
assert(conn && conn->type == CONN_TYPE_EXIT);
switch(conn->state) {
case EXIT_CONN_STATE_CONNECTING_WAIT:
log(LOG_DEBUG,"connection_exit_process_data_cell(): state is connecting_wait. cell length %d.", cell->length);
if(!conn->ss_received) { /* this cell contains the ss */
if(cell->length != sizeof(ss_t)) {
log(LOG_DEBUG,"connection_exit_process_data_cell(): Supposed to contain SS but wrong size. Closing.");
return -1;
}
memcpy(&conn->ss, cell->payload, cell->length);
if(conn->ss.addr_fmt != SS_ADDR_FMT_ASCII_HOST_PORT) { /* unrecognized address format */
log(LOG_DEBUG,"connection_exit_process_data_cell(): SS has unrecognized address format. Closing.");
return -1;
}
conn->ss_received = 1;
log(LOG_DEBUG,"connection_exit_process_data_cell(): SS received.");
} else if (!conn->addr) { /* this cell contains the dest addr */
if(!memchr(cell->payload,0,cell->length)) {
log(LOG_DEBUG,"connection_exit_process_data_cell(): dest_addr cell has no \\0. Closing.");
return -1;
}
conn->address = strdup(cell->payload);
rent = gethostbyname(cell->payload);
if (!rent) {
log(LOG_ERR,"connection_exit_process_data_cell(): Could not resolve dest addr %s.",cell->payload);
return -1;
}
memcpy(&conn->addr, rent->h_addr,rent->h_length);
log(LOG_DEBUG,"connection_exit_process_data_cell(): addr %s resolves to %d.",cell->payload,conn->addr);
} else if (!conn->port) { /* this cell contains the dest port */
if(!memchr(cell->payload,'\0',cell->length)) {
log(LOG_DEBUG,"connection_exit_process_data_cell(): dest_port cell has no \\0. Closing.");
return -1;
}
conn->port = atoi(cell->payload);
if(!conn->port) { /* bad port */
log(LOG_DEBUG,"connection_exit_process_data_cell(): dest_port cell isn't a valid number. Closing.");
return -1;
}
/* all the necessary info is here. Start the connect() */
s=socket(PF_INET,SOCK_STREAM,IPPROTO_TCP);
if (s < 0)
{
log(LOG_ERR,"connection_exit_process_data_cell(): Error creating network socket.");
return -1;
}
fcntl(s, F_SETFL, O_NONBLOCK); /* set s to non-blocking */
memset((void *)&dest_addr,0,sizeof(dest_addr));
dest_addr.sin_family = AF_INET;
dest_addr.sin_port = conn->port;
memcpy((void *)&dest_addr.sin_addr, &conn->addr, sizeof(uint32_t));
log(LOG_DEBUG,"connection_exit_process_data_cell(): Connecting to %s:%u.",conn->address,ntohs(conn->port));
if(connect(s,(struct sockaddr *)&dest_addr,sizeof(dest_addr)) < 0){
if(errno != EINPROGRESS){
/* yuck. kill it. */
log(LOG_DEBUG,"connection_exit_process_data_cell(): Connect failed.");
return -1;
} else {
/* it's in progress. set state appropriately and return. */
conn->s = s;
connection_set_poll_socket(conn);
conn->state = EXIT_CONN_STATE_CONNECTING;
/* i think only pollout is needed, but i'm curious if pollin ever gets caught -RD */
log(LOG_DEBUG,"connection_exit_process_data_cell(): connect in progress, socket %d.",s);
connection_watch_events(conn, POLLOUT | POLLIN);
return 0;
}
}
/* it succeeded. we're connected. */
log(LOG_DEBUG,"connection_exit_process_data_cell(): Connection to %s:%u established.",conn->address,ntohs(conn->port));
conn->s = s;
connection_set_poll_socket(conn);
conn->state = EXIT_CONN_STATE_OPEN;
connection_watch_events(conn, POLLIN);
return 0;
} else {
log(LOG_DEBUG,"connection_exit_process_data_cell(): in connecting_wait, but I've already received everything. Closing.");
return -1;
}
return 0;
case EXIT_CONN_STATE_CONNECTING:
log(LOG_DEBUG,"connection_exit_process_data_cell(): Data receiving while connecting. Queueing.");
/* this sets us to POLLOUT | POLLIN, which is ok because we need to keep listening for
* writable for connect() to finish */
return connection_write_to_buf(cell->payload, cell->length, conn);
case EXIT_CONN_STATE_OPEN:
return connection_write_to_buf(cell->payload, cell->length, conn);
}
return 0;
}