Improve data flow, better debugging, fixed ping CMC and frag timeout

This commit is contained in:
frekky 2015-11-10 20:54:01 +08:00
parent f96bd3735d
commit 4a565fd664

View File

@ -350,13 +350,17 @@ immediate_mode_defaults()
/* Client-side query tracking for lazy mode */
/* Handy macro for printing stats with messages */
#ifdef DEBUG_BUILD
#define QTRACK_DEBUG(l, ...) \
if (debug >= l) {\
fprintf(stderr, "[QTRACK (%lu/%lu), ? %lu, TO %lu, S %lu/%lu] ", num_pending, PENDING_QUERIES_LENGTH, \
num_untracked, num_timeouts, window_sending(outbuf), outbuf->numitems); \
TIMEPRINT("[QTRACK (%lu/%lu), ? %lu, TO %lu, S %lu/%lu] ", num_pending, PENDING_QUERIES_LENGTH, \
num_untracked, num_timeouts, window_sending(outbuf, NULL), outbuf->numitems); \
fprintf(stderr, __VA_ARGS__);\
fprintf(stderr, "\n");\
}
#else
#define QTRACK_DEBUG(...)
#endif
static int
update_server_timeout(int dns_fd, int handshake)
@ -558,18 +562,22 @@ send_query(int fd, uint8_t *hostname)
And there are relays where, in lazy mode, our new query apparently
_replaces_ our previous query, and we get no answers at all in
lazy mode while legacy immediate-ping-pong works just fine.
In this case, the up/down windowsizes may need to be set to 1 for there
to only ever be one query pending.
Here we detect and fix these situations.
(Can't very well do this anywhere else; this is the only place
we'll reliably get to in such situations.)
Note: only start fixing up connection AFTER we have connected */
Note: only start fixing up connection AFTER we have connected
and if user hasn't specified server timeout/window timeout etc. */
num_sent++;
if (send_query_sendcnt >= 0 && send_query_sendcnt < 100 && lazymode && connected) {
if (send_query_sendcnt >= 0 && send_query_sendcnt < 100 &&
lazymode && connected && autodetect_server_timeout) {
send_query_sendcnt++;
if ((send_query_sendcnt > windowsize_down && send_query_recvcnt <= 0) ||
(send_query_sendcnt > 2 * windowsize_down && 4 * send_query_recvcnt < send_query_sendcnt)) {
if (max_timeout_ms > 500 && autodetect_server_timeout) {
if (max_timeout_ms > 500) {
max_timeout_ms -= 200;
double secs = (double) max_timeout_ms / 1000.0;
fprintf(stderr, "Receiving too few answers. Setting target timeout to %.1fs (-I%.1f)\n", secs, secs);
@ -578,7 +586,7 @@ send_query(int fd, uint8_t *hostname)
send_query_sendcnt = 0;
send_query_recvcnt = 0;
} else if (lazymode && autodetect_server_timeout) {
} else if (lazymode) {
fprintf(stderr, "Receiving too few answers. Will try to switch lazy mode off, but that may not"
" always work any more. Start with -L0 next time on this network.\n");
lazymode = 0;
@ -635,7 +643,7 @@ send_ping(int fd, int ping_response, int ack, int set_timeout)
{
num_pings++;
if (conn == CONN_DNS_NULL) {
uint8_t data[11];
uint8_t data[13];
int id;
/* Build ping header (see doc/proto_xxxxxxxx.txt) */
@ -656,7 +664,7 @@ send_ping(int fd, int ping_response, int ack, int set_timeout)
data[10] = ((set_timeout & 1) << 4) | ((set_timeout & 1) << 3) | ((ack < 0 ? 0 : 1) << 2) | (ping_response & 1);
data[11] = (rand_seed >> 8) & 0xff;
data[12] = (rand_seed >> 0) & 0xff;
rand_seed += 263;
rand_seed += 1;
DEBUG(3, " SEND PING: respond %d, ack %d, %s(server %ld ms, downfrag %ld ms), flags %02X",
ping_response, ack, set_timeout ? "SET " : "", server_timeout_ms,
@ -682,7 +690,7 @@ send_next_frag(int fd)
static int datacmc = 0;
static char *datacmcchars = "abcdefghijklmnopqrstuvwxyz0123456789";
fragment *f;
size_t buflen, len;
size_t buflen;
/* Get next fragment to send */
f = window_get_next_sending_fragment(outbuf, &next_downstream_ack);
@ -712,9 +720,7 @@ send_next_frag(int fd)
buflen = sizeof(buf) - 1;
/* Encode 3 bytes data into 2 bytes after buf */
len = b32->encode(buf + 2, &buflen, hdr, 3);
if (len != 5)
warnx("mismatch in encoded upstream header length! expected 5, got %lu", len);
b32->encode(buf + 2, &buflen, hdr, 3);
/* Encode data into buf after header (6 = user + CMC + 4 bytes header) */
build_hostname(buf, sizeof(buf), f->data, f->len, topdomain,
@ -724,6 +730,9 @@ send_next_frag(int fd)
if (datacmc >= 36)
datacmc = 0;
DEBUG(3, " SEND DATA: seq %d, ack %d, len %lu, s%d e%d c%d flags %1X",
f->seqID, f->ack_other, f->len, f->start, f->end, f->compressed, hdr[2] >> 4);
id = send_query(fd, buf);
/* Log query ID as being sent now */
query_sent_now(id);
@ -1315,10 +1324,10 @@ tunnel_dns(int tun_fd, int dns_fd)
int
client_tunnel(int tun_fd, int dns_fd)
{
struct timeval tv;
struct timeval tv, nextresend, tmp, now, now2;
fd_set fds;
int rv;
int i;
int i, use_min_send;
int sending, total;
time_t last_stats;
size_t sent_since_report, recv_since_report;
@ -1345,16 +1354,21 @@ client_tunnel(int tun_fd, int dns_fd)
sent_since_report = 0;
recv_since_report = 0;
use_min_send = 0;
if (debug >= 5)
window_debug = debug - 3;
while (running) {
tv = ms_to_timeval(max_timeout_ms);
if (!use_min_send)
tv = ms_to_timeval(max_timeout_ms);
/* TODO: detect DNS servers which drop frequent requests
* TODO: adjust number of pending queries based on current data rate */
if (conn == CONN_DNS_NULL) {
sending = window_sending(outbuf);
if (conn == CONN_DNS_NULL && !use_min_send) {
/* Send a single query per loop */
sending = window_sending(outbuf, &nextresend);
total = sending;
check_pending_queries();
if (num_pending < windowsize_down && lazymode)
@ -1362,9 +1376,9 @@ client_tunnel(int tun_fd, int dns_fd)
else if (num_pending < 1 && !lazymode)
total = MAX(total, 1);
/* Upstream traffic - this is where all ping/data queries are sent */
if (sending > 0 || total > 0 || next_downstream_ack >= 0) {
/* Upstream traffic - this is where all ping/data queries are sent */
if (sending > 0) {
/* More to send - next fragment */
send_next_frag(dns_fd);
@ -1380,14 +1394,25 @@ client_tunnel(int tun_fd, int dns_fd)
lazymode ? windowsize_down : 1, total);
if (sending > 0 || (total > 0 && lazymode)) {
/* If sending any data fragments, or server has too few
* pending queries, send another one after min. interval */
/* TODO: enforce min send interval even if we get new data */
tv = ms_to_timeval(min_send_interval_ms);
if (min_send_interval_ms)
use_min_send = 1;
tv.tv_usec += 1;
} else if (total > 0 && !lazymode) {
/* use immediate mode send interval if nothing pending */
/* In immediate mode, use normal interval when needing
* to send non-data queries to probe server. */
tv = ms_to_timeval(send_interval_ms);
}
if (sending == 0 && !use_min_send) {
/* check next resend time when not sending any data */
if (timercmp(&nextresend, &tv, <))
tv = nextresend;
}
send_ping_soon = 0;
}
}
@ -1421,7 +1446,7 @@ client_tunnel(int tun_fd, int dns_fd)
}
}
if (send_ping_soon) {
if (send_ping_soon && !use_min_send) {
tv.tv_sec = 0;
tv.tv_usec = send_ping_soon * 1000;
send_ping_soon = 0;
@ -1435,10 +1460,24 @@ client_tunnel(int tun_fd, int dns_fd)
}
FD_SET(dns_fd, &fds);
DEBUG(4, "Waiting %ld ms before sending more...", timeval_to_ms(&tv));
DEBUG(4, "Waiting %ld ms before sending more... (min_send %d)", timeval_to_ms(&tv), use_min_send);
if (use_min_send) {
gettimeofday(&now, NULL);
}
i = select(MAX(tun_fd, dns_fd) + 1, &fds, NULL, NULL, &tv);
if (use_min_send && i > 0) {
/* enforce min_send_interval if we get interrupted by new tun data */
gettimeofday(&now2, NULL);
timersub(&now2, &now, &tmp);
timersub(&tv, &tmp, &now);
tv = now;
} else {
use_min_send = 0;
}
if (difftime(time(NULL), lastdownstreamtime) > 60) {
fprintf(stderr, "No downstream data received in 60 seconds, shutting down.\n");
running = 0;
@ -1451,9 +1490,8 @@ client_tunnel(int tun_fd, int dns_fd)
err(1, "select < 0");
if (i == 0) {
/* TODO check number of timeouts and do something about it */
/* timed out - no new packets recv'd */
} else {
if (FD_ISSET(tun_fd, &fds)) {
if (tunnel_tun(tun_fd, dns_fd) <= 0)
continue;
@ -1462,6 +1500,7 @@ client_tunnel(int tun_fd, int dns_fd)
we need to _not_ do tunnel_dns() then.
If chunk sent, sets send_ping_soon=0. */
}
if (FD_ISSET(dns_fd, &fds)) {
tunnel_dns(tun_fd, dns_fd);
}
@ -2701,6 +2740,7 @@ client_handshake(int dns_fd, int raw_mode, int autodetect_frag_size, int fragsiz
/* init windowing protocol */
outbuf = window_buffer_init(64, windowsize_up, maxfragsize_up, WINDOW_SENDING);
outbuf->timeout = ms_to_timeval(downstream_timeout_ms);
/* Incoming buffer max fragsize doesn't matter */
inbuf = window_buffer_init(64, windowsize_down, MAX_FRAGSIZE, WINDOW_RECVING);