mirror of
https://github.com/yarrick/iodine.git
synced 2024-11-25 02:55:15 +00:00
Re-implemented working DNS tunnelling (with windows!)
This commit is contained in:
frekky
parent
9f6033c4b8
commit
0449c465e7
376
src/client.c
376
src/client.c
@ -61,6 +61,8 @@
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static void handshake_lazyoff(int dns_fd);
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int debug;
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static int running;
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static const char *password;
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@ -238,7 +240,7 @@ client_set_hostname_maxlen(size_t i)
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{
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if (i <= 0xFF && i != hostname_maxlen) {
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hostname_maxlen = i;
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outbuf->maxfraglen = get_raw_length(hostname_maxlen, dataenc, topdomain);
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outbuf->maxfraglen = get_raw_length_from_dns(hostname_maxlen - UPSTREAM_HDR, dataenc, topdomain);
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}
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}
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@ -257,12 +259,15 @@ client_rotate_nameserver()
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}
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static void
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send_query(int fd, char *hostname)
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send_query(int fd, uint8_t *hostname)
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{
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char packet[4096];
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uint8_t packet[4096];
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struct query q;
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size_t len;
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if (debug >= 2)
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fprintf(stderr, "TX: pkt len %lu: hostname '%s'\n", strlen((char *)hostname), hostname);
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chunkid += 7727;
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if (chunkid == 0)
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/* 0 is used as "no-query" in iodined.c */
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@ -271,15 +276,14 @@ send_query(int fd, char *hostname)
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q.id = chunkid;
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q.type = do_qtype;
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len = dns_encode(packet, sizeof(packet), &q, QR_QUERY, hostname, strlen(hostname));
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len = dns_encode((char *)packet, sizeof(packet), &q, QR_QUERY, (char *)hostname, strlen((char *)hostname));
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if (len < 1) {
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warnx("dns_encode doesn't fit");
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return;
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}
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#if 0
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fprintf(stderr, " Sendquery: id %5d name[0] '%c'\n", q.id, hostname[0]);
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#endif
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if (debug >= 3)
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fprintf(stderr, " Sendquery: id %5d name[0] '%c'\n", q.id, hostname[0]);
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sendto(fd, packet, len, 0, (struct sockaddr*) &nameserv_addrs[current_nameserver],
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sizeof(struct sockaddr_storage));
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@ -347,14 +351,15 @@ send_raw_data(int dns_fd) // TODO: fix send_raw
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static void
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send_packet(int fd, char cmd, const char *data, const size_t datalen)
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send_packet(int fd, char cmd, const uint8_t *data, const size_t datalen)
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/* Base32 encodes data and sends as single DNS query */
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{
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char buf[4096];
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uint8_t buf[4096];
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buf[0] = cmd;
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build_hostname(buf, sizeof(buf), data, datalen, topdomain, b32, hostname_maxlen, 1);
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send_query(fd, buf);
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}
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@ -364,21 +369,28 @@ is_sending()
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return (outbuf->numitems > 0);
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}
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static inline int
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is_recving()
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{
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return inbuf->numitems > 0;
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}
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static void
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send_ping(int fd, int ping_response) // TODO: setup window sync stuff in ping
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send_ping(int fd, int ping_response, int ack) // TODO: setup window sync stuff in ping
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{
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if (conn == CONN_DNS_NULL) {
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char data[4];
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uint8_t data[9];
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data[0] = userid;
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data[1] = inbuf->start_seq_id & 0xff;
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data[2] = outbuf->start_seq_id & 0xff;
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data[3] = outbuf->windowsize & 0xff;
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data[4] = inbuf->windowsize & 0xff;
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data[5] = ping_response & 1;
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data[6] = (rand_seed >> 8) & 0xff;
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data[7] = (rand_seed >> 0) & 0xff;
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rand_seed += 7;
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data[1] = ack & 0xFF;
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data[2] = outbuf->windowsize & 0xff;
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data[3] = inbuf->windowsize & 0xff;
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data[4] = inbuf->start_seq_id & 0xff; /* Downstream window start */
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data[5] = outbuf->start_seq_id & 0xff; /* Upstream window start */
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data[6] = ((ack < 0 ? 0 : 1) << 2) | (ping_response & 1);
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data[7] = (rand_seed >> 8) & 0xff;
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data[8] = (rand_seed >> 0) & 0xff;
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rand_seed += 263;
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send_packet(fd, 'p', data, sizeof(data));
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} else {
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@ -390,49 +402,54 @@ static void
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send_next_frag(int fd)
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/* Sends next available fragment of data from the outgoing window buffer */
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{
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static uint8_t buf[MAX_FRAGSIZE];
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static uint8_t buf[MAX_FRAGSIZE], hdr[5];
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int code;
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static int datacmc = 0;
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static char *datacmcchars = "abcdefghijklmnopqrstuvwxyz0123456789";
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fragment *f;
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size_t buflen, len;
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/* Get next fragment to send */
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f = window_get_next_sending_fragment(outbuf, next_downstream_ack);
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if (f == NULL) {
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f = window_get_next_sending_fragment(outbuf, &next_downstream_ack);
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if (!f) {
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if (is_sending()) {
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/* There is stuff to send but we're out of sync, so send a ping
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* to get things back in order and keep the packets flowing */
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send_ping(fd, 1);
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send_ping(fd, 1, next_downstream_ack);
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next_downstream_ack = -1;
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window_tick(outbuf);
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}
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return; /* nothing to send - why was this called? */
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}
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/* Note: must be same, or smaller than send_fragsize_probe() */
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build_hostname((char *)buf, sizeof(buf), (char *)f->data, f->len, topdomain,
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dataenc, hostname_maxlen, 6);
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/* Build upstream data header (see doc/proto_xxxxxxxx.txt) */
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buf[0] = userid_char; /* First byte is hex userid */
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buf[1] = datacmcchars[datacmc]; /* Second byte is data-CMC */
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code = (f->seqID & 0xF8) >> 3;
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buf[2] = b32_5to8(code); /* Second byte is 5 bits seqno */
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/* Next 3 bytes is seq ID, downstream ACK and flags */
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code = ((f->ack_other < 0 ? 0 : 1) << 3) | (f->is_nack << 2)
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code = ((f->seqID & 7) << 2) | ((f->ack_other & 0xC0) >> 6);
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buf[3] = b32_5to8(code); /* Third byte is 3 bits seqno, 2 bits downstream ACK */
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hdr[0] = f->seqID & 0xFF;
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hdr[1] = f->ack_other & 0xFF;
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hdr[2] = code << 4; /* Flags are in upper 4 bits - lower 4 unused */
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code = ((f->ack_other & 0x3E) >> 1);
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buf[4] = b32_5to8(code); /* Fourth byte is 5 bits downstream ACK */
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buflen = sizeof(buf) - 1;
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/* Encode 3 bytes data into 2 bytes after buf */
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len = b32->encode(buf + 2, &buflen, hdr, 3);
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if (len != 5)
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warnx("mismatch in encoded upstream header length! expected 5, got %lu", len);
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code = (f->ack_other & 1) << 4 | ((f->ack_other < 0 ? 0 : 1) << 3) | (f->is_nack << 2) | (f->start << 1) | f->end;
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buf[5] = b32_5to8(code); /* Fifth byte is 1 bit downstream ACK, bit flags isACK, isNACK, first, last */
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/* Encode data into buf after header (6 = user + CMC + 4 bytes header) */
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build_hostname(buf, sizeof(buf), f->data, f->len, topdomain,
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dataenc, hostname_maxlen, 6);
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datacmc++;
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if (datacmc >= 36)
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datacmc = 0;
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send_query(fd, (char *)buf);
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send_query(fd, buf);
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window_tick(outbuf);
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}
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@ -477,8 +494,8 @@ write_dns_error(struct query *q, int ignore_some_errors)
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}
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}
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static int
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dns_namedec(char *outdata, int outdatalen, char *buf, int buflen)
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static size_t
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dns_namedec(uint8_t *outdata, size_t outdatalen, uint8_t *buf, size_t buflen)
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/* Decodes *buf to *outdata.
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* *buf WILL be changed by undotify.
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* Note: buflen must be _exactly_ strlen(buf) before undotifying.
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@ -496,8 +513,7 @@ dns_namedec(char *outdata, int outdatalen, char *buf, int buflen)
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return 0;
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/* this also does undotify */
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return unpack_data(outdata, outdatalen, buf + 1, buflen - 4,
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b32);
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return unpack_data(outdata, outdatalen, buf + 1, buflen - 4, b32);
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case 'i': /* Hostname++ with base64 */
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case 'I':
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@ -506,8 +522,7 @@ dns_namedec(char *outdata, int outdatalen, char *buf, int buflen)
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return 0;
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/* this also does undotify */
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return unpack_data(outdata, outdatalen, buf + 1, buflen - 4,
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b64);
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return unpack_data(outdata, outdatalen, buf + 1, buflen - 4, b64);
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case 'j': /* Hostname++ with base64u */
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case 'J':
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@ -516,8 +531,7 @@ dns_namedec(char *outdata, int outdatalen, char *buf, int buflen)
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return 0;
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/* this also does undotify */
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return unpack_data(outdata, outdatalen, buf + 1, buflen - 4,
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b64u);
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return unpack_data(outdata, outdatalen, buf + 1, buflen - 4, b64u);
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case 'k': /* Hostname++ with base128 */
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case 'K':
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@ -526,8 +540,7 @@ dns_namedec(char *outdata, int outdatalen, char *buf, int buflen)
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return 0;
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/* this also does undotify */
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return unpack_data(outdata, outdatalen, buf + 1, buflen - 4,
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b128);
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return unpack_data(outdata, outdatalen, buf + 1, buflen - 4, b128);
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case 't': /* plain base32(Thirty-two) from TXT */
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case 'T':
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@ -575,7 +588,7 @@ dns_namedec(char *outdata, int outdatalen, char *buf, int buflen)
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}
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static int
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read_dns_withq(int dns_fd, int tun_fd, char *buf, int buflen, struct query *q)
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read_dns_withq(int dns_fd, int tun_fd, uint8_t *buf, size_t buflen, struct query *q)
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/* Returns -1 on receive error or decode error, including DNS error replies.
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Returns 0 on replies that could be correct but are useless, and are not
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DNS error replies.
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@ -583,7 +596,7 @@ read_dns_withq(int dns_fd, int tun_fd, char *buf, int buflen, struct query *q)
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*/
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{
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struct sockaddr_storage from;
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char data[64*1024];
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uint8_t data[64*1024];
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socklen_t addrlen;
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int r;
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@ -600,7 +613,7 @@ read_dns_withq(int dns_fd, int tun_fd, char *buf, int buflen, struct query *q)
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/* useless packet */
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return 0;
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rv = dns_decode(buf, buflen, q, QR_ANSWER, data, r);
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rv = dns_decode((char *)buf, buflen, q, QR_ANSWER, (char *)data, r);
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if (rv <= 0)
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return rv;
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@ -630,7 +643,7 @@ read_dns_withq(int dns_fd, int tun_fd, char *buf, int buflen, struct query *q)
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int thispartlen, dataspace, datanew;
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while (1) {
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thispartlen = strlen(buf);
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thispartlen = strlen((char *)buf);
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thispartlen = MIN(thispartlen, buftotal-bufoffset);
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dataspace = sizeof(data) - dataoffset;
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if (thispartlen <= 0 || dataspace <= 0)
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@ -681,7 +694,7 @@ read_dns_withq(int dns_fd, int tun_fd, char *buf, int buflen, struct query *q)
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}
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static int
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handshake_waitdns(int dns_fd, char *buf, int buflen, char c1, char c2, int timeout)
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handshake_waitdns(int dns_fd, char *buf, size_t buflen, char c1, char c2, int timeout)
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/* Wait for DNS reply fitting to our latest query and returns it.
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Returns length of reply = #bytes used in buf.
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Returns 0 if fitting reply happens to be useless.
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@ -713,12 +726,11 @@ handshake_waitdns(int dns_fd, char *buf, int buflen, char c1, char c2, int timeo
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q.id = 0;
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q.name[0] = '\0';
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rv = read_dns_withq(dns_fd, 0, buf, buflen, &q);
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rv = read_dns_withq(dns_fd, 0, (uint8_t *)buf, buflen, &q);
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if (q.id != chunkid || (q.name[0] != c1 && q.name[0] != c2)) {
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#if 0
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fprintf(stderr, "Ignoring unfitting reply id %d starting with '%c'\n", q.id, q.name[0]);
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#endif
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if (debug >= 1)
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fprintf(stderr, "Ignoring unfitting reply id %d starting with '%c'\n", q.id, q.name[0]);
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continue;
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}
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@ -766,34 +778,37 @@ handshake_waitdns(int dns_fd, char *buf, int buflen, char c1, char c2, int timeo
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static int
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parse_data(uint8_t *data, size_t len, fragment *f)
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{
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size_t headerlen = DOWNSTREAM_HDR;
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memset(f, 0, sizeof(fragment));
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int ping = (data[3] >> 5) & 1;
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if (!ping) {
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f->seqID = data[0];
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f->start = data[3] & 1;
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f->end = (data[3] >> 1) & 1;
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f->is_nack = (data[3] >> 2) & 1;
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f->ack_other = (data[3] >> 3) & 1 ? data[1] : -1;
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f->compressed = (data[3] >> 4) & 1;
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f->len = len - 3;
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memcpy(f->data, data + 3, MIN(f->len, sizeof(f->data)));
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} else { /* Handle ping stuff */
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if (len != 5) return 1; /* invalid packet - continue */
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// static unsigned in_start_seq, out_start_seq, in_wsize, out_wsize;
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// out_start_seq = data[0];
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// in_start_seq = data[1];
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// in_wsize = data[3];
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// out_wsize = data[4];
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warnx("Pingy thingy received.");
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// TODO: handle pings
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int ping = (data[2] >> 5) & 1;
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f->compressed = (data[2] >> 4) & 1;
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f->ack_other = (data[2] >> 3) & 1 ? data[1] : -1;
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f->is_nack = (data[2] >> 2) & 1;
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f->start = (data[2] >> 1) & 1;
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f->end = data[2] & 1;
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f->seqID = data[0];
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if (ping) { /* Handle ping stuff */
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headerlen = DOWNSTREAM_PING_HDR;
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if (len < headerlen) return -1; /* invalid packet - continue */
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/* Parse data/ping header */
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static unsigned dn_start_seq, up_start_seq, dn_wsize, up_wsize;
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dn_wsize = data[3]; /* TODO: do something with wsize/start params in ping */
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up_wsize = data[4];
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dn_start_seq = data[5];
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up_start_seq = data[6];
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if (debug >= 3)
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fprintf(stderr, "PING pkt data=%lu WS: up=%u, dn=%u; Start: up=%u, dn=%u\n",
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len - headerlen, up_wsize, dn_wsize, up_start_seq, dn_start_seq);
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}
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f->len = len - headerlen;
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if (f->len > 0) memcpy(f->data, data + headerlen, MIN(f->len, sizeof(f->data)));
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return ping; /* return ping flag (if corresponding query was a ping) */
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}
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static int
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tunnel_tun(int tun_fd, int dns_fd)
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{
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size_t outlen, inlen;
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size_t outlen;
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uint8_t out[64*1024];
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uint8_t in[64*1024];
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ssize_t read;
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@ -801,20 +816,26 @@ tunnel_tun(int tun_fd, int dns_fd)
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if ((read = read_tun(tun_fd, in, sizeof(in))) <= 0)
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return -1;
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/* Give outgoing buffer all new data if it can hold it */
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if (window_buffer_available(outbuf) > read / MAX_FRAGSIZE)
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/* Check if outgoing buffer can hold data */
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if (window_buffer_available(outbuf) < (read / MAX_FRAGSIZE) + 1) {
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if (debug >= 3)
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fprintf(stderr, " Outgoing buffer full (%lu/%lu), not adding data!\n", outbuf->numitems, outbuf->length);
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return -1;
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}
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if (debug >= 2)
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fprintf(stderr, " IN: %lu bytes on tunnel\n", read);
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outlen = sizeof(out);
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inlen = read;
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compress2(out, &outlen, in, inlen, 9);
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compress2(out, &outlen, in, read, 9);
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window_add_outgoing_data(outbuf, out, outlen, 1);
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if (conn == CONN_DNS_NULL) {
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send_next_frag(dns_fd);
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send_ping_soon = 0;
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// TODO: adjust min send interval based on DNS server droppiness
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send_ping_soon = is_sending() ? 2 : 0;
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} else {
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send_raw_data(dns_fd);
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}
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@ -829,7 +850,7 @@ tunnel_dns(int tun_fd, int dns_fd)
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static long packrecv_oos = 0;
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static long packrecv_servfail = 0;
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static struct query q;
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size_t datalen;
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size_t datalen, buflen;
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static uint8_t buf[64*1024], cbuf[64*1024];
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static fragment f;
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int read, compressed, res;
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@ -838,15 +859,13 @@ tunnel_dns(int tun_fd, int dns_fd)
|
||||
memset(&q, 0, sizeof(q));
|
||||
memset(buf, 0, sizeof(buf));
|
||||
memset(cbuf, 0, sizeof(cbuf));
|
||||
read = read_dns_withq(dns_fd, tun_fd, (char *)cbuf, sizeof(cbuf), &q);
|
||||
read = read_dns_withq(dns_fd, tun_fd, cbuf, sizeof(cbuf), &q);
|
||||
|
||||
if (conn != CONN_DNS_NULL)
|
||||
return 1; /* everything already done */
|
||||
|
||||
#if 0
|
||||
fprintf(stderr, " Recv: id %5d name[0]='%c'\n",
|
||||
q.id, q.name[0]);
|
||||
#endif
|
||||
if (debug >= 2)
|
||||
fprintf(stderr, "RX: id %5d name[0]='%c'\n", q.id, q.name[0]);
|
||||
|
||||
/* Don't process anything that isn't data for us; usually error
|
||||
replies from fragsize probes etc. However a sequence of those,
|
||||
@ -859,7 +878,7 @@ tunnel_dns(int tun_fd, int dns_fd)
|
||||
return -1; /* nothing done */
|
||||
}
|
||||
|
||||
if (read < 3) {
|
||||
if (read < DOWNSTREAM_HDR) {
|
||||
/* Maybe SERVFAIL etc. Send ping to get things back in order,
|
||||
but wait a bit to prevent fast ping-pong loops. */
|
||||
|
||||
@ -883,14 +902,6 @@ tunnel_dns(int tun_fd, int dns_fd)
|
||||
}
|
||||
}
|
||||
|
||||
/* read==1 happens with "QMEM" illegal replies, caused by
|
||||
heavy reordering, or after short disconnections when
|
||||
data-CMC has looped around into the "duplicate" values.
|
||||
All these cases are helped by faster pinging. */
|
||||
#if 0
|
||||
if (read == 1)
|
||||
fprintf(stderr, " q=%c id %5d 1-byte illegal \"QMEM\" reply\n", q.name[0], q.id);
|
||||
#endif
|
||||
send_ping_soon = 900;
|
||||
return -1; /* nothing done */
|
||||
}
|
||||
@ -905,13 +916,17 @@ tunnel_dns(int tun_fd, int dns_fd)
|
||||
send_ping_soon = 0;
|
||||
}
|
||||
|
||||
/* Okay, we have a recent downstream packet */
|
||||
lastdownstreamtime = time(NULL);
|
||||
if (!(packrecv & 0x1000000))
|
||||
packrecv++;
|
||||
send_query_recvcnt++; /* overflow doesn't matter */
|
||||
|
||||
/* Decode the downstream data header and fragment-ify ready for processing */
|
||||
res = parse_data(cbuf, read, &f);
|
||||
|
||||
/* if this response was a reverse ping/response to a ping, we need to do something */
|
||||
if (res) {
|
||||
goto skip_recv;
|
||||
}
|
||||
if ((debug >= 3 && res) || (debug >= 2 && !res))
|
||||
fprintf(stderr, " RX %s frag id %u, ACK %d, nack %d, datalen %lu, s%d e%d\n",
|
||||
res ? "PING" : "DATA", f.seqID, f.ack_other, f.is_nack, f.len, f.start, f.end);
|
||||
|
||||
window_ack(outbuf, f.ack_other);
|
||||
|
||||
@ -919,19 +934,16 @@ tunnel_dns(int tun_fd, int dns_fd)
|
||||
query, only during heavy data transfer. Since this means the server
|
||||
doesn't have any packets to send, send one relatively fast (but not
|
||||
too fast, to avoid runaway ping-pong loops..) */
|
||||
/* Don't send anything too soon; no data waiting from server */
|
||||
if (f.len == 0) {
|
||||
if (!res && debug >= 1)
|
||||
fprintf(stderr, "Received downstream data with 0 length and NOT a ping!");
|
||||
send_ping_soon = 700;
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* Get next ACK if nothing already pending */
|
||||
if (next_downstream_ack < 0) {
|
||||
if ((next_downstream_ack = window_get_next_ack(inbuf)) < 0) {
|
||||
next_downstream_ack = -1;
|
||||
} else {
|
||||
send_something_now = 1;
|
||||
}
|
||||
}
|
||||
/* Send something quickly to see if any more data needs to come through */
|
||||
send_ping_soon = 5;
|
||||
|
||||
/* Downstream data traffic */
|
||||
if (!window_process_incoming_fragment(inbuf, &f)) {
|
||||
@ -940,40 +952,38 @@ tunnel_dns(int tun_fd, int dns_fd)
|
||||
return -1; /* nothing done */
|
||||
}
|
||||
|
||||
// TODO: check OOS packet count and send ping to update params
|
||||
/* Get next ACK if nothing already pending: only do this if we are sending */
|
||||
if (next_downstream_ack < 0) {
|
||||
if ((next_downstream_ack = window_get_next_ack(inbuf)) >= 0) {
|
||||
send_something_now = 1;
|
||||
}
|
||||
}
|
||||
|
||||
/* Okay, we have a recent downstream packet */
|
||||
lastdownstreamtime = time(NULL);
|
||||
if (!(packrecv & 0x1000000))
|
||||
packrecv++;
|
||||
send_query_recvcnt++; /* overflow doesn't matter */
|
||||
// TODO: check OOS packet count and send ping to update params
|
||||
|
||||
datalen = window_reassemble_data(inbuf, cbuf, sizeof(cbuf), &compressed);
|
||||
if (datalen != 0) {
|
||||
if (compressed) {
|
||||
if ((res = uncompress(buf, &datalen, cbuf, datalen)) == Z_OK) {
|
||||
write_tun(tun_fd, buf, datalen);
|
||||
} else {
|
||||
warnx("Uncompress failed (%d): reassembled data corrupted or incomplete!", res);
|
||||
buflen = sizeof(buf);
|
||||
if ((res = uncompress(buf, &buflen, cbuf, datalen)) != Z_OK) {
|
||||
if (debug >= 1)
|
||||
warnx("Uncompress failed (%d): reassembled data corrupted or incomplete!", res);
|
||||
}
|
||||
send_ping_soon = 5;
|
||||
datalen = buflen;
|
||||
}
|
||||
write_tun(tun_fd, buf, datalen);
|
||||
/* ACK frag quickly */
|
||||
send_ping_soon = 2;
|
||||
} else {
|
||||
/* Send anything to ack the received seqno/frag, and get more */
|
||||
/* was last frag; wait just a trifle because our
|
||||
tun will probably return TCP-ack immediately.
|
||||
5msec = 200 DNSreq/sec */
|
||||
/* server certainly has more data */
|
||||
/* ACK received frag and let server send any more data */
|
||||
send_something_now = 1;
|
||||
}
|
||||
|
||||
skip_recv:
|
||||
/* Move window along after doing all data processing */
|
||||
window_tick(inbuf);
|
||||
|
||||
/* NOTE: buf[] was overwritten when down-packet complete */
|
||||
/* Upstream data traffic */
|
||||
if (is_sending()) {
|
||||
if (is_sending() || is_recving()) {
|
||||
/* More to send - next fragment*/
|
||||
send_next_frag(dns_fd);
|
||||
send_ping_soon = 2;
|
||||
@ -982,7 +992,8 @@ tunnel_dns(int tun_fd, int dns_fd)
|
||||
|
||||
/* Send ping if we didn't send anything yet */
|
||||
if (send_something_now) {
|
||||
send_ping(dns_fd, 0);
|
||||
send_ping(dns_fd, 0, next_downstream_ack);
|
||||
next_downstream_ack = -1;
|
||||
send_ping_soon = 0;
|
||||
}
|
||||
|
||||
@ -1006,9 +1017,15 @@ client_tunnel(int tun_fd, int dns_fd)
|
||||
tv.tv_usec = 0;
|
||||
|
||||
if (is_sending()) {
|
||||
/* fast timeout for retransmits */
|
||||
tv.tv_sec = 1;
|
||||
tv.tv_usec = 0;
|
||||
tv.tv_sec = 0;
|
||||
tv.tv_usec = 2000;
|
||||
send_ping_soon = 0;
|
||||
}
|
||||
|
||||
if (is_recving()) {
|
||||
/* get next thingy soon ish */
|
||||
tv.tv_sec = 0;
|
||||
tv.tv_usec = 5000;
|
||||
}
|
||||
|
||||
if (send_ping_soon) {
|
||||
@ -1017,10 +1034,9 @@ client_tunnel(int tun_fd, int dns_fd)
|
||||
}
|
||||
|
||||
FD_ZERO(&fds);
|
||||
if (window_buffer_available(outbuf) > 5 || 1) {
|
||||
if (window_buffer_available(outbuf) > 16) {
|
||||
/* Fill up outgoing buffer with available data
|
||||
* The windowing protocol manages data retransmits, timeouts etc.
|
||||
* TODO: is this even necessary? tunnel_tun seems to be more useful */
|
||||
* The windowing protocol manages data retransmits, timeouts etc. */
|
||||
FD_SET(tun_fd, &fds);
|
||||
}
|
||||
FD_SET(dns_fd, &fds);
|
||||
@ -1045,10 +1061,10 @@ client_tunnel(int tun_fd, int dns_fd)
|
||||
send_next_frag(dns_fd);
|
||||
} else {
|
||||
outbuf->resends = 0;
|
||||
send_ping(dns_fd, 1);
|
||||
send_ping(dns_fd, 1, -1);
|
||||
}
|
||||
} else {
|
||||
send_ping(dns_fd, 0);
|
||||
send_ping(dns_fd, 0, -1);
|
||||
}
|
||||
send_ping_soon = 0;
|
||||
|
||||
@ -1074,7 +1090,7 @@ client_tunnel(int tun_fd, int dns_fd)
|
||||
static void
|
||||
send_login(int fd, char *login, int len)
|
||||
{
|
||||
char data[19];
|
||||
uint8_t data[19];
|
||||
|
||||
memset(data, 0, sizeof(data));
|
||||
data[0] = userid;
|
||||
@ -1091,8 +1107,8 @@ send_login(int fd, char *login, int len)
|
||||
static void
|
||||
send_fragsize_probe(int fd, int fragsize)
|
||||
{
|
||||
char probedata[256];
|
||||
char buf[4096];
|
||||
uint8_t probedata[256];
|
||||
uint8_t buf[MAX_FRAGSIZE];
|
||||
|
||||
/*
|
||||
* build a large query domain which is random and maximum size,
|
||||
@ -1120,7 +1136,7 @@ send_fragsize_probe(int fd, int fragsize)
|
||||
static void
|
||||
send_set_downstream_fragsize(int fd, int fragsize)
|
||||
{
|
||||
char data[5];
|
||||
uint8_t data[5];
|
||||
|
||||
data[0] = userid;
|
||||
data[1] = (fragsize & 0xff00) >> 8;
|
||||
@ -1136,7 +1152,7 @@ send_set_downstream_fragsize(int fd, int fragsize)
|
||||
static void
|
||||
send_version(int fd, uint32_t version)
|
||||
{
|
||||
char data[6];
|
||||
uint8_t data[6];
|
||||
|
||||
data[0] = (version >> 24) & 0xff;
|
||||
data[1] = (version >> 16) & 0xff;
|
||||
@ -1154,7 +1170,7 @@ send_version(int fd, uint32_t version)
|
||||
static void
|
||||
send_ip_request(int fd, int userid)
|
||||
{
|
||||
char buf[512] = "i____.";
|
||||
uint8_t buf[512] = "i____.";
|
||||
buf[1] = b32_5to8(userid);
|
||||
|
||||
buf[2] = b32_5to8((rand_seed >> 10) & 0x1f);
|
||||
@ -1162,7 +1178,7 @@ send_ip_request(int fd, int userid)
|
||||
buf[4] = b32_5to8((rand_seed ) & 0x1f);
|
||||
rand_seed++;
|
||||
|
||||
strncat(buf, topdomain, 512 - strlen(buf));
|
||||
strncat((char *)buf, topdomain, 512 - strlen((char *)buf));
|
||||
send_query(fd, buf);
|
||||
}
|
||||
|
||||
@ -1189,7 +1205,7 @@ send_upenctest(int fd, char *s)
|
||||
strncat(buf, s, 512);
|
||||
strncat(buf, ".", 512);
|
||||
strncat(buf, topdomain, 512 - strlen(buf));
|
||||
send_query(fd, buf);
|
||||
send_query(fd, (uint8_t *)buf);
|
||||
}
|
||||
|
||||
static void
|
||||
@ -1207,7 +1223,7 @@ send_downenctest(int fd, char downenc, int variant, char *s, int slen)
|
||||
rand_seed++;
|
||||
|
||||
strncat(buf, topdomain, 512 - strlen(buf));
|
||||
send_query(fd, buf);
|
||||
send_query(fd, (uint8_t *)buf);
|
||||
}
|
||||
|
||||
static void
|
||||
@ -1223,7 +1239,7 @@ send_codec_switch(int fd, int userid, int bits)
|
||||
rand_seed++;
|
||||
|
||||
strncat(buf, topdomain, 512 - strlen(buf));
|
||||
send_query(fd, buf);
|
||||
send_query(fd, (uint8_t *)buf);
|
||||
}
|
||||
|
||||
|
||||
@ -1240,7 +1256,7 @@ send_downenc_switch(int fd, int userid)
|
||||
rand_seed++;
|
||||
|
||||
strncat(buf, topdomain, 512 - strlen(buf));
|
||||
send_query(fd, buf);
|
||||
send_query(fd, (uint8_t *)buf);
|
||||
}
|
||||
|
||||
static void
|
||||
@ -1260,7 +1276,7 @@ send_lazy_switch(int fd, int userid)
|
||||
rand_seed++;
|
||||
|
||||
strncat(buf, topdomain, 512 - strlen(buf));
|
||||
send_query(fd, buf);
|
||||
send_query(fd, (uint8_t *)buf);
|
||||
}
|
||||
|
||||
static int
|
||||
@ -1285,7 +1301,7 @@ handshake_version(int dns_fd, int *seed)
|
||||
((in[6] & 0xff) << 8) |
|
||||
((in[7] & 0xff)));
|
||||
|
||||
if (strncmp("VACK", in, 4) == 0) {
|
||||
if (strncmp("VACK", (char *)in, 4) == 0) {
|
||||
*seed = payload;
|
||||
userid = in[8];
|
||||
userid_char = hex[userid & 15];
|
||||
@ -1294,11 +1310,11 @@ handshake_version(int dns_fd, int *seed)
|
||||
fprintf(stderr, "Version ok, both using protocol v 0x%08x. You are user #%d\n",
|
||||
PROTOCOL_VERSION, userid);
|
||||
return 0;
|
||||
} else if (strncmp("VNAK", in, 4) == 0) {
|
||||
} else if (strncmp("VNAK", (char *)in, 4) == 0) {
|
||||
warnx("You use protocol v 0x%08x, server uses v 0x%08x. Giving up",
|
||||
PROTOCOL_VERSION, payload);
|
||||
return 1;
|
||||
} else if (strncmp("VFUL", in, 4) == 0) {
|
||||
} else if (strncmp("VFUL", (char *)in, 4) == 0) {
|
||||
warnx("Server full, all %d slots are taken. Try again later", payload);
|
||||
return 1;
|
||||
}
|
||||
@ -1483,13 +1499,6 @@ handshake_upenctest(int dns_fd, char *s)
|
||||
|
||||
if (read > 0) {
|
||||
int k;
|
||||
#if 0
|
||||
/* in[56] = '@'; */
|
||||
/* in[56] = '_'; */
|
||||
/* if (in[29] == '\344') in[29] = 'a'; */
|
||||
in[read] = '\0';
|
||||
fprintf(stderr, "BounceReply: >%s<\n", in);
|
||||
#endif
|
||||
/* quick check if case swapped, to give informative error msg */
|
||||
if (in[4] == 'A') {
|
||||
fprintf(stderr, "DNS queries get changed to uppercase, keeping upstream codec Base32\n");
|
||||
@ -1808,10 +1817,8 @@ handshake_qtype_autodetect(int dns_fd)
|
||||
if (handshake_qtypetest(dns_fd, timeout)) {
|
||||
/* okay */
|
||||
highestworking = qtypenum;
|
||||
#if 0
|
||||
fprintf(stderr, " Type %s timeout %d works\n",
|
||||
client_get_qtype(), timeout);
|
||||
#endif
|
||||
if (debug >= 1)
|
||||
fprintf(stderr, " Type %s timeout %d works\n", client_get_qtype(), timeout);
|
||||
break;
|
||||
/* try others with longer timeout */
|
||||
}
|
||||
@ -1922,13 +1929,13 @@ handshake_switch_codec(int dns_fd, int bits)
|
||||
|
||||
if (read > 0) {
|
||||
if (strncmp("BADLEN", in, 6) == 0) {
|
||||
fprintf(stderr, "Server got bad message length. ");
|
||||
fprintf(stderr, "Server got bad message length.\n");
|
||||
goto codec_revert;
|
||||
} else if (strncmp("BADIP", in, 5) == 0) {
|
||||
fprintf(stderr, "Server rejected sender IP address. ");
|
||||
fprintf(stderr, "Server rejected sender IP address.\n");
|
||||
goto codec_revert;
|
||||
} else if (strncmp("BADCODEC", in, 8) == 0) {
|
||||
fprintf(stderr, "Server rejected the selected codec. ");
|
||||
fprintf(stderr, "Server rejected the selected codec.\n");
|
||||
goto codec_revert;
|
||||
}
|
||||
in[read] = 0; /* zero terminate */
|
||||
@ -1936,7 +1943,7 @@ handshake_switch_codec(int dns_fd, int bits)
|
||||
dataenc = tempenc;
|
||||
|
||||
/* Update outgoing buffer max (decoded) fragsize */
|
||||
outbuf->maxfraglen = get_raw_length(hostname_maxlen, dataenc, topdomain);
|
||||
outbuf->maxfraglen = get_raw_length_from_dns(hostname_maxlen - UPSTREAM_HDR, dataenc, topdomain);
|
||||
return;
|
||||
}
|
||||
|
||||
@ -1945,7 +1952,7 @@ handshake_switch_codec(int dns_fd, int bits)
|
||||
if (!running)
|
||||
return;
|
||||
|
||||
fprintf(stderr, "No reply from server on codec switch. ");
|
||||
fprintf(stderr, "No reply from server on codec switch.\n");
|
||||
|
||||
codec_revert:
|
||||
fprintf(stderr, "Falling back to upstream codec %s\n", dataenc->name);
|
||||
@ -1978,13 +1985,13 @@ handshake_switch_downenc(int dns_fd)
|
||||
|
||||
if (read > 0) {
|
||||
if (strncmp("BADLEN", in, 6) == 0) {
|
||||
fprintf(stderr, "Server got bad message length. ");
|
||||
fprintf(stderr, "Server got bad message length.\n");
|
||||
goto codec_revert;
|
||||
} else if (strncmp("BADIP", in, 5) == 0) {
|
||||
fprintf(stderr, "Server rejected sender IP address. ");
|
||||
fprintf(stderr, "Server rejected sender IP address.\n");
|
||||
goto codec_revert;
|
||||
} else if (strncmp("BADCODEC", in, 8) == 0) {
|
||||
fprintf(stderr, "Server rejected the selected codec. ");
|
||||
fprintf(stderr, "Server rejected the selected codec.\n");
|
||||
goto codec_revert;
|
||||
}
|
||||
in[read] = 0; /* zero terminate */
|
||||
@ -1997,7 +2004,7 @@ handshake_switch_downenc(int dns_fd)
|
||||
if (!running)
|
||||
return;
|
||||
|
||||
fprintf(stderr, "No reply from server on codec switch. ");
|
||||
fprintf(stderr, "No reply from server on codec switch.\n");
|
||||
|
||||
codec_revert:
|
||||
fprintf(stderr, "Falling back to downstream codec Base32\n");
|
||||
@ -2019,13 +2026,13 @@ handshake_try_lazy(int dns_fd)
|
||||
|
||||
if (read > 0) {
|
||||
if (strncmp("BADLEN", in, 6) == 0) {
|
||||
fprintf(stderr, "Server got bad message length. ");
|
||||
fprintf(stderr, "Server got bad message length.\n");
|
||||
goto codec_revert;
|
||||
} else if (strncmp("BADIP", in, 5) == 0) {
|
||||
fprintf(stderr, "Server rejected sender IP address. ");
|
||||
fprintf(stderr, "Server rejected sender IP address.\n");
|
||||
goto codec_revert;
|
||||
} else if (strncmp("BADCODEC", in, 8) == 0) {
|
||||
fprintf(stderr, "Server rejected lazy mode. ");
|
||||
fprintf(stderr, "Server rejected lazy mode.\n");
|
||||
goto codec_revert;
|
||||
} else if (strncmp("Lazy", in, 4) == 0) {
|
||||
fprintf(stderr, "Server switched to lazy mode\n");
|
||||
@ -2039,7 +2046,7 @@ handshake_try_lazy(int dns_fd)
|
||||
if (!running)
|
||||
return;
|
||||
|
||||
fprintf(stderr, "No reply from server on lazy switch. ");
|
||||
fprintf(stderr, "No reply from server on lazy switch.\n");
|
||||
|
||||
codec_revert:
|
||||
fprintf(stderr, "Falling back to legacy mode\n");
|
||||
@ -2062,7 +2069,7 @@ handshake_lazyoff(int dns_fd)
|
||||
read = handshake_waitdns(dns_fd, in, sizeof(in), 'o', 'O', 1);
|
||||
|
||||
if (read == 9 && strncmp("Immediate", in, 9) == 0) {
|
||||
warnx("Server switched back to legacy mode.\n");
|
||||
warnx("Server switched back to legacy mode.");
|
||||
lazymode = 0;
|
||||
selecttimeout = 1;
|
||||
return;
|
||||
@ -2071,7 +2078,7 @@ handshake_lazyoff(int dns_fd)
|
||||
if (!running)
|
||||
return;
|
||||
|
||||
warnx("No reply from server on legacy mode switch.\n");
|
||||
warnx("No reply from server on legacy mode switch.");
|
||||
}
|
||||
|
||||
static int
|
||||
@ -2111,8 +2118,7 @@ fragsize_check(char *in, int read, int proposed_fragsize, int *max_fragsize)
|
||||
/* in[123] = 123; */
|
||||
|
||||
if ((in[2] & 0xff) != 107) {
|
||||
fprintf(stderr, "\n");
|
||||
warnx("corruption at byte 2, this won't work. Try -O Base32, or other -T options.");
|
||||
warnx("\ncorruption at byte 2, this won't work. Try -O Base32, or other -T options.");
|
||||
*max_fragsize = -1;
|
||||
return 1;
|
||||
}
|
||||
@ -2150,7 +2156,7 @@ fragsize_check(char *in, int read, int proposed_fragsize, int *max_fragsize)
|
||||
static int
|
||||
handshake_autoprobe_fragsize(int dns_fd)
|
||||
{
|
||||
char in[4096];
|
||||
char in[MAX_FRAGSIZE];
|
||||
int i;
|
||||
int read;
|
||||
int proposed_fragsize = 768;
|
||||
@ -2158,7 +2164,7 @@ handshake_autoprobe_fragsize(int dns_fd)
|
||||
int max_fragsize;
|
||||
|
||||
max_fragsize = 0;
|
||||
fprintf(stderr, "Autoprobing max downstream fragment size... (skip with -m fragsize)\n");
|
||||
fprintf(stderr, "Autoprobing max downstream fragment size... (skip with -m fragsize)");
|
||||
while (running && range > 0 && (range >= 8 || max_fragsize < 300)) {
|
||||
/* stop the slow probing early when we have enough bytes anyway */
|
||||
for (i=0; running && i<3 ;i++) {
|
||||
@ -2191,16 +2197,14 @@ handshake_autoprobe_fragsize(int dns_fd)
|
||||
}
|
||||
}
|
||||
if (!running) {
|
||||
fprintf(stderr, "\n");
|
||||
warnx("stopped while autodetecting fragment size (Try setting manually with -m)");
|
||||
warnx("\nstopped while autodetecting fragment size (Try setting manually with -m)");
|
||||
return 0;
|
||||
}
|
||||
if (max_fragsize <= 6) {
|
||||
/* Tried all the way down to 2 and found no good size.
|
||||
But we _did_ do all handshake before this, so there must
|
||||
be some workable connection. */
|
||||
fprintf(stderr, "\n");
|
||||
warnx("found no accepted fragment size.");
|
||||
warnx("\nfound no accepted fragment size.");
|
||||
warnx("try setting -M to 200 or lower, or try other -T or -O options.");
|
||||
return 0;
|
||||
}
|
||||
@ -2238,7 +2242,7 @@ handshake_set_fragsize(int dns_fd, int fragsize)
|
||||
if (read > 0) {
|
||||
|
||||
if (strncmp("BADFRAG", in, 7) == 0) {
|
||||
fprintf(stderr, "Server rejected fragsize. Keeping default.");
|
||||
fprintf(stderr, "Server rejected fragsize. Keeping default.\n");
|
||||
return;
|
||||
} else if (strncmp("BADIP", in, 5) == 0) {
|
||||
fprintf(stderr, "Server rejected sender IP address.\n");
|
||||
|
||||
@ -77,7 +77,9 @@ extern const unsigned char raw_header[RAW_HDR_LEN];
|
||||
/* Unused RR type, never actually sent */
|
||||
|
||||
#define DOWNSTREAM_HDR 3
|
||||
#define DOWNSTREAM_PING_HDR 7
|
||||
#define UPSTREAM_HDR 6
|
||||
#define UPSTREAM_PING 6
|
||||
|
||||
struct query {
|
||||
char name[QUERY_NAME_SIZE];
|
||||
|
||||
Loading…
Reference in New Issue
Block a user