mirror of
https://github.com/yarrick/iodine.git
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More unsignedness and working DNS tunnelling
This commit is contained in:
frekky
parent
51a59bed24
commit
98da57ba74
618
src/server.c
618
src/server.c
@ -181,7 +181,8 @@ save_to_qmem_pingordata(int userid, struct query *q)
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+ 1 char CMC; that last char is non-Base32.
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*/
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char cmc[8];
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warnx("save_to_qmem_pingordata deprecated! use something else instead!");
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uint8_t cmc[8];
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int i;
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if (q->name[0] == 'P' || q->name[0] == 'p') {
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@ -195,15 +196,15 @@ save_to_qmem_pingordata(int userid, struct query *q)
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/* We already unpacked in handle_null_request(), but that's
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lost now... Note: b32 directly, we want no undotify here! */
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i = b32->decode(cmc, &cmcsize, q->name + 1, (cp - q->name) - 1);
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i = b32->decode(cmc, &cmcsize, (uint8_t *)q->name + 1, (cp - q->name) - 1);
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if (i < 4)
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return; /* illegal ping; shouldn't happen */
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save_to_qmem(users[userid].qmemping_cmc,
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/*save_to_qmem(users[userid].qmemping_cmc,
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users[userid].qmemping_type, QMEMPING_LEN,
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&users[userid].qmemping_lastfilled,
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(void *) cmc, q->type);
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(void *) cmc, q->type);*/
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} else {
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/* Data packet, hopefully not illegal */
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if (strlen(q->name) < 5)
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@ -220,10 +221,10 @@ save_to_qmem_pingordata(int userid, struct query *q)
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else
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cmc[i] = q->name[i+1];
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save_to_qmem(users[userid].qmemdata_cmc,
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/*save_to_qmem(users[userid].qmemdata_cmc,
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users[userid].qmemdata_type, QMEMDATA_LEN,
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&users[userid].qmemdata_lastfilled,
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(void *) cmc, q->type);
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(void *) cmc, q->type);*/
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}
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}
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@ -231,7 +232,8 @@ static inline int
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answer_from_qmem_data(int dns_fd, int userid, struct query *q)
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/* Quick helper function to keep handle_null_request() clean */
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{
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char cmc[4];
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warnx("answer_from_qmem_data deprecated! use something else");
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/*char cmc[4];
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int i;
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for (i = 0; i < 4; i++)
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@ -242,7 +244,8 @@ answer_from_qmem_data(int dns_fd, int userid, struct query *q)
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return answer_from_qmem(dns_fd, q, users[userid].qmemdata_cmc,
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users[userid].qmemdata_type, QMEMDATA_LEN,
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(void *) cmc);
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(void *) cmc);*/
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return 0;
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}
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/* END INLINE FUNCTION DEFINITIONS */
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@ -260,7 +263,7 @@ answer_from_qmem_data(int dns_fd, int userid, struct query *q)
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are prevented. Data-CMC is only 36 counts, so our cache length should
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not exceed 36/2=18 packets. (This quick rule assumes all packets are
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otherwise equal, which they arent: up/downstream seq, TCP/IP headers and
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the actual data) TODO: adjust dns cache length
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the actual data
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*/
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static void
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@ -370,40 +373,8 @@ forward_query(int bind_fd, struct query *q)
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}
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}
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void
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send_ping_response(int dns_fd, int userid, struct query *q)
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{
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static uint8_t pkt[10];
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size_t datalen = 5;
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/* Build downstream data + ping header (see doc/proto_xxxxxxxx.txt) for details */
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pkt[0] = users[userid].outgoing->start_seq_id & 0xFF;
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pkt[1] = users[userid].incoming->start_seq_id & 0xFF;
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pkt[2] = (1 << 5); /* ping flag */
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pkt[3] = users[userid].outgoing->windowsize & 0xFF;
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pkt[4] = users[userid].incoming->windowsize & 0xFF;
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write_dns(dns_fd, q, (char *)pkt, datalen, users[userid].downenc);
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if (q->id2 != 0) { /* rotate pending duplicate queries */
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q->id = q->id2;
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q->fromlen = q->fromlen2;
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memcpy(&(q->from), &(q->from2), q->fromlen2);
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if (debug >= 1)
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warnx("OUT again to last duplicate");
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write_dns(dns_fd, q, (char *)pkt, datalen, users[userid].downenc);
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}
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save_to_qmem_pingordata(userid, q);
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#ifdef DNSCACHE_LEN
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save_to_dnscache(userid, q, (char *)pkt, datalen + 2);
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#endif
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q->id = 0; /* this query is used */
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}
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static int
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send_frag_or_dataless(int dns_fd, int userid, struct query *q)
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send_frag_or_dataless(int dns_fd, int userid, struct query *q, int ping)
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/* Sends current fragment to user, or a ping if no data available.
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Does not update anything, except:
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- discards q always (query is used)
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@ -413,55 +384,57 @@ send_frag_or_dataless(int dns_fd, int userid, struct query *q)
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0 = don't call us again for now.
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*/
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{
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static uint8_t pkt[MAX_FRAGSIZE + DOWNSTREAM_HDR];
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int ping = 0;
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size_t datalen;
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static uint8_t pkt[MAX_FRAGSIZE + DOWNSTREAM_PING_HDR];
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size_t datalen, headerlen;
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fragment *f;
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struct frag_buffer *out;
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struct frag_buffer *out, *in;
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in = users[userid].incoming;
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out = users[userid].outgoing;
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f = window_get_next_sending_fragment(out, users[userid].next_upstream_ack);
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if (!f && user_sending(userid)) {
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/* Need to tell client to sync stuff - send data header with ping stuff */
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f = window_get_next_sending_fragment(out, &users[userid].next_upstream_ack);
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if (!f) {
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/* No data, may as well send data/ping header (with extra info) */
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ping = 1;
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} /* TODO: If re-sent too many times, drop stuff */
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/* Build downstream data header (see doc/proto_xxxxxxxx.txt) for details */
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pkt[0] = f->seqID & 0xFF;
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pkt[1] = f->ack_other & 0xFF;
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pkt[2] = ((ping & 1) << 5) | ((f->compressed & 1) << 4) | ((f->ack_other < 0 ? 0 : 1) << 3)
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| (f->is_nack << 2) | (f->start << 1) | f->end;
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if (ping) {
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pkt[3] = out->windowsize & 0xFF;
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pkt[4] = users[userid].incoming->windowsize & 0xFF;
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datalen = 5;
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datalen = 0;
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pkt[0] = 0; /* Pings don't need seq IDs unless they have data */
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pkt[1] = users[userid].next_upstream_ack & 0xFF;
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pkt[2] = (1 << 5) | ((users[userid].next_upstream_ack < 0 ? 0 : 1) << 3);
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/* TODO: resend ACKs in pings? */
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users[userid].next_upstream_ack = -1;
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} else {
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datalen = DOWNSTREAM_HDR + f->len;
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if (datalen > sizeof(pkt)) {
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warnx("send_frag_or_dataless: fragment too large to send!");
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return 0;
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}
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memcpy(&pkt, f->data, f->len);
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}
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write_dns(dns_fd, q, (char *)pkt, datalen, users[userid].downenc);
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if (q->id2 != 0) { /* reply to any duplicates */
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q->id = q->id2;
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q->fromlen = q->fromlen2;
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memcpy(&(q->from), &(q->from2), q->fromlen2);
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if (debug >= 1)
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warnx("OUT again to last duplicate");
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write_dns(dns_fd, q, (char *)pkt, datalen, users[userid].downenc);
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datalen = f->len;
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pkt[0] = f->seqID & 0xFF;
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pkt[1] = f->ack_other & 0xFF;
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pkt[2] = ((f->compressed & 1) << 4) | ((f->ack_other < 0 ? 0 : 1) << 3) |
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(f->is_nack << 2) | (f->start << 1) | f->end;
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headerlen = DOWNSTREAM_HDR;
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}
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save_to_qmem_pingordata(userid, q);
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/* Build downstream data/ping header (see doc/proto_xxxxxxxx.txt) for details */
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if (ping) { /* TODO: pings with downstream data */
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pkt[3] = out->windowsize & 0xFF;
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pkt[4] = in->windowsize & 0xFF;
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pkt[5] = out->start_seq_id & 0xFF;
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pkt[6] = in->start_seq_id & 0xFF;
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headerlen = DOWNSTREAM_PING_HDR;
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}
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if (datalen + headerlen > sizeof(pkt)) {
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warnx("send_frag_or_dataless: fragment too large to send! (%lu)", datalen);
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return 0;
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}
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if (f) memcpy(pkt + headerlen, f->data, datalen);
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write_dns(dns_fd, q, (char *)pkt, datalen + headerlen, users[userid].downenc);
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/* TODO: reply to any duplicates (q.id2 etc) */
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// save_to_qmem_pingordata(userid, q);
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#ifdef DNSCACHE_LEN
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save_to_dnscache(userid, q, (char *)pkt, datalen + 2);
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#endif
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/* this query has been */
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/* this query has been used */
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q->id = 0;
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window_tick(out);
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@ -569,14 +542,8 @@ tunnel_tun(int tun_fd, struct dnsfd *dns_fds)
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window_add_outgoing_data(users[userid].outgoing, out, outlen, 1);
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/* Start sending immediately if query is waiting */
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if (users[userid].q_sendrealsoon.id != 0) {
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int dns_fd = get_dns_fd(dns_fds, &users[userid].q_sendrealsoon.from);
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send_frag_or_dataless(dns_fd, userid, &users[userid].q_sendrealsoon);
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} else if (users[userid].q.id != 0) {
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int dns_fd = get_dns_fd(dns_fds, &users[userid].q.from);
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send_frag_or_dataless(dns_fd, userid, &users[userid].q);
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}
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/* TODO: Start sending immediately if query is waiting
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* Need to get incoming query handling done first. */
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return outlen;
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} else { /* CONN_RAW_UDP */
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@ -598,8 +565,8 @@ tunnel_dns(int tun_fd, int dns_fd, struct dnsfd *dns_fds, int bind_fd)
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return 0;
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if (debug >= 2) {
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fprintf(stderr, "RX: client %s, type %d, name %s\n",
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format_addr(&q.from, q.fromlen), q.type, q.name);
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fprintf(stderr, "RX: client %s ID %5d, type %d, name %s\n",
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format_addr(&q.from, q.fromlen), q.id, q.type, q.name);
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}
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domain_len = strlen(q.name) - strlen(topdomain);
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@ -653,7 +620,7 @@ tunnel_dns(int tun_fd, int dns_fd, struct dnsfd *dns_fds, int bind_fd)
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} else {
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/* Forward query to other port ? */
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if (debug >= 3) {
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fprintf(stderr, "Requested domain outside our topdomain.");
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fprintf(stderr, "Requested domain outside our topdomain.\n");
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}
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if (bind_fd) {
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forward_query(bind_fd, &q);
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@ -673,26 +640,9 @@ server_tunnel(int tun_fd, struct dnsfd *dns_fds, int bind_fd, int max_idle_time)
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while (running) {
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int maxfd;
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tv.tv_sec = 10; /* doesn't really matter */
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tv.tv_sec = 5; /* TODO: adjust time based on query timeouts (lazy mode) */
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tv.tv_usec = 0;
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/* Adjust timeout if there is anything to send realsoon.
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Clients won't be sending new data until we send our ack, TODO: adjust stuff in this function
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so don't keep them waiting long. This only triggers at
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final upstream fragments, which is about once per eight
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requests during heavy upstream traffic.
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20msec: ~8 packets every 1/50sec = ~400 DNSreq/sec,
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or ~1200bytes every 1/50sec = ~0.5 Mbit/sec upstream */
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for (userid = 0; userid < created_users; userid++) {
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if (user_active(userid)) {
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users[userid].q_sendrealsoon_new = 0;
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if (users[userid].q_sendrealsoon.id != 0) {
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tv.tv_sec = 0;
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tv.tv_usec = 20000;
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}
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}
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}
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FD_ZERO(&fds);
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maxfd = 0;
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@ -754,14 +704,6 @@ server_tunnel(int tun_fd, struct dnsfd *dns_fds, int bind_fd, int max_idle_time)
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tunnel_bind(bind_fd, dns_fds);
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}
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}
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/* Send realsoon's if tun or dns didn't already */
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for (userid = 0; userid < created_users; userid++)
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if (user_active(userid) && users[userid].q_sendrealsoon.id != 0 &&
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users[userid].conn == CONN_DNS_NULL && !users[userid].q_sendrealsoon_new) {
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int dns_fd = get_dns_fd(dns_fds, &users[userid].q_sendrealsoon.from);
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send_frag_or_dataless(dns_fd, userid, &users[userid].q_sendrealsoon);
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}
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}
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return 0;
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@ -770,36 +712,25 @@ server_tunnel(int tun_fd, struct dnsfd *dns_fds, int bind_fd, int max_idle_time)
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void
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handle_full_packet(int tun_fd, struct dnsfd *dns_fds, int userid, uint8_t *data, size_t len)
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{
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unsigned long outlen;
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size_t outlen;
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uint8_t out[64*1024];
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struct ip *hdr;
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int touser;
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int ret;
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int ret; // TODO: optional upstream compression flag
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outlen = sizeof(out);
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if ((ret = uncompress(out, &outlen, data, len)) == Z_OK) {
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struct ip *hdr;
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hdr = (struct ip*) (out + 4);
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touser = find_user_by_ip(hdr->ip_dst.s_addr);
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if (debug >= 3)
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fprintf(stderr, "FULL PKT: %lu bytes from user %d (touser %d)\n", len, userid, touser);
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if (touser == -1) {
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/* send the uncompressed packet to tun device */
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write_tun(tun_fd, out, outlen);
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} else {
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/* send the compressed(!) packet to other client */
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/* send the compressed (!) packet to other client */
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if (users[touser].conn == CONN_DNS_NULL) {
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if (window_buffer_available(users[touser].outgoing) * users[touser].outgoing->maxfraglen >= len) {
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window_add_outgoing_data(users[touser].outgoing, data, len, 1);
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/* Start sending immediately if query is waiting */
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if (users[touser].q_sendrealsoon.id != 0) {
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int dns_fd = get_dns_fd(dns_fds, &users[touser].q_sendrealsoon.from);
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send_frag_or_dataless(dns_fd, touser, &users[touser].q_sendrealsoon);
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} else if (users[touser].q.id != 0) {
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int dns_fd = get_dns_fd(dns_fds, &users[touser].q.from);
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send_frag_or_dataless(dns_fd, touser, &users[touser].q);
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}
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}
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window_add_outgoing_data(users[touser].outgoing, data, len, 1);
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/* TODO: send immediately if query waiting */
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} else{ /* CONN_RAW_UDP */
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int dns_fd = get_dns_fd(dns_fds, &users[touser].q.from);
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send_raw(dns_fd, data, len, touser, RAW_HDR_CMD_DATA, &users[touser].q);
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@ -1002,13 +933,13 @@ read_dns(int fd, struct dnsfd *dns_fds, int tun_fd, struct query *q)
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}
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static size_t
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write_dns_nameenc(char *buf, size_t buflen, char *data, int datalen, char downenc)
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write_dns_nameenc(uint8_t *buf, size_t buflen, uint8_t *data, size_t datalen, char downenc)
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/* Returns #bytes of data that were encoded */
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{
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static int td1 = 0;
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static int td2 = 0;
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size_t space;
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char *b;
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uint8_t *b;
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/* Make a rotating topdomain to prevent filtering */
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td1+=3;
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@ -1057,7 +988,7 @@ write_dns_nameenc(char *buf, size_t buflen, char *data, int datalen, char downen
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/* Add dot (if it wasn't there already) and topdomain */
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b = buf;
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b += strlen(buf) - 1;
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b += strlen((char *)buf) - 1;
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if (*b != '.')
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*++b = '.';
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b++;
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@ -1072,7 +1003,7 @@ write_dns_nameenc(char *buf, size_t buflen, char *data, int datalen, char downen
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}
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void
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write_dns(int fd, struct query *q, char *data, int datalen, char downenc)
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write_dns(int fd, struct query *q, char *data, size_t datalen, char downenc)
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{
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char buf[64*1024];
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int len = 0;
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@ -1080,11 +1011,9 @@ write_dns(int fd, struct query *q, char *data, int datalen, char downenc)
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if (q->type == T_CNAME || q->type == T_A) {
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char cnamebuf[1024]; /* max 255 */
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write_dns_nameenc(cnamebuf, sizeof(cnamebuf),
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data, datalen, downenc);
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write_dns_nameenc((uint8_t *)cnamebuf, sizeof(cnamebuf), (uint8_t *)data, datalen, downenc);
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len = dns_encode(buf, sizeof(buf), q, QR_ANSWER, cnamebuf,
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sizeof(cnamebuf));
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len = dns_encode(buf, sizeof(buf), q, QR_ANSWER, cnamebuf, sizeof(cnamebuf));
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} else if (q->type == T_MX || q->type == T_SRV) {
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char mxbuf[64*1024];
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char *b = mxbuf;
|
||||
@ -1092,9 +1021,8 @@ write_dns(int fd, struct query *q, char *data, int datalen, char downenc)
|
||||
int res;
|
||||
|
||||
while (1) {
|
||||
res = write_dns_nameenc(b, sizeof(mxbuf) - (b - mxbuf),
|
||||
data + offset,
|
||||
datalen - offset, downenc);
|
||||
res = write_dns_nameenc((uint8_t *)b, sizeof(mxbuf) - (b - mxbuf),
|
||||
(uint8_t *)data + offset, datalen - offset, downenc);
|
||||
if (res < 1) {
|
||||
/* nothing encoded */
|
||||
b++; /* for final \0 */
|
||||
@ -1115,22 +1043,22 @@ write_dns(int fd, struct query *q, char *data, int datalen, char downenc)
|
||||
sizeof(mxbuf));
|
||||
} else if (q->type == T_TXT) {
|
||||
/* TXT with base32 */
|
||||
char txtbuf[64*1024];
|
||||
uint8_t txtbuf[64*1024];
|
||||
size_t space = sizeof(txtbuf) - 1;;
|
||||
|
||||
memset(txtbuf, 0, sizeof(txtbuf));
|
||||
|
||||
if (downenc == 'S') {
|
||||
txtbuf[0] = 's'; /* plain base64(Sixty-four) */
|
||||
len = b64->encode(txtbuf+1, &space, data, datalen);
|
||||
len = b64->encode(txtbuf+1, &space, (uint8_t *)data, datalen);
|
||||
}
|
||||
else if (downenc == 'U') {
|
||||
txtbuf[0] = 'u'; /* Base64 with Underscore */
|
||||
len = b64u->encode(txtbuf+1, &space, data, datalen);
|
||||
len = b64u->encode(txtbuf+1, &space, (uint8_t *)data, datalen);
|
||||
}
|
||||
else if (downenc == 'V') {
|
||||
txtbuf[0] = 'v'; /* Base128 */
|
||||
len = b128->encode(txtbuf+1, &space, data, datalen);
|
||||
len = b128->encode(txtbuf+1, &space, (uint8_t *)data, datalen);
|
||||
}
|
||||
else if (downenc == 'R') {
|
||||
txtbuf[0] = 'r'; /* Raw binary data */
|
||||
@ -1138,9 +1066,9 @@ write_dns(int fd, struct query *q, char *data, int datalen, char downenc)
|
||||
memcpy(txtbuf + 1, data, len);
|
||||
} else {
|
||||
txtbuf[0] = 't'; /* plain base32(Thirty-two) */
|
||||
len = b32->encode(txtbuf+1, &space, data, datalen);
|
||||
len = b32->encode(txtbuf+1, &space, (uint8_t *)data, datalen);
|
||||
}
|
||||
len = dns_encode(buf, sizeof(buf), q, QR_ANSWER, txtbuf, len+1);
|
||||
len = dns_encode(buf, sizeof(buf), q, QR_ANSWER, (char *)txtbuf, len+1);
|
||||
} else {
|
||||
/* Normal NULL-record encode */
|
||||
len = dns_encode(buf, sizeof(buf), q, QR_ANSWER, data, datalen);
|
||||
@ -1152,22 +1080,47 @@ write_dns(int fd, struct query *q, char *data, int datalen, char downenc)
|
||||
}
|
||||
|
||||
if (debug >= 2) {
|
||||
fprintf(stderr, "TX: client %s, type %d, name %s, %d bytes data\n",
|
||||
format_addr(&q->from, q->fromlen), q->type, q->name, datalen);
|
||||
fprintf(stderr, "TX: client %s ID %5d, %lu bytes data, type %d, name '%10s'\n",
|
||||
format_addr(&q->from, q->fromlen), q->id, datalen, q->type, q->name);
|
||||
}
|
||||
|
||||
sendto(fd, buf, len, 0, (struct sockaddr*)&q->from, q->fromlen);
|
||||
}
|
||||
|
||||
void
|
||||
send_data_or_ping_response(int tun_fd, int dns_fd, struct dnsfd *dns_fds, int userid, struct query *q, int ping) {
|
||||
uint8_t unpacked[64*1024];
|
||||
size_t read;
|
||||
|
||||
/* if waiting for an ACK to be sent back upstream (on incoming buffer) */
|
||||
if (users[userid].next_upstream_ack < 0) {
|
||||
users[userid].next_upstream_ack = window_get_next_ack(users[userid].incoming);
|
||||
}
|
||||
window_tick(users[userid].outgoing);
|
||||
|
||||
read = window_reassemble_data(users[userid].incoming, unpacked, sizeof(unpacked), NULL);
|
||||
window_tick(users[userid].incoming);
|
||||
|
||||
if (read > 0) { /* Data reassembled successfully + cleared out of buffer */
|
||||
handle_full_packet(tun_fd, dns_fds, userid, unpacked, read);
|
||||
}
|
||||
|
||||
send_frag_or_dataless(dns_fd, userid, q, ping);
|
||||
|
||||
/* Save new query and time info */
|
||||
memcpy(&(users[userid].q), q, sizeof(struct query));
|
||||
users[userid].last_pkt = time(NULL);
|
||||
}
|
||||
|
||||
void
|
||||
handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query *q, int domain_len)
|
||||
/* Handles a NULL DNS request. See doc/proto_XXXXXXXX.txt for details on iodine protocol. */
|
||||
{
|
||||
struct in_addr tempip;
|
||||
char in[512];
|
||||
uint8_t in[512];
|
||||
char logindata[16];
|
||||
char out[64*1024];
|
||||
static char unpacked[64*1024];
|
||||
uint8_t out[64*1024];
|
||||
static uint8_t unpacked[64*1024];
|
||||
char *tmp[2];
|
||||
int userid;
|
||||
size_t read;
|
||||
@ -1202,45 +1155,47 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
|
||||
userid = find_available_user();
|
||||
if (userid >= 0) {
|
||||
int i;
|
||||
|
||||
users[userid].seed = rand();
|
||||
struct tun_user *u = &users[userid];
|
||||
u->seed = rand();
|
||||
/* Store remote IP number */
|
||||
memcpy(&(users[userid].host), &(q->from), q->fromlen);
|
||||
users[userid].hostlen = q->fromlen;
|
||||
memcpy(&(u->host), &(q->from), q->fromlen);
|
||||
u->hostlen = q->fromlen;
|
||||
|
||||
memcpy(&(users[userid].q), q, sizeof(struct query));
|
||||
users[userid].encoder = get_base32_encoder();
|
||||
users[userid].downenc = 'T';
|
||||
send_version_response(dns_fd, VERSION_ACK, users[userid].seed, userid, q);
|
||||
memcpy(&(u->q), q, sizeof(struct query));
|
||||
u->encoder = get_base32_encoder();
|
||||
u->downenc = 'T';
|
||||
u->downenc_bits = 5;
|
||||
send_version_response(dns_fd, VERSION_ACK, u->seed, userid, q);
|
||||
syslog(LOG_INFO, "accepted version for user #%d from %s",
|
||||
userid, format_addr(&q->from, q->fromlen));
|
||||
users[userid].q.id = 0;
|
||||
users[userid].q.id2 = 0;
|
||||
users[userid].q_sendrealsoon.id = 0;
|
||||
users[userid].q_sendrealsoon.id2 = 0;
|
||||
users[userid].q_sendrealsoon_new = 0;
|
||||
users[userid].fragsize = 100; /* very safe */
|
||||
users[userid].conn = CONN_DNS_NULL;
|
||||
users[userid].lazy = 0;
|
||||
u->q.id = 0;
|
||||
u->q.id2 = 0;
|
||||
u->fragsize = 100; /* very safe */
|
||||
u->conn = CONN_DNS_NULL;
|
||||
u->lazy = 0;
|
||||
// TODO: client specified window size
|
||||
users[userid].incoming = window_buffer_init(128, 10, MAX_FRAGSIZE, WINDOW_RECVING);
|
||||
users[userid].outgoing = window_buffer_init(16, 10, users[userid].fragsize, WINDOW_SENDING);
|
||||
users[userid].next_upstream_ack = -1;
|
||||
u->incoming = window_buffer_init(INFRAGBUF_LEN, 10, MAX_FRAGSIZE, WINDOW_RECVING);
|
||||
u->outgoing = window_buffer_init(OUTFRAGBUF_LEN, 10,
|
||||
u->encoder->get_raw_length(u->fragsize) - DOWNSTREAM_PING_HDR, WINDOW_SENDING);
|
||||
u->next_upstream_ack = -1;
|
||||
#ifdef DNSCACHE_LEN
|
||||
{
|
||||
for (i = 0; i < DNSCACHE_LEN; i++) {
|
||||
users[userid].dnscache_q[i].id = 0;
|
||||
users[userid].dnscache_answerlen[i] = 0;
|
||||
u->dnscache_q[i].id = 0;
|
||||
u->dnscache_answerlen[i] = 0;
|
||||
}
|
||||
}
|
||||
users[userid].dnscache_lastfilled = 0;
|
||||
u->dnscache_lastfilled = 0;
|
||||
#endif
|
||||
for (i = 0; i < QMEMPING_LEN; i++)
|
||||
users[userid].qmemping_type[i] = T_UNSET;
|
||||
users[userid].qmemping_lastfilled = 0;
|
||||
/*for (i = 0; i < QMEMPING_LEN; i++)
|
||||
u->qmemping_type[i] = T_UNSET;
|
||||
u->qmemping_lastfilled = 0;
|
||||
for (i = 0; i < QMEMDATA_LEN; i++)
|
||||
users[userid].qmemdata_type[i] = T_UNSET;
|
||||
users[userid].qmemdata_lastfilled = 0;
|
||||
u->qmemdata_type[i] = T_UNSET;
|
||||
u->qmemdata_lastfilled = 0;*/
|
||||
if (debug >= 1)
|
||||
fprintf(stderr, "User %d connected with correct version from %s.\n",
|
||||
userid, format_addr(&q->from, q->fromlen));
|
||||
} else {
|
||||
/* No space for another user */
|
||||
send_version_response(dns_fd, VERSION_FULL, created_users, 0, q);
|
||||
@ -1262,11 +1217,13 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
|
||||
|
||||
/* Login phase, handle auth */
|
||||
userid = unpacked[0];
|
||||
|
||||
if (debug >= 3)
|
||||
fprintf(stderr, "Received login request for user %d from %s.\n",
|
||||
userid, format_addr(&q->from, q->fromlen));
|
||||
if (check_user_and_ip(userid, q) != 0) {
|
||||
write_dns(dns_fd, q, "BADIP", 5, 'T');
|
||||
syslog(LOG_WARNING, "dropped login request from user #%d from unexpected source %s",
|
||||
userid, format_addr(&q->from, q->fromlen));
|
||||
syslog(LOG_WARNING, "dropped login request from user #%d from %s; expected source %s",
|
||||
userid, format_addr(&q->from, q->fromlen), format_addr(&users[userid].host, users[userid].hostlen));
|
||||
return;
|
||||
} else {
|
||||
users[userid].last_pkt = time(NULL);
|
||||
@ -1282,10 +1239,10 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
|
||||
tempip.s_addr = users[userid].tun_ip;
|
||||
tmp[1] = strdup(inet_ntoa(tempip));
|
||||
|
||||
read = snprintf(out, sizeof(out), "%s-%s-%d-%d",
|
||||
read = snprintf((char *)out, sizeof(out), "%s-%s-%d-%d",
|
||||
tmp[0], tmp[1], my_mtu, netmask);
|
||||
|
||||
write_dns(dns_fd, q, out, read, users[userid].downenc);
|
||||
write_dns(dns_fd, q, (char *)out, read, users[userid].downenc);
|
||||
q->id = 0;
|
||||
syslog(LOG_NOTICE, "accepted password from user #%d, given IP %s", userid, tmp[1]);
|
||||
|
||||
@ -1331,7 +1288,7 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
|
||||
|
||||
/* Reply with received hostname as data */
|
||||
/* No userid here, reply with lowest-grade downenc */
|
||||
write_dns(dns_fd, q, in, domain_len, 'T');
|
||||
write_dns(dns_fd, q, (char *)in, domain_len, 'T');
|
||||
return;
|
||||
} else if(in[0] == 'S' || in[0] == 's') { /* Switch upstream codec */
|
||||
int codec;
|
||||
@ -1389,31 +1346,37 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
|
||||
return; /* illegal id */
|
||||
}
|
||||
|
||||
int bits = 0;
|
||||
switch (in[2]) {
|
||||
case 'T':
|
||||
case 't':
|
||||
users[userid].downenc = 'T';
|
||||
write_dns(dns_fd, q, "Base32", 6, users[userid].downenc);
|
||||
bits = 5;
|
||||
break;
|
||||
case 'S':
|
||||
case 's':
|
||||
users[userid].downenc = 'S';
|
||||
write_dns(dns_fd, q, "Base64", 6, users[userid].downenc);
|
||||
bits = 6;
|
||||
break;
|
||||
case 'U':
|
||||
case 'u':
|
||||
users[userid].downenc = 'U';
|
||||
write_dns(dns_fd, q, "Base64u", 7, users[userid].downenc);
|
||||
bits = 6;
|
||||
break;
|
||||
case 'V':
|
||||
case 'v':
|
||||
users[userid].downenc = 'V';
|
||||
write_dns(dns_fd, q, "Base128", 7, users[userid].downenc);
|
||||
bits = 7;
|
||||
break;
|
||||
case 'R':
|
||||
case 'r':
|
||||
users[userid].downenc = 'R';
|
||||
write_dns(dns_fd, q, "Raw", 3, users[userid].downenc);
|
||||
bits = 8;
|
||||
break;
|
||||
case 'L':
|
||||
case 'l':
|
||||
@ -1429,6 +1392,14 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
|
||||
write_dns(dns_fd, q, "BADCODEC", 8, users[userid].downenc);
|
||||
break;
|
||||
}
|
||||
if (bits) {
|
||||
int f = users[userid].fragsize;
|
||||
users[userid].outgoing->maxfraglen = (bits * f) / 8 - DOWNSTREAM_PING_HDR;
|
||||
if (debug >= 1)
|
||||
warnx("Setting max downstream data length to %u bytes for user %d; bits %d (%c)",
|
||||
users[userid].outgoing->maxfraglen, userid, bits, users[userid].downenc);
|
||||
users[userid].downenc_bits = bits;
|
||||
}
|
||||
return;
|
||||
} else if(in[0] == 'Y' || in[0] == 'y') { /* Downstream codec check */
|
||||
int i;
|
||||
@ -1561,12 +1532,17 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
|
||||
write_dns(dns_fd, q, "BADFRAG", 7, users[userid].downenc);
|
||||
} else {
|
||||
users[userid].fragsize = max_frag_size;
|
||||
write_dns(dns_fd, q, &unpacked[1], 2, users[userid].downenc);
|
||||
users[userid].outgoing->maxfraglen = (users[userid].downenc_bits * max_frag_size) /
|
||||
8 - DOWNSTREAM_PING_HDR;
|
||||
write_dns(dns_fd, q, (char *) unpacked + 1, 2, users[userid].downenc);
|
||||
|
||||
if (debug >= 1)
|
||||
warnx("Setting max downstream data length to %u bytes for user %d; bits %d (%c)",
|
||||
users[userid].outgoing->maxfraglen, userid, users[userid].downenc_bits, users[userid].downenc);
|
||||
}
|
||||
return;
|
||||
} else if(in[0] == 'P' || in[0] == 'p') { /* Ping request */
|
||||
int dn_seq, up_seq, dn_wins, up_wins;
|
||||
int didsend = 0;
|
||||
int dn_seq, up_seq, dn_wins, up_wins, dn_ack;
|
||||
int respond;
|
||||
|
||||
/* We can't handle id=0, that's "no packet" to us. So drop
|
||||
@ -1579,8 +1555,10 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
|
||||
return;
|
||||
|
||||
read = unpack_data(unpacked, sizeof(unpacked), in + 1, domain_len - 1, b32);
|
||||
if (read < 7)
|
||||
if (read < UPSTREAM_PING) {
|
||||
if (debug >= 1) warnx("Invalid ping! Length %lu", read);
|
||||
return;
|
||||
}
|
||||
|
||||
/* Ping packet, store userid */
|
||||
userid = unpacked[0];
|
||||
@ -1594,100 +1572,35 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
|
||||
if (answer_from_dnscache(dns_fd, userid, q))
|
||||
return;
|
||||
#endif
|
||||
|
||||
/* Check if duplicate (and not in full dnscache any more) */
|
||||
/* TODO: incoming query handling for lazy mode */
|
||||
/* Check if duplicate (and not in full dnscache any more) * /
|
||||
if (answer_from_qmem(dns_fd, q, users[userid].qmemping_cmc,
|
||||
users[userid].qmemping_type, QMEMPING_LEN,
|
||||
(void *) unpacked))
|
||||
return;
|
||||
return; */
|
||||
|
||||
/* Check if duplicate of waiting queries; impatient DNS relays
|
||||
like to re-try early and often (with _different_ .id!) */
|
||||
if (users[userid].q.id != 0 &&
|
||||
q->type == users[userid].q.type &&
|
||||
!strcmp(q->name, users[userid].q.name) &&
|
||||
users[userid].lazy) {
|
||||
/* We have this ping already, and it's waiting to be
|
||||
answered. Always keep the last duplicate, since the
|
||||
relay may have forgotten its first version already.
|
||||
Our answer will go to both.
|
||||
(If we already sent an answer, qmem/cache will
|
||||
have triggered.) */
|
||||
if (debug >= 2) {
|
||||
fprintf(stderr, "PING pkt from user %d = dupe from impatient DNS server, remembering\n",
|
||||
userid);
|
||||
}
|
||||
users[userid].q.id2 = q->id;
|
||||
users[userid].q.fromlen2 = q->fromlen;
|
||||
memcpy(&(users[userid].q.from2), &(q->from), q->fromlen);
|
||||
return;
|
||||
dn_ack = ((unpacked[6] >> 2) & 1) ? unpacked[1] : -1;
|
||||
up_wins = unpacked[2];
|
||||
dn_wins = unpacked[3];
|
||||
dn_seq = unpacked[4];
|
||||
up_seq = unpacked[5];
|
||||
respond = unpacked[6] & 1;
|
||||
|
||||
/* TODO: Use ping to re-sync window buffer */
|
||||
if (debug >= 2) {
|
||||
fprintf(stderr, "PING pkt from user %d, down %d/%d, up %d/%d, ACK %d\n", userid, dn_seq, dn_wins, up_seq, up_wins, dn_ack);
|
||||
}
|
||||
|
||||
if (users[userid].q_sendrealsoon.id != 0 &&
|
||||
q->type == users[userid].q_sendrealsoon.type &&
|
||||
!strcmp(q->name, users[userid].q_sendrealsoon.name)) {
|
||||
/* Outer select loop will send answer immediately,
|
||||
to both queries. */
|
||||
if (debug >= 2) {
|
||||
fprintf(stderr, "PING pkt from user %d = dupe from impatient DNS server, remembering\n",
|
||||
userid);
|
||||
}
|
||||
users[userid].q_sendrealsoon.id2 = q->id;
|
||||
users[userid].q_sendrealsoon.fromlen2 = q->fromlen;
|
||||
memcpy(&(users[userid].q_sendrealsoon.from2),
|
||||
&(q->from), q->fromlen);
|
||||
return;
|
||||
}
|
||||
window_ack(users[userid].outgoing, dn_ack);
|
||||
|
||||
dn_seq = unpacked[1];
|
||||
up_seq = unpacked[2];
|
||||
up_wins = unpacked[3];
|
||||
dn_wins = unpacked[4];
|
||||
respond = unpacked[5] & 1;
|
||||
|
||||
if (debug >= 1) {
|
||||
fprintf(stderr, "PING pkt from user %d, down %d/%d, up %d/%d\n", userid, dn_seq, dn_wins, up_seq, up_wins);
|
||||
}
|
||||
|
||||
/* If there is a query that must be returned real soon, do it.
|
||||
May contain new downstream data if the ping had a new ack. TODO: ping with downstream data
|
||||
Otherwise, may also be re-sending old data. */
|
||||
if (users[userid].q_sendrealsoon.id != 0) {
|
||||
if (respond) send_ping_response(dns_fd, userid, &users[userid].q_sendrealsoon);
|
||||
else send_frag_or_dataless(dns_fd, userid, &users[userid].q_sendrealsoon);
|
||||
}
|
||||
|
||||
/* We need to store a new query, so if there still is an
|
||||
earlier query waiting, always send a reply to finish it.
|
||||
May contain new downstream data if the ping had a new ack.
|
||||
Otherwise, may also be re-sending old data.
|
||||
(This is duplicate data if we had q_sendrealsoon above.) */
|
||||
if (users[userid].q.id != 0) {
|
||||
didsend = 1;
|
||||
if (respond)
|
||||
send_ping_response(dns_fd, userid, &users[userid].q);
|
||||
else
|
||||
if (send_frag_or_dataless(dns_fd, userid, &users[userid].q) == 1)
|
||||
/* new packet from queue, send immediately */
|
||||
didsend = 0;
|
||||
}
|
||||
|
||||
/* Save new query and time info */
|
||||
memcpy(&(users[userid].q), q, sizeof(struct query));
|
||||
users[userid].last_pkt = time(NULL);
|
||||
|
||||
/* If anything waiting and we didn't already send above, send
|
||||
it now. And always send immediately if we're not lazy
|
||||
(then above won't have sent at all). TODO only call send_frag if sending */
|
||||
if ((!didsend) || !users[userid].lazy)
|
||||
send_frag_or_dataless(dns_fd, userid, &users[userid].q);
|
||||
send_data_or_ping_response(tun_fd, dns_fd, dns_fds, userid, q, respond);
|
||||
|
||||
} else if((in[0] >= '0' && in[0] <= '9') /* Upstream data packet */
|
||||
|| (in[0] >= 'a' && in[0] <= 'f')
|
||||
|| (in[0] >= 'A' && in[0] <= 'F')) {
|
||||
int didsend = 0;
|
||||
int code = -1;
|
||||
static fragment f;
|
||||
size_t len;
|
||||
|
||||
/* Need 6 char header + >=1 char data */
|
||||
if (domain_len < 7)
|
||||
@ -1699,8 +1612,10 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
|
||||
different id, then all okay.
|
||||
Else client doesn't get our ack, and will retransmit in
|
||||
1 second. */
|
||||
if (q->id == 0)
|
||||
if (q->id == 0) {
|
||||
warnx("Query with ID 0!");
|
||||
return;
|
||||
}
|
||||
|
||||
if ((in[0] >= '0' && in[0] <= '9'))
|
||||
code = in[0] - '0';
|
||||
@ -1721,142 +1636,41 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
|
||||
if (answer_from_dnscache(dns_fd, userid, q))
|
||||
return;
|
||||
#endif
|
||||
/* TODO: incoming query buffer/handling for lazy mode */
|
||||
|
||||
/* Check if duplicate (and not in full dnscache any more) */
|
||||
if (answer_from_qmem_data(dns_fd, userid, q))
|
||||
return;
|
||||
|
||||
/* Check if duplicate of waiting queries; impatient DNS relays
|
||||
like to re-try early and often (with _different_ .id!) */
|
||||
if (users[userid].q.id != 0 &&
|
||||
q->type == users[userid].q.type &&
|
||||
!strcmp(q->name, users[userid].q.name) &&
|
||||
users[userid].lazy) {
|
||||
/* We have this packet already, and it's waiting to be
|
||||
answered. Always keep the last duplicate, since the
|
||||
relay may have forgotten its first version already.
|
||||
Our answer will go to both.
|
||||
(If we already sent an answer, qmem/cache will
|
||||
have triggered.) */
|
||||
if (debug >= 2) {
|
||||
fprintf(stderr, "IN pkt from user %d = dupe from impatient DNS server, remembering\n", userid);
|
||||
}
|
||||
users[userid].q.id2 = q->id;
|
||||
users[userid].q.fromlen2 = q->fromlen;
|
||||
memcpy(&(users[userid].q.from2), &(q->from), q->fromlen);
|
||||
return;
|
||||
}
|
||||
|
||||
if (users[userid].q_sendrealsoon.id != 0 &&
|
||||
q->type == users[userid].q_sendrealsoon.type &&
|
||||
!strcmp(q->name, users[userid].q_sendrealsoon.name)) {
|
||||
/* Outer select loop will send answer immediately to both queries. */
|
||||
if (debug >= 2) {
|
||||
fprintf(stderr, "IN pkt from user %d = dupe from impatient DNS server, remembering\n", userid);
|
||||
}
|
||||
users[userid].q_sendrealsoon.id2 = q->id;
|
||||
users[userid].q_sendrealsoon.fromlen2 = q->fromlen;
|
||||
memcpy(&(users[userid].q_sendrealsoon.from2), &(q->from), q->fromlen);
|
||||
return;
|
||||
}
|
||||
|
||||
/* TODO: Check if duplicate of waiting queries (ping and data) */
|
||||
|
||||
/* Decode upstream data header - see docs/proto_XXXXXXXX.txt */
|
||||
/* First byte (after userid) = CMC (ignored?) */
|
||||
f.seqID = (b32_8to5(in[2]) << 2) | (b32_8to5(in[3]) >> 2);
|
||||
f.ack_other = (b32_8to5(in[5]) & 8) ? ((b32_8to5(in[3]) & 3) << 6)
|
||||
| (b32_8to5(in[4]) << 1) | (b32_8to5(in[5]) & 1) : -1;
|
||||
f.is_nack = (b32_8to5(in[5]) >> 2) & 1;
|
||||
f.start = (b32_8to5(in[5]) >> 1) & 1;
|
||||
f.end = b32_8to5(in[5]) & 1;
|
||||
/* First byte (after userid) = CMC (ignored) */
|
||||
// f.seqID = (b32_8to5(in[2]) << 2) | (b32_8to5(in[3]) >> 2);
|
||||
// f.ack_other = (b32_8to5(in[5]) & 8) ? ((b32_8to5(in[3]) & 3) << 6)
|
||||
// | (b32_8to5(in[4]) << 1) | ((b32_8to5(in[5]) >> 4) & 1) : -1;
|
||||
// f.is_nack = (b32_8to5(in[5]) >> 2) & 1;
|
||||
// f.start = (b32_8to5(in[5]) >> 1) & 1;
|
||||
// f.end = b32_8to5(in[5]) & 1;
|
||||
len = sizeof(unpacked);
|
||||
read = b32->decode(unpacked, &len, in + 2, 5);
|
||||
f.seqID = unpacked[0];
|
||||
unpacked[2] >>= 4; /* Lower 4 bits are unused */
|
||||
f.ack_other = ((unpacked[2] >> 3) & 1) ? unpacked[1] : -1;
|
||||
f.is_nack = (unpacked[2] >> 2) & 1;
|
||||
f.start = (unpacked[2] >> 1) & 1;
|
||||
f.end = unpacked[2] & 1;
|
||||
|
||||
/* Decode remainder of data with user encoding */
|
||||
read = unpack_data(unpacked, sizeof(unpacked), in + UPSTREAM_HDR,
|
||||
domain_len - UPSTREAM_HDR, users[userid].encoder);
|
||||
if (debug >= 4) warnx("++++ UNPACKED %d bytes into %lu using %s with header len %d",
|
||||
domain_len, read, users[userid].encoder->name, UPSTREAM_HDR);
|
||||
|
||||
f.len = MIN(read, MAX_FRAGSIZE);
|
||||
memcpy(f.data, unpacked, read);
|
||||
memcpy(f.data, unpacked, f.len);
|
||||
|
||||
window_process_incoming_fragment(users[userid].incoming, &f);
|
||||
|
||||
window_ack(users[userid].outgoing, f.ack_other);
|
||||
|
||||
/* if waiting for an ACK to be sent back upstream (on incoming buffer) */
|
||||
if (users[userid].next_upstream_ack < 0) {
|
||||
users[userid].next_upstream_ack = window_get_next_ack(users[userid].incoming);
|
||||
}
|
||||
|
||||
read = window_reassemble_data(users[userid].incoming, (uint8_t *)unpacked, sizeof(unpacked), NULL);
|
||||
|
||||
if (read > 0) { /* Data reassembled successfully + cleared out of buffer */
|
||||
handle_full_packet(tun_fd, dns_fds, userid, (uint8_t *)unpacked, read);
|
||||
}
|
||||
|
||||
window_tick(users[userid].incoming);
|
||||
|
||||
/* If there is a query that must be returned real soon, do it.
|
||||
Includes an ack of the just received upstream fragment,
|
||||
may contain new data. */
|
||||
if (users[userid].q_sendrealsoon.id != 0) {
|
||||
didsend = 1;
|
||||
if (send_frag_or_dataless(dns_fd, userid, &users[userid].q_sendrealsoon) == 1)
|
||||
/* new packet from queue, send immediately */
|
||||
didsend = 0;
|
||||
}
|
||||
|
||||
/* If we already have an earlier query waiting, we need to
|
||||
get rid of it to store the new query.
|
||||
- If we have new data waiting and not yet sent above, send immediately.
|
||||
- If this wasn't the last upstream fragment, then we expect
|
||||
more, so ack immediately if we didn't already.
|
||||
- If we are in non-lazy mode, there should be no query
|
||||
waiting, but if there is, send immediately.
|
||||
- In all other cases (mostly the last-fragment cases),
|
||||
we can afford to wait just a tiny little while for the
|
||||
TCP ack to arrive from our tun. Note that this works best
|
||||
when there is only one client.
|
||||
*/
|
||||
// if (users[userid].q.id != 0) {
|
||||
// if ((users[userid].outpacket.len > 0 && !didsend) ||
|
||||
// (upstream_ok && !lastfrag && !didsend) ||
|
||||
// (!upstream_ok && !didsend) ||
|
||||
// !users[userid].lazy) {
|
||||
// didsend = 1;
|
||||
// if (send_frag_or_dataless(dns_fd, userid, &users[userid].q) == 1)
|
||||
// /* new packet from queue, send immediately */
|
||||
// didsend = 0;
|
||||
// } else {
|
||||
// memcpy(&(users[userid].q_sendrealsoon), &(users[userid].q),
|
||||
// sizeof(struct query));
|
||||
// users[userid].q_sendrealsoon_new = 1;
|
||||
// users[userid].q.id = 0; /* used */
|
||||
// didsend = 1;
|
||||
// }
|
||||
// }
|
||||
|
||||
/* Save new query and time info */
|
||||
memcpy(&(users[userid].q), q, sizeof(struct query));
|
||||
users[userid].last_pkt = time(NULL);
|
||||
|
||||
/* If we still need to ack this upstream frag, do it to keep
|
||||
upstream flowing.
|
||||
- If we have new data waiting and not yet sent above,
|
||||
send immediately.
|
||||
- If this wasn't the last upstream fragment, then we expect
|
||||
more, so ack immediately if we didn't already or are
|
||||
in non-lazy mode.
|
||||
- If this was the last fragment, and we didn't ack already
|
||||
or are in non-lazy mode, send the ack after just a tiny
|
||||
little while so that the TCP ack may have arrived from
|
||||
our tun device.
|
||||
- In all other cases, don't send anything now. */
|
||||
if (!didsend) // TODO: also check if sending
|
||||
send_frag_or_dataless(dns_fd, userid, &users[userid].q);
|
||||
else if (!didsend || !users[userid].lazy) {
|
||||
memcpy(&(users[userid].q_sendrealsoon), &(users[userid].q), sizeof(struct query));
|
||||
users[userid].q_sendrealsoon_new = 1;
|
||||
users[userid].q.id = 0; /* used */
|
||||
}
|
||||
send_data_or_ping_response(tun_fd, dns_fd, dns_fds, userid, q, 0);
|
||||
}
|
||||
}
|
||||
|
||||
@ -1882,8 +1696,8 @@ handle_ns_request(int dns_fd, struct query *q)
|
||||
}
|
||||
|
||||
if (debug >= 2) {
|
||||
fprintf(stderr, "TX: client %s, type %d, name %s, %d bytes NS reply\n",
|
||||
format_addr(&q->from, q->fromlen), q->type, q->name, len);
|
||||
fprintf(stderr, "TX: client %s ID %5d, type %d, name %s, %d bytes NS reply\n",
|
||||
format_addr(&q->from, q->fromlen), q->id, q->type, q->name, len);
|
||||
}
|
||||
if (sendto(dns_fd, buf, len, 0, (struct sockaddr*)&q->from, q->fromlen) <= 0) {
|
||||
warn("ns reply send error");
|
||||
@ -1916,8 +1730,8 @@ handle_a_request(int dns_fd, struct query *q, int fakeip)
|
||||
}
|
||||
|
||||
if (debug >= 2) {
|
||||
fprintf(stderr, "TX: client %s, type %d, name %s, %d bytes A reply\n",
|
||||
format_addr(&q->from, q->fromlen), q->type, q->name, len);
|
||||
fprintf(stderr, "TX: client %s ID %5d, type %d, name %s, %d bytes A reply\n",
|
||||
format_addr(&q->from, q->fromlen), q->id, q->type, q->name, len);
|
||||
}
|
||||
if (sendto(dns_fd, buf, len, 0, (struct sockaddr*)&q->from, q->fromlen) <= 0) {
|
||||
warn("a reply send error");
|
||||
|
||||
11
src/server.h
11
src/server.h
@ -47,6 +47,15 @@
|
||||
#define QMEMDATA_LEN 15
|
||||
/* Max advisable: 36/2 = 18. Total mem usage: QMEMDATA_LEN * USERS * 6 bytes */
|
||||
|
||||
/* Number of fragments in outgoing buffer.
|
||||
* Mem usage: USERS * (MAX_FRAGLEN * OUTFRAGBUF_LEN + sizeof(struct window_buffer) */
|
||||
#define OUTFRAGBUF_LEN 64
|
||||
|
||||
/* Number of fragments in incoming buffer
|
||||
* Minimum recommended = ((max packet size or MTU) / (max up fragsize)) * 2
|
||||
* ie. (1200 / 100) * 2 = 24 */
|
||||
#define INFRAGBUF_LEN 32
|
||||
|
||||
#define PASSWORD_ENV_VAR "IODINED_PASS"
|
||||
|
||||
#if defined IP_RECVDSTADDR
|
||||
@ -102,7 +111,7 @@ void server_stop();
|
||||
int server_tunnel(int tun_fd, struct dnsfd *dns_fds, int bind_fd, int max_idle_time);
|
||||
|
||||
int read_dns(int fd, struct dnsfd *dns_fds, int tun_fd, struct query *q);
|
||||
void write_dns(int fd, struct query *q, char *data, int datalen, char downenc);
|
||||
void write_dns(int fd, struct query *q, char *data, size_t datalen, char downenc);
|
||||
void handle_full_packet(int tun_fd, struct dnsfd *dns_fds, int userid, uint8_t *data, size_t len);
|
||||
void handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query *q, int domain_len);
|
||||
void handle_ns_request(int dns_fd, struct query *q);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user