From d2b019a6df56a6204e226ac85ed91e135539d593 Mon Sep 17 00:00:00 2001 From: Erik Ekman Date: Mon, 5 Jan 2009 17:08:34 +0000 Subject: [PATCH] #7, handle special case, remove up to 1 second pause when doing bulk download --- src/iodine.c | 50 +++++++++++++++++++++++++++++++++++++------------- 1 file changed, 37 insertions(+), 13 deletions(-) diff --git a/src/iodine.c b/src/iodine.c index b6ed9a6..aeda88c 100644 --- a/src/iodine.c +++ b/src/iodine.c @@ -61,6 +61,8 @@ static char *topdomain; static uint16_t rand_seed; static int downstream_seqno; static int downstream_fragment; +static int down_ack_seqno; +static int down_ack_fragment; /* Current IP packet */ static struct packet outpkt; @@ -175,22 +177,36 @@ read_dns(int fd, char *buf, int buflen) rv = dns_decode(buf, buflen, &q, QR_ANSWER, data, r); /* decode the data header, update seqno and frag before next request */ - if (rv > 2) { + if (rv >= 2) { downstream_seqno = (buf[1] >> 5) & 7; downstream_fragment = (buf[1] >> 1) & 15; } - if (is_sending() && chunkid == q.id) { - /* Got ACK on sent packet */ - outpkt.offset += outpkt.sentlen; - if (outpkt.offset == outpkt.len) { - /* Packet completed */ - outpkt.offset = 0; - outpkt.len = 0; - outpkt.sentlen = 0; - } else { - /* More to send */ - send_chunk(fd); + + if (is_sending()) { + if (chunkid == q.id) { + /* Got ACK on sent packet */ + outpkt.offset += outpkt.sentlen; + if (outpkt.offset == outpkt.len) { + /* Packet completed */ + outpkt.offset = 0; + outpkt.len = 0; + outpkt.sentlen = 0; + + /* If the ack contains unacked frag number but no data, + * send a ping to ack the frag number and get more data*/ + if (rv == 2 && ( + downstream_seqno != down_ack_seqno || + downstream_fragment != down_ack_fragment + )) { + + send_ping(fd); + } + } else { + /* More to send */ + send_chunk(fd); + } + } } return rv; @@ -340,7 +356,10 @@ send_chunk(int fd) buf[2] = b32_5to8(code); /* Third byte is 2 bits lower fragment count, 3 bits downstream packet seqno */ code = ((downstream_fragment & 15) << 1) | (outpkt.sentlen == avail); - buf[3] = b32_5to8(code); /* Fourth byte is 4 bits downstream fragment count, 1 bit compression flag */ + buf[3] = b32_5to8(code); /* Fourth byte is 4 bits downstream fragment count, 1 bit last frag flag */ + + down_ack_seqno = downstream_seqno; + down_ack_fragment = downstream_fragment; outpkt.fragment++; send_query(fd, buf); @@ -379,6 +398,9 @@ send_ping(int fd) data[2] = (rand_seed >> 8) & 0xff; data[3] = (rand_seed >> 0) & 0xff; + down_ack_seqno = downstream_seqno; + down_ack_fragment = downstream_fragment; + rand_seed++; send_packet(fd, 'P', data, sizeof(data)); @@ -867,6 +889,8 @@ main(int argc, char **argv) downstream_seqno = 0; downstream_fragment = 0; + down_ack_seqno = 0; + down_ack_fragment = 0; tunnel(tun_fd, dns_fd);