/**
* Calculates and returns the loss event rate
* TODO: add history discounting
*/
double loss_event_rate(struct group_list_t *group)
{
double weights[8] = { 1.0, 1.0, 1.0, 1.0, 0.8, 0.6, 0.4, 0.2 };
double loss_sum_cur, loss_sum_no_cur, weight_sum;
int i;
if (group->slowstart) {
return 0.0;
}
loss_sum_cur = 0;
loss_sum_no_cur = 0;
weight_sum = 0;
for (i = 0; i < 8; i++) {
glog5(group, "loss_events[%d].len=%d", i, group->loss_events[i].len);
if (group->loss_events[i].len != 0) {
loss_sum_cur += group->loss_events[i].len * weights[i];
weight_sum += weights[i];
}
}
for (i = 1; i < 9; i++) {
if (group->loss_events[i].len == 0) break;
loss_sum_no_cur += group->loss_events[i].len * weights[i - 1];
}
glog5(group, "cur_sum=%f, cur_no_sum=%f, weight_sum=%f",
loss_sum_cur, loss_sum_no_cur, weight_sum);
// Return inverse of larger average
if (loss_sum_no_cur > loss_sum_cur) {
return weight_sum / loss_sum_no_cur;
} else {
return weight_sum / loss_sum_cur;
}
}
/**
* Returns the current congestion control rate in bytes / second.
* As specified in RFC 4654
*/
unsigned current_cc_rate(struct group_list_t *group)
{
double p, rtt;
int i, bytes, thresh;
if (group->rtt != 0.0) {
rtt = group->rtt;
} else {
rtt = group->grtt;
}
p = loss_event_rate(group);
if (p == 0.0) {
thresh = (int)(group->grtt * 1000000 * 4);
bytes = 0;
i = group->max_txseq;
while ((i != group->start_txseq) &&
(diff_usec(group->loss_history[group->max_txseq].t,
group->loss_history[i].t) < thresh)) {
bytes += group->loss_history[i--].size;
}
return (unsigned)(2.0 * bytes / (4.0 * group->grtt));
} else {
glog5(group, "getting cc rate, p=%f, rtt=%f", p, rtt);
return (unsigned)(group->datapacketsize /
(rtt * (sqrt(p * 2.0 / 3.0) +
(12 * sqrt(p * 3.0 / 8.0) * p * (1 + (32 * p * p))))));
}
}
/**
* Sets the timeout time for a given group list member
*/
void set_timeout(struct pr_group_list_t *group, int pending_reset, int rescale)
{
int pending, i;
if (group->phase == PR_PHASE_READY) {
if (!rescale) {
gettimeofday(&group->start_phase_timeout_time, NULL);
}
group->phase_timeout_time = group->start_phase_timeout_time;
add_timeval_d(&group->phase_timeout_time, 2 * group->grtt);
}
glog5(group, "set timeout: pending_reset=%d", pending_reset);
for (pending = 0, i = 0; (i < MAX_PEND) && !pending; i++) {
if (group->pending[i].msg != 0) {
glog5(group, "set timeout: found pending %s",
func_name(group->pending[i].msg));
pending = group->pending[i].msg;
}
}
if (pending) {
if (pending_reset) {
if (!rescale) {
gettimeofday(&group->start_timeout_time, NULL);
}
group->timeout_time = group->start_timeout_time;
add_timeval_d(&group->timeout_time, 1 * group->grtt);
}
} else {
if (!rescale) {
gettimeofday(&group->start_timeout_time, NULL);
}
group->timeout_time = group->start_timeout_time;
if (group->robust * group->grtt < 1.0) {
add_timeval_d(&group->timeout_time, 1.0);
} else {
add_timeval_d(&group->timeout_time, group->robust * group->grtt);
}
}
}
/**
* Gets the current timeout value to use for the main loop
*
* First check to see if any active groups have an expired timeout, and
* handle that timeout. Once all expired timeouts have been handled, find
* the active group with the earliest timeout and return the time until that
* timeout. If there are no active groups, return NULL.
*/
struct timeval *getrecenttimeout(void)
{
static struct timeval tv = {0,0};
struct timeval current_timestamp, min_timestamp;
int i, found_timeout, done, sent_naks;
struct group_list_t *group;
unsigned int section, nak_count;
unsigned char *naks;
gettimeofday(¤t_timestamp, NULL);
done = 0;
while (!done) {
found_timeout = 0;
done = 1;
for (i = 0; i < MAXLIST; i++) {
group = &group_list[i];
if (group->group_id != 0) {
if (cmptimestamp(current_timestamp, group->timeout_time) >= 0) {
switch (group->phase) {
case PHASE_REGISTERED:
send_register(group);
break;
case PHASE_RECEIVING:
case PHASE_MIDGROUP:
glog1(group, "Transfer timed out");
send_abort(group, "Transfer timed out");
break;
case PHASE_COMPLETE:
send_complete(group, 0);
break;
}
done = 0;
} else if ((!found_timeout) ||
(cmptimestamp(group->timeout_time,
min_timestamp) < 0)) {
glog5(group, "found min timeout time: %d:%06d",
group->timeout_time.tv_sec,
group->timeout_time.tv_usec);
min_timestamp = group->timeout_time;
found_timeout = 1;
}
// Check for a NAK timeout for sending a STATUS or COMPLETE
if ((group->fileinfo.nak_time.tv_sec != 0) &&
cmptimestamp(current_timestamp,
group->fileinfo.nak_time) >= 0) {
group->fileinfo.nak_time.tv_sec = 0;
group->fileinfo.nak_time.tv_usec = 0;
// Send NAKs
sent_naks = 0;
retry_naks:
for (section = group->fileinfo.nak_section_first;
section < group->fileinfo.nak_section_last;
section++) {
naks = NULL;
nak_count = get_naks(group, section, &naks);
glog3(group, "read %d NAKs for section %d",
nak_count, section);
if (nak_count > 0) {
send_status(group, section, naks, nak_count);
sent_naks = 1;
}
free(naks);
naks = NULL;
}
if (file_done(group, 1)) {
glog2(group, "File transfer complete");
send_complete(group, 0);
file_cleanup(group, 0);
} else if (group->fileinfo.got_done && !sent_naks) {
// We didn't send any NAKs since the last time
// but the server is asking for some,
// so check all prior sections
group->fileinfo.nak_section_last =
group->fileinfo.nak_section_first;
group->fileinfo.nak_section_first = 0;
group->fileinfo.got_done = 0;
goto retry_naks;
}
} else if ((group->fileinfo.nak_time.tv_sec != 0) &&
((!found_timeout) ||
(cmptimestamp(group->fileinfo.nak_time,
min_timestamp) < 0))) {
glog5(group, "found min nak time: %d:%06d",
group->fileinfo.nak_time.tv_sec,
group->fileinfo.nak_time.tv_usec);
min_timestamp = group->fileinfo.nak_time;
found_timeout = 1;
}
// Check congestion control feedback timer
if (!group->isclr) {
if ((group->cc_time.tv_sec != 0) &&
(cmptimestamp(current_timestamp,
group->cc_time) >= 0)) {
send_cc_ack(group);
} else if ((group->cc_time.tv_sec != 0) &&
((!found_timeout) ||
(cmptimestamp(group->cc_time,
min_timestamp) < 0))) {
glog5(group, "found min CC time: %d:%06d",
group->cc_time.tv_sec, group->cc_time.tv_usec);
min_timestamp = group->cc_time;
found_timeout = 1;
}
}
}
}
// Check timeout for proxy key request
if (has_proxy && (proxy_pubkey.key == 0)) {
if (cmptimestamp(current_timestamp, next_keyreq_time) >= 0) {
send_key_req();
done = 0;
} else if ((!found_timeout) ||
(cmptimestamp(next_keyreq_time, min_timestamp) < 0)) {
min_timestamp = next_keyreq_time;
found_timeout = 1;
}
}
// Check timeout for sending heartbeat
if (hbhost_count) {
if (cmptimestamp(current_timestamp, next_hb_time) >= 0) {
send_hb_request(listener, hb_hosts, hbhost_count,
&next_hb_time, hb_interval, uid);
done = 0;
} else if ((!found_timeout) ||
(cmptimestamp(next_hb_time, min_timestamp) < 0)) {
min_timestamp = next_hb_time;
found_timeout = 1;
}
}
}
if (found_timeout) {
tv = diff_timeval(min_timestamp, current_timestamp);
return &tv;
} else {
return NULL;
}
}
/**
* This is the main message reading loop. Messages are read, validated,
* decrypted if necessary, then passed to the appropriate routine for handling.
*/
void mainloop(void)
{
struct uftp_h *header;
struct group_list_t *group;
unsigned char *buf, *decrypted, *message;
char rxname[INET6_ADDRSTRLEN];
unsigned int decryptlen, meslen;
int packetlen, rval, i, ecn;
uint8_t version, *func, tos;
uint16_t txseq;
union sockaddr_u src;
struct timeval *tv, rxtime;
double new_grtt;
log2(0, 0, 0, "%s", VERSIONSTR);
for (i = 0; i < key_count; i++) {
if (privkey_type[i] == KEYBLOB_RSA) {
log2(0, 0, 0, "Loaded %d bit RSA key with fingerprint %s",
RSA_keylen(privkey[i].rsa) * 8,
print_key_fingerprint(privkey[i], KEYBLOB_RSA));
} else {
log2(0, 0, 0, "Loaded ECDSA key with curve %s and fingerprint %s",
curve_name(get_EC_curve(privkey[i].ec)),
print_key_fingerprint(privkey[i], KEYBLOB_EC));
}
}
buf = safe_calloc(MAXMTU, 1);
decrypted = safe_calloc(MAXMTU, 1);
header = (struct uftp_h *)buf;
while (1) {
tv = getrecenttimeout();
if (tv) {
log5(0, 0, 0, "read timeout: %d.%06d", tv->tv_sec, tv->tv_usec);
}
if (read_packet(listener, &src, buf, &packetlen,
MAXMTU, tv, &tos) <= 0) {
continue;
}
gettimeofday(&rxtime, NULL);
if ((rval = getnameinfo((struct sockaddr *)&src, family_len(src),
rxname, sizeof(rxname), NULL, 0, NI_NUMERICHOST)) != 0) {
log1(0, 0, 0, "getnameinfo failed: %s", gai_strerror(rval));
}
if (header->version == UFTP_VER_NUM) {
version = header->version;
group = find_group(ntohl(header->group_id), header->group_inst);
} else {
log1(0, 0, 0, "Invalid message from %s: not uftp packet "
"or invalid version", rxname);
continue;
}
if (packetlen < sizeof(struct uftp_h) + 4) {
log1(0, 0, 0, "Invalid packet size from %s: %d", rxname, packetlen);
continue;
}
txseq = htons(header->seq);
// A KEY_INFO or ABORT could come from a proxy, so don't check the seq
// TODO: need to account for these in the loss history
if ((group != NULL) && (header->func != KEYINFO) &&
(header->func != ABORT)) {
if ((int16_t)(group->max_txseq - txseq) > MAXMISORDER) {
glog3(group, "seq out of range, dropping");
continue;
}
if (group->cc_type != CC_NONE) {
ecn = ((tos & 0x3) == 3);
update_loss_history(group, txseq, packetlen, ecn);
} else if ((int16_t)(txseq - group->max_txseq) > 0) {
group->max_txseq = txseq;
}
}
if ((header->func == ENCRYPTED) && (group != NULL) &&
(group->keytype != KEY_NONE)) {
if (group->phase == PHASE_REGISTERED) {
glog1(group, "Got encrypted packet from %s "
"but keys not established", rxname);
}
if (!validate_and_decrypt(buf, packetlen, &decrypted, &decryptlen,
group->keytype, group->groupkey, group->groupsalt,
group->ivlen, group->hashtype, group->grouphmackey,
group->hmaclen, group->sigtype, group->keyextype,
group->server_pubkey, group->server_pubkeylen)) {
glog1(group, "Rejecting message from %s: "
"decrypt/validate failed", rxname);
continue;
}
func = (uint8_t *)decrypted;
message = decrypted;
meslen = decryptlen;
} else {
if ((group != NULL) && (group->keytype != KEY_NONE) &&
((header->func == FILEINFO) || (header->func == FILESEG) ||
(header->func == DONE) || (header->func == DONE_CONF) ||
((header->func == ABORT) &&
(group->phase != PHASE_REGISTERED)))) {
glog1(group, "Rejecting %s message from %s: not encrypted",
func_name(header->func), rxname);
continue;
}
func = (uint8_t *)&header->func;
message = buf + sizeof(struct uftp_h);
meslen = packetlen - sizeof(struct uftp_h);
}
if (group != NULL) {
new_grtt = unquantize_grtt(header->grtt);
if (fabs(new_grtt - group->grtt) > 0.001) {
group->grtt = new_grtt;
set_timeout(group, 1);
}
group->gsize = unquantize_gsize(header->gsize);
glog5(group, "grtt: %.3f", group->grtt);
}
if (header->func == PROXY_KEY) {
handle_proxy_key(&src, message, meslen);
continue;
}
if (header->func == HB_RESP) {
handle_hb_response(listener, &src, message, meslen, hb_hosts,
hbhost_count, privkey[0], privkey_type[0], uid);
continue;
}
if (header->func == ANNOUNCE) {
// Ignore any ANNOUNCE for a group we're already handling
if (group == NULL) {
handle_announce(&src, buf, packetlen, rxtime);
} else if (group->phase == PHASE_MIDGROUP) {
// Make sure we don't time out while waiting for other
// clients to register with the server.
set_timeout(group, 0);
}
} else {
if (group == NULL) {
// group / file ID not in list
continue;
}
if (group->version != version) {
glog1(group, "Version mismatch");
continue;
}
if (group->src_id != header->src_id) {
glog1(group, "Source ID mismatch");
continue;
}
if (*func == ABORT) {
handle_abort(group, message, meslen);
continue;
}
switch (group->phase) {
case PHASE_REGISTERED:
if (group->keytype != KEY_NONE) {
if (*func == KEYINFO) {
handle_keyinfo(group, message, meslen, header->src_id);
} else {
glog1(group, "Expected KEYINFO, got %s",
func_name(*func));
}
} else if (group->keytype == KEY_NONE) {
if (*func == REG_CONF) {
handle_regconf(group, message, meslen);
} else if (*func == FILEINFO) {
handle_fileinfo(group, message, meslen, rxtime);
} else {
glog1(group, "Expected REG_CONF, got %s",
func_name(*func));
}
}
break;
case PHASE_MIDGROUP:
if (*func == FILEINFO) {
handle_fileinfo(group, message, meslen, rxtime);
} else if (*func == KEYINFO) {
handle_keyinfo(group, message, meslen, header->src_id);
} else if (*func == DONE) {
handle_done(group, message, meslen);
} else {
// Other clients may be still getting earlier files or
// setting up, so silently ignore anything unexpected
// and reset the timeout.
set_timeout(group, 0);
}
break;
case PHASE_RECEIVING:
if (*func == FILEINFO) {
handle_fileinfo(group, message, meslen, rxtime);
} else if (*func == FILESEG) {
handle_fileseg(group, message, meslen, txseq);
} else if (*func == DONE) {
handle_done(group, message, meslen);
} else if (*func == CONG_CTRL) {
handle_cong_ctrl(group, message, meslen, rxtime);
}
break;
case PHASE_COMPLETE:
if (*func == DONE_CONF) {
handle_done_conf(group, message, meslen);
}
break;
}
}
}
}
/**
* Reads an expected FILESEG and writes it to the proper place in the file
*/
void handle_fileseg(struct group_list_t *group, const unsigned char *message,
unsigned meslen, uint16_t txseq)
{
const struct fileseg_h *fileseg;
const struct tfmcc_data_info_he *tfmcc;
const unsigned char *data;
const uint8_t *he;
int datalen, section, cache_offset, status_idx;
uint32_t seq, i;
unsigned extlen;
if (group->fileinfo.ftype != FTYPE_REG) {
glog2(group, "Rejecting FILESEG: not a regular file");
return;
}
fileseg = (const struct fileseg_h *)message;
data = message + (fileseg->hlen * 4);
datalen = meslen - (fileseg->hlen * 4);
if ((meslen < (fileseg->hlen * 4U)) ||
((fileseg->hlen * 4U) < sizeof(struct fileseg_h))) {
glog2(group, "Rejecting FILESEG: invalid message size");
return;
}
if (ntohs(fileseg->file_id) != group->file_id) {
glog2(group, "Rejecting FILESEG: got incorrect file_id %04X",
ntohs(fileseg->file_id));
return;
}
tfmcc = NULL;
if (fileseg->hlen * 4U > sizeof(struct fileseg_h)) {
he = (const uint8_t *)fileseg + sizeof(struct fileseg_h);
if (*he == EXT_TFMCC_DATA_INFO) {
tfmcc = (const struct tfmcc_data_info_he *)he;
extlen = tfmcc->extlen * 4U;
if ((extlen > (fileseg->hlen * 4U) - sizeof(struct fileseg_h)) ||
extlen < sizeof(struct tfmcc_data_info_he)) {
glog2(group, "Rejecting FILESEG: invalid extension size");
return;
}
}
}
section = ntohs(fileseg->section);
if (section >= group->fileinfo.big_sections) {
seq = (group->fileinfo.big_sections * group->fileinfo.secsize_big) +
((section - group->fileinfo.big_sections) *
group->fileinfo.secsize_small) + ntohs(fileseg->sec_block);
} else {
seq = (section * group->fileinfo.secsize_big) +
ntohs(fileseg->sec_block);
}
if ((datalen != group->blocksize) &&
(seq != group->fileinfo.blocks - 1)) {
glog2(group, "Rejecting FILESEG: invalid data size %d", datalen);
return;
}
if (log_level >= 5) {
glog5(group, "Got packet %d", seq);
} else if (log_level == 4) {
if (seq != group->fileinfo.last_block + 1) {
glog4(group, "Got packet %d, last was %d",
seq, group->fileinfo.last_block);
}
}
if ((group->cc_type == CC_TFMCC) && tfmcc) {
handle_tfmcc_data_info(group, tfmcc);
}
group->fileinfo.got_data = 1;
group->fileinfo.last_block = seq;
if (txseq == group->max_txseq) {
if ((section > group->fileinfo.last_section) &&
(group->fileinfo.nak_time.tv_sec == 0)) {
// Start timer to send NAKs
gettimeofday(&group->fileinfo.nak_time, NULL);
add_timeval_d(&group->fileinfo.nak_time, 1 * group->grtt);
group->fileinfo.nak_section_first = group->fileinfo.last_section;
group->fileinfo.nak_section_last = section;
group->fileinfo.got_done = 0;
glog3(group, "New section, set NAK timer for sections %d - %d",
group->fileinfo.nak_section_first,
group->fileinfo.nak_section_last);
}
group->fileinfo.last_section = section;
}
if (group->fileinfo.naklist[seq]) {
if ((seq >= group->fileinfo.cache_start) &&
(seq <= group->fileinfo.cache_end + MAXMISORDER)) {
cache_offset=(seq - group->fileinfo.cache_start) * group->blocksize;
if (seq > group->fileinfo.cache_end) {
if ((cache_offset + datalen) > cache_len) {
glog4(group, "Disk cache full, flushing");
if (!flush_disk_cache(group)) {
return;
}
cache_offset = (seq - group->fileinfo.cache_start) *
group->blocksize;
} else {
for (i = group->fileinfo.cache_end; i <= seq; i++) {
if (!group->fileinfo.naklist[i]) {
glog3(group, "Cache gap seq %d "
"already received, flushing", i);
if (!flush_disk_cache(group)) {
return;
}
group->fileinfo.cache_start = seq;
cache_offset = 0;
break;
}
}
group->fileinfo.cache_end = seq;
}
}
} else {
if (group->fileinfo.cache_len != 0) {
glog3(group, "Seq %d out of cache range, flushing", seq);
if (!flush_disk_cache(group)) {
return;
}
}
cache_offset = 0;
group->fileinfo.cache_start = seq;
group->fileinfo.cache_end = seq;
}
group->fileinfo.cache_len = ((group->fileinfo.cache_end -
group->fileinfo.cache_start) * group->blocksize) + datalen;
status_idx = seq - group->fileinfo.cache_start;
if (group->fileinfo.cache_len > cache_len) {
glog0(group, "Cache overrun: "
"current cache len = %d, status_idx = %d",
group->fileinfo.cache_len, status_idx);
}
group->fileinfo.cache_status[status_idx] = 1;
memcpy(&group->fileinfo.cache[cache_offset], data, datalen);
}
set_timeout(group, 0);
}
/**
* Creates all directories in the given file's path, removing existing files.
* Returns 1 on success, 0 on failure
*/
int create_path_to_file(struct group_list_t *group, const char *filename)
{
char *dir, *base;
stat_struct statbuf;
int rval;
split_path(filename, &dir, &base);
if (!dir) {
glog1(group, "Invalid path element %s", filename);
rval = 0;
goto end;
}
#ifdef WINDOWS
if ((base == NULL) || ((strlen(dir) == 2) && (dir[1] == ':'))) {
#else
if ((!strcmp(dir, ".")) || (!strcmp(dir, "/"))) {
#endif
// At top level directory, so stop recursion
rval = 1;
goto end;
}
if (lstat_func(dir, &statbuf) != -1) {
if (!S_ISDIR(statbuf.st_mode)) {
if (unlink(dir) == -1) {
gsyserror(group, "Failed to delete path element %s", dir);
rval = 0;
goto end;
}
if (mkdir(dir, 0755) == -1) {
gsyserror(group, "Failed to create path element %s", dir);
rval = 0;
goto end;
}
}
} else {
// If the file's directory does not exist, recurse first to make sure
// all parent directories exist
if (!create_path_to_file(group, dir)) {
rval = 0;
goto end;
}
if (mkdir(dir, 0755) == -1) {
gsyserror(group, "Failed to create path element %s", dir);
rval = 0;
goto end;
}
}
rval = 1;
end:
free(dir);
free(base);
return rval;
}
void new_loss_event(struct group_list_t *group, uint16_t txseq)
{
uint32_t seq_long;
uint16_t count;
int bytes, avgbytes, rate, grtt_usec;
glog4(group, "Seq %d starts new loss event", txseq);
// Found a new loss event
if (txseq < group->max_txseq - MAXMISORDER) {
glog5(group, "wrap check, i=%u, maxseq=%u", txseq, group->max_txseq);
seq_long = ((group->seq_wrap - 1) << 16) | txseq;
} else {
seq_long = (group->seq_wrap << 16) | txseq;
}
if (group->slowstart) {
group->slowstart = 0;
// Initialize loss history
count = group->max_txseq;
bytes = 0;
grtt_usec = (int)(group->grtt * 1000000);
while ((count != group->start_txseq) &&
(diff_usec(group->loss_history[txseq].t,
group->loss_history[count].t) < grtt_usec)) {
bytes += group->loss_history[count--].size;
}
rate = (int)(bytes / group->grtt);
glog4(group, "End slowstart, calculated rate = %d", rate);
avgbytes= bytes / ((int16_t)(group->max_txseq - count));
group->loss_events[0].len = (int)(0 + pow(
(rate * ((group->rtt != 0) ? group->rtt : group->grtt)) /
(sqrt(1.5) * 8 * avgbytes), 2));
glog4(group, "Calculated prior event len = %d (rtt=%f, avgbytes=%d)",
group->loss_events[0].len, group->rtt,avgbytes);
} else {
group->loss_events[0].len = seq_long - group->loss_events[0].start_seq;
glog4(group, "Prior event length = %d (i=%u, start=%u)",
group->loss_events[0].len,
seq_long, group->loss_events[0].start_seq);
}
memmove(&group->loss_events[1], &group->loss_events[0],
sizeof(struct loss_event_t) * 8);
group->loss_events[0].start_seq = seq_long;
group->loss_events[0].len = 0;
group->loss_events[0].t = group->loss_history[txseq].t;
}
/**
* Updates the group's loss history
*
* Packets older than MAXMISORDER sequence numbers don't change the loss
* history, and packets aren't considered lost unless the sequence number is
* more than MAXMISORDER sequence numbers old. Works under the assumption
* that no more than 32K packets in a row get lost.
*/
void update_loss_history(struct group_list_t *group, uint16_t txseq, int size,
int ecn)
{
uint16_t i;
int tdiff, grtt_usec;
struct timeval tvdiff;
group->loss_history[txseq].found = 1;
gettimeofday(&group->loss_history[txseq].t, NULL);
if (group->multi.ss.ss_family == AF_INET6) {
group->loss_history[txseq].size = size + 8 + 40;
} else {
group->loss_history[txseq].size = size + 8 + 20;
}
if ((int16_t)(txseq - group->max_txseq) > 0) {
glog4(group, "Got seq %d, max was %d", txseq, group->max_txseq);
grtt_usec = (int)(group->grtt * 1000000);
if (txseq < group->max_txseq) {
glog5(group, "increasing seq_wrap, txseq=%u, maxseq=%u",
txseq, group->max_txseq);
group->seq_wrap++;
}
// First set nominal arrival times of missed packets
for (i = group->max_txseq + 1; i != txseq; i++) {
tdiff = (int)diff_usec(group->loss_history[txseq].t,
group->loss_history[group->max_txseq].t) *
((i - group->max_txseq) / (txseq - group->max_txseq));
tvdiff.tv_sec = 0;
tvdiff.tv_usec = tdiff;
while (tvdiff.tv_usec >= 1000000) {
tvdiff.tv_usec -= 1000000;
tvdiff.tv_sec++;
}
group->loss_history[i].found = 0;
group->loss_history[i].t =
add_timeval(group->loss_history[group->max_txseq].t,tvdiff);
}
// Then check for missed packets up to MAXMISORDER less than the current
// Don't do this part unless we have at least MAXMISORDER packets
// TODO: address issue of start_txseq being within MAXMISORDER sequence
// numbers from the maximum
if (group->seq_wrap ||((uint16_t)(group->max_txseq -
group->start_txseq) >= MAXMISORDER)) {
for (i = group->max_txseq - MAXMISORDER;
i != (uint16_t)(txseq - MAXMISORDER); i++) {
if (!group->loss_history[i].found &&
((diff_usec(group->loss_history[i].t,
group->loss_events[0].t) > grtt_usec) ||
group->slowstart)) {
new_loss_event(group, i);
}
}
}
group->max_txseq = txseq;
if (ecn) {
glog4(group, "Seq %d marked by ECN", txseq);
if ((diff_usec(group->loss_history[txseq].t,
group->loss_events[0].t) > grtt_usec) || group->slowstart) {
new_loss_event(group, txseq);
}
}
}
group->loss_events[0].len = ((group->seq_wrap << 16) | group->max_txseq) -
group->loss_events[0].start_seq;
glog5(group, "current cc len = %d", group->loss_events[0].len);
glog5(group, "seq_wrap=%d, max_txseq=%u, start_seq=%u",
group->seq_wrap, group->max_txseq, group->loss_events[0].start_seq);
}
