/**
* 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;
}
}
}
}
/**
* This is the main message reading loop. Messages are read, validated,
* decrypted if necessary, then passed to the appropriate routine for handling.
*/
void mainloop()
{
struct uftp_h *header;
struct uftp2_h *v2_header;
unsigned char *buf, *decrypted, *message;
unsigned int decryptlen, meslen, expectedlen;
int packetlen, listidx, i;
uint8_t version, *func;
uint32_t v2func;
struct sockaddr_in src;
struct timeval *tv;
const int bsize = 9000; // Roughly size of ethernet jumbo frame
log0(0, 0, "%s", VERSIONSTR);
for (i = 0; i < key_count; i++) {
log1(0, 0, "Loaded key with fingerprint %s",
print_key_fingerprint(privkey[i]));
}
buf = calloc(bsize, 1);
decrypted = calloc(bsize, 1);
if ((buf == NULL) || (decrypted == NULL)){
syserror(0, 0, "calloc failed!");
exit(1);
}
header = (struct uftp_h *)buf;
v2_header = (struct uftp2_h *)buf;
while (1) {
tv = getrecenttimeout();
if (read_packet(listener, &src, buf, &packetlen,
bsize, tv) <= 0) {
continue;
}
if ((header->uftp_id == UFTP_VER_NUM) ||
(header->uftp_id == UFTP_3_0_VER)) {
version = header->uftp_id;
expectedlen = sizeof(struct uftp_h) + ntohs(header->blsize);
listidx = find_file(ntohl(header->group_id));
} else if (ntohl(v2_header->uftp_id) == V2_UFTP_ID) {
version = UFTP_V2_VER;
expectedlen = V2_PACKETSIZE;
listidx = find_file(ntohl(v2_header->tx_id));
v2func = ntohl(v2_header->func);
} else {
log(0, 0, "Invalid message from %s: not uftp packet "
"or invalid version", inet_ntoa(src.sin_addr));
continue;
}
if (packetlen != expectedlen) {
log(0, 0, "Invalid packet size from %s: got %d, expected %d",
inet_ntoa(src.sin_addr), packetlen, expectedlen);
continue;
}
if (((version == UFTP_VER_NUM) || (version == UFTP_3_0_VER)) &&
(header->func == ENCRYPTED) && (listidx != -1) &&
(group_list[listidx].keytype != KEY_NONE)) {
if (group_list[listidx].phase == PHASE_REGISTERED) {
log(ntohl(header->group_id), 0, "Got encrypted packet from %s "
"but keys not established", inet_ntoa(src.sin_addr));
}
if (!validate_and_decrypt(buf, &decrypted, &decryptlen,
group_list[listidx].mtu, group_list[listidx].keytype,
group_list[listidx].groupkey, group_list[listidx].groupsalt,
group_list[listidx].ivlen, group_list[listidx].hashtype,
group_list[listidx].grouphmackey,
group_list[listidx].hmaclen, group_list[listidx].sigtype,
group_list[listidx].serverkey,
group_list[listidx].server_keylen)) {
log(ntohl(header->group_id), 0, "Rejecting message from %s: "
"decrypt/validate failed", inet_ntoa(src.sin_addr));
continue;
}
func = (uint8_t *)decrypted;
message = decrypted;
meslen = decryptlen;
} else if ((version == UFTP_VER_NUM) || (version == UFTP_3_0_VER)) {
if ((listidx != -1) && (group_list[listidx].keytype != KEY_NONE) &&
((header->func == FILEINFO) || (header->func == FILESEG) ||
(header->func == DONE) || (header->func == DONE_CONF) ||
((header->func == ABORT) &&
(group_list[listidx].phase != PHASE_REGISTERED)))) {
log(0, 0, "Rejecting %s message from %s: not encrypted",
func_name(header->func), inet_ntoa(src.sin_addr));
continue;
}
func = (uint8_t *)&header->func;
message = buf + sizeof(struct uftp_h);
meslen = ntohs(header->blsize);
} else {
// Version 2
message = buf;
meslen = V2_PACKETSIZE;
}
if (((version == UFTP_VER_NUM) || (version == UFTP_3_0_VER)) &&
(header->func == PROXY_KEY)) {
handle_proxy_key(&src, buf);
continue;
}
if (((version == UFTP_VER_NUM) || (version == UFTP_3_0_VER)) &&
(header->func == HB_RESP)) {
handle_hb_response(listener, &src, buf, hb_hosts, hbhost_count,
noname, privkey[0]);
continue;
}
if ((((version == UFTP_VER_NUM) || (version == UFTP_3_0_VER)) &&
(header->func == ANNOUNCE)) ||
((version == UFTP_V2_VER) && (v2func == V2_ANNOUNCE))) {
// Ignore any ANNOUNCE for a group we're already handling
if (listidx == -1) {
handle_announce(src, version, buf);
} else if (group_list[listidx].phase == PHASE_MIDGROUP) {
// Make sure we don't time out while waiting for other
// clients to register with the server.
set_timeout(listidx);
}
} else {
if (listidx == -1) {
// group / file ID not in list
continue;
}
if (group_list[listidx].version != version) {
log(group_list[listidx].group_id, group_list[listidx].file_id,
"Version mismatch");
continue;
}
if ((((version == UFTP_VER_NUM) || (version == UFTP_3_0_VER)) &&
(*func == ABORT)) ||
((version == UFTP_V2_VER) && (v2func == V2_ABORT))) {
handle_abort(listidx, message, meslen);
continue;
}
switch (group_list[listidx].phase) {
case PHASE_REGISTERED:
if (version == UFTP_V2_VER) {
// This is repeated in one of the cases below, but it's
// separated out anyway to keep the V2 stuff separate.
handle_regconf(listidx, message, meslen);
} else if (group_list[listidx].keytype != KEY_NONE) {
if (*func == KEYINFO) {
handle_keyinfo(listidx, buf);
} else {
log(group_list[listidx].group_id,
group_list[listidx].file_id,
"Expected KEYINFO, got %s", func_name(*func));
}
} else if (group_list[listidx].keytype == KEY_NONE) {
if (*func == REG_CONF) {
handle_regconf(listidx, message, meslen);
} else if (*func == FILEINFO) {
handle_fileinfo(listidx, message, meslen);
} else {
log(group_list[listidx].group_id,
group_list[listidx].file_id,
"Expected REG_CONF, got %s", func_name(*func));
}
}
break;
case PHASE_MIDGROUP:
if (((version == UFTP_VER_NUM) || (version == UFTP_3_0_VER)) &&
(*func == FILEINFO)) {
handle_fileinfo(listidx, message, meslen);
} else if (((version == UFTP_VER_NUM) ||
(version == UFTP_3_0_VER)) && (*func == KEYINFO)) {
handle_keyinfo(listidx, buf);
} else if (((version == UFTP_V2_VER) && (v2func == V2_DONE)) ||
(((version == UFTP_VER_NUM) ||
(version == UFTP_3_0_VER)) && (*func == DONE))) {
handle_done(listidx, 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(listidx);
}
break;
case PHASE_RECEIVING:
if (((version == UFTP_VER_NUM) || (version == UFTP_3_0_VER)) &&
(*func == FILEINFO)) {
handle_fileinfo(listidx, message, meslen);
} else if (((version == UFTP_V2_VER) &&
(v2func == V2_FILESEG)) ||
(((version == UFTP_VER_NUM) ||
(version == UFTP_3_0_VER)) && (*func == FILESEG))) {
handle_fileseg(listidx, message, meslen);
} else if (((version == UFTP_V2_VER) && (v2func == V2_DONE)) ||
(((version == UFTP_VER_NUM) ||
(version == UFTP_3_0_VER)) && (*func == DONE))) {
handle_done(listidx, message, meslen);
}
break;
case PHASE_COMPLETE:
if (((version == UFTP_V2_VER) && (v2func == V2_DONE_CONF)) ||
(((version == UFTP_VER_NUM) ||
(version == UFTP_3_0_VER)) && (*func == DONE_CONF))) {
handle_done_conf(listidx, message, meslen);
}
break;
}
}
}
}