/
client_announce.c
executable file
·1110 lines (1010 loc) · 40.7 KB
/
client_announce.c
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/*
* UFTP - UDP based FTP with multicast
*
* Copyright (C) 2001-2015 Dennis A. Bush, Jr. bush@tcnj.edu
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Additional permission under GNU GPL version 3 section 7
*
* If you modify this program, or any covered work, by linking or
* combining it with the OpenSSL project's OpenSSL library (or a
* modified version of that library), containing parts covered by the
* terms of the OpenSSL or SSLeay licenses, the copyright holder
* grants you additional permission to convey the resulting work.
* Corresponding Source for a non-source form of such a combination
* shall include the source code for the parts of OpenSSL used as well
* as that of the covered work.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <errno.h>
#ifdef WINDOWS
#include <ws2tcpip.h>
#include <io.h>
#include <direct.h>
#include "win_func.h"
#else // if WINDOWS
#include <sys/socket.h>
#include <sys/time.h>
#include <netdb.h>
#endif
#include "client.h"
#include "client_common.h"
#include "client_announce.h"
/**
* Finds next open slot in the global group list.
* Returns a pointer to the open slot, or NULL if none found.
*/
struct group_list_t *find_open_slot(void)
{
int i;
for (i = 0; i < MAXLIST; i++) {
if (group_list[i].group_id == 0) {
memset(&group_list[i], 0, sizeof(group_list[i]));
return &group_list[i];
}
}
return NULL;
}
/**
* Returns the verify_data string used in certain messages. This value
* is then run through the PRF with the result going into the message.
*/
uint8_t *build_verify_data(struct group_list_t *group, int *verifylen)
{
uint8_t *verifydata;
uint32_t group_id;
int iplen;
iplen = (group->multi.ss.ss_family == AF_INET6) ?
sizeof(struct in6_addr) : sizeof(struct in_addr);
*verifylen = 0;
if (group->phase == PHASE_REGISTERED) {
verifydata = safe_calloc(sizeof(group->group_id) +
iplen + sizeof(group->rand1) +
sizeof(group->rand2) + sizeof(group->premaster), 1);
} else {
verifydata = safe_calloc(sizeof(group->group_id) +
iplen + sizeof(group->rand1) +
sizeof(group->rand2) + sizeof(group->premaster) +
PUBKEY_LEN + sizeof(group->groupmaster), 1);
}
group_id = htonl(group->group_id);
memcpy(verifydata, &group_id, sizeof(group_id));
*verifylen += sizeof(group_id);
if (group->multi.ss.ss_family == AF_INET6) {
memcpy(verifydata + *verifylen, &group->multi.sin6.sin6_addr.s6_addr,
iplen);
} else {
memcpy(verifydata + *verifylen, &group->multi.sin.sin_addr.s_addr,
iplen);
}
*verifylen += iplen;
memcpy(verifydata + *verifylen, group->rand1, sizeof(group->rand1));
*verifylen += sizeof(group->rand1);
memcpy(verifydata + *verifylen, group->rand2, sizeof(group->rand2));
*verifylen += sizeof(group->rand2);
memcpy(verifydata + *verifylen, group->premaster, group->premaster_len);
*verifylen += group->premaster_len;
if (group->phase != PHASE_REGISTERED) {
if (group->client_auth) {
uint16_t bloblen;
uint8_t *keyblob = verifydata + *verifylen;
if ((group->keyextype == KEYEX_RSA) ||
(group->keyextype == KEYEX_ECDH_RSA)) {
if (!export_RSA_key(group->client_privkey.rsa,
keyblob, &bloblen)) {
free(verifydata);
return NULL;
}
} else {
if (!export_EC_key(group->client_privkey.ec,
keyblob, &bloblen)) {
free(verifydata);
return NULL;
}
}
*verifylen += bloblen;
}
memcpy(verifydata + *verifylen, group->groupmaster,
sizeof(group->groupmaster));
*verifylen += sizeof(group->groupmaster);
}
return verifydata;
}
/**
* Sends a CLIENT_KEY message if the server requested it.
* Always sent right after a REGISTER.
*/
void send_client_key(struct group_list_t *group)
{
struct uftp_h *header;
struct client_key_h *client_key;
unsigned char *buf, *keyblob, *verify;
uint8_t *verifydata;
unsigned int siglen, meslen;
int verifylen;
uint16_t bloblen;
buf = safe_calloc(MAXMTU, 1);
header = (struct uftp_h *)buf;
client_key = (struct client_key_h *)(buf + sizeof(struct uftp_h));
keyblob = (unsigned char *)client_key + sizeof(struct client_key_h);
verifydata = build_verify_data(group, &verifylen);
if (!verifydata) {
glog0(group, "Error getting verify data");
send_abort(group, "Error getting verify data");
goto end;
}
set_uftp_header(header, CLIENT_KEY, group);
client_key->func = CLIENT_KEY;
if ((group->keyextype == KEYEX_RSA) ||
(group->keyextype == KEYEX_ECDH_RSA)) {
if (!export_RSA_key(group->client_privkey.rsa, keyblob, &bloblen)) {
glog0(group, "Error exporting public key");
send_abort(group, "Error exporting public key");
goto end;
}
verify = keyblob + bloblen;
if (!create_RSA_sig(group->client_privkey.rsa, group->hashtype,
verifydata, verifylen, verify, &siglen)) {
glog0(group, "Error signing verify data");
send_abort(group, "Error signing verify data");
goto end;
}
} else {
if (!export_EC_key(group->client_privkey.ec, keyblob, &bloblen)) {
glog0(group, "Error exporting public key");
send_abort(group, "Error exporting public key");
goto end;
}
verify = keyblob + bloblen;
if (!create_ECDSA_sig(group->client_privkey.ec, group->hashtype,
verifydata, verifylen, verify, &siglen)) {
glog0(group, "Error signing verify data");
send_abort(group, "Error signing verify data");
goto end;
}
}
client_key->bloblen = htons(bloblen);
client_key->siglen = htons(siglen);
client_key->hlen = (sizeof(struct client_key_h) + bloblen + siglen) / 4;
meslen = sizeof(struct uftp_h) + (client_key->hlen * 4);
if (nb_sendto(listener, buf, meslen, 0,
(struct sockaddr *)&(group->replyaddr),
family_len(group->replyaddr)) == SOCKET_ERROR) {
gsockerror(group, "Error sending CLIENT_KEY");
} else {
glog2(group, "CLIENT_KEY sent");
}
end:
free(verifydata);
free(buf);
}
/**
* Sends a REGISTER message in response to an ANNOUNCE or on timeout when
* waiting for a KEYINFO or REG_CONF. If the register timeout expired, abort.
*/
void send_register(struct group_list_t *group)
{
struct uftp_h *header;
struct register_h *reg;
unsigned char *buf, *keydata;
struct timeval now, send_time;
unsigned int len, meslen;
union key_t key;
gettimeofday(&now, NULL);
if (cmptimestamp(now, group->expire_time) >= 0) {
glog1(group, "Registration unconfirmed by server");
send_abort(group, "Registration unconfirmed");
return;
}
buf = safe_calloc(MAXMTU, 1);
header = (struct uftp_h *)buf;
reg = (struct register_h *)(buf + sizeof(struct uftp_h));
keydata = (unsigned char *)reg + sizeof(struct register_h);
set_uftp_header(header, REGISTER, group);
reg->func = REGISTER;
if (group->keytype != KEY_NONE) {
memcpy(reg->rand2, group->rand2, RAND_LEN);
if (group->keyextype == KEYEX_RSA) {
if (has_proxy) {
key = proxy_pubkey;
} else {
key = group->server_pubkey;
}
if (!RSA_encrypt(key.rsa, group->premaster, group->premaster_len,
keydata, &len)) {
glog0(group, "Error encrypting premaster secret");
send_abort(group, "Error encrypting premaster secret");
free(buf);
return;
}
} else {
uint16_t keylen;
if (!export_EC_key(group->client_dhkey.ec, keydata, &keylen)) {
glog0(group, "Error exporting ECDH public key");
send_abort(group, "Error exporting ECDH public key");
free(buf);
return;
}
len = keylen;
}
reg->keyinfo_len = htons(len);
} else {
len = 0;
}
gettimeofday(&now, NULL);
if (cmptimestamp(now, group->last_server_rx_ts) <= 0) {
send_time = group->last_server_ts;
} else {
send_time = add_timeval(group->last_server_ts,
diff_timeval(now, group->last_server_rx_ts));
}
reg->tstamp_sec = htonl((uint32_t)send_time.tv_sec);
reg->tstamp_usec = htonl((uint32_t)send_time.tv_usec);
reg->hlen = (sizeof(struct register_h) + len) / 4;
meslen = sizeof(struct uftp_h) + (reg->hlen * 4);
if (nb_sendto(listener, buf, meslen, 0,
(struct sockaddr *)&(group->replyaddr),
family_len(group->replyaddr)) == SOCKET_ERROR) {
gsockerror(group, "Error sending REGISTER");
} else {
glog2(group, "REGISTER sent");
}
glog3(group, "send time: %d.%06d", send_time.tv_sec, send_time.tv_usec);
set_timeout(group, 0);
if (group->client_auth) {
send_client_key(group);
}
free(buf);
}
/**
* Sends a KEYINFO_ACK in response to a KEYINFO
*/
void send_keyinfo_ack(struct group_list_t *group)
{
unsigned char *buf, *encrypted;
struct uftp_h *header;
struct keyinfoack_h *keyinfo_ack;
unsigned char *verifydata, *verify_hash, *verify_val;
unsigned int payloadlen, hashlen;
int verifylen, enclen, len;
buf = safe_calloc(MAXMTU, 1);
header = (struct uftp_h *)buf;
keyinfo_ack = (struct keyinfoack_h *)(buf + sizeof(struct uftp_h));
set_uftp_header(header, KEYINFO_ACK, group);
keyinfo_ack->func = KEYINFO_ACK;
keyinfo_ack->hlen = sizeof(struct keyinfoack_h) / 4;
verifydata = build_verify_data(group, &verifylen);
if (!verifydata) {
glog0(group, "Error getting verify data");
send_abort(group, "Error getting verify data");
free(buf);
return;
}
verify_hash = safe_calloc(group->hmaclen, 1);
verify_val = safe_calloc(VERIFY_LEN + group->hmaclen, 1);
hash(group->hashtype, verifydata, verifylen, verify_hash, &hashlen);
PRF(group->hashtype, VERIFY_LEN, group->groupmaster,
sizeof(group->groupmaster), "client finished",
verify_hash, hashlen, verify_val, &len);
memcpy(keyinfo_ack->verify_data, verify_val, VERIFY_LEN);
free(verifydata);
free(verify_hash);
free(verify_val);
payloadlen = sizeof(struct keyinfoack_h);
encrypted = NULL;
if (!encrypt_and_sign(buf, &encrypted, payloadlen, &enclen, group->keytype,
group->groupkey, group->groupsalt, &group->ivctr, group->ivlen,
group->hashtype, group->grouphmackey, group->hmaclen,group->sigtype,
group->keyextype, group->client_privkey,group->client_privkeylen)) {
glog0(group, "Error encrypting KEYINFO_ACK");
free(buf);
return;
}
payloadlen = enclen + sizeof(struct uftp_h);
if (nb_sendto(listener, encrypted, payloadlen, 0,
(struct sockaddr *)&(group->replyaddr),
family_len(group->replyaddr)) == SOCKET_ERROR) {
gsockerror(group, "Error sending KEYINFO_ACK");
} else {
glog2(group, "KEYINFO_ACK sent");
}
free(encrypted);
free(buf);
}
/**
* Sends a FILEINFO_ACK in response to a FILEINFO
*/
void send_fileinfo_ack(struct group_list_t *group, int restart)
{
unsigned char *buf, *encrypted, *outpacket;
struct uftp_h *header;
struct fileinfoack_h *fileinfo_ack;
struct timeval now, send_time;
unsigned int payloadlen;
int enclen;
buf = safe_calloc(MAXMTU, 1);
header = (struct uftp_h *)buf;
fileinfo_ack = (struct fileinfoack_h *)(buf + sizeof(struct uftp_h));
payloadlen = sizeof(struct fileinfoack_h);
set_uftp_header(header, FILEINFO_ACK, group);
fileinfo_ack->func = FILEINFO_ACK;
fileinfo_ack->hlen = sizeof(struct fileinfoack_h) / 4;
fileinfo_ack->file_id = htons(group->file_id);
if (restart) {
fileinfo_ack->flags |= FLAG_PARTIAL;
}
gettimeofday(&now, NULL);
if (cmptimestamp(now, group->last_server_rx_ts) <= 0) {
send_time = group->last_server_ts;
} else {
send_time = add_timeval(group->last_server_ts,
diff_timeval(now, group->last_server_rx_ts));
}
fileinfo_ack->tstamp_sec = htonl((uint32_t)send_time.tv_sec);
fileinfo_ack->tstamp_usec = htonl((uint32_t)send_time.tv_usec);
if (group->keytype != KEY_NONE) {
encrypted = NULL;
if (!encrypt_and_sign(buf, &encrypted, payloadlen, &enclen,
group->keytype, group->groupkey, group->groupsalt,&group->ivctr,
group->ivlen, group->hashtype, group->grouphmackey,
group->hmaclen, group->sigtype, group->keyextype,
group->client_privkey, group->client_privkeylen)) {
glog0(group, "Error encrypting FILEINFO_ACK");
free(buf);
return;
}
outpacket = encrypted;
payloadlen = enclen;
} else {
encrypted = NULL;
outpacket = buf;
}
payloadlen += sizeof(struct uftp_h);
if (nb_sendto(listener, outpacket, payloadlen, 0,
(struct sockaddr *)&(group->replyaddr),
family_len(group->replyaddr)) == SOCKET_ERROR) {
gsockerror(group, "Error sending FILEINFO_ACK");
} else {
glog2(group, "FILEINFO_ACK sent");
}
glog3(group, "send time: %d.%06d", send_time.tv_sec, send_time.tv_usec);
free(encrypted);
free(buf);
}
/**
* Verifies a server's public key fingerprint
*/
int verify_server_fingerprint(const unsigned char *keyblob, int bloblen,
struct group_list_t *group)
{
unsigned char fingerprint[HMAC_LEN];
unsigned int fplen;
int found, keyidx;
if (server_count == 0) {
return 1;
}
for (keyidx = 0, found = 0; (keyidx < server_count) && !found; keyidx++) {
if (server_keys[keyidx].uid == group->src_id) {
keyidx--;
found = 1;
}
}
if (!found) {
return 0;
}
if (!server_keys[keyidx].has_fingerprint) {
return 1;
}
hash(HASH_SHA1, keyblob, bloblen, fingerprint, &fplen);
if (memcmp(server_keys[keyidx].fingerprint, fingerprint, fplen)) {
return 0;
} else {
return 1;
}
}
/**
* Calculate the master key and do key expansion to determine the symmetric
* cypher key and IV salt, and hash key for the server
*/
int calculate_server_keys(struct group_list_t *group,
const struct enc_info_he *encinfo)
{
unsigned char *seed, *prf_buf;
int explen, len, seedlen;
time_t t;
uint32_t t2;
memcpy(group->rand1, encinfo->rand1, sizeof(encinfo->rand1));
if (!get_random_bytes(group->rand2, sizeof(group->rand2))) {
glog0(group, "Failed to get random bytes for rand2");
send_abort(group, "Failed to get random bytes for rand2");
return 0;
}
// Sets the first 4 bytes of rand2 to the current time
t = time(NULL);
t2 = (uint32_t)(t & 0xFFFFFFFF);
*(uint32_t *)(group->rand2) = t2;
if (group->keyextype == KEYEX_RSA) {
if (!get_random_bytes(group->premaster, MASTER_LEN)) {
glog0(group, "Failed to get random bytes for premaster");
send_abort(group, "Failed to get random bytes for premaster");
return 0;
}
group->premaster_len = MASTER_LEN;
} else {
EC_key_t pubecdh;
if (has_proxy) {
pubecdh = proxy_dhkey.ec;
} else {
pubecdh = group->server_dhkey.ec;
}
if (!get_ECDH_key(pubecdh, group->client_dhkey.ec,
group->premaster, &group->premaster_len)) {
glog0(group, "Failed to calculate ECDH key");
send_abort(group, "Failed to calculate ECDH key");
return 0;
}
}
get_key_info(group->keytype, &group->keylen, &group->ivlen);
group->hmaclen = get_hash_len(group->hashtype);
explen = group->keylen + SALT_LEN + group->hmaclen;
seedlen = RAND_LEN * 2;
seed = safe_calloc(seedlen, 1);
prf_buf = safe_calloc(MASTER_LEN + explen + group->hmaclen, 1);
memcpy(seed, group->rand1, sizeof(group->rand1));
memcpy(seed + sizeof(group->rand1), group->rand2, sizeof(group->rand2));
PRF(group->hashtype, MASTER_LEN, group->premaster, group->premaster_len,
"master secret", seed, seedlen, prf_buf, &len);
memcpy(group->master,prf_buf, sizeof(group->master));
PRF(group->hashtype, explen, group->master, sizeof(group->master),
"key expansion", seed, seedlen, prf_buf, &len);
memcpy(group->hmackey, prf_buf, group->hmaclen);
memcpy(group->key, prf_buf + group->hmaclen, group->keylen);
memcpy(group->salt, prf_buf + group->hmaclen + group->keylen, SALT_LEN);
free(seed);
free(prf_buf);
return 1;
}
/**
* Read encryption related fields from an ANNOUNCE
*/
int read_announce_encryption(struct group_list_t *group,
struct enc_info_he *encinfo,
const unsigned char *packet, int packetlen)
{
int keyextype, sigtype, keytype, i;
unsigned char *keys;
keys = (unsigned char *)encinfo + sizeof(struct enc_info_he);
// Sanity check the selected encryption parameters
if (!cipher_supported(encinfo->keytype)) {
glog1(group, "Keytype invalid or not supported here");
send_abort(group, "Keytype invalid or not supported here");
return 0;
}
if (!hash_supported(encinfo->hashtype)) {
glog1(group, "Hashtype invalid or not supported here");
send_abort(group, "Hashtype invalid or not supported here");
return 0;
}
keyextype = (encinfo->keyextype_sigtype & 0xF0) >> 4;
sigtype = encinfo->keyextype_sigtype & 0x0F;
if (((sigtype != SIG_HMAC) && (sigtype != SIG_KEYEX) &&
(sigtype != SIG_AUTHENC)) ||
((sigtype == SIG_AUTHENC) && (!is_auth_enc(encinfo->keytype)))) {
glog1(group, "Invalid sigtype specified");
send_abort(group, "Invalid sigtype specified");
return 0;
}
if ((keyextype != KEYEX_RSA) && (keyextype != KEYEX_ECDH_RSA) &&
(keyextype != KEYEX_ECDH_ECDSA)) {
glog1(group, "Invalid keyextype specified");
send_abort(group, "Invalid keyextype specified");
return 0;
}
group->keyextype = keyextype;
group->keytype = encinfo->keytype;
group->hashtype = encinfo->hashtype;
group->sigtype = sigtype;
group->client_auth = ((encinfo->flags & FLAG_CLIENT_AUTH) != 0);
if (!verify_server_fingerprint(keys, ntohs(encinfo->keylen), group)) {
glog1(group, "Failed to verify server key fingerprint");
send_abort(group, "Failed to verify server key fingerprint");
return 0;
}
if ((group->keyextype == KEYEX_RSA) ||
(group->keyextype == KEYEX_ECDH_RSA)) {
keytype = KEYBLOB_RSA;
} else {
keytype = KEYBLOB_EC;
}
// Load server key and select a matching client key
if (keytype == KEYBLOB_RSA) {
if (!import_RSA_key(&group->server_pubkey.rsa, keys,
ntohs(encinfo->keylen))) {
glog0(group, "Failed to load server public key");
send_abort(group, "Failed to load server public key");
return 0;
}
group->server_pubkeylen = RSA_keylen(group->server_pubkey.rsa);
for (i = 0; i < key_count; i++) {
if ((privkey_type[i] == KEYBLOB_RSA) &&
(group->server_pubkeylen == RSA_keylen(privkey[i].rsa))) {
group->client_privkey = privkey[i];
group->client_privkeylen = RSA_keylen(privkey[i].rsa);
break;
}
}
} else {
if (!import_EC_key(&group->server_pubkey.ec, keys,
ntohs(encinfo->keylen), 0)) {
glog0(group, "Failed to load server public key");
send_abort(group, "Failed to load server public key");
return 0;
}
group->server_pubkeylen = ECDSA_siglen(group->server_pubkey.ec);
for (i = 0; i < key_count; i++) {
if ((privkey_type[i] == KEYBLOB_EC) &&
(get_EC_curve(group->server_pubkey.ec) ==
get_EC_curve(privkey[i].ec))) {
group->client_privkey = privkey[i];
group->client_privkeylen = ECDSA_siglen(privkey[i].ec);
break;
}
}
}
if (!group->client_privkey.key) {
glog1(group, "No client key compatible with server key");
send_abort(group, "No client key compatible with server key");
return 0;
}
if (has_proxy) {
if (!proxy_pubkey.key) {
glog1(group, "Response proxy set but haven't gotten key yet");
send_abort(group,"Response proxy set but haven't gotten key yet");
return 0;
}
if (!(((keytype == KEYBLOB_RSA) && (proxy_pubkeytype == KEYBLOB_RSA)) &&
(RSA_keylen(group->server_pubkey.rsa) ==
RSA_keylen(proxy_pubkey.rsa))) &&
!(((keytype == KEYBLOB_EC) && (proxy_pubkeytype==KEYBLOB_EC)) &&
(get_EC_curve(group->server_pubkey.ec) ==
get_EC_curve(proxy_pubkey.ec)))) {
glog1(group, "Response proxy key not compatible with server key");
send_abort(group,
"Response proxy key not compatible with server key");
return 0;
}
}
if ((group->keyextype == KEYEX_ECDH_ECDSA) ||
(group->keyextype == KEYEX_ECDH_RSA)) {
unsigned char *sigcopy;
int siglen;
unsigned char *dhblob = keys + ntohs(encinfo->keylen);
unsigned char *sig = dhblob + ntohs(encinfo->dhlen);
if (!import_EC_key(&group->server_dhkey.ec, dhblob,
ntohs(encinfo->dhlen), 1)) {
glog0(group, "Failed to load server public ECDH key");
send_abort(group, "Failed to load server public ECDH key");
return 0;
}
group->client_dhkey.ec =
gen_EC_key(get_EC_curve(group->server_dhkey.ec), 1, NULL);
if (!group->client_dhkey.key) {
glog0(group, "Failed to generate client ECDH key");
send_abort(group, "Failed to generate client ECDH key");
return 0;
}
if (has_proxy) {
// We already checked if the proxy key exists, so no need to repeat
if (get_EC_curve(group->server_dhkey.ec) !=
get_EC_curve(proxy_dhkey.ec)) {
glog1(group, "Response proxy ECDH key "
"not compatible with server ECDH key");
send_abort(group, "Response proxy ECDH key "
"not compatible with server ECDH key");
return 0;
}
}
siglen = ntohs(encinfo->siglen);
sigcopy = safe_calloc(siglen, 1);
memcpy(sigcopy, sig, siglen);
memset(sig, 0, siglen);
if (keytype == KEYBLOB_RSA) {
if (!verify_RSA_sig(group->server_pubkey.rsa, group->hashtype,
packet, packetlen, sigcopy, siglen)) {
glog1(group, "Signature verification failed");
send_abort(group, "Signature verification failed");
free(sigcopy);
return 0;
}
} else {
if (!verify_ECDSA_sig(group->server_pubkey.ec, group->hashtype,
packet, packetlen, sigcopy, siglen)) {
glog1(group, "Signature verification failed");
send_abort(group, "Signature verification failed");
free(sigcopy);
return 0;
}
}
free(sigcopy);
}
// Calculate keys
if (!calculate_server_keys(group, encinfo)) {
return 0;
}
return 1;
}
/**
* Read in the contents of an ANNOUNCE.
*/
int read_announce(struct group_list_t *group, unsigned char *packet,
union sockaddr_u *src, struct timeval rxtime, int packetlen)
{
struct uftp_h *header;
struct announce_h *announce;
struct enc_info_he *encinfo;
uint8_t *publicmcast, *privatemcast;
uint8_t *he;
unsigned int iplen, extlen;
header = (struct uftp_h *)packet;
announce = (struct announce_h *)(packet + sizeof(struct uftp_h));
encinfo = NULL;
group->phase = PHASE_REGISTERED;
group->version = header->version;
group->group_id = ntohl(header->group_id);
group->group_inst = header->group_inst;
group->src_id = header->src_id;
if (has_proxy) {
group->replyaddr = proxy_info.addr;
} else {
group->replyaddr = *src;
}
group->grtt = unquantize_grtt(header->grtt);
group->rtt = 0;
group->robust = announce->robust;
group->cc_type = announce->cc_type;
group->gsize = unquantize_gsize(header->gsize);
group->blocksize = ntohs(announce->blocksize);
group->last_server_ts.tv_sec = ntohl(announce->tstamp_sec);
group->last_server_ts.tv_usec = ntohl(announce->tstamp_usec);
group->last_server_rx_ts = rxtime;
group->restart = ((group->group_inst != 0) && (strcmp(tempdir, "")));
group->sync_preview = ((announce->flags & FLAG_SYNC_PREVIEW) != 0);
group->sync_mode = group->sync_preview ||
((announce->flags & FLAG_SYNC_MODE) != 0);
iplen = ((announce->flags & FLAG_IPV6) != 0) ?
sizeof(struct in6_addr) : sizeof(struct in_addr);
publicmcast = ((uint8_t *)announce) + sizeof(struct announce_h);
privatemcast = publicmcast + iplen;
if ((announce->flags & FLAG_IPV6) != 0) {
group->multi.sin6.sin6_family = AF_INET6;
#ifdef SOCKADDR_LEN
group->multi.sin6.sin6_len = sizeof(struct sockaddr_in6);
#endif
memcpy(&group->multi.sin6.sin6_addr.s6_addr, privatemcast, iplen);
} else {
group->multi.sin.sin_family = AF_INET;
#ifdef SOCKADDR_LEN
group->multi.sin.sin_len = sizeof(struct sockaddr_in);
#endif
memcpy(&group->multi.sin.sin_addr.s_addr, privatemcast, iplen);
}
group->fileinfo.fd = -1;
if ((announce->hlen * 4U) < sizeof(struct announce_h) + (2U * iplen)) {
glog1(group, "Rejecting ANNOUNCE from %08X: invalid header size",
ntohl(group->src_id));
send_abort(group, "Invalid header size");
return 0;
}
if ((announce->hlen * 4U) > sizeof(struct announce_h) + (2U * iplen)) {
he = (unsigned char *)announce + sizeof(struct announce_h) +
(2U * iplen);
if (*he == EXT_ENC_INFO) {
encinfo = (struct enc_info_he *)he;
extlen = encinfo->extlen * 4U;
if ((extlen > ((announce->hlen * 4U) -
sizeof(struct announce_h))) ||
(extlen < sizeof(struct enc_info_he)) ||
(extlen != (sizeof(struct enc_info_he) +
ntohs(encinfo->keylen) + ntohs(encinfo->dhlen) +
ntohs(encinfo->siglen)))) {
glog1(group, "Rejecting ANNOUNCE from %08X: "
"invalid extension size", ntohl(group->src_id));
send_abort(group, "Invalid extension size");
return 0;
}
}
}
if (encinfo != NULL) {
if (!read_announce_encryption(group, encinfo, packet, packetlen)) {
return 0;
}
} else if (encrypted_only) {
glog1(group, "No unencrypted transfers allowed");
send_abort(group, "No unencrypted transfers allowed");
return 0;
} else {
group->keyextype = KEYEX_NONE;
group->keytype = KEY_NONE;
group->hashtype = HASH_NONE;
group->sigtype = SIG_NONE;
group->client_auth = 0;
}
gettimeofday(&group->expire_time, NULL);
if (4 * group->robust * group->grtt < 1.0) {
add_timeval_d(&group->expire_time, 1.0);
} else {
add_timeval_d(&group->expire_time, 4 * group->robust * group->grtt);
}
group->fileinfo.nak_time.tv_sec = 0;
group->fileinfo.nak_time.tv_usec = 0;
// Size of data packet, used in transmission speed calculations
group->datapacketsize = group->blocksize + sizeof(struct fileseg_h);
if (group->cc_type == CC_TFMCC) {
group->datapacketsize += sizeof(struct tfmcc_data_info_he);
}
if (group->keytype != KEY_NONE) {
group->datapacketsize += ((group->sigtype == SIG_KEYEX) ?
group->server_pubkeylen : (group->sigtype == SIG_HMAC) ?
group->hmaclen : 0) + KEYBLSIZE + sizeof(struct encrypted_h);
}
// 8 = UDP size, 20 = IPv4 size, 40 = IPv6 size
if ((announce->flags & FLAG_IPV6) != 0) {
group->datapacketsize += sizeof(struct uftp_h) + 8 + 40;
} else {
group->datapacketsize += sizeof(struct uftp_h) + 8 + 20;
}
if (group->cc_type != CC_NONE) {
group->loss_history= safe_calloc(0x10000,sizeof(struct loss_history_t));
group->slowstart = 1;
group->seq_wrap = 0;
group->start_txseq = ntohs(header->seq);
group->max_txseq = group->start_txseq;
group->loss_history[group->start_txseq].found = 1;
group->loss_history[group->start_txseq].t = rxtime;
group->loss_history[group->start_txseq].size = packetlen;
}
return 1;
}
/**
* Processes a new incoming ANNOUNCE
*/
void handle_announce(union sockaddr_u *src, unsigned char *packet,
unsigned packetlen, struct timeval rxtime)
{
struct uftp_h *header;
struct announce_h *announce;
uint32_t *addrlist;
int addrlen, rval;
struct group_list_t *group;
time_t t;
struct tm *start_time;
char privname[INET6_ADDRSTRLEN], srcname[INET6_ADDRSTRLEN];
char srcfqdn[DESTNAME_LEN];
header = (struct uftp_h *)packet;
announce = (struct announce_h *)(packet + sizeof(struct uftp_h));
addrlist = (uint32_t *)((unsigned char *)announce + (announce->hlen * 4));
addrlen = (packetlen - sizeof(struct uftp_h) - (announce->hlen * 4)) / 4;
if ((packetlen < sizeof(struct uftp_h) + (announce->hlen * 4U)) ||
((announce->hlen * 4U) < sizeof(struct announce_h))) {
log1(ntohl(header->group_id), header->group_inst, 0,
"Rejecting ANNOUNCE from %08X: invalid message size",
ntohl(header->src_id));
return;
}
if ((addrlen != 0) && (!uid_in_list(addrlist, addrlen))) {
log1(ntohl(header->group_id), header->group_inst, 0,
"Name not in host list");
return;
}
if ((group = find_open_slot()) == NULL ) {
log0(ntohl(header->group_id), header->group_inst, 0,
"Error: maximum number of incoming files exceeded: %d\n", MAXLIST);
return;
}
t = time(NULL);
start_time = localtime(&t);
snprintf(group->start_date, sizeof(group->start_date), "%04d%02d%02d",
start_time->tm_year + 1900,
start_time->tm_mon + 1, start_time->tm_mday);
snprintf(group->start_time, sizeof(group->start_time), "%02d%02d%02d",
start_time->tm_hour, start_time->tm_min, start_time->tm_sec);
if (!read_announce(group, packet, src, rxtime, packetlen)) {
return;
}
if ((rval = getnameinfo((struct sockaddr *)src, family_len(*src),
srcname, sizeof(srcname), NULL, 0, NI_NUMERICHOST)) != 0) {
glog1(group, "getnameinfo failed: %s", gai_strerror(rval));
}
if (!noname) {
if ((rval = getnameinfo((struct sockaddr *)src, family_len(*src),
srcfqdn, sizeof(srcfqdn), NULL, 0, 0)) != 0) {
glog1(group, "getnameinfo failed: %s", gai_strerror(rval));
}
} else {
strncpy(srcfqdn, srcname, sizeof(srcfqdn) - 1);
}
if ((rval = getnameinfo((struct sockaddr *)&group->multi,
family_len(group->multi), privname, sizeof(privname),
NULL, 0, NI_NUMERICHOST)) != 0) {
glog1(group, "getnameinfo failed: %s", gai_strerror(rval));
}
glog2(group, "Received request from %08X at %s (%s)",
ntohl(group->src_id), srcfqdn, srcname);
glog2(group, "Using private multicast address %s", privname);
glog3(group, "grtt = %.6f", group->grtt);
glog3(group, "send time: %d.%06d", group->last_server_ts.tv_sec,
group->last_server_ts.tv_usec);
glog3(group, "receive time: %d.%06d", group->last_server_rx_ts.tv_sec,
group->last_server_rx_ts.tv_usec);
if (status_file) {
fprintf(status_file,
"CONNECT;%04d/%02d/%02d-%02d:%02d:%02d;%08X;%08X;%s;%s\n",
start_time->tm_year + 1900, start_time->tm_mon + 1,
start_time->tm_mday, start_time->tm_hour,
start_time->tm_min, start_time->tm_sec,
ntohl(group->src_id), group->group_id, srcname, srcfqdn);
fflush(status_file);
}
if (group->restart) {
if (group->sync_mode) {
glog1(group, "Sync mode and restart mode incompatible");
send_abort(group, "Sync mode and restart mode incompatible");
return;
}
}
if (!addr_blank(&group->multi)) {
if (server_count > 0) {
if (!is_multicast(&group->multi, 1)) {
glog1(group, "Invalid source specific multicast address: %s",
privname);
send_abort(group, "Invalid source specific multicast address");
return;
}
if (!other_mcast_users(group)) {
if (!multicast_join(listener, group->group_id, &group->multi,
m_interface, interface_count,
server_keys, server_count)) {
send_abort(group, "Error joining multicast group");
return;
}
if (has_proxy) {
if (!multicast_join(listener,group->group_id, &group->multi,
m_interface, interface_count, &proxy_info, 1)) {
send_abort(group, "Error joining multicast group");
return;
}
}
}
} else {
if (!is_multicast(&group->multi, 0)) {
glog1(group, "Invalid multicast address: %s", privname);
send_abort(group, "Invalid multicast address");
return;
}
if (!other_mcast_users(group)) {
if (!multicast_join(listener, group->group_id,
&group->multi, m_interface, interface_count, NULL, 0)) {
send_abort(group, "Error joining multicast group");
return;
}
}
}
group->multi_join = 1;
}
send_register(group);
}
/**
* Processes an incoming REG_CONF message.
* Expected in response to a REGISTER when encryption is disabled.