static void
roaming_auth_required(void)
{
u_char digest[SSH_DIGEST_MAX_LENGTH];
Buffer b;
u_int64_t chall, oldchall;
chall = packet_get_int64();
oldchall = packet_get_int64();
if (oldchall != lastseenchall) {
key1 = oldkey1;
key2 = oldkey2;
}
lastseenchall = chall;
buffer_init(&b);
buffer_put_int64(&b, cookie);
buffer_put_int64(&b, chall);
if (ssh_digest_buffer(SSH_DIGEST_SHA1, &b, digest, sizeof(digest)) != 0)
fatal("%s: ssh_digest_buffer failed", __func__);
buffer_free(&b);
packet_start(SSH2_MSG_KEX_ROAMING_AUTH);
packet_put_int64(key1 ^ get_recv_bytes());
packet_put_raw(digest, ssh_digest_bytes(SSH_DIGEST_SHA1));
packet_send();
oldkey1 = key1;
oldkey2 = key2;
calculate_new_key(&key1, cookie, chall);
calculate_new_key(&key2, cookie, chall);
debug("Received %llu bytes", (unsigned long long)get_recv_bytes());
debug("Sent roaming_auth packet");
}
void
roaming_reply(int type, u_int32_t seq, void *ctxt)
{
if (type == SSH2_MSG_REQUEST_FAILURE) {
logit("Server denied roaming");
return;
}
verbose("Roaming enabled");
roaming_id = packet_get_int();
cookie = packet_get_int64();
key1 = oldkey1 = packet_get_int64();
key2 = oldkey2 = packet_get_int64();
set_out_buffer_size(packet_get_int() + get_snd_buf_size());
roaming_enabled = 1;
}
static void
roaming_auth_required(void)
{
u_char digest[SHA_DIGEST_LENGTH];
EVP_MD_CTX md;
Buffer b;
const EVP_MD *evp_md = EVP_sha1();
u_int64_t chall, oldchall;
chall = packet_get_int64();
oldchall = packet_get_int64();
if (oldchall != lastseenchall) {
key1 = oldkey1;
key2 = oldkey2;
}
lastseenchall = chall;
buffer_init(&b);
buffer_put_int64(&b, cookie);
buffer_put_int64(&b, chall);
EVP_DigestInit(&md, evp_md);
EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b));
EVP_DigestFinal(&md, digest, NULL);
buffer_free(&b);
packet_start(SSH2_MSG_KEX_ROAMING_AUTH);
packet_put_int64(key1 ^ get_recv_bytes());
packet_put_raw(digest, sizeof(digest));
packet_send();
oldkey1 = key1;
oldkey2 = key2;
calculate_new_key(&key1, cookie, chall);
calculate_new_key(&key2, cookie, chall);
#ifdef WIN32_FIXME
debug("Received %I64u bytes", (unsigned long long)get_recv_bytes());
#else
debug("Received %llu bytes", (unsigned long long)get_recv_bytes());
#endif
debug("Sent roaming_auth packet");
}
static int
roaming_resume(void)
{
u_int64_t recv_bytes;
char *str = NULL, *kexlist = NULL, *c;
int i, type;
int timeout_ms = options.connection_timeout * 1000;
u_int len;
u_int32_t rnd = 0;
resume_in_progress = 1;
/* Exchange banners */
ssh_exchange_identification(timeout_ms);
packet_set_nonblocking();
/* Send a kexinit message with [email protected] as only kex algo */
packet_start(SSH2_MSG_KEXINIT);
for (i = 0; i < KEX_COOKIE_LEN; i++) {
if (i % 4 == 0)
rnd = arc4random();
packet_put_char(rnd & 0xff);
rnd >>= 8;
}
packet_put_cstring(KEX_RESUME);
for (i = 1; i < PROPOSAL_MAX; i++) {
/* kex algorithm added so start with i=1 and not 0 */
packet_put_cstring(""); /* Not used when we resume */
}
packet_put_char(1); /* first kex_packet follows */
packet_put_int(0); /* reserved */
packet_send();
/* Assume that [email protected] will be accepted */
packet_start(SSH2_MSG_KEX_ROAMING_RESUME);
packet_put_int(roaming_id);
packet_send();
/* Read the server's kexinit and check for [email protected] */
if ((type = packet_read()) != SSH2_MSG_KEXINIT) {
debug("expected kexinit on resume, got %d", type);
goto fail;
}
for (i = 0; i < KEX_COOKIE_LEN; i++)
(void)packet_get_char();
kexlist = packet_get_string(&len);
if (!kexlist
|| (str = match_list(KEX_RESUME, kexlist, NULL)) == NULL) {
debug("server doesn't allow resume");
goto fail;
}
free(str);
for (i = 1; i < PROPOSAL_MAX; i++) {
/* kex algorithm taken care of so start with i=1 and not 0 */
free(packet_get_string(&len));
}
i = packet_get_char(); /* first_kex_packet_follows */
if (i && (c = strchr(kexlist, ',')))
*c = 0;
if (i && strcmp(kexlist, KEX_RESUME)) {
debug("server's kex guess (%s) was wrong, skipping", kexlist);
(void)packet_read(); /* Wrong guess - discard packet */
}
/*
* Read the ROAMING_AUTH_REQUIRED challenge from the server and
* send ROAMING_AUTH
*/
if ((type = packet_read()) != SSH2_MSG_KEX_ROAMING_AUTH_REQUIRED) {
debug("expected roaming_auth_required, got %d", type);
goto fail;
}
roaming_auth_required();
/* Read ROAMING_AUTH_OK from the server */
if ((type = packet_read()) != SSH2_MSG_KEX_ROAMING_AUTH_OK) {
debug("expected roaming_auth_ok, got %d", type);
goto fail;
}
recv_bytes = packet_get_int64() ^ oldkey2;
debug("Peer received %llu bytes", (unsigned long long)recv_bytes);
resend_bytes(packet_get_connection_out(), &recv_bytes);
resume_in_progress = 0;
session_resumed = 1; /* Tell clientloop */
return 0;
fail:
free(kexlist);
if (packet_get_connection_in() == packet_get_connection_out())
close(packet_get_connection_in());
else {
close(packet_get_connection_in());
close(packet_get_connection_out());
}
return 1;
}
