{
unsigned char *in = (unsigned char *)vin;
struct do_ssh2_transport_state {
- int nbits, pbits, warn;
+ int nbits, pbits, warn_kex, warn_cscipher, warn_sccipher;
Bignum p, g, e, f, K;
int kex_init_value, kex_reply_value;
const struct ssh_mac **maclist;
struct Packet *pktout;
int dlgret;
int guessok;
+ int ignorepkt;
};
crState(do_ssh2_transport_state);
* to.
*/
{
- char *str;
+ char *str, *preferred;
int i, j, len;
if (pktin->type != SSH2_MSG_KEXINIT) {
s->scmac_tobe = NULL;
s->cscomp_tobe = NULL;
s->sccomp_tobe = NULL;
+ s->warn_kex = s->warn_cscipher = s->warn_sccipher = FALSE;
+
pktin->savedpos += 16; /* skip garbage cookie */
ssh_pkt_getstring(pktin, &str, &len); /* key exchange algorithms */
- s->warn = 0;
+
+ preferred = NULL;
for (i = 0; i < s->n_preferred_kex; i++) {
const struct ssh_kex *k = s->preferred_kex[i];
if (!k) {
- s->warn = 1;
- } else if (in_commasep_string(k->name, str, len)) {
- ssh->kex = k;
+ s->warn_kex = TRUE;
+ } else {
+ if (!preferred) preferred = k->name;
+ if (in_commasep_string(k->name, str, len))
+ ssh->kex = k;
}
- if (ssh->kex) {
- if (s->warn) {
- ssh_set_frozen(ssh, 1);
- s->dlgret = askalg(ssh->frontend, "key-exchange algorithm",
- ssh->kex->name,
- ssh_dialog_callback, ssh);
- if (s->dlgret < 0) {
- do {
- crReturn(0);
- if (pktin) {
- bombout(("Unexpected data from server while"
- " waiting for user response"));
- crStop(0);
- }
- } while (pktin || inlen > 0);
- s->dlgret = ssh->user_response;
- }
- ssh_set_frozen(ssh, 0);
- if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
- }
- }
+ if (ssh->kex)
break;
- }
}
if (!ssh->kex) {
bombout(("Couldn't agree a key exchange algorithm (available: %s)",
* the first algorithm in our list, even if it's still the algorithm
* we end up using.
*/
- s->guessok =
- first_in_commasep_string(s->preferred_kex[0]->name, str, len);
+ s->guessok = first_in_commasep_string(preferred, str, len);
ssh_pkt_getstring(pktin, &str, &len); /* host key algorithms */
for (i = 0; i < lenof(hostkey_algs); i++) {
if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
s->guessok = s->guessok &&
first_in_commasep_string(hostkey_algs[0]->name, str, len);
ssh_pkt_getstring(pktin, &str, &len); /* client->server cipher */
- s->warn = 0;
for (i = 0; i < s->n_preferred_ciphers; i++) {
const struct ssh2_ciphers *c = s->preferred_ciphers[i];
if (!c) {
- s->warn = 1;
+ s->warn_cscipher = TRUE;
} else {
for (j = 0; j < c->nciphers; j++) {
if (in_commasep_string(c->list[j]->name, str, len)) {
}
}
}
- if (s->cscipher_tobe) {
- if (s->warn) {
- ssh_set_frozen(ssh, 1);
- s->dlgret = askalg(ssh->frontend,
- "client-to-server cipher",
- s->cscipher_tobe->name,
- ssh_dialog_callback, ssh);
- if (s->dlgret < 0) {
- do {
- crReturn(0);
- if (pktin) {
- bombout(("Unexpected data from server while"
- " waiting for user response"));
- crStop(0);
- }
- } while (pktin || inlen > 0);
- s->dlgret = ssh->user_response;
- }
- ssh_set_frozen(ssh, 0);
- if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
- }
- }
+ if (s->cscipher_tobe)
break;
- }
}
if (!s->cscipher_tobe) {
bombout(("Couldn't agree a client-to-server cipher (available: %s)",
}
ssh_pkt_getstring(pktin, &str, &len); /* server->client cipher */
- s->warn = 0;
for (i = 0; i < s->n_preferred_ciphers; i++) {
const struct ssh2_ciphers *c = s->preferred_ciphers[i];
if (!c) {
- s->warn = 1;
+ s->warn_sccipher = TRUE;
} else {
for (j = 0; j < c->nciphers; j++) {
if (in_commasep_string(c->list[j]->name, str, len)) {
}
}
}
- if (s->sccipher_tobe) {
- if (s->warn) {
- ssh_set_frozen(ssh, 1);
- s->dlgret = askalg(ssh->frontend,
- "server-to-client cipher",
- s->sccipher_tobe->name,
- ssh_dialog_callback, ssh);
- if (s->dlgret < 0) {
- do {
- crReturn(0);
- if (pktin) {
- bombout(("Unexpected data from server while"
- " waiting for user response"));
- crStop(0);
- }
- } while (pktin || inlen > 0);
- s->dlgret = ssh->user_response;
- }
- ssh_set_frozen(ssh, 0);
- if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
- }
- }
+ if (s->sccipher_tobe)
break;
- }
}
if (!s->sccipher_tobe) {
bombout(("Couldn't agree a server-to-client cipher (available: %s)",
}
ssh_pkt_getstring(pktin, &str, &len); /* client->server language */
ssh_pkt_getstring(pktin, &str, &len); /* server->client language */
- if (ssh2_pkt_getbool(pktin) && !s->guessok) /* first_kex_packet_follows */
+ s->ignorepkt = ssh2_pkt_getbool(pktin) && !s->guessok;
+
+ if (s->warn_kex) {
+ ssh_set_frozen(ssh, 1);
+ s->dlgret = askalg(ssh->frontend, "key-exchange algorithm",
+ ssh->kex->name,
+ ssh_dialog_callback, ssh);
+ if (s->dlgret < 0) {
+ do {
+ crReturn(0);
+ if (pktin) {
+ bombout(("Unexpected data from server while"
+ " waiting for user response"));
+ crStop(0);
+ }
+ } while (pktin || inlen > 0);
+ s->dlgret = ssh->user_response;
+ }
+ ssh_set_frozen(ssh, 0);
+ if (s->dlgret == 0) {
+ ssh->close_expected = TRUE;
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ }
+ }
+
+ if (s->warn_cscipher) {
+ ssh_set_frozen(ssh, 1);
+ s->dlgret = askalg(ssh->frontend,
+ "client-to-server cipher",
+ s->cscipher_tobe->name,
+ ssh_dialog_callback, ssh);
+ if (s->dlgret < 0) {
+ do {
+ crReturn(0);
+ if (pktin) {
+ bombout(("Unexpected data from server while"
+ " waiting for user response"));
+ crStop(0);
+ }
+ } while (pktin || inlen > 0);
+ s->dlgret = ssh->user_response;
+ }
+ ssh_set_frozen(ssh, 0);
+ if (s->dlgret == 0) {
+ ssh->close_expected = TRUE;
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ }
+ }
+
+ if (s->warn_sccipher) {
+ ssh_set_frozen(ssh, 1);
+ s->dlgret = askalg(ssh->frontend,
+ "server-to-client cipher",
+ s->sccipher_tobe->name,
+ ssh_dialog_callback, ssh);
+ if (s->dlgret < 0) {
+ do {
+ crReturn(0);
+ if (pktin) {
+ bombout(("Unexpected data from server while"
+ " waiting for user response"));
+ crStop(0);
+ }
+ } while (pktin || inlen > 0);
+ s->dlgret = ssh->user_response;
+ }
+ ssh_set_frozen(ssh, 0);
+ if (s->dlgret == 0) {
+ ssh->close_expected = TRUE;
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ }
+ }
+
+ if (s->ignorepkt) /* first_kex_packet_follows */
crWaitUntil(pktin); /* Ignore packet */
}
projects / u / mdw / putty / blobdiff