struct ssh_channel *mainchan; /* primary session channel */
int exitcode;
int close_expected;
+ int clean_exit;
tree234 *rportfwds, *portfwds;
*/
int fallback_cmd;
+ bufchain banner; /* accumulates banners during do_ssh2_authconn */
/*
* Used for username and password input.
*/
Ssh ssh = (Ssh) plug;
int need_notify = ssh_do_close(ssh, FALSE);
- if (!error_msg && !ssh->close_expected) {
- error_msg = "Server unexpectedly closed network connection";
+ if (!error_msg) {
+ if (!ssh->close_expected)
+ error_msg = "Server unexpectedly closed network connection";
+ else
+ error_msg = "Server closed network connection";
}
if (need_notify)
notify_remote_exit(ssh->frontend);
- if (error_msg) {
- /* A socket error has occurred. */
+ if (error_msg)
logevent(error_msg);
+ if (!ssh->close_expected || !ssh->clean_exit)
connection_fatal(ssh->frontend, "%s", error_msg);
- } else {
- logevent("Server closed network connection");
- }
return 0;
}
}
/*
+ * Client-initiated disconnection. Send a DISCONNECT if `wire_reason'
+ * non-NULL, otherwise just close the connection. `client_reason' == NULL
+ * => log `wire_reason'.
+ */
+static void ssh_disconnect(Ssh ssh, char *client_reason, char *wire_reason,
+ int code, int clean_exit)
+{
+ char *error;
+ if (!client_reason)
+ client_reason = wire_reason;
+ if (client_reason)
+ error = dupprintf("Disconnected: %s", client_reason);
+ else
+ error = dupstr("Disconnected");
+ if (wire_reason) {
+ if (ssh->version == 1) {
+ send_packet(ssh, SSH1_MSG_DISCONNECT, PKT_STR, wire_reason,
+ PKT_END);
+ } else if (ssh->version == 2) {
+ struct Packet *pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
+ ssh2_pkt_adduint32(pktout, code);
+ ssh2_pkt_addstring(pktout, wire_reason);
+ ssh2_pkt_addstring(pktout, "en"); /* language tag */
+ ssh2_pkt_send_noqueue(ssh, pktout);
+ }
+ }
+ ssh->close_expected = TRUE;
+ ssh->clean_exit = clean_exit;
+ ssh_closing((Plug)ssh, error, 0, 0);
+ sfree(error);
+}
+
+/*
* Handle the key exchange and user authentication phases.
*/
static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
ssh_set_frozen(ssh, 0);
if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "User aborted at host key verification",
+ NULL, 0, TRUE);
crStop(0);
}
}
}
ssh_set_frozen(ssh, 0);
if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "User aborted at cipher warning", NULL,
+ 0, TRUE);
crStop(0);
}
}
* get_line failed to get a username.
* Terminate.
*/
- logevent("No username provided. Abandoning session.");
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "No username provided", NULL, 0, TRUE);
crStop(1);
}
} else {
* because one was supplied on the command line
* which has already failed to work). Terminate.
*/
- send_packet(ssh, SSH1_MSG_DISCONNECT,
- PKT_STR, "No more passwords available to try",
- PKT_END);
- logevent("Unable to authenticate");
- connection_fatal(ssh->frontend, "Unable to authenticate");
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, NULL, "Unable to authenticate", 0, FALSE);
crStop(1);
}
} else {
* encrypted packet, we close the session once
* we've sent EXIT_CONFIRMATION.
*/
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, NULL, NULL, 0, TRUE);
}
/* Helper function to deal with sending tty modes for REQUEST_PTY */
ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
data, sizeof(data), ssh->cfg.x11_auth);
x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
+ /*
+ * Note that while we blank the X authentication data here, we don't
+ * take any special action to blank the start of an X11 channel,
+ * so using MIT-MAGIC-COOKIE-1 and actually opening an X connection
+ * without having session blanking enabled is likely to leak your
+ * cookie into the log.
+ */
if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
- PKT_STR, proto, PKT_STR, data,
+ PKT_STR, proto,
+ PKTT_PASSWORD, PKT_STR, data, PKTT_OTHER,
PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
PKT_END);
} else {
send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
- PKT_STR, proto, PKT_STR, data, PKT_END);
+ PKT_STR, proto,
+ PKTT_PASSWORD, PKT_STR, data, PKTT_OTHER, PKT_END);
}
do {
crReturnV;
}
ssh_set_frozen(ssh, 0);
if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "User aborted at kex warning", NULL,
+ 0, TRUE);
crStop(0);
}
}
}
ssh_set_frozen(ssh, 0);
if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "User aborted at cipher warning", NULL,
+ 0, TRUE);
crStop(0);
}
}
}
ssh_set_frozen(ssh, 0);
if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "User aborted at cipher warning", NULL,
+ 0, TRUE);
crStop(0);
}
}
}
ssh_set_frozen(ssh, 0);
if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "User aborted at host key verification", NULL,
+ 0, TRUE);
crStop(0);
}
if (!s->got_session_id) { /* don't bother logging this in rekeys */
* not running in -N mode.)
*/
if (!ssh->cfg.ssh_no_shell && count234(ssh->channels) == 0) {
- logevent("All channels closed. Disconnecting");
-#if 0
/*
* We used to send SSH_MSG_DISCONNECT here,
* because I'd believed that _every_ conforming
* this is more polite than sending a
* DISCONNECT. So now we don't.
*/
- s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(s->pktout, "All open channels closed");
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, s->pktout);
-#endif
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "All channels closed", NULL, 0, TRUE);
}
}
*/
c = find234(ssh->channels, &localid, ssh_channelfind);
if (!c) {
- char buf[80];
- sprintf(buf, "Received channel request for nonexistent"
- " channel %d", localid);
- logevent(buf);
- pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(pktout, SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(pktout, buf);
- ssh2_pkt_addstring(pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, pktout);
- connection_fatal(ssh->frontend, "%s", buf);
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ char *buf = dupprintf("Received channel request for nonexistent"
+ " channel %d", localid);
+ ssh_disconnect(ssh, NULL, buf, SSH2_DISCONNECT_PROTOCOL_ERROR, FALSE);
+ sfree(buf);
return;
}
}
}
+/*
+ * Buffer banner messages for later display at some convenient point.
+ */
+static void ssh2_msg_userauth_banner(Ssh ssh, struct Packet *pktin)
+{
+ /* Arbitrary limit to prevent unbounded inflation of buffer */
+ if (bufchain_size(&ssh->banner) <= 131072) {
+ char *banner = NULL;
+ int size = 0;
+ ssh_pkt_getstring(pktin, &banner, &size);
+ if (banner)
+ bufchain_add(&ssh->banner, banner, size);
+ }
+}
+
/* Helper function to deal with sending tty modes for "pty-req" */
static void ssh2_send_ttymode(void *data, char *mode, char *val)
{
AUTH_TYPE_KEYBOARD_INTERACTIVE,
AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
} type;
+ int done_service_req;
int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
int tried_pubkey_config, tried_agent;
int kbd_inter_running, kbd_inter_refused;
crBegin(ssh->do_ssh2_authconn_crstate);
- /*
- * Request userauth protocol, and await a response to it.
- */
- s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
- ssh2_pkt_addstring(s->pktout, "ssh-userauth");
- ssh2_pkt_send(ssh, s->pktout);
- crWaitUntilV(pktin);
- if (pktin->type != SSH2_MSG_SERVICE_ACCEPT) {
- bombout(("Server refused user authentication protocol"));
- crStopV;
+ s->done_service_req = FALSE;
+ s->we_are_in = FALSE;
+ if (!ssh->cfg.ssh_no_userauth) {
+ /*
+ * Request userauth protocol, and await a response to it.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
+ ssh2_pkt_addstring(s->pktout, "ssh-userauth");
+ ssh2_pkt_send(ssh, s->pktout);
+ crWaitUntilV(pktin);
+ if (pktin->type == SSH2_MSG_SERVICE_ACCEPT)
+ s->done_service_req = TRUE;
+ }
+ if (!s->done_service_req) {
+ /*
+ * Request connection protocol directly, without authentication.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");
+ ssh2_pkt_send(ssh, s->pktout);
+ crWaitUntilV(pktin);
+ if (pktin->type == SSH2_MSG_SERVICE_ACCEPT) {
+ s->we_are_in = TRUE; /* no auth required */
+ } else {
+ bombout(("Server refused service request"));
+ crStopV;
+ }
}
/*
*/
s->username[0] = '\0';
s->got_username = FALSE;
- do {
+ bufchain_init(&ssh->banner);
+ ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] =
+ ssh2_msg_userauth_banner;
+ while (!s->we_are_in) {
/*
* Get a username.
*/
* get_line failed to get a username.
* Terminate.
*/
- logevent("No username provided. Abandoning session.");
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "No username provided", NULL, 0, TRUE);
crStopV;
}
} else {
*/
if (!s->gotit)
crWaitUntilV(pktin);
- while (pktin->type == SSH2_MSG_USERAUTH_BANNER) {
- char *banner;
- int size;
+ /*
+ * Now is a convenient point to spew any banner material
+ * that we've accumulated. (This should ensure that when
+ * we exit the auth loop, we haven't any left to deal
+ * with.)
+ */
+ {
+ int size = bufchain_size(&ssh->banner);
/*
* Don't show the banner if we're operating in
* non-verbose non-interactive mode. (It's probably
* the banner will screw up processing on the
* output of (say) plink.)
*/
- if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
- ssh_pkt_getstring(pktin, &banner, &size);
- if (banner)
- c_write_untrusted(ssh, banner, size);
+ if (size && (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE))) {
+ char *banner = snewn(size, char);
+ bufchain_fetch(&ssh->banner, banner, size);
+ c_write_untrusted(ssh, banner, size);
+ sfree(banner);
}
- crWaitUntilV(pktin);
+ bufchain_clear(&ssh->banner);
}
if (pktin->type == SSH2_MSG_USERAUTH_SUCCESS) {
logevent("Access granted");
* command line which has already failed to
* work). Terminate.
*/
- s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(s->pktout,SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(s->pktout, "No more passwords available"
- " to try");
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, s->pktout);
- logevent("Unable to authenticate");
- connection_fatal(ssh->frontend,
- "Unable to authenticate");
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, NULL, "Unable to authenticate",
+ SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER,
+ FALSE);
crStopV;
}
} else {
}
s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
} else {
- c_write_str(ssh, "No supported authentication methods"
- " left to try!\r\n");
- logevent("No supported authentications offered."
- " Disconnecting");
- s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(s->pktout, "No supported authentication"
- " methods available");
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, s->pktout);
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, NULL,
+ "No supported authentication methods available",
+ SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE,
+ FALSE);
crStopV;
}
}
- } while (!s->we_are_in);
+ }
+ ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] = NULL;
/*
- * Now we're authenticated for the connection protocol. The
- * connection protocol will automatically have started at this
- * point; there's no need to send SERVICE_REQUEST.
+ * Now the connection protocol has started, one way or another.
*/
ssh->channels = newtree234(ssh_channelcmp);
ssh2_pkt_addbool(s->pktout, 1); /* want reply */
ssh2_pkt_addbool(s->pktout, 0); /* many connections */
ssh2_pkt_addstring(s->pktout, proto);
+ /*
+ * Note that while we blank the X authentication data here, we don't
+ * take any special action to blank the start of an X11 channel,
+ * so using MIT-MAGIC-COOKIE-1 and actually opening an X connection
+ * without having session blanking enabled is likely to leak your
+ * cookie into the log.
+ */
dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
ssh2_pkt_addstring(s->pktout, data);
end_log_omission(ssh, s->pktout);
ssh->hostkey = NULL;
ssh->exitcode = -1;
ssh->close_expected = FALSE;
+ ssh->clean_exit = FALSE;
ssh->state = SSH_STATE_PREPACKET;
ssh->size_needed = FALSE;
ssh->eof_needed = FALSE;
unsigned long old_max_data_size;
pinger_reconfig(ssh->pinger, &ssh->cfg, cfg);
- ssh_setup_portfwd(ssh, cfg);
+ if (ssh->portfwds)
+ ssh_setup_portfwd(ssh, cfg);
if (ssh->cfg.ssh_rekey_time != cfg->ssh_rekey_time &&
cfg->ssh_rekey_time != 0) {
}
/*
- * Called to send data down the Telnet connection.
+ * Called to send data down the SSH connection.
*/
static int ssh_send(void *handle, char *buf, int len)
{
}
/*
- * Send Telnet special codes. TS_EOF is useful for `plink', so you
+ * Send special codes. TS_EOF is useful for `plink', so you
* can send an EOF and collect resulting output (e.g. `plink
* hostname sort').
*/
projects / u / mdw / putty / blobdiff