*/
#include "includes.h"
-RCSID("$OpenBSD: auth1.c,v 1.41 2002/06/19 00:27:55 deraadt Exp $");
+RCSID("$OpenBSD: auth1.c,v 1.59 2004/07/28 09:40:29 markus Exp $");
#include "xmalloc.h"
#include "rsa.h"
#include "ssh1.h"
#include "packet.h"
#include "buffer.h"
-#include "mpaux.h"
#include "log.h"
#include "servconf.h"
#include "compat.h"
#include "session.h"
#include "uidswap.h"
#include "monitor_wrap.h"
+#include "buffer.h"
/* import */
extern ServerOptions options;
+extern Buffer loginmsg;
/*
* convert ssh auth msg type into description
case SSH_CMSG_AUTH_TIS:
case SSH_CMSG_AUTH_TIS_RESPONSE:
return "challenge-response";
-#if defined(KRB4) || defined(KRB5)
- case SSH_CMSG_AUTH_KERBEROS:
- return "kerberos";
-#endif
}
snprintf(buf, sizeof buf, "bad-auth-msg-%d", type);
return buf;
char info[1024];
u_int dlen;
u_int ulen;
- int type = 0;
- struct passwd *pw = authctxt->pw;
+ int prev, type = 0;
debug("Attempting authentication for %s%.100s.",
- authctxt->valid ? "" : "illegal user ", authctxt->user);
+ authctxt->valid ? "" : "invalid user ", authctxt->user);
/* If the user has no password, accept authentication immediately. */
if (options.password_authentication &&
-#if defined(KRB4) || defined(KRB5)
+#ifdef KRB5
(!options.kerberos_authentication || options.kerberos_or_local_passwd) &&
#endif
PRIVSEP(auth_password(authctxt, ""))) {
- auth_log(authctxt, 1, "without authentication", "");
- return;
+#ifdef USE_PAM
+ if (options.use_pam && (PRIVSEP(do_pam_account())))
+#endif
+ {
+ auth_log(authctxt, 1, "without authentication", "");
+ return;
+ }
}
/* Indicate that authentication is needed. */
info[0] = '\0';
/* Get a packet from the client. */
+ prev = type;
type = packet_read();
+ /*
+ * If we started challenge-response authentication but the
+ * next packet is not a response to our challenge, release
+ * the resources allocated by get_challenge() (which would
+ * normally have been released by verify_response() had we
+ * received such a response)
+ */
+ if (prev == SSH_CMSG_AUTH_TIS &&
+ type != SSH_CMSG_AUTH_TIS_RESPONSE)
+ abandon_challenge_response(authctxt);
+
/* Process the packet. */
switch (type) {
-
-#if defined(KRB4) || defined(KRB5)
- case SSH_CMSG_AUTH_KERBEROS:
- if (!options.kerberos_authentication) {
- verbose("Kerberos authentication disabled.");
- } else {
- char *kdata = packet_get_string(&dlen);
- packet_check_eom();
-
- if (kdata[0] == 4) { /* KRB_PROT_VERSION */
-#ifdef KRB4
- KTEXT_ST tkt;
-
- tkt.length = dlen;
- if (tkt.length < MAX_KTXT_LEN)
- memcpy(tkt.dat, kdata, tkt.length);
-
- if (auth_krb4(authctxt, &tkt, &client_user)) {
- authenticated = 1;
- snprintf(info, sizeof(info),
- " tktuser %.100s",
- client_user);
- }
-#endif /* KRB4 */
- } else {
-#ifdef KRB5
- krb5_data tkt;
- tkt.length = dlen;
- tkt.data = kdata;
-
- if (auth_krb5(authctxt, &tkt, &client_user)) {
- authenticated = 1;
- snprintf(info, sizeof(info),
- " tktuser %.100s",
- client_user);
- }
-#endif /* KRB5 */
- }
- xfree(kdata);
- }
- break;
-#endif /* KRB4 || KRB5 */
-
-#if defined(AFS) || defined(KRB5)
- /* XXX - punt on backward compatibility here. */
- case SSH_CMSG_HAVE_KERBEROS_TGT:
- packet_send_debug("Kerberos TGT passing disabled before authentication.");
- break;
-#ifdef AFS
- case SSH_CMSG_HAVE_AFS_TOKEN:
- packet_send_debug("AFS token passing disabled before authentication.");
- break;
-#endif /* AFS */
-#endif /* AFS || KRB5 */
-
- case SSH_CMSG_AUTH_RHOSTS:
- if (!options.rhosts_authentication) {
- verbose("Rhosts authentication disabled.");
- break;
- }
- /*
- * Get client user name. Note that we just have to
- * trust the client; this is one reason why rhosts
- * authentication is insecure. (Another is
- * IP-spoofing on a local network.)
- */
- client_user = packet_get_string(&ulen);
- packet_check_eom();
-
- /* Try to authenticate using /etc/hosts.equiv and .rhosts. */
- authenticated = auth_rhosts(pw, client_user);
-
- snprintf(info, sizeof info, " ruser %.100s", client_user);
- break;
-
case SSH_CMSG_AUTH_RHOSTS_RSA:
if (!options.rhosts_rsa_authentication) {
verbose("Rhosts with RSA authentication disabled.");
BN_num_bits(client_host_key->rsa->n), bits);
packet_check_eom();
- authenticated = auth_rhosts_rsa(pw, client_user,
+ authenticated = auth_rhosts_rsa(authctxt, client_user,
client_host_key);
key_free(client_host_key);
fatal("do_authloop: BN_new failed");
packet_get_bignum(n);
packet_check_eom();
- authenticated = auth_rsa(pw, n);
+ authenticated = auth_rsa(authctxt, n);
BN_clear_free(n);
break;
debug("rcvd SSH_CMSG_AUTH_TIS_RESPONSE");
if (options.challenge_response_authentication == 1) {
char *response = packet_get_string(&dlen);
- debug("got response '%s'", response);
packet_check_eom();
authenticated = verify_response(authctxt, response);
memset(response, 'r', dlen);
* Any unknown messages will be ignored (and failure
* returned) during authentication.
*/
- log("Unknown message during authentication: type %d", type);
+ logit("Unknown message during authentication: type %d", type);
break;
}
#ifdef BSD_AUTH
fatal("INTERNAL ERROR: authenticated invalid user %s",
authctxt->user);
+#ifdef _UNICOS
+ if (authenticated && cray_access_denied(authctxt->user)) {
+ authenticated = 0;
+ fatal("Access denied for user %s.",authctxt->user);
+ }
+#endif /* _UNICOS */
+
#ifdef HAVE_CYGWIN
if (authenticated &&
- !check_nt_auth(type == SSH_CMSG_AUTH_PASSWORD, pw)) {
+ !check_nt_auth(type == SSH_CMSG_AUTH_PASSWORD,
+ authctxt->pw)) {
packet_disconnect("Authentication rejected for uid %d.",
- pw == NULL ? -1 : pw->pw_uid);
+ authctxt->pw == NULL ? -1 : authctxt->pw->pw_uid);
authenticated = 0;
}
#else
/* Special handling for root */
if (authenticated && authctxt->pw->pw_uid == 0 &&
- !auth_root_allowed(get_authname(type)))
+ !auth_root_allowed(get_authname(type))) {
authenticated = 0;
+# ifdef SSH_AUDIT_EVENTS
+ PRIVSEP(audit_event(SSH_LOGIN_ROOT_DENIED));
+# endif
+ }
#endif
+
#ifdef USE_PAM
- if (!use_privsep && authenticated &&
- !do_pam_account(pw->pw_name, client_user))
- authenticated = 0;
+ if (options.use_pam && authenticated &&
+ !PRIVSEP(do_pam_account())) {
+ char *msg;
+ size_t len;
+
+ error("Access denied for user %s by PAM account "
+ "configuration", authctxt->user);
+ len = buffer_len(&loginmsg);
+ buffer_append(&loginmsg, "\0", 1);
+ msg = buffer_ptr(&loginmsg);
+ /* strip trailing newlines */
+ if (len > 0)
+ while (len > 0 && msg[--len] == '\n')
+ msg[len] = '\0';
+ else
+ msg = "Access denied.";
+ packet_disconnect(msg);
+ }
#endif
/* Log before sending the reply */
if (authenticated)
return;
- if (authctxt->failures++ > AUTH_FAIL_MAX) {
-#ifdef WITH_AIXAUTHENTICATE
- loginfailed(authctxt->user,
- get_canonical_hostname(options.verify_reverse_mapping),
- "ssh");
-#endif /* WITH_AIXAUTHENTICATE */
+ if (authctxt->failures++ > options.max_authtries) {
+#ifdef SSH_AUDIT_EVENTS
+ PRIVSEP(audit_event(SSH_LOGIN_EXCEED_MAXTRIES));
+#endif
packet_disconnect(AUTH_FAIL_MSG, authctxt->user);
}
* Performs authentication of an incoming connection. Session key has already
* been exchanged and encryption is enabled.
*/
-Authctxt *
-do_authentication(void)
+void
+do_authentication(Authctxt *authctxt)
{
- Authctxt *authctxt;
u_int ulen;
char *user, *style = NULL;
if ((style = strchr(user, ':')) != NULL)
*style++ = '\0';
-#ifdef KRB5
- /* XXX - SSH.com Kerberos v5 braindeath. */
- if ((datafellows & SSH_BUG_K5USER) &&
- options.kerberos_authentication) {
- char *p;
- if ((p = strchr(user, '@')) != NULL)
- *p = '\0';
- }
-#endif
-
- 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);
+ else {
+ debug("do_authentication: invalid user %s", user);
+ authctxt->pw = fakepw();
+ }
- setproctitle("%s%s", authctxt->pw ? user : "unknown",
+ setproctitle("%s%s", authctxt->valid ? user : "unknown",
use_privsep ? " [net]" : "");
#ifdef USE_PAM
- PRIVSEP(start_pam(authctxt->pw == NULL ? "NOUSER" : user));
+ if (options.use_pam)
+ PRIVSEP(start_pam(authctxt));
#endif
/*
packet_start(SSH_SMSG_SUCCESS);
packet_send();
packet_write_wait();
-
- return (authctxt);
}