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795 lines
20 KiB
C
795 lines
20 KiB
C
/*
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* Copyright (c) 2000 Markus Friedl. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include "includes.h"
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RCSID("$OpenBSD: auth2.c,v 1.89 2002/03/19 14:27:39 markus Exp $");
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#include <openssl/evp.h>
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#include "ssh2.h"
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#include "xmalloc.h"
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#include "rsa.h"
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#include "sshpty.h"
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#include "packet.h"
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#include "buffer.h"
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#include "log.h"
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#include "servconf.h"
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#include "compat.h"
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#include "channels.h"
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#include "bufaux.h"
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#include "auth.h"
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#include "session.h"
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#include "dispatch.h"
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#include "key.h"
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#include "cipher.h"
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#include "kex.h"
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#include "pathnames.h"
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#include "uidswap.h"
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#include "auth-options.h"
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#include "hostfile.h"
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#include "canohost.h"
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#include "match.h"
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#include "monitor_wrap.h"
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/* import */
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extern ServerOptions options;
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extern u_char *session_id2;
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extern int session_id2_len;
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Authctxt *x_authctxt = NULL;
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static int one = 1;
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typedef struct Authmethod Authmethod;
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struct Authmethod {
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char *name;
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int (*userauth)(Authctxt *authctxt);
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int *enabled;
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};
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/* protocol */
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static void input_service_request(int, u_int32_t, void *);
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static void input_userauth_request(int, u_int32_t, void *);
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/* helper */
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static Authmethod *authmethod_lookup(const char *);
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static char *authmethods_get(void);
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int user_key_allowed(struct passwd *, Key *);
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int hostbased_key_allowed(struct passwd *, const char *, char *, Key *);
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/* auth */
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static void userauth_banner(void);
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static int userauth_none(Authctxt *);
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static int userauth_passwd(Authctxt *);
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static int userauth_pubkey(Authctxt *);
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static int userauth_hostbased(Authctxt *);
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static int userauth_kbdint(Authctxt *);
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Authmethod authmethods[] = {
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{"none",
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userauth_none,
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&one},
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{"publickey",
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userauth_pubkey,
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&options.pubkey_authentication},
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{"password",
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userauth_passwd,
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&options.password_authentication},
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{"keyboard-interactive",
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userauth_kbdint,
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&options.kbd_interactive_authentication},
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{"hostbased",
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userauth_hostbased,
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&options.hostbased_authentication},
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{NULL, NULL, NULL}
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};
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/*
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* loop until authctxt->success == TRUE
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*/
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Authctxt *
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do_authentication2(void)
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{
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Authctxt *authctxt = authctxt_new();
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x_authctxt = authctxt; /*XXX*/
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/* challenge-response is implemented via keyboard interactive */
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if (options.challenge_response_authentication)
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options.kbd_interactive_authentication = 1;
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if (options.pam_authentication_via_kbd_int)
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options.kbd_interactive_authentication = 1;
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if (use_privsep)
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options.pam_authentication_via_kbd_int = 0;
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dispatch_init(&dispatch_protocol_error);
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dispatch_set(SSH2_MSG_SERVICE_REQUEST, &input_service_request);
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dispatch_run(DISPATCH_BLOCK, &authctxt->success, authctxt);
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return (authctxt);
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}
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static void
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input_service_request(int type, u_int32_t seq, void *ctxt)
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{
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Authctxt *authctxt = ctxt;
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u_int len;
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int accept = 0;
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char *service = packet_get_string(&len);
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packet_check_eom();
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if (authctxt == NULL)
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fatal("input_service_request: no authctxt");
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if (strcmp(service, "ssh-userauth") == 0) {
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if (!authctxt->success) {
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accept = 1;
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/* now we can handle user-auth requests */
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dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &input_userauth_request);
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}
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}
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/* XXX all other service requests are denied */
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if (accept) {
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packet_start(SSH2_MSG_SERVICE_ACCEPT);
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packet_put_cstring(service);
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packet_send();
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packet_write_wait();
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} else {
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debug("bad service request %s", service);
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packet_disconnect("bad service request %s", service);
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}
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xfree(service);
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}
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static void
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input_userauth_request(int type, u_int32_t seq, void *ctxt)
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{
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Authctxt *authctxt = ctxt;
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Authmethod *m = NULL;
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char *user, *service, *method, *style = NULL;
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int authenticated = 0;
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if (authctxt == NULL)
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fatal("input_userauth_request: no authctxt");
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user = packet_get_string(NULL);
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service = packet_get_string(NULL);
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method = packet_get_string(NULL);
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debug("userauth-request for user %s service %s method %s", user, service, method);
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debug("attempt %d failures %d", authctxt->attempt, authctxt->failures);
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if ((style = strchr(user, ':')) != NULL)
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*style++ = 0;
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if (authctxt->attempt++ == 0) {
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/* setup auth context */
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authctxt->pw = PRIVSEP(getpwnamallow(user));
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if (authctxt->pw && strcmp(service, "ssh-connection")==0) {
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authctxt->valid = 1;
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debug2("input_userauth_request: setting up authctxt for %s", user);
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#ifdef USE_PAM
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PRIVSEP(start_pam(authctxt->pw->pw_name));
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#endif
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} else {
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log("input_userauth_request: illegal user %s", user);
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#ifdef USE_PAM
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PRIVSEP(start_pam("NOUSER"));
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#endif
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}
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setproctitle("%s%s", authctxt->pw ? user : "unknown",
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use_privsep ? " [net]" : "");
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authctxt->user = xstrdup(user);
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authctxt->service = xstrdup(service);
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authctxt->style = style ? xstrdup(style) : NULL;
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if (use_privsep)
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mm_inform_authserv(service, style);
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} else if (strcmp(user, authctxt->user) != 0 ||
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strcmp(service, authctxt->service) != 0) {
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packet_disconnect("Change of username or service not allowed: "
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"(%s,%s) -> (%s,%s)",
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authctxt->user, authctxt->service, user, service);
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}
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/* reset state */
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auth2_challenge_stop(authctxt);
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authctxt->postponed = 0;
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/* try to authenticate user */
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m = authmethod_lookup(method);
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if (m != NULL) {
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debug2("input_userauth_request: try method %s", method);
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authenticated = m->userauth(authctxt);
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}
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userauth_finish(authctxt, authenticated, method);
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xfree(service);
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xfree(user);
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xfree(method);
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}
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void
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userauth_finish(Authctxt *authctxt, int authenticated, char *method)
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{
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char *methods;
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if (!authctxt->valid && authenticated)
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fatal("INTERNAL ERROR: authenticated invalid user %s",
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authctxt->user);
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/* Special handling for root */
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if (authenticated && authctxt->pw->pw_uid == 0 &&
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!auth_root_allowed(method))
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authenticated = 0;
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#ifdef USE_PAM
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if (!use_privsep && authenticated && authctxt->user &&
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!do_pam_account(authctxt->user, NULL))
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authenticated = 0;
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#endif /* USE_PAM */
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/* Log before sending the reply */
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auth_log(authctxt, authenticated, method, " ssh2");
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if (authctxt->postponed)
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return;
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/* XXX todo: check if multiple auth methods are needed */
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if (authenticated == 1) {
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/* turn off userauth */
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dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &dispatch_protocol_ignore);
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packet_start(SSH2_MSG_USERAUTH_SUCCESS);
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packet_send();
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packet_write_wait();
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/* now we can break out */
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authctxt->success = 1;
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} else {
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if (authctxt->failures++ > AUTH_FAIL_MAX) {
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#ifdef WITH_AIXAUTHENTICATE
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loginfailed(authctxt->user,
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get_canonical_hostname(options.verify_reverse_mapping),
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"ssh");
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#endif /* WITH_AIXAUTHENTICATE */
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packet_disconnect(AUTH_FAIL_MSG, authctxt->user);
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}
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methods = authmethods_get();
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packet_start(SSH2_MSG_USERAUTH_FAILURE);
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packet_put_cstring(methods);
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packet_put_char(0); /* XXX partial success, unused */
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packet_send();
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packet_write_wait();
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xfree(methods);
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}
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}
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static void
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userauth_banner(void)
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{
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struct stat st;
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char *banner = NULL;
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off_t len, n;
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int fd;
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if (options.banner == NULL || (datafellows & SSH_BUG_BANNER))
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return;
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if ((fd = open(options.banner, O_RDONLY)) < 0)
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return;
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if (fstat(fd, &st) < 0)
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goto done;
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len = st.st_size;
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banner = xmalloc(len + 1);
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if ((n = read(fd, banner, len)) < 0)
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goto done;
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banner[n] = '\0';
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packet_start(SSH2_MSG_USERAUTH_BANNER);
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packet_put_cstring(banner);
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packet_put_cstring(""); /* language, unused */
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packet_send();
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debug("userauth_banner: sent");
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done:
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if (banner)
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xfree(banner);
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close(fd);
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return;
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}
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static int
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userauth_none(Authctxt *authctxt)
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{
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/* disable method "none", only allowed one time */
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Authmethod *m = authmethod_lookup("none");
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if (m != NULL)
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m->enabled = NULL;
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packet_check_eom();
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userauth_banner();
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if (authctxt->valid == 0)
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return(0);
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#ifdef HAVE_CYGWIN
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if (check_nt_auth(1, authctxt->pw) == 0)
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return(0);
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#endif
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return PRIVSEP(auth_password(authctxt, ""));
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}
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static int
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userauth_passwd(Authctxt *authctxt)
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{
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char *password;
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int authenticated = 0;
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int change;
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u_int len;
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change = packet_get_char();
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if (change)
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log("password change not supported");
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password = packet_get_string(&len);
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packet_check_eom();
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if (authctxt->valid &&
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#ifdef HAVE_CYGWIN
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check_nt_auth(1, authctxt->pw) &&
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#endif
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PRIVSEP(auth_password(authctxt, password)) == 1)
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authenticated = 1;
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memset(password, 0, len);
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xfree(password);
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return authenticated;
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}
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static int
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userauth_kbdint(Authctxt *authctxt)
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{
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int authenticated = 0;
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char *lang, *devs;
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lang = packet_get_string(NULL);
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devs = packet_get_string(NULL);
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packet_check_eom();
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debug("keyboard-interactive devs %s", devs);
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if (options.challenge_response_authentication)
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authenticated = auth2_challenge(authctxt, devs);
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#ifdef USE_PAM
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if (authenticated == 0 && options.pam_authentication_via_kbd_int)
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authenticated = auth2_pam(authctxt);
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#endif
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xfree(devs);
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xfree(lang);
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#ifdef HAVE_CYGWIN
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if (check_nt_auth(0, authctxt->pw) == 0)
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return(0);
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#endif
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return authenticated;
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}
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static int
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userauth_pubkey(Authctxt *authctxt)
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{
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Buffer b;
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Key *key = NULL;
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char *pkalg;
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u_char *pkblob, *sig;
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u_int alen, blen, slen;
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int have_sig, pktype;
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int authenticated = 0;
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if (!authctxt->valid) {
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debug2("userauth_pubkey: disabled because of invalid user");
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return 0;
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}
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have_sig = packet_get_char();
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if (datafellows & SSH_BUG_PKAUTH) {
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debug2("userauth_pubkey: SSH_BUG_PKAUTH");
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/* no explicit pkalg given */
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pkblob = packet_get_string(&blen);
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buffer_init(&b);
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buffer_append(&b, pkblob, blen);
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/* so we have to extract the pkalg from the pkblob */
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pkalg = buffer_get_string(&b, &alen);
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buffer_free(&b);
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} else {
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pkalg = packet_get_string(&alen);
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pkblob = packet_get_string(&blen);
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}
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pktype = key_type_from_name(pkalg);
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if (pktype == KEY_UNSPEC) {
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/* this is perfectly legal */
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log("userauth_pubkey: unsupported public key algorithm: %s",
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pkalg);
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goto done;
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}
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key = key_from_blob(pkblob, blen);
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if (key == NULL) {
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error("userauth_pubkey: cannot decode key: %s", pkalg);
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goto done;
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}
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if (key->type != pktype) {
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error("userauth_pubkey: type mismatch for decoded key "
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"(received %d, expected %d)", key->type, pktype);
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goto done;
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}
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if (have_sig) {
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sig = packet_get_string(&slen);
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packet_check_eom();
|
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buffer_init(&b);
|
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if (datafellows & SSH_OLD_SESSIONID) {
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buffer_append(&b, session_id2, session_id2_len);
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} else {
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buffer_put_string(&b, session_id2, session_id2_len);
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}
|
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/* reconstruct packet */
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buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
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buffer_put_cstring(&b, authctxt->user);
|
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buffer_put_cstring(&b,
|
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datafellows & SSH_BUG_PKSERVICE ?
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"ssh-userauth" :
|
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authctxt->service);
|
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if (datafellows & SSH_BUG_PKAUTH) {
|
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buffer_put_char(&b, have_sig);
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} else {
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buffer_put_cstring(&b, "publickey");
|
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buffer_put_char(&b, have_sig);
|
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buffer_put_cstring(&b, pkalg);
|
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}
|
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buffer_put_string(&b, pkblob, blen);
|
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#ifdef DEBUG_PK
|
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buffer_dump(&b);
|
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#endif
|
|
/* test for correct signature */
|
|
authenticated = 0;
|
|
if (PRIVSEP(user_key_allowed(authctxt->pw, key)) &&
|
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PRIVSEP(key_verify(key, sig, slen, buffer_ptr(&b),
|
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buffer_len(&b))) == 1)
|
|
authenticated = 1;
|
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buffer_clear(&b);
|
|
xfree(sig);
|
|
} else {
|
|
debug("test whether pkalg/pkblob are acceptable");
|
|
packet_check_eom();
|
|
|
|
/* XXX fake reply and always send PK_OK ? */
|
|
/*
|
|
* XXX this allows testing whether a user is allowed
|
|
* to login: if you happen to have a valid pubkey this
|
|
* message is sent. the message is NEVER sent at all
|
|
* if a user is not allowed to login. is this an
|
|
* issue? -markus
|
|
*/
|
|
if (PRIVSEP(user_key_allowed(authctxt->pw, key))) {
|
|
packet_start(SSH2_MSG_USERAUTH_PK_OK);
|
|
packet_put_string(pkalg, alen);
|
|
packet_put_string(pkblob, blen);
|
|
packet_send();
|
|
packet_write_wait();
|
|
authctxt->postponed = 1;
|
|
}
|
|
}
|
|
if (authenticated != 1)
|
|
auth_clear_options();
|
|
done:
|
|
debug2("userauth_pubkey: authenticated %d pkalg %s", authenticated, pkalg);
|
|
if (key != NULL)
|
|
key_free(key);
|
|
xfree(pkalg);
|
|
xfree(pkblob);
|
|
#ifdef HAVE_CYGWIN
|
|
if (check_nt_auth(0, authctxt->pw) == 0)
|
|
return(0);
|
|
#endif
|
|
return authenticated;
|
|
}
|
|
|
|
static int
|
|
userauth_hostbased(Authctxt *authctxt)
|
|
{
|
|
Buffer b;
|
|
Key *key = NULL;
|
|
char *pkalg, *cuser, *chost, *service;
|
|
u_char *pkblob, *sig;
|
|
u_int alen, blen, slen;
|
|
int pktype;
|
|
int authenticated = 0;
|
|
|
|
if (!authctxt->valid) {
|
|
debug2("userauth_hostbased: disabled because of invalid user");
|
|
return 0;
|
|
}
|
|
pkalg = packet_get_string(&alen);
|
|
pkblob = packet_get_string(&blen);
|
|
chost = packet_get_string(NULL);
|
|
cuser = packet_get_string(NULL);
|
|
sig = packet_get_string(&slen);
|
|
|
|
debug("userauth_hostbased: cuser %s chost %s pkalg %s slen %d",
|
|
cuser, chost, pkalg, slen);
|
|
#ifdef DEBUG_PK
|
|
debug("signature:");
|
|
buffer_init(&b);
|
|
buffer_append(&b, sig, slen);
|
|
buffer_dump(&b);
|
|
buffer_free(&b);
|
|
#endif
|
|
pktype = key_type_from_name(pkalg);
|
|
if (pktype == KEY_UNSPEC) {
|
|
/* this is perfectly legal */
|
|
log("userauth_hostbased: unsupported "
|
|
"public key algorithm: %s", pkalg);
|
|
goto done;
|
|
}
|
|
key = key_from_blob(pkblob, blen);
|
|
if (key == NULL) {
|
|
error("userauth_hostbased: cannot decode key: %s", pkalg);
|
|
goto done;
|
|
}
|
|
if (key->type != pktype) {
|
|
error("userauth_hostbased: type mismatch for decoded key "
|
|
"(received %d, expected %d)", key->type, pktype);
|
|
goto done;
|
|
}
|
|
service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
|
|
authctxt->service;
|
|
buffer_init(&b);
|
|
buffer_put_string(&b, session_id2, session_id2_len);
|
|
/* reconstruct packet */
|
|
buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
|
|
buffer_put_cstring(&b, authctxt->user);
|
|
buffer_put_cstring(&b, service);
|
|
buffer_put_cstring(&b, "hostbased");
|
|
buffer_put_string(&b, pkalg, alen);
|
|
buffer_put_string(&b, pkblob, blen);
|
|
buffer_put_cstring(&b, chost);
|
|
buffer_put_cstring(&b, cuser);
|
|
#ifdef DEBUG_PK
|
|
buffer_dump(&b);
|
|
#endif
|
|
/* test for allowed key and correct signature */
|
|
authenticated = 0;
|
|
if (PRIVSEP(hostbased_key_allowed(authctxt->pw, cuser, chost, key)) &&
|
|
PRIVSEP(key_verify(key, sig, slen, buffer_ptr(&b),
|
|
buffer_len(&b))) == 1)
|
|
authenticated = 1;
|
|
|
|
buffer_clear(&b);
|
|
done:
|
|
debug2("userauth_hostbased: authenticated %d", authenticated);
|
|
if (key != NULL)
|
|
key_free(key);
|
|
xfree(pkalg);
|
|
xfree(pkblob);
|
|
xfree(cuser);
|
|
xfree(chost);
|
|
xfree(sig);
|
|
return authenticated;
|
|
}
|
|
|
|
/* get current user */
|
|
|
|
struct passwd*
|
|
auth_get_user(void)
|
|
{
|
|
return (x_authctxt != NULL && x_authctxt->valid) ? x_authctxt->pw : NULL;
|
|
}
|
|
|
|
#define DELIM ","
|
|
|
|
static char *
|
|
authmethods_get(void)
|
|
{
|
|
Authmethod *method = NULL;
|
|
Buffer b;
|
|
char *list;
|
|
|
|
buffer_init(&b);
|
|
for (method = authmethods; method->name != NULL; method++) {
|
|
if (strcmp(method->name, "none") == 0)
|
|
continue;
|
|
if (method->enabled != NULL && *(method->enabled) != 0) {
|
|
if (buffer_len(&b) > 0)
|
|
buffer_append(&b, ",", 1);
|
|
buffer_append(&b, method->name, strlen(method->name));
|
|
}
|
|
}
|
|
buffer_append(&b, "\0", 1);
|
|
list = xstrdup(buffer_ptr(&b));
|
|
buffer_free(&b);
|
|
return list;
|
|
}
|
|
|
|
static Authmethod *
|
|
authmethod_lookup(const char *name)
|
|
{
|
|
Authmethod *method = NULL;
|
|
if (name != NULL)
|
|
for (method = authmethods; method->name != NULL; method++)
|
|
if (method->enabled != NULL &&
|
|
*(method->enabled) != 0 &&
|
|
strcmp(name, method->name) == 0)
|
|
return method;
|
|
debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
|
|
return NULL;
|
|
}
|
|
|
|
/* return 1 if user allows given key */
|
|
static int
|
|
user_key_allowed2(struct passwd *pw, Key *key, char *file)
|
|
{
|
|
char line[8192];
|
|
int found_key = 0;
|
|
FILE *f;
|
|
u_long linenum = 0;
|
|
struct stat st;
|
|
Key *found;
|
|
char *fp;
|
|
|
|
if (pw == NULL)
|
|
return 0;
|
|
|
|
/* Temporarily use the user's uid. */
|
|
temporarily_use_uid(pw);
|
|
|
|
debug("trying public key file %s", file);
|
|
|
|
/* Fail quietly if file does not exist */
|
|
if (stat(file, &st) < 0) {
|
|
/* Restore the privileged uid. */
|
|
restore_uid();
|
|
return 0;
|
|
}
|
|
/* Open the file containing the authorized keys. */
|
|
f = fopen(file, "r");
|
|
if (!f) {
|
|
/* Restore the privileged uid. */
|
|
restore_uid();
|
|
return 0;
|
|
}
|
|
if (options.strict_modes &&
|
|
secure_filename(f, file, pw, line, sizeof(line)) != 0) {
|
|
fclose(f);
|
|
log("Authentication refused: %s", line);
|
|
restore_uid();
|
|
return 0;
|
|
}
|
|
|
|
found_key = 0;
|
|
found = key_new(key->type);
|
|
|
|
while (fgets(line, sizeof(line), f)) {
|
|
char *cp, *options = NULL;
|
|
linenum++;
|
|
/* Skip leading whitespace, empty and comment lines. */
|
|
for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
|
|
;
|
|
if (!*cp || *cp == '\n' || *cp == '#')
|
|
continue;
|
|
|
|
if (key_read(found, &cp) != 1) {
|
|
/* no key? check if there are options for this key */
|
|
int quoted = 0;
|
|
debug2("user_key_allowed: check options: '%s'", cp);
|
|
options = cp;
|
|
for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
|
|
if (*cp == '\\' && cp[1] == '"')
|
|
cp++; /* Skip both */
|
|
else if (*cp == '"')
|
|
quoted = !quoted;
|
|
}
|
|
/* Skip remaining whitespace. */
|
|
for (; *cp == ' ' || *cp == '\t'; cp++)
|
|
;
|
|
if (key_read(found, &cp) != 1) {
|
|
debug2("user_key_allowed: advance: '%s'", cp);
|
|
/* still no key? advance to next line*/
|
|
continue;
|
|
}
|
|
}
|
|
if (key_equal(found, key) &&
|
|
auth_parse_options(pw, options, file, linenum) == 1) {
|
|
found_key = 1;
|
|
debug("matching key found: file %s, line %lu",
|
|
file, linenum);
|
|
fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
|
|
verbose("Found matching %s key: %s",
|
|
key_type(found), fp);
|
|
xfree(fp);
|
|
break;
|
|
}
|
|
}
|
|
restore_uid();
|
|
fclose(f);
|
|
key_free(found);
|
|
if (!found_key)
|
|
debug2("key not found");
|
|
return found_key;
|
|
}
|
|
|
|
/* check whether given key is in .ssh/authorized_keys* */
|
|
int
|
|
user_key_allowed(struct passwd *pw, Key *key)
|
|
{
|
|
int success;
|
|
char *file;
|
|
|
|
file = authorized_keys_file(pw);
|
|
success = user_key_allowed2(pw, key, file);
|
|
xfree(file);
|
|
if (success)
|
|
return success;
|
|
|
|
/* try suffix "2" for backward compat, too */
|
|
file = authorized_keys_file2(pw);
|
|
success = user_key_allowed2(pw, key, file);
|
|
xfree(file);
|
|
return success;
|
|
}
|
|
|
|
/* return 1 if given hostkey is allowed */
|
|
int
|
|
hostbased_key_allowed(struct passwd *pw, const char *cuser, char *chost,
|
|
Key *key)
|
|
{
|
|
const char *resolvedname, *ipaddr, *lookup;
|
|
HostStatus host_status;
|
|
int len;
|
|
|
|
resolvedname = get_canonical_hostname(options.verify_reverse_mapping);
|
|
ipaddr = get_remote_ipaddr();
|
|
|
|
debug2("userauth_hostbased: chost %s resolvedname %s ipaddr %s",
|
|
chost, resolvedname, ipaddr);
|
|
|
|
if (options.hostbased_uses_name_from_packet_only) {
|
|
if (auth_rhosts2(pw, cuser, chost, chost) == 0)
|
|
return 0;
|
|
lookup = chost;
|
|
} else {
|
|
if (((len = strlen(chost)) > 0) && chost[len - 1] == '.') {
|
|
debug2("stripping trailing dot from chost %s", chost);
|
|
chost[len - 1] = '\0';
|
|
}
|
|
if (strcasecmp(resolvedname, chost) != 0)
|
|
log("userauth_hostbased mismatch: "
|
|
"client sends %s, but we resolve %s to %s",
|
|
chost, ipaddr, resolvedname);
|
|
if (auth_rhosts2(pw, cuser, resolvedname, ipaddr) == 0)
|
|
return 0;
|
|
lookup = resolvedname;
|
|
}
|
|
debug2("userauth_hostbased: access allowed by auth_rhosts2");
|
|
|
|
host_status = check_key_in_hostfiles(pw, key, lookup,
|
|
_PATH_SSH_SYSTEM_HOSTFILE,
|
|
options.ignore_user_known_hosts ? NULL : _PATH_SSH_USER_HOSTFILE);
|
|
|
|
/* backward compat if no key has been found. */
|
|
if (host_status == HOST_NEW)
|
|
host_status = check_key_in_hostfiles(pw, key, lookup,
|
|
_PATH_SSH_SYSTEM_HOSTFILE2,
|
|
options.ignore_user_known_hosts ? NULL :
|
|
_PATH_SSH_USER_HOSTFILE2);
|
|
|
|
return (host_status == HOST_OK);
|
|
}
|