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			873 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			873 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* $OpenBSD: auth.c,v 1.113 2015/08/21 03:42:19 djm Exp $ */
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/*
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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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#include <sys/types.h>
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#include <sys/stat.h>
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#include <netinet/in.h>
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#include <errno.h>
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#include <fcntl.h>
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#ifdef HAVE_PATHS_H
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# include <paths.h>
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#endif
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#include <pwd.h>
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#ifdef HAVE_LOGIN_H
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#include <login.h>
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#endif
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#ifdef USE_SHADOW
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#include <shadow.h>
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#endif
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#ifdef HAVE_LIBGEN_H
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#include <libgen.h>
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#endif
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#include <stdarg.h>
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#include <stdio.h>
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#include <string.h>
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#include <unistd.h>
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#include <limits.h>
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#include "xmalloc.h"
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#include "match.h"
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#include "groupaccess.h"
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#include "log.h"
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#include "buffer.h"
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#include "misc.h"
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#include "servconf.h"
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#include "key.h"
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#include "hostfile.h"
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#include "auth.h"
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#include "auth-options.h"
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#include "canohost.h"
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#include "uidswap.h"
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#include "packet.h"
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#include "loginrec.h"
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#ifdef GSSAPI
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#include "ssh-gss.h"
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#endif
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#include "authfile.h"
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#include "monitor_wrap.h"
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#include "authfile.h"
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#include "ssherr.h"
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#include "compat.h"
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/* import */
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extern ServerOptions options;
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extern int use_privsep;
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extern Buffer loginmsg;
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extern struct passwd *privsep_pw;
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/* Debugging messages */
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Buffer auth_debug;
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int auth_debug_init;
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/*
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 * Check if the user is allowed to log in via ssh. If user is listed
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 * in DenyUsers or one of user's groups is listed in DenyGroups, false
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 * will be returned. If AllowUsers isn't empty and user isn't listed
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 * there, or if AllowGroups isn't empty and one of user's groups isn't
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 * listed there, false will be returned.
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 * If the user's shell is not executable, false will be returned.
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 * Otherwise true is returned.
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 */
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int
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allowed_user(struct passwd * pw)
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{
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	struct stat st;
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	const char *hostname = NULL, *ipaddr = NULL, *passwd = NULL;
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	u_int i;
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#ifdef USE_SHADOW
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	struct spwd *spw = NULL;
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#endif
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	/* Shouldn't be called if pw is NULL, but better safe than sorry... */
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	if (!pw || !pw->pw_name)
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		return 0;
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#ifdef USE_SHADOW
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	if (!options.use_pam)
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		spw = getspnam(pw->pw_name);
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#ifdef HAS_SHADOW_EXPIRE
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	if (!options.use_pam && spw != NULL && auth_shadow_acctexpired(spw))
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		return 0;
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#endif /* HAS_SHADOW_EXPIRE */
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#endif /* USE_SHADOW */
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	/* grab passwd field for locked account check */
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	passwd = pw->pw_passwd;
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#ifdef USE_SHADOW
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	if (spw != NULL)
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#ifdef USE_LIBIAF
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		passwd = get_iaf_password(pw);
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#else
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		passwd = spw->sp_pwdp;
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#endif /* USE_LIBIAF */
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#endif
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	/* check for locked account */
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	if (!options.use_pam && passwd && *passwd) {
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		int locked = 0;
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#ifdef LOCKED_PASSWD_STRING
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		if (strcmp(passwd, LOCKED_PASSWD_STRING) == 0)
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			 locked = 1;
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#endif
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#ifdef LOCKED_PASSWD_PREFIX
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		if (strncmp(passwd, LOCKED_PASSWD_PREFIX,
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		    strlen(LOCKED_PASSWD_PREFIX)) == 0)
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			 locked = 1;
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#endif
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#ifdef LOCKED_PASSWD_SUBSTR
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		if (strstr(passwd, LOCKED_PASSWD_SUBSTR))
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			locked = 1;
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#endif
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#ifdef USE_LIBIAF
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		free((void *) passwd);
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#endif /* USE_LIBIAF */
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		if (locked) {
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			logit("User %.100s not allowed because account is locked",
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			    pw->pw_name);
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			return 0;
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		}
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	}
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	/*
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	 * Deny if shell does not exist or is not executable unless we
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	 * are chrooting.
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	 */
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	if (options.chroot_directory == NULL ||
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	    strcasecmp(options.chroot_directory, "none") == 0) {
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		char *shell = xstrdup((pw->pw_shell[0] == '\0') ?
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		    _PATH_BSHELL : pw->pw_shell); /* empty = /bin/sh */
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		if (stat(shell, &st) != 0) {
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			logit("User %.100s not allowed because shell %.100s "
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			    "does not exist", pw->pw_name, shell);
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			free(shell);
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			return 0;
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		}
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#ifndef WIN32_FIXME//R
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		if (S_ISREG(st.st_mode) == 0 ||
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		    (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP)) == 0) {
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			logit("User %.100s not allowed because shell %.100s "
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			    "is not executable", pw->pw_name, shell);
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			free(shell);
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			return 0;
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		}
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#endif
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		free(shell);
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	}
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	if (options.num_deny_users > 0 || options.num_allow_users > 0 ||
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	    options.num_deny_groups > 0 || options.num_allow_groups > 0) {
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		hostname = get_canonical_hostname(options.use_dns);
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		ipaddr = get_remote_ipaddr();
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	}
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	/* Return false if user is listed in DenyUsers */
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	if (options.num_deny_users > 0) {
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		for (i = 0; i < options.num_deny_users; i++)
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			if (match_user(pw->pw_name, hostname, ipaddr,
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			    options.deny_users[i])) {
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				logit("User %.100s from %.100s not allowed "
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				    "because listed in DenyUsers",
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				    pw->pw_name, hostname);
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				return 0;
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			}
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	}
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	/* Return false if AllowUsers isn't empty and user isn't listed there */
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	if (options.num_allow_users > 0) {
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		for (i = 0; i < options.num_allow_users; i++)
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			if (match_user(pw->pw_name, hostname, ipaddr,
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			    options.allow_users[i]))
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				break;
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		/* i < options.num_allow_users iff we break for loop */
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		if (i >= options.num_allow_users) {
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			logit("User %.100s from %.100s not allowed because "
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			    "not listed in AllowUsers", pw->pw_name, hostname);
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			return 0;
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		}
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	}
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	if (options.num_deny_groups > 0 || options.num_allow_groups > 0) {
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		/* Get the user's group access list (primary and supplementary) */
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		if (ga_init(pw->pw_name, pw->pw_gid) == 0) {
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			logit("User %.100s from %.100s not allowed because "
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			    "not in any group", pw->pw_name, hostname);
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			return 0;
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		}
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		/* Return false if one of user's groups is listed in DenyGroups */
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		if (options.num_deny_groups > 0)
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			if (ga_match(options.deny_groups,
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			    options.num_deny_groups)) {
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				ga_free();
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				logit("User %.100s from %.100s not allowed "
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				    "because a group is listed in DenyGroups",
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				    pw->pw_name, hostname);
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				return 0;
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			}
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		/*
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		 * Return false if AllowGroups isn't empty and one of user's groups
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		 * isn't listed there
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		 */
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		if (options.num_allow_groups > 0)
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			if (!ga_match(options.allow_groups,
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			    options.num_allow_groups)) {
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				ga_free();
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				logit("User %.100s from %.100s not allowed "
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				    "because none of user's groups are listed "
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				    "in AllowGroups", pw->pw_name, hostname);
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				return 0;
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			}
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		ga_free();
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	}
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#ifdef CUSTOM_SYS_AUTH_ALLOWED_USER
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	if (!sys_auth_allowed_user(pw, &loginmsg))
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		return 0;
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#endif
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	/* We found no reason not to let this user try to log on... */
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	return 1;
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}
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void
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auth_info(Authctxt *authctxt, const char *fmt, ...)
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{
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	va_list ap;
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        int i;
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	free(authctxt->info);
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	authctxt->info = NULL;
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	va_start(ap, fmt);
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	i = vasprintf(&authctxt->info, fmt, ap);
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	va_end(ap);
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	if (i < 0 || authctxt->info == NULL)
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		fatal("vasprintf failed");
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}
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void
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auth_log(Authctxt *authctxt, int authenticated, int partial,
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    const char *method, const char *submethod)
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{
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	void (*authlog) (const char *fmt,...) = verbose;
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	char *authmsg;
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	if (use_privsep && !mm_is_monitor() && !authctxt->postponed)
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		return;
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	/* Raise logging level */
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	if (authenticated == 1 ||
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	    !authctxt->valid ||
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	    authctxt->failures >= options.max_authtries / 2 ||
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	    strcmp(method, "password") == 0)
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		authlog = logit;
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	if (authctxt->postponed)
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		authmsg = "Postponed";
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	else if (partial)
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		authmsg = "Partial";
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	else
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		authmsg = authenticated ? "Accepted" : "Failed";
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	authlog("%s %s%s%s for %s%.100s from %.200s port %d %s%s%s",
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	    authmsg,
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	    method,
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	    submethod != NULL ? "/" : "", submethod == NULL ? "" : submethod,
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	    authctxt->valid ? "" : "invalid user ",
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	    authctxt->user,
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	    get_remote_ipaddr(),
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	    get_remote_port(),
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	    compat20 ? "ssh2" : "ssh1",
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	    authctxt->info != NULL ? ": " : "",
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	    authctxt->info != NULL ? authctxt->info : "");
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	free(authctxt->info);
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	authctxt->info = NULL;
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#ifdef CUSTOM_FAILED_LOGIN
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	if (authenticated == 0 && !authctxt->postponed &&
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	    (strcmp(method, "password") == 0 ||
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	    strncmp(method, "keyboard-interactive", 20) == 0 ||
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	    strcmp(method, "challenge-response") == 0))
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		record_failed_login(authctxt->user,
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		    get_canonical_hostname(options.use_dns), "ssh");
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# ifdef WITH_AIXAUTHENTICATE
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	if (authenticated)
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		sys_auth_record_login(authctxt->user,
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		    get_canonical_hostname(options.use_dns), "ssh", &loginmsg);
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# endif
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#endif
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#ifdef SSH_AUDIT_EVENTS
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	if (authenticated == 0 && !authctxt->postponed)
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		audit_event(audit_classify_auth(method));
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#endif
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}
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void
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auth_maxtries_exceeded(Authctxt *authctxt)
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{
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	error("maximum authentication attempts exceeded for "
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	    "%s%.100s from %.200s port %d %s",
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	    authctxt->valid ? "" : "invalid user ",
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	    authctxt->user,
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	    get_remote_ipaddr(),
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	    get_remote_port(),
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	    compat20 ? "ssh2" : "ssh1");
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	packet_disconnect("Too many authentication failures");
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	/* NOTREACHED */
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}
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/*
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 * Check whether root logins are disallowed.
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 */
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int
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auth_root_allowed(const char *method)
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{
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	switch (options.permit_root_login) {
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	case PERMIT_YES:
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		return 1;
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	case PERMIT_NO_PASSWD:
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		if (strcmp(method, "publickey") == 0 ||
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		    strcmp(method, "hostbased") == 0 ||
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		    strcmp(method, "gssapi-with-mic") == 0)
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			return 1;
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		break;
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	case PERMIT_FORCED_ONLY:
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						|
		if (forced_command) {
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			logit("Root login accepted for forced command.");
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			return 1;
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						|
		}
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		break;
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	}
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	logit("ROOT LOGIN REFUSED FROM %.200s", get_remote_ipaddr());
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	return 0;
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}
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/*
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						|
 * Given a template and a passwd structure, build a filename
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						|
 * by substituting % tokenised options. Currently, %% becomes '%',
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						|
 * %h becomes the home directory and %u the username.
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 *
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 * This returns a buffer allocated by xmalloc.
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 */
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						|
 
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/*
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 * Win32 implementation uses UTF16 names.
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 */
 | 
						|
 
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#ifdef WIN32_FIXME
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wchar_t *expand_authorized_keys(const wchar_t *filename, struct passwd *pw)
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						|
{
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  wchar_t *file_w, ret[MAXPATHLEN], pw_name_w[MAXPATHLEN], filename_w[MAXPATHLEN];
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						|
  int i;
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						|
  
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  wchar_t *slash;
 | 
						|
  
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  i = MultiByteToWideChar(CP_UTF8, 0, filename, -1, filename_w, MAXPATHLEN);
 | 
						|
  
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  if (i == 0)
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						|
  {
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    fatal("expand_authorized_keys: unable to convert path to UTF-16");
 | 
						|
  }  
 | 
						|
  
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  MultiByteToWideChar(CP_UTF8, 0, pw -> pw_name, -1, pw_name_w, MAXPATHLEN);
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						|
  
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  if (i == 0)
 | 
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  {
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    fatal("expand_authorized_keys: unable to convert path to UTF-16");
 | 
						|
  }
 | 
						|
  
 | 
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  file_w = percent_expand_w(filename_w, L"h", pw -> pw_dir,
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						|
                                L"u", pw_name_w, (char *) NULL);
 | 
						|
  
 | 
						|
  /*
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						|
   * Replace '/'  with '\'
 | 
						|
   */
 | 
						|
 | 
						|
  slash = file_w; 
 | 
						|
  
 | 
						|
  while ((slash = wcschr(slash, L'/')))
 | 
						|
  {
 | 
						|
    *slash = L'\\';
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						|
  }
 | 
						|
  
 | 
						|
  /*
 | 
						|
   * Absolute path given.
 | 
						|
   */
 | 
						|
   
 | 
						|
  if (wcschr(file_w, ':'))
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						|
  {
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						|
    i = _snwprintf(ret, sizeof(ret), L"%ls", file_w);
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						|
  }
 | 
						|
   
 | 
						|
  /*
 | 
						|
   * Relative path given. Expand to user homedir.
 | 
						|
   */
 | 
						|
   
 | 
						|
  else
 | 
						|
  {
 | 
						|
    i = _snwprintf(ret, sizeof(ret), L"%ls\\%ls", pw->pw_dir, file_w);
 | 
						|
  }  
 | 
						|
  
 | 
						|
  if (i < 0 || (size_t) i >= sizeof(ret))
 | 
						|
  {  
 | 
						|
    fatal("expand_authorized_keys: path too long");
 | 
						|
  }  
 | 
						|
 | 
						|
  free(file_w);
 | 
						|
  
 | 
						|
  return (_wcsdup(ret));
 | 
						|
}
 | 
						|
 | 
						|
#else /* WIN32_FIXME */
 | 
						|
 | 
						|
char *
 | 
						|
expand_authorized_keys(const char *filename, struct passwd *pw)
 | 
						|
{
 | 
						|
	char *file, ret[PATH_MAX];
 | 
						|
	int i;
 | 
						|
 | 
						|
	file = percent_expand(filename, "h", pw->pw_dir,
 | 
						|
	    "u", pw->pw_name, (char *)NULL);
 | 
						|
 | 
						|
	/*
 | 
						|
	 * Ensure that filename starts anchored. If not, be backward
 | 
						|
	 * compatible and prepend the '%h/'
 | 
						|
	 */
 | 
						|
	if (*file == '/')
 | 
						|
		return (file);
 | 
						|
 | 
						|
	i = snprintf(ret, sizeof(ret), "%s/%s", pw->pw_dir, file);
 | 
						|
	if (i < 0 || (size_t)i >= sizeof(ret))
 | 
						|
		fatal("expand_authorized_keys: path too long");
 | 
						|
	free(file);
 | 
						|
	return (xstrdup(ret));
 | 
						|
}
 | 
						|
#endif /* WIN32_FIXME */
 | 
						|
 | 
						|
char *
 | 
						|
authorized_principals_file(struct passwd *pw)
 | 
						|
{
 | 
						|
	if (options.authorized_principals_file == NULL)
 | 
						|
		return NULL;
 | 
						|
	return expand_authorized_keys(options.authorized_principals_file, pw);
 | 
						|
}
 | 
						|
 | 
						|
/* return ok if key exists in sysfile or userfile */
 | 
						|
HostStatus
 | 
						|
check_key_in_hostfiles(struct passwd *pw, Key *key, const char *host,
 | 
						|
    const char *sysfile, const char *userfile)
 | 
						|
{
 | 
						|
	char *user_hostfile;
 | 
						|
	struct stat st;
 | 
						|
	HostStatus host_status;
 | 
						|
	struct hostkeys *hostkeys;
 | 
						|
	const struct hostkey_entry *found;
 | 
						|
 | 
						|
	hostkeys = init_hostkeys();
 | 
						|
	load_hostkeys(hostkeys, host, sysfile);
 | 
						|
	if (userfile != NULL) {
 | 
						|
		user_hostfile = tilde_expand_filename(userfile, pw->pw_uid);
 | 
						|
		if (options.strict_modes &&
 | 
						|
		    (stat(user_hostfile, &st) == 0) &&
 | 
						|
		    ((st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
 | 
						|
		    (st.st_mode & 022) != 0)) {
 | 
						|
			logit("Authentication refused for %.100s: "
 | 
						|
			    "bad owner or modes for %.200s",
 | 
						|
			    pw->pw_name, user_hostfile);
 | 
						|
			auth_debug_add("Ignored %.200s: bad ownership or modes",
 | 
						|
			    user_hostfile);
 | 
						|
		} else {
 | 
						|
			temporarily_use_uid(pw);
 | 
						|
			load_hostkeys(hostkeys, host, user_hostfile);
 | 
						|
			restore_uid();
 | 
						|
		}
 | 
						|
		free(user_hostfile);
 | 
						|
	}
 | 
						|
	host_status = check_key_in_hostkeys(hostkeys, key, &found);
 | 
						|
	if (host_status == HOST_REVOKED)
 | 
						|
		error("WARNING: revoked key for %s attempted authentication",
 | 
						|
		    found->host);
 | 
						|
	else if (host_status == HOST_OK)
 | 
						|
		debug("%s: key for %s found at %s:%ld", __func__,
 | 
						|
		    found->host, found->file, found->line);
 | 
						|
	else
 | 
						|
		debug("%s: key for host %s not found", __func__, host);
 | 
						|
 | 
						|
	free_hostkeys(hostkeys);
 | 
						|
 | 
						|
	return host_status;
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * Check a given path for security. This is defined as all components
 | 
						|
 * of the path to the file must be owned by either the owner of
 | 
						|
 * of the file or root and no directories must be group or world writable.
 | 
						|
 *
 | 
						|
 * XXX Should any specific check be done for sym links ?
 | 
						|
 *
 | 
						|
 * Takes a file name, its stat information (preferably from fstat() to
 | 
						|
 * avoid races), the uid of the expected owner, their home directory and an
 | 
						|
 * error buffer plus max size as arguments.
 | 
						|
 *
 | 
						|
 * Returns 0 on success and -1 on failure
 | 
						|
 */
 | 
						|
int
 | 
						|
auth_secure_path(const char *name, struct stat *stp, const char *pw_dir,
 | 
						|
    uid_t uid, char *err, size_t errlen)
 | 
						|
{
 | 
						|
#ifndef WIN32_FIXME
 | 
						|
	char buf[PATH_MAX], homedir[PATH_MAX];
 | 
						|
	char *cp;
 | 
						|
	int comparehome = 0;
 | 
						|
	struct stat st;
 | 
						|
 | 
						|
	if (realpath(name, buf) == NULL) {
 | 
						|
		snprintf(err, errlen, "realpath %s failed: %s", name,
 | 
						|
		    strerror(errno));
 | 
						|
		return -1;
 | 
						|
	}
 | 
						|
	if (pw_dir != NULL && realpath(pw_dir, homedir) != NULL)
 | 
						|
		comparehome = 1;
 | 
						|
 | 
						|
	if (!S_ISREG(stp->st_mode)) {
 | 
						|
		snprintf(err, errlen, "%s is not a regular file", buf);
 | 
						|
		return -1;
 | 
						|
	}
 | 
						|
	if ((!platform_sys_dir_uid(stp->st_uid) && stp->st_uid != uid) ||
 | 
						|
	    (stp->st_mode & 022) != 0) {
 | 
						|
		snprintf(err, errlen, "bad ownership or modes for file %s",
 | 
						|
		    buf);
 | 
						|
		return -1;
 | 
						|
	}
 | 
						|
 | 
						|
	/* for each component of the canonical path, walking upwards */
 | 
						|
	for (;;) {
 | 
						|
		if ((cp = dirname(buf)) == NULL) {
 | 
						|
			snprintf(err, errlen, "dirname() failed");
 | 
						|
			return -1;
 | 
						|
		}
 | 
						|
		strlcpy(buf, cp, sizeof(buf));
 | 
						|
 | 
						|
		if (stat(buf, &st) < 0 ||
 | 
						|
		    (!platform_sys_dir_uid(st.st_uid) && st.st_uid != uid) ||
 | 
						|
		    (st.st_mode & 022) != 0) {
 | 
						|
			snprintf(err, errlen,
 | 
						|
			    "bad ownership or modes for directory %s", buf);
 | 
						|
			return -1;
 | 
						|
		}
 | 
						|
 | 
						|
		/* If are past the homedir then we can stop */
 | 
						|
		if (comparehome && strcmp(homedir, buf) == 0)
 | 
						|
			break;
 | 
						|
 | 
						|
		/*
 | 
						|
		 * dirname should always complete with a "/" path,
 | 
						|
		 * but we can be paranoid and check for "." too
 | 
						|
		 */
 | 
						|
		if ((strcmp("/", buf) == 0) || (strcmp(".", buf) == 0))
 | 
						|
			break;
 | 
						|
	}
 | 
						|
	return 0;
 | 
						|
#else
 | 
						|
  return 0;
 | 
						|
#endif 
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * Version of secure_path() that accepts an open file descriptor to
 | 
						|
 * avoid races.
 | 
						|
 *
 | 
						|
 * Returns 0 on success and -1 on failure
 | 
						|
 */
 | 
						|
static int
 | 
						|
secure_filename(FILE *f, const char *file, struct passwd *pw,
 | 
						|
    char *err, size_t errlen)
 | 
						|
{
 | 
						|
#ifndef WIN32_FIXME
 | 
						|
	struct stat st;
 | 
						|
 | 
						|
	/* check the open file to avoid races */
 | 
						|
	if (fstat(fileno(f), &st) < 0) {
 | 
						|
		snprintf(err, errlen, "cannot stat file %s: %s",
 | 
						|
		    file, strerror(errno));
 | 
						|
		return -1;
 | 
						|
	}
 | 
						|
	return auth_secure_path(file, &st, pw->pw_dir, pw->pw_uid, err, errlen);
 | 
						|
#else
 | 
						|
  return 0;
 | 
						|
#endif 
 | 
						|
}
 | 
						|
 | 
						|
static FILE *
 | 
						|
auth_openfile(const char *file, struct passwd *pw, int strict_modes,
 | 
						|
    int log_missing, char *file_type)
 | 
						|
{
 | 
						|
	char line[1024];
 | 
						|
	struct stat st;
 | 
						|
	int fd;
 | 
						|
	FILE *f;
 | 
						|
	
 | 
						|
#ifdef WIN32_FIXME
 | 
						|
    if ((fd = _wopen(file, O_RDONLY|O_NONBLOCK)) == -1) {
 | 
						|
#else
 | 
						|
	if ((fd = open(file, O_RDONLY|O_NONBLOCK)) == -1) {
 | 
						|
#endif
 | 
						|
		if (log_missing || errno != ENOENT)
 | 
						|
			debug("Could not open %s '%s': %s", file_type, file,
 | 
						|
			   strerror(errno));
 | 
						|
		return NULL;
 | 
						|
	}
 | 
						|
 | 
						|
#ifdef WIN32_FIXME
 | 
						|
	if ((f = _fdopen(fd, "r")) == NULL) {
 | 
						|
		_close(fd);
 | 
						|
		return NULL;
 | 
						|
	}
 | 
						|
 | 
						|
#else
 | 
						|
	if (fstat(fd, &st) < 0) {
 | 
						|
		close(fd);
 | 
						|
		return NULL;
 | 
						|
	}
 | 
						|
	if (!S_ISREG(st.st_mode)) {
 | 
						|
		logit("User %s %s %s is not a regular file",
 | 
						|
		    pw->pw_name, file_type, file);
 | 
						|
		close(fd);
 | 
						|
		return NULL;
 | 
						|
	}
 | 
						|
	unset_nonblock(fd);
 | 
						|
 | 
						|
	if ((f = fdopen(fd, "r")) == NULL) {
 | 
						|
		close(fd);
 | 
						|
		return NULL;
 | 
						|
	}
 | 
						|
#endif
 | 
						|
	if (strict_modes &&
 | 
						|
	    secure_filename(f, file, pw, line, sizeof(line)) != 0) {
 | 
						|
		fclose(f);
 | 
						|
		logit("Authentication refused: %s", line);
 | 
						|
		auth_debug_add("Ignored %s: %s", file_type, line);
 | 
						|
		return NULL;
 | 
						|
	}
 | 
						|
 | 
						|
	return f;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
FILE *
 | 
						|
auth_openkeyfile(const char *file, struct passwd *pw, int strict_modes)
 | 
						|
{
 | 
						|
	return auth_openfile(file, pw, strict_modes, 1, "authorized keys");
 | 
						|
}
 | 
						|
 | 
						|
FILE *
 | 
						|
auth_openprincipals(const char *file, struct passwd *pw, int strict_modes)
 | 
						|
{
 | 
						|
	return auth_openfile(file, pw, strict_modes, 0,
 | 
						|
	    "authorized principals");
 | 
						|
}
 | 
						|
 | 
						|
struct passwd *
 | 
						|
getpwnamallow(const char *user)
 | 
						|
{
 | 
						|
#ifdef HAVE_LOGIN_CAP
 | 
						|
	extern login_cap_t *lc;
 | 
						|
#ifdef BSD_AUTH
 | 
						|
	auth_session_t *as;
 | 
						|
#endif
 | 
						|
#endif
 | 
						|
	struct passwd *pw;
 | 
						|
	struct connection_info *ci = get_connection_info(1, options.use_dns);
 | 
						|
 | 
						|
	ci->user = user;
 | 
						|
	parse_server_match_config(&options, ci);
 | 
						|
 | 
						|
#if defined(_AIX) && defined(HAVE_SETAUTHDB)
 | 
						|
	aix_setauthdb(user);
 | 
						|
#endif
 | 
						|
 | 
						|
	pw = getpwnam(user);
 | 
						|
 | 
						|
#if defined(_AIX) && defined(HAVE_SETAUTHDB)
 | 
						|
	aix_restoreauthdb();
 | 
						|
#endif
 | 
						|
#ifdef HAVE_CYGWIN
 | 
						|
	/*
 | 
						|
	 * Windows usernames are case-insensitive.  To avoid later problems
 | 
						|
	 * when trying to match the username, the user is only allowed to
 | 
						|
	 * login if the username is given in the same case as stored in the
 | 
						|
	 * user database.
 | 
						|
	 */
 | 
						|
	if (pw != NULL && strcmp(user, pw->pw_name) != 0) {
 | 
						|
		logit("Login name %.100s does not match stored username %.100s",
 | 
						|
		    user, pw->pw_name);
 | 
						|
		pw = NULL;
 | 
						|
	}
 | 
						|
#endif
 | 
						|
	if (pw == NULL) {
 | 
						|
		logit("Invalid user %.100s from %.100s",
 | 
						|
		    user, get_remote_ipaddr());
 | 
						|
#ifdef CUSTOM_FAILED_LOGIN
 | 
						|
		record_failed_login(user,
 | 
						|
		    get_canonical_hostname(options.use_dns), "ssh");
 | 
						|
#endif
 | 
						|
#ifdef SSH_AUDIT_EVENTS
 | 
						|
		audit_event(SSH_INVALID_USER);
 | 
						|
#endif /* SSH_AUDIT_EVENTS */
 | 
						|
		return (NULL);
 | 
						|
	}
 | 
						|
	if (!allowed_user(pw))
 | 
						|
		return (NULL);
 | 
						|
#ifdef HAVE_LOGIN_CAP
 | 
						|
	if ((lc = login_getclass(pw->pw_class)) == NULL) {
 | 
						|
		debug("unable to get login class: %s", user);
 | 
						|
		return (NULL);
 | 
						|
	}
 | 
						|
#ifdef BSD_AUTH
 | 
						|
	if ((as = auth_open()) == NULL || auth_setpwd(as, pw) != 0 ||
 | 
						|
	    auth_approval(as, lc, pw->pw_name, "ssh") <= 0) {
 | 
						|
		debug("Approval failure for %s", user);
 | 
						|
		pw = NULL;
 | 
						|
	}
 | 
						|
	if (as != NULL)
 | 
						|
		auth_close(as);
 | 
						|
#endif
 | 
						|
#endif
 | 
						|
	if (pw != NULL)
 | 
						|
		return (pwcopy(pw));
 | 
						|
	return (NULL);
 | 
						|
}
 | 
						|
 | 
						|
/* Returns 1 if key is revoked by revoked_keys_file, 0 otherwise */
 | 
						|
int
 | 
						|
auth_key_is_revoked(Key *key)
 | 
						|
{
 | 
						|
	char *fp = NULL;
 | 
						|
	int r;
 | 
						|
 | 
						|
	if (options.revoked_keys_file == NULL)
 | 
						|
		return 0;
 | 
						|
	if ((fp = sshkey_fingerprint(key, options.fingerprint_hash,
 | 
						|
	    SSH_FP_DEFAULT)) == NULL) {
 | 
						|
		r = SSH_ERR_ALLOC_FAIL;
 | 
						|
		error("%s: fingerprint key: %s", __func__, ssh_err(r));
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
 | 
						|
	r = sshkey_check_revoked(key, options.revoked_keys_file);
 | 
						|
	switch (r) {
 | 
						|
	case 0:
 | 
						|
		break; /* not revoked */
 | 
						|
	case SSH_ERR_KEY_REVOKED:
 | 
						|
		error("Authentication key %s %s revoked by file %s",
 | 
						|
		    sshkey_type(key), fp, options.revoked_keys_file);
 | 
						|
		goto out;
 | 
						|
	default:
 | 
						|
		error("Error checking authentication key %s %s in "
 | 
						|
		    "revoked keys file %s: %s", sshkey_type(key), fp,
 | 
						|
		    options.revoked_keys_file, ssh_err(r));
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
 | 
						|
	/* Success */
 | 
						|
	r = 0;
 | 
						|
 | 
						|
 out:
 | 
						|
	free(fp);
 | 
						|
	return r == 0 ? 0 : 1;
 | 
						|
}
 | 
						|
 | 
						|
void
 | 
						|
auth_debug_add(const char *fmt,...)
 | 
						|
{
 | 
						|
	char buf[1024];
 | 
						|
	va_list args;
 | 
						|
 | 
						|
	if (!auth_debug_init)
 | 
						|
		return;
 | 
						|
 | 
						|
	va_start(args, fmt);
 | 
						|
	vsnprintf(buf, sizeof(buf), fmt, args);
 | 
						|
	va_end(args);
 | 
						|
	buffer_put_cstring(&auth_debug, buf);
 | 
						|
}
 | 
						|
 | 
						|
void
 | 
						|
auth_debug_send(void)
 | 
						|
{
 | 
						|
	char *msg;
 | 
						|
 | 
						|
	if (!auth_debug_init)
 | 
						|
		return;
 | 
						|
	while (buffer_len(&auth_debug)) {
 | 
						|
		msg = buffer_get_string(&auth_debug, NULL);
 | 
						|
		packet_send_debug("%s", msg);
 | 
						|
		free(msg);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
void
 | 
						|
auth_debug_reset(void)
 | 
						|
{
 | 
						|
	if (auth_debug_init)
 | 
						|
		buffer_clear(&auth_debug);
 | 
						|
	else {
 | 
						|
		buffer_init(&auth_debug);
 | 
						|
		auth_debug_init = 1;
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
struct passwd *
 | 
						|
fakepw(void)
 | 
						|
{
 | 
						|
	static struct passwd fake;
 | 
						|
 | 
						|
	memset(&fake, 0, sizeof(fake));
 | 
						|
	fake.pw_name = "NOUSER";
 | 
						|
	fake.pw_passwd =
 | 
						|
	    "$2a$06$r3.juUaHZDlIbQaO2dS9FuYxL1W9M81R1Tc92PoSNmzvpEqLkLGrK";
 | 
						|
#ifdef HAVE_STRUCT_PASSWD_PW_GECOS
 | 
						|
	fake.pw_gecos = "NOUSER";
 | 
						|
#endif
 | 
						|
	fake.pw_uid = privsep_pw == NULL ? (uid_t)-1 : privsep_pw->pw_uid;
 | 
						|
	fake.pw_gid = privsep_pw == NULL ? (gid_t)-1 : privsep_pw->pw_gid;
 | 
						|
#ifdef HAVE_STRUCT_PASSWD_PW_CLASS
 | 
						|
	fake.pw_class = "";
 | 
						|
#endif
 | 
						|
	fake.pw_dir = "/nonexist";
 | 
						|
	fake.pw_shell = "/nonexist";
 | 
						|
 | 
						|
	return (&fake);
 | 
						|
}
 |