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/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
* Created: Sat Mar 18 05:11:38 1995 ylo
* Password authentication. This file contains the functions to check whether
* the password is valid for the user.
*/
#include "includes.h"
#ifndef USE_PAM
RCSID("$Id: auth-passwd.c,v 1.15 2000/01/06 01:03:13 damien Exp $");
#include "packet.h"
#include "ssh.h"
#include "servconf.h"
#include "xmalloc.h"
#ifdef HAVE_SHADOW_H
# include <shadow.h>
#endif
#if defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT)
# include "md5crypt.h"
#endif /* defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT) */
/*
* Tries to authenticate the user using password. Returns true if
* authentication succeeds.
*/
int
auth_password(struct passwd * pw, const char *password)
{
extern ServerOptions options;
char *encrypted_password;
char *pw_password;
char *salt;
#ifdef HAVE_SHADOW_H
struct spwd *spw;
#endif
/* deny if no user. */
if (pw == NULL)
return 0;
if (pw->pw_uid == 0 && options.permit_root_login == 2)
return 0;
if (*password == '\0' && options.permit_empty_passwd == 0)
return 0;
#ifdef SKEY
if (options.skey_authentication == 1) {
int ret = auth_skey_password(pw, password);
if (ret == 1 || ret == 0)
return ret;
/* Fall back to ordinary passwd authentication. */
}
#endif
#ifdef KRB4
if (options.kerberos_authentication == 1) {
int ret = auth_krb4_password(pw, password);
if (ret == 1 || ret == 0)
return ret;
/* Fall back to ordinary passwd authentication. */
}
#endif
/* Check for users with no password. */
if (strcmp(password, "") == 0 && strcmp(pw->pw_passwd, "") == 0)
return 1;
pw_password = pw->pw_passwd;
#if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW)
spw = getspnam(pw->pw_name);
if (spw != NULL)
{
/* Check for users with no password. */
if (strcmp(password, "") == 0 && strcmp(spw->sp_pwdp, "") == 0)
return 1;
pw_password = spw->sp_pwdp;
}
#endif /* defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) */
if (pw_password[0] != '\0')
salt = pw_password;
else
salt = "xx";
#ifdef HAVE_MD5_PASSWORDS
if (is_md5_salt(salt))
encrypted_password = md5_crypt(password, salt);
else
encrypted_password = crypt(password, salt);
#else /* HAVE_MD5_PASSWORDS */
encrypted_password = crypt(password, salt);
#endif /* HAVE_MD5_PASSWORDS */
/* Authentication is accepted if the encrypted passwords are identical. */
return (strcmp(encrypted_password, pw_password) == 0);
}
#endif /* !USE_PAM */
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