/* 
   Unix SMB/Netbios implementation.
   Version 1.9.
   Password and authentication handling
   Copyright (C) Andrew Tridgell              1992-2000
   Copyright (C) Luke Kenneth Casson Leighton 1996-2000
   Copyright (C) Andrew Bartlett              2001
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "includes.h"

/****************************************************************************
 Check user is in correct domain if required
****************************************************************************/

static BOOL check_domain_match(char *user, char *domain) 
{
  /*
   * If we aren't serving to trusted domains, we must make sure that
   * the validation request comes from an account in the same domain
   * as the Samba server
   */

  if (!lp_allow_trusted_domains() &&
      !strequal(lp_workgroup(), domain) ) {
      DEBUG(1, ("check_domain_match: Attempt to connect as user %s from domain %s denied.\n", user, domain));
      return False;
  } else {
      return True;
  }
}

/****************************************************************************
 Check a users password, as given in the user-info struct and return various
 interesting details in the server_info struct.

 This functions does NOT need to be in a become_root()/unbecome_root() pair
 as it makes the calls itself when needed.
****************************************************************************/

NTSTATUS check_password(const auth_usersupplied_info *user_info, 
			auth_serversupplied_info *server_info)
{
	
	NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
	BOOL done_pam = False;
	
	DEBUG(3, ("check_password:  Checking password for smb user %s\\%s@%s with the new password interface\n", 
		  user_info->smb_username.str, user_info->requested_domain.str, user_info->wksta_name.str));
  	if (!check_domain_match(user_info->smb_username.str, user_info->domain.str)) {
		return NT_STATUS_LOGON_FAILURE;
	}

	if (!NT_STATUS_IS_OK(nt_status)) {
		nt_status = check_rhosts_security(user_info, server_info);
	}
	
	if ((lp_security() == SEC_DOMAIN) && !NT_STATUS_IS_OK(nt_status)) {
		nt_status = check_domain_security(user_info, server_info);
	}
	
	if ((lp_security() == SEC_SERVER) && !NT_STATUS_IS_OK(nt_status)) {
		nt_status = check_server_security(user_info, server_info);
	}

	if (lp_security() >= SEC_SERVER) {
		smb_user_control(user_info->unix_username.str, nt_status);
	}

	if (!NT_STATUS_IS_OK(nt_status)) {
		if ((user_info->plaintext_password.len > 0) 
		    && (!lp_plaintext_to_smbpasswd())) {
			nt_status = check_unix_security(user_info, server_info);
			done_pam = True;
		} else { 
			nt_status = check_smbpasswd_security(user_info, server_info);
		}
	}

	if (NT_STATUS_IS_OK(nt_status) && !done_pam) {
		/* We might not be root if we are an RPC call */
		become_root();
		nt_status = smb_pam_accountcheck(user_info->unix_username.str);
		unbecome_root();
	}
	
	if (NT_STATUS_IS_OK(nt_status)) {
		DEBUG(5, ("check_password:  Password for smb user %s suceeded\n", user_info->smb_username.str));
	} else {
		DEBUG(3, ("check_password:  Password for smb user %s FAILED with error %s\n", user_info->smb_username.str, get_nt_error_msg(nt_status)));

	}		
	return nt_status;

}

/****************************************************************************
 COMPATABILITY INTERFACES:
 ***************************************************************************/

/****************************************************************************
check if a username/password is OK assuming the password is a 24 byte
SMB hash
return True if the password is correct, False otherwise
****************************************************************************/

NTSTATUS pass_check_smb_with_chal(char *smb_user, char *unix_user, 
                                  char *domain, char* workstation, 
				  uchar chal[8], 
				  uchar *lm_pwd, int lm_pwd_len,
				  uchar *nt_pwd, int nt_pwd_len)
{

	auth_usersupplied_info user_info;
	auth_serversupplied_info server_info;
	AUTH_STR ourdomain, theirdomain, unix_username, smb_username, 
                wksta_name;
		
	ZERO_STRUCT(user_info);
	ZERO_STRUCT(ourdomain);
	ZERO_STRUCT(theirdomain);
	ZERO_STRUCT(smb_username);
	ZERO_STRUCT(wksta_name);
	
	ourdomain.str = lp_workgroup();
	ourdomain.len = strlen(ourdomain.str);

	theirdomain.str = domain;
	theirdomain.len = strlen(theirdomain.str);

	user_info.requested_domain = theirdomain;
	user_info.domain = ourdomain;
	
	smb_username.str = smb_user;
	smb_username.len = strlen(smb_username.str);

        /* If unix user is NULL, use smb user */

	unix_username.str = unix_user ? unix_user : smb_user;
	unix_username.len = strlen(unix_username.str);

	user_info.unix_username = unix_username;
	user_info.smb_username = smb_username;

	wksta_name.str = workstation;
	wksta_name.len = strlen(workstation);

	user_info.wksta_name = wksta_name;

	memcpy(user_info.chal, chal, 8);

	if ((lm_pwd_len >= 24 || nt_pwd_len >= 24) || 
	    (lp_encrypted_passwords() && (lm_pwd_len == 0) && lp_null_passwords())) {
		/* if 24 bytes long assume it is an encrypted password */
	  
		user_info.lm_resp.buffer = (uint8 *)lm_pwd;
		user_info.lm_resp.len = lm_pwd_len;
		user_info.nt_resp.buffer = (uint8 *)nt_pwd;
		user_info.nt_resp.len = nt_pwd_len;

	} else {
		unsigned char local_lm_response[24];
		unsigned char local_nt_response[24];
		
		/*
		 * Not encrypted - do so.
		 */
		
		DEBUG(5,("pass_check_smb: User passwords not in encrypted format.\n"));

		if (lm_pwd_len > 0) {
			SMBencrypt( (uchar *)lm_pwd, user_info.chal, local_lm_response);
			user_info.lm_resp.buffer = (uint8 *)local_lm_response;
			user_info.lm_resp.len = 24;


			/* WATCH OUT. This doesn't work if the incoming password is incorrectly cased. 
			   We might want to add a check here and only do an LM in that case */

			/* This encrypts the lm_pwd feild, which actualy contains the password
			   rather than the nt_pwd field becouse that contains nothing */
			SMBNTencrypt((uchar *)lm_pwd, user_info.chal, local_nt_response);
			user_info.nt_resp.buffer = (uint8 *)local_nt_response;
			user_info.nt_resp.len = 24;
		}
		
		user_info.plaintext_password.str = (char *)lm_pwd;
		user_info.plaintext_password.len = lm_pwd_len;

	}

	return check_password(&user_info, &server_info);
}

NTSTATUS pass_check_smb(char *smb_user, char *unix_user, 
			char *domain, char *workstation,
			uchar *lm_pwd, int lm_pwd_len,
			uchar *nt_pwd, int nt_pwd_len)
{
	uchar chal[8];

	if (!last_challenge(chal)) {
		generate_random_buffer( chal, 8, False);
	}

	return pass_check_smb_with_chal(smb_user, unix_user, 
					domain, workstation, chal, 
					lm_pwd, lm_pwd_len,
					nt_pwd, nt_pwd_len);

}

/****************************************************************************
check if a username/password pair is OK either via the system password
database or the encrypted SMB password database
return True if the password is correct, False otherwise
****************************************************************************/
BOOL password_ok(char *user, char *password, int pwlen)
{
	extern fstring remote_machine;

	/* 
	 *  This hack must die!  But until I rewrite the rest of samba
	 *  it must stay - abartlet 2001-08-03
	 */

	if ((pwlen == 0) && !lp_null_passwords()) {
                DEBUG(4,("Null passwords not allowed.\n"));
                return False;
        }
	
	/* The password could be either NTLM or plain LM.  Try NTLM first, but fall-through as
	   required. */
	if (NT_STATUS_IS_OK(pass_check_smb(user, NULL, remote_machine, lp_workgroup(), NULL, 0, (unsigned char *)password, pwlen))) {
		return True;
	}

	if (NT_STATUS_IS_OK(pass_check_smb(user, NULL, remote_machine, lp_workgroup(), (unsigned char *)password, pwlen, NULL, 0))) {
		return True;
	}

	return False;
}