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/*
Unix SMB/Netbios implementation.
Version 1.9.
Authenticate to a remote server
Copyright (C) Andrew Tridgell 1992-1998
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"
extern int DEBUGLEVEL;
extern pstring global_myname;
/****************************************************************************
Return the client state structure.
****************************************************************************/
struct cli_state *server_client(void)
{
static struct cli_state pw_cli;
return &pw_cli;
}
/****************************************************************************
Support for server level security.
****************************************************************************/
struct cli_state *server_cryptkey(void)
{
struct cli_state *cli;
fstring desthost;
struct in_addr dest_ip;
char *p, *pserver;
BOOL connected_ok = False;
cli = server_client();
if (!cli_initialise(cli))
return NULL;
pserver = strdup(lp_passwordserver());
p = pserver;
while(next_token( &p, desthost, LIST_SEP, sizeof(desthost))) {
standard_sub_basic(desthost);
strupper(desthost);
if(!resolve_name( desthost, &dest_ip, 0x20)) {
DEBUG(1,("server_cryptkey: Can't resolve address for %s\n",desthost));
continue;
}
if (ismyip(dest_ip)) {
DEBUG(1,("Password server loop - disabling password server %s\n",desthost));
continue;
}
if (cli_connect(cli, desthost, &dest_ip)) {
DEBUG(3,("connected to password server %s\n",desthost));
connected_ok = True;
break;
}
}
free(pserver);
if (!connected_ok) {
DEBUG(0,("password server not available\n"));
cli_shutdown(cli);
return NULL;
}
if (!attempt_netbios_session_request(cli, global_myname, desthost, &dest_ip))
return NULL;
DEBUG(3,("got session\n"));
if (!cli_negprot(cli)) {
DEBUG(1,("%s rejected the negprot\n",desthost));
cli_shutdown(cli);
return NULL;
}
if (cli->protocol < PROTOCOL_LANMAN2 ||
!(cli->sec_mode & 1)) {
DEBUG(1,("%s isn't in user level security mode\n",desthost));
cli_shutdown(cli);
return NULL;
}
DEBUG(3,("password server OK\n"));
return cli;
}
/****************************************************************************
Validate a password with the password server.
****************************************************************************/
static NTSTATUS server_validate(const auth_usersupplied_info *user_info, auth_serversupplied_info *server_info)
{
struct cli_state *cli;
static unsigned char badpass[24];
static fstring baduser;
static BOOL tested_password_server = False;
static BOOL bad_password_server = False;
NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
cli = server_client();
if (!cli->initialised) {
DEBUG(1,("password server %s is not connected\n", cli->desthost));
return(NT_STATUS_LOGON_FAILURE);
}
if(badpass[0] == 0)
memset(badpass, 0x1f, sizeof(badpass));
if((user_info->nt_resp.len == sizeof(badpass)) &&
!memcmp(badpass, user_info->nt_resp.buffer, sizeof(badpass))) {
/*
* Very unlikely, our random bad password is the same as the users
* password.
*/
memset(badpass, badpass[0]+1, sizeof(badpass));
}
if(baduser[0] == 0) {
fstrcpy(baduser, INVALID_USER_PREFIX);
fstrcat(baduser, global_myname);
}
/*
* Attempt a session setup with a totally incorrect password.
* If this succeeds with the guest bit *NOT* set then the password
* server is broken and is not correctly setting the guest bit. We
* need to detect this as some versions of NT4.x are broken. JRA.
*/
/* I sure as hell hope that there arn't servers out there that take
* NTLMv2 and have this bug, as we don't test for that...
* - abartlet@samba.org
*/
if ((!tested_password_server) && (lp_paranoid_server_security())) {
if (cli_session_setup(cli, baduser, (char *)badpass, sizeof(badpass),
(char *)badpass, sizeof(badpass), user_info->domain.str)) {
/*
* We connected to the password server so we
* can say we've tested it.
*/
tested_password_server = True;
if ((SVAL(cli->inbuf,smb_vwv2) & 1) == 0) {
DEBUG(0,("server_validate: password server %s allows users as non-guest \
with a bad password.\n", cli->desthost));
DEBUG(0,("server_validate: This is broken (and insecure) behaviour. Please do not \
use this machine as the password server.\n"));
cli_ulogoff(cli);
/*
* Password server has the bug.
*/
bad_password_server = True;
return NT_STATUS_LOGON_FAILURE;
}
cli_ulogoff(cli);
}
} else {
/*
* We have already tested the password server.
* Fail immediately if it has the bug.
*/
if(bad_password_server) {
DEBUG(0,("server_validate: [1] password server %s allows users as non-guest \
with a bad password.\n", cli->desthost));
DEBUG(0,("server_validate: [1] This is broken (and insecure) behaviour. Please do not \
use this machine as the password server.\n"));
return NT_STATUS_LOGON_FAILURE;
}
}
/*
* Now we know the password server will correctly set the guest bit, or is
* not guest enabled, we can try with the real password.
*/
if (!cli_session_setup(cli, user_info->smb_username.str,
(char *)user_info->lm_resp.buffer,
user_info->lm_resp.len,
(char *)user_info->nt_resp.buffer,
user_info->nt_resp.len,
user_info->domain.str)) {
DEBUG(1,("password server %s rejected the password\n", cli->desthost));
/* Make this cli_nt_error() when the conversion is in */
nt_status = NT_STATUS_LOGON_FAILURE;
} else {
nt_status = NT_STATUS_OK;
}
/* if logged in as guest then reject */
if ((SVAL(cli->inbuf,smb_vwv2) & 1) != 0) {
DEBUG(1,("password server %s gave us guest only\n", cli->desthost));
nt_status = NT_STATUS_LOGON_FAILURE;
}
cli_ulogoff(cli);
return(nt_status);
}
/****************************************************************************
Check for a valid username and password in security=server mode.
****************************************************************************/
NTSTATUS check_server_security(const auth_usersupplied_info *user_info, auth_serversupplied_info *server_info)
{
if(lp_security() != SEC_SERVER)
return NT_STATUS_LOGON_FAILURE;
return server_validate(user_info, server_info);
}
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