/*
Unix SMB/CIFS implementation.
Password and authentication handling
Copyright (C) Andrew Tridgell 1992-2000
Copyright (C) Luke Kenneth Casson Leighton 1996-2000
Copyright (C) Andrew Bartlett 2001-2003
Copyright (C) Gerald Carter 2003
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"
#undef DBGC_CLASS
#define DBGC_CLASS DBGC_AUTH
/****************************************************************************
Core of smb password checking routine.
****************************************************************************/
static BOOL smb_pwd_check_ntlmv1(const DATA_BLOB *nt_response,
const uchar *part_passwd,
const DATA_BLOB *sec_blob,
DATA_BLOB *user_sess_key)
{
/* Finish the encryption of part_passwd. */
uchar p24[24];
if (part_passwd == NULL) {
DEBUG(10,("No password set - DISALLOWING access\n"));
/* No password set - always false ! */
return False;
}
if (sec_blob->length != 8) {
DEBUG(0, ("smb_pwd_check_ntlmv1: incorrect challenge size (%lu)\n",
(unsigned long)sec_blob->length));
return False;
}
if (nt_response->length != 24) {
DEBUG(0, ("smb_pwd_check_ntlmv1: incorrect password length (%lu)\n",
(unsigned long)nt_response->length));
return False;
}
SMBOWFencrypt(part_passwd, sec_blob->data, p24);
if (user_sess_key != NULL) {
*user_sess_key = data_blob(NULL, 16);
SMBsesskeygen_ntv1(part_passwd, NULL, user_sess_key->data);
}
#ifdef DEBUG_PASSWORD
DEBUG(100,("Part password (P16) was |\n"));
dump_data(100, (const char *)part_passwd, 16);
DEBUGADD(100,("Password from client was |\n"));
dump_data(100, (const char *)nt_response->data, nt_response->length);
DEBUGADD(100,("Given challenge was |\n"));
dump_data(100, (const char *)sec_blob->data, sec_blob->length);
DEBUGADD(100,("Value from encryption was |\n"));
dump_data(100, (const char *)p24, 24);
#endif
return (memcmp(p24, nt_response->data, 24) == 0);
}
/****************************************************************************
Core of smb password checking routine. (NTLMv2, LMv2)
Note: The same code works with both NTLMv2 and LMv2.
****************************************************************************/
static BOOL smb_pwd_check_ntlmv2(const DATA_BLOB *ntv2_response,
const uchar *part_passwd,
const DATA_BLOB *sec_blob,
const char *user, const char *domain,
BOOL upper_case_domain, /* should the domain be transformed into upper case? */
DATA_BLOB *user_sess_key)
{
/* Finish the encryption of part_passwd. */
uchar kr[16];
uchar value_from_encryption[16];
uchar client_response[16];
DATA_BLOB client_key_data;
BOOL res;
if (part_passwd == NULL) {
DEBUG(10,("No password set - DISALLOWING access\n"));
/* No password set - always False */
return False;
}
if (sec_blob->length != 8) {
DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect challenge size (%lu)\n",
(unsigned long)sec_blob->length));
return False;
}
if (ntv2_response->length < 24) {
/* We MUST have more than 16 bytes, or the stuff below will go
crazy. No known implementation sends less than the 24 bytes
for LMv2, let alone NTLMv2. */
DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect password length (%lu)\n",
(unsigned long)ntv2_response->length));
return False;
}
client_key_data = data_blob(ntv2_response->data+16, ntv2_response->length-16);
/*
todo: should we be checking this for anything? We can't for LMv2,
but for NTLMv2 it is meant to contain the current time etc.
*/
memcpy(client_response, ntv2_response->data, sizeof(client_response));
if (!ntv2_owf_gen(part_passwd, user, domain, upper_case_domain, kr)) {
return False;
}
SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
if (user_sess_key != NULL) {
*user_sess_key = data_blob(NULL, 16);
SMBsesskeygen_ntv2(kr, value_from_encryption, user_sess_key->data);
}
#if DEBUG_PASSWORD
DEBUG(100,("Part password (P16) was |\n"));
dump_data(100, (const char *)part_passwd, 16);
DEBUGADD(100,("Password from client was |\n"));
dump_data(100, (const char *)ntv2_response->data, ntv2_response->length);
DEBUGADD(100,("Variable data from client was |\n"));
dump_data(100, (const char *)client_key_data.data, client_key_data.length);
DEBUGADD(100,("Given challenge was |\n"));
dump_data(100, (const char *)sec_blob->data, sec_blob->length);
DEBUGADD(100,("Value from encryption was |\n"));
dump_data(100, (const char *)value_from_encryption, 16);
#endif
data_blob_clear_free(&client_key_data);
res = (memcmp(value_from_encryption, client_response, 16) == 0);
if ((!res) && (user_sess_key != NULL))
data_blob_clear_free(user_sess_key);
return res;
}
/**
* Check a challenge-response password against the value of the NT or
* LM password hash.
*
* @param mem_ctx talloc context
* @param challenge 8-byte challenge. If all zero, forces plaintext comparison
* @param nt_response 'unicode' NT response to the challenge, or unicode password
* @param lm_response ASCII or LANMAN response to the challenge, or password in DOS code page
* @param username internal Samba username, for log messages
* @param client_username username the client used
* @param client_domain domain name the client used (may be mapped)
* @param nt_pw MD4 unicode password from our passdb or similar
* @param lm_pw LANMAN ASCII password from our passdb or similar
* @param user_sess_key User session key
* @param lm_sess_key LM session key (first 8 bytes of the LM hash)
*/
NTSTATUS ntlm_password_check(TALLOC_CTX *mem_ctx,
const DATA_BLOB *challenge,
const DATA_BLOB *lm_response,
const DATA_BLOB *nt_response,
const DATA_BLOB *lm_interactive_pwd,
const DATA_BLOB *nt_interactive_pwd,
const char *username,
const char *client_username,
const char *client_domain,
const uint8 *lm_pw, const uint8 *nt_pw,
DATA_BLOB *user_sess_key,
DATA_BLOB *lm_sess_key)
{
static const unsigned char zeros[8] = { 0, };
if (nt_pw == NULL) {
DEBUG(3,("ntlm_password_check: NO NT password stored for user %s.\n",
username));
}
if (nt_interactive_pwd && nt_interactive_pwd->length && nt_pw) {
if (nt_interactive_pwd->length != 16) {
DEBUG(3,("ntlm_password_check: Interactive logon: Invalid NT password length (%d) supplied for user %s\n", (int)nt_interactive_pwd->length,
username));
return NT_STATUS_WRONG_PASSWORD;
}
if (memcmp(nt_interactive_pwd->data, nt_pw, 16) == 0) {
if (user_sess_key) {
*user_sess_key = data_blob(NULL, 16);
SMBsesskeygen_ntv1(nt_pw, NULL, user_sess_key->data);
}
return NT_STATUS_OK;
} else {
DEBUG(3,("ntlm_password_check: Interactive logon: NT password check failed for user %s\n",
username));
return NT_STATUS_WRONG_PASSWORD;
}
} else if (lm_interactive_pwd && lm_interactive_pwd->length && lm_pw) {
if (lm_interactive_pwd->length != 16) {
DEBUG(3,("ntlm_password_check: Interactive logon: Invalid LANMAN password length (%d) supplied for user %s\n", (int)lm_interactive_pwd->length,
username));
return NT_STATUS_WRONG_PASSWORD;
}
if (!lp_lanman_auth()) {
DEBUG(3,("ntlm_password_check: Interactive logon: only LANMAN password supplied for user %s, and LM passwords are disabled!\n",
username));
return NT_STATUS_WRONG_PASSWORD;
}
if (memcmp(lm_interactive_pwd->data, lm_pw, 16) == 0) {
return NT_STATUS_OK;
} else {
DEBUG(3,("ntlm_password_check: Interactive logon: LANMAN password check failed for user %s\n",
username));
return NT_STATUS_WRONG_PASSWORD;
}
}
/* Check for cleartext netlogon. Used by Exchange 5.5. */
if (challenge->length == sizeof(zeros) &&
(memcmp(challenge->data, zeros, challenge->length) == 0 )) {
DEBUG(4,("ntlm_password_check: checking plaintext passwords for user %s\n",
username));
if (nt_pw && nt_response->length) {
unsigned char pwhash[16];
mdfour(pwhash, nt_response->data, nt_response->length);
if (memcmp(pwhash, nt_pw, sizeof(pwhash)) == 0) {
return NT_STATUS_OK;
} else {
DEBUG(3,("ntlm_password_check: NT (Unicode) plaintext password check failed for user %s\n",
username));
return NT_STATUS_WRONG_PASSWORD;
}
} else if (!lp_lanman_auth()) {
DEBUG(3,("ntlm_password_check: (plaintext password check) LANMAN passwords NOT PERMITTED for user %s\n",
username));
} else if (lm_pw && lm_response->length) {
uchar dospwd[14];
uchar p16[16];
ZERO_STRUCT(dospwd);
memcpy(dospwd, lm_response->data, MIN(lm_response->length, sizeof(dospwd)));
/* Only the fisrt 14 chars are considered, password need not be null terminated. */
/* we *might* need to upper-case the string here */
E_P16((const unsigned char *)dospwd, p16);
if (memcmp(p16, lm_pw, sizeof(p16)) == 0) {
return NT_STATUS_OK;
} else {
DEBUG(3,("ntlm_password_check: LANMAN (ASCII) plaintext password check failed for user %s\n",
username));
return NT_STATUS_WRONG_PASSWORD;
}
} else {
DEBUG(3, ("Plaintext authentication for user %s attempted, but neither NT nor LM passwords available\n", username));
return NT_STATUS_WRONG_PASSWORD;
}
}
if (nt_response->length != 0 && nt_response->length < 24) {
DEBUG(2,("ntlm_password_check: invalid NT password length (%lu) for user %s\n",
(unsigned long)nt_response->length, username));
}
if (nt_response->length >= 24 && nt_pw) {
if (nt_response->length > 24) {
/* We have the NT MD4 hash challenge available - see if we can
use it
*/
DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with domain [%s]\n", client_domain));
if (smb_pwd_check_ntlmv2( nt_response,
nt_pw, challenge,
client_username,
client_domain,
False,
user_sess_key)) {
return NT_STATUS_OK;
}
DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with uppercased version of domain [%s]\n", client_domain));
if (smb_pwd_check_ntlmv2( nt_response,
nt_pw, challenge,
client_username,
client_domain,
True,
user_sess_key)) {
return NT_STATUS_OK;
}
DEBUG(4,("ntlm_password_check: Checking NTLMv2 password without a domain\n"));
if (smb_pwd_check_ntlmv2( nt_response,
nt_pw, challenge,
client_username,
"",
False,
user_sess_key)) {
return NT_STATUS_OK;
} else {
DEBUG(3,("ntlm_password_check: NTLMv2 password check failed\n"));
return NT_STATUS_WRONG_PASSWORD;
}
}
if (lp_ntlm_auth()) {
/* We have the NT MD4 hash challenge available - see if we can
use it (ie. does it exist in the smbpasswd file).
*/
DEBUG(4,("ntlm_password_check: Checking NT MD4 password\n"));
if (smb_pwd_check_ntlmv1(nt_response,
nt_pw, challenge,
user_sess_key)) {
/* The LM session key for this response is not very secure,
so use it only if we otherwise allow LM authentication */
if (lp_lanman_auth() && lm_pw) {
uint8 first_8_lm_hash[16];
memcpy(first_8_lm_hash, lm_pw, 8);
memset(first_8_lm_hash + 8, '\0', 8);
if (lm_sess_key) {
*lm_sess_key = data_blob(first_8_lm_hash, 16);
}
}
return NT_STATUS_OK;
} else {
DEBUG(3,("ntlm_password_check: NT MD4 password check failed for user %s\n",
username));
return NT_STATUS_WRONG_PASSWORD;
}
} else {
DEBUG(2,("ntlm_password_check: NTLMv1 passwords NOT PERMITTED for user %s\n",
username));
/* no return, becouse we might pick up LMv2 in the LM field */
}
}
if (lm_response->length == 0) {
DEBUG(3,("ntlm_password_check: NEITHER LanMan nor NT password supplied for user %s\n",
username));
return NT_STATUS_WRONG_PASSWORD;
}
if (lm_response->length < 24) {
DEBUG(2,("ntlm_password_check: invalid LanMan password length (%lu) for user %s\n",
(unsigned long)nt_response->length, username));
return NT_STATUS_WRONG_PASSWORD;
}
if (!lp_lanman_auth()) {
DEBUG(3,("ntlm_password_check: Lanman passwords NOT PERMITTED for user %s\n",
username));
} else if (!lm_pw) {
DEBUG(3,("ntlm_password_check: NO LanMan password set for user %s (and no NT password supplied)\n",
username));
} else {
DEBUG(4,("ntlm_password_check: Checking LM password\n"));
if (smb_pwd_check_ntlmv1(lm_response,
lm_pw, challenge,
NULL)) {
uint8 first_8_lm_hash[16];
memcpy(first_8_lm_hash, lm_pw, 8);
memset(first_8_lm_hash + 8, '\0', 8);
if (user_sess_key) {
*user_sess_key = data_blob(first_8_lm_hash, 16);
}
if (lm_sess_key) {
*lm_sess_key = data_blob(first_8_lm_hash, 16);
}
return NT_STATUS_OK;
}
}
if (!nt_pw) {
DEBUG(4,("ntlm_password_check: LM password check failed for user, no NT password %s\n",username));
return NT_STATUS_WRONG_PASSWORD;
}
/* This is for 'LMv2' authentication. almost NTLMv2 but limited to 24 bytes.
- related to Win9X, legacy NAS pass-though authentication
*/
DEBUG(4,("ntlm_password_check: Checking LMv2 password with domain %s\n", client_domain));
if (smb_pwd_check_ntlmv2( lm_response,
nt_pw, challenge,
client_username,
client_domain,
False,
NULL)) {
return NT_STATUS_OK;
}
DEBUG(4,("ntlm_password_check: Checking LMv2 password with upper-cased version of domain %s\n", client_domain));
if (smb_pwd_check_ntlmv2( lm_response,
nt_pw, challenge,
client_username,
client_domain,
True,
NULL)) {
return NT_STATUS_OK;
}
DEBUG(4,("ntlm_password_check: Checking LMv2 password without a domain\n"));
if (smb_pwd_check_ntlmv2( lm_response,
nt_pw, challenge,
client_username,
"",
False,
NULL)) {
return NT_STATUS_OK;
}
/* Apparently NT accepts NT responses in the LM field
- I think this is related to Win9X pass-though authentication
*/
DEBUG(4,("ntlm_password_check: Checking NT MD4 password in LM field\n"));
if (lp_ntlm_auth()) {
if (smb_pwd_check_ntlmv1(lm_response,
nt_pw, challenge,
NULL)) {
/* The session key for this response is still very odd.
It not very secure, so use it only if we otherwise
allow LM authentication */
if (lp_lanman_auth() && lm_pw) {
uint8 first_8_lm_hash[16];
memcpy(first_8_lm_hash, lm_pw, 8);
memset(first_8_lm_hash + 8, '\0', 8);
if (user_sess_key) {
*user_sess_key = data_blob(first_8_lm_hash, 16);
}
if (lm_sess_key) {
*lm_sess_key = data_blob(first_8_lm_hash, 16);
}
}
return NT_STATUS_OK;
}
DEBUG(3,("ntlm_password_check: LM password, NT MD4 password in LM field and LMv2 failed for user %s\n",username));
} else {
DEBUG(3,("ntlm_password_check: LM password and LMv2 failed for user %s, and NT MD4 password in LM field not permitted\n",username));
}
return NT_STATUS_WRONG_PASSWORD;
}
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