linux/fs/cifs/smbencrypt.c
Steve French 43988d7685 [CIFS] Use ecb des kernel crypto APIs instead of
local cifs functions (repost)

Using kernel crypto APIs for DES encryption during LM and NT hash generation
instead of local functions within cifs.
Source file smbdes.c is deleted sans four functions, one of which
uses ecb des functionality provided by kernel crypto APIs.

Remove function SMBOWFencrypt.

Add return codes to various functions such as calc_lanman_hash,
SMBencrypt, and SMBNTencrypt.  Includes fix noticed by Dan Carpenter.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
CC: Dan Carpenter <error27@gmail.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-05-19 14:10:49 +00:00

404 lines
9.7 KiB
C

/*
Unix SMB/Netbios implementation.
Version 1.9.
SMB parameters and setup
Copyright (C) Andrew Tridgell 1992-2000
Copyright (C) Luke Kenneth Casson Leighton 1996-2000
Modified by Jeremy Allison 1995.
Copyright (C) Andrew Bartlett <abartlet@samba.org> 2002-2003
Modified by Steve French (sfrench@us.ibm.com) 2002-2003
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 <linux/module.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/random.h>
#include "cifs_unicode.h"
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifs_debug.h"
#include "cifsproto.h"
#ifndef false
#define false 0
#endif
#ifndef true
#define true 1
#endif
/* following came from the other byteorder.h to avoid include conflicts */
#define CVAL(buf,pos) (((unsigned char *)(buf))[pos])
#define SSVALX(buf,pos,val) (CVAL(buf,pos)=(val)&0xFF,CVAL(buf,pos+1)=(val)>>8)
#define SSVAL(buf,pos,val) SSVALX((buf),(pos),((__u16)(val)))
static void
str_to_key(unsigned char *str, unsigned char *key)
{
int i;
key[0] = str[0] >> 1;
key[1] = ((str[0] & 0x01) << 6) | (str[1] >> 2);
key[2] = ((str[1] & 0x03) << 5) | (str[2] >> 3);
key[3] = ((str[2] & 0x07) << 4) | (str[3] >> 4);
key[4] = ((str[3] & 0x0F) << 3) | (str[4] >> 5);
key[5] = ((str[4] & 0x1F) << 2) | (str[5] >> 6);
key[6] = ((str[5] & 0x3F) << 1) | (str[6] >> 7);
key[7] = str[6] & 0x7F;
for (i = 0; i < 8; i++)
key[i] = (key[i] << 1);
}
static int
smbhash(unsigned char *out, const unsigned char *in, unsigned char *key)
{
int rc;
unsigned char key2[8];
struct crypto_blkcipher *tfm_des;
struct scatterlist sgin, sgout;
struct blkcipher_desc desc;
str_to_key(key, key2);
tfm_des = crypto_alloc_blkcipher("ecb(des)", 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(tfm_des)) {
rc = PTR_ERR(tfm_des);
cERROR(1, "could not allocate des crypto API\n");
goto smbhash_err;
}
desc.tfm = tfm_des;
crypto_blkcipher_setkey(tfm_des, key2, 8);
sg_init_one(&sgin, in, 8);
sg_init_one(&sgout, out, 8);
rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, 8);
if (rc) {
cERROR(1, "could not encrypt crypt key rc: %d\n", rc);
crypto_free_blkcipher(tfm_des);
goto smbhash_err;
}
smbhash_err:
return rc;
}
static int
E_P16(unsigned char *p14, unsigned char *p16)
{
int rc;
unsigned char sp8[8] =
{ 0x4b, 0x47, 0x53, 0x21, 0x40, 0x23, 0x24, 0x25 };
rc = smbhash(p16, sp8, p14);
if (rc)
return rc;
rc = smbhash(p16 + 8, sp8, p14 + 7);
return rc;
}
static int
E_P24(unsigned char *p21, const unsigned char *c8, unsigned char *p24)
{
int rc;
rc = smbhash(p24, c8, p21);
if (rc)
return rc;
rc = smbhash(p24 + 8, c8, p21 + 7);
if (rc)
return rc;
rc = smbhash(p24 + 16, c8, p21 + 14);
return rc;
}
/* produce a md4 message digest from data of length n bytes */
int
mdfour(unsigned char *md4_hash, unsigned char *link_str, int link_len)
{
int rc;
unsigned int size;
struct crypto_shash *md4;
struct sdesc *sdescmd4;
md4 = crypto_alloc_shash("md4", 0, 0);
if (IS_ERR(md4)) {
rc = PTR_ERR(md4);
cERROR(1, "%s: Crypto md4 allocation error %d\n", __func__, rc);
return rc;
}
size = sizeof(struct shash_desc) + crypto_shash_descsize(md4);
sdescmd4 = kmalloc(size, GFP_KERNEL);
if (!sdescmd4) {
rc = -ENOMEM;
cERROR(1, "%s: Memory allocation failure\n", __func__);
goto mdfour_err;
}
sdescmd4->shash.tfm = md4;
sdescmd4->shash.flags = 0x0;
rc = crypto_shash_init(&sdescmd4->shash);
if (rc) {
cERROR(1, "%s: Could not init md4 shash\n", __func__);
goto mdfour_err;
}
crypto_shash_update(&sdescmd4->shash, link_str, link_len);
rc = crypto_shash_final(&sdescmd4->shash, md4_hash);
mdfour_err:
crypto_free_shash(md4);
kfree(sdescmd4);
return rc;
}
/*
This implements the X/Open SMB password encryption
It takes a password, a 8 byte "crypt key" and puts 24 bytes of
encrypted password into p24 */
/* Note that password must be uppercased and null terminated */
int
SMBencrypt(unsigned char *passwd, const unsigned char *c8, unsigned char *p24)
{
int rc;
unsigned char p14[14], p16[16], p21[21];
memset(p14, '\0', 14);
memset(p16, '\0', 16);
memset(p21, '\0', 21);
memcpy(p14, passwd, 14);
rc = E_P16(p14, p16);
if (rc)
return rc;
memcpy(p21, p16, 16);
rc = E_P24(p21, c8, p24);
return rc;
}
/* Routines for Windows NT MD4 Hash functions. */
static int
_my_wcslen(__u16 *str)
{
int len = 0;
while (*str++ != 0)
len++;
return len;
}
/*
* Convert a string into an NT UNICODE string.
* Note that regardless of processor type
* this must be in intel (little-endian)
* format.
*/
static int
_my_mbstowcs(__u16 *dst, const unsigned char *src, int len)
{ /* BB not a very good conversion routine - change/fix */
int i;
__u16 val;
for (i = 0; i < len; i++) {
val = *src;
SSVAL(dst, 0, val);
dst++;
src++;
if (val == 0)
break;
}
return i;
}
/*
* Creates the MD4 Hash of the users password in NT UNICODE.
*/
int
E_md4hash(const unsigned char *passwd, unsigned char *p16)
{
int rc;
int len;
__u16 wpwd[129];
/* Password cannot be longer than 128 characters */
if (passwd) {
len = strlen((char *) passwd);
if (len > 128)
len = 128;
/* Password must be converted to NT unicode */
_my_mbstowcs(wpwd, passwd, len);
} else
len = 0;
wpwd[len] = 0; /* Ensure string is null terminated */
/* Calculate length in bytes */
len = _my_wcslen(wpwd) * sizeof(__u16);
rc = mdfour(p16, (unsigned char *) wpwd, len);
memset(wpwd, 0, 129 * 2);
return rc;
}
#if 0 /* currently unused */
/* Does both the NT and LM owfs of a user's password */
static void
nt_lm_owf_gen(char *pwd, unsigned char nt_p16[16], unsigned char p16[16])
{
char passwd[514];
memset(passwd, '\0', 514);
if (strlen(pwd) < 513)
strcpy(passwd, pwd);
else
memcpy(passwd, pwd, 512);
/* Calculate the MD4 hash (NT compatible) of the password */
memset(nt_p16, '\0', 16);
E_md4hash(passwd, nt_p16);
/* Mangle the passwords into Lanman format */
passwd[14] = '\0';
/* strupper(passwd); */
/* Calculate the SMB (lanman) hash functions of the password */
memset(p16, '\0', 16);
E_P16((unsigned char *) passwd, (unsigned char *) p16);
/* clear out local copy of user's password (just being paranoid). */
memset(passwd, '\0', sizeof(passwd));
}
#endif
/* Does the NTLMv2 owfs of a user's password */
#if 0 /* function not needed yet - but will be soon */
static void
ntv2_owf_gen(const unsigned char owf[16], const char *user_n,
const char *domain_n, unsigned char kr_buf[16],
const struct nls_table *nls_codepage)
{
wchar_t *user_u;
wchar_t *dom_u;
int user_l, domain_l;
struct HMACMD5Context ctx;
/* might as well do one alloc to hold both (user_u and dom_u) */
user_u = kmalloc(2048 * sizeof(wchar_t), GFP_KERNEL);
if (user_u == NULL)
return;
dom_u = user_u + 1024;
/* push_ucs2(NULL, user_u, user_n, (user_l+1)*2,
STR_UNICODE|STR_NOALIGN|STR_TERMINATE|STR_UPPER);
push_ucs2(NULL, dom_u, domain_n, (domain_l+1)*2,
STR_UNICODE|STR_NOALIGN|STR_TERMINATE|STR_UPPER); */
/* BB user and domain may need to be uppercased */
user_l = cifs_strtoUCS(user_u, user_n, 511, nls_codepage);
domain_l = cifs_strtoUCS(dom_u, domain_n, 511, nls_codepage);
user_l++; /* trailing null */
domain_l++;
hmac_md5_init_limK_to_64(owf, 16, &ctx);
hmac_md5_update((const unsigned char *) user_u, user_l * 2, &ctx);
hmac_md5_update((const unsigned char *) dom_u, domain_l * 2, &ctx);
hmac_md5_final(kr_buf, &ctx);
kfree(user_u);
}
#endif
/* Does the des encryption from the FIRST 8 BYTES of the NT or LM MD4 hash. */
#if 0 /* currently unused */
static void
NTLMSSPOWFencrypt(unsigned char passwd[8],
unsigned char *ntlmchalresp, unsigned char p24[24])
{
unsigned char p21[21];
memset(p21, '\0', 21);
memcpy(p21, passwd, 8);
memset(p21 + 8, 0xbd, 8);
E_P24(p21, ntlmchalresp, p24);
}
#endif
/* Does the NT MD4 hash then des encryption. */
int
SMBNTencrypt(unsigned char *passwd, unsigned char *c8, unsigned char *p24)
{
int rc;
unsigned char p16[16], p21[21];
memset(p16, '\0', 16);
memset(p21, '\0', 21);
rc = E_md4hash(passwd, p16);
if (rc) {
cFYI(1, "%s Can't generate NT hash, error: %d", __func__, rc);
return rc;
}
memcpy(p21, p16, 16);
rc = E_P24(p21, c8, p24);
return rc;
}
/* Does the md5 encryption from the NT hash for NTLMv2. */
/* These routines will be needed later */
#if 0
static void
SMBOWFencrypt_ntv2(const unsigned char kr[16],
const struct data_blob *srv_chal,
const struct data_blob *cli_chal, unsigned char resp_buf[16])
{
struct HMACMD5Context ctx;
hmac_md5_init_limK_to_64(kr, 16, &ctx);
hmac_md5_update(srv_chal->data, srv_chal->length, &ctx);
hmac_md5_update(cli_chal->data, cli_chal->length, &ctx);
hmac_md5_final(resp_buf, &ctx);
}
static void
SMBsesskeygen_ntv2(const unsigned char kr[16],
const unsigned char *nt_resp, __u8 sess_key[16])
{
struct HMACMD5Context ctx;
hmac_md5_init_limK_to_64(kr, 16, &ctx);
hmac_md5_update(nt_resp, 16, &ctx);
hmac_md5_final((unsigned char *) sess_key, &ctx);
}
static void
SMBsesskeygen_ntv1(const unsigned char kr[16],
const unsigned char *nt_resp, __u8 sess_key[16])
{
mdfour((unsigned char *) sess_key, (unsigned char *) kr, 16);
}
#endif