mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-25 02:09:42 +00:00
![Giel van Schijndel](/assets/img/avatar_default.png)
When leaving a function use memzero_explicit instead of memset(0) to clear stack allocated buffers. memset(0) may be optimized away. This particular buffer is highly likely to contain sensitive data which we shouldn't leak (it's named 'passwd' after all). Signed-off-by: Giel van Schijndel <me@mortis.eu> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Reported-at: http://www.viva64.com/en/b/0299/ Reported-by: Andrey Karpov Reported-by: Svyatoslav Razmyslov Signed-off-by: Steve French <steve.french@primarydata.com>
249 lines
6 KiB
C
249 lines
6 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_fs_sb.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);
|
|
cifs_dbg(VFS, "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)
|
|
cifs_dbg(VFS, "could not encrypt crypt key rc: %d\n", rc);
|
|
|
|
crypto_free_blkcipher(tfm_des);
|
|
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);
|
|
cifs_dbg(VFS, "%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;
|
|
goto mdfour_err;
|
|
}
|
|
sdescmd4->shash.tfm = md4;
|
|
sdescmd4->shash.flags = 0x0;
|
|
|
|
rc = crypto_shash_init(&sdescmd4->shash);
|
|
if (rc) {
|
|
cifs_dbg(VFS, "%s: Could not init md4 shash\n", __func__);
|
|
goto mdfour_err;
|
|
}
|
|
rc = crypto_shash_update(&sdescmd4->shash, link_str, link_len);
|
|
if (rc) {
|
|
cifs_dbg(VFS, "%s: Could not update with link_str\n", __func__);
|
|
goto mdfour_err;
|
|
}
|
|
rc = crypto_shash_final(&sdescmd4->shash, md4_hash);
|
|
if (rc)
|
|
cifs_dbg(VFS, "%s: Could not generate md4 hash\n", __func__);
|
|
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* Creates the MD4 Hash of the users password in NT UNICODE.
|
|
*/
|
|
|
|
int
|
|
E_md4hash(const unsigned char *passwd, unsigned char *p16,
|
|
const struct nls_table *codepage)
|
|
{
|
|
int rc;
|
|
int len;
|
|
__le16 wpwd[129];
|
|
|
|
/* Password cannot be longer than 128 characters */
|
|
if (passwd) /* Password must be converted to NT unicode */
|
|
len = cifs_strtoUTF16(wpwd, passwd, 128, codepage);
|
|
else {
|
|
len = 0;
|
|
*wpwd = 0; /* Ensure string is null terminated */
|
|
}
|
|
|
|
rc = mdfour(p16, (unsigned char *) wpwd, len * sizeof(__le16));
|
|
memzero_explicit(wpwd, sizeof(wpwd));
|
|
|
|
return rc;
|
|
}
|
|
|
|
/* Does the NT MD4 hash then des encryption. */
|
|
int
|
|
SMBNTencrypt(unsigned char *passwd, unsigned char *c8, unsigned char *p24,
|
|
const struct nls_table *codepage)
|
|
{
|
|
int rc;
|
|
unsigned char p16[16], p21[21];
|
|
|
|
memset(p16, '\0', 16);
|
|
memset(p21, '\0', 21);
|
|
|
|
rc = E_md4hash(passwd, p16, codepage);
|
|
if (rc) {
|
|
cifs_dbg(FYI, "%s Can't generate NT hash, error: %d\n",
|
|
__func__, rc);
|
|
return rc;
|
|
}
|
|
memcpy(p21, p16, 16);
|
|
rc = E_P24(p21, c8, p24);
|
|
return rc;
|
|
}
|