Line data    Source code

       1             : /*
       2             :    Unix SMB/CIFS implementation.
       3             :    Wrapper for gnutls hash and encryption functions
       4             : 
       5             :    Copyright (C) Stefan Metzmacher <metze@samba.org> 2007
       6             :    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2009-2019
       7             :    Copyright (c) Andreas Schneider <asn@samba.org> 2019
       8             : 
       9             :    This program is free software; you can redistribute it and/or modify
      10             :    it under the terms of the GNU General Public License as published by
      11             :    the Free Software Foundation; either version 3 of the License, or
      12             :    (at your option) any later version.
      13             : 
      14             :    This program is distributed in the hope that it will be useful,
      15             :    but WITHOUT ANY WARRANTY; without even the implied warranty of
      16             :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      17             :    GNU General Public License for more details.
      18             : 
      19             :    You should have received a copy of the GNU General Public License
      20             :    along with this program.  If not, see <http://www.gnu.org/licenses/>.
      21             : 
      22             : */
      23             : 
      24             : /*
      25             :  * This (arcfour over data with a key combined from two imputs, one
      26             :  * the key another the confounder), is a common pattern in pre-AES
      27             :  * windows cryptography
      28             :  *
      29             :  * Some protocols put the confounder first, others second so both
      30             :  * parameters are named key_input here.
      31             :  *
      32             :  */
      33             : 
      34             : #include "includes.h"
      35             : #include "lib/util/data_blob.h"
      36             : #include <gnutls/gnutls.h>
      37             : #include <gnutls/crypto.h>
      38             : #include "gnutls_helpers.h"
      39             : #include "lib/util/memory.h"
      40             : 
      41       12872 : int samba_gnutls_arcfour_confounded_md5(const DATA_BLOB *key_input1,
      42             :                                         const DATA_BLOB *key_input2,
      43             :                                         DATA_BLOB *data,
      44             :                                         enum samba_gnutls_direction encrypt)
      45             : {
      46             :         int rc;
      47       12872 :         gnutls_hash_hd_t hash_hnd = NULL;
      48             :         uint8_t confounded_key[16];
      49       12872 :         gnutls_cipher_hd_t cipher_hnd = NULL;
      50       12872 :         gnutls_datum_t confounded_key_datum = {
      51             :                 .data = confounded_key,
      52             :                 .size = sizeof(confounded_key),
      53             :         };
      54             : 
      55       12872 :         rc = gnutls_hash_init(&hash_hnd, GNUTLS_DIG_MD5);
      56       12872 :         if (rc < 0) {
      57           0 :                 return rc;
      58             :         }
      59       12872 :         rc = gnutls_hash(hash_hnd, key_input1->data, key_input1->length);
      60       12872 :         if (rc < 0) {
      61           0 :                 gnutls_hash_deinit(hash_hnd, NULL);
      62           0 :                 return rc;
      63             :         }
      64       12872 :         rc = gnutls_hash(hash_hnd, key_input2->data, key_input2->length);
      65       12872 :         if (rc < 0) {
      66           0 :                 gnutls_hash_deinit(hash_hnd, NULL);
      67           0 :                 return rc;
      68             :         }
      69             : 
      70       12872 :         gnutls_hash_deinit(hash_hnd, confounded_key);
      71             : 
      72       12872 :         rc = gnutls_cipher_init(&cipher_hnd,
      73             :                                 GNUTLS_CIPHER_ARCFOUR_128,
      74             :                                 &confounded_key_datum,
      75             :                                 NULL);
      76       12872 :         if (rc < 0) {
      77           0 :                 return rc;
      78             :         }
      79             : 
      80       12872 :         if (encrypt == SAMBA_GNUTLS_ENCRYPT) {
      81       13463 :                 rc = gnutls_cipher_encrypt(cipher_hnd,
      82        6915 :                                            data->data,
      83             :                                            data->length);
      84             :         } else {
      85       11641 :                 rc = gnutls_cipher_decrypt(cipher_hnd,
      86        5957 :                                            data->data,
      87             :                                            data->length);
      88             :         }
      89       12872 :         gnutls_cipher_deinit(cipher_hnd);
      90       12872 :         ZERO_ARRAY(confounded_key);
      91             : 
      92       12872 :         return rc;
      93             : }