1 /* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */

     2 /* lib/crypto/openssl/enc_provider/des.c */

     3 /*

     4  * Copyright (C) 2009 by the Massachusetts Institute of Technology.

     5  * All rights reserved.

     6  *

     7  * Export of this software from the United States of America may

     8  *   require a specific license from the United States Government.

     9  *   It is the responsibility of any person or organization contemplating

    10  *   export to obtain such a license before exporting.

    11  *

    12  * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and

    13  * distribute this software and its documentation for any purpose and

    14  * without fee is hereby granted, provided that the above copyright

    15  * notice appear in all copies and that both that copyright notice and

    16  * this permission notice appear in supporting documentation, and that

    17  * the name of M.I.T. not be used in advertising or publicity pertaining

    18  * to distribution of the software without specific, written prior

    19  * permission.  Furthermore if you modify this software you must label

    20  * your software as modified software and not distribute it in such a

    21  * fashion that it might be confused with the original M.I.T. software.

    22  * M.I.T. makes no representations about the suitability of

    23  * this software for any purpose.  It is provided "as is" without express

    24  * or implied warranty.

    25  */

    26 

    27 /*

    28  * Copyright (C) 1998 by the FundsXpress, INC.

    29  *

    30  * All rights reserved.

    31  *

    32  * Export of this software from the United States of America may require

    33  * a specific license from the United States Government.  It is the

    34  * responsibility of any person or organization contemplating export to

    35  * obtain such a license before exporting.

    36  *

    37  * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and

    38  * distribute this software and its documentation for any purpose and

    39  * without fee is hereby granted, provided that the above copyright

    40  * notice appear in all copies and that both that copyright notice and

    41  * this permission notice appear in supporting documentation, and that

    42  * the name of FundsXpress. not be used in advertising or publicity pertaining

    43  * to distribution of the software without specific, written prior

    44  * permission.  FundsXpress makes no representations about the suitability of

    45  * this software for any purpose.  It is provided "as is" without express

    46  * or implied warranty.

    47  *

    48  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR

    49  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED

    50  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.

    51  */

    52 /*

    53  * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.

    54  */

    55 

    56 #include "crypto_int.h"

    57 #include <libucrypto.h>

    58 

    59 #define DES_BLOCK_SIZE 8

    60 #define DES_KEY_SIZE 8

    61 #define DES_KEY_BYTES 7

    62 

    63 static krb5_error_code

    64 validate(krb5_key key, const krb5_data *ivec, const krb5_crypto_iov *data,

    65          size_t num_data, size_t *inlen)

    66 {

    67     size_t input_length = iov_total_length(data, num_data, FALSE);

    68 

    69     if (key->keyblock.length != DES_KEY_SIZE)

    70         return KRB5_BAD_KEYSIZE;

    71     if ((input_length % DES_BLOCK_SIZE) != 0)

    72         return KRB5_BAD_MSIZE;

    73     if (ivec && (ivec->length != DES_BLOCK_SIZE))

    74         return KRB5_BAD_MSIZE;

    75 

    76     if (inlen != NULL)

    77         *inlen = input_length;

    78 

    79     return 0;

    80 }

    81 

    82 static krb5_error_code

    83 k5_des_encrypt(krb5_key key, const krb5_data *ivec, krb5_crypto_iov *data,

    84                size_t num_data)

    85 {

    86     int ret;

    87     size_t  olen, dlen;

    88     uchar_t *obuf, *dbuf;

    89     uchar_t tmp_iv[DES_BLOCK_SIZE];

    90     struct iov_cursor cursor;

    91 

    92     ret = validate(key, ivec, data, num_data, &dlen);

    93     if (ret != 0 || dlen == 0)

    94         return ret;

    95 

    96     if (ivec && ivec->data)

    97         memcpy(tmp_iv, ivec->data, ivec->length);

    98     else

    99         memset(tmp_iv, 0, sizeof(tmp_iv));

   100 

   101     olen = dlen;

   102     obuf = malloc(olen);

   103     if (!obuf)

   104         return ENOMEM;

   105 

   106     dbuf = malloc(dlen);

   107     if (!dbuf){

   108         free(obuf);

   109         return ENOMEM;

   110     }

   111 

   112     /* Init iov cursor to gather data for encypting (FALSE) */

   113     k5_iov_cursor_init(&cursor, data, num_data, dlen, FALSE);

   114     /* Get all that data into dbuf */

   115     k5_iov_cursor_get(&cursor, dbuf);

   116 

   117     if (ucrypto_encrypt(CRYPTO_DES_CBC,

   118                         key->keyblock.contents,

   119                         key->keyblock.length,

   120                         tmp_iv, sizeof(tmp_iv),

   121                         dbuf, dlen, obuf, &olen) != CRYPTO_SUCCESS) {

   122         ret = KRB5_CRYPTO_INTERNAL;

   123     } else {

   124         k5_iov_cursor_put(&cursor, obuf);

   125     }

   126 

   127     /*

   128      * Updating the ivec arg, if present because of an old/obscure concept of

   129      * cipher state that is being used by only BSD rlogin.  See RFCs 1391 and

   130      * 1392 in regards to the vague description of cipher state.

   131      */

   132     if (!ret && ivec && ivec->data) {

   133         /* Copy last block of cipher text output */

   134         memcpy(ivec->data, obuf + (dlen - DES_BLOCK_SIZE), DES_BLOCK_SIZE);

   135     }

   136 

   137     zapfree(obuf, olen);

   138     zapfree(dbuf, dlen);

   139 

   140     return ret;

   141 }

   142 

   143 static krb5_error_code

   144 k5_des_decrypt(krb5_key key, const krb5_data *ivec, krb5_crypto_iov *data,

   145                size_t num_data)

   146 {

   147     int ret;

   148     size_t  olen, dlen;

   149     uchar_t *obuf, *dbuf;

   150     uchar_t tmp_iv[DES_BLOCK_SIZE];

   151     struct iov_cursor cursor;

   152 

   153     ret = validate(key, ivec, data, num_data, &dlen);

   154     if (ret != 0 || dlen == 0)

   155         return ret;

   156 

   157     if (ivec && ivec->data)

   158         memcpy(tmp_iv, ivec->data, ivec->length);

   159     else

   160         memset(tmp_iv, 0, sizeof(tmp_iv));

   161 

   162     olen = dlen;

   163     obuf = malloc(olen);

   164     if (!obuf)

   165         return ENOMEM;

   166 

   167     dbuf = malloc(dlen);

   168     if (!dbuf){

   169         free(obuf);

   170         return ENOMEM;

   171     }

   172 

   173     /* Init iov cursor to gather cipher text for decrypting (FALSE) */

   174     k5_iov_cursor_init(&cursor, data, num_data, dlen, FALSE);

   175     /* Gather all that cipher text into dbuf */

   176     k5_iov_cursor_get(&cursor, dbuf);

   177 

   178     if (ucrypto_decrypt(CRYPTO_DES_CBC,

   179                         key->keyblock.contents,

   180                         key->keyblock.length,

   181                         tmp_iv, sizeof(tmp_iv),

   182                         dbuf, dlen, obuf, &olen) != CRYPTO_SUCCESS) {

   183         ret = KRB5_CRYPTO_INTERNAL;

   184     } else {

   185         k5_iov_cursor_put(&cursor, obuf);

   186     }

   187 

   188     /*

   189      * Updating the ivec arg, if present because of an old/obscure concept of

   190      * cipher state that is being used by only BSD rlogin.  See RFCs 1391 and

   191      * 1392 in regards to the vague description of cipher state.

   192      */

   193     if (!ret && ivec && ivec->data) {

   194         /* Copy last block of cipher text input */

   195         memcpy(ivec->data, dbuf + (dlen - DES_BLOCK_SIZE), DES_BLOCK_SIZE);

   196     }

   197 

   198     zapfree(obuf, olen);

   199     zapfree(dbuf, dlen);

   200 

   201     return ret;

   202 }

   203 

   204 static krb5_error_code

   205 k5_des_cbc_mac(krb5_key key, const krb5_crypto_iov *data, size_t num_data,

   206                const krb5_data *ivec, krb5_data *output)

   207 {

   208     int ret;

   209     struct iov_cursor cursor;

   210     uchar_t blockY[DES_BLOCK_SIZE], blockB[DES_BLOCK_SIZE];

   211     size_t olen;

   212 

   213     ret = validate(key, ivec, data, num_data, NULL);

   214     if (ret != 0)

   215         return ret;

   216 

   217     if (output->length != DES_BLOCK_SIZE)

   218         return KRB5_BAD_MSIZE;

   219 

   220     if (ivec != NULL)

   221         memcpy(blockY, ivec->data, DES_BLOCK_SIZE);

   222     else

   223         memset(blockY, 0, DES_BLOCK_SIZE);

   224 

   225     k5_iov_cursor_init(&cursor, data, num_data, DES_BLOCK_SIZE, FALSE);

   226     while (k5_iov_cursor_get(&cursor, blockB)) {

   227         store_64_n(load_64_n(blockB) ^ load_64_n(blockY), blockB);

   228         olen = sizeof(blockY);

   229         if (ucrypto_encrypt(CRYPTO_DES_ECB,

   230                             key->keyblock.contents,

   231                             key->keyblock.length,

   232                             NULL, 0,

   233                             blockB, sizeof(blockB),

   234                             blockY, &olen) != CRYPTO_SUCCESS) {

   235             return KRB5_CRYPTO_INTERNAL;

   236         }

   237     }

   238 

   239     memcpy(output->data, blockY, DES_BLOCK_SIZE);

   240     return 0;

   241 }

   242 

   243 const struct krb5_enc_provider krb5int_enc_des = {

   244     DES_BLOCK_SIZE,

   245     DES_KEY_BYTES, DES_KEY_SIZE,

   246     k5_des_encrypt,

   247     k5_des_decrypt,

   248     k5_des_cbc_mac,

   249     krb5int_des_init_state,

   250     krb5int_default_free_state

   251 };