providers/implementations/ciphers/cipher_tdes_wrap.c

   1 /*
   2  * Copyright 1995-2019 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <openssl/sha.h>
  11 #include "cipher_tdes_default.h"
  12 #include "crypto/evp.h"
  13 #include "crypto/rand.h"
  14 #include "prov/implementations.h"
  15 #include "prov/providercommonerr.h"
  16
  17 /* TODO (3.0) Figure out what flags are required */
  18 #define TDES_WRAP_FLAGS (EVP_CIPH_WRAP_MODE | EVP_CIPH_CUSTOM_IV)
  19
  20
  21 static OSSL_OP_cipher_update_fn tdes_wrap_update;
  22 static OSSL_OP_cipher_cipher_fn tdes_wrap_cipher;
  23
  24 static const unsigned char wrap_iv[8] =
  25 {
  26     0x4a, 0xdd, 0xa2, 0x2c, 0x79, 0xe8, 0x21, 0x05
  27 };
  28
  29 static int des_ede3_unwrap(PROV_CIPHER_CTX *ctx, unsigned char *out,
  30                            const unsigned char *in, size_t inl)
  31 {
  32     unsigned char icv[8], iv[TDES_IVLEN], sha1tmp[SHA_DIGEST_LENGTH];
  33     int rv = -1;
  34
  35     if (inl < 24)
  36         return -1;
  37     if (out == NULL)
  38         return inl - 16;
  39
  40     memcpy(ctx->iv, wrap_iv, 8);
  41     /* Decrypt first block which will end up as icv */
  42     ctx->hw->cipher(ctx, icv, in, 8);
  43     /* Decrypt central blocks */
  44     /*
  45      * If decrypting in place move whole output along a block so the next
  46      * des_ede_cbc_cipher is in place.
  47      */
  48     if (out == in) {
  49         memmove(out, out + 8, inl - 8);
  50         in -= 8;
  51     }
  52     ctx->hw->cipher(ctx, out, in + 8, inl - 16);
  53     /* Decrypt final block which will be IV */
  54     ctx->hw->cipher(ctx, iv, in + inl - 8, 8);
  55     /* Reverse order of everything */
  56     BUF_reverse(icv, NULL, 8);
  57     BUF_reverse(out, NULL, inl - 16);
  58     BUF_reverse(ctx->iv, iv, 8);
  59     /* Decrypt again using new IV */
  60     ctx->hw->cipher(ctx, out, out, inl - 16);
  61     ctx->hw->cipher(ctx, icv, icv, 8);
  62     /* Work out SHA1 hash of first portion */
  63     SHA1(out, inl - 16, sha1tmp);
  64
  65     if (!CRYPTO_memcmp(sha1tmp, icv, 8))
  66         rv = inl - 16;
  67     OPENSSL_cleanse(icv, 8);
  68     OPENSSL_cleanse(sha1tmp, SHA_DIGEST_LENGTH);
  69     OPENSSL_cleanse(iv, 8);
  70     OPENSSL_cleanse(ctx->iv, sizeof(ctx->iv));
  71     if (rv == -1)
  72         OPENSSL_cleanse(out, inl - 16);
  73
  74     return rv;
  75 }
  76
  77 static int des_ede3_wrap(PROV_CIPHER_CTX *ctx, unsigned char *out,
  78                          const unsigned char *in, size_t inl)
  79 {
  80     unsigned char sha1tmp[SHA_DIGEST_LENGTH];
  81     size_t ivlen = TDES_IVLEN;
  82     size_t icvlen = TDES_IVLEN;
  83     size_t len = inl + ivlen + icvlen;
  84
  85     if (out == NULL)
  86         return len;
  87
  88     /* Copy input to output buffer + 8 so we have space for IV */
  89     memmove(out + ivlen, in, inl);
  90     /* Work out ICV */
  91     SHA1(in, inl, sha1tmp);
  92     memcpy(out + inl + ivlen, sha1tmp, icvlen);
  93     OPENSSL_cleanse(sha1tmp, SHA_DIGEST_LENGTH);
  94     /* Generate random IV */
  95     if (rand_bytes_ex(ctx->libctx, ctx->iv, ivlen) <= 0)
  96         return 0;
  97     memcpy(out, ctx->iv, ivlen);
  98     /* Encrypt everything after IV in place */
  99     ctx->hw->cipher(ctx, out + ivlen, out + ivlen, inl + ivlen);
 100     BUF_reverse(out, NULL, len);
 101     memcpy(ctx->iv, wrap_iv, ivlen);
 102     ctx->hw->cipher(ctx, out, out, len);
 103     return len;
 104 }
 105
 106 static int tdes_wrap_cipher_internal(PROV_CIPHER_CTX *ctx, unsigned char *out,
 107                                      const unsigned char *in, size_t inl)
 108 {
 109     /*
 110      * Sanity check input length: we typically only wrap keys so EVP_MAXCHUNK
 111      * is more than will ever be needed. Also input length must be a multiple
 112      * of 8 bits.
 113      */
 114     if (inl >= EVP_MAXCHUNK || inl % 8)
 115         return -1;
 116     if (ctx->enc)
 117         return des_ede3_wrap(ctx, out, in, inl);
 118     else
 119         return des_ede3_unwrap(ctx, out, in, inl);
 120 }
 121
 122 static int tdes_wrap_cipher(void *vctx,
 123                             unsigned char *out, size_t *outl, size_t outsize,
 124                             const unsigned char *in, size_t inl)
 125 {
 126     PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
 127     int ret;
 128
 129     *outl = 0;
 130     if (outsize < inl) {
 131         PROVerr(0, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
 132         return 0;
 133     }
 134
 135     ret = tdes_wrap_cipher_internal(ctx, out, in, inl);
 136     if (ret <= 0)
 137         return 0;
 138
 139     *outl = ret;
 140     return 1;
 141 }
 142
 143 static int tdes_wrap_update(void *vctx, unsigned char *out, size_t *outl,
 144                             size_t outsize, const unsigned char *in,
 145                             size_t inl)
 146 {
 147     *outl = 0;
 148     if (inl == 0)
 149         return 1;
 150     if (outsize < inl) {
 151         PROVerr(0, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
 152         return 0;
 153     }
 154
 155     if (!tdes_wrap_cipher(vctx, out, outl, outsize, in, inl)) {
 156         PROVerr(0, PROV_R_CIPHER_OPERATION_FAILED);
 157         return 0;
 158     }
 159     return 1;
 160 }
 161
 162
 163 # define IMPLEMENT_WRAP_CIPHER(flags, kbits, blkbits, ivbits)                  \
 164 static OSSL_OP_cipher_newctx_fn tdes_wrap_newctx;                              \
 165 static void *tdes_wrap_newctx(void *provctx)                                   \
 166 {                                                                              \
 167     return tdes_newctx(provctx, EVP_CIPH_WRAP_MODE, kbits, blkbits, ivbits,    \
 168                        flags, PROV_CIPHER_HW_tdes_wrap_cbc());                 \
 169 }                                                                              \
 170 static OSSL_OP_cipher_get_params_fn tdes_wrap_get_params;                      \
 171 static int tdes_wrap_get_params(OSSL_PARAM params[])                           \
 172 {                                                                              \
 173     return cipher_generic_get_params(params, EVP_CIPH_WRAP_MODE, flags,        \
 174                                      kbits, blkbits, ivbits);                  \
 175 }                                                                              \
 176 const OSSL_DISPATCH tdes_wrap_cbc_functions[] =                                \
 177 {                                                                              \
 178     { OSSL_FUNC_CIPHER_ENCRYPT_INIT, (void (*)(void)) tdes_einit },            \
 179     { OSSL_FUNC_CIPHER_DECRYPT_INIT, (void (*)(void)) tdes_dinit },            \
 180     { OSSL_FUNC_CIPHER_CIPHER, (void (*)(void))tdes_wrap_cipher },             \
 181     { OSSL_FUNC_CIPHER_NEWCTX, (void (*)(void))tdes_wrap_newctx },             \
 182     { OSSL_FUNC_CIPHER_FREECTX, (void (*)(void))tdes_freectx },                \
 183     { OSSL_FUNC_CIPHER_UPDATE, (void (*)(void))tdes_wrap_update },             \
 184     { OSSL_FUNC_CIPHER_FINAL, (void (*)(void))cipher_generic_stream_final },   \
 185     { OSSL_FUNC_CIPHER_GET_PARAMS, (void (*)(void))tdes_wrap_get_params },     \
 186     { OSSL_FUNC_CIPHER_GETTABLE_PARAMS,                                        \
 187       (void (*)(void))cipher_generic_gettable_params },                        \
 188     { OSSL_FUNC_CIPHER_GET_CTX_PARAMS, (void (*)(void))tdes_get_ctx_params },  \
 189     { OSSL_FUNC_CIPHER_GETTABLE_CTX_PARAMS,                                    \
 190       (void (*)(void))tdes_gettable_ctx_params },                              \
 191     { OSSL_FUNC_CIPHER_SET_CTX_PARAMS,                                         \
 192       (void (*)(void))cipher_generic_set_ctx_params },                         \
 193     { OSSL_FUNC_CIPHER_SETTABLE_CTX_PARAMS,                                    \
 194       (void (*)(void))cipher_generic_settable_ctx_params },                    \
 195     { 0, NULL }                                                                \
 196 }
 197
 198 /* tdes_wrap_cbc_functions */
 199 IMPLEMENT_WRAP_CIPHER(TDES_WRAP_FLAGS, 64*3, 64, 0);