providers/implementations/ciphers/cipher_tdes_wrap.c

   1 /*
   2  * Copyright 1995-2020 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 /*
  11  * DES and SHA-1 low level APIs are deprecated for public use, but still ok for
  12  * internal use.
  13  */
  14 #include "internal/deprecated.h"
  15
  16 #include <openssl/sha.h>
  17 #include <openssl/rand.h>
  18 #include "cipher_tdes_default.h"
  19 #include "crypto/evp.h"
  20 #include "prov/implementations.h"
  21 #include "prov/providercommon.h"
  22 #include "prov/providercommonerr.h"
  23
  24 /* TODO (3.0) Figure out what flags are required */
  25 #define TDES_WRAP_FLAGS (EVP_CIPH_WRAP_MODE | EVP_CIPH_CUSTOM_IV)
  26
  27
  28 static OSSL_FUNC_cipher_update_fn tdes_wrap_update;
  29 static OSSL_FUNC_cipher_cipher_fn tdes_wrap_cipher;
  30
  31 static const unsigned char wrap_iv[8] =
  32 {
  33     0x4a, 0xdd, 0xa2, 0x2c, 0x79, 0xe8, 0x21, 0x05
  34 };
  35
  36 static int des_ede3_unwrap(PROV_CIPHER_CTX *ctx, unsigned char *out,
  37                            const unsigned char *in, size_t inl)
  38 {
  39     unsigned char icv[8], iv[TDES_IVLEN], sha1tmp[SHA_DIGEST_LENGTH];
  40     int rv = -1;
  41
  42     if (inl < 24)
  43         return -1;
  44     if (out == NULL)
  45         return inl - 16;
  46
  47     memcpy(ctx->iv, wrap_iv, 8);
  48     /* Decrypt first block which will end up as icv */
  49     ctx->hw->cipher(ctx, icv, in, 8);
  50     /* Decrypt central blocks */
  51     /*
  52      * If decrypting in place move whole output along a block so the next
  53      * des_ede_cbc_cipher is in place.
  54      */
  55     if (out == in) {
  56         memmove(out, out + 8, inl - 8);
  57         in -= 8;
  58     }
  59     ctx->hw->cipher(ctx, out, in + 8, inl - 16);
  60     /* Decrypt final block which will be IV */
  61     ctx->hw->cipher(ctx, iv, in + inl - 8, 8);
  62     /* Reverse order of everything */
  63     BUF_reverse(icv, NULL, 8);
  64     BUF_reverse(out, NULL, inl - 16);
  65     BUF_reverse(ctx->iv, iv, 8);
  66     /* Decrypt again using new IV */
  67     ctx->hw->cipher(ctx, out, out, inl - 16);
  68     ctx->hw->cipher(ctx, icv, icv, 8);
  69     /* Work out SHA1 hash of first portion */
  70     SHA1(out, inl - 16, sha1tmp);
  71
  72     if (!CRYPTO_memcmp(sha1tmp, icv, 8))
  73         rv = inl - 16;
  74     OPENSSL_cleanse(icv, 8);
  75     OPENSSL_cleanse(sha1tmp, SHA_DIGEST_LENGTH);
  76     OPENSSL_cleanse(iv, 8);
  77     OPENSSL_cleanse(ctx->iv, sizeof(ctx->iv));
  78     if (rv == -1)
  79         OPENSSL_cleanse(out, inl - 16);
  80
  81     return rv;
  82 }
  83
  84 static int des_ede3_wrap(PROV_CIPHER_CTX *ctx, unsigned char *out,
  85                          const unsigned char *in, size_t inl)
  86 {
  87     unsigned char sha1tmp[SHA_DIGEST_LENGTH];
  88     size_t ivlen = TDES_IVLEN;
  89     size_t icvlen = TDES_IVLEN;
  90     size_t len = inl + ivlen + icvlen;
  91
  92     if (out == NULL)
  93         return len;
  94
  95     /* Copy input to output buffer + 8 so we have space for IV */
  96     memmove(out + ivlen, in, inl);
  97     /* Work out ICV */
  98     SHA1(in, inl, sha1tmp);
  99     memcpy(out + inl + ivlen, sha1tmp, icvlen);
 100     OPENSSL_cleanse(sha1tmp, SHA_DIGEST_LENGTH);
 101     /* Generate random IV */
 102     if (RAND_bytes_ex(ctx->libctx, ctx->iv, ivlen) <= 0)
 103         return 0;
 104     memcpy(out, ctx->iv, ivlen);
 105     /* Encrypt everything after IV in place */
 106     ctx->hw->cipher(ctx, out + ivlen, out + ivlen, inl + ivlen);
 107     BUF_reverse(out, NULL, len);
 108     memcpy(ctx->iv, wrap_iv, ivlen);
 109     ctx->hw->cipher(ctx, out, out, len);
 110     return len;
 111 }
 112
 113 static int tdes_wrap_cipher_internal(PROV_CIPHER_CTX *ctx, unsigned char *out,
 114                                      const unsigned char *in, size_t inl)
 115 {
 116     /*
 117      * Sanity check input length: we typically only wrap keys so EVP_MAXCHUNK
 118      * is more than will ever be needed. Also input length must be a multiple
 119      * of 8 bits.
 120      */
 121     if (inl >= EVP_MAXCHUNK || inl % 8)
 122         return -1;
 123     if (ctx->enc)
 124         return des_ede3_wrap(ctx, out, in, inl);
 125     else
 126         return des_ede3_unwrap(ctx, out, in, inl);
 127 }
 128
 129 static int tdes_wrap_cipher(void *vctx,
 130                             unsigned char *out, size_t *outl, size_t outsize,
 131                             const unsigned char *in, size_t inl)
 132 {
 133     PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
 134     int ret;
 135
 136     *outl = 0;
 137     if (!ossl_prov_is_running())
 138         return 0;
 139
 140     if (outsize < inl) {
 141         PROVerr(0, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
 142         return 0;
 143     }
 144
 145     ret = tdes_wrap_cipher_internal(ctx, out, in, inl);
 146     if (ret <= 0)
 147         return 0;
 148
 149     *outl = ret;
 150     return 1;
 151 }
 152
 153 static int tdes_wrap_update(void *vctx, unsigned char *out, size_t *outl,
 154                             size_t outsize, const unsigned char *in,
 155                             size_t inl)
 156 {
 157     *outl = 0;
 158     if (inl == 0)
 159         return 1;
 160     if (outsize < inl) {
 161         PROVerr(0, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
 162         return 0;
 163     }
 164
 165     if (!tdes_wrap_cipher(vctx, out, outl, outsize, in, inl)) {
 166         PROVerr(0, PROV_R_CIPHER_OPERATION_FAILED);
 167         return 0;
 168     }
 169     return 1;
 170 }
 171
 172
 173 # define IMPLEMENT_WRAP_CIPHER(flags, kbits, blkbits, ivbits)                  \
 174 static OSSL_FUNC_cipher_newctx_fn tdes_wrap_newctx;                            \
 175 static void *tdes_wrap_newctx(void *provctx)                                   \
 176 {                                                                              \
 177     return tdes_newctx(provctx, EVP_CIPH_WRAP_MODE, kbits, blkbits, ivbits,    \
 178                        flags, ossl_prov_cipher_hw_tdes_wrap_cbc());            \
 179 }                                                                              \
 180 static OSSL_FUNC_cipher_get_params_fn tdes_wrap_get_params;                    \
 181 static int tdes_wrap_get_params(OSSL_PARAM params[])                           \
 182 {                                                                              \
 183     return ossl_cipher_generic_get_params(params, EVP_CIPH_WRAP_MODE, flags,   \
 184                                           kbits, blkbits, ivbits);             \
 185 }                                                                              \
 186 const OSSL_DISPATCH ossl_tdes_wrap_cbc_functions[] =                           \
 187 {                                                                              \
 188     { OSSL_FUNC_CIPHER_ENCRYPT_INIT, (void (*)(void)) tdes_einit },            \
 189     { OSSL_FUNC_CIPHER_DECRYPT_INIT, (void (*)(void)) tdes_dinit },            \
 190     { OSSL_FUNC_CIPHER_CIPHER, (void (*)(void))tdes_wrap_cipher },             \
 191     { OSSL_FUNC_CIPHER_NEWCTX, (void (*)(void))tdes_wrap_newctx },             \
 192     { OSSL_FUNC_CIPHER_FREECTX, (void (*)(void))tdes_freectx },                \
 193     { OSSL_FUNC_CIPHER_UPDATE, (void (*)(void))tdes_wrap_update },             \
 194     { OSSL_FUNC_CIPHER_FINAL, (void (*)(void))ossl_cipher_generic_stream_final },\
 195     { OSSL_FUNC_CIPHER_GET_PARAMS, (void (*)(void))tdes_wrap_get_params },     \
 196     { OSSL_FUNC_CIPHER_GETTABLE_PARAMS,                                        \
 197       (void (*)(void))ossl_cipher_generic_gettable_params },                   \
 198     { OSSL_FUNC_CIPHER_GET_CTX_PARAMS, (void (*)(void))tdes_get_ctx_params },  \
 199     { OSSL_FUNC_CIPHER_GETTABLE_CTX_PARAMS,                                    \
 200       (void (*)(void))tdes_gettable_ctx_params },                              \
 201     { OSSL_FUNC_CIPHER_SET_CTX_PARAMS,                                         \
 202       (void (*)(void))ossl_cipher_generic_set_ctx_params },                    \
 203     { OSSL_FUNC_CIPHER_SETTABLE_CTX_PARAMS,                                    \
 204       (void (*)(void))ossl_cipher_generic_settable_ctx_params },               \
 205     { 0, NULL }                                                                \
 206 }
 207
 208 /* ossl_tdes_wrap_cbc_functions */
 209 IMPLEMENT_WRAP_CIPHER(TDES_WRAP_FLAGS, 64*3, 64, 0);