cipher_tdes_wrap.c
/*
* Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
/*
* DES and SHA-1 low level APIs are deprecated for public use, but still ok for
* internal use.
*/
#include "internal/deprecated.h"
#include <openssl/sha.h>
#include <openssl/rand.h>
#include "cipher_tdes_default.h"
#include "crypto/evp.h"
#include "prov/implementations.h"
#include "prov/providercommonerr.h"
/* TODO (3.0) Figure out what flags are required */
#define TDES_WRAP_FLAGS (EVP_CIPH_WRAP_MODE | EVP_CIPH_CUSTOM_IV)
static OSSL_OP_cipher_update_fn tdes_wrap_update;
static OSSL_OP_cipher_cipher_fn tdes_wrap_cipher;
static const unsigned char wrap_iv[8] =
{
0x4a, 0xdd, 0xa2, 0x2c, 0x79, 0xe8, 0x21, 0x05
};
static int des_ede3_unwrap(PROV_CIPHER_CTX *ctx, unsigned char *out,
const unsigned char *in, size_t inl)
{
unsigned char icv[8], iv[TDES_IVLEN], sha1tmp[SHA_DIGEST_LENGTH];
int rv = -1;
if (inl < 24)
return -1;
if (out == NULL)
return inl - 16;
memcpy(ctx->iv, wrap_iv, 8);
/* Decrypt first block which will end up as icv */
ctx->hw->cipher(ctx, icv, in, 8);
/* Decrypt central blocks */
/*
* If decrypting in place move whole output along a block so the next
* des_ede_cbc_cipher is in place.
*/
if (out == in) {
memmove(out, out + 8, inl - 8);
in -= 8;
}
ctx->hw->cipher(ctx, out, in + 8, inl - 16);
/* Decrypt final block which will be IV */
ctx->hw->cipher(ctx, iv, in + inl - 8, 8);
/* Reverse order of everything */
BUF_reverse(icv, NULL, 8);
BUF_reverse(out, NULL, inl - 16);
BUF_reverse(ctx->iv, iv, 8);
/* Decrypt again using new IV */
ctx->hw->cipher(ctx, out, out, inl - 16);
ctx->hw->cipher(ctx, icv, icv, 8);
/* Work out SHA1 hash of first portion */
SHA1(out, inl - 16, sha1tmp);
if (!CRYPTO_memcmp(sha1tmp, icv, 8))
rv = inl - 16;
OPENSSL_cleanse(icv, 8);
OPENSSL_cleanse(sha1tmp, SHA_DIGEST_LENGTH);
OPENSSL_cleanse(iv, 8);
OPENSSL_cleanse(ctx->iv, sizeof(ctx->iv));
if (rv == -1)
OPENSSL_cleanse(out, inl - 16);
return rv;
}
static int des_ede3_wrap(PROV_CIPHER_CTX *ctx, unsigned char *out,
const unsigned char *in, size_t inl)
{
unsigned char sha1tmp[SHA_DIGEST_LENGTH];
size_t ivlen = TDES_IVLEN;
size_t icvlen = TDES_IVLEN;
size_t len = inl + ivlen + icvlen;
if (out == NULL)
return len;
/* Copy input to output buffer + 8 so we have space for IV */
memmove(out + ivlen, in, inl);
/* Work out ICV */
SHA1(in, inl, sha1tmp);
memcpy(out + inl + ivlen, sha1tmp, icvlen);
OPENSSL_cleanse(sha1tmp, SHA_DIGEST_LENGTH);
/* Generate random IV */
if (RAND_bytes_ex(ctx->libctx, ctx->iv, ivlen) <= 0)
return 0;
memcpy(out, ctx->iv, ivlen);
/* Encrypt everything after IV in place */
ctx->hw->cipher(ctx, out + ivlen, out + ivlen, inl + ivlen);
BUF_reverse(out, NULL, len);
memcpy(ctx->iv, wrap_iv, ivlen);
ctx->hw->cipher(ctx, out, out, len);
return len;
}
static int tdes_wrap_cipher_internal(PROV_CIPHER_CTX *ctx, unsigned char *out,
const unsigned char *in, size_t inl)
{
/*
* Sanity check input length: we typically only wrap keys so EVP_MAXCHUNK
* is more than will ever be needed. Also input length must be a multiple
* of 8 bits.
*/
if (inl >= EVP_MAXCHUNK || inl % 8)
return -1;
if (ctx->enc)
return des_ede3_wrap(ctx, out, in, inl);
else
return des_ede3_unwrap(ctx, out, in, inl);
}
static int tdes_wrap_cipher(void *vctx,
unsigned char *out, size_t *outl, size_t outsize,
const unsigned char *in, size_t inl)
{
PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
int ret;
*outl = 0;
if (outsize < inl) {
PROVerr(0, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
return 0;
}
ret = tdes_wrap_cipher_internal(ctx, out, in, inl);
if (ret <= 0)
return 0;
*outl = ret;
return 1;
}
static int tdes_wrap_update(void *vctx, unsigned char *out, size_t *outl,
size_t outsize, const unsigned char *in,
size_t inl)
{
*outl = 0;
if (inl == 0)
return 1;
if (outsize < inl) {
PROVerr(0, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
return 0;
}
if (!tdes_wrap_cipher(vctx, out, outl, outsize, in, inl)) {
PROVerr(0, PROV_R_CIPHER_OPERATION_FAILED);
return 0;
}
return 1;
}
# define IMPLEMENT_WRAP_CIPHER(flags, kbits, blkbits, ivbits) \
static OSSL_OP_cipher_newctx_fn tdes_wrap_newctx; \
static void *tdes_wrap_newctx(void *provctx) \
{ \
return tdes_newctx(provctx, EVP_CIPH_WRAP_MODE, kbits, blkbits, ivbits, \
flags, PROV_CIPHER_HW_tdes_wrap_cbc()); \
} \
static OSSL_OP_cipher_get_params_fn tdes_wrap_get_params; \
static int tdes_wrap_get_params(OSSL_PARAM params[]) \
{ \
return cipher_generic_get_params(params, EVP_CIPH_WRAP_MODE, flags, \
kbits, blkbits, ivbits); \
} \
const OSSL_DISPATCH tdes_wrap_cbc_functions[] = \
{ \
{ OSSL_FUNC_CIPHER_ENCRYPT_INIT, (void (*)(void)) tdes_einit }, \
{ OSSL_FUNC_CIPHER_DECRYPT_INIT, (void (*)(void)) tdes_dinit }, \
{ OSSL_FUNC_CIPHER_CIPHER, (void (*)(void))tdes_wrap_cipher }, \
{ OSSL_FUNC_CIPHER_NEWCTX, (void (*)(void))tdes_wrap_newctx }, \
{ OSSL_FUNC_CIPHER_FREECTX, (void (*)(void))tdes_freectx }, \
{ OSSL_FUNC_CIPHER_UPDATE, (void (*)(void))tdes_wrap_update }, \
{ OSSL_FUNC_CIPHER_FINAL, (void (*)(void))cipher_generic_stream_final }, \
{ OSSL_FUNC_CIPHER_GET_PARAMS, (void (*)(void))tdes_wrap_get_params }, \
{ OSSL_FUNC_CIPHER_GETTABLE_PARAMS, \
(void (*)(void))cipher_generic_gettable_params }, \
{ OSSL_FUNC_CIPHER_GET_CTX_PARAMS, (void (*)(void))tdes_get_ctx_params }, \
{ OSSL_FUNC_CIPHER_GETTABLE_CTX_PARAMS, \
(void (*)(void))tdes_gettable_ctx_params }, \
{ OSSL_FUNC_CIPHER_SET_CTX_PARAMS, \
(void (*)(void))cipher_generic_set_ctx_params }, \
{ OSSL_FUNC_CIPHER_SETTABLE_CTX_PARAMS, \
(void (*)(void))cipher_generic_settable_ctx_params }, \
{ 0, NULL } \
}
/* tdes_wrap_cbc_functions */
IMPLEMENT_WRAP_CIPHER(TDES_WRAP_FLAGS, 64*3, 64, 0);
