/*

 * Copyright 1995-2024 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 <openssl/proverr.h>

#include "cipher_tdes_default.h"

#include "crypto/evp.h"

#include "crypto/sha.h"

#include "prov/implementations.h"

#include "prov/providercommon.h"

#define TDES_WRAP_FLAGS PROV_CIPHER_FLAG_CUSTOM_IV | PROV_CIPHER_FLAG_RAND_KEY

static OSSL_FUNC_cipher_update_fn tdes_wrap_update;

static OSSL_FUNC_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);

    if (ossl_sha1(out, inl - 16, sha1tmp) /* Work out hash of first portion */

            && CRYPTO_memcmp(sha1tmp, icv, 8) == 0)

        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 */

    if (!ossl_sha1(in, inl, sha1tmp))

        return 0;

    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) <= 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 (!ossl_prov_is_running())

        return 0;

    if (outsize < inl) {

        ERR_raise(ERR_LIB_PROV, 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) {

        ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL);

        return 0;

    }

    if (!tdes_wrap_cipher(vctx, out, outl, outsize, in, inl)) {

        ERR_raise(ERR_LIB_PROV, PROV_R_CIPHER_OPERATION_FAILED);

        return 0;

    }

    return 1;

}

# define IMPLEMENT_WRAP_CIPHER(flags, kbits, blkbits, ivbits)                  \

static OSSL_FUNC_cipher_newctx_fn tdes_wrap_newctx;                            \

static void *tdes_wrap_newctx(void *provctx)                                   \

{                                                                              \

    return ossl_tdes_newctx(provctx, EVP_CIPH_WRAP_MODE, kbits, blkbits,       \

                            ivbits, flags,                                     \

                            ossl_prov_cipher_hw_tdes_wrap_cbc());              \

}                                                                              \

static OSSL_FUNC_cipher_get_params_fn tdes_wrap_get_params;                    \

static int tdes_wrap_get_params(OSSL_PARAM params[])                           \

{                                                                              \

    return ossl_cipher_generic_get_params(params, EVP_CIPH_WRAP_MODE, flags,   \

                                          kbits, blkbits, ivbits);             \

}                                                                              \

const OSSL_DISPATCH ossl_tdes_wrap_cbc_functions[] =                           \

{                                                                              \

    { OSSL_FUNC_CIPHER_ENCRYPT_INIT, (void (*)(void)) ossl_tdes_einit },       \

    { OSSL_FUNC_CIPHER_DECRYPT_INIT, (void (*)(void)) ossl_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))ossl_tdes_freectx },           \

    { OSSL_FUNC_CIPHER_UPDATE, (void (*)(void))tdes_wrap_update },             \

    { OSSL_FUNC_CIPHER_FINAL,                                                  \

      (void (*)(void))ossl_cipher_generic_stream_final },                      \

    { OSSL_FUNC_CIPHER_GET_PARAMS, (void (*)(void))tdes_wrap_get_params },     \

    { OSSL_FUNC_CIPHER_GETTABLE_PARAMS,                                        \

      (void (*)(void))ossl_cipher_generic_gettable_params },                   \

    { OSSL_FUNC_CIPHER_GET_CTX_PARAMS,                                         \

      (void (*)(void))ossl_tdes_get_ctx_params },                              \

    { OSSL_FUNC_CIPHER_GETTABLE_CTX_PARAMS,                                    \

      (void (*)(void))ossl_tdes_gettable_ctx_params },                         \

    { OSSL_FUNC_CIPHER_SET_CTX_PARAMS,                                         \

      (void (*)(void))ossl_cipher_generic_set_ctx_params },                    \

    { OSSL_FUNC_CIPHER_SETTABLE_CTX_PARAMS,                                    \

      (void (*)(void))ossl_cipher_generic_settable_ctx_params },               \

    OSSL_DISPATCH_END                                                          \

}

/* ossl_tdes_wrap_cbc_functions */

IMPLEMENT_WRAP_CIPHER(TDES_WRAP_FLAGS, 64*3, 64, 0);