godot/thirdparty/mbedtls/library/nist_kw.c

/*
 *  Implementation of NIST SP 800-38F key wrapping, supporting KW and KWP modes
 *  only
 *
 *  Copyright The Mbed TLS Contributors
 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
 */
/*
 * Definition of Key Wrapping:
 * https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-38F.pdf
 * RFC 3394 "Advanced Encryption Standard (AES) Key Wrap Algorithm"
 * RFC 5649 "Advanced Encryption Standard (AES) Key Wrap with Padding Algorithm"
 *
 * Note: RFC 3394 defines different methodology for intermediate operations for
 * the wrapping and unwrapping operation than the definition in NIST SP 800-38F.
 */

#include "common.h"

#if defined(MBEDTLS_NIST_KW_C)

#include "mbedtls/nist_kw.h"
#include "mbedtls/platform_util.h"
#include "mbedtls/error.h"
#include "mbedtls/constant_time.h"
#include "constant_time_internal.h"

#include <stdint.h>
#include <string.h>

#include "mbedtls/platform.h"

#if !defined(MBEDTLS_NIST_KW_ALT)

#define KW_SEMIBLOCK_LENGTH …
#define MIN_SEMIBLOCKS_COUNT …

/*! The 64-bit default integrity check value (ICV) for KW mode. */
static const unsigned char NIST_KW_ICV1[] = …;
/*! The 32-bit default integrity check value (ICV) for KWP mode. */
static const  unsigned char NIST_KW_ICV2[] = …;

/*
 * Initialize context
 */
void mbedtls_nist_kw_init(mbedtls_nist_kw_context *ctx)
{ … }

int mbedtls_nist_kw_setkey(mbedtls_nist_kw_context *ctx,
                           mbedtls_cipher_id_t cipher,
                           const unsigned char *key,
                           unsigned int keybits,
                           const int is_wrap)
{ … }

/*
 * Free context
 */
void mbedtls_nist_kw_free(mbedtls_nist_kw_context *ctx)
{ … }

/*
 * Helper function for Xoring the uint64_t "t" with the encrypted A.
 * Defined in NIST SP 800-38F section 6.1
 */
static void calc_a_xor_t(unsigned char A[KW_SEMIBLOCK_LENGTH], uint64_t t)
{ … }

/*
 * KW-AE as defined in SP 800-38F section 6.2
 * KWP-AE as defined in SP 800-38F section 6.3
 */
int mbedtls_nist_kw_wrap(mbedtls_nist_kw_context *ctx,
                         mbedtls_nist_kw_mode_t mode,
                         const unsigned char *input, size_t in_len,
                         unsigned char *output, size_t *out_len, size_t out_size)
{ … }

/*
 * W-1 function as defined in RFC 3394 section 2.2.2
 * This function assumes the following:
 * 1. Output buffer is at least of size ( semiblocks - 1 ) * KW_SEMIBLOCK_LENGTH.
 * 2. The input buffer is of size semiblocks * KW_SEMIBLOCK_LENGTH.
 * 3. Minimal number of semiblocks is 3.
 * 4. A is a buffer to hold the first semiblock of the input buffer.
 */
static int unwrap(mbedtls_nist_kw_context *ctx,
                  const unsigned char *input, size_t semiblocks,
                  unsigned char A[KW_SEMIBLOCK_LENGTH],
                  unsigned char *output, size_t *out_len)
{ … }

/*
 * KW-AD as defined in SP 800-38F section 6.2
 * KWP-AD as defined in SP 800-38F section 6.3
 */
int mbedtls_nist_kw_unwrap(mbedtls_nist_kw_context *ctx,
                           mbedtls_nist_kw_mode_t mode,
                           const unsigned char *input, size_t in_len,
                           unsigned char *output, size_t *out_len, size_t out_size)
{ … }

#endif /* !MBEDTLS_NIST_KW_ALT */

#if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)

/*
 * Test vectors taken from NIST
 * https://csrc.nist.gov/Projects/Cryptographic-Algorithm-Validation-Program/CAVP-TESTING-BLOCK-CIPHER-MODES#KW
 */
static const unsigned int key_len[] = …;

static const unsigned char kw_key[][32] = …;

static const unsigned char kw_msg[][40] = …;

static const size_t kw_msg_len[] = …;
static const size_t kw_out_len[] = …;
static const unsigned char kw_res[][48] = …;

static const unsigned char kwp_key[][32] = …;

static const unsigned char kwp_msg[][31] = …;
static const size_t kwp_msg_len[] = …;

static const unsigned char kwp_res[][48] = …;
static const size_t kwp_out_len[] = …;

int mbedtls_nist_kw_self_test(int verbose)
{ … }

#endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */

#endif /* MBEDTLS_NIST_KW_C */