poly1305.c | Explore in Territory

/**
 * \file poly1305.c
 *
 * \brief Poly1305 authentication algorithm.
 *
 *  Copyright The Mbed TLS Contributors
 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
 */
#include "common.h"

#if defined(MBEDTLS_POLY1305_C)

#include "mbedtls/poly1305.h"
#include "mbedtls/platform_util.h"
#include "mbedtls/error.h"

#include <string.h>

#include "mbedtls/platform.h"

#if !defined(MBEDTLS_POLY1305_ALT)

#define POLY1305_BLOCK_SIZE_BYTES …

/*
 * Our implementation is tuned for 32-bit platforms with a 64-bit multiplier.
 * However we provided an alternative for platforms without such a multiplier.
 */
#if defined(MBEDTLS_NO_64BIT_MULTIPLICATION)
static uint64_t mul64(uint32_t a, uint32_t b)
{
    /* a = al + 2**16 ah, b = bl + 2**16 bh */
    const uint16_t al = (uint16_t) a;
    const uint16_t bl = (uint16_t) b;
    const uint16_t ah = a >> 16;
    const uint16_t bh = b >> 16;

    /* ab = al*bl + 2**16 (ah*bl + bl*bh) + 2**32 ah*bh */
    const uint32_t lo = (uint32_t) al * bl;
    const uint64_t me = (uint64_t) ((uint32_t) ah * bl) + (uint32_t) al * bh;
    const uint32_t hi = (uint32_t) ah * bh;

    return lo + (me << 16) + ((uint64_t) hi << 32);
}
#else
static inline uint64_t mul64(uint32_t a, uint32_t b)
{ … }
#endif


/**
 * \brief                   Process blocks with Poly1305.
 *
 * \param ctx               The Poly1305 context.
 * \param nblocks           Number of blocks to process. Note that this
 *                          function only processes full blocks.
 * \param input             Buffer containing the input block(s).
 * \param needs_padding     Set to 0 if the padding bit has already been
 *                          applied to the input data before calling this
 *                          function.  Otherwise, set this parameter to 1.
 */
static void poly1305_process(mbedtls_poly1305_context *ctx,
                             size_t nblocks,
                             const unsigned char *input,
                             uint32_t needs_padding)
{ … }

/**
 * \brief                   Compute the Poly1305 MAC
 *
 * \param ctx               The Poly1305 context.
 * \param mac               The buffer to where the MAC is written. Must be
 *                          big enough to contain the 16-byte MAC.
 */
static void poly1305_compute_mac(const mbedtls_poly1305_context *ctx,
                                 unsigned char mac[16])
{ … }

void mbedtls_poly1305_init(mbedtls_poly1305_context *ctx)
{ … }

void mbedtls_poly1305_free(mbedtls_poly1305_context *ctx)
{ … }

int mbedtls_poly1305_starts(mbedtls_poly1305_context *ctx,
                            const unsigned char key[32])
{ … }

int mbedtls_poly1305_update(mbedtls_poly1305_context *ctx,
                            const unsigned char *input,
                            size_t ilen)
{ … }

int mbedtls_poly1305_finish(mbedtls_poly1305_context *ctx,
                            unsigned char mac[16])
{ … }

int mbedtls_poly1305_mac(const unsigned char key[32],
                         const unsigned char *input,
                         size_t ilen,
                         unsigned char mac[16])
{ … }

#endif /* MBEDTLS_POLY1305_ALT */

#if defined(MBEDTLS_SELF_TEST)

static const unsigned char test_keys[2][32] = …;

static const unsigned char test_data[2][127] = …;

static const size_t test_data_len[2] = …;

static const unsigned char test_mac[2][16] = …;

/* Make sure no other definition is already present. */
#undef ASSERT

#define ASSERT(cond, args) …

int mbedtls_poly1305_self_test(int verbose)
{ … }

#endif /* MBEDTLS_SELF_TEST */

#endif /* MBEDTLS_POLY1305_C */
godot/thirdparty/mbedtls/library/poly1305.c
