lib/mbedtls
1
0
Fork 0
mirror of https://github.com/Mbed-TLS/mbedtls.git synced 2025-10-26 00:37:41 +03:00
Code Activity
Files
d0ac48087bbbcabf13c08861c55fd2e4add979fd
mbedtls/library/poly1305.c
Dave Rodgman 0f2971a968 Update headers 
Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
2023-11-03 12:54:54 +00:00

512 lines
15 KiB
C
Raw Blame History

/**
* \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)
/* Parameter validation macros */
#define POLY1305_VALIDATE_RET(cond) \
MBEDTLS_INTERNAL_VALIDATE_RET(cond, MBEDTLS_ERR_POLY1305_BAD_INPUT_DATA)
#define POLY1305_VALIDATE(cond) \
MBEDTLS_INTERNAL_VALIDATE(cond)
#define POLY1305_BLOCK_SIZE_BYTES (16U)
/*
* 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)
{
return (uint64_t) a * 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)
{
uint64_t d0, d1, d2, d3;
uint32_t acc0, acc1, acc2, acc3, acc4;
uint32_t r0, r1, r2, r3;
uint32_t rs1, rs2, rs3;
size_t offset = 0U;
size_t i;
r0 = ctx->r[0];
r1 = ctx->r[1];
r2 = ctx->r[2];
r3 = ctx->r[3];
rs1 = r1 + (r1 >> 2U);
rs2 = r2 + (r2 >> 2U);
rs3 = r3 + (r3 >> 2U);
acc0 = ctx->acc[0];
acc1 = ctx->acc[1];
acc2 = ctx->acc[2];
acc3 = ctx->acc[3];
acc4 = ctx->acc[4];
/* Process full blocks */
for (i = 0U; i < nblocks; i++) {
/* The input block is treated as a 128-bit little-endian integer */
d0 = MBEDTLS_GET_UINT32_LE(input, offset + 0);
d1 = MBEDTLS_GET_UINT32_LE(input, offset + 4);
d2 = MBEDTLS_GET_UINT32_LE(input, offset + 8);
d3 = MBEDTLS_GET_UINT32_LE(input, offset + 12);
/* Compute: acc += (padded) block as a 130-bit integer */
d0 += (uint64_t) acc0;
d1 += (uint64_t) acc1 + (d0 >> 32U);
d2 += (uint64_t) acc2 + (d1 >> 32U);
d3 += (uint64_t) acc3 + (d2 >> 32U);
acc0 = (uint32_t) d0;
acc1 = (uint32_t) d1;
acc2 = (uint32_t) d2;
acc3 = (uint32_t) d3;
acc4 += (uint32_t) (d3 >> 32U) + needs_padding;
/* Compute: acc *= r */
d0 = mul64(acc0, r0) +
mul64(acc1, rs3) +
mul64(acc2, rs2) +
mul64(acc3, rs1);
d1 = mul64(acc0, r1) +
mul64(acc1, r0) +
mul64(acc2, rs3) +
mul64(acc3, rs2) +
mul64(acc4, rs1);
d2 = mul64(acc0, r2) +
mul64(acc1, r1) +
mul64(acc2, r0) +
mul64(acc3, rs3) +
mul64(acc4, rs2);
d3 = mul64(acc0, r3) +
mul64(acc1, r2) +
mul64(acc2, r1) +
mul64(acc3, r0) +
mul64(acc4, rs3);
acc4 *= r0;
/* Compute: acc %= (2^130 - 5) (partial remainder) */
d1 += (d0 >> 32);
d2 += (d1 >> 32);
d3 += (d2 >> 32);
acc0 = (uint32_t) d0;
acc1 = (uint32_t) d1;
acc2 = (uint32_t) d2;
acc3 = (uint32_t) d3;
acc4 = (uint32_t) (d3 >> 32) + acc4;
d0 = (uint64_t) acc0 + (acc4 >> 2) + (acc4 & 0xFFFFFFFCU);
acc4 &= 3U;
acc0 = (uint32_t) d0;
d0 = (uint64_t) acc1 + (d0 >> 32U);
acc1 = (uint32_t) d0;
d0 = (uint64_t) acc2 + (d0 >> 32U);
acc2 = (uint32_t) d0;
d0 = (uint64_t) acc3 + (d0 >> 32U);
acc3 = (uint32_t) d0;
d0 = (uint64_t) acc4 + (d0 >> 32U);
acc4 = (uint32_t) d0;
offset += POLY1305_BLOCK_SIZE_BYTES;
}
ctx->acc[0] = acc0;
ctx->acc[1] = acc1;
ctx->acc[2] = acc2;
ctx->acc[3] = acc3;
ctx->acc[4] = acc4;
}
/**
* \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])
{
uint64_t d;
uint32_t g0, g1, g2, g3, g4;
uint32_t acc0, acc1, acc2, acc3, acc4;
uint32_t mask;
uint32_t mask_inv;
acc0 = ctx->acc[0];
acc1 = ctx->acc[1];
acc2 = ctx->acc[2];
acc3 = ctx->acc[3];
acc4 = ctx->acc[4];
/* Before adding 's' we ensure that the accumulator is mod 2^130 - 5.
* We do this by calculating acc - (2^130 - 5), then checking if
* the 131st bit is set. If it is, then reduce: acc -= (2^130 - 5)
*/
/* Calculate acc + -(2^130 - 5) */
d = ((uint64_t) acc0 + 5U);
g0 = (uint32_t) d;
d = ((uint64_t) acc1 + (d >> 32));
g1 = (uint32_t) d;
d = ((uint64_t) acc2 + (d >> 32));
g2 = (uint32_t) d;
d = ((uint64_t) acc3 + (d >> 32));
g3 = (uint32_t) d;
g4 = acc4 + (uint32_t) (d >> 32U);
/* mask == 0xFFFFFFFF if 131st bit is set, otherwise mask == 0 */
mask = (uint32_t) 0U - (g4 >> 2U);
mask_inv = ~mask;
/* If 131st bit is set then acc=g, otherwise, acc is unmodified */
acc0 = (acc0 & mask_inv) | (g0 & mask);
acc1 = (acc1 & mask_inv) | (g1 & mask);
acc2 = (acc2 & mask_inv) | (g2 & mask);
acc3 = (acc3 & mask_inv) | (g3 & mask);
/* Add 's' */
d = (uint64_t) acc0 + ctx->s[0];
acc0 = (uint32_t) d;
d = (uint64_t) acc1 + ctx->s[1] + (d >> 32U);
acc1 = (uint32_t) d;
d = (uint64_t) acc2 + ctx->s[2] + (d >> 32U);
acc2 = (uint32_t) d;
acc3 += ctx->s[3] + (uint32_t) (d >> 32U);
/* Compute MAC (128 least significant bits of the accumulator) */
MBEDTLS_PUT_UINT32_LE(acc0, mac, 0);
MBEDTLS_PUT_UINT32_LE(acc1, mac, 4);
MBEDTLS_PUT_UINT32_LE(acc2, mac, 8);
MBEDTLS_PUT_UINT32_LE(acc3, mac, 12);
}
void mbedtls_poly1305_init(mbedtls_poly1305_context *ctx)
{
POLY1305_VALIDATE(ctx != NULL);
mbedtls_platform_zeroize(ctx, sizeof(mbedtls_poly1305_context));
}
void mbedtls_poly1305_free(mbedtls_poly1305_context *ctx)
{
if (ctx == NULL) {
return;
}
mbedtls_platform_zeroize(ctx, sizeof(mbedtls_poly1305_context));
}
int mbedtls_poly1305_starts(mbedtls_poly1305_context *ctx,
const unsigned char key[32])
{
POLY1305_VALIDATE_RET(ctx != NULL);
POLY1305_VALIDATE_RET(key != NULL);
/* r &= 0x0ffffffc0ffffffc0ffffffc0fffffff */
ctx->r[0] = MBEDTLS_GET_UINT32_LE(key, 0) & 0x0FFFFFFFU;
ctx->r[1] = MBEDTLS_GET_UINT32_LE(key, 4) & 0x0FFFFFFCU;
ctx->r[2] = MBEDTLS_GET_UINT32_LE(key, 8) & 0x0FFFFFFCU;
ctx->r[3] = MBEDTLS_GET_UINT32_LE(key, 12) & 0x0FFFFFFCU;
ctx->s[0] = MBEDTLS_GET_UINT32_LE(key, 16);
ctx->s[1] = MBEDTLS_GET_UINT32_LE(key, 20);
ctx->s[2] = MBEDTLS_GET_UINT32_LE(key, 24);
ctx->s[3] = MBEDTLS_GET_UINT32_LE(key, 28);
/* Initial accumulator state */
ctx->acc[0] = 0U;
ctx->acc[1] = 0U;
ctx->acc[2] = 0U;
ctx->acc[3] = 0U;
ctx->acc[4] = 0U;
/* Queue initially empty */
mbedtls_platform_zeroize(ctx->queue, sizeof(ctx->queue));
ctx->queue_len = 0U;
return 0;
}
int mbedtls_poly1305_update(mbedtls_poly1305_context *ctx,
const unsigned char *input,
size_t ilen)
{
size_t offset = 0U;
size_t remaining = ilen;
size_t queue_free_len;
size_t nblocks;
POLY1305_VALIDATE_RET(ctx != NULL);
POLY1305_VALIDATE_RET(ilen == 0 || input != NULL);
if ((remaining > 0U) && (ctx->queue_len > 0U)) {
queue_free_len = (POLY1305_BLOCK_SIZE_BYTES - ctx->queue_len);
if (ilen < queue_free_len) {
/* Not enough data to complete the block.
* Store this data with the other leftovers.
*/
memcpy(&ctx->queue[ctx->queue_len],
input,
ilen);
ctx->queue_len += ilen;
remaining = 0U;
} else {
/* Enough data to produce a complete block */
memcpy(&ctx->queue[ctx->queue_len],
input,
queue_free_len);
ctx->queue_len = 0U;
poly1305_process(ctx, 1U, ctx->queue, 1U); /* add padding bit */
offset += queue_free_len;
remaining -= queue_free_len;
}
}
if (remaining >= POLY1305_BLOCK_SIZE_BYTES) {
nblocks = remaining / POLY1305_BLOCK_SIZE_BYTES;
poly1305_process(ctx, nblocks, &input[offset], 1U);
offset += nblocks * POLY1305_BLOCK_SIZE_BYTES;
remaining %= POLY1305_BLOCK_SIZE_BYTES;
}
if (remaining > 0U) {
/* Store partial block */
ctx->queue_len = remaining;
memcpy(ctx->queue, &input[offset], remaining);
}
return 0;
}
int mbedtls_poly1305_finish(mbedtls_poly1305_context *ctx,
unsigned char mac[16])
{
POLY1305_VALIDATE_RET(ctx != NULL);
POLY1305_VALIDATE_RET(mac != NULL);
/* Process any leftover data */
if (ctx->queue_len > 0U) {
/* Add padding bit */
ctx->queue[ctx->queue_len] = 1U;
ctx->queue_len++;
/* Pad with zeroes */
memset(&ctx->queue[ctx->queue_len],
0,
POLY1305_BLOCK_SIZE_BYTES - ctx->queue_len);
poly1305_process(ctx, 1U, /* Process 1 block */
ctx->queue, 0U); /* Already padded above */
}
poly1305_compute_mac(ctx, mac);
return 0;
}
int mbedtls_poly1305_mac(const unsigned char key[32],
const unsigned char *input,
size_t ilen,
unsigned char mac[16])
{
mbedtls_poly1305_context ctx;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
POLY1305_VALIDATE_RET(key != NULL);
POLY1305_VALIDATE_RET(mac != NULL);
POLY1305_VALIDATE_RET(ilen == 0 || input != NULL);
mbedtls_poly1305_init(&ctx);
ret = mbedtls_poly1305_starts(&ctx, key);
if (ret != 0) {
goto cleanup;
}
ret = mbedtls_poly1305_update(&ctx, input, ilen);
if (ret != 0) {
goto cleanup;
}
ret = mbedtls_poly1305_finish(&ctx, mac);
cleanup:
mbedtls_poly1305_free(&ctx);
return ret;
}
#endif /* MBEDTLS_POLY1305_ALT */
#if defined(MBEDTLS_SELF_TEST)
static const unsigned char test_keys[2][32] =
{
{
0x85, 0xd6, 0xbe, 0x78, 0x57, 0x55, 0x6d, 0x33,
0x7f, 0x44, 0x52, 0xfe, 0x42, 0xd5, 0x06, 0xa8,
0x01, 0x03, 0x80, 0x8a, 0xfb, 0x0d, 0xb2, 0xfd,
0x4a, 0xbf, 0xf6, 0xaf, 0x41, 0x49, 0xf5, 0x1b
},
{
0x1c, 0x92, 0x40, 0xa5, 0xeb, 0x55, 0xd3, 0x8a,
0xf3, 0x33, 0x88, 0x86, 0x04, 0xf6, 0xb5, 0xf0,
0x47, 0x39, 0x17, 0xc1, 0x40, 0x2b, 0x80, 0x09,
0x9d, 0xca, 0x5c, 0xbc, 0x20, 0x70, 0x75, 0xc0
}
};
static const unsigned char test_data[2][127] =
{
{
0x43, 0x72, 0x79, 0x70, 0x74, 0x6f, 0x67, 0x72,
0x61, 0x70, 0x68, 0x69, 0x63, 0x20, 0x46, 0x6f,
0x72, 0x75, 0x6d, 0x20, 0x52, 0x65, 0x73, 0x65,
0x61, 0x72, 0x63, 0x68, 0x20, 0x47, 0x72, 0x6f,
0x75, 0x70
},
{
0x27, 0x54, 0x77, 0x61, 0x73, 0x20, 0x62, 0x72,
0x69, 0x6c, 0x6c, 0x69, 0x67, 0x2c, 0x20, 0x61,
0x6e, 0x64, 0x20, 0x74, 0x68, 0x65, 0x20, 0x73,
0x6c, 0x69, 0x74, 0x68, 0x79, 0x20, 0x74, 0x6f,
0x76, 0x65, 0x73, 0x0a, 0x44, 0x69, 0x64, 0x20,
0x67, 0x79, 0x72, 0x65, 0x20, 0x61, 0x6e, 0x64,
0x20, 0x67, 0x69, 0x6d, 0x62, 0x6c, 0x65, 0x20,
0x69, 0x6e, 0x20, 0x74, 0x68, 0x65, 0x20, 0x77,
0x61, 0x62, 0x65, 0x3a, 0x0a, 0x41, 0x6c, 0x6c,
0x20, 0x6d, 0x69, 0x6d, 0x73, 0x79, 0x20, 0x77,
0x65, 0x72, 0x65, 0x20, 0x74, 0x68, 0x65, 0x20,
0x62, 0x6f, 0x72, 0x6f, 0x67, 0x6f, 0x76, 0x65,
0x73, 0x2c, 0x0a, 0x41, 0x6e, 0x64, 0x20, 0x74,
0x68, 0x65, 0x20, 0x6d, 0x6f, 0x6d, 0x65, 0x20,
0x72, 0x61, 0x74, 0x68, 0x73, 0x20, 0x6f, 0x75,
0x74, 0x67, 0x72, 0x61, 0x62, 0x65, 0x2e
}
};
static const size_t test_data_len[2] =
{
34U,
127U
};
static const unsigned char test_mac[2][16] =
{
{
0xa8, 0x06, 0x1d, 0xc1, 0x30, 0x51, 0x36, 0xc6,
0xc2, 0x2b, 0x8b, 0xaf, 0x0c, 0x01, 0x27, 0xa9
},
{
0x45, 0x41, 0x66, 0x9a, 0x7e, 0xaa, 0xee, 0x61,
0xe7, 0x08, 0xdc, 0x7c, 0xbc, 0xc5, 0xeb, 0x62
}
};
/* Make sure no other definition is already present. */
#undef ASSERT
#define ASSERT(cond, args) \
do \
{ \
if (!(cond)) \
{ \
if (verbose != 0) \
mbedtls_printf args; \
\
return -1; \
} \
} \
while (0)
int mbedtls_poly1305_self_test(int verbose)
{
unsigned char mac[16];
unsigned i;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
for (i = 0U; i < 2U; i++) {
if (verbose != 0) {
mbedtls_printf(" Poly1305 test %u ", i);
}
ret = mbedtls_poly1305_mac(test_keys[i],
test_data[i],
test_data_len[i],
mac);
ASSERT(0 == ret, ("error code: %i\n", ret));
ASSERT(0 == memcmp(mac, test_mac[i], 16U), ("failed (mac)\n"));
if (verbose != 0) {
mbedtls_printf("passed\n");
}
}
if (verbose != 0) {
mbedtls_printf("\n");
}
return 0;
}
#endif /* MBEDTLS_SELF_TEST */
#endif /* MBEDTLS_POLY1305_C */
View Git Blame Copy Permalink