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mbedtls/library/gcm.c
Valerio Setti d0eebc1f94 ccm/gcm: improve code maintainability 
Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
2023-11-20 15:17:53 +01:00

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/*
* NIST SP800-38D compliant GCM implementation
*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
*/
/*
* http://csrc.nist.gov/publications/nistpubs/800-38D/SP-800-38D.pdf
*
* See also:
* [MGV] http://csrc.nist.gov/groups/ST/toolkit/BCM/documents/proposedmodes/gcm/gcm-revised-spec.pdf
*
* We use the algorithm described as Shoup's method with 4-bit tables in
* [MGV] 4.1, pp. 12-13, to enhance speed without using too much memory.
*/
#include "common.h"
#if defined(MBEDTLS_GCM_C)
#include "mbedtls/gcm.h"
#include "mbedtls/platform.h"
#include "mbedtls/platform_util.h"
#include "mbedtls/error.h"
#include "mbedtls/constant_time.h"
#if !defined(MBEDTLS_CIPHER_C)
#include "block_cipher_internal.h"
#endif
#include <string.h>
#if defined(MBEDTLS_AESNI_C)
#include "aesni.h"
#endif
#if defined(MBEDTLS_AESCE_C)
#include "aesce.h"
#endif
#if !defined(MBEDTLS_GCM_ALT)
/*
* Initialize a context
*/
void mbedtls_gcm_init(mbedtls_gcm_context *ctx)
{
memset(ctx, 0, sizeof(mbedtls_gcm_context));
}
/*
* Precompute small multiples of H, that is set
* HH[i] || HL[i] = H times i,
* where i is seen as a field element as in [MGV], ie high-order bits
* correspond to low powers of P. The result is stored in the same way, that
* is the high-order bit of HH corresponds to P^0 and the low-order bit of HL
* corresponds to P^127.
*/
static int gcm_gen_table(mbedtls_gcm_context *ctx)
{
int ret, i, j;
uint64_t hi, lo;
uint64_t vl, vh;
unsigned char h[16];
memset(h, 0, 16);
#if defined(MBEDTLS_CIPHER_C)
size_t olen = 0;
ret = mbedtls_cipher_update(&ctx->cipher_ctx, h, 16, h, &olen);
#else
ret = mbedtls_block_cipher_encrypt(&ctx->block_cipher_ctx, h, h);
#endif
if (ret != 0) {
return ret;
}
/* pack h as two 64-bits ints, big-endian */
hi = MBEDTLS_GET_UINT32_BE(h, 0);
lo = MBEDTLS_GET_UINT32_BE(h, 4);
vh = (uint64_t) hi << 32 | lo;
hi = MBEDTLS_GET_UINT32_BE(h, 8);
lo = MBEDTLS_GET_UINT32_BE(h, 12);
vl = (uint64_t) hi << 32 | lo;
/* 8 = 1000 corresponds to 1 in GF(2^128) */
ctx->HL[8] = vl;
ctx->HH[8] = vh;
#if defined(MBEDTLS_AESNI_HAVE_CODE)
/* With CLMUL support, we need only h, not the rest of the table */
if (mbedtls_aesni_has_support(MBEDTLS_AESNI_CLMUL)) {
return 0;
}
#endif
#if defined(MBEDTLS_AESCE_HAVE_CODE)
if (MBEDTLS_AESCE_HAS_SUPPORT()) {
return 0;
}
#endif
/* 0 corresponds to 0 in GF(2^128) */
ctx->HH[0] = 0;
ctx->HL[0] = 0;
for (i = 4; i > 0; i >>= 1) {
uint32_t T = (vl & 1) * 0xe1000000U;
vl = (vh << 63) | (vl >> 1);
vh = (vh >> 1) ^ ((uint64_t) T << 32);
ctx->HL[i] = vl;
ctx->HH[i] = vh;
}
for (i = 2; i <= 8; i *= 2) {
uint64_t *HiL = ctx->HL + i, *HiH = ctx->HH + i;
vh = *HiH;
vl = *HiL;
for (j = 1; j < i; j++) {
HiH[j] = vh ^ ctx->HH[j];
HiL[j] = vl ^ ctx->HL[j];
}
}
return 0;
}
int mbedtls_gcm_setkey(mbedtls_gcm_context *ctx,
mbedtls_cipher_id_t cipher,
const unsigned char *key,
unsigned int keybits)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
if (keybits != 128 && keybits != 192 && keybits != 256) {
return MBEDTLS_ERR_GCM_BAD_INPUT;
}
#if defined(MBEDTLS_CIPHER_C)
const mbedtls_cipher_info_t *cipher_info;
cipher_info = mbedtls_cipher_info_from_values(cipher, keybits,
MBEDTLS_MODE_ECB);
if (cipher_info == NULL) {
return MBEDTLS_ERR_GCM_BAD_INPUT;
}
if (mbedtls_cipher_info_get_block_size(cipher_info) != 16) {
return MBEDTLS_ERR_GCM_BAD_INPUT;
}
mbedtls_cipher_free(&ctx->cipher_ctx);
if ((ret = mbedtls_cipher_setup(&ctx->cipher_ctx, cipher_info)) != 0) {
return ret;
}
if ((ret = mbedtls_cipher_setkey(&ctx->cipher_ctx, key, keybits,
MBEDTLS_ENCRYPT)) != 0) {
return ret;
}
#else
mbedtls_block_cipher_free(&ctx->block_cipher_ctx);
if ((ret = mbedtls_block_cipher_setup(&ctx->block_cipher_ctx, cipher)) != 0) {
return ret;
}
if ((ret = mbedtls_block_cipher_setkey(&ctx->block_cipher_ctx, key, keybits)) != 0) {
return ret;
}
#endif
if ((ret = gcm_gen_table(ctx)) != 0) {
return ret;
}
return 0;
}
/*
* Shoup's method for multiplication use this table with
* last4[x] = x times P^128
* where x and last4[x] are seen as elements of GF(2^128) as in [MGV]
*/
static const uint16_t last4[16] =
{
0x0000, 0x1c20, 0x3840, 0x2460,
0x7080, 0x6ca0, 0x48c0, 0x54e0,
0xe100, 0xfd20, 0xd940, 0xc560,
0x9180, 0x8da0, 0xa9c0, 0xb5e0
};
/*
* Sets output to x times H using the precomputed tables.
* x and output are seen as elements of GF(2^128) as in [MGV].
*/
static void gcm_mult(mbedtls_gcm_context *ctx, const unsigned char x[16],
unsigned char output[16])
{
int i = 0;
unsigned char lo, hi, rem;
uint64_t zh, zl;
#if defined(MBEDTLS_AESNI_HAVE_CODE)
if (mbedtls_aesni_has_support(MBEDTLS_AESNI_CLMUL)) {
unsigned char h[16];
/* mbedtls_aesni_gcm_mult needs big-endian input */
MBEDTLS_PUT_UINT32_BE(ctx->HH[8] >> 32, h, 0);
MBEDTLS_PUT_UINT32_BE(ctx->HH[8], h, 4);
MBEDTLS_PUT_UINT32_BE(ctx->HL[8] >> 32, h, 8);
MBEDTLS_PUT_UINT32_BE(ctx->HL[8], h, 12);
mbedtls_aesni_gcm_mult(output, x, h);
return;
}
#endif /* MBEDTLS_AESNI_HAVE_CODE */
#if defined(MBEDTLS_AESCE_HAVE_CODE)
if (MBEDTLS_AESCE_HAS_SUPPORT()) {
unsigned char h[16];
/* mbedtls_aesce_gcm_mult needs big-endian input */
MBEDTLS_PUT_UINT32_BE(ctx->HH[8] >> 32, h, 0);
MBEDTLS_PUT_UINT32_BE(ctx->HH[8], h, 4);
MBEDTLS_PUT_UINT32_BE(ctx->HL[8] >> 32, h, 8);
MBEDTLS_PUT_UINT32_BE(ctx->HL[8], h, 12);
mbedtls_aesce_gcm_mult(output, x, h);
return;
}
#endif
lo = x[15] & 0xf;
zh = ctx->HH[lo];
zl = ctx->HL[lo];
for (i = 15; i >= 0; i--) {
lo = x[i] & 0xf;
hi = (x[i] >> 4) & 0xf;
if (i != 15) {
rem = (unsigned char) zl & 0xf;
zl = (zh << 60) | (zl >> 4);
zh = (zh >> 4);
zh ^= (uint64_t) last4[rem] << 48;
zh ^= ctx->HH[lo];
zl ^= ctx->HL[lo];
}
rem = (unsigned char) zl & 0xf;
zl = (zh << 60) | (zl >> 4);
zh = (zh >> 4);
zh ^= (uint64_t) last4[rem] << 48;
zh ^= ctx->HH[hi];
zl ^= ctx->HL[hi];
}
MBEDTLS_PUT_UINT32_BE(zh >> 32, output, 0);
MBEDTLS_PUT_UINT32_BE(zh, output, 4);
MBEDTLS_PUT_UINT32_BE(zl >> 32, output, 8);
MBEDTLS_PUT_UINT32_BE(zl, output, 12);
}
int mbedtls_gcm_starts(mbedtls_gcm_context *ctx,
int mode,
const unsigned char *iv, size_t iv_len)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char work_buf[16];
const unsigned char *p;
size_t use_len;
uint64_t iv_bits;
#if defined(MBEDTLS_CIPHER_C)
size_t olen = 0;
#endif
/* IV is limited to 2^64 bits, so 2^61 bytes */
/* IV is not allowed to be zero length */
if (iv_len == 0 || (uint64_t) iv_len >> 61 != 0) {
return MBEDTLS_ERR_GCM_BAD_INPUT;
}
memset(ctx->y, 0x00, sizeof(ctx->y));
memset(ctx->buf, 0x00, sizeof(ctx->buf));
ctx->mode = mode;
ctx->len = 0;
ctx->add_len = 0;
if (iv_len == 12) {
memcpy(ctx->y, iv, iv_len);
ctx->y[15] = 1;
} else {
memset(work_buf, 0x00, 16);
iv_bits = (uint64_t) iv_len * 8;
MBEDTLS_PUT_UINT64_BE(iv_bits, work_buf, 8);
p = iv;
while (iv_len > 0) {
use_len = (iv_len < 16) ? iv_len : 16;
mbedtls_xor(ctx->y, ctx->y, p, use_len);
gcm_mult(ctx, ctx->y, ctx->y);
iv_len -= use_len;
p += use_len;
}
mbedtls_xor(ctx->y, ctx->y, work_buf, 16);
gcm_mult(ctx, ctx->y, ctx->y);
}
#if defined(MBEDTLS_CIPHER_C)
ret = mbedtls_cipher_update(&ctx->cipher_ctx, ctx->y, 16, ctx->base_ectr, &olen);
#else
ret = mbedtls_block_cipher_encrypt(&ctx->block_cipher_ctx, ctx->y, ctx->base_ectr);
#endif
if (ret != 0) {
return ret;
}
return 0;
}
/**
* mbedtls_gcm_context::buf contains the partial state of the computation of
* the authentication tag.
* mbedtls_gcm_context::add_len and mbedtls_gcm_context::len indicate
* different stages of the computation:
* * len == 0 && add_len == 0: initial state
* * len == 0 && add_len % 16 != 0: the first `add_len % 16` bytes have
* a partial block of AD that has been
* xored in but not yet multiplied in.
* * len == 0 && add_len % 16 == 0: the authentication tag is correct if
* the data ends now.
* * len % 16 != 0: the first `len % 16` bytes have
* a partial block of ciphertext that has
* been xored in but not yet multiplied in.
* * len > 0 && len % 16 == 0: the authentication tag is correct if
* the data ends now.
*/
int mbedtls_gcm_update_ad(mbedtls_gcm_context *ctx,
const unsigned char *add, size_t add_len)
{
const unsigned char *p;
size_t use_len, offset;
/* IV is limited to 2^64 bits, so 2^61 bytes */
if ((uint64_t) add_len >> 61 != 0) {
return MBEDTLS_ERR_GCM_BAD_INPUT;
}
offset = ctx->add_len % 16;
p = add;
if (offset != 0) {
use_len = 16 - offset;
if (use_len > add_len) {
use_len = add_len;
}
mbedtls_xor(ctx->buf + offset, ctx->buf + offset, p, use_len);
if (offset + use_len == 16) {
gcm_mult(ctx, ctx->buf, ctx->buf);
}
ctx->add_len += use_len;
add_len -= use_len;
p += use_len;
}
ctx->add_len += add_len;
while (add_len >= 16) {
mbedtls_xor(ctx->buf, ctx->buf, p, 16);
gcm_mult(ctx, ctx->buf, ctx->buf);
add_len -= 16;
p += 16;
}
if (add_len > 0) {
mbedtls_xor(ctx->buf, ctx->buf, p, add_len);
}
return 0;
}
/* Increment the counter. */
static void gcm_incr(unsigned char y[16])
{
size_t i;
for (i = 16; i > 12; i--) {
if (++y[i - 1] != 0) {
break;
}
}
}
/* Calculate and apply the encryption mask. Process use_len bytes of data,
* starting at position offset in the mask block. */
static int gcm_mask(mbedtls_gcm_context *ctx,
unsigned char ectr[16],
size_t offset, size_t use_len,
const unsigned char *input,
unsigned char *output)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
#if defined(MBEDTLS_CIPHER_C)
size_t olen = 0;
ret = mbedtls_cipher_update(&ctx->cipher_ctx, ctx->y, 16, ectr, &olen);
#else
ret = mbedtls_block_cipher_encrypt(&ctx->block_cipher_ctx, ctx->y, ectr);
#endif
if (ret != 0) {
mbedtls_platform_zeroize(ectr, 16);
return ret;
}
if (ctx->mode == MBEDTLS_GCM_DECRYPT) {
mbedtls_xor(ctx->buf + offset, ctx->buf + offset, input, use_len);
}
mbedtls_xor(output, ectr + offset, input, use_len);
if (ctx->mode == MBEDTLS_GCM_ENCRYPT) {
mbedtls_xor(ctx->buf + offset, ctx->buf + offset, output, use_len);
}
return 0;
}
int mbedtls_gcm_update(mbedtls_gcm_context *ctx,
const unsigned char *input, size_t input_length,
unsigned char *output, size_t output_size,
size_t *output_length)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
const unsigned char *p = input;
unsigned char *out_p = output;
size_t offset;
unsigned char ectr[16] = { 0 };
if (output_size < input_length) {
return MBEDTLS_ERR_GCM_BUFFER_TOO_SMALL;
}
*output_length = input_length;
/* Exit early if input_length==0 so that we don't do any pointer arithmetic
* on a potentially null pointer.
* Returning early also means that the last partial block of AD remains
* untouched for mbedtls_gcm_finish */
if (input_length == 0) {
return 0;
}
if (output > input && (size_t) (output - input) < input_length) {
return MBEDTLS_ERR_GCM_BAD_INPUT;
}
/* Total length is restricted to 2^39 - 256 bits, ie 2^36 - 2^5 bytes
* Also check for possible overflow */
if (ctx->len + input_length < ctx->len ||
(uint64_t) ctx->len + input_length > 0xFFFFFFFE0ull) {
return MBEDTLS_ERR_GCM_BAD_INPUT;
}
if (ctx->len == 0 && ctx->add_len % 16 != 0) {
gcm_mult(ctx, ctx->buf, ctx->buf);
}
offset = ctx->len % 16;
if (offset != 0) {
size_t use_len = 16 - offset;
if (use_len > input_length) {
use_len = input_length;
}
if ((ret = gcm_mask(ctx, ectr, offset, use_len, p, out_p)) != 0) {
return ret;
}
if (offset + use_len == 16) {
gcm_mult(ctx, ctx->buf, ctx->buf);
}
ctx->len += use_len;
input_length -= use_len;
p += use_len;
out_p += use_len;
}
ctx->len += input_length;
while (input_length >= 16) {
gcm_incr(ctx->y);
if ((ret = gcm_mask(ctx, ectr, 0, 16, p, out_p)) != 0) {
return ret;
}
gcm_mult(ctx, ctx->buf, ctx->buf);
input_length -= 16;
p += 16;
out_p += 16;
}
if (input_length > 0) {
gcm_incr(ctx->y);
if ((ret = gcm_mask(ctx, ectr, 0, input_length, p, out_p)) != 0) {
return ret;
}
}
mbedtls_platform_zeroize(ectr, sizeof(ectr));
return 0;
}
int mbedtls_gcm_finish(mbedtls_gcm_context *ctx,
unsigned char *output, size_t output_size,
size_t *output_length,
unsigned char *tag, size_t tag_len)
{
unsigned char work_buf[16];
uint64_t orig_len;
uint64_t orig_add_len;
/* We never pass any output in finish(). The output parameter exists only
* for the sake of alternative implementations. */
(void) output;
(void) output_size;
*output_length = 0;
orig_len = ctx->len * 8;
orig_add_len = ctx->add_len * 8;
if (ctx->len == 0 && ctx->add_len % 16 != 0) {
gcm_mult(ctx, ctx->buf, ctx->buf);
}
if (tag_len > 16 || tag_len < 4) {
return MBEDTLS_ERR_GCM_BAD_INPUT;
}
if (ctx->len % 16 != 0) {
gcm_mult(ctx, ctx->buf, ctx->buf);
}
memcpy(tag, ctx->base_ectr, tag_len);
if (orig_len || orig_add_len) {
memset(work_buf, 0x00, 16);
MBEDTLS_PUT_UINT32_BE((orig_add_len >> 32), work_buf, 0);
MBEDTLS_PUT_UINT32_BE((orig_add_len), work_buf, 4);
MBEDTLS_PUT_UINT32_BE((orig_len >> 32), work_buf, 8);
MBEDTLS_PUT_UINT32_BE((orig_len), work_buf, 12);
mbedtls_xor(ctx->buf, ctx->buf, work_buf, 16);
gcm_mult(ctx, ctx->buf, ctx->buf);
mbedtls_xor(tag, tag, ctx->buf, tag_len);
}
return 0;
}
int mbedtls_gcm_crypt_and_tag(mbedtls_gcm_context *ctx,
int mode,
size_t length,
const unsigned char *iv,
size_t iv_len,
const unsigned char *add,
size_t add_len,
const unsigned char *input,
unsigned char *output,
size_t tag_len,
unsigned char *tag)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t olen;
if ((ret = mbedtls_gcm_starts(ctx, mode, iv, iv_len)) != 0) {
return ret;
}
if ((ret = mbedtls_gcm_update_ad(ctx, add, add_len)) != 0) {
return ret;
}
if ((ret = mbedtls_gcm_update(ctx, input, length,
output, length, &olen)) != 0) {
return ret;
}
if ((ret = mbedtls_gcm_finish(ctx, NULL, 0, &olen, tag, tag_len)) != 0) {
return ret;
}
return 0;
}
int mbedtls_gcm_auth_decrypt(mbedtls_gcm_context *ctx,
size_t length,
const unsigned char *iv,
size_t iv_len,
const unsigned char *add,
size_t add_len,
const unsigned char *tag,
size_t tag_len,
const unsigned char *input,
unsigned char *output)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char check_tag[16];
int diff;
if ((ret = mbedtls_gcm_crypt_and_tag(ctx, MBEDTLS_GCM_DECRYPT, length,
iv, iv_len, add, add_len,
input, output, tag_len, check_tag)) != 0) {
return ret;
}
/* Check tag in "constant-time" */
diff = mbedtls_ct_memcmp(tag, check_tag, tag_len);
if (diff != 0) {
mbedtls_platform_zeroize(output, length);
return MBEDTLS_ERR_GCM_AUTH_FAILED;
}
return 0;
}
void mbedtls_gcm_free(mbedtls_gcm_context *ctx)
{
if (ctx == NULL) {
return;
}
#if defined(MBEDTLS_CIPHER_C)
mbedtls_cipher_free(&ctx->cipher_ctx);
#else
mbedtls_block_cipher_free(&ctx->block_cipher_ctx);
#endif
mbedtls_platform_zeroize(ctx, sizeof(mbedtls_gcm_context));
}
#endif /* !MBEDTLS_GCM_ALT */
#if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
/*
* AES-GCM test vectors from:
*
* http://csrc.nist.gov/groups/STM/cavp/documents/mac/gcmtestvectors.zip
*/
#define MAX_TESTS 6
static const int key_index_test_data[MAX_TESTS] =
{ 0, 0, 1, 1, 1, 1 };
static const unsigned char key_test_data[][32] =
{
{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
{ 0xfe, 0xff, 0xe9, 0x92, 0x86, 0x65, 0x73, 0x1c,
0x6d, 0x6a, 0x8f, 0x94, 0x67, 0x30, 0x83, 0x08,
0xfe, 0xff, 0xe9, 0x92, 0x86, 0x65, 0x73, 0x1c,
0x6d, 0x6a, 0x8f, 0x94, 0x67, 0x30, 0x83, 0x08 },
};
static const size_t iv_len_test_data[MAX_TESTS] =
{ 12, 12, 12, 12, 8, 60 };
static const int iv_index_test_data[MAX_TESTS] =
{ 0, 0, 1, 1, 1, 2 };
static const unsigned char iv_test_data[][64] =
{
{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00 },
{ 0xca, 0xfe, 0xba, 0xbe, 0xfa, 0xce, 0xdb, 0xad,
0xde, 0xca, 0xf8, 0x88 },
{ 0x93, 0x13, 0x22, 0x5d, 0xf8, 0x84, 0x06, 0xe5,
0x55, 0x90, 0x9c, 0x5a, 0xff, 0x52, 0x69, 0xaa,
0x6a, 0x7a, 0x95, 0x38, 0x53, 0x4f, 0x7d, 0xa1,
0xe4, 0xc3, 0x03, 0xd2, 0xa3, 0x18, 0xa7, 0x28,
0xc3, 0xc0, 0xc9, 0x51, 0x56, 0x80, 0x95, 0x39,
0xfc, 0xf0, 0xe2, 0x42, 0x9a, 0x6b, 0x52, 0x54,
0x16, 0xae, 0xdb, 0xf5, 0xa0, 0xde, 0x6a, 0x57,
0xa6, 0x37, 0xb3, 0x9b },
};
static const size_t add_len_test_data[MAX_TESTS] =
{ 0, 0, 0, 20, 20, 20 };
static const int add_index_test_data[MAX_TESTS] =
{ 0, 0, 0, 1, 1, 1 };
static const unsigned char additional_test_data[][64] =
{
{ 0x00 },
{ 0xfe, 0xed, 0xfa, 0xce, 0xde, 0xad, 0xbe, 0xef,
0xfe, 0xed, 0xfa, 0xce, 0xde, 0xad, 0xbe, 0xef,
0xab, 0xad, 0xda, 0xd2 },
};
static const size_t pt_len_test_data[MAX_TESTS] =
{ 0, 16, 64, 60, 60, 60 };
static const int pt_index_test_data[MAX_TESTS] =
{ 0, 0, 1, 1, 1, 1 };
static const unsigned char pt_test_data[][64] =
{
{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
{ 0xd9, 0x31, 0x32, 0x25, 0xf8, 0x84, 0x06, 0xe5,
0xa5, 0x59, 0x09, 0xc5, 0xaf, 0xf5, 0x26, 0x9a,
0x86, 0xa7, 0xa9, 0x53, 0x15, 0x34, 0xf7, 0xda,
0x2e, 0x4c, 0x30, 0x3d, 0x8a, 0x31, 0x8a, 0x72,
0x1c, 0x3c, 0x0c, 0x95, 0x95, 0x68, 0x09, 0x53,
0x2f, 0xcf, 0x0e, 0x24, 0x49, 0xa6, 0xb5, 0x25,
0xb1, 0x6a, 0xed, 0xf5, 0xaa, 0x0d, 0xe6, 0x57,
0xba, 0x63, 0x7b, 0x39, 0x1a, 0xaf, 0xd2, 0x55 },
};
static const unsigned char ct_test_data[][64] =
{
{ 0x00 },
{ 0x03, 0x88, 0xda, 0xce, 0x60, 0xb6, 0xa3, 0x92,
0xf3, 0x28, 0xc2, 0xb9, 0x71, 0xb2, 0xfe, 0x78 },
{ 0x42, 0x83, 0x1e, 0xc2, 0x21, 0x77, 0x74, 0x24,
0x4b, 0x72, 0x21, 0xb7, 0x84, 0xd0, 0xd4, 0x9c,
0xe3, 0xaa, 0x21, 0x2f, 0x2c, 0x02, 0xa4, 0xe0,
0x35, 0xc1, 0x7e, 0x23, 0x29, 0xac, 0xa1, 0x2e,
0x21, 0xd5, 0x14, 0xb2, 0x54, 0x66, 0x93, 0x1c,
0x7d, 0x8f, 0x6a, 0x5a, 0xac, 0x84, 0xaa, 0x05,
0x1b, 0xa3, 0x0b, 0x39, 0x6a, 0x0a, 0xac, 0x97,
0x3d, 0x58, 0xe0, 0x91, 0x47, 0x3f, 0x59, 0x85 },
{ 0x42, 0x83, 0x1e, 0xc2, 0x21, 0x77, 0x74, 0x24,
0x4b, 0x72, 0x21, 0xb7, 0x84, 0xd0, 0xd4, 0x9c,
0xe3, 0xaa, 0x21, 0x2f, 0x2c, 0x02, 0xa4, 0xe0,
0x35, 0xc1, 0x7e, 0x23, 0x29, 0xac, 0xa1, 0x2e,
0x21, 0xd5, 0x14, 0xb2, 0x54, 0x66, 0x93, 0x1c,
0x7d, 0x8f, 0x6a, 0x5a, 0xac, 0x84, 0xaa, 0x05,
0x1b, 0xa3, 0x0b, 0x39, 0x6a, 0x0a, 0xac, 0x97,
0x3d, 0x58, 0xe0, 0x91 },
{ 0x61, 0x35, 0x3b, 0x4c, 0x28, 0x06, 0x93, 0x4a,
0x77, 0x7f, 0xf5, 0x1f, 0xa2, 0x2a, 0x47, 0x55,
0x69, 0x9b, 0x2a, 0x71, 0x4f, 0xcd, 0xc6, 0xf8,
0x37, 0x66, 0xe5, 0xf9, 0x7b, 0x6c, 0x74, 0x23,
0x73, 0x80, 0x69, 0x00, 0xe4, 0x9f, 0x24, 0xb2,
0x2b, 0x09, 0x75, 0x44, 0xd4, 0x89, 0x6b, 0x42,
0x49, 0x89, 0xb5, 0xe1, 0xeb, 0xac, 0x0f, 0x07,
0xc2, 0x3f, 0x45, 0x98 },
{ 0x8c, 0xe2, 0x49, 0x98, 0x62, 0x56, 0x15, 0xb6,
0x03, 0xa0, 0x33, 0xac, 0xa1, 0x3f, 0xb8, 0x94,
0xbe, 0x91, 0x12, 0xa5, 0xc3, 0xa2, 0x11, 0xa8,
0xba, 0x26, 0x2a, 0x3c, 0xca, 0x7e, 0x2c, 0xa7,
0x01, 0xe4, 0xa9, 0xa4, 0xfb, 0xa4, 0x3c, 0x90,
0xcc, 0xdc, 0xb2, 0x81, 0xd4, 0x8c, 0x7c, 0x6f,
0xd6, 0x28, 0x75, 0xd2, 0xac, 0xa4, 0x17, 0x03,
0x4c, 0x34, 0xae, 0xe5 },
#if !defined(MBEDTLS_AES_ONLY_128_BIT_KEY_LENGTH)
{ 0x00 },
{ 0x98, 0xe7, 0x24, 0x7c, 0x07, 0xf0, 0xfe, 0x41,
0x1c, 0x26, 0x7e, 0x43, 0x84, 0xb0, 0xf6, 0x00 },
{ 0x39, 0x80, 0xca, 0x0b, 0x3c, 0x00, 0xe8, 0x41,
0xeb, 0x06, 0xfa, 0xc4, 0x87, 0x2a, 0x27, 0x57,
0x85, 0x9e, 0x1c, 0xea, 0xa6, 0xef, 0xd9, 0x84,
0x62, 0x85, 0x93, 0xb4, 0x0c, 0xa1, 0xe1, 0x9c,
0x7d, 0x77, 0x3d, 0x00, 0xc1, 0x44, 0xc5, 0x25,
0xac, 0x61, 0x9d, 0x18, 0xc8, 0x4a, 0x3f, 0x47,
0x18, 0xe2, 0x44, 0x8b, 0x2f, 0xe3, 0x24, 0xd9,
0xcc, 0xda, 0x27, 0x10, 0xac, 0xad, 0xe2, 0x56 },
{ 0x39, 0x80, 0xca, 0x0b, 0x3c, 0x00, 0xe8, 0x41,
0xeb, 0x06, 0xfa, 0xc4, 0x87, 0x2a, 0x27, 0x57,
0x85, 0x9e, 0x1c, 0xea, 0xa6, 0xef, 0xd9, 0x84,
0x62, 0x85, 0x93, 0xb4, 0x0c, 0xa1, 0xe1, 0x9c,
0x7d, 0x77, 0x3d, 0x00, 0xc1, 0x44, 0xc5, 0x25,
0xac, 0x61, 0x9d, 0x18, 0xc8, 0x4a, 0x3f, 0x47,
0x18, 0xe2, 0x44, 0x8b, 0x2f, 0xe3, 0x24, 0xd9,
0xcc, 0xda, 0x27, 0x10 },
{ 0x0f, 0x10, 0xf5, 0x99, 0xae, 0x14, 0xa1, 0x54,
0xed, 0x24, 0xb3, 0x6e, 0x25, 0x32, 0x4d, 0xb8,
0xc5, 0x66, 0x63, 0x2e, 0xf2, 0xbb, 0xb3, 0x4f,
0x83, 0x47, 0x28, 0x0f, 0xc4, 0x50, 0x70, 0x57,
0xfd, 0xdc, 0x29, 0xdf, 0x9a, 0x47, 0x1f, 0x75,
0xc6, 0x65, 0x41, 0xd4, 0xd4, 0xda, 0xd1, 0xc9,
0xe9, 0x3a, 0x19, 0xa5, 0x8e, 0x8b, 0x47, 0x3f,
0xa0, 0xf0, 0x62, 0xf7 },
{ 0xd2, 0x7e, 0x88, 0x68, 0x1c, 0xe3, 0x24, 0x3c,
0x48, 0x30, 0x16, 0x5a, 0x8f, 0xdc, 0xf9, 0xff,
0x1d, 0xe9, 0xa1, 0xd8, 0xe6, 0xb4, 0x47, 0xef,
0x6e, 0xf7, 0xb7, 0x98, 0x28, 0x66, 0x6e, 0x45,
0x81, 0xe7, 0x90, 0x12, 0xaf, 0x34, 0xdd, 0xd9,
0xe2, 0xf0, 0x37, 0x58, 0x9b, 0x29, 0x2d, 0xb3,
0xe6, 0x7c, 0x03, 0x67, 0x45, 0xfa, 0x22, 0xe7,
0xe9, 0xb7, 0x37, 0x3b },
{ 0x00 },
{ 0xce, 0xa7, 0x40, 0x3d, 0x4d, 0x60, 0x6b, 0x6e,
0x07, 0x4e, 0xc5, 0xd3, 0xba, 0xf3, 0x9d, 0x18 },
{ 0x52, 0x2d, 0xc1, 0xf0, 0x99, 0x56, 0x7d, 0x07,
0xf4, 0x7f, 0x37, 0xa3, 0x2a, 0x84, 0x42, 0x7d,
0x64, 0x3a, 0x8c, 0xdc, 0xbf, 0xe5, 0xc0, 0xc9,
0x75, 0x98, 0xa2, 0xbd, 0x25, 0x55, 0xd1, 0xaa,
0x8c, 0xb0, 0x8e, 0x48, 0x59, 0x0d, 0xbb, 0x3d,
0xa7, 0xb0, 0x8b, 0x10, 0x56, 0x82, 0x88, 0x38,
0xc5, 0xf6, 0x1e, 0x63, 0x93, 0xba, 0x7a, 0x0a,
0xbc, 0xc9, 0xf6, 0x62, 0x89, 0x80, 0x15, 0xad },
{ 0x52, 0x2d, 0xc1, 0xf0, 0x99, 0x56, 0x7d, 0x07,
0xf4, 0x7f, 0x37, 0xa3, 0x2a, 0x84, 0x42, 0x7d,
0x64, 0x3a, 0x8c, 0xdc, 0xbf, 0xe5, 0xc0, 0xc9,
0x75, 0x98, 0xa2, 0xbd, 0x25, 0x55, 0xd1, 0xaa,
0x8c, 0xb0, 0x8e, 0x48, 0x59, 0x0d, 0xbb, 0x3d,
0xa7, 0xb0, 0x8b, 0x10, 0x56, 0x82, 0x88, 0x38,
0xc5, 0xf6, 0x1e, 0x63, 0x93, 0xba, 0x7a, 0x0a,
0xbc, 0xc9, 0xf6, 0x62 },
{ 0xc3, 0x76, 0x2d, 0xf1, 0xca, 0x78, 0x7d, 0x32,
0xae, 0x47, 0xc1, 0x3b, 0xf1, 0x98, 0x44, 0xcb,
0xaf, 0x1a, 0xe1, 0x4d, 0x0b, 0x97, 0x6a, 0xfa,
0xc5, 0x2f, 0xf7, 0xd7, 0x9b, 0xba, 0x9d, 0xe0,
0xfe, 0xb5, 0x82, 0xd3, 0x39, 0x34, 0xa4, 0xf0,
0x95, 0x4c, 0xc2, 0x36, 0x3b, 0xc7, 0x3f, 0x78,
0x62, 0xac, 0x43, 0x0e, 0x64, 0xab, 0xe4, 0x99,
0xf4, 0x7c, 0x9b, 0x1f },
{ 0x5a, 0x8d, 0xef, 0x2f, 0x0c, 0x9e, 0x53, 0xf1,
0xf7, 0x5d, 0x78, 0x53, 0x65, 0x9e, 0x2a, 0x20,
0xee, 0xb2, 0xb2, 0x2a, 0xaf, 0xde, 0x64, 0x19,
0xa0, 0x58, 0xab, 0x4f, 0x6f, 0x74, 0x6b, 0xf4,
0x0f, 0xc0, 0xc3, 0xb7, 0x80, 0xf2, 0x44, 0x45,
0x2d, 0xa3, 0xeb, 0xf1, 0xc5, 0xd8, 0x2c, 0xde,
0xa2, 0x41, 0x89, 0x97, 0x20, 0x0e, 0xf8, 0x2e,
0x44, 0xae, 0x7e, 0x3f },
#endif /* !MBEDTLS_AES_ONLY_128_BIT_KEY_LENGTH */
};
static const unsigned char tag_test_data[][16] =
{
{ 0x58, 0xe2, 0xfc, 0xce, 0xfa, 0x7e, 0x30, 0x61,
0x36, 0x7f, 0x1d, 0x57, 0xa4, 0xe7, 0x45, 0x5a },
{ 0xab, 0x6e, 0x47, 0xd4, 0x2c, 0xec, 0x13, 0xbd,
0xf5, 0x3a, 0x67, 0xb2, 0x12, 0x57, 0xbd, 0xdf },
{ 0x4d, 0x5c, 0x2a, 0xf3, 0x27, 0xcd, 0x64, 0xa6,
0x2c, 0xf3, 0x5a, 0xbd, 0x2b, 0xa6, 0xfa, 0xb4 },
{ 0x5b, 0xc9, 0x4f, 0xbc, 0x32, 0x21, 0xa5, 0xdb,
0x94, 0xfa, 0xe9, 0x5a, 0xe7, 0x12, 0x1a, 0x47 },
{ 0x36, 0x12, 0xd2, 0xe7, 0x9e, 0x3b, 0x07, 0x85,
0x56, 0x1b, 0xe1, 0x4a, 0xac, 0xa2, 0xfc, 0xcb },
{ 0x61, 0x9c, 0xc5, 0xae, 0xff, 0xfe, 0x0b, 0xfa,
0x46, 0x2a, 0xf4, 0x3c, 0x16, 0x99, 0xd0, 0x50 },
#if !defined(MBEDTLS_AES_ONLY_128_BIT_KEY_LENGTH)
{ 0xcd, 0x33, 0xb2, 0x8a, 0xc7, 0x73, 0xf7, 0x4b,
0xa0, 0x0e, 0xd1, 0xf3, 0x12, 0x57, 0x24, 0x35 },
{ 0x2f, 0xf5, 0x8d, 0x80, 0x03, 0x39, 0x27, 0xab,
0x8e, 0xf4, 0xd4, 0x58, 0x75, 0x14, 0xf0, 0xfb },
{ 0x99, 0x24, 0xa7, 0xc8, 0x58, 0x73, 0x36, 0xbf,
0xb1, 0x18, 0x02, 0x4d, 0xb8, 0x67, 0x4a, 0x14 },
{ 0x25, 0x19, 0x49, 0x8e, 0x80, 0xf1, 0x47, 0x8f,
0x37, 0xba, 0x55, 0xbd, 0x6d, 0x27, 0x61, 0x8c },
{ 0x65, 0xdc, 0xc5, 0x7f, 0xcf, 0x62, 0x3a, 0x24,
0x09, 0x4f, 0xcc, 0xa4, 0x0d, 0x35, 0x33, 0xf8 },
{ 0xdc, 0xf5, 0x66, 0xff, 0x29, 0x1c, 0x25, 0xbb,
0xb8, 0x56, 0x8f, 0xc3, 0xd3, 0x76, 0xa6, 0xd9 },
{ 0x53, 0x0f, 0x8a, 0xfb, 0xc7, 0x45, 0x36, 0xb9,
0xa9, 0x63, 0xb4, 0xf1, 0xc4, 0xcb, 0x73, 0x8b },
{ 0xd0, 0xd1, 0xc8, 0xa7, 0x99, 0x99, 0x6b, 0xf0,
0x26, 0x5b, 0x98, 0xb5, 0xd4, 0x8a, 0xb9, 0x19 },
{ 0xb0, 0x94, 0xda, 0xc5, 0xd9, 0x34, 0x71, 0xbd,
0xec, 0x1a, 0x50, 0x22, 0x70, 0xe3, 0xcc, 0x6c },
{ 0x76, 0xfc, 0x6e, 0xce, 0x0f, 0x4e, 0x17, 0x68,
0xcd, 0xdf, 0x88, 0x53, 0xbb, 0x2d, 0x55, 0x1b },
{ 0x3a, 0x33, 0x7d, 0xbf, 0x46, 0xa7, 0x92, 0xc4,
0x5e, 0x45, 0x49, 0x13, 0xfe, 0x2e, 0xa8, 0xf2 },
{ 0xa4, 0x4a, 0x82, 0x66, 0xee, 0x1c, 0x8e, 0xb0,
0xc8, 0xb5, 0xd4, 0xcf, 0x5a, 0xe9, 0xf1, 0x9a },
#endif /* !MBEDTLS_AES_ONLY_128_BIT_KEY_LENGTH */
};
int mbedtls_gcm_self_test(int verbose)
{
mbedtls_gcm_context ctx;
unsigned char buf[64];
unsigned char tag_buf[16];
int i, j, ret;
mbedtls_cipher_id_t cipher = MBEDTLS_CIPHER_ID_AES;
size_t olen;
if (verbose != 0) {
#if defined(MBEDTLS_GCM_ALT)
mbedtls_printf(" GCM note: alternative implementation.\n");
#else /* MBEDTLS_GCM_ALT */
#if defined(MBEDTLS_AESNI_HAVE_CODE)
if (mbedtls_aesni_has_support(MBEDTLS_AESNI_CLMUL)) {
mbedtls_printf(" GCM note: using AESNI.\n");
} else
#endif
#if defined(MBEDTLS_AESCE_HAVE_CODE)
if (MBEDTLS_AESCE_HAS_SUPPORT()) {
mbedtls_printf(" GCM note: using AESCE.\n");
} else
#endif
mbedtls_printf(" GCM note: built-in implementation.\n");
#endif /* MBEDTLS_GCM_ALT */
}
static const int loop_limit =
(sizeof(ct_test_data) / sizeof(*ct_test_data)) / MAX_TESTS;
for (j = 0; j < loop_limit; j++) {
int key_len = 128 + 64 * j;
for (i = 0; i < MAX_TESTS; i++) {
if (verbose != 0) {
mbedtls_printf(" AES-GCM-%3d #%d (%s): ",
key_len, i, "enc");
}
mbedtls_gcm_init(&ctx);
ret = mbedtls_gcm_setkey(&ctx, cipher,
key_test_data[key_index_test_data[i]],
key_len);
/*
* AES-192 is an optional feature that may be unavailable when
* there is an alternative underlying implementation i.e. when
* MBEDTLS_AES_ALT is defined.
*/
if (ret == MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED && key_len == 192) {
mbedtls_printf("skipped\n");
break;
} else if (ret != 0) {
goto exit;
}
ret = mbedtls_gcm_crypt_and_tag(&ctx, MBEDTLS_GCM_ENCRYPT,
pt_len_test_data[i],
iv_test_data[iv_index_test_data[i]],
iv_len_test_data[i],
additional_test_data[add_index_test_data[i]],
add_len_test_data[i],
pt_test_data[pt_index_test_data[i]],
buf, 16, tag_buf);
#if defined(MBEDTLS_GCM_ALT)
/* Allow alternative implementations to only support 12-byte nonces. */
if (ret == MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED &&
iv_len_test_data[i] != 12) {
mbedtls_printf("skipped\n");
break;
}
#endif /* defined(MBEDTLS_GCM_ALT) */
if (ret != 0) {
goto exit;
}
if (memcmp(buf, ct_test_data[j * 6 + i],
pt_len_test_data[i]) != 0 ||
memcmp(tag_buf, tag_test_data[j * 6 + i], 16) != 0) {
ret = 1;
goto exit;
}
mbedtls_gcm_free(&ctx);
if (verbose != 0) {
mbedtls_printf("passed\n");
}
mbedtls_gcm_init(&ctx);
if (verbose != 0) {
mbedtls_printf(" AES-GCM-%3d #%d (%s): ",
key_len, i, "dec");
}
ret = mbedtls_gcm_setkey(&ctx, cipher,
key_test_data[key_index_test_data[i]],
key_len);
if (ret != 0) {
goto exit;
}
ret = mbedtls_gcm_crypt_and_tag(&ctx, MBEDTLS_GCM_DECRYPT,
pt_len_test_data[i],
iv_test_data[iv_index_test_data[i]],
iv_len_test_data[i],
additional_test_data[add_index_test_data[i]],
add_len_test_data[i],
ct_test_data[j * 6 + i], buf, 16, tag_buf);
if (ret != 0) {
goto exit;
}
if (memcmp(buf, pt_test_data[pt_index_test_data[i]],
pt_len_test_data[i]) != 0 ||
memcmp(tag_buf, tag_test_data[j * 6 + i], 16) != 0) {
ret = 1;
goto exit;
}
mbedtls_gcm_free(&ctx);
if (verbose != 0) {
mbedtls_printf("passed\n");
}
mbedtls_gcm_init(&ctx);
if (verbose != 0) {
mbedtls_printf(" AES-GCM-%3d #%d split (%s): ",
key_len, i, "enc");
}
ret = mbedtls_gcm_setkey(&ctx, cipher,
key_test_data[key_index_test_data[i]],
key_len);
if (ret != 0) {
goto exit;
}
ret = mbedtls_gcm_starts(&ctx, MBEDTLS_GCM_ENCRYPT,
iv_test_data[iv_index_test_data[i]],
iv_len_test_data[i]);
if (ret != 0) {
goto exit;
}
ret = mbedtls_gcm_update_ad(&ctx,
additional_test_data[add_index_test_data[i]],
add_len_test_data[i]);
if (ret != 0) {
goto exit;
}
if (pt_len_test_data[i] > 32) {
size_t rest_len = pt_len_test_data[i] - 32;
ret = mbedtls_gcm_update(&ctx,
pt_test_data[pt_index_test_data[i]],
32,
buf, sizeof(buf), &olen);
if (ret != 0) {
goto exit;
}
if (olen != 32) {
goto exit;
}
ret = mbedtls_gcm_update(&ctx,
pt_test_data[pt_index_test_data[i]] + 32,
rest_len,
buf + 32, sizeof(buf) - 32, &olen);
if (ret != 0) {
goto exit;
}
if (olen != rest_len) {
goto exit;
}
} else {
ret = mbedtls_gcm_update(&ctx,
pt_test_data[pt_index_test_data[i]],
pt_len_test_data[i],
buf, sizeof(buf), &olen);
if (ret != 0) {
goto exit;
}
if (olen != pt_len_test_data[i]) {
goto exit;
}
}
ret = mbedtls_gcm_finish(&ctx, NULL, 0, &olen, tag_buf, 16);
if (ret != 0) {
goto exit;
}
if (memcmp(buf, ct_test_data[j * 6 + i],
pt_len_test_data[i]) != 0 ||
memcmp(tag_buf, tag_test_data[j * 6 + i], 16) != 0) {
ret = 1;
goto exit;
}
mbedtls_gcm_free(&ctx);
if (verbose != 0) {
mbedtls_printf("passed\n");
}
mbedtls_gcm_init(&ctx);
if (verbose != 0) {
mbedtls_printf(" AES-GCM-%3d #%d split (%s): ",
key_len, i, "dec");
}
ret = mbedtls_gcm_setkey(&ctx, cipher,
key_test_data[key_index_test_data[i]],
key_len);
if (ret != 0) {
goto exit;
}
ret = mbedtls_gcm_starts(&ctx, MBEDTLS_GCM_DECRYPT,
iv_test_data[iv_index_test_data[i]],
iv_len_test_data[i]);
if (ret != 0) {
goto exit;
}
ret = mbedtls_gcm_update_ad(&ctx,
additional_test_data[add_index_test_data[i]],
add_len_test_data[i]);
if (ret != 0) {
goto exit;
}
if (pt_len_test_data[i] > 32) {
size_t rest_len = pt_len_test_data[i] - 32;
ret = mbedtls_gcm_update(&ctx,
ct_test_data[j * 6 + i], 32,
buf, sizeof(buf), &olen);
if (ret != 0) {
goto exit;
}
if (olen != 32) {
goto exit;
}
ret = mbedtls_gcm_update(&ctx,
ct_test_data[j * 6 + i] + 32,
rest_len,
buf + 32, sizeof(buf) - 32, &olen);
if (ret != 0) {
goto exit;
}
if (olen != rest_len) {
goto exit;
}
} else {
ret = mbedtls_gcm_update(&ctx,
ct_test_data[j * 6 + i],
pt_len_test_data[i],
buf, sizeof(buf), &olen);
if (ret != 0) {
goto exit;
}
if (olen != pt_len_test_data[i]) {
goto exit;
}
}
ret = mbedtls_gcm_finish(&ctx, NULL, 0, &olen, tag_buf, 16);
if (ret != 0) {
goto exit;
}
if (memcmp(buf, pt_test_data[pt_index_test_data[i]],
pt_len_test_data[i]) != 0 ||
memcmp(tag_buf, tag_test_data[j * 6 + i], 16) != 0) {
ret = 1;
goto exit;
}
mbedtls_gcm_free(&ctx);
if (verbose != 0) {
mbedtls_printf("passed\n");
}
}
}
if (verbose != 0) {
mbedtls_printf("\n");
}
ret = 0;
exit:
if (ret != 0) {
if (verbose != 0) {
mbedtls_printf("failed\n");
}
mbedtls_gcm_free(&ctx);
}
return ret;
}
#endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
#endif /* MBEDTLS_GCM_C */
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