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AES: optimize AES-GCM

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HW acceleration for GCM is now enabled by default

Closes IDF-1443
This commit is contained in:
Marius Vikhammer
2020-03-10 13:53:09 +08:00
parent 37369a8a57
commit 3351376a11
9 changed files with 511 additions and 140 deletions
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453
components/mbedtls/port/esp32s2/aes.c
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@@ -46,11 +46,11 @@
#include "soc/lldesc.h"
#include "esp_heap_caps.h"
#include "sys/param.h"
#include "esp_pm.h"
#include "freertos/FreeRTOS.h"
#include "freertos/semphr.h"
#define AES_BLOCK_BYTES 16
#define IV_WORDS 4
@@ -63,13 +63,6 @@
busy-waiting, 30000 bytes is approx 0.5 ms */
#define AES_DMA_INTR_TRIG_LEN 2000
#define ESP_GET_BE32(a) __builtin_bswap32( *(uint32_t*)(a) )
#define ESP_PUT_BE32(a, val) \
do { \
*(uint32_t*)(a) = __builtin_bswap32( (uint32_t)(val) ); \
} while (0)
#define ESP_PUT_BE64(a, val) \
do { \
*(uint64_t*)(a) = __builtin_bswap64( (uint64_t)(val) ); \
@@ -90,10 +83,16 @@ typedef enum {
#if defined(CONFIG_MBEDTLS_AES_USE_INTERRUPT)
static SemaphoreHandle_t op_complete_sem;
#if defined(CONFIG_PM_ENABLE)
static esp_pm_lock_handle_t s_pm_cpu_lock;
static esp_pm_lock_handle_t s_pm_sleep_lock;
#endif
#endif
_lock_t crypto_dma_lock;
static _lock_t aes_lock;
static _lock_t s_aes_lock;
static const char *TAG = "esp-aes";
@@ -102,10 +101,11 @@ static inline bool valid_key_length(const esp_aes_context *ctx)
return ctx->key_bytes == 128 / 8 || ctx->key_bytes == 192 / 8 || ctx->key_bytes == 256 / 8;
}
void esp_aes_acquire_hardware( void )
{
/* Need to lock DMA since it is shared with SHA block */
_lock_acquire(&aes_lock);
_lock_acquire(&s_aes_lock);
_lock_acquire(&crypto_dma_lock);
/* Enable AES hardware */
@@ -119,7 +119,7 @@ void esp_aes_release_hardware( void )
periph_module_disable(PERIPH_AES_DMA_MODULE);
_lock_release(&crypto_dma_lock);
_lock_release(&aes_lock);
_lock_release(&s_aes_lock);
}
@@ -234,14 +234,38 @@ static IRAM_ATTR void esp_aes_complete_isr(void *arg)
}
}
static void esp_aes_isr_initialise( void )
static esp_err_t esp_aes_isr_initialise( void )
{
REG_WRITE(AES_INT_CLR_REG, 1);
REG_WRITE(AES_INT_ENA_REG, 1);
if (op_complete_sem == NULL) {
op_complete_sem = xSemaphoreCreateBinary();
if (op_complete_sem == NULL) {
ESP_LOGE(TAG, "Failed to create intr semaphore");
return ESP_FAIL;
}
esp_intr_alloc(ETS_AES_INTR_SOURCE, 0, esp_aes_complete_isr, NULL, NULL);
}
/* AES is clocked proportionally to CPU clock, take power management lock */
#ifdef CONFIG_PM_ENABLE
if (s_pm_cpu_lock == NULL) {
if (esp_pm_lock_create(ESP_PM_NO_LIGHT_SLEEP, 0, "aes_sleep", &s_pm_sleep_lock) != ESP_OK) {
ESP_LOGE(TAG, "Failed to create PM sleep lock");
return ESP_FAIL;
}
if (esp_pm_lock_create(ESP_PM_CPU_FREQ_MAX, 0, "aes_cpu", &s_pm_cpu_lock) != ESP_OK) {
ESP_LOGE(TAG, "Failed to create PM CPU lock");
return ESP_FAIL;
}
}
esp_pm_lock_acquire(s_pm_cpu_lock);
esp_pm_lock_acquire(s_pm_sleep_lock);
#endif
return ESP_OK;
}
#endif // CONFIG_MBEDTLS_AES_USE_INTERRUPT
@@ -257,6 +281,10 @@ static void esp_aes_dma_wait_complete(bool use_intr, lldesc_t *output_desc)
ESP_LOGE("AES", "Timed out waiting for completion of AES Interrupt");
abort();
}
#ifdef CONFIG_PM_ENABLE
esp_pm_lock_release(s_pm_cpu_lock);
esp_pm_lock_release(s_pm_sleep_lock);
#endif // CONFIG_PM_ENABLE
}
#endif
@@ -312,6 +340,7 @@ static int esp_aes_process_dma(esp_aes_context *ctx, const unsigned char *input,
static int esp_aes_process_dma_ext_ram(esp_aes_context *ctx, const unsigned char *input, unsigned char *output, size_t len, uint8_t *stream_out, bool realloc_input, bool realloc_output)
{
size_t chunk_len;
int ret = 0;
int offset = 0;
unsigned char *input_buf = NULL;
unsigned char *output_buf = NULL;
@@ -324,7 +353,8 @@ static int esp_aes_process_dma_ext_ram(esp_aes_context *ctx, const unsigned char
if (input_buf == NULL) {
ESP_LOGE(TAG, "Failed to allocate memory");
return -1;
ret = -1;
goto cleanup;
}
}
@@ -333,7 +363,8 @@ static int esp_aes_process_dma_ext_ram(esp_aes_context *ctx, const unsigned char
if (output_buf == NULL) {
ESP_LOGE(TAG, "Failed to allocate memory");
return -1;
ret = -1;
goto cleanup;
}
} else {
output_buf = output;
@@ -351,7 +382,8 @@ static int esp_aes_process_dma_ext_ram(esp_aes_context *ctx, const unsigned char
}
if (esp_aes_process_dma(ctx, dma_input, output_buf, chunk_len, stream_out) != 0) {
return -1;
ret = -1;
goto cleanup;
}
if (realloc_output) {
@@ -364,6 +396,8 @@ static int esp_aes_process_dma_ext_ram(esp_aes_context *ctx, const unsigned char
offset += chunk_len;
}
cleanup:
if (realloc_input) {
free(input_buf);
}
@@ -371,7 +405,7 @@ static int esp_aes_process_dma_ext_ram(esp_aes_context *ctx, const unsigned char
free(output_buf);
}
return 0;
return ret;
}
/* Encrypt/decrypt the input using DMA */
@@ -474,7 +508,10 @@ static int esp_aes_process_dma(esp_aes_context *ctx, const unsigned char *input,
/* Only use interrupt for long AES operations */
if (len > AES_DMA_INTR_TRIG_LEN) {
use_intr = true;
esp_aes_isr_initialise();
if (esp_aes_isr_initialise() == ESP_FAIL) {
ret = -1;
goto cleanup;
}
} else
#endif
{
@@ -483,10 +520,10 @@ static int esp_aes_process_dma(esp_aes_context *ctx, const unsigned char *input,
/* Start AES operation */
REG_WRITE(AES_TRIGGER_REG, 1);
esp_aes_dma_wait_complete(use_intr, out_desc_head);
#if (CONFIG_SPIRAM_USE_CAPS_ALLOC || CONFIG_SPIRAM_USE_MALLOC)
if (block_bytes > 0) {
if (esp_ptr_external_ram(output)) {
@@ -510,6 +547,25 @@ cleanup:
}
static int esp_aes_validate_input(esp_aes_context *ctx, const unsigned char *input,
unsigned char *output )
{
if (!ctx) {
ESP_LOGE(TAG, "No AES context supplied");
return -1;
}
if (!input) {
ESP_LOGE(TAG, "No input supplied");
return -1;
}
if (!output) {
ESP_LOGE(TAG, "No output supplied");
return -1;
}
return 0;
}
/*
* AES-ECB single block encryption
@@ -520,6 +576,10 @@ int esp_internal_aes_encrypt( esp_aes_context *ctx,
{
int r;
if (esp_aes_validate_input(ctx, input, output)) {
return -1;
}
if (!valid_key_length(ctx)) {
return MBEDTLS_ERR_AES_INVALID_KEY_LENGTH;
}
@@ -550,6 +610,10 @@ int esp_internal_aes_decrypt( esp_aes_context *ctx,
{
int r;
if (esp_aes_validate_input(ctx, input, output)) {
return -1;
}
if (!valid_key_length(ctx)) {
return MBEDTLS_ERR_AES_INVALID_KEY_LENGTH;
}
@@ -582,6 +646,10 @@ int esp_aes_crypt_ecb( esp_aes_context *ctx,
{
int r;
if (esp_aes_validate_input(ctx, input, output)) {
return -1;
}
if (!valid_key_length(ctx)) {
return MBEDTLS_ERR_AES_INVALID_KEY_LENGTH;
}
@@ -607,11 +675,19 @@ int esp_aes_crypt_cbc( esp_aes_context *ctx,
unsigned char *output )
{
int r = 0;
if (esp_aes_validate_input(ctx, input, output)) {
return -1;
}
if (!iv) {
ESP_LOGE(TAG, "No IV supplied");
return -1;
}
/* For CBC input length should be multiple of
* AES BLOCK BYTES
* */
if ( length % AES_BLOCK_BYTES ) {
if ( (length % AES_BLOCK_BYTES) || (length == 0) ) {
return ERR_ESP_AES_INVALID_INPUT_LENGTH;
}
@@ -652,6 +728,16 @@ int esp_aes_crypt_cfb8( esp_aes_context *ctx,
int r = 0;
size_t block_bytes = length - (length % AES_BLOCK_BYTES);
if (esp_aes_validate_input(ctx, input, output)) {
return -1;
}
if (!iv) {
ESP_LOGE(TAG, "No IV supplied");
return -1;
}
if (!valid_key_length(ctx)) {
return MBEDTLS_ERR_AES_INVALID_KEY_LENGTH;
}
@@ -728,12 +814,28 @@ int esp_aes_crypt_cfb128( esp_aes_context *ctx,
uint8_t c;
int r = 0;
size_t stream_bytes = 0;
size_t n = *iv_off;
size_t n;
if (esp_aes_validate_input(ctx, input, output)) {
return -1;
}
if (!iv) {
ESP_LOGE(TAG, "No IV supplied");
return -1;
}
if (!iv_off) {
ESP_LOGE(TAG, "No IV offset supplied");
return -1;
}
if (!valid_key_length(ctx)) {
return MBEDTLS_ERR_AES_INVALID_KEY_LENGTH;
}
n = *iv_off;
/* First process the *iv_off bytes
* which are pending from the previous call to this API
*/
@@ -796,8 +898,25 @@ int esp_aes_crypt_ofb( esp_aes_context *ctx,
unsigned char *output )
{
int r = 0;
size_t n = *iv_off;
size_t n;
size_t stream_bytes = 0;
if (esp_aes_validate_input(ctx, input, output)) {
return -1;
}
if (!iv) {
ESP_LOGE(TAG, "No IV supplied");
return -1;
}
if (!iv_off) {
ESP_LOGE(TAG, "No IV offset supplied");
return -1;
}
n = *iv_off;
/* If there is an offset then use the output of the previous AES block
(the updated IV) to calculate the new output */
while (n > 0 && length > 0) {
@@ -841,7 +960,23 @@ int esp_aes_crypt_ctr( esp_aes_context *ctx,
unsigned char *output )
{
int r = 0;
size_t n = *nc_off;
size_t n;
if (esp_aes_validate_input(ctx, input, output)) {
return -1;
}
if (!nonce_counter) {
ESP_LOGE(TAG, "No nonce supplied");
return -1;
}
if (!nc_off) {
ESP_LOGE(TAG, "No nonce offset supplied");
return -1;
}
n = *nc_off;
if (!valid_key_length(ctx)) {
return MBEDTLS_ERR_AES_INVALID_KEY_LENGTH;
@@ -881,7 +1016,7 @@ int esp_aes_crypt_ctr( esp_aes_context *ctx,
return r;
}
static void esp_gcm_ghash(uint8_t *h0, const unsigned char *x, size_t x_len, uint8_t *j0);
static void esp_gcm_ghash(esp_gcm_context *ctx, const unsigned char *x, size_t x_len, uint8_t *z);
/*
* Calculates the Initial Counter Block, J0
@@ -899,14 +1034,16 @@ static void esp_gcm_derive_J0(esp_gcm_context *ctx)
memcpy(ctx->J0, ctx->iv, ctx->iv_len);
ctx->J0[AES_BLOCK_BYTES - 1] |= 1;
} else {
/* For IV != 96 bit, J0 = GHASH(IV || 0[s+64] || [len(IV)]64) */
/* For IV != 96 bit, J0 = GHASH(IV || 0[s+64] || [len(IV)]64) */
/* First calculate GHASH on IV */
esp_gcm_ghash(ctx->H, ctx->iv, ctx->iv_len, ctx->J0);
esp_gcm_ghash(ctx, ctx->iv, ctx->iv_len, ctx->J0);
/* Next create 128 bit block which is equal to
64 bit 0 + iv length truncated to 64 bits */
ESP_PUT_BE64(len_buf + 8, ctx->iv_len * 8);
/* Calculate GHASH on last block */
esp_gcm_ghash(ctx->H, len_buf, 16, ctx->J0);
esp_gcm_ghash(ctx, len_buf, 16, ctx->J0);
}
}
@@ -942,68 +1079,146 @@ static void xor_data(uint8_t *d, const uint8_t *s)
*dst++ ^= *src++;
}
/* Right shift 128 bits by 1 in Big Endian format */
static void right_shift_be(uint8_t *v)
{
uint8_t prev_lsb = 0, cur_lsb;
uint32_t data;
for (int i = 0; i < 16; i += 4) {
data = ESP_GET_BE32(v + i);
cur_lsb = v[i + 3] & 0x1;
data = (data >> 1) | (prev_lsb << 31);
ESP_PUT_BE32((v + i), data);
prev_lsb = cur_lsb;
}
}
/* Multiplication in GF(2^128)
* z = x * y
*
* Steps:
* 1. Let x0.x1...x127 denote the sequence of bits in X.
* 2. Let Z0 =[0]128 and V0 = Y.
* 3. For i = 0 to 127, calculate blocks Zi+1 and Vi+1 as follows:
*
* Zi+1 = Zi if [x]i = 0, else Zi+1 = Zi ^ Vi
* Vi+1 = Vi >> 1 if LSB(Vi) = 0, else Vi+1 = (Vi >> 1) ^ R
*
* Note: as per AES-GCM spec 800-38D for Vi+1 calculation LSB(Vi)
* should be check for 1 but this is actually big endian format so
* we need to check MSB(V[15])
/*
* 32-bit integer manipulation macros (big endian)
*/
static void gcm_mult(const uint8_t *x, const uint8_t *y, uint8_t *z)
#ifndef GET_UINT32_BE
#define GET_UINT32_BE(n,b,i) \
{ \
(n) = ( (uint32_t) (b)[(i) ] << 24 ) \
| ( (uint32_t) (b)[(i) + 1] << 16 ) \
| ( (uint32_t) (b)[(i) + 2] << 8 ) \
| ( (uint32_t) (b)[(i) + 3] ); \
}
#endif
#ifndef PUT_UINT32_BE
#define PUT_UINT32_BE(n,b,i) \
{ \
(b)[(i) ] = (unsigned char) ( (n) >> 24 ); \
(b)[(i) + 1] = (unsigned char) ( (n) >> 16 ); \
(b)[(i) + 2] = (unsigned char) ( (n) >> 8 ); \
(b)[(i) + 3] = (unsigned char) ( (n) ); \
}
#endif
/* Based on MbedTLS's implemenation
*
* 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( esp_gcm_context *ctx )
{
uint8_t v[16];
int i, j;
uint32_t R = 0x000000E1; /* Field polynomial in Big endian format */
uint64_t hi, lo;
uint64_t vl, vh;
unsigned char *h;
memset(z, 0, 16); /* Z_0 = 0^128 */
memcpy(v, y, 16); /* V_0 = Y */
h = ctx->H;
for (i = 0; i < 16; i++) {
/* Test each bit in a byte of x[i]
* Again as per spec we need to test each bit
* in x from index 0 to 127, however its big
* endian format for each sub byte
*/
for (j = 0; j < 8; j++) {
if (x[i] & (1 << (7 - j))) {
xor_data(z, v);
}
/* https://pdfs.semanticscholar.org/1246/a9ad98dc0421ccfc945e6529c886f23e848d.pdf
* page 9
*/
if (v[15] & 0x1) {
right_shift_be(v);
v[0] ^= R;
} else {
right_shift_be(v);
}
/* pack h as two 64-bits ints, big-endian */
GET_UINT32_BE( hi, h, 0 );
GET_UINT32_BE( lo, h, 4 );
vh = (uint64_t) hi << 32 | lo;
GET_UINT32_BE( hi, h, 8 );
GET_UINT32_BE( lo, 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;
/* 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 );
}
/*
* 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 uint64_t last4[16] =
{
0x0000, 0x1c20, 0x3840, 0x2460,
0x7080, 0x6ca0, 0x48c0, 0x54e0,
0xe100, 0xfd20, 0xd940, 0xc560,
0x9180, 0x8da0, 0xa9c0, 0xb5e0
};
/* Based on MbedTLS's implemenation
*
* 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( esp_gcm_context *ctx, const unsigned char x[16],
unsigned char output[16] )
{
int i = 0;
unsigned char lo, hi, rem;
uint64_t zh, zl;
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;
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];
}
PUT_UINT32_BE( zh >> 32, output, 0 );
PUT_UINT32_BE( zh, output, 4 );
PUT_UINT32_BE( zl >> 32, output, 8 );
PUT_UINT32_BE( zl, output, 12 );
}
@@ -1024,14 +1239,16 @@ int esp_aes_gcm_setkey( esp_gcm_context *ctx,
return ( 0 );
}
/* AES-GCM GHASH calculation j0 = GHASH(x) using h0 hash key
/* AES-GCM GHASH calculation z = GHASH(x) using h0 hash key
*/
static void esp_gcm_ghash(uint8_t *h0, const unsigned char *x, size_t x_len, uint8_t *j0)
static void esp_gcm_ghash(esp_gcm_context *ctx, const unsigned char *x, size_t x_len, uint8_t *z)
{
uint8_t y0[AES_BLOCK_BYTES], tmp[AES_BLOCK_BYTES];
uint8_t tmp[AES_BLOCK_BYTES];
memset(tmp, 0, AES_BLOCK_BYTES);
/* GHASH(X) is calculated on input string which is multiple of 128 bits
* If input string bit length is not multiple of 128 bits it needs to
* be padded by 0
@@ -1046,12 +1263,12 @@ static void esp_gcm_ghash(uint8_t *h0, const unsigned char *x, size_t x_len, uin
/* If input bit string is >= 128 bits, process full 128 bit blocks */
while (x_len >= AES_BLOCK_BYTES) {
xor_data(j0, x);
gcm_mult(j0, h0, y0);
xor_data(z, x);
gcm_mult(ctx, z, z);
x += AES_BLOCK_BYTES;
x_len -= AES_BLOCK_BYTES;
memcpy(j0, y0, AES_BLOCK_BYTES);
}
/* If input bit string is not multiple of 128 create last 128 bit
@@ -1059,14 +1276,12 @@ static void esp_gcm_ghash(uint8_t *h0, const unsigned char *x, size_t x_len, uin
*/
if (x_len) {
memcpy(tmp, x, x_len);
xor_data(j0, tmp);
gcm_mult(j0, h0, y0);
memcpy(j0, y0, AES_BLOCK_BYTES);
xor_data(z, tmp);
gcm_mult(ctx, z, z);
}
}
/* Function to init AES GCM context to zero */
void esp_aes_gcm_init( esp_gcm_context *ctx)
{
@@ -1103,6 +1318,22 @@ int esp_aes_gcm_starts( esp_gcm_context *ctx,
return ( MBEDTLS_ERR_GCM_BAD_INPUT );
}
if (!ctx) {
ESP_LOGE(TAG, "No AES context supplied");
return -1;
}
if (!iv) {
ESP_LOGE(TAG, "No IV supplied");
return -1;
}
if ( (aad_len > 0) && !aad) {
ESP_LOGE(TAG, "No aad supplied");
return -1;
}
/* Initialize AES-GCM context */
ctx->iv = iv;
ctx->iv_len = iv_len;
@@ -1123,6 +1354,7 @@ int esp_aes_gcm_starts( esp_gcm_context *ctx,
memcpy(ctx->H, (uint8_t *)AES_H_BASE, AES_BLOCK_BYTES);
esp_aes_release_hardware();
gcm_gen_table(ctx);
/* Once H is obtained we need to derive J0 (Initial Counter Block) */
esp_gcm_derive_J0(ctx);
@@ -1133,6 +1365,9 @@ int esp_aes_gcm_starts( esp_gcm_context *ctx,
*/
memcpy(ctx->ori_j0, ctx->J0, 16);
esp_gcm_ghash(ctx, ctx->aad, ctx->aad_len, ctx->ghash);
return ( 0 );
}
@@ -1143,9 +1378,21 @@ int esp_aes_gcm_update( esp_gcm_context *ctx,
unsigned char *output )
{
size_t nc_off = 0;
uint8_t stream[AES_BLOCK_BYTES] = {0};
uint8_t nonce_counter[AES_BLOCK_BYTES] = {0};
uint8_t gcm_s[AES_BLOCK_BYTES] = {0};
uint8_t stream[AES_BLOCK_BYTES] = {0};
if (!ctx) {
ESP_LOGE(TAG, "No GCM context supplied");
return -1;
}
if (!input) {
ESP_LOGE(TAG, "No input supplied");
return -1;
}
if (!output) {
ESP_LOGE(TAG, "No output supplied");
return -1;
}
if ( output > input && (size_t) ( output - input ) < length ) {
return ( MBEDTLS_ERR_GCM_BAD_INPUT );
@@ -1154,17 +1401,12 @@ int esp_aes_gcm_update( esp_gcm_context *ctx,
* calculate GHASH on aad and preincrement the ICB
*/
if (ctx->gcm_state == ESP_AES_GCM_STATE_INIT) {
/* The GHASH calculation is done at multiple stages
* Here we calculate GHASH of AAD and save it
*/
esp_gcm_ghash(ctx->H, ctx->aad, ctx->aad_len, gcm_s);
/* Jo needs to be incremented first time, later the GCTR
/* Jo needs to be incremented first time, later the CTR
* operation will auto update it
*/
increment32_j0(ctx, nonce_counter);
ctx->gcm_state = ESP_AES_GCM_STATE_UPDATE;
} else if (ctx->gcm_state == ESP_AES_GCM_STATE_UPDATE) {
memcpy(gcm_s, ctx->S, AES_BLOCK_BYTES);
memcpy(nonce_counter, ctx->J0, AES_BLOCK_BYTES);
}
@@ -1178,12 +1420,11 @@ int esp_aes_gcm_update( esp_gcm_context *ctx,
/* Perform intermediate GHASH on "encrypted" data irrespective of mode */
if (ctx->mode == ESP_AES_DECRYPT) {
esp_gcm_ghash(ctx->H, input, length, gcm_s);
esp_gcm_ghash(ctx, input, length, ctx->ghash);
} else {
esp_gcm_ghash(ctx->H, output, length, gcm_s);
}
esp_gcm_ghash(ctx, output, length, ctx->ghash);
memcpy(ctx->S, gcm_s, AES_BLOCK_BYTES);
}
return 0;
}
@@ -1203,10 +1444,10 @@ int esp_aes_gcm_finish( esp_gcm_context *ctx,
/* Calculate final GHASH on aad_len, data length */
ESP_PUT_BE64(len_block, ctx->aad_len * 8);
ESP_PUT_BE64(len_block + 8, ctx->data_len * 8);
esp_gcm_ghash(ctx->H, len_block, AES_BLOCK_BYTES, ctx->S);
esp_gcm_ghash(ctx, len_block, AES_BLOCK_BYTES, ctx->ghash);
/* Tag T = GCTR(J0, S) where T is truncated to tag_len */
esp_aes_crypt_ctr(&ctx->aes_ctx, tag_len, &nc_off, ctx->ori_j0, 0, ctx->S, tag);
/* Tag T = GCTR(J0, ) where T is truncated to tag_len */
esp_aes_crypt_ctr(&ctx->aes_ctx, tag_len, &nc_off, ctx->ori_j0, 0, ctx->ghash, tag);
return 0;
}