[sw/sca] Switch AES to use dif_aes
Switch to SCA simple serial to use AES DIF.
Signed-off-by: Miguel Osorio <miguelosorio@google.com>
diff --git a/sw/device/sca/aes_serial.c b/sw/device/sca/aes_serial.c
index 7923cda..372421e 100644
--- a/sw/device/sca/aes_serial.c
+++ b/sw/device/sca/aes_serial.c
@@ -2,13 +2,15 @@
// Licensed under the Apache License, Version 2.0, see LICENSE for details.
// SPDX-License-Identifier: Apache-2.0
-#include "sw/device/lib/aes.h"
#include "sw/device/lib/base/memory.h"
+#include "sw/device/lib/dif/dif_aes.h"
#include "sw/device/lib/runtime/log.h"
#include "sw/device/sca/lib/prng.h"
#include "sw/device/sca/lib/sca.h"
#include "sw/device/sca/lib/simple_serial.h"
+#include "hw/top_earlgrey/sw/autogen/top_earlgrey.h"
+
/**
* OpenTitan program for AES side-channel analysis.
*
@@ -37,7 +39,7 @@
kIbexAesSleepCycles = 400,
};
-static aes_cfg_t aes_cfg;
+static dif_aes_t aes;
/**
* Simple serial 'k' (set key) command handler.
@@ -51,7 +53,23 @@
*/
static void aes_serial_set_key(const uint8_t *key, size_t key_len) {
SS_CHECK(key_len == kAesKeyLength);
- aes_key_put(key, /*key_share1=*/(uint8_t[kAesKeyLength]){0}, aes_cfg.key_len);
+ dif_aes_transaction_t transaction = {
+ .key_len = kDifAesKey128,
+ .masking = kDifAesMaskingInternalPrng,
+ .mode = kDifAesModeEncrypt,
+ .operation = kDifAesOperationManual,
+ };
+ dif_aes_key_share_t key_shares;
+ memcpy(key_shares.share0, key, sizeof(key_shares.share0));
+ memset(key_shares.share1, 0, sizeof(key_shares.share1));
+ SS_CHECK(dif_aes_start_ecb(&aes, &transaction, key_shares) == kDifAesOk);
+}
+
+/**
+ * Callback wrapper for AES manual trigger function.
+ */
+static void aes_manual_trigger(void) {
+ SS_CHECK(dif_aes_trigger(&aes, kDifAesTriggerStart) == kDifAesOk);
}
/**
@@ -66,7 +84,15 @@
* @return Result of the operation.
*/
static void aes_serial_encrypt(const uint8_t *plaintext, size_t plaintext_len) {
- aes_data_put_wait(plaintext);
+ bool ready = false;
+ do {
+ SS_CHECK(dif_aes_get_status(&aes, kDifAesStatusInputReady, &ready) ==
+ kDifAesOk);
+ } while (!ready);
+ dif_aes_data_t data;
+ SS_CHECK(plaintext_len <= sizeof(data.data));
+ memcpy(data.data, plaintext, plaintext_len);
+ SS_CHECK(dif_aes_load_data(&aes, data) == kDifAesOk);
// Start AES operation (this triggers the capture) and go to sleep.
// Using the SecAesStartTriggerDelay hardware parameter, the AES unit is
@@ -93,9 +119,16 @@
aes_serial_encrypt(plaintext, plaintext_len);
sca_set_trigger_low();
- uint8_t ciphertext[kAesTextLength] = {0};
- aes_data_get_wait(ciphertext);
- simple_serial_send_packet('r', ciphertext, ARRAYSIZE(ciphertext));
+ bool ready = false;
+ do {
+ SS_CHECK(dif_aes_get_status(&aes, kDifAesStatusOutputValid, &ready) ==
+ kDifAesOk);
+ } while (!ready);
+
+ dif_aes_data_t ciphertext;
+ SS_CHECK(dif_aes_read_output(&aes, &ciphertext) == kDifAesOk);
+ simple_serial_send_packet('r', (uint8_t *)ciphertext.data,
+ sizeof(ciphertext.data));
}
/**
@@ -135,24 +168,27 @@
}
sca_set_trigger_low();
- uint8_t ciphertext[kAesTextLength] = {0};
- aes_data_get_wait(ciphertext);
- simple_serial_send_packet('r', ciphertext, ARRAYSIZE(ciphertext));
+ bool ready = false;
+ do {
+ SS_CHECK(dif_aes_get_status(&aes, kDifAesStatusOutputValid, &ready) ==
+ kDifAesOk);
+ } while (!ready);
+
+ dif_aes_data_t ciphertext;
+ SS_CHECK(dif_aes_read_output(&aes, &ciphertext) == kDifAesOk);
+ simple_serial_send_packet('r', (uint8_t *)ciphertext.data,
+ sizeof(ciphertext.data));
}
/**
* Initializes the AES peripheral.
*/
static void init_aes(void) {
- aes_cfg.key_len = kAes128;
- aes_cfg.operation = kAesEnc;
- aes_cfg.mode = kAesEcb;
- aes_cfg.manual_operation = true;
- aes_clear();
- while (!aes_idle()) {
- ;
- }
- aes_init(aes_cfg);
+ dif_aes_params_t params = {
+ .base_addr = mmio_region_from_addr(TOP_EARLGREY_AES_BASE_ADDR),
+ };
+ SS_CHECK(dif_aes_init(params, &aes) == kDifAesOk);
+ SS_CHECK(dif_aes_reset(&aes) == kDifAesOk);
}
/**
diff --git a/sw/device/sca/meson.build b/sw/device/sca/meson.build
index f3bdd93..13f31c2 100644
--- a/sw/device/sca/meson.build
+++ b/sw/device/sca/meson.build
@@ -12,7 +12,7 @@
dependencies: [
device_lib,
riscv_crt,
- sw_lib_aes,
+ sw_lib_dif_aes,
sw_lib_mmio,
sw_lib_runtime_hart,
sw_lib_runtime_log,
