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-rw-r--r--plat/st/common/stm32mp_crypto_lib.c661
1 files changed, 661 insertions, 0 deletions
diff --git a/plat/st/common/stm32mp_crypto_lib.c b/plat/st/common/stm32mp_crypto_lib.c
new file mode 100644
index 0000000..d644242
--- /dev/null
+++ b/plat/st/common/stm32mp_crypto_lib.c
@@ -0,0 +1,661 @@
+/*
+ * Copyright (c) 2022, STMicroelectronics - All Rights Reserved
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <endian.h>
+#include <errno.h>
+
+#include <common/debug.h>
+#include <drivers/auth/crypto_mod.h>
+#include <drivers/io/io_storage.h>
+#include <drivers/st/bsec.h>
+#include <drivers/st/stm32_hash.h>
+#include <drivers/st/stm32_pka.h>
+#include <drivers/st/stm32_rng.h>
+#include <drivers/st/stm32_saes.h>
+#include <lib/xlat_tables/xlat_tables_v2.h>
+#include <mbedtls/asn1.h>
+#include <mbedtls/md.h>
+#include <mbedtls/oid.h>
+#include <mbedtls/platform.h>
+#include <mbedtls/x509.h>
+#include <plat/common/platform.h>
+#include <tools_share/firmware_encrypted.h>
+
+#include <platform_def.h>
+
+#define CRYPTO_HASH_MAX_SIZE 32U
+#define CRYPTO_SIGN_MAX_SIZE 64U
+#define CRYPTO_PUBKEY_MAX_SIZE 64U
+#define CRYPTO_MAX_TAG_SIZE 16U
+
+/* brainpoolP256t1 OID is not defined in mbedTLS */
+#define OID_EC_GRP_BP256T1 MBEDTLS_OID_EC_BRAINPOOL_V1 "\x08"
+
+#if STM32MP_CRYPTO_ROM_LIB
+struct stm32mp_auth_ops {
+ uint32_t (*verify_signature)(uint8_t *hash_in, uint8_t *pubkey_in,
+ uint8_t *signature, uint32_t ecc_algo);
+};
+
+static struct stm32mp_auth_ops auth_ops;
+#endif
+
+static void crypto_lib_init(void)
+{
+ boot_api_context_t *boot_context __maybe_unused;
+ int ret;
+
+ NOTICE("TRUSTED_BOARD_BOOT support enabled\n");
+
+ ret = stm32_hash_register();
+ if (ret != 0) {
+ ERROR("HASH init (%d)\n", ret);
+ panic();
+ }
+
+ if (stm32mp_is_closed_device() || stm32mp_is_auth_supported()) {
+#if STM32MP_CRYPTO_ROM_LIB
+ boot_context = (boot_api_context_t *)stm32mp_get_boot_ctx_address();
+ auth_ops.verify_signature = boot_context->bootrom_ecdsa_verify_signature;
+#else
+ /* Use hardware peripherals */
+ if (stm32_rng_init() != 0) {
+ panic();
+ }
+
+ if (stm32_saes_driver_init() != 0) {
+ panic();
+ }
+
+ if (stm32_pka_init() != 0) {
+ panic();
+ }
+#endif
+ }
+}
+
+int get_plain_pk_from_asn1(void *pk_ptr, unsigned int pk_len, void **plain_pk,
+ unsigned int *len, int *pk_alg)
+{
+ int ret;
+ mbedtls_pk_context mbedtls_pk = {0};
+ unsigned char *p, *end;
+ mbedtls_asn1_buf alg_params = {0};
+ mbedtls_asn1_buf alg_oid = {0};
+
+ *plain_pk = NULL;
+ *len = 0U;
+
+ /* Parse the public key */
+ mbedtls_pk_init(&mbedtls_pk);
+ p = (unsigned char *)pk_ptr;
+ end = (unsigned char *)(p + pk_len);
+
+ ret = mbedtls_asn1_get_tag(&p, end, len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
+ if (ret != 0) {
+ return -EINVAL;
+ }
+
+ end = p + *len;
+ ret = mbedtls_asn1_get_alg(&p, end, &alg_oid, &alg_params);
+ if (ret != 0) {
+ VERBOSE("%s: mbedtls_asn1_get_alg (%d)\n", __func__, ret);
+ return -EINVAL;
+ }
+
+ if (pk_alg != NULL) {
+ if ((strlen(MBEDTLS_OID_EC_GRP_SECP256R1) == alg_params.len) &&
+ (memcmp(MBEDTLS_OID_EC_GRP_SECP256R1, alg_params.p, alg_params.len) == 0)) {
+ *pk_alg = BOOT_API_ECDSA_ALGO_TYPE_P256NIST;
+ } else if ((strlen(OID_EC_GRP_BP256T1) == alg_params.len) &&
+ (memcmp(OID_EC_GRP_BP256T1, alg_params.p, alg_params.len) == 0)) {
+ *pk_alg = BOOT_API_ECDSA_ALGO_TYPE_BRAINPOOL256;
+ } else {
+ ERROR("%s: Algorithm is not supported\n", __func__);
+ return -EINVAL;
+ }
+ }
+
+ ret = mbedtls_asn1_get_bitstring_null(&p, end, len);
+ if (ret != 0) {
+ VERBOSE("%s: mbedtls_asn1_get_bitstring_null (%d)\n", __func__, ret);
+ return -EINVAL;
+ }
+
+ /* We remove the ident (0x04) first byte. */
+ if ((*len < 1U) || (p[0] != MBEDTLS_ASN1_OCTET_STRING)) {
+ VERBOSE("%s: not expected len or tag\n", __func__);
+ return -EINVAL;
+ }
+
+ *len = *len - 1U;
+ *plain_pk = p + 1U;
+
+ return 0;
+}
+
+#if STM32MP_CRYPTO_ROM_LIB
+uint32_t verify_signature(uint8_t *hash_in, uint8_t *pubkey_in,
+ uint8_t *signature, uint32_t ecc_algo)
+{
+ int ret;
+
+ ret = mmap_add_dynamic_region(STM32MP_ROM_BASE, STM32MP_ROM_BASE,
+ STM32MP_ROM_SIZE_2MB_ALIGNED, MT_CODE | MT_SECURE);
+ if (ret != 0) {
+ VERBOSE("%s: mmap_add_dynamic_region (%d)\n", __func__, ret);
+ return CRYPTO_ERR_SIGNATURE;
+ }
+
+ ret = auth_ops.verify_signature(hash_in, pubkey_in, signature, ecc_algo);
+
+ if (ret != BOOT_API_RETURN_OK) {
+ VERBOSE("%s: auth_ops.verify_sign (%d)\n", __func__, ret);
+ ret = CRYPTO_ERR_SIGNATURE;
+ } else {
+ ret = 0;
+ }
+
+ mmap_remove_dynamic_region(STM32MP_ROM_BASE, STM32MP_ROM_SIZE_2MB_ALIGNED);
+
+ return ret;
+}
+
+int plat_convert_pk(void *full_pk_ptr, unsigned int full_pk_len,
+ void **hashed_pk_ptr, unsigned int *hashed_pk_len)
+{
+ return get_plain_pk_from_asn1(full_pk_ptr, full_pk_len, hashed_pk_ptr, hashed_pk_len, NULL);
+}
+#else /* STM32MP_CRYPTO_ROM_LIB*/
+static uint32_t verify_signature(uint8_t *hash_in, uint8_t *pubkey_in,
+ uint8_t *signature, uint32_t ecc_algo)
+{
+ int ret = -1;
+ enum stm32_pka_ecdsa_curve_id cid;
+
+ switch (ecc_algo) {
+ case BOOT_API_ECDSA_ALGO_TYPE_P256NIST:
+#if PKA_USE_NIST_P256
+ cid = PKA_NIST_P256;
+ ret = 0;
+#else
+ WARN("%s nist_p256 requested but not included\n", __func__);
+#endif
+ break;
+ case BOOT_API_ECDSA_ALGO_TYPE_BRAINPOOL256:
+#if PKA_USE_BRAINPOOL_P256T1
+ cid = PKA_BRAINPOOL_P256T1;
+ ret = 0;
+#else
+ WARN("%s brainpool_p256t1 requested but not included\n", __func__);
+#endif
+ break;
+ default:
+ WARN("%s unexpected ecc_algo(%u)\n", __func__, ecc_algo);
+ break;
+ }
+
+ if (ret < 0) {
+ return CRYPTO_ERR_SIGNATURE;
+ }
+
+ ret = stm32_pka_ecdsa_verif(hash_in,
+ BOOT_API_SHA256_DIGEST_SIZE_IN_BYTES,
+ signature, BOOT_API_ECDSA_SIGNATURE_LEN_IN_BYTES / 2U,
+ signature + BOOT_API_ECDSA_SIGNATURE_LEN_IN_BYTES / 2U,
+ BOOT_API_ECDSA_SIGNATURE_LEN_IN_BYTES / 2U,
+ pubkey_in, BOOT_API_ECDSA_PUB_KEY_LEN_IN_BYTES / 2U,
+ pubkey_in + BOOT_API_ECDSA_PUB_KEY_LEN_IN_BYTES / 2U,
+ BOOT_API_ECDSA_PUB_KEY_LEN_IN_BYTES / 2U, cid);
+ if (ret < 0) {
+ return CRYPTO_ERR_SIGNATURE;
+ }
+
+ return 0;
+}
+
+int plat_convert_pk(void *full_pk_ptr, unsigned int full_pk_len,
+ void **hashed_pk_ptr, unsigned int *hashed_pk_len)
+{
+ static uint8_t st_pk[CRYPTO_PUBKEY_MAX_SIZE + sizeof(uint32_t)];
+ int ret;
+ void *plain_pk;
+ unsigned int len;
+ int curve_id;
+ uint32_t cid;
+
+ ret = get_plain_pk_from_asn1(full_pk_ptr, full_pk_len, &plain_pk, &len, &curve_id);
+ if ((ret != 0) || (len > CRYPTO_PUBKEY_MAX_SIZE)) {
+ return -EINVAL;
+ }
+
+ cid = curve_id; /* we want value of curve_id (1 or 2) in a uint32_t */
+
+ memcpy(st_pk, &cid, sizeof(cid));
+ memcpy(st_pk + sizeof(cid), plain_pk, len);
+
+ *hashed_pk_ptr = st_pk;
+ *hashed_pk_len = len + sizeof(cid);
+
+ return 0;
+}
+#endif /* STM32MP_CRYPTO_ROM_LIB */
+
+static int get_plain_digest_from_asn1(void *digest_ptr, unsigned int digest_len,
+ uint8_t **out, size_t *out_len, mbedtls_md_type_t *md_alg)
+{
+ int ret;
+ mbedtls_asn1_buf hash_oid, params;
+ size_t len;
+ unsigned char *p, *end;
+
+ *out = NULL;
+ *out_len = 0U;
+
+ /* Digest info should be an MBEDTLS_ASN1_SEQUENCE */
+ p = (unsigned char *)digest_ptr;
+ end = p + digest_len;
+ ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED |
+ MBEDTLS_ASN1_SEQUENCE);
+ if (ret != 0) {
+ return ret;
+ }
+
+ /* Get the hash algorithm */
+ ret = mbedtls_asn1_get_alg(&p, end, &hash_oid, &params);
+ if (ret != 0) {
+ return ret;
+ }
+
+ ret = mbedtls_oid_get_md_alg(&hash_oid, md_alg);
+ if (ret != 0) {
+ return ret;
+ }
+
+ ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING);
+ if (ret != 0) {
+ return ret;
+ }
+
+ /* Length of hash must match the algorithm's size */
+ if (len != BOOT_API_SHA256_DIGEST_SIZE_IN_BYTES) {
+ return -1;
+ }
+
+ *out = p;
+ *out_len = len;
+
+ return 0;
+}
+
+static int crypto_verify_signature(void *data_ptr, unsigned int data_len,
+ void *sig_ptr, unsigned int sig_len,
+ void *sig_alg, unsigned int sig_alg_len,
+ void *pk_ptr, unsigned int pk_len)
+{
+ uint8_t image_hash[CRYPTO_HASH_MAX_SIZE] = {0};
+ uint8_t sig[CRYPTO_SIGN_MAX_SIZE];
+ uint8_t my_pk[CRYPTO_PUBKEY_MAX_SIZE];
+ int ret;
+ size_t len;
+ mbedtls_asn1_sequence seq;
+ mbedtls_asn1_sequence *cur;
+ unsigned char *p, *end;
+ int curve_id;
+ mbedtls_asn1_buf sig_oid, sig_params;
+ mbedtls_md_type_t md_alg;
+ mbedtls_pk_type_t pk_alg;
+ size_t bignum_len = sizeof(sig) / 2U;
+ unsigned int seq_num = 0U;
+
+ if (!stm32mp_is_closed_device() && !stm32mp_is_auth_supported()) {
+ return CRYPTO_SUCCESS;
+ }
+
+ /* Get pointers to signature OID and parameters */
+ p = (unsigned char *)sig_alg;
+ end = (unsigned char *)(p + sig_alg_len);
+ ret = mbedtls_asn1_get_alg(&p, end, &sig_oid, &sig_params);
+ if (ret != 0) {
+ VERBOSE("%s: mbedtls_asn1_get_alg (%d)\n", __func__, ret);
+ return CRYPTO_ERR_SIGNATURE;
+ }
+
+ /* Get the actual signature algorithm (MD + PK) */
+ ret = mbedtls_oid_get_sig_alg(&sig_oid, &md_alg, &pk_alg);
+ if (ret != 0) {
+ VERBOSE("%s: mbedtls_oid_get_sig_alg (%d)\n", __func__, ret);
+ return CRYPTO_ERR_SIGNATURE;
+ }
+
+ if ((md_alg != MBEDTLS_MD_SHA256) || (pk_alg != MBEDTLS_PK_ECDSA)) {
+ VERBOSE("%s: md_alg=%u pk_alg=%u\n", __func__, md_alg, pk_alg);
+ return CRYPTO_ERR_SIGNATURE;
+ }
+
+ ret = get_plain_pk_from_asn1(pk_ptr, pk_len, &pk_ptr, &pk_len, &curve_id);
+ if (ret != 0) {
+ VERBOSE("%s: get_plain_pk_from_asn1 (%d)\n", __func__, ret);
+ return CRYPTO_ERR_SIGNATURE;
+ }
+
+ /* We expect a known pk_len */
+ if (pk_len != sizeof(my_pk)) {
+ VERBOSE("%s: pk_len=%u sizeof(my_pk)=%zu)\n", __func__, pk_len, sizeof(my_pk));
+ return CRYPTO_ERR_SIGNATURE;
+ }
+
+ /* Need to copy as auth_ops.verify_signature
+ * expects aligned public key.
+ */
+ memcpy(my_pk, pk_ptr, sizeof(my_pk));
+
+ /* Get the signature (bitstring) */
+ p = (unsigned char *)sig_ptr;
+ end = (unsigned char *)(p + sig_len);
+ ret = mbedtls_asn1_get_bitstring_null(&p, end, &len);
+ if (ret != 0) {
+ VERBOSE("%s: mbedtls_asn1_get_bitstring_null (%d)\n", __func__, ret);
+ return CRYPTO_ERR_SIGNATURE;
+ }
+
+ /* Get r and s from sequence */
+ ret = mbedtls_asn1_get_sequence_of(&p, end, &seq, MBEDTLS_ASN1_INTEGER);
+ if (ret != 0) {
+ VERBOSE("%s: mbedtls_asn1_get_sequence_of (%d)\n", __func__, ret);
+ return CRYPTO_ERR_SIGNATURE;
+ }
+
+ /* We expect only 2 integers (r and s) from the sequence */
+ if (seq.next->next != NULL) {
+ cur = seq.next;
+ mbedtls_asn1_sequence *next;
+
+ VERBOSE("%s: nb seq != 2\n", __func__);
+ /* Free all the sequences */
+ while (cur != NULL) {
+ next = cur->next;
+ mbedtls_free(cur);
+ cur = next;
+ }
+
+ return CRYPTO_ERR_SIGNATURE;
+ }
+
+ /*
+ * ECDSA signatures are composed of a tuple (R,S) where R and S are between 0 and n.
+ * This means that the R and S can have a maximum of 32 each, but can also be smaller.
+ * Also seen the integer sequence may (sometime) start with 0x00 as MSB, but we can only
+ * manage exactly 2*32 bytes, we remove this higher byte if there are not 00,
+ * we will fail either.
+ */
+ cur = &seq;
+ memset(sig, 0U, sizeof(sig));
+
+ while (cur != NULL) {
+ size_t skip = 0U;
+ size_t seek = seq_num * bignum_len;
+
+ if (cur->buf.len > bignum_len) {
+ /* Remove extra 0x00 bytes */
+ skip = cur->buf.len - bignum_len;
+ } else if (cur->buf.len < bignum_len) {
+ /* Add padding to match HW required size */
+ seek += (bignum_len % cur->buf.len);
+ }
+
+ if (seek + cur->buf.len > sizeof(sig) + skip) {
+ panic();
+ }
+
+ memcpy(sig + seek, cur->buf.p + skip, cur->buf.len - skip);
+ cur = cur->next;
+ seq_num++;
+ }
+
+ /* Need to free allocated 'next' in mbedtls_asn1_get_sequence_of */
+ mbedtls_free(seq.next);
+
+ /* Compute hash for the data covered by the signature */
+ stm32_hash_init(HASH_SHA256);
+
+ ret = stm32_hash_final_update((uint8_t *)data_ptr, data_len, image_hash);
+ if (ret != 0) {
+ VERBOSE("%s: stm32_hash_final_update (%d)\n", __func__, ret);
+ return CRYPTO_ERR_SIGNATURE;
+ }
+
+ return verify_signature(image_hash, my_pk, sig, curve_id);
+}
+
+static int crypto_verify_hash(void *data_ptr, unsigned int data_len,
+ void *digest_info_ptr,
+ unsigned int digest_info_len)
+{
+ int ret;
+ uint8_t calc_hash[BOOT_API_SHA256_DIGEST_SIZE_IN_BYTES];
+ unsigned char *p;
+ mbedtls_md_type_t md_alg;
+ size_t len;
+
+ /* we receive an asn1 encapsulated digest, we flatten it */
+ ret = get_plain_digest_from_asn1(digest_info_ptr,
+ digest_info_len, &p, &len,
+ &md_alg);
+ if ((ret != 0) || (md_alg != MBEDTLS_MD_SHA256) || (len != sizeof(calc_hash))) {
+ return CRYPTO_ERR_HASH;
+ }
+
+ digest_info_ptr = p;
+ digest_info_len = len;
+
+ stm32_hash_init(HASH_SHA256);
+
+ ret = stm32_hash_final_update(data_ptr, data_len, calc_hash);
+ if (ret != 0) {
+ VERBOSE("%s: hash failed\n", __func__);
+ return CRYPTO_ERR_HASH;
+ }
+
+ ret = memcmp(calc_hash, digest_info_ptr, digest_info_len);
+ if (ret != 0) {
+ VERBOSE("%s: not expected digest\n", __func__);
+ ret = CRYPTO_ERR_HASH;
+ }
+
+ return ret;
+}
+
+#if !defined(DECRYPTION_SUPPORT_none)
+static int derive_key(uint8_t *key, size_t *key_len, size_t len,
+ unsigned int *flags, const uint8_t *img_id, size_t img_id_len)
+{
+ size_t i, j;
+
+ assert(*key_len >= 32U);
+
+ /*
+ * Not a real derivation yet
+ *
+ * But we expect a 32 bytes key, and OTP is only 16 bytes
+ * => duplicate.
+ */
+ for (i = 0U, j = len; j < 32U;
+ i += sizeof(uint32_t), j += sizeof(uint32_t)) {
+ memcpy(key + j, key + i, sizeof(uint32_t));
+ }
+
+ *key_len = 32U;
+ /* Variable 'key' store a real key */
+ *flags = 0U;
+
+ return 0;
+}
+
+int plat_get_enc_key_info(enum fw_enc_status_t fw_enc_status, uint8_t *key,
+ size_t *key_len, unsigned int *flags,
+ const uint8_t *img_id, size_t img_id_len)
+{
+ uint32_t otp_idx;
+ uint32_t otp_len;
+ size_t read_len;
+ size_t i;
+
+ if (fw_enc_status == FW_ENC_WITH_BSSK) {
+ return -EINVAL;
+ }
+
+ if (stm32_get_otp_index(ENCKEY_OTP, &otp_idx, &otp_len) != 0) {
+ VERBOSE("%s: get %s index error\n", __func__, ENCKEY_OTP);
+ return -EINVAL;
+ }
+
+ if (otp_len > (*key_len * CHAR_BIT)) {
+ VERBOSE("%s: length Error otp_len=%u key_len=%u\n", __func__,
+ otp_len, *key_len * CHAR_BIT);
+ return -EINVAL;
+ }
+
+ read_len = otp_len / CHAR_BIT;
+ assert(read_len % sizeof(uint32_t) == 0);
+
+ for (i = 0U; i < read_len / sizeof(uint32_t); i++) {
+ uint32_t tmp;
+ uint32_t otp_val;
+
+ if (stm32_get_otp_value_from_idx(otp_idx + i, &otp_val) != 0) {
+ zeromem(key, *key_len);
+ VERBOSE("%s: unable to read from otp\n", __func__);
+ return -EINVAL;
+ }
+
+ tmp = bswap32(otp_val);
+ memcpy(key + i * sizeof(uint32_t), &tmp, sizeof(tmp));
+ }
+
+ /* Now we have the OTP values in key till read_len */
+
+ if (derive_key(key, key_len, read_len, flags, img_id,
+ img_id_len) != 0) {
+ zeromem(key, *key_len);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static enum stm32_saes_key_selection select_key(unsigned int key_flags)
+{
+ if ((key_flags & ENC_KEY_IS_IDENTIFIER) != 0U) {
+ panic();
+ }
+
+ /* Use the provided key buffer */
+ return STM32_SAES_KEY_SOFT;
+}
+
+static int stm32_decrypt_aes_gcm(void *data, size_t data_len,
+ const void *key, unsigned int key_len,
+ unsigned int key_flags,
+ const void *iv, unsigned int iv_len,
+ const void *tag, unsigned int tag_len)
+{
+ int ret;
+ struct stm32_saes_context ctx;
+ unsigned char tag_buf[CRYPTO_MAX_TAG_SIZE];
+ enum stm32_saes_key_selection key_mode;
+ unsigned int diff = 0U;
+ unsigned int i;
+
+ key_mode = select_key(key_flags);
+
+ ret = stm32_saes_init(&ctx, true, STM32_SAES_MODE_GCM, key_mode, key,
+ key_len, iv, iv_len);
+ if (ret != 0) {
+ return CRYPTO_ERR_INIT;
+ }
+
+ ret = stm32_saes_update_assodata(&ctx, true, NULL, 0U);
+ if (ret != 0) {
+ return CRYPTO_ERR_DECRYPTION;
+ }
+
+ ret = stm32_saes_update_load(&ctx, true, data, data, data_len);
+ if (ret != 0) {
+ return CRYPTO_ERR_DECRYPTION;
+ }
+
+ ret = stm32_saes_final(&ctx, tag_buf, sizeof(tag_buf));
+ if (ret != 0) {
+ return CRYPTO_ERR_DECRYPTION;
+ }
+
+ /* Check tag in "constant-time" */
+ for (i = 0U; i < tag_len; i++) {
+ diff |= ((const unsigned char *)tag)[i] ^ tag_buf[i];
+ }
+
+ if (diff != 0U) {
+ return CRYPTO_ERR_DECRYPTION;
+ }
+
+ return CRYPTO_SUCCESS;
+}
+
+/*
+ * Authenticated decryption of an image
+ *
+ */
+static int crypto_auth_decrypt(enum crypto_dec_algo dec_algo, void *data_ptr, size_t len,
+ const void *key, unsigned int key_len, unsigned int key_flags,
+ const void *iv, unsigned int iv_len, const void *tag,
+ unsigned int tag_len)
+{
+ int rc = -1;
+ uint32_t real_iv[4];
+
+ switch (dec_algo) {
+ case CRYPTO_GCM_DECRYPT:
+ /*
+ * GCM expect a Nonce
+ * The AES IV is the nonce (a uint32_t[3])
+ * then a counter (a uint32_t big endian)
+ * The counter starts at 2.
+ */
+ memcpy(real_iv, iv, iv_len);
+ real_iv[3] = htobe32(0x2U);
+
+ rc = stm32_decrypt_aes_gcm(data_ptr, len, key, key_len, key_flags,
+ real_iv, sizeof(real_iv), tag, tag_len);
+ break;
+ default:
+ rc = CRYPTO_ERR_DECRYPTION;
+ break;
+ }
+
+ if (rc != 0) {
+ return rc;
+ }
+
+ return CRYPTO_SUCCESS;
+}
+
+REGISTER_CRYPTO_LIB("stm32_crypto_lib",
+ crypto_lib_init,
+ crypto_verify_signature,
+ crypto_verify_hash,
+ crypto_auth_decrypt);
+
+#else /* No decryption support */
+REGISTER_CRYPTO_LIB("stm32_crypto_lib",
+ crypto_lib_init,
+ crypto_verify_signature,
+ crypto_verify_hash,
+ NULL);
+
+#endif
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-23 01:40:50 +0000