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path: root/drivers/auth/cryptocell/712/cryptocell_crypto.c
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Diffstat (limited to 'drivers/auth/cryptocell/712/cryptocell_crypto.c')
-rw-r--r--drivers/auth/cryptocell/712/cryptocell_crypto.c305
1 files changed, 305 insertions, 0 deletions
diff --git a/drivers/auth/cryptocell/712/cryptocell_crypto.c b/drivers/auth/cryptocell/712/cryptocell_crypto.c
new file mode 100644
index 0000000000..395c550859
--- /dev/null
+++ b/drivers/auth/cryptocell/712/cryptocell_crypto.c
@@ -0,0 +1,305 @@
+/*
+ * Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stddef.h>
+#include <string.h>
+
+#include <platform_def.h>
+
+#include <arch_helpers.h>
+#include <common/debug.h>
+#include <drivers/arm/cryptocell/712/crypto_driver.h>
+#include <drivers/arm/cryptocell/712/rsa.h>
+#include <drivers/arm/cryptocell/712/sbrom_bsv_api.h>
+#include <drivers/arm/cryptocell/712/secureboot_base_func.h>
+#include <drivers/arm/cryptocell/712/secureboot_gen_defs.h>
+#include <drivers/arm/cryptocell/712/util.h>
+#include <drivers/auth/crypto_mod.h>
+#include <drivers/auth/mbedtls/mbedtls_common.h>
+#include <lib/utils.h>
+
+#include <mbedtls/oid.h>
+
+#define LIB_NAME "CryptoCell 712 SBROM"
+#define RSA_SALT_LEN 32
+#define RSA_EXPONENT 65537
+
+/*
+ * AlgorithmIdentifier ::= SEQUENCE {
+ * algorithm OBJECT IDENTIFIER,
+ * parameters ANY DEFINED BY algorithm OPTIONAL
+ * }
+ *
+ * SubjectPublicKeyInfo ::= SEQUENCE {
+ * algorithm AlgorithmIdentifier,
+ * subjectPublicKey BIT STRING
+ * }
+ *
+ * DigestInfo ::= SEQUENCE {
+ * digestAlgorithm AlgorithmIdentifier,
+ * digest OCTET STRING
+ * }
+ *
+ * RSASSA-PSS-params ::= SEQUENCE {
+ * hashAlgorithm [0] HashAlgorithm,
+ * maskGenAlgorithm [1] MaskGenAlgorithm,
+ * saltLength [2] INTEGER,
+ * trailerField [3] TrailerField DEFAULT trailerFieldBC
+ * }
+ */
+
+/*
+ * Initialize the library and export the descriptor
+ */
+static void init(void)
+{
+ CCError_t ret;
+ uint32_t lcs;
+
+ /* Initialize CC SBROM */
+ ret = CC_BsvSbromInit((uintptr_t)PLAT_CRYPTOCELL_BASE);
+ if (ret != CC_OK) {
+ ERROR("CryptoCell CC_BsvSbromInit() error %x\n", ret);
+ panic();
+ }
+
+ /* Initialize lifecycle state */
+ ret = CC_BsvLcsGetAndInit((uintptr_t)PLAT_CRYPTOCELL_BASE, &lcs);
+ if (ret != CC_OK) {
+ ERROR("CryptoCell CC_BsvLcsGetAndInit() error %x\n", ret);
+ panic();
+ }
+
+ /* If the lifecyclestate is `SD`, then stop further execution */
+ if (lcs == CC_BSV_SECURITY_DISABLED_LCS) {
+ ERROR("CryptoCell LCS is security-disabled\n");
+ panic();
+ }
+}
+
+/*
+ * Verify a signature.
+ *
+ * Parameters are passed using the DER encoding format following the ASN.1
+ * structures detailed above.
+ */
+static int 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)
+{
+ CCError_t error;
+ CCSbNParams_t pk;
+ CCSbSignature_t signature;
+ int rc, exp;
+ mbedtls_asn1_buf sig_oid, alg_oid, params;
+ mbedtls_md_type_t md_alg;
+ mbedtls_pk_type_t pk_alg;
+ mbedtls_pk_rsassa_pss_options pss_opts;
+ size_t len;
+ uint8_t *p, *end;
+ /* Temp buf to store the public key modulo (N) in LE format */
+ uint32_t RevN[SB_RSA_MOD_SIZE_IN_WORDS];
+
+ /* Verify the signature algorithm */
+ /* Get pointers to signature OID and parameters */
+ p = sig_alg;
+ end = p + sig_alg_len;
+ rc = mbedtls_asn1_get_alg(&p, end, &sig_oid, &params);
+ if (rc != 0)
+ return CRYPTO_ERR_SIGNATURE;
+
+ /* Get the actual signature algorithm (MD + PK) */
+ rc = mbedtls_oid_get_sig_alg(&sig_oid, &md_alg, &pk_alg);
+ if (rc != 0)
+ return CRYPTO_ERR_SIGNATURE;
+
+ /* The CryptoCell only supports RSASSA-PSS signature */
+ if (pk_alg != MBEDTLS_PK_RSASSA_PSS || md_alg != MBEDTLS_MD_NONE)
+ return CRYPTO_ERR_SIGNATURE;
+
+ /* Verify the RSASSA-PSS params */
+ /* The trailer field is verified to be 0xBC internally by this API */
+ rc = mbedtls_x509_get_rsassa_pss_params(&params, &md_alg,
+ &pss_opts.mgf1_hash_id,
+ &pss_opts.expected_salt_len);
+ if (rc != 0)
+ return CRYPTO_ERR_SIGNATURE;
+
+ /* The CryptoCell only supports SHA256 as hash algorithm */
+ if (md_alg != MBEDTLS_MD_SHA256 || pss_opts.mgf1_hash_id != MBEDTLS_MD_SHA256)
+ return CRYPTO_ERR_SIGNATURE;
+
+ if (pss_opts.expected_salt_len != RSA_SALT_LEN)
+ return CRYPTO_ERR_SIGNATURE;
+
+ /* Parse the public key */
+ p = pk_ptr;
+ end = p + pk_len;
+ rc = mbedtls_asn1_get_tag(&p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
+ if (rc != 0)
+ return CRYPTO_ERR_SIGNATURE;
+
+ end = p + len;
+ rc = mbedtls_asn1_get_alg_null(&p, end, &alg_oid);
+ if (rc != 0)
+ return CRYPTO_ERR_SIGNATURE;
+
+ if (mbedtls_oid_get_pk_alg(&alg_oid, &pk_alg) != 0)
+ return CRYPTO_ERR_SIGNATURE;
+
+ if (pk_alg != MBEDTLS_PK_RSA)
+ return CRYPTO_ERR_SIGNATURE;
+
+ rc = mbedtls_asn1_get_bitstring_null(&p, end, &len);
+ if (rc != 0)
+ return CRYPTO_ERR_SIGNATURE;
+
+ rc = mbedtls_asn1_get_tag(&p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
+ if (rc != 0)
+ return CRYPTO_ERR_SIGNATURE;
+
+ rc = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_INTEGER);
+ if (rc != 0)
+ return CRYPTO_ERR_SIGNATURE;
+
+ if (*p == 0) {
+ p++; len--;
+ }
+ if (len != RSA_MOD_SIZE_IN_BYTES || ((p + len) > end))
+ return CRYPTO_ERR_SIGNATURE;
+
+ /*
+ * The CCSbVerifySignature() API expects N and Np in BE format and
+ * the signature in LE format. Copy N from certificate.
+ */
+ memcpy(pk.N, p, RSA_MOD_SIZE_IN_BYTES);
+
+ /* Verify the RSA exponent */
+ p += len;
+ rc = mbedtls_asn1_get_int(&p, end, &exp);
+ if (rc != 0)
+ return CRYPTO_ERR_SIGNATURE;
+
+ if (exp != RSA_EXPONENT)
+ return CRYPTO_ERR_SIGNATURE;
+
+ /*
+ * Calculate the Np (Barrett n' value). The RSA_CalcNp() API expects
+ * N in LE format. Hence reverse N into a temporary buffer `RevN`.
+ */
+ UTIL_ReverseMemCopy((uint8_t *)RevN, (uint8_t *)pk.N, sizeof(RevN));
+
+ RSA_CalcNp((uintptr_t)PLAT_CRYPTOCELL_BASE, RevN, pk.Np);
+
+ /* Np is in LE format. Reverse it to BE */
+ UTIL_ReverseBuff((uint8_t *)pk.Np, sizeof(pk.Np));
+
+ /* Get the signature (bitstring) */
+ p = sig_ptr;
+ end = p + sig_len;
+ rc = mbedtls_asn1_get_bitstring_null(&p, end, &len);
+ if (rc != 0)
+ return CRYPTO_ERR_SIGNATURE;
+
+ if (len != RSA_MOD_SIZE_IN_BYTES || ((p + len) > end))
+ return CRYPTO_ERR_SIGNATURE;
+
+ /*
+ * The signature is BE format. Convert it to LE before calling
+ * CCSbVerifySignature().
+ */
+ UTIL_ReverseMemCopy((uint8_t *)signature.sig, p, RSA_MOD_SIZE_IN_BYTES);
+
+ /*
+ * CryptoCell utilises DMA internally to transfer data. Flush the data
+ * from caches.
+ */
+ flush_dcache_range((uintptr_t)data_ptr, data_len);
+
+ /* Verify the signature */
+ error = CCSbVerifySignature((uintptr_t)PLAT_CRYPTOCELL_BASE,
+ (uint32_t *)data_ptr, &pk, &signature,
+ data_len, RSA_PSS_2048);
+ if (error != CC_OK)
+ return CRYPTO_ERR_SIGNATURE;
+
+ /* Signature verification success */
+ return CRYPTO_SUCCESS;
+}
+
+/*
+ * Match a hash
+ *
+ * Digest info is passed in DER format following the ASN.1 structure detailed
+ * above.
+ */
+static int verify_hash(void *data_ptr, unsigned int data_len,
+ void *digest_info_ptr, unsigned int digest_info_len)
+{
+ mbedtls_asn1_buf hash_oid, params;
+ mbedtls_md_type_t md_alg;
+ uint8_t *p, *end, *hash;
+ CCHashResult_t pubKeyHash;
+ size_t len;
+ int rc;
+ CCError_t error;
+
+ /* Digest info should be an MBEDTLS_ASN1_SEQUENCE */
+ p = digest_info_ptr;
+ end = p + digest_info_len;
+ rc = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED |
+ MBEDTLS_ASN1_SEQUENCE);
+ if (rc != 0)
+ return CRYPTO_ERR_HASH;
+
+ /* Get the hash algorithm */
+ rc = mbedtls_asn1_get_alg(&p, end, &hash_oid, &params);
+ if (rc != 0)
+ return CRYPTO_ERR_HASH;
+
+ rc = mbedtls_oid_get_md_alg(&hash_oid, &md_alg);
+ if (rc != 0)
+ return CRYPTO_ERR_HASH;
+ /* Verify that hash algorithm is SHA256 */
+ if (md_alg != MBEDTLS_MD_SHA256)
+ return CRYPTO_ERR_HASH;
+
+ /* Hash should be octet string type */
+ rc = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING);
+ if (rc != 0)
+ return CRYPTO_ERR_HASH;
+
+ /* Length of hash must match the algorithm's size */
+ if (len != HASH_RESULT_SIZE_IN_BYTES)
+ return CRYPTO_ERR_HASH;
+
+ /*
+ * CryptoCell utilises DMA internally to transfer data. Flush the data
+ * from caches.
+ */
+ flush_dcache_range((uintptr_t)data_ptr, data_len);
+
+ hash = p;
+ error = SBROM_CryptoHash((uintptr_t)PLAT_CRYPTOCELL_BASE,
+ (uintptr_t)data_ptr, data_len, pubKeyHash);
+ if (error != CC_OK)
+ return CRYPTO_ERR_HASH;
+
+ rc = memcmp(pubKeyHash, hash, HASH_RESULT_SIZE_IN_BYTES);
+ if (rc != 0)
+ return CRYPTO_ERR_HASH;
+
+ return CRYPTO_SUCCESS;
+}
+
+/*
+ * Register crypto library descriptor
+ */
+REGISTER_CRYPTO_LIB(LIB_NAME, init, verify_signature, verify_hash);
+