summaryrefslogtreecommitdiffstats
path: root/drivers/auth/crypto_mod.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/auth/crypto_mod.c')
-rw-r--r--drivers/auth/crypto_mod.c175
1 files changed, 175 insertions, 0 deletions
diff --git a/drivers/auth/crypto_mod.c b/drivers/auth/crypto_mod.c
new file mode 100644
index 0000000..fa1adb4
--- /dev/null
+++ b/drivers/auth/crypto_mod.c
@@ -0,0 +1,175 @@
+/*
+ * Copyright (c) 2015-2022, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+
+#include <common/debug.h>
+#include <drivers/auth/crypto_mod.h>
+
+/* Variable exported by the crypto library through REGISTER_CRYPTO_LIB() */
+
+/*
+ * The crypto module is responsible for verifying digital signatures and hashes.
+ * It relies on a crypto library to perform the cryptographic operations.
+ *
+ * The crypto module itself does not impose any specific format on signatures,
+ * signature algorithm, keys or hashes, but most cryptographic libraries will
+ * take the parameters as the following DER encoded ASN.1 structures:
+ *
+ * AlgorithmIdentifier ::= SEQUENCE {
+ * algorithm OBJECT IDENTIFIER,
+ * parameters ANY DEFINED BY algorithm OPTIONAL
+ * }
+ *
+ * DigestInfo ::= SEQUENCE {
+ * digestAlgorithm AlgorithmIdentifier,
+ * digest OCTET STRING
+ * }
+ *
+ * SubjectPublicKeyInfo ::= SEQUENCE {
+ * algorithm AlgorithmIdentifier,
+ * subjectPublicKey BIT STRING
+ * }
+ *
+ * SignatureAlgorithm ::= AlgorithmIdentifier
+ *
+ * SignatureValue ::= BIT STRING
+ */
+
+/*
+ * Perform some static checking and call the library initialization function
+ */
+void crypto_mod_init(void)
+{
+ assert(crypto_lib_desc.name != NULL);
+ assert(crypto_lib_desc.init != NULL);
+#if CRYPTO_SUPPORT == CRYPTO_AUTH_VERIFY_ONLY || \
+CRYPTO_SUPPORT == CRYPTO_AUTH_VERIFY_AND_HASH_CALC
+ assert(crypto_lib_desc.verify_signature != NULL);
+ assert(crypto_lib_desc.verify_hash != NULL);
+#endif /* CRYPTO_SUPPORT == CRYPTO_AUTH_VERIFY_ONLY || \
+ CRYPTO_SUPPORT == CRYPTO_AUTH_VERIFY_AND_HASH_CALC */
+
+#if CRYPTO_SUPPORT == CRYPTO_HASH_CALC_ONLY || \
+CRYPTO_SUPPORT == CRYPTO_AUTH_VERIFY_AND_HASH_CALC
+ assert(crypto_lib_desc.calc_hash != NULL);
+#endif /* CRYPTO_SUPPORT == CRYPTO_HASH_CALC_ONLY || \
+ CRYPTO_SUPPORT == CRYPTO_AUTH_VERIFY_AND_HASH_CALC */
+
+ /* Initialize the cryptographic library */
+ crypto_lib_desc.init();
+ INFO("Using crypto library '%s'\n", crypto_lib_desc.name);
+}
+
+#if CRYPTO_SUPPORT == CRYPTO_AUTH_VERIFY_ONLY || \
+CRYPTO_SUPPORT == CRYPTO_AUTH_VERIFY_AND_HASH_CALC
+/*
+ * Function to verify a digital signature
+ *
+ * Parameters:
+ *
+ * data_ptr, data_len: signed data
+ * sig_ptr, sig_len: the digital signature
+ * sig_alg_ptr, sig_alg_len: the digital signature algorithm
+ * pk_ptr, pk_len: the public key
+ */
+int crypto_mod_verify_signature(void *data_ptr, unsigned int data_len,
+ void *sig_ptr, unsigned int sig_len,
+ void *sig_alg_ptr, unsigned int sig_alg_len,
+ void *pk_ptr, unsigned int pk_len)
+{
+ assert(data_ptr != NULL);
+ assert(data_len != 0);
+ assert(sig_ptr != NULL);
+ assert(sig_len != 0);
+ assert(sig_alg_ptr != NULL);
+ assert(sig_alg_len != 0);
+ assert(pk_ptr != NULL);
+ assert(pk_len != 0);
+
+ return crypto_lib_desc.verify_signature(data_ptr, data_len,
+ sig_ptr, sig_len,
+ sig_alg_ptr, sig_alg_len,
+ pk_ptr, pk_len);
+}
+
+/*
+ * Verify a hash by comparison
+ *
+ * Parameters:
+ *
+ * data_ptr, data_len: data to be hashed
+ * digest_info_ptr, digest_info_len: hash to be compared
+ */
+int crypto_mod_verify_hash(void *data_ptr, unsigned int data_len,
+ void *digest_info_ptr, unsigned int digest_info_len)
+{
+ assert(data_ptr != NULL);
+ assert(data_len != 0);
+ assert(digest_info_ptr != NULL);
+ assert(digest_info_len != 0);
+
+ return crypto_lib_desc.verify_hash(data_ptr, data_len,
+ digest_info_ptr, digest_info_len);
+}
+#endif /* CRYPTO_SUPPORT == CRYPTO_AUTH_VERIFY_ONLY || \
+ CRYPTO_SUPPORT == CRYPTO_AUTH_VERIFY_AND_HASH_CALC */
+
+#if CRYPTO_SUPPORT == CRYPTO_HASH_CALC_ONLY || \
+CRYPTO_SUPPORT == CRYPTO_AUTH_VERIFY_AND_HASH_CALC
+/*
+ * Calculate a hash
+ *
+ * Parameters:
+ *
+ * alg: message digest algorithm
+ * data_ptr, data_len: data to be hashed
+ * output: resulting hash
+ */
+int crypto_mod_calc_hash(enum crypto_md_algo alg, void *data_ptr,
+ unsigned int data_len,
+ unsigned char output[CRYPTO_MD_MAX_SIZE])
+{
+ assert(data_ptr != NULL);
+ assert(data_len != 0);
+ assert(output != NULL);
+
+ return crypto_lib_desc.calc_hash(alg, data_ptr, data_len, output);
+}
+#endif /* CRYPTO_SUPPORT == CRYPTO_HASH_CALC_ONLY || \
+ CRYPTO_SUPPORT == CRYPTO_AUTH_VERIFY_AND_HASH_CALC */
+
+/*
+ * Authenticated decryption of data
+ *
+ * Parameters:
+ *
+ * dec_algo: authenticated decryption algorithm
+ * data_ptr, len: data to be decrypted (inout param)
+ * key, key_len, key_flags: symmetric decryption key
+ * iv, iv_len: initialization vector
+ * tag, tag_len: authentication tag
+ */
+int crypto_mod_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)
+{
+ assert(crypto_lib_desc.auth_decrypt != NULL);
+ assert(data_ptr != NULL);
+ assert(len != 0U);
+ assert(key != NULL);
+ assert(key_len != 0U);
+ assert(iv != NULL);
+ assert((iv_len != 0U) && (iv_len <= CRYPTO_MAX_IV_SIZE));
+ assert(tag != NULL);
+ assert((tag_len != 0U) && (tag_len <= CRYPTO_MAX_TAG_SIZE));
+
+ return crypto_lib_desc.auth_decrypt(dec_algo, data_ptr, len, key,
+ key_len, key_flags, iv, iv_len, tag,
+ tag_len);
+}