feat(psa): interface with RSS for retrieving ROTPK
Adding the AP/RSS interface for reading the ROTPK.
The read interface implements the psa_call:
psa_call(RSS_CRYPTO_HANDLE, PSA_IPC_CALL,
in_vec, IOVEC_LEN(in_vec),
out_vec, IOVEC_LEN(out_vec));
where the in_vec indicates which of the 3 ROTPKs we want,
and the out_vec stores the ROTPK value we get back from RSS.
Through this service, we will be able to read any of the 3
ROTPKs used on a CCA platform:
- ROTPK for CCA firmware (BL2, BL31, RMM).
- ROTPK for secure firmware.
- ROTPK for non-secure firmware.
Change-Id: I44c615588235cc797fdf38870b74b4c422be0a72
Signed-off-by: Lauren Wehrmeister <lauren.wehrmeister@arm.com>
diff --git a/include/lib/psa/psa_manifest/sid.h b/include/lib/psa/psa_manifest/sid.h
index be78bae..7183112 100644
--- a/include/lib/psa/psa_manifest/sid.h
+++ b/include/lib/psa/psa_manifest/sid.h
@@ -8,6 +8,9 @@
#ifndef PSA_MANIFEST_SID_H
#define PSA_MANIFEST_SID_H
+/******** RSS_SP_CRYPTO ********/
+#define RSS_CRYPTO_HANDLE (0x40000100U)
+
/******** RSS_SP_PLATFORM ********/
#define RSS_PLATFORM_SERVICE_HANDLE (0x40000105U)
diff --git a/include/lib/psa/rss_crypto_defs.h b/include/lib/psa/rss_crypto_defs.h
new file mode 100644
index 0000000..b8c7426
--- /dev/null
+++ b/include/lib/psa/rss_crypto_defs.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2023, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+
+#ifndef RSS_CRYPTO_DEFS_H
+#define RSS_CRYPTO_DEFS_H
+
+/* Declares types that encode errors, algorithms, key types, policies, etc. */
+#include "psa/crypto_types.h"
+
+/*
+ * Value identifying export public key function API, used to dispatch the request
+ * to the corresponding API implementation in the Crypto service backend.
+ *
+ */
+#define RSS_CRYPTO_EXPORT_PUBLIC_KEY_SID (uint16_t)(0x701)
+
+/*
+ * The persistent key identifiers for RSS builtin keys.
+ */
+enum rss_key_id_builtin_t {
+ RSS_BUILTIN_KEY_ID_HOST_S_ROTPK = 0x7FFF816Cu,
+ RSS_BUILTIN_KEY_ID_HOST_NS_ROTPK,
+ RSS_BUILTIN_KEY_ID_HOST_CCA_ROTPK,
+};
+
+/*
+ * This type is used to overcome a limitation within RSS firmware in the number of maximum
+ * IOVECs it can use especially in psa_aead_encrypt and psa_aead_decrypt.
+ */
+#define RSS_CRYPTO_MAX_NONCE_LENGTH (16u)
+struct rss_crypto_aead_pack_input {
+ uint8_t nonce[RSS_CRYPTO_MAX_NONCE_LENGTH];
+ uint32_t nonce_length;
+};
+
+/*
+ * Structure used to pack non-pointer types in a call
+ */
+struct rss_crypto_pack_iovec {
+ psa_key_id_t key_id; /* Key id */
+ psa_algorithm_t alg; /* Algorithm */
+ uint32_t op_handle; /* Frontend context handle associated
+ to a multipart operation */
+ uint32_t capacity; /* Key derivation capacity */
+ uint32_t ad_length; /* Additional Data length for multipart AEAD */
+ uint32_t plaintext_length; /* Plaintext length for multipart AEAD */
+ struct rss_crypto_aead_pack_input aead_in; /* Packs AEAD-related inputs */
+ uint16_t function_id; /* Used to identify the function in the API dispatcher
+ to the service backend. See rss_crypto_func_sid for
+ detail */
+ uint16_t step; /* Key derivation step */
+};
+
+#endif /* RSS_CRYPTO_DEFS_H */
diff --git a/include/lib/psa/rss_platform_api.h b/include/lib/psa/rss_platform_api.h
index 1dd7d05..8f74a51 100644
--- a/include/lib/psa/rss_platform_api.h
+++ b/include/lib/psa/rss_platform_api.h
@@ -11,6 +11,7 @@
#include <stdint.h>
#include "psa/error.h"
+#include <rss_crypto_defs.h>
#define RSS_PLATFORM_API_ID_NV_READ (1010)
#define RSS_PLATFORM_API_ID_NV_INCREMENT (1011)
@@ -41,4 +42,19 @@
rss_platform_nv_counter_read(uint32_t counter_id,
uint32_t size, uint8_t *val);
+/*
+ * Reads the public key or the public part of a key pair in binary format.
+ *
+ * key Identifier of the key to export.
+ * data Buffer where the key data is to be written.
+ * data_size Size of the data buffer in bytes.
+ * data_length On success, the number of bytes that make up the key data.
+ *
+ * PSA_SUCCESS if the value is read correctly. Otherwise,
+ * it returns a PSA_ERROR.
+ */
+psa_status_t
+rss_platform_key_read(enum rss_key_id_builtin_t key, uint8_t *data,
+ size_t data_size, size_t *data_length);
+
#endif /* RSS_PLATFORM_API_H */