feat(lib/psa): add measured boot API

A secure enclave could provide an alternate
backend for measured boot. This API can be used
to store measurements in a secure enclave, which
provides the measured boot runtime service.

Signed-off-by: Tamas Ban <tamas.ban@arm.com>
Change-Id: I2448e324e7ece6b318403c5937dfe7abea53d0f3
diff --git a/include/lib/psa/measured_boot.h b/include/lib/psa/measured_boot.h
new file mode 100644
index 0000000..bdb79d5
--- /dev/null
+++ b/include/lib/psa/measured_boot.h
@@ -0,0 +1,77 @@
+/*
+ * Copyright (c) 2022, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+
+#ifndef PSA_MEASURED_BOOT_H
+#define PSA_MEASURED_BOOT_H
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include "psa/error.h"
+
+/* Minimum measurement value size that can be requested to store */
+#define MEASUREMENT_VALUE_MIN_SIZE	32U
+/* Maximum measurement value size that can be requested to store */
+#define MEASUREMENT_VALUE_MAX_SIZE	64U
+/* Minimum signer id size that can be requested to store */
+#define SIGNER_ID_MIN_SIZE		MEASUREMENT_VALUE_MIN_SIZE
+/* Maximum signer id size that can be requested to store */
+#define SIGNER_ID_MAX_SIZE		MEASUREMENT_VALUE_MAX_SIZE
+/* The theoretical maximum image version is: "255.255.65535\0" */
+#define VERSION_MAX_SIZE		14U
+/* Example sw_type: "BL_2, BL_33, etc." */
+#define SW_TYPE_MAX_SIZE		20U
+#define NUM_OF_MEASUREMENT_SLOTS	32U
+
+
+/**
+ * Extends and stores a measurement to the requested slot.
+ *
+ * index			Slot number in which measurement is to be stored
+ * signer_id			Pointer to signer_id buffer.
+ * signer_id_size		Size of the signer_id buffer in bytes.
+ * version			Pointer to version buffer.
+ * version_size			Size of the version buffer in bytes.
+ * measurement_algo		Algorithm identifier used for measurement.
+ * sw_type			Pointer to sw_type buffer.
+ * sw_type_size			Size of the sw_type buffer in bytes.
+ * measurement_value		Pointer to measurement_value buffer.
+ * measurement_value_size	Size of the measurement_value buffer in bytes.
+ * lock_measurement		Boolean flag requesting whether the measurement
+ *				is to be locked.
+ *
+ * PSA_SUCCESS:
+ *	- Success.
+ * PSA_ERROR_INVALID_ARGUMENT:
+ *	- The size of any argument is invalid OR
+ *	- Input Measurement value is NULL OR
+ *	- Input Signer ID is NULL OR
+ *	- Requested slot index is invalid.
+ * PSA_ERROR_BAD_STATE:
+ *	- Request to lock, when slot is already locked.
+ * PSA_ERROR_NOT_PERMITTED:
+ *	- When the requested slot is not accessible to the caller.
+ */
+
+/* Not a standard PSA API, just an extension therefore use the 'rss_' prefix
+ * rather than the usual 'psa_'.
+ */
+psa_status_t
+rss_measured_boot_extend_measurement(uint8_t index,
+				     const uint8_t *signer_id,
+				     size_t signer_id_size,
+				     const uint8_t *version,
+				     size_t version_size,
+				     uint32_t measurement_algo,
+				     const uint8_t *sw_type,
+				     size_t sw_type_size,
+				     const uint8_t *measurement_value,
+				     size_t measurement_value_size,
+				     bool lock_measurement);
+
+#endif /* PSA_MEASURED_BOOT_H */
diff --git a/include/lib/psa/psa/client.h b/include/lib/psa/psa/client.h
new file mode 100644
index 0000000..56fe028
--- /dev/null
+++ b/include/lib/psa/psa/client.h
@@ -0,0 +1,102 @@
+
+/*
+ * Copyright (c) 2018-2021, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+
+#ifndef PSA_CLIENT_H
+#define PSA_CLIENT_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include <psa/error.h>
+
+#ifndef IOVEC_LEN
+#define IOVEC_LEN(arr) ((uint32_t)(sizeof(arr)/sizeof(arr[0])))
+#endif
+/*********************** PSA Client Macros and Types *************************/
+/**
+ * The version of the PSA Framework API that is being used to build the calling
+ * firmware. Only part of features of FF-M v1.1 have been implemented. FF-M v1.1
+ * is compatible with v1.0.
+ */
+#define PSA_FRAMEWORK_VERSION	(0x0101u)
+/**
+ * Return value from psa_version() if the requested RoT Service is not present
+ * in the system.
+ */
+#define PSA_VERSION_NONE	(0u)
+/**
+ * The zero-value null handle can be assigned to variables used in clients and
+ * RoT Services, indicating that there is no current connection or message.
+ */
+#define PSA_NULL_HANDLE		((psa_handle_t)0)
+/**
+ * Tests whether a handle value returned by psa_connect() is valid.
+ */
+#define PSA_HANDLE_IS_VALID(handle)	((psa_handle_t)(handle) > 0)
+/**
+ * Converts the handle value returned from a failed call psa_connect() into
+ * an error code.
+ */
+#define PSA_HANDLE_TO_ERROR(handle)	((psa_status_t)(handle))
+/**
+ * Maximum number of input and output vectors for a request to psa_call().
+ */
+#define PSA_MAX_IOVEC		(4u)
+/**
+ * An IPC message type that indicates a generic client request.
+ */
+#define PSA_IPC_CALL		(0)
+typedef int32_t psa_handle_t;
+/**
+ * A read-only input memory region provided to an RoT Service.
+ */
+typedef struct psa_invec {
+	const void *base;	/*!< the start address of the memory buffer */
+	size_t len;		/*!< the size in bytes                      */
+} psa_invec;
+/**
+ * A writable output memory region provided to an RoT Service.
+ */
+typedef struct psa_outvec {
+	void *base;		/*!< the start address of the memory buffer */
+	size_t len;		/*!< the size in bytes                      */
+} psa_outvec;
+
+/**
+ * Call an RoT Service on an established connection.
+ *
+ * handle	A handle to an established connection.
+ * type		The request type. Must be zero(PSA_IPC_CALL) or positive.
+ * in_vec	Array of input psa_invec structures.
+ * in_len	Number of input psa_invec structures.
+ * out_vec	Array of output psa_outvec structures.
+ * out_len	Number of output psa_outvec structures.
+ *
+ * Return value >=0	RoT Service-specific status value.
+ * Return value <0	RoT Service-specific error code.
+ *
+ * PSA_ERROR_PROGRAMMER_ERROR:
+ *	- The connection has been terminated by the RoT Service.
+ *
+ * The call is a PROGRAMMER ERROR if one or more of the following are true:
+ *	- An invalid handle was passed.
+ *	- The connection is already handling a request.
+ *	- type < 0.
+ *	- An invalid memory reference was provided.
+ *	- in_len + out_len > PSA_MAX_IOVEC.
+ *	- The message is unrecognized by the RoT.
+ *	- Service or incorrectly formatted.
+ */
+psa_status_t psa_call(psa_handle_t handle,
+		      int32_t type,
+		      const psa_invec *in_vec,
+		      size_t in_len,
+		      psa_outvec *out_vec,
+		      size_t out_len);
+
+#endif /* PSA_CLIENT_H */
diff --git a/include/lib/psa/psa/error.h b/include/lib/psa/psa/error.h
new file mode 100644
index 0000000..8a6eb7b
--- /dev/null
+++ b/include/lib/psa/psa/error.h
@@ -0,0 +1,42 @@
+
+/*
+ * Copyright (c) 2019-2021, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+
+#ifndef PSA_ERROR_H
+#define PSA_ERROR_H
+
+#include <stdint.h>
+
+typedef int32_t psa_status_t;
+
+#define PSA_SUCCESS                     ((psa_status_t)0)
+#define PSA_SUCCESS_REBOOT              ((psa_status_t)1)
+#define PSA_SUCCESS_RESTART             ((psa_status_t)2)
+#define PSA_ERROR_PROGRAMMER_ERROR      ((psa_status_t)-129)
+#define PSA_ERROR_CONNECTION_REFUSED    ((psa_status_t)-130)
+#define PSA_ERROR_CONNECTION_BUSY       ((psa_status_t)-131)
+#define PSA_ERROR_GENERIC_ERROR         ((psa_status_t)-132)
+#define PSA_ERROR_NOT_PERMITTED         ((psa_status_t)-133)
+#define PSA_ERROR_NOT_SUPPORTED         ((psa_status_t)-134)
+#define PSA_ERROR_INVALID_ARGUMENT      ((psa_status_t)-135)
+#define PSA_ERROR_INVALID_HANDLE        ((psa_status_t)-136)
+#define PSA_ERROR_BAD_STATE             ((psa_status_t)-137)
+#define PSA_ERROR_BUFFER_TOO_SMALL      ((psa_status_t)-138)
+#define PSA_ERROR_ALREADY_EXISTS        ((psa_status_t)-139)
+#define PSA_ERROR_DOES_NOT_EXIST        ((psa_status_t)-140)
+#define PSA_ERROR_INSUFFICIENT_MEMORY   ((psa_status_t)-141)
+#define PSA_ERROR_INSUFFICIENT_STORAGE  ((psa_status_t)-142)
+#define PSA_ERROR_INSUFFICIENT_DATA     ((psa_status_t)-143)
+#define PSA_ERROR_SERVICE_FAILURE       ((psa_status_t)-144)
+#define PSA_ERROR_COMMUNICATION_FAILURE ((psa_status_t)-145)
+#define PSA_ERROR_STORAGE_FAILURE       ((psa_status_t)-146)
+#define PSA_ERROR_HARDWARE_FAILURE      ((psa_status_t)-147)
+#define PSA_ERROR_INVALID_SIGNATURE     ((psa_status_t)-149)
+#define PSA_ERROR_DEPENDENCY_NEEDED     ((psa_status_t)-156)
+#define PSA_ERROR_CURRENTLY_INSTALLING  ((psa_status_t)-157)
+
+#endif /* PSA_ERROR_H */
diff --git a/include/lib/psa/psa_manifest/sid.h b/include/lib/psa/psa_manifest/sid.h
new file mode 100644
index 0000000..947e58f
--- /dev/null
+++ b/include/lib/psa/psa_manifest/sid.h
@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2019-2022, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+
+#ifndef PSA_MANIFEST_SID_H
+#define PSA_MANIFEST_SID_H
+
+/******** PSA_SP_INITIAL_ATTESTATION ********/
+#define RSS_ATTESTATION_SERVICE_SID			(0x00000020U)
+#define RSS_ATTESTATION_SERVICE_VERSION			(1U)
+#define RSS_ATTESTATION_SERVICE_HANDLE			(0x40000103U)
+
+/******** PSA_SP_MEASURED_BOOT ********/
+#define RSS_MEASURED_BOOT_SID				(0x000000E0U)
+#define RSS_MEASURED_BOOT_VERSION			(1U)
+#define RSS_MEASURED_BOOT_HANDLE			(0x40000104U)
+
+#endif /* PSA_MANIFEST_SID_H */
diff --git a/lib/psa/measured_boot.c b/lib/psa/measured_boot.c
new file mode 100644
index 0000000..f4216eb
--- /dev/null
+++ b/lib/psa/measured_boot.c
@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2022, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+
+#include <string.h>
+
+#include <common/debug.h>
+#include <measured_boot.h>
+#include <psa/client.h>
+#include <psa_manifest/sid.h>
+
+#include "measured_boot_private.h"
+
+static void print_byte_array(const uint8_t *array, size_t len)
+{
+	unsigned int i;
+
+	if (array == NULL || len == 0U) {
+		(void)printf("\n");
+	}
+
+	for (i = 0U; i < len; ++i) {
+		(void)printf(" %02x", array[i]);
+		if ((i & U(0xF)) == U(0xF)) {
+			(void)printf("\n");
+			if (i < (len - 1U)) {
+				INFO("\t\t:");
+			}
+		}
+	}
+}
+
+static void log_measurement(uint8_t index,
+			    const uint8_t *signer_id,
+			    size_t signer_id_size,
+			    const uint8_t *version,     /* string */
+			    uint32_t measurement_algo,
+			    const uint8_t *sw_type,     /* string */
+			    const uint8_t *measurement_value,
+			    size_t measurement_value_size,
+			    bool lock_measurement)
+{
+	INFO("Measured boot extend measurement:\n");
+	INFO(" - slot        : %u\n", index);
+	INFO(" - signer_id   :");
+	print_byte_array(signer_id, signer_id_size);
+	INFO(" - version     : %s\n", version);
+	INFO(" - algorithm   : %x\n", measurement_algo);
+	INFO(" - sw_type     : %s\n", sw_type);
+	INFO(" - measurement :");
+	print_byte_array(measurement_value, measurement_value_size);
+	INFO(" - locking     : %s\n", lock_measurement ? "true" : "false");
+}
+
+psa_status_t
+rss_measured_boot_extend_measurement(uint8_t index,
+				     const uint8_t *signer_id,
+				     size_t signer_id_size,
+				     const uint8_t *version,
+				     size_t version_size,
+				     uint32_t measurement_algo,
+				     const uint8_t *sw_type,
+				     size_t sw_type_size,
+				     const uint8_t *measurement_value,
+				     size_t measurement_value_size,
+				     bool lock_measurement)
+{
+	struct measured_boot_extend_iovec_t extend_iov = {
+		.index = index,
+		.lock_measurement = lock_measurement,
+		.measurement_algo = measurement_algo,
+		.sw_type = {0},
+		.sw_type_size = sw_type_size,
+	};
+
+	psa_invec in_vec[] = {
+		{.base = &extend_iov,
+			.len = sizeof(struct measured_boot_extend_iovec_t)},
+		{.base = signer_id, .len = signer_id_size},
+		{.base = version, .len = version_size},
+		{.base = measurement_value, .len = measurement_value_size}
+	};
+
+	uint32_t sw_type_size_limited;
+
+	if (sw_type != NULL) {
+		sw_type_size_limited = (sw_type_size < SW_TYPE_MAX_SIZE) ?
+					sw_type_size : SW_TYPE_MAX_SIZE;
+		memcpy(extend_iov.sw_type, sw_type, sw_type_size_limited);
+	}
+
+	log_measurement(index, signer_id, signer_id_size,
+			version, measurement_algo, sw_type,
+			measurement_value, measurement_value_size,
+			lock_measurement);
+
+	return psa_call(RSS_MEASURED_BOOT_HANDLE,
+			RSS_MEASURED_BOOT_EXTEND,
+			in_vec, IOVEC_LEN(in_vec),
+			NULL, 0);
+}
diff --git a/lib/psa/measured_boot_private.h b/lib/psa/measured_boot_private.h
new file mode 100644
index 0000000..649c3f6
--- /dev/null
+++ b/lib/psa/measured_boot_private.h
@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2022, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+
+#ifndef PSA_MEASURED_BOOT_PRIVATE_H
+#define PSA_MEASURED_BOOT_PRIVATE_H
+
+#include <stdint.h>
+
+/* Measured boot message types that distinguish its services */
+#define RSS_MEASURED_BOOT_EXTEND	1002U
+
+struct measured_boot_extend_iovec_t {
+	uint8_t  index;
+	uint8_t  lock_measurement;
+	uint32_t measurement_algo;
+	uint8_t  sw_type[SW_TYPE_MAX_SIZE];
+	uint8_t  sw_type_size;
+};
+
+#endif /* PSA_MEASURED_BOOT_PRIVATE_H */