core/attestation/attestation.h

// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT license.

#ifndef ATTESTATION_H_
#define ATTESTATION_H_

#include <stdint.h>
#include "pcr.h"
#include "crypto/hash.h"
#include "status/rot_status.h"


// Length of challenge nonce in Cerberus Challenge
#define ATTESTATION_NONCE_LEN									SHA256_HASH_LENGTH


/**
 * Key exchange algorithms
 */
enum {
	ATTESTATION_KEY_EXCHANGE_NONE = 0,			/**< No key exchange requested */
	ATTESTATION_ECDHE_KEY_EXCHANGE,				/**< ECDHE key exchange */
	NUM_ATTESTATION_KEY_EXCHANGE_ALGORITHMS,	/**< Number of key exchange algorithms */
};

/**
 * Slot numbers for each supported certificate chain
 */
enum {
	ATTESTATION_RIOT_SLOT_NUM = 0,	/**< Slot number for the RIoT certificate chain */
	ATTESTATION_AUX_SLOT_NUM,		/**< Slot number for the auxiliary certificate chain */
	ATTESTATION_MAX_SLOT_NUM = 7,	/**< The maximum allowed certificate slot number */
};

/**
 * Attestation protocols supported by device
 */
enum attestation_protocol {
	ATTESTATION_PROTOCOL_CERBERUS = 0,	/**< Cerberus challenge protocol */
	ATTESTATION_PROTOCOL_DMTF_SPDM,		/**< DMTF SPDM protocol */
};

/**
 * Attestation protocols spdm minor version numbers
 */
enum attestation_spdm_minor_version {
	ATTESTATION_PROTOCOL_DMTF_SPDM_1_0 = 0,	/**< DMTF SPDM protocol 1.0 */
	ATTESTATION_PROTOCOL_DMTF_SPDM_1_1,		/**< DMTF SPDM protocol 1.1 */
	ATTESTATION_PROTOCOL_DMTF_SPDM_1_2,		/**< DMTF SPDM protocol 1.2 */
};


#pragma pack(push, 1)
/**
 * Challenge nonce.  This follows the format in the Cerberus protocol.
 */
struct attestation_challenge {
	uint8_t slot_num;						/**< The slot number of the chain to use. */
	uint8_t reserved;						/**< Reserved */
	uint8_t nonce[ATTESTATION_NONCE_LEN];	/**< Nonce chosen by requestor. */
};


#define ATTESTATION_CHALLENGE_LEN                               \
		(sizeof (struct attestation_challenge))

/**
 * Challenge attestation response.  This follows the format in the Cerberus protocol.
 */
struct attestation_response {
	uint8_t slot_num;						/**< The slot number of the chain used when generating response. */
	uint8_t slot_mask;						/**< The certificate slot mask. */
	uint8_t min_protocol_version;			/**< Minimum protocol version supported by device. */
	uint8_t max_protocol_version;			/**< Maximum protocol version supported by device. */
	uint16_t reserved;						/**< Reserved. */
	uint8_t nonce[ATTESTATION_NONCE_LEN];	/**< Nonce chosen by responder. */
	uint8_t num_digests;					/**< Number of components used to generate PMR digest. */
	uint8_t digests_size;					/**< Length of PMR digests in bytes. */
};


#define ATTESTATION_CHALLENGE_RSP_LEN                           \
		(sizeof (struct attestation_response))
#pragma pack(pop)

#define	ATTESTATION_ERROR(\
	code)								  ROT_ERROR (ROT_MODULE_ATTESTATION, code)

/**
 * Error codes that can be generated by the attestation manager.
 */
enum {
	ATTESTATION_INVALID_ARGUMENT = ATTESTATION_ERROR (0x00),					/**< Input parameter is null or not valid. */
	ATTESTATION_NO_MEMORY = ATTESTATION_ERROR (0x01),							/**< Memory allocation failed. */
	ATTESTATION_INVALID_SLOT_NUM = ATTESTATION_ERROR (0x02),					/**< Unsupported certificate slot number. */
	ATTESTATION_INVALID_STATE = ATTESTATION_ERROR (0x03),						/**< Invalid state. */
	ATTESTATION_INVALID_DEVICE_NUM = ATTESTATION_ERROR (0x04),					/**< Invalid device number. */
	ATTESTATION_INVALID_CERT_NUM = ATTESTATION_ERROR (0x05),					/**< Invalid certificate number. */
	ATTESTATION_INVALID_DEVICE_ADDR = ATTESTATION_ERROR (0x06),					/**< Unsupported device address. */
	ATTESTATION_UNSUPPORTED_PROTOCOL_VERSION = ATTESTATION_ERROR (0x07),		/**< Unsupported protocol version. */
	ATTESTATION_INVALID_CERT_CHAIN = ATTESTATION_ERROR (0x08),					/**< Invalid certificate chain. */
	ATTESTATION_UNSUPPORTED_ALGORITHM = ATTESTATION_ERROR (0x09),				/**< Unsupported algorithm. */
	// ATTESTATION_INVALID_MEASUREMENT = ATTESTATION_ERROR (0x0A),				/**< Invalid platform measurement. */
	ATTESTATION_BUF_TOO_SMALL = ATTESTATION_ERROR (0x0B),						/**< Provided buffer too small for output. */
	ATTESTATION_CERT_NOT_AVAILABLE = ATTESTATION_ERROR (0x0C),					/**< Certificate queried not found. */
	ATTESTATION_BAD_LENGTH = ATTESTATION_ERROR (0x0D),							/**< The payload length is wrong for the request. */
	ATTESTATION_UNSUPPORTED_OPERATION = ATTESTATION_ERROR (0x0E),				/**< The requested operation is not supported. */
	ATTESTATION_REQUEST_FAILED = ATTESTATION_ERROR (0x0F),						/**< Request to attestation target failed */
	ATTESTATION_UNSUPPORTED_PROTOCOL = ATTESTATION_ERROR (0x10),				/**< Unsupported attestation protocol. */
	ATTESTATION_NO_CFM = ATTESTATION_ERROR (0x11),								/**< No active CFM found. */
	ATTESTATION_CFM_INVALID_ATTESTATION = ATTESTATION_ERROR (0x12),				/**< CFM attestation rule invalid for device being attested. */
	ATTESTATION_CFM_ATTESTATION_RULE_FAIL = ATTESTATION_ERROR (0x13),			/**< CFM attestation rule failed for device being attested. */
	ATTESTATION_ALIAS_KEY_LOAD_FAIL = ATTESTATION_ERROR (0x14),					/**< Failed to load device alias key from device manager. */
	ATTESTATION_REFRESH_ROUTING_TABLE = ATTESTATION_ERROR (0x15),				/**< Updated MCTP bridge routing table needs to be retrieved. */
	ATTESTATION_GET_DEVICE_ID_FAIL = ATTESTATION_ERROR (0x16),					/**< Device failed to send SPDM device ID block. */
	ATTESTATION_TOO_MANY_RETRIES_REQUESTED = ATTESTATION_ERROR (0x17),			/**< Device requested too many ResponseNotReady retries. */
	ATTESTATION_GET_MEAS_OPERATION_UNEXPECTED = ATTESTATION_ERROR (0x18),		/**< Get Measurements response does not perform requested operation. */
	ATTESTATION_GET_MEAS_RSP_NOT_DIGEST = ATTESTATION_ERROR (0x19),				/**< Get Measurements response includes block in raw form when digest requested. */
	ATTESTATION_GET_MEAS_RSP_NOT_RAW = ATTESTATION_ERROR (0x1A),				/**< Get Measurements response includes block in digest form when raw requested. */
	ATTESTATION_GET_MEAS_BLOCKS_TOO_LARGE = ATTESTATION_ERROR (0x1B),			/**< Get Measurements response data larger than internal buffers.*/
	ATTESTATION_DEVICE_NOT_INTEROPERABLE = ATTESTATION_ERROR (0x1C),			/**< Device SPDM version not supported. */
	ATTESTATION_UNEXPECTED_ALG_IN_RESPONSE = ATTESTATION_ERROR (0x1D),			/**< Device response utilizes unexpected algorithm. */
	ATTESTATION_UNSUPPORTED_MEASUREMENT_SPEC = ATTESTATION_ERROR (0x1E),		/**< Unsupported measurement spec utilized by device. */
	// ATTESTATION_GET_CERT_NOT_SUPPORTED_BY_DEVICE = ATTESTATION_ERROR (0x1F),	/**< Device does not support required Get Certificates command.*/
	ATTESTATION_GET_MEAS_NOT_SUPPORTED_BY_DEVICE = ATTESTATION_ERROR (0x20),	/**< Device does not support required Get Measurements command.*/
	ATTESTATION_REQUESTED_SLOT_NUM_EMPTY = ATTESTATION_ERROR (0x21),			/**< Requested certificate slot number empty in response. */
	ATTESTATION_UNEXPECTED_SLOT_NUM = ATTESTATION_ERROR (0x22),					/**< Certificate slot number in response unexpected. */
	ATTESTATION_UNEXPECTED_NUM_MEAS_BLOCKS = ATTESTATION_ERROR (0x23),			/**< Unexpected number of measurement blocks in response. */
	ATTESTATION_CFM_VERSION_SET_SELECTOR_INVALID = ATTESTATION_ERROR (0x24),	/**< CFM version set selector entry invalid. */
	ATTESTATION_FAILED_TO_SELECT_VERSION_SET = ATTESTATION_ERROR (0x25),		/**< Failed to determine device version set using CFM version set selector entry. */
	ATTESTATION_GET_MEAS_CAP_MISMATCH_BY_DEVICE = ATTESTATION_ERROR (0x26),		/**< Target device support mismatched measurement response capabilities. */
	ATTESTATION_CHAL_CAP_MISMATCH_BY_DEVICE = ATTESTATION_ERROR (0x27),			/**< Target device support mismatched challenge response capabilities. */
	ATTESTATION_CERT_TOO_LARGE = ATTESTATION_ERROR (0x28),						/**< A single device cert cannot fit into the message buffer. */
	ATTESTATION_BUFFER_OVERRUN = ATTESTATION_ERROR (0x29),						/**< Buffer overrun occurs when a program accesses memory beyond the allocated buffer size. */
};


#endif	/* ATTESTATION_H_ */