/**
 * @file smp.h
 * Security Manager Protocol implementation header
 */

/*
 * Copyright (c) 2015 Intel Corporation
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1) Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2) Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * 3) Neither the name of Intel Corporation nor the names of its contributors
 * may be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

struct bt_smp_hdr {
	uint8_t  code;
} __packed;

#define BT_SMP_ERR_PASSKEY_ENTRY_FAILED		0x01
#define BT_SMP_ERR_OOB_NOT_AVAIL		0x02
#define BT_SMP_ERR_AUTH_REQUIREMENTS		0x03
#define BT_SMP_ERR_CONFIRM_FAILED		0x04
#define BT_SMP_ERR_PAIRING_NOTSUPP		0x05
#define BT_SMP_ERR_ENC_KEY_SIZE			0x06
#define BT_SMP_ERR_CMD_NOTSUPP			0x07
#define BT_SMP_ERR_UNSPECIFIED			0x08
#define BT_SMP_ERR_REPEATED_ATTEMPTS		0x09
#define BT_SMP_ERR_INVALID_PARAMS		0x0a
#define BT_SMP_ERR_DHKEY_CHECK_FAILED		0x0b
#define BT_SMP_ERR_NUMERIC_COMP_FAILED		0x0c
#define BT_SMP_ERR_BREDR_PAIRING_IN_PROGRESS	0x0d
#define BT_SMP_ERR_CROSS_TRANSP_NOT_ALLOWED	0x0e

#define BT_SMP_IO_DISPLAY_ONLY			0x00
#define BT_SMP_IO_DISPLAY_YESNO			0x01
#define BT_SMP_IO_KEYBOARD_ONLY			0x02
#define BT_SMP_IO_NO_INPUT_OUTPUT		0x03
#define BT_SMP_IO_KEYBOARD_DISPLAY		0x04

#define BT_SMP_OOB_NOT_PRESENT			0x00
#define BT_SMP_OOB_PRESENT			0x01

#define BT_SMP_MIN_ENC_KEY_SIZE			16
#define BT_SMP_MAX_ENC_KEY_SIZE			16

#define BT_SMP_DIST_ENC_KEY			0x01
#define BT_SMP_DIST_ID_KEY			0x02
#define BT_SMP_DIST_SIGN			0x04
#define BT_SMP_DIST_LINK_KEY			0x08

#define BT_SMP_DIST_MASK			0x0f

#define BT_SMP_AUTH_NONE			0x00
#define BT_SMP_AUTH_BONDING			0x01
#define BT_SMP_AUTH_MITM			0x04
#define BT_SMP_AUTH_SC				0x08
#define BT_SMP_AUTH_KEYPRESS			0x10

#define BT_SMP_AUTH_MASK			0x1f

#define BT_SMP_CMD_PAIRING_REQ			0x01
#define BT_SMP_CMD_PAIRING_RSP			0x02
struct bt_smp_pairing {
	uint8_t  io_capability;
	uint8_t  oob_flag;
	uint8_t  auth_req;
	uint8_t  max_key_size;
	uint8_t  init_key_dist;
	uint8_t  resp_key_dist;
} __packed;

#define BT_SMP_CMD_PAIRING_CONFIRM		0x03
struct bt_smp_pairing_confirm {
	uint8_t  val[16];
} __packed;

#define BT_SMP_CMD_PAIRING_RANDOM		0x04
struct bt_smp_pairing_random {
	uint8_t  val[16];
} __packed;

#define BT_SMP_CMD_PAIRING_FAIL			0x05
struct bt_smp_pairing_fail {
	uint8_t  reason;
} __packed;

#define BT_SMP_CMD_ENCRYPT_INFO			0x06
struct bt_smp_encrypt_info {
	uint8_t  ltk[16];
} __packed;

#define BT_SMP_CMD_MASTER_IDENT			0x07
struct bt_smp_master_ident {
	uint16_t ediv;
	uint64_t rand;
} __packed;

#define BT_SMP_CMD_IDENT_INFO			0x08
struct bt_smp_ident_info {
	uint8_t  irk[16];
} __packed;

#define BT_SMP_CMD_IDENT_ADDR_INFO		0x09
struct bt_smp_ident_addr_info {
	bt_addr_le_t addr;
} __packed;

#define BT_SMP_CMD_SIGNING_INFO			0x0a
struct bt_smp_signing_info {
	uint8_t csrk[16];
} __packed;

#define BT_SMP_CMD_SECURITY_REQUEST		0x0b
struct bt_smp_security_request {
	uint8_t  auth_req;
} __packed;

bool bt_smp_irk_matches(const uint8_t irk[16], const bt_addr_t *addr);
int bt_smp_send_pairing_req(struct bt_conn *conn);
int bt_smp_send_security_req(struct bt_conn *conn);

int bt_smp_init(void);

/** brief Verify signed message
 *
 *  @param conn Bluetooth connection
 *  @param buf received packet buffer with message and signature
 *
 *  @return 0 in success, error code otherwise
 */
int bt_smp_sign_verify(struct bt_conn *conn, struct bt_buf *buf);

/** brief Sign message
 *
 *  @param conn Bluetooth connection
 *  @param buf message buffer
 *
 *  @return 0 in success, error code otherwise
 */
int bt_smp_sign(struct bt_conn *conn, struct bt_buf *buf);