#!/bin/sh

# Copyright (C) 2019-2024 Internet Systems Consortium, Inc. ("ISC")
#
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.

# Exit with error if commands exit with non-zero and if undefined variables are
# used.
set -eu

# shellcheck disable=SC2034
# SC2034: ... appears unused. Verify use (or export if used externally).
prefix="/usr"

# Include utilities based on location of this script. Check for sources first,
# so that the unexpected situations with weird paths fall on the default
# case of installed.
script_path=$(cd "$(dirname "${0}")" && pwd)
if test "${script_path}" = "/build/kea/src/kea-2.6.1/src/share/database/scripts/mysql"; then
    # shellcheck source=./src/bin/admin/admin-utils.sh.in
    . "/build/kea/src/kea-2.6.1/src/bin/admin/admin-utils.sh"
else
    # shellcheck source=./src/bin/admin/admin-utils.sh.in
    . "${prefix}/share/kea/scripts/admin-utils.sh"
fi

VERSION=$(mysql_version "$@")

if [ "$VERSION" != "7.0" ]; then
    printf 'This script upgrades 7.0 to 8.0. '
    printf 'Reported version is %s. Skipping upgrade.\n' "${VERSION}"
    exit 0
fi

mysql "$@" <<EOF
-- This line starts the schema upgrade to version 8.0.

ALTER TABLE dhcp4_options
    MODIFY COLUMN modification_ts TIMESTAMP NOT NULL
    DEFAULT CURRENT_TIMESTAMP;

ALTER TABLE dhcp6_options
    MODIFY COLUMN modification_ts TIMESTAMP NOT NULL
    DEFAULT CURRENT_TIMESTAMP;

ALTER TABLE dhcp4_subnet
    ADD COLUMN authoritative TINYINT(1) DEFAULT NULL,
    ADD COLUMN calculate_tee_times TINYINT(1) DEFAULT NULL,
    ADD COLUMN t1_percent FLOAT DEFAULT NULL,
    ADD COLUMN t2_percent FLOAT DEFAULT NULL;

ALTER TABLE dhcp4_subnet
    MODIFY COLUMN reservation_mode TINYINT(3) DEFAULT NULL;

ALTER TABLE dhcp4_subnet
    MODIFY COLUMN match_client_id TINYINT(1) DEFAULT NULL;

ALTER TABLE dhcp4_shared_network
    ADD COLUMN authoritative TINYINT(1) DEFAULT NULL,
    ADD COLUMN calculate_tee_times TINYINT(1) DEFAULT NULL,
    ADD COLUMN t1_percent FLOAT DEFAULT NULL,
    ADD COLUMN t2_percent FLOAT DEFAULT NULL,
    ADD COLUMN boot_file_name VARCHAR(512) DEFAULT NULL,
    ADD COLUMN next_server INT(10) UNSIGNED DEFAULT NULL,
    ADD COLUMN server_hostname VARCHAR(512) DEFAULT NULL;

ALTER TABLE dhcp4_shared_network
    MODIFY COLUMN reservation_mode TINYINT(3) DEFAULT NULL;

ALTER TABLE dhcp4_shared_network
    MODIFY COLUMN match_client_id TINYINT(1) DEFAULT NULL;

ALTER TABLE dhcp6_subnet
    ADD COLUMN calculate_tee_times TINYINT(1) DEFAULT NULL,
    ADD COLUMN t1_percent FLOAT DEFAULT NULL,
    ADD COLUMN t2_percent FLOAT DEFAULT NULL,
    ADD COLUMN interface_id VARCHAR(128) DEFAULT NULL;

ALTER TABLE dhcp6_subnet
    MODIFY COLUMN reservation_mode TINYINT(3) DEFAULT NULL;

ALTER TABLE dhcp6_subnet
    MODIFY COLUMN rapid_commit TINYINT(1) DEFAULT NULL;

ALTER TABLE dhcp6_shared_network
    ADD COLUMN calculate_tee_times TINYINT(1) DEFAULT NULL,
    ADD COLUMN t1_percent FLOAT DEFAULT NULL,
    ADD COLUMN t2_percent FLOAT DEFAULT NULL,
    ADD COLUMN interface_id VARCHAR(128) DEFAULT NULL;

ALTER TABLE dhcp6_shared_network
    MODIFY COLUMN reservation_mode TINYINT(3) DEFAULT NULL;

ALTER TABLE dhcp6_shared_network
    MODIFY COLUMN rapid_commit TINYINT(1) DEFAULT NULL;

-- -----------------------------------------------------
-- Make sure that constraints on the 7.0 schema tables
-- have appropriate referential actions. All tables
-- which join the configuration elements with the
-- servers should perform cascade deletion.
-- -----------------------------------------------------

ALTER TABLE dhcp4_global_parameter_server
    DROP FOREIGN KEY fk_dhcp4_global_parameter_server_server_id;

ALTER TABLE dhcp4_global_parameter_server
    ADD CONSTRAINT fk_dhcp4_global_parameter_server_server_id
        FOREIGN KEY (server_id)
    REFERENCES dhcp4_server (id)
    ON DELETE CASCADE ON UPDATE NO ACTION;

ALTER TABLE dhcp4_option_def_server
    DROP FOREIGN KEY fk_dhcp4_option_def_server_server_id;

ALTER TABLE dhcp4_option_def_server
    ADD CONSTRAINT fk_dhcp4_option_def_server_server_id
        FOREIGN KEY (server_id)
    REFERENCES dhcp4_server (id)
    ON DELETE CASCADE ON UPDATE NO ACTION;

ALTER TABLE dhcp4_shared_network_server
    DROP FOREIGN KEY fk_dhcp4_shared_network_server_server_id;

ALTER TABLE dhcp4_shared_network_server
    ADD CONSTRAINT fk_dhcp4_shared_network_server_server_id
        FOREIGN KEY (server_id)
    REFERENCES dhcp4_server (id)
    ON DELETE CASCADE ON UPDATE NO ACTION;

ALTER TABLE dhcp4_subnet_server
    DROP FOREIGN KEY fk_dhcp4_subnet_server_server_id;

ALTER TABLE dhcp4_subnet_server
    ADD CONSTRAINT fk_dhcp4_subnet_server_server_id
        FOREIGN KEY (server_id)
    REFERENCES dhcp4_server (id)
    ON DELETE CASCADE ON UPDATE NO ACTION;

ALTER TABLE dhcp4_options_server
    DROP FOREIGN KEY fk_dhcp4_options_server_server_id;

ALTER TABLE dhcp4_options_server
    ADD CONSTRAINT fk_dhcp4_options_server_server_id
        FOREIGN KEY (server_id)
    REFERENCES dhcp4_server (id)
    ON DELETE CASCADE ON UPDATE NO ACTION;

ALTER TABLE dhcp6_global_parameter_server
    DROP FOREIGN KEY fk_dhcp6_global_parameter_server_server_id;

ALTER TABLE dhcp6_global_parameter_server
    ADD CONSTRAINT fk_dhcp6_global_parameter_server_server_id
        FOREIGN KEY (server_id)
    REFERENCES dhcp6_server (id)
    ON DELETE CASCADE ON UPDATE NO ACTION;

ALTER TABLE dhcp6_option_def_server
    DROP FOREIGN KEY fk_dhcp6_option_def_server_server_id;

ALTER TABLE dhcp6_option_def_server
    ADD CONSTRAINT fk_dhcp6_option_def_server_server_id
        FOREIGN KEY (server_id)
    REFERENCES dhcp6_server (id)
    ON DELETE CASCADE ON UPDATE NO ACTION;

ALTER TABLE dhcp6_shared_network_server
    DROP FOREIGN KEY fk_dhcp6_shared_network_server_server_id;

ALTER TABLE dhcp6_shared_network_server
    ADD CONSTRAINT fk_dhcp6_shared_network_server_server_id
        FOREIGN KEY (server_id)
    REFERENCES dhcp6_server (id)
    ON DELETE CASCADE ON UPDATE NO ACTION;

ALTER TABLE dhcp6_subnet_server
    DROP FOREIGN KEY fk_dhcp6_subnet_server_server_id;

ALTER TABLE dhcp6_subnet_server
    ADD CONSTRAINT fk_dhcp6_subnet_server_server_id
        FOREIGN KEY (server_id)
    REFERENCES dhcp6_server (id)
    ON DELETE CASCADE ON UPDATE NO ACTION;

ALTER TABLE dhcp6_options_server
    DROP FOREIGN KEY fk_dhcp6_options_server_option_id;

ALTER TABLE dhcp6_options_server
    ADD CONSTRAINT fk_dhcp6_options_server_option_id
        FOREIGN KEY (option_id)
    REFERENCES dhcp6_options (option_id)
    ON DELETE CASCADE ON UPDATE NO ACTION;

-- -----------------------------------------------------
-- Table dhcp4_audit_revision
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS dhcp4_audit_revision (
    id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
    modification_ts TIMESTAMP NOT NULL,
    log_message TEXT,
    server_id BIGINT(10) UNSIGNED,
    PRIMARY KEY (id),
    KEY key_dhcp4_audit_revision_by_modification_ts (modification_ts)
) ENGINE=InnoDB;

-- -----------------------------------------------------
-- Drop columns from the dhcp4_audit table which now
-- belong to the dhcp4_audit_revision.
-- -----------------------------------------------------
ALTER TABLE dhcp4_audit
    DROP COLUMN modification_ts,
    DROP COLUMN log_message;

-- -----------------------------------------------------
-- Add column revision_id and the foreign key with a
-- reference to the dhcp4_audit_revision table.
-- -----------------------------------------------------
ALTER TABLE dhcp4_audit
    ADD COLUMN revision_id BIGINT(20) UNSIGNED NOT NULL;

ALTER TABLE dhcp4_audit
    ADD CONSTRAINT fk_dhcp4_audit_revision FOREIGN KEY (revision_id)
        REFERENCES dhcp4_audit_revision (id)
        ON DELETE NO ACTION ON UPDATE CASCADE;

-- -----------------------------------------------------
-- Stored procedure which creates a new entry in the
-- dhcp4_audit_revision table and sets appropriate session
-- variables to be used while creating the audit entries
-- by triggers. This procedure should be called at the
-- beginning of a transaction which modifies configuration
-- data in the database, e.g. when new subnet is added.
--
-- Parameters:
-- - audit_ts timestamp to be associated with the audit
--   revision.
-- - server_tag is used to retrieve the server_id which
--   associates the changes applied with the particular
--   server or all servers.
-- - audit_log_message is a log message associates with
--   the audit revision.
-- - cascade_transaction is assigned to a session
--   variable which is used in some triggers to determine
--   if the audit entry should be created for them or
--   not. Specifically, this is used when DHCP options
--   are inserted, updated or deleted. If such modification
--   is a part of the larger change (e.g. change in the
--   subnet the options belong to) the dedicated audit
--   entry for options must not be created. On the other
--   hand, if the global option is being added, the
--   audit entry for the option must be created because
--   it is the sole object modified in that case.
--   Session variable disable_audit is used to disable
--   the procedure when wiping the database during
--   unit tests.  This avoids issues with revision_id
--   being null.
-- -----------------------------------------------------
DROP PROCEDURE IF EXISTS createAuditRevisionDHCP4;
DELIMITER $$
CREATE PROCEDURE createAuditRevisionDHCP4(IN audit_ts TIMESTAMP,
                                          IN server_tag VARCHAR(256),
                                          IN audit_log_message TEXT,
                                          IN cascade_transaction TINYINT(1))
BEGIN
    DECLARE srv_id BIGINT(20);
    IF @disable_audit IS NULL OR @disable_audit = 0 THEN
        SELECT id INTO srv_id FROM dhcp4_server WHERE tag = server_tag;
        INSERT INTO dhcp4_audit_revision (modification_ts, server_id, log_message)
            VALUES (audit_ts, srv_id, audit_log_message);
        SET @audit_revision_id = LAST_INSERT_ID();
        SET @cascade_transaction = cascade_transaction;
    END IF;
END $$
DELIMITER ;

-- -----------------------------------------------------
-- Stored procedure which creates a new entry in the
-- dhcp4_audit table. It should be called from the
-- triggers of the tables where the config modifications
-- are applied. The @audit_revision_id variable contains
-- the revision id to be placed in the audit entries.
--
-- The following parameters are passed to this procedure:
-- - object_type_val: name of the table to be associated
--   with the applied changes.
-- - object_id_val: identifier of the modified object in
--   that table.
-- - modification_type_val: string value indicating the
--   type of the change, i.e. "create", "update" or
--   "delete".
--   Session variable disable_audit is used to disable
--   the procedure when wiping the database during
--   unit tests.  This avoids issues with revision_id
--   being null.
-- ----------------------------------------------------
DROP PROCEDURE IF EXISTS createAuditEntryDHCP4;
DELIMITER $$
CREATE PROCEDURE createAuditEntryDHCP4(IN object_type_val VARCHAR(256),
                                       IN object_id_val BIGINT(20) UNSIGNED,
                                       IN modification_type_val VARCHAR(32))
BEGIN
    IF @disable_audit IS NULL OR @disable_audit = 0 THEN
        INSERT INTO dhcp4_audit (object_type, object_id, modification_type, revision_id)
            VALUES (object_type_val, object_id_val, \
                (SELECT id FROM modification WHERE modification_type = modification_type_val), \
                 @audit_revision_id);
    END IF;
END $$
DELIMITER ;

-- -----------------------------------------------------
-- Triggers used to create entries in the audit
-- tables upon insertion, update or deletion of the
-- configuration entries.
-- -----------------------------------------------------

# Create dhcp4_global_parameter insert trigger
DELIMITER $$
CREATE TRIGGER dhcp4_global_parameter_AINS AFTER INSERT ON dhcp4_global_parameter
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_global_parameter', NEW.id, "create");
    END $$
DELIMITER ;

# Create dhcp4_global_parameter update trigger
DELIMITER $$
CREATE TRIGGER dhcp4_global_parameter_AUPD AFTER UPDATE ON dhcp4_global_parameter
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_global_parameter', NEW.id, "update");
    END $$
DELIMITER ;

# Create dhcp4_global_parameter delete trigger
DELIMITER $$
CREATE TRIGGER dhcp4_global_parameter_ADEL AFTER DELETE ON dhcp4_global_parameter
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_global_parameter', OLD.id, "delete");
    END $$
DELIMITER ;

# Create dhcp4_subnet insert trigger
DELIMITER $$
CREATE TRIGGER dhcp4_subnet_AINS AFTER INSERT ON dhcp4_subnet
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_subnet', NEW.subnet_id, "create");
    END $$
DELIMITER ;

# Create dhcp4_subnet update trigger
DELIMITER $$
CREATE TRIGGER dhcp4_subnet_AUPD AFTER UPDATE ON dhcp4_subnet
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_subnet', NEW.subnet_id, "update");
    END $$
DELIMITER ;

# Create dhcp4_subnet delete trigger
DELIMITER $$
CREATE TRIGGER dhcp4_subnet_ADEL AFTER DELETE ON dhcp4_subnet
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_subnet', OLD.subnet_id, "delete");
    END $$
DELIMITER ;

# Create dhcp4_shared_network insert trigger
DELIMITER $$
CREATE TRIGGER dhcp4_shared_network_AINS AFTER INSERT ON dhcp4_shared_network
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_shared_network', NEW.id, "create");
    END $$
DELIMITER ;

# Create dhcp4_shared_network update trigger
DELIMITER $$
CREATE TRIGGER dhcp4_shared_network_AUPD AFTER UPDATE ON dhcp4_shared_network
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_shared_network', NEW.id, "update");
    END $$
DELIMITER ;

# Create dhcp4_shared_network delete trigger
DELIMITER $$
CREATE TRIGGER dhcp4_shared_network_ADEL AFTER DELETE ON dhcp4_shared_network
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_shared_network', OLD.id, "delete");
    END $$
DELIMITER ;

# Create dhcp4_option_def insert trigger
DELIMITER $$
CREATE TRIGGER dhcp4_option_def_AINS AFTER INSERT ON dhcp4_option_def
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_option_def', NEW.id, "create");
    END $$
DELIMITER ;

# Create dhcp4_option_def update trigger
DELIMITER $$
CREATE TRIGGER dhcp4_option_def_AUPD AFTER UPDATE ON dhcp4_option_def
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_option_def', NEW.id, "update");
    END $$
DELIMITER ;

# Create dhcp4_option_def delete trigger
DELIMITER $$
CREATE TRIGGER dhcp4_option_def_ADEL AFTER DELETE ON dhcp4_option_def
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_option_def', OLD.id, "delete");
    END $$
DELIMITER ;

-- -----------------------------------------------------
-- Stored procedure which creates an audit entry for a
-- DHCPv4 option. Depending on the scope of the option
-- the audit entry can be created for various levels
-- of configuration hierarchy. If this is a global
-- option the audit entry is created for this option
-- for CREATE, UPDATE or DELETE. If the option is being
-- added for an owning option, e.g. for a subnet, the
-- audit entry is created as an UPDATE to this object.
-- From the Kea perspective such option addition will
-- be seen as a subnet update and the server will fetch
-- the whole subnet and merge it into its configuration.
-- The audit entry is not created if it was already
-- created as part of the current transaction.
--
-- The following parameters are passed to the procedure:
-- - modification_type: "create", "update" or "delete"
-- - scope_id: identifier of the option scope, e.g.
--   global, subnet specific etc.
-- - option_id: identifier of the option.
-- - subnet_id: identifier of the subnet if the option
--   belongs to the subnet.
-- - host_id: identifier of the host if the option
-- - belongs to the host.
-- - network_name: shared network name if the option
--   belongs to the shared network.
-- - pool_id: identifier of the pool if the option
--   belongs to the pool.
-- -----------------------------------------------------
DROP PROCEDURE IF EXISTS createOptionAuditDHCP4;
DELIMITER $$
CREATE PROCEDURE createOptionAuditDHCP4(IN modification_type VARCHAR(32),
                                        IN scope_id TINYINT(3) UNSIGNED,
                                        IN option_id BIGINT(20) UNSIGNED,
                                        IN subnet_id INT(10) UNSIGNED,
                                        IN host_id INT(10) UNSIGNED,
                                        IN network_name VARCHAR(128),
                                        IN pool_id BIGINT(20))
BEGIN
    # These variables will hold shared network id and subnet id that
    # we will select.
    DECLARE snid VARCHAR(128);
    DECLARE sid INT(10) UNSIGNED;

    # Cascade transaction flag is set to 1 to prevent creation of
    # the audit entries for the options when the options are
    # created as part of the parent object creation or update.
    # For example: when the option is added as part of the subnet
    # addition, the cascade transaction flag is equal to 1. If
    # the option is added into the existing subnet the cascade
    # transaction is equal to 0. Note that depending on the option
    # scope the audit entry will contain the object_type value
    # of the parent object to cause the server to replace the
    # entire subnet. The only case when the object_type will be
    # set to 'dhcp4_options' is when a global option is added.
    # Global options do not have the owner.
    IF @cascade_transaction IS NULL OR @cascade_transaction = 0 THEN
        # todo: host manager hasn't been updated to use audit
        # mechanisms so ignore host specific options for now.
        IF scope_id = 0 THEN
            # If a global option is added or modified, create audit
            # entry for the 'dhcp4_options' table.
            CALL createAuditEntryDHCP4('dhcp4_options', option_id, modification_type);
        ELSEIF scope_id = 1 THEN
            # If subnet specific option is added or modified, create
            # audit entry for the entire subnet, which indicates that
            # it should be treated as the subnet update.
            CALL createAuditEntryDHCP4('dhcp4_subnet', subnet_id, "update");
        ELSEIF scope_id = 4 THEN
            # If shared network specific option is added or modified,
            # create audit entry for the shared network which
            # indicates that it should be treated as the shared
            # network update.
           SELECT id INTO snid FROM dhcp4_shared_network WHERE name = network_name LIMIT 1;
           CALL createAuditEntryDHCP4('dhcp4_shared_network', snid, "update");
        ELSEIF scope_id = 5 THEN
            # If pool specific option is added or modified, create
            # audit entry for the subnet which this pool belongs to.
            SELECT dhcp4_pool.subnet_id INTO sid FROM dhcp4_pool WHERE id = pool_id;
            CALL createAuditEntryDHCP4('dhcp4_subnet', sid, "update");
        END IF;
    END IF;
END $$
DELIMITER ;

# Create dhcp4_options insert trigger
DELIMITER $$
CREATE TRIGGER dhcp4_options_AINS AFTER INSERT ON dhcp4_options
    FOR EACH ROW
    BEGIN
        CALL createOptionAuditDHCP4("create", NEW.scope_id, NEW.option_id, NEW.dhcp4_subnet_id,
                                    NEW.host_id, NEW.shared_network_name, NEW.pool_id);
    END $$
DELIMITER ;

# Create dhcp4_options update trigger
DELIMITER $$
CREATE TRIGGER dhcp4_options_AUPD AFTER UPDATE ON dhcp4_options
    FOR EACH ROW
    BEGIN
        CALL createOptionAuditDHCP4("update", NEW.scope_id, NEW.option_id, NEW.dhcp4_subnet_id,
                                    NEW.host_id, NEW.shared_network_name, NEW.pool_id);
    END $$
DELIMITER ;

# Create dhcp4_options delete trigger
DELIMITER $$
CREATE TRIGGER dhcp4_options_ADEL AFTER DELETE ON dhcp4_options
    FOR EACH ROW
    BEGIN
        CALL createOptionAuditDHCP4("delete", OLD.scope_id, OLD.option_id, OLD.dhcp4_subnet_id,
                                    OLD.host_id, OLD.shared_network_name, OLD.pool_id);
    END $$
DELIMITER ;

-- -----------------------------------------------------
-- Table parameter_data_type
-- Reflects an enum used by Kea to define supported
-- data types for the simple configuration parameters,
-- e.g. global parameters used by DHCP servers.
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS parameter_data_type (
    id TINYINT UNSIGNED NOT NULL PRIMARY KEY,
    name VARCHAR(32) NOT NULL
) ENGINE = InnoDB;

START TRANSACTION;
INSERT INTO parameter_data_type VALUES (0, 'integer');
INSERT INTO parameter_data_type VALUES (1, 'real');
INSERT INTO parameter_data_type VALUES (2, 'boolean');
INSERT INTO parameter_data_type VALUES (4, 'string');
COMMIT;

ALTER TABLE dhcp4_global_parameter
    ADD COLUMN parameter_type TINYINT UNSIGNED NOT NULL;

ALTER TABLE dhcp4_global_parameter
    ADD CONSTRAINT fk_dhcp4_global_parameter_type FOREIGN KEY (parameter_type)
        REFERENCES parameter_data_type (id);

ALTER TABLE dhcp6_global_parameter
    ADD COLUMN parameter_type TINYINT UNSIGNED NOT NULL;

ALTER TABLE dhcp6_global_parameter
    ADD CONSTRAINT fk_dhcp6_global_parameter_type FOREIGN KEY (parameter_type)
        REFERENCES parameter_data_type (id);

-- Rename dhcp6_subnet_id column of dhcp6_pool and dhcp6_pd_pool

ALTER TABLE dhcp6_pool
    DROP FOREIGN KEY fk_dhcp6_pool_subnet_id;
DROP INDEX fk_dhcp6_pool_subnet_id
    ON dhcp6_pool;

ALTER TABLE dhcp6_pd_pool
    DROP FOREIGN KEY fk_dhcp6_pd_pool_subnet_id;
DROP INDEX fk_dhcp6_pd_pool_subnet_id
    ON dhcp6_pd_pool;

ALTER TABLE dhcp6_pool
    CHANGE dhcp6_subnet_id subnet_id INT(10) UNSIGNED NOT NULL;

ALTER TABLE dhcp6_pd_pool
    CHANGE dhcp6_subnet_id subnet_id INT(10) UNSIGNED NOT NULL;

ALTER TABLE dhcp6_pool
    ADD CONSTRAINT fk_dhcp6_pool_subnet_id
    FOREIGN KEY (subnet_id)
    REFERENCES dhcp6_subnet (subnet_id)
    ON DELETE CASCADE ON UPDATE CASCADE;

ALTER TABLE dhcp6_pd_pool
    ADD CONSTRAINT fk_dhcp6_pd_pool_subnet_id
    FOREIGN KEY (subnet_id)
    REFERENCES dhcp6_subnet (subnet_id)
    ON DELETE CASCADE ON UPDATE CASCADE;

-- align dhcp6_shared_network_server indexes on dhcp4_shared_network_server

ALTER TABLE dhcp6_shared_network_server
    ADD PRIMARY KEY (shared_network_id, server_id);

ALTER TABLE dhcp6_shared_network_server
    DROP FOREIGN KEY fk_dhcp6_shared_network_server_shared_network_id;
DROP INDEX fk_dhcp6_shared_network_server_shared_network_id
    ON dhcp6_shared_network_server;
ALTER TABLE dhcp6_shared_network_server
    ADD CONSTRAINT fk_dhcp6_shared_network_server_shared_network_id
    FOREIGN KEY (shared_network_id)
    REFERENCES dhcp6_shared_network (id)
    ON DELETE CASCADE ON UPDATE NO ACTION;

-- Update dhcp4_subnet_server and dhcp6_subnet_server to allow update
-- on the prefix too by setting the CASCADE action.

ALTER TABLE dhcp4_subnet_server
    DROP FOREIGN KEY fk_dhcp4_subnet_server_subnet_id;
ALTER TABLE dhcp4_subnet_server
    ADD CONSTRAINT fk_dhcp4_subnet_server_subnet_id FOREIGN KEY (subnet_id)
    REFERENCES dhcp4_subnet (subnet_id)
    ON DELETE CASCADE ON UPDATE CASCADE;

ALTER TABLE dhcp6_subnet_server
    DROP FOREIGN KEY fk_dhcp6_subnet_server_subnet_id;
ALTER TABLE dhcp6_subnet_server
    ADD CONSTRAINT fk_dhcp6_subnet_server_subnet_id FOREIGN KEY (subnet_id)
    REFERENCES dhcp6_subnet (subnet_id)
    ON DELETE CASCADE ON UPDATE CASCADE;

-- -----------------------------------------------------
-- Table dhcp6_audit_revision
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS dhcp6_audit_revision (
    id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
    modification_ts TIMESTAMP NOT NULL,
    log_message TEXT,
    server_id BIGINT(10) UNSIGNED,
    PRIMARY KEY (id),
    KEY key_dhcp6_audit_revision_by_modification_ts (modification_ts)
) ENGINE=InnoDB;

-- -----------------------------------------------------
-- Drop columns from the dhcp6_audit table which now
-- belong to the dhcp6_audit_revision.
-- -----------------------------------------------------
ALTER TABLE dhcp6_audit
    DROP COLUMN modification_ts,
    DROP COLUMN log_message;

-- -----------------------------------------------------
-- Add column revision_id and the foreign key with a
-- reference to the dhcp6_audit_revision table.
-- -----------------------------------------------------
ALTER TABLE dhcp6_audit
    ADD COLUMN revision_id BIGINT(20) UNSIGNED NOT NULL;

ALTER TABLE dhcp6_audit
    ADD CONSTRAINT fk_dhcp6_audit_revision FOREIGN KEY (revision_id)
        REFERENCES dhcp6_audit_revision (id)
        ON DELETE NO ACTION ON UPDATE CASCADE;

-- -----------------------------------------------------
-- Stored procedure which creates a new entry in the
-- dhcp6_audit_revision table and sets appropriate session
-- variables to be used while creating the audit entries
-- by triggers. This procedure should be called at the
-- beginning of a transaction which modifies configuration
-- data in the database, e.g. when new subnet is added.
--
-- Parameters:
-- - audit_ts timestamp to be associated with the audit
--   revision.
-- - server_tag is used to retrieve the server_id which
--   associates the changes applied with the particular
--   server or all servers.
-- - audit_log_message is a log message associates with
--   the audit revision.
-- - cascade_transaction is assigned to a session
--   variable which is used in some triggers to determine
--   if the audit entry should be created for them or
--   not. Specifically, this is used when DHCP options
--   are inserted, updated or deleted. If such modification
--   is a part of the larger change (e.g. change in the
--   subnet the options belong to) the dedicated audit
--   entry for options must not be created. On the other
--   hand, if the global option is being added, the
--   audit entry for the option must be created because
--   it is the sole object modified in that case.
--   Session variable disable_audit is used to disable
--   the procedure when wiping the database during
--   unit tests.  This avoids issues with revision_id
--   being null.
-- -----------------------------------------------------
DROP PROCEDURE IF EXISTS createAuditRevisionDHCP6;
DELIMITER $$
CREATE PROCEDURE createAuditRevisionDHCP6(IN audit_ts TIMESTAMP,
                                          IN server_tag VARCHAR(256),
                                          IN audit_log_message TEXT,
                                          IN cascade_transaction TINYINT(1))
BEGIN
    DECLARE srv_id BIGINT(20);
    IF @disable_audit IS NULL OR @disable_audit = 0 THEN
        SELECT id INTO srv_id FROM dhcp6_server WHERE tag = server_tag;
        INSERT INTO dhcp6_audit_revision (modification_ts, server_id, log_message)
            VALUES (audit_ts, srv_id, audit_log_message);
        SET @audit_revision_id = LAST_INSERT_ID();
        SET @cascade_transaction = cascade_transaction;
    END IF;
END $$
DELIMITER ;

-- -----------------------------------------------------
-- Stored procedure which creates a new entry in the
-- dhcp6_audit table. It should be called from the
-- triggers of the tables where the config modifications
-- are applied. The @audit_revision_id variable contains
-- the revision id to be placed in the audit entries.
--
-- The following parameters are passed to this procedure:
-- - object_type_val: name of the table to be associated
--   with the applied changes.
-- - object_id_val: identifier of the modified object in
--   that table.
-- - modification_type_val: string value indicating the
--   type of the change, i.e. "create", "update" or
--   "delete".
--   Session variable disable_audit is used to disable
--   the procedure when wiping the database during
--   unit tests.  This avoids issues with revision_id
--   being null.
-- ----------------------------------------------------
DROP PROCEDURE IF EXISTS createAuditEntryDHCP6;
DELIMITER $$
CREATE PROCEDURE createAuditEntryDHCP6(IN object_type_val VARCHAR(256),
                                       IN object_id_val BIGINT(20) UNSIGNED,
                                       IN modification_type_val VARCHAR(32))
BEGIN
    IF @disable_audit IS NULL OR @disable_audit = 0 THEN
        INSERT INTO dhcp6_audit (object_type, object_id, modification_type, revision_id)
            VALUES (object_type_val, object_id_val, \
               (SELECT id FROM modification WHERE modification_type = modification_type_val), \
                @audit_revision_id);
    END IF;
END $$
DELIMITER ;

-- -----------------------------------------------------
-- Triggers used to create entries in the audit
-- tables upon insertion, update or deletion of the
-- configuration entries.
-- -----------------------------------------------------

# Create dhcp6_global_parameter insert trigger
DELIMITER $$
CREATE TRIGGER dhcp6_global_parameter_AINS AFTER INSERT ON dhcp6_global_parameter
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_global_parameter', NEW.id, "create");
    END $$
DELIMITER ;

# Create dhcp6_global_parameter update trigger
DELIMITER $$
CREATE TRIGGER dhcp6_global_parameter_AUPD AFTER UPDATE ON dhcp6_global_parameter
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_global_parameter', NEW.id, "update");
    END $$
DELIMITER ;

# Create dhcp6_global_parameter delete trigger
DELIMITER $$
CREATE TRIGGER dhcp6_global_parameter_ADEL AFTER DELETE ON dhcp6_global_parameter
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_global_parameter', OLD.id, "delete");
    END $$
DELIMITER ;

# Create dhcp6_subnet insert trigger
DELIMITER $$
CREATE TRIGGER dhcp6_subnet_AINS AFTER INSERT ON dhcp6_subnet
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_subnet', NEW.subnet_id, "create");
    END $$
DELIMITER ;

# Create dhcp6_subnet update trigger
DELIMITER $$
CREATE TRIGGER dhcp6_subnet_AUPD AFTER UPDATE ON dhcp6_subnet
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_subnet', NEW.subnet_id, "update");
    END $$
DELIMITER ;

# Create dhcp6_subnet delete trigger
DELIMITER $$
CREATE TRIGGER dhcp6_subnet_ADEL AFTER DELETE ON dhcp6_subnet
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_subnet', OLD.subnet_id, "delete");
    END $$
DELIMITER ;

# Create dhcp6_shared_network insert trigger
DELIMITER $$
CREATE TRIGGER dhcp6_shared_network_AINS AFTER INSERT ON dhcp6_shared_network
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_shared_network', NEW.id, "create");
    END $$
DELIMITER ;

# Create dhcp6_shared_network update trigger
DELIMITER $$
CREATE TRIGGER dhcp6_shared_network_AUPD AFTER UPDATE ON dhcp6_shared_network
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_shared_network', NEW.id, "update");
    END $$
DELIMITER ;

# Create dhcp6_shared_network delete trigger
DELIMITER $$
CREATE TRIGGER dhcp6_shared_network_ADEL AFTER DELETE ON dhcp6_shared_network
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_shared_network', OLD.id, "delete");
    END $$
DELIMITER ;

# Create dhcp6_option_def insert trigger
DELIMITER $$
CREATE TRIGGER dhcp6_option_def_AINS AFTER INSERT ON dhcp6_option_def
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_option_def', NEW.id, "create");
    END $$
DELIMITER ;

# Create dhcp6_option_def update trigger
DELIMITER $$
CREATE TRIGGER dhcp6_option_def_AUPD AFTER UPDATE ON dhcp6_option_def
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_option_def', NEW.id, "update");
    END $$
DELIMITER ;

# Create dhcp6_option_def delete trigger
DELIMITER $$
CREATE TRIGGER dhcp6_option_def_ADEL AFTER DELETE ON dhcp6_option_def
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_option_def', OLD.id, "delete");
    END $$
DELIMITER ;

-- -----------------------------------------------------
-- Stored procedure which creates an audit entry for a
-- DHCPv6 option. Depending on the scope of the option
-- the audit entry can be created for various levels
-- of configuration hierarchy. If this is a global
-- option the audit entry is created for this option
-- for CREATE, UPDATE or DELETE. If the option is being
-- added for an owning option, e.g. for a subnet, the
-- audit entry is created as an UPDATE to this object.
-- From the Kea perspective such option addition will
-- be seen as a subnet update and the server will fetch
-- the whole subnet and merge it into its configuration.
-- The audit entry is not created if it was already
-- created as part of the current transaction.
--
-- The following parameters are passed to the procedure:
-- - modification_type: "create", "update" or "delete"
-- - scope_id: identifier of the option scope, e.g.
--   global, subnet specific etc.
-- - option_id: identifier of the option.
-- - subnet_id: identifier of the subnet if the option
--   belongs to the subnet.
-- - host_id: identifier of the host if the option
-- - belongs to the host.
-- - network_name: shared network name if the option
--   belongs to the shared network.
-- - pool_id: identifier of the pool if the option
--   belongs to the pool.
-- - pd_pool_id: identifier of the pool if the option
--   belongs to the pd pool.
-- -----------------------------------------------------
DROP PROCEDURE IF EXISTS createOptionAuditDHCP6;
DELIMITER $$
CREATE PROCEDURE createOptionAuditDHCP6(IN modification_type VARCHAR(32),
                                        IN scope_id TINYINT(3) UNSIGNED,
                                        IN option_id BIGINT(20) UNSIGNED,
                                        IN subnet_id INT(10) UNSIGNED,
                                        IN host_id INT(10) UNSIGNED,
                                        IN network_name VARCHAR(128),
                                        IN pool_id BIGINT(20),
                                        IN pd_pool_id BIGINT(20))
BEGIN
    # These variables will hold shared network id and subnet id that
    # we will select.
    DECLARE snid VARCHAR(128);
    DECLARE sid INT(10) UNSIGNED;

    # Cascade transaction flag is set to 1 to prevent creation of
    # the audit entries for the options when the options are
    # created as part of the parent object creation or update.
    # For example: when the option is added as part of the subnet
    # addition, the cascade transaction flag is equal to 1. If
    # the option is added into the existing subnet the cascade
    # transaction is equal to 0. Note that depending on the option
    # scope the audit entry will contain the object_type value
    # of the parent object to cause the server to replace the
    # entire subnet. The only case when the object_type will be
    # set to 'dhcp6_options' is when a global option is added.
    # Global options do not have the owner.
    IF @cascade_transaction IS NULL OR @cascade_transaction = 0 THEN
        # todo: host manager hasn't been updated to use audit
        # mechanisms so ignore host specific options for now.
        IF scope_id = 0 THEN
            # If a global option is added or modified, create audit
            # entry for the 'dhcp6_options' table.
            CALL createAuditEntryDHCP6('dhcp6_options', option_id, modification_type);
        ELSEIF scope_id = 1 THEN
            # If subnet specific option is added or modified, create
            # audit entry for the entire subnet, which indicates that
            # it should be treated as the subnet update.
            CALL createAuditEntryDHCP6('dhcp6_subnet', subnet_id, "update");
        ELSEIF scope_id = 4 THEN
            # If shared network specific option is added or modified,
            # create audit entry for the shared network which
            # indicates that it should be treated as the shared
            # network update.
           SELECT id INTO snid FROM dhcp6_shared_network WHERE name = network_name LIMIT 1;
           CALL createAuditEntryDHCP6('dhcp6_shared_network', snid, "update");
        ELSEIF scope_id = 5 THEN
            # If pool specific option is added or modified, create
            # audit entry for the subnet which this pool belongs to.
            SELECT dhcp6_pool.subnet_id INTO sid FROM dhcp6_pool WHERE id = pool_id;
            CALL createAuditEntryDHCP6('dhcp6_subnet', sid, "update");
        ELSEIF scope_id = 6 THEN
            # If pd pool specific option is added or modified, create
            # audit entry for the subnet which this pd pool belongs to.
            SELECT dhcp6_pd_pool.subnet_id INTO sid FROM dhcp6_pd_pool WHERE id = pd_pool_id;
            CALL createAuditEntryDHCP6('dhcp6_subnet', sid, "update");
        END IF;
    END IF;
END $$
DELIMITER ;

# Create dhcp6_options insert trigger
DELIMITER $$
CREATE TRIGGER dhcp6_options_AINS AFTER INSERT ON dhcp6_options
    FOR EACH ROW
    BEGIN
        CALL createOptionAuditDHCP6("create", NEW.scope_id, NEW.option_id, NEW.dhcp6_subnet_id,
                                    NEW.host_id, NEW.shared_network_name, NEW.pool_id, NEW.pd_pool_id);
    END $$
DELIMITER ;

# Create dhcp6_options update trigger
DELIMITER $$
CREATE TRIGGER dhcp6_options_AUPD AFTER UPDATE ON dhcp6_options
    FOR EACH ROW
    BEGIN
        CALL createOptionAuditDHCP6("update", NEW.scope_id, NEW.option_id, NEW.dhcp6_subnet_id,
                                    NEW.host_id, NEW.shared_network_name, NEW.pool_id, NEW.pd_pool_id);
    END $$
DELIMITER ;

# Create dhcp6_options delete trigger
DELIMITER $$
CREATE TRIGGER dhcp6_options_ADEL AFTER DELETE ON dhcp6_options
    FOR EACH ROW
    BEGIN
        CALL createOptionAuditDHCP6("delete", OLD.scope_id, OLD.option_id, OLD.dhcp6_subnet_id,
                                    OLD.host_id, OLD.shared_network_name, OLD.pool_id, OLD.pd_pool_id);
    END $$
DELIMITER ;

# Update the schema version number.
UPDATE schema_version
    SET version = '8', minor = '0';

# This line concludes the schema upgrade to version 8.0.

EOF
