#!/bin/sh

# Copyright (C) 2016-2020 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/.

# shellcheck disable=SC1091
# SC1091: Not following: ... was not specified as input (see shellcheck -x).

# 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. Use installed version if available and
# use build version if it isn't.
if [ -e ${prefix}/share/kea/scripts/admin-utils.sh ]; then
    . "${prefix}/share/kea/scripts/admin-utils.sh"
else
    . "/build/kea/src/kea-1.9.3/src/bin/admin/admin-utils.sh"
fi

VERSION=$(mysql_version "$@")

if [ "$VERSION" != "4.1" ]; then
    printf 'This script upgrades 4.1 to 5.0. '
    printf 'Reported version is %s. Skipping upgrade.\n' "${VERSION}"
    exit 0
fi

mysql "$@" <<EOF

# Update index used for searching DHCPv4 reservations by identifier and subnet id.
# This index is now unique (to prevent duplicates) and includes DHCPv4 subnet
# identifier.
DROP INDEX key_dhcp4_identifier_subnet_id ON hosts;
CREATE UNIQUE INDEX key_dhcp4_identifier_subnet_id ON hosts (dhcp_identifier ASC , dhcp_identifier_type ASC , dhcp4_subnet_id ASC);

# Update index used for searching DHCPv6 reservations by identifier and subnet id.
# This index is now unique to prevent duplicates.
DROP INDEX key_dhcp6_identifier_subnet_id ON hosts;
CREATE UNIQUE INDEX key_dhcp6_identifier_subnet_id ON hosts (dhcp_identifier ASC , dhcp_identifier_type ASC , dhcp6_subnet_id ASC);

# Create index to search for reservations using IP address and subnet id.
# This unique index guarantees that there is only one occurrence of the
# particular IPv4 address for a given subnet.
CREATE UNIQUE INDEX key_dhcp4_ipv4_address_subnet_id ON hosts (ipv4_address ASC , dhcp4_subnet_id ASC);

# Create index to search for reservations using address/prefix and prefix
# length.
CREATE UNIQUE INDEX key_dhcp6_address_prefix_len ON ipv6_reservations (address ASC , prefix_len ASC);

# Create a table mapping host identifiers to their names. Values in this
# table are used as a foreign key in hosts table to guarantee that only
# identifiers present in host_identifier_type table are used in hosts
# table.
CREATE TABLE IF NOT EXISTS host_identifier_type (
    type TINYINT PRIMARY KEY NOT NULL,   # Lease type code.
    name VARCHAR(32)                     # Name of the lease type
) ENGINE = INNODB;

START TRANSACTION;
INSERT INTO host_identifier_type VALUES (0, 'hw-address'); # Non-temporary v6 addresses
INSERT INTO host_identifier_type VALUES (1, 'duid');       # Temporary v6 addresses
INSERT INTO host_identifier_type VALUES (2, 'circuit-id'); # Prefix delegations
COMMIT;

# Add a constraint that any identifier type value added to the hosts
# must map to a value in the host_identifier_type table.
ALTER TABLE hosts
    ADD CONSTRAINT fk_host_identifier_type FOREIGN KEY (dhcp_identifier_type)
    REFERENCES host_identifier_type (type);

# Store DHCPv6 option code as 16-bit unsigned integer.
ALTER TABLE dhcp6_options MODIFY code SMALLINT UNSIGNED NOT NULL;

# Subnet identifier is unsigned.
ALTER TABLE dhcp4_options MODIFY dhcp4_subnet_id INT UNSIGNED NULL;
ALTER TABLE dhcp6_options MODIFY dhcp6_subnet_id INT UNSIGNED NULL;

# Scopes associate DHCP options stored in dhcp4_options and
# dhcp6_options tables with hosts, subnets, classes or indicate
# that they are global options.
CREATE TABLE IF NOT EXISTS dhcp_option_scope (
    scope_id TINYINT UNSIGNED PRIMARY KEY NOT NULL,
    scope_name VARCHAR(32)
) ENGINE = INNODB;

START TRANSACTION;
INSERT INTO dhcp_option_scope VALUES (0, 'global');
INSERT INTO dhcp_option_scope VALUES (1, 'subnet');
INSERT INTO dhcp_option_scope VALUES (2, 'client-class');
INSERT INTO dhcp_option_scope VALUES (3, 'host');
COMMIT;

# Add scopes into table holding DHCPv4 options
ALTER TABLE dhcp4_options ADD COLUMN scope_id TINYINT UNSIGNED NOT NULL;
ALTER TABLE dhcp4_options
    ADD CONSTRAINT fk_dhcp4_option_scope FOREIGN KEY (scope_id)
    REFERENCES dhcp_option_scope (scope_id);

# Add scopes into table holding DHCPv6 options
ALTER TABLE dhcp6_options ADD COLUMN scope_id TINYINT UNSIGNED NOT NULL;
ALTER TABLE dhcp6_options
    ADD CONSTRAINT fk_dhcp6_option_scope FOREIGN KEY (scope_id)
    REFERENCES dhcp_option_scope (scope_id);

# Add UNSIGNED to reservation_id
ALTER TABLE ipv6_reservations
    MODIFY reservation_id INT UNSIGNED NOT NULL AUTO_INCREMENT;

# Add columns holding reservations for siaddr, sname and file fields
# carried within DHCPv4 message.
ALTER TABLE hosts ADD COLUMN dhcp4_next_server INT UNSIGNED NULL;
ALTER TABLE hosts ADD COLUMN dhcp4_server_hostname VARCHAR(64) NULL;
ALTER TABLE hosts ADD COLUMN dhcp4_boot_file_name VARCHAR(128) NULL;

# Update the schema version number
UPDATE schema_version
SET version = '5', minor = '0';
# This line concludes database upgrade to version 5.0.

EOF
