#!/bin/sh

# Copyright (C) 2019-2021 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).

# shellcheck disable=SC2039
# SC2039: In POSIX sh, 'local' is undefined.

# 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-2.0.2/src/bin/admin/admin-utils.sh"
fi

VERSION=$(mysql_version "$@")

if [ "$VERSION" != "8.1" ]; then
    printf 'This script upgrades 8.1 to 8.2. '
    printf 'Reported version is %s. Skipping upgrade.\n' "${VERSION}"
    exit 0
fi

# Get the schema name from database argument. We need this to
# query information_schema for the right database.
for arg in "${@}"
do
    if ! printf '%s' "${arg}" | grep -Eq '^\-\-'
    then
        schema="$arg"
        break
    fi
done

# Make sure we can id the schema
if [ -z "$schema" ]
then
    printf "Could not find database schema name in cmd line args: %s\n" "${*}"
    exit 255
fi

# Save the command line args, as we use these later change_column function.

# Function to rename a column in a table.
change_column() {
    local schema="${1-}"; shift
    local table="${1-}"; shift
    local ocolumn="${1-}"; shift
    local ncolumn="${1-}"; shift

    # First let's find out if the column name in the table actually needs updating.
    sql="select count(column_name) from information_schema.columns where table_schema='$schema' and table_name = '$table' and column_name = '$ocolumn'"
    if ! count=$(mysql -N -B "${@}" -e "${sql}")
    then
        printf 'change_column: schema query failed [%s]\n' "${sql}"
        exit 255
    fi

    # If we found a match record, the column needs to be renamed
    if [ "$count" -eq 1 ]
    then
        sql="ALTER TABLE $table CHANGE COLUMN $ocolumn $ncolumn"
        if ! mysql -N -B "${@}" -e "${sql}"
        then
            printf 'change_column: alter query failed [%s]\n' "${sql}"
            exit 255
        fi
    else
        printf '%s column is already correct\n' "${table}"
    fi
}

mysql "$@" <<EOF

# Drop existing trigger on the dhcp4_shared_network table.
DROP TRIGGER dhcp4_shared_network_ADEL;

# Create new trigger which will delete options associated with the shared
# network.
DELIMITER $$
CREATE TRIGGER dhcp4_shared_network_BDEL BEFORE DELETE ON dhcp4_shared_network
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_shared_network', OLD.id, "delete");
        DELETE FROM dhcp4_options WHERE shared_network_name = OLD.name;
    END $$
DELIMITER ;

# Drop existing trigger on the dhcp4_subnet table.
DROP TRIGGER dhcp4_subnet_ADEL;

# Create new trigger which will delete pools associated with the subnet and
# the options associated with the subnet.
DELIMITER $$
CREATE TRIGGER dhcp4_subnet_BDEL BEFORE DELETE ON dhcp4_subnet
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP4('dhcp4_subnet', OLD.subnet_id, "delete");
        DELETE FROM dhcp4_pool WHERE subnet_id = OLD.subnet_id;
        DELETE FROM dhcp4_options WHERE dhcp4_subnet_id = OLD.subnet_id;
    END $$
DELIMITER ;

# Do not perform cascade deletion of the data in the dhcp4_pool because
# the cascade deletion does not execute triggers associated with the table.
# Instead we are going to use triggers on the dhcp4_subnet table.
ALTER TABLE dhcp4_pool
    DROP FOREIGN KEY fk_dhcp4_pool_subnet_id;

ALTER TABLE dhcp4_pool
    ADD CONSTRAINT fk_dhcp4_pool_subnet_id FOREIGN KEY (subnet_id)
    REFERENCES dhcp4_subnet (subnet_id)
    ON DELETE NO ACTION ON UPDATE CASCADE;

# Drop existing trigger on the dhcp6_shared_network table.
DROP TRIGGER dhcp6_shared_network_ADEL;

# Create new trigger which will delete options associated with the shared
# network.
DELIMITER $$
CREATE TRIGGER dhcp6_shared_network_BDEL BEFORE DELETE ON dhcp6_shared_network
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_shared_network', OLD.id, "delete");
        DELETE FROM dhcp6_options WHERE shared_network_name = OLD.name;
    END $$
DELIMITER ;

# Drop existing trigger on the dhcp6_subnet table.
DROP TRIGGER dhcp6_subnet_ADEL;

# Create new trigger which will delete pools associated with the subnet and
# the options associated with the subnet.
DELIMITER $$
CREATE TRIGGER dhcp6_subnet_BDEL BEFORE DELETE ON dhcp6_subnet
    FOR EACH ROW
    BEGIN
        CALL createAuditEntryDHCP6('dhcp6_subnet', OLD.subnet_id, "delete");
        DELETE FROM dhcp6_pool WHERE subnet_id = OLD.subnet_id;
        DELETE FROM dhcp6_pd_pool WHERE subnet_id = OLD.subnet_id;
        DELETE FROM dhcp6_options WHERE dhcp6_subnet_id = OLD.subnet_id;
    END $$
DELIMITER ;

# Do not perform cascade deletion of the data in the dhcp6_pool and dhcp6_pd_pool
# because the cascaded deletion does not execute triggers associated with the table.
# Instead we are going to use triggers on the dhcp6_subnet table.
ALTER TABLE dhcp6_pool
    DROP FOREIGN KEY fk_dhcp6_pool_subnet_id;

ALTER TABLE dhcp6_pd_pool
    DROP FOREIGN KEY fk_dhcp6_pd_pool_subnet_id;

ALTER TABLE dhcp6_pool
    ADD CONSTRAINT fk_dhcp6_pool_subnet_id FOREIGN KEY (subnet_id)
    REFERENCES dhcp6_subnet (subnet_id)
    ON DELETE NO ACTION 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 NO ACTION ON UPDATE CASCADE;

# Create trigger which removes pool specific options upon removal of
# the pool.
DELIMITER $$
CREATE TRIGGER dhcp6_pd_pool_BDEL BEFORE DELETE ON dhcp6_pd_pool FOR EACH ROW
BEGIN
DELETE FROM dhcp6_options WHERE scope_id = 6 AND pd_pool_id = OLD.id;
END
$$
DELIMITER ;

# Add missing columns in pools.
ALTER TABLE dhcp4_pool
    ADD COLUMN client_class VARCHAR(128) DEFAULT NULL,
    ADD COLUMN require_client_classes LONGTEXT,
    ADD COLUMN user_context LONGTEXT;

ALTER TABLE dhcp6_pd_pool
    ADD COLUMN excluded_prefix VARCHAR(45) DEFAULT NULL,
    ADD COLUMN excluded_prefix_length TINYINT(3) NOT NULL,
    ADD COLUMN client_class VARCHAR(128) DEFAULT NULL,
    ADD COLUMN require_client_classes LONGTEXT,
    ADD COLUMN user_context LONGTEXT;

ALTER TABLE dhcp6_pool
    ADD COLUMN client_class VARCHAR(128) DEFAULT NULL,
    ADD COLUMN require_client_classes LONGTEXT,
    ADD COLUMN user_context LONGTEXT;

-- -----------------------------------------------------
--
-- New version of the createOptionAuditDHCP4 stored
-- procedure which updates modification timestamp of
-- a parent object when an option is modified.
--
-- 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. See dhcp_option_scope
--   for specific values.
-- - 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.
-- - modification_ts: modification timestamp of the
--   option.
-- -----------------------------------------------------
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),
                                        IN modification_ts TIMESTAMP)
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, update
            # the modification timestamp of this subnet to allow the
            # servers to refresh the subnet information. This will
            # also result in creating an audit entry for this subnet.
            UPDATE dhcp4_subnet AS s SET s.modification_ts = modification_ts
                WHERE s.subnet_id = subnet_id;
        ELSEIF scope_id = 4 THEN
            # If shared network specific option is added or modified,
            # update the modification timestamp of this shared network
            # to allow the servers to refresh the shared network
            # information. This will also result in creating an
            # audit entry for this shared network.
           SELECT id INTO snid FROM dhcp4_shared_network WHERE name = network_name LIMIT 1;
           UPDATE dhcp4_shared_network AS n SET n.modification_ts = modification_ts
                WHERE n.id = snid;
        ELSEIF scope_id = 5 THEN
            # If pool specific option is added or modified, update
            # the modification timestamp of the owning subnet.
            SELECT dhcp4_pool.subnet_id INTO sid FROM dhcp4_pool WHERE id = pool_id;
            UPDATE dhcp4_subnet AS s SET s.modification_ts = modification_ts
                WHERE s.subnet_id = sid;
        END IF;
    END IF;
END $$
DELIMITER ;

# Recreate dhcp4_options_AINS trigger to pass timestamp to the updated
# version of the createOptionAuditDHCP4.
DROP TRIGGER IF EXISTS dhcp4_options_AINS;

# This trigger is executed after inserting a DHCPv4 option into the
# database. It creates appropriate audit entry for this option or
# a parent object owning this option.
DELIMITER $$
CREATE TRIGGER dhcp4_options_AINS AFTER INSERT ON dhcp4_options
    FOR EACH ROW
    BEGIN
        CALL createOptionAuditDHCP4("create", NEW.scope_id, NEW.option_id, NEW.dhcp4_subnet_id,
                                    NEW.host_id, NEW.shared_network_name, NEW.pool_id,
                                    NEW.modification_ts);
    END $$
DELIMITER ;

# Recreate dhcp4_options_AUPD trigger to pass timestamp to the updated
# version of the createOptionAuditDHCP4.
DROP TRIGGER IF EXISTS dhcp4_options_AUPD;

# This trigger is executed after updating a DHCPv4 option in the
# database. It creates appropriate audit entry for this option or
# a parent object owning this option.
DELIMITER $$
CREATE TRIGGER dhcp4_options_AUPD AFTER UPDATE ON dhcp4_options
    FOR EACH ROW
    BEGIN
        CALL createOptionAuditDHCP4("update", NEW.scope_id, NEW.option_id, NEW.dhcp4_subnet_id,
                                    NEW.host_id, NEW.shared_network_name, NEW.pool_id,
                                    NEW.modification_ts);
    END $$
DELIMITER ;

# Recreate dhcp4_options_ADEL trigger to pass timestamp to the updated
# version of the createOptionAuditDHCP4.
DROP TRIGGER IF EXISTS dhcp4_options_ADEL;

# This trigger is executed after deleting a DHCPv4 option in the
# database. It creates appropriate audit entry for this option or
# a parent object owning this option.
DELIMITER $$
CREATE TRIGGER dhcp4_options_ADEL AFTER DELETE ON dhcp4_options
    FOR EACH ROW
    BEGIN
        CALL createOptionAuditDHCP4("delete", OLD.scope_id, OLD.option_id, OLD.dhcp4_subnet_id,
                                    OLD.host_id, OLD.shared_network_name, OLD.pool_id,
                                    NOW());
    END $$
DELIMITER ;


-- -----------------------------------------------------
--
-- New version of the createOptionAuditDHCP4 stored
-- procedure which updates modification timestamp of
-- a parent object when an option is modified.
--
-- 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. See dhcp_option_scope
--   for specific values.
-- - 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.
-- - modification_ts: modification timestamp of the
--   option.
-- -----------------------------------------------------
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),
                                        IN modification_ts TIMESTAMP)
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, update
            # the modification timestamp of this subnet to allow the
            # servers to refresh the subnet information. This will
            # also result in creating an audit entry for this subnet.
            UPDATE dhcp6_subnet AS s SET s.modification_ts = modification_ts
                WHERE s.subnet_id = subnet_id;
        ELSEIF scope_id = 4 THEN
            # If shared network specific option is added or modified,
            # update the modification timestamp of this shared network
            # to allow the servers to refresh the shared network
            # information. This will also result in creating an
            # audit entry for this shared network.
           SELECT id INTO snid FROM dhcp6_shared_network WHERE name = network_name LIMIT 1;
           UPDATE dhcp6_shared_network AS n SET n.modification_ts = modification_ts
               WHERE n.id = snid;
        ELSEIF scope_id = 5 THEN
            # If pool specific option is added or modified, update
            # the modification timestamp of the owning subnet.
            SELECT dhcp6_pool.subnet_id INTO sid FROM dhcp6_pool WHERE id = pool_id;
            UPDATE dhcp6_subnet AS s SET s.modification_ts = modification_ts
                WHERE s.subnet_id = sid;
        ELSEIF scope_id = 6 THEN
            # If pd pool specific option is added or modified, create
            # audit entry for the subnet which this pool belongs to.
            SELECT dhcp6_pd_pool.subnet_id INTO sid FROM dhcp6_pd_pool WHERE id = pd_pool_id;
            UPDATE dhcp6_subnet AS s SET s.modification_ts = modification_ts
                WHERE s.subnet_id = sid;
        END IF;
    END IF;
END $$
DELIMITER ;

# Recreate dhcp6_options_AINS trigger to pass timestamp to the updated
# version of the createOptionAuditDHCP6.
DROP TRIGGER IF EXISTS dhcp6_options_AINS;

# This trigger is executed after inserting a DHCPv6 option into the
# database. It creates appropriate audit entry for this option or
# a parent object owning this option.
DELIMITER $$
CREATE TRIGGER dhcp6_options_AINS AFTER INSERT ON dhcp6_options
    FOR EACH ROW
    BEGIN
        CALL createOptionAuditDHCP6("create", NEW.scope_id, NEW.option_id, NEW.dhcp6_subnet_id,
                                    NEW.host_id, NEW.shared_network_name, NEW.pool_id,
                                    NEW.pd_pool_id, NEW.modification_ts);
    END $$
DELIMITER ;

# Recreate dhcp6_options_AUPD trigger to pass timestamp to the updated
# version of the createOptionAuditDHCP6.
DROP TRIGGER IF EXISTS dhcp6_options_AUPD;

# This trigger is executed after updating a DHCPv6 option in the
# database. It creates appropriate audit entry for this option or
# a parent object owning this option.
DELIMITER $$
CREATE TRIGGER dhcp6_options_AUPD AFTER UPDATE ON dhcp6_options
    FOR EACH ROW
    BEGIN
        CALL createOptionAuditDHCP6("update", NEW.scope_id, NEW.option_id, NEW.dhcp6_subnet_id,
                                    NEW.host_id, NEW.shared_network_name, NEW.pool_id,
                                    NEW.pd_pool_id, NEW.modification_ts);
    END $$
DELIMITER ;

# Recreate dhcp6_options_ADEL trigger to pass timestamp to the updated
# version of the createOptionAuditDHCP6.
DROP TRIGGER IF EXISTS dhcp6_options_ADEL;

# This trigger is executed after deleting a DHCPv6 option in the
# database. It creates appropriate audit entry for this option or
# a parent object owning this option.
DELIMITER $$
CREATE TRIGGER dhcp6_options_ADEL AFTER DELETE ON dhcp6_options
    FOR EACH ROW
    BEGIN
        CALL createOptionAuditDHCP6("delete", OLD.scope_id, OLD.option_id, OLD.dhcp6_subnet_id,
                                    OLD.host_id, OLD.shared_network_name, OLD.pool_id,
                                    OLD.pd_pool_id, NOW());
    END $$
DELIMITER ;

# Update the schema version number
UPDATE schema_version
SET version = '8', minor = '2';

# This line concludes database upgrade to version 8.2.

EOF

# We need to rename the columns in the option def tables because "array" is
# a MySQL keyword as of 8.0.17
change_column "${schema}" dhcp4_option_def array "is_array TINYINT(1) NOT NULL" "${@}"
change_column "${schema}" dhcp6_option_def array "is_array TINYINT(1) NOT NULL" "${@}"
