/***
  This file is part of systemd.

  Copyright (C) 2013 Intel Corporation. All rights reserved.
  Copyright (C) 2014 Tom Gundersen

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation; either version 2.1 of the License, or
  (at your option) any later version.

  systemd is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/

#include <errno.h>

#include <systemd/sd-dhcp-server.h>
#include <systemd/sd-event.h>

#include "dhcp-server-internal.h"

static void test_pool(struct in_addr *address, unsigned size, int ret) {
        _cleanup_(sd_dhcp_server_unrefp) sd_dhcp_server *server = NULL;

        assert_se(sd_dhcp_server_new(&server, 1) >= 0);

        assert_se(sd_dhcp_server_configure_pool(server, address, 8, 0, size) == ret);
}

static int test_basic(sd_event *event) {
        _cleanup_(sd_dhcp_server_unrefp) sd_dhcp_server *server = NULL;
        struct in_addr address_lo = {
                .s_addr = htonl(INADDR_LOOPBACK),
        };
        struct in_addr address_any = {
                .s_addr = htonl(INADDR_ANY),
        };
        int r;

        /* attach to loopback interface */
        assert_se(sd_dhcp_server_new(&server, 1) >= 0);
        assert_se(server);

        assert_se(sd_dhcp_server_attach_event(server, event, 0) >= 0);
        assert_se(sd_dhcp_server_attach_event(server, event, 0) == -EBUSY);
        assert_se(sd_dhcp_server_get_event(server) == event);
        assert_se(sd_dhcp_server_detach_event(server) >= 0);
        assert_se(!sd_dhcp_server_get_event(server));
        assert_se(sd_dhcp_server_attach_event(server, NULL, 0) >= 0);
        assert_se(sd_dhcp_server_attach_event(server, NULL, 0) == -EBUSY);

        assert_se(sd_dhcp_server_ref(server) == server);
        assert_se(!sd_dhcp_server_unref(server));

        assert_se(sd_dhcp_server_start(server) == -EUNATCH);

        assert_se(sd_dhcp_server_configure_pool(server, &address_any, 28, 0, 0) == -EINVAL);
        assert_se(sd_dhcp_server_configure_pool(server, &address_lo, 38, 0, 0) == -ERANGE);
        assert_se(sd_dhcp_server_configure_pool(server, &address_lo, 8, 0, 0) >= 0);
        assert_se(sd_dhcp_server_configure_pool(server, &address_lo, 8, 0, 0) == -EBUSY);

        test_pool(&address_any, 1, -EINVAL);
        test_pool(&address_lo, 1, 0);

        r = sd_dhcp_server_start(server);

        if (r == -EPERM)
                return EXIT_TEST_SKIP;
        assert_se(r >= 0);

        assert_se(sd_dhcp_server_start(server) == -EBUSY);
        assert_se(sd_dhcp_server_stop(server) >= 0);
        assert_se(sd_dhcp_server_stop(server) >= 0);
        assert_se(sd_dhcp_server_start(server) >= 0);

        return 0;
}

static void test_message_handler(void) {
        _cleanup_(sd_dhcp_server_unrefp) sd_dhcp_server *server = NULL;
        struct {
                DHCPMessage message;
                struct {
                        uint8_t code;
                        uint8_t length;
                        uint8_t type;
                } _packed_ option_type;
                struct {
                        uint8_t code;
                        uint8_t length;
                        be32_t address;
                } _packed_ option_requested_ip;
                struct {
                        uint8_t code;
                        uint8_t length;
                        be32_t address;
                } _packed_ option_server_id;
                struct {
                        uint8_t code;
                        uint8_t length;
                        uint8_t id[7];
                } _packed_ option_client_id;
                uint8_t end;
        } _packed_ test = {
                .message.op = BOOTREQUEST,
                .message.htype = ARPHRD_ETHER,
                .message.hlen = ETHER_ADDR_LEN,
                .message.xid = htobe32(0x12345678),
                .message.chaddr = { 'A', 'B', 'C', 'D', 'E', 'F' },
                .option_type.code = SD_DHCP_OPTION_MESSAGE_TYPE,
                .option_type.length = 1,
                .option_type.type = DHCP_DISCOVER,
                .end = SD_DHCP_OPTION_END,
        };
        struct in_addr address_lo = {
                .s_addr = htonl(INADDR_LOOPBACK),
        };

        assert_se(sd_dhcp_server_new(&server, 1) >= 0);
        assert_se(sd_dhcp_server_configure_pool(server, &address_lo, 8, 0, 0) >= 0);
        assert_se(sd_dhcp_server_attach_event(server, NULL, 0) >= 0);
        assert_se(sd_dhcp_server_start(server) >= 0);

        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == DHCP_OFFER);

        test.end = 0;
        /* TODO, shouldn't this fail? */
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == DHCP_OFFER);
        test.end = SD_DHCP_OPTION_END;
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == DHCP_OFFER);

        test.option_type.code = 0;
        test.option_type.length = 0;
        test.option_type.type = 0;
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == 0);
        test.option_type.code = SD_DHCP_OPTION_MESSAGE_TYPE;
        test.option_type.length = 1;
        test.option_type.type = DHCP_DISCOVER;
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == DHCP_OFFER);

        test.message.op = 0;
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == 0);
        test.message.op = BOOTREQUEST;
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == DHCP_OFFER);

        test.message.htype = 0;
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == 0);
        test.message.htype = ARPHRD_ETHER;
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == DHCP_OFFER);

        test.message.hlen = 0;
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == 0);
        test.message.hlen = ETHER_ADDR_LEN;
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == DHCP_OFFER);

        test.option_type.type = DHCP_REQUEST;
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == 0);
        test.option_requested_ip.code = SD_DHCP_OPTION_REQUESTED_IP_ADDRESS;
        test.option_requested_ip.length = 4;
        test.option_requested_ip.address = htobe32(0x12345678);
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == DHCP_NAK);
        test.option_server_id.code = SD_DHCP_OPTION_SERVER_IDENTIFIER;
        test.option_server_id.length = 4;
        test.option_server_id.address = htobe32(INADDR_LOOPBACK);
        test.option_requested_ip.address = htobe32(INADDR_LOOPBACK + 3);
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == DHCP_ACK);

        test.option_server_id.address = htobe32(0x12345678);
        test.option_requested_ip.address = htobe32(INADDR_LOOPBACK + 3);
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == 0);
        test.option_server_id.address = htobe32(INADDR_LOOPBACK);
        test.option_requested_ip.address = htobe32(INADDR_LOOPBACK + 4);
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == 0);
        test.option_requested_ip.address = htobe32(INADDR_LOOPBACK + 3);
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == DHCP_ACK);

        test.option_client_id.code = SD_DHCP_OPTION_CLIENT_IDENTIFIER;
        test.option_client_id.length = 7;
        test.option_client_id.id[0] = 0x01;
        test.option_client_id.id[1] = 'A';
        test.option_client_id.id[2] = 'B';
        test.option_client_id.id[3] = 'C';
        test.option_client_id.id[4] = 'D';
        test.option_client_id.id[5] = 'E';
        test.option_client_id.id[6] = 'F';
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == DHCP_ACK);

        test.option_requested_ip.address = htobe32(INADDR_LOOPBACK + 30);
        assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == 0);
}

static uint64_t client_id_hash_helper(DHCPClientId *id, uint8_t key[HASH_KEY_SIZE]) {
        struct siphash state;

        siphash24_init(&state, key);
        client_id_hash_func(id, &state);

        return htole64(siphash24_finalize(&state));
}

static void test_client_id_hash(void) {
        DHCPClientId a = {
                .length = 4,
        }, b = {
                .length = 4,
        };
        uint8_t hash_key[HASH_KEY_SIZE] = {
                '0', '1', '2', '3', '4', '5', '6', '7',
                '8', '9', 'A', 'B', 'C', 'D', 'E', 'F',
        };

        a.data = (uint8_t*)strdup("abcd");
        b.data = (uint8_t*)strdup("abcd");

        assert_se(client_id_compare_func(&a, &b) == 0);
        assert_se(client_id_hash_helper(&a, hash_key) == client_id_hash_helper(&b, hash_key));
        a.length = 3;
        assert_se(client_id_compare_func(&a, &b) != 0);
        a.length = 4;
        assert_se(client_id_compare_func(&a, &b) == 0);
        assert_se(client_id_hash_helper(&a, hash_key) == client_id_hash_helper(&b, hash_key));

        b.length = 3;
        assert_se(client_id_compare_func(&a, &b) != 0);
        b.length = 4;
        assert_se(client_id_compare_func(&a, &b) == 0);
        assert_se(client_id_hash_helper(&a, hash_key) == client_id_hash_helper(&b, hash_key));

        free(b.data);
        b.data = (uint8_t*)strdup("abce");
        assert_se(client_id_compare_func(&a, &b) != 0);

        free(a.data);
        free(b.data);
}

int main(int argc, char *argv[]) {
        _cleanup_(sd_event_unrefp) sd_event *e;
        int r;

        log_set_max_level(LOG_DEBUG);
        log_parse_environment();
        log_open();

        assert_se(sd_event_new(&e) >= 0);

        r = test_basic(e);
        if (r != 0)
                return r;

        test_message_handler();
        test_client_id_hash();

        return 0;
}