/***
  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 <stdlib.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <arpa/inet.h>

#include "fileio.h"
#include "unaligned.h"
#include "in-addr-util.h"
#include "hostname-util.h"
#include "dhcp-protocol.h"
#include "dhcp-lease-internal.h"
#include "sd-dhcp-lease.h"
#include "network-internal.h"
#include "dns-domain.h"

int sd_dhcp_lease_get_address(sd_dhcp_lease *lease, struct in_addr *addr) {
        assert_return(lease, -EINVAL);
        assert_return(addr, -EINVAL);

        addr->s_addr = lease->address;

        return 0;
}

int sd_dhcp_lease_get_lifetime(sd_dhcp_lease *lease, uint32_t *lifetime) {
        assert_return(lease, -EINVAL);
        assert_return(lifetime, -EINVAL);

        *lifetime = lease->lifetime;

        return 0;
}

int sd_dhcp_lease_get_mtu(sd_dhcp_lease *lease, uint16_t *mtu) {
        assert_return(lease, -EINVAL);
        assert_return(mtu, -EINVAL);

        if (lease->mtu)
                *mtu = lease->mtu;
        else
                return -ENOENT;

        return 0;
}

int sd_dhcp_lease_get_dns(sd_dhcp_lease *lease, const struct in_addr **addr) {
        assert_return(lease, -EINVAL);
        assert_return(addr, -EINVAL);

        if (lease->dns_size) {
                *addr = lease->dns;
                return lease->dns_size;
        } else
                return -ENOENT;

        return 0;
}

int sd_dhcp_lease_get_ntp(sd_dhcp_lease *lease, const struct in_addr **addr) {
        assert_return(lease, -EINVAL);
        assert_return(addr, -EINVAL);

        if (lease->ntp_size) {
                *addr = lease->ntp;
                return lease->ntp_size;
        } else
                return -ENOENT;

        return 0;
}

int sd_dhcp_lease_get_domainname(sd_dhcp_lease *lease, const char **domainname) {
        assert_return(lease, -EINVAL);
        assert_return(domainname, -EINVAL);

        if (lease->domainname)
                *domainname = lease->domainname;
        else
                return -ENOENT;

        return 0;
}

int sd_dhcp_lease_get_hostname(sd_dhcp_lease *lease, const char **hostname) {
        assert_return(lease, -EINVAL);
        assert_return(hostname, -EINVAL);

        if (lease->hostname)
                *hostname = lease->hostname;
        else
                return -ENOENT;

        return 0;
}

int sd_dhcp_lease_get_root_path(sd_dhcp_lease *lease, const char **root_path) {
        assert_return(lease, -EINVAL);
        assert_return(root_path, -EINVAL);

        if (lease->root_path)
                *root_path = lease->root_path;
        else
                return -ENOENT;

        return 0;
}

int sd_dhcp_lease_get_router(sd_dhcp_lease *lease, struct in_addr *addr) {
        assert_return(lease, -EINVAL);
        assert_return(addr, -EINVAL);

        if (lease->router != INADDR_ANY)
                addr->s_addr = lease->router;
        else
                return -ENOENT;

        return 0;
}

int sd_dhcp_lease_get_netmask(sd_dhcp_lease *lease, struct in_addr *addr) {
        assert_return(lease, -EINVAL);
        assert_return(addr, -EINVAL);

        addr->s_addr = lease->subnet_mask;

        return 0;
}

int sd_dhcp_lease_get_server_identifier(sd_dhcp_lease *lease, struct in_addr *addr) {
        assert_return(lease, -EINVAL);
        assert_return(addr, -EINVAL);

        addr->s_addr = lease->server_address;

        return 0;
}

int sd_dhcp_lease_get_next_server(sd_dhcp_lease *lease, struct in_addr *addr) {
        assert_return(lease, -EINVAL);
        assert_return(addr, -EINVAL);

        addr->s_addr = lease->next_server;

        return 0;
}

int sd_dhcp_lease_get_routes(sd_dhcp_lease *lease, struct sd_dhcp_route **routes) {

        assert_return(lease, -EINVAL);
        assert_return(routes, -EINVAL);

        if (lease->static_route_size) {
                *routes = lease->static_route;
                return lease->static_route_size;
        } else
                return -ENOENT;

        return 0;
}

int sd_dhcp_lease_get_vendor_specific(sd_dhcp_lease *lease, const uint8_t **data,
                                      size_t *data_len) {
        assert_return(lease, -EINVAL);
        assert_return(data, -EINVAL);
        assert_return(data_len, -EINVAL);

        if (!lease->vendor_specific)
                return -ENOENT;

        *data = lease->vendor_specific;
        *data_len = lease->vendor_specific_len;

        return 0;
}

sd_dhcp_lease *sd_dhcp_lease_ref(sd_dhcp_lease *lease) {
        if (lease)
                assert_se(REFCNT_INC(lease->n_ref) >= 2);

        return lease;
}

sd_dhcp_lease *sd_dhcp_lease_unref(sd_dhcp_lease *lease) {
        if (lease && REFCNT_DEC(lease->n_ref) == 0) {
                while (lease->private_options) {
                        struct sd_dhcp_raw_option *option = lease->private_options;

                        LIST_REMOVE(options, lease->private_options, option);

                        free(option->data);
                        free(option);
                }
                free(lease->hostname);
                free(lease->domainname);
                free(lease->dns);
                free(lease->ntp);
                free(lease->static_route);
                free(lease->client_id);
                free(lease->vendor_specific);
                free(lease);
        }

        return NULL;
}

static void lease_parse_u32(const uint8_t *option, size_t len, uint32_t *ret, uint32_t min) {
        assert(option);
        assert(ret);

        if (len == 4) {
                *ret = unaligned_read_be32((be32_t*) option);

                if (*ret < min)
                        *ret = min;
        }
}

static void lease_parse_s32(const uint8_t *option, size_t len, int32_t *ret) {
        lease_parse_u32(option, len, (uint32_t *)ret, 0);
}

static void lease_parse_u16(const uint8_t *option, size_t len, uint16_t *ret, uint16_t min) {
        assert(option);
        assert(ret);

        if (len == 2) {
                *ret = unaligned_read_be16((be16_t*) option);

                if (*ret < min)
                        *ret = min;
        }
}

static void lease_parse_be32(const uint8_t *option, size_t len, be32_t *ret) {
        assert(option);
        assert(ret);

        if (len == 4)
                memcpy(ret, option, 4);
}

static void lease_parse_bool(const uint8_t *option, size_t len, bool *ret) {
        assert(option);
        assert(ret);

        if (len == 1)
                *ret = !!(*option);
}

static void lease_parse_u8(const uint8_t *option, size_t len, uint8_t *ret, uint8_t min) {
        assert(option);
        assert(ret);

        if (len == 1) {
                *ret = *option;

                if (*ret < min)
                        *ret = min;
        }
}

static int lease_parse_string(const uint8_t *option, size_t len, char **ret) {
        assert(option);
        assert(ret);

        if (len >= 1) {
                char *string;

                if (memchr(option, 0, len))
                        return -EINVAL;

                string = strndup((const char *)option, len);
                if (!string)
                        return -ENOMEM;

                free(*ret);
                *ret = string;
        } else
                *ret = mfree(*ret);

        return 0;
}

static int lease_parse_in_addrs_aux(const uint8_t *option, size_t len, struct in_addr **ret, size_t *ret_size, size_t mult) {
        assert(option);
        assert(ret);
        assert(ret_size);

        if (len && !(len % (4 * mult))) {
                size_t size;
                struct in_addr *addresses;

                size = len / 4;

                addresses = newdup(struct in_addr, option, size);
                if (!addresses)
                        return -ENOMEM;

                free(*ret);
                *ret = addresses;
                *ret_size = size;
        }

        return 0;
}

static int lease_parse_in_addrs(const uint8_t *option, size_t len, struct in_addr **ret, size_t *ret_size) {
        return lease_parse_in_addrs_aux(option, len, ret, ret_size, 1);
}

static int lease_parse_in_addrs_pairs(const uint8_t *option, size_t len, struct in_addr **ret, size_t *ret_size) {
        return lease_parse_in_addrs_aux(option, len, ret, ret_size, 2);
}

static int lease_parse_routes(const uint8_t *option, size_t len, struct sd_dhcp_route **routes,
        size_t *routes_size, size_t *routes_allocated) {

        struct in_addr addr;

        assert(option);
        assert(routes);
        assert(routes_size);
        assert(routes_allocated);

        if (!len)
                return 0;

        if (len % 8 != 0)
                return -EINVAL;

        if (!GREEDY_REALLOC(*routes, *routes_allocated, *routes_size + (len / 8)))
                return -ENOMEM;

        while (len >= 8) {
                struct sd_dhcp_route *route = *routes + *routes_size;
                int r;

                r = in_addr_default_prefixlen((struct in_addr*) option, &route->dst_prefixlen);
                if (r < 0) {
                        log_error("Failed to determine destination prefix length from class based IP, ignoring");
                        continue;
                }

                lease_parse_be32(option, 4, &addr.s_addr);
                route->dst_addr = inet_makeaddr(inet_netof(addr), 0);
                option += 4;

                lease_parse_be32(option, 4, &route->gw_addr.s_addr);
                option += 4;

                len -= 8;
                (*routes_size)++;
        }

        return 0;
}

/* parses RFC3442 Classless Static Route Option */
static int lease_parse_classless_routes(const uint8_t *option, size_t len, struct sd_dhcp_route **routes,
        size_t *routes_size, size_t *routes_allocated) {

        assert(option);
        assert(routes);
        assert(routes_size);
        assert(routes_allocated);

        /* option format: (subnet-mask-width significant-subnet-octets gateway-ip)*  */

        while (len > 0) {
                uint8_t dst_octets;
                struct sd_dhcp_route *route;

                if (!GREEDY_REALLOC(*routes, *routes_allocated, *routes_size + 1))
                    return -ENOMEM;

                route = *routes + *routes_size;

                dst_octets = (*option == 0 ? 0 : ((*option - 1) / 8) + 1);
                route->dst_prefixlen = *option;
                option++;
                len--;

                /* can't have more than 4 octets in IPv4 */
                if (dst_octets > 4 || len < dst_octets)
                        return -EINVAL;

                route->dst_addr.s_addr = 0;
                memcpy(&route->dst_addr.s_addr, option, dst_octets);
                option += dst_octets;
                len -= dst_octets;

                if (len < 4)
                        return -EINVAL;

                lease_parse_be32(option, 4, &route->gw_addr.s_addr);
                option += 4;
                len -= 4;

                (*routes_size)++;
        }

        return 0;
}

int dhcp_lease_parse_options(uint8_t code, uint8_t len, const uint8_t *option, void *userdata) {
        sd_dhcp_lease *lease = userdata;
        int r;

        assert(lease);

        switch(code) {

        case DHCP_OPTION_TIME_OFFSET:
                lease_parse_s32(option, len, &lease->time_offset);
                break;

        case DHCP_OPTION_INTERFACE_MTU_AGING_TIMEOUT:
                lease_parse_u32(option, len, &lease->mtu_aging_timeout, 0);
                break;

        case DHCP_OPTION_IP_ADDRESS_LEASE_TIME:
                lease_parse_u32(option, len, &lease->lifetime, 1);
                break;

        case DHCP_OPTION_SERVER_IDENTIFIER:
                lease_parse_be32(option, len, &lease->server_address);
                break;

        case DHCP_OPTION_SUBNET_MASK:
                lease_parse_be32(option, len, &lease->subnet_mask);
                break;

        case DHCP_OPTION_BROADCAST:
                lease_parse_be32(option, len, &lease->broadcast);
                break;

        case DHCP_OPTION_ROUTER:
                if (len >= 4)
                        lease_parse_be32(option, 4, &lease->router);

                break;

        case DHCP_OPTION_DOMAIN_NAME_SERVER:
                return lease_parse_in_addrs(option, len, &lease->dns, &lease->dns_size);

        case DHCP_OPTION_NTP_SERVER:
                return lease_parse_in_addrs(option, len, &lease->ntp, &lease->ntp_size);

        case DHCP_OPTION_POLICY_FILTER:
                return lease_parse_in_addrs_pairs(option, len, &lease->policy_filter, &lease->policy_filter_size);

        case DHCP_OPTION_STATIC_ROUTE:
                return lease_parse_routes(option, len, &lease->static_route, &lease->static_route_size, &lease->static_route_allocated);

        case DHCP_OPTION_INTERFACE_MTU:
                lease_parse_u16(option, len, &lease->mtu, 68);
                break;

        case DHCP_OPTION_INTERFACE_MDR:
                lease_parse_u16(option, len, &lease->mdr, 576);
                break;

        case DHCP_OPTION_INTERFACE_TTL:
                lease_parse_u8(option, len, &lease->ttl, 1);
                break;

        case DHCP_OPTION_BOOT_FILE_SIZE:
                lease_parse_u16(option, len, &lease->boot_file_size, 0);
                break;

        case DHCP_OPTION_DOMAIN_NAME: {
                _cleanup_free_ char *domainname = NULL, *normalized = NULL;

                r = lease_parse_string(option, len, &domainname);
                if (r < 0)
                        return r;

                r = dns_name_normalize(domainname, &normalized);
                if (r < 0) {
                        log_debug_errno(r, "Failed to normalize domain name '%s': %m", domainname);
                        return 0;
                }

                if (is_localhost(normalized)) {
                        log_debug_errno(r, "Detected 'localhost' as suggested hostname, ignoring.");
                        break;
                }

                free(lease->domainname);
                lease->domainname = normalized;
                normalized = NULL;

                break;
        }

        case DHCP_OPTION_HOST_NAME: {
                _cleanup_free_ char *hostname = NULL, *normalized = NULL;

                r = lease_parse_string(option, len, &hostname);
                if (r < 0)
                        return r;

                r = dns_name_normalize(hostname, &normalized);
                if (r < 0) {
                        log_debug_errno(r, "Failed to normalize host name '%s': %m", hostname);
                        return 0;
                }

                if (is_localhost(normalized)) {
                        log_debug_errno(r, "Detected 'localhost' as suggested hostname, ignoring.");
                        return 0;
                }

                free(lease->hostname);
                lease->hostname = normalized;
                normalized = NULL;

                break;
        }

        case DHCP_OPTION_ROOT_PATH:
                return lease_parse_string(option, len, &lease->root_path);

        case DHCP_OPTION_RENEWAL_T1_TIME:
                lease_parse_u32(option, len, &lease->t1, 1);
                break;

        case DHCP_OPTION_REBINDING_T2_TIME:
                lease_parse_u32(option, len, &lease->t2, 1);
                break;

        case DHCP_OPTION_ENABLE_IP_FORWARDING:
                lease_parse_bool(option, len, &lease->ip_forward);
                break;

        case DHCP_OPTION_ENABLE_IP_FORWARDING_NL:
                lease_parse_bool(option, len, &lease->ip_forward_non_local);
                break;

        case DHCP_OPTION_CLASSLESS_STATIC_ROUTE:
                return lease_parse_classless_routes(
                                option, len,
                                &lease->static_route,
                                &lease->static_route_size,
                                &lease->static_route_allocated);

        case DHCP_OPTION_NEW_TZDB_TIMEZONE: {
                _cleanup_free_ char *tz = NULL;

                r = lease_parse_string(option, len, &tz);
                if (r < 0)
                        return r;

                if (!timezone_is_valid(tz))
                        return -EINVAL;

                free(lease->timezone);
                lease->timezone = tz;
                tz = NULL;
                break;
        }

        case DHCP_OPTION_VENDOR_SPECIFIC:

                if (len >= 1) {
                        free(lease->vendor_specific);
                        lease->vendor_specific = memdup(option, len);
                        if (!lease->vendor_specific)
                                return -ENOMEM;
                        lease->vendor_specific_len = len;
                }

               break;

        default:
                if (code < DHCP_OPTION_PRIVATE_BASE || code > DHCP_OPTION_PRIVATE_LAST)
                    break;

                r = dhcp_lease_insert_private_option(lease, code, option, len);
                if (r < 0)
                        return r;
        }

        return 0;
}

int dhcp_lease_insert_private_option(sd_dhcp_lease *lease, uint8_t tag,
                                     const uint8_t *data, uint8_t len) {
        struct sd_dhcp_raw_option *cur, *option;

        LIST_FOREACH(options, cur, lease->private_options) {
                if (tag < cur->tag)
                        break;
                else if (tag == cur->tag) {
                        log_error("Ignoring duplicate option, tagged %d.", tag);
                        return 0;
                }
        }

        option = new(struct sd_dhcp_raw_option, 1);
        if (!option)
                return -ENOMEM;

        option->tag = tag;
        option->length = len;
        option->data = memdup(data, len);
        if (!option->data) {
                free(option);
                return -ENOMEM;
        }

        LIST_INSERT_BEFORE(options, lease->private_options, cur, option);

        return 0;
}

int dhcp_lease_new(sd_dhcp_lease **ret) {
        sd_dhcp_lease *lease;

        lease = new0(sd_dhcp_lease, 1);
        if (!lease)
                return -ENOMEM;

        lease->router = INADDR_ANY;
        lease->n_ref = REFCNT_INIT;
        LIST_HEAD_INIT(lease->private_options);

        *ret = lease;
        return 0;
}

int sd_dhcp_lease_save(sd_dhcp_lease *lease, const char *lease_file) {
        _cleanup_free_ char *temp_path = NULL;
        _cleanup_fclose_ FILE *f = NULL;
        struct sd_dhcp_raw_option *option;
        struct in_addr address;
        const struct in_addr *addresses;
        const uint8_t *client_id, *data;
        size_t client_id_len, data_len;
        const char *string;
        uint16_t mtu;
        struct sd_dhcp_route *routes;
        int r;

        assert(lease);
        assert(lease_file);

        r = fopen_temporary(lease_file, &f, &temp_path);
        if (r < 0)
                goto fail;

        fchmod(fileno(f), 0644);

        r = sd_dhcp_lease_get_address(lease, &address);
        if (r < 0)
                goto fail;

        fprintf(f,
                "# This is private data. Do not parse.\n"
                "ADDRESS=%s\n", inet_ntoa(address));

        r = sd_dhcp_lease_get_netmask(lease, &address);
        if (r < 0)
                goto fail;

        fprintf(f, "NETMASK=%s\n", inet_ntoa(address));

        r = sd_dhcp_lease_get_router(lease, &address);
        if (r >= 0)
                fprintf(f, "ROUTER=%s\n", inet_ntoa(address));

        r = sd_dhcp_lease_get_server_identifier(lease, &address);
        if (r >= 0)
                fprintf(f, "SERVER_ADDRESS=%s\n",
                        inet_ntoa(address));

        r = sd_dhcp_lease_get_next_server(lease, &address);
        if (r >= 0)
                fprintf(f, "NEXT_SERVER=%s\n", inet_ntoa(address));

        r = sd_dhcp_lease_get_mtu(lease, &mtu);
        if (r >= 0)
                fprintf(f, "MTU=%" PRIu16 "\n", mtu);

        fputs("DNS=", f);
        r = sd_dhcp_lease_get_dns(lease, &addresses);
        if (r >= 0)
                serialize_in_addrs(f, addresses, r);
        fputs("\n", f);

        fputs("NTP=", f);
        r = sd_dhcp_lease_get_ntp(lease, &addresses);
        if (r >= 0)
                serialize_in_addrs(f, addresses, r);
        fputs("\n", f);

        r = sd_dhcp_lease_get_domainname(lease, &string);
        if (r >= 0)
                fprintf(f, "DOMAINNAME=%s\n", string);

        r = sd_dhcp_lease_get_hostname(lease, &string);
        if (r >= 0)
                fprintf(f, "HOSTNAME=%s\n", string);

        r = sd_dhcp_lease_get_root_path(lease, &string);
        if (r >= 0)
                fprintf(f, "ROOT_PATH=%s\n", string);

        r = sd_dhcp_lease_get_routes(lease, &routes);
        if (r >= 0)
                serialize_dhcp_routes(f, "ROUTES", routes, r);

        r = sd_dhcp_lease_get_timezone(lease, &string);
        if (r >= 0)
                fprintf(f, "TIMEZONE=%s\n", string);

        r = sd_dhcp_lease_get_client_id(lease, &client_id, &client_id_len);
        if (r >= 0) {
                _cleanup_free_ char *client_id_hex;

                client_id_hex = hexmem(client_id, client_id_len);
                if (!client_id_hex) {
                        r = -ENOMEM;
                        goto fail;
                }
                fprintf(f, "CLIENTID=%s\n", client_id_hex);
        }

        r = sd_dhcp_lease_get_vendor_specific(lease, &data, &data_len);
        if (r >= 0) {
                _cleanup_free_ char *option_hex = NULL;

                option_hex = hexmem(data, data_len);
                if (!option_hex) {
                        r = -ENOMEM;
                        goto fail;
                }
                fprintf(f, "VENDOR_SPECIFIC=%s\n", option_hex);
        }

        LIST_FOREACH(options, option, lease->private_options) {
                char key[strlen("OPTION_000")+1];
                snprintf(key, sizeof(key), "OPTION_%"PRIu8, option->tag);
                r = serialize_dhcp_option(f, key, option->data, option->length);
                if (r < 0)
                        goto fail;
        }

        r = fflush_and_check(f);
        if (r < 0)
                goto fail;

        if (rename(temp_path, lease_file) < 0) {
                r = -errno;
                goto fail;
        }

        return 0;

fail:
        if (temp_path)
                (void) unlink(temp_path);

        return log_error_errno(r, "Failed to save lease data %s: %m", lease_file);
}

int sd_dhcp_lease_load(sd_dhcp_lease **ret, const char *lease_file) {
        _cleanup_dhcp_lease_unref_ sd_dhcp_lease *lease = NULL;
        _cleanup_free_ char *address = NULL, *router = NULL, *netmask = NULL,
                            *server_address = NULL, *next_server = NULL,
                            *dns = NULL, *ntp = NULL, *mtu = NULL,
                            *routes = NULL, *client_id_hex = NULL,
                            *vendor_specific_hex = NULL,
                            *options[DHCP_OPTION_PRIVATE_LAST -
                                     DHCP_OPTION_PRIVATE_BASE + 1] = { NULL };
        struct in_addr addr;
        int r, i;

        assert(lease_file);
        assert(ret);

        r = dhcp_lease_new(&lease);
        if (r < 0)
                return r;

        r = parse_env_file(lease_file, NEWLINE,
                           "ADDRESS", &address,
                           "ROUTER", &router,
                           "NETMASK", &netmask,
                           "SERVER_IDENTIFIER", &server_address,
                           "NEXT_SERVER", &next_server,
                           "DNS", &dns,
                           "NTP", &ntp,
                           "MTU", &mtu,
                           "DOMAINNAME", &lease->domainname,
                           "HOSTNAME", &lease->hostname,
                           "ROOT_PATH", &lease->root_path,
                           "ROUTES", &routes,
                           "CLIENTID", &client_id_hex,
                           "TIMEZONE", &lease->timezone,
                           "VENDOR_SPECIFIC", &vendor_specific_hex,
                           "OPTION_224", &options[0],
                           "OPTION_225", &options[1],
                           "OPTION_226", &options[2],
                           "OPTION_227", &options[3],
                           "OPTION_228", &options[4],
                           "OPTION_229", &options[5],
                           "OPTION_230", &options[6],
                           "OPTION_231", &options[7],
                           "OPTION_232", &options[8],
                           "OPTION_233", &options[9],
                           "OPTION_234", &options[10],
                           "OPTION_235", &options[11],
                           "OPTION_236", &options[12],
                           "OPTION_237", &options[13],
                           "OPTION_238", &options[14],
                           "OPTION_239", &options[15],
                           "OPTION_240", &options[16],
                           "OPTION_241", &options[17],
                           "OPTION_242", &options[18],
                           "OPTION_243", &options[19],
                           "OPTION_244", &options[20],
                           "OPTION_245", &options[21],
                           "OPTION_246", &options[22],
                           "OPTION_247", &options[23],
                           "OPTION_248", &options[24],
                           "OPTION_249", &options[25],
                           "OPTION_250", &options[26],
                           "OPTION_251", &options[27],
                           "OPTION_252", &options[28],
                           "OPTION_253", &options[29],
                           "OPTION_254", &options[30],
                           NULL);
        if (r < 0) {
                if (r == -ENOENT)
                        return 0;

                return log_error_errno(r, "Failed to read %s: %m", lease_file);
        }

        r = inet_pton(AF_INET, address, &addr);
        if (r < 0)
                return r;

        lease->address = addr.s_addr;

        if (router) {
                r = inet_pton(AF_INET, router, &addr);
                if (r < 0)
                        return r;

                lease->router = addr.s_addr;
        }

        r = inet_pton(AF_INET, netmask, &addr);
        if (r < 0)
                return r;

        lease->subnet_mask = addr.s_addr;

        if (server_address) {
                r = inet_pton(AF_INET, server_address, &addr);
                if (r < 0)
                        return r;

                lease->server_address = addr.s_addr;
        }

        if (next_server) {
                r = inet_pton(AF_INET, next_server, &addr);
                if (r < 0)
                        return r;

                lease->next_server = addr.s_addr;
        }

        if (dns) {
                r = deserialize_in_addrs(&lease->dns, dns);
                if (r < 0)
                        return r;

                lease->dns_size = r;
        }

        if (ntp) {
                r = deserialize_in_addrs(&lease->ntp, ntp);
                if (r < 0)
                        return r;

                lease->ntp_size = r;
        }

        if (mtu) {
                uint16_t u;
                if (sscanf(mtu, "%" SCNu16, &u) > 0)
                        lease->mtu = u;
        }

        if (routes) {
                r = deserialize_dhcp_routes(&lease->static_route, &lease->static_route_size,
                                &lease->static_route_allocated, routes);
                if (r < 0)
                    return r;
        }

        if (client_id_hex) {
                r = deserialize_dhcp_option(&lease->client_id, &lease->client_id_len, client_id_hex);
                if (r < 0)
                        return r;
        }

        if (vendor_specific_hex) {
                r = deserialize_dhcp_option(&lease->vendor_specific, &lease->vendor_specific_len, vendor_specific_hex);
                if (r < 0)
                        return r;
        }

        for (i = 0; i <= DHCP_OPTION_PRIVATE_LAST - DHCP_OPTION_PRIVATE_BASE; i++) {
                _cleanup_free_ uint8_t *data = NULL;
                size_t len;

                if (!options[i])
                        continue;

                r = deserialize_dhcp_option(&data, &len, options[i]);
                if (r < 0)
                        return r;

                r = dhcp_lease_insert_private_option(lease, DHCP_OPTION_PRIVATE_BASE + i, data, len);
                if (r < 0)
                        return r;
        }

        *ret = lease;
        lease = NULL;

        return 0;
}

int dhcp_lease_set_default_subnet_mask(sd_dhcp_lease *lease) {
        struct in_addr address;
        struct in_addr mask;
        int r;

        assert(lease);

        address.s_addr = lease->address;

        /* fall back to the default subnet masks based on address class */
        r = in_addr_default_subnet_mask(&address, &mask);
        if (r < 0)
                return r;

        lease->subnet_mask = mask.s_addr;

        return 0;
}

int sd_dhcp_lease_get_client_id(sd_dhcp_lease *lease, const uint8_t **client_id,
                                size_t *client_id_len) {
        assert_return(lease, -EINVAL);
        assert_return(client_id, -EINVAL);
        assert_return(client_id_len, -EINVAL);

        *client_id = lease->client_id;
        *client_id_len = lease->client_id_len;
        return 0;
}

int dhcp_lease_set_client_id(sd_dhcp_lease *lease, const uint8_t *client_id,
                             size_t client_id_len) {
        assert_return(lease, -EINVAL);
        assert_return((!client_id && !client_id_len) ||
                      (client_id && client_id_len), -EINVAL);

        free (lease->client_id);
        lease->client_id = NULL;
        lease->client_id_len = 0;

        if (client_id) {
                lease->client_id = memdup (client_id, client_id_len);
                lease->client_id_len = client_id_len;
        }

        return 0;
}

int sd_dhcp_lease_get_timezone(sd_dhcp_lease *lease, const char **timezone) {
        assert_return(lease, -EINVAL);
        assert_return(timezone, -EINVAL);

        if (!lease->timezone)
                return -ENXIO;

        *timezone = lease->timezone;
        return 0;
}