[thirdparty/systemd.git] / src / libsystemd-network / sd-ndisc-router.c

/* SPDX-License-Identifier: LGPL-2.1-or-later */
/***
  Copyright © 2014 Intel Corporation. All rights reserved.
***/

#include <netinet/icmp6.h>

#include "sd-ndisc.h"

#include "alloc-util.h"
#include "ndisc-internal.h"
#include "ndisc-router-internal.h"
#include "set.h"
#include "string-table.h"
#include "string-util.h"

static sd_ndisc_router* ndisc_router_free(sd_ndisc_router *rt) {
        if (!rt)
                return NULL;

        icmp6_packet_unref(rt->packet);
        set_free(rt->options);
        return mfree(rt);
}

DEFINE_PUBLIC_TRIVIAL_REF_UNREF_FUNC(sd_ndisc_router, sd_ndisc_router, ndisc_router_free);

sd_ndisc_router* ndisc_router_new(ICMP6Packet *packet) {
        sd_ndisc_router *rt;

        assert(packet);

        rt = new(sd_ndisc_router, 1);
        if (!rt)
                return NULL;

        *rt = (sd_ndisc_router) {
                .n_ref = 1,
                .packet = icmp6_packet_ref(packet),
                .iterator = ITERATOR_FIRST,
        };

        return rt;
}

int sd_ndisc_router_set_sender_address(sd_ndisc_router *rt, const struct in6_addr *addr) {
        assert_return(rt, -EINVAL);

        return icmp6_packet_set_sender_address(rt->packet, addr);
}

int sd_ndisc_router_get_sender_address(sd_ndisc_router *rt, struct in6_addr *ret) {
        assert_return(rt, -EINVAL);

        return icmp6_packet_get_sender_address(rt->packet, ret);
}

int sd_ndisc_router_get_timestamp(sd_ndisc_router *rt, clockid_t clock, uint64_t *ret) {
        assert_return(rt, -EINVAL);
        assert_return(ret, -EINVAL);

        return icmp6_packet_get_timestamp(rt->packet, clock, ret);
}

#define DEFINE_GET_TIMESTAMP(name)                                      \
        int sd_ndisc_router_##name##_timestamp(                         \
                        sd_ndisc_router *rt,                            \
                        clockid_t clock,                                \
                        uint64_t *ret) {                                \
                                                                        \
                usec_t s, t;                                            \
                int r;                                                  \
                                                                        \
                assert_return(rt, -EINVAL);                             \
                assert_return(ret, -EINVAL);                            \
                                                                        \
                r = sd_ndisc_router_##name(rt, &s);                     \
                if (r < 0)                                              \
                        return r;                                       \
                                                                        \
                r = sd_ndisc_router_get_timestamp(rt, clock, &t);       \
                if (r < 0)                                              \
                        return r;                                       \
                                                                        \
                *ret = time_span_to_stamp(s, t);                        \
                return 0;                                               \
        }

DEFINE_GET_TIMESTAMP(get_lifetime);
DEFINE_GET_TIMESTAMP(prefix_get_valid_lifetime);
DEFINE_GET_TIMESTAMP(prefix_get_preferred_lifetime);
DEFINE_GET_TIMESTAMP(route_get_lifetime);
DEFINE_GET_TIMESTAMP(rdnss_get_lifetime);
DEFINE_GET_TIMESTAMP(dnssl_get_lifetime);
DEFINE_GET_TIMESTAMP(prefix64_get_lifetime);
DEFINE_GET_TIMESTAMP(encrypted_dns_get_lifetime);

int ndisc_router_parse(sd_ndisc *nd, sd_ndisc_router *rt) {
        const struct nd_router_advert *a;
        int r;

        assert(rt);
        assert(rt->packet);

        if (rt->packet->raw_size < sizeof(struct nd_router_advert))
                return log_ndisc_errno(nd, SYNTHETIC_ERRNO(EBADMSG),
                                       "Too small to be a router advertisement, ignoring.");

        a = (const struct nd_router_advert*) rt->packet->raw_packet;
        assert(a->nd_ra_type == ND_ROUTER_ADVERT);
        assert(a->nd_ra_code == 0);

        rt->hop_limit = a->nd_ra_curhoplimit;
        rt->flags = a->nd_ra_flags_reserved; /* the first 8 bits */
        rt->lifetime_usec = be16_sec_to_usec(a->nd_ra_router_lifetime, /* max_as_infinity = */ false);
        rt->reachable_time_usec = be32_msec_to_usec(a->nd_ra_reachable, /* max_as_infinity = */ false);
        rt->retransmission_time_usec = be32_msec_to_usec(a->nd_ra_retransmit, /* max_as_infinity = */ false);

        /* RFC 4191 section 2.2
         * Prf (Default Router Preference)
         * 2-bit signed integer. Indicates whether to prefer this router over other default routers. If the
         * Router Lifetime is zero, the preference value MUST be set to (00) by the sender and MUST be
         * ignored by the receiver. If the Reserved (10) value is received, the receiver MUST treat the value
         * as if it were (00). */
        rt->preference = (rt->flags >> 3) & 3;
        if (rt->preference == SD_NDISC_PREFERENCE_RESERVED)
                rt->preference = SD_NDISC_PREFERENCE_MEDIUM;

        r = ndisc_parse_options(rt->packet, &rt->options);
        if (r < 0)
                return log_ndisc_errno(nd, r, "Failed to parse NDisc options in router advertisement message, ignoring: %m");

        return 0;
}

int sd_ndisc_router_get_hop_limit(sd_ndisc_router *rt, uint8_t *ret) {
        assert_return(rt, -EINVAL);
        assert_return(ret, -EINVAL);

        *ret = rt->hop_limit;
        return 0;
}

int sd_ndisc_router_get_reachable_time(sd_ndisc_router *rt, uint64_t *ret) {
        assert_return(rt, -EINVAL);
        assert_return(ret, -EINVAL);

        *ret = rt->reachable_time_usec;
        return 0;
}

int sd_ndisc_router_get_retransmission_time(sd_ndisc_router *rt, uint64_t *ret) {
        assert_return(rt, -EINVAL);
        assert_return(ret, -EINVAL);

        *ret = rt->retransmission_time_usec;
        return 0;
}

int sd_ndisc_router_get_flags(sd_ndisc_router *rt, uint64_t *ret) {
        assert_return(rt, -EINVAL);
        assert_return(ret, -EINVAL);

        sd_ndisc_option *p = ndisc_option_get_by_type(rt->options, SD_NDISC_OPTION_FLAGS_EXTENSION);

        *ret = rt->flags | (p ? p->extended_flags : 0);
        return 0;
}

int ndisc_router_flags_to_string(uint64_t flags, char **ret) {
        _cleanup_free_ char *s = NULL;

        assert(ret);

        if (FLAGS_SET(flags, ND_RA_FLAG_MANAGED) &&
            !strextend_with_separator(&s, ", ", "managed"))
                return -ENOMEM;

        if (FLAGS_SET(flags, ND_RA_FLAG_OTHER) &&
            !strextend_with_separator(&s, ", ", "other"))
                return -ENOMEM;

        if (FLAGS_SET(flags, ND_RA_FLAG_HOME_AGENT) &&
            !strextend_with_separator(&s, ", ", "home-agent"))
                return -ENOMEM;

        *ret = TAKE_PTR(s);
        return 0;
}

int sd_ndisc_router_get_lifetime(sd_ndisc_router *rt, uint64_t *ret) {
        assert_return(rt, -EINVAL);

        if (ret)
                *ret = rt->lifetime_usec;

        return rt->lifetime_usec > 0; /* Indicate if the router is still valid or not. */
}

int sd_ndisc_router_get_preference(sd_ndisc_router *rt, uint8_t *ret) {
        assert_return(rt, -EINVAL);
        assert_return(ret, -EINVAL);

        *ret = rt->preference;
        return 0;
}

static const char* const ndisc_router_preference_table[] = {
        [SD_NDISC_PREFERENCE_LOW]      = "low",
        [SD_NDISC_PREFERENCE_MEDIUM]   = "medium",
        [SD_NDISC_PREFERENCE_HIGH]     = "high",
        [SD_NDISC_PREFERENCE_RESERVED] = "reserved",
};

DEFINE_STRING_TABLE_LOOKUP_TO_STRING(ndisc_router_preference, int);

int sd_ndisc_router_get_sender_mac(sd_ndisc_router *rt, struct ether_addr *ret) {
        assert_return(rt, -EINVAL);

        return ndisc_option_get_mac(rt->options, SD_NDISC_OPTION_SOURCE_LL_ADDRESS, ret);
}

int sd_ndisc_router_get_mtu(sd_ndisc_router *rt, uint32_t *ret) {
        assert_return(rt, -EINVAL);
        assert_return(ret, -EINVAL);

        sd_ndisc_option *p = ndisc_option_get_by_type(rt->options, SD_NDISC_OPTION_MTU);
        if (!p)
                return -ENODATA;

        *ret = p->mtu;
        return 0;
}

int sd_ndisc_router_get_captive_portal(sd_ndisc_router *rt, const char **ret) {
        assert_return(rt, -EINVAL);
        assert_return(ret, -EINVAL);

        sd_ndisc_option *p = ndisc_option_get_by_type(rt->options, SD_NDISC_OPTION_CAPTIVE_PORTAL);
        if (!p)
                return -ENODATA;

        *ret = p->captive_portal;
        return 0;
}

int sd_ndisc_router_option_rewind(sd_ndisc_router *rt) {
        assert_return(rt, -EINVAL);

        rt->iterator = ITERATOR_FIRST;
        return sd_ndisc_router_option_next(rt);
}

int sd_ndisc_router_option_next(sd_ndisc_router *rt) {
        assert_return(rt, -EINVAL);

        return set_iterate(rt->options, &rt->iterator, (void**) &rt->current_option);
}

int sd_ndisc_router_option_get_type(sd_ndisc_router *rt, uint8_t *ret) {
        assert_return(rt, -EINVAL);
        assert_return(ret, -EINVAL);

        if (!rt->current_option)
                return -ENODATA;

        *ret = rt->current_option->type;
        return 0;
}

int sd_ndisc_router_option_is_type(sd_ndisc_router *rt, uint8_t type) {
        uint8_t t;
        int r;

        assert_return(rt, -EINVAL);

        r = sd_ndisc_router_option_get_type(rt, &t);
        if (r < 0)
                return r;

        return t == type;
}

int sd_ndisc_router_option_get_raw(sd_ndisc_router *rt, const uint8_t **ret, size_t *ret_size) {
        assert_return(rt, -EINVAL);

        if (!rt->current_option)
                return -ENODATA;

        return ndisc_option_parse(rt->packet, rt->current_option->offset, NULL, ret_size, ret);
}

#define DEFINE_GETTER(name, type, element, element_type)                \
        int sd_ndisc_router_##name##_get_##element(                     \
                        sd_ndisc_router *rt,                            \
                        element_type *ret) {                            \
                                                                        \
                int r;                                                  \
                                                                        \
                assert_return(rt, -EINVAL);                             \
                assert_return(ret, -EINVAL);                            \
                                                                        \
                r = sd_ndisc_router_option_is_type(rt, type);           \
                if (r < 0)                                              \
                        return r;                                       \
                if (r == 0)                                             \
                        return -EMEDIUMTYPE;                            \
                                                                        \
                *ret = rt->current_option->name.element;                \
                return 0;                                               \
        }

DEFINE_GETTER(prefix, SD_NDISC_OPTION_PREFIX_INFORMATION, flags, uint8_t);
DEFINE_GETTER(prefix, SD_NDISC_OPTION_PREFIX_INFORMATION, prefixlen, uint8_t);
DEFINE_GETTER(prefix, SD_NDISC_OPTION_PREFIX_INFORMATION, address, struct in6_addr);
DEFINE_GETTER(prefix, SD_NDISC_OPTION_PREFIX_INFORMATION, valid_lifetime, uint64_t);
DEFINE_GETTER(prefix, SD_NDISC_OPTION_PREFIX_INFORMATION, preferred_lifetime, uint64_t);

DEFINE_GETTER(route, SD_NDISC_OPTION_ROUTE_INFORMATION, preference, uint8_t);
DEFINE_GETTER(route, SD_NDISC_OPTION_ROUTE_INFORMATION, prefixlen, uint8_t);
DEFINE_GETTER(route, SD_NDISC_OPTION_ROUTE_INFORMATION, address, struct in6_addr);
DEFINE_GETTER(route, SD_NDISC_OPTION_ROUTE_INFORMATION, lifetime, uint64_t);

DEFINE_GETTER(rdnss, SD_NDISC_OPTION_RDNSS, lifetime, uint64_t);

int sd_ndisc_router_rdnss_get_addresses(sd_ndisc_router *rt, const struct in6_addr **ret) {
        int r;

        assert_return(rt, -EINVAL);
        assert_return(ret, -EINVAL);

        r = sd_ndisc_router_option_is_type(rt, SD_NDISC_OPTION_RDNSS);
        if (r < 0)
                return r;
        if (r == 0)
                return -EMEDIUMTYPE;

        *ret = rt->current_option->rdnss.addresses;
        return (int) rt->current_option->rdnss.n_addresses;
}

DEFINE_GETTER(dnssl, SD_NDISC_OPTION_DNSSL, domains, char**);
DEFINE_GETTER(dnssl, SD_NDISC_OPTION_DNSSL, lifetime, uint64_t);

DEFINE_GETTER(prefix64, SD_NDISC_OPTION_PREF64, prefixlen, uint8_t);
DEFINE_GETTER(prefix64, SD_NDISC_OPTION_PREF64, prefix, struct in6_addr);
DEFINE_GETTER(prefix64, SD_NDISC_OPTION_PREF64, lifetime, uint64_t);

DEFINE_GETTER(encrypted_dns, SD_NDISC_OPTION_ENCRYPTED_DNS, lifetime, uint64_t);
DEFINE_GETTER(encrypted_dns, SD_NDISC_OPTION_ENCRYPTED_DNS, resolver, sd_dns_resolver*);
Commit	Line	Data
	1	/* SPDX-License-Identifier: LGPL-2.1-or-later */
	2	/***
	3	Copyright © 2014 Intel Corporation. All rights reserved.
	4	***/
	5
	6	#include <netinet/icmp6.h>
	7
	8	#include "sd-ndisc.h"
	9
	10	#include "alloc-util.h"
	11	#include "ndisc-internal.h"
	12	#include "ndisc-router-internal.h"
	13	#include "set.h"
	14	#include "string-table.h"
	15	#include "string-util.h"
	16
	17	static sd_ndisc_router* ndisc_router_free(sd_ndisc_router *rt) {
	18	if (!rt)
	19	return NULL;
	20
	21	icmp6_packet_unref(rt->packet);
	22	set_free(rt->options);
	23	return mfree(rt);
	24	}
	25
	26	DEFINE_PUBLIC_TRIVIAL_REF_UNREF_FUNC(sd_ndisc_router, sd_ndisc_router, ndisc_router_free);
	27
	28	sd_ndisc_router* ndisc_router_new(ICMP6Packet *packet) {
	29	sd_ndisc_router *rt;
	30
	31	assert(packet);
	32
	33	rt = new(sd_ndisc_router, 1);
	34	if (!rt)
	35	return NULL;
	36
	37	*rt = (sd_ndisc_router) {
	38	.n_ref = 1,
	39	.packet = icmp6_packet_ref(packet),
	40	.iterator = ITERATOR_FIRST,
	41	};
	42
	43	return rt;
	44	}
	45
	46	int sd_ndisc_router_set_sender_address(sd_ndisc_router rt, const struct in6_addr addr) {
	47	assert_return(rt, -EINVAL);
	48
	49	return icmp6_packet_set_sender_address(rt->packet, addr);
	50	}
	51
	52	int sd_ndisc_router_get_sender_address(sd_ndisc_router rt, struct in6_addr ret) {
	53	assert_return(rt, -EINVAL);
	54
	55	return icmp6_packet_get_sender_address(rt->packet, ret);
	56	}
	57
	58	int sd_ndisc_router_get_timestamp(sd_ndisc_router rt, clockid_t clock, uint64_t ret) {
	59	assert_return(rt, -EINVAL);
	60	assert_return(ret, -EINVAL);
	61
	62	return icmp6_packet_get_timestamp(rt->packet, clock, ret);
	63	}
	64
	65	#define DEFINE_GET_TIMESTAMP(name) \
	66	int sd_ndisc_router_##name##_timestamp( \
	67	sd_ndisc_router *rt, \
	68	clockid_t clock, \
	69	uint64_t *ret) { \
	70	\
	71	usec_t s, t; \
	72	int r; \
	73	\
	74	assert_return(rt, -EINVAL); \
	75	assert_return(ret, -EINVAL); \
	76	\
	77	r = sd_ndisc_router_##name(rt, &s); \
	78	if (r < 0) \
	79	return r; \
	80	\
	81	r = sd_ndisc_router_get_timestamp(rt, clock, &t); \
	82	if (r < 0) \
	83	return r; \
	84	\
	85	*ret = time_span_to_stamp(s, t); \
	86	return 0; \
	87	}
	88
	89	DEFINE_GET_TIMESTAMP(get_lifetime);
	90	DEFINE_GET_TIMESTAMP(prefix_get_valid_lifetime);
	91	DEFINE_GET_TIMESTAMP(prefix_get_preferred_lifetime);
	92	DEFINE_GET_TIMESTAMP(route_get_lifetime);
	93	DEFINE_GET_TIMESTAMP(rdnss_get_lifetime);
	94	DEFINE_GET_TIMESTAMP(dnssl_get_lifetime);
	95	DEFINE_GET_TIMESTAMP(prefix64_get_lifetime);
	96	DEFINE_GET_TIMESTAMP(encrypted_dns_get_lifetime);
	97
	98	int ndisc_router_parse(sd_ndisc nd, sd_ndisc_router rt) {
	99	const struct nd_router_advert *a;
	100	int r;
	101
	102	assert(rt);
	103	assert(rt->packet);
	104
	105	if (rt->packet->raw_size < sizeof(struct nd_router_advert))
	106	return log_ndisc_errno(nd, SYNTHETIC_ERRNO(EBADMSG),
	107	"Too small to be a router advertisement, ignoring.");
	108
	109	a = (const struct nd_router_advert*) rt->packet->raw_packet;
	110	assert(a->nd_ra_type == ND_ROUTER_ADVERT);
	111	assert(a->nd_ra_code == 0);
	112
	113	rt->hop_limit = a->nd_ra_curhoplimit;
	114	rt->flags = a->nd_ra_flags_reserved; /* the first 8 bits */
	115	rt->lifetime_usec = be16_sec_to_usec(a->nd_ra_router_lifetime, /* max_as_infinity = */ false);
	116	rt->reachable_time_usec = be32_msec_to_usec(a->nd_ra_reachable, /* max_as_infinity = */ false);
	117	rt->retransmission_time_usec = be32_msec_to_usec(a->nd_ra_retransmit, /* max_as_infinity = */ false);
	118
	119	/* RFC 4191 section 2.2
	120	* Prf (Default Router Preference)
	121	* 2-bit signed integer. Indicates whether to prefer this router over other default routers. If the
	122	* Router Lifetime is zero, the preference value MUST be set to (00) by the sender and MUST be
	123	* ignored by the receiver. If the Reserved (10) value is received, the receiver MUST treat the value
	124	* as if it were (00). */
	125	rt->preference = (rt->flags >> 3) & 3;
	126	if (rt->preference == SD_NDISC_PREFERENCE_RESERVED)
	127	rt->preference = SD_NDISC_PREFERENCE_MEDIUM;
	128
	129	r = ndisc_parse_options(rt->packet, &rt->options);
	130	if (r < 0)
	131	return log_ndisc_errno(nd, r, "Failed to parse NDisc options in router advertisement message, ignoring: %m");
	132
	133	return 0;
	134	}
	135
	136	int sd_ndisc_router_get_hop_limit(sd_ndisc_router rt, uint8_t ret) {
	137	assert_return(rt, -EINVAL);
	138	assert_return(ret, -EINVAL);
	139
	140	*ret = rt->hop_limit;
	141	return 0;
	142	}
	143
	144	int sd_ndisc_router_get_reachable_time(sd_ndisc_router rt, uint64_t ret) {
	145	assert_return(rt, -EINVAL);
	146	assert_return(ret, -EINVAL);
	147
	148	*ret = rt->reachable_time_usec;
	149	return 0;
	150	}
	151
	152	int sd_ndisc_router_get_retransmission_time(sd_ndisc_router rt, uint64_t ret) {
	153	assert_return(rt, -EINVAL);
	154	assert_return(ret, -EINVAL);
	155
	156	*ret = rt->retransmission_time_usec;
	157	return 0;
	158	}
	159
	160	int sd_ndisc_router_get_flags(sd_ndisc_router rt, uint64_t ret) {
	161	assert_return(rt, -EINVAL);
	162	assert_return(ret, -EINVAL);
	163
	164	sd_ndisc_option *p = ndisc_option_get_by_type(rt->options, SD_NDISC_OPTION_FLAGS_EXTENSION);
	165
	166	*ret = rt->flags \| (p ? p->extended_flags : 0);
	167	return 0;
	168	}
	169
	170	int ndisc_router_flags_to_string(uint64_t flags, char **ret) {
	171	_cleanup_free_ char *s = NULL;
	172
	173	assert(ret);
	174
	175	if (FLAGS_SET(flags, ND_RA_FLAG_MANAGED) &&
	176	!strextend_with_separator(&s, ", ", "managed"))
	177	return -ENOMEM;
	178
	179	if (FLAGS_SET(flags, ND_RA_FLAG_OTHER) &&
	180	!strextend_with_separator(&s, ", ", "other"))
	181	return -ENOMEM;
	182
	183	if (FLAGS_SET(flags, ND_RA_FLAG_HOME_AGENT) &&
	184	!strextend_with_separator(&s, ", ", "home-agent"))
	185	return -ENOMEM;
	186
	187	*ret = TAKE_PTR(s);
	188	return 0;
	189	}
	190
	191	int sd_ndisc_router_get_lifetime(sd_ndisc_router rt, uint64_t ret) {
	192	assert_return(rt, -EINVAL);
	193
	194	if (ret)
	195	*ret = rt->lifetime_usec;
	196
	197	return rt->lifetime_usec > 0; /* Indicate if the router is still valid or not. */
	198	}
	199
	200	int sd_ndisc_router_get_preference(sd_ndisc_router rt, uint8_t ret) {
	201	assert_return(rt, -EINVAL);
	202	assert_return(ret, -EINVAL);
	203
	204	*ret = rt->preference;
	205	return 0;
	206	}
	207
	208	static const char* const ndisc_router_preference_table[] = {
	209	[SD_NDISC_PREFERENCE_LOW] = "low",
	210	[SD_NDISC_PREFERENCE_MEDIUM] = "medium",
	211	[SD_NDISC_PREFERENCE_HIGH] = "high",
	212	[SD_NDISC_PREFERENCE_RESERVED] = "reserved",
	213	};
	214
	215	DEFINE_STRING_TABLE_LOOKUP_TO_STRING(ndisc_router_preference, int);
	216
	217	int sd_ndisc_router_get_sender_mac(sd_ndisc_router rt, struct ether_addr ret) {
	218	assert_return(rt, -EINVAL);
	219
	220	return ndisc_option_get_mac(rt->options, SD_NDISC_OPTION_SOURCE_LL_ADDRESS, ret);
	221	}
	222
	223	int sd_ndisc_router_get_mtu(sd_ndisc_router rt, uint32_t ret) {
	224	assert_return(rt, -EINVAL);
	225	assert_return(ret, -EINVAL);
	226
	227	sd_ndisc_option *p = ndisc_option_get_by_type(rt->options, SD_NDISC_OPTION_MTU);
	228	if (!p)
	229	return -ENODATA;
	230
	231	*ret = p->mtu;
	232	return 0;
	233	}
	234
	235	int sd_ndisc_router_get_captive_portal(sd_ndisc_router rt, const char *ret) {
	236	assert_return(rt, -EINVAL);
	237	assert_return(ret, -EINVAL);
	238
	239	sd_ndisc_option *p = ndisc_option_get_by_type(rt->options, SD_NDISC_OPTION_CAPTIVE_PORTAL);
	240	if (!p)
	241	return -ENODATA;
	242
	243	*ret = p->captive_portal;
	244	return 0;
	245	}
	246
	247	int sd_ndisc_router_option_rewind(sd_ndisc_router *rt) {
	248	assert_return(rt, -EINVAL);
	249
	250	rt->iterator = ITERATOR_FIRST;
	251	return sd_ndisc_router_option_next(rt);
	252	}
	253
	254	int sd_ndisc_router_option_next(sd_ndisc_router *rt) {
	255	assert_return(rt, -EINVAL);
	256
	257	return set_iterate(rt->options, &rt->iterator, (void**) &rt->current_option);
	258	}
	259
	260	int sd_ndisc_router_option_get_type(sd_ndisc_router rt, uint8_t ret) {
	261	assert_return(rt, -EINVAL);
	262	assert_return(ret, -EINVAL);
	263
	264	if (!rt->current_option)
	265	return -ENODATA;
	266
	267	*ret = rt->current_option->type;
	268	return 0;
	269	}
	270
	271	int sd_ndisc_router_option_is_type(sd_ndisc_router *rt, uint8_t type) {
	272	uint8_t t;
	273	int r;
	274
	275	assert_return(rt, -EINVAL);
	276
	277	r = sd_ndisc_router_option_get_type(rt, &t);
	278	if (r < 0)
	279	return r;
	280
	281	return t == type;
	282	}
	283
	284	int sd_ndisc_router_option_get_raw(sd_ndisc_router rt, const uint8_t ret, size_t ret_size) {
	285	assert_return(rt, -EINVAL);
	286
	287	if (!rt->current_option)
	288	return -ENODATA;
	289
	290	return ndisc_option_parse(rt->packet, rt->current_option->offset, NULL, ret_size, ret);
	291	}
	292
	293	#define DEFINE_GETTER(name, type, element, element_type) \
	294	int sd_ndisc_router_##name##_get_##element( \
	295	sd_ndisc_router *rt, \
	296	element_type *ret) { \
	297	\
	298	int r; \
	299	\
	300	assert_return(rt, -EINVAL); \
	301	assert_return(ret, -EINVAL); \
	302	\
	303	r = sd_ndisc_router_option_is_type(rt, type); \
	304	if (r < 0) \
	305	return r; \
	306	if (r == 0) \
	307	return -EMEDIUMTYPE; \
	308	\
	309	*ret = rt->current_option->name.element; \
	310	return 0; \
	311	}
	312
	313	DEFINE_GETTER(prefix, SD_NDISC_OPTION_PREFIX_INFORMATION, flags, uint8_t);
	314	DEFINE_GETTER(prefix, SD_NDISC_OPTION_PREFIX_INFORMATION, prefixlen, uint8_t);
	315	DEFINE_GETTER(prefix, SD_NDISC_OPTION_PREFIX_INFORMATION, address, struct in6_addr);
	316	DEFINE_GETTER(prefix, SD_NDISC_OPTION_PREFIX_INFORMATION, valid_lifetime, uint64_t);
	317	DEFINE_GETTER(prefix, SD_NDISC_OPTION_PREFIX_INFORMATION, preferred_lifetime, uint64_t);
	318
	319	DEFINE_GETTER(route, SD_NDISC_OPTION_ROUTE_INFORMATION, preference, uint8_t);
	320	DEFINE_GETTER(route, SD_NDISC_OPTION_ROUTE_INFORMATION, prefixlen, uint8_t);
	321	DEFINE_GETTER(route, SD_NDISC_OPTION_ROUTE_INFORMATION, address, struct in6_addr);
	322	DEFINE_GETTER(route, SD_NDISC_OPTION_ROUTE_INFORMATION, lifetime, uint64_t);
	323
	324	DEFINE_GETTER(rdnss, SD_NDISC_OPTION_RDNSS, lifetime, uint64_t);
	325
	326	int sd_ndisc_router_rdnss_get_addresses(sd_ndisc_router rt, const struct in6_addr *ret) {
	327	int r;
	328
	329	assert_return(rt, -EINVAL);
	330	assert_return(ret, -EINVAL);
	331
	332	r = sd_ndisc_router_option_is_type(rt, SD_NDISC_OPTION_RDNSS);
	333	if (r < 0)
	334	return r;
	335	if (r == 0)
	336	return -EMEDIUMTYPE;
	337
	338	*ret = rt->current_option->rdnss.addresses;
	339	return (int) rt->current_option->rdnss.n_addresses;
	340	}
	341
	342	DEFINE_GETTER(dnssl, SD_NDISC_OPTION_DNSSL, domains, char**);
	343	DEFINE_GETTER(dnssl, SD_NDISC_OPTION_DNSSL, lifetime, uint64_t);
	344
	345	DEFINE_GETTER(prefix64, SD_NDISC_OPTION_PREF64, prefixlen, uint8_t);
	346	DEFINE_GETTER(prefix64, SD_NDISC_OPTION_PREF64, prefix, struct in6_addr);
	347	DEFINE_GETTER(prefix64, SD_NDISC_OPTION_PREF64, lifetime, uint64_t);
	348
	349	DEFINE_GETTER(encrypted_dns, SD_NDISC_OPTION_ENCRYPTED_DNS, lifetime, uint64_t);
	350	DEFINE_GETTER(encrypted_dns, SD_NDISC_OPTION_ENCRYPTED_DNS, resolver, sd_dns_resolver*);