[thirdparty/systemd.git] / src / libsystemd-network / sd-icmp6-nd.c

/***
  This file is part of systemd.

  Copyright (C) 2014 Intel Corporation. All rights reserved.

  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 <netinet/icmp6.h>
#include <netinet/ip6.h>
#include <string.h>
#include <stdbool.h>
#include <netinet/in.h>
#include <sys/ioctl.h>

#include "socket-util.h"
#include "refcnt.h"
#include "async.h"

#include "dhcp6-internal.h"
#include "sd-icmp6-nd.h"

#define ICMP6_ROUTER_SOLICITATION_INTERVAL      4 * USEC_PER_SEC
#define ICMP6_MAX_ROUTER_SOLICITATIONS          3

enum icmp6_nd_state {
        ICMP6_NEIGHBOR_DISCOVERY_IDLE           = 0,
        ICMP6_ROUTER_SOLICITATION_SENT          = 10,
        ICMP6_ROUTER_ADVERTISMENT_LISTEN        = 11,
};

#define IP6_MIN_MTU (unsigned)1280
#define ICMP6_ND_RECV_SIZE (IP6_MIN_MTU - sizeof(struct ip6_hdr))
#define ICMP6_OPT_LEN_UNITS 8

typedef struct ICMP6Prefix ICMP6Prefix;

struct ICMP6Prefix {
        RefCount n_ref;

        LIST_FIELDS(ICMP6Prefix, prefixes);

        uint8_t len;
        sd_event_source *timeout_valid;
        struct in6_addr addr;
};

struct sd_icmp6_nd {
        RefCount n_ref;

        enum icmp6_nd_state state;
        sd_event *event;
        int event_priority;
        int index;
        struct ether_addr mac_addr;
        uint32_t mtu;
        LIST_HEAD(ICMP6Prefix, prefixes);
        int fd;
        sd_event_source *recv;
        sd_event_source *timeout;
        int nd_sent;
        sd_icmp6_nd_callback_t callback;
        void *userdata;
};

#define log_icmp6_nd(p, fmt, ...) log_internal(LOG_DEBUG, 0, __FILE__, __LINE__, __func__, "ICMPv6 CLIENT: " fmt, ##__VA_ARGS__)

static ICMP6Prefix *icmp6_prefix_unref(ICMP6Prefix *prefix) {
        if (prefix && REFCNT_DEC(prefix->n_ref) <= 0) {
                prefix->timeout_valid =
                        sd_event_source_unref(prefix->timeout_valid);

                free(prefix);
        }

        return NULL;
}

static int icmp6_prefix_new(ICMP6Prefix **ret) {
        _cleanup_free_ ICMP6Prefix *prefix = NULL;

        assert(ret);

        prefix = new0(ICMP6Prefix, 1);
        if (!prefix)
                return -ENOMEM;

        prefix->n_ref = REFCNT_INIT;
        LIST_INIT(prefixes, prefix);

        *ret = prefix;
        prefix = NULL;

        return 0;
}

static void icmp6_nd_notify(sd_icmp6_nd *nd, int event)
{
        if (nd->callback)
                nd->callback(nd, event, nd->userdata);
}

int sd_icmp6_nd_set_callback(sd_icmp6_nd *nd, sd_icmp6_nd_callback_t callback,
                             void *userdata) {
        assert(nd);

        nd->callback = callback;
        nd->userdata = userdata;

        return 0;
}

int sd_icmp6_nd_set_index(sd_icmp6_nd *nd, int interface_index) {
        assert(nd);
        assert(interface_index >= -1);

        nd->index = interface_index;

        return 0;
}

int sd_icmp6_nd_set_mac(sd_icmp6_nd *nd, const struct ether_addr *mac_addr) {
        assert(nd);

        if (mac_addr)
                memcpy(&nd->mac_addr, mac_addr, sizeof(nd->mac_addr));
        else
                zero(nd->mac_addr);

        return 0;

}

int sd_icmp6_nd_attach_event(sd_icmp6_nd *nd, sd_event *event, int priority) {
        int r;

        assert_return(nd, -EINVAL);
        assert_return(!nd->event, -EBUSY);

        if (event)
                nd->event = sd_event_ref(event);
        else {
                r = sd_event_default(&nd->event);
                if (r < 0)
                        return 0;
        }

        nd->event_priority = priority;

        return 0;
}

int sd_icmp6_nd_detach_event(sd_icmp6_nd *nd) {
        assert_return(nd, -EINVAL);

        nd->event = sd_event_unref(nd->event);

        return 0;
}

sd_event *sd_icmp6_nd_get_event(sd_icmp6_nd *nd) {
        assert(nd);

        return nd->event;
}

sd_icmp6_nd *sd_icmp6_nd_ref(sd_icmp6_nd *nd) {
        assert (nd);

        assert_se(REFCNT_INC(nd->n_ref) >= 2);

        return nd;
}

static int icmp6_nd_init(sd_icmp6_nd *nd) {
        assert(nd);

        nd->recv = sd_event_source_unref(nd->recv);
        nd->fd = asynchronous_close(nd->fd);
        nd->timeout = sd_event_source_unref(nd->timeout);

        return 0;
}

sd_icmp6_nd *sd_icmp6_nd_unref(sd_icmp6_nd *nd) {
        if (nd && REFCNT_DEC(nd->n_ref) == 0) {
                ICMP6Prefix *prefix, *p;

                icmp6_nd_init(nd);
                sd_icmp6_nd_detach_event(nd);

                LIST_FOREACH_SAFE(prefixes, prefix, p, nd->prefixes) {
                        LIST_REMOVE(prefixes, nd->prefixes, prefix);

                        prefix = icmp6_prefix_unref(prefix);
                }

                free(nd);
        }

        return NULL;
}

DEFINE_TRIVIAL_CLEANUP_FUNC(sd_icmp6_nd*, sd_icmp6_nd_unref);
#define _cleanup_sd_icmp6_nd_free_ _cleanup_(sd_icmp6_nd_unrefp)

int sd_icmp6_nd_new(sd_icmp6_nd **ret) {
        _cleanup_sd_icmp6_nd_free_ sd_icmp6_nd *nd = NULL;

        assert(ret);

        nd = new0(sd_icmp6_nd, 1);
        if (!nd)
                return -ENOMEM;

        nd->n_ref = REFCNT_INIT;

        nd->index = -1;
        nd->fd = -1;

        LIST_HEAD_INIT(nd->prefixes);

        *ret = nd;
        nd = NULL;

        return 0;
}

int sd_icmp6_ra_get_mtu(sd_icmp6_nd *nd, uint32_t *mtu) {
        assert_return(nd, -EINVAL);
        assert_return(mtu, -EINVAL);

        if (nd->mtu == 0)
                return -ENOMSG;

        *mtu = nd->mtu;

        return 0;
}

static int icmp6_ra_parse(sd_icmp6_nd *nd, struct nd_router_advert *ra,
                          ssize_t len) {
        void *opt;
        struct nd_opt_hdr *opt_hdr;

        assert_return(nd, -EINVAL);
        assert_return(ra, -EINVAL);

        len -= sizeof(*ra);
        if (len < ICMP6_OPT_LEN_UNITS) {
                log_icmp6_nd(nd, "Router Advertisement below minimum length");

                return -ENOMSG;
        }

        opt = ra + 1;
        opt_hdr = opt;

        while (len != 0 && len >= opt_hdr->nd_opt_len * ICMP6_OPT_LEN_UNITS) {
                struct nd_opt_mtu *opt_mtu;
                uint32_t mtu;

                if (opt_hdr->nd_opt_len == 0)
                        return -ENOMSG;

                switch (opt_hdr->nd_opt_type) {
                case ND_OPT_MTU:
                        opt_mtu = opt;

                        mtu = be32toh(opt_mtu->nd_opt_mtu_mtu);

                        if (mtu != nd->mtu) {
                                nd->mtu = MAX(mtu, IP6_MIN_MTU);

                                log_icmp6_nd(nd, "Router Advertisement link MTU %d using %d",
                                             mtu, nd->mtu);
                        }

                        break;

                }

                len -= opt_hdr->nd_opt_len * ICMP6_OPT_LEN_UNITS;
                opt = (void *)((char *)opt +
                        opt_hdr->nd_opt_len * ICMP6_OPT_LEN_UNITS);
                opt_hdr = opt;
        }

        if (len > 0)
                log_icmp6_nd(nd, "Router Advertisement contains %zd bytes of trailing garbage", len);

        return 0;
}

static int icmp6_router_advertisment_recv(sd_event_source *s, int fd,
                                          uint32_t revents, void *userdata)
{
        sd_icmp6_nd *nd = userdata;
        int r, buflen = 0;
        ssize_t len;
        _cleanup_free_ struct nd_router_advert *ra = NULL;
        int event = ICMP6_EVENT_ROUTER_ADVERTISMENT_NONE;

        assert(s);
        assert(nd);
        assert(nd->event);

        r = ioctl(fd, FIONREAD, &buflen);
        if (r < 0 || buflen <= 0)
                buflen = ICMP6_ND_RECV_SIZE;

        ra = malloc(buflen);
        if (!ra)
                return -ENOMEM;

        len = read(fd, ra, buflen);
        if (len < 0) {
                log_icmp6_nd(nd, "Could not receive message from UDP socket: %m");
                return 0;
        }

        if (ra->nd_ra_type != ND_ROUTER_ADVERT)
                return 0;

        if (ra->nd_ra_code != 0)
                return 0;

        nd->timeout = sd_event_source_unref(nd->timeout);

        nd->state = ICMP6_ROUTER_ADVERTISMENT_LISTEN;

        if (ra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER )
                event = ICMP6_EVENT_ROUTER_ADVERTISMENT_OTHER;

        if (ra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED)
                event = ICMP6_EVENT_ROUTER_ADVERTISMENT_MANAGED;

        log_icmp6_nd(nd, "Received Router Advertisement flags %s/%s",
                     ra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED? "MANAGED": "none",
                     ra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER? "OTHER": "none");

        if (event != ICMP6_EVENT_ROUTER_ADVERTISMENT_NONE) {
                r = icmp6_ra_parse(nd, ra, len);
                if (r < 0) {
                        log_icmp6_nd(nd, "Could not parse Router Advertisement: %s",
                                     strerror(-r));
                        return 0;
                }
        }

        icmp6_nd_notify(nd, event);

        return 0;
}

static int icmp6_router_solicitation_timeout(sd_event_source *s, uint64_t usec,
                                             void *userdata)
{
        sd_icmp6_nd *nd = userdata;
        uint64_t time_now, next_timeout;
        struct ether_addr unset = { };
        struct ether_addr *addr = NULL;
        int r;

        assert(s);
        assert(nd);
        assert(nd->event);

        nd->timeout = sd_event_source_unref(nd->timeout);

        if (nd->nd_sent >= ICMP6_MAX_ROUTER_SOLICITATIONS) {
                icmp6_nd_notify(nd, ICMP6_EVENT_ROUTER_ADVERTISMENT_TIMEOUT);
                nd->state = ICMP6_ROUTER_ADVERTISMENT_LISTEN;
        } else {
                if (memcmp(&nd->mac_addr, &unset, sizeof(struct ether_addr)))
                        addr = &nd->mac_addr;

                r = dhcp_network_icmp6_send_router_solicitation(nd->fd, addr);
                if (r < 0)
                        log_icmp6_nd(nd, "Error sending Router Solicitation");
                else {
                        nd->state = ICMP6_ROUTER_SOLICITATION_SENT;
                        log_icmp6_nd(nd, "Sent Router Solicitation");
                }

                nd->nd_sent++;

                r = sd_event_now(nd->event, clock_boottime_or_monotonic(), &time_now);
                if (r < 0) {
                        icmp6_nd_notify(nd, r);
                        return 0;
                }

                next_timeout = time_now + ICMP6_ROUTER_SOLICITATION_INTERVAL;

                r = sd_event_add_time(nd->event, &nd->timeout, clock_boottime_or_monotonic(),
                                      next_timeout, 0,
                                      icmp6_router_solicitation_timeout, nd);
                if (r < 0) {
                        icmp6_nd_notify(nd, r);
                        return 0;
                }

                r = sd_event_source_set_priority(nd->timeout,
                                                 nd->event_priority);
                if (r < 0) {
                        icmp6_nd_notify(nd, r);
                        return 0;
                }

                r = sd_event_source_set_description(nd->timeout, "icmp6-timeout");
                if (r < 0) {
                        icmp6_nd_notify(nd, r);
                        return 0;
                }
        }

        return 0;
}

int sd_icmp6_nd_stop(sd_icmp6_nd *nd) {
        assert_return(nd, -EINVAL);
        assert_return(nd->event, -EINVAL);

        log_icmp6_nd(client, "Stop ICMPv6");

        icmp6_nd_init(nd);

        nd->state = ICMP6_NEIGHBOR_DISCOVERY_IDLE;

        return 0;
}

int sd_icmp6_router_solicitation_start(sd_icmp6_nd *nd) {
        int r;

        assert(nd);
        assert(nd->event);

        if (nd->state != ICMP6_NEIGHBOR_DISCOVERY_IDLE)
                return -EINVAL;

        if (nd->index < 1)
                return -EINVAL;

        r = dhcp_network_icmp6_bind_router_solicitation(nd->index);
        if (r < 0)
                return r;

        nd->fd = r;

        r = sd_event_add_io(nd->event, &nd->recv, nd->fd, EPOLLIN,
                            icmp6_router_advertisment_recv, nd);
        if (r < 0)
                goto error;

        r = sd_event_source_set_priority(nd->recv, nd->event_priority);
        if (r < 0)
                goto error;

        r = sd_event_source_set_description(nd->recv, "icmp6-receive-message");
        if (r < 0)
                goto error;

        r = sd_event_add_time(nd->event, &nd->timeout, clock_boottime_or_monotonic(),
                              0, 0, icmp6_router_solicitation_timeout, nd);
        if (r < 0)
                goto error;

        r = sd_event_source_set_priority(nd->timeout, nd->event_priority);
        if (r < 0)
                goto error;

        r = sd_event_source_set_description(nd->timeout, "icmp6-timeout");
error:
        if (r < 0)
                icmp6_nd_init(nd);
        else
                log_icmp6_nd(client, "Start Router Solicitation");

        return r;
}
Commit	Line	Data
e3169126 PF	1	/***
	2	This file is part of systemd.
	3
	4	Copyright (C) 2014 Intel Corporation. All rights reserved.
	5
	6	systemd is free software; you can redistribute it and/or modify it
	7	under the terms of the GNU Lesser General Public License as published by
	8	the Free Software Foundation; either version 2.1 of the License, or
	9	(at your option) any later version.
	10
	11	systemd is distributed in the hope that it will be useful, but
	12	WITHOUT ANY WARRANTY; without even the implied warranty of
	13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	Lesser General Public License for more details.
	15
	16	You should have received a copy of the GNU Lesser General Public License
	17	along with systemd; If not, see <http://www.gnu.org/licenses/>.
	18	***/
	19
	20	#include <netinet/icmp6.h>
09667885	21	#include <netinet/ip6.h>
e3169126 PF	22	#include <string.h>
	23	#include <stdbool.h>
	24	#include <netinet/in.h>
09667885	25	#include <sys/ioctl.h>
e3169126 PF	26
	27	#include "socket-util.h"
	28	#include "refcnt.h"
	29	#include "async.h"
	30
	31	#include "dhcp6-internal.h"
	32	#include "sd-icmp6-nd.h"
	33
	34	#define ICMP6_ROUTER_SOLICITATION_INTERVAL 4 * USEC_PER_SEC
	35	#define ICMP6_MAX_ROUTER_SOLICITATIONS 3
	36
	37	enum icmp6_nd_state {
	38	ICMP6_NEIGHBOR_DISCOVERY_IDLE = 0,
	39	ICMP6_ROUTER_SOLICITATION_SENT = 10,
	40	ICMP6_ROUTER_ADVERTISMENT_LISTEN = 11,
	41	};
	42
09667885 PF	43	#define IP6_MIN_MTU (unsigned)1280
	44	#define ICMP6_ND_RECV_SIZE (IP6_MIN_MTU - sizeof(struct ip6_hdr))
	45	#define ICMP6_OPT_LEN_UNITS 8
	46
5624c480 PF	47	typedef struct ICMP6Prefix ICMP6Prefix;
	48
	49	struct ICMP6Prefix {
	50	RefCount n_ref;
	51
	52	LIST_FIELDS(ICMP6Prefix, prefixes);
	53
	54	uint8_t len;
	55	sd_event_source *timeout_valid;
	56	struct in6_addr addr;
	57	};
	58
e3169126 PF	59	struct sd_icmp6_nd {
	60	RefCount n_ref;
	61
	62	enum icmp6_nd_state state;
	63	sd_event *event;
	64	int event_priority;
	65	int index;
	66	struct ether_addr mac_addr;
5624c480 PF	67	uint32_t mtu;
5624c480 PF	68	LIST_HEAD(ICMP6Prefix, prefixes);
e3169126 PF	69	int fd;
	70	sd_event_source *recv;
	71	sd_event_source *timeout;
	72	int nd_sent;
	73	sd_icmp6_nd_callback_t callback;
	74	void *userdata;
	75	};
	76
79008bdd	77	#define log_icmp6_nd(p, fmt, ...) log_internal(LOG_DEBUG, 0, __FILE__, __LINE__, __func__, "ICMPv6 CLIENT: " fmt, ##__VA_ARGS__)
e3169126	78
5624c480 PF	79	static ICMP6Prefix icmp6_prefix_unref(ICMP6Prefix prefix) {
	80	if (prefix && REFCNT_DEC(prefix->n_ref) <= 0) {
	81	prefix->timeout_valid =
	82	sd_event_source_unref(prefix->timeout_valid);
	83
	84	free(prefix);
	85	}
	86
	87	return NULL;
	88	}
	89
	90	static int icmp6_prefix_new(ICMP6Prefix **ret) {
	91	_cleanup_free_ ICMP6Prefix *prefix = NULL;
	92
	93	assert(ret);
	94
	95	prefix = new0(ICMP6Prefix, 1);
	96	if (!prefix)
	97	return -ENOMEM;
	98
	99	prefix->n_ref = REFCNT_INIT;
	100	LIST_INIT(prefixes, prefix);
	101
	102	*ret = prefix;
	103	prefix = NULL;
	104
	105	return 0;
	106	}
	107
e3169126 PF	108	static void icmp6_nd_notify(sd_icmp6_nd *nd, int event)
	109	{
	110	if (nd->callback)
	111	nd->callback(nd, event, nd->userdata);
	112	}
	113
	114	int sd_icmp6_nd_set_callback(sd_icmp6_nd *nd, sd_icmp6_nd_callback_t callback,
	115	void *userdata) {
	116	assert(nd);
	117
	118	nd->callback = callback;
	119	nd->userdata = userdata;
	120
	121	return 0;
	122	}
	123
	124	int sd_icmp6_nd_set_index(sd_icmp6_nd *nd, int interface_index) {
	125	assert(nd);
	126	assert(interface_index >= -1);
	127
	128	nd->index = interface_index;
	129
	130	return 0;
	131	}
	132
	133	int sd_icmp6_nd_set_mac(sd_icmp6_nd nd, const struct ether_addr mac_addr) {
	134	assert(nd);
	135
	136	if (mac_addr)
	137	memcpy(&nd->mac_addr, mac_addr, sizeof(nd->mac_addr));
	138	else
eccaf899	139	zero(nd->mac_addr);
e3169126 PF	140
	141	return 0;
	142
	143	}
	144
	145	int sd_icmp6_nd_attach_event(sd_icmp6_nd nd, sd_event event, int priority) {
	146	int r;
	147
	148	assert_return(nd, -EINVAL);
	149	assert_return(!nd->event, -EBUSY);
	150
	151	if (event)
	152	nd->event = sd_event_ref(event);
	153	else {
	154	r = sd_event_default(&nd->event);
	155	if (r < 0)
	156	return 0;
	157	}
	158
	159	nd->event_priority = priority;
	160
	161	return 0;
	162	}
	163
	164	int sd_icmp6_nd_detach_event(sd_icmp6_nd *nd) {
	165	assert_return(nd, -EINVAL);
	166
	167	nd->event = sd_event_unref(nd->event);
	168
	169	return 0;
	170	}
	171
	172	sd_event sd_icmp6_nd_get_event(sd_icmp6_nd nd) {
	173	assert(nd);
	174
	175	return nd->event;
	176	}
	177
	178	sd_icmp6_nd sd_icmp6_nd_ref(sd_icmp6_nd nd) {
	179	assert (nd);
	180
	181	assert_se(REFCNT_INC(nd->n_ref) >= 2);
	182
	183	return nd;
	184	}
	185
	186	static int icmp6_nd_init(sd_icmp6_nd *nd) {
	187	assert(nd);
	188
	189	nd->recv = sd_event_source_unref(nd->recv);
	190	nd->fd = asynchronous_close(nd->fd);
	191	nd->timeout = sd_event_source_unref(nd->timeout);
	192
	193	return 0;
	194	}
	195
	196	sd_icmp6_nd sd_icmp6_nd_unref(sd_icmp6_nd nd) {
f0c4b1c3	197	if (nd && REFCNT_DEC(nd->n_ref) == 0) {
5624c480	198	ICMP6Prefix prefix, p;
e3169126 PF	199
	200	icmp6_nd_init(nd);
	201	sd_icmp6_nd_detach_event(nd);
	202
5624c480 PF	203	LIST_FOREACH_SAFE(prefixes, prefix, p, nd->prefixes) {
	204	LIST_REMOVE(prefixes, nd->prefixes, prefix);
	205
	206	prefix = icmp6_prefix_unref(prefix);
	207	}
	208
e3169126 PF	209	free(nd);
	210	}
	211
	212	return NULL;
	213	}
	214
	215	DEFINE_TRIVIAL_CLEANUP_FUNC(sd_icmp6_nd*, sd_icmp6_nd_unref);
	216	#define _cleanup_sd_icmp6_nd_free_ _cleanup_(sd_icmp6_nd_unrefp)
	217
	218	int sd_icmp6_nd_new(sd_icmp6_nd **ret) {
	219	_cleanup_sd_icmp6_nd_free_ sd_icmp6_nd *nd = NULL;
	220
	221	assert(ret);
	222
	223	nd = new0(sd_icmp6_nd, 1);
	224	if (!nd)
	225	return -ENOMEM;
	226
	227	nd->n_ref = REFCNT_INIT;
	228
	229	nd->index = -1;
03de7ed9	230	nd->fd = -1;
e3169126	231
5624c480 PF	232	LIST_HEAD_INIT(nd->prefixes);
5624c480 PF	233
e3169126 PF	234	*ret = nd;
	235	nd = NULL;
	236
	237	return 0;
	238	}
	239
d14b5bc6 PF	240	int sd_icmp6_ra_get_mtu(sd_icmp6_nd nd, uint32_t mtu) {
	241	assert_return(nd, -EINVAL);
	242	assert_return(mtu, -EINVAL);
	243
	244	if (nd->mtu == 0)
	245	return -ENOMSG;
	246
	247	*mtu = nd->mtu;
	248
	249	return 0;
	250	}
	251
09667885 PF	252	static int icmp6_ra_parse(sd_icmp6_nd nd, struct nd_router_advert ra,
	253	ssize_t len) {
	254	void *opt;
	255	struct nd_opt_hdr *opt_hdr;
	256
	257	assert_return(nd, -EINVAL);
	258	assert_return(ra, -EINVAL);
	259
	260	len -= sizeof(*ra);
	261	if (len < ICMP6_OPT_LEN_UNITS) {
	262	log_icmp6_nd(nd, "Router Advertisement below minimum length");
	263
	264	return -ENOMSG;
	265	}
	266
	267	opt = ra + 1;
	268	opt_hdr = opt;
	269
	270	while (len != 0 && len >= opt_hdr->nd_opt_len * ICMP6_OPT_LEN_UNITS) {
d14b5bc6 PF	271	struct nd_opt_mtu *opt_mtu;
d14b5bc6 PF	272	uint32_t mtu;
09667885 PF	273
	274	if (opt_hdr->nd_opt_len == 0)
	275	return -ENOMSG;
	276
	277	switch (opt_hdr->nd_opt_type) {
d14b5bc6 PF	278	case ND_OPT_MTU:
	279	opt_mtu = opt;
	280
	281	mtu = be32toh(opt_mtu->nd_opt_mtu_mtu);
	282
	283	if (mtu != nd->mtu) {
	284	nd->mtu = MAX(mtu, IP6_MIN_MTU);
	285
	286	log_icmp6_nd(nd, "Router Advertisement link MTU %d using %d",
	287	mtu, nd->mtu);
	288	}
	289
	290	break;
09667885 PF	291
	292	}
	293
	294	len -= opt_hdr->nd_opt_len * ICMP6_OPT_LEN_UNITS;
	295	opt = (void )((char )opt +
	296	opt_hdr->nd_opt_len * ICMP6_OPT_LEN_UNITS);
	297	opt_hdr = opt;
	298	}
	299
	300	if (len > 0)
	301	log_icmp6_nd(nd, "Router Advertisement contains %zd bytes of trailing garbage", len);
	302
	303	return 0;
	304	}
	305
e3169126 PF	306	static int icmp6_router_advertisment_recv(sd_event_source *s, int fd,
	307	uint32_t revents, void *userdata)
	308	{
	309	sd_icmp6_nd *nd = userdata;
09667885	310	int r, buflen = 0;
e3169126	311	ssize_t len;
09667885	312	_cleanup_free_ struct nd_router_advert *ra = NULL;
e3169126 PF	313	int event = ICMP6_EVENT_ROUTER_ADVERTISMENT_NONE;
	314
	315	assert(s);
	316	assert(nd);
	317	assert(nd->event);
	318
09667885 PF	319	r = ioctl(fd, FIONREAD, &buflen);
	320	if (r < 0 \|\| buflen <= 0)
	321	buflen = ICMP6_ND_RECV_SIZE;
	322
	323	ra = malloc(buflen);
	324	if (!ra)
	325	return -ENOMEM;
	326
	327	len = read(fd, ra, buflen);
	328	if (len < 0) {
	329	log_icmp6_nd(nd, "Could not receive message from UDP socket: %m");
e3169126	330	return 0;
09667885	331	}
e3169126	332
09667885	333	if (ra->nd_ra_type != ND_ROUTER_ADVERT)
e3169126 PF	334	return 0;
e3169126 PF	335
09667885	336	if (ra->nd_ra_code != 0)
e3169126 PF	337	return 0;
	338
	339	nd->timeout = sd_event_source_unref(nd->timeout);
	340
	341	nd->state = ICMP6_ROUTER_ADVERTISMENT_LISTEN;
	342
09667885	343	if (ra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER )
e3169126 PF	344	event = ICMP6_EVENT_ROUTER_ADVERTISMENT_OTHER;
e3169126 PF	345
09667885	346	if (ra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED)
e3169126 PF	347	event = ICMP6_EVENT_ROUTER_ADVERTISMENT_MANAGED;
e3169126 PF	348
06b643e7	349	log_icmp6_nd(nd, "Received Router Advertisement flags %s/%s",
09667885 PF	350	ra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED? "MANAGED": "none",
	351	ra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER? "OTHER": "none");
	352
	353	if (event != ICMP6_EVENT_ROUTER_ADVERTISMENT_NONE) {
	354	r = icmp6_ra_parse(nd, ra, len);
	355	if (r < 0) {
	356	log_icmp6_nd(nd, "Could not parse Router Advertisement: %s",
	357	strerror(-r));
	358	return 0;
	359	}
	360	}
e3169126 PF	361
	362	icmp6_nd_notify(nd, event);
	363
	364	return 0;
	365	}
	366
	367	static int icmp6_router_solicitation_timeout(sd_event_source *s, uint64_t usec,
	368	void *userdata)
	369	{
	370	sd_icmp6_nd *nd = userdata;
	371	uint64_t time_now, next_timeout;
	372	struct ether_addr unset = { };
	373	struct ether_addr *addr = NULL;
	374	int r;
	375
	376	assert(s);
	377	assert(nd);
	378	assert(nd->event);
	379
	380	nd->timeout = sd_event_source_unref(nd->timeout);
	381
	382	if (nd->nd_sent >= ICMP6_MAX_ROUTER_SOLICITATIONS) {
	383	icmp6_nd_notify(nd, ICMP6_EVENT_ROUTER_ADVERTISMENT_TIMEOUT);
	384	nd->state = ICMP6_ROUTER_ADVERTISMENT_LISTEN;
	385	} else {
	386	if (memcmp(&nd->mac_addr, &unset, sizeof(struct ether_addr)))
	387	addr = &nd->mac_addr;
	388
	389	r = dhcp_network_icmp6_send_router_solicitation(nd->fd, addr);
	390	if (r < 0)
	391	log_icmp6_nd(nd, "Error sending Router Solicitation");
	392	else {
	393	nd->state = ICMP6_ROUTER_SOLICITATION_SENT;
	394	log_icmp6_nd(nd, "Sent Router Solicitation");
	395	}
	396
	397	nd->nd_sent++;
	398
fa94c34b	399	r = sd_event_now(nd->event, clock_boottime_or_monotonic(), &time_now);
e3169126 PF	400	if (r < 0) {
	401	icmp6_nd_notify(nd, r);
	402	return 0;
	403	}
	404
	405	next_timeout = time_now + ICMP6_ROUTER_SOLICITATION_INTERVAL;
	406
fa94c34b	407	r = sd_event_add_time(nd->event, &nd->timeout, clock_boottime_or_monotonic(),
e3169126 PF	408	next_timeout, 0,
	409	icmp6_router_solicitation_timeout, nd);
	410	if (r < 0) {
	411	icmp6_nd_notify(nd, r);
	412	return 0;
	413	}
	414
	415	r = sd_event_source_set_priority(nd->timeout,
	416	nd->event_priority);
	417	if (r < 0) {
	418	icmp6_nd_notify(nd, r);
	419	return 0;
	420	}
9021bb9f	421
356779df	422	r = sd_event_source_set_description(nd->timeout, "icmp6-timeout");
9021bb9f TG	423	if (r < 0) {
	424	icmp6_nd_notify(nd, r);
	425	return 0;
	426	}
e3169126 PF	427	}
	428
	429	return 0;
	430	}
	431
836cf090 PF	432	int sd_icmp6_nd_stop(sd_icmp6_nd *nd) {
	433	assert_return(nd, -EINVAL);
	434	assert_return(nd->event, -EINVAL);
	435
	436	log_icmp6_nd(client, "Stop ICMPv6");
	437
	438	icmp6_nd_init(nd);
	439
	440	nd->state = ICMP6_NEIGHBOR_DISCOVERY_IDLE;
	441
	442	return 0;
	443	}
	444
e3169126 PF	445	int sd_icmp6_router_solicitation_start(sd_icmp6_nd *nd) {
	446	int r;
	447
	448	assert(nd);
	449	assert(nd->event);
	450
	451	if (nd->state != ICMP6_NEIGHBOR_DISCOVERY_IDLE)
	452	return -EINVAL;
	453
	454	if (nd->index < 1)
	455	return -EINVAL;
	456
	457	r = dhcp_network_icmp6_bind_router_solicitation(nd->index);
	458	if (r < 0)
	459	return r;
	460
	461	nd->fd = r;
	462
	463	r = sd_event_add_io(nd->event, &nd->recv, nd->fd, EPOLLIN,
	464	icmp6_router_advertisment_recv, nd);
	465	if (r < 0)
	466	goto error;
	467
	468	r = sd_event_source_set_priority(nd->recv, nd->event_priority);
	469	if (r < 0)
	470	goto error;
	471
356779df	472	r = sd_event_source_set_description(nd->recv, "icmp6-receive-message");
9021bb9f TG	473	if (r < 0)
	474	goto error;
	475
fa94c34b	476	r = sd_event_add_time(nd->event, &nd->timeout, clock_boottime_or_monotonic(),
e3169126 PF	477	0, 0, icmp6_router_solicitation_timeout, nd);
	478	if (r < 0)
	479	goto error;
	480
	481	r = sd_event_source_set_priority(nd->timeout, nd->event_priority);
9021bb9f TG	482	if (r < 0)
9021bb9f TG	483	goto error;
e3169126	484
356779df	485	r = sd_event_source_set_description(nd->timeout, "icmp6-timeout");
e3169126 PF	486	error:
	487	if (r < 0)
	488	icmp6_nd_init(nd);
	489	else
	490	log_icmp6_nd(client, "Start Router Solicitation");
	491
	492	return r;
	493	}