sd-icmp6-nd: rename files to sd-ndisc

The actual code rename will follow. The reason for the change of name is to make it
simpler and more uniform with how we name other libraries (we don't include the
underlying protocol). The new name also matches the naming in the kernel (which
is particularly relevent here as we expect to let the kernel do some parts of
the protocol and we do others).

1 files changed, 720 insertions, 0 deletions

diff --git a/src/libsystemd-network/sd-ndisc.c b/src/libsystemd-network/sd-ndisc.c
new file mode 100644
index 0000000000..8545344fd7
--- /dev/null
+++ b/src/libsystemd-network/sd-ndisc.c
@@ -0,0 +1,720 @@
+/***
+  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 "async.h"
+
+#include "dhcp6-internal.h"
+#include "sd-ndisc.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 {
+        unsigned n_ref;
+
+        LIST_FIELDS(ICMP6Prefix, prefixes);
+
+        uint8_t len;
+        sd_event_source *timeout_valid;
+        struct in6_addr addr;
+};
+
+struct sd_icmp6_nd {
+        unsigned n_ref;
+
+        enum icmp6_nd_state state;
+        sd_event *event;
+        int event_priority;
+        int index;
+        struct ether_addr mac_addr;
+        uint32_t mtu;
+        ICMP6Prefix *expired_prefix;
+        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)
+                return NULL;
+
+        assert(prefix->n_ref > 0);
+        prefix->n_ref--;
+
+        if (prefix->n_ref > 0)
+                return NULL;
+
+        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 = 1;
+        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) {
+
+        if (!nd)
+                return NULL;
+
+        assert(nd->n_ref > 0);
+        nd->n_ref++;
+
+        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) {
+        ICMP6Prefix *prefix, *p;
+
+        if (!nd)
+                return NULL;
+
+        assert(nd->n_ref > 0);
+        nd->n_ref--;
+
+        if (nd->n_ref > 0)
+                return NULL;
+
+        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 = 1;
+
+        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_prefix_timeout(sd_event_source *s, uint64_t usec,
+                                   void *userdata) {
+        sd_icmp6_nd *nd = userdata;
+        ICMP6Prefix *prefix, *p;
+
+        assert(nd);
+
+        LIST_FOREACH_SAFE(prefixes, prefix, p, nd->prefixes) {
+                if (prefix->timeout_valid != s)
+                        continue;
+
+                log_icmp6_nd(nd, "Prefix expired "SD_ICMP6_ND_ADDRESS_FORMAT_STR"/%d",
+                             SD_ICMP6_ND_ADDRESS_FORMAT_VAL(prefix->addr),
+                             prefix->len);
+
+                LIST_REMOVE(prefixes, nd->prefixes, prefix);
+
+                nd->expired_prefix = prefix;
+                icmp6_nd_notify(nd,
+                                SD_ICMP6_ND_EVENT_ROUTER_ADVERTISMENT_PREFIX_EXPIRED);
+                nd->expired_prefix = NULL;
+
+                prefix = icmp6_prefix_unref(prefix);
+
+                break;
+        }
+
+        return 0;
+}
+
+static int icmp6_ra_prefix_set_timeout(sd_icmp6_nd *nd,
+                                       ICMP6Prefix *prefix,
+                                       usec_t valid) {
+        usec_t time_now;
+        int r;
+
+        assert_return(prefix, -EINVAL);
+
+        r = sd_event_now(nd->event, clock_boottime_or_monotonic(), &time_now);
+        if (r < 0)
+                return r;
+
+        prefix->timeout_valid = sd_event_source_unref(prefix->timeout_valid);
+
+        r = sd_event_add_time(nd->event, &prefix->timeout_valid,
+                        clock_boottime_or_monotonic(), time_now + valid,
+                        USEC_PER_SEC, icmp6_ra_prefix_timeout, nd);
+        if (r < 0)
+                goto error;
+
+        r = sd_event_source_set_priority(prefix->timeout_valid,
+                                        nd->event_priority);
+        if (r < 0)
+                goto error;
+
+        r = sd_event_source_set_description(prefix->timeout_valid,
+                                        "icmp6-prefix-timeout");
+
+error:
+        if (r < 0)
+                prefix->timeout_valid =
+                        sd_event_source_unref(prefix->timeout_valid);
+
+        return r;
+}
+
+static int icmp6_prefix_match(const struct in6_addr *prefix, uint8_t prefixlen,
+                              const struct in6_addr *addr,
+                              uint8_t addr_prefixlen) {
+        uint8_t bytes, mask, len;
+
+        assert_return(prefix, -EINVAL);
+        assert_return(addr, -EINVAL);
+
+        len = MIN(prefixlen, addr_prefixlen);
+
+        bytes = len / 8;
+        mask = 0xff << (8 - len % 8);
+
+        if (memcmp(prefix, addr, bytes) != 0 ||
+            (prefix->s6_addr[bytes] & mask) != (addr->s6_addr[bytes] & mask))
+                return -EADDRNOTAVAIL;
+
+        return 0;
+}
+
+static int icmp6_ra_prefix_match(ICMP6Prefix *head, const struct in6_addr *addr,
+                                 uint8_t addr_len, ICMP6Prefix **result) {
+        ICMP6Prefix *prefix;
+
+        LIST_FOREACH(prefixes, prefix, head) {
+                if (icmp6_prefix_match(&prefix->addr, prefix->len, addr,
+                                       addr_len) >= 0) {
+                        *result = prefix;
+                        return 0;
+                }
+        }
+
+        return -EADDRNOTAVAIL;
+}
+
+int sd_icmp6_prefix_match(struct in6_addr *prefix, uint8_t prefixlen,
+                          struct in6_addr *addr) {
+        return icmp6_prefix_match(prefix, prefixlen, addr,
+                                  sizeof(addr->s6_addr) * 8);
+}
+
+int sd_icmp6_ra_get_prefixlen(sd_icmp6_nd *nd, const struct in6_addr *addr,
+                              uint8_t *prefixlen) {
+        int r;
+        ICMP6Prefix *prefix;
+
+        assert_return(nd, -EINVAL);
+        assert_return(addr, -EINVAL);
+        assert_return(prefixlen, -EINVAL);
+
+        r = icmp6_ra_prefix_match(nd->prefixes, addr,
+                                  sizeof(addr->s6_addr) * 8, &prefix);
+        if (r < 0)
+                return r;
+
+        *prefixlen = prefix->len;
+
+        return 0;
+}
+
+int sd_icmp6_ra_get_expired_prefix(sd_icmp6_nd *nd, struct in6_addr **addr, uint8_t *prefixlen) {
+        assert_return(nd, -EINVAL);
+        assert_return(addr, -EINVAL);
+        assert_return(prefixlen, -EINVAL);
+
+        if (!nd->expired_prefix)
+                return -EADDRNOTAVAIL;
+
+        *addr = &nd->expired_prefix->addr;
+        *prefixlen = nd->expired_prefix->len;
+
+        return 0;
+}
+
+static int icmp6_ra_prefix_update(sd_icmp6_nd *nd, ssize_t len,
+                                  const struct nd_opt_prefix_info *prefix_opt) {
+        int r;
+        ICMP6Prefix *prefix;
+        uint32_t lifetime;
+        char time_string[FORMAT_TIMESPAN_MAX];
+
+        assert_return(nd, -EINVAL);
+        assert_return(prefix_opt, -EINVAL);
+
+        if (len < prefix_opt->nd_opt_pi_len)
+                return -ENOMSG;
+
+        if (!(prefix_opt->nd_opt_pi_flags_reserved & ND_OPT_PI_FLAG_ONLINK))
+                return 0;
+
+        lifetime = be32toh(prefix_opt->nd_opt_pi_valid_time);
+
+        r = icmp6_ra_prefix_match(nd->prefixes,
+                                  &prefix_opt->nd_opt_pi_prefix,
+                                  prefix_opt->nd_opt_pi_prefix_len, &prefix);
+
+        if (r < 0 && r != -EADDRNOTAVAIL)
+                return r;
+
+        /* if router advertisment prefix valid timeout is zero, the timeout
+           callback will be called immediately to clean up the prefix */
+
+        if (r == -EADDRNOTAVAIL) {
+                r = icmp6_prefix_new(&prefix);
+                if (r < 0)
+                        return r;
+
+                prefix->len = prefix_opt->nd_opt_pi_prefix_len;
+
+                memcpy(&prefix->addr, &prefix_opt->nd_opt_pi_prefix,
+                        sizeof(prefix->addr));
+
+                log_icmp6_nd(nd, "New prefix "SD_ICMP6_ND_ADDRESS_FORMAT_STR"/%d lifetime %d expires in %s",
+                             SD_ICMP6_ND_ADDRESS_FORMAT_VAL(prefix->addr),
+                             prefix->len, lifetime,
+                             format_timespan(time_string, FORMAT_TIMESPAN_MAX, lifetime * USEC_PER_SEC, USEC_PER_SEC));
+
+                LIST_PREPEND(prefixes, nd->prefixes, prefix);
+
+        } else {
+                if (prefix->len != prefix_opt->nd_opt_pi_prefix_len) {
+                        uint8_t prefixlen;
+
+                        prefixlen = MIN(prefix->len, prefix_opt->nd_opt_pi_prefix_len);
+
+                        log_icmp6_nd(nd, "Prefix length mismatch %d/%d using %d",
+                                     prefix->len,
+                                     prefix_opt->nd_opt_pi_prefix_len,
+                                     prefixlen);
+
+                        prefix->len = prefixlen;
+                }
+
+                log_icmp6_nd(nd, "Update prefix "SD_ICMP6_ND_ADDRESS_FORMAT_STR"/%d lifetime %d expires in %s",
+                             SD_ICMP6_ND_ADDRESS_FORMAT_VAL(prefix->addr),
+                             prefix->len, lifetime,
+                             format_timespan(time_string, FORMAT_TIMESPAN_MAX, lifetime * USEC_PER_SEC, USEC_PER_SEC));
+        }
+
+        r = icmp6_ra_prefix_set_timeout(nd, prefix, lifetime * USEC_PER_SEC);
+
+        return r;
+}
+
+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;
+                struct nd_opt_prefix_info *opt_prefix;
+
+                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;
+
+                case ND_OPT_PREFIX_INFORMATION:
+                        opt_prefix = opt;
+
+                        icmp6_ra_prefix_update(nd, len, opt_prefix);
+
+                        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 = SD_ICMP6_ND_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 = SD_ICMP6_ND_EVENT_ROUTER_ADVERTISMENT_OTHER;
+
+        if (ra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED)
+                event = SD_ICMP6_ND_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 != SD_ICMP6_ND_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, SD_ICMP6_ND_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;
+}