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Diffstat (limited to 'src/libsystemd/sd-netlink/sd-netlink.c')
-rw-r--r--src/libsystemd/sd-netlink/sd-netlink.c921
1 files changed, 921 insertions, 0 deletions
diff --git a/src/libsystemd/sd-netlink/sd-netlink.c b/src/libsystemd/sd-netlink/sd-netlink.c
new file mode 100644
index 0000000..7801101
--- /dev/null
+++ b/src/libsystemd/sd-netlink/sd-netlink.c
@@ -0,0 +1,921 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <poll.h>
+
+#include "sd-netlink.h"
+
+#include "alloc-util.h"
+#include "fd-util.h"
+#include "hashmap.h"
+#include "io-util.h"
+#include "macro.h"
+#include "netlink-internal.h"
+#include "netlink-slot.h"
+#include "netlink-util.h"
+#include "process-util.h"
+#include "socket-util.h"
+#include "string-util.h"
+#include "util.h"
+
+static int sd_netlink_new(sd_netlink **ret) {
+ _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
+
+ assert_return(ret, -EINVAL);
+
+ rtnl = new(sd_netlink, 1);
+ if (!rtnl)
+ return -ENOMEM;
+
+ *rtnl = (sd_netlink) {
+ .n_ref = 1,
+ .fd = -1,
+ .sockaddr.nl.nl_family = AF_NETLINK,
+ .original_pid = getpid_cached(),
+ .protocol = -1,
+
+ /* Change notification responses have sequence 0, so we must
+ * start our request sequence numbers at 1, or we may confuse our
+ * responses with notifications from the kernel */
+ .serial = 1,
+
+ };
+
+ /* We guarantee that the read buffer has at least space for
+ * a message header */
+ if (!greedy_realloc((void**)&rtnl->rbuffer, &rtnl->rbuffer_allocated,
+ sizeof(struct nlmsghdr), sizeof(uint8_t)))
+ return -ENOMEM;
+
+ *ret = TAKE_PTR(rtnl);
+
+ return 0;
+}
+
+int sd_netlink_new_from_netlink(sd_netlink **ret, int fd) {
+ _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
+ socklen_t addrlen;
+ int r;
+
+ assert_return(ret, -EINVAL);
+
+ r = sd_netlink_new(&rtnl);
+ if (r < 0)
+ return r;
+
+ addrlen = sizeof(rtnl->sockaddr);
+
+ r = getsockname(fd, &rtnl->sockaddr.sa, &addrlen);
+ if (r < 0)
+ return -errno;
+
+ if (rtnl->sockaddr.nl.nl_family != AF_NETLINK)
+ return -EINVAL;
+
+ rtnl->fd = fd;
+
+ *ret = TAKE_PTR(rtnl);
+
+ return 0;
+}
+
+static bool rtnl_pid_changed(const sd_netlink *rtnl) {
+ assert(rtnl);
+
+ /* We don't support people creating an rtnl connection and
+ * keeping it around over a fork(). Let's complain. */
+
+ return rtnl->original_pid != getpid_cached();
+}
+
+int sd_netlink_open_fd(sd_netlink **ret, int fd) {
+ _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
+ int r;
+ int protocol;
+ socklen_t l;
+
+ assert_return(ret, -EINVAL);
+ assert_return(fd >= 0, -EBADF);
+
+ r = sd_netlink_new(&rtnl);
+ if (r < 0)
+ return r;
+
+ l = sizeof(protocol);
+ r = getsockopt(fd, SOL_SOCKET, SO_PROTOCOL, &protocol, &l);
+ if (r < 0)
+ return r;
+
+ rtnl->fd = fd;
+ rtnl->protocol = protocol;
+
+ r = setsockopt_int(fd, SOL_NETLINK, NETLINK_EXT_ACK, 1);
+ if (r < 0)
+ log_debug_errno(r, "sd-netlink: Failed to enable NETLINK_EXT_ACK option, ignoring: %m");
+
+ r = socket_bind(rtnl);
+ if (r < 0) {
+ rtnl->fd = -1; /* on failure, the caller remains owner of the fd, hence don't close it here */
+ rtnl->protocol = -1;
+ return r;
+ }
+
+ *ret = TAKE_PTR(rtnl);
+
+ return 0;
+}
+
+int netlink_open_family(sd_netlink **ret, int family) {
+ _cleanup_close_ int fd = -1;
+ int r;
+
+ fd = socket_open(family);
+ if (fd < 0)
+ return fd;
+
+ r = sd_netlink_open_fd(ret, fd);
+ if (r < 0)
+ return r;
+ TAKE_FD(fd);
+
+ return 0;
+}
+
+int sd_netlink_open(sd_netlink **ret) {
+ return netlink_open_family(ret, NETLINK_ROUTE);
+}
+
+int sd_netlink_inc_rcvbuf(sd_netlink *rtnl, size_t size) {
+ assert_return(rtnl, -EINVAL);
+ assert_return(!rtnl_pid_changed(rtnl), -ECHILD);
+
+ return fd_inc_rcvbuf(rtnl->fd, size);
+}
+
+static sd_netlink *netlink_free(sd_netlink *rtnl) {
+ sd_netlink_slot *s;
+ unsigned i;
+
+ assert(rtnl);
+
+ for (i = 0; i < rtnl->rqueue_size; i++)
+ sd_netlink_message_unref(rtnl->rqueue[i]);
+ free(rtnl->rqueue);
+
+ for (i = 0; i < rtnl->rqueue_partial_size; i++)
+ sd_netlink_message_unref(rtnl->rqueue_partial[i]);
+ free(rtnl->rqueue_partial);
+
+ free(rtnl->rbuffer);
+
+ while ((s = rtnl->slots)) {
+ assert(s->floating);
+ netlink_slot_disconnect(s, true);
+ }
+ hashmap_free(rtnl->reply_callbacks);
+ prioq_free(rtnl->reply_callbacks_prioq);
+
+ sd_event_source_unref(rtnl->io_event_source);
+ sd_event_source_unref(rtnl->time_event_source);
+ sd_event_unref(rtnl->event);
+
+ hashmap_free(rtnl->broadcast_group_refs);
+
+ hashmap_free(rtnl->genl_family_to_nlmsg_type);
+ hashmap_free(rtnl->nlmsg_type_to_genl_family);
+
+ safe_close(rtnl->fd);
+ return mfree(rtnl);
+}
+
+DEFINE_TRIVIAL_REF_UNREF_FUNC(sd_netlink, sd_netlink, netlink_free);
+
+static void rtnl_seal_message(sd_netlink *rtnl, sd_netlink_message *m) {
+ assert(rtnl);
+ assert(!rtnl_pid_changed(rtnl));
+ assert(m);
+ assert(m->hdr);
+
+ /* don't use seq == 0, as that is used for broadcasts, so we
+ would get confused by replies to such messages */
+ m->hdr->nlmsg_seq = rtnl->serial++ ? : rtnl->serial++;
+
+ rtnl_message_seal(m);
+
+ return;
+}
+
+int sd_netlink_send(sd_netlink *nl,
+ sd_netlink_message *message,
+ uint32_t *serial) {
+ int r;
+
+ assert_return(nl, -EINVAL);
+ assert_return(!rtnl_pid_changed(nl), -ECHILD);
+ assert_return(message, -EINVAL);
+ assert_return(!message->sealed, -EPERM);
+
+ rtnl_seal_message(nl, message);
+
+ r = socket_write_message(nl, message);
+ if (r < 0)
+ return r;
+
+ if (serial)
+ *serial = rtnl_message_get_serial(message);
+
+ return 1;
+}
+
+int rtnl_rqueue_make_room(sd_netlink *rtnl) {
+ assert(rtnl);
+
+ if (rtnl->rqueue_size >= RTNL_RQUEUE_MAX)
+ return log_debug_errno(SYNTHETIC_ERRNO(ENOBUFS),
+ "rtnl: exhausted the read queue size (%d)",
+ RTNL_RQUEUE_MAX);
+
+ if (!GREEDY_REALLOC(rtnl->rqueue, rtnl->rqueue_allocated, rtnl->rqueue_size + 1))
+ return -ENOMEM;
+
+ return 0;
+}
+
+int rtnl_rqueue_partial_make_room(sd_netlink *rtnl) {
+ assert(rtnl);
+
+ if (rtnl->rqueue_partial_size >= RTNL_RQUEUE_MAX)
+ return log_debug_errno(SYNTHETIC_ERRNO(ENOBUFS),
+ "rtnl: exhausted the partial read queue size (%d)",
+ RTNL_RQUEUE_MAX);
+
+ if (!GREEDY_REALLOC(rtnl->rqueue_partial, rtnl->rqueue_partial_allocated,
+ rtnl->rqueue_partial_size + 1))
+ return -ENOMEM;
+
+ return 0;
+}
+
+static int dispatch_rqueue(sd_netlink *rtnl, sd_netlink_message **message) {
+ int r;
+
+ assert(rtnl);
+ assert(message);
+
+ if (rtnl->rqueue_size <= 0) {
+ /* Try to read a new message */
+ r = socket_read_message(rtnl);
+ if (r == -ENOBUFS) { /* FIXME: ignore buffer overruns for now */
+ log_debug_errno(r, "Got ENOBUFS from netlink socket, ignoring.");
+ return 1;
+ }
+ if (r <= 0)
+ return r;
+ }
+
+ /* Dispatch a queued message */
+ *message = rtnl->rqueue[0];
+ rtnl->rqueue_size--;
+ memmove(rtnl->rqueue, rtnl->rqueue + 1, sizeof(sd_netlink_message*) * rtnl->rqueue_size);
+
+ return 1;
+}
+
+static int process_timeout(sd_netlink *rtnl) {
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
+ struct reply_callback *c;
+ sd_netlink_slot *slot;
+ usec_t n;
+ int r;
+
+ assert(rtnl);
+
+ c = prioq_peek(rtnl->reply_callbacks_prioq);
+ if (!c)
+ return 0;
+
+ n = now(CLOCK_MONOTONIC);
+ if (c->timeout > n)
+ return 0;
+
+ r = rtnl_message_new_synthetic_error(rtnl, -ETIMEDOUT, c->serial, &m);
+ if (r < 0)
+ return r;
+
+ assert_se(prioq_pop(rtnl->reply_callbacks_prioq) == c);
+ c->timeout = 0;
+ hashmap_remove(rtnl->reply_callbacks, &c->serial);
+
+ slot = container_of(c, sd_netlink_slot, reply_callback);
+
+ r = c->callback(rtnl, m, slot->userdata);
+ if (r < 0)
+ log_debug_errno(r, "sd-netlink: timedout callback %s%s%sfailed: %m",
+ slot->description ? "'" : "",
+ strempty(slot->description),
+ slot->description ? "' " : "");
+
+ if (slot->floating)
+ netlink_slot_disconnect(slot, true);
+
+ return 1;
+}
+
+static int process_reply(sd_netlink *rtnl, sd_netlink_message *m) {
+ struct reply_callback *c;
+ sd_netlink_slot *slot;
+ uint64_t serial;
+ uint16_t type;
+ int r;
+
+ assert(rtnl);
+ assert(m);
+
+ serial = rtnl_message_get_serial(m);
+ c = hashmap_remove(rtnl->reply_callbacks, &serial);
+ if (!c)
+ return 0;
+
+ if (c->timeout != 0) {
+ prioq_remove(rtnl->reply_callbacks_prioq, c, &c->prioq_idx);
+ c->timeout = 0;
+ }
+
+ r = sd_netlink_message_get_type(m, &type);
+ if (r < 0)
+ return r;
+
+ if (type == NLMSG_DONE)
+ m = NULL;
+
+ slot = container_of(c, sd_netlink_slot, reply_callback);
+
+ r = c->callback(rtnl, m, slot->userdata);
+ if (r < 0)
+ log_debug_errno(r, "sd-netlink: reply callback %s%s%sfailed: %m",
+ slot->description ? "'" : "",
+ strempty(slot->description),
+ slot->description ? "' " : "");
+
+ if (slot->floating)
+ netlink_slot_disconnect(slot, true);
+
+ return 1;
+}
+
+static int process_match(sd_netlink *rtnl, sd_netlink_message *m) {
+ struct match_callback *c;
+ sd_netlink_slot *slot;
+ uint16_t type;
+ int r;
+
+ assert(rtnl);
+ assert(m);
+
+ r = sd_netlink_message_get_type(m, &type);
+ if (r < 0)
+ return r;
+
+ LIST_FOREACH(match_callbacks, c, rtnl->match_callbacks) {
+ if (type == c->type) {
+ slot = container_of(c, sd_netlink_slot, match_callback);
+
+ r = c->callback(rtnl, m, slot->userdata);
+ if (r != 0) {
+ if (r < 0)
+ log_debug_errno(r, "sd-netlink: match callback %s%s%sfailed: %m",
+ slot->description ? "'" : "",
+ strempty(slot->description),
+ slot->description ? "' " : "");
+
+ break;
+ }
+ }
+ }
+
+ return 1;
+}
+
+static int process_running(sd_netlink *rtnl, sd_netlink_message **ret) {
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
+ int r;
+
+ assert(rtnl);
+
+ r = process_timeout(rtnl);
+ if (r != 0)
+ goto null_message;
+
+ r = dispatch_rqueue(rtnl, &m);
+ if (r < 0)
+ return r;
+ if (!m)
+ goto null_message;
+
+ if (sd_netlink_message_is_broadcast(m)) {
+ r = process_match(rtnl, m);
+ if (r != 0)
+ goto null_message;
+ } else {
+ r = process_reply(rtnl, m);
+ if (r != 0)
+ goto null_message;
+ }
+
+ if (ret) {
+ *ret = TAKE_PTR(m);
+
+ return 1;
+ }
+
+ return 1;
+
+null_message:
+ if (r >= 0 && ret)
+ *ret = NULL;
+
+ return r;
+}
+
+int sd_netlink_process(sd_netlink *rtnl, sd_netlink_message **ret) {
+ NETLINK_DONT_DESTROY(rtnl);
+ int r;
+
+ assert_return(rtnl, -EINVAL);
+ assert_return(!rtnl_pid_changed(rtnl), -ECHILD);
+ assert_return(!rtnl->processing, -EBUSY);
+
+ rtnl->processing = true;
+ r = process_running(rtnl, ret);
+ rtnl->processing = false;
+
+ return r;
+}
+
+static usec_t calc_elapse(uint64_t usec) {
+ if (usec == (uint64_t) -1)
+ return 0;
+
+ if (usec == 0)
+ usec = RTNL_DEFAULT_TIMEOUT;
+
+ return now(CLOCK_MONOTONIC) + usec;
+}
+
+static int rtnl_poll(sd_netlink *rtnl, bool need_more, uint64_t timeout_usec) {
+ usec_t m = USEC_INFINITY;
+ int r, e;
+
+ assert(rtnl);
+
+ e = sd_netlink_get_events(rtnl);
+ if (e < 0)
+ return e;
+
+ if (need_more)
+ /* Caller wants more data, and doesn't care about
+ * what's been read or any other timeouts. */
+ e |= POLLIN;
+ else {
+ usec_t until;
+ /* Caller wants to process if there is something to
+ * process, but doesn't care otherwise */
+
+ r = sd_netlink_get_timeout(rtnl, &until);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ usec_t nw;
+ nw = now(CLOCK_MONOTONIC);
+ m = until > nw ? until - nw : 0;
+ }
+ }
+
+ if (timeout_usec != (uint64_t) -1 && (m == USEC_INFINITY || timeout_usec < m))
+ m = timeout_usec;
+
+ r = fd_wait_for_event(rtnl->fd, e, m);
+ if (r <= 0)
+ return r;
+
+ return 1;
+}
+
+int sd_netlink_wait(sd_netlink *nl, uint64_t timeout_usec) {
+ assert_return(nl, -EINVAL);
+ assert_return(!rtnl_pid_changed(nl), -ECHILD);
+
+ if (nl->rqueue_size > 0)
+ return 0;
+
+ return rtnl_poll(nl, false, timeout_usec);
+}
+
+static int timeout_compare(const void *a, const void *b) {
+ const struct reply_callback *x = a, *y = b;
+
+ if (x->timeout != 0 && y->timeout == 0)
+ return -1;
+
+ if (x->timeout == 0 && y->timeout != 0)
+ return 1;
+
+ return CMP(x->timeout, y->timeout);
+}
+
+int sd_netlink_call_async(
+ sd_netlink *nl,
+ sd_netlink_slot **ret_slot,
+ sd_netlink_message *m,
+ sd_netlink_message_handler_t callback,
+ sd_netlink_destroy_t destroy_callback,
+ void *userdata,
+ uint64_t usec,
+ const char *description) {
+ _cleanup_free_ sd_netlink_slot *slot = NULL;
+ uint32_t s;
+ int r, k;
+
+ assert_return(nl, -EINVAL);
+ assert_return(m, -EINVAL);
+ assert_return(callback, -EINVAL);
+ assert_return(!rtnl_pid_changed(nl), -ECHILD);
+
+ r = hashmap_ensure_allocated(&nl->reply_callbacks, &uint64_hash_ops);
+ if (r < 0)
+ return r;
+
+ if (usec != (uint64_t) -1) {
+ r = prioq_ensure_allocated(&nl->reply_callbacks_prioq, timeout_compare);
+ if (r < 0)
+ return r;
+ }
+
+ r = netlink_slot_allocate(nl, !ret_slot, NETLINK_REPLY_CALLBACK, sizeof(struct reply_callback), userdata, description, &slot);
+ if (r < 0)
+ return r;
+
+ slot->reply_callback.callback = callback;
+ slot->reply_callback.timeout = calc_elapse(usec);
+
+ k = sd_netlink_send(nl, m, &s);
+ if (k < 0)
+ return k;
+
+ slot->reply_callback.serial = s;
+
+ r = hashmap_put(nl->reply_callbacks, &slot->reply_callback.serial, &slot->reply_callback);
+ if (r < 0)
+ return r;
+
+ if (slot->reply_callback.timeout != 0) {
+ r = prioq_put(nl->reply_callbacks_prioq, &slot->reply_callback, &slot->reply_callback.prioq_idx);
+ if (r < 0) {
+ (void) hashmap_remove(nl->reply_callbacks, &slot->reply_callback.serial);
+ return r;
+ }
+ }
+
+ /* Set this at last. Otherwise, some failures in above call the destroy callback but some do not. */
+ slot->destroy_callback = destroy_callback;
+
+ if (ret_slot)
+ *ret_slot = slot;
+
+ TAKE_PTR(slot);
+
+ return k;
+}
+
+int sd_netlink_call(sd_netlink *rtnl,
+ sd_netlink_message *message,
+ uint64_t usec,
+ sd_netlink_message **ret) {
+ usec_t timeout;
+ uint32_t serial;
+ int r;
+
+ assert_return(rtnl, -EINVAL);
+ assert_return(!rtnl_pid_changed(rtnl), -ECHILD);
+ assert_return(message, -EINVAL);
+
+ r = sd_netlink_send(rtnl, message, &serial);
+ if (r < 0)
+ return r;
+
+ timeout = calc_elapse(usec);
+
+ for (;;) {
+ usec_t left;
+ unsigned i;
+
+ for (i = 0; i < rtnl->rqueue_size; i++) {
+ uint32_t received_serial;
+
+ received_serial = rtnl_message_get_serial(rtnl->rqueue[i]);
+
+ if (received_serial == serial) {
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *incoming = NULL;
+ uint16_t type;
+
+ incoming = rtnl->rqueue[i];
+
+ /* found a match, remove from rqueue and return it */
+ memmove(rtnl->rqueue + i,rtnl->rqueue + i + 1,
+ sizeof(sd_netlink_message*) * (rtnl->rqueue_size - i - 1));
+ rtnl->rqueue_size--;
+
+ r = sd_netlink_message_get_errno(incoming);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_get_type(incoming, &type);
+ if (r < 0)
+ return r;
+
+ if (type == NLMSG_DONE) {
+ *ret = NULL;
+ return 0;
+ }
+
+ if (ret)
+ *ret = TAKE_PTR(incoming);
+
+ return 1;
+ }
+ }
+
+ r = socket_read_message(rtnl);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ /* received message, so try to process straight away */
+ continue;
+
+ if (timeout > 0) {
+ usec_t n;
+
+ n = now(CLOCK_MONOTONIC);
+ if (n >= timeout)
+ return -ETIMEDOUT;
+
+ left = timeout - n;
+ } else
+ left = (uint64_t) -1;
+
+ r = rtnl_poll(rtnl, true, left);
+ if (r < 0)
+ return r;
+ else if (r == 0)
+ return -ETIMEDOUT;
+ }
+}
+
+int sd_netlink_get_events(const sd_netlink *rtnl) {
+ assert_return(rtnl, -EINVAL);
+ assert_return(!rtnl_pid_changed(rtnl), -ECHILD);
+
+ if (rtnl->rqueue_size == 0)
+ return POLLIN;
+ else
+ return 0;
+}
+
+int sd_netlink_get_timeout(const sd_netlink *rtnl, uint64_t *timeout_usec) {
+ struct reply_callback *c;
+
+ assert_return(rtnl, -EINVAL);
+ assert_return(timeout_usec, -EINVAL);
+ assert_return(!rtnl_pid_changed(rtnl), -ECHILD);
+
+ if (rtnl->rqueue_size > 0) {
+ *timeout_usec = 0;
+ return 1;
+ }
+
+ c = prioq_peek(rtnl->reply_callbacks_prioq);
+ if (!c) {
+ *timeout_usec = (uint64_t) -1;
+ return 0;
+ }
+
+ *timeout_usec = c->timeout;
+
+ return 1;
+}
+
+static int io_callback(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+ sd_netlink *rtnl = userdata;
+ int r;
+
+ assert(rtnl);
+
+ r = sd_netlink_process(rtnl, NULL);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+static int time_callback(sd_event_source *s, uint64_t usec, void *userdata) {
+ sd_netlink *rtnl = userdata;
+ int r;
+
+ assert(rtnl);
+
+ r = sd_netlink_process(rtnl, NULL);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+static int prepare_callback(sd_event_source *s, void *userdata) {
+ sd_netlink *rtnl = userdata;
+ int r, e;
+ usec_t until;
+
+ assert(s);
+ assert(rtnl);
+
+ e = sd_netlink_get_events(rtnl);
+ if (e < 0)
+ return e;
+
+ r = sd_event_source_set_io_events(rtnl->io_event_source, e);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_get_timeout(rtnl, &until);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ int j;
+
+ j = sd_event_source_set_time(rtnl->time_event_source, until);
+ if (j < 0)
+ return j;
+ }
+
+ r = sd_event_source_set_enabled(rtnl->time_event_source, r > 0);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+int sd_netlink_attach_event(sd_netlink *rtnl, sd_event *event, int64_t priority) {
+ int r;
+
+ assert_return(rtnl, -EINVAL);
+ assert_return(!rtnl->event, -EBUSY);
+
+ assert(!rtnl->io_event_source);
+ assert(!rtnl->time_event_source);
+
+ if (event)
+ rtnl->event = sd_event_ref(event);
+ else {
+ r = sd_event_default(&rtnl->event);
+ if (r < 0)
+ return r;
+ }
+
+ r = sd_event_add_io(rtnl->event, &rtnl->io_event_source, rtnl->fd, 0, io_callback, rtnl);
+ if (r < 0)
+ goto fail;
+
+ r = sd_event_source_set_priority(rtnl->io_event_source, priority);
+ if (r < 0)
+ goto fail;
+
+ r = sd_event_source_set_description(rtnl->io_event_source, "rtnl-receive-message");
+ if (r < 0)
+ goto fail;
+
+ r = sd_event_source_set_prepare(rtnl->io_event_source, prepare_callback);
+ if (r < 0)
+ goto fail;
+
+ r = sd_event_add_time(rtnl->event, &rtnl->time_event_source, CLOCK_MONOTONIC, 0, 0, time_callback, rtnl);
+ if (r < 0)
+ goto fail;
+
+ r = sd_event_source_set_priority(rtnl->time_event_source, priority);
+ if (r < 0)
+ goto fail;
+
+ r = sd_event_source_set_description(rtnl->time_event_source, "rtnl-timer");
+ if (r < 0)
+ goto fail;
+
+ return 0;
+
+fail:
+ sd_netlink_detach_event(rtnl);
+ return r;
+}
+
+int sd_netlink_detach_event(sd_netlink *rtnl) {
+ assert_return(rtnl, -EINVAL);
+ assert_return(rtnl->event, -ENXIO);
+
+ rtnl->io_event_source = sd_event_source_unref(rtnl->io_event_source);
+
+ rtnl->time_event_source = sd_event_source_unref(rtnl->time_event_source);
+
+ rtnl->event = sd_event_unref(rtnl->event);
+
+ return 0;
+}
+
+int sd_netlink_add_match(
+ sd_netlink *rtnl,
+ sd_netlink_slot **ret_slot,
+ uint16_t type,
+ sd_netlink_message_handler_t callback,
+ sd_netlink_destroy_t destroy_callback,
+ void *userdata,
+ const char *description) {
+ _cleanup_free_ sd_netlink_slot *slot = NULL;
+ int r;
+
+ assert_return(rtnl, -EINVAL);
+ assert_return(callback, -EINVAL);
+ assert_return(!rtnl_pid_changed(rtnl), -ECHILD);
+
+ r = netlink_slot_allocate(rtnl, !ret_slot, NETLINK_MATCH_CALLBACK, sizeof(struct match_callback), userdata, description, &slot);
+ if (r < 0)
+ return r;
+
+ slot->match_callback.callback = callback;
+ slot->match_callback.type = type;
+
+ switch (type) {
+ case RTM_NEWLINK:
+ case RTM_DELLINK:
+ r = socket_broadcast_group_ref(rtnl, RTNLGRP_LINK);
+ if (r < 0)
+ return r;
+
+ break;
+ case RTM_NEWADDR:
+ case RTM_DELADDR:
+ r = socket_broadcast_group_ref(rtnl, RTNLGRP_IPV4_IFADDR);
+ if (r < 0)
+ return r;
+
+ r = socket_broadcast_group_ref(rtnl, RTNLGRP_IPV6_IFADDR);
+ if (r < 0)
+ return r;
+
+ break;
+ case RTM_NEWNEIGH:
+ case RTM_DELNEIGH:
+ r = socket_broadcast_group_ref(rtnl, RTNLGRP_NEIGH);
+ if (r < 0)
+ return r;
+
+ break;
+ case RTM_NEWROUTE:
+ case RTM_DELROUTE:
+ r = socket_broadcast_group_ref(rtnl, RTNLGRP_IPV4_ROUTE);
+ if (r < 0)
+ return r;
+
+ r = socket_broadcast_group_ref(rtnl, RTNLGRP_IPV6_ROUTE);
+ if (r < 0)
+ return r;
+ break;
+ case RTM_NEWRULE:
+ case RTM_DELRULE:
+ r = socket_broadcast_group_ref(rtnl, RTNLGRP_IPV4_RULE);
+ if (r < 0)
+ return r;
+
+ r = socket_broadcast_group_ref(rtnl, RTNLGRP_IPV6_RULE);
+ if (r < 0)
+ return r;
+ break;
+ case RTM_NEWNEXTHOP:
+ case RTM_DELNEXTHOP:
+ r = socket_broadcast_group_ref(rtnl, RTNLGRP_NEXTHOP);
+ if (r < 0)
+ return r;
+ break;
+
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ LIST_PREPEND(match_callbacks, rtnl->match_callbacks, &slot->match_callback);
+
+ /* Set this at last. Otherwise, some failures in above call the destroy callback but some do not. */
+ slot->destroy_callback = destroy_callback;
+
+ if (ret_slot)
+ *ret_slot = slot;
+
+ TAKE_PTR(slot);
+
+ return 0;
+}