diff options
Diffstat (limited to 'src/libsystemd-network/sd-ipv4acd.c')
| -rw-r--r-- | src/libsystemd-network/sd-ipv4acd.c | 524 |
1 files changed, 0 insertions, 524 deletions
diff --git a/src/libsystemd-network/sd-ipv4acd.c b/src/libsystemd-network/sd-ipv4acd.c deleted file mode 100644 index 4dd343c101..0000000000 --- a/src/libsystemd-network/sd-ipv4acd.c +++ /dev/null @@ -1,524 +0,0 @@ -/*** - This file is part of systemd. - - Copyright (C) 2014 Axis Communications AB. All rights reserved. - Copyright (C) 2015 Tom Gundersen - - systemd is free software; you can redistribute it and/or modify it - under the terms of the GNU Lesser General Public License as published by - the Free Software Foundation; either version 2.1 of the License, or - (at your option) any later version. - - systemd is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see <http://www.gnu.org/licenses/>. -***/ - -#include <arpa/inet.h> -#include <errno.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> - -#include "sd-ipv4acd.h" - -#include "alloc-util.h" -#include "arp-util.h" -#include "ether-addr-util.h" -#include "fd-util.h" -#include "in-addr-util.h" -#include "list.h" -#include "random-util.h" -#include "siphash24.h" -#include "string-util.h" -#include "util.h" - -/* Constants from the RFC */ -#define PROBE_WAIT_USEC (1U * USEC_PER_SEC) -#define PROBE_NUM 3U -#define PROBE_MIN_USEC (1U * USEC_PER_SEC) -#define PROBE_MAX_USEC (2U * USEC_PER_SEC) -#define ANNOUNCE_WAIT_USEC (2U * USEC_PER_SEC) -#define ANNOUNCE_NUM 2U -#define ANNOUNCE_INTERVAL_USEC (2U * USEC_PER_SEC) -#define MAX_CONFLICTS 10U -#define RATE_LIMIT_INTERVAL_USEC (60U * USEC_PER_SEC) -#define DEFEND_INTERVAL_USEC (10U * USEC_PER_SEC) - -typedef enum IPv4ACDState { - IPV4ACD_STATE_INIT, - IPV4ACD_STATE_STARTED, - IPV4ACD_STATE_WAITING_PROBE, - IPV4ACD_STATE_PROBING, - IPV4ACD_STATE_WAITING_ANNOUNCE, - IPV4ACD_STATE_ANNOUNCING, - IPV4ACD_STATE_RUNNING, - _IPV4ACD_STATE_MAX, - _IPV4ACD_STATE_INVALID = -1 -} IPv4ACDState; - -struct sd_ipv4acd { - unsigned n_ref; - - IPv4ACDState state; - int ifindex; - int fd; - - unsigned n_iteration; - unsigned n_conflict; - - sd_event_source *receive_message_event_source; - sd_event_source *timer_event_source; - - usec_t defend_window; - be32_t address; - - /* External */ - struct ether_addr mac_addr; - - sd_event *event; - int event_priority; - sd_ipv4acd_callback_t callback; - void* userdata; -}; - -#define log_ipv4acd_errno(acd, error, fmt, ...) log_internal(LOG_DEBUG, error, __FILE__, __LINE__, __func__, "IPV4ACD: " fmt, ##__VA_ARGS__) -#define log_ipv4acd(acd, fmt, ...) log_ipv4acd_errno(acd, 0, fmt, ##__VA_ARGS__) - -static void ipv4acd_set_state(sd_ipv4acd *acd, IPv4ACDState st, bool reset_counter) { - assert(acd); - assert(st < _IPV4ACD_STATE_MAX); - - if (st == acd->state && !reset_counter) - acd->n_iteration++; - else { - acd->state = st; - acd->n_iteration = 0; - } -} - -static void ipv4acd_reset(sd_ipv4acd *acd) { - assert(acd); - - acd->timer_event_source = sd_event_source_unref(acd->timer_event_source); - acd->receive_message_event_source = sd_event_source_unref(acd->receive_message_event_source); - - acd->fd = safe_close(acd->fd); - - ipv4acd_set_state(acd, IPV4ACD_STATE_INIT, true); -} - -sd_ipv4acd *sd_ipv4acd_ref(sd_ipv4acd *acd) { - if (!acd) - return NULL; - - assert_se(acd->n_ref >= 1); - acd->n_ref++; - - return acd; -} - -sd_ipv4acd *sd_ipv4acd_unref(sd_ipv4acd *acd) { - if (!acd) - return NULL; - - assert_se(acd->n_ref >= 1); - acd->n_ref--; - - if (acd->n_ref > 0) - return NULL; - - ipv4acd_reset(acd); - sd_ipv4acd_detach_event(acd); - - return mfree(acd); -} - -int sd_ipv4acd_new(sd_ipv4acd **ret) { - _cleanup_(sd_ipv4acd_unrefp) sd_ipv4acd *acd = NULL; - - assert_return(ret, -EINVAL); - - acd = new0(sd_ipv4acd, 1); - if (!acd) - return -ENOMEM; - - acd->n_ref = 1; - acd->state = IPV4ACD_STATE_INIT; - acd->ifindex = -1; - acd->fd = -1; - - *ret = acd; - acd = NULL; - - return 0; -} - -static void ipv4acd_client_notify(sd_ipv4acd *acd, int event) { - assert(acd); - - if (!acd->callback) - return; - - acd->callback(acd, event, acd->userdata); -} - -int sd_ipv4acd_stop(sd_ipv4acd *acd) { - assert_return(acd, -EINVAL); - - ipv4acd_reset(acd); - - log_ipv4acd(acd, "STOPPED"); - - ipv4acd_client_notify(acd, SD_IPV4ACD_EVENT_STOP); - - return 0; -} - -static int ipv4acd_on_timeout(sd_event_source *s, uint64_t usec, void *userdata); - -static int ipv4acd_set_next_wakeup(sd_ipv4acd *acd, usec_t usec, usec_t random_usec) { - _cleanup_(sd_event_source_unrefp) sd_event_source *timer = NULL; - usec_t next_timeout, time_now; - int r; - - assert(acd); - - next_timeout = usec; - - if (random_usec > 0) - next_timeout += (usec_t) random_u64() % random_usec; - - assert_se(sd_event_now(acd->event, clock_boottime_or_monotonic(), &time_now) >= 0); - - r = sd_event_add_time(acd->event, &timer, clock_boottime_or_monotonic(), time_now + next_timeout, 0, ipv4acd_on_timeout, acd); - if (r < 0) - return r; - - r = sd_event_source_set_priority(timer, acd->event_priority); - if (r < 0) - return r; - - (void) sd_event_source_set_description(timer, "ipv4acd-timer"); - - sd_event_source_unref(acd->timer_event_source); - acd->timer_event_source = timer; - timer = NULL; - - return 0; -} - -static bool ipv4acd_arp_conflict(sd_ipv4acd *acd, struct ether_arp *arp) { - assert(acd); - assert(arp); - - /* see the BPF */ - if (memcmp(arp->arp_spa, &acd->address, sizeof(acd->address)) == 0) - return true; - - /* the TPA matched instead of the SPA, this is not a conflict */ - return false; -} - -static int ipv4acd_on_timeout(sd_event_source *s, uint64_t usec, void *userdata) { - sd_ipv4acd *acd = userdata; - int r = 0; - - assert(acd); - - switch (acd->state) { - - case IPV4ACD_STATE_STARTED: - ipv4acd_set_state(acd, IPV4ACD_STATE_WAITING_PROBE, true); - - if (acd->n_conflict >= MAX_CONFLICTS) { - char ts[FORMAT_TIMESPAN_MAX]; - log_ipv4acd(acd, "Max conflicts reached, delaying by %s", format_timespan(ts, sizeof(ts), RATE_LIMIT_INTERVAL_USEC, 0)); - - r = ipv4acd_set_next_wakeup(acd, RATE_LIMIT_INTERVAL_USEC, PROBE_WAIT_USEC); - if (r < 0) - goto fail; - - acd->n_conflict = 0; - } else { - r = ipv4acd_set_next_wakeup(acd, 0, PROBE_WAIT_USEC); - if (r < 0) - goto fail; - } - - break; - - case IPV4ACD_STATE_WAITING_PROBE: - case IPV4ACD_STATE_PROBING: - /* Send a probe */ - r = arp_send_probe(acd->fd, acd->ifindex, acd->address, &acd->mac_addr); - if (r < 0) { - log_ipv4acd_errno(acd, r, "Failed to send ARP probe: %m"); - goto fail; - } else { - _cleanup_free_ char *address = NULL; - union in_addr_union addr = { .in.s_addr = acd->address }; - - (void) in_addr_to_string(AF_INET, &addr, &address); - log_ipv4acd(acd, "Probing %s", strna(address)); - } - - if (acd->n_iteration < PROBE_NUM - 2) { - ipv4acd_set_state(acd, IPV4ACD_STATE_PROBING, false); - - r = ipv4acd_set_next_wakeup(acd, PROBE_MIN_USEC, (PROBE_MAX_USEC-PROBE_MIN_USEC)); - if (r < 0) - goto fail; - } else { - ipv4acd_set_state(acd, IPV4ACD_STATE_WAITING_ANNOUNCE, true); - - r = ipv4acd_set_next_wakeup(acd, ANNOUNCE_WAIT_USEC, 0); - if (r < 0) - goto fail; - } - - break; - - case IPV4ACD_STATE_ANNOUNCING: - if (acd->n_iteration >= ANNOUNCE_NUM - 1) { - ipv4acd_set_state(acd, IPV4ACD_STATE_RUNNING, false); - break; - } - - /* fall through */ - - case IPV4ACD_STATE_WAITING_ANNOUNCE: - /* Send announcement packet */ - r = arp_send_announcement(acd->fd, acd->ifindex, acd->address, &acd->mac_addr); - if (r < 0) { - log_ipv4acd_errno(acd, r, "Failed to send ARP announcement: %m"); - goto fail; - } else - log_ipv4acd(acd, "ANNOUNCE"); - - ipv4acd_set_state(acd, IPV4ACD_STATE_ANNOUNCING, false); - - r = ipv4acd_set_next_wakeup(acd, ANNOUNCE_INTERVAL_USEC, 0); - if (r < 0) - goto fail; - - if (acd->n_iteration == 0) { - acd->n_conflict = 0; - ipv4acd_client_notify(acd, SD_IPV4ACD_EVENT_BIND); - } - - break; - - default: - assert_not_reached("Invalid state."); - } - - return 0; - -fail: - sd_ipv4acd_stop(acd); - return 0; -} - -static void ipv4acd_on_conflict(sd_ipv4acd *acd) { - _cleanup_free_ char *address = NULL; - union in_addr_union addr = { .in.s_addr = acd->address }; - - assert(acd); - - acd->n_conflict++; - - (void) in_addr_to_string(AF_INET, &addr, &address); - log_ipv4acd(acd, "Conflict on %s (%u)", strna(address), acd->n_conflict); - - ipv4acd_reset(acd); - ipv4acd_client_notify(acd, SD_IPV4ACD_EVENT_CONFLICT); -} - -static int ipv4acd_on_packet( - sd_event_source *s, - int fd, - uint32_t revents, - void *userdata) { - - sd_ipv4acd *acd = userdata; - struct ether_arp packet; - ssize_t n; - int r; - - assert(s); - assert(acd); - assert(fd >= 0); - - n = recv(fd, &packet, sizeof(struct ether_arp), 0); - if (n < 0) { - if (errno == EAGAIN || errno == EINTR) - return 0; - - log_ipv4acd_errno(acd, errno, "Failed to read ARP packet: %m"); - goto fail; - } - if ((size_t) n != sizeof(struct ether_arp)) { - log_ipv4acd(acd, "Ignoring too short ARP packet."); - return 0; - } - - switch (acd->state) { - - case IPV4ACD_STATE_ANNOUNCING: - case IPV4ACD_STATE_RUNNING: - - if (ipv4acd_arp_conflict(acd, &packet)) { - usec_t ts; - - assert_se(sd_event_now(acd->event, clock_boottime_or_monotonic(), &ts) >= 0); - - /* Defend address */ - if (ts > acd->defend_window) { - acd->defend_window = ts + DEFEND_INTERVAL_USEC; - r = arp_send_announcement(acd->fd, acd->ifindex, acd->address, &acd->mac_addr); - if (r < 0) { - log_ipv4acd_errno(acd, r, "Failed to send ARP announcement: %m"); - goto fail; - } else - log_ipv4acd(acd, "DEFEND"); - - } else - ipv4acd_on_conflict(acd); - } - break; - - case IPV4ACD_STATE_WAITING_PROBE: - case IPV4ACD_STATE_PROBING: - case IPV4ACD_STATE_WAITING_ANNOUNCE: - /* BPF ensures this packet indicates a conflict */ - ipv4acd_on_conflict(acd); - break; - - default: - assert_not_reached("Invalid state."); - } - - return 0; - -fail: - sd_ipv4acd_stop(acd); - return 0; -} - -int sd_ipv4acd_set_ifindex(sd_ipv4acd *acd, int ifindex) { - assert_return(acd, -EINVAL); - assert_return(ifindex > 0, -EINVAL); - assert_return(acd->state == IPV4ACD_STATE_INIT, -EBUSY); - - acd->ifindex = ifindex; - - return 0; -} - -int sd_ipv4acd_set_mac(sd_ipv4acd *acd, const struct ether_addr *addr) { - assert_return(acd, -EINVAL); - assert_return(addr, -EINVAL); - assert_return(acd->state == IPV4ACD_STATE_INIT, -EBUSY); - - acd->mac_addr = *addr; - - return 0; -} - -int sd_ipv4acd_detach_event(sd_ipv4acd *acd) { - assert_return(acd, -EINVAL); - - acd->event = sd_event_unref(acd->event); - - return 0; -} - -int sd_ipv4acd_attach_event(sd_ipv4acd *acd, sd_event *event, int64_t priority) { - int r; - - assert_return(acd, -EINVAL); - assert_return(!acd->event, -EBUSY); - - if (event) - acd->event = sd_event_ref(event); - else { - r = sd_event_default(&acd->event); - if (r < 0) - return r; - } - - acd->event_priority = priority; - - return 0; -} - -int sd_ipv4acd_set_callback(sd_ipv4acd *acd, sd_ipv4acd_callback_t cb, void *userdata) { - assert_return(acd, -EINVAL); - - acd->callback = cb; - acd->userdata = userdata; - - return 0; -} - -int sd_ipv4acd_set_address(sd_ipv4acd *acd, const struct in_addr *address) { - assert_return(acd, -EINVAL); - assert_return(address, -EINVAL); - assert_return(acd->state == IPV4ACD_STATE_INIT, -EBUSY); - - acd->address = address->s_addr; - - return 0; -} - -int sd_ipv4acd_is_running(sd_ipv4acd *acd) { - assert_return(acd, false); - - return acd->state != IPV4ACD_STATE_INIT; -} - -int sd_ipv4acd_start(sd_ipv4acd *acd) { - int r; - - assert_return(acd, -EINVAL); - assert_return(acd->event, -EINVAL); - assert_return(acd->ifindex > 0, -EINVAL); - assert_return(acd->address != 0, -EINVAL); - assert_return(!ether_addr_is_null(&acd->mac_addr), -EINVAL); - assert_return(acd->state == IPV4ACD_STATE_INIT, -EBUSY); - - r = arp_network_bind_raw_socket(acd->ifindex, acd->address, &acd->mac_addr); - if (r < 0) - return r; - - safe_close(acd->fd); - acd->fd = r; - acd->defend_window = 0; - acd->n_conflict = 0; - - r = sd_event_add_io(acd->event, &acd->receive_message_event_source, acd->fd, EPOLLIN, ipv4acd_on_packet, acd); - if (r < 0) - goto fail; - - r = sd_event_source_set_priority(acd->receive_message_event_source, acd->event_priority); - if (r < 0) - goto fail; - - (void) sd_event_source_set_description(acd->receive_message_event_source, "ipv4acd-receive-message"); - - r = ipv4acd_set_next_wakeup(acd, 0, 0); - if (r < 0) - goto fail; - - ipv4acd_set_state(acd, IPV4ACD_STATE_STARTED, true); - return 0; - -fail: - ipv4acd_reset(acd); - return r; -} |