+++ /dev/null
-/***
- This file is part of systemd.
-
- Copyright (C) 2014 Axis Communications AB. 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 <stdlib.h>
-#include <errno.h>
-#include <string.h>
-#include <stdio.h>
-#include <arpa/inet.h>
-
-#include "util.h"
-#include "siphash24.h"
-#include "list.h"
-#include "refcnt.h"
-
-#include "ipv4ll-internal.h"
-#include "sd-ipv4ll.h"
-
-/* Constants from the RFC */
-#define PROBE_WAIT 1
-#define PROBE_NUM 3
-#define PROBE_MIN 1
-#define PROBE_MAX 2
-#define ANNOUNCE_WAIT 2
-#define ANNOUNCE_NUM 2
-#define ANNOUNCE_INTERVAL 2
-#define MAX_CONFLICTS 10
-#define RATE_LIMIT_INTERVAL 60
-#define DEFEND_INTERVAL 10
-
-#define IPV4LL_NETWORK 0xA9FE0000L
-#define IPV4LL_NETMASK 0xFFFF0000L
-
-typedef enum IPv4LLTrigger{
- IPV4LL_TRIGGER_NULL,
- IPV4LL_TRIGGER_PACKET,
- IPV4LL_TRIGGER_TIMEOUT,
- _IPV4LL_TRIGGER_MAX,
- _IPV4LL_TRIGGER_INVALID = -1
-} IPv4LLTrigger;
-
-typedef enum IPv4LLState {
- IPV4LL_STATE_INIT,
- IPV4LL_STATE_WAITING_PROBE,
- IPV4LL_STATE_PROBING,
- IPV4LL_STATE_WAITING_ANNOUNCE,
- IPV4LL_STATE_ANNOUNCING,
- IPV4LL_STATE_RUNNING,
- IPV4LL_STATE_STOPPED,
- _IPV4LL_STATE_MAX,
- _IPV4LL_STATE_INVALID = -1
-} IPv4LLState;
-
-struct sd_ipv4ll {
- RefCount n_ref;
-
- IPv4LLState state;
- int index;
- int fd;
- union sockaddr_union link;
- int iteration;
- int conflict;
- sd_event_source *receive_message;
- sd_event_source *timer;
- usec_t next_wakeup;
- usec_t defend_window;
- int next_wakeup_valid;
- be32_t address;
- struct random_data *random_data;
- char *random_data_state;
- /* External */
- be32_t claimed_address;
- struct ether_addr mac_addr;
- sd_event *event;
- int event_priority;
- sd_ipv4ll_cb_t cb;
- void* userdata;
-};
-
-static void ipv4ll_run_state_machine(sd_ipv4ll *ll, IPv4LLTrigger trigger, void *trigger_data);
-
-static void ipv4ll_set_state(sd_ipv4ll *ll, IPv4LLState st, int reset_counter) {
-
- assert(ll);
- assert(st < _IPV4LL_STATE_MAX);
-
- if (st == ll->state && !reset_counter) {
- ll->iteration++;
- } else {
- ll->state = st;
- ll->iteration = 0;
- }
-}
-
-static sd_ipv4ll *ipv4ll_client_notify(sd_ipv4ll *ll, int event) {
- assert(ll);
-
- if (ll->cb) {
- ll = sd_ipv4ll_ref(ll);
- ll->cb(ll, event, ll->userdata);
- ll = sd_ipv4ll_unref(ll);
- }
-
- return ll;
-}
-
-static sd_ipv4ll *ipv4ll_stop(sd_ipv4ll *ll, int event) {
- assert(ll);
-
- ll->receive_message = sd_event_source_unref(ll->receive_message);
- ll->fd = safe_close(ll->fd);
-
- ll->timer = sd_event_source_unref(ll->timer);
-
- log_ipv4ll(ll, "STOPPED");
-
- ll = ipv4ll_client_notify(ll, event);
-
- if (ll) {
- ll->claimed_address = 0;
- ipv4ll_set_state (ll, IPV4LL_STATE_INIT, 1);
- }
-
- return ll;
-}
-
-static int ipv4ll_pick_address(sd_ipv4ll *ll, be32_t *address) {
- be32_t addr;
- int r;
- int32_t random;
-
- assert(ll);
- assert(address);
- assert(ll->random_data);
-
- do {
- r = random_r(ll->random_data, &random);
- if (r < 0)
- return r;
- addr = htonl((random & 0x0000FFFF) | IPV4LL_NETWORK);
- } while (addr == ll->address ||
- (ntohl(addr) & IPV4LL_NETMASK) != IPV4LL_NETWORK ||
- (ntohl(addr) & 0x0000FF00) == 0x0000 ||
- (ntohl(addr) & 0x0000FF00) == 0xFF00);
-
- *address = addr;
- return 0;
-}
-
-static int ipv4ll_timer(sd_event_source *s, uint64_t usec, void *userdata) {
- sd_ipv4ll *ll = (sd_ipv4ll*)userdata;
-
- assert(ll);
-
- ll->next_wakeup_valid = 0;
- ipv4ll_run_state_machine(ll, IPV4LL_TRIGGER_TIMEOUT, NULL);
-
- return 0;
-}
-
-static void ipv4ll_set_next_wakeup(sd_ipv4ll *ll, int sec, int random_sec) {
- usec_t next_timeout = 0;
- usec_t time_now = 0;
-
- assert(sec >= 0);
- assert(random_sec >= 0);
- assert(ll);
-
- next_timeout = sec * USEC_PER_SEC;
-
- if (random_sec)
- next_timeout += random_u32() % (random_sec * USEC_PER_SEC);
-
- if (sd_event_now(ll->event, clock_boottime_or_monotonic(), &time_now) < 0)
- time_now = now(clock_boottime_or_monotonic());
-
- ll->next_wakeup = time_now + next_timeout;
- ll->next_wakeup_valid = 1;
-}
-
-static bool ipv4ll_arp_conflict (sd_ipv4ll *ll, struct ether_arp *arp) {
- assert(ll);
- assert(arp);
-
- if (memcmp(arp->arp_spa, &ll->address, sizeof(ll->address)) == 0 &&
- memcmp(arp->arp_sha, &ll->mac_addr, ETH_ALEN) != 0)
- return true;
-
- return false;
-}
-
-static bool ipv4ll_arp_probe_conflict (sd_ipv4ll *ll, struct ether_arp *arp) {
- assert(ll);
- assert(arp);
-
- if (ipv4ll_arp_conflict(ll, arp))
- return true;
-
- if (memcmp(arp->arp_tpa, &ll->address, sizeof(ll->address)) == 0 &&
- memcmp(arp->arp_sha, &ll->mac_addr, ETH_ALEN))
- return true;
-
- return false;
-}
-
-static void ipv4ll_run_state_machine(sd_ipv4ll *ll, IPv4LLTrigger trigger, void *trigger_data) {
- struct ether_arp out_packet;
- int out_packet_ready = 0;
- int r = 0;
-
- assert(ll);
- assert(trigger < _IPV4LL_TRIGGER_MAX);
-
- if (ll->state == IPV4LL_STATE_INIT) {
-
- log_ipv4ll(ll, "PROBE");
- ipv4ll_set_state(ll, IPV4LL_STATE_WAITING_PROBE, 1);
- ipv4ll_set_next_wakeup(ll, 0, PROBE_WAIT);
-
- } else if ((ll->state == IPV4LL_STATE_WAITING_PROBE && trigger == IPV4LL_TRIGGER_TIMEOUT) ||
- (ll->state == IPV4LL_STATE_PROBING && trigger == IPV4LL_TRIGGER_TIMEOUT && ll->iteration < PROBE_NUM-2)) {
-
- /* Send a probe */
- arp_packet_probe(&out_packet, ll->address, &ll->mac_addr);
- out_packet_ready = 1;
- ipv4ll_set_state(ll, IPV4LL_STATE_PROBING, 0);
-
- ipv4ll_set_next_wakeup(ll, PROBE_MIN, (PROBE_MAX-PROBE_MIN));
-
- } else if (ll->state == IPV4LL_STATE_PROBING && trigger == IPV4LL_TRIGGER_TIMEOUT && ll->iteration >= PROBE_NUM-2) {
-
- /* Send the last probe */
- arp_packet_probe(&out_packet, ll->address, &ll->mac_addr);
- out_packet_ready = 1;
- ipv4ll_set_state(ll, IPV4LL_STATE_WAITING_ANNOUNCE, 1);
-
- ipv4ll_set_next_wakeup(ll, ANNOUNCE_WAIT, 0);
-
- } else if ((ll->state == IPV4LL_STATE_WAITING_ANNOUNCE && trigger == IPV4LL_TRIGGER_TIMEOUT) ||
- (ll->state == IPV4LL_STATE_ANNOUNCING && trigger == IPV4LL_TRIGGER_TIMEOUT && ll->iteration < ANNOUNCE_NUM-1)) {
-
- /* Send announcement packet */
- arp_packet_announcement(&out_packet, ll->address, &ll->mac_addr);
- out_packet_ready = 1;
- ipv4ll_set_state(ll, IPV4LL_STATE_ANNOUNCING, 0);
-
- ipv4ll_set_next_wakeup(ll, ANNOUNCE_INTERVAL, 0);
-
- if (ll->iteration == 0) {
- log_ipv4ll(ll, "ANNOUNCE");
- ll->claimed_address = ll->address;
- ll = ipv4ll_client_notify(ll, IPV4LL_EVENT_BIND);
- if (!ll || ll->state == IPV4LL_STATE_STOPPED)
- goto out;
-
- ll->conflict = 0;
- }
-
- } else if ((ll->state == IPV4LL_STATE_ANNOUNCING && trigger == IPV4LL_TRIGGER_TIMEOUT &&
- ll->iteration >= ANNOUNCE_NUM-1)) {
-
- ipv4ll_set_state(ll, IPV4LL_STATE_RUNNING, 0);
- ll->next_wakeup_valid = 0;
-
- } else if (trigger == IPV4LL_TRIGGER_PACKET) {
-
- int conflicted = 0;
- usec_t time_now;
- struct ether_arp* in_packet = (struct ether_arp*)trigger_data;
-
- assert(in_packet);
-
- if (IN_SET(ll->state, IPV4LL_STATE_ANNOUNCING, IPV4LL_STATE_RUNNING)) {
-
- if (ipv4ll_arp_conflict(ll, in_packet)) {
-
- r = sd_event_now(ll->event, clock_boottime_or_monotonic(), &time_now);
- if (r < 0)
- goto out;
-
- /* Defend address */
- if (time_now > ll->defend_window) {
- ll->defend_window = time_now + DEFEND_INTERVAL * USEC_PER_SEC;
- arp_packet_announcement(&out_packet, ll->address, &ll->mac_addr);
- out_packet_ready = 1;
- } else
- conflicted = 1;
- }
-
- } else if (IN_SET(ll->state, IPV4LL_STATE_WAITING_PROBE,
- IPV4LL_STATE_PROBING,
- IPV4LL_STATE_WAITING_ANNOUNCE)) {
-
- conflicted = ipv4ll_arp_probe_conflict(ll, in_packet);
- }
-
- if (conflicted) {
- log_ipv4ll(ll, "CONFLICT");
- ll = ipv4ll_client_notify(ll, IPV4LL_EVENT_CONFLICT);
- if (!ll || ll->state == IPV4LL_STATE_STOPPED)
- goto out;
-
- ll->claimed_address = 0;
-
- /* Pick a new address */
- r = ipv4ll_pick_address(ll, &ll->address);
- if (r < 0)
- goto out;
- ll->conflict++;
- ll->defend_window = 0;
- ipv4ll_set_state(ll, IPV4LL_STATE_WAITING_PROBE, 1);
-
- if (ll->conflict >= MAX_CONFLICTS) {
- log_ipv4ll(ll, "MAX_CONFLICTS");
- ipv4ll_set_next_wakeup(ll, RATE_LIMIT_INTERVAL, PROBE_WAIT);
- } else
- ipv4ll_set_next_wakeup(ll, 0, PROBE_WAIT);
-
- }
- }
-
- if (out_packet_ready) {
- r = arp_network_send_raw_socket(ll->fd, &ll->link, &out_packet);
- if (r < 0) {
- log_ipv4ll(ll, "failed to send arp packet out");
- goto out;
- }
- }
-
- if (ll->next_wakeup_valid) {
- ll->timer = sd_event_source_unref(ll->timer);
- r = sd_event_add_time(ll->event, &ll->timer, clock_boottime_or_monotonic(),
- ll->next_wakeup, 0, ipv4ll_timer, ll);
- if (r < 0)
- goto out;
-
- r = sd_event_source_set_priority(ll->timer, ll->event_priority);
- if (r < 0)
- goto out;
-
- r = sd_event_source_set_description(ll->timer, "ipv4ll-timer");
- if (r < 0)
- goto out;
- }
-
-out:
- if (r < 0 && ll)
- ipv4ll_stop(ll, r);
-}
-
-static int ipv4ll_receive_message(sd_event_source *s, int fd,
- uint32_t revents, void *userdata) {
- int r;
- struct ether_arp arp;
- sd_ipv4ll *ll = (sd_ipv4ll*)userdata;
-
- assert(ll);
-
- r = read(fd, &arp, sizeof(struct ether_arp));
- if (r < (int) sizeof(struct ether_arp))
- return 0;
-
- r = arp_packet_verify_headers(&arp);
- if (r < 0)
- return 0;
-
- ipv4ll_run_state_machine(ll, IPV4LL_TRIGGER_PACKET, &arp);
-
- return 0;
-}
-
-int sd_ipv4ll_set_index(sd_ipv4ll *ll, int interface_index) {
- assert_return(ll, -EINVAL);
- assert_return(interface_index > 0, -EINVAL);
- assert_return(IN_SET(ll->state, IPV4LL_STATE_INIT,
- IPV4LL_STATE_STOPPED), -EBUSY);
-
- ll->index = interface_index;
-
- return 0;
-}
-
-int sd_ipv4ll_set_mac(sd_ipv4ll *ll, const struct ether_addr *addr) {
- bool need_restart = false;
-
- assert_return(ll, -EINVAL);
- assert_return(addr, -EINVAL);
-
- if (memcmp(&ll->mac_addr, addr, ETH_ALEN) == 0)
- return 0;
-
- if (!IN_SET(ll->state, IPV4LL_STATE_INIT, IPV4LL_STATE_STOPPED)) {
- log_ipv4ll(ll, "Changing MAC address on running IPv4LL "
- "client, restarting");
- ll = ipv4ll_stop(ll, IPV4LL_EVENT_STOP);
- need_restart = true;
- }
-
- if (!ll)
- return 0;
-
- memcpy(&ll->mac_addr, addr, ETH_ALEN);
-
- if (need_restart)
- sd_ipv4ll_start(ll);
-
- return 0;
-}
-
-int sd_ipv4ll_detach_event(sd_ipv4ll *ll) {
- assert_return(ll, -EINVAL);
-
- ll->event = sd_event_unref(ll->event);
-
- return 0;
-}
-
-int sd_ipv4ll_attach_event(sd_ipv4ll *ll, sd_event *event, int priority) {
- int r;
-
- assert_return(ll, -EINVAL);
- assert_return(!ll->event, -EBUSY);
-
- if (event)
- ll->event = sd_event_ref(event);
- else {
- r = sd_event_default(&ll->event);
- if (r < 0) {
- ipv4ll_stop(ll, IPV4LL_EVENT_STOP);
- return r;
- }
- }
-
- ll->event_priority = priority;
-
- return 0;
-}
-
-int sd_ipv4ll_set_callback(sd_ipv4ll *ll, sd_ipv4ll_cb_t cb, void *userdata) {
- assert_return(ll, -EINVAL);
-
- ll->cb = cb;
- ll->userdata = userdata;
-
- return 0;
-}
-
-int sd_ipv4ll_get_address(sd_ipv4ll *ll, struct in_addr *address){
- assert_return(ll, -EINVAL);
- assert_return(address, -EINVAL);
-
- if (ll->claimed_address == 0) {
- return -ENOENT;
- }
-
- address->s_addr = ll->claimed_address;
- return 0;
-}
-
-int sd_ipv4ll_set_address_seed (sd_ipv4ll *ll, uint8_t seed[8]) {
- unsigned int entropy;
- int r;
-
- assert_return(ll, -EINVAL);
- assert_return(seed, -EINVAL);
-
- entropy = *seed;
-
- free(ll->random_data);
- free(ll->random_data_state);
-
- ll->random_data = new0(struct random_data, 1);
- ll->random_data_state = new0(char, 128);
-
- if (!ll->random_data || !ll->random_data_state) {
- r = -ENOMEM;
- goto error;
- }
-
- r = initstate_r((unsigned int)entropy, ll->random_data_state, 128, ll->random_data);
- if (r < 0)
- goto error;
-
-error:
- if (r < 0){
- free(ll->random_data);
- free(ll->random_data_state);
- ll->random_data = NULL;
- ll->random_data_state = NULL;
- }
- return r;
-}
-
-bool sd_ipv4ll_is_running(sd_ipv4ll *ll) {
- assert_return(ll, -EINVAL);
-
- return !IN_SET(ll->state, IPV4LL_STATE_INIT, IPV4LL_STATE_STOPPED);
-}
-
-#define HASH_KEY SD_ID128_MAKE(df,04,22,98,3f,ad,14,52,f9,87,2e,d1,9c,70,e2,f2)
-
-int sd_ipv4ll_start (sd_ipv4ll *ll) {
- int r;
-
- assert_return(ll, -EINVAL);
- assert_return(ll->event, -EINVAL);
- assert_return(ll->index > 0, -EINVAL);
- assert_return(IN_SET(ll->state, IPV4LL_STATE_INIT,
- IPV4LL_STATE_STOPPED), -EBUSY);
-
- ll->state = IPV4LL_STATE_INIT;
-
- r = arp_network_bind_raw_socket(ll->index, &ll->link);
-
- if (r < 0)
- goto out;
-
- ll->fd = r;
- ll->conflict = 0;
- ll->defend_window = 0;
- ll->claimed_address = 0;
-
- if (!ll->random_data) {
- uint8_t seed[8];
-
- /* Fallback to mac */
- siphash24(seed, &ll->mac_addr.ether_addr_octet,
- ETH_ALEN, HASH_KEY.bytes);
-
- r = sd_ipv4ll_set_address_seed(ll, seed);
- if (r < 0)
- goto out;
- }
-
- if (ll->address == 0) {
- r = ipv4ll_pick_address(ll, &ll->address);
- if (r < 0)
- goto out;
- }
-
- ipv4ll_set_state (ll, IPV4LL_STATE_INIT, 1);
-
- r = sd_event_add_io(ll->event, &ll->receive_message, ll->fd,
- EPOLLIN, ipv4ll_receive_message, ll);
- if (r < 0)
- goto out;
-
- r = sd_event_source_set_priority(ll->receive_message, ll->event_priority);
- if (r < 0)
- goto out;
-
- r = sd_event_source_set_description(ll->receive_message, "ipv4ll-receive-message");
- if (r < 0)
- goto out;
-
- r = sd_event_add_time(ll->event,
- &ll->timer,
- clock_boottime_or_monotonic(),
- now(clock_boottime_or_monotonic()), 0,
- ipv4ll_timer, ll);
-
- if (r < 0)
- goto out;
-
- r = sd_event_source_set_priority(ll->timer, ll->event_priority);
- if (r < 0)
- goto out;
-
- r = sd_event_source_set_description(ll->timer, "ipv4ll-timer");
-out:
- if (r < 0)
- ipv4ll_stop(ll, IPV4LL_EVENT_STOP);
-
- return 0;
-}
-
-int sd_ipv4ll_stop(sd_ipv4ll *ll) {
- ipv4ll_stop(ll, IPV4LL_EVENT_STOP);
- if (ll)
- ipv4ll_set_state(ll, IPV4LL_STATE_STOPPED, 1);
-
- return 0;
-}
-
-sd_ipv4ll *sd_ipv4ll_ref(sd_ipv4ll *ll) {
- if (ll)
- assert_se(REFCNT_INC(ll->n_ref) >= 2);
-
- return ll;
-}
-
-sd_ipv4ll *sd_ipv4ll_unref(sd_ipv4ll *ll) {
- if (ll && REFCNT_DEC(ll->n_ref) == 0) {
- ll->receive_message =
- sd_event_source_unref(ll->receive_message);
- ll->fd = safe_close(ll->fd);
-
- ll->timer = sd_event_source_unref(ll->timer);
-
- sd_ipv4ll_detach_event(ll);
-
- free(ll->random_data);
- free(ll->random_data_state);
- free(ll);
-
- return NULL;
- }
-
- return ll;
-}
-
-DEFINE_TRIVIAL_CLEANUP_FUNC(sd_ipv4ll*, sd_ipv4ll_unref);
-#define _cleanup_ipv4ll_free_ _cleanup_(sd_ipv4ll_unrefp)
-
-int sd_ipv4ll_new(sd_ipv4ll **ret) {
- _cleanup_ipv4ll_free_ sd_ipv4ll *ll = NULL;
-
- assert_return(ret, -EINVAL);
-
- ll = new0(sd_ipv4ll, 1);
- if (!ll)
- return -ENOMEM;
-
- ll->n_ref = REFCNT_INIT;
- ll->state = IPV4LL_STATE_INIT;
- ll->index = -1;
- ll->fd = -1;
-
- *ret = ll;
- ll = NULL;
-
- return 0;
-}
~ianmdlvl / elogind.git / blobdiff