diff options
Diffstat (limited to 'src/libnm-systemd-core/src/libsystemd-network/sd-ipv4acd.c')
| -rw-r--r-- | src/libnm-systemd-core/src/libsystemd-network/sd-ipv4acd.c | 616 |
1 files changed, 0 insertions, 616 deletions
diff --git a/src/libnm-systemd-core/src/libsystemd-network/sd-ipv4acd.c b/src/libnm-systemd-core/src/libsystemd-network/sd-ipv4acd.c deleted file mode 100644 index f0612ed5..00000000 --- a/src/libnm-systemd-core/src/libsystemd-network/sd-ipv4acd.c +++ /dev/null @@ -1,616 +0,0 @@ -/* SPDX-License-Identifier: LGPL-2.1-or-later */ -/*** - Copyright © 2014 Axis Communications AB. All rights reserved. -***/ - -#include "nm-sd-adapt-core.h" - -#include <arpa/inet.h> -#include <errno.h> -#include <netinet/if_ether.h> -#include <stdio.h> -#include <stdlib.h> - -#include "sd-ipv4acd.h" - -#include "alloc-util.h" -#include "arp-util.h" -#include "ether-addr-util.h" -#include "event-util.h" -#include "fd-util.h" -#include "in-addr-util.h" -#include "memory-util.h" -#include "network-common.h" -#include "random-util.h" -#include "siphash24.h" -#include "string-table.h" -#include "string-util.h" -#include "time-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 = -EINVAL, -} IPv4ACDState; - -struct sd_ipv4acd { - unsigned n_ref; - - IPv4ACDState state; - int ifindex; - int fd; - - char *ifname; - unsigned n_iteration; - unsigned n_conflict; - - sd_event_source *receive_message_event_source; - sd_event_source *timer_event_source; - - usec_t defend_window; - struct in_addr address; - - /* External */ - struct ether_addr mac_addr; - - sd_event *event; - int event_priority; - sd_ipv4acd_callback_t callback; - void *userdata; - sd_ipv4acd_check_mac_callback_t check_mac_callback; - void *check_mac_userdata; -}; - -#define log_ipv4acd_errno(acd, error, fmt, ...) \ - log_interface_prefix_full_errno( \ - "IPv4ACD: ", \ - sd_ipv4acd, acd, \ - error, fmt, ##__VA_ARGS__) -#define log_ipv4acd(acd, fmt, ...) \ - log_interface_prefix_full_errno_zerook( \ - "IPv4ACD: ", \ - sd_ipv4acd, acd, \ - 0, fmt, ##__VA_ARGS__) - -static const char * const ipv4acd_state_table[_IPV4ACD_STATE_MAX] = { - [IPV4ACD_STATE_INIT] = "init", - [IPV4ACD_STATE_STARTED] = "started", - [IPV4ACD_STATE_WAITING_PROBE] = "waiting-probe", - [IPV4ACD_STATE_PROBING] = "probing", - [IPV4ACD_STATE_WAITING_ANNOUNCE] = "waiting-announce", - [IPV4ACD_STATE_ANNOUNCING] = "announcing", - [IPV4ACD_STATE_RUNNING] = "running", -}; - -DEFINE_PRIVATE_STRING_TABLE_LOOKUP_TO_STRING(ipv4acd_state, IPv4ACDState); - -static void ipv4acd_set_state(sd_ipv4acd *acd, IPv4ACDState st, bool reset_counter) { - assert(acd); - assert(st < _IPV4ACD_STATE_MAX); - - if (st != acd->state) - log_ipv4acd(acd, "%s -> %s", ipv4acd_state_to_string(acd->state), ipv4acd_state_to_string(st)); - - 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); - - (void) event_source_disable(acd->timer_event_source); - acd->receive_message_event_source = sd_event_source_disable_unref(acd->receive_message_event_source); - - acd->fd = safe_close(acd->fd); - - ipv4acd_set_state(acd, IPV4ACD_STATE_INIT, true); -} - -static sd_ipv4acd *ipv4acd_free(sd_ipv4acd *acd) { - assert(acd); - - ipv4acd_reset(acd); - sd_event_source_unref(acd->timer_event_source); - sd_ipv4acd_detach_event(acd); - free(acd->ifname); - return mfree(acd); -} - -DEFINE_TRIVIAL_REF_UNREF_FUNC(sd_ipv4acd, sd_ipv4acd, ipv4acd_free); - -int sd_ipv4acd_new(sd_ipv4acd **ret) { - _cleanup_(sd_ipv4acd_unrefp) sd_ipv4acd *acd = NULL; - - assert_return(ret, -EINVAL); - - acd = new(sd_ipv4acd, 1); - if (!acd) - return -ENOMEM; - - *acd = (sd_ipv4acd) { - .n_ref = 1, - .state = IPV4ACD_STATE_INIT, - .ifindex = -1, - .fd = -1, - }; - - *ret = TAKE_PTR(acd); - - 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) { - IPv4ACDState old_state; - - if (!acd) - return 0; - - old_state = acd->state; - - ipv4acd_reset(acd); - - if (old_state == IPV4ACD_STATE_INIT) - return 0; - - 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) { - usec_t next_timeout, time_now; - - 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); - - return event_reset_time(acd->event, &acd->timer_event_source, - clock_boottime_or_monotonic(), - time_now + next_timeout, 0, - ipv4acd_on_timeout, acd, - acd->event_priority, "ipv4acd-timer", true); -} - -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: - acd->defend_window = 0; - - ipv4acd_set_state(acd, IPV4ACD_STATE_WAITING_PROBE, true); - - if (acd->n_conflict >= MAX_CONFLICTS) { - log_ipv4acd(acd, "Max conflicts reached, delaying by %s", - FORMAT_TIMESPAN(RATE_LIMIT_INTERVAL_USEC, 0)); - r = ipv4acd_set_next_wakeup(acd, RATE_LIMIT_INTERVAL_USEC, PROBE_WAIT_USEC); - } 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; - } - - log_ipv4acd(acd, "Probing "IPV4_ADDRESS_FMT_STR, IPV4_ADDRESS_FMT_VAL(acd->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; - } - - _fallthrough_; - 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; - } - - log_ipv4acd(acd, "Announcing "IPV4_ADDRESS_FMT_STR, IPV4_ADDRESS_FMT_VAL(acd->address)); - - 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(); - } - - return 0; - -fail: - sd_ipv4acd_stop(acd); - return 0; -} - -static bool ipv4acd_arp_conflict(sd_ipv4acd *acd, const struct ether_arp *arp, bool announced) { - assert(acd); - assert(arp); - - /* RFC 5227 section 2.1.1. - * "the host receives any ARP packet (Request *or* Reply) on the interface where the probe is - * being performed, where the packet's 'sender IP address' is the address being probed for, - * then the host MUST treat this address as being in use by some other host" */ - if (memcmp(arp->arp_spa, &acd->address, sizeof(struct in_addr)) == 0) - return true; - - if (announced) - /* the TPA matched instead of SPA, this is not a conflict */ - return false; - - /* "any ARP Probe where the packet's 'target IP address' is the address being probed for, and - * the packet's 'sender hardware address' is not the hardware address of any of the host's - * interfaces, then the host SHOULD similarly treat this as an address conflict" */ - if (arp->ea_hdr.ar_op != htobe16(ARPOP_REQUEST)) - return false; /* not ARP Request, ignoring. */ - if (memeqzero(arp->arp_spa, sizeof(struct in_addr)) == 0) - return false; /* not ARP Probe, ignoring. */ - if (memcmp(arp->arp_tpa, &acd->address, sizeof(struct in_addr)) != 0) - return false; /* target IP address does not match, BPF code is broken? */ - - if (acd->check_mac_callback && - acd->check_mac_callback(acd, (const struct ether_addr*) arp->arp_sha, acd->check_mac_userdata) > 0) - /* sender hardware is one of the host's interfaces, ignoring. */ - return true; - - return true; /* conflict! */ -} - -static void ipv4acd_on_conflict(sd_ipv4acd *acd) { - assert(acd); - - acd->n_conflict++; - - log_ipv4acd(acd, "Conflict on "IPV4_ADDRESS_FMT_STR" (%u)", IPV4_ADDRESS_FMT_VAL(acd->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 (IN_SET(errno, EAGAIN, 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, true)) { - 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; - } - - log_ipv4acd(acd, "Defending "IPV4_ADDRESS_FMT_STR, IPV4_ADDRESS_FMT_VAL(acd->address)); - - } else - ipv4acd_on_conflict(acd); - } - break; - - case IPV4ACD_STATE_WAITING_PROBE: - case IPV4ACD_STATE_PROBING: - case IPV4ACD_STATE_WAITING_ANNOUNCE: - if (ipv4acd_arp_conflict(acd, &packet, false)) - ipv4acd_on_conflict(acd); - break; - - default: - assert_not_reached(); - } - - 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_get_ifindex(sd_ipv4acd *acd) { - if (!acd) - return -EINVAL; - - return acd->ifindex; -} - -int sd_ipv4acd_set_ifname(sd_ipv4acd *acd, const char *ifname) { - assert_return(acd, -EINVAL); - assert_return(ifname, -EINVAL); - - if (!ifname_valid_full(ifname, IFNAME_VALID_ALTERNATIVE)) - return -EINVAL; - - return free_and_strdup(&acd->ifname, ifname); -} - -int sd_ipv4acd_get_ifname(sd_ipv4acd *acd, const char **ret) { - int r; - - assert_return(acd, -EINVAL); - - r = get_ifname(acd->ifindex, &acd->ifname); - if (r < 0) - return r; - - if (ret) - *ret = acd->ifname; - - return 0; -} - -int sd_ipv4acd_set_mac(sd_ipv4acd *acd, const struct ether_addr *addr) { - int r; - - assert_return(acd, -EINVAL); - assert_return(addr, -EINVAL); - assert_return(!ether_addr_is_null(addr), -EINVAL); - - acd->mac_addr = *addr; - - if (!sd_ipv4acd_is_running(acd)) - return 0; - - assert(acd->fd >= 0); - r = arp_update_filter(acd->fd, &acd->address, &acd->mac_addr); - if (r < 0) { - ipv4acd_reset(acd); - return r; - } - - 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_check_mac_callback(sd_ipv4acd *acd, sd_ipv4acd_check_mac_callback_t cb, void *userdata) { - assert_return(acd, -EINVAL); - - acd->check_mac_callback = cb; - acd->check_mac_userdata = userdata; - return 0; -} - -int sd_ipv4acd_set_address(sd_ipv4acd *acd, const struct in_addr *address) { - int r; - - assert_return(acd, -EINVAL); - assert_return(address, -EINVAL); - assert_return(in4_addr_is_set(address), -EINVAL); - - if (in4_addr_equal(&acd->address, address)) - return 0; - - acd->address = *address; - - if (!sd_ipv4acd_is_running(acd)) - return 0; - - assert(acd->fd >= 0); - r = arp_update_filter(acd->fd, &acd->address, &acd->mac_addr); - if (r < 0) - goto fail; - - 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; -} - -int sd_ipv4acd_get_address(sd_ipv4acd *acd, struct in_addr *address) { - assert_return(acd, -EINVAL); - assert_return(address, -EINVAL); - - *address = acd->address; - - 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, bool reset_conflicts) { - int r; - - assert_return(acd, -EINVAL); - assert_return(acd->event, -EINVAL); - assert_return(acd->ifindex > 0, -EINVAL); - assert_return(in4_addr_is_set(&acd->address), -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; - - CLOSE_AND_REPLACE(acd->fd, r); - - if (reset_conflicts) - 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; -} |