+++ /dev/null
-/***
- 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 "refcnt.h"
-#include "async.h"
-
-#include "dhcp6-internal.h"
-#include "sd-icmp6-nd.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 {
- RefCount n_ref;
-
- LIST_FIELDS(ICMP6Prefix, prefixes);
-
- uint8_t len;
- sd_event_source *timeout_valid;
- struct in6_addr addr;
-};
-
-struct sd_icmp6_nd {
- RefCount 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 && REFCNT_DEC(prefix->n_ref) <= 0) {
- 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 = REFCNT_INIT;
- 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) {
- assert (nd);
-
- assert_se(REFCNT_INC(nd->n_ref) >= 2);
-
- 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) {
- if (nd && REFCNT_DEC(nd->n_ref) == 0) {
- ICMP6Prefix *prefix, *p;
-
- 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 = REFCNT_INIT;
-
- 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_ADDRESS_FORMAT_STR"/%d",
- SD_ICMP6_ADDRESS_FORMAT_VAL(prefix->addr),
- prefix->len);
-
- LIST_REMOVE(prefixes, nd->prefixes, prefix);
-
- nd->expired_prefix = prefix;
- icmp6_nd_notify(nd,
- ICMP6_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_ADDRESS_FORMAT_STR"/%d lifetime %d expires in %s",
- SD_ICMP6_ADDRESS_FORMAT_VAL(prefix->addr),
- prefix->len, lifetime,
- format_timespan(time_string, FORMAT_TIMESPAN_MAX,
- lifetime * USEC_PER_SEC, 0));
-
- 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_ADDRESS_FORMAT_STR"/%d lifetime %d expires in %s",
- SD_ICMP6_ADDRESS_FORMAT_VAL(prefix->addr),
- prefix->len, lifetime,
- format_timespan(time_string, FORMAT_TIMESPAN_MAX,
- lifetime * USEC_PER_SEC, 0));
- }
-
- 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 = ICMP6_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 = ICMP6_EVENT_ROUTER_ADVERTISMENT_OTHER;
-
- if (ra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED)
- event = ICMP6_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 != ICMP6_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, ICMP6_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;
-}
~ianmdlvl / elogind.git / blobdiff