diff options
Diffstat (limited to 'src/libsystemd-network/sd-icmp6-nd.c')
| -rw-r--r-- | src/libsystemd-network/sd-icmp6-nd.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/src/libsystemd-network/sd-icmp6-nd.c b/src/libsystemd-network/sd-icmp6-nd.c index 8b567e3a5c..eb00b1ab32 100644 --- a/src/libsystemd-network/sd-icmp6-nd.c +++ b/src/libsystemd-network/sd-icmp6-nd.c @@ -249,6 +249,201 @@ int sd_icmp6_ra_get_mtu(sd_icmp6_nd *nd, uint32_t *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); + + icmp6_nd_notify(nd, + ICMP6_EVENT_ROUTER_ADVERTISMENT_PREFIX_EXPIRED); + 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; +} + +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; @@ -270,6 +465,7 @@ static int icmp6_ra_parse(sd_icmp6_nd *nd, struct nd_router_advert *ra, 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; @@ -289,6 +485,12 @@ static int icmp6_ra_parse(sd_icmp6_nd *nd, struct nd_router_advert *ra, 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; |