set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -g -std=c99")
add_definitions(-D_GNU_SOURCE -Wall -Werror -Wextra -pedantic)
-add_executable(odhcp6c src/odhcp6c.c src/dhcpv6.c
- src/rtnetlink.c src/script.c)
+add_executable(odhcp6c src/odhcp6c.c src/dhcpv6.c src/ra.c src/script.c)
target_link_libraries(odhcp6c resolv)
# Installation
static reply_handler dhcpv6_handle_advert;
static reply_handler dhcpv6_handle_rebind_reply;
static reply_handler dhcpv6_handle_reconfigure;
-static int dhcpv6_commit_advert(uint32_t elapsed);
+static int dhcpv6_commit_advert(void);
// Sockets
static int sock = -1;
-static int urandom_fd = -1;
static int ifindex = -1;
static time_t t1 = 0, t2 = 0, t3 = 0;
int init_dhcpv6(const char *ifname, int request_pd)
{
request_prefix = request_pd;
- urandom_fd = open("/dev/urandom", O_CLOEXEC | O_RDONLY);
- if (urandom_fd < 0)
- return -1;
sock = socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
}
-void dhcpv6_remove_addrs(void)
-{
- size_t ia_na_len;
- uint8_t *odata, *ia_na = odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
- uint16_t otype, olen;
- dhcpv6_for_each_option(ia_na, ia_na + ia_na_len, otype, olen, odata) {
- struct dhcpv6_ia_addr *addr = (void*)&odata[-4];
- set_rtnetlink_addr(ifindex, &addr->addr, 0, 0);
- }
-}
-
-
static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
{
// Build FQDN
void *srv_id = odhcp6c_get_state(STATE_SERVER_ID, &srv_id_len);
// Build IA_PDs
- size_t ia_pd_len;
- void *ia_pd = odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
+ size_t ia_pd_entry_len, ia_pd_len = 0;
+ void *ia_pd = NULL;
+ void *ia_pd_entries = odhcp6c_get_state(STATE_IA_PD, &ia_pd_entry_len);
struct dhcpv6_ia_hdr hdr_ia_pd = {
htons(DHCPV6_OPT_IA_PD),
htons(sizeof(hdr_ia_pd) - 4 + ia_pd_len),
.len = htons(25), .prefix = request_prefix
};
- if (ia_pd_len == 0 && request_prefix > 0 &&
+ if (ia_pd_entry_len > 0) {
+ struct odhcp6c_entry *e = ia_pd_entries;
+ size_t entries = ia_pd_entry_len / sizeof(*e);
+ struct dhcpv6_ia_prefix p[entries];
+ for (size_t i = 0; i < entries; ++i) {
+ p[i].type = htons(DHCPV6_OPT_IA_PREFIX);
+ p[i].len = htons(sizeof(p[i]) - 4U);
+ p[i].preferred = htonl(e[i].preferred);
+ p[i].valid = htonl(e[i].valid);
+ p[i].prefix = e[i].length;
+ p[i].addr = e[i].target;
+ }
+ ia_pd = p;
+ ia_pd_len = sizeof(p);
+ } else if (request_prefix > 0 &&
(type == DHCPV6_MSG_SOLICIT ||
type == DHCPV6_MSG_REQUEST)) {
ia_pd = &pref;
}
// Build IA_NAs
- size_t ia_na_len;
- void *ia_na = odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
+ size_t ia_na_entry_len, ia_na_len = 0;
+ void *ia_na = NULL;
+ void *ia_na_entries = odhcp6c_get_state(STATE_IA_NA, &ia_na_entry_len);
struct dhcpv6_ia_hdr hdr_ia_na = {
htons(DHCPV6_OPT_IA_NA),
htons(sizeof(hdr_ia_na) - 4 + ia_na_len),
1, 0, 0
};
+ if (ia_na_entry_len > 0) {
+ struct odhcp6c_entry *e = ia_na_entries;
+ size_t entries = ia_na_entry_len / sizeof(*e);
+ struct dhcpv6_ia_addr p[entries];
+ for (size_t i = 0; i < entries; ++i) {
+ p[i].type = htons(DHCPV6_OPT_IA_ADDR);
+ p[i].len = htons(sizeof(p[i]) - 4U);
+ p[i].addr = e[i].target;
+ p[i].preferred = htonl(e[i].preferred);
+ p[i].valid = htonl(e[i].valid);
+ }
+ ia_na = p;
+ ia_na_len = sizeof(p);
+ }
+
// Reconfigure Accept
struct {
uint16_t type;
static int64_t dhcpv6_rand_delay(int64_t time)
{
int random;
- read(urandom_fd, &random, sizeof(random));
+ odhcp6c_random(&random, sizeof(random));
return (time * (random % 1000)) / 10000;
}
// Generate transaction ID
uint8_t trid[3];
- read(urandom_fd, trid, sizeof(trid));
+ odhcp6c_random(trid, sizeof(trid));
ssize_t len = -1;
int64_t rto = 0;
for (; len < 0 && round_start < round_end;
round_start = odhcp6c_get_milli_time()) {
// Check for pending signal
- if (odhcp6c_signal_is_pending())
+ if (odhcp6c_signal_process())
return -1;
// Set timeout for receiving
"%ums", (unsigned)elapsed);
if (retx->handler_reply)
- len = retx->handler_reply(type,
- opt, opt_end, elapsed / 1000);
+ len = retx->handler_reply(
+ type, opt, opt_end);
}
}
// Allow
if (retx->handler_finish)
- len = retx->handler_finish(elapsed / 1000);
+ len = retx->handler_finish();
} while (len < 0 && elapsed / 1000 < timeout);
return len;
static int dhcpv6_handle_reconfigure(_unused enum dhcpv6_msg orig,
- const void *opt, const void *end, uint32_t elapsed)
+ const void *opt, const void *end)
{
// TODO: should verify the reconfigure message
uint16_t otype, olen;
odata[0] == DHCPV6_MSG_INFO_REQ))
msg = odata[0];
- t1 -= elapsed;
- t2 -= elapsed;
- t3 -= elapsed;
-
- if (t1 < 0)
- t1 = 0;
-
- if (t2 < 0)
- t2 = 0;
-
- if (t3 < 0)
- t3 = 0;
-
- dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, NULL, NULL, elapsed);
+ dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, NULL, NULL);
return msg;
}
// Collect all advertised servers
static int dhcpv6_handle_advert(_unused enum dhcpv6_msg orig,
- const void *opt, const void *end, _unused uint32_t elapsed)
+ const void *opt, const void *end)
{
uint16_t olen, otype;
uint8_t *odata;
}
-static int dhcpv6_commit_advert(_unused uint32_t elapsed)
+static int dhcpv6_commit_advert(void)
{
size_t cand_len;
struct dhcpv6_server_cand *c = NULL, *cand =
static int dhcpv6_handle_rebind_reply(enum dhcpv6_msg orig,
- const void *opt, const void *end, uint32_t elapsed)
+ const void *opt, const void *end)
{
- dhcpv6_handle_advert(orig, opt, end, elapsed);
- if (dhcpv6_commit_advert(elapsed) < 0)
+ dhcpv6_handle_advert(orig, opt, end);
+ if (dhcpv6_commit_advert() < 0) {
+ dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, NULL, NULL);
return -1;
+ }
- return dhcpv6_handle_reply(orig, opt, end, elapsed);
+ return dhcpv6_handle_reply(orig, opt, end);
}
-static int dhcpv6_handle_reply(_unused enum dhcpv6_msg orig,
- const void *opt, const void *end, uint32_t elapsed)
+static int dhcpv6_handle_reply(enum dhcpv6_msg orig,
+ const void *opt, const void *end)
{
- uint16_t otype, olen;
uint8_t *odata;
- bool have_update = false;
-
- t1 = t2 = t3 = 86400;
-
- size_t ia_na_len, dns_len, search_len, sntp_ip_len, sntp_dns_len;
- size_t sip_ip_len, sip_fqdn_len;
- uint8_t *ia_na = odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
- uint8_t *ia_end;
- odhcp6c_get_state(STATE_DNS, &dns_len);
- odhcp6c_get_state(STATE_SEARCH, &search_len);
- odhcp6c_get_state(STATE_SNTP_IP, &sntp_ip_len);
- odhcp6c_get_state(STATE_SNTP_FQDN, &sntp_dns_len);
- odhcp6c_get_state(STATE_SIP_IP, &sip_ip_len);
- odhcp6c_get_state(STATE_SIP_FQDN, &sip_fqdn_len);
-
- // Decrease valid and preferred lifetime of prefixes
- size_t ia_pd_len;
- uint8_t *ia_pd = odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
- dhcpv6_for_each_option(ia_pd, ia_pd + ia_pd_len, otype, olen, odata) {
- struct dhcpv6_ia_prefix *p = (void*)&odata[-4];
- uint32_t valid = ntohl(p->valid);
- if (valid != UINT32_MAX)
- p->valid = (valid < elapsed) ? 0 : htonl(valid - elapsed);
-
- uint32_t pref = ntohl(p->preferred);
- if (pref != UINT32_MAX)
- p->preferred = (pref < elapsed) ? 0 : htonl(pref - elapsed);
- }
+ uint16_t otype, olen;
- // Decrease valid and preferred lifetime of addresses
- dhcpv6_for_each_option(ia_na, ia_na + ia_na_len, otype, olen, odata) {
- struct dhcpv6_ia_addr *p = (void*)&odata[-4];
- uint32_t valid = ntohl(p->valid);
- if (valid != UINT32_MAX)
- p->valid = (valid < elapsed) ? 0 : htonl(valid - elapsed);
+ static time_t last_update = 0;
+ time_t now = odhcp6c_get_milli_time() / 1000;
+
+ uint32_t elapsed = now - last_update;
+ odhcp6c_expire();
+
+ if (orig == DHCPV6_MSG_UNKNOWN) {
+ t1 -= elapsed;
+ t2 -= elapsed;
+ t3 -= elapsed;
+
+ if (t1 < 0)
+ t1 = 0;
+
+ if (t2 < 0)
+ t2 = 0;
+
+ if (t3 < 0)
+ t3 = 0;
+ } else {
+ t1 = t2 = t3 = 86400;
+ }
- uint32_t pref = ntohl(p->preferred);
- if (pref != UINT32_MAX)
- p->preferred = (pref < elapsed) ? 0 : htonl(pref - elapsed);
+ if (opt) {
+ odhcp6c_clear_state(STATE_DNS);
+ odhcp6c_clear_state(STATE_SEARCH);
+ odhcp6c_clear_state(STATE_SNTP_IP);
+ odhcp6c_clear_state(STATE_SNTP_FQDN);
+ odhcp6c_clear_state(STATE_SIP_IP);
+ odhcp6c_clear_state(STATE_SIP_FQDN);
}
// Parse and find all matching IAs
if (l_t2 > 0 && t2 > l_t2)
t2 = l_t2;
- // Always report update in case we have IA_PDs so that
- // the state-script is called with updated times
- if (otype == DHCPV6_OPT_IA_PD && request_prefix)
- have_update = true;
-
time_t n = dhcpv6_parse_ia(&ia_hdr[1], odata + olen);
if (n < t1)
}
}
- if (opt) {
- have_update |= odhcp6c_commit_state(STATE_DNS, dns_len);
- have_update |= odhcp6c_commit_state(STATE_SEARCH, search_len);
- have_update |= odhcp6c_commit_state(STATE_SNTP_IP,
- sntp_ip_len);
- have_update |= odhcp6c_commit_state(STATE_SNTP_FQDN,
- sntp_dns_len);
- have_update |= odhcp6c_commit_state(STATE_SIP_IP, sip_ip_len);
- have_update |= odhcp6c_commit_state(STATE_SIP_FQDN, sip_fqdn_len);
- size_t new_ia_pd_len, new_ia_na_len;
- odhcp6c_get_state(STATE_IA_PD, &new_ia_pd_len);
- odhcp6c_get_state(STATE_IA_NA, &new_ia_na_len);
- have_update |= (new_ia_pd_len != ia_pd_len) ||
- (new_ia_na_len != ia_na_len);
- }
-
- // Delete prefixes with 0 valid-time
- ia_pd = odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
- ia_end = ia_pd + ia_pd_len;
- dhcpv6_for_each_option(ia_pd, ia_end, otype, olen, odata) {
- struct dhcpv6_ia_prefix *p = (void*)&odata[-4];
- while (!p->valid) {
- ia_end = ia_pd + odhcp6c_remove_state(STATE_IA_PD,
- (uint8_t*)p - ia_pd, olen + 4);
- have_update = true;
- }
- }
-
-
- // Delete addresses with 0 valid-time
- ia_na = odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
- ia_end = ia_na + ia_na_len;
- dhcpv6_for_each_option(ia_na, ia_end, otype, olen, odata) {
- struct dhcpv6_ia_addr *p = (void*)&odata[-4];
- while (!p->valid) {
- ia_end = ia_na + odhcp6c_remove_state(STATE_IA_NA,
- (uint8_t*)p - ia_na, olen + 4);
- have_update = true;
- }
- }
-
- return have_update;
+ return true;
}
static time_t dhcpv6_parse_ia(void *opt, void *end)
{
uint32_t timeout = UINT32_MAX; // Minimum timeout
- uint16_t otype, olen, stype, slen;
- uint8_t *odata, *sdata;
+ uint16_t otype, olen;
+ uint8_t *odata;
+
+ struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT,
+ 0, 0, IN6ADDR_ANY_INIT, 0, 0};
// Update address IA
dhcpv6_for_each_option(opt, end, otype, olen, odata) {
if (olen + 4U < sizeof(*prefix))
continue;
- olen = sizeof(*prefix); // Normalize length
- uint32_t valid = ntohl(prefix->valid);
- uint32_t pref = ntohl(prefix->preferred);
+ entry.valid = ntohl(prefix->valid);
+ entry.preferred = ntohl(prefix->preferred);
- if (pref > valid)
+ if (entry.preferred > entry.valid)
continue;
- // Search matching IA
- struct dhcpv6_ia_prefix *local = NULL;
- size_t pd_len;
- uint8_t *pd = odhcp6c_get_state(STATE_IA_PD, &pd_len);
- dhcpv6_for_each_option(pd, pd + pd_len,
- stype, slen, sdata)
- if (!memcmp(sdata + 8, odata + 8,
- sizeof(local->addr) + 1))
- local = (void*)&sdata[-4];
-
- if (local) { // Already know that IA
- local->preferred = prefix->preferred;
- local->valid = prefix->valid;
- } else { // New IA
- odhcp6c_add_state(STATE_IA_PD, prefix, olen);
- }
+ entry.length = prefix->prefix;
+ entry.target = prefix->addr;
- if (timeout > valid)
- timeout = valid;
+ odhcp6c_update_entry(STATE_IA_PD, &entry);
} else if (otype == DHCPV6_OPT_IA_ADDR) {
struct dhcpv6_ia_addr *addr = (void*)&odata[-4];
if (olen + 4U < sizeof(*addr))
continue;
- olen = sizeof(*addr); // Normalize length
- uint32_t pref = ntohl(addr->preferred);
- uint32_t valid = ntohl(addr->valid);
+ entry.preferred = ntohl(addr->preferred);
+ entry.valid = ntohl(addr->valid);
- if (pref > valid)
+ if (entry.preferred > entry.valid)
continue;
- // Search matching IA
- struct dhcpv6_ia_addr *local = NULL;
- size_t na_len;
- uint8_t *na = odhcp6c_get_state(STATE_IA_NA, &na_len);
- dhcpv6_for_each_option(na, na + na_len,
- stype, slen, sdata)
- if (!memcmp(sdata, odata, sizeof(local->addr)))
- local = (void*)&sdata[-4];
-
+ entry.length = 128;
+ entry.target = addr->addr;
- if (local) { // Already know that IA
- local->preferred = addr->preferred;
- local->valid = addr->valid;
- } else { // New IA
- odhcp6c_add_state(STATE_IA_NA, addr, olen);
- }
-
-
- if (timeout > valid)
- timeout = valid;
-
- if (set_rtnetlink_addr(ifindex, &addr->addr,
- pref, valid) == -EADDRNOTAVAIL) {
- dhcpv6_request(DHCPV6_MSG_DECLINE);
- raise(SIGUSR2);
- }
+ odhcp6c_update_entry(STATE_IA_NA, &entry);
}
+
+ if (entry.valid > 0 && timeout > entry.valid)
+ timeout = entry.valid;
}
return timeout;
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
+#include <stddef.h>
#include <unistd.h>
#include <syslog.h>
#include <signal.h>
#include <sys/syscall.h>
#include "odhcp6c.h"
+#include "ra.h"
static void sighandler(int signal);
static size_t state_len[_STATE_MAX] = {0};
static volatile int do_signal = 0;
+static int urandom_fd = -1;
+static bool bound = false;
int main(_unused int argc, char* const argv[])
if (help || !ifname)
return usage();
- if (init_dhcpv6(ifname, request_pd) || init_rtnetlink() ||
+ if ((urandom_fd = open("/dev/urandom", O_CLOEXEC | O_RDONLY)) < 0 ||
+ init_dhcpv6(ifname, request_pd) || ra_init(ifname) ||
script_init(script, ifname)) {
syslog(LOG_ERR, "failed to initialize: %s", strerror(errno));
return 3;
}
+ signal(SIGIO, sighandler);
signal(SIGHUP, sighandler);
signal(SIGINT, sighandler);
signal(SIGCHLD, sighandler);
odhcp6c_clear_state(STATE_SIP_IP);
odhcp6c_clear_state(STATE_SIP_FQDN);
dhcpv6_set_ia_na_mode(ia_na_mode);
+ bound = false;
do_signal = 0;
int res = dhcpv6_request(DHCPV6_MSG_SOLICIT);
else if (res > 0)
script_call("informed");
+ bound = true;
+
if (dhcpv6_poll_reconfigure() > 0)
script_call("informed");
}
continue;
script_call("bound");
+ bound = true;
while (do_signal == 0 || do_signal == SIGUSR1) {
// Renew Cycle
odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
// Add all prefixes to lost prefixes
- odhcp6c_clear_state(STATE_IA_PD);
+ bound = false;
script_call("unbound");
- // Remove assigned addresses
- if (ia_na_len > 0)
- dhcpv6_remove_addrs();
-
if (server_id_len > 0 && (ia_pd_len > 0 || ia_na_len > 0))
dhcpv6_request(DHCPV6_MSG_RELEASE);
+
+ odhcp6c_clear_state(STATE_IA_NA);
+ odhcp6c_clear_state(STATE_IA_PD);
}
script_call("stopped");
}
-bool odhcp6c_signal_is_pending(void)
+bool odhcp6c_signal_process(void)
{
+ if (do_signal == SIGIO) {
+ do_signal = 0;
+ bool updated = ra_process();
+ updated |= ra_rtnl_process();
+ if (updated && bound) {
+ odhcp6c_expire();
+ script_call("ra-updated");
+ }
+ }
+
return do_signal != 0;
}
}
-bool odhcp6c_commit_state(enum odhcp6c_state state, size_t old_len)
+void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
+{
+ *len = state_len[state];
+ return state_data[state];
+}
+
+
+struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new)
{
- size_t new_len = state_len[state] - old_len;
- uint8_t *old_data = state_data[state], *new_data = old_data + old_len;
- bool upd = new_len != old_len || memcmp(old_data, new_data, new_len);
+ size_t len, cmplen = offsetof(struct odhcp6c_entry, target) + new->length / 8;
+ struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
+ struct odhcp6c_entry *x = NULL;
- memmove(old_data, new_data, new_len);
- odhcp6c_resize_state(state, -old_len);
+ for (struct odhcp6c_entry *c = start; !x && c < &start[len/sizeof(*c)]; ++c)
+ if (!memcmp(c, new, cmplen))
+ return c;
- return upd;
+ return NULL;
}
-void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
+void odhcp6c_update_entry_safe(enum odhcp6c_state state, const struct odhcp6c_entry *new, uint32_t safe)
{
- *len = state_len[state];
- return state_data[state];
+ size_t len;
+ struct odhcp6c_entry *x = odhcp6c_find_entry(state, new);
+ struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
+
+ if (x && x->valid > new->valid && new->valid < safe)
+ return;
+
+ if (new->valid > 0) {
+ if (x)
+ *x = *new;
+ else
+ odhcp6c_add_state(state, new, sizeof(*new));
+ } else if (x) {
+ odhcp6c_remove_state(state, (x - start) * sizeof(*x), sizeof(*x));
+ }
+}
+
+
+void odhcp6c_update_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new)
+{
+ odhcp6c_update_entry_safe(state, new, 0);
+}
+
+
+static void odhcp6c_expire_list(enum odhcp6c_state state, uint32_t elapsed)
+{
+ size_t len;
+ struct odhcp6c_entry *start = odhcp6c_get_state(state, &len);
+ for (struct odhcp6c_entry *c = start; c < &start[len / sizeof(*c)]; ++c) {
+ if (c->preferred < elapsed)
+ c->preferred = 0;
+ else if (c->preferred != UINT32_MAX)
+ c->preferred -= elapsed;
+
+ if (c->valid < elapsed)
+ c->valid = 0;
+ else if (c->valid != UINT32_MAX)
+ c->valid -= elapsed;
+
+ if (!c->valid)
+ odhcp6c_remove_state(state, (c - start) * sizeof(*c), sizeof(*c));
+ }
+}
+
+
+void odhcp6c_expire(void)
+{
+ static time_t last_update = 0;
+ time_t now = odhcp6c_get_milli_time() / 1000;
+
+ uint32_t elapsed = now - last_update;
+ last_update = now;
+
+ odhcp6c_expire_list(STATE_RA_PREFIX, elapsed);
+ odhcp6c_expire_list(STATE_RA_ROUTE, elapsed);
+ odhcp6c_expire_list(STATE_IA_NA, elapsed);
+ odhcp6c_expire_list(STATE_IA_PD, elapsed);
+}
+
+
+void odhcp6c_random(void *buf, size_t len)
+{
+ read(urandom_fd, buf, len);
}
do_signal = SIGUSR1;
else if (signal == SIGUSR2)
do_signal = SIGUSR2;
+ else if (signal == SIGIO)
+ do_signal = SIGIO;
else
do_signal = SIGTERM;
}
};
typedef int(reply_handler)(enum dhcpv6_msg orig,
- const void *opt, const void *end, uint32_t elapsed);
+ const void *opt, const void *end);
// retransmission strategy
struct dhcpv6_retx {
uint16_t max_timeo;
char name[8];
reply_handler *handler_reply;
- int(*handler_finish)(uint32_t elapsed);
+ int(*handler_finish)(void);
};
STATE_SNTP_FQDN,
STATE_SIP_IP,
STATE_SIP_FQDN,
+ STATE_RA_ROUTE,
+ STATE_RA_PREFIX,
_STATE_MAX
};
};
+struct odhcp6c_entry {
+ struct in6_addr router;
+ uint16_t length;
+ int16_t priority;
+ struct in6_addr target;
+ uint32_t valid;
+ uint32_t preferred;
+};
+
+
int init_dhcpv6(const char *ifname, int request_pd);
void dhcpv6_set_ia_na_mode(enum odhcp6c_ia_mode mode);
int dhcpv6_request(enum dhcpv6_msg type);
int dhcpv6_poll_reconfigure(void);
-void dhcpv6_remove_addrs(void);
int init_rtnetlink(void);
int set_rtnetlink_addr(int ifindex, const struct in6_addr *addr,
ssize_t script_unhexlify(uint8_t *dst, size_t len, const char *src);
void script_call(const char *status);
+bool odhcp6c_signal_process(void);
+uint64_t odhcp6c_get_milli_time(void);
+void odhcp6c_random(void *buf, size_t len);
// State manipulation
-bool odhcp6c_signal_is_pending(void);
-uint64_t odhcp6c_get_milli_time(void);
void odhcp6c_clear_state(enum odhcp6c_state state);
void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len);
size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len);
-bool odhcp6c_commit_state(enum odhcp6c_state state, size_t old_len);
void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len);
+// Entry manipulation
+struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new);
+void odhcp6c_update_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new);
+void odhcp6c_update_entry_safe(enum odhcp6c_state state, const struct odhcp6c_entry *new, uint32_t safe);
+
+void odhcp6c_expire(void);
--- /dev/null
+#include <fcntl.h>
+#include <stdio.h>
+#include <signal.h>
+#include <string.h>
+#include <stddef.h>
+#include <stdbool.h>
+#include <unistd.h>
+
+#include <net/if.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/icmp6.h>
+
+#include <linux/rtnetlink.h>
+
+
+#include "odhcp6c.h"
+#include "ra.h"
+
+
+static int sock = -1, rtnl_sock = -1;
+static unsigned if_index = 0;
+static char if_name[IF_NAMESIZE] = {0};
+static volatile int rs_attempt = 1;
+static struct in6_addr lladdr = IN6ADDR_ANY_INIT;
+
+static void ra_send_rs(int signal __attribute__((unused)));
+
+int ra_init(const char *ifname)
+{
+ sock = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC, IPPROTO_ICMPV6);
+ if_index = if_nametoindex(ifname);
+ strncpy(if_name, ifname, sizeof(if_name) - 1);
+
+ // Filter ICMPv6 package types
+ struct icmp6_filter filt;
+ ICMP6_FILTER_SETBLOCKALL(&filt);
+ ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt);
+ setsockopt(sock, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, sizeof(filt));
+
+ // Bind to all-nodes
+ struct ipv6_mreq an = {ALL_IPV6_NODES, if_index};
+ setsockopt(sock, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &an, sizeof(an));
+
+ // Let the kernel compute our checksums
+ int val = 2;
+ setsockopt(sock, IPPROTO_RAW, IPV6_CHECKSUM, &val, sizeof(val));
+
+ // This is required by RFC 4861
+ val = 255;
+ setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &val, sizeof(val));
+
+ // Bind to one device
+ setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname));
+
+ // Add async-mode
+ const pid_t ourpid = getpid();
+ fcntl(sock, F_SETOWN, ourpid);
+ fcntl(sock, F_SETFL, fcntl(sock, F_GETFL) | O_ASYNC);
+
+ // Get LL-addr
+ FILE *fp = fopen("/proc/net/if_inet6", "r");
+ if (fp) {
+ char addrbuf[33], ifbuf[16];
+ while (fscanf(fp, "%32s %*x %*x %*x %*x %15s", addrbuf, ifbuf) == 2) {
+ if (!strcmp(ifbuf, if_name)) {
+ script_unhexlify((uint8_t*)&lladdr, sizeof(lladdr), addrbuf);
+ break;
+ }
+ }
+ fclose(fp);
+ }
+
+ // Open rtnetlink socket
+ rtnl_sock = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, NETLINK_ROUTE);
+ struct sockaddr_nl rtnl_kernel = { .nl_family = AF_NETLINK };
+ if (connect(rtnl_sock, (struct sockaddr*)&rtnl_kernel, sizeof(rtnl_kernel)))
+ return -1;
+ uint32_t group = RTNLGRP_IPV6_IFADDR;
+ setsockopt(rtnl_sock, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &group, sizeof(group));
+
+ // Add async-mode
+ fcntl(rtnl_sock, F_SETOWN, ourpid);
+ fcntl(rtnl_sock, F_SETFL, fcntl(rtnl_sock, F_GETFL) | O_ASYNC);
+
+ // Send RS
+ signal(SIGALRM, ra_send_rs);
+ ra_send_rs(SIGALRM);
+
+ return 0;
+}
+
+
+static void ra_send_rs(int signal __attribute__((unused)))
+{
+ const struct icmp6_hdr rs = {ND_ROUTER_SOLICIT, 0, 0, {{0}}};
+ const struct sockaddr_in6 dest = {AF_INET6, 0, 0, ALL_IPV6_ROUTERS, if_index};
+ sendto(sock, &rs, sizeof(rs), MSG_DONTWAIT, (struct sockaddr*)&dest, sizeof(dest));
+
+ if (++rs_attempt < 3)
+ alarm(4);
+}
+
+
+static int16_t pref_to_priority(uint8_t flags)
+{
+ flags = (flags >> 3) & 0x03;
+ return (flags == 0x00) ? 1024 : (flags == 0x01) ? 512 :
+ (flags == 0x11) ? 2048 : -1;
+}
+
+
+static void update_proc(const char *sect, const char *opt, uint32_t value)
+{
+ char buf[64];
+ snprintf(buf, sizeof(buf), "/proc/sys/net/ipv6/%s/%s/%s", sect, if_name, opt);
+
+ int fd = open(buf, O_WRONLY);
+ write(fd, buf, snprintf(buf, sizeof(buf), "%u", value));
+ close(fd);
+}
+
+
+static bool ra_deduplicate(const struct in6_addr *any, uint8_t length)
+{
+ struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, length, 0, *any, 0, 0};
+ struct odhcp6c_entry *x = odhcp6c_find_entry(STATE_RA_PREFIX, &entry);
+ if (x) {
+ odhcp6c_random(&x->target.s6_addr32[2], 2 * sizeof(uint32_t));
+ } else if (odhcp6c_find_entry(STATE_IA_NA, &entry)) {
+ dhcpv6_request(DHCPV6_MSG_DECLINE);
+ raise(SIGUSR2);
+ }
+
+ return !!x;
+}
+
+
+bool ra_rtnl_process(void)
+{
+ bool found = false;
+ uint8_t buf[8192];
+ while (true) {
+ ssize_t len = recv(rtnl_sock, buf, sizeof(buf), MSG_DONTWAIT);
+ if (len < 0)
+ break;
+
+ for (struct nlmsghdr *nh = (struct nlmsghdr*)buf; NLMSG_OK(nh, len);
+ nh = NLMSG_NEXT(nh, len)) {
+ struct ifaddrmsg *ifa = NLMSG_DATA(nh);
+ struct in6_addr *addr = NULL;
+ if (nh->nlmsg_type != RTM_NEWADDR || NLMSG_PAYLOAD(nh, 0) < sizeof(*ifa) ||
+ !(ifa->ifa_flags & IFA_F_DADFAILED) ||
+ ifa->ifa_index != if_index)
+ continue;
+
+ ssize_t alen = NLMSG_PAYLOAD(nh, sizeof(*ifa));
+ for (struct rtattr *rta = (struct rtattr*)&ifa[1]; RTA_OK(rta, alen);
+ rta = RTA_NEXT(rta, alen))
+ if (rta->rta_type == IFA_LOCAL && RTA_PAYLOAD(rta) >= sizeof(*addr))
+ addr = RTA_DATA(rta);
+
+ if (addr)
+ found |= ra_deduplicate(addr, ifa->ifa_prefixlen);
+ }
+ }
+ return found;
+}
+
+
+bool ra_process(void)
+{
+ bool found = false;
+ uint8_t buf[1500];
+ struct nd_router_advert *adv = (struct nd_router_advert*)buf;
+ struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, 0, 0, IN6ADDR_ANY_INIT, 0, 0};
+ const struct in6_addr any = IN6ADDR_ANY_INIT;
+ odhcp6c_expire();
+
+ while (true) {
+ struct sockaddr_in6 from;
+ socklen_t from_len = sizeof(from);
+ ssize_t len = recvfrom(sock, buf, sizeof(buf), MSG_DONTWAIT, &from, &from_len);
+ if (len < 0)
+ break;
+ else if (len < (ssize_t)sizeof(*adv))
+ continue;
+
+ // Stop sending solicits
+ if (rs_attempt > 0) {
+ alarm(0);
+ rs_attempt = 0;
+ }
+
+ found = true;
+
+ // Parse default route
+ entry.router = from.sin6_addr;
+ entry.priority = pref_to_priority(adv->nd_ra_flags_reserved);
+ if (entry.priority < 0)
+ entry.priority = pref_to_priority(0);
+ entry.valid = ntohs(adv->nd_ra_router_lifetime);
+ entry.preferred = entry.valid;
+ odhcp6c_update_entry(STATE_RA_ROUTE, &entry);
+
+ // Parse ND parameters
+ if (adv->nd_ra_reachable)
+ update_proc("neigh", "base_reachable_time_ms", ntohl(adv->nd_ra_reachable));
+
+ if (adv->nd_ra_retransmit)
+ update_proc("neigh", "retrans_time_ms", ntohl(adv->nd_ra_retransmit));
+
+ // Evaluate options
+ struct icmpv6_opt *opt;
+ icmpv6_for_each_option(opt, &adv[1], &buf[len]) {
+ if (opt->type == ND_OPT_MTU) {
+ update_proc("conf", "mtu", ntohl(*((uint32_t*)&opt->data[2])));
+ } else if (opt->type == ND_OPT_ROUTE_INFORMATION && opt->len <= 3) {
+ entry.router = from.sin6_addr;
+ entry.target = any;
+ entry.priority = pref_to_priority(opt->data[1]);
+ entry.length = opt->data[0];
+ entry.valid = ntohl(*((uint32_t*)&opt->data[2]));
+ memcpy(&entry.target, &opt->data[6], (opt->len - 1) * 8);
+
+ if (entry.length > 128 || IN6_IS_ADDR_LINKLOCAL(&entry.target)
+ || IN6_IS_ADDR_LOOPBACK(&entry.target)
+ || IN6_IS_ADDR_MULTICAST(&entry.target))
+ continue;
+
+ if (entry.priority > 0)
+ odhcp6c_update_entry(STATE_RA_ROUTE, &entry);
+ } else if (opt->type == ND_OPT_PREFIX_INFORMATION && opt->len == 4) {
+ struct nd_opt_prefix_info *pinfo = (struct nd_opt_prefix_info*)opt;
+ entry.router = any;
+ entry.target = pinfo->nd_opt_pi_prefix;
+ entry.priority = 0;
+ entry.length = pinfo->nd_opt_pi_prefix_len;
+ entry.valid = ntohl(pinfo->nd_opt_pi_valid_time);
+ entry.preferred = ntohl(pinfo->nd_opt_pi_preferred_time);
+
+ if (entry.length > 128 || IN6_IS_ADDR_LINKLOCAL(&entry.target)
+ || IN6_IS_ADDR_LOOPBACK(&entry.target)
+ || IN6_IS_ADDR_MULTICAST(&entry.target)
+ || entry.valid < entry.preferred)
+ continue;
+
+ if (pinfo->nd_opt_pi_flags_reserved & ND_OPT_PI_FLAG_ONLINK)
+ odhcp6c_update_entry_safe(STATE_RA_ROUTE, &entry, 7201);
+
+ if (!(pinfo->nd_opt_pi_flags_reserved & ND_OPT_PI_FLAG_AUTO) ||
+ pinfo->nd_opt_pi_prefix_len != 64)
+ continue;
+
+ entry.target.s6_addr32[2] = lladdr.s6_addr32[2];
+ entry.target.s6_addr32[3] = lladdr.s6_addr32[3];
+
+ odhcp6c_update_entry_safe(STATE_RA_PREFIX, &entry, 7201);
+ }
+
+ }
+ }
+ return found;
+}
--- /dev/null
+#pragma once
+
+#define ALL_IPV6_NODES {{{0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}}}
+
+#define ALL_IPV6_ROUTERS {{{0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02}}}
+
+struct icmpv6_opt {
+ uint8_t type;
+ uint8_t len;
+ uint8_t data[6];
+};
+
+#define ND_OPT_ROUTE_INFORMATION 24
+
+
+#define icmpv6_for_each_option(opt, start, end)\
+ for (opt = (struct icmpv6_opt*)(start);\
+ (void*)(opt + 1) <= (void*)(end) && opt->len > 0 &&\
+ (void*)(opt + opt->len) <= (void*)(end); opt += opt->len)
+
+
+int ra_init(const char *ifname);
+bool ra_process(void);
+bool ra_rtnl_process(void);
+++ /dev/null
-/**
- * Copyright (C) 2012 Steven Barth <steven@midlink.org>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License v2 as published by
- * the Free Software Foundation.
- *
- * This program 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 General Public License for more details.
- *
- */
-
-#include <time.h>
-#include <errno.h>
-#include <stdlib.h>
-#include <string.h>
-#include <syslog.h>
-#include <stdbool.h>
-#include <arpa/inet.h>
-#include <sys/socket.h>
-#include <linux/rtnetlink.h>
-
-#include "odhcp6c.h"
-
-
-static int sock = -1;
-static unsigned seq = 0;
-
-
-// Init rtnetlink socket
-int init_rtnetlink(void)
-{
- sock = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, NETLINK_ROUTE);
- struct sockaddr_nl rtnl_kernel = { .nl_family = AF_NETLINK };
- if (connect(sock, (struct sockaddr*)&rtnl_kernel, sizeof(rtnl_kernel)))
- return -1;
-
- return 0;
-}
-
-
-// CRUD addresses to interface
-int set_rtnetlink_addr(int ifindex, const struct in6_addr *addr,
- uint32_t pref, uint32_t valid)
-{
- int flags = NLM_F_REQUEST | NLM_F_ACK;
- int cmd = RTM_DELADDR;
-
- if (valid) {
- flags |= NLM_F_CREATE | NLM_F_REPLACE;
- cmd = RTM_NEWADDR;
- }
-
- struct {
- struct nlmsghdr nhm;
- struct ifaddrmsg ifa;
- struct rtattr rta_addr;
- struct in6_addr addr;
- struct rtattr rta_local;
- struct in6_addr local;
- struct rtattr rta_info;
- struct ifa_cacheinfo info;
- } req = {
- {sizeof(req), cmd, flags, ++seq, 0},
- {AF_INET6, 128, 0, RT_SCOPE_UNIVERSE, ifindex},
- {sizeof(req.rta_addr) + sizeof(req.addr), IFA_ADDRESS},
- *addr,
- {sizeof(req.rta_local) + sizeof(req.local), IFA_LOCAL},
- *addr,
- {sizeof(req.rta_info) + sizeof(req.info), IFA_CACHEINFO},
- {pref, valid, 0, 0}
- };
- send(sock, &req, sizeof(req), 0);
-
- struct {
- struct nlmsghdr nhm;
- struct nlmsgerr err;
- } reply;
- recv(sock, &reply, sizeof(reply), 0);
-
- char buf[INET6_ADDRSTRLEN];
- inet_ntop(AF_INET6, addr, buf, sizeof(buf));
- syslog(LOG_WARNING, "%s address %s/128 for iface %i: %s",
- (valid) ? "assigning" : "removing", buf,
- ifindex, strerror(-reply.err.error));
-
- if (reply.err.error < 0 || valid == 0)
- return reply.err.error;
-
- // Check for duplicate addresses
- struct timespec ts = {1, 0};
- nanosleep(&ts, NULL);
-
- req.nhm.nlmsg_type = RTM_GETADDR;
- req.nhm.nlmsg_seq = ++seq;
- req.nhm.nlmsg_flags = NLM_F_REQUEST;
- send(sock, &req, sizeof(req), 0);
-
- struct {
- struct nlmsghdr nhm;
- struct ifaddrmsg ifa;
- uint8_t buf[1024];
- } dad_reply;
- recv(sock, &dad_reply, sizeof(dad_reply), 0);
-
- if (dad_reply.nhm.nlmsg_type != RTM_NEWADDR ||
- (dad_reply.ifa.ifa_flags & IFA_F_DADFAILED)) {
- syslog(LOG_WARNING, "Removing duplicate address %s", buf);
- set_rtnetlink_addr(ifindex, addr, 0, 0);
- return -EADDRNOTAVAIL;
- }
- return 0;
-}
}
-void script_hexlify(char *dst, const uint8_t *src, size_t len) {
+static void script_hexlify(char *dst, const uint8_t *src, size_t len) {
for (size_t i = 0; i < len; ++i) {
*dst++ = hexdigits[src[i] >> 4];
*dst++ = hexdigits[src[i] & 0x0f];
}
-static void prefix_to_env(const char *name, const uint8_t *fqdn, size_t len)
+static void entry_to_env(const char *name, const void *data, size_t len)
{
size_t buf_len = strlen(name);
- struct dhcpv6_ia_prefix *p = NULL;
- char *buf = realloc(NULL, buf_len + 2 +
- (len / sizeof(*p)) * (INET6_ADDRSTRLEN + 32));
+ const struct odhcp6c_entry *e = data;
+ const struct in6_addr any = IN6ADDR_ANY_INIT;
+ char *buf = realloc(NULL, buf_len + 2 + (len / sizeof(*e)) * 144);
memcpy(buf, name, buf_len);
buf[buf_len++] = '=';
- uint16_t otype, olen;
- uint8_t *odata;
- dhcpv6_for_each_option(fqdn, &fqdn[len], otype, olen, odata) {
- if (otype != DHCPV6_OPT_IA_PREFIX || olen + 4U < sizeof(*p))
- continue;
-
- p = (struct dhcpv6_ia_prefix*)&odata[-4];
- inet_ntop(AF_INET6, &p->addr, &buf[buf_len], INET6_ADDRSTRLEN);
+ for (size_t i = 0; i < len / sizeof(*e); ++i) {
+ inet_ntop(AF_INET6, &e[i].target, &buf[buf_len], INET6_ADDRSTRLEN);
buf_len += strlen(&buf[buf_len]);
- buf_len += snprintf(&buf[buf_len], 32, "/%hhu,%u,%u ",
- p->prefix, ntohl(p->preferred),
- ntohl(p->valid));
+ buf_len += snprintf(&buf[buf_len], 6, "/%hhu", e[i].length);
+ if (!IN6_ARE_ADDR_EQUAL(&any, &e[i].router)) {
+ buf[buf_len++] = '@';
+ inet_ntop(AF_INET6, &e[i].router, &buf[buf_len], INET6_ADDRSTRLEN);
+ buf_len += strlen(&buf[buf_len]);
+ }
+ buf_len += snprintf(&buf[buf_len], 24, ",%u,%u", e[i].preferred, e[i].valid);
+ if (e[i].priority)
+ buf_len += snprintf(&buf[buf_len], 12, ",%u", e[i].priority);
+ buf[buf_len++] = ' ';
}
+
buf[buf_len - 1] = '\0';
putenv(buf);
}
struct in6_addr *sip = odhcp6c_get_state(STATE_SIP_IP, &sip_ip_len);
uint8_t *sip_fqdn = odhcp6c_get_state(STATE_SIP_FQDN, &sip_fqdn_len);
- size_t prefix_len;
+ size_t prefix_len, address_len, ra_pref_len, ra_route_len;
uint8_t *prefix = odhcp6c_get_state(STATE_IA_PD, &prefix_len);
+ uint8_t *address = odhcp6c_get_state(STATE_IA_NA, &address_len);
+ uint8_t *ra_pref = odhcp6c_get_state(STATE_RA_PREFIX, &ra_pref_len);
+ uint8_t *ra_route = odhcp6c_get_state(STATE_RA_ROUTE, &ra_route_len);
// Don't set environment before forking, because env is leaky.
if (fork() == 0) {
fqdn_to_env("SNTP_FQDN", sntp_dns, sntp_dns_len);
fqdn_to_env("SIP_DOMAIN", sip_fqdn, sip_fqdn_len);
bin_to_env(custom, custom_len);
- prefix_to_env("PREFIXES", prefix, prefix_len);
+ entry_to_env("PREFIXES", prefix, prefix_len);
+ entry_to_env("ADDRESSES", address, address_len);
+ entry_to_env("RA_ADDRESSES", ra_pref, ra_pref_len);
+ entry_to_env("RA_ROUTES", ra_route, ra_route_len);
argv[2] = (char*)status;
execv(argv[0], argv);
projects / oweals / odhcp6c.git / commitdiff