X-Git-Url: https://git.decadent.org.uk/gitweb/?p=odhcp6c.git;a=blobdiff_plain;f=src%2Fodhcp6c.c;h=f7ae2fb917e73b8d3be1d3dd6d810386dd3440d3;hp=b517204829d20fc5e02f17f07e41dcb2457d95b1;hb=6016539b9b73f3dc45b3df92554fca1b5d6431b7;hpb=5dd38d3de6bd3e249956b9bbbb0eebf998f4df2b

diff --git a/src/odhcp6c.c b/src/odhcp6c.c
index b517204..f7ae2fb 100644
--- a/src/odhcp6c.c
+++ b/src/odhcp6c.c
@@ -17,6 +17,7 @@
 #include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <stddef.h>
 #include <unistd.h>
 #include <syslog.h>
 #include <signal.h>
@@ -28,11 +29,10 @@
 #include <sys/syscall.h>
 
 #include "odhcp6c.h"
+#include "ra.h"
 
 
 static void sighandler(int signal);
-static int sysctl_interface(const char *ifname, const char *option,
-		const char *data);
 static int usage(void);
 
 
@@ -40,6 +40,8 @@ static uint8_t *state_data[_STATE_MAX] = {NULL};
 static size_t state_len[_STATE_MAX] = {0};
 
 static volatile int do_signal = 0;
+static int urandom_fd = -1;
+static bool bound = false, allow_slaac_only = true;
 
 
 int main(_unused int argc, char* const argv[])
@@ -55,12 +57,12 @@ int main(_unused int argc, char* const argv[])
 	uint16_t opttype;
 	enum odhcp6c_ia_mode ia_na_mode = IA_MODE_TRY;
 
-	bool help = false, daemonize = false, reset = false;
-	int c, request_pd = 0, timeout = 0;
-	while ((c = getopt(argc, argv, "RN:P:c:r:s:t:hdp:")) != -1) {
+	bool help = false, daemonize = false;
+	int c, request_pd = 0;
+	while ((c = getopt(argc, argv, "SN:P:c:r:s:hdp:")) != -1) {
 		switch (c) {
-		case 'R':
-			reset = true;
+		case 'S':
+			allow_slaac_only = false;
 			break;
 
 		case 'N':
@@ -75,6 +77,7 @@ int main(_unused int argc, char* const argv[])
 			break;
 
 		case 'P':
+			allow_slaac_only = false;
 			request_pd = strtoul(optarg, NULL, 10);
 			if (request_pd == 0)
 				request_pd = -1;
@@ -109,10 +112,6 @@ int main(_unused int argc, char* const argv[])
 			script = optarg;
 			break;
 
-		case 't':
-			timeout = strtoul(optarg, NULL, 10);
-			break;
-
 		case 'd':
 			daemonize = true;
 			break;
@@ -132,27 +131,21 @@ 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(SIGALRM, sighandler);
 	signal(SIGCHLD, sighandler);
 	signal(SIGTERM, sighandler);
 	signal(SIGUSR1, sighandler);
 	signal(SIGUSR2, sighandler);
 
-	// Configure interface to accept RA
-	if (reset) {
-		sysctl_interface(ifname, "accept_ra", "2");
-		sysctl_interface(ifname, "disable_ipv6", "1");
-		sysctl_interface(ifname, "disable_ipv6", "0");
-	}
-
 	if (daemonize) {
 		openlog("odhcp6c", LOG_PID, LOG_DAEMON); // Disable LOG_PERROR
 		if (daemon(0, 0)) {
@@ -177,16 +170,22 @@ int main(_unused int argc, char* const argv[])
 		}
 	}
 
+	script_call("started");
+
 	while (do_signal != SIGTERM) { // Main logic
 		odhcp6c_clear_state(STATE_SERVER_ID);
 		odhcp6c_clear_state(STATE_SERVER_CAND);
 		odhcp6c_clear_state(STATE_IA_PD);
-		odhcp6c_clear_state(STATE_IA_PD_LOST);
+		odhcp6c_clear_state(STATE_SNTP_IP);
+		odhcp6c_clear_state(STATE_SNTP_FQDN);
+		odhcp6c_clear_state(STATE_SIP_IP);
+		odhcp6c_clear_state(STATE_SIP_FQDN);
 		dhcpv6_set_ia_na_mode(ia_na_mode);
+		bound = false;
 
-		alarm(timeout);
 		do_signal = 0;
 		int res = dhcpv6_request(DHCPV6_MSG_SOLICIT);
+		odhcp6c_signal_process();
 
 		if (res < 0) {
 			continue; // Might happen if we got a signal
@@ -195,6 +194,7 @@ int main(_unused int argc, char* const argv[])
 				do_signal = 0;
 
 				res = dhcpv6_request(DHCPV6_MSG_INFO_REQ);
+				odhcp6c_signal_process();
 				if (do_signal == SIGUSR1)
 					continue;
 				else if (res < 0)
@@ -202,14 +202,12 @@ int main(_unused int argc, char* const argv[])
 				else if (res > 0)
 					script_call("informed");
 
-				alarm(0);
+				bound = true;
+
 				if (dhcpv6_poll_reconfigure() > 0)
 					script_call("informed");
 			}
 
-			if (do_signal == SIGALRM)
-				script_call("timeout");
-
 			continue;
 		}
 
@@ -217,13 +215,15 @@ int main(_unused int argc, char* const argv[])
 		if (dhcpv6_request(DHCPV6_MSG_REQUEST) < 0)
 			continue;
 
+		odhcp6c_signal_process();
 		script_call("bound");
-		alarm(0);
+		bound = true;
 
 		while (do_signal == 0 || do_signal == SIGUSR1) {
 			// Renew Cycle
 			// Wait for T1 to expire or until we get a reconfigure
 			int res = dhcpv6_poll_reconfigure();
+			odhcp6c_signal_process();
 			if (res >= 0) {
 				if (res > 0)
 					script_call("updated");
@@ -247,6 +247,7 @@ int main(_unused int argc, char* const argv[])
 				r = dhcpv6_request(DHCPV6_MSG_REQUEST);
 			else
 				r = dhcpv6_request(DHCPV6_MSG_RENEW);
+			odhcp6c_signal_process();
 			if (r > 0) // Publish updates
 				script_call("updated");
 			if (r >= 0)
@@ -256,6 +257,7 @@ int main(_unused int argc, char* const argv[])
 
 			// If we have IAs, try rebind otherwise restart
 			res = dhcpv6_request(DHCPV6_MSG_REBIND);
+			odhcp6c_signal_process();
 
 			odhcp6c_get_state(STATE_IA_PD, &ia_pd_new);
 			odhcp6c_get_state(STATE_IA_NA, &ia_na_new);
@@ -268,27 +270,22 @@ int main(_unused int argc, char* const argv[])
 
 
 		size_t ia_pd_len, ia_na_len, server_id_len;
-		uint8_t *ia_pd = odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
+		odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
 		odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
 		odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
 
 		// Add all prefixes to lost prefixes
-		odhcp6c_add_state(STATE_IA_PD_LOST, ia_pd, ia_pd_len);
-		odhcp6c_clear_state(STATE_IA_PD);
-
-		if (do_signal == SIGALRM)
-			script_call("timeout");
-		else
-			script_call("unbound");
-
-		// Remove assigned addresses
-		if (ia_na_len > 0)
-			dhcpv6_remove_addrs();
+		bound = false;
+		script_call("unbound");
 
 		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");
 	return 0;
 }
 
@@ -298,12 +295,12 @@ static int usage(void)
 	const char buf[] =
 	"Usage: odhcp6c [options] <interface>\n"
 	"\nFeature options:\n"
+	"	-S		Don't allow SLAAC-only (implied by -P)\n"
 	"	-N <mode>	Mode for requesting addresses [try|force|none]\n"
 	"	-P <length>	Request IPv6-Prefix (0 = auto)\n"
 	"	-c <clientid>	Override client-ID (base-16 encoded)\n"
 	"	-r <options>	Options to be requested (comma-separated)\n"
 	"	-s <script>	Status update script (/usr/sbin/odhcp6c-update)\n"
-	"	-t <timeout>	Request timeout after which the script is called\n"
 	"\nInvocation options:\n"
 	"	-p <pidfile>	Set pidfile (/var/run/6relayd.pid)\n"
 	"	-d		Daemonize\n"
@@ -315,7 +312,7 @@ static int usage(void)
 
 
 // Don't want to pull-in librt and libpthread just for a monotonic clock...
-uint64_t adhc6c_get_milli_time(void)
+uint64_t odhcp6c_get_milli_time(void)
 {
 	struct timespec t = {0, 0};
 	syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &t);
@@ -327,6 +324,8 @@ static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
 {
 	if (len == 0)
 		return state_data[state] + state_len[state];
+	else if (state_len[state] + len > 1024)
+		return NULL;
 
 	uint8_t *n = realloc(state_data[state], state_len[state] + len);
 	if (n || state_len[state] + len == 0) {
@@ -338,8 +337,18 @@ static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
 }
 
 
-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 || allow_slaac_only)) {
+			odhcp6c_expire();
+			script_call("ra-updated");
+		}
+	}
+
 	return do_signal != 0;
 }
 
@@ -370,38 +379,95 @@ 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)
 {
-	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);
+	*len = state_len[state];
+	return state_data[state];
+}
 
-	memmove(old_data, new_data, new_len);
-	odhcp6c_resize_state(state, -old_len);
 
-	return upd;
+struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new)
+{
+	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;
+
+	for (struct odhcp6c_entry *c = start; !x && c < &start[len/sizeof(*c)]; ++c)
+		if (!memcmp(c, new, cmplen))
+			return c;
+
+	return NULL;
 }
 
 
-void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
+void odhcp6c_update_entry_safe(enum odhcp6c_state state, 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)
+		new->valid = safe;
+
+	if (new->valid > 0) {
+		if (x) {
+			x->valid = new->valid;
+			x->preferred = new->preferred;
+		} 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, 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));
+	}
 }
 
 
-static int sysctl_interface(const char *ifname, const char *option,
-		const char *data)
+void odhcp6c_expire(void)
 {
-	char pathbuf[64];
-	const char *sysctl_pattern = "/proc/sys/net/ipv6/conf/%s/%s";
-	snprintf(pathbuf, sizeof(pathbuf), sysctl_pattern, ifname, option);
+	static time_t last_update = 0;
+	time_t now = odhcp6c_get_milli_time() / 1000;
+
+	uint32_t elapsed = now - last_update;
+	last_update = now;
 
-	int fd = open(pathbuf, O_WRONLY);
-	int written = write(fd, data, strlen(data));
-	close(fd);
+	odhcp6c_expire_list(STATE_RA_PREFIX, elapsed);
+	odhcp6c_expire_list(STATE_RA_ROUTE, elapsed);
+	odhcp6c_expire_list(STATE_RA_DNS, elapsed);
+	odhcp6c_expire_list(STATE_IA_NA, elapsed);
+	odhcp6c_expire_list(STATE_IA_PD, elapsed);
+}
 
-	return (written > 0) ? 0 : -1;
+
+void odhcp6c_random(void *buf, size_t len)
+{
+	read(urandom_fd, buf, len);
 }
 
 
@@ -413,8 +479,8 @@ static void sighandler(int signal)
 		do_signal = SIGUSR1;
 	else if (signal == SIGUSR2)
 		do_signal = SIGUSR2;
-	else if (signal == SIGALRM)
-		do_signal = SIGALRM;
+	else if (signal == SIGIO)
+		do_signal = SIGIO;
 	else
 		do_signal = SIGTERM;
 }