add option to specify minimum interval for accepting RA or DHCP updates.

This was fixed to 60s. Add '-m <seconds>' option to change default time.

1 files changed, 10 insertions, 3 deletions

diff --git a/src/odhcp6c.c b/src/odhcp6c.c
index dfd9925..798598f 100644
--- a/src/odhcp6c.c
+++ b/src/odhcp6c.c
@@ -52,6 +52,8 @@ static int urandom_fd = -1, allow_slaac_only = 0;
 static bool bound = false, release = true;
 static time_t last_update = 0;
 
+static unsigned int min_update_interval = DEFAULT_MIN_UPDATE_INTERVAL;
+
 int main(_unused int argc, char* const argv[])
 {
 	// Allocate ressources
@@ -77,7 +79,7 @@ int main(_unused int argc, char* const argv[])
 	int c;
 	unsigned int client_options = DHCPV6_CLIENT_FQDN | DHCPV6_ACCEPT_RECONFIGURE;
 
-	while ((c = getopt(argc, argv, "S::N:V:P:FB:c:i:r:Ru:s:kt:hedp:fa")) != -1) {
+	while ((c = getopt(argc, argv, "S::N:V:P:FB:c:i:r:Ru:s:kt:m:hedp:fa")) != -1) {
 		switch (c) {
 		case 'S':
 			allow_slaac_only = (optarg) ? atoi(optarg) : -1;
@@ -197,6 +199,10 @@ int main(_unused int argc, char* const argv[])
 			sol_timeout = atoi(optarg);
 			break;
 
+		case 'm':
+			min_update_interval = atoi(optarg);
+			break;
+
 		case 'e':
 			logopt |= LOG_PERROR;
 			break;
@@ -447,6 +453,7 @@ static int usage(void)
 	"	-f		Don't send Client FQDN option\n"
 	"	-k		Don't send a RELEASE when stopping\n"
 	"	-t <seconds>	Maximum timeout for DHCPv6-SOLICIT (3600)\n"
+	"	-m <seconds>	Minimum time between accepting updates (60)\n"
 	"\nInvocation options:\n"
 	"	-p <pidfile>	Set pidfile (/var/run/odhcp6c.pid)\n"
 	"	-d		Daemonize\n"
@@ -593,10 +600,10 @@ bool odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *n
 	if (new->valid > 0) {
 		if (x) {
 			if (new->valid >= x->valid && new->valid != UINT32_MAX &&
-					new->valid - x->valid < 60 &&
+					new->valid - x->valid < min_update_interval &&
 					new->preferred >= x->preferred &&
 					new->preferred != UINT32_MAX &&
-					new->preferred - x->preferred < 60 &&
+					new->preferred - x->preferred < min_update_interval &&
 					x->class == new->class)
 				return false;
 			x->valid = new->valid;