? dhcpleased.conf
Index: dhcpleased.conf.5
===================================================================
RCS file: /cvs/src/sbin/dhcpleased/dhcpleased.conf.5,v
retrieving revision 1.13
diff -u -p -r1.13 dhcpleased.conf.5
--- dhcpleased.conf.5	25 Nov 2023 12:00:39 -0000	1.13
+++ dhcpleased.conf.5	29 Jan 2024 08:43:02 -0000
@@ -112,6 +112,10 @@ The default is to send a DHCP host name 
 Send the DHCP vendor class identifier option with a value of
 .Ar vendor-class-id .
 The default is to not send a vendor class identifier.
+.It Ic lease time Ar lease-time-interval
+Send the specified
+.Ar lease-time-interval .
+The default is to not send a lease time interval.
 .El
 .Sh FILES
 .Bl -tag -width /etc/dhcpleased.conf -compact
Index: dhcpleased.h
===================================================================
RCS file: /cvs/src/sbin/dhcpleased/dhcpleased.h,v
retrieving revision 1.16
diff -u -p -r1.16 dhcpleased.h
--- dhcpleased.h	26 Jan 2024 21:14:08 -0000	1.16
+++ dhcpleased.h	29 Jan 2024 08:43:02 -0000
@@ -260,6 +260,7 @@ struct iface_conf {
 	struct in_addr			 ignore_servers[MAX_SERVERS];
 	int				 ignore_servers_len;
 	int				 prefer_ipv6;
+	uint32_t			 lease_time;
 };
 
 struct dhcpleased_conf {
Index: frontend.c
===================================================================
RCS file: /cvs/src/sbin/dhcpleased/frontend.c,v
retrieving revision 1.33
diff -u -p -r1.33 frontend.c
--- frontend.c	26 Jan 2024 21:14:08 -0000	1.33
+++ frontend.c	29 Jan 2024 08:43:02 -0000
@@ -1036,6 +1036,19 @@ build_packet(uint8_t message_type, char 
 		    sizeof(dhcp_server_identifier));
 		p += sizeof(dhcp_server_identifier);
 	}
+
+#ifndef SMALL
+	if (iface_conf != NULL && iface_conf->lease_time != 0) {
+		uint8_t dhcp_address_time[] = { DHO_DHCP_LEASE_TIME, 4,
+		    0, 0, 0, 0};
+		uint32_t lease_time = htonl(iface_conf->lease_time);
+
+		memcpy(dhcp_address_time + 2,
+		    &lease_time, sizeof(lease_time));
+		memcpy(p, dhcp_address_time, sizeof(dhcp_address_time));
+		p += sizeof(dhcp_address_time);
+	}
+#endif /* SMALL */
 
 	*p = DHO_END;
 	p += 1;
Index: parse.y
===================================================================
RCS file: /cvs/src/sbin/dhcpleased/parse.y,v
retrieving revision 1.8
diff -u -p -r1.8 parse.y
--- parse.y	25 Nov 2023 12:00:39 -0000	1.8
+++ parse.y	29 Jan 2024 08:43:02 -0000
@@ -109,11 +109,13 @@ typedef struct {
 %}
 
 %token	DHCP_IFACE ERROR SEND VENDOR CLASS ID CLIENT IGNORE DNS ROUTES HOST NAME
-%token	NO PREFER IPV6
+%token	NO PREFER IPV6 LEASE TIME
+%token	SECOND MINUTE HOUR DAY WEEK
 
 %token	<v.string>	STRING
 %token	<v.number>	NUMBER
 %type	<v.string>	string
+%type	<v.number>	interval interval_unit
 
 %%
 
@@ -327,6 +329,31 @@ ifaceoptsl	: SEND VENDOR CLASS ID STRING
 		| PREFER IPV6 {
 			iface_conf->prefer_ipv6 = 1;
 		}
+		| LEASE TIME interval {
+			if ($3 < 5) {
+				yyerror("least time is too low");
+				YYERROR;
+			}
+			if ($3 > (3600 * 24 * 7)) {
+				yyerror("least time is too high");
+				YYERROR;
+			}
+
+			iface_conf->lease_time = $3;
+		}
+		;
+
+interval	: NUMBER interval_unit {
+			$$ = $1 * $2;
+		}
+		;
+
+interval_unit	: /* nothing */	{ $$ = 1; }
+		| SECOND	{ $$ = 1; }
+		| MINUTE	{ $$ = 60; }
+		| HOUR		{ $$ = 60 * 60; }
+		| DAY		{ $$ = 60 * 60 * 24; }
+		| WEEK		{ $$ = 60 * 60 * 24 * 7; }
 		;
 %%
 
@@ -364,18 +391,30 @@ lookup(char *s)
 	static const struct keywords keywords[] = {
 		{"class",		CLASS},
 		{"client",		CLIENT},
+		{"day",			DAY},
+		{"days",		DAY},
 		{"dns",			DNS},
 		{"host",		HOST},
+		{"hour",		HOUR},
+		{"hours",		HOUR},
 		{"id",			ID},
 		{"ignore",		IGNORE},
 		{"interface",		DHCP_IFACE},
 		{"ipv6",		IPV6},
+		{"lease",		LEASE},
+		{"minute",		MINUTE},
+		{"minutes",		MINUTE},
 		{"name",		NAME},
 		{"no",			NO},
 		{"prefer",		PREFER},
 		{"routes",		ROUTES},
+		{"second",		SECOND},
+		{"seconds",		SECOND},
 		{"send",		SEND},
+		{"time",		TIME},
 		{"vendor",		VENDOR},
+		{"week",		WEEK},
+		{"weeks",		WEEK},
 	};
 	const struct keywords	*p;