Add per-host leasetime support

Patch by Daniel Dickinson

Signed-off-by: Steven Barth <steven@midlink.org>

6 files changed, 75 insertions, 21 deletions

diff --git a/src/config.c b/src/config.c
index 8f2c6bf..ef51112 100644
--- a/src/config.c
+++ b/src/config.c
@@ -98,6 +98,7 @@ enum {
 	LEASE_ATTR_MAC,
 	LEASE_ATTR_DUID,
 	LEASE_ATTR_HOSTID,
+	LEASE_ATTR_LEASETIME,
 	LEASE_ATTR_NAME,
 	LEASE_ATTR_MAX
 };
@@ -108,6 +109,7 @@ static const struct blobmsg_policy lease_attrs[LEASE_ATTR_MAX] = {
 	[LEASE_ATTR_MAC] = { .name = "mac", .type = BLOBMSG_TYPE_STRING },
 	[LEASE_ATTR_DUID] = { .name = "duid", .type = BLOBMSG_TYPE_STRING },
 	[LEASE_ATTR_HOSTID] = { .name = "hostid", .type = BLOBMSG_TYPE_STRING },
+	[LEASE_ATTR_LEASETIME] = { .name = "leasetime", .type = BLOBMSG_TYPE_STRING },
 	[LEASE_ATTR_NAME] = { .name = "name", .type = BLOBMSG_TYPE_STRING },
 };
 
@@ -215,6 +217,32 @@ static void set_config(struct uci_section *s)
 	}
 }
 
+static double parse_leasetime(struct blob_attr *c) {
+	char *val = blobmsg_get_string(c), *endptr;
+	double time = strtod(val, &endptr);
+	if (time && endptr[0]) {
+		if (endptr[0] == 's')
+			time *= 1;
+		else if (endptr[0] == 'm')
+			time *= 60;
+		else if (endptr[0] == 'h')
+			time *= 3600;
+		else if (endptr[0] == 'd')
+			time *= 24 * 3600;
+		else if (endptr[0] == 'w')
+			time *= 7 * 24 * 3600;
+		else
+			goto err;
+	}
+
+	if (time >= 60)
+		return time;
+
+	return 0;
+
+err:
+	return -1;
+}
 
 static int set_lease(struct uci_section *s)
 {
@@ -265,6 +293,15 @@ static int set_lease(struct uci_section *s)
 			goto err;
 	}
 
+	if ((c = tb[LEASE_ATTR_LEASETIME])) {
+		double time = parse_leasetime(c);
+		if (time < 0)
+			goto err;
+
+		if (time >= 60)
+			lease->dhcpv4_leasetime = time;
+	}
+
 	list_add(&lease->head, &leases);
 	return 0;
 
@@ -330,22 +367,9 @@ int config_parse_interface(void *data, size_t len, const char *name, bool overwr
 		iface->ignore = blobmsg_get_bool(c);
 
 	if ((c = tb[IFACE_ATTR_LEASETIME])) {
-		char *val = blobmsg_get_string(c), *endptr;
-		double time = strtod(val, &endptr);
-		if (time && endptr[0]) {
-			if (endptr[0] == 's')
-				time *= 1;
-			else if (endptr[0] == 'm')
-				time *= 60;
-			else if (endptr[0] == 'h')
-				time *= 3600;
-			else if (endptr[0] == 'd')
-				time *= 24 * 3600;
-			else if (endptr[0] == 'w')
-				time *= 7 * 24 * 3600;
-			else
-				goto err;
-		}
+		double time = parse_leasetime(c);
+		if (time < 0)
+			goto err;
 
 		if (time >= 60)
 			iface->dhcpv4_leasetime = time;
diff --git a/src/dhcpv4.c b/src/dhcpv4.c
index a657e13..f277a67 100644
--- a/src/dhcpv4.c
+++ b/src/dhcpv4.c
@@ -176,6 +176,8 @@ int setup_dhcpv4_interface(struct interface *iface, bool enable)
 					iface->ifname);
 				return -1;
 			}
+			if (lease->dhcpv4_leasetime >= 60)
+				a->leasetime = lease->dhcpv4_leasetime;
 			a->addr = ntohl(lease->ipaddr.s_addr);
 			memcpy(a->hwaddr, lease->mac.ether_addr_octet, sizeof(a->hwaddr));
 			memcpy(a->hostname, lease->hostname, hostlen);
@@ -382,13 +384,22 @@ static void handle_dhcpv4(void *addr, void *data, size_t len,
 	if (lease) {
 		reply.yiaddr.s_addr = htonl(lease->addr);
 
-		uint32_t val = htonl(iface->dhcpv4_leasetime);
+		uint32_t val;
+		uint32_t leasetime;
+
+		if (lease->leasetime >= 60) {
+			leasetime = lease->leasetime;
+		} else {
+			leasetime = iface->dhcpv4_leasetime;
+		}
+
+		val = htonl(leasetime);
 		dhcpv4_put(&reply, &cookie, DHCPV4_OPT_LEASETIME, 4, &val);
 
-		val = htonl(500 * iface->dhcpv4_leasetime / 1000);
+		val = htonl(500 * leasetime / 1000);
 		dhcpv4_put(&reply, &cookie, DHCPV4_OPT_RENEW, 4, &val);
 
-		val = htonl(875 * iface->dhcpv4_leasetime / 1000);
+		val = htonl(875 * leasetime / 1000);
 		dhcpv4_put(&reply, &cookie, DHCPV4_OPT_REBIND, 4, &val);
 
 		dhcpv4_put(&reply, &cookie, DHCPV4_OPT_NETMASK, 4, &ifnetmask.sin_addr);
@@ -622,10 +633,17 @@ static struct dhcpv4_assignment* dhcpv4_lease(struct interface *iface,
 			a->head.prev->next = &a->head;
 		}
 
+		uint32_t leasetime;
+		if (a->leasetime) {
+			leasetime = a->leasetime;
+		} else {
+			leasetime = iface->dhcpv4_leasetime;
+		}
+
 		// Was only a solicitation: mark binding for removal
 		if (assigned && a->valid_until < now) {
 			a->valid_until = (msg == DHCPV4_MSG_DISCOVER) ? 0 :
-					(now + iface->dhcpv4_leasetime);
+					(now + leasetime);
 		} else if (!assigned && a) { // Cleanup failed assignment
 			free(a);
 			a = NULL;
diff --git a/src/dhcpv4.h b/src/dhcpv4.h
index 6c72441..6c4dd50 100644
--- a/src/dhcpv4.h
+++ b/src/dhcpv4.h
@@ -78,6 +78,7 @@ struct dhcpv4_assignment {
 	uint32_t addr;
 	time_t valid_until;
 	uint8_t hwaddr[6];
+	uint32_t leasetime;
 	char hostname[];
 };
 
diff --git a/src/dhcpv6-ia.c b/src/dhcpv6-ia.c
index 9b8c479..4c321ac 100644
--- a/src/dhcpv6-ia.c
+++ b/src/dhcpv6-ia.c
@@ -100,6 +100,9 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
 				return -1;
 			}
 
+			if (lease->dhcpv4_leasetime > 0)
+				a->leasetime = lease->dhcpv4_leasetime;
+
 			a->clid_len = duid_len;
 			a->length = 128;
 			if (lease->hostid) {
@@ -675,7 +678,12 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
 		datalen += sizeof(stat);
 	} else {
 		if (a) {
-			uint32_t leasetime = iface->dhcpv4_leasetime;
+			uint32_t leasetime;
+			if (a->leasetime > 0) {
+				leasetime = a->leasetime;
+			} else {
+				leasetime = iface->dhcpv4_leasetime;
+			}
 			if (leasetime == 0)
 				leasetime = 3600;
 			else if (leasetime < 60)
diff --git a/src/dhcpv6.h b/src/dhcpv6.h
index d9f42c8..09ab46f 100644
--- a/src/dhcpv6.h
+++ b/src/dhcpv6.h
@@ -155,6 +155,8 @@ struct dhcpv6_assignment {
 	ssize_t managed_size;
 	struct ustream_fd managed_sock;
 
+	uint32_t leasetime;
+
 	uint8_t clid_len;
 	uint8_t clid_data[];
 };
diff --git a/src/odhcpd.h b/src/odhcpd.h
index fd43dfe..3e8fc3e 100644
--- a/src/odhcpd.h
+++ b/src/odhcpd.h
@@ -96,6 +96,7 @@ struct lease {
 	struct ether_addr mac;
 	uint16_t duid_len;
 	uint8_t *duid;
+	uint32_t dhcpv4_leasetime;
 	char hostname[];
 };