X-Git-Url: http://git.archive.openwrt.org/?p=project%2Fodhcpd.git;a=blobdiff_plain;f=src%2Fdhcpv4.c;h=0d7573011dba88379548ac4ab5bcfa223422b516;hp=b8d64ceaf7358c60bba1a6e3feaef6df90ecbfb3;hb=428908569b8da45613891e21736c587894e0c449;hpb=4267915aef64aae345972c77148b11759a172b14

diff --git a/src/dhcpv4.c b/src/dhcpv4.c
index b8d64ce..0d75730 100644
--- a/src/dhcpv4.c
+++ b/src/dhcpv4.c
@@ -34,7 +34,7 @@
 
 
 static void handle_dhcpv4(void *addr, void *data, size_t len,
-		struct interface *iface);
+		struct interface *iface, void *dest_addr);
 static struct dhcpv4_assignment* dhcpv4_lease(struct interface *iface,
 		enum dhcpv4_msg msg, const uint8_t *mac, struct in_addr reqaddr,
 		const char *hostname);
@@ -225,7 +225,7 @@ static void dhcpv4_put(struct dhcpv4_message *msg, uint8_t **cookie,
 
 // Simple DHCPv6-server for information requests
 static void handle_dhcpv4(void *addr, void *data, size_t len,
-		struct interface *iface)
+		struct interface *iface, _unused void *dest_addr)
 {
 	if (!iface->dhcpv4)
 		return;
@@ -334,7 +334,16 @@ static void handle_dhcpv4(void *addr, void *data, size_t len,
 	} else if (reqmsg == DHCPV4_MSG_REQUEST && reqaddr.s_addr &&
 			reqaddr.s_addr != htonl(lease->addr)) {
 		msg = DHCPV4_MSG_NAK;
-		lease = NULL;
+		/*
+		 * DHCP client requested an IP which we can't offer to him. Probably the
+		 * client changed the network. The reply type is set to DHCPV4_MSG_NAK,
+		 * because the client should not use that IP.
+		 *
+		 * For modern devices we build an answer that includes a valid IP, like
+		 * a DHCPV4_MSG_ACK. The client will use that IP and doesn't need to
+		 * perform additional DHCP round trips.
+		 *
+		 */
 	}
 
 	if (reqmsg == DHCPV4_MSG_DECLINE || reqmsg == DHCPV4_MSG_RELEASE)
@@ -491,7 +500,6 @@ static struct dhcpv4_assignment* dhcpv4_lease(struct interface *iface,
 		}
 	}
 
-	bool update_state = false;
 	if (msg == DHCPV4_MSG_DISCOVER || msg == DHCPV4_MSG_REQUEST) {
 		bool assigned = !!a;
 		size_t hostlen = strlen(hostname) + 1;
@@ -530,24 +538,18 @@ static struct dhcpv4_assignment* dhcpv4_lease(struct interface *iface,
 			a = NULL;
 		}
 
-		if (a)
-			update_state = true;
-
 		if (assigned && a)
 			lease = a;
 	} else if (msg == DHCPV4_MSG_RELEASE) {
 		if (a) {
 			a->valid_until = 0;
-			update_state = true;
 		}
 	} else if (msg == DHCPV4_MSG_DECLINE) {
 		memset(a->hwaddr, 0, sizeof(a->hwaddr));
 		a->valid_until = now + 3600; // Block address for 1h
-		update_state = true;
 	}
 
-	if (update_state)
-		dhcpv6_write_statefile();
+	dhcpv6_write_statefile();
 
 	return lease;
 }