From: Jin-Seong Kim <jseong82.kim@samsung.com>
Date: Thu, 25 May 2017 08:30:55 +0000 (+0900)
Subject: netutils/dhcpc : do not send decline message to same dhcp server
X-Git-Tag: 1.1_Public_Release~457^2~13
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=97ac4d053296eddef1d358baceea4cc2a809ad0b;p=rtos%2Ftinyara.git

netutils/dhcpc : do not send decline message to same dhcp server

This commit is bug fix to prevent send decline message
 - dhcp declient message is used to announce duplicated
   assigned IP address in a network
 - dhcp client doesn't have routine to check duplicate IP
   via ARP, so no need to send decline message to same server

Change-Id: Iae6036e064d767159fa6d1b6a10f95fcaa3c317f
Signed-off-by: Jin-Seong Kim <jseong82.kim@samsung.com>
---

diff --git a/apps/netutils/dhcpc/dhcpc.c b/apps/netutils/dhcpc/dhcpc.c
index 354a0f1..6b8cac0 100644
--- a/apps/netutils/dhcpc/dhcpc.c
+++ b/apps/netutils/dhcpc/dhcpc.c
@@ -592,10 +592,15 @@ int dhcpc_request(void *handle, struct dhcpc_state *presult)
 		 */
 
 		else if (msgtype == DHCPOFFER) {
-			ndbg("Received another OFFER, send DECLINE\n");
-			result = dhcpc_sendmsg(pdhcpc, presult, DHCPDECLINE);
-			if (result <= 0) {
-				ndbg("recv request error(%d)(%d)\n", result, errno);
+			/* If we get OFFERs from same dhcp server, do not send DECLINE */
+			if (pdhcpc->serverid.s_addr == presult->serverid.s_addr) {
+				ndbg("Received duplicated OFFER from %08x\n", ntohl(presult->serverid.s_addr));
+			} else {
+				ndbg("Received another OFFER from %08x, send DECLINE\n", ntohl(presult->serverid.s_addr));
+				result = dhcpc_sendmsg(pdhcpc, presult, DHCPDECLINE);
+				if (result <= 0) {
+					ndbg("recv request error(%d)(%d)\n", result, errno);
+				}
 			}
 		}