From: Roy Marples <roy@marples.name>
Date: Tue, 26 Nov 2019 19:57:30 +0000 (+0000)
Subject: DHCP: Improve API for privsep
X-Git-Tag: v8.1.3~15
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3bf57d1eb52fe05aec05cc7de2b6f6d6129e60a3;p=thirdparty%2Fdhcpcd.git

DHCP: Improve API for privsep
---

diff --git a/src/dhcp.c b/src/dhcp.c
index 73ab29e6..686aee44 100644
--- a/src/dhcp.c
+++ b/src/dhcp.c
@@ -1540,7 +1540,7 @@ dhcp_close(struct interface *ifp)
 }
 
 static int
-dhcp_openudp(struct interface *ifp)
+dhcp_openudp(struct in_addr *ia)
 {
 	int s;
 	struct sockaddr_in sin;
@@ -1551,29 +1551,25 @@ dhcp_openudp(struct interface *ifp)
 
 	n = 1;
 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &n, sizeof(n)) == -1)
-		goto eexit;
+		goto errexit;
 #ifdef IP_RECVIF
 	if (setsockopt(s, IPPROTO_IP, IP_RECVIF, &n, sizeof(n)) == -1)
-		goto eexit;
+		goto errexit;
 #else
 	if (setsockopt(s, IPPROTO_IP, IP_RECVPKTINFO, &n, sizeof(n)) == -1)
-		goto eexit;
+		goto errexit;
 #endif
 	memset(&sin, 0, sizeof(sin));
 	sin.sin_family = AF_INET;
 	sin.sin_port = htons(BOOTPC);
-	if (ifp) {
-		const struct dhcp_state *state = D_CSTATE(ifp);
-
-		if (state->addr)
-			sin.sin_addr.s_addr = state->addr->addr.s_addr;
-	}
+	if (ia != NULL)
+		sin.sin_addr = *ia;
 	if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) == -1)
-		goto eexit;
+		goto errexit;
 
 	return s;
 
-eexit:
+errexit:
 	close(s);
 	return -1;
 }
@@ -1675,7 +1671,7 @@ dhcp_sendudp(struct interface *ifp, struct in_addr *to, void *data, size_t len)
 
 	fd = state->udp_fd;
 	if (fd == -1) {
-		fd = dhcp_openudp(ifp);
+		fd = dhcp_openudp(state->addr != NULL ?&state->addr->addr:NULL);
 		if (fd == -1)
 			return -1;
 	}
@@ -1734,7 +1730,9 @@ send_message(struct interface *ifp, uint8_t type,
 		goto fail;
 	len = (size_t)r;
 
-	if (ipv4_iffindaddr(ifp, &state->lease.addr, NULL) != NULL)
+	if (!(state->added & STATE_FAKE) &&
+	    state->addr != NULL &&
+	    ipv4_iffindaddr(ifp, &state->lease.addr, NULL) != NULL)
 		from.s_addr = state->lease.addr.s_addr;
 	else
 		from.s_addr = INADDR_ANY;
@@ -2266,10 +2264,11 @@ dhcp_bind(struct interface *ifp)
 		return;
 	dhcp_close(ifp);
 
+
 	/* If not in master mode, open an address specific socket. */
 	if (ctx->udp_fd != -1)
 		return;
-	state->udp_fd = dhcp_openudp(ifp);
+	state->udp_fd = dhcp_openudp(&state->addr->addr);
 	if (state->udp_fd == -1) {
 		logerr(__func__);
 		/* Address sharing without master mode is not supported.
@@ -2352,6 +2351,7 @@ dhcp_arp_new(struct interface *ifp, struct in_addr *addr)
 #ifdef KERNEL_RFC5227
 	astate->announced_cb = dhcp_arp_announced;
 #else
+	astate->announced_cb = NULL;
 	astate->defend_failed_cb = dhcp_arp_defend_failed;
 #endif
 	return astate;
@@ -2501,7 +2501,7 @@ dhcp_inform(struct interface *ifp)
 			state->offer_len = dhcp_message_new(&state->offer,
 			    &ifo->req_addr, &ifo->req_mask);
 #ifdef ARP
-			if (dhcp_arp_address(ifp) == 0)
+			if (dhcp_arp_address(ifp) != 1)
 				return;
 #endif
 			ia = ipv4_iffindaddr(ifp,
@@ -3390,7 +3390,7 @@ dhcp_handlebootp(struct interface *ifp, struct bootp *bootp, size_t len,
 }
 
 static void
-dhcp_handlebpf(struct interface *ifp, uint8_t *data, size_t len)
+dhcp_packet(struct interface *ifp, uint8_t *data, size_t len)
 {
 	struct bootp *bootp;
 	struct in_addr from;
@@ -3445,7 +3445,7 @@ dhcp_readbpf(void *arg)
 			}
 			break;
 		}
-		dhcp_handlebpf(ifp, buf, (size_t)bytes);
+		dhcp_packet(ifp, buf, (size_t)bytes);
 		/* Check we still have a state after processing. */
 		if ((state = D_STATE(ifp)) == NULL)
 			break;