From: Roy Marples <roy@marples.name>
Date: Sat, 13 Dec 2014 13:35:18 +0000 (+0000)
Subject: The noalias directive will now remove any IPv4 addresses existing on
X-Git-Tag: v6.6.6~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dffe72f6a66611bfd280efaa10465b91bd0d41a4;p=thirdparty%2Fdhcpcd.git

The noalias directive will now remove any IPv4 addresses existing on
the interface when we want to add our own.
---

diff --git a/dhcpcd.conf.5.in b/dhcpcd.conf.5.in
index 93e74e2b..d721fc41 100644
--- a/dhcpcd.conf.5.in
+++ b/dhcpcd.conf.5.in
@@ -22,7 +22,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd October 3, 2014
+.Dd December 13, 2014
 .Dt DHCPCD.CONF 5
 .Os
 .Sh NAME
@@ -376,8 +376,8 @@ will supply a default metric of 200 +
 .Xr if_nametoindex 3 .
 An extra 100 will be added for wireless interfaces.
 .It Ic noalias
-IPv4 addresses added will overwrite a pre-existing address instead of working
-alongside.
+Any pre-existing IPv4 addresses existing address will be removed from the
+interface when adding a new IPv4 address.
 .It Ic noarp
 Don't send any ARP requests.
 This also disables IPv4LL.
diff --git a/if-bsd.c b/if-bsd.c
index 728228c3..6a9ddc1e 100644
--- a/if-bsd.c
+++ b/if-bsd.c
@@ -46,6 +46,7 @@
 #include <net/route.h>
 #include <netinet/if_ether.h>
 #include <netinet/in.h>
+#include <netinet/in_var.h>
 #include <netinet6/in6_var.h>
 #include <netinet6/nd6.h>
 #ifdef __DragonFly__
@@ -418,40 +419,32 @@ next:
 }
 
 int
-if_address(const struct interface *iface, const struct in_addr *address,
+if_address(const struct interface *ifp, const struct in_addr *address,
     const struct in_addr *netmask, const struct in_addr *broadcast,
     int action)
 {
 	int s, r;
-	struct ifaliasreq ifa;
-	union {
-		struct sockaddr *sa;
-		struct sockaddr_in *sin;
-	} _s;
+	struct in_aliasreq ifra;
 
 	if ((s = socket(PF_INET, SOCK_DGRAM, 0)) == -1)
 		return -1;
 
-	memset(&ifa, 0, sizeof(ifa));
-	strlcpy(ifa.ifra_name, iface->name, sizeof(ifa.ifra_name));
-
-#define ADDADDR(_var, _addr) {						      \
-		_s.sa = &_var;						      \
-		_s.sin->sin_family = AF_INET;				      \
-		_s.sin->sin_len = sizeof(*_s.sin);			      \
-		memcpy(&_s.sin->sin_addr, _addr, sizeof(_s.sin->sin_addr));   \
-	}
-
-	ADDADDR(ifa.ifra_addr, address);
-	ADDADDR(ifa.ifra_mask, netmask);
-	if (action >= 0 && broadcast) {
-		ADDADDR(ifa.ifra_broadaddr, broadcast);
-	}
+	memset(&ifra, 0, sizeof(ifra));
+	strlcpy(ifra.ifra_name, ifp->name, sizeof(ifra.ifra_name));
+
+#define ADDADDR(var, addr) do {						      \
+		(var)->sin_family = AF_INET;				      \
+		(var)->sin_len = sizeof(*(var));			      \
+		(var)->sin_addr = *(addr);				      \
+	} while (/*CONSTCOND*/0)
+	ADDADDR(&ifra.ifra_addr, address);
+	ADDADDR(&ifra.ifra_mask, netmask);
+	if (action >= 0 && broadcast)
+		ADDADDR(&ifra.ifra_broadaddr, broadcast);
 #undef ADDADDR
 
 	r = ioctl(s,
-	    action < 0 ? SIOCDIFADDR :
-	    action == 2 ? SIOCSIFADDR :  SIOCAIFADDR, &ifa);
+	    action < 0 ? SIOCDIFADDR : SIOCAIFADDR, &ifra);
 	close(s);
 	return r;
 }
diff --git a/if.h b/if.h
index 4f874cb4..6df69674 100644
--- a/if.h
+++ b/if.h
@@ -111,12 +111,10 @@ ssize_t if_readrawpacket(struct interface *, int, void *, size_t, int *);
 int if_address(const struct interface *,
     const struct in_addr *, const struct in_addr *,
     const struct in_addr *, int);
-#define if_addaddress(iface, addr, net, brd)				      \
-	if_address(iface, addr, net, brd, 1)
-#define if_setaddress(iface, addr, net, brd)				      \
-	if_address(iface, addr, net, brd, 2)
-#define if_deladdress(iface, addr, net)				      \
-	if_address(iface, addr, net, NULL, -1)
+#define if_addaddress(ifp, addr, net, brd)	\
+	if_address(ifp, addr, net, brd, 1)
+#define if_deladdress(ifp, addr, net)		\
+	if_address(ifp, addr, net, NULL, -1)
 
 int if_route(const struct rt *rt, int);
 #define if_addroute(rt) if_route(rt, 1)
diff --git a/ipv4.c b/ipv4.c
index 0d3c74f3..d22e77ac 100644
--- a/ipv4.c
+++ b/ipv4.c
@@ -729,19 +729,25 @@ ipv4_getstate(struct interface *ifp)
 }
 
 static int
-ipv4_addaddr(const struct interface *ifp, const struct dhcp_lease *lease)
+ipv4_addaddr(struct interface *ifp, const struct dhcp_lease *lease)
 {
 	int r;
 
+	if (ifp->options->options & DHCPCD_NOALIAS) {
+		struct ipv4_state *state;
+		struct ipv4_addr *ap, *apn;
+
+		state = IPV4_STATE(ifp);
+		TAILQ_FOREACH_SAFE(ap, &state->addrs, next, apn) {
+			if (ap->addr.s_addr != lease->addr.s_addr)
+				delete_address1(ifp, &ap->addr, &ap->net);
+		}
+	}
+
 	syslog(LOG_DEBUG, "%s: adding IP address %s/%d",
 	    ifp->name, inet_ntoa(lease->addr),
 	    inet_ntocidr(lease->net));
-	if (ifp->options->options & DHCPCD_NOALIAS)
-		r = if_setaddress(ifp,
-		    &lease->addr, &lease->net, &lease->brd);
-	else
-		r = if_addaddress(ifp,
-		    &lease->addr, &lease->net, &lease->brd);
+	r = if_addaddress(ifp, &lease->addr, &lease->net, &lease->brd);
 	if (r == -1 && errno != EEXIST)
 		syslog(LOG_ERR, "%s: if_addaddress: %m", __func__);
 	return r;
@@ -868,7 +874,8 @@ ipv4_applyaddr(void *arg)
 
 	/* Now delete the old address if different */
 	if (state->addr.s_addr != lease->addr.s_addr &&
-	    state->addr.s_addr != 0)
+	    state->addr.s_addr != 0 &&
+	    ipv4_iffindaddr(ifp, &lease->addr, NULL))
 		delete_address(ifp);
 
 	state->added = STATE_ADDED;