From 6ca5a4e867e564926b5d64667f9c63078fb63ccf Mon Sep 17 00:00:00 2001
From: Roy Marples <roy@marples.name>
Date: Thu, 19 May 2016 15:10:26 +0000
Subject: [PATCH] Provide a better getifaddrs(3).

---
 if-sun.c | 30 ++++++++++++++++++++++++------
 if.c     | 15 ++-------------
 if.h     |  4 +++-
 3 files changed, 29 insertions(+), 20 deletions(-)

diff --git a/if-sun.c b/if-sun.c
index 33ce9ab7..7b49bde9 100644
--- a/if-sun.c
+++ b/if-sun.c
@@ -37,6 +37,10 @@
 
 #include <inet/ip.h>
 
+/* private interface we can hook into to get
+ * a better getifaddrs(3). */
+#include <libsocket_priv.h>
+
 #include <net/if_dl.h>
 #include <net/if_types.h>
 
@@ -192,6 +196,7 @@ if_newaddr(const char *ifname, void *arg)
 		goto failed;
 
 	ifa->ifa_addr = (struct sockaddr *)sdl;
+	sdl->sdl_index = if_nametoindex(ifname);
 	sdl->sdl_family = AF_LINK;
 	switch (dlinfo.di_mactype) {
 	case DL_ETHER:
@@ -247,20 +252,26 @@ if_ifa_lo0(void)
 	ifa->ifa_addr = (struct sockaddr *)sdl;
 	ifa->ifa_flags = IFF_LOOPBACK;
 	sdl->sdl_family = AF_LINK;
+	sdl->sdl_index = if_nametoindex("lo0");
 
 	return ifa;
 }
 
-/* all getifaddrs(3) should support AF_LINK, but hey ho */
+/* getifaddrs(3) does not support AF_LINK, strips aliases and won't
+ * report addresses that are not UP.
+ * As such it's just totally useless, so we need to roll our own. */
 int
 if_getifaddrs(struct ifaddrs **ifap)
 {
 	struct linkwalk		lw;
+	struct ifaddrs		*ifa;
 
-	/* lo0 doesn't appear in dlpi_walk, so fudge it. */
-	if ((lw.lw_ifa = if_ifa_lo0()) == NULL)
+	/* Private libc function which we should not have to call
+	 * to get non UP addresses. */
+	if (getallifaddrs(AF_UNSPEC, &lw.lw_ifa, 0) == -1)
 		return -1;
 
+	/* Start with some AF_LINK addresses. */
 	lw.lw_error = 0;
 	dlpi_walk(if_newaddr, &lw, 0);
 	if (lw.lw_error != 0) {
@@ -269,7 +280,14 @@ if_getifaddrs(struct ifaddrs **ifap)
 		return -1;
 	}
 
-	*ifap = lw.lw_ifa;
+	/* lo0 doesn't appear in dlpi_walk, so fudge it. */
+	if ((ifa = if_ifa_lo0()) == NULL) {
+		freeifaddrs(lw.lw_ifa);
+		return -1;
+	}
+	ifa->ifa_next = lw.lw_ifa;
+
+	*ifap = ifa;
 	return 0;
 }
 
@@ -546,7 +564,7 @@ if_readraw(struct interface *ifp, int fd,
 }
 
 int
-if_address(unsigned char cmd, struct ipv4_addr *ia)
+if_address(unsigned char cmd, const struct ipv4_addr *ia)
 {
 
 	UNUSED(cmd);
@@ -645,7 +663,7 @@ if_address6(unsigned char cmd, const struct ipv6_addr *ia)
 {
 
 	UNUSED(cmd);
-	UNUSED(action);
+	UNUSED(ia);
 	errno = ENOTSUP;
 	return -1;
 }
diff --git a/if.c b/if.c
index 99ac3ca5..67f04043 100644
--- a/if.c
+++ b/if.c
@@ -270,13 +270,9 @@ if_discover(struct dhcpcd_ctx *ctx, int argc, char * const *argv)
 	const struct sockaddr_ll *sll;
 #endif
 
-#ifdef GETIFADDRS_AFLINK
-	if (getifaddrs(&ifaddrs) == -1)
-		return NULL;
-#else
 	if (if_getifaddrs(&ifaddrs) == -1)
 		return NULL;
-#endif
+
 	ifs = malloc(sizeof(*ifs));
 	if (ifs == NULL)
 		return NULL;
@@ -553,15 +549,8 @@ if_discover(struct dhcpcd_ctx *ctx, int argc, char * const *argv)
 		TAILQ_INSERT_TAIL(ifs, ifp, next);
 	}
 
-#ifdef GETIFADDRS_AFLINK
-	{
-#else
+	if_learnaddrs(ctx, ifs, ifaddrs);
 	freeifaddrs(ifaddrs);
-	if (getifaddrs(&ifaddrs) != -1) {
-#endif
-		if_learnaddrs(ctx, ifs, ifaddrs);
-		freeifaddrs(ifaddrs);
-	}
 
 	return ifs;
 }
diff --git a/if.h b/if.h
index 078cc8ad..ab4bb3c1 100644
--- a/if.h
+++ b/if.h
@@ -83,9 +83,11 @@
 #define RAW_PARTIALCSUM		1 << 0
 
 #ifdef __sun
-/* platform does not supply AF_LINK with getifaddrs. */
+/* Solaris getifaddrs is very un-suitable for dhcpcd.
+ * See if-sun.c for details why. */
 struct ifaddrs;
 int if_getifaddrs(struct ifaddrs **);
+#define	getifaddrs	if_getaddrs
 #else
 #define GETIFADDRS_AFLINK
 #endif
-- 
2.47.3