From d705c979f018e29f2ecba822ca229827efb9e95c Mon Sep 17 00:00:00 2001
From: Roy Marples <roy@marples.name>
Date: Mon, 5 Mar 2012 10:04:26 +0000
Subject: [PATCH] Respect an accept_ra setting of 2, fixes #240. Detect IPv6
 settings per interface if the platform allows, fixed #241.

---
 dhcpcd.c         | 10 +++++++---
 platform-bsd.c   |  6 +++++-
 platform-linux.c | 28 +++++++++++++++++++++-------
 platform.h       |  4 ++--
 4 files changed, 35 insertions(+), 13 deletions(-)

diff --git a/dhcpcd.c b/dhcpcd.c
index 6b8382bc..0f71e4a6 100644
--- a/dhcpcd.c
+++ b/dhcpcd.c
@@ -1162,8 +1162,12 @@ start_interface(void *arg)
 	free(iface->state->offer);
 	iface->state->offer = NULL;
 
-	if (options & DHCPCD_IPV6RS && ifo->options & DHCPCD_IPV6RS)
-		ipv6rs_start(iface);
+	if (options & DHCPCD_IPV6RS && ifo->options & DHCPCD_IPV6RS) {
+		if (check_ipv6(iface->name) == 1)
+			ipv6rs_start(iface);
+		else
+			ifo->options &= ~DHCPCD_IPV6RS;
+	}
 
 	if (iface->state->arping_index < ifo->arping_len) {
 		start_arping(iface);
@@ -1993,7 +1997,7 @@ main(int argc, char **argv)
 	}
 #endif
 
-	if (options & DHCPCD_IPV6RS && !check_ipv6())
+	if (options & DHCPCD_IPV6RS && !check_ipv6(NULL))
 		options &= ~DHCPCD_IPV6RS;
 	if (options & DHCPCD_IPV6RS) {
 		ipv6rsfd = ipv6rs_open();
diff --git a/platform-bsd.c b/platform-bsd.c
index 6fb1896c..afa43845 100644
--- a/platform-bsd.c
+++ b/platform-bsd.c
@@ -68,9 +68,13 @@ inet6_sysctl(int code)
 }
 
 int
-check_ipv6(void)
+check_ipv6(const char *ifname)
 {
 
+	/* BSD doesn't support these values per iface, so just reutrn 1 */
+	if (ifname)
+		return 1;
+
 	if (inet6_sysctl(IPV6CTL_ACCEPT_RTADV) != 1) {
 		syslog(LOG_WARNING,
 		    "Kernel is not configured to accept IPv6 RAs");
diff --git a/platform-linux.c b/platform-linux.c
index e2d2844b..119ec501 100644
--- a/platform-linux.c
+++ b/platform-linux.c
@@ -121,19 +121,33 @@ check_proc_int(const char *path)
 	return atoi(buf);
 }
 
+static const char *prefix = "/proc/sys/net/ipv6/conf";
+
 int
-check_ipv6(void)
+check_ipv6(const char *ifname)
 {
+	int r;
+	char path[256];
+
+	if (ifname == NULL)
+		ifname = "all";
 
-	if (check_proc_int("/proc/sys/net/ipv6/conf/all/accept_ra") != 1) {
+	snprintf(path, sizeof(path), "%s/%s/accept_ra", prefix, ifname);
+	r = check_proc_int(path);
+	if (r != 1 && r != 2) {
 		syslog(LOG_WARNING,
-		    "Kernel is not configured to accept IPv6 RAs");
+		    "%s: not configured to accept IPv6 RAs", ifname);
 		return 0;
 	}
-	if (check_proc_int("/proc/sys/net/ipv6/conf/all/forwarding") != 0) {
-		syslog(LOG_WARNING,
-		    "Kernel is configured as a router, not a host");
-		return 0;
+
+	if (r != 2) {
+		snprintf(path, sizeof(path), "%s/%s/forwarding",
+		    prefix, ifname);
+		if (check_proc_int(path) != 0) {
+			syslog(LOG_WARNING,
+			    "%s: configured as a router, not a host", ifname);
+			return 0;
+		}
 	}
 	return 1;
 }
diff --git a/platform.h b/platform.h
index 1286fe62..08ec368a 100644
--- a/platform.h
+++ b/platform.h
@@ -28,7 +28,7 @@
 #ifndef PLATFORM_H
 #define PLATFORM_H
 
-char * hardware_platform(void);
-int check_ipv6(void);
+char *hardware_platform(void);
+int check_ipv6(const char *);
 
 #endif
-- 
2.47.2