Probe for the availability of AF_INET6 at startup. If it's not

available, default ipv6cp to disabled and refuse to let the user
enable it.

1 files changed, 26 insertions, 3 deletions

diff --git a/usr.sbin/ppp/probe.c b/usr.sbin/ppp/probe.c
index 0b6b617..4cca3cb 100644
--- a/usr.sbin/ppp/probe.c
+++ b/usr.sbin/ppp/probe.c
@@ -27,11 +27,15 @@
  */
 
 #include <sys/time.h>
+#include <sys/socket.h>
+
 #include <unistd.h>
 
 #include "probe.h"
 #include "log.h"
 
+struct probe probe;
+
 /* Does select() alter the passed time value ? */
 static int
 select_changes_time(void)
@@ -44,10 +48,29 @@ select_changes_time(void)
   return t.tv_usec != 100000;
 }
 
+#ifndef NOINET6
+static int
+ipv6_available(void)
+{
+  int s;
+
+  if ((s = ID0socket(AF_INET6, SOCK_DGRAM, 0)) == -1)
+    return 0;
+
+  close(s);
+  return 1;
+}
+#endif
+
 void
-probe_Init(struct probe *p)
+probe_Init()
 {
-  p->select_changes_time = select_changes_time() ? 1 : 0;
+  probe.select_changes_time = select_changes_time() ? 1 : 0;
   log_Printf(LogDEBUG, "Select changes time: %s\n",
-             p->select_changes_time ? "yes" : "no");
+             probe.select_changes_time ? "yes" : "no");
+#ifndef NOINET6
+  probe.ipv6_available = ipv6_available() ? 1 : 0;
+  log_Printf(LogDEBUG, "IPv6 available: %s\n",
+             probe.ipv6_available ? "yes" : "no");
+#endif
 }