interfaces: detect IPv6 ULA & link-local addresses

Update nice_interfaces_is_private_ip() to handle IPv6 too:

- unique local address block: fc00::/7
- link-local address block:   fe80::/10

diff --git a/agent/interfaces.c b/agent/interfaces.c
index 0dc4b0d..f8bb086 100644 (file)
--- a/agent/interfaces.c
+++ b/agent/interfaces.c
@@ -193,6 +193,7 @@ nice_interfaces_is_private_ip (const struct sockaddr *_sa)
   union {
     const struct sockaddr *addr;
     const struct sockaddr_in *in;
+    const struct sockaddr_in6 *in6;
   } sa;
 
   sa.addr = _sa;
@@ -213,6 +214,15 @@ nice_interfaces_is_private_ip (const struct sockaddr *_sa)
     /* 169.254.x.x/16  (for APIPA) */
     if (sa.in->sin_addr.s_addr >> 16 == 0xA9FE)
       return TRUE;
+  } else if (sa.addr->sa_family == AF_INET6) {
+    /* fc00::/7 Unique local address (ULA) */
+    if ((sa.in6->sin6_addr.s6_addr[0] & 0xFE) == 0xFC)
+      return TRUE;
+
+    /* fe80::/10 link-local address */
+    if ( (sa.in6->sin6_addr.s6_addr[0]         == 0xFE)  &&
+        ((sa.in6->sin6_addr.s6_addr[1] & 0xC0) == 0x80))
+      return TRUE;
   }
   
   return FALSE;