Include PIPEX in kernel by default. And add new sysctl variable

`net.pipex.enable' to enable PIPEX.   By default, pipex is disabled
and it will not process packets from wire.  Update man pages and
update HOWTO_PIPEX_NPPPD.txt for testers.

discussed with dlg@, ok deraadt@ mcbride@ claudio@

3 files changed, 47 insertions, 9 deletions

diff --git a/sys/net/if_ethersubr.c b/sys/net/if_ethersubr.c
index d5b77eb20aa..0321a33726f 100644
--- a/sys/net/if_ethersubr.c
+++ b/sys/net/if_ethersubr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_ethersubr.c,v 1.149 2011/07/04 23:58:26 claudio Exp $	*/
+/*	$OpenBSD: if_ethersubr.c,v 1.150 2011/07/08 18:30:16 yasuoka Exp $	*/
 /*	$NetBSD: if_ethersubr.c,v 1.19 1996/05/07 02:40:30 thorpej Exp $	*/
 
 /*
@@ -750,14 +750,14 @@ decapsulate:
 		eh_tmp = mtod(m, struct ether_header *);
 		bcopy(eh, eh_tmp, sizeof(struct ether_header));
 #ifdef PIPEX
-	{
-		struct pipex_session *session;
+		if (pipex_enable) {
+			struct pipex_session *session;
 
-		if ((session = pipex_pppoe_lookup_session(m)) != NULL) {
-			pipex_pppoe_input(m, session);
-			goto done;
+			if ((session = pipex_pppoe_lookup_session(m)) != NULL) {
+				pipex_pppoe_input(m, session);
+				goto done;
+			}
 		}
-	}
 #endif
 		if (etype == ETHERTYPE_PPPOEDISC)
 			inq = &pppoediscinq;
diff --git a/sys/net/pipex.c b/sys/net/pipex.c
index 6ee41c1e46c..f5db7bf21e2 100644
--- a/sys/net/pipex.c
+++ b/sys/net/pipex.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pipex.c,v 1.18 2011/07/07 22:32:51 mcbride Exp $	*/
+/*	$OpenBSD: pipex.c,v 1.19 2011/07/08 18:30:17 yasuoka Exp $	*/
 
 /*-
  * Copyright (c) 2009 Internet Initiative Japan Inc.
@@ -36,6 +36,7 @@
 #include <sys/socket.h>
 #include <sys/ioctl.h>
 #include <sys/select.h>
+#include <sys/sysctl.h>
 #include <sys/syslog.h>
 #include <sys/conf.h>
 #include <sys/time.h>
@@ -84,6 +85,7 @@
 /*
  * static/global variables
  */
+int	pipex_enable = 0;
 struct pipex_hash_head
     pipex_session_list,				/* master session list */
     pipex_close_wait_list,			/* expired session list */
@@ -2978,3 +2980,21 @@ pipex_sockaddr_compar_addr(struct sockaddr *a, struct sockaddr *b)
 	panic("pipex_sockaddr_compar_addr: unknown address family");
 	return -1;
 }
+
+int
+pipex_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
+    size_t newlen)
+{
+	/* All sysctl names at this level are terminal. */
+	if (namelen != 1)
+		return (ENOTDIR);
+
+	switch (name[0]) {
+	case PIPEXCTL_ENABLE:
+		return (sysctl_int(oldp, oldlenp, newp, newlen,
+		    &pipex_enable));
+	default:
+		return (ENOPROTOOPT);
+	}
+	/* NOTREACHED */
+}
diff --git a/sys/net/pipex.h b/sys/net/pipex.h
index 063ea59e596..391e69ea54d 100644
--- a/sys/net/pipex.h
+++ b/sys/net/pipex.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pipex.h,v 1.8 2011/04/02 11:52:44 dlg Exp $	*/
+/*	$OpenBSD: pipex.h,v 1.9 2011/07/08 18:30:17 yasuoka Exp $	*/
 
 /*
  * Copyright (c) 2009 Internet Initiative Japan Inc.
@@ -29,6 +29,23 @@
 #ifndef NET_PIPEX_H
 #define NET_PIPEX_H 1
 
+/*
+ * Names for pipex sysctl objects
+ */
+#define PIPEXCTL_ENABLE		1
+#define PIPEXCTL_MAXID		2
+
+#define PIPEXCTL_NAMES { \
+        { 0, 0 }, \
+        { "enable", CTLTYPE_INT }, \
+}
+
+#define PIPEXCTL_VARS { \
+	NULL, \
+	&pipex_enable \
+	NULL \
+}
+
 #define PIPEX_ENABLE			1
 #define PIPEX_DISABLE			0
 
@@ -163,6 +180,7 @@ struct pipex_session_descr_req {
 #define PIPEXSIFDESCR	_IOW ('p',  8, struct pipex_session_descr_req)
 
 #ifdef _KERNEL
+extern int	pipex_enable;
 
 struct pipex_session;