From: mvs <mvs@openbsd.org>
Date: Thu, 22 Aug 2024 10:58:31 +0000 (+0000)
Subject: Unlock unlock ipip_sysctl().
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=7af0f08f590ac7f13ecd0047a3d6943230ee3df9;p=openbsd

Unlock unlock ipip_sysctl().

- IPIPCTL_ALLOW - atomically accessed integer;
- IPIPCTL_STATS - per-CPU counters;

In ipip_input() load `ipip_allow' value to `ipip_allow_local' and pass
it down to ipip_input_if() as `allow' arg.

ok bluhm
---

diff --git a/sys/netinet/in_proto.c b/sys/netinet/in_proto.c
index cd64f177724..80889ddfbac 100644
--- a/sys/netinet/in_proto.c
+++ b/sys/netinet/in_proto.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: in_proto.c,v 1.112 2024/08/21 12:53:36 mvs Exp $	*/
+/*	$OpenBSD: in_proto.c,v 1.113 2024/08/22 10:58:31 mvs Exp $	*/
 /*	$NetBSD: in_proto.c,v 1.14 1996/02/18 18:58:32 christos Exp $	*/
 
 /*
@@ -230,7 +230,7 @@ const struct protosw inetsw[] = {
   .pr_type	= SOCK_RAW,
   .pr_domain	= &inetdomain,
   .pr_protocol	= IPPROTO_IPV4,
-  .pr_flags	= PR_ATOMIC|PR_ADDR|PR_MPSOCKET,
+  .pr_flags	= PR_ATOMIC|PR_ADDR|PR_MPSOCKET|PR_MPSYSCTL,
 #if NGIF > 0
   .pr_input	= in_gif_input,
 #else
diff --git a/sys/netinet/ip_ipip.c b/sys/netinet/ip_ipip.c
index 67434ca1fb1..cce51da22d0 100644
--- a/sys/netinet/ip_ipip.c
+++ b/sys/netinet/ip_ipip.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_ipip.c,v 1.104 2024/08/21 12:53:36 mvs Exp $ */
+/*	$OpenBSD: ip_ipip.c,v 1.105 2024/08/22 10:58:31 mvs Exp $ */
 /*
  * The authors of this code are John Ioannidis (ji@tla.org),
  * Angelos D. Keromytis (kermit@csd.uch.gr) and
@@ -72,6 +72,11 @@
 #include <net/pfvar.h>
 #endif
 
+/*
+ * Locks used to protect data:
+ *	a	atomic
+ */
+
 #ifdef ENCDEBUG
 #define DPRINTF(fmt, args...)						\
 	do {								\
@@ -87,7 +92,7 @@
  * We can control the acceptance of IP4 packets by altering the sysctl
  * net.inet.ipip.allow value.  Zero means drop them, all else is acceptance.
  */
-int ipip_allow = 0;
+int ipip_allow = 0;	/* [a] */
 
 struct cpumem *ipipcounters;
 
@@ -104,9 +109,10 @@ int
 ipip_input(struct mbuf **mp, int *offp, int nxt, int af)
 {
 	struct ifnet *ifp;
+	int ipip_allow_local = atomic_load_int(&ipip_allow);
 
 	/* If we do not accept IP-in-IP explicitly, drop.  */
-	if (!ipip_allow && ((*mp)->m_flags & (M_AUTH|M_CONF)) == 0) {
+	if (ipip_allow_local == 0 && ((*mp)->m_flags & (M_AUTH|M_CONF)) == 0) {
 		DPRINTF("dropped due to policy");
 		ipipstat_inc(ipips_pdrops);
 		m_freemp(mp);
@@ -118,7 +124,7 @@ ipip_input(struct mbuf **mp, int *offp, int nxt, int af)
 		m_freemp(mp);
 		return IPPROTO_DONE;
 	}
-	nxt = ipip_input_if(mp, offp, nxt, af, ifp);
+	nxt = ipip_input_if(mp, offp, nxt, af, ipip_allow_local, ifp);
 	if_put(ifp);
 
 	return nxt;
@@ -133,7 +139,7 @@ ipip_input(struct mbuf **mp, int *offp, int nxt, int af)
  */
 
 int
-ipip_input_if(struct mbuf **mp, int *offp, int proto, int oaf,
+ipip_input_if(struct mbuf **mp, int *offp, int proto, int oaf, int allow,
     struct ifnet *ifp)
 {
 	struct mbuf *m = *mp;
@@ -271,7 +277,7 @@ ipip_input_if(struct mbuf **mp, int *offp, int proto, int oaf,
 	}
 
 	/* Check for local address spoofing. */
-	if (!(ifp->if_flags & IFF_LOOPBACK) && ipip_allow != 2) {
+	if (!(ifp->if_flags & IFF_LOOPBACK) && allow != 2) {
 		struct sockaddr_storage ss;
 		struct rtentry *rt;
 
@@ -584,19 +590,14 @@ int
 ipip_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
     size_t newlen)
 {
-	int error;
-
 	/* All sysctl names at this level are terminal. */
 	if (namelen != 1)
 		return (ENOTDIR);
 
 	switch (name[0]) {
 	case IPIPCTL_ALLOW:
-		NET_LOCK();
-		error = sysctl_int_bounded(oldp, oldlenp, newp, newlen,
-		    &ipip_allow, 0, 2);
-		NET_UNLOCK();
-		return (error);
+		return (sysctl_int_bounded(oldp, oldlenp, newp, newlen,
+		    &ipip_allow, 0, 2));
 	case IPIPCTL_STATS:
 		return (ipip_sysctl_ipipstat(oldp, oldlenp, newp));
 	default:
diff --git a/sys/netinet/ip_ipip.h b/sys/netinet/ip_ipip.h
index f9d04498444..adf4221998b 100644
--- a/sys/netinet/ip_ipip.h
+++ b/sys/netinet/ip_ipip.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_ipip.h,v 1.13 2021/10/13 14:36:31 bluhm Exp $ */
+/*	$OpenBSD: ip_ipip.h,v 1.14 2024/08/22 10:58:31 mvs Exp $ */
 /*
  * The authors of this code are John Ioannidis (ji@tla.org),
  * Angelos D. Keromytis (kermit@csd.uch.gr) and
@@ -114,7 +114,7 @@ struct tdb;
 
 void	ipip_init(void);
 int	ipip_input(struct mbuf **, int *, int, int);
-int	ipip_input_if(struct mbuf **, int *, int, int, struct ifnet *);
+int	ipip_input_if(struct mbuf **, int *, int, int, int, struct ifnet *);
 int	ipip_output(struct mbuf **, struct tdb *);
 int	ipip_sysctl(int *, u_int, void *, size_t *, void *, size_t);