1 files changed, 167 insertions, 43 deletions

diff --git a/freebsd/sys/netpfil/ipfw/ip_fw_pfil.c b/freebsd/sys/netpfil/ipfw/ip_fw_pfil.c
index d2e1b448..59c13aa5 100644
--- a/freebsd/sys/netpfil/ipfw/ip_fw_pfil.c
+++ b/freebsd/sys/netpfil/ipfw/ip_fw_pfil.c
@@ -49,6 +49,7 @@ __FBSDID("$FreeBSD$");
 
 #include <net/if.h>
 #include <net/route.h>
+#include <net/ethernet.h>
 #include <net/pfil.h>
 #include <net/vnet.h>
 
@@ -60,6 +61,7 @@ __FBSDID("$FreeBSD$");
 #ifdef INET6
 #include <netinet/ip6.h>
 #include <netinet6/ip6_var.h>
+#include <netinet6/scope6_var.h>
 #endif
 
 #include <netgraph/ng_ipfw.h>
@@ -76,26 +78,39 @@ static VNET_DEFINE(int, fw6_enable) = 1;
 #define V_fw6_enable	VNET(fw6_enable)
 #endif
 
+static VNET_DEFINE(int, fwlink_enable) = 0;
+#define V_fwlink_enable	VNET(fwlink_enable)
+
 int ipfw_chg_hook(SYSCTL_HANDLER_ARGS);
 
 /* Forward declarations. */
 static int ipfw_divert(struct mbuf **, int, struct ipfw_rule_ref *, int);
+int ipfw_check_packet(void *, struct mbuf **, struct ifnet *, int,
+	struct inpcb *);
+int ipfw_check_frame(void *, struct mbuf **, struct ifnet *, int,
+	struct inpcb *);
 
 #ifdef SYSCTL_NODE
 
 SYSBEGIN(f1)
 
 SYSCTL_DECL(_net_inet_ip_fw);
-SYSCTL_VNET_PROC(_net_inet_ip_fw, OID_AUTO, enable,
-    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw_enable), 0,
-    ipfw_chg_hook, "I", "Enable ipfw");
+SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, enable,
+    CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3,
+    &VNET_NAME(fw_enable), 0, ipfw_chg_hook, "I", "Enable ipfw");
 #ifdef INET6
 SYSCTL_DECL(_net_inet6_ip6_fw);
-SYSCTL_VNET_PROC(_net_inet6_ip6_fw, OID_AUTO, enable,
-    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw6_enable), 0,
-    ipfw_chg_hook, "I", "Enable ipfw+6");
+SYSCTL_PROC(_net_inet6_ip6_fw, OID_AUTO, enable,
+    CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3,
+    &VNET_NAME(fw6_enable), 0, ipfw_chg_hook, "I", "Enable ipfw+6");
 #endif /* INET6 */
 
+SYSCTL_DECL(_net_link_ether);
+SYSCTL_PROC(_net_link_ether, OID_AUTO, ipfw,
+    CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3,
+    &VNET_NAME(fwlink_enable), 0, ipfw_chg_hook, "I",
+    "Pass ether pkts through firewall");
+
 SYSEND
 
 #endif /* SYSCTL_NODE */
@@ -106,7 +121,7 @@ SYSEND
  * The packet may be consumed.
  */
 int
-ipfw_check_hook(void *arg, struct mbuf **m0, struct ifnet *ifp, int dir,
+ipfw_check_packet(void *arg, struct mbuf **m0, struct ifnet *ifp, int dir,
     struct inpcb *inp)
 {
 	struct ip_fw_args args;
@@ -114,10 +129,6 @@ ipfw_check_hook(void *arg, struct mbuf **m0, struct ifnet *ifp, int dir,
 	int ipfw;
 	int ret;
 
-	/* all the processing now uses ip_len in net format */
-	if (mtod(*m0, struct ip *)->ip_v == 4)
-		SET_NET_IPLEN(mtod(*m0, struct ip *));
-
 	/* convert dir to IPFW values */
 	dir = (dir == PFIL_IN) ? DIR_IN : DIR_OUT;
 	bzero(&args, sizeof(args));
@@ -131,11 +142,8 @@ again:
 	if (tag != NULL) {
 		args.rule = *((struct ipfw_rule_ref *)(tag+1));
 		m_tag_delete(*m0, tag);
-		if (args.rule.info & IPFW_ONEPASS) {
-			if (mtod(*m0, struct ip *)->ip_v == 4)
-				SET_HOST_IPLEN(mtod(*m0, struct ip *));
+		if (args.rule.info & IPFW_ONEPASS)
 			return (0);
-		}
 	}
 
 	args.m = *m0;
@@ -192,8 +200,20 @@ again:
 		}
 #ifdef INET6
 		if (args.next_hop6 != NULL) {
-			bcopy(args.next_hop6, (fwd_tag+1), len);
-			if (in6_localip(&args.next_hop6->sin6_addr))
+			struct sockaddr_in6 *sa6;
+
+			sa6 = (struct sockaddr_in6 *)(fwd_tag + 1);
+			bcopy(args.next_hop6, sa6, len);
+			/*
+			 * If nh6 address is link-local we should convert
+			 * it to kernel internal form before doing any
+			 * comparisons.
+			 */
+			if (sa6_embedscope(sa6, V_ip6_use_defzone) != 0) {
+				ret = EACCES;
+				break;
+			}
+			if (in6_localip(&sa6->sin6_addr))
 				(*m0)->m_flags |= M_FASTFWD_OURS;
 			(*m0)->m_flags |= M_IP6_NEXTHOP;
 		}
@@ -279,8 +299,112 @@ again:
 			FREE_PKT(*m0);
 		*m0 = NULL;
 	}
-	if (*m0 && mtod(*m0, struct ip *)->ip_v == 4)
-		SET_HOST_IPLEN(mtod(*m0, struct ip *));
+
+	return ret;
+}
+
+/*
+ * ipfw processing for ethernet packets (in and out).
+ * Inteface is NULL from ether_demux, and ifp from
+ * ether_output_frame.
+ */
+int
+ipfw_check_frame(void *arg, struct mbuf **m0, struct ifnet *dst, int dir,
+    struct inpcb *inp)
+{
+	struct ether_header *eh;
+	struct ether_header save_eh;
+	struct mbuf *m;
+	int i, ret;
+	struct ip_fw_args args;
+	struct m_tag *mtag;
+
+	/* fetch start point from rule, if any */
+	mtag = m_tag_locate(*m0, MTAG_IPFW_RULE, 0, NULL);
+	if (mtag == NULL) {
+		args.rule.slot = 0;
+	} else {
+		/* dummynet packet, already partially processed */
+		struct ipfw_rule_ref *r;
+
+		/* XXX can we free it after use ? */
+		mtag->m_tag_id = PACKET_TAG_NONE;
+		r = (struct ipfw_rule_ref *)(mtag + 1);
+		if (r->info & IPFW_ONEPASS)
+			return (0);
+		args.rule = *r;
+	}
+
+	/* I need some amt of data to be contiguous */
+	m = *m0;
+	i = min(m->m_pkthdr.len, max_protohdr);
+	if (m->m_len < i) {
+		m = m_pullup(m, i);
+		if (m == NULL) {
+			*m0 = m;
+			return (0);
+		}
+	}
+	eh = mtod(m, struct ether_header *);
+	save_eh = *eh;			/* save copy for restore below */
+	m_adj(m, ETHER_HDR_LEN);	/* strip ethernet header */
+
+	args.m = m;		/* the packet we are looking at		*/
+	args.oif = dir == PFIL_OUT ? dst: NULL;	/* destination, if any	*/
+	args.next_hop = NULL;	/* we do not support forward yet	*/
+	args.next_hop6 = NULL;	/* we do not support forward yet	*/
+	args.eh = &save_eh;	/* MAC header for bridged/MAC packets	*/
+	args.inp = NULL;	/* used by ipfw uid/gid/jail rules	*/
+	i = ipfw_chk(&args);
+	m = args.m;
+	if (m != NULL) {
+		/*
+		 * Restore Ethernet header, as needed, in case the
+		 * mbuf chain was replaced by ipfw.
+		 */
+		M_PREPEND(m, ETHER_HDR_LEN, M_NOWAIT);
+		if (m == NULL) {
+			*m0 = NULL;
+			return (0);
+		}
+		if (eh != mtod(m, struct ether_header *))
+			bcopy(&save_eh, mtod(m, struct ether_header *),
+				ETHER_HDR_LEN);
+	}
+	*m0 = m;
+
+	ret = 0;
+	/* Check result of ipfw_chk() */
+	switch (i) {
+	case IP_FW_PASS:
+		break;
+
+	case IP_FW_DENY:
+		ret = EACCES;
+		break; /* i.e. drop */
+
+	case IP_FW_DUMMYNET:
+		ret = EACCES;
+		int dir;
+
+		if (ip_dn_io_ptr == NULL)
+			break; /* i.e. drop */
+
+		*m0 = NULL;
+		dir = PROTO_LAYER2 | (dst ? DIR_OUT : DIR_IN);
+		ip_dn_io_ptr(&m, dir, &args);
+		return 0;
+
+	default:
+		KASSERT(0, ("%s: unknown retval", __func__));
+	}
+
+	if (ret != 0) {
+		if (*m0)
+			FREE_PKT(*m0);
+		*m0 = NULL;
+	}
+
 	return ret;
 }
 
@@ -303,7 +427,7 @@ ipfw_divert(struct mbuf **m0, int incoming, struct ipfw_rule_ref *rule,
 		clone = *m0;	/* use the original mbuf */
 		*m0 = NULL;
 	} else {
-		clone = m_dup(*m0, M_DONTWAIT);
+		clone = m_dup(*m0, M_NOWAIT);
 		/* If we cannot duplicate the mbuf, we sacrifice the divert
 		 * chain and continue with the tee-ed packet.
 		 */
@@ -325,7 +449,6 @@ ipfw_divert(struct mbuf **m0, int incoming, struct ipfw_rule_ref *rule,
 		int hlen;
 		struct mbuf *reass;
 
-		SET_HOST_IPLEN(ip); /* ip_reass wants host order */
 		reass = ip_reass(clone); /* Reassemble packet. */
 		if (reass == NULL)
 			return 0; /* not an error */
@@ -336,7 +459,6 @@ ipfw_divert(struct mbuf **m0, int incoming, struct ipfw_rule_ref *rule,
 		 */
 		ip = mtod(reass, struct ip *);
 		hlen = ip->ip_hl << 2;
-		SET_NET_IPLEN(ip);
 		ip->ip_sum = 0;
 		if (hlen == sizeof(struct ip))
 			ip->ip_sum = in_cksum_hdr(ip);
@@ -385,13 +507,16 @@ static int
 ipfw_hook(int onoff, int pf)
 {
 	struct pfil_head *pfh;
+	pfil_func_t hook_func;
 
 	pfh = pfil_head_get(PFIL_TYPE_AF, pf);
 	if (pfh == NULL)
 		return ENOENT;
 
+	hook_func = (pf == AF_LINK) ? ipfw_check_frame : ipfw_check_packet;
+
 	(void) (onoff ? pfil_add_hook : pfil_remove_hook)
-	    (ipfw_check_hook, NULL, PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh);
+	    (hook_func, NULL, PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh);
 
 	return 0;
 }
@@ -415,51 +540,50 @@ ipfw_attach_hooks(int arg)
                 printf("ipfw6_hook() error\n");
         }
 #endif
+	if (arg == 0) /* detach */
+		ipfw_hook(0, AF_LINK);
+	else if (V_fwlink_enable && ipfw_hook(1, AF_LINK) != 0) {
+                error = ENOENT;
+                printf("ipfw_link_hook() error\n");
+        }
 	return error;
 }
 
 int
 ipfw_chg_hook(SYSCTL_HANDLER_ARGS)
 {
-	int enable;
-	int oldenable;
+	int newval;
 	int error;
 	int af;
 
-	if (arg1 == &VNET_NAME(fw_enable)) {
-		enable = V_fw_enable;
+	if (arg1 == &V_fw_enable)
 		af = AF_INET;
-	}
 #ifdef INET6
-	else if (arg1 == &VNET_NAME(fw6_enable)) {
-		enable = V_fw6_enable;
+	else if (arg1 == &V_fw6_enable)
 		af = AF_INET6;
-	}
 #endif
+	else if (arg1 == &V_fwlink_enable)
+		af = AF_LINK;
 	else 
 		return (EINVAL);
 
-	oldenable = enable;
-
-	error = sysctl_handle_int(oidp, &enable, 0, req);
+	newval = *(int *)arg1;
+	/* Handle sysctl change */
+	error = sysctl_handle_int(oidp, &newval, 0, req);
 
 	if (error)
 		return (error);
 
-	enable = (enable) ? 1 : 0;
+	/* Formalize new value */
+	newval = (newval) ? 1 : 0;
 
-	if (enable == oldenable)
+	if (*(int *)arg1 == newval)
 		return (0);
 
-	error = ipfw_hook(enable, af);
+	error = ipfw_hook(newval, af);
 	if (error)
 		return (error);
-	if (af == AF_INET)
-		V_fw_enable = enable;
-#ifdef INET6
-	else if (af == AF_INET6)
-		V_fw6_enable = enable;
-#endif
+	*(int *)arg1 = newval;
 
 	return (0);
 }