Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 279 insertions, 0 deletions

diff --git a/net/ipv4/netfilter/ip_conntrack_proto_icmp.c b/net/ipv4/netfilter/ip_conntrack_proto_icmp.c
new file mode 100644
index 00000000000..602c74db325
--- /dev/null
+++ b/net/ipv4/netfilter/ip_conntrack_proto_icmp.c
@@ -0,0 +1,279 @@
+/* (C) 1999-2001 Paul `Rusty' Russell
+ * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/netfilter.h>
+#include <linux/in.h>
+#include <linux/icmp.h>
+#include <linux/seq_file.h>
+#include <net/ip.h>
+#include <net/checksum.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/netfilter_ipv4/ip_conntrack.h>
+#include <linux/netfilter_ipv4/ip_conntrack_core.h>
+#include <linux/netfilter_ipv4/ip_conntrack_protocol.h>
+
+unsigned long ip_ct_icmp_timeout = 30*HZ;
+
+#if 0
+#define DEBUGP printk
+#else
+#define DEBUGP(format, args...)
+#endif
+
+static int icmp_pkt_to_tuple(const struct sk_buff *skb,
+			     unsigned int dataoff,
+			     struct ip_conntrack_tuple *tuple)
+{
+	struct icmphdr _hdr, *hp;
+
+	hp = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
+	if (hp == NULL)
+		return 0;
+
+	tuple->dst.u.icmp.type = hp->type;
+	tuple->src.u.icmp.id = hp->un.echo.id;
+	tuple->dst.u.icmp.code = hp->code;
+
+	return 1;
+}
+
+static int icmp_invert_tuple(struct ip_conntrack_tuple *tuple,
+			     const struct ip_conntrack_tuple *orig)
+{
+	/* Add 1; spaces filled with 0. */
+	static u_int8_t invmap[]
+		= { [ICMP_ECHO] = ICMP_ECHOREPLY + 1,
+		    [ICMP_ECHOREPLY] = ICMP_ECHO + 1,
+		    [ICMP_TIMESTAMP] = ICMP_TIMESTAMPREPLY + 1,
+		    [ICMP_TIMESTAMPREPLY] = ICMP_TIMESTAMP + 1,
+		    [ICMP_INFO_REQUEST] = ICMP_INFO_REPLY + 1,
+		    [ICMP_INFO_REPLY] = ICMP_INFO_REQUEST + 1,
+		    [ICMP_ADDRESS] = ICMP_ADDRESSREPLY + 1,
+		    [ICMP_ADDRESSREPLY] = ICMP_ADDRESS + 1};
+
+	if (orig->dst.u.icmp.type >= sizeof(invmap)
+	    || !invmap[orig->dst.u.icmp.type])
+		return 0;
+
+	tuple->src.u.icmp.id = orig->src.u.icmp.id;
+	tuple->dst.u.icmp.type = invmap[orig->dst.u.icmp.type] - 1;
+	tuple->dst.u.icmp.code = orig->dst.u.icmp.code;
+	return 1;
+}
+
+/* Print out the per-protocol part of the tuple. */
+static int icmp_print_tuple(struct seq_file *s,
+			    const struct ip_conntrack_tuple *tuple)
+{
+	return seq_printf(s, "type=%u code=%u id=%u ",
+			  tuple->dst.u.icmp.type,
+			  tuple->dst.u.icmp.code,
+			  ntohs(tuple->src.u.icmp.id));
+}
+
+/* Print out the private part of the conntrack. */
+static int icmp_print_conntrack(struct seq_file *s,
+				const struct ip_conntrack *conntrack)
+{
+	return 0;
+}
+
+/* Returns verdict for packet, or -1 for invalid. */
+static int icmp_packet(struct ip_conntrack *ct,
+		       const struct sk_buff *skb,
+		       enum ip_conntrack_info ctinfo)
+{
+	/* Try to delete connection immediately after all replies:
+           won't actually vanish as we still have skb, and del_timer
+           means this will only run once even if count hits zero twice
+           (theoretically possible with SMP) */
+	if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) {
+		if (atomic_dec_and_test(&ct->proto.icmp.count)
+		    && del_timer(&ct->timeout))
+			ct->timeout.function((unsigned long)ct);
+	} else {
+		atomic_inc(&ct->proto.icmp.count);
+		ip_ct_refresh_acct(ct, ctinfo, skb, ip_ct_icmp_timeout);
+	}
+
+	return NF_ACCEPT;
+}
+
+/* Called when a new connection for this protocol found. */
+static int icmp_new(struct ip_conntrack *conntrack,
+		    const struct sk_buff *skb)
+{
+	static u_int8_t valid_new[]
+		= { [ICMP_ECHO] = 1,
+		    [ICMP_TIMESTAMP] = 1,
+		    [ICMP_INFO_REQUEST] = 1,
+		    [ICMP_ADDRESS] = 1 };
+
+	if (conntrack->tuplehash[0].tuple.dst.u.icmp.type >= sizeof(valid_new)
+	    || !valid_new[conntrack->tuplehash[0].tuple.dst.u.icmp.type]) {
+		/* Can't create a new ICMP `conn' with this. */
+		DEBUGP("icmp: can't create new conn with type %u\n",
+		       conntrack->tuplehash[0].tuple.dst.u.icmp.type);
+		DUMP_TUPLE(&conntrack->tuplehash[0].tuple);
+		return 0;
+	}
+	atomic_set(&conntrack->proto.icmp.count, 0);
+	return 1;
+}
+
+static int
+icmp_error_message(struct sk_buff *skb,
+		   enum ip_conntrack_info *ctinfo,
+		   unsigned int hooknum)
+{
+	struct ip_conntrack_tuple innertuple, origtuple;
+	struct {
+		struct icmphdr icmp;
+		struct iphdr ip;
+	} _in, *inside;
+	struct ip_conntrack_protocol *innerproto;
+	struct ip_conntrack_tuple_hash *h;
+	int dataoff;
+
+	IP_NF_ASSERT(skb->nfct == NULL);
+
+	/* Not enough header? */
+	inside = skb_header_pointer(skb, skb->nh.iph->ihl*4, sizeof(_in), &_in);
+	if (inside == NULL)
+		return NF_ACCEPT;
+
+	/* Ignore ICMP's containing fragments (shouldn't happen) */
+	if (inside->ip.frag_off & htons(IP_OFFSET)) {
+		DEBUGP("icmp_error_track: fragment of proto %u\n",
+		       inside->ip.protocol);
+		return NF_ACCEPT;
+	}
+
+	innerproto = ip_ct_find_proto(inside->ip.protocol);
+	dataoff = skb->nh.iph->ihl*4 + sizeof(inside->icmp) + inside->ip.ihl*4;
+	/* Are they talking about one of our connections? */
+	if (!ip_ct_get_tuple(&inside->ip, skb, dataoff, &origtuple, innerproto)) {
+		DEBUGP("icmp_error: ! get_tuple p=%u", inside->ip.protocol);
+		return NF_ACCEPT;
+	}
+
+	/* Ordinarily, we'd expect the inverted tupleproto, but it's
+	   been preserved inside the ICMP. */
+	if (!ip_ct_invert_tuple(&innertuple, &origtuple, innerproto)) {
+		DEBUGP("icmp_error_track: Can't invert tuple\n");
+		return NF_ACCEPT;
+	}
+
+	*ctinfo = IP_CT_RELATED;
+
+	h = ip_conntrack_find_get(&innertuple, NULL);
+	if (!h) {
+		/* Locally generated ICMPs will match inverted if they
+		   haven't been SNAT'ed yet */
+		/* FIXME: NAT code has to handle half-done double NAT --RR */
+		if (hooknum == NF_IP_LOCAL_OUT)
+			h = ip_conntrack_find_get(&origtuple, NULL);
+
+		if (!h) {
+			DEBUGP("icmp_error_track: no match\n");
+			return NF_ACCEPT;
+		}
+		/* Reverse direction from that found */
+		if (DIRECTION(h) != IP_CT_DIR_REPLY)
+			*ctinfo += IP_CT_IS_REPLY;
+	} else {
+		if (DIRECTION(h) == IP_CT_DIR_REPLY)
+			*ctinfo += IP_CT_IS_REPLY;
+	}
+
+	/* Update skb to refer to this connection */
+	skb->nfct = &tuplehash_to_ctrack(h)->ct_general;
+	skb->nfctinfo = *ctinfo;
+	return -NF_ACCEPT;
+}
+
+/* Small and modified version of icmp_rcv */
+static int
+icmp_error(struct sk_buff *skb, enum ip_conntrack_info *ctinfo,
+	   unsigned int hooknum)
+{
+	struct icmphdr _ih, *icmph;
+
+	/* Not enough header? */
+	icmph = skb_header_pointer(skb, skb->nh.iph->ihl*4, sizeof(_ih), &_ih);
+	if (icmph == NULL) {
+		if (LOG_INVALID(IPPROTO_ICMP))
+			nf_log_packet(PF_INET, 0, skb, NULL, NULL,
+				      "ip_ct_icmp: short packet ");
+		return -NF_ACCEPT;
+	}
+
+	/* See ip_conntrack_proto_tcp.c */
+	if (hooknum != NF_IP_PRE_ROUTING)
+		goto checksum_skipped;
+
+	switch (skb->ip_summed) {
+	case CHECKSUM_HW:
+		if (!(u16)csum_fold(skb->csum)) 
+			break;
+		if (LOG_INVALID(IPPROTO_ICMP))
+			nf_log_packet(PF_INET, 0, skb, NULL, NULL, 
+				      "ip_ct_icmp: bad HW ICMP checksum ");
+		return -NF_ACCEPT;
+	case CHECKSUM_NONE:
+		if ((u16)csum_fold(skb_checksum(skb, 0, skb->len, 0))) {
+			if (LOG_INVALID(IPPROTO_ICMP))
+				nf_log_packet(PF_INET, 0, skb, NULL, NULL, 
+					      "ip_ct_icmp: bad ICMP checksum ");
+			return -NF_ACCEPT;
+		}
+	default:
+		break;
+	}
+
+checksum_skipped:
+	/*
+	 *	18 is the highest 'known' ICMP type. Anything else is a mystery
+	 *
+	 *	RFC 1122: 3.2.2  Unknown ICMP messages types MUST be silently
+	 *		  discarded.
+	 */
+	if (icmph->type > NR_ICMP_TYPES) {
+		if (LOG_INVALID(IPPROTO_ICMP))
+			nf_log_packet(PF_INET, 0, skb, NULL, NULL,
+				      "ip_ct_icmp: invalid ICMP type ");
+		return -NF_ACCEPT;
+	}
+
+	/* Need to track icmp error message? */
+	if (icmph->type != ICMP_DEST_UNREACH
+	    && icmph->type != ICMP_SOURCE_QUENCH
+	    && icmph->type != ICMP_TIME_EXCEEDED
+	    && icmph->type != ICMP_PARAMETERPROB
+	    && icmph->type != ICMP_REDIRECT)
+		return NF_ACCEPT;
+
+	return icmp_error_message(skb, ctinfo, hooknum);
+}
+
+struct ip_conntrack_protocol ip_conntrack_protocol_icmp =
+{
+	.proto 			= IPPROTO_ICMP,
+	.name 			= "icmp",
+	.pkt_to_tuple		= icmp_pkt_to_tuple,
+	.invert_tuple		= icmp_invert_tuple,
+	.print_tuple		= icmp_print_tuple,
+	.print_conntrack	= icmp_print_conntrack,
+	.packet			= icmp_packet,
+	.new			= icmp_new,
+	.error			= icmp_error,
+};