remove tarpit patches (#4432)

SVN-Revision: 14418

target/linux/generic-2.6/patches-2.6.28/171-netfilter_tarpit.patch

@@ -1,318 +0,0 @@
---- a/net/netfilter/Kconfig
-+++ b/net/netfilter/Kconfig
-@@ -469,6 +469,23 @@ config NETFILTER_XT_TARGET_SECMARK
- 
- 	  To compile it as a module, choose M here.  If unsure, say N.
- 
-+config NETFILTER_XT_TARGET_TARPIT
-+	tristate '"TARPIT" target support'
-+	depends on NETFILTER_XTABLES
-+	---help---
-+	  Adds a TARPIT target to iptables, which captures and holds
-+	  incoming TCP connections using no local per-connection resources.
-+	  Connections are accepted, but immediately switched to the persist
-+	  state (0 byte window), in which the remote side stops sending data
-+	  and asks to continue every 60-240 seconds. Attempts to close the
-+	  connection are ignored, forcing the remote side to time out the
-+	  connection in 12-24 minutes.
-+
-+	  This offers similar functionality to LaBrea
-+	  <http://www.hackbusters.net/LaBrea/>, but does not require dedicated
-+	  hardware or IPs. Any TCP port that you would normally DROP or REJECT
-+	  can instead become a tarpit.
-+
- config NETFILTER_XT_TARGET_TCPMSS
- 	tristate '"TCPMSS" target support'
- 	depends on (IPV6 || IPV6=n)
---- a/net/netfilter/Makefile
-+++ b/net/netfilter/Makefile
-@@ -51,6 +51,7 @@ obj-$(CONFIG_NETFILTER_XT_TARGET_NFQUEUE
- obj-$(CONFIG_NETFILTER_XT_TARGET_NOTRACK) += xt_NOTRACK.o
- obj-$(CONFIG_NETFILTER_XT_TARGET_RATEEST) += xt_RATEEST.o
- obj-$(CONFIG_NETFILTER_XT_TARGET_SECMARK) += xt_SECMARK.o
-+obj-$(CONFIG_NETFILTER_XT_TARGET_TARPIT) += xt_TARPIT.o
- obj-$(CONFIG_NETFILTER_XT_TARGET_TPROXY) += xt_TPROXY.o
- obj-$(CONFIG_NETFILTER_XT_TARGET_TCPMSS) += xt_TCPMSS.o
- obj-$(CONFIG_NETFILTER_XT_TARGET_TCPOPTSTRIP) += xt_TCPOPTSTRIP.o
---- /dev/null
-+++ b/net/netfilter/xt_TARPIT.c
-@@ -0,0 +1,279 @@
-+/*
-+ * Kernel module to capture and hold incoming TCP connections using
-+ * no local per-connection resources.
-+ *
-+ * Based on ipt_REJECT.c and offering functionality similar to
-+ * LaBrea <http://www.hackbusters.net/LaBrea/>.
-+ *
-+ * Copyright (c) 2002 Aaron Hopkins <[email protected]>
-+ *
-+ * This program is free software; you can redistribute it and/or modify
-+ * it under the terms of the GNU General Public License as published by
-+ * the Free Software Foundation; either version 2 of the License, or
-+ * (at your option) any later version.
-+ *
-+ * This program is distributed in the hope that it will be useful,
-+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
-+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-+ * GNU General Public License for more details.
-+ *
-+ * You should have received a copy of the GNU General Public License
-+ * along with this program; if not, write to the Free Software
-+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-+ *
-+ * Goal:
-+ * - Allow incoming TCP connections to be established.
-+ * - Passing data should result in the connection being switched to the
-+ *   persist state (0 byte window), in which the remote side stops sending
-+ *   data and asks to continue every 60 seconds.
-+ * - Attempts to shut down the connection should be ignored completely, so
-+ *   the remote side ends up having to time it out.
-+ *
-+ * This means:
-+ * - Reply to TCP SYN,!ACK,!RST,!FIN with SYN-ACK, window 5 bytes
-+ * - Reply to TCP SYN,ACK,!RST,!FIN with RST to prevent spoofing
-+ * - Reply to TCP !SYN,!RST,!FIN with ACK, window 0 bytes, rate-limited
-+ */
-+
-+#include <linux/version.h>
-+#include <linux/module.h>
-+#include <linux/skbuff.h>
-+#include <linux/ip.h>
-+#include <net/ip.h>
-+#include <net/tcp.h>
-+#include <net/icmp.h>
-+struct in_device;
-+#include <net/route.h>
-+#include <linux/random.h>
-+#include <linux/netfilter_ipv4/ip_tables.h>
-+
-+#if 0
-+#define DEBUGP printk
-+#else
-+#define DEBUGP(format, args...)
-+#endif
-+
-+/* Stolen from ip_finish_output2 */
-+static int ip_direct_send(struct sk_buff *skb)
-+{
-+	struct dst_entry *dst = skb->dst;
-+
-+        if (dst->hh != NULL)
-+		return neigh_hh_output(dst->hh, skb);
-+	else if (dst->neighbour != NULL)
-+		return dst->neighbour->output(skb);
-+
-+	if (net_ratelimit())
-+		printk(KERN_DEBUG "TARPIT ip_direct_send: no header cache and no neighbor!\n");
-+
-+	kfree_skb(skb);
-+	return -EINVAL;
-+}
-+
-+
-+/* Send reply */
-+static void tarpit_tcp(const struct sk_buff *oskb, struct rtable *ort,
-+                       unsigned int local)
-+{
-+	struct sk_buff *nskb;
-+	struct rtable *nrt;
-+	struct tcphdr *otcph, *ntcph;
-+	struct flowi fl = {};
-+	unsigned int otcplen;
-+	u_int16_t tmp;
-+
-+	const struct iphdr *oiph = ip_hdr(oskb);
-+	struct iphdr *niph;
-+
-+	/* A truncated TCP header is not going to be useful */
-+	if (oskb->len < ip_hdrlen(oskb) + sizeof(struct tcphdr))
-+		return;
-+
-+	otcph   = (void *)oiph + ip_hdrlen(oskb);
-+	otcplen = oskb->len - ip_hdrlen(oskb);
-+
-+	/* No replies for RST or FIN */
-+	if (otcph->rst || otcph->fin)
-+		return;
-+
-+	/* No reply to !SYN,!ACK.  Rate-limit replies to !SYN,ACKs */
-+	if (!otcph->syn && (!otcph->ack || !xrlim_allow(&ort->u.dst, 1*HZ)))
-+		return;
-+
-+	/* Check checksum. */
-+	if (tcp_v4_check(otcplen, oiph->saddr, oiph->daddr,
-+	    csum_partial((char *)otcph, otcplen, 0)) != 0)
-+		return;
-+
-+	/*
-+	 * Copy skb (even if skb is about to be dropped, we cannot just
-+	 * clone it because there may be other things, such as tcpdump,
-+	 * interested in it)
-+	 */
-+	nskb = skb_copy(oskb, GFP_ATOMIC);
-+	if (nskb == NULL)
-+		return;
-+
-+	niph = ip_hdr(nskb);
-+
-+	/* This packet will not be the same as the other: clear nf fields */
-+	nf_conntrack_put(nskb->nfct);
-+	nskb->nfct = NULL;
-+#ifdef CONFIG_NETFILTER_DEBUG
-+	nskb->nf_debug = 0;
-+#endif
-+
-+	ntcph = (void *)niph + ip_hdrlen(nskb);
-+
-+	/* Truncate to length (no data) */
-+	ntcph->doff = sizeof(struct tcphdr)/4;
-+	skb_trim(nskb, ip_hdrlen(nskb) + sizeof(struct tcphdr));
-+	niph->tot_len = htons(nskb->len);
-+
-+	/* Swap source and dest */
-+	niph->daddr = xchg(&niph->saddr, niph->daddr);
-+	tmp = ntcph->source;
-+	ntcph->source = ntcph->dest;
-+	ntcph->dest = tmp;
-+
-+	/* Use supplied sequence number or make a new one */
-+	ntcph->seq = otcph->ack ? otcph->ack_seq
-+		: htonl(secure_tcp_sequence_number(niph->saddr,
-+						   niph->daddr,
-+						   ntcph->source,
-+						   ntcph->dest));
-+
-+	/* Our SYN-ACKs must have a >0 window */
-+	ntcph->window = (otcph->syn && !otcph->ack) ? htons(5) : 0;
-+
-+	ntcph->urg_ptr = 0;
-+
-+	/* Reset flags */
-+	((u_int8_t *)ntcph)[13] = 0;
-+
-+	if (otcph->syn && otcph->ack) {
-+		ntcph->rst = 1;
-+		ntcph->ack_seq = 0;
-+	} else {
-+		ntcph->syn = otcph->syn;
-+		ntcph->ack = 1;
-+		ntcph->ack_seq = htonl(ntohl(otcph->seq) + otcph->syn);
-+	}
-+
-+	/* Adjust TCP checksum */
-+	ntcph->check = 0;
-+	ntcph->check = tcp_v4_check(sizeof(struct tcphdr),
-+				   niph->saddr,
-+				   niph->daddr,
-+				   csum_partial((char *)ntcph,
-+						sizeof(struct tcphdr), 0));
-+
-+	fl.nl_u.ip4_u.daddr = niph->daddr;
-+	fl.nl_u.ip4_u.saddr = local ? niph->saddr : 0;
-+	fl.nl_u.ip4_u.tos = RT_TOS(niph->tos) | RTO_CONN;
-+	fl.oif = 0;
-+
-+	if (ip_route_output_key(&init_net, &nrt, &fl))
-+		goto free_nskb;
-+
-+	dst_release(nskb->dst);
-+	nskb->dst = &nrt->u.dst;
-+
-+	/* Adjust IP TTL */
-+	niph->ttl = dst_metric(nskb->dst, RTAX_HOPLIMIT);
-+
-+	/* Set DF, id = 0 */
-+	niph->frag_off = htons(IP_DF);
-+	niph->id = 0;
-+
-+	/* Adjust IP checksum */
-+	niph->check = 0;
-+	niph->check = ip_fast_csum((unsigned char *)niph, niph->ihl);
-+
-+	/* "Never happens" */
-+	if (nskb->len > dst_mtu(nskb->dst))
-+		goto free_nskb;
-+
-+	ip_direct_send(nskb);
-+	return;
-+
-+ free_nskb:
-+	kfree_skb(nskb);
-+}
-+
-+static unsigned int xt_tarpit_target(struct sk_buff *skb,
-+                                     const struct net_device *in,
-+                                     const struct net_device *out,
-+                                     unsigned int hooknum,
-+                                     const struct xt_target *target,
-+                                     const void *targinfo)
-+{
-+	const struct iphdr *iph   = ip_hdr(skb);
-+	struct rtable *rt         = (void *)skb->dst;
-+
-+	/* Do we have an input route cache entry? */
-+	if (rt == NULL)
-+		return NF_DROP;
-+
-+	/* No replies to physical multicast/broadcast */
-+	if (skb->pkt_type != PACKET_HOST && skb->pkt_type != PACKET_OTHERHOST)
-+		return NF_DROP;
-+
-+	/* Now check at the protocol level */
-+	if (rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST))
-+		return NF_DROP;
-+
-+	/*
-+	 * Our naive response construction does not deal with IP
-+	 * options, and probably should not try.
-+	 */
-+	if (iph->ihl * 4 != sizeof(struct iphdr))
-+		return NF_DROP;
-+
-+	/* We are not interested in fragments */
-+	if (iph->frag_off & htons(IP_OFFSET))
-+		return NF_DROP;
-+
-+	tarpit_tcp(skb, rt, hooknum == NF_INET_LOCAL_IN);
-+	return NF_DROP;
-+}
-+
-+static bool xt_tarpit_check(const char *tablename, const void *entry,
-+                            const struct xt_target *target, void *targinfo,
-+                            unsigned int hook_mask)
-+{
-+	bool invalid;
-+
-+	if (strcmp(tablename, "raw") == 0 && hook_mask == NF_INET_PRE_ROUTING)
-+		return true;
-+	if (strcmp(tablename, "filter") != 0)
-+		return false;
-+	invalid = hook_mask & ~((1 << NF_INET_LOCAL_IN) | (1 << NF_INET_FORWARD));
-+	return !invalid;
-+}
-+
-+static struct xt_target xt_tarpit_reg = {
-+	.name       = "TARPIT",
-+	.family     = AF_INET,
-+	.proto      = IPPROTO_TCP,
-+	.target     = xt_tarpit_target,
-+	.checkentry = xt_tarpit_check,
-+	.me         = THIS_MODULE,
-+};
-+
-+static int __init xt_tarpit_init(void)
-+{
-+	return xt_register_target(&xt_tarpit_reg);
-+}
-+
-+static void __exit xt_tarpit_exit(void)
-+{
-+	xt_unregister_target(&xt_tarpit_reg);
-+}
-+
-+module_init(xt_tarpit_init);
-+module_exit(xt_tarpit_exit);
-+MODULE_DESCRIPTION("netfilter xt_TARPIT target module");
-+MODULE_AUTHOR("Jan Engelhardt <[email protected]>");
-+MODULE_LICENSE("GPL");
-+MODULE_ALIAS("ipt_TARPIT");