diff --git a/extensions/Kbuild b/extensions/Kbuild
index 2717b31..25fa72f 100644
--- a/extensions/Kbuild
+++ b/extensions/Kbuild
@@ -19,6 +19,7 @@ obj-${build_fuzzy}       += xt_fuzzy.o
 obj-${build_geoip}       += xt_geoip.o
 obj-${build_ipp2p}       += xt_ipp2p.o
 obj-${build_ipset}       += ipset/
+obj-${build_length2}     += xt_length2.o
 obj-${build_portscan}    += xt_portscan.o
 obj-${build_quota2}      += xt_quota2.o
 
diff --git a/extensions/Mbuild b/extensions/Mbuild
index 6fbda26..05f6485 100644
--- a/extensions/Mbuild
+++ b/extensions/Mbuild
@@ -12,5 +12,6 @@ obj-${build_fuzzy}       += libxt_fuzzy.so
 obj-${build_geoip}       += libxt_geoip.so
 obj-${build_ipp2p}       += libxt_ipp2p.so
 obj-${build_ipset}       += ipset/
+obj-${build_length2}     += libxt_length2.so
 obj-${build_portscan}    += libxt_portscan.so
 obj-${build_quota2}      += libxt_quota2.so
diff --git a/extensions/libxt_length.man b/extensions/libxt_length.man
new file mode 100644
index 0000000..235504e
--- /dev/null
+++ b/extensions/libxt_length.man
@@ -0,0 +1,18 @@
+This module matches the length of a packet against a specific value or range of
+values.
+.TP
+[\fB!\fR] \fB--length\fR \fIlength\fR[\fB:\fR\fIlength\fR]
+Match exact length or length range.
+.TP
+\fB--layer3\fR
+Match the layer3 frame size (e.g. IPv4/v6 header plus payload).
+.TP
+\fB--layer4\fR
+Match the layer4 frame size (e.g. TCP/UDP header plus payload).
+.TP
+\fB--layer5\fR
+Match the layer5 frame size (e.g. TCP/UDP payload, often called layer7).
+.PP
+If no --layer* option is given, --layer3 is assumed by default. Note that using
+--layer5 may not match a packet if it is not one of the recognized types
+(currently TCP, UDP, UDPLite, ICMP, AH and ESP) or which has no 5th layer.
diff --git a/extensions/libxt_length2.c b/extensions/libxt_length2.c
new file mode 100644
index 0000000..130a321
--- /dev/null
+++ b/extensions/libxt_length2.c
@@ -0,0 +1,173 @@
+#include <getopt.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <xtables.h>
+#include "xt_length2.h"
+
+enum {
+	F_LAYER  = 1 << 0,
+	F_LENGTH = 1 << 1,
+
+	XT_LENGTH_LAYER_MASK = XT_LENGTH_LAYER3 | XT_LENGTH_LAYER4 |
+	                       XT_LENGTH_LAYER5 | XT_LENGTH_LAYER7,
+};
+
+static void length_mt_help(void)
+{
+	printf(
+"length match options:\n"
+"    --layer3          Match against layer3 size (e.g. L4 + IPv6 header)\n"
+"    --layer4          Match against layer4 size (e.g. L5 + SCTP header)\n"
+"    --layer5          Match against layer5 size (e.g. L7 + chunk headers)\n"
+"    --layer7          Match against layer7 payload (e.g. SCTP payload)\n"
+"[!] --length n[:n]    Match packet length against value or range\n"
+"                      of values (inclusive)\n"
+);
+}
+
+static const struct option length_mt_opts[] = {
+	{.name = "layer3", .has_arg = false, .val = '3'},
+	{.name = "layer4", .has_arg = false, .val = '4'},
+	{.name = "layer5", .has_arg = false, .val = '5'},
+	{.name = "layer7", .has_arg = false, .val = '7'},
+	{.name = "length", .has_arg = true,  .val = '='},
+	{NULL},
+};
+
+static void length_mt_init(struct xt_entry_match *match)
+{
+	struct xt_length_mtinfo2 *info = (void *)match->data;
+
+	info->flags = XT_LENGTH_LAYER3;
+}
+
+static int length_mt_parse(int c, char **argv, int invert, unsigned int *flags,
+                           const void *entry, struct xt_entry_match **match)
+{
+	struct xt_length_mtinfo2 *info = (void *)(*match)->data;
+	unsigned int from, to;
+	char *end;
+
+	switch (c) {
+	case '3': /* --layer3 */
+		param_act(P_ONLY_ONCE, "length", "--layer*", *flags & F_LAYER);
+		info->flags &= ~XT_LENGTH_LAYER_MASK;
+		info->flags |= XT_LENGTH_LAYER3;
+		*flags |= F_LAYER;
+		return true;
+	case '4': /* --layer4 */
+		param_act(P_ONLY_ONCE, "length", "--layer*", *flags & F_LAYER);
+		info->flags &= ~XT_LENGTH_LAYER_MASK;
+		info->flags |= XT_LENGTH_LAYER4;
+		*flags |= F_LAYER;
+		return true;
+	case '5': /* --layer5 */
+		param_act(P_ONLY_ONCE, "length", "--layer*", *flags & F_LAYER);
+		info->flags &= ~XT_LENGTH_LAYER_MASK;
+		info->flags |= XT_LENGTH_LAYER5;
+		*flags |= F_LAYER;
+		return true;
+	case '7': /* --layer7 */
+		param_act(P_ONLY_ONCE, "length", "--layer*", *flags & F_LAYER);
+		info->flags &= ~XT_LENGTH_LAYER_MASK;
+		info->flags |= XT_LENGTH_LAYER7;
+		*flags |= F_LAYER;
+		return true;
+	case '=': /* --length */
+		param_act(P_ONLY_ONCE, "length", "--length", *flags & F_LENGTH);
+		if (invert)
+			info->flags |= XT_LENGTH_INVERT;
+		if (!strtonum(optarg, &end, &from, 0, ~0U))
+			param_act(P_BAD_VALUE, "length", "--length", optarg);
+		to = from;
+		if (*end == ':')
+			if (!strtonum(end + 1, &end, &to, 0, ~0U))
+				param_act(P_BAD_VALUE, "length",
+				          "--length", optarg);
+		if (*end != '\0')
+			param_act(P_BAD_VALUE, "length", "--length", optarg);
+		info->min = from;
+		info->max = to;
+		*flags |= F_LENGTH;
+		return true;
+	}
+	return false;
+}
+
+static void length_mt_check(unsigned int flags)
+{
+	if (!(flags & F_LENGTH))
+		exit_error(PARAMETER_PROBLEM,
+		           "length: You must specify \"--length\"");
+	if (!(flags & F_LAYER))
+		fprintf(stderr, "iptables: length match: Defaulting to "
+		        "--layer3. Consider specifying it explicitly.\n");
+}
+
+static void length_mt_print(const void *ip, const struct xt_entry_match *match,
+                            int numeric)
+{
+	const struct xt_length_mtinfo2 *info = (const void *)match->data;
+
+	if (info->flags & XT_LENGTH_LAYER3)
+		printf("layer3 ");
+	else if (info->flags & XT_LENGTH_LAYER4)
+		printf("layer4 ");
+	else if (info->flags & XT_LENGTH_LAYER5)
+		printf("layer5 ");
+	else if (info->flags & XT_LENGTH_LAYER7)
+		printf("layer7 ");
+	printf("length ");
+	if (info->flags & XT_LENGTH_INVERT)
+		printf("! ");
+	if (info->min == info->max)
+		printf("%u ", (unsigned int)info->min);
+	else
+		printf("%u-%u ", (unsigned int)info->min,
+		       (unsigned int)info->max);
+}
+
+static void length_mt_save(const void *ip, const struct xt_entry_match *match)
+{
+	const struct xt_length_mtinfo2 *info = (const void *)match->data;
+
+	if (info->flags & XT_LENGTH_LAYER3)
+		printf("--layer3 ");
+	else if (info->flags & XT_LENGTH_LAYER4)
+		printf("--layer4 ");
+	else if (info->flags & XT_LENGTH_LAYER5)
+		printf("--layer5 ");
+	else if (info->flags & XT_LENGTH_LAYER7)
+		printf("--layer7 ");
+	if (info->flags & XT_LENGTH_INVERT)
+		printf("! ");
+	printf("--length ");
+	if (info->min == info->max)
+		printf("%u ", (unsigned int)info->min);
+	else
+		printf("%u:%u ", (unsigned int)info->min,
+		       (unsigned int)info->max);
+}
+
+static struct xtables_match length2_mt_reg = {
+	.version        = XTABLES_VERSION,
+	.name           = "length2",
+	.revision       = 2,
+	.family         = PF_UNSPEC,
+	.size           = XT_ALIGN(sizeof(struct xt_length_mtinfo2)),
+	.userspacesize  = XT_ALIGN(sizeof(struct xt_length_mtinfo2)),
+	.init           = length_mt_init,
+	.help           = length_mt_help,
+	.parse          = length_mt_parse,
+	.final_check    = length_mt_check,
+	.print          = length_mt_print,
+	.save           = length_mt_save,
+	.extra_opts     = length_mt_opts,
+};
+
+static void _init(void)
+{
+	xtables_register_match(&length2_mt_reg);
+}
diff --git a/extensions/xt_length2.c b/extensions/xt_length2.c
new file mode 100644
index 0000000..a329cbd
--- /dev/null
+++ b/extensions/xt_length2.c
@@ -0,0 +1,262 @@
+/*
+ *	xt_length - Netfilter module to match packet length
+ *	Copyright © Jan Engelhardt <jengelh@medozas.de>, 2007 - 2009
+ *
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License; either
+ *	version 2 of the License, or any later version, as published by the
+ *	Free Software Foundation.
+ */
+#include <linux/dccp.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/icmp.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/sctp.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <net/ip.h>
+#include <net/ipv6.h>
+#include <linux/netfilter/x_tables.h>
+#include <linux/netfilter_ipv6/ip6_tables.h>
+#include "xt_length2.h"
+#include "compat_xtables.h"
+#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
+#	define WITH_IPV6 1
+#endif
+#ifndef NEXTHDR_IPV4
+#	define NEXTHDR_IPV4 4
+#endif
+
+MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>");
+MODULE_DESCRIPTION("Xtables: Packet length (Layer3,4,5) match");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("ipt_length2");
+MODULE_ALIAS("ip6t_length2");
+
+static bool
+xtlength_layer5_tcp(unsigned int *length, const struct sk_buff *skb,
+                    unsigned int offset)
+{
+	const struct tcphdr *tcph;
+	struct tcphdr buf;
+
+	tcph = skb_header_pointer(skb, offset, sizeof(buf), &buf);
+	if (tcph == NULL)
+		return false;
+
+	*length = skb->len - offset;
+	if (*length >= 4 * tcph->doff)
+		*length -= 4 * tcph->doff;
+	return true;
+}
+
+static bool
+xtlength_layer5_dccp(unsigned int *length, const struct sk_buff *skb,
+                     unsigned int offset)
+{
+	const struct dccp_hdr *dh;
+	struct dccp_hdr dhbuf;
+
+	dh = skb_header_pointer(skb, offset, sizeof(dhbuf), &dhbuf);
+	if (dh == NULL)
+		return false;
+
+	*length = skb->len - offset;
+	if (*length >= 4 * dh->dccph_doff)
+		*length -= 4 * dh->dccph_doff;
+	return true;
+}
+
+static inline bool
+xtlength_layer5(unsigned int *length, const struct sk_buff *skb,
+                unsigned int prot, unsigned int offset)
+{
+	switch (prot) {
+	case IPPROTO_TCP:
+		return xtlength_layer5_tcp(length, skb, offset);
+	case IPPROTO_UDP:
+	case IPPROTO_UDPLITE:
+		*length = skb->len - offset - sizeof(struct udphdr);
+		return true;
+	case IPPROTO_SCTP:
+		*length = skb->len - offset - sizeof(struct sctphdr);
+		return true;
+	case IPPROTO_DCCP:
+		return xtlength_layer5_dccp(length, skb, offset);
+	case IPPROTO_ICMP:
+		*length = skb->len - offset - sizeof(struct icmphdr);
+		return true;
+	case IPPROTO_ICMPV6:
+		*length = skb->len - offset -
+		          offsetof(struct icmp6hdr, icmp6_dataun);
+		return true;
+	case IPPROTO_AH:
+		*length = skb->len - offset - sizeof(struct ip_auth_hdr);
+		return true;
+	case IPPROTO_ESP:
+		*length = skb->len - offset - sizeof(struct ip_esp_hdr);
+		return true;
+	}
+	return false;
+}
+
+static bool
+xtlength_layer7_sctp(unsigned int *length, const struct sk_buff *skb,
+                     unsigned int offset)
+{
+	const struct sctp_chunkhdr *ch;
+	struct sctp_chunkhdr chbuf;
+	unsigned int pos;
+
+	*length = 0;
+	for (pos = sizeof(struct sctphdr); pos < skb->len;
+	     pos += ntohs(ch->length))
+	{
+		ch = skb_header_pointer(skb, offset + pos,
+		     sizeof(chbuf), &chbuf);
+		if (ch == NULL)
+			return false;
+		if (ch->type != SCTP_CID_DATA)
+			continue;
+		*length += ntohs(ch->length);
+	}
+	return true;
+}
+
+static bool xtlength_layer7(unsigned int *length, const struct sk_buff *skb,
+                            unsigned int proto, unsigned int offset)
+{
+	switch (proto) {
+	case IPPROTO_SCTP:
+		return xtlength_layer7_sctp(length, skb, offset);
+	default:
+		return xtlength_layer5(length, skb, proto, offset);
+	}
+}
+
+/**
+ * llayer4_proto - figure out the L4 protocol in an IPv6 packet
+ * @skb:	skb pointer
+ * @offset:	position at which L4 starts (equal to 'protoff' in IPv4 code)
+ * @hotdrop:	hotdrop pointer
+ *
+ * Searches for a recognized L4 header. On success, fills in @offset and
+ * returns the protocol number. If not found, %NEXTHDR_MAX is returned.
+ * On error, @hotdrop is set.
+ */
+static unsigned int
+llayer4_proto(const struct sk_buff *skb, unsigned int *offset, bool *hotdrop)
+{
+	/*
+	 * Do encapsulation first so that %NEXTHDR_TCP does not hit the TCP
+	 * part in an IPv6-in-IPv6 encapsulation.
+	 */
+	static const unsigned int types[] =
+		{IPPROTO_IPV6, IPPROTO_IPIP, IPPROTO_ESP, IPPROTO_AH,
+		IPPROTO_ICMP, IPPROTO_TCP, IPPROTO_UDP, IPPROTO_UDPLITE,
+		IPPROTO_SCTP, IPPROTO_DCCP};
+	unsigned int i;
+	int err;
+
+	for (i = 0; i < ARRAY_SIZE(types); ++i) {
+		err = ipv6_find_hdr(skb, offset, types[i], NULL);
+		if (err >= 0)
+			return types[i];
+		if (err != -ENOENT) {
+			*hotdrop = true;
+			break;
+		}
+	}
+
+	return NEXTHDR_MAX;
+}
+
+static bool
+length2_mt(const struct sk_buff *skb, const struct xt_match_param *par)
+{
+	const struct xt_length_mtinfo2 *info = par->matchinfo;
+	const struct iphdr *iph = ip_hdr(skb);
+	unsigned int len = 0;
+	bool hit = true;
+
+	if (info->flags & XT_LENGTH_LAYER3)
+		len = ntohs(iph->tot_len);
+	else if (info->flags & XT_LENGTH_LAYER4)
+		len = ntohs(iph->tot_len) - par->thoff;
+	else if (info->flags & XT_LENGTH_LAYER5)
+		hit = xtlength_layer5(&len, skb, iph->protocol, par->thoff);
+	else if (info->flags & XT_LENGTH_LAYER7)
+		hit = xtlength_layer7(&len, skb, iph->protocol, par->thoff);
+	if (!hit)
+		return false;
+
+	return (len >= info->min && len <= info->max) ^
+	       !!(info->flags & XT_LENGTH_INVERT);
+}
+
+#ifdef WITH_IPV6
+static bool
+length2_mt6(const struct sk_buff *skb, const struct xt_match_param *par)
+{
+	const struct xt_length_mtinfo2 *info = par->matchinfo;
+	const struct ipv6hdr *iph = ipv6_hdr(skb);
+	unsigned int len = 0, l4proto;
+	unsigned int thoff = par->thoff;
+	bool hit = true;
+
+	if (info->flags & XT_LENGTH_LAYER3) {
+		len = sizeof(struct ipv6hdr) + ntohs(iph->payload_len);
+	} else {
+		l4proto = llayer4_proto(skb, &thoff, par->hotdrop);
+		if (l4proto == NEXTHDR_MAX)
+			return false;
+		if (info->flags & XT_LENGTH_LAYER4)
+			len = skb->len - thoff;
+		else if (info->flags & XT_LENGTH_LAYER5)
+			hit = xtlength_layer5(&len, skb, l4proto, thoff);
+		else if (info->flags & XT_LENGTH_LAYER7)
+			hit = xtlength_layer7(&len, skb, l4proto, thoff);
+	}
+	if (!hit)
+		return false;
+
+	return (len >= info->min && len <= info->max) ^
+	       !!(info->flags & XT_LENGTH_INVERT);
+}
+#endif
+
+static struct xt_match length2_mt_reg[] __read_mostly = {
+	{
+		.name           = "length2",
+		.revision       = 2,
+		.family         = NFPROTO_IPV4,
+		.match          = length2_mt,
+		.matchsize      = sizeof(struct xt_length_mtinfo2),
+		.me             = THIS_MODULE,
+	},
+#ifdef WITH_IPV6
+	{
+		.name           = "length2",
+		.revision       = 2,
+		.family         = NFPROTO_IPV6,
+		.match          = length2_mt6,
+		.matchsize      = sizeof(struct xt_length_mtinfo2),
+		.me             = THIS_MODULE,
+	},
+#endif
+};
+
+static int __init length2_mt_init(void)
+{
+	return xt_register_matches(length2_mt_reg, ARRAY_SIZE(length2_mt_reg));
+}
+
+static void __exit length2_mt_exit(void)
+{
+	xt_unregister_matches(length2_mt_reg, ARRAY_SIZE(length2_mt_reg));
+}
+
+module_init(length2_mt_init);
+module_exit(length2_mt_exit);
diff --git a/extensions/xt_length2.h b/extensions/xt_length2.h
new file mode 100644
index 0000000..c708476
--- /dev/null
+++ b/extensions/xt_length2.h
@@ -0,0 +1,22 @@
+#ifndef _LINUX_NETFILTER_XT_LENGTH2_H
+#define _LINUX_NETFILTER_XT_LENGTH2_H
+
+enum {
+	XT_LENGTH_INVERT = 1 << 0,
+
+	/* IP header plus payload */
+	XT_LENGTH_LAYER3 = 1 << 1,
+	/* Strip IP header: */
+	XT_LENGTH_LAYER4 = 1 << 2,
+	/* Strip TCP/UDP/etc. header */
+	XT_LENGTH_LAYER5 = 1 << 3,
+	/* TCP/UDP/SCTP payload */
+	XT_LENGTH_LAYER7 = 1 << 4,
+};
+
+struct xt_length_mtinfo2 {
+	u_int32_t min, max;
+	u_int16_t flags;
+};
+
+#endif /* _LINUX_NETFILTER_XT_LENGTH2_H */
diff --git a/mconfig b/mconfig
index 5fe5828..7dab1a4 100644
--- a/mconfig
+++ b/mconfig
@@ -14,5 +14,6 @@ build_fuzzy=m
 build_geoip=m
 build_ipp2p=m
 build_ipset=m
+build_length2=m
 build_portscan=m
 build_quota2=m