netfilter: ipset; bitmap:port set type support

The module implements the bitmap:port type in two flavours, without
and with timeout support to store TCP/UDP ports from a range.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Patrick McHardy <kaber@trash.net>

net/netfilter/ipset/Kconfig

@@ -41,4 +41,13 @@ config IP_SET_BITMAP_IPMAC
 
 	  To compile it as a module, choose M here.  If unsure, say N.
 
+config IP_SET_BITMAP_PORT
+	tristate "bitmap:port set support"
+	depends on IP_SET
+	help
+	  This option adds the bitmap:port set type support, by which one
+	  can store TCP/UDP port numbers from a range.
+
+	  To compile it as a module, choose M here.  If unsure, say N.
+
 endif # IP_SET

net/netfilter/ipset/Makefile

@@ -10,3 +10,4 @@ obj-$(CONFIG_IP_SET) += ip_set.o
 # bitmap types
 obj-$(CONFIG_IP_SET_BITMAP_IP) += ip_set_bitmap_ip.o
 obj-$(CONFIG_IP_SET_BITMAP_IPMAC) += ip_set_bitmap_ipmac.o
+obj-$(CONFIG_IP_SET_BITMAP_PORT) += ip_set_bitmap_port.o

net/netfilter/ipset/ip_set_bitmap_port.c

+/* Copyright (C) 2003-2011 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
+ *
+ * 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.
+ */
+
+/* Kernel module implementing an IP set type: the bitmap:port type */
+
+#include <linux/module.h>
+#include <linux/ip.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <linux/skbuff.h>
+#include <linux/errno.h>
+#include <linux/uaccess.h>
+#include <linux/bitops.h>
+#include <linux/spinlock.h>
+#include <linux/netlink.h>
+#include <linux/jiffies.h>
+#include <linux/timer.h>
+#include <net/netlink.h>
+
+#include <linux/netfilter/ipset/ip_set.h>
+#include <linux/netfilter/ipset/ip_set_bitmap.h>
+#include <linux/netfilter/ipset/ip_set_getport.h>
+#define IP_SET_BITMAP_TIMEOUT
+#include <linux/netfilter/ipset/ip_set_timeout.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
+MODULE_DESCRIPTION("bitmap:port type of IP sets");
+MODULE_ALIAS("ip_set_bitmap:port");
+
+/* Type structure */
+struct bitmap_port {
+	void *members;		/* the set members */
+	u16 first_port;		/* host byte order, included in range */
+	u16 last_port;		/* host byte order, included in range */
+	size_t memsize;		/* members size */
+	u32 timeout;		/* timeout parameter */
+	struct timer_list gc;	/* garbage collection */
+};
+
+/* Base variant */
+
+static int
+bitmap_port_test(struct ip_set *set, void *value, u32 timeout)
+{
+	const struct bitmap_port *map = set->data;
+	u16 id = *(u16 *)value;
+
+	return !!test_bit(id, map->members);
+}
+
+static int
+bitmap_port_add(struct ip_set *set, void *value, u32 timeout)
+{
+	struct bitmap_port *map = set->data;
+	u16 id = *(u16 *)value;
+
+	if (test_and_set_bit(id, map->members))
+		return -IPSET_ERR_EXIST;
+
+	return 0;
+}
+
+static int
+bitmap_port_del(struct ip_set *set, void *value, u32 timeout)
+{
+	struct bitmap_port *map = set->data;
+	u16 id = *(u16 *)value;
+
+	if (!test_and_clear_bit(id, map->members))
+		return -IPSET_ERR_EXIST;
+
+	return 0;
+}
+
+static int
+bitmap_port_list(const struct ip_set *set,
+		 struct sk_buff *skb, struct netlink_callback *cb)
+{
+	const struct bitmap_port *map = set->data;
+	struct nlattr *atd, *nested;
+	u16 id, first = cb->args[2];
+	u16 last = map->last_port - map->first_port;
+
+	atd = ipset_nest_start(skb, IPSET_ATTR_ADT);
+	if (!atd)
+		return -EMSGSIZE;
+	for (; cb->args[2] <= last; cb->args[2]++) {
+		id = cb->args[2];
+		if (!test_bit(id, map->members))
+			continue;
+		nested = ipset_nest_start(skb, IPSET_ATTR_DATA);
+		if (!nested) {
+			if (id == first) {
+				nla_nest_cancel(skb, atd);
+				return -EMSGSIZE;
+			} else
+				goto nla_put_failure;
+		}
+		NLA_PUT_NET16(skb, IPSET_ATTR_PORT,
+			      htons(map->first_port + id));
+		ipset_nest_end(skb, nested);
+	}
+	ipset_nest_end(skb, atd);
+	/* Set listing finished */
+	cb->args[2] = 0;
+
+	return 0;
+
+nla_put_failure:
+	nla_nest_cancel(skb, nested);
+	ipset_nest_end(skb, atd);
+	if (unlikely(id == first)) {
+		cb->args[2] = 0;
+		return -EMSGSIZE;
+	}
+	return 0;
+}
+
+/* Timeout variant */
+
+static int
+bitmap_port_ttest(struct ip_set *set, void *value, u32 timeout)
+{
+	const struct bitmap_port *map = set->data;
+	const unsigned long *members = map->members;
+	u16 id = *(u16 *)value;
+
+	return ip_set_timeout_test(members[id]);
+}
+
+static int
+bitmap_port_tadd(struct ip_set *set, void *value, u32 timeout)
+{
+	struct bitmap_port *map = set->data;
+	unsigned long *members = map->members;
+	u16 id = *(u16 *)value;
+
+	if (ip_set_timeout_test(members[id]))
+		return -IPSET_ERR_EXIST;
+
+	members[id] = ip_set_timeout_set(timeout);
+
+	return 0;
+}
+
+static int
+bitmap_port_tdel(struct ip_set *set, void *value, u32 timeout)
+{
+	struct bitmap_port *map = set->data;
+	unsigned long *members = map->members;
+	u16 id = *(u16 *)value;
+	int ret = -IPSET_ERR_EXIST;
+
+	if (ip_set_timeout_test(members[id]))
+		ret = 0;
+
+	members[id] = IPSET_ELEM_UNSET;
+	return ret;
+}
+
+static int
+bitmap_port_tlist(const struct ip_set *set,
+		  struct sk_buff *skb, struct netlink_callback *cb)
+{
+	const struct bitmap_port *map = set->data;
+	struct nlattr *adt, *nested;
+	u16 id, first = cb->args[2];
+	u16 last = map->last_port - map->first_port;
+	const unsigned long *members = map->members;
+
+	adt = ipset_nest_start(skb, IPSET_ATTR_ADT);
+	if (!adt)
+		return -EMSGSIZE;
+	for (; cb->args[2] <= last; cb->args[2]++) {
+		id = cb->args[2];
+		if (!ip_set_timeout_test(members[id]))
+			continue;
+		nested = ipset_nest_start(skb, IPSET_ATTR_DATA);
+		if (!nested) {
+			if (id == first) {
+				nla_nest_cancel(skb, adt);
+				return -EMSGSIZE;
+			} else
+				goto nla_put_failure;
+		}
+		NLA_PUT_NET16(skb, IPSET_ATTR_PORT,
+			      htons(map->first_port + id));
+		NLA_PUT_NET32(skb, IPSET_ATTR_TIMEOUT,
+			      htonl(ip_set_timeout_get(members[id])));
+		ipset_nest_end(skb, nested);
+	}
+	ipset_nest_end(skb, adt);
+
+	/* Set listing finished */
+	cb->args[2] = 0;
+
+	return 0;
+
+nla_put_failure:
+	nla_nest_cancel(skb, nested);
+	ipset_nest_end(skb, adt);
+	if (unlikely(id == first)) {
+		cb->args[2] = 0;
+		return -EMSGSIZE;
+	}
+	return 0;
+}
+
+static int
+bitmap_port_kadt(struct ip_set *set, const struct sk_buff *skb,
+		 enum ipset_adt adt, u8 pf, u8 dim, u8 flags)
+{
+	struct bitmap_port *map = set->data;
+	ipset_adtfn adtfn = set->variant->adt[adt];
+	__be16 __port;
+	u16 port = 0;
+
+	if (!ip_set_get_ip_port(skb, pf, flags & IPSET_DIM_ONE_SRC, &__port))
+		return -EINVAL;
+
+	port = ntohs(__port);
+
+	if (port < map->first_port || port > map->last_port)
+		return -IPSET_ERR_BITMAP_RANGE;
+
+	port -= map->first_port;
+
+	return adtfn(set, &port, map->timeout);
+}
+
+static int
+bitmap_port_uadt(struct ip_set *set, struct nlattr *tb[],
+		 enum ipset_adt adt, u32 *lineno, u32 flags)
+{
+	struct bitmap_port *map = set->data;
+	ipset_adtfn adtfn = set->variant->adt[adt];
+	u32 timeout = map->timeout;
+	u32 port;	/* wraparound */
+	u16 id, port_to;
+	int ret = 0;
+
+	if (unlikely(!ip_set_attr_netorder(tb, IPSET_ATTR_PORT) ||
+		     !ip_set_optattr_netorder(tb, IPSET_ATTR_PORT_TO) ||
+		     !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT)))
+		return -IPSET_ERR_PROTOCOL;
+
+	if (tb[IPSET_ATTR_LINENO])
+		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
+
+	port = ip_set_get_h16(tb[IPSET_ATTR_PORT]);
+	if (port < map->first_port || port > map->last_port)
+		return -IPSET_ERR_BITMAP_RANGE;
+
+	if (tb[IPSET_ATTR_TIMEOUT]) {
+		if (!with_timeout(map->timeout))
+			return -IPSET_ERR_TIMEOUT;
+		timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
+	}
+
+	if (adt == IPSET_TEST) {
+		id = port - map->first_port;
+		return adtfn(set, &id, timeout);
+	}
+
+	if (tb[IPSET_ATTR_PORT_TO]) {
+		port_to = ip_set_get_h16(tb[IPSET_ATTR_PORT_TO]);
+		if (port > port_to) {
+			swap(port, port_to);
+			if (port < map->first_port)
+				return -IPSET_ERR_BITMAP_RANGE;
+		}
+	} else
+		port_to = port;
+
+	if (port_to > map->last_port)
+		return -IPSET_ERR_BITMAP_RANGE;
+
+	for (; port <= port_to; port++) {
+		id = port - map->first_port;
+		ret = adtfn(set, &id, timeout);
+
+		if (ret && !ip_set_eexist(ret, flags))
+			return ret;
+		else
+			ret = 0;
+	}
+	return ret;
+}
+
+static void
+bitmap_port_destroy(struct ip_set *set)
+{
+	struct bitmap_port *map = set->data;
+
+	if (with_timeout(map->timeout))
+		del_timer_sync(&map->gc);
+
+	ip_set_free(map->members);
+	kfree(map);
+
+	set->data = NULL;
+}
+
+static void
+bitmap_port_flush(struct ip_set *set)
+{
+	struct bitmap_port *map = set->data;
+
+	memset(map->members, 0, map->memsize);
+}
+
+static int
+bitmap_port_head(struct ip_set *set, struct sk_buff *skb)
+{
+	const struct bitmap_port *map = set->data;
+	struct nlattr *nested;
+
+	nested = ipset_nest_start(skb, IPSET_ATTR_DATA);
+	if (!nested)
+		goto nla_put_failure;
+	NLA_PUT_NET16(skb, IPSET_ATTR_PORT, htons(map->first_port));
+	NLA_PUT_NET16(skb, IPSET_ATTR_PORT_TO, htons(map->last_port));
+	NLA_PUT_NET32(skb, IPSET_ATTR_REFERENCES,
+		      htonl(atomic_read(&set->ref) - 1));
+	NLA_PUT_NET32(skb, IPSET_ATTR_MEMSIZE,
+		      htonl(sizeof(*map) + map->memsize));
+	if (with_timeout(map->timeout))
+		NLA_PUT_NET32(skb, IPSET_ATTR_TIMEOUT, htonl(map->timeout));
+	ipset_nest_end(skb, nested);
+
+	return 0;
+nla_put_failure:
+	return -EMSGSIZE;
+}
+
+static bool
+bitmap_port_same_set(const struct ip_set *a, const struct ip_set *b)
+{
+	const struct bitmap_port *x = a->data;
+	const struct bitmap_port *y = b->data;
+
+	return x->first_port == y->first_port &&
+	       x->last_port == y->last_port &&
+	       x->timeout == y->timeout;
+}
+
+static const struct ip_set_type_variant bitmap_port = {
+	.kadt	= bitmap_port_kadt,
+	.uadt	= bitmap_port_uadt,
+	.adt	= {
+		[IPSET_ADD] = bitmap_port_add,
+		[IPSET_DEL] = bitmap_port_del,
+		[IPSET_TEST] = bitmap_port_test,
+	},
+	.destroy = bitmap_port_destroy,
+	.flush	= bitmap_port_flush,
+	.head	= bitmap_port_head,
+	.list	= bitmap_port_list,
+	.same_set = bitmap_port_same_set,
+};
+
+static const struct ip_set_type_variant bitmap_tport = {
+	.kadt	= bitmap_port_kadt,
+	.uadt	= bitmap_port_uadt,
+	.adt	= {
+		[IPSET_ADD] = bitmap_port_tadd,
+		[IPSET_DEL] = bitmap_port_tdel,
+		[IPSET_TEST] = bitmap_port_ttest,
+	},
+	.destroy = bitmap_port_destroy,
+	.flush	= bitmap_port_flush,
+	.head	= bitmap_port_head,
+	.list	= bitmap_port_tlist,
+	.same_set = bitmap_port_same_set,
+};
+
+static void
+bitmap_port_gc(unsigned long ul_set)
+{
+	struct ip_set *set = (struct ip_set *) ul_set;
+	struct bitmap_port *map = set->data;
+	unsigned long *table = map->members;
+	u32 id;	/* wraparound */
+	u16 last = map->last_port - map->first_port;
+
+	/* We run parallel with other readers (test element)
+	 * but adding/deleting new entries is locked out */
+	read_lock_bh(&set->lock);
+	for (id = 0; id <= last; id++)
+		if (ip_set_timeout_expired(table[id]))
+			table[id] = IPSET_ELEM_UNSET;
+	read_unlock_bh(&set->lock);
+
+	map->gc.expires = jiffies + IPSET_GC_PERIOD(map->timeout) * HZ;
+	add_timer(&map->gc);
+}
+
+static void
+bitmap_port_gc_init(struct ip_set *set)
+{
+	struct bitmap_port *map = set->data;
+
+	init_timer(&map->gc);
+	map->gc.data = (unsigned long) set;
+	map->gc.function = bitmap_port_gc;
+	map->gc.expires = jiffies + IPSET_GC_PERIOD(map->timeout) * HZ;
+	add_timer(&map->gc);
+}
+
+/* Create bitmap:ip type of sets */
+
+static bool
+init_map_port(struct ip_set *set, struct bitmap_port *map,
+	      u16 first_port, u16 last_port)
+{
+	map->members = ip_set_alloc(map->memsize);
+	if (!map->members)
+		return false;
+	map->first_port = first_port;
+	map->last_port = last_port;
+	map->timeout = IPSET_NO_TIMEOUT;
+
+	set->data = map;
+	set->family = AF_UNSPEC;
+
+	return true;
+}
+
+static int
+bitmap_port_create(struct ip_set *set, struct nlattr *tb[],
+		 u32 flags)
+{
+	struct bitmap_port *map;
+	u16 first_port, last_port;
+
+	if (unlikely(!ip_set_attr_netorder(tb, IPSET_ATTR_PORT) ||
+		     !ip_set_attr_netorder(tb, IPSET_ATTR_PORT_TO) ||
+		     !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT)))
+		return -IPSET_ERR_PROTOCOL;
+
+	first_port = ip_set_get_h16(tb[IPSET_ATTR_PORT]);
+	last_port = ip_set_get_h16(tb[IPSET_ATTR_PORT_TO]);
+	if (first_port > last_port) {
+		u16 tmp = first_port;
+
+		first_port = last_port;
+		last_port = tmp;
+	}
+
+	map = kzalloc(sizeof(*map), GFP_KERNEL);
+	if (!map)
+		return -ENOMEM;
+
+	if (tb[IPSET_ATTR_TIMEOUT]) {
+		map->memsize = (last_port - first_port + 1)
+			       * sizeof(unsigned long);
+
+		if (!init_map_port(set, map, first_port, last_port)) {
+			kfree(map);
+			return -ENOMEM;
+		}
+
+		map->timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
+		set->variant = &bitmap_tport;
+
+		bitmap_port_gc_init(set);
+	} else {
+		map->memsize = bitmap_bytes(0, last_port - first_port);
+		pr_debug("memsize: %zu\n", map->memsize);
+		if (!init_map_port(set, map, first_port, last_port)) {
+			kfree(map);
+			return -ENOMEM;
+		}
+
+		set->variant = &bitmap_port;
+	}
+	return 0;
+}
+
+static struct ip_set_type bitmap_port_type = {
+	.name		= "bitmap:port",
+	.protocol	= IPSET_PROTOCOL,
+	.features	= IPSET_TYPE_PORT,
+	.dimension	= IPSET_DIM_ONE,
+	.family		= AF_UNSPEC,
+	.revision	= 0,
+	.create		= bitmap_port_create,
+	.create_policy	= {
+		[IPSET_ATTR_PORT]	= { .type = NLA_U16 },
+		[IPSET_ATTR_PORT_TO]	= { .type = NLA_U16 },
+		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
+	},
+	.adt_policy	= {
+		[IPSET_ATTR_PORT]	= { .type = NLA_U16 },
+		[IPSET_ATTR_PORT_TO]	= { .type = NLA_U16 },
+		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
+		[IPSET_ATTR_LINENO]	= { .type = NLA_U32 },
+	},
+	.me		= THIS_MODULE,
+};
+
+static int __init
+bitmap_port_init(void)
+{
+	return ip_set_type_register(&bitmap_port_type);
+}
+
+static void __exit
+bitmap_port_fini(void)
+{
+	ip_set_type_unregister(&bitmap_port_type);
+}
+
+module_init(bitmap_port_init);
+module_exit(bitmap_port_fini);