netfilter: ipset: hash:net set type support

The module implements the hash:net type support in four flavours:
for IPv4 and IPv6, both without and with timeout support. The elements
are one dimensional: IPv4/IPv6 network address/prefixes.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Patrick McHardy <kaber@trash.net>

3 files changed, 471 insertions, 0 deletions

diff --git a/net/netfilter/ipset/Kconfig b/net/netfilter/ipset/Kconfig
index e2fbaa9d902..8d85de00e9e 100644
--- a/net/netfilter/ipset/Kconfig
+++ b/net/netfilter/ipset/Kconfig
@@ -89,4 +89,13 @@ config IP_SET_HASH_IPPORTNET
 
 	  To compile it as a module, choose M here.  If unsure, say N.
 
+config IP_SET_HASH_NET
+	tristate "hash:net set support"
+	depends on IP_SET
+	help
+	  This option adds the hash:net set type support, by which
+	  one can store IPv4/IPv6 network address/prefix elements in a set.
+
+	  To compile it as a module, choose M here.  If unsure, say N.
+
 endif # IP_SET
diff --git a/net/netfilter/ipset/Makefile b/net/netfilter/ipset/Makefile
index 9c5d857511c..fd5eeb6a7e5 100644
--- a/net/netfilter/ipset/Makefile
+++ b/net/netfilter/ipset/Makefile
@@ -17,3 +17,4 @@ obj-$(CONFIG_IP_SET_HASH_IP) += ip_set_hash_ip.o
 obj-$(CONFIG_IP_SET_HASH_IPPORT) += ip_set_hash_ipport.o
 obj-$(CONFIG_IP_SET_HASH_IPPORTIP) += ip_set_hash_ipportip.o
 obj-$(CONFIG_IP_SET_HASH_IPPORTNET) += ip_set_hash_ipportnet.o
+obj-$(CONFIG_IP_SET_HASH_NET) += ip_set_hash_net.o
diff --git a/net/netfilter/ipset/ip_set_hash_net.c b/net/netfilter/ipset/ip_set_hash_net.c
new file mode 100644
index 00000000000..fb0e6a68d13
--- /dev/null
+++ b/net/netfilter/ipset/ip_set_hash_net.c
@@ -0,0 +1,461 @@
+/* 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 hash:net type */
+
+#include <linux/jhash.h>
+#include <linux/module.h>
+#include <linux/ip.h>
+#include <linux/skbuff.h>
+#include <linux/errno.h>
+#include <linux/uaccess.h>
+#include <linux/bitops.h>
+#include <linux/spinlock.h>
+#include <linux/random.h>
+#include <net/ip.h>
+#include <net/ipv6.h>
+#include <net/netlink.h>
+
+#include <linux/netfilter.h>
+#include <linux/netfilter/ipset/pfxlen.h>
+#include <linux/netfilter/ipset/ip_set.h>
+#include <linux/netfilter/ipset/ip_set_timeout.h>
+#include <linux/netfilter/ipset/ip_set_hash.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
+MODULE_DESCRIPTION("hash:net type of IP sets");
+MODULE_ALIAS("ip_set_hash:net");
+
+/* Type specific function prefix */
+#define TYPE		hash_net
+
+static bool
+hash_net_same_set(const struct ip_set *a, const struct ip_set *b);
+
+#define hash_net4_same_set	hash_net_same_set
+#define hash_net6_same_set	hash_net_same_set
+
+/* The type variant functions: IPv4 */
+
+/* Member elements without timeout */
+struct hash_net4_elem {
+	__be32 ip;
+	u16 padding0;
+	u8 padding1;
+	u8 cidr;
+};
+
+/* Member elements with timeout support */
+struct hash_net4_telem {
+	__be32 ip;
+	u16 padding0;
+	u8 padding1;
+	u8 cidr;
+	unsigned long timeout;
+};
+
+static inline bool
+hash_net4_data_equal(const struct hash_net4_elem *ip1,
+		    const struct hash_net4_elem *ip2)
+{
+	return ip1->ip == ip2->ip && ip1->cidr == ip2->cidr;
+}
+
+static inline bool
+hash_net4_data_isnull(const struct hash_net4_elem *elem)
+{
+	return elem->cidr == 0;
+}
+
+static inline void
+hash_net4_data_copy(struct hash_net4_elem *dst,
+		    const struct hash_net4_elem *src)
+{
+	dst->ip = src->ip;
+	dst->cidr = src->cidr;
+}
+
+static inline void
+hash_net4_data_netmask(struct hash_net4_elem *elem, u8 cidr)
+{
+	elem->ip &= ip_set_netmask(cidr);
+	elem->cidr = cidr;
+}
+
+/* Zero CIDR values cannot be stored */
+static inline void
+hash_net4_data_zero_out(struct hash_net4_elem *elem)
+{
+	elem->cidr = 0;
+}
+
+static bool
+hash_net4_data_list(struct sk_buff *skb, const struct hash_net4_elem *data)
+{
+	NLA_PUT_IPADDR4(skb, IPSET_ATTR_IP, data->ip);
+	NLA_PUT_U8(skb, IPSET_ATTR_CIDR, data->cidr);
+	return 0;
+
+nla_put_failure:
+	return 1;
+}
+
+static bool
+hash_net4_data_tlist(struct sk_buff *skb, const struct hash_net4_elem *data)
+{
+	const struct hash_net4_telem *tdata =
+		(const struct hash_net4_telem *)data;
+
+	NLA_PUT_IPADDR4(skb, IPSET_ATTR_IP, tdata->ip);
+	NLA_PUT_U8(skb, IPSET_ATTR_CIDR, tdata->cidr);
+	NLA_PUT_NET32(skb, IPSET_ATTR_TIMEOUT,
+		      htonl(ip_set_timeout_get(tdata->timeout)));
+
+	return 0;
+
+nla_put_failure:
+	return 1;
+}
+
+#define IP_SET_HASH_WITH_NETS
+
+#define PF		4
+#define HOST_MASK	32
+#include <linux/netfilter/ipset/ip_set_ahash.h>
+
+static int
+hash_net4_kadt(struct ip_set *set, const struct sk_buff *skb,
+	       enum ipset_adt adt, u8 pf, u8 dim, u8 flags)
+{
+	const struct ip_set_hash *h = set->data;
+	ipset_adtfn adtfn = set->variant->adt[adt];
+	struct hash_net4_elem data = { .cidr = h->nets[0].cidr || HOST_MASK };
+
+	if (data.cidr == 0)
+		return -EINVAL;
+	if (adt == IPSET_TEST)
+		data.cidr = HOST_MASK;
+
+	ip4addrptr(skb, flags & IPSET_DIM_ONE_SRC, &data.ip);
+	data.ip &= ip_set_netmask(data.cidr);
+
+	return adtfn(set, &data, h->timeout);
+}
+
+static int
+hash_net4_uadt(struct ip_set *set, struct nlattr *tb[],
+	       enum ipset_adt adt, u32 *lineno, u32 flags)
+{
+	const struct ip_set_hash *h = set->data;
+	ipset_adtfn adtfn = set->variant->adt[adt];
+	struct hash_net4_elem data = { .cidr = HOST_MASK };
+	u32 timeout = h->timeout;
+	int ret;
+
+	if (unlikely(!tb[IPSET_ATTR_IP] ||
+		     !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]);
+
+	ret = ip_set_get_ipaddr4(tb[IPSET_ATTR_IP], &data.ip);
+	if (ret)
+		return ret;
+
+	if (tb[IPSET_ATTR_CIDR])
+		data.cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
+
+	if (!data.cidr)
+		return -IPSET_ERR_INVALID_CIDR;
+
+	data.ip &= ip_set_netmask(data.cidr);
+
+	if (tb[IPSET_ATTR_TIMEOUT]) {
+		if (!with_timeout(h->timeout))
+			return -IPSET_ERR_TIMEOUT;
+		timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
+	}
+
+	ret = adtfn(set, &data, timeout);
+
+	return ip_set_eexist(ret, flags) ? 0 : ret;
+}
+
+static bool
+hash_net_same_set(const struct ip_set *a, const struct ip_set *b)
+{
+	const struct ip_set_hash *x = a->data;
+	const struct ip_set_hash *y = b->data;
+
+	/* Resizing changes htable_bits, so we ignore it */
+	return x->maxelem == y->maxelem &&
+	       x->timeout == y->timeout;
+}
+
+/* The type variant functions: IPv6 */
+
+struct hash_net6_elem {
+	union nf_inet_addr ip;
+	u16 padding0;
+	u8 padding1;
+	u8 cidr;
+};
+
+struct hash_net6_telem {
+	union nf_inet_addr ip;
+	u16 padding0;
+	u8 padding1;
+	u8 cidr;
+	unsigned long timeout;
+};
+
+static inline bool
+hash_net6_data_equal(const struct hash_net6_elem *ip1,
+		     const struct hash_net6_elem *ip2)
+{
+	return ipv6_addr_cmp(&ip1->ip.in6, &ip2->ip.in6) == 0 &&
+	       ip1->cidr == ip2->cidr;
+}
+
+static inline bool
+hash_net6_data_isnull(const struct hash_net6_elem *elem)
+{
+	return elem->cidr == 0;
+}
+
+static inline void
+hash_net6_data_copy(struct hash_net6_elem *dst,
+		    const struct hash_net6_elem *src)
+{
+	ipv6_addr_copy(&dst->ip.in6, &src->ip.in6);
+	dst->cidr = src->cidr;
+}
+
+static inline void
+hash_net6_data_zero_out(struct hash_net6_elem *elem)
+{
+	elem->cidr = 0;
+}
+
+static inline void
+ip6_netmask(union nf_inet_addr *ip, u8 prefix)
+{
+	ip->ip6[0] &= ip_set_netmask6(prefix)[0];
+	ip->ip6[1] &= ip_set_netmask6(prefix)[1];
+	ip->ip6[2] &= ip_set_netmask6(prefix)[2];
+	ip->ip6[3] &= ip_set_netmask6(prefix)[3];
+}
+
+static inline void
+hash_net6_data_netmask(struct hash_net6_elem *elem, u8 cidr)
+{
+	ip6_netmask(&elem->ip, cidr);
+	elem->cidr = cidr;
+}
+
+static bool
+hash_net6_data_list(struct sk_buff *skb, const struct hash_net6_elem *data)
+{
+	NLA_PUT_IPADDR6(skb, IPSET_ATTR_IP, &data->ip);
+	NLA_PUT_U8(skb, IPSET_ATTR_CIDR, data->cidr);
+	return 0;
+
+nla_put_failure:
+	return 1;
+}
+
+static bool
+hash_net6_data_tlist(struct sk_buff *skb, const struct hash_net6_elem *data)
+{
+	const struct hash_net6_telem *e =
+		(const struct hash_net6_telem *)data;
+
+	NLA_PUT_IPADDR6(skb, IPSET_ATTR_IP, &e->ip);
+	NLA_PUT_U8(skb, IPSET_ATTR_CIDR, e->cidr);
+	NLA_PUT_NET32(skb, IPSET_ATTR_TIMEOUT,
+		      htonl(ip_set_timeout_get(e->timeout)));
+	return 0;
+
+nla_put_failure:
+	return 1;
+}
+
+#undef PF
+#undef HOST_MASK
+
+#define PF		6
+#define HOST_MASK	128
+#include <linux/netfilter/ipset/ip_set_ahash.h>
+
+static int
+hash_net6_kadt(struct ip_set *set, const struct sk_buff *skb,
+	       enum ipset_adt adt, u8 pf, u8 dim, u8 flags)
+{
+	const struct ip_set_hash *h = set->data;
+	ipset_adtfn adtfn = set->variant->adt[adt];
+	struct hash_net6_elem data = { .cidr = h->nets[0].cidr || HOST_MASK };
+
+	if (data.cidr == 0)
+		return -EINVAL;
+	if (adt == IPSET_TEST)
+		data.cidr = HOST_MASK;
+
+	ip6addrptr(skb, flags & IPSET_DIM_ONE_SRC, &data.ip.in6);
+	ip6_netmask(&data.ip, data.cidr);
+
+	return adtfn(set, &data, h->timeout);
+}
+
+static int
+hash_net6_uadt(struct ip_set *set, struct nlattr *tb[],
+	       enum ipset_adt adt, u32 *lineno, u32 flags)
+{
+	const struct ip_set_hash *h = set->data;
+	ipset_adtfn adtfn = set->variant->adt[adt];
+	struct hash_net6_elem data = { .cidr = HOST_MASK };
+	u32 timeout = h->timeout;
+	int ret;
+
+	if (unlikely(!tb[IPSET_ATTR_IP] ||
+		     !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]);
+
+	ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP], &data.ip);
+	if (ret)
+		return ret;
+
+	if (tb[IPSET_ATTR_CIDR])
+		data.cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
+
+	if (!data.cidr)
+		return -IPSET_ERR_INVALID_CIDR;
+
+	ip6_netmask(&data.ip, data.cidr);
+
+	if (tb[IPSET_ATTR_TIMEOUT]) {
+		if (!with_timeout(h->timeout))
+			return -IPSET_ERR_TIMEOUT;
+		timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
+	}
+
+	ret = adtfn(set, &data, timeout);
+
+	return ip_set_eexist(ret, flags) ? 0 : ret;
+}
+
+/* Create hash:ip type of sets */
+
+static int
+hash_net_create(struct ip_set *set, struct nlattr *tb[], u32 flags)
+{
+	u32 hashsize = IPSET_DEFAULT_HASHSIZE, maxelem = IPSET_DEFAULT_MAXELEM;
+	struct ip_set_hash *h;
+	u8 hbits;
+
+	if (!(set->family == AF_INET || set->family == AF_INET6))
+		return -IPSET_ERR_INVALID_FAMILY;
+
+	if (unlikely(!ip_set_optattr_netorder(tb, IPSET_ATTR_HASHSIZE) ||
+		     !ip_set_optattr_netorder(tb, IPSET_ATTR_MAXELEM) ||
+		     !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT)))
+		return -IPSET_ERR_PROTOCOL;
+
+	if (tb[IPSET_ATTR_HASHSIZE]) {
+		hashsize = ip_set_get_h32(tb[IPSET_ATTR_HASHSIZE]);
+		if (hashsize < IPSET_MIMINAL_HASHSIZE)
+			hashsize = IPSET_MIMINAL_HASHSIZE;
+	}
+
+	if (tb[IPSET_ATTR_MAXELEM])
+		maxelem = ip_set_get_h32(tb[IPSET_ATTR_MAXELEM]);
+
+	h = kzalloc(sizeof(*h)
+		    + sizeof(struct ip_set_hash_nets)
+		      * (set->family == AF_INET ? 32 : 128), GFP_KERNEL);
+	if (!h)
+		return -ENOMEM;
+
+	h->maxelem = maxelem;
+	get_random_bytes(&h->initval, sizeof(h->initval));
+	h->timeout = IPSET_NO_TIMEOUT;
+
+	hbits = htable_bits(hashsize);
+	h->table = ip_set_alloc(
+			sizeof(struct htable)
+			+ jhash_size(hbits) * sizeof(struct hbucket));
+	if (!h->table) {
+		kfree(h);
+		return -ENOMEM;
+	}
+	h->table->htable_bits = hbits;
+
+	set->data = h;
+
+	if (tb[IPSET_ATTR_TIMEOUT]) {
+		h->timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
+
+		set->variant = set->family == AF_INET
+			? &hash_net4_tvariant : &hash_net6_tvariant;
+
+		if (set->family == AF_INET)
+			hash_net4_gc_init(set);
+		else
+			hash_net6_gc_init(set);
+	} else {
+		set->variant = set->family == AF_INET
+			? &hash_net4_variant : &hash_net6_variant;
+	}
+
+	pr_debug("create %s hashsize %u (%u) maxelem %u: %p(%p)\n",
+		 set->name, jhash_size(h->table->htable_bits),
+		 h->table->htable_bits, h->maxelem, set->data, h->table);
+
+	return 0;
+}
+
+static struct ip_set_type hash_net_type __read_mostly = {
+	.name		= "hash:net",
+	.protocol	= IPSET_PROTOCOL,
+	.features	= IPSET_TYPE_IP,
+	.dimension	= IPSET_DIM_ONE,
+	.family		= AF_UNSPEC,
+	.revision	= 0,
+	.create		= hash_net_create,
+	.create_policy	= {
+		[IPSET_ATTR_HASHSIZE]	= { .type = NLA_U32 },
+		[IPSET_ATTR_MAXELEM]	= { .type = NLA_U32 },
+		[IPSET_ATTR_PROBES]	= { .type = NLA_U8 },
+		[IPSET_ATTR_RESIZE]	= { .type = NLA_U8  },
+		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
+	},
+	.adt_policy	= {
+		[IPSET_ATTR_IP]		= { .type = NLA_NESTED },
+		[IPSET_ATTR_CIDR]	= { .type = NLA_U8 },
+		[IPSET_ATTR_TIMEOUT]	= { .type = NLA_U32 },
+	},
+	.me		= THIS_MODULE,
+};
+
+static int __init
+hash_net_init(void)
+{
+	return ip_set_type_register(&hash_net_type);
+}
+
+static void __exit
+hash_net_fini(void)
+{
+	ip_set_type_unregister(&hash_net_type);
+}
+
+module_init(hash_net_init);
+module_exit(hash_net_fini);