Import ipset-2.3.1a-20080617

extensions/ipset/ip_set_iphash.c

@@ -0,0 +1,430 @@
+/* Copyright (C) 2003-2004 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 hash set */
+
+#include <linux/module.h>
+#include <linux/ip.h>
+#include <linux/skbuff.h>
+#include <linux/version.h>
+#include <linux/jhash.h>
+#include <linux/netfilter_ipv4/ip_tables.h>
+#include "ip_set.h"
+#include <linux/errno.h>
+#include <asm/uaccess.h>
+#include <asm/bitops.h>
+#include <linux/spinlock.h>
+#include <linux/vmalloc.h>
+#include <linux/random.h>
+
+#include <net/ip.h>
+
+#include "ip_set_malloc.h"
+#include "ip_set_iphash.h"
+
+static int limit = MAX_RANGE;
+
+static inline __u32
+jhash_ip(const struct ip_set_iphash *map, uint16_t i, ip_set_ip_t ip)
+{
+	return jhash_1word(ip, *(((uint32_t *) map->initval) + i));
+}
+
+static inline __u32
+hash_id(struct ip_set *set, ip_set_ip_t ip, ip_set_ip_t *hash_ip)
+{
+	struct ip_set_iphash *map = (struct ip_set_iphash *) set->data;
+	__u32 id;
+	u_int16_t i;
+	ip_set_ip_t *elem;
+
+	*hash_ip = ip & map->netmask;
+	DP("set: %s, ip:%u.%u.%u.%u, %u.%u.%u.%u, %u.%u.%u.%u",
+	   set->name, HIPQUAD(ip), HIPQUAD(*hash_ip), HIPQUAD(map->netmask));
+	
+	for (i = 0; i < map->probes; i++) {
+		id = jhash_ip(map, i, *hash_ip) % map->hashsize;
+		DP("hash key: %u", id);
+		elem = HARRAY_ELEM(map->members, ip_set_ip_t *, id);
+		if (*elem == *hash_ip)
+			return id;
+		/* No shortcut at testing - there can be deleted
+		 * entries. */
+	}
+	return UINT_MAX;
+}
+
+static inline int
+__testip(struct ip_set *set, ip_set_ip_t ip, ip_set_ip_t *hash_ip)
+{
+	return (ip && hash_id(set, ip, hash_ip) != UINT_MAX);
+}
+
+static int
+testip(struct ip_set *set, const void *data, size_t size,
+       ip_set_ip_t *hash_ip)
+{
+	struct ip_set_req_iphash *req = 
+	    (struct ip_set_req_iphash *) data;
+
+	if (size != sizeof(struct ip_set_req_iphash)) {
+		ip_set_printk("data length wrong (want %zu, have %zu)",
+			      sizeof(struct ip_set_req_iphash),
+			      size);
+		return -EINVAL;
+	}
+	return __testip(set, req->ip, hash_ip);
+}
+
+static int
+testip_kernel(struct ip_set *set, 
+	      const struct sk_buff *skb,
+	      ip_set_ip_t *hash_ip,
+	      const u_int32_t *flags,
+	      unsigned char index)
+{
+	return __testip(set,
+			ntohl(flags[index] & IPSET_SRC 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
+				? ip_hdr(skb)->saddr 
+				: ip_hdr(skb)->daddr),
+#else
+				? skb->nh.iph->saddr 
+				: skb->nh.iph->daddr),
+#endif
+			hash_ip);
+}
+
+static inline int
+__addip(struct ip_set_iphash *map, ip_set_ip_t ip, ip_set_ip_t *hash_ip)
+{
+	__u32 probe;
+	u_int16_t i;
+	ip_set_ip_t *elem;
+	
+	if (!ip || map->elements >= limit)
+		return -ERANGE;
+
+	*hash_ip = ip & map->netmask;
+	
+	for (i = 0; i < map->probes; i++) {
+		probe = jhash_ip(map, i, *hash_ip) % map->hashsize;
+		elem = HARRAY_ELEM(map->members, ip_set_ip_t *, probe);
+		if (*elem == *hash_ip)
+			return -EEXIST;
+		if (!*elem) {
+			*elem = *hash_ip;
+			map->elements++;
+			return 0;
+		}
+	}
+	/* Trigger rehashing */
+	return -EAGAIN;
+}
+
+static int
+addip(struct ip_set *set, const void *data, size_t size,
+        ip_set_ip_t *hash_ip)
+{
+	struct ip_set_req_iphash *req = 
+	    (struct ip_set_req_iphash *) data;
+
+	if (size != sizeof(struct ip_set_req_iphash)) {
+		ip_set_printk("data length wrong (want %zu, have %zu)",
+			      sizeof(struct ip_set_req_iphash),
+			      size);
+		return -EINVAL;
+	}
+	return __addip((struct ip_set_iphash *) set->data, req->ip, hash_ip);
+}
+
+static int
+addip_kernel(struct ip_set *set, 
+	     const struct sk_buff *skb,
+	     ip_set_ip_t *hash_ip,
+	     const u_int32_t *flags,
+	     unsigned char index)
+{
+	return __addip((struct ip_set_iphash *) set->data,
+		       ntohl(flags[index] & IPSET_SRC 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
+				? ip_hdr(skb)->saddr 
+				: ip_hdr(skb)->daddr),
+#else
+		       		? skb->nh.iph->saddr 
+				: skb->nh.iph->daddr),
+#endif
+		       hash_ip);
+}
+
+static int retry(struct ip_set *set)
+{
+	struct ip_set_iphash *map = (struct ip_set_iphash *) set->data;
+	ip_set_ip_t hash_ip, *elem;
+	void *members;
+	u_int32_t i, hashsize = map->hashsize;
+	int res;
+	struct ip_set_iphash *tmp;
+	
+	if (map->resize == 0)
+		return -ERANGE;
+
+    again:
+    	res = 0;
+    	
+	/* Calculate new hash size */
+	hashsize += (hashsize * map->resize)/100;
+	if (hashsize == map->hashsize)
+		hashsize++;
+	
+	ip_set_printk("rehashing of set %s triggered: "
+		      "hashsize grows from %u to %u",
+		      set->name, map->hashsize, hashsize);
+
+	tmp = kmalloc(sizeof(struct ip_set_iphash) 
+		      + map->probes * sizeof(uint32_t), GFP_ATOMIC);
+	if (!tmp) {
+		DP("out of memory for %d bytes",
+		   sizeof(struct ip_set_iphash)
+		   + map->probes * sizeof(uint32_t));
+		return -ENOMEM;
+	}
+	tmp->members = harray_malloc(hashsize, sizeof(ip_set_ip_t), GFP_ATOMIC);
+	if (!tmp->members) {
+		DP("out of memory for %d bytes", hashsize * sizeof(ip_set_ip_t));
+		kfree(tmp);
+		return -ENOMEM;
+	}
+	tmp->hashsize = hashsize;
+	tmp->elements = 0;
+	tmp->probes = map->probes;
+	tmp->resize = map->resize;
+	tmp->netmask = map->netmask;
+	memcpy(tmp->initval, map->initval, map->probes * sizeof(uint32_t));
+	
+	write_lock_bh(&set->lock);
+	map = (struct ip_set_iphash *) set->data; /* Play safe */
+	for (i = 0; i < map->hashsize && res == 0; i++) {
+		elem = HARRAY_ELEM(map->members, ip_set_ip_t *, i);	
+		if (*elem)
+			res = __addip(tmp, *elem, &hash_ip);
+	}
+	if (res) {
+		/* Failure, try again */
+		write_unlock_bh(&set->lock);
+		harray_free(tmp->members);
+		kfree(tmp);
+		goto again;
+	}
+	
+	/* Success at resizing! */
+	members = map->members;
+
+	map->hashsize = tmp->hashsize;
+	map->members = tmp->members;
+	write_unlock_bh(&set->lock);
+
+	harray_free(members);
+	kfree(tmp);
+
+	return 0;
+}
+
+static inline int
+__delip(struct ip_set *set, ip_set_ip_t ip, ip_set_ip_t *hash_ip)
+{
+	struct ip_set_iphash *map = (struct ip_set_iphash *) set->data;
+	ip_set_ip_t id, *elem;
+
+	if (!ip)
+		return -ERANGE;
+
+	id = hash_id(set, ip, hash_ip);
+	if (id == UINT_MAX)
+		return -EEXIST;
+		
+	elem = HARRAY_ELEM(map->members, ip_set_ip_t *, id);
+	*elem = 0;
+	map->elements--;
+
+	return 0;
+}
+
+static int
+delip(struct ip_set *set, const void *data, size_t size,
+        ip_set_ip_t *hash_ip)
+{
+	struct ip_set_req_iphash *req =
+	    (struct ip_set_req_iphash *) data;
+
+	if (size != sizeof(struct ip_set_req_iphash)) {
+		ip_set_printk("data length wrong (want %zu, have %zu)",
+			      sizeof(struct ip_set_req_iphash),
+			      size);
+		return -EINVAL;
+	}
+	return __delip(set, req->ip, hash_ip);
+}
+
+static int
+delip_kernel(struct ip_set *set, 
+	     const struct sk_buff *skb,
+	     ip_set_ip_t *hash_ip,
+	     const u_int32_t *flags,
+	     unsigned char index)
+{
+	return __delip(set,
+		       ntohl(flags[index] & IPSET_SRC 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
+				? ip_hdr(skb)->saddr 
+				: ip_hdr(skb)->daddr),
+#else
+				? skb->nh.iph->saddr 
+				: skb->nh.iph->daddr),
+#endif
+		       hash_ip);
+}
+
+static int create(struct ip_set *set, const void *data, size_t size)
+{
+	struct ip_set_req_iphash_create *req =
+	    (struct ip_set_req_iphash_create *) data;
+	struct ip_set_iphash *map;
+	uint16_t i;
+
+	if (size != sizeof(struct ip_set_req_iphash_create)) {
+		ip_set_printk("data length wrong (want %zu, have %zu)",
+			       sizeof(struct ip_set_req_iphash_create),
+			       size);
+		return -EINVAL;
+	}
+
+	if (req->hashsize < 1) {
+		ip_set_printk("hashsize too small");
+		return -ENOEXEC;
+	}
+
+	if (req->probes < 1) {
+		ip_set_printk("probes too small");
+		return -ENOEXEC;
+	}
+
+	map = kmalloc(sizeof(struct ip_set_iphash) 
+		      + req->probes * sizeof(uint32_t), GFP_KERNEL);
+	if (!map) {
+		DP("out of memory for %d bytes",
+		   sizeof(struct ip_set_iphash)
+		   + req->probes * sizeof(uint32_t));
+		return -ENOMEM;
+	}
+	for (i = 0; i < req->probes; i++)
+		get_random_bytes(((uint32_t *) map->initval)+i, 4);
+	map->elements = 0;
+	map->hashsize = req->hashsize;
+	map->probes = req->probes;
+	map->resize = req->resize;
+	map->netmask = req->netmask;
+	map->members = harray_malloc(map->hashsize, sizeof(ip_set_ip_t), GFP_KERNEL);
+	if (!map->members) {
+		DP("out of memory for %d bytes", map->hashsize * sizeof(ip_set_ip_t));
+		kfree(map);
+		return -ENOMEM;
+	}
+
+	set->data = map;
+	return 0;
+}
+
+static void destroy(struct ip_set *set)
+{
+	struct ip_set_iphash *map = (struct ip_set_iphash *) set->data;
+
+	harray_free(map->members);
+	kfree(map);
+
+	set->data = NULL;
+}
+
+static void flush(struct ip_set *set)
+{
+	struct ip_set_iphash *map = (struct ip_set_iphash *) set->data;
+	harray_flush(map->members, map->hashsize, sizeof(ip_set_ip_t));
+	map->elements = 0;
+}
+
+static void list_header(const struct ip_set *set, void *data)
+{
+	struct ip_set_iphash *map = (struct ip_set_iphash *) set->data;
+	struct ip_set_req_iphash_create *header =
+	    (struct ip_set_req_iphash_create *) data;
+
+	header->hashsize = map->hashsize;
+	header->probes = map->probes;
+	header->resize = map->resize;
+	header->netmask = map->netmask;
+}
+
+static int list_members_size(const struct ip_set *set)
+{
+	struct ip_set_iphash *map = (struct ip_set_iphash *) set->data;
+
+	return (map->hashsize * sizeof(ip_set_ip_t));
+}
+
+static void list_members(const struct ip_set *set, void *data)
+{
+	struct ip_set_iphash *map = (struct ip_set_iphash *) set->data;
+	ip_set_ip_t i, *elem;
+
+	for (i = 0; i < map->hashsize; i++) {
+		elem = HARRAY_ELEM(map->members, ip_set_ip_t *, i);	
+		((ip_set_ip_t *)data)[i] = *elem;
+	}
+}
+
+static struct ip_set_type ip_set_iphash = {
+	.typename		= SETTYPE_NAME,
+	.features		= IPSET_TYPE_IP | IPSET_DATA_SINGLE,
+	.protocol_version	= IP_SET_PROTOCOL_VERSION,
+	.create			= &create,
+	.destroy		= &destroy,
+	.flush			= &flush,
+	.reqsize		= sizeof(struct ip_set_req_iphash),
+	.addip			= &addip,
+	.addip_kernel		= &addip_kernel,
+	.retry			= &retry,
+	.delip			= &delip,
+	.delip_kernel		= &delip_kernel,
+	.testip			= &testip,
+	.testip_kernel		= &testip_kernel,
+	.header_size		= sizeof(struct ip_set_req_iphash_create),
+	.list_header		= &list_header,
+	.list_members_size	= &list_members_size,
+	.list_members		= &list_members,
+	.me			= THIS_MODULE,
+};
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
+MODULE_DESCRIPTION("iphash type of IP sets");
+module_param(limit, int, 0600);
+MODULE_PARM_DESC(limit, "maximal number of elements stored in the sets");
+
+static int __init ip_set_iphash_init(void)
+{
+	init_max_page_size();
+	return ip_set_register_set_type(&ip_set_iphash);
+}
+
+static void __exit ip_set_iphash_fini(void)
+{
+	/* FIXME: possible race with ip_set_create() */
+	ip_set_unregister_set_type(&ip_set_iphash);
+}
+
+module_init(ip_set_iphash_init);
+module_exit(ip_set_iphash_fini);