[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / netfilter / nf_conntrack_labels.c

/*
 * test/set flag bits stored in conntrack extension area.
 *
 * (C) 2013 Astaro GmbH & Co KG
 *
 * 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.
 */

#include <linux/ctype.h>
#include <linux/export.h>
#include <linux/jhash.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <linux/slab.h>

#include <net/netfilter/nf_conntrack_ecache.h>
#include <net/netfilter/nf_conntrack_labels.h>

static unsigned int label_bits(const struct nf_conn_labels *l)
{
	unsigned int longs = l->words;
	return longs * BITS_PER_LONG;
}

bool nf_connlabel_match(const struct nf_conn *ct, u16 bit)
{
	struct nf_conn_labels *labels = nf_ct_labels_find(ct);

	if (!labels)
		return false;

	return bit < label_bits(labels) && test_bit(bit, labels->bits);
}
EXPORT_SYMBOL_GPL(nf_connlabel_match);

int nf_connlabel_set(struct nf_conn *ct, u16 bit)
{
	struct nf_conn_labels *labels = nf_ct_labels_find(ct);

	if (!labels || bit >= label_bits(labels))
		return -ENOSPC;

	if (test_bit(bit, labels->bits))
		return 0;

	if (!test_and_set_bit(bit, labels->bits))
		nf_conntrack_event_cache(IPCT_LABEL, ct);

	return 0;
}
EXPORT_SYMBOL_GPL(nf_connlabel_set);

#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
static void replace_u32(u32 *address, u32 mask, u32 new)
{
	u32 old, tmp;

	do {
		old = *address;
		tmp = (old & mask) ^ new;
	} while (cmpxchg(address, old, tmp) != old);
}

int nf_connlabels_replace(struct nf_conn *ct,
			  const u32 *data,
			  const u32 *mask, unsigned int words32)
{
	struct nf_conn_labels *labels;
	unsigned int size, i;
	u32 *dst;

	labels = nf_ct_labels_find(ct);
	if (!labels)
		return -ENOSPC;

	size = labels->words * sizeof(long);
	if (size < (words32 * sizeof(u32)))
		words32 = size / sizeof(u32);

	dst = (u32 *) labels->bits;
	if (words32) {
		for (i = 0; i < words32; i++)
			replace_u32(&dst[i], mask ? ~mask[i] : 0, data[i]);
	}

	size /= sizeof(u32);
	for (i = words32; i < size; i++) /* pad */
		replace_u32(&dst[i], 0, 0);

	nf_conntrack_event_cache(IPCT_LABEL, ct);
	return 0;
}
EXPORT_SYMBOL_GPL(nf_connlabels_replace);
#endif

static struct nf_ct_ext_type labels_extend __read_mostly = {
	.len    = sizeof(struct nf_conn_labels),
	.align  = __alignof__(struct nf_conn_labels),
	.id     = NF_CT_EXT_LABELS,
};

int nf_conntrack_labels_init(void)
{
	return nf_ct_extend_register(&labels_extend);
}

void nf_conntrack_labels_fini(void)
{
	nf_ct_extend_unregister(&labels_extend);
}
Commit	Line	Data
c539f017 FW	1	/*
	2	* test/set flag bits stored in conntrack extension area.
	3	*
	4	* (C) 2013 Astaro GmbH & Co KG
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation.
	9	*/
	10
	11	#include <linux/ctype.h>
	12	#include <linux/export.h>
	13	#include <linux/jhash.h>
	14	#include <linux/spinlock.h>
	15	#include <linux/types.h>
	16	#include <linux/slab.h>
	17
	18	#include <net/netfilter/nf_conntrack_ecache.h>
	19	#include <net/netfilter/nf_conntrack_labels.h>
	20
	21	static unsigned int label_bits(const struct nf_conn_labels *l)
	22	{
	23	unsigned int longs = l->words;
	24	return longs * BITS_PER_LONG;
	25	}
	26
	27	bool nf_connlabel_match(const struct nf_conn *ct, u16 bit)
	28	{
	29	struct nf_conn_labels *labels = nf_ct_labels_find(ct);
	30
	31	if (!labels)
	32	return false;
	33
	34	return bit < label_bits(labels) && test_bit(bit, labels->bits);
	35	}
	36	EXPORT_SYMBOL_GPL(nf_connlabel_match);
	37
	38	int nf_connlabel_set(struct nf_conn *ct, u16 bit)
	39	{
	40	struct nf_conn_labels *labels = nf_ct_labels_find(ct);
	41
	42	if (!labels \|\| bit >= label_bits(labels))
	43	return -ENOSPC;
	44
	45	if (test_bit(bit, labels->bits))
	46	return 0;
	47
797a7d66	48	if (!test_and_set_bit(bit, labels->bits))
0ceabd83	49	nf_conntrack_event_cache(IPCT_LABEL, ct);
c539f017 FW	50
	51	return 0;
	52	}
	53	EXPORT_SYMBOL_GPL(nf_connlabel_set);
	54
9b21f6a9 FW	55	#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
	56	static void replace_u32(u32 *address, u32 mask, u32 new)
	57	{
	58	u32 old, tmp;
	59
	60	do {
	61	old = *address;
	62	tmp = (old & mask) ^ new;
	63	} while (cmpxchg(address, old, tmp) != old);
	64	}
	65
	66	int nf_connlabels_replace(struct nf_conn *ct,
	67	const u32 *data,
	68	const u32 *mask, unsigned int words32)
	69	{
	70	struct nf_conn_labels *labels;
	71	unsigned int size, i;
	72	u32 *dst;
	73
	74	labels = nf_ct_labels_find(ct);
	75	if (!labels)
	76	return -ENOSPC;
	77
	78	size = labels->words * sizeof(long);
	79	if (size < (words32 * sizeof(u32)))
	80	words32 = size / sizeof(u32);
	81
	82	dst = (u32 *) labels->bits;
	83	if (words32) {
	84	for (i = 0; i < words32; i++)
	85	replace_u32(&dst[i], mask ? ~mask[i] : 0, data[i]);
	86	}
	87
	88	size /= sizeof(u32);
	89	for (i = words32; i < size; i++) /* pad */
	90	replace_u32(&dst[i], 0, 0);
	91
	92	nf_conntrack_event_cache(IPCT_LABEL, ct);
	93	return 0;
	94	}
	95	EXPORT_SYMBOL_GPL(nf_connlabels_replace);
	96	#endif
	97
c539f017 FW	98	static struct nf_ct_ext_type labels_extend __read_mostly = {
	99	.len = sizeof(struct nf_conn_labels),
	100	.align = __alignof__(struct nf_conn_labels),
	101	.id = NF_CT_EXT_LABELS,
	102	};
	103
5f69b8f5	104	int nf_conntrack_labels_init(void)
c539f017	105	{
5f69b8f5	106	return nf_ct_extend_register(&labels_extend);
c539f017 FW	107	}
c539f017 FW	108
5f69b8f5	109	void nf_conntrack_labels_fini(void)
c539f017	110	{
5f69b8f5	111	nf_ct_extend_unregister(&labels_extend);
c539f017	112	}