[net-next-2.6.git] / include / linux / filter.h

/*
 * Linux Socket Filter Data Structures
 */

#ifndef __LINUX_FILTER_H__
#define __LINUX_FILTER_H__

#include <linux/compiler.h>
#include <linux/types.h>

#ifdef __KERNEL__
#include <asm/atomic.h>
#endif

/*
 * Current version of the filter code architecture.
 */
#define BPF_MAJOR_VERSION 1
#define BPF_MINOR_VERSION 1

/*
 *	Try and keep these values and structures similar to BSD, especially
 *	the BPF code definitions which need to match so you can share filters
 */
 
struct sock_filter {	/* Filter block */
	__u16	code;   /* Actual filter code */
	__u8	jt;	/* Jump true */
	__u8	jf;	/* Jump false */
	__u32	k;      /* Generic multiuse field */
};

struct sock_fprog {	/* Required for SO_ATTACH_FILTER. */
	unsigned short		len;	/* Number of filter blocks */
	struct sock_filter __user *filter;
};

/*
 * Instruction classes
 */

#define BPF_CLASS(code) ((code) & 0x07)
#define         BPF_LD          0x00
#define         BPF_LDX         0x01
#define         BPF_ST          0x02
#define         BPF_STX         0x03
#define         BPF_ALU         0x04
#define         BPF_JMP         0x05
#define         BPF_RET         0x06
#define         BPF_MISC        0x07

/* ld/ldx fields */
#define BPF_SIZE(code)  ((code) & 0x18)
#define         BPF_W           0x00
#define         BPF_H           0x08
#define         BPF_B           0x10
#define BPF_MODE(code)  ((code) & 0xe0)
#define         BPF_IMM         0x00
#define         BPF_ABS         0x20
#define         BPF_IND         0x40
#define         BPF_MEM         0x60
#define         BPF_LEN         0x80
#define         BPF_MSH         0xa0

/* alu/jmp fields */
#define BPF_OP(code)    ((code) & 0xf0)
#define         BPF_ADD         0x00
#define         BPF_SUB         0x10
#define         BPF_MUL         0x20
#define         BPF_DIV         0x30
#define         BPF_OR          0x40
#define         BPF_AND         0x50
#define         BPF_LSH         0x60
#define         BPF_RSH         0x70
#define         BPF_NEG         0x80
#define         BPF_JA          0x00
#define         BPF_JEQ         0x10
#define         BPF_JGT         0x20
#define         BPF_JGE         0x30
#define         BPF_JSET        0x40
#define BPF_SRC(code)   ((code) & 0x08)
#define         BPF_K           0x00
#define         BPF_X           0x08

/* ret - BPF_K and BPF_X also apply */
#define BPF_RVAL(code)  ((code) & 0x18)
#define         BPF_A           0x10

/* misc */
#define BPF_MISCOP(code) ((code) & 0xf8)
#define         BPF_TAX         0x00
#define         BPF_TXA         0x80

#ifndef BPF_MAXINSNS
#define BPF_MAXINSNS 4096
#endif

/*
 * Macros for filter block array initializers.
 */
#ifndef BPF_STMT
#define BPF_STMT(code, k) { (unsigned short)(code), 0, 0, k }
#endif
#ifndef BPF_JUMP
#define BPF_JUMP(code, k, jt, jf) { (unsigned short)(code), jt, jf, k }
#endif

/*
 * Number of scratch memory words for: BPF_ST and BPF_STX
 */
#define BPF_MEMWORDS 16

/* RATIONALE. Negative offsets are invalid in BPF.
   We use them to reference ancillary data.
   Unlike introduction new instructions, it does not break
   existing compilers/optimizers.
 */
#define SKF_AD_OFF    (-0x1000)
#define SKF_AD_PROTOCOL 0
#define SKF_AD_PKTTYPE 	4
#define SKF_AD_IFINDEX 	8
#define SKF_AD_NLATTR	12
#define SKF_AD_NLATTR_NEST	16
#define SKF_AD_MARK 	20
#define SKF_AD_QUEUE	24
#define SKF_AD_HATYPE	28
#define SKF_AD_MAX	32
#define SKF_NET_OFF   (-0x100000)
#define SKF_LL_OFF    (-0x200000)

#ifdef __KERNEL__
struct sk_filter
{
	atomic_t		refcnt;
	unsigned int         	len;	/* Number of filter blocks */
	struct rcu_head		rcu;
	struct sock_filter     	insns[0];
};

static inline unsigned int sk_filter_len(const struct sk_filter *fp)
{
	return fp->len * sizeof(struct sock_filter) + sizeof(*fp);
}

struct sk_buff;
struct sock;

extern int sk_filter(struct sock *sk, struct sk_buff *skb);
extern unsigned int sk_run_filter(struct sk_buff *skb,
				  const struct sock_filter *filter);
extern int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
extern int sk_detach_filter(struct sock *sk);
extern int sk_chk_filter(struct sock_filter *filter, int flen);
#endif /* __KERNEL__ */

#endif /* __LINUX_FILTER_H__ */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Linux Socket Filter Data Structures
	3	*/
	4
	5	#ifndef __LINUX_FILTER_H__
	6	#define __LINUX_FILTER_H__
	7
	8	#include <linux/compiler.h>
	9	#include <linux/types.h>
	10
	11	#ifdef __KERNEL__
	12	#include <asm/atomic.h>
	13	#endif
	14
	15	/*
	16	* Current version of the filter code architecture.
	17	*/
	18	#define BPF_MAJOR_VERSION 1
	19	#define BPF_MINOR_VERSION 1
	20
	21	/*
	22	* Try and keep these values and structures similar to BSD, especially
	23	* the BPF code definitions which need to match so you can share filters
	24	*/
	25
d94d9fee	26	struct sock_filter { /* Filter block */
fda9ef5d DM	27	__u16 code; /* Actual filter code */
	28	__u8 jt; /* Jump true */
	29	__u8 jf; /* Jump false */
	30	__u32 k; /* Generic multiuse field */
1da177e4 LT	31	};
1da177e4 LT	32
d94d9fee	33	struct sock_fprog { /* Required for SO_ATTACH_FILTER. */
1da177e4 LT	34	unsigned short len; /* Number of filter blocks */
	35	struct sock_filter __user *filter;
	36	};
	37
1da177e4 LT	38	/*
	39	* Instruction classes
	40	*/
	41
	42	#define BPF_CLASS(code) ((code) & 0x07)
	43	#define BPF_LD 0x00
	44	#define BPF_LDX 0x01
	45	#define BPF_ST 0x02
	46	#define BPF_STX 0x03
	47	#define BPF_ALU 0x04
	48	#define BPF_JMP 0x05
	49	#define BPF_RET 0x06
	50	#define BPF_MISC 0x07
	51
	52	/* ld/ldx fields */
	53	#define BPF_SIZE(code) ((code) & 0x18)
	54	#define BPF_W 0x00
	55	#define BPF_H 0x08
	56	#define BPF_B 0x10
	57	#define BPF_MODE(code) ((code) & 0xe0)
	58	#define BPF_IMM 0x00
	59	#define BPF_ABS 0x20
	60	#define BPF_IND 0x40
	61	#define BPF_MEM 0x60
	62	#define BPF_LEN 0x80
	63	#define BPF_MSH 0xa0
	64
	65	/* alu/jmp fields */
	66	#define BPF_OP(code) ((code) & 0xf0)
	67	#define BPF_ADD 0x00
	68	#define BPF_SUB 0x10
	69	#define BPF_MUL 0x20
	70	#define BPF_DIV 0x30
	71	#define BPF_OR 0x40
	72	#define BPF_AND 0x50
	73	#define BPF_LSH 0x60
	74	#define BPF_RSH 0x70
	75	#define BPF_NEG 0x80
	76	#define BPF_JA 0x00
	77	#define BPF_JEQ 0x10
	78	#define BPF_JGT 0x20
	79	#define BPF_JGE 0x30
	80	#define BPF_JSET 0x40
	81	#define BPF_SRC(code) ((code) & 0x08)
	82	#define BPF_K 0x00
	83	#define BPF_X 0x08
	84
	85	/* ret - BPF_K and BPF_X also apply */
	86	#define BPF_RVAL(code) ((code) & 0x18)
	87	#define BPF_A 0x10
	88
	89	/* misc */
	90	#define BPF_MISCOP(code) ((code) & 0xf8)
	91	#define BPF_TAX 0x00
	92	#define BPF_TXA 0x80
	93
	94	#ifndef BPF_MAXINSNS
	95	#define BPF_MAXINSNS 4096
	96	#endif
	97
	98	/*
	99	* Macros for filter block array initializers.
	100	*/
	101	#ifndef BPF_STMT
102	#define BPF_STMT(code, k) { (unsigned short)(code), 0, 0, k }
103	#endif
104	#ifndef BPF_JUMP
105	#define BPF_JUMP(code, k, jt, jf) { (unsigned short)(code), jt, jf, k }
106	#endif
107
108	/*
109	* Number of scratch memory words for: BPF_ST and BPF_STX
110	*/
111	#define BPF_MEMWORDS 16
112
113	/* RATIONALE. Negative offsets are invalid in BPF.
114	We use them to reference ancillary data.
115	Unlike introduction new instructions, it does not break
116	existing compilers/optimizers.
117	*/
118	#define SKF_AD_OFF (-0x1000)
119	#define SKF_AD_PROTOCOL 0
120	#define SKF_AD_PKTTYPE 4
121	#define SKF_AD_IFINDEX 8
4738c1db	122	#define SKF_AD_NLATTR 12
d214c753	123	#define SKF_AD_NLATTR_NEST 16
7e75f93e	124	#define SKF_AD_MARK 20
d19742fb	125	#define SKF_AD_QUEUE 24
40eaf962 PLE	126	#define SKF_AD_HATYPE 28
40eaf962 PLE	127	#define SKF_AD_MAX 32
1da177e4 LT	128	#define SKF_NET_OFF (-0x100000)
	129	#define SKF_LL_OFF (-0x200000)
	130
	131	#ifdef __KERNEL__
b715631f SH	132	struct sk_filter
	133	{
	134	atomic_t refcnt;
	135	unsigned int len; /* Number of filter blocks */
	136	struct rcu_head rcu;
	137	struct sock_filter insns[0];
	138	};
	139
	140	static inline unsigned int sk_filter_len(const struct sk_filter *fp)
	141	{
	142	return fp->len * sizeof(struct sock_filter) + sizeof(*fp);
	143	}
	144
1da177e4 LT	145	struct sk_buff;
	146	struct sock;
	147
43db6d65	148	extern int sk_filter(struct sock sk, struct sk_buff skb);
b715631f	149	extern unsigned int sk_run_filter(struct sk_buff *skb,
93aaae2e	150	const struct sock_filter *filter);
1da177e4	151	extern int sk_attach_filter(struct sock_fprog fprog, struct sock sk);
55b33325	152	extern int sk_detach_filter(struct sock *sk);
1da177e4 LT	153	extern int sk_chk_filter(struct sock_filter *filter, int flen);
	154	#endif /* __KERNEL__ */
	155
	156	#endif /* __LINUX_FILTER_H__ */