[linux-2.6-block.git] / include / linux / filter.h

/*
 * Linux Socket Filter Data Structures
 */
#ifndef __LINUX_FILTER_H__
#define __LINUX_FILTER_H__

#include <linux/atomic.h>
#include <linux/compat.h>
#include <linux/workqueue.h>
#include <uapi/linux/filter.h>

/* Internally used and optimized filter representation with extended
 * instruction set based on top of classic BPF.
 */

/* instruction classes */
#define BPF_ALU64	0x07	/* alu mode in double word width */

/* ld/ldx fields */
#define BPF_DW		0x18	/* double word */
#define BPF_XADD	0xc0	/* exclusive add */

/* alu/jmp fields */
#define BPF_MOV		0xb0	/* mov reg to reg */
#define BPF_ARSH	0xc0	/* sign extending arithmetic shift right */

/* change endianness of a register */
#define BPF_END		0xd0	/* flags for endianness conversion: */
#define BPF_TO_LE	0x00	/* convert to little-endian */
#define BPF_TO_BE	0x08	/* convert to big-endian */
#define BPF_FROM_LE	BPF_TO_LE
#define BPF_FROM_BE	BPF_TO_BE

#define BPF_JNE		0x50	/* jump != */
#define BPF_JSGT	0x60	/* SGT is signed '>', GT in x86 */
#define BPF_JSGE	0x70	/* SGE is signed '>=', GE in x86 */
#define BPF_CALL	0x80	/* function call */
#define BPF_EXIT	0x90	/* function return */

/* Placeholder/dummy for 0 */
#define BPF_0		0

/* Register numbers */
enum {
	BPF_REG_0 = 0,
	BPF_REG_1,
	BPF_REG_2,
	BPF_REG_3,
	BPF_REG_4,
	BPF_REG_5,
	BPF_REG_6,
	BPF_REG_7,
	BPF_REG_8,
	BPF_REG_9,
	BPF_REG_10,
	__MAX_BPF_REG,
};

/* BPF has 10 general purpose 64-bit registers and stack frame. */
#define MAX_BPF_REG	__MAX_BPF_REG

/* ArgX, context and stack frame pointer register positions. Note,
 * Arg1, Arg2, Arg3, etc are used as argument mappings of function
 * calls in BPF_CALL instruction.
 */
#define BPF_REG_ARG1	BPF_REG_1
#define BPF_REG_ARG2	BPF_REG_2
#define BPF_REG_ARG3	BPF_REG_3
#define BPF_REG_ARG4	BPF_REG_4
#define BPF_REG_ARG5	BPF_REG_5
#define BPF_REG_CTX	BPF_REG_6
#define BPF_REG_FP	BPF_REG_10

/* Additional register mappings for converted user programs. */
#define BPF_REG_A	BPF_REG_0
#define BPF_REG_X	BPF_REG_7
#define BPF_REG_TMP	BPF_REG_8

/* BPF program can access up to 512 bytes of stack space. */
#define MAX_BPF_STACK	512

/* Macro to invoke filter function. */
#define SK_RUN_FILTER(filter, ctx)  (*filter->bpf_func)(ctx, filter->insnsi)

struct sock_filter_int {
	__u8	code;		/* opcode */
	__u8	a_reg:4;	/* dest register */
	__u8	x_reg:4;	/* source register */
	__s16	off;		/* signed offset */
	__s32	imm;		/* signed immediate constant */
};

#ifdef CONFIG_COMPAT
/* A struct sock_filter is architecture independent. */
struct compat_sock_fprog {
	u16		len;
	compat_uptr_t	filter;	/* struct sock_filter * */
};
#endif

struct sock_fprog_kern {
	u16			len;
	struct sock_filter	*filter;
};

struct sk_buff;
struct sock;
struct seccomp_data;

struct sk_filter {
	atomic_t		refcnt;
	u32			jited:1,	/* Is our filter JIT'ed? */
				len:31;		/* Number of filter blocks */
	struct sock_fprog_kern	*orig_prog;	/* Original BPF program */
	struct rcu_head		rcu;
	unsigned int		(*bpf_func)(const struct sk_buff *skb,
					    const struct sock_filter_int *filter);
	union {
		struct sock_filter	insns[0];
		struct sock_filter_int	insnsi[0];
		struct work_struct	work;
	};
};

static inline unsigned int sk_filter_size(unsigned int proglen)
{
	return max(sizeof(struct sk_filter),
		   offsetof(struct sk_filter, insns[proglen]));
}

#define sk_filter_proglen(fprog)			\
		(fprog->len * sizeof(fprog->filter[0]))

int sk_filter(struct sock *sk, struct sk_buff *skb);

u32 sk_run_filter_int_seccomp(const struct seccomp_data *ctx,
			      const struct sock_filter_int *insni);
u32 sk_run_filter_int_skb(const struct sk_buff *ctx,
			  const struct sock_filter_int *insni);

int sk_convert_filter(struct sock_filter *prog, int len,
		      struct sock_filter_int *new_prog, int *new_len);

int sk_unattached_filter_create(struct sk_filter **pfp,
				struct sock_fprog *fprog);
void sk_unattached_filter_destroy(struct sk_filter *fp);

int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
int sk_detach_filter(struct sock *sk);

int sk_chk_filter(struct sock_filter *filter, unsigned int flen);
int sk_get_filter(struct sock *sk, struct sock_filter __user *filter,
		  unsigned int len);
void sk_decode_filter(struct sock_filter *filt, struct sock_filter *to);

void sk_filter_charge(struct sock *sk, struct sk_filter *fp);
void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp);

#ifdef CONFIG_BPF_JIT
#include <stdarg.h>
#include <linux/linkage.h>
#include <linux/printk.h>

void bpf_jit_compile(struct sk_filter *fp);
void bpf_jit_free(struct sk_filter *fp);

static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
				u32 pass, void *image)
{
	pr_err("flen=%u proglen=%u pass=%u image=%pK\n",
	       flen, proglen, pass, image);
	if (image)
		print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
			       16, 1, image, proglen, false);
}
#else
#include <linux/slab.h>
static inline void bpf_jit_compile(struct sk_filter *fp)
{
}
static inline void bpf_jit_free(struct sk_filter *fp)
{
	kfree(fp);
}
#endif

static inline int bpf_tell_extensions(void)
{
	return SKF_AD_MAX;
}

enum {
	BPF_S_RET_K = 1,
	BPF_S_RET_A,
	BPF_S_ALU_ADD_K,
	BPF_S_ALU_ADD_X,
	BPF_S_ALU_SUB_K,
	BPF_S_ALU_SUB_X,
	BPF_S_ALU_MUL_K,
	BPF_S_ALU_MUL_X,
	BPF_S_ALU_DIV_X,
	BPF_S_ALU_MOD_K,
	BPF_S_ALU_MOD_X,
	BPF_S_ALU_AND_K,
	BPF_S_ALU_AND_X,
	BPF_S_ALU_OR_K,
	BPF_S_ALU_OR_X,
	BPF_S_ALU_XOR_K,
	BPF_S_ALU_XOR_X,
	BPF_S_ALU_LSH_K,
	BPF_S_ALU_LSH_X,
	BPF_S_ALU_RSH_K,
	BPF_S_ALU_RSH_X,
	BPF_S_ALU_NEG,
	BPF_S_LD_W_ABS,
	BPF_S_LD_H_ABS,
	BPF_S_LD_B_ABS,
	BPF_S_LD_W_LEN,
	BPF_S_LD_W_IND,
	BPF_S_LD_H_IND,
	BPF_S_LD_B_IND,
	BPF_S_LD_IMM,
	BPF_S_LDX_W_LEN,
	BPF_S_LDX_B_MSH,
	BPF_S_LDX_IMM,
	BPF_S_MISC_TAX,
	BPF_S_MISC_TXA,
	BPF_S_ALU_DIV_K,
	BPF_S_LD_MEM,
	BPF_S_LDX_MEM,
	BPF_S_ST,
	BPF_S_STX,
	BPF_S_JMP_JA,
	BPF_S_JMP_JEQ_K,
	BPF_S_JMP_JEQ_X,
	BPF_S_JMP_JGE_K,
	BPF_S_JMP_JGE_X,
	BPF_S_JMP_JGT_K,
	BPF_S_JMP_JGT_X,
	BPF_S_JMP_JSET_K,
	BPF_S_JMP_JSET_X,
	/* Ancillary data */
	BPF_S_ANC_PROTOCOL,
	BPF_S_ANC_PKTTYPE,
	BPF_S_ANC_IFINDEX,
	BPF_S_ANC_NLATTR,
	BPF_S_ANC_NLATTR_NEST,
	BPF_S_ANC_MARK,
	BPF_S_ANC_QUEUE,
	BPF_S_ANC_HATYPE,
	BPF_S_ANC_RXHASH,
	BPF_S_ANC_CPU,
	BPF_S_ANC_ALU_XOR_X,
	BPF_S_ANC_VLAN_TAG,
	BPF_S_ANC_VLAN_TAG_PRESENT,
	BPF_S_ANC_PAY_OFFSET,
	BPF_S_ANC_RANDOM,
};

#endif /* __LINUX_FILTER_H__ */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Linux Socket Filter Data Structures
	3	*/
1da177e4 LT	4	#ifndef __LINUX_FILTER_H__
	5	#define __LINUX_FILTER_H__
	6
60063497	7	#include <linux/atomic.h>
0c5fe1b4	8	#include <linux/compat.h>
d45ed4a4	9	#include <linux/workqueue.h>
607ca46e	10	#include <uapi/linux/filter.h>
792d4b5c	11
bd4cf0ed AS	12	/* Internally used and optimized filter representation with extended
bd4cf0ed AS	13	* instruction set based on top of classic BPF.
0c5fe1b4	14	*/
bd4cf0ed AS	15
	16	/* instruction classes */
	17	#define BPF_ALU64 0x07 /* alu mode in double word width */
	18
	19	/* ld/ldx fields */
	20	#define BPF_DW 0x18 /* double word */
	21	#define BPF_XADD 0xc0 /* exclusive add */
	22
	23	/* alu/jmp fields */
	24	#define BPF_MOV 0xb0 /* mov reg to reg */
	25	#define BPF_ARSH 0xc0 /* sign extending arithmetic shift right */
	26
	27	/* change endianness of a register */
	28	#define BPF_END 0xd0 /* flags for endianness conversion: */
	29	#define BPF_TO_LE 0x00 /* convert to little-endian */
	30	#define BPF_TO_BE 0x08 /* convert to big-endian */
	31	#define BPF_FROM_LE BPF_TO_LE
	32	#define BPF_FROM_BE BPF_TO_BE
	33
	34	#define BPF_JNE 0x50 /* jump != */
	35	#define BPF_JSGT 0x60 /* SGT is signed '>', GT in x86 */
	36	#define BPF_JSGE 0x70 /* SGE is signed '>=', GE in x86 */
	37	#define BPF_CALL 0x80 /* function call */
	38	#define BPF_EXIT 0x90 /* function return */
	39
5bcfedf0 DB	40	/* Placeholder/dummy for 0 */
	41	#define BPF_0 0
	42
30743837 DB	43	/* Register numbers */
	44	enum {
	45	BPF_REG_0 = 0,
	46	BPF_REG_1,
	47	BPF_REG_2,
	48	BPF_REG_3,
	49	BPF_REG_4,
	50	BPF_REG_5,
	51	BPF_REG_6,
	52	BPF_REG_7,
	53	BPF_REG_8,
	54	BPF_REG_9,
	55	BPF_REG_10,
	56	__MAX_BPF_REG,
	57	};
	58
bd4cf0ed	59	/* BPF has 10 general purpose 64-bit registers and stack frame. */
30743837 DB	60	#define MAX_BPF_REG __MAX_BPF_REG
	61
	62	/* ArgX, context and stack frame pointer register positions. Note,
	63	* Arg1, Arg2, Arg3, etc are used as argument mappings of function
	64	* calls in BPF_CALL instruction.
	65	*/
	66	#define BPF_REG_ARG1 BPF_REG_1
	67	#define BPF_REG_ARG2 BPF_REG_2
	68	#define BPF_REG_ARG3 BPF_REG_3
	69	#define BPF_REG_ARG4 BPF_REG_4
	70	#define BPF_REG_ARG5 BPF_REG_5
	71	#define BPF_REG_CTX BPF_REG_6
	72	#define BPF_REG_FP BPF_REG_10
	73
	74	/* Additional register mappings for converted user programs. */
	75	#define BPF_REG_A BPF_REG_0
	76	#define BPF_REG_X BPF_REG_7
	77	#define BPF_REG_TMP BPF_REG_8
bd4cf0ed AS	78
	79	/* BPF program can access up to 512 bytes of stack space. */
	80	#define MAX_BPF_STACK 512
	81
30743837 DB	82	/* Macro to invoke filter function. */
30743837 DB	83	#define SK_RUN_FILTER(filter, ctx) (*filter->bpf_func)(ctx, filter->insnsi)
bd4cf0ed AS	84
	85	struct sock_filter_int {
	86	__u8 code; /* opcode */
	87	__u8 a_reg:4; /* dest register */
	88	__u8 x_reg:4; /* source register */
	89	__s16 off; /* signed offset */
	90	__s32 imm; /* signed immediate constant */
	91	};
	92
	93	#ifdef CONFIG_COMPAT
	94	/* A struct sock_filter is architecture independent. */
0c5fe1b4 WD	95	struct compat_sock_fprog {
0c5fe1b4 WD	96	u16 len;
bd4cf0ed	97	compat_uptr_t filter; /* struct sock_filter * */
0c5fe1b4 WD	98	};
	99	#endif
	100
a3ea269b DB	101	struct sock_fprog_kern {
	102	u16 len;
	103	struct sock_filter *filter;
	104	};
	105
792d4b5c HC	106	struct sk_buff;
792d4b5c HC	107	struct sock;
bd4cf0ed	108	struct seccomp_data;
792d4b5c	109
a3ea269b	110	struct sk_filter {
b715631f	111	atomic_t refcnt;
f8bbbfc3 DB	112	u32 jited:1, /* Is our filter JIT'ed? */
f8bbbfc3 DB	113	len:31; /* Number of filter blocks */
a3ea269b	114	struct sock_fprog_kern orig_prog; / Original BPF program */
d45ed4a4	115	struct rcu_head rcu;
0a14842f	116	unsigned int (bpf_func)(const struct sk_buff skb,
bd4cf0ed	117	const struct sock_filter_int *filter);
d45ed4a4	118	union {
bd4cf0ed AS	119	struct sock_filter insns[0];
bd4cf0ed AS	120	struct sock_filter_int insnsi[0];
d45ed4a4 AS	121	struct work_struct work;
d45ed4a4 AS	122	};
b715631f SH	123	};
b715631f SH	124
d45ed4a4	125	static inline unsigned int sk_filter_size(unsigned int proglen)
b715631f	126	{
d45ed4a4 AS	127	return max(sizeof(struct sk_filter),
d45ed4a4 AS	128	offsetof(struct sk_filter, insns[proglen]));
b715631f SH	129	}
b715631f SH	130
a3ea269b DB	131	#define sk_filter_proglen(fprog) \
	132	(fprog->len * sizeof(fprog->filter[0]))
	133
fbc907f0	134	int sk_filter(struct sock sk, struct sk_buff skb);
bd4cf0ed AS	135
	136	u32 sk_run_filter_int_seccomp(const struct seccomp_data *ctx,
	137	const struct sock_filter_int *insni);
	138	u32 sk_run_filter_int_skb(const struct sk_buff *ctx,
	139	const struct sock_filter_int *insni);
	140
	141	int sk_convert_filter(struct sock_filter *prog, int len,
	142	struct sock_filter_int new_prog, int new_len);
a3ea269b	143
fbc907f0 DB	144	int sk_unattached_filter_create(struct sk_filter **pfp,
	145	struct sock_fprog *fprog);
	146	void sk_unattached_filter_destroy(struct sk_filter *fp);
a3ea269b	147
fbc907f0 DB	148	int sk_attach_filter(struct sock_fprog fprog, struct sock sk);
fbc907f0 DB	149	int sk_detach_filter(struct sock *sk);
a3ea269b	150
fbc907f0 DB	151	int sk_chk_filter(struct sock_filter *filter, unsigned int flen);
	152	int sk_get_filter(struct sock sk, struct sock_filter __user filter,
	153	unsigned int len);
	154	void sk_decode_filter(struct sock_filter filt, struct sock_filter to);
	155
	156	void sk_filter_charge(struct sock sk, struct sk_filter fp);
	157	void sk_filter_uncharge(struct sock sk, struct sk_filter fp);
0a14842f ED	158
0a14842f ED	159	#ifdef CONFIG_BPF_JIT
20074f35	160	#include <stdarg.h>
a691ce7f CG	161	#include <linux/linkage.h>
	162	#include <linux/printk.h>
	163
fbc907f0 DB	164	void bpf_jit_compile(struct sk_filter *fp);
fbc907f0 DB	165	void bpf_jit_free(struct sk_filter *fp);
79617801 DB	166
	167	static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
	168	u32 pass, void *image)
	169	{
16495445	170	pr_err("flen=%u proglen=%u pass=%u image=%pK\n",
79617801 DB	171	flen, proglen, pass, image);
79617801 DB	172	if (image)
16495445	173	print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
79617801 DB	174	16, 1, image, proglen, false);
79617801 DB	175	}
0a14842f	176	#else
d45ed4a4	177	#include <linux/slab.h>
0a14842f ED	178	static inline void bpf_jit_compile(struct sk_filter *fp)
	179	{
	180	}
	181	static inline void bpf_jit_free(struct sk_filter *fp)
	182	{
d45ed4a4	183	kfree(fp);
0a14842f	184	}
0a14842f ED	185	#endif
0a14842f ED	186
ea02f941 MS	187	static inline int bpf_tell_extensions(void)
ea02f941 MS	188	{
37692299	189	return SKF_AD_MAX;
ea02f941 MS	190	}
ea02f941 MS	191
0a14842f ED	192	enum {
	193	BPF_S_RET_K = 1,
	194	BPF_S_RET_A,
	195	BPF_S_ALU_ADD_K,
	196	BPF_S_ALU_ADD_X,
	197	BPF_S_ALU_SUB_K,
	198	BPF_S_ALU_SUB_X,
	199	BPF_S_ALU_MUL_K,
	200	BPF_S_ALU_MUL_X,
	201	BPF_S_ALU_DIV_X,
b6069a95 ED	202	BPF_S_ALU_MOD_K,
b6069a95 ED	203	BPF_S_ALU_MOD_X,
0a14842f ED	204	BPF_S_ALU_AND_K,
	205	BPF_S_ALU_AND_X,
	206	BPF_S_ALU_OR_K,
	207	BPF_S_ALU_OR_X,
9e49e889 DB	208	BPF_S_ALU_XOR_K,
9e49e889 DB	209	BPF_S_ALU_XOR_X,
0a14842f ED	210	BPF_S_ALU_LSH_K,
	211	BPF_S_ALU_LSH_X,
	212	BPF_S_ALU_RSH_K,
	213	BPF_S_ALU_RSH_X,
	214	BPF_S_ALU_NEG,
	215	BPF_S_LD_W_ABS,
	216	BPF_S_LD_H_ABS,
	217	BPF_S_LD_B_ABS,
	218	BPF_S_LD_W_LEN,
	219	BPF_S_LD_W_IND,
	220	BPF_S_LD_H_IND,
	221	BPF_S_LD_B_IND,
	222	BPF_S_LD_IMM,
	223	BPF_S_LDX_W_LEN,
	224	BPF_S_LDX_B_MSH,
	225	BPF_S_LDX_IMM,
	226	BPF_S_MISC_TAX,
	227	BPF_S_MISC_TXA,
	228	BPF_S_ALU_DIV_K,
	229	BPF_S_LD_MEM,
	230	BPF_S_LDX_MEM,
	231	BPF_S_ST,
	232	BPF_S_STX,
	233	BPF_S_JMP_JA,
	234	BPF_S_JMP_JEQ_K,
	235	BPF_S_JMP_JEQ_X,
	236	BPF_S_JMP_JGE_K,
	237	BPF_S_JMP_JGE_X,
	238	BPF_S_JMP_JGT_K,
	239	BPF_S_JMP_JGT_X,
	240	BPF_S_JMP_JSET_K,
	241	BPF_S_JMP_JSET_X,
	242	/* Ancillary data */
	243	BPF_S_ANC_PROTOCOL,
	244	BPF_S_ANC_PKTTYPE,
	245	BPF_S_ANC_IFINDEX,
	246	BPF_S_ANC_NLATTR,
	247	BPF_S_ANC_NLATTR_NEST,
	248	BPF_S_ANC_MARK,
	249	BPF_S_ANC_QUEUE,
	250	BPF_S_ANC_HATYPE,
	251	BPF_S_ANC_RXHASH,
	252	BPF_S_ANC_CPU,
ffe06c17	253	BPF_S_ANC_ALU_XOR_X,
f3335031 ED	254	BPF_S_ANC_VLAN_TAG,
f3335031 ED	255	BPF_S_ANC_VLAN_TAG_PRESENT,
3e5289d5	256	BPF_S_ANC_PAY_OFFSET,
4cd3675e	257	BPF_S_ANC_RANDOM,
0a14842f ED	258	};
0a14842f ED	259
1da177e4	260	#endif /* __LINUX_FILTER_H__ */