236 lines
5.6 KiB
C
236 lines
5.6 KiB
C
/*
|
|
* Linux Socket Filter Data Structures
|
|
*/
|
|
|
|
#ifndef __LINUX_FILTER_H__
|
|
#define __LINUX_FILTER_H__
|
|
|
|
#include <linux/compiler.h>
|
|
#include <linux/types.h>
|
|
|
|
#ifdef __KERNEL__
|
|
#include <linux/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_RXHASH 32
|
|
#define SKF_AD_CPU 36
|
|
#define SKF_AD_MAX 40
|
|
#define SKF_NET_OFF (-0x100000)
|
|
#define SKF_LL_OFF (-0x200000)
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
struct sk_buff;
|
|
struct sock;
|
|
|
|
struct sk_filter
|
|
{
|
|
atomic_t refcnt;
|
|
unsigned int len; /* Number of filter blocks */
|
|
unsigned int (*bpf_func)(const struct sk_buff *skb,
|
|
const struct sock_filter *filter);
|
|
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);
|
|
}
|
|
|
|
extern int sk_filter(struct sock *sk, struct sk_buff *skb);
|
|
extern unsigned int sk_run_filter(const 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, unsigned int flen);
|
|
|
|
#ifdef CONFIG_BPF_JIT
|
|
extern void bpf_jit_compile(struct sk_filter *fp);
|
|
extern void bpf_jit_free(struct sk_filter *fp);
|
|
#define SK_RUN_FILTER(FILTER, SKB) (*FILTER->bpf_func)(SKB, FILTER->insns)
|
|
#else
|
|
static inline void bpf_jit_compile(struct sk_filter *fp)
|
|
{
|
|
}
|
|
static inline void bpf_jit_free(struct sk_filter *fp)
|
|
{
|
|
}
|
|
#define SK_RUN_FILTER(FILTER, SKB) sk_run_filter(SKB, FILTER->insns)
|
|
#endif
|
|
|
|
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_AND_K,
|
|
BPF_S_ALU_AND_X,
|
|
BPF_S_ALU_OR_K,
|
|
BPF_S_ALU_OR_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,
|
|
};
|
|
|
|
#endif /* __KERNEL__ */
|
|
|
|
#endif /* __LINUX_FILTER_H__ */
|