1/* 2 * Linux Socket Filter Data Structures 3 */ 4 5#ifndef __LINUX_FILTER_H__ 6#define __LINUX_FILTER_H__ 7 8#include <linux/types.h> 9 10 11/* 12 * Current version of the filter code architecture. 13 */ 14#define BPF_MAJOR_VERSION 1 15#define BPF_MINOR_VERSION 1 16 17/* 18 * Try and keep these values and structures similar to BSD, especially 19 * the BPF code definitions which need to match so you can share filters 20 */ 21 22struct sock_filter /* Filter block */ 23{ 24 __u16 code; /* Actual filter code */ 25 __u8 jt; /* Jump true */ 26 __u8 jf; /* Jump false */ 27 __u32 k; /* Generic multiuse field */ 28}; 29 30struct sock_fprog /* Required for SO_ATTACH_FILTER. */ 31{ 32 unsigned short len; /* Number of filter blocks */ 33 struct sock_filter *filter; 34}; 35 36 37/* 38 * Instruction classes 39 */ 40 41#define BPF_CLASS(code) ((code) & 0x07) 42#define BPF_LD 0x00 43#define BPF_LDX 0x01 44#define BPF_ST 0x02 45#define BPF_STX 0x03 46#define BPF_ALU 0x04 47#define BPF_JMP 0x05 48#define BPF_RET 0x06 49#define BPF_MISC 0x07 50 51/* ld/ldx fields */ 52#define BPF_SIZE(code) ((code) & 0x18) 53#define BPF_W 0x00 54#define BPF_H 0x08 55#define BPF_B 0x10 56#define BPF_MODE(code) ((code) & 0xe0) 57#define BPF_IMM 0x00 58#define BPF_ABS 0x20 59#define BPF_IND 0x40 60#define BPF_MEM 0x60 61#define BPF_LEN 0x80 62#define BPF_MSH 0xa0 63 64/* alu/jmp fields */ 65#define BPF_OP(code) ((code) & 0xf0) 66#define BPF_ADD 0x00 67#define BPF_SUB 0x10 68#define BPF_MUL 0x20 69#define BPF_DIV 0x30 70#define BPF_OR 0x40 71#define BPF_AND 0x50 72#define BPF_LSH 0x60 73#define BPF_RSH 0x70 74#define BPF_NEG 0x80 75#define BPF_JA 0x00 76#define BPF_JEQ 0x10 77#define BPF_JGT 0x20 78#define BPF_JGE 0x30 79#define BPF_JSET 0x40 80#define BPF_SRC(code) ((code) & 0x08) 81#define BPF_K 0x00 82#define BPF_X 0x08 83 84/* ret - BPF_K and BPF_X also apply */ 85#define BPF_RVAL(code) ((code) & 0x18) 86#define BPF_A 0x10 87 88/* misc */ 89#define BPF_MISCOP(code) ((code) & 0xf8) 90#define BPF_TAX 0x00 91#define BPF_TXA 0x80 92 93#ifndef BPF_MAXINSNS 94#define BPF_MAXINSNS 4096 95#endif 96 97/* 98 * Macros for filter block array initializers. 99 */ 100#ifndef BPF_STMT 101#define BPF_STMT(code, k) { (unsigned short)(code), 0, 0, k } 102#endif 103#ifndef BPF_JUMP 104#define BPF_JUMP(code, k, jt, jf) { (unsigned short)(code), jt, jf, k } 105#endif 106 107/* 108 * Number of scratch memory words for: BPF_ST and BPF_STX 109 */ 110#define BPF_MEMWORDS 16 111 112/* RATIONALE. Negative offsets are invalid in BPF. 113 We use them to reference ancillary data. 114 Unlike introduction new instructions, it does not break 115 existing compilers/optimizers. 116 */ 117#define SKF_AD_OFF (-0x1000) 118#define SKF_AD_PROTOCOL 0 119#define SKF_AD_PKTTYPE 4 120#define SKF_AD_IFINDEX 8 121#define SKF_AD_MAX 12 122#define SKF_NET_OFF (-0x100000) 123#define SKF_LL_OFF (-0x200000) 124 125 126#endif /* __LINUX_FILTER_H__ */ 127