LXR linux/include/uapi/linux/filter.h

   1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
   2/*
   3 * Linux Socket Filter Data Structures
   4 */
   5
   6#ifndef _UAPI__LINUX_FILTER_H__
   7#define _UAPI__LINUX_FILTER_H__
   8
   9#include <linux/compiler.h>
  10#include <linux/types.h>
  11#include <linux/bpf_common.h>
  12
  13/*
  14 * Current version of the filter code architecture.
  15 */
  16#define BPF_MAJOR_VERSION 1
  17#define BPF_MINOR_VERSION 1
  18
  19/*
  20 *      Try and keep these values and structures similar to BSD, especially
  21 *      the BPF code definitions which need to match so you can share filters
  22 */
  23 
  24struct sock_filter {    /* Filter block */
  25        __u16   code;   /* Actual filter code */
  26        __u8    jt;     /* Jump true */
  27        __u8    jf;     /* Jump false */
  28        __u32   k;      /* Generic multiuse field */
  29};
  30
  31struct sock_fprog {     /* Required for SO_ATTACH_FILTER. */
  32        unsigned short          len;    /* Number of filter blocks */
  33        struct sock_filter __user *filter;
  34};
  35
  36/* ret - BPF_K and BPF_X also apply */
  37#define BPF_RVAL(code)  ((code) & 0x18)
  38#define         BPF_A           0x10
  39
  40/* misc */
  41#define BPF_MISCOP(code) ((code) & 0xf8)
  42#define         BPF_TAX         0x00
  43#define         BPF_TXA         0x80
  44
  45/*
  46 * Macros for filter block array initializers.
  47 */
  48#ifndef BPF_STMT
  49#define BPF_STMT(code, k) { (unsigned short)(code), 0, 0, k }
  50#endif
  51#ifndef BPF_JUMP
  52#define BPF_JUMP(code, k, jt, jf) { (unsigned short)(code), jt, jf, k }
  53#endif
  54
  55/*
  56 * Number of scratch memory words for: BPF_ST and BPF_STX
  57 */
  58#define BPF_MEMWORDS 16
  59
  60/* RATIONALE. Negative offsets are invalid in BPF.
  61   We use them to reference ancillary data.
  62   Unlike introduction new instructions, it does not break
  63   existing compilers/optimizers.
  64 */
  65#define SKF_AD_OFF    (-0x1000)
  66#define SKF_AD_PROTOCOL 0
  67#define SKF_AD_PKTTYPE  4
  68#define SKF_AD_IFINDEX  8
  69#define SKF_AD_NLATTR   12
  70#define SKF_AD_NLATTR_NEST      16
  71#define SKF_AD_MARK     20
  72#define SKF_AD_QUEUE    24
  73#define SKF_AD_HATYPE   28
  74#define SKF_AD_RXHASH   32
  75#define SKF_AD_CPU      36
  76#define SKF_AD_ALU_XOR_X        40
  77#define SKF_AD_VLAN_TAG 44
  78#define SKF_AD_VLAN_TAG_PRESENT 48
  79#define SKF_AD_PAY_OFFSET       52
  80#define SKF_AD_RANDOM   56
  81#define SKF_AD_VLAN_TPID        60
  82#define SKF_AD_MAX      64
  83
  84#define SKF_NET_OFF     (-0x100000)
  85#define SKF_LL_OFF      (-0x200000)
  86
  87#define BPF_NET_OFF     SKF_NET_OFF
  88#define BPF_LL_OFF      SKF_LL_OFF
  89
  90#endif /* _UAPI__LINUX_FILTER_H__ */
  91