LXR linux/include/uapi/linux/bpf.h

   1/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
   2 *
   3 * This program is free software; you can redistribute it and/or
   4 * modify it under the terms of version 2 of the GNU General Public
   5 * License as published by the Free Software Foundation.
   6 */
   7#ifndef _UAPI__LINUX_BPF_H__
   8#define _UAPI__LINUX_BPF_H__
   9
  10#include <linux/types.h>
  11#include <linux/bpf_common.h>
  12
  13/* Extended instruction set based on top of classic BPF */
  14
  15/* instruction classes */
  16#define BPF_ALU64       0x07    /* alu mode in double word width */
  17
  18/* ld/ldx fields */
  19#define BPF_DW          0x18    /* double word */
  20#define BPF_XADD        0xc0    /* exclusive add */
  21
  22/* alu/jmp fields */
  23#define BPF_MOV         0xb0    /* mov reg to reg */
  24#define BPF_ARSH        0xc0    /* sign extending arithmetic shift right */
  25
  26/* change endianness of a register */
  27#define BPF_END         0xd0    /* flags for endianness conversion: */
  28#define BPF_TO_LE       0x00    /* convert to little-endian */
  29#define BPF_TO_BE       0x08    /* convert to big-endian */
  30#define BPF_FROM_LE     BPF_TO_LE
  31#define BPF_FROM_BE     BPF_TO_BE
  32
  33#define BPF_JNE         0x50    /* jump != */
  34#define BPF_JSGT        0x60    /* SGT is signed '>', GT in x86 */
  35#define BPF_JSGE        0x70    /* SGE is signed '>=', GE in x86 */
  36#define BPF_CALL        0x80    /* function call */
  37#define BPF_EXIT        0x90    /* function return */
  38
  39/* Register numbers */
  40enum {
  41        BPF_REG_0 = 0,
  42        BPF_REG_1,
  43        BPF_REG_2,
  44        BPF_REG_3,
  45        BPF_REG_4,
  46        BPF_REG_5,
  47        BPF_REG_6,
  48        BPF_REG_7,
  49        BPF_REG_8,
  50        BPF_REG_9,
  51        BPF_REG_10,
  52        __MAX_BPF_REG,
  53};
  54
  55/* BPF has 10 general purpose 64-bit registers and stack frame. */
  56#define MAX_BPF_REG     __MAX_BPF_REG
  57
  58struct bpf_insn {
  59        __u8    code;           /* opcode */
  60        __u8    dst_reg:4;      /* dest register */
  61        __u8    src_reg:4;      /* source register */
  62        __s16   off;            /* signed offset */
  63        __s32   imm;            /* signed immediate constant */
  64};
  65
  66/* BPF syscall commands */
  67enum bpf_cmd {
  68        /* create a map with given type and attributes
  69         * fd = bpf(BPF_MAP_CREATE, union bpf_attr *, u32 size)
  70         * returns fd or negative error
  71         * map is deleted when fd is closed
  72         */
  73        BPF_MAP_CREATE,
  74
  75        /* lookup key in a given map
  76         * err = bpf(BPF_MAP_LOOKUP_ELEM, union bpf_attr *attr, u32 size)
  77         * Using attr->map_fd, attr->key, attr->value
  78         * returns zero and stores found elem into value
  79         * or negative error
  80         */
  81        BPF_MAP_LOOKUP_ELEM,
  82
  83        /* create or update key/value pair in a given map
  84         * err = bpf(BPF_MAP_UPDATE_ELEM, union bpf_attr *attr, u32 size)
  85         * Using attr->map_fd, attr->key, attr->value
  86         * returns zero or negative error
  87         */
  88        BPF_MAP_UPDATE_ELEM,
  89
  90        /* find and delete elem by key in a given map
  91         * err = bpf(BPF_MAP_DELETE_ELEM, union bpf_attr *attr, u32 size)
  92         * Using attr->map_fd, attr->key
  93         * returns zero or negative error
  94         */
  95        BPF_MAP_DELETE_ELEM,
  96
  97        /* lookup key in a given map and return next key
  98         * err = bpf(BPF_MAP_GET_NEXT_KEY, union bpf_attr *attr, u32 size)
  99         * Using attr->map_fd, attr->key, attr->next_key
 100         * returns zero and stores next key or negative error
 101         */
 102        BPF_MAP_GET_NEXT_KEY,
 103
 104        /* verify and load eBPF program
 105         * prog_fd = bpf(BPF_PROG_LOAD, union bpf_attr *attr, u32 size)
 106         * Using attr->prog_type, attr->insns, attr->license
 107         * returns fd or negative error
 108         */
 109        BPF_PROG_LOAD,
 110};
 111
 112enum bpf_map_type {
 113        BPF_MAP_TYPE_UNSPEC,
 114};
 115
 116enum bpf_prog_type {
 117        BPF_PROG_TYPE_UNSPEC,
 118};
 119
 120union bpf_attr {
 121        struct { /* anonymous struct used by BPF_MAP_CREATE command */
 122                __u32   map_type;       /* one of enum bpf_map_type */
 123                __u32   key_size;       /* size of key in bytes */
 124                __u32   value_size;     /* size of value in bytes */
 125                __u32   max_entries;    /* max number of entries in a map */
 126        };
 127
 128        struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */
 129                __u32           map_fd;
 130                __aligned_u64   key;
 131                union {
 132                        __aligned_u64 value;
 133                        __aligned_u64 next_key;
 134                };
 135        };
 136
 137        struct { /* anonymous struct used by BPF_PROG_LOAD command */
 138                __u32           prog_type;      /* one of enum bpf_prog_type */
 139                __u32           insn_cnt;
 140                __aligned_u64   insns;
 141                __aligned_u64   license;
 142                __u32           log_level;      /* verbosity level of verifier */
 143                __u32           log_size;       /* size of user buffer */
 144                __aligned_u64   log_buf;        /* user supplied buffer */
 145        };
 146} __attribute__((aligned(8)));
 147
 148/* integer value in 'imm' field of BPF_CALL instruction selects which helper
 149 * function eBPF program intends to call
 150 */
 151enum bpf_func_id {
 152        BPF_FUNC_unspec,
 153        __BPF_FUNC_MAX_ID,
 154};
 155
 156#endif /* _UAPI__LINUX_BPF_H__ */
 157