root/include/uapi/linux/bpf.h

/* [<][>][^][v][top][bottom][index][help] */

INCLUDED FROM


/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 */
#ifndef _UAPI__LINUX_BPF_H__
#define _UAPI__LINUX_BPF_H__

#include <linux/types.h>
#include <linux/bpf_common.h>

/* 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 */

/* 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

struct bpf_insn {
        __u8    code;           /* opcode */
        __u8    dst_reg:4;      /* dest register */
        __u8    src_reg:4;      /* source register */
        __s16   off;            /* signed offset */
        __s32   imm;            /* signed immediate constant */
};

/* BPF syscall commands */
enum bpf_cmd {
        /* create a map with given type and attributes
         * fd = bpf(BPF_MAP_CREATE, union bpf_attr *, u32 size)
         * returns fd or negative error
         * map is deleted when fd is closed
         */
        BPF_MAP_CREATE,

        /* lookup key in a given map
         * err = bpf(BPF_MAP_LOOKUP_ELEM, union bpf_attr *attr, u32 size)
         * Using attr->map_fd, attr->key, attr->value
         * returns zero and stores found elem into value
         * or negative error
         */
        BPF_MAP_LOOKUP_ELEM,

        /* create or update key/value pair in a given map
         * err = bpf(BPF_MAP_UPDATE_ELEM, union bpf_attr *attr, u32 size)
         * Using attr->map_fd, attr->key, attr->value
         * returns zero or negative error
         */
        BPF_MAP_UPDATE_ELEM,

        /* find and delete elem by key in a given map
         * err = bpf(BPF_MAP_DELETE_ELEM, union bpf_attr *attr, u32 size)
         * Using attr->map_fd, attr->key
         * returns zero or negative error
         */
        BPF_MAP_DELETE_ELEM,

        /* lookup key in a given map and return next key
         * err = bpf(BPF_MAP_GET_NEXT_KEY, union bpf_attr *attr, u32 size)
         * Using attr->map_fd, attr->key, attr->next_key
         * returns zero and stores next key or negative error
         */
        BPF_MAP_GET_NEXT_KEY,

        /* verify and load eBPF program
         * prog_fd = bpf(BPF_PROG_LOAD, union bpf_attr *attr, u32 size)
         * Using attr->prog_type, attr->insns, attr->license
         * returns fd or negative error
         */
        BPF_PROG_LOAD,
};

enum bpf_map_type {
        BPF_MAP_TYPE_UNSPEC,
};

enum bpf_prog_type {
        BPF_PROG_TYPE_UNSPEC,
};

union bpf_attr {
        struct { /* anonymous struct used by BPF_MAP_CREATE command */
                __u32   map_type;       /* one of enum bpf_map_type */
                __u32   key_size;       /* size of key in bytes */
                __u32   value_size;     /* size of value in bytes */
                __u32   max_entries;    /* max number of entries in a map */
        };

        struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */
                __u32           map_fd;
                __aligned_u64   key;
                union {
                        __aligned_u64 value;
                        __aligned_u64 next_key;
                };
        };

        struct { /* anonymous struct used by BPF_PROG_LOAD command */
                __u32           prog_type;      /* one of enum bpf_prog_type */
                __u32           insn_cnt;
                __aligned_u64   insns;
                __aligned_u64   license;
                __u32           log_level;      /* verbosity level of verifier */
                __u32           log_size;       /* size of user buffer */
                __aligned_u64   log_buf;        /* user supplied buffer */
        };
} __attribute__((aligned(8)));

/* integer value in 'imm' field of BPF_CALL instruction selects which helper
 * function eBPF program intends to call
 */
enum bpf_func_id {
        BPF_FUNC_unspec,
        __BPF_FUNC_MAX_ID,
};

#endif /* _UAPI__LINUX_BPF_H__ */

/* [<][>][^][v][top][bottom][index][help] */