bpf_insn.h (6432B)
1/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */ 2/* eBPF instruction mini library */ 3#ifndef __BPF_INSN_H 4#define __BPF_INSN_H 5 6struct bpf_insn; 7 8/* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */ 9 10#define BPF_ALU64_REG(OP, DST, SRC) \ 11 ((struct bpf_insn) { \ 12 .code = BPF_ALU64 | BPF_OP(OP) | BPF_X, \ 13 .dst_reg = DST, \ 14 .src_reg = SRC, \ 15 .off = 0, \ 16 .imm = 0 }) 17 18#define BPF_ALU32_REG(OP, DST, SRC) \ 19 ((struct bpf_insn) { \ 20 .code = BPF_ALU | BPF_OP(OP) | BPF_X, \ 21 .dst_reg = DST, \ 22 .src_reg = SRC, \ 23 .off = 0, \ 24 .imm = 0 }) 25 26/* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */ 27 28#define BPF_ALU64_IMM(OP, DST, IMM) \ 29 ((struct bpf_insn) { \ 30 .code = BPF_ALU64 | BPF_OP(OP) | BPF_K, \ 31 .dst_reg = DST, \ 32 .src_reg = 0, \ 33 .off = 0, \ 34 .imm = IMM }) 35 36#define BPF_ALU32_IMM(OP, DST, IMM) \ 37 ((struct bpf_insn) { \ 38 .code = BPF_ALU | BPF_OP(OP) | BPF_K, \ 39 .dst_reg = DST, \ 40 .src_reg = 0, \ 41 .off = 0, \ 42 .imm = IMM }) 43 44/* Short form of mov, dst_reg = src_reg */ 45 46#define BPF_MOV64_REG(DST, SRC) \ 47 ((struct bpf_insn) { \ 48 .code = BPF_ALU64 | BPF_MOV | BPF_X, \ 49 .dst_reg = DST, \ 50 .src_reg = SRC, \ 51 .off = 0, \ 52 .imm = 0 }) 53 54#define BPF_MOV32_REG(DST, SRC) \ 55 ((struct bpf_insn) { \ 56 .code = BPF_ALU | BPF_MOV | BPF_X, \ 57 .dst_reg = DST, \ 58 .src_reg = SRC, \ 59 .off = 0, \ 60 .imm = 0 }) 61 62/* Short form of mov, dst_reg = imm32 */ 63 64#define BPF_MOV64_IMM(DST, IMM) \ 65 ((struct bpf_insn) { \ 66 .code = BPF_ALU64 | BPF_MOV | BPF_K, \ 67 .dst_reg = DST, \ 68 .src_reg = 0, \ 69 .off = 0, \ 70 .imm = IMM }) 71 72#define BPF_MOV32_IMM(DST, IMM) \ 73 ((struct bpf_insn) { \ 74 .code = BPF_ALU | BPF_MOV | BPF_K, \ 75 .dst_reg = DST, \ 76 .src_reg = 0, \ 77 .off = 0, \ 78 .imm = IMM }) 79 80/* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */ 81#define BPF_LD_IMM64(DST, IMM) \ 82 BPF_LD_IMM64_RAW(DST, 0, IMM) 83 84#define BPF_LD_IMM64_RAW(DST, SRC, IMM) \ 85 ((struct bpf_insn) { \ 86 .code = BPF_LD | BPF_DW | BPF_IMM, \ 87 .dst_reg = DST, \ 88 .src_reg = SRC, \ 89 .off = 0, \ 90 .imm = (__u32) (IMM) }), \ 91 ((struct bpf_insn) { \ 92 .code = 0, /* zero is reserved opcode */ \ 93 .dst_reg = 0, \ 94 .src_reg = 0, \ 95 .off = 0, \ 96 .imm = ((__u64) (IMM)) >> 32 }) 97 98#ifndef BPF_PSEUDO_MAP_FD 99# define BPF_PSEUDO_MAP_FD 1 100#endif 101 102/* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */ 103#define BPF_LD_MAP_FD(DST, MAP_FD) \ 104 BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD) 105 106 107/* Direct packet access, R0 = *(uint *) (skb->data + imm32) */ 108 109#define BPF_LD_ABS(SIZE, IMM) \ 110 ((struct bpf_insn) { \ 111 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS, \ 112 .dst_reg = 0, \ 113 .src_reg = 0, \ 114 .off = 0, \ 115 .imm = IMM }) 116 117/* Memory load, dst_reg = *(uint *) (src_reg + off16) */ 118 119#define BPF_LDX_MEM(SIZE, DST, SRC, OFF) \ 120 ((struct bpf_insn) { \ 121 .code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM, \ 122 .dst_reg = DST, \ 123 .src_reg = SRC, \ 124 .off = OFF, \ 125 .imm = 0 }) 126 127/* Memory store, *(uint *) (dst_reg + off16) = src_reg */ 128 129#define BPF_STX_MEM(SIZE, DST, SRC, OFF) \ 130 ((struct bpf_insn) { \ 131 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM, \ 132 .dst_reg = DST, \ 133 .src_reg = SRC, \ 134 .off = OFF, \ 135 .imm = 0 }) 136 137/* 138 * Atomic operations: 139 * 140 * BPF_ADD *(uint *) (dst_reg + off16) += src_reg 141 * BPF_AND *(uint *) (dst_reg + off16) &= src_reg 142 * BPF_OR *(uint *) (dst_reg + off16) |= src_reg 143 * BPF_XOR *(uint *) (dst_reg + off16) ^= src_reg 144 * BPF_ADD | BPF_FETCH src_reg = atomic_fetch_add(dst_reg + off16, src_reg); 145 * BPF_AND | BPF_FETCH src_reg = atomic_fetch_and(dst_reg + off16, src_reg); 146 * BPF_OR | BPF_FETCH src_reg = atomic_fetch_or(dst_reg + off16, src_reg); 147 * BPF_XOR | BPF_FETCH src_reg = atomic_fetch_xor(dst_reg + off16, src_reg); 148 * BPF_XCHG src_reg = atomic_xchg(dst_reg + off16, src_reg) 149 * BPF_CMPXCHG r0 = atomic_cmpxchg(dst_reg + off16, r0, src_reg) 150 */ 151 152#define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF) \ 153 ((struct bpf_insn) { \ 154 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC, \ 155 .dst_reg = DST, \ 156 .src_reg = SRC, \ 157 .off = OFF, \ 158 .imm = OP }) 159 160/* Legacy alias */ 161#define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF) 162 163/* Memory store, *(uint *) (dst_reg + off16) = imm32 */ 164 165#define BPF_ST_MEM(SIZE, DST, OFF, IMM) \ 166 ((struct bpf_insn) { \ 167 .code = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM, \ 168 .dst_reg = DST, \ 169 .src_reg = 0, \ 170 .off = OFF, \ 171 .imm = IMM }) 172 173/* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */ 174 175#define BPF_JMP_REG(OP, DST, SRC, OFF) \ 176 ((struct bpf_insn) { \ 177 .code = BPF_JMP | BPF_OP(OP) | BPF_X, \ 178 .dst_reg = DST, \ 179 .src_reg = SRC, \ 180 .off = OFF, \ 181 .imm = 0 }) 182 183/* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */ 184 185#define BPF_JMP32_REG(OP, DST, SRC, OFF) \ 186 ((struct bpf_insn) { \ 187 .code = BPF_JMP32 | BPF_OP(OP) | BPF_X, \ 188 .dst_reg = DST, \ 189 .src_reg = SRC, \ 190 .off = OFF, \ 191 .imm = 0 }) 192 193/* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */ 194 195#define BPF_JMP_IMM(OP, DST, IMM, OFF) \ 196 ((struct bpf_insn) { \ 197 .code = BPF_JMP | BPF_OP(OP) | BPF_K, \ 198 .dst_reg = DST, \ 199 .src_reg = 0, \ 200 .off = OFF, \ 201 .imm = IMM }) 202 203/* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */ 204 205#define BPF_JMP32_IMM(OP, DST, IMM, OFF) \ 206 ((struct bpf_insn) { \ 207 .code = BPF_JMP32 | BPF_OP(OP) | BPF_K, \ 208 .dst_reg = DST, \ 209 .src_reg = 0, \ 210 .off = OFF, \ 211 .imm = IMM }) 212 213/* Raw code statement block */ 214 215#define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM) \ 216 ((struct bpf_insn) { \ 217 .code = CODE, \ 218 .dst_reg = DST, \ 219 .src_reg = SRC, \ 220 .off = OFF, \ 221 .imm = IMM }) 222 223/* Program exit */ 224 225#define BPF_EXIT_INSN() \ 226 ((struct bpf_insn) { \ 227 .code = BPF_JMP | BPF_EXIT, \ 228 .dst_reg = 0, \ 229 .src_reg = 0, \ 230 .off = 0, \ 231 .imm = 0 }) 232 233#endif