1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Linux Socket Filter Data Structures 4 */ 5 #ifndef __TOOLS_LINUX_FILTER_H 6 #define __TOOLS_LINUX_FILTER_H 7 8 #include <linux/bpf.h> 9 10 /* ArgX, context and stack frame pointer register positions. Note, 11 * Arg1, Arg2, Arg3, etc are used as argument mappings of function 12 * calls in BPF_CALL instruction. 13 */ 14 #define BPF_REG_ARG1 BPF_REG_1 15 #define BPF_REG_ARG2 BPF_REG_2 16 #define BPF_REG_ARG3 BPF_REG_3 17 #define BPF_REG_ARG4 BPF_REG_4 18 #define BPF_REG_ARG5 BPF_REG_5 19 #define BPF_REG_CTX BPF_REG_6 20 #define BPF_REG_FP BPF_REG_10 21 22 /* Additional register mappings for converted user programs. */ 23 #define BPF_REG_A BPF_REG_0 24 #define BPF_REG_X BPF_REG_7 25 #define BPF_REG_TMP BPF_REG_8 26 27 /* BPF program can access up to 512 bytes of stack space. */ 28 #define MAX_BPF_STACK 512 29 30 /* Helper macros for filter block array initializers. */ 31 32 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */ 33 34 #define BPF_ALU64_REG(OP, DST, SRC) \ 35 ((struct bpf_insn) { \ 36 .code = BPF_ALU64 | BPF_OP(OP) | BPF_X, \ 37 .dst_reg = DST, \ 38 .src_reg = SRC, \ 39 .off = 0, \ 40 .imm = 0 }) 41 42 #define BPF_ALU32_REG(OP, DST, SRC) \ 43 ((struct bpf_insn) { \ 44 .code = BPF_ALU | BPF_OP(OP) | BPF_X, \ 45 .dst_reg = DST, \ 46 .src_reg = SRC, \ 47 .off = 0, \ 48 .imm = 0 }) 49 50 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */ 51 52 #define BPF_ALU64_IMM(OP, DST, IMM) \ 53 ((struct bpf_insn) { \ 54 .code = BPF_ALU64 | BPF_OP(OP) | BPF_K, \ 55 .dst_reg = DST, \ 56 .src_reg = 0, \ 57 .off = 0, \ 58 .imm = IMM }) 59 60 #define BPF_ALU32_IMM(OP, DST, IMM) \ 61 ((struct bpf_insn) { \ 62 .code = BPF_ALU | BPF_OP(OP) | BPF_K, \ 63 .dst_reg = DST, \ 64 .src_reg = 0, \ 65 .off = 0, \ 66 .imm = IMM }) 67 68 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */ 69 70 #define BPF_ENDIAN(TYPE, DST, LEN) \ 71 ((struct bpf_insn) { \ 72 .code = BPF_ALU | BPF_END | BPF_SRC(TYPE), \ 73 .dst_reg = DST, \ 74 .src_reg = 0, \ 75 .off = 0, \ 76 .imm = LEN }) 77 78 /* Short form of mov, dst_reg = src_reg */ 79 80 #define BPF_MOV64_REG(DST, SRC) \ 81 ((struct bpf_insn) { \ 82 .code = BPF_ALU64 | BPF_MOV | BPF_X, \ 83 .dst_reg = DST, \ 84 .src_reg = SRC, \ 85 .off = 0, \ 86 .imm = 0 }) 87 88 #define BPF_MOV32_REG(DST, SRC) \ 89 ((struct bpf_insn) { \ 90 .code = BPF_ALU | BPF_MOV | BPF_X, \ 91 .dst_reg = DST, \ 92 .src_reg = SRC, \ 93 .off = 0, \ 94 .imm = 0 }) 95 96 /* Short form of mov, dst_reg = imm32 */ 97 98 #define BPF_MOV64_IMM(DST, IMM) \ 99 ((struct bpf_insn) { \ 100 .code = BPF_ALU64 | BPF_MOV | BPF_K, \ 101 .dst_reg = DST, \ 102 .src_reg = 0, \ 103 .off = 0, \ 104 .imm = IMM }) 105 106 #define BPF_MOV32_IMM(DST, IMM) \ 107 ((struct bpf_insn) { \ 108 .code = BPF_ALU | BPF_MOV | BPF_K, \ 109 .dst_reg = DST, \ 110 .src_reg = 0, \ 111 .off = 0, \ 112 .imm = IMM }) 113 114 /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */ 115 116 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM) \ 117 ((struct bpf_insn) { \ 118 .code = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE), \ 119 .dst_reg = DST, \ 120 .src_reg = SRC, \ 121 .off = 0, \ 122 .imm = IMM }) 123 124 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM) \ 125 ((struct bpf_insn) { \ 126 .code = BPF_ALU | BPF_MOV | BPF_SRC(TYPE), \ 127 .dst_reg = DST, \ 128 .src_reg = SRC, \ 129 .off = 0, \ 130 .imm = IMM }) 131 132 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */ 133 134 #define BPF_LD_ABS(SIZE, IMM) \ 135 ((struct bpf_insn) { \ 136 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS, \ 137 .dst_reg = 0, \ 138 .src_reg = 0, \ 139 .off = 0, \ 140 .imm = IMM }) 141 142 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */ 143 144 #define BPF_LD_IND(SIZE, SRC, IMM) \ 145 ((struct bpf_insn) { \ 146 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_IND, \ 147 .dst_reg = 0, \ 148 .src_reg = SRC, \ 149 .off = 0, \ 150 .imm = IMM }) 151 152 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */ 153 154 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF) \ 155 ((struct bpf_insn) { \ 156 .code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM, \ 157 .dst_reg = DST, \ 158 .src_reg = SRC, \ 159 .off = OFF, \ 160 .imm = 0 }) 161 162 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */ 163 164 #define BPF_STX_MEM(SIZE, DST, SRC, OFF) \ 165 ((struct bpf_insn) { \ 166 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM, \ 167 .dst_reg = DST, \ 168 .src_reg = SRC, \ 169 .off = OFF, \ 170 .imm = 0 }) 171 172 /* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */ 173 174 #define BPF_STX_XADD(SIZE, DST, SRC, OFF) \ 175 ((struct bpf_insn) { \ 176 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD, \ 177 .dst_reg = DST, \ 178 .src_reg = SRC, \ 179 .off = OFF, \ 180 .imm = 0 }) 181 182 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */ 183 184 #define BPF_ST_MEM(SIZE, DST, OFF, IMM) \ 185 ((struct bpf_insn) { \ 186 .code = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM, \ 187 .dst_reg = DST, \ 188 .src_reg = 0, \ 189 .off = OFF, \ 190 .imm = IMM }) 191 192 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */ 193 194 #define BPF_JMP_REG(OP, DST, SRC, OFF) \ 195 ((struct bpf_insn) { \ 196 .code = BPF_JMP | BPF_OP(OP) | BPF_X, \ 197 .dst_reg = DST, \ 198 .src_reg = SRC, \ 199 .off = OFF, \ 200 .imm = 0 }) 201 202 /* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */ 203 204 #define BPF_JMP32_REG(OP, DST, SRC, OFF) \ 205 ((struct bpf_insn) { \ 206 .code = BPF_JMP32 | BPF_OP(OP) | BPF_X, \ 207 .dst_reg = DST, \ 208 .src_reg = SRC, \ 209 .off = OFF, \ 210 .imm = 0 }) 211 212 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */ 213 214 #define BPF_JMP_IMM(OP, DST, IMM, OFF) \ 215 ((struct bpf_insn) { \ 216 .code = BPF_JMP | BPF_OP(OP) | BPF_K, \ 217 .dst_reg = DST, \ 218 .src_reg = 0, \ 219 .off = OFF, \ 220 .imm = IMM }) 221 222 /* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */ 223 224 #define BPF_JMP32_IMM(OP, DST, IMM, OFF) \ 225 ((struct bpf_insn) { \ 226 .code = BPF_JMP32 | BPF_OP(OP) | BPF_K, \ 227 .dst_reg = DST, \ 228 .src_reg = 0, \ 229 .off = OFF, \ 230 .imm = IMM }) 231 232 /* Unconditional jumps, goto pc + off16 */ 233 234 #define BPF_JMP_A(OFF) \ 235 ((struct bpf_insn) { \ 236 .code = BPF_JMP | BPF_JA, \ 237 .dst_reg = 0, \ 238 .src_reg = 0, \ 239 .off = OFF, \ 240 .imm = 0 }) 241 242 /* Function call */ 243 244 #define BPF_EMIT_CALL(FUNC) \ 245 ((struct bpf_insn) { \ 246 .code = BPF_JMP | BPF_CALL, \ 247 .dst_reg = 0, \ 248 .src_reg = 0, \ 249 .off = 0, \ 250 .imm = ((FUNC) - BPF_FUNC_unspec) }) 251 252 /* Raw code statement block */ 253 254 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM) \ 255 ((struct bpf_insn) { \ 256 .code = CODE, \ 257 .dst_reg = DST, \ 258 .src_reg = SRC, \ 259 .off = OFF, \ 260 .imm = IMM }) 261 262 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */ 263 264 #define BPF_LD_IMM64(DST, IMM) \ 265 BPF_LD_IMM64_RAW(DST, 0, IMM) 266 267 #define BPF_LD_IMM64_RAW(DST, SRC, IMM) \ 268 ((struct bpf_insn) { \ 269 .code = BPF_LD | BPF_DW | BPF_IMM, \ 270 .dst_reg = DST, \ 271 .src_reg = SRC, \ 272 .off = 0, \ 273 .imm = (__u32) (IMM) }), \ 274 ((struct bpf_insn) { \ 275 .code = 0, /* zero is reserved opcode */ \ 276 .dst_reg = 0, \ 277 .src_reg = 0, \ 278 .off = 0, \ 279 .imm = ((__u64) (IMM)) >> 32 }) 280 281 #define BPF_LD_IMM64_RAW_FULL(DST, SRC, OFF1, OFF2, IMM1, IMM2) \ 282 ((struct bpf_insn) { \ 283 .code = BPF_LD | BPF_DW | BPF_IMM, \ 284 .dst_reg = DST, \ 285 .src_reg = SRC, \ 286 .off = OFF1, \ 287 .imm = IMM1 }), \ 288 ((struct bpf_insn) { \ 289 .code = 0, /* zero is reserved opcode */ \ 290 .dst_reg = 0, \ 291 .src_reg = 0, \ 292 .off = OFF2, \ 293 .imm = IMM2 }) 294 295 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */ 296 297 #define BPF_LD_MAP_FD(DST, MAP_FD) \ 298 BPF_LD_IMM64_RAW_FULL(DST, BPF_PSEUDO_MAP_FD, 0, 0, \ 299 MAP_FD, 0) 300 301 #define BPF_LD_MAP_VALUE(DST, MAP_FD, VALUE_OFF) \ 302 BPF_LD_IMM64_RAW_FULL(DST, BPF_PSEUDO_MAP_VALUE, 0, 0, \ 303 MAP_FD, VALUE_OFF) 304 305 /* Relative call */ 306 307 #define BPF_CALL_REL(TGT) \ 308 ((struct bpf_insn) { \ 309 .code = BPF_JMP | BPF_CALL, \ 310 .dst_reg = 0, \ 311 .src_reg = BPF_PSEUDO_CALL, \ 312 .off = 0, \ 313 .imm = TGT }) 314 315 /* Program exit */ 316 317 #define BPF_EXIT_INSN() \ 318 ((struct bpf_insn) { \ 319 .code = BPF_JMP | BPF_EXIT, \ 320 .dst_reg = 0, \ 321 .src_reg = 0, \ 322 .off = 0, \ 323 .imm = 0 }) 324 325 #endif /* __TOOLS_LINUX_FILTER_H */ 326