tools/include/linux/filter.h

   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 /*
 173  * Atomic operations:
 174  *
 175  *   BPF_ADD                  *(uint *) (dst_reg + off16) += src_reg
 176  *   BPF_AND                  *(uint *) (dst_reg + off16) &= src_reg
 177  *   BPF_OR                   *(uint *) (dst_reg + off16) |= src_reg
 178  *   BPF_XOR                  *(uint *) (dst_reg + off16) ^= src_reg
 179  *   BPF_ADD | BPF_FETCH      src_reg = atomic_fetch_add(dst_reg + off16, src_reg);
 180  *   BPF_AND | BPF_FETCH      src_reg = atomic_fetch_and(dst_reg + off16, src_reg);
 181  *   BPF_OR | BPF_FETCH       src_reg = atomic_fetch_or(dst_reg + off16, src_reg);
 182  *   BPF_XOR | BPF_FETCH      src_reg = atomic_fetch_xor(dst_reg + off16, src_reg);
 183  *   BPF_XCHG                 src_reg = atomic_xchg(dst_reg + off16, src_reg)
 184  *   BPF_CMPXCHG              r0 = atomic_cmpxchg(dst_reg + off16, r0, src_reg)
 185  */
 186
 187 #define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF)                  \
 188         ((struct bpf_insn) {                                    \
 189                 .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC, \
 190                 .dst_reg = DST,                                 \
 191                 .src_reg = SRC,                                 \
 192                 .off   = OFF,                                   \
 193                 .imm   = OP })
 194
 195 /* Legacy alias */
 196 #define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF)
 197
 198 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */
 199
 200 #define BPF_ST_MEM(SIZE, DST, OFF, IMM)                         \
 201         ((struct bpf_insn) {                                    \
 202                 .code  = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM,     \
 203                 .dst_reg = DST,                                 \
 204                 .src_reg = 0,                                   \
 205                 .off   = OFF,                                   \
 206                 .imm   = IMM })
 207
 208 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */
 209
 210 #define BPF_JMP_REG(OP, DST, SRC, OFF)                          \
 211         ((struct bpf_insn) {                                    \
 212                 .code  = BPF_JMP | BPF_OP(OP) | BPF_X,          \
 213                 .dst_reg = DST,                                 \
 214                 .src_reg = SRC,                                 \
 215                 .off   = OFF,                                   \
 216                 .imm   = 0 })
 217
 218 /* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */
 219
 220 #define BPF_JMP32_REG(OP, DST, SRC, OFF)                        \
 221         ((struct bpf_insn) {                                    \
 222                 .code  = BPF_JMP32 | BPF_OP(OP) | BPF_X,        \
 223                 .dst_reg = DST,                                 \
 224                 .src_reg = SRC,                                 \
 225                 .off   = OFF,                                   \
 226                 .imm   = 0 })
 227
 228 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */
 229
 230 #define BPF_JMP_IMM(OP, DST, IMM, OFF)                          \
 231         ((struct bpf_insn) {                                    \
 232                 .code  = BPF_JMP | BPF_OP(OP) | BPF_K,          \
 233                 .dst_reg = DST,                                 \
 234                 .src_reg = 0,                                   \
 235                 .off   = OFF,                                   \
 236                 .imm   = IMM })
 237
 238 /* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */
 239
 240 #define BPF_JMP32_IMM(OP, DST, IMM, OFF)                        \
 241         ((struct bpf_insn) {                                    \
 242                 .code  = BPF_JMP32 | BPF_OP(OP) | BPF_K,        \
 243                 .dst_reg = DST,                                 \
 244                 .src_reg = 0,                                   \
 245                 .off   = OFF,                                   \
 246                 .imm   = IMM })
 247
 248 /* Unconditional jumps, goto pc + off16 */
 249
 250 #define BPF_JMP_A(OFF)                                          \
 251         ((struct bpf_insn) {                                    \
 252                 .code  = BPF_JMP | BPF_JA,                      \
 253                 .dst_reg = 0,                                   \
 254                 .src_reg = 0,                                   \
 255                 .off   = OFF,                                   \
 256                 .imm   = 0 })
 257
 258 /* Function call */
 259
 260 #define BPF_EMIT_CALL(FUNC)                                     \
 261         ((struct bpf_insn) {                                    \
 262                 .code  = BPF_JMP | BPF_CALL,                    \
 263                 .dst_reg = 0,                                   \
 264                 .src_reg = 0,                                   \
 265                 .off   = 0,                                     \
 266                 .imm   = ((FUNC) - BPF_FUNC_unspec) })
 267
 268 /* Raw code statement block */
 269
 270 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM)                  \
 271         ((struct bpf_insn) {                                    \
 272                 .code  = CODE,                                  \
 273                 .dst_reg = DST,                                 \
 274                 .src_reg = SRC,                                 \
 275                 .off   = OFF,                                   \
 276                 .imm   = IMM })
 277
 278 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */
 279
 280 #define BPF_LD_IMM64(DST, IMM)                                  \
 281         BPF_LD_IMM64_RAW(DST, 0, IMM)
 282
 283 #define BPF_LD_IMM64_RAW(DST, SRC, IMM)                         \
 284         ((struct bpf_insn) {                                    \
 285                 .code  = BPF_LD | BPF_DW | BPF_IMM,             \
 286                 .dst_reg = DST,                                 \
 287                 .src_reg = SRC,                                 \
 288                 .off   = 0,                                     \
 289                 .imm   = (__u32) (IMM) }),                      \
 290         ((struct bpf_insn) {                                    \
 291                 .code  = 0, /* zero is reserved opcode */       \
 292                 .dst_reg = 0,                                   \
 293                 .src_reg = 0,                                   \
 294                 .off   = 0,                                     \
 295                 .imm   = ((__u64) (IMM)) >> 32 })
 296
 297 #define BPF_LD_IMM64_RAW_FULL(DST, SRC, OFF1, OFF2, IMM1, IMM2) \
 298         ((struct bpf_insn) {                                    \
 299                 .code  = BPF_LD | BPF_DW | BPF_IMM,             \
 300                 .dst_reg = DST,                                 \
 301                 .src_reg = SRC,                                 \
 302                 .off   = OFF1,                                  \
 303                 .imm   = IMM1 }),                               \
 304         ((struct bpf_insn) {                                    \
 305                 .code  = 0, /* zero is reserved opcode */       \
 306                 .dst_reg = 0,                                   \
 307                 .src_reg = 0,                                   \
 308                 .off   = OFF2,                                  \
 309                 .imm   = IMM2 })
 310
 311 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */
 312
 313 #define BPF_LD_MAP_FD(DST, MAP_FD)                              \
 314         BPF_LD_IMM64_RAW_FULL(DST, BPF_PSEUDO_MAP_FD, 0, 0,     \
 315                               MAP_FD, 0)
 316
 317 #define BPF_LD_MAP_VALUE(DST, MAP_FD, VALUE_OFF)                \
 318         BPF_LD_IMM64_RAW_FULL(DST, BPF_PSEUDO_MAP_VALUE, 0, 0,  \
 319                               MAP_FD, VALUE_OFF)
 320
 321 /* Relative call */
 322
 323 #define BPF_CALL_REL(TGT)                                       \
 324         ((struct bpf_insn) {                                    \
 325                 .code  = BPF_JMP | BPF_CALL,                    \
 326                 .dst_reg = 0,                                   \
 327                 .src_reg = BPF_PSEUDO_CALL,                     \
 328                 .off   = 0,                                     \
 329                 .imm   = TGT })
 330
 331 /* Program exit */
 332
 333 #define BPF_EXIT_INSN()                                         \
 334         ((struct bpf_insn) {                                    \
 335                 .code  = BPF_JMP | BPF_EXIT,                    \
 336                 .dst_reg = 0,                                   \
 337                 .src_reg = 0,                                   \
 338                 .off   = 0,                                     \
 339                 .imm   = 0 })
 340
 341 #endif /* __TOOLS_LINUX_FILTER_H */