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