tools/include/linux/filter.h

   1 /*
   2  * Linux Socket Filter Data Structures
   3  */
   4 #ifndef __TOOLS_LINUX_FILTER_H
   5 #define __TOOLS_LINUX_FILTER_H
   6
   7 #include <linux/bpf.h>
   8
   9 /* ArgX, context and stack frame pointer register positions. Note,
  10  * Arg1, Arg2, Arg3, etc are used as argument mappings of function
  11  * calls in BPF_CALL instruction.
  12  */
  13 #define BPF_REG_ARG1    BPF_REG_1
  14 #define BPF_REG_ARG2    BPF_REG_2
  15 #define BPF_REG_ARG3    BPF_REG_3
  16 #define BPF_REG_ARG4    BPF_REG_4
  17 #define BPF_REG_ARG5    BPF_REG_5
  18 #define BPF_REG_CTX     BPF_REG_6
  19 #define BPF_REG_FP      BPF_REG_10
  20
  21 /* Additional register mappings for converted user programs. */
  22 #define BPF_REG_A       BPF_REG_0
  23 #define BPF_REG_X       BPF_REG_7
  24 #define BPF_REG_TMP     BPF_REG_8
  25
  26 /* BPF program can access up to 512 bytes of stack space. */
  27 #define MAX_BPF_STACK   512
  28
  29 /* Helper macros for filter block array initializers. */
  30
  31 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */
  32
  33 #define BPF_ALU64_REG(OP, DST, SRC)                             \
  34         ((struct bpf_insn) {                                    \
  35                 .code  = BPF_ALU64 | BPF_OP(OP) | BPF_X,        \
  36                 .dst_reg = DST,                                 \
  37                 .src_reg = SRC,                                 \
  38                 .off   = 0,                                     \
  39                 .imm   = 0 })
  40
  41 #define BPF_ALU32_REG(OP, DST, SRC)                             \
  42         ((struct bpf_insn) {                                    \
  43                 .code  = BPF_ALU | BPF_OP(OP) | BPF_X,          \
  44                 .dst_reg = DST,                                 \
  45                 .src_reg = SRC,                                 \
  46                 .off   = 0,                                     \
  47                 .imm   = 0 })
  48
  49 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */
  50
  51 #define BPF_ALU64_IMM(OP, DST, IMM)                             \
  52         ((struct bpf_insn) {                                    \
  53                 .code  = BPF_ALU64 | BPF_OP(OP) | BPF_K,        \
  54                 .dst_reg = DST,                                 \
  55                 .src_reg = 0,                                   \
  56                 .off   = 0,                                     \
  57                 .imm   = IMM })
  58
  59 #define BPF_ALU32_IMM(OP, DST, IMM)                             \
  60         ((struct bpf_insn) {                                    \
  61                 .code  = BPF_ALU | BPF_OP(OP) | BPF_K,          \
  62                 .dst_reg = DST,                                 \
  63                 .src_reg = 0,                                   \
  64                 .off   = 0,                                     \
  65                 .imm   = IMM })
  66
  67 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */
  68
  69 #define BPF_ENDIAN(TYPE, DST, LEN)                              \
  70         ((struct bpf_insn) {                                    \
  71                 .code  = BPF_ALU | BPF_END | BPF_SRC(TYPE),     \
  72                 .dst_reg = DST,                                 \
  73                 .src_reg = 0,                                   \
  74                 .off   = 0,                                     \
  75                 .imm   = LEN })
  76
  77 /* Short form of mov, dst_reg = src_reg */
  78
  79 #define BPF_MOV64_REG(DST, SRC)                                 \
  80         ((struct bpf_insn) {                                    \
  81                 .code  = BPF_ALU64 | BPF_MOV | BPF_X,           \
  82                 .dst_reg = DST,                                 \
  83                 .src_reg = SRC,                                 \
  84                 .off   = 0,                                     \
  85                 .imm   = 0 })
  86
  87 #define BPF_MOV32_REG(DST, SRC)                                 \
  88         ((struct bpf_insn) {                                    \
  89                 .code  = BPF_ALU | BPF_MOV | BPF_X,             \
  90                 .dst_reg = DST,                                 \
  91                 .src_reg = SRC,                                 \
  92                 .off   = 0,                                     \
  93                 .imm   = 0 })
  94
  95 /* Short form of mov, dst_reg = imm32 */
  96
  97 #define BPF_MOV64_IMM(DST, IMM)                                 \
  98         ((struct bpf_insn) {                                    \
  99                 .code  = BPF_ALU64 | BPF_MOV | BPF_K,           \
 100                 .dst_reg = DST,                                 \
 101                 .src_reg = 0,                                   \
 102                 .off   = 0,                                     \
 103                 .imm   = IMM })
 104
 105 #define BPF_MOV32_IMM(DST, IMM)                                 \
 106         ((struct bpf_insn) {                                    \
 107                 .code  = BPF_ALU | BPF_MOV | BPF_K,             \
 108                 .dst_reg = DST,                                 \
 109                 .src_reg = 0,                                   \
 110                 .off   = 0,                                     \
 111                 .imm   = IMM })
 112
 113 /* Short form of mov based on type,  BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */
 114
 115 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM)                      \
 116         ((struct bpf_insn) {                                    \
 117                 .code  = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE),   \
 118                 .dst_reg = DST,                                 \
 119                 .src_reg = SRC,                                 \
 120                 .off   = 0,                                     \
 121                 .imm   = IMM })
 122
 123 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM)                      \
 124         ((struct bpf_insn) {                                    \
 125                 .code  = BPF_ALU | BPF_MOV | BPF_SRC(TYPE),     \
 126                 .dst_reg = DST,                                 \
 127                 .src_reg = SRC,                                 \
 128                 .off   = 0,                                     \
 129                 .imm   = IMM })
 130
 131 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */
 132
 133 #define BPF_LD_ABS(SIZE, IMM)                                   \
 134         ((struct bpf_insn) {                                    \
 135                 .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS,     \
 136                 .dst_reg = 0,                                   \
 137                 .src_reg = 0,                                   \
 138                 .off   = 0,                                     \
 139                 .imm   = IMM })
 140
 141 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */
 142
 143 #define BPF_LD_IND(SIZE, SRC, IMM)                              \
 144         ((struct bpf_insn) {                                    \
 145                 .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_IND,     \
 146                 .dst_reg = 0,                                   \
 147                 .src_reg = SRC,                                 \
 148                 .off   = 0,                                     \
 149                 .imm   = IMM })
 150
 151 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */
 152
 153 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF)                        \
 154         ((struct bpf_insn) {                                    \
 155                 .code  = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM,    \
 156                 .dst_reg = DST,                                 \
 157                 .src_reg = SRC,                                 \
 158                 .off   = OFF,                                   \
 159                 .imm   = 0 })
 160
 161 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */
 162
 163 #define BPF_STX_MEM(SIZE, DST, SRC, OFF)                        \
 164         ((struct bpf_insn) {                                    \
 165                 .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM,    \
 166                 .dst_reg = DST,                                 \
 167                 .src_reg = SRC,                                 \
 168                 .off   = OFF,                                   \
 169                 .imm   = 0 })
 170
 171 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */
 172
 173 #define BPF_ST_MEM(SIZE, DST, OFF, IMM)                         \
 174         ((struct bpf_insn) {                                    \
 175                 .code  = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM,     \
 176                 .dst_reg = DST,                                 \
 177                 .src_reg = 0,                                   \
 178                 .off   = OFF,                                   \
 179                 .imm   = IMM })
 180
 181 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */
 182
 183 #define BPF_JMP_REG(OP, DST, SRC, OFF)                          \
 184         ((struct bpf_insn) {                                    \
 185                 .code  = BPF_JMP | BPF_OP(OP) | BPF_X,          \
 186                 .dst_reg = DST,                                 \
 187                 .src_reg = SRC,                                 \
 188                 .off   = OFF,                                   \
 189                 .imm   = 0 })
 190
 191 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */
 192
 193 #define BPF_JMP_IMM(OP, DST, IMM, OFF)                          \
 194         ((struct bpf_insn) {                                    \
 195                 .code  = BPF_JMP | BPF_OP(OP) | BPF_K,          \
 196                 .dst_reg = DST,                                 \
 197                 .src_reg = 0,                                   \
 198                 .off   = OFF,                                   \
 199                 .imm   = IMM })
 200
 201 /* Function call */
 202
 203 #define BPF_EMIT_CALL(FUNC)                                     \
 204         ((struct bpf_insn) {                                    \
 205                 .code  = BPF_JMP | BPF_CALL,                    \
 206                 .dst_reg = 0,                                   \
 207                 .src_reg = 0,                                   \
 208                 .off   = 0,                                     \
 209                 .imm   = ((FUNC) - BPF_FUNC_unspec) })
 210
 211 /* Raw code statement block */
 212
 213 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM)                  \
 214         ((struct bpf_insn) {                                    \
 215                 .code  = CODE,                                  \
 216                 .dst_reg = DST,                                 \
 217                 .src_reg = SRC,                                 \
 218                 .off   = OFF,                                   \
 219                 .imm   = IMM })
 220
 221 /* Program exit */
 222
 223 #define BPF_EXIT_INSN()                                         \
 224         ((struct bpf_insn) {                                    \
 225                 .code  = BPF_JMP | BPF_EXIT,                    \
 226                 .dst_reg = 0,                                   \
 227                 .src_reg = 0,                                   \
 228                 .off   = 0,                                     \
 229                 .imm   = 0 })
 230
 231 #endif /* __TOOLS_LINUX_FILTER_H */