github.com/zhyoulun/cilium@v1.6.12/contrib/codegen/hexgen.h (about)

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