1 /* 2 * bpf_util.h BPF common code 3 * 4 * This program is free software; you can distribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Authors: Daniel Borkmann <daniel (at) iogearbox.net> 10 * Jiri Pirko <jiri (at) resnulli.us> 11 */ 12 13 #ifndef __BPF_UTIL__ 14 #define __BPF_UTIL__ 15 16 #include <linux/bpf.h> 17 #include <linux/filter.h> 18 #include <linux/magic.h> 19 #include <linux/elf-em.h> 20 #include <linux/if_alg.h> 21 22 #include "utils.h" 23 #include "bpf_scm.h" 24 25 #define BPF_ENV_UDS "TC_BPF_UDS" 26 #define BPF_ENV_MNT "TC_BPF_MNT" 27 28 #ifndef BPF_MAX_LOG 29 # define BPF_MAX_LOG 4096 30 #endif 31 32 #define BPF_DIR_GLOBALS "globals" 33 34 #ifndef BPF_FS_MAGIC 35 # define BPF_FS_MAGIC 0xcafe4a11 36 #endif 37 38 #define BPF_DIR_MNT "/sys/fs/bpf" 39 40 #ifndef TRACEFS_MAGIC 41 # define TRACEFS_MAGIC 0x74726163 42 #endif 43 44 #define TRACE_DIR_MNT "/sys/kernel/tracing" 45 46 #ifndef AF_ALG 47 # define AF_ALG 38 48 #endif 49 50 #ifndef EM_BPF 51 # define EM_BPF 247 52 #endif 53 54 struct bpf_cfg_ops { 55 void (*cbpf_cb)(void *nl, const struct sock_filter *ops, int ops_len); 56 void (*ebpf_cb)(void *nl, int fd, const char *annotation); 57 }; 58 59 struct bpf_cfg_in { 60 const char *object; 61 const char *section; 62 const char *uds; 63 int argc; 64 char **argv; 65 struct sock_filter *ops; 66 }; 67 68 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */ 69 70 #define BPF_ALU64_REG(OP, DST, SRC) \ 71 ((struct bpf_insn) { \ 72 .code = BPF_ALU64 | BPF_OP(OP) | BPF_X, \ 73 .dst_reg = DST, \ 74 .src_reg = SRC, \ 75 .off = 0, \ 76 .imm = 0 }) 77 78 #define BPF_ALU32_REG(OP, DST, SRC) \ 79 ((struct bpf_insn) { \ 80 .code = BPF_ALU | BPF_OP(OP) | BPF_X, \ 81 .dst_reg = DST, \ 82 .src_reg = SRC, \ 83 .off = 0, \ 84 .imm = 0 }) 85 86 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */ 87 88 #define BPF_ALU64_IMM(OP, DST, IMM) \ 89 ((struct bpf_insn) { \ 90 .code = BPF_ALU64 | BPF_OP(OP) | BPF_K, \ 91 .dst_reg = DST, \ 92 .src_reg = 0, \ 93 .off = 0, \ 94 .imm = IMM }) 95 96 #define BPF_ALU32_IMM(OP, DST, IMM) \ 97 ((struct bpf_insn) { \ 98 .code = BPF_ALU | BPF_OP(OP) | BPF_K, \ 99 .dst_reg = DST, \ 100 .src_reg = 0, \ 101 .off = 0, \ 102 .imm = IMM }) 103 104 /* Short form of mov, dst_reg = src_reg */ 105 106 #define BPF_MOV64_REG(DST, SRC) \ 107 ((struct bpf_insn) { \ 108 .code = BPF_ALU64 | BPF_MOV | BPF_X, \ 109 .dst_reg = DST, \ 110 .src_reg = SRC, \ 111 .off = 0, \ 112 .imm = 0 }) 113 114 #define BPF_MOV32_REG(DST, SRC) \ 115 ((struct bpf_insn) { \ 116 .code = BPF_ALU | BPF_MOV | BPF_X, \ 117 .dst_reg = DST, \ 118 .src_reg = SRC, \ 119 .off = 0, \ 120 .imm = 0 }) 121 122 /* Short form of mov, dst_reg = imm32 */ 123 124 #define BPF_MOV64_IMM(DST, IMM) \ 125 ((struct bpf_insn) { \ 126 .code = BPF_ALU64 | BPF_MOV | BPF_K, \ 127 .dst_reg = DST, \ 128 .src_reg = 0, \ 129 .off = 0, \ 130 .imm = IMM }) 131 132 #define BPF_MOV32_IMM(DST, IMM) \ 133 ((struct bpf_insn) { \ 134 .code = BPF_ALU | BPF_MOV | BPF_K, \ 135 .dst_reg = DST, \ 136 .src_reg = 0, \ 137 .off = 0, \ 138 .imm = IMM }) 139 140 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */ 141 #define BPF_LD_IMM64(DST, IMM) \ 142 BPF_LD_IMM64_RAW(DST, 0, IMM) 143 144 #define BPF_LD_IMM64_RAW(DST, SRC, IMM) \ 145 ((struct bpf_insn) { \ 146 .code = BPF_LD | BPF_DW | BPF_IMM, \ 147 .dst_reg = DST, \ 148 .src_reg = SRC, \ 149 .off = 0, \ 150 .imm = (__u32) (IMM) }), \ 151 ((struct bpf_insn) { \ 152 .code = 0, /* zero is reserved opcode */ \ 153 .dst_reg = 0, \ 154 .src_reg = 0, \ 155 .off = 0, \ 156 .imm = ((__u64) (IMM)) >> 32 }) 157 158 #ifndef BPF_PSEUDO_MAP_FD 159 # define BPF_PSEUDO_MAP_FD 1 160 #endif 161 162 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */ 163 #define BPF_LD_MAP_FD(DST, MAP_FD) \ 164 BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD) 165 166 167 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */ 168 169 #define BPF_LD_ABS(SIZE, IMM) \ 170 ((struct bpf_insn) { \ 171 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS, \ 172 .dst_reg = 0, \ 173 .src_reg = 0, \ 174 .off = 0, \ 175 .imm = IMM }) 176 177 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */ 178 179 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF) \ 180 ((struct bpf_insn) { \ 181 .code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM, \ 182 .dst_reg = DST, \ 183 .src_reg = SRC, \ 184 .off = OFF, \ 185 .imm = 0 }) 186 187 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */ 188 189 #define BPF_STX_MEM(SIZE, DST, SRC, OFF) \ 190 ((struct bpf_insn) { \ 191 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM, \ 192 .dst_reg = DST, \ 193 .src_reg = SRC, \ 194 .off = OFF, \ 195 .imm = 0 }) 196 197 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */ 198 199 #define BPF_ST_MEM(SIZE, DST, OFF, IMM) \ 200 ((struct bpf_insn) { \ 201 .code = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM, \ 202 .dst_reg = DST, \ 203 .src_reg = 0, \ 204 .off = OFF, \ 205 .imm = IMM }) 206 207 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */ 208 209 #define BPF_JMP_REG(OP, DST, SRC, OFF) \ 210 ((struct bpf_insn) { \ 211 .code = BPF_JMP | BPF_OP(OP) | BPF_X, \ 212 .dst_reg = DST, \ 213 .src_reg = SRC, \ 214 .off = OFF, \ 215 .imm = 0 }) 216 217 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */ 218 219 #define BPF_JMP_IMM(OP, DST, IMM, OFF) \ 220 ((struct bpf_insn) { \ 221 .code = BPF_JMP | BPF_OP(OP) | BPF_K, \ 222 .dst_reg = DST, \ 223 .src_reg = 0, \ 224 .off = OFF, \ 225 .imm = IMM }) 226 227 /* Raw code statement block */ 228 229 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM) \ 230 ((struct bpf_insn) { \ 231 .code = CODE, \ 232 .dst_reg = DST, \ 233 .src_reg = SRC, \ 234 .off = OFF, \ 235 .imm = IMM }) 236 237 /* Program exit */ 238 239 #define BPF_EXIT_INSN() \ 240 ((struct bpf_insn) { \ 241 .code = BPF_JMP | BPF_EXIT, \ 242 .dst_reg = 0, \ 243 .src_reg = 0, \ 244 .off = 0, \ 245 .imm = 0 }) 246 247 int bpf_parse_common(enum bpf_prog_type type, struct bpf_cfg_in *cfg, 248 const struct bpf_cfg_ops *ops, void *nl); 249 250 const char *bpf_prog_to_default_section(enum bpf_prog_type type); 251 252 int bpf_graft_map(const char *map_path, uint32_t *key, int argc, char **argv); 253 int bpf_trace_pipe(void); 254 255 void bpf_print_ops(FILE *f, struct rtattr *bpf_ops, __u16 len); 256 257 int bpf_prog_load(enum bpf_prog_type type, const struct bpf_insn *insns, 258 size_t size_insns, const char *license, char *log, 259 size_t size_log); 260 261 int bpf_prog_attach_fd(int prog_fd, int target_fd, enum bpf_attach_type type); 262 int bpf_prog_detach_fd(int target_fd, enum bpf_attach_type type); 263 264 int bpf_dump_prog_info(FILE *f, uint32_t id); 265 266 #ifdef HAVE_ELF 267 int bpf_send_map_fds(const char *path, const char *obj); 268 int bpf_recv_map_fds(const char *path, int *fds, struct bpf_map_aux *aux, 269 unsigned int entries); 270 #else 271 static inline int bpf_send_map_fds(const char *path, const char *obj) 272 { 273 return 0; 274 } 275 276 static inline int bpf_recv_map_fds(const char *path, int *fds, 277 struct bpf_map_aux *aux, 278 unsigned int entries) 279 { 280 return -1; 281 } 282 #endif /* HAVE_ELF */ 283 #endif /* __BPF_UTIL__ */ 284
