1 /* $OpenBSD: asr_private.h,v 1.43 2017/02/23 17:04:02 eric Exp $ */ 2 /* 3 * Copyright (c) 2012 Eric Faurot <eric@openbsd.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #include <stdio.h> 19 20 #define QR_MASK (0x1 << 15) 21 #define OPCODE_MASK (0xf << 11) 22 #define AA_MASK (0x1 << 10) 23 #define TC_MASK (0x1 << 9) 24 #define RD_MASK (0x1 << 8) 25 #define RA_MASK (0x1 << 7) 26 #define Z_MASK (0x7 << 4) 27 #define RCODE_MASK (0xf) 28 29 #define OPCODE(v) ((v) & OPCODE_MASK) 30 #define RCODE(v) ((v) & RCODE_MASK) 31 32 33 struct asr_pack { 34 char *buf; 35 size_t len; 36 size_t offset; 37 int err; 38 }; 39 40 struct asr_unpack { 41 const char *buf; 42 size_t len; 43 size_t offset; 44 int err; 45 }; 46 47 struct asr_dns_header { 48 uint16_t id; 49 uint16_t flags; 50 uint16_t qdcount; 51 uint16_t ancount; 52 uint16_t nscount; 53 uint16_t arcount; 54 }; 55 56 struct asr_dns_query { 57 char q_dname[MAXDNAME]; 58 uint16_t q_type; 59 uint16_t q_class; 60 }; 61 62 struct asr_dns_rr { 63 char rr_dname[MAXDNAME]; 64 uint16_t rr_type; 65 uint16_t rr_class; 66 uint32_t rr_ttl; 67 union { 68 struct { 69 char cname[MAXDNAME]; 70 } cname; 71 struct { 72 uint16_t preference; 73 char exchange[MAXDNAME]; 74 } mx; 75 struct { 76 char nsname[MAXDNAME]; 77 } ns; 78 struct { 79 char ptrname[MAXDNAME]; 80 } ptr; 81 struct { 82 char mname[MAXDNAME]; 83 char rname[MAXDNAME]; 84 uint32_t serial; 85 uint32_t refresh; 86 uint32_t retry; 87 uint32_t expire; 88 uint32_t minimum; 89 } soa; 90 struct { 91 struct in_addr addr; 92 } in_a; 93 struct { 94 struct in6_addr addr6; 95 } in_aaaa; 96 struct { 97 uint16_t rdlen; 98 const void *rdata; 99 } other; 100 } rr; 101 }; 102 103 104 #define ASR_MAXNS 5 105 #define ASR_MAXDB 3 106 #define ASR_MAXDOM 10 107 108 enum async_type { 109 ASR_SEND, 110 ASR_SEARCH, 111 ASR_GETRRSETBYNAME, 112 ASR_GETHOSTBYNAME, 113 ASR_GETHOSTBYADDR, 114 ASR_GETNETBYNAME, 115 ASR_GETNETBYADDR, 116 ASR_GETADDRINFO, 117 ASR_GETNAMEINFO, 118 }; 119 120 #define ASR_DB_FILE 'f' 121 #define ASR_DB_DNS 'b' 122 123 struct asr_ctx { 124 int ac_refcount; 125 int ac_options; 126 int ac_ndots; 127 char *ac_domain; 128 int ac_domcount; 129 char *ac_dom[ASR_MAXDOM]; 130 int ac_dbcount; 131 char ac_db[ASR_MAXDB + 1]; 132 int ac_family[3]; 133 134 int ac_nscount; 135 int ac_nstimeout; 136 int ac_nsretries; 137 struct sockaddr *ac_ns[ASR_MAXNS]; 138 139 }; 140 141 struct asr { 142 pid_t a_pid; 143 time_t a_mtime; 144 time_t a_rtime; 145 struct asr_ctx *a_ctx; 146 }; 147 148 #define ASYNC_COND 0 149 #define ASYNC_DONE 1 150 151 #define ASYNC_DOM_FQDN 0x00000001 152 #define ASYNC_DOM_NDOTS 0x00000002 153 #define ASYNC_DOM_DOMAIN 0x00000004 154 #define ASYNC_DOM_ASIS 0x00000008 155 156 #define ASYNC_NODATA 0x00000100 157 #define ASYNC_AGAIN 0x00000200 158 159 #define ASYNC_EXTOBUF 0x00002000 160 161 #define ASYNC_NO_INET 0x00010000 162 #define ASYNC_NO_INET6 0x00020000 163 164 struct asr_query { 165 int (*as_run)(struct asr_query *, struct asr_result *); 166 struct asr_ctx *as_ctx; 167 int as_type; 168 int as_state; 169 170 /* cond */ 171 int as_timeout; 172 int as_fd; 173 struct asr_query *as_subq; 174 175 /* loop indices in ctx */ 176 int as_dom_step; 177 int as_dom_idx; 178 int as_dom_flags; 179 int as_family_idx; 180 int as_db_idx; 181 182 int as_count; 183 184 union { 185 struct { 186 int flags; 187 uint16_t reqid; 188 int class; 189 int type; 190 char *dname; /* not fqdn! */ 191 int rcode; /* response code */ 192 int ancount; /* answer count */ 193 194 int nsidx; 195 int nsloop; 196 197 /* io buffers for query/response */ 198 unsigned char *obuf; 199 size_t obuflen; 200 size_t obufsize; 201 unsigned char *ibuf; 202 size_t ibuflen; 203 size_t ibufsize; 204 size_t datalen; /* for tcp io */ 205 uint16_t pktlen; 206 } dns; 207 208 struct { 209 int flags; 210 int class; 211 int type; 212 char *name; 213 int saved_h_errno; 214 } search; 215 216 struct { 217 int flags; 218 int class; 219 int type; 220 char *name; 221 } rrset; 222 223 struct { 224 char *name; 225 int family; 226 char addr[16]; 227 int addrlen; 228 int subq_h_errno; 229 } hostnamadr; 230 231 struct { 232 char *name; 233 int family; 234 in_addr_t addr; 235 } netnamadr; 236 237 struct { 238 char *hostname; 239 char *servname; 240 int port_tcp; 241 int port_udp; 242 union { 243 struct sockaddr sa; 244 struct sockaddr_in sain; 245 struct sockaddr_in6 sain6; 246 } sa; 247 248 struct addrinfo hints; 249 char *fqdn; 250 struct addrinfo *aifirst; 251 struct addrinfo *ailast; 252 int flags; 253 } ai; 254 255 struct { 256 char *hostname; 257 char *servname; 258 size_t hostnamelen; 259 size_t servnamelen; 260 union { 261 struct sockaddr sa; 262 struct sockaddr_in sain; 263 struct sockaddr_in6 sain6; 264 } sa; 265 int flags; 266 } ni; 267 #define MAXTOKEN 10 268 } as; 269 270 }; 271 272 #define AS_DB(p) ((p)->as_ctx->ac_db[(p)->as_db_idx - 1]) 273 #define AS_FAMILY(p) ((p)->as_ctx->ac_family[(p)->as_family_idx]) 274 275 enum asr_state { 276 ASR_STATE_INIT, 277 ASR_STATE_NEXT_DOMAIN, 278 ASR_STATE_NEXT_DB, 279 ASR_STATE_SAME_DB, 280 ASR_STATE_NEXT_FAMILY, 281 ASR_STATE_NEXT_NS, 282 ASR_STATE_UDP_SEND, 283 ASR_STATE_UDP_RECV, 284 ASR_STATE_TCP_WRITE, 285 ASR_STATE_TCP_READ, 286 ASR_STATE_PACKET, 287 ASR_STATE_SUBQUERY, 288 ASR_STATE_NOT_FOUND, 289 ASR_STATE_HALT, 290 }; 291 292 #define MAXPACKETSZ 4096 293 294 __BEGIN_HIDDEN_DECLS 295 296 /* asr_utils.c */ 297 void _asr_pack_init(struct asr_pack *, char *, size_t); 298 int _asr_pack_header(struct asr_pack *, const struct asr_dns_header *); 299 int _asr_pack_query(struct asr_pack *, uint16_t, uint16_t, const char *); 300 int _asr_pack_edns0(struct asr_pack *, uint16_t); 301 void _asr_unpack_init(struct asr_unpack *, const char *, size_t); 302 int _asr_unpack_header(struct asr_unpack *, struct asr_dns_header *); 303 int _asr_unpack_query(struct asr_unpack *, struct asr_dns_query *); 304 int _asr_unpack_rr(struct asr_unpack *, struct asr_dns_rr *); 305 int _asr_sockaddr_from_str(struct sockaddr *, int, const char *); 306 ssize_t _asr_dname_from_fqdn(const char *, char *, size_t); 307 ssize_t _asr_addr_as_fqdn(const char *, int, char *, size_t); 308 309 /* asr.c */ 310 void _asr_resolver_done(void *); 311 struct asr_ctx *_asr_use_resolver(void *); 312 struct asr_ctx *_asr_no_resolver(void); 313 void _asr_ctx_unref(struct asr_ctx *); 314 struct asr_query *_asr_async_new(struct asr_ctx *, int); 315 void _asr_async_free(struct asr_query *); 316 size_t _asr_make_fqdn(const char *, const char *, char *, size_t); 317 char *_asr_strdname(const char *, char *, size_t); 318 int _asr_iter_db(struct asr_query *); 319 int _asr_parse_namedb_line(FILE *, char **, int, char *, size_t); 320 321 /* *_async.c */ 322 struct asr_query *_res_query_async_ctx(const char *, int, int, struct asr_ctx *); 323 struct asr_query *_res_search_async_ctx(const char *, int, int, struct asr_ctx *); 324 struct asr_query *_gethostbyaddr_async_ctx(const void *, socklen_t, int, 325 struct asr_ctx *); 326 327 int _asr_iter_domain(struct asr_query *, const char *, char *, size_t); 328 329 #ifdef DEBUG 330 331 #define DPRINT(...) do { if(_asr_debug) { \ 332 fprintf(_asr_debug, __VA_ARGS__); \ 333 } } while (0) 334 #define DPRINT_PACKET(n, p, s) do { if(_asr_debug) { \ 335 fprintf(_asr_debug, "----- %s -----\n", n); \ 336 _asr_dump_packet(_asr_debug, (p), (s)); \ 337 fprintf(_asr_debug, "--------------\n"); \ 338 } } while (0) 339 340 #else /* DEBUG */ 341 342 #define DPRINT(...) 343 #define DPRINT_PACKET(...) 344 345 #endif /* DEBUG */ 346 347 const char *_asr_querystr(int); 348 const char *_asr_statestr(int); 349 const char *_asr_transitionstr(int); 350 const char *_asr_print_sockaddr(const struct sockaddr *, char *, size_t); 351 void _asr_dump_config(FILE *, struct asr *); 352 void _asr_dump_packet(FILE *, const void *, size_t); 353 354 extern FILE *_asr_debug; 355 356 #define async_set_state(a, s) do { \ 357 DPRINT("asr: [%s@%p] %s -> %s\n", \ 358 _asr_querystr((a)->as_type), \ 359 as, \ 360 _asr_statestr((a)->as_state), \ 361 _asr_statestr((s))); \ 362 (a)->as_state = (s); } while (0) 363 364 __END_HIDDEN_DECLS 365