1 /* $OpenBSD: asr_private.h,v 1.47 2018/04/28 15:16:49 schwarze 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 #include "asr_compat.h" 21 22 #define QR_MASK (0x1 << 15) 23 #define OPCODE_MASK (0xf << 11) 24 #define AA_MASK (0x1 << 10) 25 #define TC_MASK (0x1 << 9) 26 #define RD_MASK (0x1 << 8) 27 #define RA_MASK (0x1 << 7) 28 #define Z_MASK (0x1 << 6) 29 #define AD_MASK (0x1 << 5) 30 #define CD_MASK (0x1 << 4) 31 #define RCODE_MASK (0xf) 32 33 #define OPCODE(v) ((v) & OPCODE_MASK) 34 #define RCODE(v) ((v) & RCODE_MASK) 35 36 37 struct asr_pack { 38 char *buf; 39 size_t len; 40 size_t offset; 41 int err; 42 }; 43 44 struct asr_unpack { 45 const char *buf; 46 size_t len; 47 size_t offset; 48 int err; 49 }; 50 51 struct asr_dns_header { 52 uint16_t id; 53 uint16_t flags; 54 uint16_t qdcount; 55 uint16_t ancount; 56 uint16_t nscount; 57 uint16_t arcount; 58 }; 59 60 struct asr_dns_query { 61 char q_dname[MAXDNAME]; 62 uint16_t q_type; 63 uint16_t q_class; 64 }; 65 66 struct asr_dns_rr { 67 char rr_dname[MAXDNAME]; 68 uint16_t rr_type; 69 uint16_t rr_class; 70 uint32_t rr_ttl; 71 union { 72 struct { 73 char cname[MAXDNAME]; 74 } cname; 75 struct { 76 uint16_t preference; 77 char exchange[MAXDNAME]; 78 } mx; 79 struct { 80 char nsname[MAXDNAME]; 81 } ns; 82 struct { 83 char ptrname[MAXDNAME]; 84 } ptr; 85 struct { 86 char mname[MAXDNAME]; 87 char rname[MAXDNAME]; 88 uint32_t serial; 89 uint32_t refresh; 90 uint32_t retry; 91 uint32_t expire; 92 uint32_t minimum; 93 } soa; 94 struct { 95 struct in_addr addr; 96 } in_a; 97 struct { 98 struct in6_addr addr6; 99 } in_aaaa; 100 struct { 101 uint16_t rdlen; 102 const void *rdata; 103 } other; 104 } rr; 105 }; 106 107 108 #define ASR_MAXNS 5 109 #define ASR_MAXDB 3 110 #define ASR_MAXDOM 10 111 112 enum async_type { 113 ASR_SEND, 114 ASR_SEARCH, 115 ASR_GETRRSETBYNAME, 116 ASR_GETHOSTBYNAME, 117 ASR_GETHOSTBYADDR, 118 ASR_GETADDRINFO, 119 ASR_GETNAMEINFO, 120 }; 121 122 #define ASR_DB_FILE 'f' 123 #define ASR_DB_DNS 'b' 124 125 struct asr_ctx { 126 int ac_refcount; 127 int ac_options; 128 int ac_ndots; 129 char *ac_domain; 130 int ac_domcount; 131 char *ac_dom[ASR_MAXDOM]; 132 int ac_dbcount; 133 char ac_db[ASR_MAXDB + 1]; 134 int ac_family[3]; 135 136 int ac_nscount; 137 int ac_nstimeout; 138 int ac_nsretries; 139 struct sockaddr *ac_ns[ASR_MAXNS]; 140 141 }; 142 143 struct asr { 144 pid_t a_pid; 145 time_t a_mtime; 146 time_t a_rtime; 147 struct asr_ctx *a_ctx; 148 }; 149 150 #define ASYNC_COND 0 151 #define ASYNC_DONE 1 152 153 #define ASYNC_DOM_FQDN 0x00000001 154 #define ASYNC_DOM_NDOTS 0x00000002 155 #define ASYNC_DOM_DOMAIN 0x00000004 156 #define ASYNC_DOM_ASIS 0x00000008 157 158 #define ASYNC_NODATA 0x00000100 159 #define ASYNC_AGAIN 0x00000200 160 161 #define ASYNC_GETNET 0x00001000 162 #define ASYNC_EXTOBUF 0x00002000 163 164 #define ASYNC_NO_INET 0x00010000 165 #define ASYNC_NO_INET6 0x00020000 166 167 struct asr_query { 168 int (*as_run)(struct asr_query *, struct asr_result *); 169 struct asr_ctx *as_ctx; 170 int as_type; 171 int as_flags; 172 int as_state; 173 174 /* cond */ 175 int as_timeout; 176 int as_fd; 177 struct asr_query *as_subq; 178 179 /* loop indices in ctx */ 180 int as_dom_step; 181 int as_dom_idx; 182 int as_dom_flags; 183 int as_family_idx; 184 int as_db_idx; 185 186 int as_count; 187 188 union { 189 struct { 190 uint16_t reqid; 191 int class; 192 int type; 193 char *dname; /* not fqdn! */ 194 int rcode; /* response code */ 195 int ancount; /* answer count */ 196 197 int nsidx; 198 int nsloop; 199 200 /* io buffers for query/response */ 201 unsigned char *obuf; 202 size_t obuflen; 203 size_t obufsize; 204 unsigned char *ibuf; 205 size_t ibuflen; 206 size_t ibufsize; 207 size_t datalen; /* for tcp io */ 208 uint16_t pktlen; 209 } dns; 210 211 struct { 212 int class; 213 int type; 214 char *name; 215 int saved_h_errno; 216 } search; 217 218 struct { 219 int flags; 220 int class; 221 int type; 222 char *name; 223 } rrset; 224 225 struct { 226 char *name; 227 int family; 228 char addr[16]; 229 int addrlen; 230 int subq_h_errno; 231 } hostnamadr; 232 233 struct { 234 char *hostname; 235 char *servname; 236 int port_tcp; 237 int port_udp; 238 union { 239 struct sockaddr sa; 240 struct sockaddr_in sain; 241 struct sockaddr_in6 sain6; 242 } sa; 243 244 struct addrinfo hints; 245 char *fqdn; 246 struct addrinfo *aifirst; 247 struct addrinfo *ailast; 248 } ai; 249 250 struct { 251 char *hostname; 252 char *servname; 253 size_t hostnamelen; 254 size_t servnamelen; 255 union { 256 struct sockaddr sa; 257 struct sockaddr_in sain; 258 struct sockaddr_in6 sain6; 259 } sa; 260 int flags; 261 } ni; 262 #define MAXTOKEN 10 263 } as; 264 265 }; 266 267 #define AS_DB(p) ((p)->as_ctx->ac_db[(p)->as_db_idx - 1]) 268 #define AS_FAMILY(p) ((p)->as_ctx->ac_family[(p)->as_family_idx]) 269 270 enum asr_state { 271 ASR_STATE_INIT, 272 ASR_STATE_NEXT_DOMAIN, 273 ASR_STATE_NEXT_DB, 274 ASR_STATE_SAME_DB, 275 ASR_STATE_NEXT_FAMILY, 276 ASR_STATE_NEXT_NS, 277 ASR_STATE_UDP_SEND, 278 ASR_STATE_UDP_RECV, 279 ASR_STATE_TCP_WRITE, 280 ASR_STATE_TCP_READ, 281 ASR_STATE_PACKET, 282 ASR_STATE_SUBQUERY, 283 ASR_STATE_NOT_FOUND, 284 ASR_STATE_HALT, 285 }; 286 287 #define MAXPACKETSZ 4096 288 289 __BEGIN_HIDDEN_DECLS 290 291 /* asr_utils.c */ 292 void _asr_pack_init(struct asr_pack *, char *, size_t); 293 int _asr_pack_header(struct asr_pack *, const struct asr_dns_header *); 294 int _asr_pack_query(struct asr_pack *, uint16_t, uint16_t, const char *); 295 int _asr_pack_edns0(struct asr_pack *, uint16_t, int); 296 void _asr_unpack_init(struct asr_unpack *, const char *, size_t); 297 int _asr_unpack_header(struct asr_unpack *, struct asr_dns_header *); 298 int _asr_unpack_query(struct asr_unpack *, struct asr_dns_query *); 299 int _asr_unpack_rr(struct asr_unpack *, struct asr_dns_rr *); 300 int _asr_sockaddr_from_str(struct sockaddr *, int, const char *); 301 ssize_t _asr_dname_from_fqdn(const char *, char *, size_t); 302 ssize_t _asr_addr_as_fqdn(const char *, int, char *, size_t); 303 304 /* asr.c */ 305 void _asr_resolver_done(void *); 306 struct asr_ctx *_asr_use_resolver(void *); 307 struct asr_ctx *_asr_no_resolver(void); 308 void _asr_ctx_unref(struct asr_ctx *); 309 struct asr_query *_asr_async_new(struct asr_ctx *, int); 310 void _asr_async_free(struct asr_query *); 311 size_t _asr_make_fqdn(const char *, const char *, char *, size_t); 312 char *_asr_strdname(const char *, char *, size_t); 313 int _asr_iter_db(struct asr_query *); 314 int _asr_parse_namedb_line(FILE *, char **, int, char *, size_t); 315 316 /* *_async.c */ 317 struct asr_query *_res_query_async_ctx(const char *, int, int, struct asr_ctx *); 318 struct asr_query *_res_search_async_ctx(const char *, int, int, struct asr_ctx *); 319 struct asr_query *_gethostbyaddr_async_ctx(const void *, socklen_t, int, 320 struct asr_ctx *); 321 322 int _asr_iter_domain(struct asr_query *, const char *, char *, size_t); 323 324 #ifdef DEBUG 325 326 #define DPRINT(...) do { if(_asr_debug) { \ 327 fprintf(_asr_debug, __VA_ARGS__); \ 328 } } while (0) 329 #define DPRINT_PACKET(n, p, s) do { if(_asr_debug) { \ 330 fprintf(_asr_debug, "----- %s -----\n", n); \ 331 _asr_dump_packet(_asr_debug, (p), (s)); \ 332 fprintf(_asr_debug, "--------------\n"); \ 333 } } while (0) 334 335 #else /* DEBUG */ 336 337 #define DPRINT(...) 338 #define DPRINT_PACKET(...) 339 340 #endif /* DEBUG */ 341 342 const char *_asr_querystr(int); 343 const char *_asr_statestr(int); 344 const char *_asr_transitionstr(int); 345 const char *_asr_print_sockaddr(const struct sockaddr *, char *, size_t); 346 void _asr_dump_config(FILE *, struct asr *); 347 void _asr_dump_packet(FILE *, const void *, size_t); 348 349 extern FILE *_asr_debug; 350 351 #define async_set_state(a, s) do { \ 352 DPRINT("asr: [%s@%p] %s -> %s\n", \ 353 _asr_querystr((a)->as_type), \ 354 as, \ 355 _asr_statestr((a)->as_state), \ 356 _asr_statestr((s))); \ 357 (a)->as_state = (s); } while (0) 358 359 __END_HIDDEN_DECLS 360