1 /* $OpenBSD: asr_private.h,v 1.49 2023/11/20 12:15:16 florian 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 (0x1 << 6) 27 #define AD_MASK (0x1 << 5) 28 #define CD_MASK (0x1 << 4) 29 #define RCODE_MASK (0xf) 30 31 #define OPCODE(v) ((v) & OPCODE_MASK) 32 #define RCODE(v) ((v) & RCODE_MASK) 33 34 35 struct asr_pack { 36 char *buf; 37 size_t len; 38 size_t offset; 39 int err; 40 }; 41 42 struct asr_unpack { 43 const char *buf; 44 size_t len; 45 size_t offset; 46 int err; 47 }; 48 49 struct asr_dns_header { 50 uint16_t id; 51 uint16_t flags; 52 uint16_t qdcount; 53 uint16_t ancount; 54 uint16_t nscount; 55 uint16_t arcount; 56 }; 57 58 struct asr_dns_query { 59 char q_dname[MAXDNAME]; 60 uint16_t q_type; 61 uint16_t q_class; 62 }; 63 64 struct asr_dns_rr { 65 char rr_dname[MAXDNAME]; 66 uint16_t rr_type; 67 uint16_t rr_class; 68 uint32_t rr_ttl; 69 union { 70 struct { 71 char cname[MAXDNAME]; 72 } cname; 73 struct { 74 uint16_t preference; 75 char exchange[MAXDNAME]; 76 } mx; 77 struct { 78 char nsname[MAXDNAME]; 79 } ns; 80 struct { 81 char ptrname[MAXDNAME]; 82 } ptr; 83 struct { 84 char mname[MAXDNAME]; 85 char rname[MAXDNAME]; 86 uint32_t serial; 87 uint32_t refresh; 88 uint32_t retry; 89 uint32_t expire; 90 uint32_t minimum; 91 } soa; 92 struct { 93 struct in_addr addr; 94 } in_a; 95 struct { 96 struct in6_addr addr6; 97 } in_aaaa; 98 struct { 99 uint16_t rdlen; 100 const void *rdata; 101 } other; 102 } rr; 103 }; 104 105 106 #define ASR_MAXNS 5 107 #define ASR_MAXDB 3 108 #define ASR_MAXDOM 10 109 110 enum async_type { 111 ASR_SEND, 112 ASR_SEARCH, 113 ASR_GETRRSETBYNAME, 114 ASR_GETHOSTBYNAME, 115 ASR_GETHOSTBYADDR, 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_GETNET 0x00001000 160 #define ASYNC_EXTOBUF 0x00002000 161 162 #define ASYNC_NO_INET 0x00010000 163 #define ASYNC_NO_INET6 0x00020000 164 165 struct asr_query { 166 int (*as_run)(struct asr_query *, struct asr_result *); 167 struct asr_ctx *as_ctx; 168 int as_type; 169 int as_flags; 170 int as_state; 171 172 /* cond */ 173 int as_timeout; 174 int as_fd; 175 struct asr_query *as_subq; 176 177 /* loop indices in ctx */ 178 int as_dom_step; 179 int as_dom_idx; 180 int as_dom_flags; 181 int as_family_idx; 182 int as_db_idx; 183 184 int as_count; 185 186 union { 187 struct { 188 uint16_t reqid; 189 int class; 190 int type; 191 char *dname; /* not fqdn! */ 192 int rcode; /* response code */ 193 int ancount; /* answer count */ 194 195 int nsidx; 196 int nsloop; 197 198 /* io buffers for query/response */ 199 unsigned char *obuf; 200 size_t obuflen; 201 size_t obufsize; 202 unsigned char *ibuf; 203 size_t ibuflen; 204 size_t ibufsize; 205 size_t datalen; /* for tcp io */ 206 uint16_t pktlen; 207 } dns; 208 209 struct { 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 *hostname; 233 char *servname; 234 int port_tcp; 235 int port_udp; 236 union { 237 struct sockaddr sa; 238 struct sockaddr_in sain; 239 struct sockaddr_in6 sain6; 240 } sa; 241 242 struct addrinfo hints; 243 char *fqdn; 244 struct addrinfo *aifirst; 245 struct addrinfo *ailast; 246 } ai; 247 248 struct { 249 char *hostname; 250 char *servname; 251 size_t hostnamelen; 252 size_t servnamelen; 253 union { 254 struct sockaddr sa; 255 struct sockaddr_in sain; 256 struct sockaddr_in6 sain6; 257 } sa; 258 int flags; 259 } ni; 260 #define MAXTOKEN 10 261 } as; 262 263 }; 264 265 #define AS_DB(p) ((p)->as_ctx->ac_db[(p)->as_db_idx - 1]) 266 #define AS_FAMILY(p) ((p)->as_ctx->ac_family[(p)->as_family_idx]) 267 268 enum asr_state { 269 ASR_STATE_INIT, 270 ASR_STATE_NEXT_DOMAIN, 271 ASR_STATE_NEXT_DB, 272 ASR_STATE_SAME_DB, 273 ASR_STATE_NEXT_FAMILY, 274 ASR_STATE_NEXT_NS, 275 ASR_STATE_UDP_SEND, 276 ASR_STATE_UDP_RECV, 277 ASR_STATE_TCP_WRITE, 278 ASR_STATE_TCP_READ, 279 ASR_STATE_PACKET, 280 ASR_STATE_SUBQUERY, 281 ASR_STATE_NOT_FOUND, 282 ASR_STATE_HALT, 283 }; 284 285 #define MAXPACKETSZ 4096 286 287 __BEGIN_HIDDEN_DECLS 288 289 /* asr_utils.c */ 290 void _asr_pack_init(struct asr_pack *, char *, size_t); 291 int _asr_pack_header(struct asr_pack *, const struct asr_dns_header *); 292 int _asr_pack_query(struct asr_pack *, uint16_t, uint16_t, const char *); 293 int _asr_pack_edns0(struct asr_pack *, uint16_t, int); 294 void _asr_unpack_init(struct asr_unpack *, const char *, size_t); 295 int _asr_unpack_header(struct asr_unpack *, struct asr_dns_header *); 296 int _asr_unpack_query(struct asr_unpack *, struct asr_dns_query *); 297 int _asr_unpack_rr(struct asr_unpack *, struct asr_dns_rr *); 298 int _asr_sockaddr_from_str(struct sockaddr *, int, const char *); 299 ssize_t _asr_dname_from_fqdn(const char *, char *, size_t); 300 ssize_t _asr_addr_as_fqdn(const char *, int, char *, size_t); 301 int hnok_lenient(const char *); 302 int _asr_is_localhost(const char*); 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