gio/gthreadedresolver.c

   1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
   2
   3 /* GIO - GLib Input, Output and Streaming Library
   4  *
   5  * Copyright (C) 2008 Red Hat, Inc.
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General
  18  * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "config.h"
  22 #include <glib.h>
  23 #include "glibintl.h"
  24
  25 #include <stdio.h>
  26 #include <string.h>
  27
  28 #include "gthreadedresolver.h"
  29 #include "gnetworkingprivate.h"
  30
  31 #include "gcancellable.h"
  32 #include "ginetaddress.h"
  33 #include "ginetsocketaddress.h"
  34 #include "gtask.h"
  35 #include "gsocketaddress.h"
  36 #include "gsrvtarget.h"
  37
  38
  39 G_DEFINE_TYPE (GThreadedResolver, g_threaded_resolver, G_TYPE_RESOLVER)
  40
  41 static void
  42 g_threaded_resolver_init (GThreadedResolver *gtr)
  43 {
  44 }
  45
  46 static GResolverError
  47 g_resolver_error_from_addrinfo_error (gint err)
  48 {
  49   switch (err)
  50     {
  51     case EAI_FAIL:
  52 #if defined(EAI_NODATA) && (EAI_NODATA != EAI_NONAME)
  53     case EAI_NODATA:
  54 #endif
  55     case EAI_NONAME:
  56       return G_RESOLVER_ERROR_NOT_FOUND;
  57
  58     case EAI_AGAIN:
  59       return G_RESOLVER_ERROR_TEMPORARY_FAILURE;
  60
  61     default:
  62       return G_RESOLVER_ERROR_INTERNAL;
  63     }
  64 }
  65
  66 static struct addrinfo addrinfo_hints;
  67
  68 static void
  69 do_lookup_by_name (GTask         *task,
  70                    gpointer       source_object,
  71                    gpointer       task_data,
  72                    GCancellable  *cancellable)
  73 {
  74   const char *hostname = task_data;
  75   struct addrinfo *res = NULL;
  76   GList *addresses;
  77   gint retval;
  78
  79   retval = getaddrinfo (hostname, NULL, &addrinfo_hints, &res);
  80
  81   if (retval == 0)
  82     {
  83       struct addrinfo *ai;
  84       GSocketAddress *sockaddr;
  85       GInetAddress *addr;
  86
  87       addresses = NULL;
  88       for (ai = res; ai; ai = ai->ai_next)
  89         {
  90           sockaddr = g_socket_address_new_from_native (ai->ai_addr, ai->ai_addrlen);
  91           if (!sockaddr)
  92             continue;
  93           if (!G_IS_INET_SOCKET_ADDRESS (sockaddr))
  94             {
  95               g_clear_object (&sockaddr);
  96               continue;
  97             }
  98
  99           addr = g_object_ref (g_inet_socket_address_get_address ((GInetSocketAddress *)sockaddr));
 100           addresses = g_list_prepend (addresses, addr);
 101           g_object_unref (sockaddr);
 102         }
 103
 104       if (addresses != NULL)
 105         {
 106           addresses = g_list_reverse (addresses);
 107           g_task_return_pointer (task, addresses,
 108                                  (GDestroyNotify)g_resolver_free_addresses);
 109         }
 110       else
 111         {
 112           /* All addresses failed to be converted to GSocketAddresses. */
 113           g_task_return_new_error (task,
 114                                    G_RESOLVER_ERROR,
 115                                    G_RESOLVER_ERROR_NOT_FOUND,
 116                                    _("Error resolving '%s': %s"),
 117                                    hostname,
 118                                    _("No valid addresses were found"));
 119         }
 120     }
 121   else
 122     {
 123       g_task_return_new_error (task,
 124                                G_RESOLVER_ERROR,
 125                                g_resolver_error_from_addrinfo_error (retval),
 126                                _("Error resolving '%s': %s"),
 127                                hostname, gai_strerror (retval));
 128     }
 129
 130   if (res)
 131     freeaddrinfo (res);
 132 }
 133
 134 static GList *
 135 lookup_by_name (GResolver     *resolver,
 136                 const gchar   *hostname,
 137                 GCancellable  *cancellable,
 138                 GError       **error)
 139 {
 140   GTask *task;
 141   GList *addresses;
 142
 143   task = g_task_new (resolver, cancellable, NULL, NULL);
 144   g_task_set_task_data (task, g_strdup (hostname), g_free);
 145   g_task_set_return_on_cancel (task, TRUE);
 146   g_task_run_in_thread_sync (task, do_lookup_by_name);
 147   addresses = g_task_propagate_pointer (task, error);
 148   g_object_unref (task);
 149
 150   return addresses;
 151 }
 152
 153 static void
 154 lookup_by_name_async (GResolver           *resolver,
 155                       const gchar         *hostname,
 156                       GCancellable        *cancellable,
 157                       GAsyncReadyCallback  callback,
 158                       gpointer             user_data)
 159 {
 160   GTask *task;
 161
 162   task = g_task_new (resolver, cancellable, callback, user_data);
 163   g_task_set_task_data (task, g_strdup (hostname), g_free);
 164   g_task_set_return_on_cancel (task, TRUE);
 165   g_task_run_in_thread (task, do_lookup_by_name);
 166   g_object_unref (task);
 167 }
 168
 169 static GList *
 170 lookup_by_name_finish (GResolver     *resolver,
 171                        GAsyncResult  *result,
 172                        GError       **error)
 173 {
 174   g_return_val_if_fail (g_task_is_valid (result, resolver), NULL);
 175
 176   return g_task_propagate_pointer (G_TASK (result), error);
 177 }
 178
 179
 180 static void
 181 do_lookup_by_address (GTask         *task,
 182                       gpointer       source_object,
 183                       gpointer       task_data,
 184                       GCancellable  *cancellable)
 185 {
 186   GInetAddress *address = task_data;
 187   struct sockaddr_storage sockaddr;
 188   gsize sockaddr_size;
 189   GSocketAddress *gsockaddr;
 190   gchar name[NI_MAXHOST];
 191   gint retval;
 192
 193   gsockaddr = g_inet_socket_address_new (address, 0);
 194   g_socket_address_to_native (gsockaddr, (struct sockaddr *)&sockaddr,
 195                               sizeof (sockaddr), NULL);
 196   sockaddr_size = g_socket_address_get_native_size (gsockaddr);
 197   g_object_unref (gsockaddr);
 198
 199   retval = getnameinfo ((struct sockaddr *)&sockaddr, sockaddr_size,
 200                         name, sizeof (name), NULL, 0, NI_NAMEREQD);
 201   if (retval == 0)
 202     g_task_return_pointer (task, g_strdup (name), g_free);
 203   else
 204     {
 205       gchar *phys;
 206
 207       phys = g_inet_address_to_string (address);
 208       g_task_return_new_error (task,
 209                                G_RESOLVER_ERROR,
 210                                g_resolver_error_from_addrinfo_error (retval),
 211                                _("Error reverse-resolving '%s': %s"),
 212                                phys ? phys : "(unknown)",
 213                                gai_strerror (retval));
 214       g_free (phys);
 215     }
 216 }
 217
 218 static gchar *
 219 lookup_by_address (GResolver        *resolver,
 220                    GInetAddress     *address,
 221                    GCancellable     *cancellable,
 222                    GError          **error)
 223 {
 224   GTask *task;
 225   gchar *name;
 226
 227   task = g_task_new (resolver, cancellable, NULL, NULL);
 228   g_task_set_task_data (task, g_object_ref (address), g_object_unref);
 229   g_task_set_return_on_cancel (task, TRUE);
 230   g_task_run_in_thread_sync (task, do_lookup_by_address);
 231   name = g_task_propagate_pointer (task, error);
 232   g_object_unref (task);
 233
 234   return name;
 235 }
 236
 237 static void
 238 lookup_by_address_async (GResolver           *resolver,
 239                          GInetAddress        *address,
 240                          GCancellable        *cancellable,
 241                          GAsyncReadyCallback  callback,
 242                          gpointer             user_data)
 243 {
 244   GTask *task;
 245
 246   task = g_task_new (resolver, cancellable, callback, user_data);
 247   g_task_set_task_data (task, g_object_ref (address), g_object_unref);
 248   g_task_set_return_on_cancel (task, TRUE);
 249   g_task_run_in_thread (task, do_lookup_by_address);
 250   g_object_unref (task);
 251 }
 252
 253 static gchar *
 254 lookup_by_address_finish (GResolver     *resolver,
 255                           GAsyncResult  *result,
 256                           GError       **error)
 257 {
 258   g_return_val_if_fail (g_task_is_valid (result, resolver), NULL);
 259
 260   return g_task_propagate_pointer (G_TASK (result), error);
 261 }
 262
 263
 264 #if defined(G_OS_UNIX)
 265
 266 #ifdef __BIONIC__
 267 /* Copy from bionic/libc/private/arpa_nameser_compat.h
 268  * and bionic/libc/private/arpa_nameser.h */
 269 typedef struct {
 270         unsigned        id :16;         /* query identification number */
 271 #if BYTE_ORDER == BIG_ENDIAN
 272                         /* fields in third byte */
 273         unsigned        qr: 1;          /* response flag */
 274         unsigned        opcode: 4;      /* purpose of message */
 275         unsigned        aa: 1;          /* authoritive answer */
 276         unsigned        tc: 1;          /* truncated message */
 277         unsigned        rd: 1;          /* recursion desired */
 278                         /* fields in fourth byte */
 279         unsigned        ra: 1;          /* recursion available */
 280         unsigned        unused :1;      /* unused bits (MBZ as of 4.9.3a3) */
 281         unsigned        ad: 1;          /* authentic data from named */
 282         unsigned        cd: 1;          /* checking disabled by resolver */
 283         unsigned        rcode :4;       /* response code */
 284 #endif
 285 #if BYTE_ORDER == LITTLE_ENDIAN || BYTE_ORDER == PDP_ENDIAN
 286                         /* fields in third byte */
 287         unsigned        rd :1;          /* recursion desired */
 288         unsigned        tc :1;          /* truncated message */
 289         unsigned        aa :1;          /* authoritive answer */
 290         unsigned        opcode :4;      /* purpose of message */
 291         unsigned        qr :1;          /* response flag */
 292                         /* fields in fourth byte */
 293         unsigned        rcode :4;       /* response code */
 294         unsigned        cd: 1;          /* checking disabled by resolver */
 295         unsigned        ad: 1;          /* authentic data from named */
 296         unsigned        unused :1;      /* unused bits (MBZ as of 4.9.3a3) */
 297         unsigned        ra :1;          /* recursion available */
 298 #endif
 299                         /* remaining bytes */
 300         unsigned        qdcount :16;    /* number of question entries */
 301         unsigned        ancount :16;    /* number of answer entries */
 302         unsigned        nscount :16;    /* number of authority entries */
 303         unsigned        arcount :16;    /* number of resource entries */
 304 } HEADER;
 305
 306 #define NS_INT32SZ      4       /* #/bytes of data in a uint32_t */
 307 #define NS_INT16SZ      2       /* #/bytes of data in a uint16_t */
 308
 309 #define NS_GET16(s, cp) do { \
 310         const u_char *t_cp = (const u_char *)(cp); \
 311         (s) = ((uint16_t)t_cp[0] << 8) \
 312             | ((uint16_t)t_cp[1]) \
 313             ; \
 314         (cp) += NS_INT16SZ; \
 315 } while (/*CONSTCOND*/0)
 316
 317 #define NS_GET32(l, cp) do { \
 318         const u_char *t_cp = (const u_char *)(cp); \
 319         (l) = ((uint32_t)t_cp[0] << 24) \
 320             | ((uint32_t)t_cp[1] << 16) \
 321             | ((uint32_t)t_cp[2] << 8) \
 322             | ((uint32_t)t_cp[3]) \
 323             ; \
 324         (cp) += NS_INT32SZ; \
 325 } while (/*CONSTCOND*/0)
 326
 327 #define GETSHORT                NS_GET16
 328 #define GETLONG                 NS_GET32
 329
 330 #define C_IN 1
 331
 332 /* From bionic/libc/private/resolv_private.h */
 333 int dn_expand(const u_char *, const u_char *, const u_char *, char *, int);
 334 #define dn_skipname __dn_skipname
 335 int dn_skipname(const u_char *, const u_char *);
 336
 337 /* From bionic/libc/private/arpa_nameser_compat.h */
 338 #define T_MX            ns_t_mx
 339 #define T_TXT           ns_t_txt
 340 #define T_SOA           ns_t_soa
 341 #define T_NS            ns_t_ns
 342
 343 /* From bionic/libc/private/arpa_nameser.h */
 344 typedef enum __ns_type {
 345         ns_t_invalid = 0,       /* Cookie. */
 346         ns_t_a = 1,             /* Host address. */
 347         ns_t_ns = 2,            /* Authoritative server. */
 348         ns_t_md = 3,            /* Mail destination. */
 349         ns_t_mf = 4,            /* Mail forwarder. */
 350         ns_t_cname = 5,         /* Canonical name. */
 351         ns_t_soa = 6,           /* Start of authority zone. */
 352         ns_t_mb = 7,            /* Mailbox domain name. */
 353         ns_t_mg = 8,            /* Mail group member. */
 354         ns_t_mr = 9,            /* Mail rename name. */
 355         ns_t_null = 10,         /* Null resource record. */
 356         ns_t_wks = 11,          /* Well known service. */
 357         ns_t_ptr = 12,          /* Domain name pointer. */
 358         ns_t_hinfo = 13,        /* Host information. */
 359         ns_t_minfo = 14,        /* Mailbox information. */
 360         ns_t_mx = 15,           /* Mail routing information. */
 361         ns_t_txt = 16,          /* Text strings. */
 362         ns_t_rp = 17,           /* Responsible person. */
 363         ns_t_afsdb = 18,        /* AFS cell database. */
 364         ns_t_x25 = 19,          /* X_25 calling address. */
 365         ns_t_isdn = 20,         /* ISDN calling address. */
 366         ns_t_rt = 21,           /* Router. */
 367         ns_t_nsap = 22,         /* NSAP address. */
 368         ns_t_nsap_ptr = 23,     /* Reverse NSAP lookup (deprecated). */
 369         ns_t_sig = 24,          /* Security signature. */
 370         ns_t_key = 25,          /* Security key. */
 371         ns_t_px = 26,           /* X.400 mail mapping. */
 372         ns_t_gpos = 27,         /* Geographical position (withdrawn). */
 373         ns_t_aaaa = 28,         /* Ip6 Address. */
 374         ns_t_loc = 29,          /* Location Information. */
 375         ns_t_nxt = 30,          /* Next domain (security). */
 376         ns_t_eid = 31,          /* Endpoint identifier. */
 377         ns_t_nimloc = 32,       /* Nimrod Locator. */
 378         ns_t_srv = 33,          /* Server Selection. */
 379         ns_t_atma = 34,         /* ATM Address */
 380         ns_t_naptr = 35,        /* Naming Authority PoinTeR */
 381         ns_t_kx = 36,           /* Key Exchange */
 382         ns_t_cert = 37,         /* Certification record */
 383         ns_t_a6 = 38,           /* IPv6 address (deprecates AAAA) */
 384         ns_t_dname = 39,        /* Non-terminal DNAME (for IPv6) */
 385         ns_t_sink = 40,         /* Kitchen sink (experimentatl) */
 386         ns_t_opt = 41,          /* EDNS0 option (meta-RR) */
 387         ns_t_apl = 42,          /* Address prefix list (RFC 3123) */
 388         ns_t_tkey = 249,        /* Transaction key */
 389         ns_t_tsig = 250,        /* Transaction signature. */
 390         ns_t_ixfr = 251,        /* Incremental zone transfer. */
 391         ns_t_axfr = 252,        /* Transfer zone of authority. */
 392         ns_t_mailb = 253,       /* Transfer mailbox records. */
 393         ns_t_maila = 254,       /* Transfer mail agent records. */
 394         ns_t_any = 255,         /* Wildcard match. */
 395         ns_t_zxfr = 256,        /* BIND-specific, nonstandard. */
 396         ns_t_max = 65536
 397 } ns_type;
 398
 399 #endif /* __BIONIC__ */
 400
 401 static GVariant *
 402 parse_res_srv (guchar  *answer,
 403                guchar  *end,
 404                guchar **p)
 405 {
 406   gchar namebuf[1024];
 407   guint16 priority, weight, port;
 408
 409   GETSHORT (priority, *p);
 410   GETSHORT (weight, *p);
 411   GETSHORT (port, *p);
 412   *p += dn_expand (answer, end, *p, namebuf, sizeof (namebuf));
 413
 414   return g_variant_new ("(qqqs)",
 415                         priority,
 416                         weight,
 417                         port,
 418                         namebuf);
 419 }
 420
 421 static GVariant *
 422 parse_res_soa (guchar  *answer,
 423                guchar  *end,
 424                guchar **p)
 425 {
 426   gchar mnamebuf[1024];
 427   gchar rnamebuf[1024];
 428   guint32 serial, refresh, retry, expire, ttl;
 429
 430   *p += dn_expand (answer, end, *p, mnamebuf, sizeof (mnamebuf));
 431   *p += dn_expand (answer, end, *p, rnamebuf, sizeof (rnamebuf));
 432
 433   GETLONG (serial, *p);
 434   GETLONG (refresh, *p);
 435   GETLONG (retry, *p);
 436   GETLONG (expire, *p);
 437   GETLONG (ttl, *p);
 438
 439   return g_variant_new ("(ssuuuuu)",
 440                         mnamebuf,
 441                         rnamebuf,
 442                         serial,
 443                         refresh,
 444                         retry,
 445                         expire,
 446                         ttl);
 447 }
 448
 449 static GVariant *
 450 parse_res_ns (guchar  *answer,
 451               guchar  *end,
 452               guchar **p)
 453 {
 454   gchar namebuf[1024];
 455
 456   *p += dn_expand (answer, end, *p, namebuf, sizeof (namebuf));
 457
 458   return g_variant_new ("(s)", namebuf);
 459 }
 460
 461 static GVariant *
 462 parse_res_mx (guchar  *answer,
 463               guchar  *end,
 464               guchar **p)
 465 {
 466   gchar namebuf[1024];
 467   guint16 preference;
 468
 469   GETSHORT (preference, *p);
 470
 471   *p += dn_expand (answer, end, *p, namebuf, sizeof (namebuf));
 472
 473   return g_variant_new ("(qs)",
 474                         preference,
 475                         namebuf);
 476 }
 477
 478 static GVariant *
 479 parse_res_txt (guchar  *answer,
 480                guchar  *end,
 481                guchar **p)
 482 {
 483   GVariant *record;
 484   GPtrArray *array;
 485   guchar *at = *p;
 486   gsize len;
 487
 488   array = g_ptr_array_new_with_free_func (g_free);
 489   while (at < end)
 490     {
 491       len = *(at++);
 492       if (len > at - end)
 493         break;
 494       g_ptr_array_add (array, g_strndup ((gchar *)at, len));
 495       at += len;
 496     }
 497
 498   *p = at;
 499   record = g_variant_new ("(@as)",
 500                           g_variant_new_strv ((const gchar **)array->pdata, array->len));
 501   g_ptr_array_free (array, TRUE);
 502   return record;
 503 }
 504
 505 static gint
 506 g_resolver_record_type_to_rrtype (GResolverRecordType type)
 507 {
 508   switch (type)
 509   {
 510     case G_RESOLVER_RECORD_SRV:
 511       return T_SRV;
 512     case G_RESOLVER_RECORD_TXT:
 513       return T_TXT;
 514     case G_RESOLVER_RECORD_SOA:
 515       return T_SOA;
 516     case G_RESOLVER_RECORD_NS:
 517       return T_NS;
 518     case G_RESOLVER_RECORD_MX:
 519       return T_MX;
 520   }
 521   g_return_val_if_reached (-1);
 522 }
 523
 524 static GList *
 525 g_resolver_records_from_res_query (const gchar      *rrname,
 526                                    gint              rrtype,
 527                                    guchar           *answer,
 528                                    gint              len,
 529                                    gint              herr,
 530                                    GError          **error)
 531 {
 532   gint count;
 533   gchar namebuf[1024];
 534   guchar *end, *p;
 535   guint16 type, qclass, rdlength;
 536   guint32 ttl;
 537   HEADER *header;
 538   GList *records;
 539   GVariant *record;
 540
 541   if (len <= 0)
 542     {
 543       if (len == 0 || herr == HOST_NOT_FOUND || herr == NO_DATA)
 544         {
 545           g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_NOT_FOUND,
 546                        _("No DNS record of the requested type for '%s'"), rrname);
 547         }
 548       else if (herr == TRY_AGAIN)
 549         {
 550           g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_TEMPORARY_FAILURE,
 551                        _("Temporarily unable to resolve '%s'"), rrname);
 552         }
 553       else
 554         {
 555           g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
 556                        _("Error resolving '%s'"), rrname);
 557         }
 558
 559       return NULL;
 560     }
 561
 562   records = NULL;
 563
 564   header = (HEADER *)answer;
 565   p = answer + sizeof (HEADER);
 566   end = answer + len;
 567
 568   /* Skip query */
 569   count = ntohs (header->qdcount);
 570   while (count-- && p < end)
 571     {
 572       p += dn_expand (answer, end, p, namebuf, sizeof (namebuf));
 573       p += 4;
 574
 575       /* To silence gcc warnings */
 576       namebuf[0] = namebuf[1];
 577     }
 578
 579   /* Read answers */
 580   count = ntohs (header->ancount);
 581   while (count-- && p < end)
 582     {
 583       p += dn_expand (answer, end, p, namebuf, sizeof (namebuf));
 584       GETSHORT (type, p);
 585       GETSHORT (qclass, p);
 586       GETLONG  (ttl, p);
 587       ttl = ttl; /* To avoid -Wunused-but-set-variable */
 588       GETSHORT (rdlength, p);
 589
 590       if (type != rrtype || qclass != C_IN)
 591         {
 592           p += rdlength;
 593           continue;
 594         }
 595
 596       switch (rrtype)
 597         {
 598         case T_SRV:
 599           record = parse_res_srv (answer, end, &p);
 600           break;
 601         case T_MX:
 602           record = parse_res_mx (answer, end, &p);
 603           break;
 604         case T_SOA:
 605           record = parse_res_soa (answer, end, &p);
 606           break;
 607         case T_NS:
 608           record = parse_res_ns (answer, end, &p);
 609           break;
 610         case T_TXT:
 611           record = parse_res_txt (answer, p + rdlength, &p);
 612           break;
 613         default:
 614           g_warn_if_reached ();
 615           record = NULL;
 616           break;
 617         }
 618
 619       if (record != NULL)
 620         records = g_list_prepend (records, record);
 621     }
 622
 623   if (records == NULL)
 624     {
 625       g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_NOT_FOUND,
 626                    _("No DNS record of the requested type for '%s'"), rrname);
 627
 628       return NULL;
 629     }
 630   else
 631     return records;
 632 }
 633
 634 #elif defined(G_OS_WIN32)
 635
 636 static GVariant *
 637 parse_dns_srv (DNS_RECORD *rec)
 638 {
 639   return g_variant_new ("(qqqs)",
 640                         (guint16)rec->Data.SRV.wPriority,
 641                         (guint16)rec->Data.SRV.wWeight,
 642                         (guint16)rec->Data.SRV.wPort,
 643                         rec->Data.SRV.pNameTarget);
 644 }
 645
 646 static GVariant *
 647 parse_dns_soa (DNS_RECORD *rec)
 648 {
 649   return g_variant_new ("(ssuuuuu)",
 650                         rec->Data.SOA.pNamePrimaryServer,
 651                         rec->Data.SOA.pNameAdministrator,
 652                         (guint32)rec->Data.SOA.dwSerialNo,
 653                         (guint32)rec->Data.SOA.dwRefresh,
 654                         (guint32)rec->Data.SOA.dwRetry,
 655                         (guint32)rec->Data.SOA.dwExpire,
 656                         (guint32)rec->Data.SOA.dwDefaultTtl);
 657 }
 658
 659 static GVariant *
 660 parse_dns_ns (DNS_RECORD *rec)
 661 {
 662   return g_variant_new ("(s)", rec->Data.NS.pNameHost);
 663 }
 664
 665 static GVariant *
 666 parse_dns_mx (DNS_RECORD *rec)
 667 {
 668   return g_variant_new ("(qs)",
 669                         (guint16)rec->Data.MX.wPreference,
 670                         rec->Data.MX.pNameExchange);
 671 }
 672
 673 static GVariant *
 674 parse_dns_txt (DNS_RECORD *rec)
 675 {
 676   GVariant *record;
 677   GPtrArray *array;
 678   DWORD i;
 679
 680   array = g_ptr_array_new ();
 681   for (i = 0; i < rec->Data.TXT.dwStringCount; i++)
 682     g_ptr_array_add (array, rec->Data.TXT.pStringArray[i]);
 683   record = g_variant_new ("(@as)",
 684                           g_variant_new_strv ((const gchar **)array->pdata, array->len));
 685   g_ptr_array_free (array, TRUE);
 686   return record;
 687 }
 688
 689 static WORD
 690 g_resolver_record_type_to_dnstype (GResolverRecordType type)
 691 {
 692   switch (type)
 693   {
 694     case G_RESOLVER_RECORD_SRV:
 695       return DNS_TYPE_SRV;
 696     case G_RESOLVER_RECORD_TXT:
 697       return DNS_TYPE_TEXT;
 698     case G_RESOLVER_RECORD_SOA:
 699       return DNS_TYPE_SOA;
 700     case G_RESOLVER_RECORD_NS:
 701       return DNS_TYPE_NS;
 702     case G_RESOLVER_RECORD_MX:
 703       return DNS_TYPE_MX;
 704   }
 705   g_return_val_if_reached (-1);
 706 }
 707
 708 static GList *
 709 g_resolver_records_from_DnsQuery (const gchar  *rrname,
 710                                   WORD          dnstype,
 711                                   DNS_STATUS    status,
 712                                   DNS_RECORD   *results,
 713                                   GError      **error)
 714 {
 715   DNS_RECORD *rec;
 716   gpointer record;
 717   GList *records;
 718
 719   if (status != ERROR_SUCCESS)
 720     {
 721       if (status == DNS_ERROR_RCODE_NAME_ERROR)
 722         {
 723           g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_NOT_FOUND,
 724                        _("No DNS record of the requested type for '%s'"), rrname);
 725         }
 726       else if (status == DNS_ERROR_RCODE_SERVER_FAILURE)
 727         {
 728           g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_TEMPORARY_FAILURE,
 729                        _("Temporarily unable to resolve '%s'"), rrname);
 730         }
 731       else
 732         {
 733           g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
 734                        _("Error resolving '%s'"), rrname);
 735         }
 736
 737       return NULL;
 738     }
 739
 740   records = NULL;
 741   for (rec = results; rec; rec = rec->pNext)
 742     {
 743       if (rec->wType != dnstype)
 744         continue;
 745       switch (dnstype)
 746         {
 747         case DNS_TYPE_SRV:
 748           record = parse_dns_srv (rec);
 749           break;
 750         case DNS_TYPE_SOA:
 751           record = parse_dns_soa (rec);
 752           break;
 753         case DNS_TYPE_NS:
 754           record = parse_dns_ns (rec);
 755           break;
 756         case DNS_TYPE_MX:
 757           record = parse_dns_mx (rec);
 758           break;
 759         case DNS_TYPE_TEXT:
 760           record = parse_dns_txt (rec);
 761           break;
 762         default:
 763           g_warn_if_reached ();
 764           record = NULL;
 765           break;
 766         }
 767       if (record != NULL)
 768         records = g_list_prepend (records, g_variant_ref_sink (record));
 769     }
 770
 771   if (records == NULL)
 772     {
 773       g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_NOT_FOUND,
 774                    _("No DNS record of the requested type for '%s'"), rrname);
 775
 776       return NULL;
 777     }
 778   else
 779     return records;
 780 }
 781
 782 #endif
 783
 784 typedef struct {
 785   char *rrname;
 786   GResolverRecordType record_type;
 787 } LookupRecordsData;
 788
 789 static void
 790 free_lookup_records_data (LookupRecordsData *lrd)
 791 {
 792   g_free (lrd->rrname);
 793   g_slice_free (LookupRecordsData, lrd);
 794 }
 795
 796 static void
 797 free_records (GList *records)
 798 {
 799   g_list_free_full (records, (GDestroyNotify) g_variant_unref);
 800 }
 801
 802 #if defined(G_OS_UNIX)
 803 #ifdef __BIONIC__
 804 #define C_IN 1
 805 int res_query(const char *, int, int, u_char *, int);
 806 #endif
 807 #endif
 808
 809 static void
 810 do_lookup_records (GTask         *task,
 811                    gpointer       source_object,
 812                    gpointer       task_data,
 813                    GCancellable  *cancellable)
 814 {
 815   LookupRecordsData *lrd = task_data;
 816   GList *records;
 817   GError *error = NULL;
 818
 819 #if defined(G_OS_UNIX)
 820   gint len = 512;
 821   gint herr;
 822   GByteArray *answer;
 823   gint rrtype;
 824
 825   rrtype = g_resolver_record_type_to_rrtype (lrd->record_type);
 826   answer = g_byte_array_new ();
 827   for (;;)
 828     {
 829       g_byte_array_set_size (answer, len * 2);
 830       len = res_query (lrd->rrname, C_IN, rrtype, answer->data, answer->len);
 831
 832       /* If answer fit in the buffer then we're done */
 833       if (len < 0 || len < (gint)answer->len)
 834         break;
 835
 836       /*
 837        * On overflow some res_query's return the length needed, others
 838        * return the full length entered. This code works in either case.
 839        */
 840     }
 841
 842   herr = h_errno;
 843   records = g_resolver_records_from_res_query (lrd->rrname, rrtype, answer->data, len, herr, &error);
 844   g_byte_array_free (answer, TRUE);
 845
 846 #else
 847
 848   DNS_STATUS status;
 849   DNS_RECORD *results = NULL;
 850   WORD dnstype;
 851
 852   dnstype = g_resolver_record_type_to_dnstype (lrd->record_type);
 853   status = DnsQuery_A (lrd->rrname, dnstype, DNS_QUERY_STANDARD, NULL, &results, NULL);
 854   records = g_resolver_records_from_DnsQuery (lrd->rrname, dnstype, status, results, &error);
 855   if (results != NULL)
 856     DnsRecordListFree (results, DnsFreeRecordList);
 857
 858 #endif
 859
 860   if (records)
 861     g_task_return_pointer (task, records, (GDestroyNotify) free_records);
 862   else
 863     g_task_return_error (task, error);
 864 }
 865
 866 static GList *
 867 lookup_records (GResolver              *resolver,
 868                 const gchar            *rrname,
 869                 GResolverRecordType     record_type,
 870                 GCancellable           *cancellable,
 871                 GError                **error)
 872 {
 873   GTask *task;
 874   GList *records;
 875   LookupRecordsData *lrd;
 876
 877   task = g_task_new (resolver, cancellable, NULL, NULL);
 878
 879   lrd = g_slice_new (LookupRecordsData);
 880   lrd->rrname = g_strdup (rrname);
 881   lrd->record_type = record_type;
 882   g_task_set_task_data (task, lrd, (GDestroyNotify) free_lookup_records_data);
 883
 884   g_task_set_return_on_cancel (task, TRUE);
 885   g_task_run_in_thread_sync (task, do_lookup_records);
 886   records = g_task_propagate_pointer (task, error);
 887   g_object_unref (task);
 888
 889   return records;
 890 }
 891
 892 static void
 893 lookup_records_async (GResolver           *resolver,
 894                       const char          *rrname,
 895                       GResolverRecordType  record_type,
 896                       GCancellable        *cancellable,
 897                       GAsyncReadyCallback  callback,
 898                       gpointer             user_data)
 899 {
 900   GTask *task;
 901   LookupRecordsData *lrd;
 902
 903   task = g_task_new (resolver, cancellable, callback, user_data);
 904
 905   lrd = g_slice_new (LookupRecordsData);
 906   lrd->rrname = g_strdup (rrname);
 907   lrd->record_type = record_type;
 908   g_task_set_task_data (task, lrd, (GDestroyNotify) free_lookup_records_data);
 909
 910   g_task_set_return_on_cancel (task, TRUE);
 911   g_task_run_in_thread (task, do_lookup_records);
 912   g_object_unref (task);
 913 }
 914
 915 static GList *
 916 lookup_records_finish (GResolver     *resolver,
 917                        GAsyncResult  *result,
 918                        GError       **error)
 919 {
 920   g_return_val_if_fail (g_task_is_valid (result, resolver), NULL);
 921
 922   return g_task_propagate_pointer (G_TASK (result), error);
 923 }
 924
 925
 926 static void
 927 g_threaded_resolver_class_init (GThreadedResolverClass *threaded_class)
 928 {
 929   GResolverClass *resolver_class = G_RESOLVER_CLASS (threaded_class);
 930
 931   resolver_class->lookup_by_name           = lookup_by_name;
 932   resolver_class->lookup_by_name_async     = lookup_by_name_async;
 933   resolver_class->lookup_by_name_finish    = lookup_by_name_finish;
 934   resolver_class->lookup_by_address        = lookup_by_address;
 935   resolver_class->lookup_by_address_async  = lookup_by_address_async;
 936   resolver_class->lookup_by_address_finish = lookup_by_address_finish;
 937   resolver_class->lookup_records           = lookup_records;
 938   resolver_class->lookup_records_async     = lookup_records_async;
 939   resolver_class->lookup_records_finish    = lookup_records_finish;
 940
 941   /* Initialize addrinfo_hints */
 942 #ifdef AI_ADDRCONFIG
 943   addrinfo_hints.ai_flags |= AI_ADDRCONFIG;
 944 #endif
 945   /* These two don't actually matter, they just get copied into the
 946    * returned addrinfo structures (and then we ignore them). But if
 947    * we leave them unset, we'll get back duplicate answers.
 948    */
 949   addrinfo_hints.ai_socktype = SOCK_STREAM;
 950   addrinfo_hints.ai_protocol = IPPROTO_TCP;
 951 }