/*
* adns.h
- * - adns user-visible API (single-threaded, without any locking)
+ * - adns user-visible API
*/
/*
- * This file is part of adns, which is Copyright (C) 1997-1999 Ian Jackson
- *
+ *
+ * This file is
+ * Copyright (C) 1997-2000,2003,2006,2014 Ian Jackson
+ *
+ * It is part of adns, which is
+ * Copyright (C) 1997-2000,2003,2006,2014 Ian Jackson
+ * Copyright (C) 1999-2000,2003,2006 Tony Finch
+ * Copyright (C) 1991 Massachusetts Institute of Technology
+ *
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
+ * the Free Software Foundation; either version 3, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
+ *
+ *
+ * For the benefit of certain LGPL'd `omnibus' software which
+ * provides a uniform interface to various things including adns, I
+ * make the following additional licence. I do this because the GPL
+ * would otherwise force either the omnibus software to be GPL'd or
+ * the adns-using part to be distributed separately.
*
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software Foundation,
- * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * So: you may also redistribute and/or modify adns.h (but only the
+ * public header file adns.h and not any other part of adns) under the
+ * terms of the GNU Library General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * Note that adns itself is GPL'd. Authors of adns-using applications
+ * with GPL-incompatible licences, and people who distribute adns with
+ * applications where the whole distribution is not GPL'd, are still
+ * likely to be in violation of the GPL. Anyone who wants to do this
+ * should contact Ian Jackson. Please note that to avoid encouraging
+ * people to infringe the GPL as it applies to the body of adns, Ian
+ * thinks that if you take advantage of the special exception to
+ * redistribute just adns.h under the LGPL, you should retain this
+ * paragraph in its place in the appropriate copyright statements.
+ *
+ *
+ * You should have received a copy of the GNU General Public License,
+ * or the GNU Library General Public License, as appropriate, along
+ * with this program; if not, write to the Free Software Foundation.
*
- * $Id$
*/
#ifndef ADNS_H_INCLUDED
#define ADNS_H_INCLUDED
-#ifdef __cplusplus
-extern "C" { /* I really dislike this - iwj. */
-#endif
#include <stdio.h>
+#include <stdarg.h>
+#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
-#include <sys/types.h>
#include <sys/time.h>
#include <unistd.h>
+#include <net/if.h>
+
+#ifdef __cplusplus
+extern "C" { /* I really dislike this - iwj. */
+#endif
+
+/* Whether to support address families other than IPv4 in responses which use
+ * the `adns_rr_addr' structure. This is a source-compatibility issue: old
+ * clients may not expect to find address families other than AF_INET in
+ * their query results. There's a separate binary compatibility issue to do
+ * with the size of the `adns_rr_addr' structure, but we'll assume you can
+ * cope with that because you have this header file. Define
+ * `ADNS_FEATURE_IPV4ONLY' if you only want to see AF_INET addresses by
+ * default, or `ADNS_FEATURE_MANYAF' to allow multiple address families; the
+ * default is currently to stick with AF_INET only, but this is likely to
+ * change in a later release of ADNS. Note that any adns_qf_want_... flags
+ * in your query are observed: this setting affects only the default address
+ * families.
+ */
+#if !defined(ADNS_FEATURE_IPV4ONLY) && !defined(ADNS_FEATURE_MANYAF)
+# define ADNS_FEATURE_IPV4ONLY
+#elif defined(ADNS_FEATURE_IPV4ONLY) && defined(ADNS_FEATURE_MANYAF)
+# error "Feature flags ADNS_FEATURE_IPV4ONLY and ..._MANYAF are incompatible"
+#endif
/* All struct in_addr anywhere in adns are in NETWORK byte order. */
typedef struct adns__state *adns_state;
typedef struct adns__query *adns_query;
-typedef enum {
- adns_if_noenv= 0x0001, /* do not look at environment */
- adns_if_noerrprint= 0x0002, /* never print output to stderr (_debug overrides) */
- adns_if_noserverwarn= 0x0004, /* do not warn to stderr about duff nameservers etc */
- adns_if_debug= 0x0008, /* enable all output to stderr plus debug msgs */
- adns_if_noautosys= 0x0010, /* do not make syscalls at every opportunity */
- adns_if_eintr= 0x0020, /* allow _wait and _synchronous to return EINTR */
- adns_if_nosigpipe= 0x0040, /* applic has SIGPIPE set to SIG_IGN, do not protect */
- adns_if_checkc_entex= 0x0100, /* do consistency checks on entry/exit to adns funcs */
- adns_if_checkc_freq= 0x0300, /* do consistency checks very frequently (slow!) */
+typedef enum { /* In general, or together the desired flags: */
+ adns_if_none= 0x0000,/* no flags. nicer than 0 for some compilers */
+ adns_if_noenv= 0x0001,/* do not look at environment */
+ adns_if_noerrprint= 0x0002,/* never print to stderr (_debug overrides) */
+ adns_if_noserverwarn=0x0004,/* do not warn to stderr about duff servers etc */
+ adns_if_debug= 0x0008,/* enable all output to stderr plus debug msgs */
+ adns_if_logpid= 0x0080,/* include pid in diagnostic output */
+ adns_if_noautosys= 0x0010,/* do not make syscalls at every opportunity */
+ adns_if_eintr= 0x0020,/* allow _wait and _synchronous to return EINTR */
+ adns_if_nosigpipe= 0x0040,/* applic has SIGPIPE ignored, do not protect */
+ adns_if_checkc_entex=0x0100,/* consistency checks on entry/exit to adns fns */
+ adns_if_checkc_freq= 0x0300,/* consistency checks very frequently (slow!) */
+
+ adns_if_permit_ipv4= 0x0400,/* allow _addr queries to return IPv4 addresses */
+ adns_if_permit_ipv6= 0x0800,/* allow _addr queries to return IPv6 addresses */
+ adns_if_afmask= 0x0c00,
+ /* These are policy flags, and overridden by the adns_af:... option in
+ * resolv.conf. If the adns_qf_want_... query flags are incompatible with
+ * these settings (in the sense that no address families are permitted at
+ * all) then the query flags take precedence; otherwise only records which
+ * satisfy all of the stated requirements are allowed.
+ */
+ adns__if_sizeforce= 0x7fff,
} adns_initflags;
-typedef enum {
- adns_qf_search= 0x00000001, /* use the searchlist */
- adns_qf_usevc= 0x00000002, /* use a virtual circuit (TCP connection) */
- adns_qf_owner= 0x00000004, /* fill in the owner field in the answer */
- adns_qf_quoteok_query= 0x00000010, /* allow quote-requiring chars in query domain */
- adns_qf_quoteok_cname= 0x00000000, /* allow ... in CNAME we go via - now default */
- adns_qf_quoteok_anshost= 0x00000040, /* allow ... in things supposed to be hostnames */
- adns_qf_quotefail_cname= 0x00000080, /* refuse if quote-req chars in CNAME we go via */
- adns_qf_cname_loose= 0x00000100, /* allow refs to CNAMEs - without, get _s_cname */
- adns_qf_cname_forbid= 0x00000200, /* don't follow CNAMEs, instead give _s_cname */
- adns__qf_internalmask= 0x0ff00000
+typedef enum { /* In general, or together the desired flags: */
+ adns_qf_none= 0x00000000,/* no flags */
+ adns_qf_search= 0x00000001,/* use the searchlist */
+ adns_qf_usevc= 0x00000002,/* use a virtual circuit (TCP conn) */
+ adns_qf_owner= 0x00000004,/* fill in the owner field in the answer */
+ adns_qf_quoteok_query= 0x00000010,/* allow special chars in query domain */
+ adns_qf_quoteok_cname= 0x00000000,/* ... in CNAME we go via (now default) */
+ adns_qf_quoteok_anshost=0x00000040,/* ... in things supposedly hostnames */
+ adns_qf_quotefail_cname=0x00000080,/* refuse if quote-req chars in CNAME we go via */
+ adns_qf_cname_loose= 0x00000100,/* allow refs to CNAMEs - without, get _s_cname */
+ adns_qf_cname_strict= 0x00010000,/* forbid CNAME refs (default, currently) */
+ adns_qf_cname_forbid= 0x00000200,/* don't follow CNAMEs, instead give _s_cname */
+
+ adns_qf_want_ipv4= 0x00000400,/* try to return IPv4 addresses */
+ adns_qf_want_ipv6= 0x00000800,/* try to return IPv6 addresses */
+ adns_qf_want_allaf= 0x00000c00,/* all the above flag bits */
+ /* Without any of the _qf_want_... flags, _qtf_deref queries try to return
+ * all address families permitted by _if_permit_... (as overridden by the
+ * `adns_af:...' configuration option). Set flags to restrict the
+ * returned address families to the ones selected.
+ */
+ adns_qf_ipv6_mapv4= 0x00001000,/* ... return IPv4 addresses as v6-mapped */
+
+ adns_qf_addrlit_scope_forbid=0x00002000,/* forbid %<scope> in IPv6 literals */
+ adns_qf_addrlit_scope_numeric=0x00004000,/* %<scope> may only be numeric */
+ adns_qf_addrlit_ipv4_quadonly=0x00008000,/* reject non-dotted-quad ipv4 */
+
+ adns__qf_internalmask= 0x0ff00000,
+ adns__qf_sizeforce= 0x7fffffff
} adns_queryflags;
typedef enum {
- adns__rrt_typemask= 0x0ffff,
- adns__qtf_deref= 0x10000, /* dereference domains and perhaps produce extra data */
- adns__qtf_mail822= 0x20000, /* make mailboxes be in RFC822 rcpt field format */
-
- adns_r_none= 0,
-
- adns_r_a= 1,
-
- adns_r_ns_raw= 2,
- adns_r_ns= adns_r_ns_raw|adns__qtf_deref,
-
- adns_r_cname= 5,
-
- adns_r_soa_raw= 6,
- adns_r_soa= adns_r_soa_raw|adns__qtf_mail822,
-
- adns_r_ptr_raw= 12,
- adns_r_ptr= adns_r_ptr_raw|adns__qtf_deref,
-
- adns_r_hinfo= 13,
-
- adns_r_mx_raw= 15,
- adns_r_mx= adns_r_mx_raw|adns__qtf_deref,
-
- adns_r_txt= 16,
-
- adns_r_rp_raw= 17,
- adns_r_rp= adns_r_rp_raw|adns__qtf_mail822,
-
- adns_r_addr= adns_r_a|adns__qtf_deref
-
+ adns_rrt_typemask= 0x0ffff,
+ adns_rrt_reprmask= 0xffffff,
+ adns__qtf_deref_bit=0x10000,/* internal version of ..._deref below */
+ adns__qtf_mail822= 0x20000,/* return mailboxes in RFC822 rcpt field fmt */
+
+ adns__qtf_bigaddr=0x1000000,/* use the new larger sockaddr union */
+ adns__qtf_manyaf= 0x2000000,/* permitted to return multiple address families */
+
+ adns__qtf_deref= adns__qtf_deref_bit|adns__qtf_bigaddr
+#ifdef ADNS_FEATURE_MANYAF
+ |adns__qtf_manyaf
+#endif
+ ,/* dereference domains; perhaps get extra data */
+
+ adns_r_unknown= 0x40000,
+ /* To use this, ask for records of type <rr-type-code>|adns_r_unknown.
+ * adns will not process the RDATA - you'll get adns_rr_byteblocks,
+ * where the int is the length and the unsigned char* points to the
+ * data. String representation of the RR data (by adns_rrinfo) is as in
+ * RFC3597. adns_rr_info will not return the type name in *rrtname_r
+ * (due to memory management problems); *fmtname_r will be set to
+ * "unknown".
+ *
+ * Do not specify adns_r_unknown along with a known RR type which
+ * requires domain name uncompression (see RFC3597 s4); domain names
+ * will not be uncompressed and the resulting data would be useless.
+ * Asking for meta-RR types via adns_r_unknown will not work properly
+ * either and may make adns complain about server misbehaviour, so don't
+ * do that.
+ *
+ * Don't forget adns_qf_quoteok if that's what you want. */
+
+ adns_r_none= 0,
+
+ adns_r_a= 1,
+
+ adns_r_ns_raw= 2,
+ adns_r_ns= adns_r_ns_raw|adns__qtf_deref,
+
+ adns_r_cname= 5,
+
+ adns_r_soa_raw= 6,
+ adns_r_soa= adns_r_soa_raw|adns__qtf_mail822,
+
+ adns_r_ptr_raw= 12, /* do not mind PTR with wrong or missing addr */
+ adns_r_ptr= adns_r_ptr_raw|adns__qtf_deref,
+
+ adns_r_hinfo= 13,
+
+ adns_r_mx_raw= 15,
+ adns_r_mx= adns_r_mx_raw|adns__qtf_deref,
+
+ adns_r_txt= 16,
+
+ adns_r_rp_raw= 17,
+ adns_r_rp= adns_r_rp_raw|adns__qtf_mail822,
+
+ adns_r_aaaa= 28,
+
+ /* For SRV records, query domain without _qf_quoteok_query must look
+ * as expected from SRV RFC with hostname-like Name. _With_
+ * _quoteok_query, any query domain is allowed. */
+ adns_r_srv_raw= 33,
+ adns_r_srv= adns_r_srv_raw|adns__qtf_deref,
+
+ adns_r_addr= adns_r_a|adns__qtf_deref,
+
+ adns__rrt_sizeforce= 0x7fffffff,
+
} adns_rrtype;
/*
* In queries _with_ qf_quoteok_*, domains in the query or response
* may contain any characters, quoted according to RFC1035 5.1. On
* input to adns, the char* is a pointer to the interior of a "
- * delimited string, except that " may appear in it, and on output,
- * the char* is a pointer to a string which would be legal either
- * inside or outside " delimiters, and any characters not usually
- * legal in domain names will be quoted as \X (if the character is
- * 33-126 except \ and ") or \DDD.
+ * delimited string, except that " may appear in it unquoted. On
+ * output, the char* is a pointer to a string which would be legal
+ * either inside or outside " delimiters; any character which isn't
+ * legal in a hostname (ie alphanumeric or hyphen) or one of _ / +
+ * (the three other punctuation characters commonly abused in domain
+ * names) will be quoted, as \X if it is a printing ASCII character or
+ * \DDD otherwise.
*
* If the query goes via a CNAME then the canonical name (ie, the
* thing that the CNAME record refers to) is usually allowed to
* header field. The particular format used is that if the mailbox
* requires quoting according to the rules in RFC822 then the
* local-part is quoted in double quotes, which end at the next
- * unescaped double quote. (\ is the escape char, and is doubled, and
- * is used to escape only \ and ".) Otherwise the local-part is
- * presented as-is. In any case this is followed by an @ and the
- * domain. The domain will not contain any characters not legal in
- * hostnames. adns will protect the application from local parts
- * containing control characters - these appear to be legal according
- * to RFC822 but are clearly a bad idea.
+ * unescaped double quote (\ is the escape char, and is doubled, and
+ * is used to escape only \ and "). If the local-part is legal
+ * without quoting according to RFC822, it is presented as-is. In any
+ * case the local-part is followed by an @ and the domain. The domain
+ * will not contain any characters not legal in hostnames.
+ *
+ * Unquoted local-parts may contain any printing 7-bit ASCII
+ * except the punctuation characters ( ) < > @ , ; : \ " [ ]
+ * I.e. they may contain alphanumerics, and the following
+ * punctuation characters: ! # % ^ & * - _ = + { } .
+ *
+ * adns will reject local parts containing control characters (byte
+ * values 0-31, 127-159, and 255) - these appear to be legal according
+ * to RFC822 (at least 0-127) but are clearly a bad idea. RFC1035
+ * syntax does not make any distinction between a single RFC822
+ * quoted-string containing full stops, and a series of quoted-strings
+ * separated by full stops; adns will return anything that isn't all
+ * valid atoms as a single quoted-string. RFC822 does not allow
+ * high-bit-set characters at all, but adns does allow them in
+ * local-parts, treating them as needing quoting.
*
* If you ask for the domain with _raw then _no_ checking is done
* (even on the host part, regardless of adns_qf_quoteok_anshost), and
* you just get the domain name in master file format.
*
* If no mailbox is supplied the returned string will be `.' in either
- * caswe.
+ * case.
*/
typedef enum {
- adns_s_ok,
-
- /* locally induced errors */
- adns_s_nomemory,
- adns_s_unknownrrtype,
- adns_s_systemfail,
-
- adns_s_max_localfail= 29,
-
- /* remotely induced errors, detected locally */
- adns_s_timeout,
- adns_s_allservfail,
- adns_s_norecurse,
- adns_s_invalidresponse,
- adns_s_unknownformat,
-
- adns_s_max_remotefail= 59,
-
- /* remotely induced errors, reported by remote server to us */
- adns_s_rcodeservfail,
- adns_s_rcodeformaterror,
- adns_s_rcodenotimplemented,
- adns_s_rcoderefused,
- adns_s_rcodeunknown,
-
- adns_s_max_tempfail= 99,
-
- /* remote configuration errors */
- adns_s_inconsistent, /* PTR gives domain whose A does not exist and match */
- adns_s_prohibitedcname, /* CNAME found where eg A expected (not if _qf_loosecname) */
- adns_s_answerdomaininvalid,
- adns_s_answerdomaintoolong,
- adns_s_invaliddata,
-
- adns_s_max_misconfig= 199,
-
- /* permanent problems with the query */
- adns_s_querydomainwrong,
- adns_s_querydomaininvalid,
- adns_s_querydomaintoolong,
-
- adns_s_max_misquery= 299,
-
- /* permanent errors */
- adns_s_nxdomain,
- adns_s_nodata,
-
+ adns_s_ok,
+
+ /* locally induced errors */
+ adns_s_nomemory,
+ adns_s_unknownrrtype,
+ adns_s_systemfail,
+
+ adns_s_max_localfail= 29,
+
+ /* remotely induced errors, detected locally */
+ adns_s_timeout,
+ adns_s_allservfail,
+ adns_s_norecurse,
+ adns_s_invalidresponse,
+ adns_s_unknownformat,
+
+ adns_s_max_remotefail= 59,
+
+ /* remotely induced errors, reported by remote server to us */
+ adns_s_rcodeservfail,
+ adns_s_rcodeformaterror,
+ adns_s_rcodenotimplemented,
+ adns_s_rcoderefused,
+ adns_s_rcodeunknown,
+
+ adns_s_max_tempfail= 99,
+
+ /* remote configuration errors */
+ adns_s_inconsistent, /* PTR gives domain whose addr is missing or mismatch */
+ adns_s_prohibitedcname, /* CNAME, but eg A expected (not if _qf_cname_loose) */
+ adns_s_answerdomaininvalid,
+ adns_s_answerdomaintoolong,
+ adns_s_invaliddata,
+
+ adns_s_max_misconfig= 199,
+
+ /* permanent problems with the query */
+ adns_s_querydomainwrong,
+ adns_s_querydomaininvalid,
+ adns_s_querydomaintoolong,
+
+ adns_s_max_misquery= 299,
+
+ /* permanent errors */
+ adns_s_nxdomain,
+ adns_s_nodata,
+
+ adns_s_max_permfail= 499
+
} adns_status;
+typedef union {
+ struct sockaddr sa;
+ struct sockaddr_in inet;
+} adns_sockaddr_v4only;
+
+typedef union {
+ struct sockaddr sa;
+ struct sockaddr_in inet;
+ struct sockaddr_in6 inet6;
+} adns_sockaddr;
+
typedef struct {
int len;
- union {
- struct sockaddr sa;
- struct sockaddr_in inet;
- } addr;
+ adns_sockaddr addr;
} adns_rr_addr;
+typedef struct {
+ /* the old v4-only structure; handy if you have complicated binary
+ * compatibility problems. */
+ int len;
+ adns_sockaddr_v4only addr;
+} adns_rr_addr_v4only;
+
typedef struct {
char *host;
adns_status astatus;
} adns_rr_inthostaddr;
typedef struct {
- /* Used both for mx_raw, in which case i is the preference and str the domain,
- * and for txt, in which case each entry has i for the `text' length,
- * and str for the data (which will have had an extra nul appended
- * so that if it was plain text it is now a null-terminated string).
+ /* Used both for mx_raw, in which case i is the preference and str
+ * the domain, and for txt, in which case each entry has i for the
+ * `text' length, and str for the data (which will have had an extra
+ * nul appended so that if it was plain text it is now a
+ * null-terminated string).
*/
int i;
char *str;
unsigned long serial, refresh, retry, expire, minimum;
} adns_rr_soa;
+typedef struct {
+ int priority, weight, port;
+ char *host;
+} adns_rr_srvraw;
+
+typedef struct {
+ int priority, weight, port;
+ adns_rr_hostaddr ha;
+} adns_rr_srvha;
+
+typedef struct {
+ int len;
+ unsigned char *data;
+} adns_rr_byteblock;
+
typedef struct {
adns_status status;
char *cname; /* always NULL if query was for CNAME records */
- char *owner; /* only set if requested in query flags */
+ char *owner; /* only set if req'd in query flags; maybe 0 on error anyway */
adns_rrtype type; /* guaranteed to be same as in query */
- time_t expires; /* expiry time, defined only if _s_ok, nxdomain or nodata. NOT TTL! */
+ time_t expires;/*abs time. def only if _s_ok, nxdomain or nodata. NOT TTL!*/
int nrrs, rrsz; /* nrrs is 0 if an error occurs */
union {
void *untyped;
unsigned char *bytes;
- char *(*str); /* ns_raw, cname, ptr, ptr_raw */
- adns_rr_intstr *(*manyistr); /* txt (list of strings ends with i=-1, str=0) */
- adns_rr_addr *addr; /* addr */
- struct in_addr *inaddr; /* a */
- adns_rr_hostaddr *hostaddr; /* ns */
- adns_rr_intstrpair *intstrpair; /* hinfo */
- adns_rr_strpair *strpair; /* rp, rp_raw */
- adns_rr_inthostaddr *inthostaddr; /* mx */
- adns_rr_intstr *intstr; /* mx_raw */
- adns_rr_soa *soa; /* soa, soa_raw */
+ char *(*str); /* ns_raw, cname, ptr, ptr_raw */
+ adns_rr_intstr *(*manyistr); /* txt (list strs ends with i=-1, str=0)*/
+ adns_rr_addr *addr; /* addr */
+ struct in_addr *inaddr; /* a */
+ struct in6_addr *in6addr; /* aaaa */
+ adns_rr_hostaddr *hostaddr; /* ns */
+ adns_rr_intstrpair *intstrpair; /* hinfo */
+ adns_rr_strpair *strpair; /* rp, rp_raw */
+ adns_rr_inthostaddr *inthostaddr;/* mx */
+ adns_rr_intstr *intstr; /* mx_raw */
+ adns_rr_soa *soa; /* soa, soa_raw */
+ adns_rr_srvraw *srvraw; /* srv_raw */
+ adns_rr_srvha *srvha;/* srv */
+ adns_rr_byteblock *byteblock; /* ...|unknown */
} rrs;
} adns_answer;
*
* For _init, _init_strcfg, _submit and _synchronous, system errors
* (eg, failure to create sockets, malloc failure, etc.) return errno
- * values.
+ * values. EINVAL from _init et al means the configuration file
+ * is erroneous and cannot be parsed.
*
* For _wait and _check failures are reported in the answer
- * structure, and only 0, ESRCH or (for _check) EWOULDBLOCK is
+ * structure, and only 0, ESRCH or (for _check) EAGAIN is
* returned: if no (appropriate) requests are done adns_check returns
- * EWOULDBLOCK; if no (appropriate) requests are outstanding both
+ * EAGAIN; if no (appropriate) requests are outstanding both
* adns_query and adns_wait return ESRCH.
*
* Additionally, _wait can return EINTR if you set adns_if_eintr.
* requested.
*/
+/* Threads:
+ * adns does not use any static modifiable state, so it
+ * is safe to call adns_init several times and then use the
+ * resulting adns_states concurrently.
+ * However, it is NOT safe to make simultaneous calls into
+ * adns using the same adns_state; a single adns_state must be used
+ * only by one thread at a time. You can solve this problem by
+ * having one adns_state per thread, or if that isn't feasible, you
+ * could maintain a pool of adns_states. Unfortunately neither of
+ * these approaches has optimal performance.
+ */
+
int adns_init(adns_state *newstate_r, adns_initflags flags,
FILE *diagfile /*0=>stderr*/);
int adns_init_strcfg(adns_state *newstate_r, adns_initflags flags,
FILE *diagfile /*0=>discard*/, const char *configtext);
+typedef void adns_logcallbackfn(adns_state ads, void *logfndata,
+ const char *fmt, va_list al);
+ /* Will be called perhaps several times for each message; when the
+ * message is complete, the string implied by fmt and al will end in
+ * a newline. Log messages start with `adns debug:' or `adns
+ * warning:' or `adns:' (for errors), or `adns debug [PID]:'
+ * etc. if adns_if_logpid is set. */
+
+int adns_init_logfn(adns_state *newstate_r, adns_initflags flags,
+ const char *configtext /*0=>use default config files*/,
+ adns_logcallbackfn *logfn /*0=>logfndata is a FILE* */,
+ void *logfndata /*0 with logfn==0 => discard*/);
+
+/* Configuration:
+ * adns_init reads /etc/resolv.conf, which is expected to be (broadly
+ * speaking) in the format expected by libresolv, and then
+ * /etc/resolv-adns.conf if it exists. adns_init_strcfg is instead
+ * passed a string which is interpreted as if it were the contents of
+ * resolv.conf or resolv-adns.conf. In general, configuration which
+ * is set later overrides any that is set earlier.
+ *
+ * Standard directives understood in resolv[-adns].conf:
+ *
+ * nameserver <address>
+ * Must be followed by the IP address of a nameserver. Several
+ * nameservers may be specified, and they will be tried in the order
+ * found. There is a compiled in limit, currently 5, on the number
+ * of nameservers. (libresolv supports only 3 nameservers.)
+ *
+ * search <domain> ...
+ * Specifies the search list for queries which specify
+ * adns_qf_search. This is a list of domains to append to the query
+ * domain. The query domain will be tried as-is either before all
+ * of these or after them, depending on the ndots option setting
+ * (see below).
+ *
+ * domain <domain>
+ * This is present only for backward compatibility with obsolete
+ * versions of libresolv. It should not be used, and is interpreted
+ * by adns as if it were `search' - note that this is subtly
+ * different to libresolv's interpretation of this directive.
+ *
+ * sortlist <addr>/<mask> ...
+ * Should be followed by a sequence of IP-address and netmask pairs,
+ * separated by spaces. They may be specified as
+ * eg. 172.30.206.0/24 or 172.30.206.0/255.255.255.0. Currently up
+ * to 15 pairs may be specified (but note that libresolv only
+ * supports up to 10).
+ *
+ * options
+ * Should followed by one or more options, separated by spaces.
+ * Each option consists of an option name, followed by optionally
+ * a colon and a value. Options are listed below.
+ *
+ * Non-standard directives understood in resolv[-adns].conf:
+ *
+ * clearnameservers
+ * Clears the list of nameservers, so that further nameserver lines
+ * start again from the beginning.
+ *
+ * include <filename>
+ * The specified file will be read.
+ *
+ * Additionally, adns will ignore lines in resolv[-adns].conf which
+ * start with a #.
+ *
+ * Standard options understood:
+ *
+ * debug
+ * Enables debugging output from the resolver, which will be written
+ * to stderr.
+ *
+ * ndots:<count>
+ * Affects whether queries with adns_qf_search will be tried first
+ * without adding domains from the searchlist, or whether the bare
+ * query domain will be tried last. Queries which contain at least
+ * <count> dots will be tried bare first. The default is 1.
+ *
+ * Non-standard options understood:
+ *
+ * adns_checkc:none
+ * adns_checkc:entex
+ * adns_checkc:freq
+ * Changes the consistency checking frequency; this overrides the
+ * setting of adns_if_check_entex, adns_if_check_freq, or neither,
+ * in the flags passed to adns_init.
+ *
+ * adns_af:{ipv4,ipv6},... adns_af:any
+ * Determines which address families ADNS looks up (either as an
+ * adns_r_addr query, or when dereferencing an answer yielding hostnames
+ * (e.g., adns_r_mx). The argument is a comma-separated list: only the
+ * address families listed will be looked up. The default is `any'.
+ * Lookups occur (logically) concurrently; use the `sortlist' directive to
+ * control the relative order of addresses in answers. This option
+ * overrides the corresponding init flags (covered by adns_if_afmask).
+ *
+ * There are a number of environment variables which can modify the
+ * behaviour of adns. They take effect only if adns_init is used, and
+ * the caller of adns_init can disable them using adns_if_noenv. In
+ * each case there is both a FOO and an ADNS_FOO; the latter is
+ * interpreted later so that it can override the former. Unless
+ * otherwise stated, environment variables are interpreted after
+ * resolv[-adns].conf are read, in the order they are listed here.
+ *
+ * RES_CONF, ADNS_RES_CONF
+ * A filename, whose contets are in the format of resolv.conf.
+ *
+ * RES_CONF_TEXT, ADNS_RES_CONF_TEXT
+ * A string in the format of resolv.conf.
+ *
+ * RES_OPTIONS, ADNS_RES_OPTIONS
+ * These are parsed as if they appeared in the `options' line of a
+ * resolv.conf. In addition to being parsed at this point in the
+ * sequence, they are also parsed at the very beginning before
+ * resolv.conf or any other environment variables are read, so that
+ * any debug option can affect the processing of the configuration.
+ *
+ * LOCALDOMAIN, ADNS_LOCALDOMAIN
+ * These are interpreted as if their contents appeared in a `search'
+ * line in resolv.conf.
+ */
+
int adns_synchronous(adns_state ads,
const char *owner,
adns_rrtype type,
void *context,
adns_query *query_r);
+/* The owner should be quoted in master file format. */
+
int adns_check(adns_state ads,
adns_query *query_io,
adns_answer **answer_r,
adns_answer **answer_r,
void **context_r);
+/* same as adns_wait but uses poll(2) internally */
+int adns_wait_poll(adns_state ads,
+ adns_query *query_io,
+ adns_answer **answer_r,
+ void **context_r);
+
void adns_cancel(adns_query query);
/* The adns_query you get back from _submit is valid (ie, can be
adns_queryflags flags,
void *context,
adns_query *query_r);
-/* type must be _r_ptr or _r_ptr_raw. _qf_search is ignored. */
+/* type must be _r_ptr or _r_ptr_raw. _qf_search is ignored.
+ * addr->sa_family must be AF_INET or you get ENOSYS.
+ */
+
+int adns_submit_reverse_any(adns_state ads,
+ const struct sockaddr *addr,
+ const char *rzone,
+ adns_rrtype type,
+ adns_queryflags flags,
+ void *context,
+ adns_query *query_r);
+/* For RBL-style reverse `zone's; look up
+ * <reversed-address>.<zone>
+ * Any type is allowed. _qf_search is ignored.
+ * addr->sa_family must be AF_INET or you get ENOSYS.
+ */
void adns_finish(adns_state ads);
/* You may call this even if you have queries outstanding;
* they will be cancelled.
*/
+#define ADNS_ADDR2TEXT_BUFLEN \
+ (INET6_ADDRSTRLEN + 1/*%*/ \
+ + ((IF_NAMESIZE-1) > 9 ? (IF_NAMESIZE-1) : 9/*uint32*/) \
+ + 1/* nul; included in IF_NAMESIZE */)
+
+int adns_text2addr(const char *text, uint16_t port, adns_queryflags flags,
+ struct sockaddr *sa_r,
+ socklen_t *salen_io /* updated iff OK or ENOSPC */);
+int adns_addr2text(const struct sockaddr *sa, adns_queryflags flags,
+ char *buffer, int *buflen_io /* updated ONLY on ENOSPC */,
+ int *port_r /* may be 0 */);
+ /*
+ * port is always in host byte order and is simply copied to and
+ * from the appropriate sockaddr field (byteswapped as necessary).
+ *
+ * The only flags supported are adns_qf_addrlit_...
+ *
+ * Error return values are:
+ *
+ * ENOSPC Output buffer is too small. Can only happen if
+ * *buflen_io < ADNS_ADDR2TEXT_BUFLEN or
+ * *salen_io < sizeof(adns_sockaddr). On return,
+ * *buflen_io or *salen_io has been updated by adns.
+ *
+ * EINVAL text has invalid syntax.
+ *
+ * text represents an address family not supported by
+ * this version of adns.
+ *
+ * Scoped address supplied (text contained "%" or
+ * sin6_scope_id nonzero) but caller specified
+ * adns_qf_addrlit_scope_forbid.
+ *
+ * Scope name (rather than number) supplied in text but
+ * caller specified adns_qf_addrlit_scope_numeric.
+ *
+ * EAFNOSUPPORT sa->sa_family is not supported (addr2text only).
+ *
+ * ENOSYS Unsupported flags set.
+ *
+ * Only if neither adns_qf_addrlit_scope_forbid nor
+ * adns_qf_addrlit_scope_numeric are set:
+ *
+ * ENOSYS Scope name supplied in text but IPv6 address part of
+ * sockaddr is not a link local address.
+ *
+ * ENXIO Scope name supplied in text but if_nametoindex
+ * said it wasn't a valid local interface name.
+ *
+ * EIO Scoped address supplied but if_nametoindex failed
+ * in an unexpected way; adns has printed a message to
+ * stderr.
+ *
+ * any other if_nametoindex failed in a more-or-less expected way.
+ */
void adns_forallqueries_begin(adns_state ads);
adns_query adns_forallqueries_next(adns_state ads, void **context_r);
* context_r may be 0. *context_r may not be set when _next returns 0.
*/
-void adns_checkconsistency(adns_state ads);
+void adns_checkconsistency(adns_state ads, adns_query qu);
/* Checks the consistency of adns's internal data structures.
* If any error is found, the program will abort().
+ * You may pass 0 for qu; if you pass non-null then additional checks
+ * are done to make sure that qu is a valid query.
*/
/*
* adns_submit 2
* adns_submit 3
* adns_wait 1
- * adns_check 3 -> EWOULDBLOCK
+ * adns_check 3 -> EAGAIN
* adns_wait 2
* adns_wait 3
* ....
* from, or send outgoing data via, fd. Very like _processany. If it
* returns zero then fd will no longer be readable or writeable
* (unless of course more data has arrived since). adns will _only_
- * that fd and only in the manner specified, regardless of whether
+ * use that fd and only in the manner specified, regardless of whether
* adns_if_noautosys was specified.
*
* adns_processexceptional should be called when select(2) reports an
* for adns_firsttimeout. readfds, writefds, exceptfds and maxfd_io may
* not be 0.
*
- * If *now is not 0 then this will never actually do any I/O, or
- * change the fds that adns is using or the timeouts it wants. In any
- * case it won't block.
+ * If tv_mod is 0 on entry then this will never actually do any I/O,
+ * or change the fds that adns is using or the timeouts it wants. In
+ * any case it won't block, and it will set the timeout to zero if a
+ * query finishes in _beforeselect.
*/
void adns_afterselect(adns_state ads, int maxfd, const fd_set *readfds,
* entrypoints will not be defined in libadns. Sorry !
*/
-int adns_beforepoll(adns_state ads, struct pollfd *fds, int *nfds_io, int *timeout_io,
+int adns_beforepoll(adns_state ads, struct pollfd *fds,
+ int *nfds_io, int *timeout_io,
const struct timeval *now);
/* Finds out which fd's adns is interested in, and when it would like
* to be able to time things out. This is in a form suitable for use
* in *nfds_io, and always return either 0 (if it is not interested in
* any fds) or ERANGE (if it is).
*
- * NOTE that (unless timeout_io is 0) adns may acquire additional fds
+ * NOTE that (unless now is 0) adns may acquire additional fds
* from one call to the next, so you must put adns_beforepoll in a
* loop, rather than assuming that the second call (with the buffer
* size requested by the first) will not return ERANGE.
* adns_beforepoll will return 0 on success, and will not fail for any
* reason other than the fds buffer being too small (ERANGE).
*
- * This call will never actually do any I/O, or change the fds that
- * adns is using or the timeouts it wants; and in any case it won't
- * block.
+ * This call will never actually do any I/O. If you supply the
+ * current time it will not change the fds that adns is using or the
+ * timeouts it wants.
+ *
+ * In any case this call won't block.
*/
-#define ADNS_POLLFDS_RECOMMENDED 2
+#define ADNS_POLLFDS_RECOMMENDED 3
/* If you allocate an fds buf with at least RECOMMENDED entries then
* you are unlikely to need to enlarge it. You are recommended to do
* so if it's convenient. However, you must be prepared for adns to
int *len_r,
const void *datap, char **data_r);
/*
-
* Get information about a query type, or convert reply data to a
* textual form. type must be specified, and the official name of the
* corresponding RR type will be returned in *rrtname_r, and
* hostname, as usual, followed by the adns_status value, as an
* abbreviation, and then a descriptive string (encoded as if it were
* a piece of text), for the address lookup, followed by zero or more
- * addresses enclosed in ( and ). If the result was a permanent
+ * addresses enclosed in ( and ). If the result was a temporary
* failure, then a single ? appears instead of the ( ). If the
- * result was a temporary failure then an empty pair of parentheses
+ * result was a permanent failure then an empty pair of parentheses
* appears (which a space in between). For example, one of the NS
* records for greenend.org.uk comes out like
* ns.chiark.greenend.org.uk ok "OK" ( INET 195.224.76.132 )
const char *adns_strerror(adns_status st);
const char *adns_errabbrev(adns_status st);
+const char *adns_errtypeabbrev(adns_status st);
/* Like strerror but for adns_status values. adns_errabbrev returns
* the abbreviation of the error - eg, for adns_s_timeout it returns
- * "timeout". You MUST NOT call these functions with status values
+ * "timeout". adns_errtypeabbrev returns the abbreviation of the
+ * error class: ie, for values up to adns_s_max_XXX it will return the
+ * string XXX. You MUST NOT call these functions with status values
* not returned by the same adns library.
*/