X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=adns.git;a=blobdiff_plain;f=src%2Fadns.h;h=c75dbb6014b168bf5fd842fbdbf6ca220356922f;hp=a9039346324cbe865f43473f6460ba0bb225c907;hb=2a9e6abd955dc1d32f298ff99376096c634f47ff;hpb=47a6797e30861e0b59f6badcfb5ef7a1a020befa diff --git a/src/adns.h b/src/adns.h index a903934..c75dbb6 100644 --- a/src/adns.h +++ b/src/adns.h @@ -66,11 +66,31 @@ #include #include #include +#include #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; @@ -87,7 +107,17 @@ typedef enum { /* In general, or together the desired flags: */ 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_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_initflags; typedef enum { /* In general, or together the desired flags: */ @@ -101,14 +131,39 @@ typedef enum { /* In general, or together the desired flags: */ 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_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 % in IPv6 literals */ + adns_qf_addrlit_scope_numeric=0x00004000,/* % may only be numeric */ + adns_qf_addrlit_ipv4_quadonly=0x00008000,/* reject non-dotted-quad ipv4 */ + adns__qf_internalmask= 0x0ff00000 } adns_queryflags; typedef enum { adns_rrt_typemask= 0x0ffff, - adns__qtf_deref= 0x10000,/* dereference domains; perhaps get extra data */ + 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 |adns_r_unknown. * adns will not process the RDATA - you'll get adns_rr_byteblocks, @@ -152,6 +207,8 @@ typedef enum { 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. */ @@ -282,14 +339,29 @@ typedef enum { } 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; @@ -355,6 +427,7 @@ typedef struct { 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 */ @@ -505,6 +578,15 @@ int adns_init_logfn(adns_state *newstate_r, adns_initflags flags, * 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 @@ -610,6 +692,60 @@ void adns_finish(adns_state ads); * 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_...; others are + * ignored. + * + * 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). + * + * 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); @@ -830,7 +966,7 @@ int adns_beforepoll(adns_state ads, struct pollfd *fds, * 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