Index: head/lib/libc/net/getaddrinfo.3 =================================================================== --- head/lib/libc/net/getaddrinfo.3 (revision 323596) +++ head/lib/libc/net/getaddrinfo.3 (revision 323597) @@ -1,509 +1,520 @@ .\" $KAME: getaddrinfo.3,v 1.36 2005/01/05 03:23:05 itojun Exp $ .\" $OpenBSD: getaddrinfo.3,v 1.35 2004/12/21 03:40:31 jaredy Exp $ .\" .\" Copyright (C) 2004 Internet Systems Consortium, Inc. ("ISC") .\" Copyright (C) 2000, 2001 Internet Software Consortium. .\" .\" Permission to use, copy, modify, and distribute this software for any .\" purpose with or without fee is hereby granted, provided that the above .\" copyright notice and this permission notice appear in all copies. .\" .\" THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH .\" REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY .\" AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, .\" INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM .\" LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE .\" OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR .\" PERFORMANCE OF THIS SOFTWARE. .\" .\" $FreeBSD$ .\" -.Dd December 21, 2015 +.Dd September 13, 2017 .Dt GETADDRINFO 3 .Os .Sh NAME .Nm getaddrinfo , .Nm freeaddrinfo .Nd socket address structure to host and service name .Sh SYNOPSIS .In sys/types.h .In sys/socket.h .In netdb.h .Ft int .Fo getaddrinfo .Fa "const char *hostname" "const char *servname" .Fa "const struct addrinfo *hints" "struct addrinfo **res" .Fc .Ft void .Fn freeaddrinfo "struct addrinfo *ai" .Sh DESCRIPTION The .Fn getaddrinfo function is used to get a list of addresses and port numbers for host .Fa hostname and service .Fa servname . It is a replacement for and provides more flexibility than the .Xr gethostbyname 3 and .Xr getservbyname 3 functions. .Pp The .Fa hostname and .Fa servname arguments are either pointers to NUL-terminated strings or the null pointer. An acceptable value for .Fa hostname is either a valid host name or a numeric host address string consisting of a dotted decimal IPv4 address, an IPv6 address, or a UNIX-domain address. The .Fa servname is either a decimal port number or a service name listed in .Xr services 5 . At least one of .Fa hostname and .Fa servname must be non-null. .Pp .Fa hints is an optional pointer to a .Li struct addrinfo , as defined by .Aq Pa netdb.h : .Bd -literal struct addrinfo { int ai_flags; /* input flags */ int ai_family; /* address family for socket */ int ai_socktype; /* socket type */ int ai_protocol; /* protocol for socket */ socklen_t ai_addrlen; /* length of socket-address */ struct sockaddr *ai_addr; /* socket-address for socket */ char *ai_canonname; /* canonical name for service location */ struct addrinfo *ai_next; /* pointer to next in list */ }; .Ed .Pp This structure can be used to provide hints concerning the type of socket that the caller supports or wishes to use. The caller can supply the following structure elements in .Fa hints : .Bl -tag -width "ai_socktypeXX" .It Fa ai_family The address family that should be used. When .Fa ai_family is set to .Dv AF_UNSPEC , it means the caller will accept any address family supported by the operating system. .It Fa ai_socktype Denotes the type of socket that is wanted: .Dv SOCK_STREAM , .Dv SOCK_DGRAM , .Dv SOCK_SEQPACKET , or .Dv SOCK_RAW . When .Fa ai_socktype is zero the caller will accept any socket type. .It Fa ai_protocol Indicates which transport protocol is desired, .Dv IPPROTO_UDP , .Dv IPPROTO_TCP , .Dv IPPROTO_SCTP , or .Dv IPPROTO_UDPLITE . If .Fa ai_protocol is zero the caller will accept any protocol. .It Fa ai_flags The .Fa ai_flags field to which the .Fa hints parameter points shall be set to zero or be the bitwise-inclusive OR of one or more of the values .Dv AI_ADDRCONFIG , .Dv AI_ALL , .Dv AI_CANONNAME , .Dv AI_NUMERICHOST , .Dv AI_NUMERICSERV , .Dv AI_PASSIVE and .Dv AI_V4MAPPED . For a UNIX-domain address, .Fa ai_flags is ignored. .Bl -tag -width "AI_CANONNAMEXX" .It Dv AI_ADDRCONFIG If the .Dv AI_ADDRCONFIG bit is set, IPv4 addresses shall be returned only if an IPv4 address is configured on the local system, and IPv6 addresses shall be returned only if an IPv6 address is configured on the local system. .It Dv AI_ALL If the .Dv AI_ALL flag is used with the .Dv AI_V4MAPPED flag, then .Fn getaddrinfo shall return all matching IPv6 and IPv4 addresses. .Pp For example, when using the DNS, queries are made for both AAAA records and A records, and .Fn getaddrinfo returns the combined results of both queries. Any IPv4 addresses found are returned as IPv4-mapped IPv6 addresses. .Pp The .Dv AI_ALL flag without the .Dv AI_V4MAPPED flag is ignored. .It Dv AI_CANONNAME If the .Dv AI_CANONNAME bit is set, a successful call to .Fn getaddrinfo will return a NUL-terminated string containing the canonical name of the specified hostname in the .Fa ai_canonname element of the first .Li addrinfo structure returned. .It Dv AI_NUMERICHOST If the .Dv AI_NUMERICHOST bit is set, it indicates that .Fa hostname should be treated as a numeric string defining an IPv4 or IPv6 address and no name resolution should be attempted. .It Dv AI_NUMERICSERV If the .Dv AI_NUMERICSERV bit is set, then a non-null .Fa servname string supplied shall be a numeric port string. Otherwise, an .Dv EAI_NONAME error shall be returned. This bit shall prevent any type of name resolution service (for example, NIS+) from being invoked. .It Dv AI_PASSIVE If the .Dv AI_PASSIVE bit is set it indicates that the returned socket address structure is intended for use in a call to .Xr bind 2 . In this case, if the .Fa hostname argument is the null pointer, then the IP address portion of the socket address structure will be set to .Dv INADDR_ANY for an IPv4 address or .Dv IN6ADDR_ANY_INIT for an IPv6 address. .Pp If the .Dv AI_PASSIVE bit is not set, the returned socket address structure will be ready for use in a call to .Xr connect 2 for a connection-oriented protocol or .Xr connect 2 , .Xr sendto 2 , or .Xr sendmsg 2 if a connectionless protocol was chosen. The .Tn IP address portion of the socket address structure will be set to the loopback address if .Fa hostname is the null pointer and .Dv AI_PASSIVE is not set. .It Dv AI_V4MAPPED If the .Dv AI_V4MAPPED flag is specified along with an ai_family of .Dv AF_INET6 , then .Fn getaddrinfo shall return IPv4-mapped IPv6 addresses on finding no matching IPv6 addresses ( .Fa ai_addrlen shall be 16). .Pp For example, when using the DNS, if no AAAA records are found then a query is made for A records and any found are returned as IPv4-mapped IPv6 addresses. .Pp The .Dv AI_V4MAPPED flag shall be ignored unless .Fa ai_family equals .Dv AF_INET6 . .El .El .Pp All other elements of the .Li addrinfo structure passed via .Fa hints must be zero or the null pointer. .Pp If .Fa hints is the null pointer, .Fn getaddrinfo behaves as if the caller provided a .Li struct addrinfo with .Fa ai_family set to .Dv AF_UNSPEC and all other elements set to zero or .Dv NULL . .Pp After a successful call to .Fn getaddrinfo , .Fa *res is a pointer to a linked list of one or more .Li addrinfo structures. The list can be traversed by following the .Fa ai_next pointer in each .Li addrinfo structure until a null pointer is encountered. Each returned .Li addrinfo structure contains three members that are suitable for a call to .Xr socket 2 : .Fa ai_family , .Fa ai_socktype , and .Fa ai_protocol . For each .Li addrinfo structure in the list, the .Fa ai_addr member points to a filled-in socket address structure of length .Fa ai_addrlen . .Pp This implementation of .Fn getaddrinfo allows numeric IPv6 address notation with scope identifier, as documented in chapter 11 of RFC 4007. By appending the percent character and scope identifier to addresses, one can fill the .Li sin6_scope_id field for addresses. This would make management of scoped addresses easier and allows cut-and-paste input of scoped addresses. .Pp At this moment the code supports only link-local addresses with the format. The scope identifier is hardcoded to the name of the hardware interface associated with the link .Po such as .Li ne0 .Pc . An example is .Dq Li fe80::1%ne0 , which means .Do .Li fe80::1 on the link associated with the .Li ne0 interface .Dc . .Pp The current implementation assumes a one-to-one relationship between the interface and link, which is not necessarily true from the specification. .Pp All of the information returned by .Fn getaddrinfo is dynamically allocated: the .Li addrinfo structures themselves as well as the socket address structures and the canonical host name strings included in the .Li addrinfo structures. .Pp Memory allocated for the dynamically allocated structures created by a successful call to .Fn getaddrinfo is released by the .Fn freeaddrinfo function. The .Fa ai pointer should be a .Li addrinfo structure created by a call to .Fn getaddrinfo . +.Sh IMPLEMENTATION NOTES +The behavior of +.Li freeadrinfo(NULL) +is left unspecified by both +.St -susv4 +and +.Dv "RFC 3493" . +The current implementation ignores a +.Dv NULL +argument for compatibility with programs that rely on the implementation +details of other operating systems. .Sh RETURN VALUES .Fn getaddrinfo returns zero on success or one of the error codes listed in .Xr gai_strerror 3 if an error occurs. .Sh EXAMPLES The following code tries to connect to .Dq Li www.kame.net service .Dq Li http via a stream socket. It loops through all the addresses available, regardless of address family. If the destination resolves to an IPv4 address, it will use an .Dv AF_INET socket. Similarly, if it resolves to IPv6, an .Dv AF_INET6 socket is used. Observe that there is no hardcoded reference to a particular address family. The code works even if .Fn getaddrinfo returns addresses that are not IPv4/v6. .Bd -literal -offset indent struct addrinfo hints, *res, *res0; int error; int s; const char *cause = NULL; memset(&hints, 0, sizeof(hints)); hints.ai_family = AF_UNSPEC; hints.ai_socktype = SOCK_STREAM; error = getaddrinfo("www.kame.net", "http", &hints, &res0); if (error) { errx(1, "%s", gai_strerror(error)); /* NOTREACHED */ } s = -1; for (res = res0; res; res = res->ai_next) { s = socket(res->ai_family, res->ai_socktype, res->ai_protocol); if (s < 0) { cause = "socket"; continue; } if (connect(s, res->ai_addr, res->ai_addrlen) < 0) { cause = "connect"; close(s); s = -1; continue; } break; /* okay we got one */ } if (s < 0) { err(1, "%s", cause); /* NOTREACHED */ } freeaddrinfo(res0); .Ed .Pp The following example tries to open a wildcard listening socket onto service .Dq Li http , for all the address families available. .Bd -literal -offset indent struct addrinfo hints, *res, *res0; int error; int s[MAXSOCK]; int nsock; const char *cause = NULL; memset(&hints, 0, sizeof(hints)); hints.ai_family = AF_UNSPEC; hints.ai_socktype = SOCK_STREAM; hints.ai_flags = AI_PASSIVE; error = getaddrinfo(NULL, "http", &hints, &res0); if (error) { errx(1, "%s", gai_strerror(error)); /* NOTREACHED */ } nsock = 0; for (res = res0; res && nsock < MAXSOCK; res = res->ai_next) { s[nsock] = socket(res->ai_family, res->ai_socktype, res->ai_protocol); if (s[nsock] < 0) { cause = "socket"; continue; } if (bind(s[nsock], res->ai_addr, res->ai_addrlen) < 0) { cause = "bind"; close(s[nsock]); continue; } (void) listen(s[nsock], 5); nsock++; } if (nsock == 0) { err(1, "%s", cause); /* NOTREACHED */ } freeaddrinfo(res0); .Ed .Sh SEE ALSO .Xr bind 2 , .Xr connect 2 , .Xr send 2 , .Xr socket 2 , .Xr gai_strerror 3 , .Xr gethostbyname 3 , .Xr getnameinfo 3 , .Xr getservbyname 3 , .Xr resolver 3 , .Xr inet 4 , .Xr inet6 4 , .Xr unix 4 , .Xr hosts 5 , .Xr resolv.conf 5 , .Xr services 5 , .Xr hostname 7 , .Xr named 8 .Rs .%A R. Gilligan .%A S. Thomson .%A J. Bound .%A J. McCann .%A W. Stevens .%T Basic Socket Interface Extensions for IPv6 .%R RFC 3493 .%D February 2003 .Re .Rs .%A S. Deering .%A B. Haberman .%A T. Jinmei .%A E. Nordmark .%A B. Zill .%T "IPv6 Scoped Address Architecture" .%R RFC 4007 .%D March 2005 .Re .Rs .%A Craig Metz .%T Protocol Independence Using the Sockets API .%B "Proceedings of the freenix track: 2000 USENIX annual technical conference" .%D June 2000 .Re .Sh STANDARDS The .Fn getaddrinfo function is defined by the .St -p1003.1-2004 specification and documented in .Dv "RFC 3493" , .Dq Basic Socket Interface Extensions for IPv6 . Index: head/lib/libc/net/getaddrinfo.c =================================================================== --- head/lib/libc/net/getaddrinfo.c (revision 323596) +++ head/lib/libc/net/getaddrinfo.c (revision 323597) @@ -1,3033 +1,3032 @@ /* $KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 itojun Exp $ */ /* * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * Issues to be discussed: * - Return values. There are nonstandard return values defined and used * in the source code. This is because RFC2553 is silent about which error * code must be returned for which situation. * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is - * invalid. current code - SEGV on freeaddrinfo(NULL) + * invalid. Current code accepts NULL to be compatible with other OSes. * * Note: * - The code filters out AFs that are not supported by the kernel, * when globbing NULL hostname (to loopback, or wildcard). Is it the right * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG * in ai_flags? * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. * (1) what should we do against numeric hostname (2) what should we do * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? * non-loopback address configured? global address configured? * * OS specific notes for freebsd4: * - FreeBSD supported $GAI. The code does not. */ #include __FBSDID("$FreeBSD$"); #include "namespace.h" #include #include #include #include #include #include #include #ifdef INET6 #include #include #include #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "res_config.h" #ifdef DEBUG #include #endif #include #include #include "un-namespace.h" #include "netdb_private.h" #include "libc_private.h" #ifdef NS_CACHING #include "nscache.h" #endif #define ANY 0 #define YES 1 #define NO 0 static const char in_addrany[] = { 0, 0, 0, 0 }; static const char in_loopback[] = { 127, 0, 0, 1 }; #ifdef INET6 static const char in6_addrany[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; static const char in6_loopback[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 }; #endif struct policyqueue { TAILQ_ENTRY(policyqueue) pc_entry; #ifdef INET6 struct in6_addrpolicy pc_policy; #endif }; TAILQ_HEAD(policyhead, policyqueue); static const struct afd { int a_af; int a_addrlen; socklen_t a_socklen; int a_off; const char *a_addrany; const char *a_loopback; int a_scoped; } afdl [] = { #ifdef INET6 #define N_INET6 0 {PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6), offsetof(struct sockaddr_in6, sin6_addr), in6_addrany, in6_loopback, 1}, #define N_INET 1 #define N_LOCAL 2 #else #define N_INET 0 #define N_LOCAL 1 #endif {PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in), offsetof(struct sockaddr_in, sin_addr), in_addrany, in_loopback, 0}, #define sizeofmember(type, member) (sizeof(((type *)0)->member)) {PF_LOCAL, sizeofmember(struct sockaddr_un, sun_path), sizeof(struct sockaddr_un), offsetof(struct sockaddr_un, sun_path), NULL, NULL, 0}, {0, 0, 0, 0, NULL, NULL, 0}, }; struct explore { int e_af; int e_socktype; int e_protocol; int e_wild; #define AF_ANY 0x01 #define SOCKTYPE_ANY 0x02 #define PROTOCOL_ANY 0x04 #define WILD_AF(ex) ((ex)->e_wild & AF_ANY) #define WILD_SOCKTYPE(ex) ((ex)->e_wild & SOCKTYPE_ANY) #define WILD_PROTOCOL(ex) ((ex)->e_wild & PROTOCOL_ANY) }; static const struct explore explore[] = { #ifdef INET6 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, AF_ANY | SOCKTYPE_ANY | PROTOCOL_ANY }, { PF_INET6, SOCK_STREAM, IPPROTO_TCP, AF_ANY | SOCKTYPE_ANY | PROTOCOL_ANY }, { PF_INET6, SOCK_STREAM, IPPROTO_SCTP, AF_ANY | SOCKTYPE_ANY }, { PF_INET6, SOCK_SEQPACKET, IPPROTO_SCTP, AF_ANY | SOCKTYPE_ANY | PROTOCOL_ANY }, { PF_INET6, SOCK_DGRAM, IPPROTO_UDPLITE, AF_ANY | SOCKTYPE_ANY }, { PF_INET6, SOCK_RAW, ANY, AF_ANY | PROTOCOL_ANY }, #endif { PF_INET, SOCK_DGRAM, IPPROTO_UDP, AF_ANY | SOCKTYPE_ANY | PROTOCOL_ANY }, { PF_INET, SOCK_STREAM, IPPROTO_TCP, AF_ANY | SOCKTYPE_ANY | PROTOCOL_ANY }, { PF_INET, SOCK_STREAM, IPPROTO_SCTP, AF_ANY | SOCKTYPE_ANY }, { PF_INET, SOCK_SEQPACKET, IPPROTO_SCTP, AF_ANY | SOCKTYPE_ANY | PROTOCOL_ANY }, { PF_INET, SOCK_DGRAM, IPPROTO_UDPLITE, AF_ANY | SOCKTYPE_ANY }, { PF_INET, SOCK_RAW, ANY, AF_ANY | PROTOCOL_ANY }, { PF_LOCAL, SOCK_DGRAM, ANY, AF_ANY | SOCKTYPE_ANY | PROTOCOL_ANY }, { PF_LOCAL, SOCK_STREAM, ANY, AF_ANY | SOCKTYPE_ANY | PROTOCOL_ANY }, { PF_LOCAL, SOCK_SEQPACKET, ANY, AF_ANY | SOCKTYPE_ANY | PROTOCOL_ANY }, { -1, 0, 0, 0 }, }; #ifdef INET6 #define PTON_MAX 16 #else #define PTON_MAX 4 #endif #define AIO_SRCFLAG_DEPRECATED 0x1 struct ai_order { union { struct sockaddr_storage aiou_ss; struct sockaddr aiou_sa; } aio_src_un; #define aio_srcsa aio_src_un.aiou_sa u_int32_t aio_srcflag; int aio_srcscope; int aio_dstscope; struct policyqueue *aio_srcpolicy; struct policyqueue *aio_dstpolicy; struct addrinfo *aio_ai; int aio_matchlen; int aio_initial_sequence; }; static const ns_src default_dns_files[] = { { NSSRC_FILES, NS_SUCCESS }, { NSSRC_DNS, NS_SUCCESS }, { 0 } }; struct res_target { struct res_target *next; const char *name; /* domain name */ int qclass, qtype; /* class and type of query */ u_char *answer; /* buffer to put answer */ int anslen; /* size of answer buffer */ int n; /* result length */ }; #define MAXPACKET (64*1024) typedef union { HEADER hdr; u_char buf[MAXPACKET]; } querybuf; static int str2number(const char *, int *); static int explore_copy(const struct addrinfo *, const struct addrinfo *, struct addrinfo **); static int explore_null(const struct addrinfo *, const char *, struct addrinfo **); static int explore_numeric(const struct addrinfo *, const char *, const char *, struct addrinfo **, const char *); static int explore_numeric_scope(const struct addrinfo *, const char *, const char *, struct addrinfo **); static int get_canonname(const struct addrinfo *, struct addrinfo *, const char *); static struct addrinfo *get_ai(const struct addrinfo *, const struct afd *, const char *); static struct addrinfo *copy_ai(const struct addrinfo *); static int get_portmatch(const struct addrinfo *, const char *); static int get_port(struct addrinfo *, const char *, int); static const struct afd *find_afd(int); static int addrconfig(struct addrinfo *); #ifdef INET6 static int is_ifdisabled(char *); #endif static void set_source(struct ai_order *, struct policyhead *); static int comp_dst(const void *, const void *); #ifdef INET6 static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); #endif static int gai_addr2scopetype(struct sockaddr *); static int explore_fqdn(const struct addrinfo *, const char *, const char *, struct addrinfo **); static int reorder(struct addrinfo *); static int get_addrselectpolicy(struct policyhead *); static void free_addrselectpolicy(struct policyhead *); static struct policyqueue *match_addrselectpolicy(struct sockaddr *, struct policyhead *); static int matchlen(struct sockaddr *, struct sockaddr *); static struct addrinfo *getanswer(const querybuf *, int, const char *, int, const struct addrinfo *, res_state); #if defined(RESOLVSORT) static int addr4sort(struct addrinfo *, res_state); #endif static int _dns_getaddrinfo(void *, void *, va_list); static void _sethtent(FILE **); static void _endhtent(FILE **); static struct addrinfo *_gethtent(FILE **, const char *, const struct addrinfo *); static int _files_getaddrinfo(void *, void *, va_list); #ifdef YP static struct addrinfo *_yphostent(char *, const struct addrinfo *); static int _yp_getaddrinfo(void *, void *, va_list); #endif #ifdef NS_CACHING static int addrinfo_id_func(char *, size_t *, va_list, void *); static int addrinfo_marshal_func(char *, size_t *, void *, va_list, void *); static int addrinfo_unmarshal_func(char *, size_t, void *, va_list, void *); #endif static int res_queryN(const char *, struct res_target *, res_state); static int res_searchN(const char *, struct res_target *, res_state); static int res_querydomainN(const char *, const char *, struct res_target *, res_state); /* XXX macros that make external reference is BAD. */ #define GET_AI(ai, afd, addr) \ do { \ /* external reference: pai, error, and label free */ \ (ai) = get_ai(pai, (afd), (addr)); \ if ((ai) == NULL) { \ error = EAI_MEMORY; \ goto free; \ } \ } while (/*CONSTCOND*/0) #define GET_PORT(ai, serv) \ do { \ /* external reference: error and label free */ \ error = get_port((ai), (serv), 0); \ if (error != 0) \ goto free; \ } while (/*CONSTCOND*/0) #define GET_CANONNAME(ai, str) \ do { \ /* external reference: pai, error and label free */ \ error = get_canonname(pai, (ai), (str)); \ if (error != 0) \ goto free; \ } while (/*CONSTCOND*/0) #define ERR(err) \ do { \ /* external reference: error, and label bad */ \ error = (err); \ goto bad; \ /*NOTREACHED*/ \ } while (/*CONSTCOND*/0) #define MATCH_FAMILY(x, y, w) \ ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) #define MATCH(x, y, w) \ ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) void freeaddrinfo(struct addrinfo *ai) { struct addrinfo *next; - do { + while (ai != NULL) { next = ai->ai_next; - if (ai->ai_canonname) - free(ai->ai_canonname); + free(ai->ai_canonname); /* no need to free(ai->ai_addr) */ free(ai); ai = next; - } while (ai); + } } static int str2number(const char *p, int *portp) { char *ep; unsigned long v; if (*p == '\0') return -1; ep = NULL; errno = 0; v = strtoul(p, &ep, 10); if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) { *portp = v; return 0; } else return -1; } int getaddrinfo(const char *hostname, const char *servname, const struct addrinfo *hints, struct addrinfo **res) { struct addrinfo sentinel; struct addrinfo *cur; int error = 0; struct addrinfo ai, ai0, *afai; struct addrinfo *pai; const struct afd *afd; const struct explore *ex; struct addrinfo *afailist[nitems(afdl)]; struct addrinfo *afai_unspec; int found; int numeric = 0; /* ensure we return NULL on errors */ *res = NULL; memset(&ai, 0, sizeof(ai)); memset(afailist, 0, sizeof(afailist)); afai_unspec = NULL; memset(&sentinel, 0, sizeof(sentinel)); cur = &sentinel; pai = &ai; pai->ai_flags = 0; pai->ai_family = PF_UNSPEC; pai->ai_socktype = ANY; pai->ai_protocol = ANY; pai->ai_addrlen = 0; pai->ai_canonname = NULL; pai->ai_addr = NULL; pai->ai_next = NULL; if (hostname == NULL && servname == NULL) return EAI_NONAME; if (hints) { /* error check for hints */ if (hints->ai_addrlen || hints->ai_canonname || hints->ai_addr || hints->ai_next) ERR(EAI_BADHINTS); /* xxx */ if (hints->ai_flags & ~AI_MASK) ERR(EAI_BADFLAGS); switch (hints->ai_family) { case PF_UNSPEC: case PF_LOCAL: case PF_INET: #ifdef INET6 case PF_INET6: #endif break; default: ERR(EAI_FAMILY); } memcpy(pai, hints, sizeof(*pai)); /* * if both socktype/protocol are specified, check if they * are meaningful combination. */ if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { for (ex = explore; ex->e_af >= 0; ex++) { if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) continue; if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) continue; if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) continue; /* matched */ break; } if (ex->e_af < 0) ERR(EAI_BADHINTS); } } /* * RFC 3493: AI_ALL and AI_V4MAPPED are effective only against * AF_INET6 query. They need to be ignored if specified in other * occasions. */ switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { case AI_V4MAPPED: case AI_ALL | AI_V4MAPPED: #ifdef INET6 if (pai->ai_family != AF_INET6) pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); break; #endif case AI_ALL: pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); break; } /* * check for special cases. (1) numeric servname is disallowed if * socktype/protocol are left unspecified. (2) servname is disallowed * for raw and other inet{,6} sockets. */ if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) #ifdef PF_INET6 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) #endif ) { ai0 = *pai; /* backup *pai */ if (pai->ai_family == PF_UNSPEC) { #ifdef PF_INET6 pai->ai_family = PF_INET6; #else pai->ai_family = PF_INET; #endif } error = get_portmatch(pai, servname); if (error) goto bad; *pai = ai0; } ai0 = *pai; /* * NULL hostname, or numeric hostname. * If numeric representation of AF1 can be interpreted as FQDN * representation of AF2, we need to think again about the code below. */ found = 0; for (afd = afdl; afd->a_af; afd++) { *pai = ai0; if (!MATCH_FAMILY(pai->ai_family, afd->a_af, 1)) continue; if (pai->ai_family == PF_UNSPEC) pai->ai_family = afd->a_af; if (hostname == NULL) { error = explore_null(pai, servname, &afailist[afd - afdl]); /* * Errors from explore_null should be unexpected and * be caught to avoid returning an incomplete result. */ if (error != 0) goto bad; } else { error = explore_numeric_scope(pai, hostname, servname, &afailist[afd - afdl]); /* * explore_numeric_scope returns an error for address * families that do not match that of hostname. * Thus we should not catch the error at this moment. */ } if (!error && afailist[afd - afdl]) found++; } if (found) { numeric = 1; goto globcopy; } if (hostname == NULL) ERR(EAI_NONAME); /* used to be EAI_NODATA */ if (pai->ai_flags & AI_NUMERICHOST) ERR(EAI_NONAME); if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) ERR(EAI_FAIL); /* * hostname as alphabetical name. */ *pai = ai0; error = explore_fqdn(pai, hostname, servname, &afai_unspec); globcopy: for (ex = explore; ex->e_af >= 0; ex++) { *pai = ai0; if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) continue; if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) continue; if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) continue; if (pai->ai_family == PF_UNSPEC) pai->ai_family = ex->e_af; if (pai->ai_socktype == ANY && ex->e_socktype != ANY) pai->ai_socktype = ex->e_socktype; if (pai->ai_protocol == ANY && ex->e_protocol != ANY) pai->ai_protocol = ex->e_protocol; /* * if the servname does not match socktype/protocol, ignore it. */ if (get_portmatch(pai, servname) != 0) continue; if (afai_unspec) afai = afai_unspec; else { if ((afd = find_afd(pai->ai_family)) == NULL) continue; /* XXX assumes that afd points inside afdl[] */ afai = afailist[afd - afdl]; } if (!afai) continue; error = explore_copy(pai, afai, &cur->ai_next); if (error != 0) goto bad; while (cur && cur->ai_next) cur = cur->ai_next; } /* * ensure we return either: * - error == 0, non-NULL *res * - error != 0, NULL *res */ if (error == 0) { if (sentinel.ai_next) { /* * If the returned entry is for an active connection, * and the given name is not numeric, reorder the * list, so that the application would try the list * in the most efficient order. Since the head entry * of the original list may contain ai_canonname and * that entry may be moved elsewhere in the new list, * we keep the pointer and will restore it in the new * head entry. (Note that RFC3493 requires the head * entry store it when requested by the caller). */ if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { if (!numeric) { char *canonname; canonname = sentinel.ai_next->ai_canonname; sentinel.ai_next->ai_canonname = NULL; (void)reorder(&sentinel); if (sentinel.ai_next->ai_canonname == NULL) { sentinel.ai_next->ai_canonname = canonname; } else if (canonname != NULL) free(canonname); } } *res = sentinel.ai_next; } else error = EAI_FAIL; } bad: if (afai_unspec) freeaddrinfo(afai_unspec); for (afd = afdl; afd->a_af; afd++) { if (afailist[afd - afdl]) freeaddrinfo(afailist[afd - afdl]); } if (!*res) if (sentinel.ai_next) freeaddrinfo(sentinel.ai_next); return (error); } static int reorder(struct addrinfo *sentinel) { struct addrinfo *ai, **aip; struct ai_order *aio; int i, n; struct policyhead policyhead; /* count the number of addrinfo elements for sorting. */ for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) ; /* * If the number is small enough, we can skip the reordering process. */ if (n <= 1) return(n); /* allocate a temporary array for sort and initialization of it. */ if ((aio = calloc(n, sizeof(*aio))) == NULL) return(n); /* give up reordering */ /* retrieve address selection policy from the kernel */ TAILQ_INIT(&policyhead); if (!get_addrselectpolicy(&policyhead)) { /* no policy is installed into kernel, we don't sort. */ free(aio); return (n); } for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { aio[i].aio_ai = ai; aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, &policyhead); set_source(&aio[i], &policyhead); aio[i].aio_initial_sequence = i; } /* perform sorting. */ qsort(aio, n, sizeof(*aio), comp_dst); /* reorder the addrinfo chain. */ for (i = 0, aip = &sentinel->ai_next; i < n; i++) { *aip = aio[i].aio_ai; aip = &aio[i].aio_ai->ai_next; } *aip = NULL; /* cleanup and return */ free(aio); free_addrselectpolicy(&policyhead); return(n); } static int get_addrselectpolicy(struct policyhead *head) { #ifdef INET6 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; size_t l; char *buf; struct in6_addrpolicy *pol, *ep; if (sysctl(mib, nitems(mib), NULL, &l, NULL, 0) < 0) return (0); if (l == 0) return (0); if ((buf = malloc(l)) == NULL) return (0); if (sysctl(mib, nitems(mib), buf, &l, NULL, 0) < 0) { free(buf); return (0); } ep = (struct in6_addrpolicy *)(buf + l); for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { struct policyqueue *new; if ((new = malloc(sizeof(*new))) == NULL) { free_addrselectpolicy(head); /* make the list empty */ break; } new->pc_policy = *pol; TAILQ_INSERT_TAIL(head, new, pc_entry); } free(buf); return (1); #else return (0); #endif } static void free_addrselectpolicy(struct policyhead *head) { struct policyqueue *ent, *nent; for (ent = TAILQ_FIRST(head); ent; ent = nent) { nent = TAILQ_NEXT(ent, pc_entry); TAILQ_REMOVE(head, ent, pc_entry); free(ent); } } static struct policyqueue * match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) { #ifdef INET6 struct policyqueue *ent, *bestent = NULL; struct in6_addrpolicy *pol; int matchlen, bestmatchlen = -1; u_char *mp, *ep, *k, *p, m; struct sockaddr_in6 key; switch(addr->sa_family) { case AF_INET6: key = *(struct sockaddr_in6 *)addr; break; case AF_INET: /* convert the address into IPv4-mapped IPv6 address. */ memset(&key, 0, sizeof(key)); key.sin6_family = AF_INET6; key.sin6_len = sizeof(key); _map_v4v6_address( (char *)&((struct sockaddr_in *)addr)->sin_addr, (char *)&key.sin6_addr); break; default: return(NULL); } for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { pol = &ent->pc_policy; matchlen = 0; mp = (u_char *)&pol->addrmask.sin6_addr; ep = mp + 16; /* XXX: scope field? */ k = (u_char *)&key.sin6_addr; p = (u_char *)&pol->addr.sin6_addr; for (; mp < ep && *mp; mp++, k++, p++) { m = *mp; if ((*k & m) != *p) goto next; /* not match */ if (m == 0xff) /* short cut for a typical case */ matchlen += 8; else { while (m >= 0x80) { matchlen++; m <<= 1; } } } /* matched. check if this is better than the current best. */ if (matchlen > bestmatchlen) { bestent = ent; bestmatchlen = matchlen; } next: continue; } return(bestent); #else return(NULL); #endif } static void set_source(struct ai_order *aio, struct policyhead *ph) { struct addrinfo ai = *aio->aio_ai; struct sockaddr_storage ss; socklen_t srclen; int s; /* set unspec ("no source is available"), just in case */ aio->aio_srcsa.sa_family = AF_UNSPEC; aio->aio_srcscope = -1; switch(ai.ai_family) { case AF_INET: #ifdef INET6 case AF_INET6: #endif break; default: /* ignore unsupported AFs explicitly */ return; } /* XXX: make a dummy addrinfo to call connect() */ ai.ai_socktype = SOCK_DGRAM; ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ ai.ai_next = NULL; memset(&ss, 0, sizeof(ss)); memcpy(&ss, ai.ai_addr, ai.ai_addrlen); ai.ai_addr = (struct sockaddr *)&ss; get_port(&ai, "1", 0); /* open a socket to get the source address for the given dst */ if ((s = _socket(ai.ai_family, ai.ai_socktype | SOCK_CLOEXEC, ai.ai_protocol)) < 0) return; /* give up */ #ifdef INET6 if (ai.ai_family == AF_INET6) { struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)ai.ai_addr; int off = 0; if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) (void)_setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, (char *)&off, sizeof(off)); } #endif if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) goto cleanup; srclen = ai.ai_addrlen; if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { aio->aio_srcsa.sa_family = AF_UNSPEC; goto cleanup; } aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); #ifdef INET6 if (ai.ai_family == AF_INET6) { struct in6_ifreq ifr6; u_int32_t flags6; memset(&ifr6, 0, sizeof(ifr6)); memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { flags6 = ifr6.ifr_ifru.ifru_flags6; if ((flags6 & IN6_IFF_DEPRECATED)) aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; } } #endif cleanup: _close(s); return; } static int matchlen(struct sockaddr *src, struct sockaddr *dst) { int match = 0; u_char *s, *d; u_char *lim, r; int addrlen; switch (src->sa_family) { #ifdef INET6 case AF_INET6: s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; addrlen = sizeof(struct in6_addr); lim = s + addrlen; break; #endif case AF_INET: s = (u_char *)&((struct sockaddr_in *)src)->sin_addr; d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr; addrlen = sizeof(struct in_addr); lim = s + addrlen; break; default: return(0); } while (s < lim) if ((r = (*d++ ^ *s++)) != 0) { while ((r & 0x80) == 0) { match++; r <<= 1; } break; } else match += 8; return(match); } static int comp_dst(const void *arg1, const void *arg2) { const struct ai_order *dst1 = arg1, *dst2 = arg2; /* * Rule 1: Avoid unusable destinations. * XXX: we currently do not consider if an appropriate route exists. */ if (dst1->aio_srcsa.sa_family != AF_UNSPEC && dst2->aio_srcsa.sa_family == AF_UNSPEC) { return(-1); } if (dst1->aio_srcsa.sa_family == AF_UNSPEC && dst2->aio_srcsa.sa_family != AF_UNSPEC) { return(1); } /* Rule 2: Prefer matching scope. */ if (dst1->aio_dstscope == dst1->aio_srcscope && dst2->aio_dstscope != dst2->aio_srcscope) { return(-1); } if (dst1->aio_dstscope != dst1->aio_srcscope && dst2->aio_dstscope == dst2->aio_srcscope) { return(1); } /* Rule 3: Avoid deprecated addresses. */ if (dst1->aio_srcsa.sa_family != AF_UNSPEC && dst2->aio_srcsa.sa_family != AF_UNSPEC) { if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { return(-1); } if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { return(1); } } /* Rule 4: Prefer home addresses. */ /* XXX: not implemented yet */ /* Rule 5: Prefer matching label. */ #ifdef INET6 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && dst1->aio_srcpolicy->pc_policy.label == dst1->aio_dstpolicy->pc_policy.label && (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || dst2->aio_srcpolicy->pc_policy.label != dst2->aio_dstpolicy->pc_policy.label)) { return(-1); } if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && dst2->aio_srcpolicy->pc_policy.label == dst2->aio_dstpolicy->pc_policy.label && (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || dst1->aio_srcpolicy->pc_policy.label != dst1->aio_dstpolicy->pc_policy.label)) { return(1); } #endif /* Rule 6: Prefer higher precedence. */ #ifdef INET6 if (dst1->aio_dstpolicy && (dst2->aio_dstpolicy == NULL || dst1->aio_dstpolicy->pc_policy.preced > dst2->aio_dstpolicy->pc_policy.preced)) { return(-1); } if (dst2->aio_dstpolicy && (dst1->aio_dstpolicy == NULL || dst2->aio_dstpolicy->pc_policy.preced > dst1->aio_dstpolicy->pc_policy.preced)) { return(1); } #endif /* Rule 7: Prefer native transport. */ /* XXX: not implemented yet */ /* Rule 8: Prefer smaller scope. */ if (dst1->aio_dstscope >= 0 && dst1->aio_dstscope < dst2->aio_dstscope) { return(-1); } if (dst2->aio_dstscope >= 0 && dst2->aio_dstscope < dst1->aio_dstscope) { return(1); } /* * Rule 9: Use longest matching prefix. * We compare the match length in a same AF only. */ if (dst1->aio_ai->ai_addr->sa_family == dst2->aio_ai->ai_addr->sa_family && dst1->aio_ai->ai_addr->sa_family != AF_INET) { if (dst1->aio_matchlen > dst2->aio_matchlen) { return(-1); } if (dst1->aio_matchlen < dst2->aio_matchlen) { return(1); } } /* Rule 10: Otherwise, leave the order unchanged. */ /* * Note that qsort is unstable; so, we can't return zero and * expect the order to be unchanged. * That also means we can't depend on the current position of * dst2 being after dst1. We must enforce the initial order * with an explicit compare on the original position. * The qsort specification requires that "When the same objects * (consisting of width bytes, irrespective of their current * positions in the array) are passed more than once to the * comparison function, the results shall be consistent with one * another." * In other words, If A < B, then we must also return B > A. */ if (dst2->aio_initial_sequence < dst1->aio_initial_sequence) return(1); return(-1); } /* * Copy from scope.c. * XXX: we should standardize the functions and link them as standard * library. */ static int gai_addr2scopetype(struct sockaddr *sa) { #ifdef INET6 struct sockaddr_in6 *sa6; #endif struct sockaddr_in *sa4; switch(sa->sa_family) { #ifdef INET6 case AF_INET6: sa6 = (struct sockaddr_in6 *)sa; if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { /* just use the scope field of the multicast address */ return(sa6->sin6_addr.s6_addr[2] & 0x0f); } /* * Unicast addresses: map scope type to corresponding scope * value defined for multcast addresses. * XXX: hardcoded scope type values are bad... */ if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) return(1); /* node local scope */ if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) return(2); /* link-local scope */ if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) return(5); /* site-local scope */ return(14); /* global scope */ break; #endif case AF_INET: /* * IPv4 pseudo scoping according to RFC 3484. */ sa4 = (struct sockaddr_in *)sa; /* IPv4 autoconfiguration addresses have link-local scope. */ if (((u_char *)&sa4->sin_addr)[0] == 169 && ((u_char *)&sa4->sin_addr)[1] == 254) return(2); /* Private addresses have site-local scope. */ if (((u_char *)&sa4->sin_addr)[0] == 10 || (((u_char *)&sa4->sin_addr)[0] == 172 && (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || (((u_char *)&sa4->sin_addr)[0] == 192 && ((u_char *)&sa4->sin_addr)[1] == 168)) return(14); /* XXX: It should be 5 unless NAT */ /* Loopback addresses have link-local scope. */ if (((u_char *)&sa4->sin_addr)[0] == 127) return(2); return(14); break; default: errno = EAFNOSUPPORT; /* is this a good error? */ return(-1); } } static int explore_copy(const struct addrinfo *pai, const struct addrinfo *src0, struct addrinfo **res) { int error; struct addrinfo sentinel, *cur; const struct addrinfo *src; error = 0; sentinel.ai_next = NULL; cur = &sentinel; for (src = src0; src != NULL; src = src->ai_next) { if (src->ai_family != pai->ai_family) continue; cur->ai_next = copy_ai(src); if (!cur->ai_next) { error = EAI_MEMORY; goto fail; } cur->ai_next->ai_socktype = pai->ai_socktype; cur->ai_next->ai_protocol = pai->ai_protocol; cur = cur->ai_next; } *res = sentinel.ai_next; return 0; fail: freeaddrinfo(sentinel.ai_next); return error; } /* * hostname == NULL. * passive socket -> anyaddr (0.0.0.0 or ::) * non-passive socket -> localhost (127.0.0.1 or ::1) */ static int explore_null(const struct addrinfo *pai, const char *servname, struct addrinfo **res) { int s; const struct afd *afd; struct addrinfo *ai; int error; *res = NULL; ai = NULL; if (pai->ai_family == PF_LOCAL) return (0); /* * filter out AFs that are not supported by the kernel * XXX errno? */ s = _socket(pai->ai_family, SOCK_DGRAM | SOCK_CLOEXEC, 0); if (s < 0) { if (errno != EMFILE) return 0; } else _close(s); afd = find_afd(pai->ai_family); if (afd == NULL) return 0; if (pai->ai_flags & AI_PASSIVE) { GET_AI(ai, afd, afd->a_addrany); GET_PORT(ai, servname); } else { GET_AI(ai, afd, afd->a_loopback); GET_PORT(ai, servname); } *res = ai; return 0; free: if (ai != NULL) freeaddrinfo(ai); return error; } /* * numeric hostname */ static int explore_numeric(const struct addrinfo *pai, const char *hostname, const char *servname, struct addrinfo **res, const char *canonname) { const struct afd *afd; struct addrinfo *ai, ai0; int error; char pton[PTON_MAX], path[PATH_MAX], *p; #ifdef CTASSERT CTASSERT(sizeofmember(struct sockaddr_un, sun_path) <= PATH_MAX); #endif *res = NULL; ai = NULL; afd = find_afd(pai->ai_family); if (afd == NULL) return 0; switch (afd->a_af) { case AF_LOCAL: if (hostname[0] != '/') ERR(EAI_NONAME); if (strlen(hostname) > afd->a_addrlen) ERR(EAI_MEMORY); /* NUL-termination does not need to be guaranteed. */ strncpy(path, hostname, afd->a_addrlen); p = &path[0]; break; case AF_INET: /* * RFC3493 requires getaddrinfo() to accept AF_INET formats * that are accepted by inet_addr() and its family. The * accepted forms includes the "classful" one, which inet_pton * does not accept. So we need to separate the case for * AF_INET. */ if (inet_aton(hostname, (struct in_addr *)pton) != 1) return 0; p = pton; break; default: if (inet_pton(afd->a_af, hostname, pton) != 1) { if (pai->ai_family != AF_INET6 || (pai->ai_flags & AI_V4MAPPED) != AI_V4MAPPED) return 0; if (inet_aton(hostname, (struct in_addr *)pton) != 1) return 0; afd = &afdl[N_INET]; ai0 = *pai; ai0.ai_family = AF_INET; pai = &ai0; } p = pton; break; } if (pai->ai_family == afd->a_af) { GET_AI(ai, afd, p); GET_PORT(ai, servname); if ((pai->ai_family == AF_INET || pai->ai_family == AF_INET6) && (pai->ai_flags & AI_CANONNAME)) { /* * Set the numeric address itself as the canonical * name, based on a clarification in RFC3493. */ GET_CANONNAME(ai, canonname); } } else { /* * XXX: This should not happen since we already matched the AF * by find_afd. */ ERR(EAI_FAMILY); } *res = ai; return 0; free: bad: if (ai != NULL) freeaddrinfo(ai); return error; } /* * numeric hostname with scope */ static int explore_numeric_scope(const struct addrinfo *pai, const char *hostname, const char *servname, struct addrinfo **res) { #if !defined(SCOPE_DELIMITER) || !defined(INET6) return explore_numeric(pai, hostname, servname, res, hostname); #else const struct afd *afd; struct addrinfo *cur; int error; char *cp, *hostname2 = NULL, *scope, *addr; struct sockaddr_in6 *sin6; afd = find_afd(pai->ai_family); if (afd == NULL) return 0; if (!afd->a_scoped) return explore_numeric(pai, hostname, servname, res, hostname); cp = strchr(hostname, SCOPE_DELIMITER); if (cp == NULL) return explore_numeric(pai, hostname, servname, res, hostname); /* * Handle special case of */ hostname2 = strdup(hostname); if (hostname2 == NULL) return EAI_MEMORY; /* terminate at the delimiter */ hostname2[cp - hostname] = '\0'; addr = hostname2; scope = cp + 1; error = explore_numeric(pai, addr, servname, res, hostname); if (error == 0) { u_int32_t scopeid; for (cur = *res; cur; cur = cur->ai_next) { if (cur->ai_family != AF_INET6) continue; sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { free(hostname2); freeaddrinfo(*res); *res = NULL; return(EAI_NONAME); /* XXX: is return OK? */ } sin6->sin6_scope_id = scopeid; } } free(hostname2); if (error && *res) { freeaddrinfo(*res); *res = NULL; } return error; #endif } static int get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str) { if ((pai->ai_flags & AI_CANONNAME) != 0) { ai->ai_canonname = strdup(str); if (ai->ai_canonname == NULL) return EAI_MEMORY; } return 0; } static struct addrinfo * get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr) { char *p; struct addrinfo *ai; #ifdef INET6 struct in6_addr mapaddr; if (afd->a_af == AF_INET && (pai->ai_flags & AI_V4MAPPED) != 0) { afd = &afdl[N_INET6]; _map_v4v6_address(addr, (char *)&mapaddr); addr = (char *)&mapaddr; } #endif ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) + (afd->a_socklen)); if (ai == NULL) return NULL; memcpy(ai, pai, sizeof(struct addrinfo)); ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); memset(ai->ai_addr, 0, (size_t)afd->a_socklen); ai->ai_addr->sa_len = afd->a_socklen; ai->ai_addrlen = afd->a_socklen; if (ai->ai_family == PF_LOCAL) { size_t n = strnlen(addr, afd->a_addrlen); ai->ai_addrlen -= afd->a_addrlen - n; ai->ai_addr->sa_len -= afd->a_addrlen - n; } ai->ai_addr->sa_family = ai->ai_family = afd->a_af; p = (char *)(void *)(ai->ai_addr); memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); return ai; } /* XXX need to malloc() the same way we do from other functions! */ static struct addrinfo * copy_ai(const struct addrinfo *pai) { struct addrinfo *ai; size_t l; l = sizeof(*ai) + pai->ai_addrlen; if ((ai = calloc(1, l)) == NULL) return NULL; memcpy(ai, pai, sizeof(*ai)); ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); memcpy(ai->ai_addr, pai->ai_addr, pai->ai_addrlen); if (pai->ai_canonname) { l = strlen(pai->ai_canonname) + 1; if ((ai->ai_canonname = malloc(l)) == NULL) { free(ai); return NULL; } strlcpy(ai->ai_canonname, pai->ai_canonname, l); } else { /* just to make sure */ ai->ai_canonname = NULL; } ai->ai_next = NULL; return ai; } static int get_portmatch(const struct addrinfo *ai, const char *servname) { /* get_port does not touch first argument when matchonly == 1. */ /* LINTED const cast */ return get_port((struct addrinfo *)ai, servname, 1); } static int get_port(struct addrinfo *ai, const char *servname, int matchonly) { const char *proto; struct servent *sp; int port, error; int allownumeric; if (servname == NULL) return 0; switch (ai->ai_family) { case AF_LOCAL: /* AF_LOCAL ignores servname silently. */ return (0); case AF_INET: #ifdef AF_INET6 case AF_INET6: #endif break; default: return 0; } switch (ai->ai_socktype) { case SOCK_RAW: return EAI_SERVICE; case SOCK_DGRAM: case SOCK_STREAM: case SOCK_SEQPACKET: allownumeric = 1; break; case ANY: switch (ai->ai_family) { case AF_INET: #ifdef AF_INET6 case AF_INET6: #endif allownumeric = 1; break; default: allownumeric = 0; break; } break; default: return EAI_SOCKTYPE; } error = str2number(servname, &port); if (error == 0) { if (!allownumeric) return EAI_SERVICE; if (port < 0 || port > 65535) return EAI_SERVICE; port = htons(port); } else { if (ai->ai_flags & AI_NUMERICSERV) return EAI_NONAME; switch (ai->ai_protocol) { case IPPROTO_UDP: proto = "udp"; break; case IPPROTO_TCP: proto = "tcp"; break; case IPPROTO_SCTP: proto = "sctp"; break; case IPPROTO_UDPLITE: proto = "udplite"; break; default: proto = NULL; break; } if ((sp = getservbyname(servname, proto)) == NULL) return EAI_SERVICE; port = sp->s_port; } if (!matchonly) { switch (ai->ai_family) { case AF_INET: ((struct sockaddr_in *)(void *) ai->ai_addr)->sin_port = port; break; #ifdef INET6 case AF_INET6: ((struct sockaddr_in6 *)(void *) ai->ai_addr)->sin6_port = port; break; #endif } } return 0; } static const struct afd * find_afd(int af) { const struct afd *afd; if (af == PF_UNSPEC) return NULL; for (afd = afdl; afd->a_af; afd++) { if (afd->a_af == af) return afd; } return NULL; } /* * RFC 3493: AI_ADDRCONFIG check. Determines which address families are * configured on the local system and correlates with pai->ai_family value. * If an address family is not configured on the system, it will not be * queried for. For this purpose, loopback addresses are not considered * configured addresses. * * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with * _dns_getaddrinfo. */ static int addrconfig(struct addrinfo *pai) { struct ifaddrs *ifaddrs, *ifa; struct sockaddr_in *sin; #ifdef INET6 struct sockaddr_in6 *sin6; #endif int seen_inet = 0, seen_inet6 = 0; if (getifaddrs(&ifaddrs) != 0) return (0); for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) { if (ifa->ifa_addr == NULL || (ifa->ifa_flags & IFF_UP) == 0) continue; switch (ifa->ifa_addr->sa_family) { case AF_INET: if (seen_inet) continue; sin = (struct sockaddr_in *)(ifa->ifa_addr); if (htonl(sin->sin_addr.s_addr) == INADDR_LOOPBACK) continue; seen_inet = 1; break; #ifdef INET6 case AF_INET6: if (seen_inet6) continue; sin6 = (struct sockaddr_in6 *)(ifa->ifa_addr); if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr)) continue; if ((ifa->ifa_flags & IFT_LOOP) != 0 && IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) continue; if (is_ifdisabled(ifa->ifa_name)) continue; seen_inet6 = 1; break; #endif } } freeifaddrs(ifaddrs); switch(pai->ai_family) { case AF_INET6: return (seen_inet6); case AF_INET: return (seen_inet); case AF_UNSPEC: if (seen_inet == seen_inet6) return (seen_inet); pai->ai_family = seen_inet ? AF_INET : AF_INET6; return (1); } return (1); } #ifdef INET6 static int is_ifdisabled(char *name) { struct in6_ndireq nd; int fd; if ((fd = _socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, 0)) < 0) return (-1); memset(&nd, 0, sizeof(nd)); strlcpy(nd.ifname, name, sizeof(nd.ifname)); if (_ioctl(fd, SIOCGIFINFO_IN6, &nd) < 0) { _close(fd); return (-1); } _close(fd); return ((nd.ndi.flags & ND6_IFF_IFDISABLED) != 0); } /* convert a string to a scope identifier. XXX: IPv6 specific */ static int ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid) { u_long lscopeid; struct in6_addr *a6; char *ep; a6 = &sin6->sin6_addr; /* empty scopeid portion is invalid */ if (*scope == '\0') return -1; if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6) || IN6_IS_ADDR_MC_NODELOCAL(a6)) { /* * We currently assume a one-to-one mapping between links * and interfaces, so we simply use interface indices for * like-local scopes. */ *scopeid = if_nametoindex(scope); if (*scopeid == 0) goto trynumeric; return 0; } /* still unclear about literal, allow numeric only - placeholder */ if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) goto trynumeric; if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) goto trynumeric; else goto trynumeric; /* global */ /* try to convert to a numeric id as a last resort */ trynumeric: errno = 0; lscopeid = strtoul(scope, &ep, 10); *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) return 0; else return -1; } #endif #ifdef NS_CACHING static int addrinfo_id_func(char *buffer, size_t *buffer_size, va_list ap, void *cache_mdata) { res_state statp; u_long res_options; const int op_id = 0; /* identifies the getaddrinfo for the cache */ char *hostname; struct addrinfo *hints; char *p; int ai_flags, ai_family, ai_socktype, ai_protocol; size_t desired_size, size; statp = __res_state(); res_options = statp->options & (RES_RECURSE | RES_DEFNAMES | RES_DNSRCH | RES_NOALIASES | RES_USE_INET6); hostname = va_arg(ap, char *); hints = va_arg(ap, struct addrinfo *); desired_size = sizeof(res_options) + sizeof(int) + sizeof(int) * 4; if (hostname != NULL) { size = strlen(hostname); desired_size += size + 1; } else size = 0; if (desired_size > *buffer_size) { *buffer_size = desired_size; return (NS_RETURN); } if (hints == NULL) ai_flags = ai_family = ai_socktype = ai_protocol = 0; else { ai_flags = hints->ai_flags; ai_family = hints->ai_family; ai_socktype = hints->ai_socktype; ai_protocol = hints->ai_protocol; } p = buffer; memcpy(p, &res_options, sizeof(res_options)); p += sizeof(res_options); memcpy(p, &op_id, sizeof(int)); p += sizeof(int); memcpy(p, &ai_flags, sizeof(int)); p += sizeof(int); memcpy(p, &ai_family, sizeof(int)); p += sizeof(int); memcpy(p, &ai_socktype, sizeof(int)); p += sizeof(int); memcpy(p, &ai_protocol, sizeof(int)); p += sizeof(int); if (hostname != NULL) memcpy(p, hostname, size); *buffer_size = desired_size; return (NS_SUCCESS); } static int addrinfo_marshal_func(char *buffer, size_t *buffer_size, void *retval, va_list ap, void *cache_mdata) { struct addrinfo *ai, *cai; char *p; size_t desired_size, size, ai_size; ai = *((struct addrinfo **)retval); desired_size = sizeof(size_t); ai_size = 0; for (cai = ai; cai != NULL; cai = cai->ai_next) { desired_size += sizeof(struct addrinfo) + cai->ai_addrlen; if (cai->ai_canonname != NULL) desired_size += sizeof(size_t) + strlen(cai->ai_canonname); ++ai_size; } if (desired_size > *buffer_size) { /* this assignment is here for future use */ errno = ERANGE; *buffer_size = desired_size; return (NS_RETURN); } memset(buffer, 0, desired_size); p = buffer; memcpy(p, &ai_size, sizeof(size_t)); p += sizeof(size_t); for (cai = ai; cai != NULL; cai = cai->ai_next) { memcpy(p, cai, sizeof(struct addrinfo)); p += sizeof(struct addrinfo); memcpy(p, cai->ai_addr, cai->ai_addrlen); p += cai->ai_addrlen; if (cai->ai_canonname != NULL) { size = strlen(cai->ai_canonname); memcpy(p, &size, sizeof(size_t)); p += sizeof(size_t); memcpy(p, cai->ai_canonname, size); p += size; } } return (NS_SUCCESS); } static int addrinfo_unmarshal_func(char *buffer, size_t buffer_size, void *retval, va_list ap, void *cache_mdata) { struct addrinfo new_ai, *result, *sentinel, *lasts; char *p; size_t ai_size, ai_i, size; p = buffer; memcpy(&ai_size, p, sizeof(size_t)); p += sizeof(size_t); result = NULL; lasts = NULL; for (ai_i = 0; ai_i < ai_size; ++ai_i) { memcpy(&new_ai, p, sizeof(struct addrinfo)); p += sizeof(struct addrinfo); size = new_ai.ai_addrlen + sizeof(struct addrinfo) + _ALIGNBYTES; sentinel = calloc(1, size); memcpy(sentinel, &new_ai, sizeof(struct addrinfo)); sentinel->ai_addr = (struct sockaddr *)_ALIGN((char *)sentinel + sizeof(struct addrinfo)); memcpy(sentinel->ai_addr, p, new_ai.ai_addrlen); p += new_ai.ai_addrlen; if (new_ai.ai_canonname != NULL) { memcpy(&size, p, sizeof(size_t)); p += sizeof(size_t); sentinel->ai_canonname = calloc(1, size + 1); memcpy(sentinel->ai_canonname, p, size); p += size; } if (result == NULL) { result = sentinel; lasts = sentinel; } else { lasts->ai_next = sentinel; lasts = sentinel; } } *((struct addrinfo **)retval) = result; return (NS_SUCCESS); } #endif /* NS_CACHING */ /* * FQDN hostname, DNS lookup */ static int explore_fqdn(const struct addrinfo *pai, const char *hostname, const char *servname, struct addrinfo **res) { struct addrinfo *result; struct addrinfo *cur; int error = 0; #ifdef NS_CACHING static const nss_cache_info cache_info = NS_COMMON_CACHE_INFO_INITIALIZER( hosts, NULL, addrinfo_id_func, addrinfo_marshal_func, addrinfo_unmarshal_func); #endif static const ns_dtab dtab[] = { NS_FILES_CB(_files_getaddrinfo, NULL) { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ NS_NIS_CB(_yp_getaddrinfo, NULL) #ifdef NS_CACHING NS_CACHE_CB(&cache_info) #endif { 0 } }; result = NULL; /* * if the servname does not match socktype/protocol, ignore it. */ if (get_portmatch(pai, servname) != 0) return 0; switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", default_dns_files, hostname, pai)) { case NS_TRYAGAIN: error = EAI_AGAIN; goto free; case NS_UNAVAIL: error = EAI_FAIL; goto free; case NS_NOTFOUND: error = EAI_NONAME; goto free; case NS_SUCCESS: error = 0; for (cur = result; cur; cur = cur->ai_next) { GET_PORT(cur, servname); /* canonname should be filled already */ } break; } *res = result; return 0; free: if (result) freeaddrinfo(result); return error; } #ifdef DEBUG static const char AskedForGot[] = "gethostby*.getanswer: asked for \"%s\", got \"%s\""; #endif static struct addrinfo * getanswer(const querybuf *answer, int anslen, const char *qname, int qtype, const struct addrinfo *pai, res_state res) { struct addrinfo sentinel, *cur; struct addrinfo ai; const struct afd *afd; char *canonname; const HEADER *hp; const u_char *cp; int n; const u_char *eom; char *bp, *ep; int type, class, ancount, qdcount; int haveanswer, had_error; char tbuf[MAXDNAME]; int (*name_ok)(const char *); char hostbuf[8*1024]; memset(&sentinel, 0, sizeof(sentinel)); cur = &sentinel; canonname = NULL; eom = answer->buf + anslen; switch (qtype) { case T_A: case T_AAAA: case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ name_ok = res_hnok; break; default: return (NULL); /* XXX should be abort(); */ } /* * find first satisfactory answer */ hp = &answer->hdr; ancount = ntohs(hp->ancount); qdcount = ntohs(hp->qdcount); bp = hostbuf; ep = hostbuf + sizeof hostbuf; cp = answer->buf + HFIXEDSZ; if (qdcount != 1) { RES_SET_H_ERRNO(res, NO_RECOVERY); return (NULL); } n = dn_expand(answer->buf, eom, cp, bp, ep - bp); if ((n < 0) || !(*name_ok)(bp)) { RES_SET_H_ERRNO(res, NO_RECOVERY); return (NULL); } cp += n + QFIXEDSZ; if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { /* res_send() has already verified that the query name is the * same as the one we sent; this just gets the expanded name * (i.e., with the succeeding search-domain tacked on). */ n = strlen(bp) + 1; /* for the \0 */ if (n >= MAXHOSTNAMELEN) { RES_SET_H_ERRNO(res, NO_RECOVERY); return (NULL); } canonname = bp; bp += n; /* The qname can be abbreviated, but h_name is now absolute. */ qname = canonname; } haveanswer = 0; had_error = 0; while (ancount-- > 0 && cp < eom && !had_error) { n = dn_expand(answer->buf, eom, cp, bp, ep - bp); if ((n < 0) || !(*name_ok)(bp)) { had_error++; continue; } cp += n; /* name */ type = _getshort(cp); cp += INT16SZ; /* type */ class = _getshort(cp); cp += INT16SZ + INT32SZ; /* class, TTL */ n = _getshort(cp); cp += INT16SZ; /* len */ if (class != C_IN) { /* XXX - debug? syslog? */ cp += n; continue; /* XXX - had_error++ ? */ } if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && type == T_CNAME) { n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); if ((n < 0) || !(*name_ok)(tbuf)) { had_error++; continue; } cp += n; /* Get canonical name. */ n = strlen(tbuf) + 1; /* for the \0 */ if (n > ep - bp || n >= MAXHOSTNAMELEN) { had_error++; continue; } strlcpy(bp, tbuf, ep - bp); canonname = bp; bp += n; continue; } if (qtype == T_ANY) { if (!(type == T_A || type == T_AAAA)) { cp += n; continue; } } else if (type != qtype) { #ifdef DEBUG if (type != T_KEY && type != T_SIG && type != ns_t_dname) syslog(LOG_NOTICE|LOG_AUTH, "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", qname, p_class(C_IN), p_type(qtype), p_type(type)); #endif cp += n; continue; /* XXX - had_error++ ? */ } switch (type) { case T_A: case T_AAAA: if (strcasecmp(canonname, bp) != 0) { #ifdef DEBUG syslog(LOG_NOTICE|LOG_AUTH, AskedForGot, canonname, bp); #endif cp += n; continue; /* XXX - had_error++ ? */ } if (type == T_A && n != INADDRSZ) { cp += n; continue; } if (type == T_AAAA && n != IN6ADDRSZ) { cp += n; continue; } #ifdef FILTER_V4MAPPED if (type == T_AAAA) { struct in6_addr in6; memcpy(&in6, cp, sizeof(in6)); if (IN6_IS_ADDR_V4MAPPED(&in6)) { cp += n; continue; } } #endif if (!haveanswer) { int nn; canonname = bp; nn = strlen(bp) + 1; /* for the \0 */ bp += nn; } /* don't overwrite pai */ ai = *pai; ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; afd = find_afd(ai.ai_family); if (afd == NULL) { cp += n; continue; } cur->ai_next = get_ai(&ai, afd, (const char *)cp); if (cur->ai_next == NULL) had_error++; while (cur && cur->ai_next) cur = cur->ai_next; cp += n; break; default: abort(); } if (!had_error) haveanswer++; } if (haveanswer) { #if defined(RESOLVSORT) /* * We support only IPv4 address for backward * compatibility against gethostbyname(3). */ if (res->nsort && qtype == T_A) { if (addr4sort(&sentinel, res) < 0) { freeaddrinfo(sentinel.ai_next); RES_SET_H_ERRNO(res, NO_RECOVERY); return NULL; } } #endif /*RESOLVSORT*/ if (!canonname) (void)get_canonname(pai, sentinel.ai_next, qname); else (void)get_canonname(pai, sentinel.ai_next, canonname); RES_SET_H_ERRNO(res, NETDB_SUCCESS); return sentinel.ai_next; } /* * We could have walked a CNAME chain, but the ultimate target * may not have what we looked for. */ RES_SET_H_ERRNO(res, ntohs(hp->ancount) > 0 ? NO_DATA : NO_RECOVERY); return NULL; } #ifdef RESOLVSORT struct addr_ptr { struct addrinfo *ai; int aval; }; static int addr4sort(struct addrinfo *sentinel, res_state res) { struct addrinfo *ai; struct addr_ptr *addrs, addr; struct sockaddr_in *sin; int naddrs, i, j; int needsort = 0; if (!sentinel) return -1; naddrs = 0; for (ai = sentinel->ai_next; ai; ai = ai->ai_next) naddrs++; if (naddrs < 2) return 0; /* We don't need sorting. */ if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) return -1; i = 0; for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { sin = (struct sockaddr_in *)ai->ai_addr; for (j = 0; (unsigned)j < res->nsort; j++) { if (res->sort_list[j].addr.s_addr == (sin->sin_addr.s_addr & res->sort_list[j].mask)) break; } addrs[i].ai = ai; addrs[i].aval = j; if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) needsort = i; i++; } if (!needsort) { free(addrs); return 0; } while (needsort < naddrs) { for (j = needsort - 1; j >= 0; j--) { if (addrs[j].aval > addrs[j+1].aval) { addr = addrs[j]; addrs[j] = addrs[j + 1]; addrs[j + 1] = addr; } else break; } needsort++; } ai = sentinel; for (i = 0; i < naddrs; ++i) { ai->ai_next = addrs[i].ai; ai = ai->ai_next; } ai->ai_next = NULL; free(addrs); return 0; } #endif /*RESOLVSORT*/ /*ARGSUSED*/ static int _dns_getaddrinfo(void *rv, void *cb_data, va_list ap) { struct addrinfo *ai, ai0; querybuf *buf, *buf2; const char *hostname; const struct addrinfo *pai; struct addrinfo sentinel, *cur; struct res_target q, q2; res_state res; ai = NULL; hostname = va_arg(ap, char *); pai = va_arg(ap, const struct addrinfo *); memset(&q, 0, sizeof(q)); memset(&q2, 0, sizeof(q2)); memset(&sentinel, 0, sizeof(sentinel)); cur = &sentinel; res = __res_state(); buf = malloc(sizeof(*buf)); if (!buf) { RES_SET_H_ERRNO(res, NETDB_INTERNAL); return NS_NOTFOUND; } buf2 = malloc(sizeof(*buf2)); if (!buf2) { free(buf); RES_SET_H_ERRNO(res, NETDB_INTERNAL); return NS_NOTFOUND; } if (pai->ai_family == AF_INET6 && (pai->ai_flags & AI_V4MAPPED) == AI_V4MAPPED) { ai0 = *pai; ai0.ai_family = AF_UNSPEC; pai = &ai0; } switch (pai->ai_family) { case AF_UNSPEC: q.name = hostname; q.qclass = C_IN; q.qtype = T_A; q.answer = buf->buf; q.anslen = sizeof(buf->buf); q.next = &q2; q2.name = hostname; q2.qclass = C_IN; q2.qtype = T_AAAA; q2.answer = buf2->buf; q2.anslen = sizeof(buf2->buf); break; case AF_INET: q.name = hostname; q.qclass = C_IN; q.qtype = T_A; q.answer = buf->buf; q.anslen = sizeof(buf->buf); break; case AF_INET6: q.name = hostname; q.qclass = C_IN; q.qtype = T_AAAA; q.answer = buf->buf; q.anslen = sizeof(buf->buf); break; default: free(buf); free(buf2); return NS_UNAVAIL; } if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) { RES_SET_H_ERRNO(res, NETDB_INTERNAL); free(buf); free(buf2); return NS_NOTFOUND; } if (res_searchN(hostname, &q, res) < 0) { free(buf); free(buf2); return NS_NOTFOUND; } /* prefer IPv6 */ if (q.next) { ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res); if (ai != NULL) { cur->ai_next = ai; while (cur && cur->ai_next) cur = cur->ai_next; } } if (ai == NULL || pai->ai_family != AF_UNSPEC || (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) != AI_V4MAPPED) { ai = getanswer(buf, q.n, q.name, q.qtype, pai, res); if (ai != NULL) cur->ai_next = ai; } free(buf); free(buf2); if (sentinel.ai_next == NULL) switch (res->res_h_errno) { case HOST_NOT_FOUND: case NO_DATA: return NS_NOTFOUND; case TRY_AGAIN: return NS_TRYAGAIN; default: return NS_UNAVAIL; } *((struct addrinfo **)rv) = sentinel.ai_next; return NS_SUCCESS; } static void _sethtent(FILE **hostf) { if (!*hostf) *hostf = fopen(_PATH_HOSTS, "re"); else rewind(*hostf); } static void _endhtent(FILE **hostf) { if (*hostf) { (void) fclose(*hostf); *hostf = NULL; } } static struct addrinfo * _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) { char *p; char *cp, *tname, *cname; struct addrinfo hints, *res0, *res; int error; const char *addr; char hostbuf[8*1024]; if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "re"))) return (NULL); again: if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) return (NULL); if (*p == '#') goto again; cp = strpbrk(p, "#\n"); if (cp != NULL) *cp = '\0'; if (!(cp = strpbrk(p, " \t"))) goto again; *cp++ = '\0'; addr = p; cname = NULL; /* if this is not something we're looking for, skip it. */ while (cp && *cp) { if (*cp == ' ' || *cp == '\t') { cp++; continue; } tname = cp; if (cname == NULL) cname = cp; if ((cp = strpbrk(cp, " \t")) != NULL) *cp++ = '\0'; if (strcasecmp(name, tname) == 0) goto found; } goto again; found: /* we should not glob socktype/protocol here */ memset(&hints, 0, sizeof(hints)); hints.ai_family = pai->ai_family; hints.ai_socktype = SOCK_DGRAM; hints.ai_protocol = 0; hints.ai_flags = AI_NUMERICHOST; if (pai->ai_family == AF_INET6 && (pai->ai_flags & AI_V4MAPPED) == AI_V4MAPPED) hints.ai_flags |= AI_V4MAPPED; error = getaddrinfo(addr, "0", &hints, &res0); if (error) goto again; #ifdef FILTER_V4MAPPED /* XXX should check all items in the chain */ if (res0->ai_family == AF_INET6 && IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { freeaddrinfo(res0); goto again; } #endif for (res = res0; res; res = res->ai_next) { /* cover it up */ res->ai_flags = pai->ai_flags; res->ai_socktype = pai->ai_socktype; res->ai_protocol = pai->ai_protocol; if (pai->ai_flags & AI_CANONNAME) { if (get_canonname(pai, res, cname) != 0) { freeaddrinfo(res0); goto again; } } } return res0; } static struct addrinfo * _getht(FILE **hostf, const char *name, const struct addrinfo *pai, struct addrinfo *cur) { struct addrinfo *p; while ((p = _gethtent(hostf, name, pai)) != NULL) { cur->ai_next = p; while (cur && cur->ai_next) cur = cur->ai_next; } return (cur); } /*ARGSUSED*/ static int _files_getaddrinfo(void *rv, void *cb_data, va_list ap) { const char *name; const struct addrinfo *pai; struct addrinfo sentinel, *cur; FILE *hostf = NULL; name = va_arg(ap, char *); pai = va_arg(ap, struct addrinfo *); memset(&sentinel, 0, sizeof(sentinel)); cur = &sentinel; _sethtent(&hostf); if (pai->ai_family == AF_INET6 && (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) == AI_V4MAPPED) { struct addrinfo ai0 = *pai; ai0.ai_flags &= ~AI_V4MAPPED; cur = _getht(&hostf, name, &ai0, cur); if (sentinel.ai_next == NULL) { _sethtent(&hostf); ai0.ai_flags |= AI_V4MAPPED; cur = _getht(&hostf, name, &ai0, cur); } } else cur = _getht(&hostf, name, pai, cur); _endhtent(&hostf); *((struct addrinfo **)rv) = sentinel.ai_next; if (sentinel.ai_next == NULL) return NS_NOTFOUND; return NS_SUCCESS; } #ifdef YP /*ARGSUSED*/ static struct addrinfo * _yphostent(char *line, const struct addrinfo *pai) { struct addrinfo sentinel, *cur; struct addrinfo hints, *res, *res0; int error; char *p = line; const char *addr, *canonname; char *nextline; char *cp; addr = canonname = NULL; memset(&sentinel, 0, sizeof(sentinel)); cur = &sentinel; nextline: /* terminate line */ cp = strchr(p, '\n'); if (cp) { *cp++ = '\0'; nextline = cp; } else nextline = NULL; cp = strpbrk(p, " \t"); if (cp == NULL) { if (canonname == NULL) return (NULL); else goto done; } *cp++ = '\0'; addr = p; while (cp && *cp) { if (*cp == ' ' || *cp == '\t') { cp++; continue; } if (!canonname) canonname = cp; if ((cp = strpbrk(cp, " \t")) != NULL) *cp++ = '\0'; } hints = *pai; hints.ai_flags = AI_NUMERICHOST; if (pai->ai_family == AF_INET6 && (pai->ai_flags & AI_V4MAPPED) == AI_V4MAPPED) hints.ai_flags |= AI_V4MAPPED; error = getaddrinfo(addr, NULL, &hints, &res0); if (error == 0) { for (res = res0; res; res = res->ai_next) { /* cover it up */ res->ai_flags = pai->ai_flags; if (pai->ai_flags & AI_CANONNAME) (void)get_canonname(pai, res, canonname); } } else res0 = NULL; if (res0) { cur->ai_next = res0; while (cur && cur->ai_next) cur = cur->ai_next; } if (nextline) { p = nextline; goto nextline; } done: return sentinel.ai_next; } /*ARGSUSED*/ static int _yp_getaddrinfo(void *rv, void *cb_data, va_list ap) { struct addrinfo sentinel, *cur; struct addrinfo *ai = NULL; char *ypbuf; int ypbuflen, r; const char *name; const struct addrinfo *pai; char *ypdomain; if (_yp_check(&ypdomain) == 0) return NS_UNAVAIL; name = va_arg(ap, char *); pai = va_arg(ap, const struct addrinfo *); memset(&sentinel, 0, sizeof(sentinel)); cur = &sentinel; /* ipnodes.byname can hold both IPv4/v6 */ r = yp_match(ypdomain, "ipnodes.byname", name, (int)strlen(name), &ypbuf, &ypbuflen); if (r == 0) { ai = _yphostent(ypbuf, pai); if (ai) { cur->ai_next = ai; while (cur && cur->ai_next) cur = cur->ai_next; } free(ypbuf); } if (ai != NULL) { struct sockaddr_in6 *sin6; switch (ai->ai_family) { case AF_INET: goto done; case AF_INET6: sin6 = (struct sockaddr_in6 *)ai->ai_addr; if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) goto done; break; } } /* hosts.byname is only for IPv4 (Solaris8) */ if (pai->ai_family == AF_UNSPEC || pai->ai_family == AF_INET || ((pai->ai_family == AF_INET6 && (pai->ai_flags & AI_V4MAPPED) == AI_V4MAPPED) && (ai == NULL || (pai->ai_flags & AI_ALL) == AI_ALL))) { r = yp_match(ypdomain, "hosts.byname", name, (int)strlen(name), &ypbuf, &ypbuflen); if (r == 0) { struct addrinfo ai4; ai4 = *pai; if (pai->ai_family == AF_UNSPEC) ai4.ai_family = AF_INET; ai = _yphostent(ypbuf, &ai4); if (ai) { cur->ai_next = ai; while (cur && cur->ai_next) cur = cur->ai_next; } free(ypbuf); } } done: if (sentinel.ai_next == NULL) { RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND); return NS_NOTFOUND; } *((struct addrinfo **)rv) = sentinel.ai_next; return NS_SUCCESS; } #endif /* resolver logic */ /* * Formulate a normal query, send, and await answer. * Returned answer is placed in supplied buffer "answer". * Perform preliminary check of answer, returning success only * if no error is indicated and the answer count is nonzero. * Return the size of the response on success, -1 on error. * Error number is left in h_errno. * * Caller must parse answer and determine whether it answers the question. */ static int res_queryN(const char *name, struct res_target *target, res_state res) { u_char *buf; HEADER *hp; int n; u_int oflags; struct res_target *t; int rcode; int ancount; rcode = NOERROR; ancount = 0; buf = malloc(MAXPACKET); if (!buf) { RES_SET_H_ERRNO(res, NETDB_INTERNAL); return -1; } for (t = target; t; t = t->next) { int class, type; u_char *answer; int anslen; hp = (HEADER *)(void *)t->answer; /* make it easier... */ class = t->qclass; type = t->qtype; answer = t->answer; anslen = t->anslen; oflags = res->_flags; again: hp->rcode = NOERROR; /* default */ #ifdef DEBUG if (res->options & RES_DEBUG) printf(";; res_query(%s, %d, %d)\n", name, class, type); #endif n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL, buf, MAXPACKET); if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 && (res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U) n = res_nopt(res, n, buf, MAXPACKET, anslen); if (n <= 0) { #ifdef DEBUG if (res->options & RES_DEBUG) printf(";; res_query: mkquery failed\n"); #endif free(buf); RES_SET_H_ERRNO(res, NO_RECOVERY); return (n); } n = res_nsend(res, buf, n, answer, anslen); if (n < 0) { /* * if the query choked with EDNS0, retry * without EDNS0 */ if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U && ((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) { res->_flags |= RES_F_EDNS0ERR; if (res->options & RES_DEBUG) printf(";; res_nquery: retry without EDNS0\n"); goto again; } rcode = hp->rcode; /* record most recent error */ #ifdef DEBUG if (res->options & RES_DEBUG) printf(";; res_query: send error\n"); #endif continue; } if (n > anslen) hp->rcode = FORMERR; /* XXX not very informative */ if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { rcode = hp->rcode; /* record most recent error */ #ifdef DEBUG if (res->options & RES_DEBUG) printf(";; rcode = %u, ancount=%u\n", hp->rcode, ntohs(hp->ancount)); #endif continue; } ancount += ntohs(hp->ancount); t->n = n; } free(buf); if (ancount == 0) { switch (rcode) { case NXDOMAIN: RES_SET_H_ERRNO(res, HOST_NOT_FOUND); break; case SERVFAIL: RES_SET_H_ERRNO(res, TRY_AGAIN); break; case NOERROR: RES_SET_H_ERRNO(res, NO_DATA); break; case FORMERR: case NOTIMP: case REFUSED: default: RES_SET_H_ERRNO(res, NO_RECOVERY); break; } return (-1); } return (ancount); } /* * Formulate a normal query, send, and retrieve answer in supplied buffer. * Return the size of the response on success, -1 on error. * If enabled, implement search rules until answer or unrecoverable failure * is detected. Error code, if any, is left in h_errno. */ static int res_searchN(const char *name, struct res_target *target, res_state res) { const char *cp, * const *domain; HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ u_int dots; int trailing_dot, ret, saved_herrno; int got_nodata = 0, got_servfail = 0, root_on_list = 0; int tried_as_is = 0; int searched = 0; char abuf[MAXDNAME]; errno = 0; RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */ dots = 0; for (cp = name; *cp; cp++) dots += (*cp == '.'); trailing_dot = 0; if (cp > name && *--cp == '.') trailing_dot++; /* * if there aren't any dots, it could be a user-level alias */ if (!dots && (cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL) return (res_queryN(cp, target, res)); /* * If there are enough dots in the name, let's just give it a * try 'as is'. The threshold can be set with the "ndots" option. * Also, query 'as is', if there is a trailing dot in the name. */ saved_herrno = -1; if (dots >= res->ndots || trailing_dot) { ret = res_querydomainN(name, NULL, target, res); if (ret > 0 || trailing_dot) return (ret); if (errno == ECONNREFUSED) { RES_SET_H_ERRNO(res, TRY_AGAIN); return (-1); } switch (res->res_h_errno) { case NO_DATA: case HOST_NOT_FOUND: break; case TRY_AGAIN: if (hp->rcode == SERVFAIL) break; /* FALLTHROUGH */ default: return (-1); } saved_herrno = res->res_h_errno; tried_as_is++; } /* * We do at least one level of search if * - there is no dot and RES_DEFNAME is set, or * - there is at least one dot, there is no trailing dot, * and RES_DNSRCH is set. */ if ((!dots && (res->options & RES_DEFNAMES)) || (dots && !trailing_dot && (res->options & RES_DNSRCH))) { int done = 0; for (domain = (const char * const *)res->dnsrch; *domain && !done; domain++) { searched = 1; if (domain[0][0] == '\0' || (domain[0][0] == '.' && domain[0][1] == '\0')) root_on_list++; if (root_on_list && tried_as_is) continue; ret = res_querydomainN(name, *domain, target, res); if (ret > 0) return (ret); /* * If no server present, give up. * If name isn't found in this domain, * keep trying higher domains in the search list * (if that's enabled). * On a NO_DATA error, keep trying, otherwise * a wildcard entry of another type could keep us * from finding this entry higher in the domain. * If we get some other error (negative answer or * server failure), then stop searching up, * but try the input name below in case it's * fully-qualified. */ if (errno == ECONNREFUSED) { RES_SET_H_ERRNO(res, TRY_AGAIN); return (-1); } switch (res->res_h_errno) { case NO_DATA: got_nodata++; /* FALLTHROUGH */ case HOST_NOT_FOUND: /* keep trying */ break; case TRY_AGAIN: got_servfail++; if (hp->rcode == SERVFAIL) { /* try next search element, if any */ break; } /* FALLTHROUGH */ default: /* anything else implies that we're done */ done++; } /* * if we got here for some reason other than DNSRCH, * we only wanted one iteration of the loop, so stop. */ if (!(res->options & RES_DNSRCH)) done++; } } switch (res->res_h_errno) { case NO_DATA: case HOST_NOT_FOUND: break; case TRY_AGAIN: if (hp->rcode == SERVFAIL) break; /* FALLTHROUGH */ default: goto giveup; } /* * If the query has not already been tried as is then try it * unless RES_NOTLDQUERY is set and there were no dots. */ if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) && !(tried_as_is || root_on_list)) { ret = res_querydomainN(name, NULL, target, res); if (ret > 0) return (ret); } /* * if we got here, we didn't satisfy the search. * if we did an initial full query, return that query's h_errno * (note that we wouldn't be here if that query had succeeded). * else if we ever got a nodata, send that back as the reason. * else send back meaningless h_errno, that being the one from * the last DNSRCH we did. */ giveup: if (saved_herrno != -1) RES_SET_H_ERRNO(res, saved_herrno); else if (got_nodata) RES_SET_H_ERRNO(res, NO_DATA); else if (got_servfail) RES_SET_H_ERRNO(res, TRY_AGAIN); return (-1); } /* * Perform a call on res_query on the concatenation of name and domain, * removing a trailing dot from name if domain is NULL. */ static int res_querydomainN(const char *name, const char *domain, struct res_target *target, res_state res) { char nbuf[MAXDNAME]; const char *longname = nbuf; size_t n, d; #ifdef DEBUG if (res->options & RES_DEBUG) printf(";; res_querydomain(%s, %s)\n", name, domain?domain:""); #endif if (domain == NULL) { /* * Check for trailing '.'; * copy without '.' if present. */ n = strlen(name); if (n >= MAXDNAME) { RES_SET_H_ERRNO(res, NO_RECOVERY); return (-1); } if (n > 0 && name[--n] == '.') { strncpy(nbuf, name, n); nbuf[n] = '\0'; } else longname = name; } else { n = strlen(name); d = strlen(domain); if (n + d + 1 >= MAXDNAME) { RES_SET_H_ERRNO(res, NO_RECOVERY); return (-1); } snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); } return (res_queryN(longname, target, res)); }