/* $NetBSD: getaddrinfo.c,v 1.4 2019/02/24 20:01:31 christos Exp $ */
/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
/*! \file */
/**
* getaddrinfo() is used to get a list of IP addresses and port
* numbers for host hostname and service servname as defined in RFC3493.
* hostname and servname are pointers to null-terminated strings
* or NULL. hostname is either a host name or a numeric host address
* string: a dotted decimal IPv4 address or an IPv6 address. servname is
* either a decimal port number or a service name as listed in
* /etc/services.
*
* If the operating system does not provide a struct addrinfo, the
* following structure is used:
*
* \code
* struct addrinfo {
* int ai_flags; // AI_PASSIVE, AI_CANONNAME
* int ai_family; // PF_xxx
* int ai_socktype; // SOCK_xxx
* int ai_protocol; // 0 or IPPROTO_xxx for IPv4 and IPv6
* size_t ai_addrlen; // length of ai_addr
* char *ai_canonname; // canonical name for hostname
* struct sockaddr *ai_addr; // binary address
* struct addrinfo *ai_next; // next structure in linked list
* };
* \endcode
*
*
* hints is an optional pointer to a struct addrinfo. 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 *hints:
*
* <ul>
* <li>ai_family:
* The protocol family that should be used. When ai_family is set
* to PF_UNSPEC, it means the caller will accept any protocol
* family supported by the operating system.</li>
*
* <li>ai_socktype:
* denotes the type of socket -- SOCK_STREAM, SOCK_DGRAM or
* SOCK_RAW -- that is wanted. When ai_socktype is zero the caller
* will accept any socket type.</li>
*
* <li>ai_protocol:
* indicates which transport protocol is wanted: IPPROTO_UDP or
* IPPROTO_TCP. If ai_protocol is zero the caller will accept any
* protocol.</li>
*
* <li>ai_flags:
* Flag bits. If the AI_CANONNAME bit is set, a successful call to
* getaddrinfo() will return a null-terminated string
* containing the canonical name of the specified hostname in
* ai_canonname of the first addrinfo structure returned. Setting
* the AI_PASSIVE bit indicates that the returned socket address
* structure is intended for used in a call to bind(2). In this
* case, if the hostname argument is a NULL pointer, then the IP
* address portion of the socket address structure will be set to
* INADDR_ANY for an IPv4 address or IN6ADDR_ANY_INIT for an IPv6
* address.<br /><br />
*
* When ai_flags does not set the AI_PASSIVE bit, the returned
* socket address structure will be ready for use in a call to
* connect(2) for a connection-oriented protocol or connect(2),
* sendto(2), or sendmsg(2) if a connectionless protocol was
* chosen. The IP address portion of the socket address structure
* will be set to the loopback address if hostname is a NULL
* pointer and AI_PASSIVE is not set in ai_flags.<br /><br />
*
* If ai_flags is set to AI_NUMERICHOST it indicates that hostname
* should be treated as a numeric string defining an IPv4 or IPv6
* address and no name resolution should be attempted.
* </li></ul>
*
* All other elements of the struct addrinfo passed via hints must be
* zero.
*
* A hints of NULL is treated as if the caller provided a struct addrinfo
* initialized to zero with ai_familyset to PF_UNSPEC.
*
* After a successful call to getaddrinfo(), *res is a pointer to a
* linked list of one or more addrinfo structures. Each struct addrinfo
* in this list cn be processed by following the ai_next pointer, until a
* NULL pointer is encountered. The three members ai_family, ai_socktype,
* and ai_protocol in each returned addrinfo structure contain the
* corresponding arguments for a call to socket(2). For each addrinfo
* structure in the list, the ai_addr member points to a filled-in socket
* address structure of length ai_addrlen.
*
* All of the information returned by getaddrinfo() is dynamically
* allocated: the addrinfo structures, and the socket address structures
* and canonical host name strings pointed to by the addrinfostructures.
* Memory allocated for the dynamically allocated structures created by a
* successful call to getaddrinfo() is released by freeaddrinfo().
* ai is a pointer to a struct addrinfo created by a call to getaddrinfo().
*
* \section irsreturn RETURN VALUES
*
* getaddrinfo() returns zero on success or one of the error codes
* listed in gai_strerror() if an error occurs. If both hostname and
* servname are NULL getaddrinfo() returns #EAI_NONAME.
*
* \section irssee SEE ALSO
*
* getaddrinfo(), freeaddrinfo(),
* gai_strerror(), RFC3493, getservbyname(3), connect(2),
* sendto(2), sendmsg(2), socket(2).
*/
#include <config.h>
#include <inttypes.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#ifdef _WIN32
#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
#endif
#include <isc/app.h>
#include <isc/buffer.h>
#include <isc/lib.h>
#include <isc/mem.h>
#include <isc/print.h>
#include <isc/sockaddr.h>
#include <isc/string.h>
#include <isc/util.h>
#include <isc/mutex.h>
#include <dns/client.h>
#include <dns/fixedname.h>
#include <dns/name.h>
#include <dns/rdata.h>
#include <dns/rdataset.h>
#include <dns/rdatastruct.h>
#include <dns/rdatatype.h>
#include <dns/result.h>
#include <irs/context.h>
#include <irs/netdb.h>
#include <irs/resconf.h>
#define SA(addr) ((struct sockaddr *)(addr))
#define SIN(addr) ((struct sockaddr_in *)(addr))
#define SIN6(addr) ((struct sockaddr_in6 *)(addr))
#define SLOCAL(addr) ((struct sockaddr_un *)(addr))
/*! \struct addrinfo
*/
static struct addrinfo
*ai_concat(struct addrinfo *ai1, struct addrinfo *ai2),
*ai_reverse(struct addrinfo *oai),
*ai_clone(struct addrinfo *oai, int family),
*ai_alloc(int family, int addrlen);
#ifdef AF_LOCAL
static int get_local(const char *name, int socktype, struct addrinfo **res);
#endif
static int
resolve_name(int family, const char *hostname, int flags,
struct addrinfo **aip, int socktype, int port);
static int add_ipv4(const char *hostname, int flags, struct addrinfo **aip,
int socktype, int port);
static int add_ipv6(const char *hostname, int flags, struct addrinfo **aip,
int socktype, int port);
static void set_order(int, int (**)(const char *, int, struct addrinfo **,
int, int));
static void _freeaddrinfo(struct addrinfo *ai);
#define FOUND_IPV4 0x1
#define FOUND_IPV6 0x2
#define FOUND_MAX 2
/*%
* Try converting the scope identifier in 'src' to a network interface index.
* Upon success, return true and store the resulting index in 'dst'. Upon
* failure, return false.
*/
static bool
parse_scopeid(const char *src, uint32_t *dst) {
uint32_t scopeid = 0;
REQUIRE(src != NULL);
REQUIRE(dst != NULL);
#ifdef HAVE_IF_NAMETOINDEX
/*
* Try using if_nametoindex() first if it is available. As it does not
* handle numeric scopes, we do not simply return if it fails.
*/
scopeid = (uint32_t)if_nametoindex(src);
#endif
/*
* Fall back to numeric scope processing if if_nametoindex() either
* fails or is unavailable.
*/
if (scopeid == 0) {
char *endptr = NULL;
scopeid = (uint32_t)strtoul(src, &endptr, 10);
/*
* The scope identifier must not be empty and no trailing
* characters are allowed after it.
*/
if (src == endptr || endptr == NULL || *endptr != '\0') {
return (false);
}
}
*dst = scopeid;
return (true);
}
#define ISC_AI_MASK (AI_PASSIVE|AI_CANONNAME|AI_NUMERICHOST)
/*%
* Get a list of IP addresses and port numbers for host hostname and
* service servname.
*/
int
getaddrinfo(const char *hostname, const char *servname,
const struct addrinfo *hints, struct addrinfo **res)
{
struct servent *sp;
const char *proto;
int family, socktype, flags, protocol;
struct addrinfo *ai, *ai_list;
int err = 0;
int port, i;
int (*net_order[FOUND_MAX+1])(const char *, int, struct addrinfo **,
int, int);
if (hostname == NULL && servname == NULL)
return (EAI_NONAME);
proto = NULL;
if (hints != NULL) {
if ((hints->ai_flags & ~(ISC_AI_MASK)) != 0)
return (EAI_BADFLAGS);
if (hints->ai_addrlen || hints->ai_canonname ||
hints->ai_addr || hints->ai_next) {
errno = EINVAL;
return (EAI_SYSTEM);
}
family = hints->ai_family;
socktype = hints->ai_socktype;
protocol = hints->ai_protocol;
flags = hints->ai_flags;
switch (family) {
case AF_UNSPEC:
switch (hints->ai_socktype) {
case SOCK_STREAM:
proto = "tcp";
break;
case SOCK_DGRAM:
proto = "udp";
break;
}
break;
case AF_INET:
case AF_INET6:
switch (hints->ai_socktype) {
case 0:
break;
case SOCK_STREAM:
proto = "tcp";
break;
case SOCK_DGRAM:
proto = "udp";
break;
case SOCK_RAW:
break;
default:
return (EAI_SOCKTYPE);
}
break;
#ifdef AF_LOCAL
case AF_LOCAL:
switch (hints->ai_socktype) {
case 0:
break;
case SOCK_STREAM:
break;
case SOCK_DGRAM:
break;
default:
return (EAI_SOCKTYPE);
}
break;
#endif
default:
return (EAI_FAMILY);
}
} else {
protocol = 0;
family = 0;
socktype = 0;
flags = 0;
}
#ifdef AF_LOCAL
/*!
* First, deal with AF_LOCAL. If the family was not set,
* then assume AF_LOCAL if the first character of the
* hostname/servname is '/'.
*/
if (hostname != NULL &&
(family == AF_LOCAL || (family == 0 && *hostname == '/')))
return (get_local(hostname, socktype, res));
if (servname != NULL &&
(family == AF_LOCAL || (family == 0 && *servname == '/')))
return (get_local(servname, socktype, res));
#endif
/*
* Ok, only AF_INET and AF_INET6 left.
*/
ai_list = NULL;
/*
* First, look up the service name (port) if it was
* requested. If the socket type wasn't specified, then
* try and figure it out.
*/
if (servname != NULL) {
char *e;
port = strtol(servname, &e, 10);
if (*e == '\0') {
if (socktype == 0) {
return (EAI_SOCKTYPE);
}
if (port < 0 || port > 65535) {
return (EAI_SERVICE);
}
port = htons((unsigned short) port);
} else {
#ifdef _WIN32
WORD wVersionRequested;
WSADATA wsaData;
wVersionRequested = MAKEWORD(2, 0);
err = WSAStartup(wVersionRequested, &wsaData );
if (err != 0) {
return (EAI_FAIL);
}
#endif
sp = getservbyname(servname, proto);
if (sp != NULL)
port = sp->s_port;
#ifdef _WIN32
WSACleanup();
#endif
if (sp == NULL) {
return (EAI_SERVICE);
}
if (socktype == 0) {
if (strcmp(sp->s_proto, "tcp") == 0) {
socktype = SOCK_STREAM;
} else if (strcmp(sp->s_proto, "udp") == 0) {
socktype = SOCK_DGRAM;
}
}
}
} else {
port = 0;
}
/*
* Next, deal with just a service name, and no hostname.
* (we verified that one of them was non-null up above).
*/
if (hostname == NULL && (flags & AI_PASSIVE) != 0) {
if (family == AF_INET || family == 0) {
ai = ai_alloc(AF_INET, sizeof(struct sockaddr_in));
if (ai == NULL)
return (EAI_MEMORY);
ai->ai_socktype = socktype;
ai->ai_protocol = protocol;
SIN(ai->ai_addr)->sin_port = port;
ai->ai_next = ai_list;
ai_list = ai;
}
if (family == AF_INET6 || family == 0) {
ai = ai_alloc(AF_INET6, sizeof(struct sockaddr_in6));
if (ai == NULL) {
_freeaddrinfo(ai_list);
return (EAI_MEMORY);
}
ai->ai_socktype = socktype;
ai->ai_protocol = protocol;
SIN6(ai->ai_addr)->sin6_port = port;
ai->ai_next = ai_list;
ai_list = ai;
}
*res = ai_list;
return (0);
}
/*
* If the family isn't specified or AI_NUMERICHOST specified, check
* first to see if it is a numeric address.
* Though the gethostbyname2() routine will recognize numeric addresses,
* it will only recognize the format that it is being called for. Thus,
* a numeric AF_INET address will be treated by the AF_INET6 call as
* a domain name, and vice versa. Checking for both numerics here
* avoids that.
*/
if (hostname != NULL &&
(family == 0 || (flags & AI_NUMERICHOST) != 0)) {
char abuf[sizeof(struct in6_addr)];
char nbuf[NI_MAXHOST];
int addrsize, addroff;
char ntmp[NI_MAXHOST];
uint32_t scopeid = 0;
/*
* Scope identifier portion.
*/
ntmp[0] = '\0';
if (strchr(hostname, '%') != NULL) {
char *p;
strlcpy(ntmp, hostname, sizeof(ntmp));
p = strchr(ntmp, '%');
if (p != NULL && parse_scopeid(p + 1, &scopeid)) {
*p = '\0';
} else {
ntmp[0] = '\0';
}
}
if (inet_pton(AF_INET, hostname, (struct in_addr *)abuf)
== 1) {
if (family == AF_INET6) {
/*
* Convert to a V4 mapped address.
*/
struct in6_addr *a6 = (struct in6_addr *)abuf;
memmove(&a6->s6_addr[12], &a6->s6_addr[0], 4);
memset(&a6->s6_addr[10], 0xff, 2);
memset(&a6->s6_addr[0], 0, 10);
goto inet6_addr;
}
addrsize = sizeof(struct in_addr);
addroff = offsetof(struct sockaddr_in, sin_addr);
family = AF_INET;
goto common;
} else if (ntmp[0] != '\0' &&
inet_pton(AF_INET6, ntmp, abuf) == 1) {
if (family && family != AF_INET6)
return (EAI_NONAME);
addrsize = sizeof(struct in6_addr);
addroff = offsetof(struct sockaddr_in6, sin6_addr);
family = AF_INET6;
goto common;
} else if (inet_pton(AF_INET6, hostname, abuf) == 1) {
if (family != 0 && family != AF_INET6)
return (EAI_NONAME);
inet6_addr:
addrsize = sizeof(struct in6_addr);
addroff = offsetof(struct sockaddr_in6, sin6_addr);
family = AF_INET6;
common:
ai = ai_alloc(family,
((family == AF_INET6) ?
sizeof(struct sockaddr_in6) :
sizeof(struct sockaddr_in)));
if (ai == NULL)
return (EAI_MEMORY);
ai_list = ai;
ai->ai_socktype = socktype;
SIN(ai->ai_addr)->sin_port = port;
memmove((char *)ai->ai_addr + addroff, abuf, addrsize);
if (ai->ai_family == AF_INET6) {
SIN6(ai->ai_addr)->sin6_scope_id = scopeid;
}
if ((flags & AI_CANONNAME) != 0) {
if (getnameinfo(ai->ai_addr,
(socklen_t)ai->ai_addrlen,
nbuf, sizeof(nbuf), NULL, 0,
NI_NUMERICHOST) == 0) {
ai->ai_canonname = strdup(nbuf);
if (ai->ai_canonname == NULL) {
_freeaddrinfo(ai);
return (EAI_MEMORY);
}
} else {
/* XXX raise error? */
ai->ai_canonname = NULL;
}
}
goto done;
} else if ((flags & AI_NUMERICHOST) != 0) {
return (EAI_NONAME);
}
}
if (hostname == NULL && (flags & AI_PASSIVE) == 0) {
set_order(family, net_order);
for (i = 0; i < FOUND_MAX; i++) {
if (net_order[i] == NULL)
break;
err = (net_order[i])(hostname, flags, &ai_list,
socktype, port);
if (err != 0) {
if (ai_list != NULL) {
_freeaddrinfo(ai_list);
ai_list = NULL;
}
break;
}
}
} else
err = resolve_name(family, hostname, flags, &ai_list,
socktype, port);
if (ai_list == NULL) {
if (err == 0)
err = EAI_NONAME;
return (err);
}
done:
ai_list = ai_reverse(ai_list);
*res = ai_list;
return (0);
}
typedef struct gai_restrans {
dns_clientrestrans_t *xid;
bool is_inprogress;
int error;
struct addrinfo ai_sentinel;
struct gai_resstate *resstate;
} gai_restrans_t;
typedef struct gai_resstate {
isc_mem_t *mctx;
struct gai_statehead *head;
dns_fixedname_t fixedname;
dns_name_t *qname;
gai_restrans_t *trans4;
gai_restrans_t *trans6;
ISC_LINK(struct gai_resstate) link;
} gai_resstate_t;
typedef struct gai_statehead {
int ai_family;
int ai_flags;
int ai_socktype;
int ai_port;
isc_appctx_t *actx;
dns_client_t *dnsclient;
isc_mutex_t list_lock;
ISC_LIST(struct gai_resstate) resstates;
unsigned int activestates;
} gai_statehead_t;
static isc_result_t
make_resstate(isc_mem_t *mctx, gai_statehead_t *head, const char *hostname,
const char *domain, gai_resstate_t **statep)
{
isc_result_t result;
gai_resstate_t *state;
dns_fixedname_t fixeddomain;
dns_name_t *qdomain;
unsigned int namelen;
isc_buffer_t b;
bool need_v4 = false;
bool need_v6 = false;
state = isc_mem_get(mctx, sizeof(*state));
if (state == NULL)
return (ISC_R_NOMEMORY);
/* Construct base domain name */
namelen = strlen(domain);
isc_buffer_constinit(&b, domain, namelen);
isc_buffer_add(&b, namelen);
qdomain = dns_fixedname_initname(&fixeddomain);
result = dns_name_fromtext(qdomain, &b, dns_rootname, 0, NULL);
if (result != ISC_R_SUCCESS) {
isc_mem_put(mctx, state, sizeof(*state));
return (result);
}
/* Construct query name */
namelen = strlen(hostname);
isc_buffer_constinit(&b, hostname, namelen);
isc_buffer_add(&b, namelen);
state->qname = dns_fixedname_initname(&state->fixedname);
result = dns_name_fromtext(state->qname, &b, qdomain, 0, NULL);
if (result != ISC_R_SUCCESS) {
isc_mem_put(mctx, state, sizeof(*state));
return (result);
}
if (head->ai_family == AF_UNSPEC || head->ai_family == AF_INET)
need_v4 = true;
if (head->ai_family == AF_UNSPEC || head->ai_family == AF_INET6)
need_v6 = true;
state->trans6 = NULL;
state->trans4 = NULL;
if (need_v4) {
state->trans4 = isc_mem_get(mctx, sizeof(gai_restrans_t));
if (state->trans4 == NULL) {
isc_mem_put(mctx, state, sizeof(*state));
return (ISC_R_NOMEMORY);
}
state->trans4->error = 0;
state->trans4->xid = NULL;
state->trans4->resstate = state;
state->trans4->is_inprogress = true;
state->trans4->ai_sentinel.ai_next = NULL;
}
if (need_v6) {
state->trans6 = isc_mem_get(mctx, sizeof(gai_restrans_t));
if (state->trans6 == NULL) {
if (state->trans4 != NULL)
isc_mem_put(mctx, state->trans4,
sizeof(*state->trans4));
isc_mem_put(mctx, state, sizeof(*state));
return (ISC_R_NOMEMORY);
}
state->trans6->error = 0;
state->trans6->xid = NULL;
state->trans6->resstate = state;
state->trans6->is_inprogress = true;
state->trans6->ai_sentinel.ai_next = NULL;
}
state->mctx = mctx;
state->head = head;
ISC_LINK_INIT(state, link);
*statep = state;
return (ISC_R_SUCCESS);
}
static isc_result_t
make_resstates(isc_mem_t *mctx, const char *hostname, gai_statehead_t *head,
irs_resconf_t *resconf)
{
isc_result_t result;
irs_resconf_searchlist_t *searchlist;
irs_resconf_search_t *searchent;
gai_resstate_t *resstate, *resstate0;
resstate0 = NULL;
result = make_resstate(mctx, head, hostname, ".", &resstate0);
if (result != ISC_R_SUCCESS)
return (result);
searchlist = irs_resconf_getsearchlist(resconf);
for (searchent = ISC_LIST_HEAD(*searchlist); searchent != NULL;
searchent = ISC_LIST_NEXT(searchent, link)) {
resstate = NULL;
result = make_resstate(mctx, head, hostname,
(const char *)searchent->domain,
&resstate);
if (result != ISC_R_SUCCESS)
break;
ISC_LIST_APPEND(head->resstates, resstate, link);
head->activestates++;
}
/*
* Insert the original hostname either at the head or the tail of the
* state list, depending on the number of labels contained in the
* original name and the 'ndots' configuration parameter.
*/
if (dns_name_countlabels(resstate0->qname) >
irs_resconf_getndots(resconf) + 1) {
ISC_LIST_PREPEND(head->resstates, resstate0, link);
} else
ISC_LIST_APPEND(head->resstates, resstate0, link);
head->activestates++;
if (result != ISC_R_SUCCESS) {
while ((resstate = ISC_LIST_HEAD(head->resstates)) != NULL) {
ISC_LIST_UNLINK(head->resstates, resstate, link);
if (resstate->trans4 != NULL) {
isc_mem_put(mctx, resstate->trans4,
sizeof(*resstate->trans4));
}
if (resstate->trans6 != NULL) {
isc_mem_put(mctx, resstate->trans6,
sizeof(*resstate->trans6));
}
isc_mem_put(mctx, resstate, sizeof(*resstate));
}
}
return (result);
}
static void
process_answer(isc_task_t *task, isc_event_t *event) {
int error = 0, family;
gai_restrans_t *trans = event->ev_arg;
gai_resstate_t *resstate;
dns_clientresevent_t *rev = (dns_clientresevent_t *)event;
dns_rdatatype_t qtype;
dns_name_t *name;
bool wantcname;
REQUIRE(trans != NULL);
resstate = trans->resstate;
REQUIRE(resstate != NULL);
REQUIRE(task != NULL);
if (trans == resstate->trans4) {
family = AF_INET;
qtype = dns_rdatatype_a;
} else {
INSIST(trans == resstate->trans6);
family = AF_INET6;
qtype = dns_rdatatype_aaaa;
}
INSIST(trans->is_inprogress);
trans->is_inprogress = false;
switch (rev->result) {
case ISC_R_SUCCESS:
case DNS_R_NCACHENXDOMAIN: /* treat this as a fatal error? */
case DNS_R_NCACHENXRRSET:
break;
default:
switch (rev->vresult) {
case DNS_R_SIGINVALID:
case DNS_R_SIGEXPIRED:
case DNS_R_SIGFUTURE:
case DNS_R_KEYUNAUTHORIZED:
case DNS_R_MUSTBESECURE:
case DNS_R_COVERINGNSEC:
case DNS_R_NOTAUTHORITATIVE:
case DNS_R_NOVALIDKEY:
case DNS_R_NOVALIDDS:
case DNS_R_NOVALIDSIG:
error = EAI_INSECUREDATA;
break;
default:
error = EAI_FAIL;
}
goto done;
}
wantcname = ((resstate->head->ai_flags & AI_CANONNAME) != 0);
/* Parse the response and construct the addrinfo chain */
for (name = ISC_LIST_HEAD(rev->answerlist); name != NULL;
name = ISC_LIST_NEXT(name, link)) {
isc_result_t result;
dns_rdataset_t *rdataset;
char cname[1024];
if (wantcname) {
isc_buffer_t b;
isc_buffer_init(&b, cname, sizeof(cname));
result = dns_name_totext(name, true, &b);
if (result != ISC_R_SUCCESS) {
error = EAI_FAIL;
goto done;
}
isc_buffer_putuint8(&b, '\0');
}
for (rdataset = ISC_LIST_HEAD(name->list);
rdataset != NULL;
rdataset = ISC_LIST_NEXT(rdataset, link)) {
if (!dns_rdataset_isassociated(rdataset))
continue;
if (rdataset->type != qtype)
continue;
for (result = dns_rdataset_first(rdataset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(rdataset)) {
struct addrinfo *ai;
dns_rdata_t rdata;
dns_rdata_in_a_t rdata_a;
dns_rdata_in_aaaa_t rdata_aaaa;
ai = ai_alloc(family,
((family == AF_INET6) ?
sizeof(struct sockaddr_in6) :
sizeof(struct sockaddr_in)));
if (ai == NULL) {
error = EAI_MEMORY;
goto done;
}
ai->ai_socktype = resstate->head->ai_socktype;
ai->ai_next = trans->ai_sentinel.ai_next;
trans->ai_sentinel.ai_next = ai;
/*
* Set AF-specific parameters
* (IPv4/v6 address/port)
*/
dns_rdata_init(&rdata);
switch (family) {
case AF_INET:
dns_rdataset_current(rdataset, &rdata);
result = dns_rdata_tostruct(&rdata,
&rdata_a,
NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
SIN(ai->ai_addr)->sin_port =
resstate->head->ai_port;
memmove(&SIN(ai->ai_addr)->sin_addr,
&rdata_a.in_addr, 4);
dns_rdata_freestruct(&rdata_a);
break;
case AF_INET6:
dns_rdataset_current(rdataset, &rdata);
result = dns_rdata_tostruct(&rdata,
&rdata_aaaa,
NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
SIN6(ai->ai_addr)->sin6_port =
resstate->head->ai_port;
memmove(&SIN6(ai->ai_addr)->sin6_addr,
&rdata_aaaa.in6_addr, 16);
dns_rdata_freestruct(&rdata_aaaa);
break;
}
if (wantcname) {
ai->ai_canonname = strdup(cname);
if (ai->ai_canonname == NULL) {
error = EAI_MEMORY;
goto done;
}
}
}
}
}
done:
dns_client_freeresanswer(resstate->head->dnsclient, &rev->answerlist);
dns_client_destroyrestrans(&trans->xid);
isc_event_free(&event);
/* Make sure that error == 0 iff we have a non-empty list */
if (error == 0) {
if (trans->ai_sentinel.ai_next == NULL)
error = EAI_NONAME;
} else {
if (trans->ai_sentinel.ai_next != NULL) {
_freeaddrinfo(trans->ai_sentinel.ai_next);
trans->ai_sentinel.ai_next = NULL;
}
}
trans->error = error;
/* Check whether we are done */
if ((resstate->trans4 == NULL || !resstate->trans4->is_inprogress) &&
(resstate->trans6 == NULL || !resstate->trans6->is_inprogress)) {
/*
* We're done for this state. If there is no other outstanding
* state, we can exit.
*/
resstate->head->activestates--;
if (resstate->head->activestates == 0) {
isc_app_ctxsuspend(resstate->head->actx);
return;
}
/*
* There are outstanding states, but if we are at the head
* of the state list (i.e., at the highest search priority)
* and have any answer, we can stop now by canceling the
* others.
*/
LOCK(&resstate->head->list_lock);
if (resstate == ISC_LIST_HEAD(resstate->head->resstates)) {
if ((resstate->trans4 != NULL &&
resstate->trans4->ai_sentinel.ai_next != NULL) ||
(resstate->trans6 != NULL &&
resstate->trans6->ai_sentinel.ai_next != NULL)) {
gai_resstate_t *rest;
for (rest = ISC_LIST_NEXT(resstate, link);
rest != NULL;
rest = ISC_LIST_NEXT(rest, link)) {
if (rest->trans4 != NULL &&
rest->trans4->xid != NULL)
dns_client_cancelresolve(
rest->trans4->xid);
if (rest->trans6 != NULL &&
rest->trans6->xid != NULL)
dns_client_cancelresolve(
rest->trans6->xid);
}
} else {
/*
* This search fails, so we move to the tail
* of the list so that the next entry will
* have the highest priority.
*/
ISC_LIST_UNLINK(resstate->head->resstates,
resstate, link);
ISC_LIST_APPEND(resstate->head->resstates,
resstate, link);
}
}
UNLOCK(&resstate->head->list_lock);
}
}
static int
resolve_name(int family, const char *hostname, int flags,
struct addrinfo **aip, int socktype, int port)
{
isc_result_t result;
irs_context_t *irsctx;
irs_resconf_t *conf;
isc_mem_t *mctx;
isc_appctx_t *actx;
isc_task_t *task;
int terror = 0;
int error = 0;
dns_client_t *client;
gai_resstate_t *resstate;
gai_statehead_t head;
bool all_fail = true;
/* get IRS context and the associated parameters */
irsctx = NULL;
result = irs_context_get(&irsctx);
if (result != ISC_R_SUCCESS)
return (EAI_FAIL);
actx = irs_context_getappctx(irsctx);
mctx = irs_context_getmctx(irsctx);
task = irs_context_gettask(irsctx);
conf = irs_context_getresconf(irsctx);
client = irs_context_getdnsclient(irsctx);
/* construct resolution states */
head.activestates = 0;
head.ai_family = family;
head.ai_socktype = socktype;
head.ai_flags = flags;
head.ai_port = port;
head.actx = actx;
head.dnsclient = client;
isc_mutex_init(&head.list_lock);
ISC_LIST_INIT(head.resstates);
result = make_resstates(mctx, hostname, &head, conf);
if (result != ISC_R_SUCCESS) {
isc_mutex_destroy(&head.list_lock);
return (EAI_FAIL);
}
LOCK(&head.list_lock);
for (resstate = ISC_LIST_HEAD(head.resstates);
resstate != NULL; resstate = ISC_LIST_NEXT(resstate, link)) {
if (resstate->trans4 != NULL) {
result = dns_client_startresolve(client,
resstate->qname,
dns_rdataclass_in,
dns_rdatatype_a,
0, task,
process_answer,
resstate->trans4,
&resstate->trans4->xid);
if (result == ISC_R_SUCCESS) {
resstate->trans4->is_inprogress = true;
all_fail = false;
} else
resstate->trans4->is_inprogress = false;
}
if (resstate->trans6 != NULL) {
result = dns_client_startresolve(client,
resstate->qname,
dns_rdataclass_in,
dns_rdatatype_aaaa,
0, task,
process_answer,
resstate->trans6,
&resstate->trans6->xid);
if (result == ISC_R_SUCCESS) {
resstate->trans6->is_inprogress = true;
all_fail = false;
} else
resstate->trans6->is_inprogress= false;
}
}
UNLOCK(&head.list_lock);
if (!all_fail) {
/* Start all the events */
isc_app_ctxrun(actx);
} else
error = EAI_FAIL;
/* Cleanup */
while ((resstate = ISC_LIST_HEAD(head.resstates)) != NULL) {
int terror4 = 0, terror6 = 0;
ISC_LIST_UNLINK(head.resstates, resstate, link);
if (*aip == NULL) {
struct addrinfo *sentinel4 = NULL;
struct addrinfo *sentinel6 = NULL;
if (resstate->trans4 != NULL) {
sentinel4 =
resstate->trans4->ai_sentinel.ai_next;
resstate->trans4->ai_sentinel.ai_next = NULL;
}
if (resstate->trans6 != NULL) {
sentinel6 =
resstate->trans6->ai_sentinel.ai_next;
resstate->trans6->ai_sentinel.ai_next = NULL;
}
*aip = ai_concat(sentinel4, sentinel6);
}
if (resstate->trans4 != NULL) {
INSIST(resstate->trans4->xid == NULL);
terror4 = resstate->trans4->error;
isc_mem_put(mctx, resstate->trans4,
sizeof(*resstate->trans4));
}
if (resstate->trans6 != NULL) {
INSIST(resstate->trans6->xid == NULL);
terror6 = resstate->trans6->error;
isc_mem_put(mctx, resstate->trans6,
sizeof(*resstate->trans6));
}
/*
* If the entire lookup fails, we need to choose an appropriate
* error code from individual codes. We'll try to provide as
* specific a code as possible. In general, we are going to
* find an error code other than EAI_NONAME (which is too
* generic and may actually not be problematic in some cases).
* EAI_NONAME will be set below if no better code is found.
*/
if (terror == 0 || terror == EAI_NONAME) {
if (terror4 != 0 && terror4 != EAI_NONAME)
terror = terror4;
else if (terror6 != 0 && terror6 != EAI_NONAME)
terror = terror6;
}
isc_mem_put(mctx, resstate, sizeof(*resstate));
}
if (*aip == NULL) {
error = terror;
if (error == 0)
error = EAI_NONAME;
}
#if 1 /* XXX: enabled for finding leaks. should be cleaned up later. */
isc_app_ctxfinish(actx);
irs_context_destroy(&irsctx);
#endif
isc_mutex_destroy(&head.list_lock);
return (error);
}
static void
set_order(int family, int (**net_order)(const char *, int, struct addrinfo **,
int, int))
{
char *order, *tok, *last;
int found;
if (family) {
switch (family) {
case AF_INET:
*net_order++ = add_ipv4;
break;
case AF_INET6:
*net_order++ = add_ipv6;
break;
}
} else {
order = getenv("NET_ORDER");
found = 0;
if (order != NULL) {
last = NULL;
for (tok = strtok_r(order, ":", &last);
tok;
tok = strtok_r(NULL, ":", &last))
{
if (strcasecmp(tok, "inet6") == 0) {
if ((found & FOUND_IPV6) == 0) {
*net_order++ = add_ipv6;
}
found |= FOUND_IPV6;
} else if (strcasecmp(tok, "inet") == 0 ||
strcasecmp(tok, "inet4") == 0) {
if ((found & FOUND_IPV4) == 0) {
*net_order++ = add_ipv4;
}
found |= FOUND_IPV4;
}
}
}
/*
* Add in anything that we didn't find.
*/
if ((found & FOUND_IPV4) == 0)
*net_order++ = add_ipv4;
if ((found & FOUND_IPV6) == 0)
*net_order++ = add_ipv6;
}
*net_order = NULL;
return;
}
static char v4_loop[4] = { 127, 0, 0, 1 };
static int
add_ipv4(const char *hostname, int flags, struct addrinfo **aip,
int socktype, int port)
{
struct addrinfo *ai;
UNUSED(hostname);
UNUSED(flags);
ai = ai_clone(*aip, AF_INET); /* don't use ai_clone() */
if (ai == NULL)
return (EAI_MEMORY);
*aip = ai;
ai->ai_socktype = socktype;
SIN(ai->ai_addr)->sin_port = port;
memmove(&SIN(ai->ai_addr)->sin_addr, v4_loop, 4);
return (0);
}
static char v6_loop[16] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 };
static int
add_ipv6(const char *hostname, int flags, struct addrinfo **aip,
int socktype, int port)
{
struct addrinfo *ai;
UNUSED(hostname);
UNUSED(flags);
ai = ai_clone(*aip, AF_INET6); /* don't use ai_clone() */
if (ai == NULL)
return (EAI_MEMORY);
*aip = ai;
ai->ai_socktype = socktype;
SIN6(ai->ai_addr)->sin6_port = port;
memmove(&SIN6(ai->ai_addr)->sin6_addr, v6_loop, 16);
return (0);
}
/*% Free address info. */
void
freeaddrinfo(struct addrinfo *ai) {
_freeaddrinfo(ai);
}
static void
_freeaddrinfo(struct addrinfo *ai) {
struct addrinfo *ai_next;
while (ai != NULL) {
ai_next = ai->ai_next;
if (ai->ai_addr != NULL)
free(ai->ai_addr);
if (ai->ai_canonname)
free(ai->ai_canonname);
free(ai);
ai = ai_next;
}
}
#ifdef AF_LOCAL
static int
get_local(const char *name, int socktype, struct addrinfo **res) {
struct addrinfo *ai;
struct sockaddr_un *slocal;
if (socktype == 0)
return (EAI_SOCKTYPE);
ai = ai_alloc(AF_LOCAL, sizeof(*slocal));
if (ai == NULL)
return (EAI_MEMORY);
slocal = SLOCAL(ai->ai_addr);
strlcpy(slocal->sun_path, name, sizeof(slocal->sun_path));
ai->ai_socktype = socktype;
/*
* ai->ai_flags, ai->ai_protocol, ai->ai_canonname,
* and ai->ai_next were initialized to zero.
*/
*res = ai;
return (0);
}
#endif
/*!
* Allocate an addrinfo structure, and a sockaddr structure
* of the specificed length. We initialize:
* ai_addrlen
* ai_family
* ai_addr
* ai_addr->sa_family
* ai_addr->sa_len (IRS_PLATFORM_HAVESALEN)
* and everything else is initialized to zero.
*/
static struct addrinfo *
ai_alloc(int family, int addrlen) {
struct addrinfo *ai;
ai = (struct addrinfo *)calloc(1, sizeof(*ai));
if (ai == NULL)
return (NULL);
ai->ai_addr = SA(calloc(1, addrlen));
if (ai->ai_addr == NULL) {
free(ai);
return (NULL);
}
ai->ai_addrlen = addrlen;
ai->ai_family = family;
ai->ai_addr->sa_family = family;
#ifdef IRS_PLATFORM_HAVESALEN
ai->ai_addr->sa_len = addrlen;
#endif
return (ai);
}
static struct addrinfo *
ai_clone(struct addrinfo *oai, int family) {
struct addrinfo *ai;
ai = ai_alloc(family, ((family == AF_INET6) ?
sizeof(struct sockaddr_in6) : sizeof(struct sockaddr_in)));
if (ai == NULL)
return (NULL);
if (oai == NULL)
return (ai);
ai->ai_flags = oai->ai_flags;
ai->ai_socktype = oai->ai_socktype;
ai->ai_protocol = oai->ai_protocol;
ai->ai_canonname = NULL;
ai->ai_next = oai;
return (ai);
}
static struct addrinfo *
ai_reverse(struct addrinfo *oai) {
struct addrinfo *nai, *tai;
nai = NULL;
while (oai != NULL) {
/*
* Grab one off the old list.
*/
tai = oai;
oai = oai->ai_next;
/*
* Put it on the front of the new list.
*/
tai->ai_next = nai;
nai = tai;
}
return (nai);
}
static struct addrinfo *
ai_concat(struct addrinfo *ai1, struct addrinfo *ai2) {
struct addrinfo *ai_tmp;
if (ai1 == NULL)
return (ai2);
else if (ai2 == NULL)
return (ai1);
for (ai_tmp = ai1; ai_tmp != NULL && ai_tmp->ai_next != NULL;
ai_tmp = ai_tmp->ai_next)
;
ai_tmp->ai_next = ai2;
return (ai1);
}