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-rw-r--r--lib/irs/getnameinfo.c409
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diff --git a/lib/irs/getnameinfo.c b/lib/irs/getnameinfo.c
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+/*
+ * 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 */
+
+/*
+ * 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.
+ */
+
+/**
+ * getnameinfo() returns the hostname for the struct sockaddr sa which is
+ * salen bytes long. The hostname is of length hostlen and is returned via
+ * *host. The maximum length of the hostname is 1025 bytes: #NI_MAXHOST.
+ *
+ * The name of the service associated with the port number in sa is
+ * returned in *serv. It is servlen bytes long. The maximum length of the
+ * service name is #NI_MAXSERV - 32 bytes.
+ *
+ * The flags argument sets the following bits:
+ *
+ * \li #NI_NOFQDN:
+ * A fully qualified domain name is not required for local hosts.
+ * The local part of the fully qualified domain name is returned
+ * instead.
+ *
+ * \li #NI_NUMERICHOST
+ * Return the address in numeric form, as if calling inet_ntop(),
+ * instead of a host name.
+ *
+ * \li #NI_NAMEREQD
+ * A name is required. If the hostname cannot be found in the DNS
+ * and this flag is set, a non-zero error code is returned. If the
+ * hostname is not found and the flag is not set, the address is
+ * returned in numeric form.
+ *
+ * \li #NI_NUMERICSERV
+ * The service name is returned as a digit string representing the
+ * port number.
+ *
+ * \li #NI_DGRAM
+ * Specifies that the service being looked up is a datagram
+ * service, and causes getservbyport() to be called with a second
+ * argument of "udp" instead of its default of "tcp". This is
+ * required for the few ports (512-514) that have different
+ * services for UDP and TCP.
+ *
+ * \section getnameinfo_return Return Values
+ *
+ * getnameinfo() returns 0 on success or a non-zero error code if
+ * an error occurs.
+ *
+ * \section getname_see See Also
+ *
+ * RFC3493, getservbyport(),
+ * getnamebyaddr(). inet_ntop().
+ */
+
+#include <config.h>
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <isc/netaddr.h>
+#include <isc/print.h>
+#include <isc/sockaddr.h>
+#include <isc/string.h>
+#include <isc/util.h>
+
+#include <dns/byaddr.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/result.h>
+
+#include <irs/context.h>
+#include <irs/netdb.h>
+
+#define SUCCESS 0
+
+/*% afd structure definition */
+static struct afd {
+ int a_af;
+ size_t a_addrlen;
+ size_t a_socklen;
+} afdl [] = {
+ /*!
+ * First entry is linked last...
+ */
+ { AF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in) },
+ { AF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6) },
+ {0, 0, 0},
+};
+
+/*!
+ * The test against 0 is there to keep the Solaris compiler
+ * from complaining about "end-of-loop code not reached".
+ */
+#define ERR(code) \
+ do { result = (code); \
+ if (result != 0) goto cleanup; \
+ } while (0)
+
+int
+getnameinfo(const struct sockaddr *sa, IRS_GETNAMEINFO_SOCKLEN_T salen,
+ char *host, IRS_GETNAMEINFO_BUFLEN_T hostlen,
+ char *serv, IRS_GETNAMEINFO_BUFLEN_T servlen,
+ IRS_GETNAMEINFO_FLAGS_T flags)
+{
+ struct afd *afd = NULL;
+ struct servent *sp;
+ unsigned short port = 0;
+#ifdef IRS_PLATFORM_HAVESALEN
+ size_t len;
+#endif
+ int family, i;
+ const void *addr = NULL;
+ char *p;
+#if 0
+ unsigned long v4a;
+ unsigned char pfx;
+#endif
+ char numserv[sizeof("65000")];
+ char numaddr[sizeof("abcd:abcd:abcd:abcd:abcd:abcd:255.255.255.255")
+ + 1 + sizeof("4294967295")];
+ const char *proto;
+ int result = SUCCESS;
+
+ if (sa == NULL)
+ ERR(EAI_FAIL);
+
+#ifdef IRS_PLATFORM_HAVESALEN
+ len = sa->sa_len;
+ if (len != salen)
+ ERR(EAI_FAIL);
+#endif
+
+ family = sa->sa_family;
+ for (i = 0; afdl[i].a_af; i++)
+ if (afdl[i].a_af == family) {
+ afd = &afdl[i];
+ goto found;
+ }
+ ERR(EAI_FAMILY);
+
+ found:
+ if (salen != afd->a_socklen)
+ ERR(EAI_FAIL);
+
+ switch (family) {
+ case AF_INET:
+ port = ((const struct sockaddr_in *)sa)->sin_port;
+ addr = &((const struct sockaddr_in *)sa)->sin_addr.s_addr;
+ break;
+
+ case AF_INET6:
+ port = ((const struct sockaddr_in6 *)sa)->sin6_port;
+ addr = ((const struct sockaddr_in6 *)sa)->sin6_addr.s6_addr;
+ break;
+
+ default:
+ INSIST(0);
+ }
+ proto = (flags & NI_DGRAM) ? "udp" : "tcp";
+
+ if (serv == NULL || servlen == 0U) {
+ /*
+ * Caller does not want service.
+ */
+ } else if ((flags & NI_NUMERICSERV) != 0 ||
+ (sp = getservbyport(port, proto)) == NULL) {
+ snprintf(numserv, sizeof(numserv), "%d", ntohs(port));
+ if ((strlen(numserv) + 1) > servlen)
+ ERR(EAI_OVERFLOW);
+ strlcpy(serv, numserv, servlen);
+ } else {
+ if ((strlen(sp->s_name) + 1) > servlen)
+ ERR(EAI_OVERFLOW);
+ strlcpy(serv, sp->s_name, servlen);
+ }
+
+#if 0
+ switch (sa->sa_family) {
+ case AF_INET:
+ v4a = ((struct sockaddr_in *)sa)->sin_addr.s_addr;
+ if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
+ flags |= NI_NUMERICHOST;
+ v4a >>= IN_CLASSA_NSHIFT;
+ if (v4a == 0 || v4a == IN_LOOPBACKNET)
+ flags |= NI_NUMERICHOST;
+ break;
+
+ case AF_INET6:
+ pfx = ((struct sockaddr_in6 *)sa)->sin6_addr.s6_addr[0];
+ if (pfx == 0 || pfx == 0xfe || pfx == 0xff)
+ flags |= NI_NUMERICHOST;
+ break;
+ }
+#endif
+
+ if (host == NULL || hostlen == 0U) {
+ /*
+ * do nothing in this case.
+ * in case you are wondering if "&&" is more correct than
+ * "||" here: RFC3493 says that host == NULL or hostlen == 0
+ * means that the caller does not want the result.
+ */
+ } else if ((flags & NI_NUMERICHOST) != 0) {
+ if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
+ == NULL)
+ ERR(EAI_SYSTEM);
+#if defined(IRS_HAVE_SIN6_SCOPE_ID)
+ if (afd->a_af == AF_INET6 &&
+ ((const struct sockaddr_in6 *)sa)->sin6_scope_id) {
+ char *p = numaddr + strlen(numaddr);
+ const char *stringscope = NULL;
+#ifdef VENDOR_SPECIFIC
+ /*
+ * Vendors may want to add support for
+ * non-numeric scope identifier.
+ */
+ stringscope = foo;
+#endif
+ if (stringscope == NULL) {
+ snprintf(p, sizeof(numaddr) - (p - numaddr),
+ "%%%u",
+ ((const struct sockaddr_in6 *)sa)->sin6_scope_id);
+ } else {
+ snprintf(p, sizeof(numaddr) - (p - numaddr),
+ "%%%s", stringscope);
+ }
+ }
+#endif
+ if (strlen(numaddr) + 1 > hostlen)
+ ERR(EAI_OVERFLOW);
+ strlcpy(host, numaddr, hostlen);
+ } else {
+ isc_netaddr_t netaddr;
+ dns_fixedname_t ptrfname;
+ dns_name_t *ptrname;
+ irs_context_t *irsctx = NULL;
+ dns_client_t *client;
+ bool found = false;
+ dns_namelist_t answerlist;
+ dns_rdataset_t *rdataset;
+ isc_region_t hostregion;
+ char hoststr[1024]; /* is this enough? */
+ isc_result_t iresult;
+
+ /* Get IRS context and the associated DNS client object */
+ iresult = irs_context_get(&irsctx);
+ if (iresult != ISC_R_SUCCESS)
+ ERR(EAI_FAIL);
+ client = irs_context_getdnsclient(irsctx);
+
+ /* Make query name */
+ isc_netaddr_fromsockaddr(&netaddr, (const isc_sockaddr_t *)sa);
+ ptrname = dns_fixedname_initname(&ptrfname);
+ iresult = dns_byaddr_createptrname2(&netaddr, 0, ptrname);
+ if (iresult != ISC_R_SUCCESS)
+ ERR(EAI_FAIL);
+
+ /* Get the PTR RRset */
+ ISC_LIST_INIT(answerlist);
+ iresult = dns_client_resolve(client, ptrname,
+ dns_rdataclass_in,
+ dns_rdatatype_ptr,
+ DNS_CLIENTRESOPT_ALLOWRUN,
+ &answerlist);
+ switch (iresult) {
+ case ISC_R_SUCCESS:
+ /*
+ * a 'non-existent' error is not necessarily fatal for
+ * getnameinfo().
+ */
+ case DNS_R_NCACHENXDOMAIN:
+ case DNS_R_NCACHENXRRSET:
+ break;
+ 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:
+ /*
+ * Don't use ERR as GCC 7 wants to raise a
+ * warning with ERR about possible falling
+ * through which is impossible.
+ */
+ result = EAI_INSECUREDATA;
+ goto cleanup;
+ default:
+ ERR(EAI_FAIL);
+ }
+
+ /* Parse the answer for the hostname */
+ for (ptrname = ISC_LIST_HEAD(answerlist); ptrname != NULL;
+ ptrname = ISC_LIST_NEXT(ptrname, link)) {
+ for (rdataset = ISC_LIST_HEAD(ptrname->list);
+ rdataset != NULL;
+ rdataset = ISC_LIST_NEXT(rdataset, link)) {
+ if (!dns_rdataset_isassociated(rdataset))
+ continue;
+ if (rdataset->type != dns_rdatatype_ptr)
+ continue;
+
+ for (iresult = dns_rdataset_first(rdataset);
+ iresult == ISC_R_SUCCESS;
+ iresult = dns_rdataset_next(rdataset)) {
+ dns_rdata_t rdata;
+ dns_rdata_ptr_t rdata_ptr;
+ isc_buffer_t b;
+
+ dns_rdata_init(&rdata);
+ dns_rdataset_current(rdataset, &rdata);
+ dns_rdata_tostruct(&rdata, &rdata_ptr,
+ NULL);
+
+ isc_buffer_init(&b, hoststr,
+ sizeof(hoststr));
+ iresult =
+ dns_name_totext(&rdata_ptr.ptr,
+ true, &b);
+ dns_rdata_freestruct(&rdata_ptr);
+ if (iresult == ISC_R_SUCCESS) {
+ /*
+ * We ignore the rest of the
+ * answer. After all,
+ * getnameinfo() can return
+ * at most one hostname.
+ */
+ found = true;
+ isc_buffer_usedregion(
+ &b, &hostregion);
+ goto ptrfound;
+ }
+
+ }
+ }
+ }
+ ptrfound:
+ dns_client_freeresanswer(client, &answerlist);
+ if (found) {
+ if ((flags & NI_NOFQDN) != 0) {
+ p = strchr(hoststr, '.');
+ if (p)
+ *p = '\0';
+ }
+ if (hostregion.length + 1 > hostlen)
+ ERR(EAI_OVERFLOW);
+ snprintf(host, hostlen, "%.*s",
+ (int)hostregion.length,
+ (char *)hostregion.base);
+ } else {
+ if ((flags & NI_NAMEREQD) != 0)
+ ERR(EAI_NONAME);
+ if (inet_ntop(afd->a_af, addr, numaddr,
+ sizeof(numaddr)) == NULL)
+ ERR(EAI_SYSTEM);
+ if ((strlen(numaddr) + 1) > hostlen)
+ ERR(EAI_OVERFLOW);
+ strlcpy(host, numaddr, hostlen);
+ }
+ }
+ result = SUCCESS;
+
+ cleanup:
+ return (result);
+}
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