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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-05 18:37:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-05 18:37:14 +0000 |
commit | ea648e70a989cca190cd7403fe892fd2dcc290b4 (patch) | |
tree | e2b6b1c647da68b0d4d66082835e256eb30970e8 /lib/lwres/getnameinfo.c | |
parent | Initial commit. (diff) | |
download | bind9-ea648e70a989cca190cd7403fe892fd2dcc290b4.tar.xz bind9-ea648e70a989cca190cd7403fe892fd2dcc290b4.zip |
Adding upstream version 1:9.11.5.P4+dfsg.upstream/1%9.11.5.P4+dfsgupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/lwres/getnameinfo.c')
-rw-r--r-- | lib/lwres/getnameinfo.c | 342 |
1 files changed, 342 insertions, 0 deletions
diff --git a/lib/lwres/getnameinfo.c b/lib/lwres/getnameinfo.c new file mode 100644 index 0000000..9951f4c --- /dev/null +++ b/lib/lwres/getnameinfo.c @@ -0,0 +1,342 @@ +/* + * Portions 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. + */ + +/* $Id$ */ + +/*! \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. + */ + +/* + * XXX + * Issues to be discussed: + * - Return values. There seems to be no standard for return value (RFC2553) + * but INRIA implementation returns EAI_xxx defined for getaddrinfo(). + */ + + +/** + * This function is equivalent to the getnameinfo(3) function defined in + * RFC2133. lwres_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 + * + * lwres_getnameinfo() returns 0 on success or a non-zero error code if + * an error occurs. + * + * \section getname_see See Also + * + * RFC2133, getservbyport(), + * lwres_getnamebyaddr(). lwres_net_ntop(). + * + * \section getnameinfo_bugs Bugs + * + * RFC2133 fails to define what the nonzero return values of + * getnameinfo() are. + */ + +#include <config.h> + +#include <inttypes.h> +#include <stdio.h> +#include <string.h> + +#include <lwres/lwres.h> +#include <lwres/net.h> +#include <lwres/netdb.h> +#include "print_p.h" + +#include "assert_p.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}, +}; + +#define ENI_NOSERVNAME 1 +#define ENI_NOHOSTNAME 2 +#define ENI_MEMORY 3 +#define ENI_SYSTEM 4 +#define ENI_FAMILY 5 +#define ENI_SALEN 6 +#define ENI_NOSOCKET 7 + +/*! + * 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) + +/*% lightweight resolver socket address structure to hostname and service name */ +int +lwres_getnameinfo(const struct sockaddr *sa, size_t salen, char *host, + size_t hostlen, char *serv, size_t servlen, int flags) +{ + struct afd *afd = NULL; + struct servent *sp; + unsigned short port; +#ifdef LWRES_PLATFORM_HAVESALEN + size_t len; +#endif + int family, i; + const void *addr; + 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; + uint32_t lwf = 0; + lwres_context_t *lwrctx = NULL; + lwres_gnbaresponse_t *by = NULL; + int result = SUCCESS; + int n; + + if (sa == NULL) + ERR(ENI_NOSOCKET); + +#ifdef LWRES_PLATFORM_HAVESALEN + len = sa->sa_len; + if (len != salen) + ERR(ENI_SALEN); +#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(ENI_FAMILY); + + found: + if (salen != afd->a_socklen) + ERR(ENI_SALEN); + + 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: + port = 0; + addr = NULL; + POST(port); POST(addr); + 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(ENI_MEMORY); + strcpy(serv, numserv); + } else { + if ((strlen(sp->s_name) + 1) > servlen) + ERR(ENI_MEMORY); + strcpy(serv, sp->s_name); + } + +#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) { + /* + * What should we do? + */ + } else if (flags & NI_NUMERICHOST) { + if (lwres_net_ntop(afd->a_af, addr, numaddr, sizeof(numaddr)) + == NULL) + ERR(ENI_SYSTEM); +#if defined(LWRES_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; +#if 0 + if ((flags & NI_NUMERICSCOPE) == 0) { + /* + * 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(ENI_MEMORY); + strcpy(host, numaddr); + } else { + switch (family) { + case AF_INET: + lwf = LWRES_ADDRTYPE_V4; + break; + case AF_INET6: + lwf = LWRES_ADDRTYPE_V6; + break; + default: + INSIST(0); + } + + n = lwres_context_create(&lwrctx, NULL, NULL, NULL, 0); + if (n == 0) + (void) lwres_conf_parse(lwrctx, lwres_resolv_conf); + + if (n == 0) + n = lwres_getnamebyaddr(lwrctx, lwf, + (uint16_t)afd->a_addrlen, + addr, &by); + if (n == 0) { + if (flags & NI_NOFQDN) { + p = strchr(by->realname, '.'); + if (p) + *p = '\0'; + } + if ((strlen(by->realname) + 1) > hostlen) + ERR(ENI_MEMORY); + strcpy(host, by->realname); + } else { + if (flags & NI_NAMEREQD) + ERR(ENI_NOHOSTNAME); + if (lwres_net_ntop(afd->a_af, addr, numaddr, + sizeof(numaddr)) + == NULL) + ERR(ENI_NOHOSTNAME); + if ((strlen(numaddr) + 1) > hostlen) + ERR(ENI_MEMORY); + strcpy(host, numaddr); + } + } + result = SUCCESS; + cleanup: + if (by != NULL) + lwres_gnbaresponse_free(lwrctx, &by); + if (lwrctx != NULL) { + lwres_conf_clear(lwrctx); + lwres_context_destroy(&lwrctx); + } + return (result); +} |