/* * Portions Copyright (C) 2004, 2005, 2007, 2011, 2012 Internet Systems Consortium, Inc. ("ISC") * Portions Copyright (C) 1999-2001, 2003 Internet Software Consortium. * * Permission to use, copy, modify, and/or 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. */ /* $Id$ */ /*! \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 <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; 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; lwres_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, (lwres_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); }