/* Copyright (C) 1996 Free Software Foundation, Inc. This file is part of the GNU C Library. Extended from original form by Ulrich Drepper , 1996. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with the GNU C Library; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* Parts of this file are plain copies of the file `getnetnamadr.c' from the bind package and it has the following copyright. */ /* Copyright (c) 1993 Carlos Leandro and Rui Salgueiro * Dep. Matematica Universidade de Coimbra, Portugal, Europe * * 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. */ /* * Copyright (c) 1983, 1993 * The Regents of the University of California. 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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. */ #include #include #include #include #include #include #include "nsswitch.h" #include /* Maximum number of aliases we allow. */ #define MAX_NR_ALIASES 48 #if PACKETSZ > 1024 #define MAXPACKET PACKETSZ #else #define MAXPACKET 1024 #endif typedef enum { BYADDR, BYNAME } lookup_method; /* We need this time later. */ typedef union querybuf { HEADER hdr; u_char buf[MAXPACKET]; } querybuf; /* Protortypes for local functions. */ static int getanswer_r (const querybuf *answer, int anslen, struct netent *result, char *buffer, int buflen, lookup_method net_i); int _nss_dns_getnetbyname_r (const char *name, struct netent *result, char *buffer, int buflen) { /* Return entry for network with NAME. */ querybuf net_buffer; int anslen; char *qbuf; qbuf = strdupa (name); anslen = res_search (qbuf, C_IN, T_PTR, (u_char *) &net_buffer, sizeof (querybuf)); if (anslen < 0) /* Nothing found. */ return (errno == ECONNREFUSED || errno == EPFNOSUPPORT || errno == EAFNOSUPPORT) ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND; return getanswer_r (&net_buffer, anslen, result, buffer, buflen, BYNAME); } int _nss_dns_getnetbyaddr_r (long net, int type, struct netent *result, char *buffer, int buflen) { /* Return entry for network with NAME. */ int status; querybuf net_buffer; unsigned int net_bytes[4]; char qbuf[MAXDNAME]; int cnt, anslen; u_int32_t net2; /* No net address lookup for IPv6 yet. */ if (type != AF_INET) return NSS_STATUS_UNAVAIL; net2 = (u_int32_t) net; for (cnt = 4; net2 != 0; net2 >>= 8) net_bytes[--cnt] = net2 & 0xff; switch (cnt) { case 3: /* Class A network. */ sprintf (qbuf, "0.0.0.%u.in-addr.arpa", net_bytes[3]); break; case 2: /* Class B network. */ sprintf (qbuf, "0.0.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2]); break; case 1: /* Class C network. */ sprintf (qbuf, "0.%u.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2], net_bytes[1]); break; case 0: /* Class D - E network. */ sprintf (qbuf, "%u.%u.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2], net_bytes[1], net_bytes[0]); break; } anslen = res_query (qbuf, C_IN, T_PTR, (u_char *) &net_buffer, sizeof (querybuf)); if (anslen < 0) /* Nothing found. */ return (errno == ECONNREFUSED || errno == EPFNOSUPPORT || errno == EAFNOSUPPORT) ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND; status = getanswer_r (&net_buffer, anslen, result, buffer, buflen, BYADDR); if (status == NSS_STATUS_SUCCESS) { /* Strip trailing zeros. */ unsigned int u_net = net; /* Maybe net should be unsigned? */ while ((u_net & 0xff) == 0 && u_net != 0) u_net >>= 8; result->n_net = u_net; } return status; } #undef offsetof #define offsetof(Type, Member) ((size_t) &((Type *) NULL)->Member) static int getanswer_r (const querybuf *answer, int anslen, struct netent *result, char *buffer, int buflen, lookup_method net_i) { /* * Find first satisfactory answer * * answer --> +------------+ ( MESSAGE ) * | Header | * +------------+ * | Question | the question for the name server * +------------+ * | Answer | RRs answering the question * +------------+ * | Authority | RRs pointing toward an authority * | Additional | RRs holding additional information * +------------+ */ struct net_data { char *aliases[MAX_NR_ALIASES]; char linebuffer[0]; } *net_data = (struct net_data *) buffer; int linebuflen = buflen - offsetof (struct net_data, linebuffer); const char *end_of_message = &answer->buf[anslen]; const HEADER *header_pointer = &answer->hdr; /* #/records in the answer section. */ int answer_count = ntohs (header_pointer->ancount); /* #/entries in the question section. */ int question_count = ntohs (header_pointer->qdcount); char *bp = net_data->linebuffer; const char *cp = &answer->buf[HFIXEDSZ]; char **alias_pointer; int have_answer; char *ans; if (question_count == 0) /* FIXME: the Sun version uses for host name lookup an additional parameter for pointing to h_errno. this is missing here. OSF/1 has a per-thread h_errno variable. */ if (header_pointer->aa != 0) { __set_h_errno (HOST_NOT_FOUND); return NSS_STATUS_NOTFOUND; } else { __set_h_errno (TRY_AGAIN); return NSS_STATUS_TRYAGAIN; } /* Skip the question part. */ while (question_count-- > 0) cp += __dn_skipname (cp, end_of_message) + QFIXEDSZ; alias_pointer = result->n_aliases = &net_data->aliases[0]; *alias_pointer = NULL; have_answer = 0; ans = NULL; while (--answer_count >= 0 && cp < end_of_message) { int n = dn_expand (answer->buf, end_of_message, cp, bp, linebuflen); int type, class; if (n < 0 || res_dnok (bp) == 0) break; cp += n; ans = strdupa (bp); GETSHORT (type, cp); GETSHORT (class, cp); cp += INT32SZ; /* TTL */ GETSHORT (n, cp); if (class == C_IN && type == T_PTR) { n = dn_expand (answer->buf, end_of_message, cp, bp, linebuflen); if (n < 0 || !res_hnok (bp)) { /* XXX What does this mean? The original form from bind returns NULL. Incrementing cp has no effect in any case. What should I return here. ??? */ cp += n; return NSS_STATUS_UNAVAIL; } cp += n; *alias_pointer++ = bp; bp += strlen (bp) + 1; result->n_addrtype = class == C_IN ? AF_INET : AF_UNSPEC; ++have_answer; } } if (have_answer) { char *tmp; int len; char *in, *cp, *rp, *wp; int cnt, first_flag; *alias_pointer = NULL; switch (net_i) { case BYADDR: result->n_name = result->n_aliases[0]; result->n_net = 0L; break; case BYNAME: len = strlen (result->n_aliases[0]); tmp = (char *) alloca (len + 1); tmp[len] = 0; wp = &tmp[len - 1]; rp = in = result->n_aliases[0]; result->n_name = ans; first_flag = 1; for (cnt = 0; cnt < 4; ++cnt) { char *startp; startp = rp; while (*rp != '.') ++rp; if (rp - startp > 1 || *startp != '0' || !first_flag) { first_flag = 0; if (cnt > 0) *wp-- = '.'; cp = rp; while (cp > startp) *wp-- = *--cp; } in = rp + 1; } result->n_net = inet_network (wp); break; } ++result->n_aliases; return NSS_STATUS_SUCCESS; } __set_h_errno (TRY_AGAIN); return NSS_STATUS_TRYAGAIN; }