/*- * Copyright (c) 1985, 1988, 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. * - * Portions Copyright (c) 1993 by Digital Equipment Corporation. * * 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, and that * the name of Digital Equipment Corporation not be used in advertising or * publicity pertaining to distribution of the document or software without * specific, written prior permission. * * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT * CORPORATION 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. * - * --Copyright-- */ /* Portions 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. */ #if defined(LIBC_SCCS) && !defined(lint) static char sccsid[] = "@(#)gethostnamadr.c 8.1 (Berkeley) 6/4/93"; static char rcsid[] = "$FreeBSD$"; #endif /* LIBC_SCCS and not lint */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "res_config.h" extern int h_errno; #define BYADDR 0 #define BYNAME 1 #define MAXALIASES 35 #if PACKETSZ > 1024 #define MAXPACKET PACKETSZ #else #define MAXPACKET 1024 #endif typedef union { HEADER hdr; u_char buf[MAXPACKET]; } querybuf; typedef union { long al; char ac; } align; static struct netent * getnetanswer(answer, anslen, net_i) querybuf *answer; int anslen; int net_i; { register HEADER *hp; register u_char *cp; register int n; u_char *eom; int type, class, buflen, ancount, qdcount, haveanswer, i, nchar; char aux1[30], aux2[30], ans[30], *in, *st, *pauxt, *bp, **ap, *paux1 = &aux1[0], *paux2 = &aux2[0], flag = 0; static struct netent net_entry; static char *net_aliases[MAXALIASES], netbuf[BUFSIZ+1]; /* * 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 * +------------+ */ eom = answer->buf + anslen; hp = &answer->hdr; ancount = ntohs(hp->ancount); /* #/records in the answer section */ qdcount = ntohs(hp->qdcount); /* #/entries in the question section */ bp = netbuf; buflen = sizeof(netbuf); cp = answer->buf + HFIXEDSZ; if (!qdcount) { if (hp->aa) h_errno = HOST_NOT_FOUND; else h_errno = TRY_AGAIN; return (NULL); } while (qdcount-- > 0) cp += __dn_skipname(cp, eom) + QFIXEDSZ; ap = net_aliases; *ap = NULL; net_entry.n_aliases = net_aliases; haveanswer = 0; while (--ancount >= 0 && cp < eom) { n = dn_expand(answer->buf, eom, cp, bp, buflen); if ((n < 0) || !res_dnok(bp)) break; cp += n; ans[0] = '\0'; (void)strcpy(&ans[0], 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, eom, cp, bp, buflen); if ((n < 0) || !res_hnok(bp)) { cp += n; return (NULL); } cp += n; *ap++ = bp; bp += strlen(bp) + 1; net_entry.n_addrtype = (class == C_IN) ? AF_INET : AF_UNSPEC; haveanswer++; } } if (haveanswer) { *ap = NULL; switch (net_i) { case BYADDR: net_entry.n_name = *net_entry.n_aliases; net_entry.n_net = 0L; break; case BYNAME: in = *net_entry.n_aliases; net_entry.n_name = &ans[0]; aux2[0] = '\0'; for (i = 0; i < 4; i++) { for (st = in, nchar = 0; *st != '.'; st++, nchar++) ; if (nchar != 1 || *in != '0' || flag) { flag = 1; (void)strncpy(paux1, (i==0) ? in : in-1, (i==0) ?nchar : nchar+1); paux1[(i==0) ? nchar : nchar+1] = '\0'; pauxt = paux2; paux2 = strcat(paux1, paux2); paux1 = pauxt; } in = ++st; } net_entry.n_net = inet_network(paux2); break; } net_entry.n_aliases++; return (&net_entry); } h_errno = TRY_AGAIN; return (NULL); } struct netent * _getnetbydnsaddr(net, net_type) register unsigned long net; register int net_type; { unsigned int netbr[4]; int nn, anslen; querybuf buf; char qbuf[MAXDNAME]; unsigned long net2; struct netent *net_entry; if (net_type != AF_INET) return (NULL); for (nn = 4, net2 = net; net2; net2 >>= 8) netbr[--nn] = net2 & 0xff; switch (nn) { case 3: /* Class A */ sprintf(qbuf, "0.0.0.%u.in-addr.arpa", netbr[3]); break; case 2: /* Class B */ sprintf(qbuf, "0.0.%u.%u.in-addr.arpa", netbr[3], netbr[2]); break; case 1: /* Class C */ sprintf(qbuf, "0.%u.%u.%u.in-addr.arpa", netbr[3], netbr[2], netbr[1]); break; case 0: /* Class D - E */ sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa", netbr[3], netbr[2], netbr[1], netbr[0]); break; } anslen = res_query(qbuf, C_IN, T_PTR, (u_char *)&buf, sizeof(buf)); if (anslen < 0) { #ifdef DEBUG if (_res.options & RES_DEBUG) printf("res_query failed\n"); #endif return (NULL); } net_entry = getnetanswer(&buf, anslen, BYADDR); if (net_entry) { unsigned u_net = net; /* maybe net should be unsigned ? */ /* Strip trailing zeros */ while ((u_net & 0xff) == 0 && u_net != 0) u_net >>= 8; net_entry->n_net = u_net; return (net_entry); } return (NULL); } struct netent * _getnetbydnsname(net) register const char *net; { int anslen; querybuf buf; char qbuf[MAXDNAME]; if ((_res.options & RES_INIT) == 0 && res_init() == -1) { h_errno = NETDB_INTERNAL; return (NULL); } strcpy(&qbuf[0], net); anslen = res_search(qbuf, C_IN, T_PTR, (u_char *)&buf, sizeof(buf)); if (anslen < 0) { #ifdef DEBUG if (_res.options & RES_DEBUG) printf("res_query failed\n"); #endif return (NULL); } return getnetanswer(&buf, anslen, BYNAME); } void _setnetdnsent(stayopen) int stayopen; { if (stayopen) _res.options |= RES_STAYOPEN | RES_USEVC; } void _endnetdnsent() { _res.options &= ~(RES_STAYOPEN | RES_USEVC); res_close(); }