/* $NetBSD: res_mkquery.c,v 1.16 2017/09/28 23:32:01 christos Exp $ */ /* * Portions Copyright (C) 2004, 2005, 2008 Internet Systems Consortium, Inc. ("ISC") * Portions Copyright (C) 1996, 1997, 1988, 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. */ /* * Copyright (c) 1985, 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. 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. */ #include <sys/cdefs.h> #if defined(LIBC_SCCS) && !defined(lint) #ifdef notdef static const char sccsid[] = "@(#)res_mkquery.c 8.1 (Berkeley) 6/4/93"; static const char rcsid[] = "Id: res_mkquery.c,v 1.10 2008/12/11 09:59:00 marka Exp"; #else __RCSID("$NetBSD: res_mkquery.c,v 1.16 2017/09/28 23:32:01 christos Exp $"); #endif #endif /* LIBC_SCCS and not lint */ #include "port_before.h" #include <sys/types.h> #include <sys/param.h> #include <netinet/in.h> #include <arpa/nameser.h> #include <assert.h> #include <netdb.h> #include <resolv.h> #include <stdio.h> #include <string.h> #include "port_after.h" /* Options. Leave them on. */ //#define DEBUG extern const char *_res_opcodes[]; /*% * Form all types of queries. * Returns the size of the result or -1. */ int res_nmkquery(res_state statp, int op, /*!< opcode of query */ const char *dname, /*!< domain name */ int class, int type, /*!< class and type of query */ const u_char *data, /*!< resource record data */ int datalen, /*!< length of data */ const u_char *newrr_in, /*!< new rr for modify or append */ u_char *buf, /*!< buffer to put query */ int buflen) /*!< size of buffer */ { register HEADER *hp; register u_char *cp, *ep; register int n; u_char *dnptrs[20], **dpp, **lastdnptr; UNUSED(newrr_in); #ifdef DEBUG if (statp->options & RES_DEBUG) printf(";; res_nmkquery(%s, %s, %s, %s)\n", _res_opcodes[op], dname, p_class(class), p_type(type)); #endif /* * Initialize header fields. */ if ((buf == NULL) || (buflen < HFIXEDSZ)) return (-1); memset(buf, 0, HFIXEDSZ); hp = (HEADER *)(void *)buf; statp->id = res_nrandomid(statp); hp->id = htons(statp->id); hp->opcode = op; hp->rd = (statp->options & RES_RECURSE) != 0U; hp->ad = (statp->options & RES_USE_DNSSEC) != 0U; hp->rcode = NOERROR; cp = buf + HFIXEDSZ; ep = buf + buflen; dpp = dnptrs; *dpp++ = buf; *dpp++ = NULL; lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0]; /* * perform opcode specific processing */ switch (op) { case QUERY: /*FALLTHROUGH*/ case NS_NOTIFY_OP: if (ep - cp < QFIXEDSZ) return (-1); if ((n = dn_comp(dname, cp, (int)(ep - cp - QFIXEDSZ), dnptrs, lastdnptr)) < 0) return (-1); cp += n; ns_put16(type, cp); cp += INT16SZ; ns_put16(class, cp); cp += INT16SZ; hp->qdcount = htons(1); if (op == QUERY || data == NULL) break; /* * Make an additional record for completion domain. */ if ((ep - cp) < RRFIXEDSZ) return (-1); n = dn_comp((const char *)data, cp, (int)(ep - cp - RRFIXEDSZ), dnptrs, lastdnptr); if (n < 0) return (-1); cp += n; ns_put16(T_NULL, cp); cp += INT16SZ; ns_put16(class, cp); cp += INT16SZ; ns_put32(0, cp); cp += INT32SZ; ns_put16(0, cp); cp += INT16SZ; hp->arcount = htons(1); break; case IQUERY: /* * Initialize answer section */ if (ep - cp < 1 + RRFIXEDSZ + datalen) return (-1); *cp++ = '\0'; /*%< no domain name */ ns_put16(type, cp); cp += INT16SZ; ns_put16(class, cp); cp += INT16SZ; ns_put32(0, cp); cp += INT32SZ; ns_put16(datalen, cp); cp += INT16SZ; if (datalen) { memcpy(cp, data, (size_t)datalen); cp += datalen; } hp->ancount = htons(1); break; default: return (-1); } assert(INT_MIN <= (cp - buf) && (cp - buf) <= INT_MAX); return (int)(cp - buf); } #ifdef RES_USE_EDNS0 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */ int res_nopt(res_state statp, int n0, /*%< current offset in buffer */ u_char *buf, /*%< buffer to put query */ int buflen, /*%< size of buffer */ int anslen) /*%< UDP answer buffer size */ { register HEADER *hp; register u_char *cp, *ep; u_int16_t flags = 0; #ifdef DEBUG if ((statp->options & RES_DEBUG) != 0U) printf(";; res_nopt()\n"); #endif hp = (HEADER *)(void *)buf; cp = buf + n0; ep = buf + buflen; if ((ep - cp) < 1 + RRFIXEDSZ) return (-1); *cp++ = 0; /*%< "." */ ns_put16(ns_t_opt, cp); /*%< TYPE */ cp += INT16SZ; if (anslen > 0xffff) anslen = 0xffff; ns_put16(anslen, cp); /*%< CLASS = UDP payload size */ cp += INT16SZ; *cp++ = NOERROR; /*%< extended RCODE */ *cp++ = 0; /*%< EDNS version */ if (statp->options & RES_USE_DNSSEC) { #ifdef DEBUG if (statp->options & RES_DEBUG) printf(";; res_opt()... ENDS0 DNSSEC\n"); #endif flags |= NS_OPT_DNSSEC_OK; } ns_put16(flags, cp); cp += INT16SZ; ns_put16(0U, cp); /*%< RDLEN */ cp += INT16SZ; hp->arcount = htons(ntohs(hp->arcount) + 1); assert(INT_MIN <= (cp - buf) && (cp - buf) <= INT_MAX); return (int)(cp - buf); } /* * Construct variable data (RDATA) block for OPT psuedo-RR, append it * to the buffer, then update the RDLEN field (previously set to zero by * res_nopt()) with the new RDATA length. */ int res_nopt_rdata(res_state statp, int n0, /*%< current offset in buffer */ u_char *buf, /*%< buffer to put query */ int buflen, /*%< size of buffer */ u_char *rdata, /*%< ptr to start of opt rdata */ u_short code, /*%< OPTION-CODE */ u_short len, /*%< OPTION-LENGTH */ u_char *data) /*%< OPTION_DATA */ { register u_char *cp, *ep; #ifdef DEBUG if ((statp->options & RES_DEBUG) != 0U) printf(";; res_nopt_rdata()\n"); #endif cp = buf + n0; ep = buf + buflen; if ((ep - cp) < (4 + len)) return (-1); if (rdata < (buf + 2) || rdata >= ep) return (-1); ns_put16(code, cp); cp += INT16SZ; ns_put16(len, cp); cp += INT16SZ; memcpy(cp, data, (size_t)len); cp += len; assert(0 <= (cp - rdata) && (cp - rdata) <= USHRT_MAX); len = (u_short)(cp - rdata); ns_put16(len, rdata - 2); /* Update RDLEN field */ assert(INT_MIN <= (cp - buf) && (cp - buf) <= INT_MAX); return (int)(cp - buf); } #endif /*! \file */
