/* * Copyright (C) 2004, 2005, 2007 Internet Systems Consortium, Inc. ("ISC") * Copyright (C) 2000, 2001 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: lwpacket.c,v 1.18 2007/06/19 23:47:22 tbox Exp $ */ /*! \file */ /** * These functions rely on a struct lwres_lwpacket which is defined in * \link lwpacket.h lwres/lwpacket.h.\endlink * * The following opcodes are currently defined: * * \li #LWRES_OPCODE_NOOP * Success is always returned and the packet contents are * echoed. The \link lwres_noop.c lwres_noop_*()\endlink functions should be used for this * type. * * \li #LWRES_OPCODE_GETADDRSBYNAME * returns all known addresses for a given name. The * \link lwres_gabn.c lwres_gabn_*()\endlink functions should be used for this type. * * \li #LWRES_OPCODE_GETNAMEBYADDR * return the hostname for the given address. The * \link lwres_gnba.c lwres_gnba_*() \endlink functions should be used for this type. * * lwres_lwpacket_renderheader() transfers the contents of lightweight * resolver packet structure #lwres_lwpacket_t *pkt in network byte * order to the lightweight resolver buffer, *b. * * lwres_lwpacket_parseheader() performs the converse operation. It * transfers data in network byte order from buffer *b to resolver * packet *pkt. The contents of the buffer b should correspond to a * #lwres_lwpacket_t. * * \section lwpacket_return Return Values * * Successful calls to lwres_lwpacket_renderheader() and * lwres_lwpacket_parseheader() return #LWRES_R_SUCCESS. If there is * insufficient space to copy data between the buffer *b and * lightweight resolver packet *pkt both functions return * #LWRES_R_UNEXPECTEDEND. */ #include <config.h> #include <assert.h> #include <stdlib.h> #include <string.h> #include <lwres/lwbuffer.h> #include <lwres/lwpacket.h> #include <lwres/result.h> #include "assert_p.h" /*% Length of Packet */ #define LWPACKET_LENGTH \ (sizeof(lwres_uint16_t) * 4 + sizeof(lwres_uint32_t) * 5) /*% transfers the contents of lightweight resolver packet structure lwres_lwpacket_t *pkt in network byte order to the lightweight resolver buffer, *b. */ lwres_result_t lwres_lwpacket_renderheader(lwres_buffer_t *b, lwres_lwpacket_t *pkt) { REQUIRE(b != NULL); REQUIRE(pkt != NULL); if (!SPACE_OK(b, LWPACKET_LENGTH)) return (LWRES_R_UNEXPECTEDEND); lwres_buffer_putuint32(b, pkt->length); lwres_buffer_putuint16(b, pkt->version); lwres_buffer_putuint16(b, pkt->pktflags); lwres_buffer_putuint32(b, pkt->serial); lwres_buffer_putuint32(b, pkt->opcode); lwres_buffer_putuint32(b, pkt->result); lwres_buffer_putuint32(b, pkt->recvlength); lwres_buffer_putuint16(b, pkt->authtype); lwres_buffer_putuint16(b, pkt->authlength); return (LWRES_R_SUCCESS); } /*% transfers data in network byte order from buffer *b to resolver packet *pkt. The contents of the buffer b should correspond to a lwres_lwpacket_t. */ lwres_result_t lwres_lwpacket_parseheader(lwres_buffer_t *b, lwres_lwpacket_t *pkt) { lwres_uint32_t space; REQUIRE(b != NULL); REQUIRE(pkt != NULL); space = LWRES_BUFFER_REMAINING(b); if (space < LWPACKET_LENGTH) return (LWRES_R_UNEXPECTEDEND); pkt->length = lwres_buffer_getuint32(b); /* * XXXBEW/MLG Checking that the buffer is long enough probably * shouldn't be done here, since this function is supposed to just * parse the header. */ if (pkt->length > space) return (LWRES_R_UNEXPECTEDEND); pkt->version = lwres_buffer_getuint16(b); pkt->pktflags = lwres_buffer_getuint16(b); pkt->serial = lwres_buffer_getuint32(b); pkt->opcode = lwres_buffer_getuint32(b); pkt->result = lwres_buffer_getuint32(b); pkt->recvlength = lwres_buffer_getuint32(b); pkt->authtype = lwres_buffer_getuint16(b); pkt->authlength = lwres_buffer_getuint16(b); return (LWRES_R_SUCCESS); }