Edit File: lwpacket.h
/* * Copyright (C) Internet Systems Consortium, Inc. ("ISC") * * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. * * See the COPYRIGHT file distributed with this work for additional * information regarding copyright ownership. */ /* $Id: lwpacket.h,v 1.24 2007/06/19 23:47:23 tbox Exp $ */ #ifndef LWRES_LWPACKET_H #define LWRES_LWPACKET_H 1 #include <lwres/lang.h> #include <lwres/lwbuffer.h> #include <lwres/result.h> /*% lwres_lwpacket_t */ typedef struct lwres_lwpacket lwres_lwpacket_t; /*% lwres_lwpacket structure */ struct lwres_lwpacket { /*! The overall packet length, including the * entire packet header. * This field is filled in by the * \link lwres_gabn.c lwres_gabn_*()\endlink * and \link lwres_gnba.c lwres_gnba_*()\endlink calls. */ lwres_uint32_t length; /*! Specifies the header format. Currently, * there is only one format, #LWRES_LWPACKETVERSION_0. * This field is filled in by the * \link lwres_gabn.c lwres_gabn_*()\endlink * and \link lwres_gnba.c lwres_gnba_*()\endlink calls. */ lwres_uint16_t version; /*! Specifies library-defined flags for this packet, such as * whether the packet is a request or a reply. None of * these are definable by the caller, but library-defined values * can be set by the caller. For example, one bit in this field * indicates if the packet is a request or a response. * This field is filled in by * the application wits the exception of the * #LWRES_LWPACKETFLAG_RESPONSE bit, which is set by the library * in the * \link lwres_gabn.c lwres_gabn_*()\endlink * and \link lwres_gnba.c lwres_gnba_*()\endlink calls. */ lwres_uint16_t pktflags; /*! Set by the requestor and is returned in all replies. * If two packets from the same source have the same serial * number and are from the same source, they are assumed to * be duplicates and the latter ones may be dropped. * (The library does not do this by default on replies, but * does so on requests.) */ lwres_uint32_t serial; /*! Opcodes between 0x04000000 and 0xffffffff * are application defined. Opcodes between * 0x00000000 and 0x03ffffff are * reserved for library use. * This field is filled in by the * \link lwres_gabn.c lwres_gabn_*()\endlink * and \link lwres_gnba.c lwres_gnba_*()\endlink calls. */ lwres_uint32_t opcode; /*! Only valid for results. * Results between 0x04000000 and 0xffffffff are application * defined. * Results between 0x00000000 and 0x03ffffff are reserved for * library use. * (This is the same reserved range defined in <isc/resultclass.h>, * so it * would be trivial to map ISC_R_* result codes into packet result * codes when appropriate.) * This field is filled in by the * \link lwres_gabn.c lwres_gabn_*()\endlink * and \link lwres_gnba.c lwres_gnba_*()\endlink calls. */ lwres_uint32_t result; /*! Set to the maximum buffer size that the receiver can * handle on requests, and the size of the buffer needed to * satisfy a request * when the buffer is too large for replies. * This field is supplied by the application. */ lwres_uint32_t recvlength; /*! The packet level auth type used. * Authtypes between 0x1000 and 0xffff are application defined. * Authtypes * between 0x0000 and 0x0fff are reserved for library use. * This is currently * unused and MUST be set to zero. */ lwres_uint16_t authtype; /*! The length of the authentication data. * See the specific * authtypes for more information on what is contained * in this field. This is currently unused, and * MUST be set to zero. */ lwres_uint16_t authlength; }; #define LWRES_LWPACKET_LENGTH (4 * 5 + 2 * 4) /*%< Overall length. */ #define LWRES_LWPACKETFLAG_RESPONSE 0x0001U /*%< If set, pkt is a response. */ #define LWRES_LWPACKETVERSION_0 0 /*%< Header format. */ /*! \file lwres/lwpacket.h * * * The remainder of the packet consists of two regions, one described by * "authlen" and one of "length - authlen - sizeof(lwres_lwpacket_t)". * * That is: * * \code * pkt header * authlen bytes of auth information * data bytes * \endcode * * Currently defined opcodes: * *\li #LWRES_OPCODE_NOOP. Success is always returned, with the packet contents echoed. * *\li #LWRES_OPCODE_GETADDRSBYNAME. Return all known addresses for a given name. * This may return NIS or /etc/hosts info as well as DNS * information. Flags will be provided to indicate ip4/ip6 * addresses are desired. * *\li #LWRES_OPCODE_GETNAMEBYADDR. Return the hostname for the given address. Once * again, it will return data from multiple sources. */ LWRES_LANG_BEGINDECLS /* XXXMLG document */ lwres_result_t lwres_lwpacket_renderheader(lwres_buffer_t *b, lwres_lwpacket_t *pkt); lwres_result_t lwres_lwpacket_parseheader(lwres_buffer_t *b, lwres_lwpacket_t *pkt); LWRES_LANG_ENDDECLS #endif /* LWRES_LWPACKET_H */