XProtocol.hh

#ifndef __XPROTOCOL_H
#define __XPROTOCOL_H
/******************************************************************************/
/*                                                                            */
/*                          X P r o t o c o l . h h                           */
/*                                                                            */
/* (c) 2012 by the Board of Trustees of the Leland Stanford, Jr., University  */
/*                            All Rights Reserved                             */
/*   Produced by Andrew Hanushevsky for Stanford University under contract    */
/*              DE-AC02-76-SFO0515 with the Department of Energy              */
/*                                                                            */
/* This file is part of the XRootD software suite.                            */
/*                                                                            */
/* XRootD is free software: you can redistribute it and/or modify it under    */
/* the terms of the GNU Lesser General Public License as published by the     */
/* Free Software Foundation, either version 3 of the License, or (at your     */
/* option) any later version.                                                 */
/*                                                                            */
/* The XRootD protocol definition, documented in this file, is distributed    */
/* under a modified BSD license and may be freely used to reimplement it.     */
/* Any references to "source" in this license refers to this file or any      */
/* other file that specifically contains the following license.               */
/*                                                                            */
/* 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 copyright holder nor the names of its           */
/*    contributors may be used to endorse or promote products derived from    */
/*    this software without specific prior written permission.                */
/*                                                                            */
/* 4. Derived software may not use the name XRootD or cmsd (regardless of     */
/*    capitilization) in association with the derived work if the protocol    */
/*    documented in this file is changed in any way.                          */
/*                                                                            */
/*    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT    */
/*    HOLDER 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   */
/******************************************************************************/

//#ifndef __GNUC__
//#define __attribute__(x)
//#ifdef SUNCC
//#pragma pack(4)
//#endif
//#endif

#ifdef __CINT__
#define __attribute__(x)
#endif

// The following is the binary representation of the protocol version here.
// Protocol version is repesented as three base10 digits x.y.z with x having no
// upper limit (i.e. n.9.9 + 1 -> n+1.0.0). The kXR_PROTSIGNVERSION defines the
// protocol version where request signing became available.
//
#define kXR_PROTOCOLVERSION  0x00000400
#define kXR_PROTSIGNVERSION  0x00000310
#define kXR_PROTOCOLVSTRING "4.0.0"

#include "XProtocol/XPtypes.hh"

// KINDS of SERVERS
//
//
#define kXR_DataServer 1
#define kXR_LBalServer 0

// The below are defined for protocol version 2.9.7 or higher
// These are the flag value in the kXR_protool response
//
#define kXR_isManager 0x00000002
#define kXR_isServer  0x00000001
#define kXR_attrMeta  0x00000100
#define kXR_attrProxy 0x00000200
#define kXR_attrSuper 0x00000400

#define kXR_maxReqRetry 10

// Kind of error inside a XTNetFile's routine (temporary)
//
enum XReqErrorType {
   kGENERICERR = 0,    // Generic error
   kREAD,              // Error while reading from stream
   kWRITE,             // Error while writing to stream
   kREDIRCONNECT,      // Error redirecting to a given host
   kOK,                // Everything seems ok
   kNOMORESTREAMS      // No more available stream IDs for
                       // async processing
};

//______________________________________________
// PROTOCOL DEFINITION: CLIENT'S REQUESTS TYPES
//______________________________________________
// 
enum XRequestTypes {
   kXR_auth    =  3000,
   kXR_query,   // 3001
   kXR_chmod,   // 3002
   kXR_close,   // 3003
   kXR_dirlist, // 3004
   kXR_getfile, // 3005
   kXR_protocol,// 3006
   kXR_login,   // 3007
   kXR_mkdir,   // 3008
   kXR_mv,      // 3009
   kXR_open,    // 3010
   kXR_ping,    // 3011
   kXR_putfile, // 3012
   kXR_read,    // 3013
   kXR_rm,      // 3014
   kXR_rmdir,   // 3015
   kXR_sync,    // 3016
   kXR_stat,    // 3017
   kXR_set,     // 3018
   kXR_write,   // 3019
   kXR_admin,   // 3020
   kXR_prepare, // 3021
   kXR_statx,   // 3022
   kXR_endsess, // 3023
   kXR_bind,    // 3024
   kXR_readv,   // 3025
   kXR_verifyw, // 3026
   kXR_locate,  // 3027
   kXR_truncate,// 3028
   kXR_sigver,  // 3029
   kXR_decrypt, // 3030
   kXR_writev,  // 3031
   kXR_fattr,   // 3032
   kXR_REQFENCE // Always last valid request code +1
};

// OPEN MODE FOR A REMOTE FILE
enum XOpenRequestMode {
   kXR_ur = 0x100,
   kXR_uw = 0x080,
   kXR_ux = 0x040,
   kXR_gr = 0x020,
   kXR_gw = 0x010,
   kXR_gx = 0x008,
   kXR_or = 0x004,
   kXR_ow = 0x002,
   kXR_ox = 0x001
};

enum XMkdirOptions {
   kXR_mknone  = 0,
   kXR_mkdirpath  = 1
};

// this is a bitmask
enum XLoginAbility {
   kXR_nothing =   0,
   kXR_fullurl =   1,
   kXR_multipr =   3,
   kXR_readrdok=   4,
   kXR_hasipv64=   8,
   kXR_onlyprv4=  16,
   kXR_onlyprv6=  32
};

// this is a bitmask
enum XLoginCapVer {
   kXR_lcvnone = 0,
   kXR_vermask = 63,
   kXR_asyncap = 128
};

// this is a single number that goes into capver as the version
//
enum XLoginVersion {
   kXR_ver000 = 0,  // Old clients predating history
   kXR_ver001 = 1,  // Generally implemented 2005 protocol
   kXR_ver002 = 2,  // Same as 1 but adds asyncresp recognition
   kXR_ver003 = 3,  // The 2011-2012 rewritten client
   kXR_ver004 = 4   // The 2016 sign-capable   client
};

enum XStatRequestOption {
   kXR_vfs    = 1
};

enum XStatRespFlags {
   kXR_file    = 0,
   kXR_xset    = 1,
   kXR_isDir   = 2,
   kXR_other   = 4,
   kXR_offline = 8,
   kXR_readable=16,
   kXR_writable=32,
   kXR_poscpend=64,
   kXR_bkpexist=128
};

enum XDirlistRequestOption {
   kXR_online = 1,
   kXR_dstat  = 2
};

enum XOpenRequestOption {
   kXR_compress = 1,      // also locate (return unique hosts)
   kXR_delete   = 2,
   kXR_force    = 4,
   kXR_new      = 8,
   kXR_open_read= 16,
   kXR_open_updt= 32,
   kXR_async    = 64,
   kXR_refresh  = 128,   // also locate
   kXR_mkpath   = 256,
   kXR_prefname = 256,   // only locate
   kXR_open_apnd= 512,
   kXR_retstat  = 1024,
   kXR_replica  = 2048,
   kXR_posc     = 4096,
   kXR_nowait   = 8192,  // also locate
   kXR_seqio    =16384,
   kXR_open_wrto=32768
};

enum XProtocolRequestFlags {
   kXR_secreqs  = 1      // Return security requirements
};

enum XQueryType {
   kXR_QStats = 1,
   kXR_QPrep  = 2,
   kXR_Qcksum = 3,
   kXR_Qxattr = 4,
   kXR_Qspace = 5,
   kXR_Qckscan= 6,
   kXR_Qconfig= 7,
   kXR_Qvisa  = 8,
   kXR_Qopaque=16,
   kXR_Qopaquf=32,
   kXR_Qopaqug=64
};

enum XVerifyType {
   kXR_nocrc  = 0,
   kXR_crc32  = 1
};

enum XLogonType {
   kXR_useruser  = 0,
   kXR_useradmin = 1
};

enum XPrepRequestOption {
   kXR_cancel = 1,
   kXR_notify = 2,
   kXR_noerrs = 4,
   kXR_stage  = 8,
   kXR_wmode  = 16,
   kXR_coloc  = 32,
   kXR_fresh  = 64
};

// Version used for kXR_decrypt and kXR_sigver and is set in
// Set in SigverRequest::version, DecryptRequest::version and
// ServerResponseReqs_Protocol::secver
#define kXR_secver_0  0

// Flags for kXR_decrypt and kXR_sigver
enum XSecFlags {
   kXR_nodata   = 1  // Request payload was not hashed or encrypted
};

// Cryptography used for kXR_sigver SigverRequest::crypto
enum XSecCrypto {
   kXR_SHA256   = 0x01,   // Hash used
   kXR_HashMask = 0x0f,   // Mak to extract the hash type
   kXR_rsaKey   = 0x80    // The rsa key was used
};

// kXR_fattr subcodes
//
enum xfaSubCode {
   kXR_fattrDel    = 0,
   kXR_fattrGet    = 1,
   kXR_fattrList   = 2,
   kXR_fattrSet    = 3,
   kXR_fatrrMaxSC  = 3  // Highest valid subcode
};

// kXR_fattr limits
//
enum xfaLimits {
   kXR_faMaxVars = 16,
   kXR_faMaxNlen = 248,
   kXR_faMaxVlen = 65536
};

//_______________________________________________
// PROTOCOL DEFINITION: SERVER'S RESPONSES TYPES
//_______________________________________________
//
enum XResponseType {
   kXR_ok      = 0,
   kXR_oksofar = 4000,
   kXR_attn,
   kXR_authmore,
   kXR_error,
   kXR_redirect,
   kXR_wait,
   kXR_waitresp,
   kXR_noResponsesYet = 10000
};

//_______________________________________________
// PROTOCOL DEFINITION: SERVER"S ATTN CODES
//_______________________________________________

enum XActionCode {
   kXR_asyncab =     5000,
   kXR_asyncdi,   // 5001
   kXR_asyncms,   // 5002
   kXR_asyncrd,   // 5003
   kXR_asyncwt,   // 5004
   kXR_asyncav,   // 5005
   kXR_asynunav,  // 5006
   kXR_asyncgo,   // 5007
   kXR_asynresp   // 5008
};

//_______________________________________________
// PROTOCOL DEFINITION: SERVER'S ERROR CODES
//_______________________________________________
//
enum XErrorCode {
   kXR_ArgInvalid =        3000,
   kXR_ArgMissing,      // 3001
   kXR_ArgTooLong,      // 3002
   kXR_FileLocked,      // 3003
   kXR_FileNotOpen,     // 3004
   kXR_FSError,         // 3005
   kXR_InvalidRequest,  // 3006
   kXR_IOError,         // 3007
   kXR_NoMemory,        // 3008
   kXR_NoSpace,         // 3009
   kXR_NotAuthorized,   // 3010
   kXR_NotFound,        // 3011
   kXR_ServerError,     // 3012
   kXR_Unsupported,     // 3013
   kXR_noserver,        // 3014
   kXR_NotFile,         // 3015
   kXR_isDirectory,     // 3016
   kXR_Cancelled,       // 3017
   kXR_ChkLenErr,       // 3018
   kXR_ChkSumErr,       // 3019
   kXR_inProgress,      // 3020
   kXR_overQuota,       // 3021
   kXR_SigVerErr,       // 3022
   kXR_DecryptErr,      // 3023
   kXR_Overloaded,      // 3024
   kXR_fsReadOnly,      // 3025
   kXR_BadPayload,      // 3026
   kXR_AttrNotFound,    // 3027
   kXR_ERRFENCE,    // Always last valid errcode + 1
   kXR_noErrorYet = 10000
};


//______________________________________________
// PROTOCOL DEFINITION: CLIENT'S REQUESTS STRUCTS
//______________________________________________
// 
// We need to pack structures sent all over the net!
// __attribute__((packed)) assures no padding bytes.
//
// Nice bodies of the headers for the client requests.
// Note that the protocol specifies these values to be in network
//  byte order when sent
//
// G.Ganis: use of flat structures to avoid packing options

struct ClientAdminRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char reserved[16];
   kXR_int32  dlen;
};
struct ClientAuthRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char reserved[12];
   kXR_char credtype[4];
   kXR_int32  dlen;
};
struct ClientBindRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char  sessid[16];
   kXR_int32  dlen;
};
struct ClientChmodRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char  reserved[14];
   kXR_unt16 mode;
   kXR_int32  dlen;
};
struct ClientCloseRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char fhandle[4];
   kXR_int64 fsize;
   kXR_char reserved[4];
   kXR_int32  dlen;
};
struct ClientDecryptRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_unt16 expectrid; // Request code of subsequent request
   kXR_char  version;   // Security version being used (see enum XSecVersion)
   kXR_char  flags;     // One or more flags defined in enum XSecFlags
   kXR_char  reserved[12];
   kXR_int32 dlen;
};
struct ClientDirlistRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char reserved[15];
   kXR_char options[1];
   kXR_int32  dlen;
};
struct ClientEndsessRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char  sessid[16];
   kXR_int32  dlen;
};
struct ClientFattrRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char  fhandle[4];
   kXR_char  subcode;
   kXR_char  numattr;
   kXR_char  options;
   kXR_char  reserved[9];
   kXR_int32 dlen;

// Valid options:
//
   static const int isNew = 0x01; // For set,  the variable must not exist
   static const int aData = 0x10; // For list, return attribute value
};
struct ClientGetfileRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_int32 options;
   kXR_char reserved[8];
   kXR_int32 buffsz;
   kXR_int32  dlen;
};
struct ClientLocateRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_unt16 options;
   kXR_char reserved[14];
   kXR_int32  dlen;
};
struct ClientLoginRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_int32 pid;
   kXR_char username[8];
   kXR_char reserved;
   kXR_char ability;       // See XLoginAbility enum flags
   kXR_char capver[1];     // See XLoginCapVer  enum flags
   kXR_char role[1];
   kXR_int32  dlen;
};
struct ClientMkdirRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char options[1];
   kXR_char reserved[13];
   kXR_unt16 mode;
   kXR_int32  dlen;
};
struct ClientMvRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char reserved[14];
   kXR_int16  arg1len;
   kXR_int32  dlen;
};
struct ClientOpenRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_unt16 mode;
   kXR_unt16 options;
   kXR_char  reserved[12];
   kXR_int32  dlen;
};

struct ClientPingRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char reserved[16];
   kXR_int32  dlen;
};
struct ClientProtocolRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_int32 clientpv;      // 2.9.7 or higher
   kXR_char  flags;         // 3.1.0 or higher
   kXR_char  reserved[11];
   kXR_int32 dlen;
};
struct ClientPrepareRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char  options;
   kXR_char  prty;
   kXR_unt16 port;          // 2.9.9 or higher
   kXR_char  reserved[12];
   kXR_int32 dlen;
};
struct ClientPutfileRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_int32 options;
   kXR_char  reserved[8];
   kXR_int32 buffsz;
   kXR_int32  dlen;
};
struct ClientQueryRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_unt16 infotype;
   kXR_char  reserved1[2];
   kXR_char  fhandle[4];
   kXR_char  reserved2[8];
   kXR_int32 dlen;
};
struct ClientReadRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char fhandle[4];
   kXR_int64 offset;
   kXR_int32 rlen;
   kXR_int32  dlen;
};
struct ClientReadVRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char  reserved[15];
   kXR_char  pathid;
   kXR_int32 dlen;
};
struct ClientRmRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char reserved[16];
   kXR_int32  dlen;
};
struct ClientRmdirRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char reserved[16];
   kXR_int32  dlen;
};
struct ClientSetRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char reserved[15];
   kXR_char  modifier;  // For security purposes, should be zero
   kXR_int32  dlen;
};
struct ClientSigverRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_unt16 expectrid; // Request code of subsequent request
   kXR_char  version;   // Security version being used (see XSecVersion)
   kXR_char  flags;     // One or more flags defined in enum (see XSecFlags)
   kXR_unt64 seqno;     // Monotonically increasing number (part of hash)
   kXR_char  crypto;    // Cryptography used (see XSecCrypto)
   kXR_char  rsvd2[3];
   kXR_int32 dlen;
};
struct ClientStatRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char  options;
   kXR_char reserved[11];
   kXR_char fhandle[4];
   kXR_int32  dlen;
};
struct ClientSyncRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char fhandle[4];
   kXR_char reserved[12];
   kXR_int32  dlen;
};
struct ClientTruncateRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char fhandle[4];
   kXR_int64 offset;
   kXR_char reserved[4];
   kXR_int32  dlen;
};
struct ClientWriteRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char fhandle[4];
   kXR_int64 offset;
   kXR_char  pathid;
   kXR_char reserved[3];
   kXR_int32  dlen;
};
struct ClientWriteVRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char  options;  // See static const ints below
   kXR_char  reserved[15];
   kXR_int32 dlen;

   static const kXR_int32 doSync = 0x01;
};
struct ClientVerifywRequest {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char  fhandle[4];
   kXR_int64 offset;
   kXR_char  pathid;
   kXR_char  vertype;       // One of XVerifyType
   kXR_char  reserved[2];
   kXR_int32 dlen;          // Includes crc length
};

struct ClientRequestHdr {
   kXR_char  streamid[2];
   kXR_unt16 requestid;
   kXR_char  body[16];
   kXR_int32  dlen;
};

typedef union {
   struct ClientRequestHdr header;
   struct ClientAdminRequest admin;
   struct ClientAuthRequest auth;
   struct ClientBindRequest bind;
   struct ClientChmodRequest chmod;
   struct ClientCloseRequest close;
   struct ClientDecryptRequest decrypt;
   struct ClientDirlistRequest dirlist;
   struct ClientEndsessRequest endsess;
   struct ClientFattrRequest fattr;
   struct ClientGetfileRequest getfile;
   struct ClientLocateRequest locate;
   struct ClientLoginRequest login;
   struct ClientMkdirRequest mkdir;
   struct ClientMvRequest mv;
   struct ClientOpenRequest open;
   struct ClientPingRequest ping;
   struct ClientPrepareRequest prepare;
   struct ClientProtocolRequest protocol;
   struct ClientPutfileRequest putfile;
   struct ClientQueryRequest query;
   struct ClientReadRequest read;
   struct ClientReadVRequest readv;
   struct ClientRmRequest rm;
   struct ClientRmdirRequest rmdir;
   struct ClientSetRequest set;
   struct ClientSigverRequest sigver;
   struct ClientStatRequest stat;
   struct ClientSyncRequest sync;
   struct ClientTruncateRequest truncate;
   struct ClientWriteRequest write;
   struct ClientWriteVRequest writev;
} ClientRequest;

typedef union {
   struct ClientRequestHdr header;
   struct ClientDecryptRequest decrypt;
   struct ClientSigverRequest sigver;
} SecurityRequest;

struct readahead_list {
   kXR_char fhandle[4];
   kXR_int32 rlen;
   kXR_int64 offset;
};

struct read_args {
   kXR_char       pathid;
   kXR_char       reserved[7];
   // his struct is followed by an array of readahead_list
};

// New additions are placed in a specia namespace to avoid conflicts
//
namespace XrdProto
{
struct read_list {
   kXR_char fhandle[4];
   kXR_int32 rlen;
   kXR_int64 offset;
};

struct write_list {
   kXR_char fhandle[4];
   kXR_int32 wlen;
   kXR_int64 offset;
};
}

//_____________________________________________________________________
//   PROTOCOL DEFINITION: SERVER'S RESPONSE
//_____________________________________________________________________
//

// Nice header for the server response.
// Note that the protocol specifies these values to be in network
// byte order when sent
//
// G.Ganis: The following structures never need padding bytes:
//          no need of packing options

struct ServerResponseHeader {
   kXR_char streamid[2];
   kXR_unt16 status;
   kXR_int32  dlen;
};

// Body for the kXR_bind response... useful
struct ServerResponseBody_Bind {
    kXR_char substreamid;
};

// Body for the kXR_open response... useful
struct ServerResponseBody_Open {
   kXR_char fhandle[4];
   kXR_int32 cpsize;   // cpsize & cptype returned if kXR_compress *or*
   kXR_char cptype[4]; // kXR_retstat is specified
}; // info will follow if kXR_retstat is specified

// The following information is returned in the response body when kXR_secreqs
// is set in ClientProtocolRequest::flags. Note that the size of secvec is
// defined by secvsz and will not be present when secvsz == 0.
struct ServerResponseSVec_Protocol {
   kXR_char  reqindx;     // Request index
   kXR_char  reqsreq;     // Request signing requirement
};

struct ServerResponseReqs_Protocol {
   kXR_char  theTag;      // Always the character 'S' to identify struct
   kXR_char  rsvd;        // Reserved for the future (always 0 for now)
   kXR_char  secver;      // Security version
   kXR_char  secopt;      // Security options
   kXR_char  seclvl;      // Security level when secvsz == 0
   kXR_char  secvsz;      // Number of items in secvec (i.e. its length/2)
   ServerResponseSVec_Protocol secvec;
};

// Options reflected in protocol response ServerResponseReqs_Protocol::secopt
//
#define kXR_secOData 0x01
#define kXR_secOFrce 0x02

// Security level definitions (these are predefined but can be over-ridden)
//
#define kXR_secNone       0
#define kXR_secCompatible 1
#define kXR_secStandard   2
#define kXR_secIntense    3
#define kXR_secPedantic   4

// Requirements one of which set in each ServerResponseReqs_Protocol::secvec
//
#define kXR_signIgnore    0
#define kXR_signLikely    1
#define kXR_signNeeded    2

// Body for the kXR_protocol response... useful
struct ServerResponseBody_Protocol {
   kXR_int32 pval;
   kXR_int32 flags;
   ServerResponseReqs_Protocol secreq; // Only for V3.1.0+ && if requested
};

// Handy definition of the size of the protocol response when the security
// information is not present.
//
#define kXR_ShortProtRespLen sizeof(ServerResponseBody_Protocol)-\
                             sizeof(ServerResponseReqs_Protocol)

struct ServerResponseBody_Login {
   kXR_char  sessid[16];
   kXR_char  sec[4096]; // Should be sufficient for every use
};

struct ServerResponseBody_Redirect {
   kXR_int32 port;
   char host[4096]; // Should be sufficient for every use
};

struct ServerResponseBody_Error {
   kXR_int32 errnum;
   char errmsg[4096]; // Should be sufficient for every use
};

struct ServerResponseBody_Wait {
   kXR_int32 seconds;
   char infomsg[4096]; // Should be sufficient for every use
};

struct ServerResponseBody_Waitresp {
   kXR_int32 seconds;
};

struct ServerResponseBody_Attn {
   kXR_int32 actnum;
   char parms[4096]; // Should be sufficient for every use
};

struct ServerResponseBody_Attn_asyncrd {
   kXR_int32 actnum;
   kXR_int32 port;
   char host[4092];
};

struct ServerResponseBody_Attn_asynresp {
   kXR_int32            actnum;
   char reserved[4];
   ServerResponseHeader resphdr;
   char respdata[4096];
};

struct ServerResponseBody_Attn_asyncwt {
   kXR_int32 actnum;
   kXR_int32 wsec;
};

struct ServerResponseBody_Attn_asyncdi {
   kXR_int32 actnum;
   kXR_int32 wsec;
   kXR_int32 msec;
};

struct ServerResponseBody_Authmore {
   char data[4096];
};

struct ServerResponseBody_Buffer {
   char data[4096];
};

struct ServerResponse
{
  ServerResponseHeader hdr;
  union
  {
    ServerResponseBody_Error    error;
    ServerResponseBody_Authmore authmore;
    ServerResponseBody_Wait     wait;
    ServerResponseBody_Waitresp waitresp;
    ServerResponseBody_Redirect redirect;
    ServerResponseBody_Attn     attn;
    ServerResponseBody_Protocol protocol;
    ServerResponseBody_Login    login;
    ServerResponseBody_Buffer   buffer;
    ServerResponseBody_Bind     bind;
  } body;
};

void ServerResponseHeader2NetFmt(struct ServerResponseHeader *srh);

// The fields to be sent as initial handshake
struct ClientInitHandShake {
   kXR_int32 first;
   kXR_int32 second;
   kXR_int32 third;
   kXR_int32 fourth;
   kXR_int32 fifth;
};

// The body received after the first handshake's header
struct ServerInitHandShake {
   kXR_int32 msglen;
   kXR_int32 protover;
   kXR_int32 msgval;
};



typedef kXR_int32 ServerResponseType;

struct ALIGN_CHECK {char chkszreq[25-sizeof(ClientRequest)];
   char chkszrsp[ 9-sizeof(ServerResponseHeader)];
};

/******************************************************************************/
/*                   X P r o t o c o l   U t i l i t i e s                    */
/******************************************************************************/

#include <errno.h>
#if defined(WIN32)
#if !defined(ENOTBLK)
#  define ENOTBLK 15
#endif
#if !defined(ETXTBSY)
#define ETXTBSY 26
#endif
#if !defined(ENOBUFS)
#define ENOBUFS 105
#endif
#if !defined(ENETUNREACH)
#define ENETUNREACH 114
#endif
#endif

#ifndef ENOATTR
#define ENOATTR ENODATA
#endif
  
class XProtocol
{
public:

// mapError() is the occicial mapping from errno to xrootd protocol error.
//
static int mapError(int rc)
      {if (rc < 0) rc = -rc;
       switch(rc)
          {case ENOENT:       return kXR_NotFound;
           case EINVAL:       return kXR_ArgInvalid;
           case EPERM:        return kXR_NotAuthorized;
           case EACCES:       return kXR_NotAuthorized;
           case EIO:          return kXR_IOError;
           case ENOMEM:       return kXR_NoMemory;
           case ENOBUFS:      return kXR_NoMemory;
           case ENOSPC:       return kXR_NoSpace;
           case ENAMETOOLONG: return kXR_ArgTooLong;
           case ENETUNREACH:  return kXR_noserver;
           case ENOTBLK:      return kXR_NotFile;
           case EISDIR:       return kXR_isDirectory;
           case EEXIST:       return kXR_InvalidRequest;
           case ETXTBSY:      return kXR_inProgress;
           case ENODEV:       return kXR_FSError;
           case EFAULT:       return kXR_ServerError;
           case EDOM:         return kXR_ChkSumErr;
           case EDQUOT:       return kXR_overQuota;
           case EILSEQ:       return kXR_SigVerErr;
           case ERANGE:       return kXR_DecryptErr;
           case EUSERS:       return kXR_Overloaded;
           case EROFS:        return kXR_fsReadOnly;
           case ENOATTR:      return kXR_AttrNotFound;
           default:           return kXR_FSError;
          }
      }

static int toErrno( int xerr )
{
    switch(xerr)
       {case kXR_ArgInvalid:    return EINVAL;
        case kXR_ArgMissing:    return EINVAL;
        case kXR_ArgTooLong:    return ENAMETOOLONG;
        case kXR_FileLocked:    return EDEADLK;
        case kXR_FileNotOpen:   return EBADF;
        case kXR_FSError:       return EIO;
        case kXR_InvalidRequest:return EEXIST;
        case kXR_IOError:       return EIO;
        case kXR_NoMemory:      return ENOMEM;
        case kXR_NoSpace:       return ENOSPC;
        case kXR_NotAuthorized: return EACCES;
        case kXR_NotFound:      return ENOENT;
        case kXR_ServerError:   return ENOMSG;
        case kXR_Unsupported:   return ENOSYS;
        case kXR_noserver:      return EHOSTUNREACH;
        case kXR_NotFile:       return ENOTBLK;
        case kXR_isDirectory:   return EISDIR;
        case kXR_Cancelled:     return ECANCELED;
        case kXR_ChkLenErr:     return EDOM;
        case kXR_ChkSumErr:     return EDOM;
        case kXR_inProgress:    return EINPROGRESS;
        case kXR_overQuota:     return EDQUOT;
        case kXR_SigVerErr:     return EILSEQ;
        case kXR_DecryptErr:    return ERANGE;
        case kXR_Overloaded:    return EUSERS;
        case kXR_fsReadOnly:    return EROFS;
        case kXR_BadPayload:    return EINVAL;
        case kXR_AttrNotFound:  return ENOATTR;
        default:                return ENOMSG;
       }
}

static const char *errName(kXR_int32 errCode);

static const char *reqName(kXR_unt16 reqCode);
};
#endif