/*-
 * Copyright (c) 2005-2008 Daniel Braniss <danny@cs.huji.ac.il>
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 *
 * $FreeBSD: src/sys/dev/iscsi/initiator/iscsi.h,v 1.2 2008/11/25 07:17:11 scottl Exp $
 */
/*
 | $Id: iscsi.h,v 1.17 2006/12/01 09:10:17 danny Exp danny $
 */
#ifndef _KERNEL
#include <stdbool.h>
#else
#include <sys/stdint.h>
#endif

#include <sys/objcache.h>
#include <bus/cam/cam.h>
#include <sys/device.h>

#define ISCSIDEV        "iscsi"

#define ISCSI_MAX_TARGETS       4 //64

#define ISCSI_MAX_LUNS          4

/*
 | iSCSI commands
 */

/*
 | Initiator Opcodes:
 */
#define ISCSI_NOP_OUT           0x00
#define ISCSI_SCSI_CMD          0x01
#define ISCSI_TASK_CMD          0x02
#define ISCSI_LOGIN_CMD         0x03
#define ISCSI_TEXT_CMD          0x04
#define ISCSI_WRITE_DATA        0x05
#define ISCSI_LOGOUT_CMD        0x06
#define ISCSI_SNACK             0x10
/*
 | Target Opcodes:
 */
#define ISCSI_NOP_IN            0x20
#define ISCSI_SCSI_RSP          0x21
#define ISCSI_TASK_RSP          0x22
#define ISCSI_LOGIN_RSP         0x23
#define ISCSI_TEXT_RSP          0x24
#define ISCSI_READ_DATA         0x25
#define ISCSI_LOGOUT_RSP        0x26
#define ISCSI_R2T               0x31
#define ISCSI_ASYNC             0x32
#define ISCSI_REJECT            0x3f
/*
 | PDU stuff
 */
/*
 | BHS Basic Header Segment
 */
typedef struct bhs {
     // the order is network byte order!
     u_char     opcode:6;
     u_char     I:1;
     u_char     _:1;
     u_char     __:7;
     u_char     F:1;                    // Final bit
     u_char     ___[2];

     u_int      AHSLength:8;            // in 4byte words
     u_int      DSLength:24;            // in bytes

     u_int      LUN[2];                 // or Opcode-specific fields
     u_int      itt;
     u_int      OpcodeSpecificFields[7];
#define CmdSN           OpcodeSpecificFields[1]
#define ExpStSN         OpcodeSpecificFields[2]
#define MaxCmdSN        OpcodeSpecificFields[3]
} bhs_t;

typedef struct ahs {
     u_int      len:16;
     u_int      type:8;
     u_int      spec:8;
     char       data[0];
} ahs_t;

typedef struct {
     // Sequence Numbers
     // (computers were invented to count, right?)
     int        cmd;
     int        expcmd;
     int        maxcmd;
} req_sn_t;

typedef struct {
     // Sequence Numbers
     // (computers were invented to count, right?)
     int        stat;
     int        expcmd;
     int        maxcmd;
} rsp_sn_t;

typedef struct scsi_req {
     u_char     opcode:6; // 0x01
     u_char     I:1;
     u_char     _:1;

     u_char     attr:3;
     u_char     _0:2;
     u_char     W:1;
     u_char     R:1;
     u_char     F:1;
#define         iSCSI_TASK_UNTAGGED     0
#define         iSCSI_TASK_SIMPLE       1
#define         iSCSI_TASK_ORDER        2
#define         iSCSI_TASK_HOFQ         3
#define         iSCSI_TASK_ACA          4
     char       _1[2];
     int        len;
     int        lun[2];
     int        itt;
     int        edtlen;         // expectect data transfere length
     int        cmdSN;
     int        extStatSN;
     int        cdb[4];
} scsi_req_t;

typedef struct scsi_rsp {
     char       opcode; // 0x21
     u_char     flag;
     u_char     response;
     u_char     status;

     int        len;
     int        _[2];
     int        itt;
     int        stag;
     rsp_sn_t   sn;
     int        expdatasn;
     int        bdrcnt; // bidirectional residual count
     int        rcnt;   // residual count
} scsi_rsp_t;

typedef struct nop_out {
     // the order is network byte order!
     u_char     opcode:6;
     u_char     I:1;
     u_char     _:1;
     u_char     __:7;
     u_char     F:1;                    // Final bit
     u_char     ___[2];

     u_int      len;
     u_int      lun[2];
     u_int      itt;
     u_int      ttt;
     req_sn_t   sn;
     u_int      mbz[3];
} nop_out_t;

typedef struct nop_in {
     // the order is network byte order!
     u_char     opcode:6;
     u_char     I:1;
     u_char     _:1;
     u_char     __:7;
     u_char     F:1;                    // Final bit
     u_char     ___[2];

     u_int      len;
     u_int      lun[2];
     u_int      itt;
     u_int      ttt;
     rsp_sn_t   sn;
     u_int      ____[2];

} nop_in_t;

typedef struct r2t {
     u_char     opcode:6;
     u_char     I:1;
     u_char     _:1;
     u_char     __:7;
     u_char     F:1;                    // Final bit
     u_char     ___[2];

     u_int      len;
     u_int      lun[2];
     u_int      itt;
     u_int      ttt;
     rsp_sn_t   sn;
     u_int      r2tSN;
     u_int      bo;
     u_int      ddtl;
} r2t_t;

typedef struct data_out {
     u_char     opcode:6;
     u_char     I:1;
     u_char     _:1;
     u_char     __:7;
     u_char     F:1;                    // Final bit
     u_char     ___[2];

     u_int      len;
     u_int      lun[2];
     u_int      itt;
     u_int      ttt;
     rsp_sn_t   sn;
     u_int      dsn;    // data seq. number
     u_int      bo;
     u_int      ____;
} data_out_t;

typedef struct data_in {
     u_char     opcode:6;
     u_char     I:1;
     u_char     _:1;

     u_char     S:1;
     u_char     U:1;
     u_char     O:1;
     u_char     __:3;
     u_char     A:1;
     u_char     F:1;                    // Final bit
     u_char     ___[1];
     u_char     status;

     u_int      len;
     u_int      lun[2];
     u_int      itt;
     u_int      ttt;
     rsp_sn_t   sn;
     u_int      dataSN;
     u_int      bo;
     u_int      ____;
} data_in_t;

typedef struct reject {
     u_char     opcode:6;
     u_char     _:2;
     u_char     F:1;
     u_char     __:7;
     u_char     reason;
     u_char     ___;

     u_int      len;
     u_int      ____[2];
     u_int      tt[2];  // must be -1
     rsp_sn_t   sn;
     u_int      dataSN; // or R2TSN or reserved
     u_int      _____[2];
} reject_t;

typedef struct async {
     u_char     opcode:6;
     u_char     _:2;
     u_char     F:1;
     u_char     __:7;
     u_char     ___[2];

     u_int      len;
     u_int      lun[2];
     u_int      itt;    // must be -1
     u_int      ____;
     rsp_sn_t   sn;

     u_char     asyncEvent;
     u_char     asyncVCode;
     u_char     param1[2];
     u_char     param2[2];
     u_char     param3[2];

     u_int      _____;

} async_t;

typedef struct login_req {
     char       cmd;    // 0x03

     u_char     NSG:2;
     u_char     CSG:2;
     u_char     _:2;
     u_char     C:1;
     u_char     T:1;

     char       v_max;
     char       v_min;

     int        len;    // remapped via standard bhs
     char       isid[6];
     short      tsih;
     int        itt;    // Initiator Task Tag;

     int        CID:16;
     int        rsv:16;

     int        cmdSN;
     int        expStatSN;
     int        unused[4];
} login_req_t;

typedef struct login_rsp {
     char       cmd;    // 0x23
     u_char     NSG:2;
     u_char     CSG:2;
     u_char     _1:2;
     u_char     C:1;
     u_char     T:1;

     char       v_max;
     char       v_act;

     int        len;    // remapped via standard bhs
     char       isid[6];
     short      tsih;
     int        itt;    // Initiator Task Tag;
     int        _2;
     rsp_sn_t   sn;
     int        status:16;
     int        _3:16;
     int        _4[2];
} login_rsp_t;

typedef struct text_req {
     char       cmd;    // 0x04

     u_char     _1:6;
     u_char     C:1;    // Continuation
     u_char     F:1;    // Final
     char       _2[2];

     int        len;
     int        itt;            // Initiator Task Tag
     int        LUN[2];
     int        ttt;            // Target Transfer Tag
     int        cmdSN;
     int        expStatSN;
     int        unused[4];
} text_req_t;

typedef struct logout_req {
     char       cmd;    // 0x06
     char       reason; // 0 - close session
                        // 1 - close connection
                        // 2 - remove the connection for recovery
     char       _2[2];

     int        len;
     int        _r[2];
     int        itt;    // Initiator Task Tag;

     u_int      CID:16;
     u_int      rsv:16;

     int        cmdSN;
     int        expStatSN;
     int        unused[4];
} logout_req_t;

typedef struct logout_rsp {
     char       cmd;    // 0x26
     char       cbits;
     char       _1[2];
     int        len;
     int        _2[2];
     int        itt;
     int        _3;
     rsp_sn_t   sn;
     short      time2wait;
     short      time2retain;
     int        _4;
} logout_rsp_t;

union ipdu_u {
     bhs_t      bhs;
     scsi_req_t scsi_req;
     scsi_rsp_t scsi_rsp;
     nop_out_t  nop_out;
     nop_in_t   nop_in;
     r2t_t      r2t;
     data_out_t data_out;
     data_in_t  data_in;
     reject_t   reject;
     async_t    async;
};

/*
 | Sequence Numbers
 */
typedef struct {
     u_int      itt;
     u_int      cmd;
     u_int      expCmd;
     u_int      maxCmd;
     u_int      stat;
     u_int      expStat;
     u_int      data;
} sn_t;

/*
 | in-core version of a Protocol Data Unit
 */
typedef struct {
     union ipdu_u       ipdu;

     ahs_t              *ahs;
     u_int              ahs_len;
     u_int              ahs_size;       // the allocated size
     u_int              hdr_dig;        // header digest

     u_char             *ds;
     u_int              ds_len;
     u_int              ds_size;        // the allocated size
     u_int              ds_dig;         // data digest
} pdu_t;

typedef struct opvals {
     int        port;
     int        tags;
     int        maxluns;
     int        sockbufsize;

     int        maxConnections;
     int        maxRecvDataSegmentLength;
     int        maxXmitDataSegmentLength; // pseudo ...
     int        maxBurstLength;
     int        firstBurstLength;
     int        defaultTime2Wait;
     int        defaultTime2Retain;
     int        maxOutstandingR2T;
     int        errorRecoveryLevel;
     int        targetPortalGroupTag;

     bool       initialR2T;
     bool       immediateData;
     bool       dataPDUInOrder;
     bool       dataSequenceInOrder;
     char       *headerDigest;
     char       *dataDigest;
     char       *sessionType;
     char       *sendTargets;
     char       *targetAddress;
     char       *targetAlias;
     char       *targetName;
     char       *initiatorName;
     char       *initiatorAlias;
     char       *authMethod;
     char       *chapSecret;
     char       *chapIName;
     char       *chapDigest;
     char       *tgtChapName;
     char       *tgtChapSecret;
     int        tgtChallengeLen;
     u_char     tgtChapID;
     char       *tgtChapDigest;
     char       *iqn;
} isc_opt_t;

/*
 | ioctl
 */
#define ISCSISETSES     _IOR('i', 1, int)
#define ISCSISETSOC     _IOW('i', 2, int)
#define ISCSISETOPT     _IOW('i', 5, isc_opt_t)
#define ISCSIGETOPT     _IOR('i', 6, isc_opt_t)

#define ISCSISEND       _IOW('i', 10, pdu_t)
#define ISCSIRECV       _IOWR('i', 11, pdu_t)

#define ISCSIPING       _IO('i', 20)
#define ISCSISIGNAL     _IOW('i', 21, int *)

#define ISCSISTART      _IO('i', 30)
#define ISCSIRESTART    _IO('i', 31)
#define ISCSISTOP       _IO('i', 32)

typedef struct iscsi_cam {
     path_id_t          path_id;
     target_id_t        target_id;
     int                target_nluns;
     lun_id_t           target_lun[ISCSI_MAX_LUNS];
} iscsi_cam_t;

#define ISCSIGETCAM     _IOR('i', 33, iscsi_cam_t)