Files
gotgt/pkg/port/iscsit/cmd.go
2019-11-18 15:16:41 +05:30

511 lines
13 KiB
Go

/*
Copyright 2017 The GoStor Authors All rights reserved.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package iscsit
import (
"bytes"
"fmt"
"strings"
"time"
"github.com/gostor/gotgt/pkg/api"
"github.com/gostor/gotgt/pkg/util"
log "github.com/sirupsen/logrus"
)
type OpCode int
const (
// Defined on the initiator.
OpNoopOut OpCode = 0x00
OpSCSICmd = 0x01
OpSCSITaskReq = 0x02
OpLoginReq = 0x03
OpTextReq = 0x04
OpSCSIOut = 0x05
OpLogoutReq = 0x06
OpSNACKReq = 0x10
// Defined on the target.
OpNoopIn OpCode = 0x20
OpSCSIResp = 0x21
OpSCSITaskResp = 0x22
OpLoginResp = 0x23
OpTextResp = 0x24
OpSCSIIn = 0x25
OpLogoutResp = 0x26
OpReady = 0x31
OpAsync = 0x32
OpReject = 0x3f
)
const (
MaxBurstLength uint32 = 262144
MaxRecvDataSegmentLength uint32 = 65536
)
var opCodeMap = map[OpCode]string{
OpNoopOut: "NOP-Out",
OpSCSICmd: "SCSI Command",
OpSCSITaskReq: "SCSI Task Management FunctionRequest",
OpLoginReq: "Login Request",
OpTextReq: "Text Request",
OpSCSIOut: "SCSI Data-Out (write)",
OpLogoutReq: "Logout Request",
OpSNACKReq: "SNACK Request",
OpNoopIn: "NOP-In",
OpSCSIResp: "SCSI Response",
OpSCSITaskResp: "SCSI Task Management Function Response",
OpLoginResp: "Login Response",
OpTextResp: "Text Response",
OpSCSIIn: "SCSI Data-In (read)",
OpLogoutResp: "Logout Response",
OpReady: "Ready To Transfer (R2T)",
OpAsync: "Asynchronous Message",
OpReject: "Reject",
}
const DataPadding = 4
type ISCSITaskManagementFunc struct {
Result byte
TaskFunc uint32
ReferencedTaskTag uint32
}
type ISCSICommand struct {
OpCode OpCode
RawHeader []byte
DataLen int
RawData []byte
Final bool
FinalInSeq bool
Immediate bool
TaskTag uint32
StartTime time.Time
ExpCmdSN, MaxCmdSN uint32
AHSLen int
Resid uint32
// Connection ID.
ConnID uint16
// Command serial number.
CmdSN uint32
// Expected status serial.
ExpStatSN uint32
Read, Write bool
LUN [8]uint8
// Transit bit.
Transit bool
// Continue bit.
Cont bool
// Current Stage, Next Stage.
CSG, NSG iSCSILoginStage
// Initiator part of the SSID.
ISID uint64
// Target-assigned Session Identifying Handle.
TSIH uint16
// Status serial number.
StatSN uint32
// For login response.
StatusClass uint8
StatusDetail uint8
// SCSI commands
SCSIOpCode byte
ExpectedDataLen uint32
CDB []byte
Status byte
SCSIResponse byte
// Task request
ISCSITaskManagementFunc
// R2T
R2TSN uint32
DesiredLength uint32
// Data-In/Out
HasStatus bool
DataSN uint32
BufferOffset uint32
}
func (cmd *ISCSICommand) Bytes() []byte {
switch cmd.OpCode {
case OpLoginResp:
return cmd.loginRespBytes()
case OpLogoutResp:
return cmd.logoutRespBytes()
case OpSCSIResp:
return cmd.scsiCmdRespBytes()
case OpSCSIIn:
return cmd.dataInBytes()
case OpTextResp:
return cmd.textRespBytes()
case OpNoopIn:
return cmd.noopInBytes()
case OpSCSITaskResp:
return cmd.scsiTMFRespBytes()
case OpReady:
return cmd.r2tRespBytes()
}
return nil
}
func (m *ISCSICommand) String() string {
var s []string
s = append(s, fmt.Sprintf("Op: %v", opCodeMap[m.OpCode]))
s = append(s, fmt.Sprintf("Final = %v", m.Final))
s = append(s, fmt.Sprintf("Immediate = %v", m.Immediate))
s = append(s, fmt.Sprintf("Data Segment Length = %d", m.DataLen))
s = append(s, fmt.Sprintf("Task Tag = %x", m.TaskTag))
s = append(s, fmt.Sprintf("AHS Length = %d", m.AHSLen))
switch m.OpCode {
case OpLoginReq:
s = append(s, fmt.Sprintf("ISID = %x", m.ISID))
s = append(s, fmt.Sprintf("Transit = %v", m.Transit))
s = append(s, fmt.Sprintf("Continue = %v", m.Cont))
s = append(s, fmt.Sprintf("Current Stage = %v", m.CSG))
s = append(s, fmt.Sprintf("Next Stage = %v", m.NSG))
case OpLoginResp:
s = append(s, fmt.Sprintf("ISID = %x", m.ISID))
s = append(s, fmt.Sprintf("Transit = %v", m.Transit))
s = append(s, fmt.Sprintf("Continue = %v", m.Cont))
s = append(s, fmt.Sprintf("Current Stage = %v", m.CSG))
s = append(s, fmt.Sprintf("Next Stage = %v", m.NSG))
s = append(s, fmt.Sprintf("Status Class = %d", m.StatusClass))
s = append(s, fmt.Sprintf("Status Detail = %d", m.StatusDetail))
case OpSCSICmd, OpSCSIOut, OpSCSIIn:
s = append(s, fmt.Sprintf("LUN = %d", m.LUN))
s = append(s, fmt.Sprintf("ExpectedDataLen = %d", m.ExpectedDataLen))
s = append(s, fmt.Sprintf("CmdSN = %d", m.CmdSN))
s = append(s, fmt.Sprintf("ExpStatSN = %d", m.ExpStatSN))
s = append(s, fmt.Sprintf("Read = %v", m.Read))
s = append(s, fmt.Sprintf("Write = %v", m.Write))
s = append(s, fmt.Sprintf("CDB = %x", m.CDB))
case OpSCSIResp:
s = append(s, fmt.Sprintf("StatSN = %d", m.StatSN))
s = append(s, fmt.Sprintf("ExpCmdSN = %d", m.ExpCmdSN))
s = append(s, fmt.Sprintf("MaxCmdSN = %d", m.MaxCmdSN))
}
return strings.Join(s, "\n")
}
// parseUint parses the given slice as a network-byte-ordered integer. If
// there are more than 8 bytes in data, it overflows.
func ParseUint(data []byte) uint64 {
var out uint64
for i := 0; i < len(data); i++ {
out += uint64(data[len(data)-i-1]) << uint(8*i)
}
return out
}
func parseHeader(data []byte) (*ISCSICommand, error) {
if len(data) != BHS_SIZE {
return nil, fmt.Errorf("garbled header")
}
// TODO: sync.Pool
m := &ISCSICommand{}
m.Immediate = 0x40&data[0] == 0x40
m.OpCode = OpCode(data[0] & ISCSI_OPCODE_MASK)
m.Final = 0x80&data[1] == 0x80
m.AHSLen = int(data[4]) * 4
m.DataLen = int(ParseUint(data[5:8]))
m.TaskTag = uint32(ParseUint(data[16:20]))
m.StartTime = time.Now()
switch m.OpCode {
case OpSCSICmd:
m.LUN = [8]byte{data[9]}
m.ExpectedDataLen = uint32(ParseUint(data[20:24]))
m.CmdSN = uint32(ParseUint(data[24:28]))
m.Read = data[1]&0x40 == 0x40
m.Write = data[1]&0x20 == 0x20
m.CDB = data[32:48]
m.ExpStatSN = uint32(ParseUint(data[28:32]))
SCSIOpcode := api.SCSICommandType(m.SCSIOpCode)
switch SCSIOpcode {
case api.READ_6, api.READ_10, api.READ_12, api.READ_16:
m.Read = true
case api.WRITE_6, api.WRITE_10, api.WRITE_12, api.WRITE_16, api.WRITE_VERIFY, api.WRITE_VERIFY_12, api.WRITE_VERIFY_16:
m.Write = true
}
fallthrough
case OpSCSITaskReq:
m.ReferencedTaskTag = uint32(ParseUint(data[20:24]))
m.TaskFunc = uint32(data[1] & ISCSI_FLAG_TM_FUNC_MASK)
case OpSCSIResp:
case OpSCSIOut:
m.LUN = [8]byte{data[9]}
m.ExpStatSN = uint32(ParseUint(data[28:32]))
m.DataSN = uint32(ParseUint(data[36:40]))
m.BufferOffset = uint32(ParseUint(data[40:44]))
case OpLoginReq, OpTextReq, OpNoopOut, OpLogoutReq:
m.Transit = m.Final
m.Cont = data[1]&0x40 == 0x40
if m.Cont && m.Transit {
// rfc7143 11.12.2
return nil, fmt.Errorf("transit and continue bits set in same login request")
}
m.CSG = iSCSILoginStage(data[1]&0xc) >> 2
m.NSG = iSCSILoginStage(data[1] & 0x3)
m.ISID = uint64(ParseUint(data[8:14]))
m.TSIH = uint16(ParseUint(data[14:16]))
m.ConnID = uint16(ParseUint(data[20:22]))
m.CmdSN = uint32(ParseUint(data[24:28]))
m.ExpStatSN = uint32(ParseUint(data[28:32]))
case OpLoginResp:
m.Transit = m.Final
m.Cont = data[1]&0x40 == 0x40
if m.Cont && m.Transit {
// rfc7143 11.12.2
return nil, fmt.Errorf("transit and continue bits set in same login request")
}
m.CSG = iSCSILoginStage(data[1]&0xc) >> 2
m.NSG = iSCSILoginStage(data[1] & 0x3)
m.StatSN = uint32(ParseUint(data[24:28]))
m.ExpCmdSN = uint32(ParseUint(data[28:32]))
m.MaxCmdSN = uint32(ParseUint(data[32:36]))
m.StatusClass = uint8(data[36])
m.StatusDetail = uint8(data[37])
}
return m, nil
}
func (m *ISCSICommand) scsiCmdRespBytes() []byte {
// rfc7143 11.4
buf := bytes.Buffer{}
buf.WriteByte(byte(OpSCSIResp))
var flag byte = 0x80
if m.Resid > 0 {
if m.Resid > m.ExpectedDataLen {
flag |= 0x04
} else {
flag |= 0x02
}
}
buf.WriteByte(flag)
buf.WriteByte(byte(m.SCSIResponse))
buf.WriteByte(byte(m.Status))
buf.WriteByte(0x00)
buf.Write(util.MarshalUint64(uint64(len(m.RawData)))[5:]) // 5-8
// Skip through to byte 16
for i := 0; i < 8; i++ {
buf.WriteByte(0x00)
}
buf.Write(util.MarshalUint64(uint64(m.TaskTag))[4:])
for i := 0; i < 4; i++ {
buf.WriteByte(0x00)
}
buf.Write(util.MarshalUint64(uint64(m.StatSN))[4:])
buf.Write(util.MarshalUint64(uint64(m.ExpCmdSN))[4:])
buf.Write(util.MarshalUint64(uint64(m.MaxCmdSN))[4:])
for i := 0; i < 2*4; i++ {
buf.WriteByte(0x00)
}
buf.Write(util.MarshalUint64(uint64(m.Resid))[4:])
buf.Write(m.RawData)
dl := len(m.RawData)
for dl%4 > 0 {
dl++
buf.WriteByte(0x00)
}
return buf.Bytes()
}
func (m *ISCSICommand) dataInBytes() []byte {
// rfc7143 11.7
dl := m.DataLen
for dl%4 > 0 {
dl++
}
var buf = make([]byte, (48 + dl))
buf[0] = byte(OpSCSIIn)
var flag byte
if m.FinalInSeq || m.Final == true {
flag |= 0x80
}
if m.HasStatus && m.Final == true {
flag |= 0x01
}
log.Debugf("resid: %v, ExpectedDataLen: %v", m.Resid, m.ExpectedDataLen)
if m.Resid > 0 {
if m.Resid > m.ExpectedDataLen {
flag |= 0x04
} else if m.Resid < m.ExpectedDataLen {
flag |= 0x02
}
}
buf[1] = flag
//buf.WriteByte(0x00)
if m.HasStatus && m.Final == true {
flag = byte(m.Status)
}
//buf.WriteByte(flag)
buf[3] = flag
copy(buf[5:], util.MarshalUint64(uint64(m.DataLen))[5:])
// Skip through to byte 16 Since A bit is not set 11.7.4
copy(buf[16:], util.MarshalUint32(m.TaskTag))
copy(buf[24:], util.MarshalUint32(m.StatSN))
copy(buf[28:], util.MarshalUint32(m.ExpCmdSN))
copy(buf[32:], util.MarshalUint32(m.MaxCmdSN))
copy(buf[36:], util.MarshalUint32(m.DataSN))
copy(buf[40:], util.MarshalUint32(m.BufferOffset))
copy(buf[44:], util.MarshalUint32(m.Resid))
copy(buf[48:], m.RawData[m.BufferOffset:m.BufferOffset+uint32(m.DataLen)])
if m.ExpectedDataLen != 0 {
copy(buf[48:], m.RawData[m.BufferOffset:m.BufferOffset+uint32(m.DataLen)])
}
return buf
}
func (m *ISCSICommand) textRespBytes() []byte {
buf := bytes.Buffer{}
buf.WriteByte(byte(OpTextResp))
var b byte
if m.Final {
b |= 0x80
}
if m.Cont {
b |= 0x40
}
// byte 1
buf.WriteByte(b)
b = 0
buf.WriteByte(b)
buf.WriteByte(b)
buf.WriteByte(b)
buf.Write(util.MarshalUint64(uint64(len(m.RawData)))[5:]) // 5-8
// Skip through to byte 12
for i := 0; i < 2*4; i++ {
buf.WriteByte(0x00)
}
buf.Write(util.MarshalUint64(uint64(m.TaskTag))[4:])
for i := 0; i < 4; i++ {
buf.WriteByte(0xff)
}
buf.Write(util.MarshalUint64(uint64(m.StatSN))[4:])
buf.Write(util.MarshalUint64(uint64(m.ExpCmdSN))[4:])
buf.Write(util.MarshalUint64(uint64(m.MaxCmdSN))[4:])
for i := 0; i < 3*4; i++ {
buf.WriteByte(0x00)
}
rd := m.RawData
for len(rd)%4 != 0 {
rd = append(rd, 0)
}
buf.Write(rd)
return buf.Bytes()
}
func (m *ISCSICommand) noopInBytes() []byte {
buf := bytes.Buffer{}
buf.WriteByte(byte(OpNoopIn))
var b byte
b |= 0x80
// byte 1
buf.WriteByte(b)
b = 0
buf.WriteByte(b)
buf.WriteByte(b)
buf.WriteByte(b)
buf.Write(util.MarshalUint64(uint64(len(m.RawData)))[5:]) // 5-8
// Skip through to byte 12
for i := 0; i < 2*4; i++ {
buf.WriteByte(0x00)
}
buf.Write(util.MarshalUint64(uint64(m.TaskTag))[4:])
for i := 0; i < 4; i++ {
buf.WriteByte(0xff)
}
buf.Write(util.MarshalUint64(uint64(m.StatSN))[4:])
buf.Write(util.MarshalUint64(uint64(m.ExpCmdSN))[4:])
buf.Write(util.MarshalUint64(uint64(m.MaxCmdSN))[4:])
for i := 0; i < 3*4; i++ {
buf.WriteByte(0x00)
}
rd := m.RawData
for len(rd)%4 != 0 {
rd = append(rd, 0)
}
buf.Write(rd)
return buf.Bytes()
}
func (m *ISCSICommand) scsiTMFRespBytes() []byte {
// rfc7143 11.6
buf := bytes.Buffer{}
buf.WriteByte(byte(OpSCSITaskResp))
buf.WriteByte(0x80)
buf.WriteByte(m.Result)
buf.WriteByte(0x00)
// Skip through to byte 16
for i := 0; i < 3*4; i++ {
buf.WriteByte(0x00)
}
buf.Write(util.MarshalUint64(uint64(m.TaskTag))[4:])
for i := 0; i < 4; i++ {
buf.WriteByte(0x00)
}
buf.Write(util.MarshalUint64(uint64(m.StatSN))[4:])
buf.Write(util.MarshalUint64(uint64(m.ExpCmdSN))[4:])
buf.Write(util.MarshalUint64(uint64(m.MaxCmdSN))[4:])
for i := 0; i < 3*4; i++ {
buf.WriteByte(0x00)
}
return buf.Bytes()
}
func (m *ISCSICommand) r2tRespBytes() []byte {
// rfc7143 11.8
buf := bytes.Buffer{}
buf.WriteByte(byte(OpReady))
var b byte
if m.Final {
b |= 0x80
}
buf.WriteByte(b)
buf.WriteByte(0x00)
buf.WriteByte(0x00)
// Skip through to byte 16
for i := 0; i < 3*4; i++ {
buf.WriteByte(0x00)
}
buf.Write(util.MarshalUint64(uint64(m.TaskTag))[4:])
for i := 0; i < 4; i++ {
buf.WriteByte(0x00)
}
buf.Write(util.MarshalUint64(uint64(m.StatSN))[4:])
buf.Write(util.MarshalUint64(uint64(m.ExpCmdSN))[4:])
buf.Write(util.MarshalUint64(uint64(m.MaxCmdSN))[4:])
buf.Write(util.MarshalUint64(uint64(m.R2TSN))[4:])
buf.Write(util.MarshalUint64(uint64(m.BufferOffset))[4:])
buf.Write(util.MarshalUint64(uint64(m.DesiredLength))[4:])
return buf.Bytes()
}