916 lines
22 KiB
Go
916 lines
22 KiB
Go
package mssql
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import (
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"context"
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"crypto/tls"
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"crypto/x509"
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"encoding/binary"
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"errors"
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"fmt"
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"io"
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"io/ioutil"
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"net"
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"sort"
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"strconv"
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"strings"
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"unicode/utf16"
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"unicode/utf8"
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)
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func parseInstances(msg []byte) map[string]map[string]string {
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results := map[string]map[string]string{}
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if len(msg) > 3 && msg[0] == 5 {
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out_s := string(msg[3:])
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tokens := strings.Split(out_s, ";")
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instdict := map[string]string{}
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got_name := false
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var name string
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for _, token := range tokens {
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if got_name {
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instdict[name] = token
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got_name = false
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} else {
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name = token
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if len(name) == 0 {
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if len(instdict) == 0 {
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break
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}
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results[strings.ToUpper(instdict["InstanceName"])] = instdict
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instdict = map[string]string{}
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continue
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}
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got_name = true
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}
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}
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}
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return results
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}
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func getInstances(ctx context.Context, d Dialer, address string) (map[string]map[string]string, error) {
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conn, err := d.DialContext(ctx, "udp", address+":1434")
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if err != nil {
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return nil, err
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}
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defer conn.Close()
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deadline, _ := ctx.Deadline()
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conn.SetDeadline(deadline)
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_, err = conn.Write([]byte{3})
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if err != nil {
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return nil, err
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}
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var resp = make([]byte, 16*1024-1)
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read, err := conn.Read(resp)
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if err != nil {
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return nil, err
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}
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return parseInstances(resp[:read]), nil
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}
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// tds versions
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const (
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verTDS70 = 0x70000000
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verTDS71 = 0x71000000
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verTDS71rev1 = 0x71000001
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verTDS72 = 0x72090002
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verTDS73A = 0x730A0003
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verTDS73 = verTDS73A
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verTDS73B = 0x730B0003
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verTDS74 = 0x74000004
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)
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// packet types
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// https://msdn.microsoft.com/en-us/library/dd304214.aspx
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const (
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packSQLBatch packetType = 1
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packRPCRequest = 3
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packReply = 4
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// 2.2.1.7 Attention: https://msdn.microsoft.com/en-us/library/dd341449.aspx
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// 4.19.2 Out-of-Band Attention Signal: https://msdn.microsoft.com/en-us/library/dd305167.aspx
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packAttention = 6
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packBulkLoadBCP = 7
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packTransMgrReq = 14
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packNormal = 15
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packLogin7 = 16
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packSSPIMessage = 17
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packPrelogin = 18
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)
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// prelogin fields
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// http://msdn.microsoft.com/en-us/library/dd357559.aspx
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const (
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preloginVERSION = 0
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preloginENCRYPTION = 1
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preloginINSTOPT = 2
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preloginTHREADID = 3
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preloginMARS = 4
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preloginTRACEID = 5
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preloginTERMINATOR = 0xff
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)
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const (
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encryptOff = 0 // Encryption is available but off.
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encryptOn = 1 // Encryption is available and on.
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encryptNotSup = 2 // Encryption is not available.
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encryptReq = 3 // Encryption is required.
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)
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type tdsSession struct {
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buf *tdsBuffer
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loginAck loginAckStruct
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database string
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partner string
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columns []columnStruct
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tranid uint64
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logFlags uint64
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log optionalLogger
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routedServer string
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routedPort uint16
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}
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const (
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logErrors = 1
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logMessages = 2
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logRows = 4
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logSQL = 8
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logParams = 16
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logTransaction = 32
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logDebug = 64
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)
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type columnStruct struct {
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UserType uint32
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Flags uint16
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ColName string
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ti typeInfo
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}
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type keySlice []uint8
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func (p keySlice) Len() int { return len(p) }
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func (p keySlice) Less(i, j int) bool { return p[i] < p[j] }
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func (p keySlice) Swap(i, j int) { p[i], p[j] = p[j], p[i] }
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// http://msdn.microsoft.com/en-us/library/dd357559.aspx
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func writePrelogin(w *tdsBuffer, fields map[uint8][]byte) error {
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var err error
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w.BeginPacket(packPrelogin, false)
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offset := uint16(5*len(fields) + 1)
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keys := make(keySlice, 0, len(fields))
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for k, _ := range fields {
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keys = append(keys, k)
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}
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sort.Sort(keys)
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// writing header
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for _, k := range keys {
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err = w.WriteByte(k)
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if err != nil {
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return err
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}
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err = binary.Write(w, binary.BigEndian, offset)
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if err != nil {
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return err
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}
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v := fields[k]
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size := uint16(len(v))
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err = binary.Write(w, binary.BigEndian, size)
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if err != nil {
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return err
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}
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offset += size
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}
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err = w.WriteByte(preloginTERMINATOR)
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if err != nil {
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return err
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}
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// writing values
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for _, k := range keys {
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v := fields[k]
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written, err := w.Write(v)
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if err != nil {
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return err
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}
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if written != len(v) {
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return errors.New("Write method didn't write the whole value")
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}
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}
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return w.FinishPacket()
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}
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func readPrelogin(r *tdsBuffer) (map[uint8][]byte, error) {
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packet_type, err := r.BeginRead()
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if err != nil {
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return nil, err
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}
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struct_buf, err := ioutil.ReadAll(r)
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if err != nil {
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return nil, err
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}
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if packet_type != 4 {
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return nil, errors.New("Invalid respones, expected packet type 4, PRELOGIN RESPONSE")
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}
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offset := 0
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results := map[uint8][]byte{}
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for true {
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rec_type := struct_buf[offset]
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if rec_type == preloginTERMINATOR {
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break
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}
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rec_offset := binary.BigEndian.Uint16(struct_buf[offset+1:])
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rec_len := binary.BigEndian.Uint16(struct_buf[offset+3:])
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value := struct_buf[rec_offset : rec_offset+rec_len]
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results[rec_type] = value
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offset += 5
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}
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return results, nil
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}
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// OptionFlags2
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// http://msdn.microsoft.com/en-us/library/dd304019.aspx
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const (
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fLanguageFatal = 1
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fODBC = 2
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fTransBoundary = 4
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fCacheConnect = 8
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fIntSecurity = 0x80
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)
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// TypeFlags
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const (
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// 4 bits for fSQLType
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// 1 bit for fOLEDB
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fReadOnlyIntent = 32
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)
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type login struct {
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TDSVersion uint32
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PacketSize uint32
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ClientProgVer uint32
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ClientPID uint32
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ConnectionID uint32
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OptionFlags1 uint8
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OptionFlags2 uint8
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TypeFlags uint8
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OptionFlags3 uint8
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ClientTimeZone int32
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ClientLCID uint32
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HostName string
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UserName string
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Password string
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AppName string
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ServerName string
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CtlIntName string
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Language string
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Database string
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ClientID [6]byte
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SSPI []byte
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AtchDBFile string
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ChangePassword string
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}
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type loginHeader struct {
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Length uint32
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TDSVersion uint32
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PacketSize uint32
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ClientProgVer uint32
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ClientPID uint32
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ConnectionID uint32
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OptionFlags1 uint8
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OptionFlags2 uint8
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TypeFlags uint8
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OptionFlags3 uint8
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ClientTimeZone int32
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ClientLCID uint32
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HostNameOffset uint16
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HostNameLength uint16
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UserNameOffset uint16
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UserNameLength uint16
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PasswordOffset uint16
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PasswordLength uint16
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AppNameOffset uint16
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AppNameLength uint16
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ServerNameOffset uint16
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ServerNameLength uint16
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ExtensionOffset uint16
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ExtensionLenght uint16
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CtlIntNameOffset uint16
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CtlIntNameLength uint16
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LanguageOffset uint16
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LanguageLength uint16
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DatabaseOffset uint16
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DatabaseLength uint16
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ClientID [6]byte
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SSPIOffset uint16
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SSPILength uint16
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AtchDBFileOffset uint16
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AtchDBFileLength uint16
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ChangePasswordOffset uint16
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ChangePasswordLength uint16
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SSPILongLength uint32
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}
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// convert Go string to UTF-16 encoded []byte (littleEndian)
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// done manually rather than using bytes and binary packages
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// for performance reasons
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func str2ucs2(s string) []byte {
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res := utf16.Encode([]rune(s))
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ucs2 := make([]byte, 2*len(res))
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for i := 0; i < len(res); i++ {
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ucs2[2*i] = byte(res[i])
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ucs2[2*i+1] = byte(res[i] >> 8)
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}
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return ucs2
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}
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func ucs22str(s []byte) (string, error) {
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if len(s)%2 != 0 {
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return "", fmt.Errorf("Illegal UCS2 string length: %d", len(s))
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}
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buf := make([]uint16, len(s)/2)
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for i := 0; i < len(s); i += 2 {
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buf[i/2] = binary.LittleEndian.Uint16(s[i:])
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}
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return string(utf16.Decode(buf)), nil
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}
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func manglePassword(password string) []byte {
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var ucs2password []byte = str2ucs2(password)
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for i, ch := range ucs2password {
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ucs2password[i] = ((ch<<4)&0xff | (ch >> 4)) ^ 0xA5
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}
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return ucs2password
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}
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// http://msdn.microsoft.com/en-us/library/dd304019.aspx
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func sendLogin(w *tdsBuffer, login login) error {
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w.BeginPacket(packLogin7, false)
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hostname := str2ucs2(login.HostName)
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username := str2ucs2(login.UserName)
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password := manglePassword(login.Password)
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appname := str2ucs2(login.AppName)
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servername := str2ucs2(login.ServerName)
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ctlintname := str2ucs2(login.CtlIntName)
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language := str2ucs2(login.Language)
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database := str2ucs2(login.Database)
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atchdbfile := str2ucs2(login.AtchDBFile)
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changepassword := str2ucs2(login.ChangePassword)
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hdr := loginHeader{
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TDSVersion: login.TDSVersion,
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PacketSize: login.PacketSize,
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ClientProgVer: login.ClientProgVer,
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ClientPID: login.ClientPID,
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ConnectionID: login.ConnectionID,
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OptionFlags1: login.OptionFlags1,
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OptionFlags2: login.OptionFlags2,
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TypeFlags: login.TypeFlags,
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OptionFlags3: login.OptionFlags3,
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ClientTimeZone: login.ClientTimeZone,
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ClientLCID: login.ClientLCID,
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HostNameLength: uint16(utf8.RuneCountInString(login.HostName)),
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UserNameLength: uint16(utf8.RuneCountInString(login.UserName)),
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PasswordLength: uint16(utf8.RuneCountInString(login.Password)),
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AppNameLength: uint16(utf8.RuneCountInString(login.AppName)),
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ServerNameLength: uint16(utf8.RuneCountInString(login.ServerName)),
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CtlIntNameLength: uint16(utf8.RuneCountInString(login.CtlIntName)),
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LanguageLength: uint16(utf8.RuneCountInString(login.Language)),
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DatabaseLength: uint16(utf8.RuneCountInString(login.Database)),
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ClientID: login.ClientID,
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SSPILength: uint16(len(login.SSPI)),
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AtchDBFileLength: uint16(utf8.RuneCountInString(login.AtchDBFile)),
|
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ChangePasswordLength: uint16(utf8.RuneCountInString(login.ChangePassword)),
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}
|
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offset := uint16(binary.Size(hdr))
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hdr.HostNameOffset = offset
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offset += uint16(len(hostname))
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hdr.UserNameOffset = offset
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offset += uint16(len(username))
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hdr.PasswordOffset = offset
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offset += uint16(len(password))
|
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hdr.AppNameOffset = offset
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offset += uint16(len(appname))
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hdr.ServerNameOffset = offset
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offset += uint16(len(servername))
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hdr.CtlIntNameOffset = offset
|
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offset += uint16(len(ctlintname))
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hdr.LanguageOffset = offset
|
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offset += uint16(len(language))
|
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hdr.DatabaseOffset = offset
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offset += uint16(len(database))
|
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hdr.SSPIOffset = offset
|
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offset += uint16(len(login.SSPI))
|
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hdr.AtchDBFileOffset = offset
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offset += uint16(len(atchdbfile))
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hdr.ChangePasswordOffset = offset
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offset += uint16(len(changepassword))
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hdr.Length = uint32(offset)
|
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var err error
|
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err = binary.Write(w, binary.LittleEndian, &hdr)
|
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if err != nil {
|
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return err
|
|
}
|
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_, err = w.Write(hostname)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
_, err = w.Write(username)
|
|
if err != nil {
|
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return err
|
|
}
|
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_, err = w.Write(password)
|
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if err != nil {
|
|
return err
|
|
}
|
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_, err = w.Write(appname)
|
|
if err != nil {
|
|
return err
|
|
}
|
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_, err = w.Write(servername)
|
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if err != nil {
|
|
return err
|
|
}
|
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_, err = w.Write(ctlintname)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
_, err = w.Write(language)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
_, err = w.Write(database)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
_, err = w.Write(login.SSPI)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
_, err = w.Write(atchdbfile)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
_, err = w.Write(changepassword)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
return w.FinishPacket()
|
|
}
|
|
|
|
func readUcs2(r io.Reader, numchars int) (res string, err error) {
|
|
buf := make([]byte, numchars*2)
|
|
_, err = io.ReadFull(r, buf)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
return ucs22str(buf)
|
|
}
|
|
|
|
func readUsVarChar(r io.Reader) (res string, err error) {
|
|
numchars, err := readUshort(r)
|
|
if err != nil {
|
|
return
|
|
}
|
|
return readUcs2(r, int(numchars))
|
|
}
|
|
|
|
func writeUsVarChar(w io.Writer, s string) (err error) {
|
|
buf := str2ucs2(s)
|
|
var numchars int = len(buf) / 2
|
|
if numchars > 0xffff {
|
|
panic("invalid size for US_VARCHAR")
|
|
}
|
|
err = binary.Write(w, binary.LittleEndian, uint16(numchars))
|
|
if err != nil {
|
|
return
|
|
}
|
|
_, err = w.Write(buf)
|
|
return
|
|
}
|
|
|
|
func readBVarChar(r io.Reader) (res string, err error) {
|
|
numchars, err := readByte(r)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
|
|
// A zero length could be returned, return an empty string
|
|
if numchars == 0 {
|
|
return "", nil
|
|
}
|
|
return readUcs2(r, int(numchars))
|
|
}
|
|
|
|
func writeBVarChar(w io.Writer, s string) (err error) {
|
|
buf := str2ucs2(s)
|
|
var numchars int = len(buf) / 2
|
|
if numchars > 0xff {
|
|
panic("invalid size for B_VARCHAR")
|
|
}
|
|
err = binary.Write(w, binary.LittleEndian, uint8(numchars))
|
|
if err != nil {
|
|
return
|
|
}
|
|
_, err = w.Write(buf)
|
|
return
|
|
}
|
|
|
|
func readBVarByte(r io.Reader) (res []byte, err error) {
|
|
length, err := readByte(r)
|
|
if err != nil {
|
|
return
|
|
}
|
|
res = make([]byte, length)
|
|
_, err = io.ReadFull(r, res)
|
|
return
|
|
}
|
|
|
|
func readUshort(r io.Reader) (res uint16, err error) {
|
|
err = binary.Read(r, binary.LittleEndian, &res)
|
|
return
|
|
}
|
|
|
|
func readByte(r io.Reader) (res byte, err error) {
|
|
var b [1]byte
|
|
_, err = r.Read(b[:])
|
|
res = b[0]
|
|
return
|
|
}
|
|
|
|
// Packet Data Stream Headers
|
|
// http://msdn.microsoft.com/en-us/library/dd304953.aspx
|
|
type headerStruct struct {
|
|
hdrtype uint16
|
|
data []byte
|
|
}
|
|
|
|
const (
|
|
dataStmHdrQueryNotif = 1 // query notifications
|
|
dataStmHdrTransDescr = 2 // MARS transaction descriptor (required)
|
|
dataStmHdrTraceActivity = 3
|
|
)
|
|
|
|
// Query Notifications Header
|
|
// http://msdn.microsoft.com/en-us/library/dd304949.aspx
|
|
type queryNotifHdr struct {
|
|
notifyId string
|
|
ssbDeployment string
|
|
notifyTimeout uint32
|
|
}
|
|
|
|
func (hdr queryNotifHdr) pack() (res []byte) {
|
|
notifyId := str2ucs2(hdr.notifyId)
|
|
ssbDeployment := str2ucs2(hdr.ssbDeployment)
|
|
|
|
res = make([]byte, 2+len(notifyId)+2+len(ssbDeployment)+4)
|
|
b := res
|
|
|
|
binary.LittleEndian.PutUint16(b, uint16(len(notifyId)))
|
|
b = b[2:]
|
|
copy(b, notifyId)
|
|
b = b[len(notifyId):]
|
|
|
|
binary.LittleEndian.PutUint16(b, uint16(len(ssbDeployment)))
|
|
b = b[2:]
|
|
copy(b, ssbDeployment)
|
|
b = b[len(ssbDeployment):]
|
|
|
|
binary.LittleEndian.PutUint32(b, hdr.notifyTimeout)
|
|
|
|
return res
|
|
}
|
|
|
|
// MARS Transaction Descriptor Header
|
|
// http://msdn.microsoft.com/en-us/library/dd340515.aspx
|
|
type transDescrHdr struct {
|
|
transDescr uint64 // transaction descriptor returned from ENVCHANGE
|
|
outstandingReqCnt uint32 // outstanding request count
|
|
}
|
|
|
|
func (hdr transDescrHdr) pack() (res []byte) {
|
|
res = make([]byte, 8+4)
|
|
binary.LittleEndian.PutUint64(res, hdr.transDescr)
|
|
binary.LittleEndian.PutUint32(res[8:], hdr.outstandingReqCnt)
|
|
return res
|
|
}
|
|
|
|
func writeAllHeaders(w io.Writer, headers []headerStruct) (err error) {
|
|
// Calculating total length.
|
|
var totallen uint32 = 4
|
|
for _, hdr := range headers {
|
|
totallen += 4 + 2 + uint32(len(hdr.data))
|
|
}
|
|
// writing
|
|
err = binary.Write(w, binary.LittleEndian, totallen)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
for _, hdr := range headers {
|
|
var headerlen uint32 = 4 + 2 + uint32(len(hdr.data))
|
|
err = binary.Write(w, binary.LittleEndian, headerlen)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
err = binary.Write(w, binary.LittleEndian, hdr.hdrtype)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
_, err = w.Write(hdr.data)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func sendSqlBatch72(buf *tdsBuffer, sqltext string, headers []headerStruct, resetSession bool) (err error) {
|
|
buf.BeginPacket(packSQLBatch, resetSession)
|
|
|
|
if err = writeAllHeaders(buf, headers); err != nil {
|
|
return
|
|
}
|
|
|
|
_, err = buf.Write(str2ucs2(sqltext))
|
|
if err != nil {
|
|
return
|
|
}
|
|
return buf.FinishPacket()
|
|
}
|
|
|
|
// 2.2.1.7 Attention: https://msdn.microsoft.com/en-us/library/dd341449.aspx
|
|
// 4.19.2 Out-of-Band Attention Signal: https://msdn.microsoft.com/en-us/library/dd305167.aspx
|
|
func sendAttention(buf *tdsBuffer) error {
|
|
buf.BeginPacket(packAttention, false)
|
|
return buf.FinishPacket()
|
|
}
|
|
|
|
type auth interface {
|
|
InitialBytes() ([]byte, error)
|
|
NextBytes([]byte) ([]byte, error)
|
|
Free()
|
|
}
|
|
|
|
// SQL Server AlwaysOn Availability Group Listeners are bound by DNS to a
|
|
// list of IP addresses. So if there is more than one, try them all and
|
|
// use the first one that allows a connection.
|
|
func dialConnection(ctx context.Context, c *Connector, p connectParams) (conn net.Conn, err error) {
|
|
var ips []net.IP
|
|
ips, err = net.LookupIP(p.host)
|
|
if err != nil {
|
|
ip := net.ParseIP(p.host)
|
|
if ip == nil {
|
|
return nil, err
|
|
}
|
|
ips = []net.IP{ip}
|
|
}
|
|
if len(ips) == 1 {
|
|
d := c.getDialer(&p)
|
|
addr := net.JoinHostPort(ips[0].String(), strconv.Itoa(int(resolveServerPort(p.port))))
|
|
conn, err = d.DialContext(ctx, "tcp", addr)
|
|
|
|
} else {
|
|
//Try Dials in parallel to avoid waiting for timeouts.
|
|
connChan := make(chan net.Conn, len(ips))
|
|
errChan := make(chan error, len(ips))
|
|
portStr := strconv.Itoa(int(resolveServerPort(p.port)))
|
|
for _, ip := range ips {
|
|
go func(ip net.IP) {
|
|
d := c.getDialer(&p)
|
|
addr := net.JoinHostPort(ip.String(), portStr)
|
|
conn, err := d.DialContext(ctx, "tcp", addr)
|
|
if err == nil {
|
|
connChan <- conn
|
|
} else {
|
|
errChan <- err
|
|
}
|
|
}(ip)
|
|
}
|
|
// Wait for either the *first* successful connection, or all the errors
|
|
wait_loop:
|
|
for i, _ := range ips {
|
|
select {
|
|
case conn = <-connChan:
|
|
// Got a connection to use, close any others
|
|
go func(n int) {
|
|
for i := 0; i < n; i++ {
|
|
select {
|
|
case conn := <-connChan:
|
|
conn.Close()
|
|
case <-errChan:
|
|
}
|
|
}
|
|
}(len(ips) - i - 1)
|
|
// Remove any earlier errors we may have collected
|
|
err = nil
|
|
break wait_loop
|
|
case err = <-errChan:
|
|
}
|
|
}
|
|
}
|
|
// Can't do the usual err != nil check, as it is possible to have gotten an error before a successful connection
|
|
if conn == nil {
|
|
f := "Unable to open tcp connection with host '%v:%v': %v"
|
|
return nil, fmt.Errorf(f, p.host, resolveServerPort(p.port), err.Error())
|
|
}
|
|
return conn, err
|
|
}
|
|
|
|
func connect(ctx context.Context, c *Connector, log optionalLogger, p connectParams) (res *tdsSession, err error) {
|
|
dialCtx := ctx
|
|
if p.dial_timeout > 0 {
|
|
var cancel func()
|
|
dialCtx, cancel = context.WithTimeout(ctx, p.dial_timeout)
|
|
defer cancel()
|
|
}
|
|
// if instance is specified use instance resolution service
|
|
if p.instance != "" && p.port == 0 {
|
|
p.instance = strings.ToUpper(p.instance)
|
|
d := c.getDialer(&p)
|
|
instances, err := getInstances(dialCtx, d, p.host)
|
|
if err != nil {
|
|
f := "Unable to get instances from Sql Server Browser on host %v: %v"
|
|
return nil, fmt.Errorf(f, p.host, err.Error())
|
|
}
|
|
strport, ok := instances[p.instance]["tcp"]
|
|
if !ok {
|
|
f := "No instance matching '%v' returned from host '%v'"
|
|
return nil, fmt.Errorf(f, p.instance, p.host)
|
|
}
|
|
port, err := strconv.ParseUint(strport, 0, 16)
|
|
if err != nil {
|
|
f := "Invalid tcp port returned from Sql Server Browser '%v': %v"
|
|
return nil, fmt.Errorf(f, strport, err.Error())
|
|
}
|
|
p.port = port
|
|
}
|
|
|
|
initiate_connection:
|
|
conn, err := dialConnection(dialCtx, c, p)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
toconn := newTimeoutConn(conn, p.conn_timeout)
|
|
|
|
outbuf := newTdsBuffer(p.packetSize, toconn)
|
|
sess := tdsSession{
|
|
buf: outbuf,
|
|
log: log,
|
|
logFlags: p.logFlags,
|
|
}
|
|
|
|
instance_buf := []byte(p.instance)
|
|
instance_buf = append(instance_buf, 0) // zero terminate instance name
|
|
var encrypt byte
|
|
if p.disableEncryption {
|
|
encrypt = encryptNotSup
|
|
} else if p.encrypt {
|
|
encrypt = encryptOn
|
|
} else {
|
|
encrypt = encryptOff
|
|
}
|
|
fields := map[uint8][]byte{
|
|
preloginVERSION: {0, 0, 0, 0, 0, 0},
|
|
preloginENCRYPTION: {encrypt},
|
|
preloginINSTOPT: instance_buf,
|
|
preloginTHREADID: {0, 0, 0, 0},
|
|
preloginMARS: {0}, // MARS disabled
|
|
}
|
|
|
|
err = writePrelogin(outbuf, fields)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
fields, err = readPrelogin(outbuf)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
encryptBytes, ok := fields[preloginENCRYPTION]
|
|
if !ok {
|
|
return nil, fmt.Errorf("Encrypt negotiation failed")
|
|
}
|
|
encrypt = encryptBytes[0]
|
|
if p.encrypt && (encrypt == encryptNotSup || encrypt == encryptOff) {
|
|
return nil, fmt.Errorf("Server does not support encryption")
|
|
}
|
|
|
|
if encrypt != encryptNotSup {
|
|
var config tls.Config
|
|
if p.certificate != "" {
|
|
pem, err := ioutil.ReadFile(p.certificate)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("Cannot read certificate %q: %v", p.certificate, err)
|
|
}
|
|
certs := x509.NewCertPool()
|
|
certs.AppendCertsFromPEM(pem)
|
|
config.RootCAs = certs
|
|
}
|
|
if p.trustServerCertificate {
|
|
config.InsecureSkipVerify = true
|
|
}
|
|
config.ServerName = p.hostInCertificate
|
|
// fix for https://github.com/denisenkom/go-mssqldb/issues/166
|
|
// Go implementation of TLS payload size heuristic algorithm splits single TDS package to multiple TCP segments,
|
|
// while SQL Server seems to expect one TCP segment per encrypted TDS package.
|
|
// Setting DynamicRecordSizingDisabled to true disables that algorithm and uses 16384 bytes per TLS package
|
|
config.DynamicRecordSizingDisabled = true
|
|
// setting up connection handler which will allow wrapping of TLS handshake packets inside TDS stream
|
|
handshakeConn := tlsHandshakeConn{buf: outbuf}
|
|
passthrough := passthroughConn{c: &handshakeConn}
|
|
tlsConn := tls.Client(&passthrough, &config)
|
|
err = tlsConn.Handshake()
|
|
passthrough.c = toconn
|
|
outbuf.transport = tlsConn
|
|
if err != nil {
|
|
return nil, fmt.Errorf("TLS Handshake failed: %v", err)
|
|
}
|
|
if encrypt == encryptOff {
|
|
outbuf.afterFirst = func() {
|
|
outbuf.transport = toconn
|
|
}
|
|
}
|
|
}
|
|
|
|
login := login{
|
|
TDSVersion: verTDS74,
|
|
PacketSize: uint32(outbuf.PackageSize()),
|
|
Database: p.database,
|
|
OptionFlags2: fODBC, // to get unlimited TEXTSIZE
|
|
HostName: p.workstation,
|
|
ServerName: p.host,
|
|
AppName: p.appname,
|
|
TypeFlags: p.typeFlags,
|
|
}
|
|
auth, auth_ok := getAuth(p.user, p.password, p.serverSPN, p.workstation)
|
|
if auth_ok {
|
|
login.SSPI, err = auth.InitialBytes()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
login.OptionFlags2 |= fIntSecurity
|
|
defer auth.Free()
|
|
} else {
|
|
login.UserName = p.user
|
|
login.Password = p.password
|
|
}
|
|
err = sendLogin(outbuf, login)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
// processing login response
|
|
success := false
|
|
for {
|
|
tokchan := make(chan tokenStruct, 5)
|
|
go processResponse(context.Background(), &sess, tokchan, nil)
|
|
for tok := range tokchan {
|
|
switch token := tok.(type) {
|
|
case sspiMsg:
|
|
sspi_msg, err := auth.NextBytes(token)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if sspi_msg != nil && len(sspi_msg) > 0 {
|
|
outbuf.BeginPacket(packSSPIMessage, false)
|
|
_, err = outbuf.Write(sspi_msg)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
err = outbuf.FinishPacket()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
sspi_msg = nil
|
|
}
|
|
case loginAckStruct:
|
|
success = true
|
|
sess.loginAck = token
|
|
case error:
|
|
return nil, fmt.Errorf("Login error: %s", token.Error())
|
|
case doneStruct:
|
|
if token.isError() {
|
|
return nil, fmt.Errorf("Login error: %s", token.getError())
|
|
}
|
|
goto loginEnd
|
|
}
|
|
}
|
|
}
|
|
loginEnd:
|
|
if !success {
|
|
return nil, fmt.Errorf("Login failed")
|
|
}
|
|
if sess.routedServer != "" {
|
|
toconn.Close()
|
|
p.host = sess.routedServer
|
|
p.port = uint64(sess.routedPort)
|
|
if !p.hostInCertificateProvided {
|
|
p.hostInCertificate = sess.routedServer
|
|
}
|
|
goto initiate_connection
|
|
}
|
|
return &sess, nil
|
|
}
|