go-ntlmssp/negotiate_message.go

65 строки
1.5 KiB
Go

package ntlmssp
import (
"bytes"
"encoding/binary"
"errors"
"strings"
)
const expMsgBodyLen = 40
type negotiateMessageFields struct {
messageHeader
NegotiateFlags negotiateFlags
Domain varField
Workstation varField
Version
}
var defaultFlags = negotiateFlagNTLMSSPNEGOTIATETARGETINFO |
negotiateFlagNTLMSSPNEGOTIATE56 |
negotiateFlagNTLMSSPNEGOTIATE128 |
negotiateFlagNTLMSSPNEGOTIATEUNICODE |
negotiateFlagNTLMSSPNEGOTIATEEXTENDEDSESSIONSECURITY
//NewNegotiateMessage creates a new NEGOTIATE message with the
//flags that this package supports.
func NewNegotiateMessage(domainName, workstationName string) ([]byte, error) {
payloadOffset := expMsgBodyLen
flags := defaultFlags
if domainName != "" {
flags |= negotiateFlagNTLMSSPNEGOTIATEOEMDOMAINSUPPLIED
}
if workstationName != "" {
flags |= negotiateFlagNTLMSSPNEGOTIATEOEMWORKSTATIONSUPPLIED
}
msg := negotiateMessageFields{
messageHeader: newMessageHeader(1),
NegotiateFlags: flags,
Domain: newVarField(&payloadOffset, len(domainName)),
Workstation: newVarField(&payloadOffset, len(workstationName)),
Version: DefaultVersion(),
}
b := bytes.Buffer{}
if err := binary.Write(&b, binary.LittleEndian, &msg); err != nil {
return nil, err
}
if b.Len() != expMsgBodyLen {
return nil, errors.New("incorrect body length")
}
payload := strings.ToUpper(domainName + workstationName)
if _, err := b.WriteString(payload); err != nil {
return nil, err
}
return b.Bytes(), nil
}