cacert-gosigner/datastructures/signerresponse.go
2018-10-31 11:17:51 +01:00

64 lines
2 KiB
Go

package datastructures
import (
"bytes"
"errors"
"fmt"
)
type SignerResponse struct {
Version uint8
Action Action
Reserved1 uint8
Reserved2 uint8
Content1 string
Content2 string
Content3 string
}
func SignerResponseFromData(lengthBytes []byte, blockData []byte, checkSum byte) (*SignerResponse, error) {
headerLength := decode24BitLength(lengthBytes)
headerBytes := blockData[3 : 3+headerLength]
contentBytes := blockData[3+headerLength:]
content1Length := decode24BitLength(contentBytes[0:3])
content1 := string(contentBytes[3 : 3+content1Length])
content2Offset := 3 + content1Length
content2Length := decode24BitLength(contentBytes[content2Offset : content2Offset+3])
content2 := string(contentBytes[3+content2Offset : 3+content2Offset+content2Length])
content3Offset := 3 + content2Offset + content2Length
content3Length := decode24BitLength(contentBytes[content3Offset : content3Offset+3])
content3 := string(contentBytes[3+content3Offset : 3+content3Offset+content3Length])
calculated := CalculateXorCheckSum([][]byte{lengthBytes, blockData})
if checkSum != calculated {
return nil, errors.New(fmt.Sprintf("invalid checksum expected 0x%x got 0x%x", calculated, checkSum))
}
return &SignerResponse{
Version: headerBytes[0],
Action: Action(headerBytes[1]),
Reserved1: headerBytes[2],
Reserved2: headerBytes[3],
Content1: content1,
Content2: content2,
Content3: content3,
}, nil
}
func (r SignerResponse) Serialize() []byte {
headerBytes := []byte{r.Version, byte(r.Action), r.Reserved1, r.Reserved2}
content1Bytes := []byte(r.Content1)
content2Bytes := []byte(r.Content2)
content3Bytes := []byte(r.Content3)
blockBytes := bytes.Join([][]byte{
encode24BitLength(headerBytes), headerBytes,
encode24BitLength(content1Bytes), content1Bytes,
encode24BitLength(content2Bytes), content2Bytes,
encode24BitLength(content3Bytes), content3Bytes,
}, []byte{})
return bytes.Join([][]byte{encode24BitLength(blockBytes), blockBytes}, []byte{})
}