add format

sign.go

@@ -6,6 +6,7 @@ import (
 	"crypto/rand"
 	"encoding/base64"
 	"encoding/hex"
+	"encoding/json"
 	"errors"
 	"github.com/ugorji/go/codec"
 	"hash/crc64"
@@ -16,7 +17,7 @@ const alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789
 
 var b64 = base64.NewEncoding(alphabet).WithPadding(base64.NoPadding)
 
-type linkData struct {
+type tokenData struct {
 	Signature []byte `codec:"s"`
 	Payload   []byte `codec:"p"`
 }
@@ -50,6 +51,42 @@ func (tc TokenCoder) SeedHex() string {
 	return hex.EncodeToString(tc.Seed())
 }
 
+func Format(token string) (txt string, err error) {
+	var payload any
+	var data []byte
+	data, err = b64.DecodeString(strings.TrimFunc(token, trim))
+	if err != nil {
+		return
+	}
+
+	buf := bytes.NewBuffer(nil)
+	var handle codec.CborHandle
+
+	buf.Write(data)
+	dec := codec.NewDecoder(buf, &handle)
+
+	var td tokenData
+	err = dec.Decode(&td)
+	if err != nil {
+		return
+	}
+
+	buf.Reset()
+	buf.Write(td.Payload)
+
+	err = dec.Decode(&payload)
+
+	buf.Reset()
+	buf.Write([]byte("SIGNATURE=" + hex.EncodeToString(td.Signature) + "\n"))
+
+	enc := json.NewEncoder(buf)
+	enc.SetEscapeHTML(false)
+	enc.SetIndent("", "\t")
+	err = enc.Encode(payload)
+	txt = buf.String()
+	return
+}
+
 func NewTokenCoderWithSeed(seed []byte, pubKeys ...[]byte) (tc TokenCoder, err error) {
 	if len(seed) != ed25519.SeedSize {
 		err = errors.New("Incorrect seed size")
@@ -123,11 +160,11 @@ func (tc TokenCoder) Encode(payload interface{}) (token string, err error) {
 	enc := codec.NewEncoder(buf, &handle)
 	enc.Encode(payload)
 
-	var ld linkData
+	var td tokenData
-	ld.Signature = ed25519.Sign(tc.privKey, buf.Bytes())
+	td.Signature = ed25519.Sign(tc.privKey, buf.Bytes())
-	ld.Payload = buf.Bytes()
+	td.Payload = buf.Bytes()
 	buf.Reset()
-	enc.Encode(ld)
+	enc.Encode(td)
 	token = b64.EncodeToString(buf.Bytes())
 	return
 }
@@ -150,15 +187,15 @@ func (tc TokenCoder) Decode(token string, payload interface{}) (sum string, err
 	buf.Write(data)
 	dec := codec.NewDecoder(buf, &handle)
 
-	var ld linkData
+	var td tokenData
-	err = dec.Decode(&ld)
+	err = dec.Decode(&td)
 	if err != nil {
 		return
 	}
 
 	ok := false
 	for _, key := range tc.pubKeys {
-		if ed25519.Verify(key, ld.Payload, ld.Signature) {
+		if ed25519.Verify(key, td.Payload, td.Signature) {
 			ok = true
 			break
 		}
@@ -170,10 +207,10 @@ func (tc TokenCoder) Decode(token string, payload interface{}) (sum string, err
 	}
 
 	buf.Reset()
-	buf.Write(ld.Payload)
+	buf.Write(td.Payload)
 
 	hash := crc64.New(crc64.MakeTable(crc64.ISO))
-	hash.Write(ld.Payload)
+	hash.Write(td.Payload)
 
 	sum = hex.EncodeToString(hash.Sum(nil))
 	err = dec.Decode(&payload)