fix(resolution): restore hex.Decode/Encode when loading/storing ciphered data from database (#395)

* fix(resolution): restore hex.Decode/Encode when loading/storing ciphered data from database

Previously, we were using symmecrypt.DecryptMarshal to load data from
the database, and we switched to symmecrypt.Decrypt with
bf23fbb.
This changed the behaviour because DecryptMarshal was also calling hex.Decode
on the ciphered text before doing the Decrypt. We had to restore this
behaviour to read old data from our database.
Same for EncryptMarshal/Encrypt/hex.Encode

Signed-off-by: Romain Beuque <556072+rbeuque74@users.noreply.github.com>

Author: rbeuque74

models/resolution/resolution.go

@@ -2,6 +2,7 @@ package resolution
 
 import (
 	"bytes"
+	"encoding/hex"
 	"encoding/json"
 	"time"
 
@@ -166,6 +167,9 @@ func Create(dbp zesty.DBProvider, t *task.Task, resolverInputs map[string]interf
 	if err != nil {
 		return nil, err
 	}
+
+	dst := make([]byte, hex.EncodedLen(len(encryptedSteps)))
+	hex.Encode(dst, encryptedSteps)
 	r.EncryptedSteps = encryptedSteps
 
 	err = tt.ValidateResolverInputs(resolverInputs)
@@ -247,7 +251,19 @@ func load(dbp zesty.DBProvider, publicID string, locked bool, lockNoWait bool) (
 		return nil, err
 	}
 
-	compressedSteps, err := models.EncryptionKey.Decrypt(r.EncryptedSteps, []byte(r.PublicID))
+	dst := make([]byte, hex.DecodedLen(len(r.EncryptedSteps)))
+
+	// if we can't hex Decode, we might be in the case of a Resolution row in database that was
+	// created between the v1.21.1 and v1.21.3 that was bugged, and failed to hex Encode/Decode the
+	// ciphered data. We need to keep backward compatibility for those, but this should not happen
+	// often.
+	// See https://github.com/ovh/utask/commit/bf23fbb10b62bb487ac4ea01b1e519f85480e58b and migration
+	// from symmecrypt.Key.DecryptMarshal to symmecrypt.Key.Decrypt
+	if _, err = hex.Decode(dst, r.EncryptedSteps); err != nil {
+		dst = r.EncryptedSteps
+	}
+
+	compressedSteps, err := models.EncryptionKey.Decrypt(dst, []byte(r.PublicID))
 	if err != nil {
 		return nil, err
 	}
@@ -377,6 +393,8 @@ func (r *Resolution) Update(dbp zesty.DBProvider) (err error) {
 		return err
 	}
 
+	dst := make([]byte, hex.EncodedLen(len(compressedSteps)))
+	hex.Encode(dst, compressedSteps)
 	encryptedSteps, err := models.EncryptionKey.Encrypt(compressedSteps, []byte(r.PublicID))
 	if err != nil {
 		return err