EncryptKey/DecryptKey return whole PB message, not just value

[karelbilek]

EncryptKey/DecryptKey return whole PB message, not just value

This code just returns bytes from the PB message

cryptoWallet/internal/wallets/satoshilabs/trezor/trezor.go

Lines 124 to 127 in 47f9f68

	func (trezor *TrezorBase) CipherKeyValue(path string, isToEncrypt bool, keyName string, data, iv []byte, askOnEncode, askOnDecode bool) ([]byte, messages.MessageType) {
	result, msgType := trezor.call(trezor.Client.CipherKeyValue(isToEncrypt, keyName, data, tesoro.StringToBIP32Path(path), iv, askOnEncode, askOnDecode))
	return []byte(result), messages.MessageType(msgType)
	}

and that's used directly as a key here

cryptoWallet/internal/wallets/satoshilabs/trezor/trezor.go

Lines 186 to 196 in 47f9f68

	decryptedKey, msgType := trezor.CipherKeyValue(path, false, trezorKeyname, []byte(encryptedKeyhexValue), nonce, false, true)
	switch msgType {
	case messages.MessageType_MessageType_Success, messages.MessageType_MessageType_CipheredKeyValue:
	case messages.MessageType_MessageType_Failure:
	return nil, fmt.Errorf(`Got an error from a trezor device: %v (the trezor device is busy?)`, string(decryptedKey)) // if an error occurs then the error description is returned into "decryptedKey" as a string
	default:
	return nil, fmt.Errorf("Got an unexpected behaviour from a trezor device: %v: %v", msgType, string(encryptedKey))
	}
	return decryptedKey, nil

but it's never de-marshaled from protobuf.

https://github.com/trezor/trezor-common/blob/04bac52951764d5516206f5359cfc5f5c24eb38f/protob/messages-crypto.proto#L28-L30

[karelbilek]

I am currently re-writing xaionaro-go/cryptoWallet to use my fork of trezord-go as a library here

trezor/trezord-go#147

which will cause the code here to simplify a lot (I am basically removing all the intermediary classes) and improve the code here. (And I am also removing the dependency on tesoro, which is unmaintained.)

[karelbilek]

Similarly, Ping result is not de-marshaled, as isn't Features. (I wonder how could it work for you :D )

[karelbilek]

I see JSON unmarshaling here, which makes no sense, as JSON is not used anywhere in trezor

cryptoWallet/internal/wallets/satoshilabs/trezor/trezor.go

Line 99 in 57b96a3

err := json.Unmarshal([]byte(str), &response)

[xaionaro]

Hello. I have no time on Trezors right now, so the only thing I can do is review and merge patches :(

I see JSON unmarshaling here, which makes no sense, as JSON is not used anywhere in trezor

If this's true then it's very strange. Because I remember for sure that the answer was in JSON. May be the device returns it that way or something. Or, may be it's just obsolete.

Similarly, Ping result is not de-marshaled, as isn't Features. (I wonder how could it work for you :D )

Well, it really worked, too :)
I cannot answer anything here because of no time on investigations... Sorry :(

but it's never de-marshaled from protobuf.

Yep, seems to be a mistake.

[xaionaro]

UPD:

I've just looked into the code a little because I couldn't believe I was so careless. And it seems that actually everything is OK. The unmarshaling was done here:

https://github.com/conejoninja/tesoro/blob/master/tesoro.go#L864

And JSON messages are about there, too.

[karelbilek]

OH OK! I looked at wrong place. In that case, closing.

(as I said, I am rewriting this library + tesoro. I will make you a PR once it's done, but basically, at that point, this library will be basically almost empty.)