1 files changed, 152 insertions, 0 deletions
diff --git a/vendor/go.mau.fi/libsignal/protocol/PreKeySignalMessage.go b/vendor/go.mau.fi/libsignal/protocol/PreKeySignalMessage.go
new file mode 100644
index 00000000..841d9d17
--- /dev/null
+++ b/vendor/go.mau.fi/libsignal/protocol/PreKeySignalMessage.go
@@ -0,0 +1,152 @@
+package protocol
+
+import (
+	"fmt"
+
+	"go.mau.fi/libsignal/ecc"
+	"go.mau.fi/libsignal/keys/identity"
+	"go.mau.fi/libsignal/signalerror"
+	"go.mau.fi/libsignal/util/optional"
+)
+
+// PreKeySignalMessageSerializer is an interface for serializing and deserializing
+// PreKeySignalMessages into bytes. An implementation of this interface should be
+// used to encode/decode the object into JSON, Protobuffers, etc.
+type PreKeySignalMessageSerializer interface {
+	Serialize(signalMessage *PreKeySignalMessageStructure) []byte
+	Deserialize(serialized []byte) (*PreKeySignalMessageStructure, error)
+}
+
+// NewPreKeySignalMessageFromBytes will return a Signal Ciphertext message from the given
+// bytes using the given serializer.
+func NewPreKeySignalMessageFromBytes(serialized []byte, serializer PreKeySignalMessageSerializer,
+	msgSerializer SignalMessageSerializer) (*PreKeySignalMessage, error) {
+	// Use the given serializer to decode the signal message.
+	signalMessageStructure, err := serializer.Deserialize(serialized)
+	if err != nil {
+		return nil, err
+	}
+
+	return NewPreKeySignalMessageFromStruct(signalMessageStructure, serializer, msgSerializer)
+}
+
+// NewPreKeySignalMessageFromStruct will return a new PreKeySignalMessage from the given
+// PreKeySignalMessageStructure.
+func NewPreKeySignalMessageFromStruct(structure *PreKeySignalMessageStructure,
+	serializer PreKeySignalMessageSerializer, msgSerializer SignalMessageSerializer) (*PreKeySignalMessage, error) {
+
+	// Throw an error if the given message structure is an unsupported version.
+	if structure.Version <= UnsupportedVersion {
+		return nil, fmt.Errorf("%w %d (prekey message)", signalerror.ErrOldMessageVersion, structure.Version)
+	}
+
+	// Throw an error if the given message structure is a future version.
+	if structure.Version > CurrentVersion {
+		return nil, fmt.Errorf("%w %d (prekey message)", signalerror.ErrUnknownMessageVersion, structure.Version)
+	}
+
+	// Throw an error if the structure is missing critical fields.
+	if structure.BaseKey == nil || structure.IdentityKey == nil || structure.Message == nil {
+		return nil, fmt.Errorf("%w (prekey message)", signalerror.ErrIncompleteMessage)
+	}
+
+	// Create the signal message object from the structure.
+	preKeyWhisperMessage := &PreKeySignalMessage{structure: *structure, serializer: serializer}
+
+	// Generate the base ECC key from bytes.
+	var err error
+	preKeyWhisperMessage.baseKey, err = ecc.DecodePoint(structure.BaseKey, 0)
+	if err != nil {
+		return nil, err
+	}
+
+	// Generate the identity key from bytes
+	var identityKey ecc.ECPublicKeyable
+	identityKey, err = ecc.DecodePoint(structure.IdentityKey, 0)
+	if err != nil {
+		return nil, err
+	}
+	preKeyWhisperMessage.identityKey = identity.NewKey(identityKey)
+
+	// Generate the SignalMessage object from bytes.
+	preKeyWhisperMessage.message, err = NewSignalMessageFromBytes(structure.Message, msgSerializer)
+	if err != nil {
+		return nil, err
+	}
+
+	return preKeyWhisperMessage, nil
+}
+
+// NewPreKeySignalMessage will return a new PreKeySignalMessage object.
+func NewPreKeySignalMessage(version int, registrationID uint32, preKeyID *optional.Uint32, signedPreKeyID uint32,
+	baseKey ecc.ECPublicKeyable, identityKey *identity.Key, message *SignalMessage, serializer PreKeySignalMessageSerializer,
+	msgSerializer SignalMessageSerializer) (*PreKeySignalMessage, error) {
+	structure := &PreKeySignalMessageStructure{
+		Version:        version,
+		RegistrationID: registrationID,
+		PreKeyID:       preKeyID,
+		SignedPreKeyID: signedPreKeyID,
+		BaseKey:        baseKey.Serialize(),
+		IdentityKey:    identityKey.PublicKey().Serialize(),
+		Message:        message.Serialize(),
+	}
+	return NewPreKeySignalMessageFromStruct(structure, serializer, msgSerializer)
+}
+
+// PreKeySignalMessageStructure is a serializable structure for
+// PreKeySignalMessages.
+type PreKeySignalMessageStructure struct {
+	RegistrationID uint32
+	PreKeyID       *optional.Uint32
+	SignedPreKeyID uint32
+	BaseKey        []byte
+	IdentityKey    []byte
+	Message        []byte
+	Version        int
+}
+
+// PreKeySignalMessage is an encrypted Signal message that is designed
+// to be used when building a session with someone for the first time.
+type PreKeySignalMessage struct {
+	structure   PreKeySignalMessageStructure
+	baseKey     ecc.ECPublicKeyable
+	identityKey *identity.Key
+	message     *SignalMessage
+	serializer  PreKeySignalMessageSerializer
+}
+
+func (p *PreKeySignalMessage) MessageVersion() int {
+	return p.structure.Version
+}
+
+func (p *PreKeySignalMessage) IdentityKey() *identity.Key {
+	return p.identityKey
+}
+
+func (p *PreKeySignalMessage) RegistrationID() uint32 {
+	return p.structure.RegistrationID
+}
+
+func (p *PreKeySignalMessage) PreKeyID() *optional.Uint32 {
+	return p.structure.PreKeyID
+}
+
+func (p *PreKeySignalMessage) SignedPreKeyID() uint32 {
+	return p.structure.SignedPreKeyID
+}
+
+func (p *PreKeySignalMessage) BaseKey() ecc.ECPublicKeyable {
+	return p.baseKey
+}
+
+func (p *PreKeySignalMessage) WhisperMessage() *SignalMessage {
+	return p.message
+}
+
+func (p *PreKeySignalMessage) Serialize() []byte {
+	return p.serializer.Serialize(&p.structure)
+}
+
+func (p *PreKeySignalMessage) Type() uint32 {
+	return PREKEY_TYPE
+}