refactor to mautrix 0.17.x; update deps

vendor/maunium.net/go/mautrix/crypto/goolm/pk/signing.go

@@ -0,0 +1,44 @@
+package pk
+
+import (
+	"crypto/rand"
+
+	"maunium.net/go/mautrix/crypto/goolm"
+	"maunium.net/go/mautrix/crypto/goolm/crypto"
+	"maunium.net/go/mautrix/id"
+)
+
+// Signing is used for signing a pk
+type Signing struct {
+	KeyPair crypto.Ed25519KeyPair `json:"key_pair"`
+	Seed    []byte                `json:"seed"`
+}
+
+// NewSigningFromSeed constructs a new Signing based on a seed.
+func NewSigningFromSeed(seed []byte) (*Signing, error) {
+	s := &Signing{}
+	s.Seed = seed
+	s.KeyPair = crypto.Ed25519GenerateFromSeed(seed)
+	return s, nil
+}
+
+// NewSigning returns a Signing based on a random seed
+func NewSigning() (*Signing, error) {
+	seed := make([]byte, 32)
+	_, err := rand.Read(seed)
+	if err != nil {
+		return nil, err
+	}
+	return NewSigningFromSeed(seed)
+}
+
+// Sign returns the signature of the message base64 encoded.
+func (s Signing) Sign(message []byte) []byte {
+	signature := s.KeyPair.Sign(message)
+	return goolm.Base64Encode(signature)
+}
+
+// PublicKey returns the public key of the key pair base 64 encoded.
+func (s Signing) PublicKey() id.Ed25519 {
+	return s.KeyPair.B64Encoded()
+}