Release v0.3.0

vendor/github.com/btcsuite/btcutil/psbt/partialsig.go

@@ -0,0 +1,58 @@
+package psbt
+
+import (
+	"bytes"
+
+	"github.com/btcsuite/btcd/btcec"
+)
+
+// PartialSig encapsulate a (BTC public key, ECDSA signature)
+// pair, note that the fields are stored as byte slices, not
+// btcec.PublicKey or btcec.Signature (because manipulations will
+// be with the former not the latter, here); compliance with consensus
+// serialization is enforced with .checkValid()
+type PartialSig struct {
+	PubKey    []byte
+	Signature []byte
+}
+
+// PartialSigSorter implements sort.Interface for PartialSig.
+type PartialSigSorter []*PartialSig
+
+func (s PartialSigSorter) Len() int { return len(s) }
+
+func (s PartialSigSorter) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
+
+func (s PartialSigSorter) Less(i, j int) bool {
+	return bytes.Compare(s[i].PubKey, s[j].PubKey) < 0
+}
+
+// validatePubkey checks if pubKey is *any* valid pubKey serialization in a
+// Bitcoin context (compressed/uncomp. OK).
+func validatePubkey(pubKey []byte) bool {
+	_, err := btcec.ParsePubKey(pubKey, btcec.S256())
+	if err != nil {
+		return false
+	}
+	return true
+}
+
+// validateSignature checks that the passed byte slice is a valid DER-encoded
+// ECDSA signature, including the sighash flag.  It does *not* of course
+// validate the signature against any message or public key.
+func validateSignature(sig []byte) bool {
+	_, err := btcec.ParseDERSignature(sig, btcec.S256())
+	if err != nil {
+		return false
+	}
+	return true
+}
+
+// checkValid checks that both the pbukey and sig are valid. See the methods
+// (PartialSig, validatePubkey, validateSignature) for more details.
+//
+// TODO(waxwing): update for Schnorr will be needed here if/when that
+// activates.
+func (ps *PartialSig) checkValid() bool {
+	return validatePubkey(ps.PubKey) && validateSignature(ps.Signature)
+}