refactor/internal (#1216)

* refactor: update import paths in gateway handlers

* refactor: remove obsolete devtools Makefile and README

* build: optimize build process for improved efficiency

* refactor: remove obsolete pkl files related to Matrix and Sonr network configurations

* refactor: move embed code to x/dwn/types

internal/crypto/signatures/bbs/blind_signature.go

@@ -0,0 +1,79 @@
+//
+// Copyright Coinbase, Inc. All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+package bbs
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/onsonr/sonr/internal/crypto/core/curves"
+	"github.com/onsonr/sonr/internal/crypto/signatures/common"
+)
+
+// BlindSignature is a BBS+ blind signature
+// structurally identical to `Signature` but
+// is used to help avoid misuse and confusion.
+//
+// 1 or more message have been hidden by the
+// potential signature holder so the signer
+// only knows a subset of the messages to be signed
+type BlindSignature struct {
+	a    curves.PairingPoint
+	e, s curves.Scalar
+}
+
+// Init creates an empty signature to a specific curve
+// which should be followed by UnmarshalBinary
+func (sig *BlindSignature) Init(curve *curves.PairingCurve) *BlindSignature {
+	sig.a = curve.NewG1IdentityPoint()
+	sig.e = curve.NewScalar()
+	sig.s = curve.NewScalar()
+	return sig
+}
+
+func (sig BlindSignature) MarshalBinary() ([]byte, error) {
+	out := append(sig.a.ToAffineCompressed(), sig.e.Bytes()...)
+	out = append(out, sig.s.Bytes()...)
+	return out, nil
+}
+
+func (sig *BlindSignature) UnmarshalBinary(data []byte) error {
+	pointLength := len(sig.a.ToAffineCompressed())
+	scalarLength := len(sig.s.Bytes())
+	expectedLength := pointLength + scalarLength*2
+	if len(data) != expectedLength {
+		return fmt.Errorf("invalid byte sequence")
+	}
+	a, err := sig.a.FromAffineCompressed(data[:pointLength])
+	if err != nil {
+		return err
+	}
+	e, err := sig.e.SetBytes(data[pointLength:(pointLength + scalarLength)])
+	if err != nil {
+		return err
+	}
+	s, err := sig.s.SetBytes(data[(pointLength + scalarLength):])
+	if err != nil {
+		return err
+	}
+	var ok bool
+	sig.a, ok = a.(curves.PairingPoint)
+	if !ok {
+		return errors.New("incorrect type conversion")
+	}
+	sig.e = e
+	sig.s = s
+	return nil
+}
+
+func (sig BlindSignature) ToUnblinded(blinder common.SignatureBlinding) *Signature {
+	return &Signature{
+		a: sig.a,
+		e: sig.e,
+		s: sig.s.Add(blinder),
+	}
+}