address issue #198, converting MIRACL signature to herumi signature

code/go/0chain.net/blobbercore/handler/storage_handler.go

@@ -700,7 +700,7 @@ func (fsh *StorageHandler) CalculateHash(ctx context.Context, r *http.Request) (
 
 // verifySignatureFromRequest verifyes signature passed as common.ClientSignatureHeader header.
 func verifySignatureFromRequest(r *http.Request, pbK string) (bool, error) {
-	sign := r.Header.Get(common.ClientSignatureHeader)
+	sign := encryption.MiraclToHerumiSig(r.Header.Get(common.ClientSignatureHeader))
 	if len(sign) < 64 {
 		return false, nil
 	}

code/go/0chain.net/core/encryption/keys.go

@@ -3,6 +3,7 @@ package encryption
 import (
 	"bufio"
 	"io"
+	"strings"
 
 	"0chain.net/core/common"
 	"0chain.net/core/config"
@@ -66,3 +67,31 @@ func MiraclToHerumiPK(pk string) string {
 	}
 	return p.SerializeToHexStr()
 }
+
+// Converts signature 'sig' to format that the herumi/bls library likes.
+// zwallets are using MIRACL library which send a MIRACL signature not herumi
+// lib.
+//
+// If the 'sig' was not in MIRACL format, we just return the original sig.
+const miraclExampleSig = `(0d4dbad6d2586d5e01b6b7fbad77e4adfa81212c52b4a0b885e19c58e0944764,110061aa16d5ba36eef0ad4503be346908d3513c0a2aedfd0d2923411b420eca)`
+func MiraclToHerumiSig(sig string) string {
+	if len(sig) <= 2 {
+		return sig
+	}
+	if sig[0] != miraclExampleSig[0] {
+		return sig
+	}
+	withoutParens := sig[1: (len(sig)-1) ]
+	comma := strings.Index(withoutParens, ",")
+	if comma < 0 {
+		return "00"
+	}
+	n1 := withoutParens[0:comma]
+	n2 := withoutParens[(comma+1):]
+	var sign bls.Sign
+	err := sign.SetHexString("1 " + n1 + " " + n2)
+	if err != nil {
+		Logger.Error("MiraclToHerumiSig: " + err.Error())
+	}
+	return sign.SerializeToHexStr()
+}

code/go/0chain.net/core/encryption/keys_test.go

@@ -17,3 +17,21 @@ func TestMiraclToHerumiPK(t *testing.T) {
 	err := pk.DeserializeHexStr(pk1)
 	require.NoError(t, err)
 }
+
+func TestMiraclToHerumiSig(t *testing.T) {
+	miraclsig1 := `(0d4dbad6d2586d5e01b6b7fbad77e4adfa81212c52b4a0b885e19c58e0944764,110061aa16d5ba36eef0ad4503be346908d3513c0a2aedfd0d2923411b420eca)`
+	sig1 := MiraclToHerumiSig(miraclsig1)
+
+	require.EqualValues(t, sig1, "644794e0589ce185b8a0b4522c2181faade477adfbb7b6015e6d58d2d6ba4d0d")
+
+	// Assert DeserializeHexStr works on the output of MiraclToHerumiSig
+	var sig bls.Sign
+	err := sig.DeserializeHexStr(sig1)
+	require.NoError(t, err)
+
+	// Test that passing in normal herumi sig just gets back the original.
+	sig2 := MiraclToHerumiSig(sig1)
+	if sig1 != sig2 {
+		panic("Signatures should be the same.")
+	}
+}