lnwire: add length validation in NewSigFromRawSignature

2025-08-29 07:00:55 +02:00 · 2022-03-08 14:35:22 +08:00
parent 1eefa2863c
commit 19b2236570
2 changed files with 229 additions and 12 deletions
--- a/lnwire/signature_test.go
+++ b/lnwire/signature_test.go
@@ -7,6 +7,7 @@ import (

 	"github.com/btcsuite/btcd/btcec/v2"
 	"github.com/btcsuite/btcd/btcec/v2/ecdsa"
+	"github.com/stretchr/testify/require"
 )

 func TestSignatureSerializeDeserialize(t *testing.T) {
@@ -92,3 +93,182 @@ func TestSignatureSerializeDeserialize(t *testing.T) {
 	// the signature from ModNScalar values which don't allow setting a
 	// value larger than N (hence the name mod n).
 }
+
+var (
+	// signatures from bitcoin blockchain tx
+	// 0437cd7f8525ceed2324359c2d0ba26006d92d85.
+	normalSig = []byte{
+		0x30, 0x44, 0x02, 0x20,
+		// r value
+		0x4e, 0x45, 0xe1, 0x69, 0x32, 0xb8, 0xaf, 0x51,
+		0x49, 0x61, 0xa1, 0xd3, 0xa1, 0xa2, 0x5f, 0xdf,
+		0x3f, 0x4f, 0x77, 0x32, 0xe9, 0xd6, 0x24, 0xc6,
+		0xc6, 0x15, 0x48, 0xab, 0x5f, 0xb8, 0xcd, 0x41,
+
+		0x02, 0x20,
+		// s value
+		0x18, 0x15, 0x22, 0xec, 0x8e, 0xca, 0x07, 0xde,
+		0x48, 0x60, 0xa4, 0xac, 0xdd, 0x12, 0x90, 0x9d,
+		0x83, 0x1c, 0xc5, 0x6c, 0xbb, 0xac, 0x46, 0x22,
+		0x08, 0x22, 0x21, 0xa8, 0x76, 0x8d, 0x1d, 0x09,
+	}
+
+	// minimal length with 1 byte r and 1 byte s.
+	minSig = []byte{
+		0x30, 0x06, 0x02, 0x01, 0x00, 0x02, 0x01, 0x00,
+	}
+
+	// sig length is below 6.
+	smallLenSig = []byte{
+		0x30, 0x05, 0x02, 0x01, 0x00, 0x02, 0x01, 0x00,
+	}
+
+	// sig length is above 6.
+	largeLenSig = []byte{
+		0x30, 0x07, 0x02, 0x01, 0x00, 0x02, 0x01, 0x00,
+	}
+
+	// r length is 2.
+	largeRSig = []byte{
+		0x30, 0x06, 0x02, 0x02, 0x00, 0x02, 0x01, 0x00,
+	}
+
+	// r length is 0.
+	smallRSig = []byte{
+		0x30, 0x06, 0x02, 0x00, 0x00, 0x02, 0x01, 0x00,
+	}
+
+	// s length is 2.
+	largeSSig = []byte{
+		0x30, 0x06, 0x02, 0x01, 0x00, 0x02, 0x02, 0x00,
+	}
+
+	// s length is 0.
+	smallSSig = []byte{
+		0x30, 0x06, 0x02, 0x01, 0x00, 0x02, 0x00, 0x00,
+	}
+
+	// r length is 33.
+	missPaddingRSig = []byte{
+		0x30, 0x25, 0x02, 0x21,
+		// r value with a wrong padding.
+		0xff,
+		0x4e, 0x45, 0xe1, 0x69, 0x32, 0xb8, 0xaf, 0x51,
+		0x49, 0x61, 0xa1, 0xd3, 0xa1, 0xa2, 0x5f, 0xdf,
+		0x3f, 0x4f, 0x77, 0x32, 0xe9, 0xd6, 0x24, 0xc6,
+		0xc6, 0x15, 0x48, 0xab, 0x5f, 0xb8, 0xcd, 0x41,
+		// s value is 0.
+		0x02, 0x01, 0x00,
+	}
+
+	// s length is 33.
+	missPaddingSSig = []byte{
+		// r value is 0.
+		0x30, 0x25, 0x02, 0x01, 0x00,
+		0x02, 0x21,
+		// s value with a wrong padding.
+		0xff,
+		0x18, 0x15, 0x22, 0xec, 0x8e, 0xca, 0x07, 0xde,
+		0x48, 0x60, 0xa4, 0xac, 0xdd, 0x12, 0x90, 0x9d,
+		0x83, 0x1c, 0xc5, 0x6c, 0xbb, 0xac, 0x46, 0x22,
+		0x08, 0x22, 0x21, 0xa8, 0x76, 0x8d, 0x1d, 0x09,
+	}
+)
+
+func TestNewSigFromRawSignature(t *testing.T) {
+	t.Parallel()
+	testCases := []struct {
+		name        string
+		rawSig      []byte
+		expectedErr error
+		expectedSig Sig
+	}{
+		{
+			name:        "valid signature",
+			rawSig:      normalSig,
+			expectedErr: nil,
+			expectedSig: Sig{
+				// r value
+				0x4e, 0x45, 0xe1, 0x69, 0x32, 0xb8, 0xaf, 0x51,
+				0x49, 0x61, 0xa1, 0xd3, 0xa1, 0xa2, 0x5f, 0xdf,
+				0x3f, 0x4f, 0x77, 0x32, 0xe9, 0xd6, 0x24, 0xc6,
+				0xc6, 0x15, 0x48, 0xab, 0x5f, 0xb8, 0xcd, 0x41,
+				// s value
+				0x18, 0x15, 0x22, 0xec, 0x8e, 0xca, 0x07, 0xde,
+				0x48, 0x60, 0xa4, 0xac, 0xdd, 0x12, 0x90, 0x9d,
+				0x83, 0x1c, 0xc5, 0x6c, 0xbb, 0xac, 0x46, 0x22,
+				0x08, 0x22, 0x21, 0xa8, 0x76, 0x8d, 0x1d, 0x09,
+			},
+		},
+		{
+			name:        "minimal length signature",
+			rawSig:      minSig,
+			expectedErr: nil,
+			// NOTE: r and s are both 0x00 here.
+			expectedSig: Sig{},
+		},
+		{
+			name:        "signature length too short",
+			rawSig:      []byte{0x30},
+			expectedErr: errSigTooShort,
+			expectedSig: Sig{},
+		},
+		{
+			name:        "sig length too large",
+			rawSig:      largeLenSig,
+			expectedErr: errBadLength,
+			expectedSig: Sig{},
+		},
+		{
+			name:        "sig length too small",
+			rawSig:      smallLenSig,
+			expectedErr: errBadLength,
+			expectedSig: Sig{},
+		},
+		{
+			name:        "r length too large",
+			rawSig:      largeRSig,
+			expectedErr: errBadRLength,
+			expectedSig: Sig{},
+		},
+		{
+			name:        "r length too small",
+			rawSig:      smallRSig,
+			expectedErr: errBadRLength,
+			expectedSig: Sig{},
+		},
+		{
+			name:        "s length too large",
+			rawSig:      largeSSig,
+			expectedErr: errBadSLength,
+			expectedSig: Sig{},
+		},
+		{
+			name:        "s length too small",
+			rawSig:      smallSSig,
+			expectedErr: errBadSLength,
+			expectedSig: Sig{},
+		},
+		{
+			name:        "missing padding in r",
+			rawSig:      missPaddingRSig,
+			expectedErr: errRTooLong,
+			expectedSig: Sig{},
+		},
+		{
+			name:        "missing padding in s",
+			rawSig:      missPaddingSSig,
+			expectedErr: errSTooLong,
+			expectedSig: Sig{},
+		},
+	}
+
+	for _, tc := range testCases {
+		tc := tc
+		t.Run(tc.name, func(t *testing.T) {
+			result, err := NewSigFromRawSignature(tc.rawSig)
+			require.Equal(t, tc.expectedErr, err)
+			require.Equal(t, tc.expectedSig, result)
+		})
+	}
+}