diff --git a/signature_test.go b/signature_test.go
index a138a648..78cc47e5 100644
--- a/signature_test.go
+++ b/signature_test.go
@@ -31,6 +31,115 @@ var signatureTests = []signatureTest{
 		},
 		isValid: true,
 	},
+	signatureTest{
+		name: "empty.",
+		sig: []byte{},
+		isValid: false,
+	},
+	signatureTest{
+		name: "bad magic.",
+		sig: []byte{0x31, 0x44, 0x02, 0x20, 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, 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, 0x01,
+		},
+		isValid: false,
+	},
+	signatureTest{
+		name: "bad 1st int marker magic.",
+		sig: []byte{0x30, 0x44, 0x03, 0x20, 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, 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, 0x01,
+		},
+		isValid: false,
+	},
+	signatureTest{
+		name: "bad 2nd int marker.",
+		sig: []byte{0x30, 0x44, 0x02, 0x20, 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, 0x03, 0x20, 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, 0x01,
+		},
+		isValid: false,
+	},
+	signatureTest{
+		name: "short len",
+		sig: []byte{0x30, 0x43, 0x02, 0x20, 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, 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, 0x01,
+		},
+		isValid: false,
+	},
+	signatureTest{
+		name: "long len",
+		sig: []byte{0x30, 0x45, 0x02, 0x20, 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, 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, 0x01,
+		},
+		isValid: false,
+	},
+	signatureTest{
+		name: "long X",
+		sig: []byte{0x30, 0x44, 0x02, 0x42, 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, 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, 0x01,
+		},
+		isValid: false,
+	},
+	signatureTest{
+		name: "long Y",
+		sig: []byte{0x30, 0x44, 0x02, 0x20, 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, 0x21, 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, 0x01,
+		},
+		isValid: false,
+	},
+	signatureTest{
+		name: "short Y",
+		sig: []byte{0x30, 0x44, 0x02, 0x20, 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, 0x19, 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, 0x01,
+		},
+		isValid: false,
+	},
 }
 
 func TestSignatures(t *testing.T) {