1 files changed, 65 insertions, 0 deletions
diff --git a/tests/hazmat/primitives/test_asym_utils.py b/tests/hazmat/primitives/test_asym_utils.py
new file mode 100644
index 00000000..bf55bad8
--- /dev/null
+++ b/tests/hazmat/primitives/test_asym_utils.py
@@ -0,0 +1,65 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import pytest
+
+from cryptography.hazmat.primitives.asymmetric.utils import (
+    decode_rfc6979_signature, encode_rfc6979_signature
+)
+
+
+def test_rfc6979_signature():
+    sig = encode_rfc6979_signature(1, 1)
+    assert sig == b"0\x06\x02\x01\x01\x02\x01\x01"
+    assert decode_rfc6979_signature(sig) == (1, 1)
+
+    r_s1 = (
+        1037234182290683143945502320610861668562885151617,
+        559776156650501990899426031439030258256861634312
+    )
+    sig2 = encode_rfc6979_signature(*r_s1)
+    assert sig2 == (
+        b'0-\x02\x15\x00\xb5\xaf0xg\xfb\x8bT9\x00\x13\xccg\x02\r\xdf\x1f,\x0b'
+        b'\x81\x02\x14b\r;"\xabP1D\x0c>5\xea\xb6\xf4\x81)\x8f\x9e\x9f\x08'
+    )
+    assert decode_rfc6979_signature(sig2) == r_s1
+
+    sig3 = encode_rfc6979_signature(0, 0)
+    assert sig3 == b"0\x06\x02\x01\x00\x02\x01\x00"
+    assert decode_rfc6979_signature(sig3) == (0, 0)
+
+    sig4 = encode_rfc6979_signature(-1, 0)
+    assert sig4 == b"0\x06\x02\x01\xFF\x02\x01\x00"
+    assert decode_rfc6979_signature(sig4) == (-1, 0)
+
+
+def test_encode_rfc6979_non_integer():
+    with pytest.raises(ValueError):
+        encode_rfc6979_signature("h", 3)
+
+    with pytest.raises(ValueError):
+        encode_rfc6979_signature("3", "2")
+
+    with pytest.raises(ValueError):
+        encode_rfc6979_signature(3, "h")
+
+    with pytest.raises(ValueError):
+        encode_rfc6979_signature(3.3, 1.2)
+
+    with pytest.raises(ValueError):
+        encode_rfc6979_signature("hello", "world")
+
+
+def test_decode_rfc6979_trailing_bytes():
+    with pytest.raises(ValueError):
+        decode_rfc6979_signature(b"0\x06\x02\x01\x01\x02\x01\x01\x00\x00\x00")
+
+
+def test_decode_rfc6979_invalid_asn1():
+    with pytest.raises(ValueError):
+        # This byte sequence has an invalid ASN.1 sequence length as well as
+        # an invalid integer length for the second integer.
+        decode_rfc6979_signature(b"0\x07\x02\x01\x01\x02\x02\x01")