Update documentation for NoDigestInfo

Author: jahkosha

docs/hazmat/primitives/asymmetric/rsa.rst

@@ -784,9 +784,10 @@ Key interfaces
         ``algorithm`` parameters must match the ones used when the signature
         was created for the recovery to succeed.
 
-        The ``algorithm`` parameter can also be set to ``None`` to recover all
+        The ``algorithm`` parameter can also be set to ``NoDigestInfo`` to recover all
         the data present in the signature, without regard to its format or the
-        hash algorithm used for its creation.
+        hash algorithm used for its creation. (Note that setting ``algorithm`` to ``None`
+        is deprecated and have the same semantic as setting ``NoDigestInfo``.)
 
         For
         :class:`~cryptography.hazmat.primitives.asymmetric.padding.PKCS1v15`

docs/hazmat/primitives/asymmetric/utils.rst

@@ -29,6 +29,19 @@ Asymmetric Utilities
 
     :return bytes: The encoded signature.
 
+.. class:: NoDigestInfo()
+
+    .. versionadded:: 47.0
+
+    Use a non-standard RSA signature formats where the PKCS #1-padded data is without DigestInfo.
+
+    ``NoDigestInfo`` can be passed as the ``algorithm`` in the RSA
+    :meth:`~cryptography.hazmat.primitives.asymmetric.rsa.RSAPrivateKey.sign`,
+    :meth:`~cryptography.hazmat.primitives.asymmetric.rsa.RSAPublicKey.verify`
+    and
+    :meth:`~cryptography.hazmat.primitives.asymmetric.rsa.RSAPublicKey.recover_data_from_signature`
+    methods.
+
 .. class:: Prehashed(algorithm)
 
     .. versionadded:: 1.6