update doc language
diff --git a/docs/x509.rst b/docs/x509.rst
index 39df4a0..afc9620 100644
--- a/docs/x509.rst
+++ b/docs/x509.rst
@@ -460,7 +460,7 @@
:type: bool
- This is asserted when the subject public key is used for verifying
+ This purpose is set to true when the subject public key is used for verifying
digital signatures, other than signatures on certificates
(``key_cert_sign``) and CRLs (``crl_sign``).
@@ -468,7 +468,7 @@
:type: bool
- This is asserted when the subject public key is used for verifying
+ This purpose is set to true when the subject public key is used for verifying
digital signatures, other than signatures on certificates
(``key_cert_sign``) and CRLs (``crl_sign``). It is used to provide a
non-repudiation service that protects against the signing entity
@@ -481,48 +481,48 @@
:type: bool
- This is asserted when the subject public key is used for enciphering
- private or secret keys.
+ This purpose is set to true when the subject public key is used for
+ enciphering private or secret keys.
.. attribute:: data_encipherment
:type: bool
- This is asserted when the subject public key is used for directly
- enciphering raw user data without the use of an intermediate symmetric
- cipher.
+ This purpose is set to true when the subject public key is used for
+ directly enciphering raw user data without the use of an intermediate
+ symmetric cipher.
.. attribute:: key_agreement
:type: bool
- This is asserted when the subject public key is used for key agreement.
- For example, when a Diffie-Hellman key is to be used for key
- management, then this bit is set.
+ This purpose is set to true when the subject public key is used for key
+ agreement. For example, when a Diffie-Hellman key is to be used for
+ key management, then this purpose is set to true.
.. attribute:: key_cert_sign
:type: bool
- This is asserted when the subject public key is used for verifying
- signatures on public key certificates. If this bit is asserted then
- ``ca`` must be true in the :class:`BasicConstraints` extension.
+ This purpose is set to true when the subject public key is used for
+ verifying signatures on public key certificates. If this purpose is set
+ to true then ``ca`` must be true in the :class:`BasicConstraints`
+ extension.
.. attribute:: crl_sign
:type: bool
- This is asserted when the subject public key is used for verifying
- signatures on certificate revocation lists.
+ This purpose is set to true when the subject public key is used for
+ verifying signatures on certificate revocation lists.
.. attribute:: encipher_only
:type: bool
- The meaning of this bit is undefined in the absence of the
- ``key_agreement`` bit. When this bit is asserted and the
- ``key_agreement`` bit is also set, the subject public key may be
- used only for enciphering data while performing key agreement.
+ When this purposes is set to true and the ``key_agreement`` purpose is
+ also set, the subject public key may be used only for enciphering data
+ while performing key agreement.
:raises ValueError: This is raised if accessed when ``key_agreement``
is false.
@@ -531,10 +531,9 @@
:type: bool
- The meaning of this bit is undefined in the absence of the
- ``key_agreement`` bit. When this bit is asserted and the
- ``key_agreement`` bit is also set, the subject public key may be
- used only for deciphering data while performing key agreement.
+ When this purposes is set to true and the ``key_agreement`` purpose is
+ also set, the subject public key may be used only for deciphering data
+ while performing key agreement.
:raises ValueError: This is raised if accessed when ``key_agreement``
is false.