docs+security: clarify the SafeBag format specification

Rename CertificateV2 => Certificate and EncryptedKeyBag => EncryptedKey

Change-Id: I47dca47ddd4542b5548061373e469bb386fa20bf
diff --git a/docs/specs/certificate.rst b/docs/specs/certificate.rst
index 9233b75..2808bc8 100644
--- a/docs/specs/certificate.rst
+++ b/docs/specs/certificate.rst
@@ -45,20 +45,20 @@
 
 .. code-block:: abnf
 
-    CertificateV2 = DATA-TYPE TLV-LENGTH
-                      Name     ; /<IdentityName>/KEY/<KeyId>/<IssuerId>/<Version>
-                      MetaInfo ; ContentType == KEY, FreshnessPeriod required
-                      CertificateV2Content
-                      CertificateV2SignatureInfo
-                      SignatureValue
+    Certificate = DATA-TYPE TLV-LENGTH
+                    Name     ; /<IdentityName>/KEY/<KeyId>/<IssuerId>/<Version>
+                    MetaInfo ; ContentType == KEY, FreshnessPeriod required
+                    CertificateContent
+                    CertificateSignatureInfo
+                    SignatureValue
 
-    CertificateV2Content = CONTENT-TYPE TLV-LENGTH SubjectPublicKeyInfo
+    CertificateContent = CONTENT-TYPE TLV-LENGTH SubjectPublicKeyInfo
 
-    CertificateV2SignatureInfo = SIGNATURE-INFO-TYPE TLV-LENGTH
+    CertificateSignatureInfo = SIGNATURE-INFO-TYPE TLV-LENGTH
                                    SignatureType
                                    KeyLocator
                                    ValidityPeriod
-                                   *CertificateV2Extension
+                                   *CertificateExtension
 
 
 Name
@@ -103,8 +103,8 @@
 Content
 -------
 
-The ``Content`` element of a certificate contains the actual bits of the public key, formatted
-as a DER-encoded `SubjectPublicKeyInfo <https://tools.ietf.org/html/rfc5280#section-4.1.2.7>`__
+The ``Content`` element of a certificate contains the actual bits of the public key, formatted as
+a DER-encoded `SubjectPublicKeyInfo <https://datatracker.ietf.org/doc/html/rfc5280#section-4.1.2.7>`__
 structure.
 
 SignatureInfo
@@ -176,7 +176,7 @@
 
 .. code-block:: abnf
 
-    CertificateV2Extension = AdditionalDescription
+    CertificateExtension = AdditionalDescription
 
     AdditionalDescription = ADDITIONAL-DESCRIPTION-TYPE TLV-LENGTH
                               1*DescriptionEntry
diff --git a/docs/specs/safe-bag.rst b/docs/specs/safe-bag.rst
index 6cc6773..04e3c4e 100644
--- a/docs/specs/safe-bag.rst
+++ b/docs/specs/safe-bag.rst
@@ -1,24 +1,24 @@
 SafeBag Format for Exported Credentials
 =======================================
 
-Sometimes, one may need to export credentials (e.g., certificate and private key) from
-one machine, and import them into another machine.  This requires a secured container for
-sensitive information.  We define **SafeBag**, which contains both an NDN certificate
-(:doc:`version 2.0 <certificate>`) and the corresponding private key, which is encrypted
-in `PKCS #8 format <https://tools.ietf.org/html/rfc5208>`_.
+Sometimes it may be necessary to export an identity's credentials (i.e., private key and
+associated certificate) from one machine and import them into another. This requires a
+secure container to carry the sensitive information. We define **SafeBag**, which contains
+an :doc:`NDN certificate </specs/certificate>` and the corresponding private key in encrypted
+form. The private key is formatted as a DER-encoded
+`EncryptedPrivateKeyInfo <https://datatracker.ietf.org/doc/html/rfc5208#section-6>`__
+structure as described in PKCS #8.
 
-The format of **SafeBag** is defined as:
+The TLV-based format of ``SafeBag`` is defined as follows:
 
 .. code-block:: abnf
 
     SafeBag = SAFE-BAG-TYPE TLV-LENGTH
-                CertificateV2
-                EncryptedKeyBag
+                Certificate
+                EncryptedKey
 
-    EncryptedKeyBag = ENCRYPTED-KEY-BAG-TYPE TLV-LENGTH
-                        *OCTET ; private key encrypted in PKCS #8 format
-
-All TLV-TYPE numbers are application specific:
+    EncryptedKey = ENCRYPTED-KEY-TYPE TLV-LENGTH
+                     *OCTET ; PKCS #8 EncryptedPrivateKeyInfo
 
 +---------------------------------------------+------------------+-----------------+
 | Type                                        | Assigned number  | Assigned number |
@@ -26,5 +26,5 @@
 +=============================================+==================+=================+
 | SafeBag                                     | 128              | 0x80            |
 +---------------------------------------------+------------------+-----------------+
-| EncryptedKeyBag                             | 129              | 0x81            |
+| EncryptedKey                                | 129              | 0x81            |
 +---------------------------------------------+------------------+-----------------+