Russ,
Great work but I have two minor comments and a suggestion for new signed
attribute:
1) Sec 5, the last paragraph should read:
"This section is divided into six parts. The first part describes the
top-level type SignedData, the second part describes the
EncapsulatedContentInfo, the third part describes the per-signer
information type SignerInfo, and the fourth, fifth, and sixth parts
describe the message digest calculation, signature generation, and
signature validation processes, respectively."
2) Sec 5.2, the first should read:
"The actual content is represented in the type EncapsulatedContentInfo:"
3) Sec 11 should contain a new signed attribute as suggested in my previous
messages that binds particular Attribute Certificate(s) with a signed
content to convey the signer's privilege. It would read as follows:
"11.6 Signer Privileges
The signer-privilege attribute type specifies the attribute certificate
that must be considered to be bound with the ContentInfo value being signed
in signed-data and/or in a countersignature attribute. The
signer-privilege attribute helps in conveying the signer's privilege to the
verifier's application.
The signer-privilege attribute may be a signed attribute; it cannot be an
unsigned attribute, an authenticated attribute, or an unauthenticated
attribute.
The following object identifier identifies the signerPrivilege attribute type:
id-aa-signerPrivilege OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs9(9) smime(16) <TBD> }
Signer-privilege attribute values have ASN.1 type SignerPrivilege:
SignerPrivilege ::= IssuerSerial
IssuerSerial ::= SEQUENCE {
issuer GeneralNames,
serialNumber CertificateSerialNumber,
issuerUID UniqueIdentifier OPTIONAL }
Where the fields of IssuerSerial have the following meanings:
The issuer is the name of the Attribute Authority which created the
attribute certificate.
The serialNumber is the serial number that uniquely identifies the
attribute certificate.
The issuerUID may be used to identify the issuer of the attribute
certificate in instances where the issuer name is not sufficient. This may
be required because of the use of GeneralNames to identify the issuer of
the attribute certificate.
Note: The definition of IssuerSerial matches the one specified in the 1997
version of X.509 for an attribute certificate.
A signerPrivilege attribute can have multiple attribute values.
Until the use of attribute certificates gets better defined, the processing
of the signerPrivilege attribute should left to the verifier's application."
Francois Rousseau