RE: Who has tried some or all of the S/MIME examples?

["Blake Ramsdell" <[e-mail]>]

> -----Original Message-----
> From: Jim Schaad [mailto:[e-mail]] 
> Sent: Wednesday, May 07, 2003 2:13 PM
> To: 'Blake Ramsdell'; 'Paul Hoffman / IMC'; 
> [e-mail]; [e-mail]
> Subject: RE: Who has tried some or all of the S/MIME examples?
> 
> 5.1.bin - failed
> 	1.  signatureAlgorithm is 1.2.840.10040.4.1 not
> 1.2.840.10040.4.3

From RFC3370, section 3.1:

   The algorithm identifier for DSA with SHA-1 signature values is:

      id-dsa-with-sha1 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
          us(840) x9-57 (10040) x9cm(4) 3 }

   When the id-dsa-with-sha1 algorithm identifier is used, the
   AlgorithmIdentifier parameters field MUST be absent.


From RFC2630, section 12.2.1:

   The DSA signature algorithm is defined in FIPS Pub 186 [DSS].  DSA is
   always used with the SHA-1 message digest algorithm.  The algorithm
   identifier for DSA is:

      id-dsa-with-sha1 OBJECT IDENTIFIER ::=  { iso(1) member-body(2)
          us(840) x9-57 (10040) x9cm(4) 3 }

   The AlgorithmIdentifier parameters field must not be present.


From RFC2633, section 2.2:

   Sending and receiving agents MUST support id-dsa defined in [DSS].
   The algorithm parameters MUST be absent (not encoded as NULL).


From RFC2633, Appendix A:

-- id-dsa OBJECT IDENTIFIER ::=
--    {iso(1) member-body(2) us(840) x9-57(10040) x9cm(4) 1 }


From rfc2633bis-03:

Receiving agents MUST support id-dsa defined in [CMSALG]. The
algorithm parameters MUST be absent (not encoded as NULL). Receiving
agents MUST support rsaEncryption, defined in [CMSALG].


From RFC3370, section 3.1:

      id-dsa OBJECT IDENTIFIER ::= { iso(1) member-body(2)
          us(840) x9-57 (10040) x9cm(4) 1 }


So the bottom line is that CMS says one thing (id-dsa-with-sha1), and
MSG says something else (id-dsa).  Consensus welcome.  We went round and
round about this at one point, due to the use of the rsaEncryption value
vs. the use of the sha-1WithRSAEncryption value.

Recommend accept both, emit id-dsa-with-sha1, change the samples to use
id-dsa-with-sha1 and changing rfc2633bis to say:


2.2 SignatureAlgorithmIdentifier

Receiving agents MUST support id-dsa-with-sha1 defined in [CMSALG]. The
algorithm parameters MUST be absent (not encoded as NULL). Receiving
agents MUST support rsaEncryption, defined in [CMSALG].

Sending agents MUST support either id-dsa-with-sha1 or rsaEncryption.

Note that S/MIME v3 clients might only implement signing or signature
verification using id-dsa-with-sha1, and might also use id-dsa as an
AlgorithmIdentifier in this field. Receiving clients SHOULD recognize
id-dsa as equivalent to id-dsa-with-sha1, and sending clients MUST use
id-dsa-with-sha1 if using that algorithm. Also note that S/MIME v2
clients are only capable of verifying digital signatures using the
rsaEncryption algorithm.

Blake