RFC 6376, "DomainKeys Identified Mail (DKIM) Signatures", September 2011

Note: This RFC has been updated by RFC 8301, RFC 8463, RFC 8553, RFC 8616

Errata ID: 5252
Status: Verified
Type: Technical
Publication Format(s) : TEXT
Reported By: Alastair Houghton
Date Reported: 2018-02-02
Verifier Name: Barry Leiba
Date Verified: 2019-04-30

Section 3.7 says:

   More formally, pseudo-code for the signature algorithm is:

   body-hash    =  hash-alg (canon-body, l-param)
   data-hash    =  hash-alg (h-headers, D-SIG, body-hash)
   signature    =  sig-alg (d-domain, selector, data-hash)

   where:

   body-hash:  is the output from hashing the body, using hash-alg.

   hash-alg:   is the hashing algorithm specified in the "a" parameter.

   canon-body: is a canonicalized representation of the body, produced
               using the body algorithm specified in the "c" parameter,
               as defined in Section 3.4 and excluding the
               DKIM-Signature field.

   l-param:    is the length-of-body value of the "l" parameter.

   data-hash:  is the output from using the hash-alg algorithm, to hash
               the header including the DKIM-Signature header, and the
               body hash.

   h-headers:  is the list of headers to be signed, as specified in the
               "h" parameter.

   D-SIG:      is the canonicalized DKIM-Signature field itself without
               the signature value portion of the parameter, that is, an
               empty parameter value.

It should say:

   More formally, pseudo-code for the signature algorithm is:

   body-hash    =  hash-alg (canon-body, l-param)
   data-hash    =  hash-alg (h-headers, D-SIG)
   signature    =  sig-alg (d-domain, selector, data-hash)

   where:

   body-hash:  is the output from hashing the body, using hash-alg.

   hash-alg:   is the hashing algorithm specified in the "a" parameter.

   canon-body: is a canonicalized representation of the body, produced
               using the body algorithm specified in the "c" parameter,
               as defined in Section 3.4 and excluding the
               DKIM-Signature field.

   l-param:    is the length-of-body value of the "l" parameter.

   data-hash:  is the output from using the hash-alg algorithm, to hash
               the header including the DKIM-Signature header, and the
               body hash.

   h-headers:  is the list of headers to be signed, as specified in the
               "h" parameter.

   D-SIG:      is the canonicalized DKIM-Signature field itself without
               the signature value portion of the parameter, that is, an
               empty parameter value, with no trailing CRLF.

Notes:

data-hash does not include body-hash (body-hash is already included by virtue of the "bh=" tag in D-SIG). Also, D-SIG should not include the trailing CRLF, unlike the headers in h-headers.

Report New Errata