Docs: update DKIM standards info

(cherry picked from commit 27d0d9e6e002b2a9ea9a053e8163523592786ab5)
(cherry picked from commit 13912bf2bc166b324a73b4b5089defa5bb698ae6)
(cherry picked from commit 294f47fdbcbf5534a266d9abfcd1ccb873aff891)

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 20b08f6938e4db729c26736f4a0d3003bce92e4f..112c1efa20beeb8f2674bdfc1da9956a5b7cd9f1 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -39435,8 +39435,9 @@ Signers MUST use RSA keys of at least 1024 bits for all keys.
 Signers SHOULD use RSA keys of at least 2048 bits.
 .endd
 
 Signers SHOULD use RSA keys of at least 2048 bits.
 .endd
 

-Support for EC keys is being developed under
-&url(https://datatracker.ietf.org/doc/draft-ietf-dcrup-dkim-crypto/).
+.new
+EC keys for DKIM are defined by RFC 8463.
+.wen

 They are considerably smaller than RSA keys for equivalent protection.
 As they are a recent development, users should consider dual-signing
 (by setting a list of selectors, and an expansion for this option)
 They are considerably smaller than RSA keys for equivalent protection.
 As they are a recent development, users should consider dual-signing
 (by setting a list of selectors, and an expansion for this option)


@@ -39456,10 +39457,12 @@ openssl pkey -outform DER -pubout -in dkim_ed25519.private | tail -c +13 | base6
 certtool --load_privkey=dkim_ed25519.private --pubkey_info --outder | tail -c +13 | base64
 .endd
 
 certtool --load_privkey=dkim_ed25519.private --pubkey_info --outder | tail -c +13 | base64
 .endd
 

-Note that the format
-of Ed25519 keys in DNS has not yet been decided; this release supports
-both of the leading candidates at this time, a future release will
-probably drop support for whichever proposal loses.
+.new
+Exim also supports an alternate format
+of Ed25519 keys in DNS which was a candidate during development
+of the standard, but not adopted.
+A future release will probably drop that support.
+.wen

 
 .option dkim_hash smtp string&!! sha256
 Can be set to any one of the supported hash methods, which are:
 
 .option dkim_hash smtp string&!! sha256
 Can be set to any one of the supported hash methods, which are: