RFC 2617 vs. 2831 md5-sess

Good news first, RFC 4590bis (approved, still waiting for its number) will fix the Digest-MD5 examples in RFC 4590. I've updated the MD5 test suite using the fixed examples.

While I was at it I've also updated the RFC 3797 code to work for the NOMCOM 2007 case. The entropy limit 30 was too restrictive, 38 is good enough for MD5, 10^38 < 2^128.

Now the bad news, the issue with two md5-sess examples in draft smith-sipping-auth-examples might be in fact precisely what RFC 2617 says, as reported in a semi-official erratum. If that's correct the md5-sess in RFC 2831 would be different. Hopefully draft melnikov-digest-to-historic will shed some light on this before it moves RFC 2831 to historic. For more about this see the IETF SASL WG mailing list.

For now the MD5 test suite still uses only the binary x2c(HA1) form instead of the hex. HA1 form in its md5-sess calculation.

HTML PUBLIC "-//IETF//DTD HTML i18n//EN"

Admittedly RFC 2070 is old, and its status is historic. But it was the first HTML specification with I18N based on UNICODE, and the last HTML specification published by the IETF.

So far its DTD had to be extracted manually from the RFC, now IANA hosts an official master copy with the public identifier urn:ietf:params:xml:pi:-:IETF:DTD+HTML+i18N:EN. The urn:ietf:params:xml:pi registry was created by RFC 3688 for DTDs developed by the IETF. Of course HTML i18n is still SGML, not XML, but its DTD is now the first registered IETF DTD.

If you have old HTML i18n documents you can use an URL of this DTD as system identifier like this:

<DOCTYPE HTML PUBLIC "-//IETF//DTD HTML i18n//EN" "http://www.iana.org/assignments/xml-registry/publicid/html2070.dtd">