Print DirName differently in SAN's

[StephenWall]

When printing SubjectAlternativeNames, print the details of DirName entries in a different format than GENERAL_NAME_print() to avoid parsing issues due to commas.

Fixes #20312

[bukka]

This is indeed better but I'm a bit worried about BC impact as it can break already the implementation parsing the current format. I know that openssl_parse_x509 docs note that it is deliberately not documented but considering that it has been like this for ages, it's quite possible that changes in it will break code so I'm not sure we should change it.

I was thinking about this in past and thought about introducing some extra flag after $short_names that would allow switching the format. We have got more use cases for it. I'm not sure if it's a great API so something like this might potentially need internals discussion / RFC.

[StephenWall]

I do have a different approach to SANs, which returns comprehensive info about the SAN in an easily parsed format. I asked on the internals list if I should create an RFC on this, or just post a pull request, and if it should be included in the x509 parse output, or in a new function call, but got no response.

Array
(
    [name] => ...
    ...
    [extensions] => Array
        (
            [subjectAltName] =>
                DNS:www.good.org,
                email:[email protected],
                IP Address:192.168.0.1,
                othername:<unsupported>,
                othername:SmtpUTF8Mailbox:[email protected],
                URI:sip:[email protected],
                DirName:/C=US/ST=CA/L=San Francisco/O=Example Company/OU=Example Company Unit/CN=Bob,
                Registered ID:1.2.3.4.5
        )

    [subjectAlternativeName] => Array
        (
            [0] => Array
                (
                    [type] => DNS
                    [value] => www.good.org
                )

            [1] => Array
                (
                    [type] => email
                    [value] => [email protected]
                )

            [2] => Array
                (
                    [type] => IP Address
                    [value] => 192.168.0.1
                )

            [3] => Array
                (
                    [type] => othername
                    [value] => Array
                        (
                            [1.3.6.1.5.5.7.8.7] => [email protected]
                        )
                )

            [4] => Array
                (
                    [type] => othername
                    [value] => Array
                        (
                            [1.3.6.1.5.5.7.8.9] => [email protected]
                        )
                )

            [5] => Array
                (
                    [type] => URI
                    [value] => sip:[email protected]
                )

            [6] => Array
                (
                    [type] => DirName
                    [value] => Array
                        (
                            [2.5.4.6] => US
                            [2.5.4.8] => CA
                            [2.5.4.7] => San Francisco
                            [2.5.4.10] => Example Company
                            [2.5.4.11] => Example Company Unit
                            [2.5.4.3] => Bob
                        )

                )

            [7] => Array
                (
                    [type] => Registered ID
                    [value] => 1.2.3.4.5
                )

        )```
(sorry for the length :)

[bukka]

Yeah I think subjectAlternativeName field could be acceptable and helpful for users.

[bukka]

About the process for merging, it works that if there are no objections from any core developer, features like this can be merged without RFC.

Sorry I was a bit busy with other stuff so didn't have time to replay to your email and do the reviews sooner. It might take me some time again to do the another round of reviews but it should be all fine to get to 8.6 unless there are some objections.

[StephenWall]

Would you like me to close out this pull, and create a new one with the "subjectAlternativeName" as I described above?