This page is just to write about things I did probably providing useful information also for others. Topics are software, technical issues, ...

Most interesting:

• 20190131: Use data from any SSL client certificate field for Exim authentication process, read more

20190912 Regenerate Openpgp public key from private key:

Since a Gnupg update, the tool will refuse to perform decryption when using only the private key. There is technically no reason for this and gpg does not provide any easy option to regenerate or calculate the public key from the private key or ways to ignore the missing key. This article shows a hacky way to regenerate 4096 bit public keys from private keys using peculiarities of the Openpgp storage format. Read more...

20190131 Use data from any SSL client certificate field for Exim authentication process:

Exim may use some fields from SSL client certificates in the authentication procedure, e.g. mailAddress, but others are not supported. The x500UniqueIdentifier field is not understood, which could be used by Dovecot to force the login user name to be the one from the SSL certificate. To use x500UniqueIdentifier in Exim and Dovecot this QUITE HACKY workaround can be used. Read more...