So your login is based on cyrus-sasl libraries and mechanism PLAIN, the
mechanism PLAIN requires three arguments,<authz>\0<authc>\0<passwd>,
if no authorization is requested, the authentication string has to be
set twice and the whole string has to be base64 hashed. something like
this one:
Zm9vAGZvbwBiYXI=
just decode it, it is a proper PLAIN credentials string.
If you see a corrupted decoded string this is probably due to passing
only a fraction of the base64 string to the decoding software or the
characters are not UTF-8 based (which is a SHALL in RFC-4616). There is
a limitation of 255 octets to each of the three arguments, but your
string is not hitting this limitation.
Please check carefully smtp_sasl_password_maps file
-Dieter
Hello Dieter,
The decoded string is not corrupt. It show the username well. When I
decode the string the last characters are cut off. I have this setting
in main.cf: smtp_sasl_password_maps = hash:/etc/postfix/sasl_password
When I do a "postmap -s sasl_password" the exact and correct content of
sasl_password is given.
Rob