On Thu, Apr 28, 2022 at 10:32 AM Ulrich Windl < ulrich.wi...@rz.uni-regensburg.de> wrote:
> >>> Mantas Mikulenas <graw...@gmail.com> schrieb am 27.04.2022 um 12:03 in > Nachricht > <capwny8xo0tu6edpjo538qygbj0komzo5icaojppc8kt4qz+...@mail.gmail.com>: > > On Wed, Apr 27, 2022 at 10:09 AM Ulrich Windl < > > ulrich.wi...@rz.uni-regensburg.de> wrote: > > > >> Hi! > >> > >> Having written an RFC 3164 compatible syslog daemon, I noticed that > systemd > >> created syslog messages with non-ASCII characters. > >> The problem is that a remote syslogd can hardly guess the correct > character > >> set (I'm using rsyslog to forward local messages to a remote server). > >> > >> Example of such message: > >> systemd-tmpfiles[3311]: [/usr/lib/tmpfiles.d/svnserve.conf:1] Line > >> references > >> path below legacy directory /var/run/, updating /var/run/svnserve → > >> /run/svnserve; please update the tmpfiles.d/ drop-in file accordingly. > >> > >> (The arrow is encoded as three bytes (\xe2\x86\x92)) > >> > >> RFC 5425 syslog messages require the use of a BOM (%xEF.BB.BF) at the > >> beginning of a message if the message used UTF-8: > >> > >> MSG = MSG-ANY / MSG-UTF8 > >> MSG-ANY = *OCTET ; not starting with BOM > >> MSG-UTF8 = BOM UTF-8-STRING > >> BOM = %xEF.BB.BF > >> > >> Wouldn't it make sense to add such a BOM for RFC 3164 syslog messages > also > >> if > >> non-ASCII (i.e.: UTF-8) encoded characters are used? > >> > > > > RFC 3164 over a local socket from journald to local rsyslogd? The local > > Actually I wasn't quite sure about the default config in SLES12. > It seems the flow is journald -> local rsyslogd -> remote syslogd > > > rsyslogd already knows if messages are UTF-8 because the system's $LANG > > (well, nl_langinfo) says so. And if rsyslog can't trust that for some > > reason (e.g. because a user might have a different locale), then > > systemd-journald won't be able to trust it either, so it won't know > whether > > it could add the BOM. > > How could a remote syslog server know what the locale on the sending system > is? > It's not remote, it's local. I'm talking about the one that's receiving messages from journald on the same machine. > > > > > RFC 3164 over the network to a remote server? Outside the scope for > > systemd, since it doesn't generate the network packets; your local > rsyslogd > > forwarder does. (Also, why RFC 3164 and not 5425?) > > If you look outside the world of systemd, about 99% of systems create the > RFC > 3164 type of messages. > Some may send non-ASCII too, however. > Still outside the scope of systemd. Systemd doesn't send RFC 3164 messages over the network, either. > > > > > Generally, if a message successfully decodes as UTF-8 then it's most > likely > > actual UTF-8 (and if UTF-8 decode fails then you fall back to ISO8859-1). > > Various old systems get away with this without needing a UTF-8 BOM. > > Yes, you can just output what you received, hoping the messages will be > presented correctly. > I't just like sending 8-bit E-Mmail without a coding system or charset in > the > past. > Which is not what I was saying, but sure, whatever. -- Mantas Mikulėnas
