[Dovecot] Plugin issue with update from 2.0.19 to 2.1.17

[Timo Sirainen]

On 15.10.2013, at 23.33, Reinaldo Matukuma <ramatukuma at hotmail.com> wrote:

> Hello. Probably only Timo can help-me with this.
> 
> I have a self-made plugin based on the zlib plugin that i use to cryptograph the messages at inbox.
> 
> As a side-effect of the cryptography, my plugin changes the size of the message, but until 2.0.19 this works well with dovecot index and the W/S flags.
> 
> But now, i'm going to upgrade to 2.1.17 and now i have these messages on log at my test ambiance:
> 
> Oct 15 20:19:25 test dovecot: imap(reinaldo at exemplo.com.br): Error: Cached message size smaller than expected (367 < 529)
> Oct 15 20:19:25 test dovecot: imap(reinaldo at exemplo.com.br): Error: Maildir filename has wrong S value, renamed the file from /storage/test/messages/exemplo.com.br/reinaldo/Maildir/.Sent/cur/1381879158.M634385P5208.test,S=367,W=378:2,S to /storage/test/messages/exemplo.com.br/reinaldo/Maildir/.Sent/cur/1381879158.M634385P5208.test,S=529:2,S
> Oct 15 20:19:25 test dovecot: imap(reinaldo at exemplo.com.br): Error: Corrupted index cache file /storage/test/messages/exemplo.com.br/reinaldo/Maildir/.Sent/dovecot.index.cache: Broken physical size for mail UID 6

Is it intended that when decrypting messages you’ll get exactly the original message back? Or are you also modifying the message? Assuming there is no modification, you could take a look at how http://dovecot.org/patches/2.2/mail-filter.tar.gz does that without problems. Message modifications should also be possible with that code with small modifications. I’m not sure if that code works for v2.1.