Re: Issue with parsing of forwarded messages with attachments and quotes in the subject

2017-05-02 Thread Giovanni Salvatore Fois 

On 05/02/2017 11:13 AM, Timo Sirainen wrote:

On 2 May 2017, at 11.21, Giovanni Salvatore Fois 
 wrote:


Hi all,
 at work we use Roundcube acting as a mail client for the  Dovecot Imap 
server.

In Roundube the messages are parsed through the Imap BODYSTRUCTURE command
If a message contains forwarded messages and attachments and some of the 
messages contains
a quote (") in the subject, then the resulting BODYSTRUCTURE appears to be 
malformed.
---
After some digging through the code of Dovecot, it seems to me that the problem 
is related to the function: imap_append_string_for_humans
defined at the line 120 of the file src/lib-imap/imap-quote.c  (dovecot sources 
v. 2.2.29)

Said function is supposed to return a quoted version of the input string while 
removing unwanted
characters from the input data.

But,  if I call it with a string containing quotes as argument (eg: I am a lazy 
" programmer)  in
the resulting output the quotes aren't escaped and the output string is not 
quoted.


It's then written as a literal, so it actually looks correct to me.



I have done some further analysis of my real world cases and the problem arises when the subject 
line contains also a closed parenthesis, as in:


I'm a really ) bad "message"


In that case, part of the bodystructure is rendered as:

("Mon, 27 Mar 2017 11:18:04 +" I'm a really ) bad "message" (("First Address" NIL "username" 
"domain.com"))(( "Second Address" NIL "othername" "otherdomain.com")) ... and so on ...


That lonely parenthesis confuses the parser and so the resulting structure is 
slightly messed up.

I'm pretty positive that I can overcome the issue working on the client side.

Thank you for your time and please keep going with the good job.

Best regards,
Giovanni S. Fois

Issue with parsing of forwarded messages with attachments and quotes in the subject

2017-05-02 Thread Giovanni Salvatore Fois 

Hi all,
  at work we use Roundcube acting as a mail client for the  Dovecot 
Imap server.

In Roundube the messages are parsed through the Imap BODYSTRUCTURE command
If a message contains forwarded messages and attachments and some of the 
messages contains
a quote (") in the subject, then the resulting BODYSTRUCTURE appears to be 
malformed.
---
After some digging through the code of Dovecot, it seems to me that the problem is related to the 
function: imap_append_string_for_humans

defined at the line 120 of the file src/lib-imap/imap-quote.c  (dovecot sources 
v. 2.2.29)

Said function is supposed to return a quoted version of the input string while 
removing unwanted
characters from the input data.

But,  if I call it with a string containing quotes as argument (eg: I am a lazy 
" programmer)  in
the resulting output the quotes aren't escaped and the output string is not 
quoted.


This is related to the stated issue through the function calls in:
part_write_body   [ defined at line 142 of imap-bodystructure.c ]
which calls imap_envelope_write [defined at line 46 of imap-envelope.c]
which finally calls imap_append_string_for_humans


Thank you for your time.

Best regards,
Giovanni S. Fois