Bug 305171

Summary:	PGP/MIME signatures are invalid when text/plain; charset="us-ascii" is used
Product:	[Applications] kmail2	Reporter:	Hauke Laging <hauke>
Component:	crypto	Assignee:	kdepim bugs <kdepim-bugs>
Status:	RESOLVED WAITINGFORINFO
Severity:	major	CC:	montel, sknauss
Priority:	NOR
Version:	4.7
Target Milestone:	---
Platform:	openSUSE
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	mail with bad signature, saved from Thunderbird to a file

Description Hauke Laging 2012-08-15 00:06:39 UTC

Since KMail2 nearly all (more than 90%) of my email signatures are shown as invalid by other mail clients. I tried to understand which software is buggy by reading the rfc but I am still not sure. Most probably it is KMail2. KMail2 shows these signatures as correct.

The problem seems to be a missing newline. The MIME seperator is placed directly after my last signature line:

########################
PGP: D44C 6A5B 71B0 427C CED3 025C BD7D 6D27 ECCB 5814
--nextPart20694277.1dnrQtI15C
########################

In earlier versions of KMail (and in Thunderbird) there was en empty line in between:
########################
PGP: D44C 6A5B 71B0 427C CED3 025C BD7D 6D27 ECCB 5814

--nextPart3343035.S6mqRQsH14
########################

The signature is not completely wrong. If I save the mail as a file, convert it to DOS newline and add a newline to the end of the data block then I can verify the signature by gpg. So it is obvously just a formatting problem.

It seems not to make a difference whether the signature text ends with a newline.

Reproducible: Always

Steps to Reproduce:
1. Just send a signed email in PGP/MIME format.

Actual Results:  
Signature is not recognized by other mail clients.

Expected Results:  
A compatible signature (or rather: compatible MIME formatting of it).

Comment 1 Laurent Montel 2012-08-15 10:57:22 UTC

Sorry I can't success to test it.
How do you create PGP/MIME ?

I never success to have line as 
"########################
 PGP:
...
"
So I don't know how to configure/test it

Comment 2 Hauke Laging 2012-08-16 01:38:39 UTC

Embarrassing... but I have to correct some of my statements and guesses.

Meanwhile I have found the difference between the emails with valid signatures and those with invalid ones:

Content-Transfer-Encoding: 7Bit
Content-Type: text/plain; charset="us-ascii"

That's the problem. All emails with this encoding have invalid signatures. The problem has nothing to do with the newlines.

The sometimes "missing" newlines between the text signature and the MIME seperator are due to different identities I used for composing the emails. Of the two text signatures of those identities only one had a trailing newline. This effect was due to the change from KMail to KMail2 (because KMail2 killed the KMail configuration and I forgot the newline when restoring the identities manually).

Both identities (with and without trailing newline) can create valid and invalid signatures. That just depends on it whether non-ASCII characters occur in the message.

Comment 3 Myriam Schweingruber 2012-08-18 09:10:00 UTC

Hauke: which exact Kmail version is this about? Please set the version field.

Comment 4 Hauke Laging 2012-08-18 13:05:53 UTC

(In reply to comment #3)
> Hauke: which exact Kmail version is this about? Please set the version field.

It is 4.7.2 (the current openSUSE version). Now I can set 4.7. Funny, IIRC that value was not available when I opened the bug.

Comment 5 Sandro Knauß 2013-04-12 23:10:13 UTC

Can you give a text, that you entered into kmail, that has an invalid signature?
Can you pease give kmail 4.10.2 a try? There are some improments with CTE entered kmail.

Comment 6 Hauke Laging 2013-04-12 23:53:06 UTC

Created attachment 78849 [details]
mail with bad signature, saved from Thunderbird to a file

For reproducing the bug.

Comment 7 Hauke Laging 2013-04-12 23:55:17 UTC

(In reply to comment #5)
> Can you give a text, that you entered into kmail, that has an invalid
> signature?

I attach a mail I sent which is shown as badly signed in Thunderbird.

> Can you pease give kmail 4.10.2 a try? There are some improments with CTE
> entered kmail.

I just noticed that it seems to work in KMail/4.8.5 already. At least it's shown correctly by Thunderbird/Enigmail (which shows older mails as badly signed).

Comment 8 Hauke Laging 2014-01-04 05:17:35 UTC

Has been fixed (I don't know in which version, though).