Re: org-encrypt-entries is slow (was: org-crypt leaking data when encryption password is not entered twice (was: Please document the caching and its user options))

[Daniel Clemente <n142857@gmail.com>]

> > With that code I see something strange: I opened a file which had
> > encrypted :crypt: sections (never unencrypted), and after adding a
> > space somewhere else and saving, it asked me for an encryption
> > password. It shouldn't, since all sections are encrypted.
> > I also see „org-crypt: Re-encrypting all decrypted entries due to
> > auto-save“ asking me for the encryption password.
>
> Note that it may be asking about _different_ buffers, not just current.
> That's because auto-save-mode saves all the buffers, not just current :)
>

It would be good to know what buffer it is asking about; see
suggestion later below, about mentioning its name.
But I think it's already telling me which buffer it is, by moving the
point to the affected section, before asking the question.
It's the first section in the current file. And I can see that it's
actually encrypted.

I see it's trying to decrypt things (therefore it asks for the
password). It shouldn't, since I didn't modify any encrypted section.
I said „it asked me for an encryption password“ because the GPG prompt
confusingly uses the word „encryption“ („Passphrase for symmetric
encryption“), though it's actually asking for a decryption password.
It calls:

  org-decrypt-entry()
  (progn (org-decrypt-entry))
  (if (get-text-property (point) 'org-crypt-auto-encrypted) (progn
(org-decrypt-entry)))
  (while (not (eobp)) (if (get-text-property (point)
'org-crypt-auto-encrypted) (progn (org-decrypt-entry))) (goto-char
(next-single-char-property-change (point) 'org-crypt-auto-encrypted)))
  (save-restriction (widen) (goto-char (point-min)) (while (not
(eobp)) (if (get-text-property (point) 'org-crypt-auto-encrypted)
(progn (org-decrypt-entry))) (goto-char
(next-single-char-property-change (point)
'org-crypt-auto-encrypted))))
  (save-excursion (save-restriction (widen) (goto-char (point-min))
(while (not (eobp)) (if (get-text-property (point)
'org-crypt-auto-encrypted) (progn (org-decrypt-entry))) (goto-char
(next-single-char-property-change (point)
'org-crypt-auto-encrypted)))))
  (let ((modified-flag (buffer-modified-p))) (save-excursion
(save-restriction (widen) (goto-char (point-min)) (while (not (eobp))
(if (get-text-property (point) 'org-crypt-auto-encrypted) (progn
(org-decrypt-entry))) (goto-char (next-single-char-property-change
(point) 'org-crypt-auto-encrypted))))) (set-buffer-modified-p
modified-flag))
  org-crypt--decrypt-marked-entries()
  run-hooks(after-save-hook)
  basic-save-buffer(t)



> > But I tried removing all :crypt: tags (I renamed them to something
> > else), and saving a large file seems as slow as before. A few seconds
> > (often 5 seconds; sometimes it's just 2 or 3; this was the case before
> > too). Here's when it's 5, for 1 save:
>
> I think I fixed this now.
> May you try the latest version of the same branch?
>

This particular case in which there are no :crypt: tags is fast now,
thanks. In the same large file as before, saving is instantaneous
(well, the usual 100 to 200 ms).

          22   2%     - run-hook-with-args-until-success
          22   2%      - org-crypt--encrypt-and-mark-entries
          22   2%       - let
          22   2%        - condition-case
          22   2%         - unwind-protect
          22   2%          - org-encrypt-entries
          22   2%           - org-encrypt--map-items
          22   2%            - let*
          22   2%             - if
          22   2%              - or
          22   2%               - save-excursion
          22   2%                - save-restriction
          22   2%                   re-search-forward


> > I also see new problems (which would take me a long time to explain
> > since I don't understand the code or the settings), where:
> > - Org asks me for an encryption password even if there are no :crypt:
> > tags. I just changed the only :crypt: tag to a :nocrypt: tag and saved
>
> I cannot reproduce. May you create a small example file and explain how
> to trigger the problem you are seeing?

This is the text "abc" encrypted with password "abc". Use this file:

* hi                                                                  :nocrypt:
-----BEGIN PGP MESSAGE-----

jA0ECQMCVpS/qSoed5f/0joBYoIRWdgt/+PVQCsZh9sg176SdnvP2Wc8tH/CV1Rk
l2MjAh3Rk19Q2aP2EffpZ5CFeGELTMXCnCYv
=FNtI
-----END PGP MESSAGE-----

Open the file, add a space to the title and save it. The first time it
works (no questions asked) because there's no tag called :crypt:
Now change the :nocrypt: to :crypt: and save.  It asks for the
password. Press C-g to cancel.
Change again the tag to :nocrypt:. Save. It asks for the encryption
password; it shouldn't.
Add a space to the title, save, it keeps asking for the encryption
password, though there's no :crypt: section.


>
> > - Org spends around 20 seconds trying to save the file, in a loop,
> > reporting:  (error "org-crypt: Encryption failed.  Not saving the
> > buffer. Error: GPG error: \"Encrypt failed\", \"Canceled; Exit\"")
>
> This is curious, but I again have no clue. Maybe the new version of the
> branch works a bit better.
>

Since this error can happen because of a problem in a different buffer
(not the current one), would it be good to mention the file name in
that error message?

I didn't see this particular problem again. But I see others, which
are hard to report and reproduce. For instance I had an encrypted
section under a :crypt: header (I see „BEGIN PGP“ and hex codes), I
save, and saving *UNencrypts* the header before saving, without
asking. It should never decrypt when saving, but it does. This happens
with the same small example I posted above (but using the :crypt:
tag).