Re: [Orgmode] Re: [ANN] Org-babel integrated into Org-mode

[Eric Schulte]

Hi,

To add some concreteness to my suggestions I'm attaching to possible
patches.

The first introduces a global `org-confirm-babel-evaluate' variable
which defaults to t, meaning all code block evaluations will require
explicit confirmation from the user.

The second patch adds an `org-babel-disable:emacs-lisp' function which
can be called from a users configuration to ensure that *no* emacs-lisp
code blocks can be evaluated on the user's system.

Best -- Eric

>From 993dda2b88220a994422becdef11773986094ce6 Mon Sep 17 00:00:00 2001
From: Eric Schulte <address@hidden>
Date: Wed, 30 Jun 2010 12:25:22 -0700
Subject: [PATCH 1/2] babel: evaluation of code blocks now requires confirmation

* lisp/babel/ob.el (org-confirm-babel-evaluate): variable used to
  control evaluation of code blocks, default value it t, meaning all
  code block evaluation requires confirmation

  (org-babel-confirm-evaluate): function used to request confirmation
  of code block evaluation from the user

  (org-babel-execute-src-block-maybe): now requires explicit user
  confirmation before evaluating a code block

  (org-babel-open-src-block-result): now requires explicit user
  confirmation before evaluating a code block

* lisp/org.el (org-ctrl-c-ctrl-c): added documentation of code block
  evaluation behavior
---
 lisp/babel/ob.el |   76 +++++++++++++++++++++++++++++++++++++----------------
 lisp/org.el      |    7 ++++-
 2 files changed, 59 insertions(+), 24 deletions(-)

diff --git a/lisp/babel/ob.el b/lisp/babel/ob.el
index 6a42bcc..e2ffd67 100644
--- a/lisp/babel/ob.el
+++ b/lisp/babel/ob.el
@@ -61,6 +61,18 @@
 (declare-function org-babel-ref-variables "ob-ref" (params))
 (declare-function org-babel-ref-resolve-reference "ob-ref" (ref &optional 
params))
 
+(defcustom org-confirm-babel-evaluate t
+  "Require confirmation before interactively evaluating code
+blocks in Org-mode buffers.  The default value of this variable
+is t, meaning confirmation is required for any code block
+evaluation.  This variable can be set to nil to inhibit any
+future confirmation requests.
+
+Note disabling confirmation may result in accidental evaluation
+of potentially harmful code."
+  :group 'org-babel
+  :type 'boolean)
+
 (defvar org-babel-source-name-regexp
   "^[ \t]*#\\+\\(srcname\\|source\\|function\\):[ \t]*"
   "Regular expression used to match a source name line.")
@@ -134,6 +146,19 @@ added to the header-arguments-alist."
           (org-babel-parse-inline-src-block-match)
         nil))))
 
+(defun org-babel-confirm-evaluate (&optional info)
+  "Confirm that the user wishes to evaluate the code block
+defined by INFO.  This behavior can be suppressed by setting the
+value of `org-confirm-babel-evaluate' to nil, in which case all
+future interactive code block evaluations will proceed without
+any confirmation from the user.
+
+Note disabling confirmation may result in accidental evaluation
+of potentially harmful code."
+  (or (not org-confirm-babel-evaluate)
+      (yes-or-no-p (format "Evaluate this%scode on your system?"
+                          (if info (format " %s " (nth 0 info)) " ")))))
+
 ;;;###autoload
 (defun org-babel-execute-src-block-maybe ()
   "Detect if this is context for a org-babel src-block and if so
@@ -141,7 +166,10 @@ then run `org-babel-execute-src-block'."
   (interactive)
   (let ((info (org-babel-get-src-block-info)))
     (if info
-        (progn (org-babel-execute-src-block current-prefix-arg info) t) nil)))
+       (if (org-babel-confirm-evaluate info)
+           (progn (org-babel-execute-src-block current-prefix-arg info) t)
+         (error "evaluation aborted"))
+      nil)))
 
 (add-hook 'org-ctrl-c-ctrl-c-hook 'org-babel-execute-src-block-maybe)
 
@@ -379,28 +407,30 @@ argument RE-RUN the source-code block is evaluated even if
 results already exist."
   (interactive "P")
   (when (org-babel-get-src-block-info)
-    (save-excursion
-      ;; go to the results, if there aren't any then run the block
-      (goto-char (or (and (not re-run) (org-babel-where-is-src-block-result))
-                     (progn (org-babel-execute-src-block)
-                            (org-babel-where-is-src-block-result))))
-      (end-of-line 1)
-      (while (looking-at "[\n\r\t\f ]") (forward-char 1))
-      ;; open the results
-      (if (looking-at org-bracket-link-regexp)
-          ;; file results
-          (org-open-at-point)
-        (let ((results (org-babel-read-result)))
-          (flet ((echo-res (result)
-                           (if (stringp result) result (format "%S" result))))
-            (pop-to-buffer (get-buffer-create "org-babel-results"))
-            (delete-region (point-min) (point-max))
-            (if (listp results)
-                ;; table result
-                (insert (orgtbl-to-generic results '(:sep "\t" :fmt echo-res)))
-              ;; scalar result
-              (insert (echo-res results))))))
-      t)))
+    (if (org-babel-confirm-evaluate)
+       (save-excursion
+         ;; go to the results, if there aren't any then run the block
+         (goto-char (or (and (not re-run) 
(org-babel-where-is-src-block-result))
+                        (progn (org-babel-execute-src-block)
+                               (org-babel-where-is-src-block-result))))
+         (end-of-line 1)
+         (while (looking-at "[\n\r\t\f ]") (forward-char 1))
+         ;; open the results
+         (if (looking-at org-bracket-link-regexp)
+             ;; file results
+             (org-open-at-point)
+           (let ((results (org-babel-read-result)))
+             (flet ((echo-res (result)
+                              (if (stringp result) result (format "%S" 
result))))
+               (pop-to-buffer (get-buffer-create "org-babel-results"))
+               (delete-region (point-min) (point-max))
+               (if (listp results)
+                   ;; table result
+                   (insert (orgtbl-to-generic results '(:sep "\t" :fmt 
echo-res)))
+                 ;; scalar result
+                 (insert (echo-res results))))))
+         t)
+      (error "evaluation aborted"))))
 
 ;;;###autoload
 (defun org-babel-execute-buffer (&optional arg)
diff --git a/lisp/org.el b/lisp/org.el
index f2d9ade..22aaef8 100644
--- a/lisp/org.el
+++ b/lisp/org.el
@@ -17011,7 +17011,12 @@ This command does many different things, depending on 
context:
 - If the cursor is on a numbered item in a plain list, renumber the
   ordered list.
 
-- If the cursor is on a checkbox, toggle it."
+- If the cursor is on a checkbox, toggle it.
+
+- If the cursor is on a code block, evaluate it.  The variable
+  `org-confirm-babel-evaluate' can be used to control prompting
+  before code block evaluation, by default every code block
+  evaluation requires confirmation."
   (interactive "P")
   (let  ((org-enable-table-editor t))
     (cond
-- 
1.7.0.4

>From a7c699331e4a86d5779cecec22de0a297cd13d1c Mon Sep 17 00:00:00 2001
From: Eric Schulte <address@hidden>
Date: Wed, 30 Jun 2010 12:37:07 -0700
Subject: [PATCH 2/2] babel: added function for completely disabling emacs-lisp 
code block evaluation

* lisp/babel/langs/ob-emacs-lisp.el (org-babel-disable:emacs-lisp):
  added function for completely disabling emacs-lisp code block
  evaluation, after this function is called emacs lisp code blocks
  will be note evaluable by Babel unless the ob-emacs-lisp file is
  re-loaded
---
 lisp/babel/langs/ob-emacs-lisp.el |   11 +++++++++++
 1 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/lisp/babel/langs/ob-emacs-lisp.el 
b/lisp/babel/langs/ob-emacs-lisp.el
index 81ee22e..8ddb8c3 100644
--- a/lisp/babel/langs/ob-emacs-lisp.el
+++ b/lisp/babel/langs/ob-emacs-lisp.el
@@ -68,6 +68,17 @@
        (org-babel-pick-name (nth 4 processed-params) (cdr (assoc :colnames 
params)))
        (org-babel-pick-name (nth 5 processed-params) (cdr (assoc :rownames 
params)))))))
 
+(defun org-babel-disable:emacs-lisp ()
+  "This function can be used to disable evaluation of emacs-lisp
+code blocks.  Calling this function ensures that no emacs-lisp
+code blocks can be evaluated on your system unless
+`ob-emacs-lisp' is later explicitly loaded or required."
+  (interactive)
+  (defun org-babel-execute:emacs-lisp (body params)
+    (error "Emacs lisp evaluation is disabled."))
+  (defun org-babel-expand-body:emacs-lisp (body params &optional 
processed-params)
+    (error "Emacs lisp evaluation is disabled.")))
+
 (provide 'ob-emacs-lisp)
 
 ;; arch-tag: e9a3acca-dc84-472a-9f5a-23c35befbcd6
-- 
1.7.0.4

"Eric Schulte" <address@hidden> writes:

> Hi Carsten, Matt, Scott,
>
> Carsten Dominik <address@hidden> writes:
>
>> Hi Matt, hi Eric,
>>
>> Matt, thanks a lot for bringing this up.  This is indeed a very
>> important and serious issue.  We need to address it.  We need to
>> step back and reconsider this carefully.
>>
>> Don't get me wrong, I absolutely think that Org Babel should give
>> you enough rope to hang yourself.  But we have to make sure that
>> this will not happen to a happy and unsuspecting Org mode, or even
>> an unsuspecting Emacs user who by chance opens a file with extension
>> .org.
>>
>> I remember very well when  first realized that shell links could
>> really affect you badly.  It scared me.
>>
>> You main proposal was to make Org Babel an optional module.
>> This will not solve the problem fully, I think, because we also
>> don't want that people who turn it on automatically commit
>> to potentially dangerous operations.  There is a lot of good stuff
>> in Babel which has nothing to do with code evaluation.
>>
>> Here is what I propose (several items are similar to what Eric proposes)
>>
>> 1. A new variable org-turn-on-babel.  We can discuss the default.
>>    If it is nil, org-babel should not be loaded.
>>    A default of t would be fine with me if we implement other
>>    measures listed below.
>>
>
> This sounds like a good idea to me, and it should address Matt's desire
> for enabling minimal Org-mode installs.  I would like this to default to
> t, so that new users can try out Org-babel without overmuch effort.
>
>>
>> 2. As Eric proposes, a variable similar to org-confirm-shell-link-
>>    function
>>    This should by default query for confirmation on any org-babel
>>    code execution, and can be configured to shut up by people who know
>>    what they are doing.
>>
>
> Sounds good, I think this is a reasonable safety measure.
>
>>
>> 3. Not loading emacs lisp evaluation by default.
>>
>
> I would push back on this point.  Largely because we have now crossed
> the like to where it is impossible to play with a code block w/o first
> dropping down to your configuration files, and evaluating require
> statements.
>
>>
>> 4. A new key in the babel keymap for org-babel-execute-code-block,
>>    for example `C-c C-v e'.  This should be documented as the default
>>    key for this operation.
>>
>
> Hmm, I'm less enthusiastic about this point and point 5.  I really like
> how 'C-c C-c' naturally does whatever-I-want given the context in which
> it's called, and I wouldn't want to lose that intuitiveness.  Similarly
> 'C-c C-o' currently opens the results of a code block, I also find this
> very appealing as it allows for a uniform top-level interface across an
> Org-mode document, be it a code block or a link.
>
> Here are my reasons why I think leaving this keybinding is safe.
>
> 1) Unlike with shell/elisp links, the contents of code blocks is almost
>    always visible right under the user's point.  So it is less likely to
>    evaluate something w/o having any idea what you are evaluating.
>
> 2) Adding a protection variable (e.g. org-confirm-babel-eval) means that
>    the only users who could potentially evaluate a code block with a
>    slip of the fingers would be users who have explicitly said that they
>    want to be able to easily run code blocks without confirmation.
>
> 3) Emacs exposes a number of entry points into code evaluation.  M-!
>    allows users to run shell commands, C-M-x evaluate the elisp at
>    point, and these have not caused problems in the past.
>
>>
>> 5. Removing org-babel-execute-code-block from `C-c C-c'.  Inclusion
>>    should be optional.
>>
>> 6. A section in the manual on code execution and associated security
>>    risks in Org mode.  This is not only about babel, but also about
>>    org-eval, org-eval-light, shell links and elisp links.  I have meant
>>    to write this section for a long time and would be willing to
>>    draft it. We could then refer to this section from a couple of
>>    places in the docs, without cluttering the docs with disclaimers.
>>
>
> This sounds like a very good idea.  I'd be happy to help write such a
> section.
>
>>
>> The reason for 4 and 5 is that I believe Org-mode users are trained
>> to blindly press `C-c C-c' whenever they want to update something at
>> point.  Matt's example of a blog post about `rm -rf' is a very
>> realistic example for bad code being evaluated by mistake, not even
>> due to malicious cations.  I belive that a special key for this
>> action would gove a good measure of protection.
>>
>
> As I mentioned, I personally feel that an org-confirm-babel-eval
> variable is sufficient protection.  I think it's safe to assume that if
> a user has explicitly customized that variable, then they know what
> they're doing and trust themselves to execute code responsibly.  I think
> it's likely that the casual Org-babel user would never customize this
> variable, which seems to me entirely appropriate.
>
>>
>> This is what I think - please let me know if you think I am overdoing
>> it.
>>
>
> So to summarize, I think that the combination of (1), (2) and (6),
> should be sufficient to protect users from accidental code evaluation.
> Please let me know what you think, I am of course looking to compromise
> and I fully understand that the general consensus may be that we need
> more layers of protection.
>
> Best -- Eric
>
>>
>> - Carsten
>>
>>
>> On Jun 29, 2010, at 8:23 PM, Matt Lundin wrote:
>>
>>> Hi Eric,
>>>
>>> Thanks again for all the work that you, Dan, and Tom have put into
>>> org-babel. I'm glad to see it become part of org-mode!
>>>
>>> "Eric Schulte" <address@hidden> writes:
>>>
>>>> 2) Babel will now be loaded by default along with the rest of Org-
>>>> mode.
>>>>   This means that *everyone* currently using babel will need to
>>>> change
>>>>   their Emacs config and remove the (require 'org-babel-int) and/or
>>>>   (require 'org-babel) lines.
>>>
>>> I would like to request that org-babel be made an optional module. I
>>> ask
>>> this as someone who uses org-babel regularly. Here are my reasons:
>>>
>>>  - Org-babel adds rather specific and complex functionality to org-
>>> mode
>>>    that those who use it as a simple outliner and todo manager do not
>>>    require. (In other words, an option to turn it off might be nice
>>> for
>>>    those who are worried about "feature creep.")
>>>
>>>  - Org-babel increases the risk of accidentally executing malicious or
>>>    dangerous code when typing C-c C-c on a src block or exporting a
>>>    file. Perhaps users should activate it only after they understand
>>>    the risks.
>>>
>>>    + For instance, I might write a blog post warning about the dangers
>>>      of typing "rm -rf ~/". If I put this between #+begin_src sh
>>>      and #+end_src and unthinkingly hit C-c C-c, I would be in
>>> trouble.
>>>      I believe this is the reason for the variables
>>>      org-confirm-shell-link-function and
>>>      org-confirm-elisp-link-function.
>>>
>>>    + This is admitted a bit far-fetched as an example, as it would
>>>      require one to have loaded ob-sh.el. But since elisp execution is
>>>      activated by default, there remain opportunities for unwittingly
>>>      executing code that is meant for other purposes (e.g., warnings,
>>>      examples, etc.).
>>>
>>>>   Support for evaluating emacs-lisp code blocks is loaded by default.
>>>>   All other languages will need to be required explicitly.  To
>>>> conform
>>>>   to Emacs filename specifications all language require lines have
>>>> been
>>>>   shortened from e.g.
>>>>
>>>>   (require 'org-babel-sh)
>>>>
>>>>   to
>>>>
>>>>   (require 'ob-sh)
>>>
>>> When I run make clean && make && make install I find that the language
>>> directory is not installed. Does the langs directory require a manual
>>> installation?
>>>
>>> Also, with make install, the ob-* files are installed on the same
>>> level
>>> as the org-files, yet lines 108-114 in org.el indicate that they
>>> should
>>> be installed in a babel subdirectory.
>>>
>>> Thanks!
>>> Matt
>>>
>>> _______________________________________________
>>> Emacs-orgmode mailing list
>>> Please use `Reply All' to send replies to the list.
>>> address@hidden
>>> http://lists.gnu.org/mailman/listinfo/emacs-orgmode
>>
>> - Carsten