Zulip attempts to validate that the regular expressions that admins
enter for linkifiers are well-formatted, and only contain a specific
subset of regex grammar. The process of checking these
properties (via a regex!) can cause denial-of-service via
backtracking.
Furthermore, this validation itself does not prevent the creation of
linkifiers which themselves cause denial-of-service when they are
executed. As the validator accepts literally anything inside of a
`(?P<word>...)` block, any quadratic backtracking expression can be
hidden therein.
Switch user-provided linkifier patterns to be matched in the Markdown
processor by the `re2` library, which is guaranteed constant-time.
This somewhat limits the possible features of the regular
expression (notably, look-head and -behind, and back-references);
however, these features had never been advertised as working in the
context of linkifiers.
A migration removes any existing linkifiers which would not function
under re2, after printing them for posterity during the upgrade; they
are unlikely to be common, and are impossible to fix automatically.
The denial-of-service in the linkifier validator was discovered by
@erik-krogh and @yoff, as GHSL-2021-118.
This fixes the issue where 'None' would appear in the rendered
html in case of a missing tab display_name. Now,
'test-help-documentation' will fail in case of any tab display_name
being missing.
In case of a tab_section with no tabs, currently a single tab with
the name 'null_tab' gets added. Added the display name 'None' for
'null_tab', to keep in line with the existing behaviour.
Fixes#19822
Recently, we discovered that our settings_tab/relative Markdown
directives didn't work when they were in a macro that was included
in another Markdown file. Note that without this commit, the
/help/create-your-organization-profile page is broken. This commit
changes the respective priorities of these two extensions such that
these directives are rendered *after* the macro is included in
another file.
Thanks to Alya Abbott for reporting this bug!
All of our custom Markdown extensions have priorities that govern
the order in which the preprocessors will be run. It is more
convenient to have these all in one file so that you can easily
discern the order at first glance.
Thanks to Alya Abbott for reporting the bug that led to this
refactoring!
This check was copied from upstream python-markdown's "safe mode"
before they removed that feature. The upstream history is that they
introduced this check in
2db5d1c8e4,
which was not a complete security check, and then added the
immediately following check (with an allowlist of schemes) in
0b4ffbb60e.
Their first, incomplete check provides no security benefit and makes
the code hard to reason about, so we remove it.
This adds the X-Smokescreen-Role header to proxy connections, to track
usage from various codepaths, and enforces a timeout. Timeouts were
kept consistent with their previous values, or set to 5s if they had
none previously.
This commits removes some unnecessary checks for `self.md.zulip_message`,
which were put there historically, as earlier we used to add the additional
properties like mentions_user_ids, alert_words, etc. to Message dict
only. These were later moved to MessageRenderingResult class in commit
75cea329b but the checks weren't removed.
This is important because while rendering the messages imported from
other chat tools (like Rocket.Chat), the Message dict is not passed to
the markdown, due to which the checks for `self.md.zerver_message` fails
and hence, things like user mentions, stream/topic mentions are not
rendered in the imported messages properly.
These changes are all independent of each other; I just didn’t feel
like making dozens of commits for them.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
This way we can stop reading as soon as we get to the body. Also,
send an Accept header, check that the request was actually successful,
use lxml.etree.iterparse instead of a broken hand-rolled state
machine, and support XHTML, all for negative 28 lines of code.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
This reverts commit 1965584eec.
This syntax has a bad interaction with table syntax and needs to be
rethought.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
This is more efficient than get_lexer_by_name, since we don’t need to
instantiate the class just to get its name.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
The absence of __init__.py was preventing mypy from following any of
the zerver.openapi imports. These errors were being silenced by
ignore_missing_imports.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
As we have changed the tab selector above from "Settings" to "Personal
settings", we can simply change "Your bots" to "Bots" as "Bots" is
clear enough given the personal settings context.
We also need to update the API documentation for bots accordingly.
This commit fixes the documentation of settings as we have
replaced "Your account" section into two new sections -
"Profile" and "Account & privacy".
This commit also fixes a comment in the test for settings
documentation in test_middleware.py.
This adds a new class called MessageRenderingResult to contain the
additional properties we added to the Message object (like alert_words)
as well as the rendered content to ensure typesafe reference. No
behavioral change is made except changes in typing.
This is a preparatory change for adding django-stubs to the backend.
Related: #18777
Currently, the message that no parameters are accepted by
the endpoint is displayed if there are no parameters in
OpenAPI data, but it is possible that information is
encoded in x-parameter-description (example in upload-file
endpoint), and we want to display that information rather
than the message.
Added an if condition to check the same.
The headings for return values were currently hardcoded
in cases where they occur, but they can be rendered directly
in the markdown extension if the return values exist.
This should help with #17425, where messages with lots of LaTeX are
lost, due to the large expansion factor.
This isn't a total fix for this - large messages with lots of LaTeX
can still end up larger than 1MB, and rendering could timeout, but
this fix should help significantly.
1MB is still small enough that I don't expect we'll run into any DOS
problems - my testing didn't show any problems rendering messages that
contain ~1MB of LaTeX.
This will offer users who are self-hosting to adjust
this value. Moreover, this will help to reduce the
overall time taken to test `test_markdown.py` (since
this can be now overridden with `override_settings`
Django decorator).
This is done as a prep commit for #18641.
?dl=1 causes Dropbox to send Content-Type: application/binary, which
can’t be interpreted by Camo. Use ?raw=1 instead.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Prior to this, we only supported direct mention to
the user groups. This commit extends that support
to silent mention for the user groups.
A related test case is also added.
Fixes: #11711.
Earlier, USER_GROUP_MENTIONS_RE was:
r"(?<![^\s\'\"\(,:<])@(\*[^\*]+\*)"
For the syntax: *foo*, this was unnecessarily capturing it as
*foo* and the extraction of `foo` was done using another helper
function: `extract_user_group`.
This is now changed as:
r"(?<![^\s\'\"\(,:<])@(\*(?P<match>[^\*]+)\*)"
and extraction of `foo` can be done just by using the named capture
group `match`.
This change also helps to simplify its related code path.
Earlier, MENTIONS_RE was:
r"(?<![^\s\'\"\(,:<])@(?P<silent>_?)(?P<match>\*\*[^\*]+\*\*)"
For the syntax: **foo**, this was unnecessarily capturing it as
**foo** and adding extra operation for the extraction of `foo`.
This is now changed as:
r"(?<![^\s\'\"\(,:<])@(?P<silent>_?)(\*\*(?P<match>[^\*]+)\*\*)"
and extraction of `foo` can be done just by using the named capture
group `match`.
This change also helps to simplify its related code path.
Following the convention, we use uppercase for
regex. Also, `user_group_mentions` is given a
conventional name ending with `*_RE`: `USER_GROUP_MENTIONS_RE`.
Also link to it from the API documentation page,
other help pages, and the confirmation dialog for
muting a user.
With substantial edits by tabbott and alya.
A message containing wildcard mention when quoted (which
is turned into a silent mention) or message with silent
wildcard mention notifies the users by sending desktop,
sound, and missed message email notifications. This
is clearly a bug which is fixed by this commit.
Fixes: #18354.
* Move the extended documentation of code blocks to a separate page.
* Merge "code playgrounds" documentation to be a section of that page.
* Document copy widget on code blocks.
* This commit changes how we refer to "```python" type syntax for code
blocks. Instead of being called a syntax highlighting label, this is
now referred to as a "language tag", since it serves both syntax
highlighting and playgrounds.
* Remap all the links.
* Advertise this new page in various places that previously did not have a link.
Linked the Help Center document in places like
- zulip.yaml (/events, /register/, realm/playgrounds,
/realm/playgrounds/{playground_id})
- /help/format-your-message-using-markdown (Linked to make
users reading the markdown code block style, aware of this
feature)
- /templates/settings/playground_settings_admin.hbs (Linked
as a reference to read more about playgrounds before
configuring one)
Also showcase the feature on /features and /for/open-source.
Requesting external images is a privacy risk, so route all external
images through Camo.
Tweaked by tabbott for better test coverage, more comments, and to fix
bugs.
This logic likely never ran due to a combination of bugs.
* Running `maybe_update_markdown_engines` unconditionally meant that
`if md_engine_key in md_engines` was likely always true.
* Introduced in 65838bb: DEFAULT_MARKDOWN_KEY could never be in
md_engines, so should we have ever reached that code path, we'd have
tried to rebuild all markdown engines every time.
And it also wasn't clearly helpful -- because we fetch all linkifiers
for a realm on every request anyway, we don't really save database
queries by doing a bulk fetch on startup, and doing so would likely
result in a material regression to Zulip's overall startup time that
we were creating markdown engines for large numbers of realms in bulk
during process startup.
The comments explain in some detail, but basically we were displaying
the types for booleans incorrectly, and the types for strings in a
somewhat confusing fashion. Fix this with comments explaining the logic.
Using JSON dumping also results in our showing strings inside
quotation marks in our examples, which seems net helpful.
Thanks to ArunSankarKs for finding where we needed to change the
codebase.
Fixes#18021.
This reverts commit 9c6d8d9d81 (#16916).
This feature has known bugs, and also wants some design changes to
make it customizable like linkifiers, so we’re retargeting this to
post-4.x.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Backend logic for handling user mention was cluttered
because it was handled at two stages first in
get_possible_mentions_info while fetching mention data
based on the messsage and then later in UserMentionPattern
which handles processing of text for mention.
Ideally UserMentionPattern should depend on
get_possible_mentions_info only for data but there was a
shared logic between these two that made it hard to debug
any possible bugs.
Updates in this commit make both of these functions
coherent in terms of logic and also add appropiate
comments to improve readability of these functions.
There was also a hidden bug that if a user A is
mentioned in with @**name|id** then @**invalid|id**
again mentioned A because of the way we handled mentions
earlier. It is solved as a result of this refactor and
appropiate test has been added for this.
This has been tested manually as well as by adding new
test to address missing case.
Extend our markdown system to support mentioning of users
by id also. Following these changes, it would be possible
to mention users with @**|user_id** and silently mention
using @_**|user_id**.
Main intention for extending the mention syntax is to make
it convenient for bots to mention a users using their ids. It
is to be noted that previous syntax are also supported.
Documentation tweaked by tabbott for better readability.
The changes were tested manually in development server, and also
by adding some new backend and frontend tests.
Fixes: #17487.
We add support to shorten links and test their shortening in
well-organized, clean manner that makes it trivial to extend the
GitHub approach for GitLab and perhaps other services.
We only shorten basic types of GitHub links (issue, PR, commit) that
fit a set of simple common patterns; the default behaviour of Autolink
is kept for everything else.
Logic added in frontend and backend Markdown Processor is identical.
This makes easy to extend the logic for other services like GitLab.
Fixes#11895.
Modifies `StreamPattern` and `StreamTopicPattern` to inherit
from InlineProcessor instead of Pattern. This change is done
because Pattern stopped checking for matching patterns as soon
as it found a match which was not a valid stream. Due to this
all the subsequent mention failed, even if they were valid.
This bug was only present in backend renderring due to
markdown.inlinepatterns.Pattern.
Due to above changes verbose_compile is no longer used for
precompiling STREAM_LINK_REGEX, STREAM_TOPIC_LINK_REGEX as
adds ^(.*?) and (.*?)$ which cause extra overhead of matching
pattern which is not required. With new InlineProcessor these
extra patterns at beggining and end are not required.
So, StreamPattern and StreamTopicPattern now define their own
__init__ method for precompiling the regex.
Fixes#17535.
These changes were tested locally in dev server and by adding
some new markdown tests to test these.
Modifies `UserGroupMentionPattern` to inherit from InlineProcessor
instead of Pattern. This change is done because Pattern
stopped checking for matching patterns as soon as it found
a match which was not a valid user group. Due to this all
the subsequent user group mention failed, even if they were
valid. This bug was only present in backend renderring due to
markdown.inlinepatterns.Pattern.
This was reported as issue #17535.
These changes were tested locally in dev server and by adding
some new markdown tests to test these.
Modifies `UserMentionPattern` to inherit from InlineProcessor
instead of Pattern. This change is done because Pattern
stopped checking for matching patterns as soon as it found
a match which was not a valid user. Due to this all the
subsequent user mention failed. This bug was only present in
backend renderring due to markdown.inlinepatterns.Pattern.
This was reported as issue #17535.
These changes were tested locally in dev server and by adding
some new markdown tests to test these.
Currently, the ID and Type fields didn't have a description,
and weren't being displayed. Added a schema component to add
descriptions, and display on the api page. Fixes part of #15967.
Added assertion to check that if a deprecated flag is in a field's
schema, then it should have deprecated mentioned in description
as well, and moved these checks to a separate function.
Fixes part of #15967.
The current logic doesn't display data types when the additionalProperties
variables are not object, but are array of strings, etc. Changed the if
condition to allow rendering in such cases.
Previously, the data type of responses wasn't displayed in the API
Documentation, even though that OpenAPI data is carefully validated
against the implementation. Here we add a recursive function to
render the data types visibly in API Documentation.
Fixes part of #15967.
Commit 434094e599 (#11321) changed this
from an Extension to a subclass of Markdown, so it no longer has any
reason to use a config dict structured like that of an Extension.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
The changes are as follows:
• Fix one day offset in all western zones.
• Correct CST from -64800 to -21600 and CDT from -68400 to -18000.
• Disambiguate PST in favor of -28000 over +28000.
• Add GMT, UTC, WET, previously excluded for being at offset 0.
• Add ACDT, AEDT, AKST, MET, MSK, NST, NZDT, PKT, which the previous
code did not find.
• Remove numbered abbreviations -12, …, +14, which are unnecessary.
• Remove MSD and PKST, which are no longer used.
Hardcode the dict and verify it with a test, so that future
discrepancies won’t go silently unnoticed.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Previously, the data type of parameters wasn't displayed in the API
Documentation, even though that OpenAPI data is carefully validated
against the implementation. Here we add a recursive function to
render the data types visibly in the API documentation.
This only covers the request parameters; we'll want to do something
similar for response parameters in a follow-up PR.
Fixes part of #15967.
Alya Abbott
Alex Vandiver
Pradyumna Sinha
Kevin Scott
Eeshan Garg
Mateusz Mandera
Tim Abbott
rht
Anders Kaseorg
Priyansh Garg
Ganesh Pawar
akshatdalton
sahil839
PIG208
Suyash Vardhan Mathur
Wesley Aptekar-Cassels
Abhijeet Prasad Bodas
Sumanth V Rao
m-e-l-u-h-a-n
Aman Agrawal