Related issues:
- https://github.com/uBlockOrigin/uBlock-issues/issues/761
- https://github.com/uBlockOrigin/uBlock-issues/issues/528
The previous bidi-trie code could only hold filters which
are plain pattern, i.e. no wildcard characters, and which
had no origin option (`domain=`), right and/or left anchor,
and no `csp=` option.
Example of filters that could be moved into a bidi-trie
data structure:
&ad_box_
/w/d/capu.php?z=$script,third-party
||liveonlinetv247.com/images/muvixx-150x50-watch-now-in-hd-play-btn.gif
Examples of filters that could NOT be moved to a bidi-trie:
-adap.$domain=~l-adap.org
/tsc.php?*&ses=
||ibsrv.net/*forumsponsor$domain=[...]
@@||imgspice.com/jquery.cookie.js|$script
||view.atdmt.com^*/iview/$third-party
||postimg.cc/image/$csp=[...]
Ideally the filters above should be able to be moved to a
bidi-trie since they are basically plain patterns, or at
least partially moved to a bidi-trie when there is only a
single wildcard (i.e. made of two plain patterns).
Also, there were two distinct bidi-tries in which
plain-pattern filters can be moved to: one for patterns
without hostname anchoring and another one for patterns
with hostname-anchoring. This was required because the
hostname-anchored patterns have an extra condition which
is outside the bidi-trie knowledge.
This commit expands the number of filters which can be
stored in the bidi-trie, and also remove the need to
use two distinct bidi-tries.
- Added ability to associate a pattern with an integer
in the bidi-trie [1].
- The bidi-trie match code passes this externally
provided integer when calling an externally
provided method used for testing extra conditions
that may be present for a plain pattern found to
be matching in the bidi-trie.
- Decomposed existing filters into smaller logical units:
- FilterPlainLeftAnchored =>
FilterPatternPlain +
FilterAnchorLeft
- FilterPlainRightAnchored =>
FilterPatternPlain +
FilterAnchorRight
- FilterExactMatch =>
FilterPatternPlain +
FilterAnchorLeft +
FilterAnchorRight
- FilterPlainHnAnchored =>
FilterPatternPlain +
FilterAnchorHn
- FilterWildcard1 =>
FilterPatternPlain + [
FilterPatternLeft or
FilterPatternRight
]
- FilterWildcard1HnAnchored =>
FilterPatternPlain + [
FilterPatternLeft or
FilterPatternRight
] +
FilterAnchorHn
- FilterGenericHnAnchored =>
FilterPatternGeneric +
FilterAnchorHn
- FilterGenericHnAndRightAnchored =>
FilterPatternGeneric +
FilterAnchorRight +
FilterAnchorHn
- FilterOriginMixedSet =>
FilterOriginMissSet +
FilterOriginHitSet
- Instances of FilterOrigin[...], FilterDataHolder
can also be added to a composite filter to
represent `domain=` and `csp=` options.
- Added a new filter class, FilterComposite, for
filters which are a combination of two or more
logical units. A FilterComposite instance is a
match when *all* filters composing it are a
match.
Since filters are now encoded into combination of
smaller units, it becomes possible to extract the
FilterPatternPlain component and store it in the
bidi-trie, and use the integer as a handle for the
remaining extra conditions, if any.
Since a single pattern in the bidi-trie may be a
component for different filters, the associated
integer points to a sequence of extra conditions,
and a match occurs as soon as one of the extra
conditions (which may itself be a sequence of
conditions) is fulfilled.
Decomposing filters which are currently single
instance into sequences of smaller logical filters
means increasing the storage and CPU overhead when
evaluating such filters. The CPU overhead is
compensated by the fact that more filters can now
moved into the bidi-trie, where the first match is
efficiently evaluated. The extra conditions have to
be evaluated if and only if there is a match in the
bidi-trie.
The storage overhead is compensated by the
bidi-trie's intrinsic nature of merging similar
patterns.
Furthermore, the storage overhead is reduced by no
longer using JavaScript array to store collection
of filters (which is what FilterComposite is):
the same technique used in [2] is imported to store
sequences of filters.
A sequence of filters is a sequence of integer pairs
where the first integer is an index to an actual
filter instance stored in a global array of filters
(`filterUnits`), while the second integer is an index
to the next pair in the sequence -- which means all
sequences of filters are encoded in one single array
of integers (`filterSequences` => Uint32Array). As
a result, a sequence of filters can be represented by
one single integer -- an index to the first pair --
regardless of the number of filters in the sequence.
This representation is further leveraged to replace
the use of JavaScript array in FilterBucket [3],
which used a JavaScript array to store collection
of filters. Doing so means there is no more need for
FilterPair [4], which purpose was to be a lightweight
representation when there was only two filters in a
collection.
As a result of the above changes, the map of `token`
(integer) => filter instance (object) used to
associate tokens to filters or collections of filters
is replaced with a more efficient map of `token`
(integer) to filter unit index (integer) to lookup a
filter object from the global `filterUnits` array.
Another consequence of using one single global
array to store all filter instances means we can reuse
existing instances when a logical filter instance is
parameter-less, which is the case for FilterAnchorLeft,
FilterAnchorRight, FilterAnchorHn, the index to these
single instances is reused where needed.
`urlTokenizer` now stores the character codes of the
scanned URL into a bidi-trie buffer, for reuse when
string matching methods are called.
New method: `tokenHistogram()`, used to generate
histograms of occurrences of token extracted from URLs
in built-in benchmark. The top results of the "miss"
histogram are used as "bad tokens", i.e. tokens to
avoid if possible when compiling filter lists.
All plain pattern strings are now stored in the
bidi-trie memory buffer, regardless of whether they
will be used in the trie proper or not.
Three methods have been added to the bidi-trie to test
stored string against the URL which is also stored in
then bidi-trie.
FilterParser is now instanciated on demand and
released when no longer used.
***
[1] 135a45a878/src/js/strie.js (L120)
[2] e94024d350
[3] 135a45a878/src/js/static-net-filtering.js (L1630)
[4] 135a45a878/src/js/static-net-filtering.js (L1566)
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/701
The filter option `empty` is converted to `redirect=empty`
by uBO internally; however unlike when the `redirect=`
option is used expressly, the `empty` option does not
require a resource type.
When `empty` is used, only network requests which are meant
to return a text response will be redirected to an empty
response body by uBO -- so `empty` will not work for
resources such as images, media, or other binary resources.
The ability to redirect xmlhttprequest to binary
resources was lost when redirectable/injectable
resources became immutable in commit
152cea2dfe.
This commit restores the ability to redirect a
xmlhttprequest to a binary resource by making
it possible to derive a data: URI from the
content of binary resources such as images.
Addtionally a redirect to a data: URI can be
forced by prefixing the resource token with `%`.
This is a non-official feature at this point,
i.e. it could be removed at any time.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/310
The purpose of this new option is to add the ability
to create standalone redirect rule without being forced
to create a block filter (a corresponding block filter
is always created when using the `redirect=`).
Additionally:
The syntax `*$redirect=token,...` is now supported, there
is no need to "trick" the filter parser with
`*/*$redirect=token,...` in order to create redirect rules
which are meant to match all paths.
Filters of the form `|http*://` will be normalized into
two corresponding filters `|https://` and `|http://` so as
to reduce the number of filters in the buckets of
untokenizable filters.
Related feedback:
- a54cb2e38f (commitcomment-34387041)
Regression from converting uBO resources into
immutable resources. This affects only Chromium-based
browsers.
This is a quick fix for the dev build, to at least unbreak
the reported case.
I need to research whether the root issue (conflict with HTTPS-E)
is still occurring, and if so the fix is not trivial: I will need
to add code to uBO to fetch and convert binary data into `data:`
URIs.
Make sure the parser is safely compatible with old
resources format -- for those users still using
custom resources (via `userResourcesLocation`).
Prepare code for future fix to
<https://github.com/uBlockOrigin/uBlock-issues/issues/156>:
This commit introduces a new private Map() object,
`uBOSafe`, accessible by all injected scriptlets. This
private safe can be used to store data which can be shared
with different scriptlets. The idea is for scriptlets to
use that safe to graciously deal with the need to install
multiple listeners for the same property.
With hindsight, I revised decisions made earlier during
this development cycle:
Un-redirectable scriptlets have been removed from
/web_accessible_resources and instead put in the new
/assets/resources/scriptlets.js, which contains all
scriptlets used for web page injection purpose.
uBO will no longer fetch a remote version of built-in
resources.
Advanced setting `userResourcesLocation` will still be
honoured by uBO, and if set, will be fetched every
time at least one asset is updated.
This is a first step, the ultimate goal is to remove
the need for resources.txt, or at least to reduce to
only hotfixes or for trivial resources targeting very
specific websites.
Most resources will become immutable, i.e. they will
be part of uBO's code base. Advantages include easier
code maintenance (jshint, syntax highlight), and to
make scriptlets more easy to code review by external
parties (for example extension store reviewers).
TODO:
- More scriptlets need to be imported before next
release.
- Need to make legacy versions of uBO use a legacy
version of resources.txt, as all the now obsolete
scriptlets will have to be removed once uBO's
next release become widespread.
- Possibly need to add code to load binary
resources so that they can be injected as
data: URI. So far it's unclear whether this is
really needed. For example, this would be needed
if a xmlhttprequest is redirected to an image
resource.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/572
Wildcards are now allowed in the hostname part of redirect
filters. There will be an attempt to find the longest
right-hand portion of the hostname with no wildcard. If
no non-empty hostname can be extracted, `*` will be used.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/550
Related Chromium issue (I can't access it):
- https://bugs.chromium.org/p/chromium/issues/detail?id=957866
Findings so far: affects browsers based on Chromium 74.
I could not reproduce the issue with either Chromium 73 or
Google Chrome 75.
This commit is a mitigation: to prevent sites from using
uBO's internal WAR secret for tracking purpose. A secret
can be used for at most one second, after which a new secret
is generated.
The original issue related to the implementation of
secret-gated web accessible resources is:
- https://github.com/gorhill/uBlock/issues/2823
With the new PSL implementation, benchmarks do not show benefit
from caching the domain extracted from a hostname for later
reuse -- the caching seems to even add an overhead instead with
the new publicSuffixList implementation.
The motivation is to address the higher peak memory usage at launch
time with 3rd-gen HNTrie when a selfie was present.
The selfie generation prior to this change was to collect all
filtering data into a single data structure, and then to serialize
that whole structure at once into storage (using JSON.stringify).
However, HNTrie serialization requires that a large UintArray32 be
converted into a plain JS array, which itslef would be indirectly
converted into a JSON string. This was the main reason why peak
memory usage would be higher at launch from selfie, since the JSON
string would need to be wholly unserialized into JS objects, which
themselves would need to be converted into more specialized data
structures (like that Uint32Array one).
The solution to lower peak memory usage at launch is to refactor
selfie generation to allow a more piecemeal approach: each filtering
component is given the ability to serialize itself rather than to be
forced to be embedded in the master selfie. With this approach, the
HNTrie buffer can now serialize to its own storage by converting the
buffer data directly into a string which can be directly sent to
storage. This avoiding expensive intermediate steps such as
converting into a JS array and then to a JSON string.
As part of the refactoring, there was also opportunistic code
upgrade to ES6 and Promise (eventually all of uBO's code will be
proper ES6).
Additionally, the polyfill to bring getBytesInUse() to Firefox has
been revisited to replace the rather expensive previous
implementation with an implementation with virtually no overhead.
* refactoring assets management code
* finalizing refactoring of assets management
* various code review of new assets management code
* fix#2281
* fix#1961
* fix#1293
* fix#1275
* fix update scheduler timing logic
* forward compatibility (to be removed once 1.11+ is widespread)
* more codereview; give admins ability to specify own assets.json
* "assetKey" is more accurate than "path"
* fix group count update when building dom incrementally
* reorganize content (order, added URLs, etc.)
* ability to customize updater through advanced settings
* better spinner icon
