When an empty string was passed to replaceStreamData, the code was
passing a null pointer to memcpy. Since a 0 size was also passed, this
was harmless, but it triggers sanitizer errors. The code properly
handles a null pointer as the buffer in other places.
Where not possible, use "auto" to get the iterator type.
Editorial note: I have avoid this change for a long time because of
not wanting to make gratuitous changes to version history, which can
obscure when certain changes were made, but with having recently
touched every single file to apply automatic code formatting and with
making several broad changes to the API, I decided it was time to take
the plunge and get rid of the older (pre-C++11) verbose iterator
syntax. The new code is just easier to read and understand, and in
many cases, it will be more effecient as fewer temporary copies are
being made.
m-holger, if you're reading, you can see that I've finally come
around. :-)
Add comments to force line breaks, parenthesize function arguments
that are contatenated strings, etc. -- these kinds of changes improve
clang-format's results and also cause emacs cc-mode to match
clang-format. After this type of change, most of the time, when
clang-format and emacs disagree, clang-format is better.
Remove test for type == /XObject in QPDFObjectHandle::isFormXObject
as type value is optional (as per spec 8.10.2).
Replace code to test for /Form in QPDFJob::shouldRemoveUnreferencedResources
with a call to isFormXObject.
This comment expands all tabs using an 8-character tab-width. You
should ignore this commit when using git blame or use git blame -w.
In the early days, I used to use tabs where possible for indentation,
since emacs did this automatically. In recent years, I have switched
to only using spaces, which means qpdf source code has been a mixture
of spaces and tabs. I have avoided cleaning this up because of not
wanting gratuitous whitespaces change to cloud the output of git
blame, but I changed my mind after discussing with users who view qpdf
source code in editors/IDEs that have other tab widths by default and
in light of the fact that I am planning to start applying automatic
code formatting soon.
Use get() and use_count() instead. Add #define
NO_POINTERHOLDER_DEPRECATION to remove deprecation markers for these
only.
This commit also removes all deprecated PointerHolder API calls from
qpdf's code except in PointerHolder's test suite, which must continue
to test the deprecated APIs.
When adding a QPDFObjectHandle to an array or dictionary, if possible,
check if the new object belongs to the same QPDF. This makes it much
easier to find incorrect code than waiting for the situation to be
detected when the file is written.
This results in a performance penalty of 1% to 2% when replaceObject
and swapObjects are never called and a somewhat larger penalty if they
are called, but it's worth it to avoid very confusing behavior as
discussed in depth in qpdf#507.
Also fix a bug in checking consistency of length for stream data
providers. Length should not be checked or recorded if the provider
says it failed to generate the data.
Avoid calling finish() multiple times on the pipeline passed to
pipeContentStreams. This commit also fixes a bug in which qpdf was not
exiting with the proper exit status if warnings found while splitting
pages; this was exposed by a test case that changed.
Make some more methods in QPDFPageObjectHelper work with form
XObjects, provide forEach methods to walk through nested form
XObjects, possibly recursively. This should make it easier to work
with form XObjects from user code.
Various PDF digital signing tools do not encrypt /Contents value in
signature dictionary. Adobe Acrobat Reader DC can handle a PDF with
the /Contents value not encrypted.
Write Contents in signature dictionary without encryption
Tests ensure that string /Contents are not handled specially when not
found in sig dicts.
* Several assertions in linearization were not always true; change
them to run time errors
* Handle a few cases of uninitialized objects
* Handle pages with no contents when doing form operations
* Handle invalid page tree nodes when traversing pages
This makes all integer type conversions that have potential data loss
explicit with calls that do range checks and raise an exception. After
this commit, qpdf builds with no warnings when -Wsign-conversion
-Wconversion is used with gcc or clang or when -W3 -Wd4800 is used
with MSVC. This significantly reduces the likelihood of potential
crashes from bogus integer values.
There are some parts of the code that take int when they should take
size_t or an offset. Such places would make qpdf not support files
with more than 2^31 of something that usually wouldn't be so large. In
the event that such a file shows up and is valid, at least qpdf would
raise an error in the right spot so the issue could be legitimately
addressed rather than failing in some weird way because of a silent
overflow condition.
Add a version of expectInlineImage that takes an input source and
searches for EI. This is in preparation for improving the way EI is
found. This commit just refactors the code without changing the
functionality and adds tests to make sure the old and new code behave
identically.
Instead of directly putting the contents of the annotation appearance
streams into the page's content stream, add commands to render the
form xobjects directly. This is a more robust way to do it than the
original solution as it works properly with patterns and avoids
problems with resource name clashes between the pages and the form
xobjects.
If parsing content streams is treated as a warning, there is no way
for a caller to know if a parsing operation has failed. This is very
dangerous and will likely result in data loss when token filters are
parser callbacks are in use.
It's not really a shallow copy. It just doesn't cross indirect object
boundaries. The old implementation had a bug that would cause multiple
shallow copies of the same object to share memory, which was not the
intention.
Remove calls to assertPageObject(). All cases in the library that
called assertPageObject() work fine if you don't call
assertPageObject() because nothing assumes anything that was being
checked by that call. Removing the calls enables more files to be
successfully processed.
Implement a TokenFilter class and refactor Pl_QPDFTokenizer to use a
TokenFilter class called ContentNormalizer. Pl_QPDFTokenizer is now a
general filter that passes data through a TokenFilter.
Remove a redundant method that was equal to another one with
additional arguments. This breaks binary compatibility, but there are
other ABI breaking changes in the upcoming release, so now is the time
to do it.
This commit adds several API methods that enable control over which
types of filters QPDF will attempt to decode. It also adds support for
/RunLengthDecode and /DCTDecode filters for both encoding and
decoding.
When requested, QPDFWriter will do more aggress prechecking of streams
to make sure it can actually succeed in decoding them before
attempting to do so. This will allow preservation of raw data even
when the raw data is corrupted relative to the specified filters.
QPDFObjectHandle::parseInternal now issues warnings instead of
throwing exceptions for all error conditions that it finds (except
internal logic errors) and has stronger recovery for things like
invalid tokens and malformed dictionaries. This should improve qpdf's
ability to recover from a wide range of broken files that currently
cause it to fail.
This is CVE-2017-9208.
The QPDF library uses object ID 0 internally as a sentinel to
represent a direct object, but prior to this fix, was not blocking
handling of 0 0 obj or 0 0 R as a special case. Creating an object in
the file with 0 0 obj could cause various infinite loops. The PDF spec
doesn't allow for object 0. Having qpdf handle object 0 might be a
better fix, but changing all the places in the code that assumes objid
== 0 means direct would be risky.
This is CVE-2017-9210.
The description string for an error message included unparsing an
object, which is too complex of a thing to try to do while throwing an
exception. There was only one example of this in the entire codebase,
so it is not a pervasive problem. Fixing this eliminated one class of
infinite loop errors.
When checking two objects preceding R while parsing, ensure that the
objects are direct. This avoids stuff like 1 0 obj containing 1 0 R 0 R
from causing an infinite loop in object resolution.