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aiongg
0c748e34a8
* fix(render): bound xref streams, JBIG2 referred-to counts, saved graphics states and /W2 runs Input bounds and crash fixes in the vendored hayro crates, ported from the snapshot craft-libs carries (storytold/craft-libs#176, #239, #241): - hayro-syntax: an xref stream subsection must be backed by its decoded data. All-zero /W widths and a count longer than the data are refused before any entry is inserted; a tiny stream with a large /Size or /Index count inserted that many entries. - hayro-syntax: a subsection running past object number u32::MAX is refused; start + i overflowed. - hayro-syntax: the xref stream type field is read big-endian at its full /W[0] width, and /W[0] over 8 bytes is refused like /W[1]. - hayro-jbig2: the long-form referred-to segment count is capped at u16::MAX before its retention bytes are read; the 29-bit count went straight to Vec::with_capacity (about 2 GiB) and aborted the process. - hayro-interpret: at most 4096 saved graphics states holding at most 64 MiB together. A q past either limit is counted but not copied, and its Q still removes the clips added since. - hayro-interpret: a /W2 run whose first CID is past MAX_CID stops there, as /W does; a first CID of 4294967295 discarded the whole /W2 table. Each patch is marked in the source, has a regression test in its crate, and is listed in vendor/README.md. * fix(render): a binary usecmap counts against the CMap nesting limit; /W2 checks the CID first - hayro-cmap: a binary CMap's usecmap passed its own depth to the nested parse, so a self-referencing binary CMap recursed until the stack overflowed. It now counts like a text usecmap (ledger hayro-cmap 2). - hayro-interpret: the /W2 first-CID check runs before the run's metrics are read, so an incomplete run past MAX_CID no longer discards the rest of the table (ledger 52). * fix(render): refuse xref-stream object numbers past i32::MAX ObjectIdentifier stores an i32; a number between i32::MAX and u32::MAX was cast to a negative object number (ledger hayro-syntax 26).
hayro-jbig2
A memory-safe, pure-Rust JBIG2 decoder.
hayro-jbig2 decodes JBIG2 images as specified in ITU-T T.88 (also known as
ISO/IEC 14492). JBIG2 is a bi-level image compression standard commonly used
in PDF documents for compressing scanned text documents.
Status
This crate is currently under development.
Safety
By default, the crate has the simd feature enabled, which uses the
fearless_simd crate to accelerate decoding of JBIG2 images with halftoning.
If you want to eliminate any usage of unsafe in this crate as well as its dependencies, you can simply disable this
feature and still get very good performance in the vast majority of cases. Unsafe code is forbidden
via a crate-level attribute.
License
Licensed under either of
- Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
at your option.