43422deed3
The lantiq AES hardware does not support the xts algorithm. Apart from the cipher text stealing (XTS), the AES XTS implementation is just an XOR with the IV, followed by AES ECB, followed by another XOR with the IV and as such can be also implemented by using the lantiq hardware's CBC AES implemention plus one additional XOR with the IV in the driver. The output IV by CBC AES is also not usable and the gfmul operation not supported by lantiq hardware. Both need to be done in the driver too in addition to the IV treatment which is the initial encryption by the other half of the input key and to set the IV to the IV registers for every block. In the generic kernel implementation, the block size for XTS is set to 16 bytes, although the algorithm is designed to process any size of input larger than 16 bytes. But since there is no way to indicate a minimum input length, the block size is used. This leads to certain issues when the skcipher walk functions are used, e.g. processing less than block size bytes is not supported by calling skcipher_walk_done. The walksize is 2 AES blocks because otherwise for splitted input or output data, less than blocksize is to be returned in some cases, which cannot be processed. Another issue was that depending on possible split of input/output data, just 16 bytes are returned while less than 16 bytes were remaining, while cipher text stealing requires 17 bytes or more for processing. For example, if the input is 60 bytes and the walk is 48, then processing 48 bytes leads to a return code of -EINVAL for skcipher_walk_done. Therefor the processed counter is used to figure out, when the actual cipher text stealing for the remaining bytes less than blocksize needs to be applied. Measured with cryptsetup benchmark, this XTS AES implementation is about 19% faster than the kernels XTS implementation that uses the hardware ECB AES (ca. 18.6 MiB/s vs. 15.8 MiB/s decryption 256b key). The implementation was tested with the kernels crypto testmgr against the kernels generic XTS AES implementation including extended tests. Signed-off-by: Daniel Kestrel <kestrel1974@t-online.de> |
||
|---|---|---|
| .github | ||
| config | ||
| include | ||
| LICENSES | ||
| package | ||
| scripts | ||
| target | ||
| toolchain | ||
| tools | ||
| .gitattributes | ||
| .gitignore | ||
| BSDmakefile | ||
| Config.in | ||
| COPYING | ||
| feeds.conf.default | ||
| Makefile | ||
| README.md | ||
| rules.mk | ||
OpenWrt Project is a Linux operating system targeting embedded devices. Instead of trying to create a single, static firmware, OpenWrt provides a fully writable filesystem with package management. This frees you from the application selection and configuration provided by the vendor and allows you to customize the device through the use of packages to suit any application. For developers, OpenWrt is the framework to build an application without having to build a complete firmware around it; for users this means the ability for full customization, to use the device in ways never envisioned.
Sunshine!
Development
To build your own firmware you need a GNU/Linux, BSD or MacOSX system (case sensitive filesystem required). Cygwin is unsupported because of the lack of a case sensitive file system.
Requirements
You need the following tools to compile OpenWrt, the package names vary between distributions. A complete list with distribution specific packages is found in the Build System Setup documentation.
binutils bzip2 diff find flex gawk gcc-6+ getopt grep install libc-dev libz-dev
make4.1+ perl python3.6+ rsync subversion unzip which
Quickstart
-
Run
./scripts/feeds update -ato obtain all the latest package definitions defined in feeds.conf / feeds.conf.default -
Run
./scripts/feeds install -ato install symlinks for all obtained packages into package/feeds/ -
Run
make menuconfigto select your preferred configuration for the toolchain, target system & firmware packages. -
Run
maketo build your firmware. This will download all sources, build the cross-compile toolchain and then cross-compile the GNU/Linux kernel & all chosen applications for your target system.
Related Repositories
The main repository uses multiple sub-repositories to manage packages of
different categories. All packages are installed via the OpenWrt package
manager called opkg. If you're looking to develop the web interface or port
packages to OpenWrt, please find the fitting repository below.
-
LuCI Web Interface: Modern and modular interface to control the device via a web browser.
-
OpenWrt Packages: Community repository of ported packages.
-
OpenWrt Routing: Packages specifically focused on (mesh) routing.
-
OpenWrt Video: Packages specifically focused on display servers and clients (Xorg and Wayland).
Support Information
For a list of supported devices see the OpenWrt Hardware Database
Documentation
Support Community
- Forum: For usage, projects, discussions and hardware advise.
- Support Chat: Channel
#openwrton oftc.net.
Developer Community
- Bug Reports: Report bugs in OpenWrt
- Dev Mailing List: Send patches
- Dev Chat: Channel
#openwrt-develon oftc.net.
License
OpenWrt is licensed under GPL-2.0