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Felipe Moura ce645060fa crypto: add CRYPTO_AES_CTR_SSH variant (128-bit big-endian counter)
The existing CRYPTO_AES_CTR is the RFC 3686 profile: the last 4 bytes of
the key are a nonce, the IV is 8 bytes and only the low 32 bits of the
counter block are incremented. SSH aes128/192/256-ctr (RFC 4344) instead
uses the key as-is (no embedded nonce) and treats the whole 16-byte IV as
the initial counter block, incremented as a 128-bit big-endian integer,
with the first keystream block being E(IV).

Add CRYPTO_AES_CTR_SSH as a new enc_xform mirroring the CRYPTO_CHACHA20_DJB
addition. It reuses struct aes_ctr_ctx and the AES block; only setkey (full
key, no nonce), reinit (full 16-byte counter) and crypt (encrypt-then-
increment over all 16 bytes) differ from the RFC 3686 variant.

Keystream validated against `openssl enc -aes-128-ctr`, including a counter
that carries across byte boundaries and a non-block-aligned tail.

Signed-off-by: Felipe Moura <moura.fmo@gmail.com>
2026-07-16 15:42:10 +08:00
.github ci/testing: MemBrowse Doc only change detection fix 2026-07-14 11:03:49 -03:00
arch arch/risc-v: preserve ra across ecall for fp-chain backtrace 2026-07-16 15:24:12 +08:00
audio drivers/efuse/efuse: Drivers Registered With World Write Permissions(Part 1) 2026-07-13 12:08:01 +02:00
binfmt elf:use elf symbol to parse attribute 2026-07-15 12:24:44 -03:00
boards boards/stm32f3: nucleo-f302r8:ihm07m1_b16: enable LTO to fit flash 2026-07-16 08:12:38 +02:00
cmake elf:use elf symbol to parse attribute 2026-07-15 12:24:44 -03:00
crypto crypto: add CRYPTO_AES_CTR_SSH variant (128-bit big-endian counter) 2026-07-16 15:42:10 +08:00
Documentation docs/audio_rttl: Document the RTTL audio player 2026-07-15 16:15:42 -03:00
drivers arch/mips: Add basic support for MIPS Creator CI20 board 2026-07-15 08:02:55 -03:00
dummy
fs drivers/: Multiple Drivers Are Registered With World Writable - Part 2 2026-07-15 15:27:28 +08:00
graphics drivers/: Multiple Drivers Are Registered With World Writable - Part 2 2026-07-15 15:27:28 +08:00
include crypto: add CRYPTO_AES_CTR_SSH variant (128-bit big-endian counter) 2026-07-16 15:42:10 +08:00
libs spawn: allow zero stacksize/priority to use binary loader defaults 2026-07-15 12:24:44 -03:00
mm arch/mips: Add basic support for MIPS Creator CI20 board 2026-07-15 08:02:55 -03:00
net fix(net/igmp): restore General Query handling broken by pointer compare 2026-07-15 08:46:23 +02:00
openamp openamp: fix CMake dcache option 2026-05-10 15:03:24 +02:00
pass1 Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
sched spawn: allow zero stacksize/priority to use binary loader defaults 2026-07-15 12:24:44 -03:00
syscall syscall: fcntl param3 type to uintptr_t 2026-04-27 12:01:55 -03:00
tools ci/platforms/darwin.sh: fix genromfs installation 2026-07-12 22:21:24 +02:00
video video: ensure video library is non-empty 2026-05-08 19:51:39 +08:00
wireless drivers/: Multiple Drivers Are Registered With World Writable - Part 2 2026-07-15 15:27:28 +08:00
.asf.yaml github: master branch protection tune. 2025-05-07 18:37:13 -05:00
.codespell-ignore-lines !boards: Remove NSH_ARCHINIT and board_app_initialize 2026-05-02 18:36:46 +08:00
.codespellrc arch/sim: replace macOS C++ constructor runtime hack with post-link patch 2026-05-19 07:08:55 -03:00
.editorconfig .editorconfig: fix character encoding property specification 2025-11-28 19:12:13 +08:00
.gitignore git: Specify multiple build directories in .gitignore. 2026-05-20 03:06:58 +08:00
.gitmessage docs/contributing: Add a commit message template 2025-06-03 17:33:24 +08:00
.pre-commit-config.yaml pre-commit: enable codespell checks 2025-05-05 12:34:39 +08:00
.yamllint
AUTHORS AUTHORS: add Eren Terzioglu 2026-05-20 15:17:00 +08:00
CMakeLists.txt cmake/nuttx_toolchain.cmake: track preprocessed include deps 2026-06-04 17:22:43 +08:00
CONTRIBUTING.md contributing: Add requirement for 'Assisted-by' commit field 2026-07-12 09:42:28 +08:00
INVIOLABLES.md
Kconfig sched/misc/assert: Add CONFIG_SCHED_DUMP_TASKS and CONFIG_SCHED_DUMP_STACK 2026-06-09 08:04:54 -04:00
LICENSE libs/libdsp: Add Matrix operations 2026-07-11 14:55:59 -03:00
Makefile !boards: enforce secure ROMFS passwd and TEA key setup 2026-07-09 22:41:11 +08:00
NOTICE
README.md ci/testing: Add MemBrowse Integration 2026-06-18 12:07:41 -03:00
ReleaseNotes Documentation: move ReleaseNotes 2023-09-26 20:41:00 +08:00

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Apache NuttX is a real-time operating system (RTOS) with an emphasis on standards compliance and small footprint. Scalable from 8-bit to 64-bit microcontroller environments, the primary governing standards in NuttX are POSIX and ANSI standards. Additional standard APIs from Unix and other common RTOSs (such as VxWorks) are adopted for functionality not available under these standards, or for functionality that is not appropriate for deeply-embedded environments (such as fork()).

For brevity, many parts of the documentation will refer to Apache NuttX as simply NuttX.

Getting Started

First time on NuttX? Read the Getting Started guide! If you don't have a board available, NuttX has its own simulator that you can run on terminal.

Documentation

You can find the current NuttX documentation on the Documentation Page.

Alternatively, you can build the documentation yourself by following the Documentation Build Instructions.

The old NuttX documentation is still available in the Apache wiki.

Supported Boards

NuttX supports a wide variety of platforms. See the full list on the Supported Platforms page.

Contributing

If you wish to contribute to the NuttX project, read the Contributing guidelines for information on Git usage, coding standard, workflow and the NuttX principles.

License

The code in this repository is under either the Apache 2 license, or a license compatible with the Apache 2 license. See the License Page for more information.