* fix smallstackcache memory leaks in sha256 and sha512 contexts -- don't init or copy over a context that's been inited but not freed, and make sure to explicitly free any context that's been inited or copied over.
* fix uninited-var warnings in slhdsakey_wots_sign(), slhdsakey_xmss_sign(), and slhdsakey_fors_sign() (the uninited-var scenario depends on corrupt arg(s) resulting in zero iterations).
Add SRAM PUF (Physically Unclonable Function) support to wolfCrypt. Derives device-unique cryptographic keys from the power-on state of SRAM memory using a BCH(127,64,t=10) fuzzy extractor with HKDF key derivation.
- **wolfCrypt PUF API** (`wolfcrypt/src/puf.c`, `wolfssl/wolfcrypt/puf.h`)
- `wc_PufInit`, `wc_PufReadSram`, `wc_PufEnroll`, `wc_PufReconstruct`
- `wc_PufDeriveKey` (HKDF-SHA256), `wc_PufGetIdentity` (SHA-256 device fingerprint)
- `wc_PufZeroize` (secure context cleanup)
- `wc_PufSetTestData` (synthetic SRAM for testing without hardware)
- **BCH(127,64,t=10) error-correcting codec** - corrects up to 10 bit flips per 127-bit codeword across 16 codewords
- **`WC_PUF_SHA3` build option** - select SHA3-256 instead of SHA-256 for identity hash and HKDF (default: SHA-256)
- **Precomputed GF(2^7) tables** - `const` arrays in `.rodata` (no runtime init, thread-safe, flash-resident on embedded)
- `./configure --enable-puf` (auto-enables HKDF dependency)
- CMake: `WOLFSSL_PUF=yes`
- `WOLFSSL_USER_SETTINGS`: define `WOLFSSL_PUF` and `WOLFSSL_PUF_SRAM`
- See wolfssl-examples/puf for example implementation on STM32 NUCLEO-H563ZI (Cortex-M33, STM32H563ZI)
- Supports test mode (synthetic SRAM)
- Builds to ~13KB `.elf`
- Tested on NUCLEO-H563ZI: enrollment, noisy reconstruction, key derivation all pass
- `.github/workflows/puf.yml`: host build + test workflow for PUF feature
- Doxygen API docs for all 8 public functions
- PUF group added to `doxygen_groups.h`
Follow-up to #7731 ("Changes needed for default TLS support in zephyr
kernel"). Zephyr 4.3's TLS socket integration uses three additional
wolfSSL features that were not needed by the 3.7 integration, plus an
extension to the native_sim time-source gates introduced in #7731.
native_sim timer gates (src/internal.c, wolfcrypt/src/wc_port.c):
Extend the !CONFIG_BOARD_NATIVE_POSIX gate in LowResTimer() and the
CONFIG_BOARD_NATIVE_POSIX RTC path in z_time() to also cover
CONFIG_BOARD_NATIVE_SIM. Zephyr 4.3 renamed the simulator board from
native_posix to native_sim; without this, k_cpu_idle() on native_sim
advances simulated time during DTLS retransmit loops and the RTC path
falls through to uptime-since-boot. Behavior on native_posix is
unchanged.
New Kconfig options (zephyr/Kconfig, zephyr/user_settings.h):
CONFIG_WOLFSSL_SESSION_EXPORT -> HAVE_EXT_CACHE
Required by consumers that serialize TLS session state across
connections via wolfSSL_i2d_SSL_SESSION / wolfSSL_d2i_SSL_SESSION.
CONFIG_WOLFSSL_KEEP_PEER_CERT -> KEEP_PEER_CERT
Retain the peer certificate after handshake so the application
layer can inspect it via wolfSSL_get_peer_certificate.
CONFIG_WOLFSSL_ALWAYS_VERIFY_CB -> WOLFSSL_ALWAYS_VERIFY_CB
Invoke an application-set verify callback on successful chain
validation in addition to validation failures.
All three are default-off; customers opt in the same way they do for
the existing CONFIG_WOLFSSL_DTLS / ALPN / PSK feature options.
.wolfssl_known_macro_extras: register HAVE_EXT_CACHE.
Daniel Pouzzner
David Garske
JacobBarthelmeh
kaleb-himes
Eric Blankenhorn
Juliusz Sosinowicz
Sean Parkinson
Tobias Frauenschläger
Kareem
Paul Adelsbach
Colton Willey
Jeremiah Mackey