[lealem47]

Description

Account for the tightening of args in #12059.

This PR fixes general openssl compat for 0 salt encrypt's. Observed through wolfCLU failures.

Testing

./configure --enable-wolfclu && make & make install in wolfSSL

./configure && make check in wolfclu

Checklist

• added tests
• updated/added doxygen
• updated appropriate READMEs
• Updated manual and documentation

[Copilot]

🟢 Approval recommended

No active review issues are identified for the change restoring unsalted EVP_BytesToKey compatibility.

No open issues 🎉

What changed in this PR

Restores unsalted EVP_BytesToKey compatibility after #12059 tightened wc_PBKDF1_ex argument validation, addressing the reported wolfCLU failures.

Changes:

• Passes a zero salt length when the salt pointer is NULL, preserving the eight-byte length for present salts.
• Adds an AES-128-CBC/SHA-256 regression case that checks the derived key and IV without salt.

File	Description
wolfcrypt/​src/​evp.c	Makes the KDF salt length match salt presence.
tests/​api/​test_evp_cipher.c	Adds expected key and IV assertions for unsalted derivation.

_{Review effort: Balanced}

[github-actions]

MemBrowse Memory Report · Explore what changed →

No memory changes detected for:

• gcc-arm-cortex-m0plus
• gcc-arm-cortex-m3
• gcc-arm-cortex-m4
• gcc-arm-cortex-m4-baremetal
• gcc-arm-cortex-m4-crypto-only
• gcc-arm-cortex-m4-dtls13
• gcc-arm-cortex-m4-min-ecc
• gcc-arm-cortex-m4-openssl-compat
• gcc-arm-cortex-m4-pkcs7
• gcc-arm-cortex-m4-pq
• gcc-arm-cortex-m4-rsa-only
• gcc-arm-cortex-m4-sp-math
• gcc-arm-cortex-m4-tls12
• gcc-arm-cortex-m4-tls13
• gcc-arm-cortex-m7
• gcc-arm-cortex-m7-pq
• gcc-arm-cortex-m7-tls13
• stm32-sim-stm32h753
• zephyr-frdm_rw612

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