linuxkm: handle RHEL9 disabled akcipher sign/decrypt ops #9597
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sameehj
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douzzer
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Dec 31, 2025
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With the fix to the #include clause, this works!
[ 0.000000] Linux version 5.14.0-xxx-rhel9v6 (douzzer@ganglion) (gcc (Gentoo 14.3.1_p20250718 p2) 14.3.1 20250718, GNU ld (Gentoo 2.44 p4) 2.44.0) #1 SMP PREEMPT_DYNAMIC Thu Aug 7 14:25:47 CDT 2025
[...]
[ 38.370118] ecdsa-nist-p521-fips-140-3-wolfcrypt self-test OK -- registered for ecdsa-nist-p521 with priority 100000.
[ 38.370163] alg: ecdh-nist-p256 (ecdh-nist-p256-fips-140-3-wolfcrypt) is disabled due to FIPS
[ 38.370171] info: skipping unsupported kpp algorithm ecdh-nist-p256-fips-140-3-wolfcrypt: -2
[ 38.370172] wolfCrypt: skipping FIPS-incompatible alg ecdh-nist-p256-fips-140-3-wolfcrypt.
[ 38.370235] alg: ecdh-nist-p384 (ecdh-nist-p384-fips-140-3-wolfcrypt) is disabled due to FIPS
[ 38.370248] info: skipping unsupported kpp algorithm ecdh-nist-p384-fips-140-3-wolfcrypt: -2
[ 38.370249] wolfCrypt: skipping FIPS-incompatible alg ecdh-nist-p384-fips-140-3-wolfcrypt.
[ 38.370333] alg: self-tests for pkcs1pad(rsa-fips-140-3-wolfcrypt,sha224) (pkcs1pad(rsa,sha224)) passed
[ 38.466589] info: skipping crypto_akcipher_sign (disabled by RHEL policy)
[ 38.466595] pkcs1pad(rsa-fips-140-3-wolfcrypt,sha224) self-test OK -- registered for pkcs1pad(rsa,sha224) with priority 100000.
[ 38.466830] alg: self-tests for pkcs1pad(rsa-fips-140-3-wolfcrypt,sha256) (pkcs1pad(rsa,sha256)) passed
[ 38.529209] info: skipping crypto_akcipher_sign (disabled by RHEL policy)
[ 38.529217] pkcs1pad(rsa-fips-140-3-wolfcrypt,sha256) self-test OK -- registered for pkcs1pad(rsa,sha256) with priority 100000.
[ 38.529363] alg: self-tests for pkcs1pad(rsa-fips-140-3-wolfcrypt,sha384) (pkcs1pad(rsa,sha384)) passed
[ 38.794341] info: skipping crypto_akcipher_sign (disabled by RHEL policy)
[ 38.794349] pkcs1pad(rsa-fips-140-3-wolfcrypt,sha384) self-test OK -- registered for pkcs1pad(rsa,sha384) with priority 100000.
[ 38.794491] alg: self-tests for pkcs1pad(rsa-fips-140-3-wolfcrypt,sha512) (pkcs1pad(rsa,sha512)) passed
[ 38.820485] info: skipping crypto_akcipher_sign (disabled by RHEL policy)
[ 38.820490] pkcs1pad(rsa-fips-140-3-wolfcrypt,sha512) self-test OK -- registered for pkcs1pad(rsa,sha512) with priority 100000.
[ 38.820599] alg: No test for pkcs1pad(rsa,sha3-256) (pkcs1pad(rsa-fips-140-3-wolfcrypt,sha3-256))
[ 38.887265] info: skipping crypto_akcipher_sign (disabled by RHEL policy)
[ 38.887272] pkcs1pad(rsa-fips-140-3-wolfcrypt,sha3-256) self-test OK -- registered for pkcs1pad(rsa,sha3-256) with priority 100000.
[ 38.887397] alg: No test for pkcs1pad(rsa,sha3-384) (pkcs1pad(rsa-fips-140-3-wolfcrypt,sha3-384))
[ 38.920057] info: skipping crypto_akcipher_sign (disabled by RHEL policy)
[ 38.920064] pkcs1pad(rsa-fips-140-3-wolfcrypt,sha3-384) self-test OK -- registered for pkcs1pad(rsa,sha3-384) with priority 100000.
[ 38.920215] alg: No test for pkcs1pad(rsa,sha3-512) (pkcs1pad(rsa-fips-140-3-wolfcrypt,sha3-512))
[ 39.002644] info: skipping crypto_akcipher_sign (disabled by RHEL policy)
[ 39.002650] pkcs1pad(rsa-fips-140-3-wolfcrypt,sha3-512) self-test OK -- registered for pkcs1pad(rsa,sha3-512) with priority 100000.
[ 39.002803] alg: self-tests for rsa-fips-140-3-wolfcrypt (rsa) passed
[ 39.077305] info: skipping crypto_akcipher_decrypt (disabled by RHEL policy)
[ 39.077311] rsa-fips-140-3-wolfcrypt self-test OK -- registered for rsa with priority 100000.
[...]
[ 42.364971] wolfCrypt: 43 algorithms registered.
[ 42.364978] wolfCrypt 5.8.4 loaded with valid module signature.
[ 42.364978] See https://www.wolfssl.com/ for more information.
[ 42.364978] wolfCrypt Copyright (C) 2006-present wolfSSL Inc. Licensed under GPL.
RHEL9 kernels (9.6+) disable RSA signing and decryption in the kernel crypto API for security reasons (CVE-2023-6240). The kernel forcibly overwrites akcipher sign/decrypt callbacks to return -ENOSYS, regardless of what the driver provides. Commit 3709c35c in the RHEL kernel: "crypto: akcipher - Disable signing and decryption" This affects our self-tests which call crypto_akcipher_sign() and crypto_akcipher_decrypt(). On RHEL9, these operations return -ENOSYS even though our driver correctly implements them. Add compile-time checks for RHEL_RELEASE_CODE >= 9.6 to detect this scenario and skip the affected self-tests gracefully. The tests pass since the algorithms are registered correctly; the kernel simply refuses to execute sign/decrypt operations as a matter of policy. Note: encrypt and verify operations are unaffected and continue to be tested normally. Signed-off-by: Sameeh Jubran <[email protected]>
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RHEL9 kernels (9.6+) disable RSA signing and decryption in the kernel crypto API for security reasons (CVE-2023-6240). The kernel forcibly overwrites akcipher sign/decrypt callbacks to return -ENOSYS, regardless of what the driver provides.
Commit 3709c35c in the RHEL kernel:
"crypto: akcipher - Disable signing and decryption"
This affects our self-tests which call crypto_akcipher_sign() and crypto_akcipher_decrypt(). On RHEL9, these operations return -ENOSYS even though our driver correctly implements them.
Add compile-time checks for RHEL_RELEASE_CODE >= 9.6 to detect this scenario and skip the affected self-tests gracefully. The tests pass since the algorithms are registered correctly; the kernel simply refuses to execute sign/decrypt operations as a matter of policy.
Note: encrypt and verify operations are unaffected and continue to be tested normally.
https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/commit/3709c35cf173f886689e201914911b464881c947
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