ML-DSA/Dilithium Calls ED

[opencrypto]

There seem to be an issue with the ML-DSA / Dilithium code in WolfCrypt. Specifically, the wc_Dilithium_PublicKeyToDer, calls the SetAsymDerPublic() here:

• wolfssl/wolfcrypt/src/dilithium.c

  Line 9730 in bc68819

  ret = SetAsymKeyDerPublic(key->p, pubKeyLen, output, len, keytype,

The SetAsymDerPublic() is defined in the asn.c (L:12043) file and it is meant to be used for ED curves, not for generic ASN.1 (i.e., the documentation refers to RFC8410). The buffer size for the dataASN is set to edPubKeyASN_Length, which does not work for Dilithium.

Proposed Resolution:

1. Change the name of the function to be specific for ED curves, and
2. Fix the use in MlDsa/Dilithium code.

[philljj]

Hi @opencrypto,

Thank you for the report, I will look at this.

Thanks,
Jordan

[philljj]

Hi @opencrypto,

The documentation and variable names around SetAsymKeyDerPublic() are outdated, and we'll open a PR to update this.

The SetAsymKeyDerPublic() is a generic function we use for sphincs, dilithium, falcon, Ed, etc. The edPubKeyASN_Length is just the number of ASN items in the template for this type of pub key.

Sorry for the confusion!

Thanks,
Jordan

[dgarske]

#8009