6. CMOX_EDDSA

6.1. CMOX ECC EDDSA PUBLIC METHODS

group CMOX_ECC_EDDSA_PUBLIC_METHODS

Functions

cmox_ecc_retval_t cmox_eddsa_keyGen ( cmox_ecc_handle_t * P_pEccCtx , const cmox_ecc_impl_t P_CurveParams , const uint8_t * P_pRandom , size_t P_RandomLen , uint8_t * P_pPrivKey , size_t * P_pPrivKeyLen , uint8_t * P_pPubKey , size_t * P_pPubKeyLen )

Generate private and public keys to use with EDDSA.

Note

If P_RandomLen is not enough, an error is returned and P_pPrivKeyLen contains the minimum number of bytes of random to provide (and is also half the minimum length of P_pPrivKey), while P_pPubKeyLen contains the minimum length of P_pPubKey.

Parameters :

  • P_pEccCtx – [in] Context for ECC operations

  • P_CurveParams – [in] Curve Parameters and point functions This parameter can be one of the following:

    • CMOX_ECC_ED25519_HIGHMEM

    • CMOX_ECC_ED25519_OPT_LOWMEM

    • CMOX_ECC_ED25519_OPT_HIGHMEM

    • CMOX_ECC_ED448_LOWMEM

    • CMOX_ECC_ED448_HIGHMEM

  • P_pRandom – [in] Buffer of random bytes

  • P_RandomLen – [in] Byte length of the random buffer

  • P_pPrivKey – [out] Buffer with the private key, whose first half will be the secret value and the second half will contain the public key

  • P_pPrivKeyLen – [out] Byte length of the private key

  • P_pPubKey – [out] Buffer with the public key

  • P_pPubKeyLen – [out] Byte length of the public key

Return values :

  • CMOX_ECC_SUCCESS – Everything OK

  • CMOX_ECC_ERR_MATHCURVE_MISMATCH – Mathematical function set is not compatible with current ECC curve

  • CMOX_ECC_ERR_ALGOCURVE_MISMATCH – Curve is not compatible with current functionality

  • CMOX_ECC_ERR_BAD_PARAMETERS – Some NULL/wrong/empty parameter or Construct API not called

  • CMOX_ECC_ERR_WRONG_RANDOM – Random material too short or not valid for the functionality

  • CMOX_ECC_ERR_MEMORY_FAIL – Not enough memory

  • CMOX_ECC_ERR_INTERNAL – Something went wrong during internal computations (e.g. hash)

cmox_ecc_retval_t cmox_eddsa_sign ( cmox_ecc_handle_t * P_pEccCtx , const cmox_ecc_impl_t P_CurveParams , const uint8_t * P_pPrivKey , size_t P_PrivKeyLen , const uint8_t * P_pMessage , size_t P_MessageLen , uint8_t * P_pSignature , size_t * P_pSignatureLen )

Generate a signature, using EDDSA.

Parameters :

  • P_pEccCtx – [in] Context for ECC operations

  • P_CurveParams – [in] Curve Parameters and point functions This parameter can be one of the following:

    • CMOX_ECC_ED25519_HIGHMEM

    • CMOX_ECC_ED25519_OPT_LOWMEM

    • CMOX_ECC_ED25519_OPT_HIGHMEM

    • CMOX_ECC_ED448_LOWMEM

    • CMOX_ECC_ED448_HIGHMEM

  • P_pPrivKey – [in] Buffer with the private key, whose first half is the secret value and the second half contains the public key

  • P_PrivKeyLen – [in] Byte length of the private key

  • P_pMessage – [in] Buffer with the message to sign

  • P_MessageLen – [in] Byte length of the message

  • P_pSignature – [out] Buffer with the signature (concatenation of R and S)

  • P_pSignatureLen – [out] Byte length of the signature

Return values :

  • CMOX_ECC_SUCCESS – Everything OK

  • CMOX_ECC_ERR_MATHCURVE_MISMATCH – Mathematical function set is not compatible with current ECC curve

  • CMOX_ECC_ERR_ALGOCURVE_MISMATCH – Curve is not compatible with current functionality

  • CMOX_ECC_ERR_BAD_PARAMETERS – Some NULL/wrong/empty parameter or Construct API not called

  • CMOX_ECC_ERR_MEMORY_FAIL – Not enough memory

  • CMOX_ECC_ERR_INTERNAL – Something went wrong during internal computations (e.g. hash)

cmox_ecc_retval_t cmox_eddsa_verify ( cmox_ecc_handle_t * P_pEccCtx , const cmox_ecc_impl_t P_CurveParams , const uint8_t * P_pPubKey , size_t P_PubKeyLen , const uint8_t * P_pMessage , size_t P_MessageLen , const uint8_t * P_pSignature , size_t P_SignatureLen , uint32_t * P_pFaultCheck )

Verify a signature, using EDDSA.

Note

P_pFaultCheck value, if the parameter is provided, MUST be checked to be equal to the retval, and both MUST be equal to the successful value. P_pFaultCheck MUST be checked only if the main result is successful, and has no relevance if the main result is not successful. Every comparison (both for the return value and for P_pFaultCheck) must be done against the success value, and not comparing the value with the failure value. Indeed, in presence of faults, especially P_pFaultCheck, could be a dirty value.

Parameters :

  • P_pEccCtx – [in] Context for ECC operations

  • P_CurveParams – [in] Curve Parameters and point functions This parameter can be one of the following:

    • CMOX_ECC_ED25519_HIGHMEM

    • CMOX_ECC_ED25519_OPT_LOWMEM

    • CMOX_ECC_ED25519_OPT_HIGHMEM

    • CMOX_ECC_ED448_LOWMEM

    • CMOX_ECC_ED448_HIGHMEM

  • P_pPubKey – [in] Buffer with the public key

  • P_PubKeyLen – [in] Byte length of the public key

  • P_pMessage – [in] Buffer with the message to verify

  • P_MessageLen – [in] Byte length of the message

  • P_pSignature – [in] Buffer with the signature (concatenation of R and S)

  • P_SignatureLen – [in] Byte length of the signature

  • P_pFaultCheck – [out] Optional value to check, together with the retval, to verify if some fault happened

Return values :

  • CMOX_ECC_AUTH_SUCCESS – Signature verified

  • CMOX_ECC_AUTH_FAIL – Signature NOT verified

  • CMOX_ECC_ERR_MATHCURVE_MISMATCH – Mathematical function set is not compatible with current ECC curve

  • CMOX_ECC_ERR_ALGOCURVE_MISMATCH – Curve is not compatible with current functionality

  • CMOX_ECC_ERR_BAD_PARAMETERS – Some NULL/wrong/empty parameter or Construct API not called

  • CMOX_ECC_ERR_MEMORY_FAIL – Not enough memory

  • CMOX_ECC_ERR_INTERNAL – Something went wrong during internal computations (e.g. hash)

  • CMOX_ECC_ERR_INVALID_SIGNATURE – Input signature corrupted or not in the expected format

  • CMOX_ECC_ERR_INVALID_PUBKEY – Public key not in a valid format