1. CMOX_RSA

void cmox_rsa_construct ( cmox_rsa_handle_t * P_pRsaCtx , const cmox_math_funcs_t P_Math , const cmox_modexp_func_t P_Modexp , uint8_t * P_pBuf , size_t P_BufLen )

Mandatory function to set Low Level Mathematical Functions, and working memory buffer, for RSA.

Parameters :

P_pRsaCtx – [inout] Context for RSA operations
P_Math – [in] Structure pointer with the Low-level Mathematical functions This parameter can be one of the following:
- CMOX_MATH_FUNCS_SMALL
- CMOX_MATH_FUNCS_FAST
P_Modexp – [in] Structure pointer with the Modular Exponentiation function This parameter can be one of the following:
- CMOX_MODEXP_PUBLIC
- CMOX_MODEXP_PRIVATE_LOWMEM
- CMOX_MODEXP_PRIVATE_MIDMEM
- CMOX_MODEXP_PRIVATE_HIGHMEM
P_pBuf – [in] The preallocated static buffer that will be used
P_BufLen – [in] The size in bytes of the P_pBuf buffer

void cmox_rsa_cleanup ( cmox_rsa_handle_t * P_pRsaCtx )

Clean the RSA context and the internal temporary buffer.

Parameters :: P_pRsaCtx – [inout] Context for RSA operations

cmox_rsa_retval_t cmox_rsa_setKey ( cmox_rsa_key_t * P_pKey , const uint8_t * P_pModulus , size_t P_ModulusLen , const uint8_t * P_pExp , size_t P_ExpLen )

Set the key (public or private) in the key structure.

Parameters :

P_pKey – [out] Key to set
P_pModulus – [in] Modulus
P_ModulusLen – [in] Modulus Length (in Bytes)
P_pExp – [in] Exponent (private or public)
P_ExpLen – [in] Exponent Length (in Bytes)

Return values :

CMOX_RSA_SUCCESS –
CMOX_RSA_ERR_BAD_PARAMETER –

cmox_rsa_retval_t cmox_rsa_setKeyCRT ( cmox_rsa_key_t * P_pPrivKey , size_t P_ModulusBitLen , const uint8_t * P_pExpP , size_t P_ExpPLen , const uint8_t * P_pExpQ , size_t P_ExpQLen , const uint8_t * P_pP , size_t P_PLen , const uint8_t * P_pQ , size_t P_QLen , const uint8_t * P_pIq , size_t P_IqLen )

Set the private CRT key in the key structure.

Parameters :

P_pPrivKey – [out] Private Key to set
P_ModulusBitLen – [in] Modulus Length (in bits)
P_pExpP – [in] Secret exponent (mod P) dP
P_ExpPLen – [in] dP Length (in Bytes)
P_pExpQ – [in] Secret exponent (mod Q) dQ
P_ExpQLen – [in] dQ Length (in Bytes)
P_pP – [in] First secret prime P
P_PLen – [in] P Length (in Bytes)
P_pQ – [in] Second secret prime Q
P_QLen – [in] Q Length (in Bytes)
P_pIq – [in] Inverse of Q (mod P) invQ
P_IqLen – [in] invQ Length (in Bytes)

Return values :

CMOX_RSA_SUCCESS –
CMOX_RSA_ERR_BAD_PARAMETER –

cmox_rsa_retval_t cmox_rsa_setKeyCRTwithFACM ( cmox_rsa_key_t * P_pPrivKey , size_t P_ModulusBitLen , const uint8_t * P_pExpP , size_t P_ExpPLen , const uint8_t * P_pExpQ , size_t P_ExpQLen , const uint8_t * P_pP , size_t P_PLen , const uint8_t * P_pQ , size_t P_QLen , const uint8_t * P_pIq , size_t P_IqLen , const uint8_t * P_pPubKey , size_t P_PubKeyLen )

Set the private CRT key in the key structure, enabling the Fault Attacks Countermeasure.

Note

This function enables the protection against the Bellcore attack for RSA-CRT computation. This countermeasure is useful to protect RSA-CRT using PKCS#1 v1.5 for Signature Creation. Indeed, PKCS#1 v2.2 Signature Creation is not vulnerable because of the presence of an input random, and Decryption processes (both for PKCS#1 v1.5 and v2.2) are not vulnerable because the plaintext is not returned if not correct (therefore not exploitable by an attacker).

Parameters :

P_pPrivKey – [out] Private Key to set
P_ModulusBitLen – [in] Modulus Length (in bits)
P_pExpP – [in] Secret exponent (mod P) dP
P_ExpPLen – [in] dP Length (in Bytes)
P_pExpQ – [in] Secret exponent (mod Q) dQ
P_ExpQLen – [in] dQ Length (in Bytes)
P_pP – [in] First secret prime P
P_PLen – [in] P Length (in Bytes)
P_pQ – [in] Second secret prime Q
P_QLen – [in] Q Length (in Bytes)
P_pIq – [in] Inverse of Q (mod P) invQ
P_IqLen – [in] invQ Length (in Bytes)
P_pPubKey – [in] Public Key
P_PubKeyLen – [in] Public Key Length (in Bytes)

Return values :

CMOX_RSA_SUCCESS –
CMOX_RSA_ERR_BAD_PARAMETER –

1. CMOX_RSA ¶

1.1. RSA public method prototypes ¶