wolfCrypt Init and Cleanup

Functions
int	wc_HashGetOID (enum wc_HashType hash_type)
	This function will return the OID for the wc_HashType provided. More...
int	wc_HashGetDigestSize (enum wc_HashType hash_type)
	This function returns the size of the digest (output) for a hash_type. The returns size is used to make sure the output buffer provided to wc_Hash is large enough. More...
int	wc_Hash (enum wc_HashType hash_type, const byte *data, word32 data_len, byte *hash, word32 hash_len)
	This function performs a hash on the provided data buffer and returns it in the hash buffer provided. More...
int	wolfCrypt_Init (void)
	Used to initialize resources used by wolfCrypt. More...
int	wolfCrypt_Cleanup (void)
	Used to clean up resources used by wolfCrypt. More...

Detailed Description

Function Documentation

wc_Hash()

int wc_Hash	(	enum wc_HashType	hash_type,
		const byte *	data,
		word32	data_len,
		byte *	hash,
		word32	hash_len
	)

This function performs a hash on the provided data buffer and returns it in the hash buffer provided.

Returns

0 Success, else error (such as BAD_FUNC_ARG or BUFFER_E).

Parameters

hash_type	A hash type from the “enum wc_HashType” such as “WC_HASH_TYPE_SHA256”.
data	Pointer to buffer containing the data to hash.
data_len	Length of the data buffer.
hash	Pointer to buffer used to output the final hash to.
hash_len	Length of the hash buffer.

Example

enum wc_HashType hash_type = WC_HASH_TYPE_SHA256;
int hash_len = wc_HashGetDigestSize(hash_type);
if (hash_len > 0) {
    int ret = wc_Hash(hash_type, data, data_len, hash_data, hash_len);
    if(ret == 0) {
        // Success
    }
}

See also

wc_HashGetDigestSize

wc_HashGetDigestSize()

int wc_HashGetDigestSize

(

enum wc_HashType

hash_type

)

This function returns the size of the digest (output) for a hash_type. The returns size is used to make sure the output buffer provided to wc_Hash is large enough.

Returns

Success A positive return value indicates the digest size for the hash.

Error Returns HASH_TYPE_E if hash_type is not supported.

Failure Returns BAD_FUNC_ARG if an invalid hash_type was used.

Parameters

hash_type

A hash type from the “enum wc_HashType” such as “WC_HASH_TYPE_SHA256”.

Example

int hash_len = wc_HashGetDigestSize(hash_type);
if (hash_len <= 0) {
WOLFSSL_MSG("Invalid hash type/len");
return BAD_FUNC_ARG;
}

See also

wc_Hash

wc_HashGetOID()

int wc_HashGetOID

(

enum wc_HashType

hash_type

)

This function will return the OID for the wc_HashType provided.

Returns

OID returns value greater than 0

HASH_TYPE_E hash type not supported.

BAD_FUNC_ARG one of the provided arguments is incorrect.

Parameters

hash_type

A hash type from the “enum wc_HashType” such as “WC_HASH_TYPE_SHA256”.

Example

enum wc_HashType hash_type = WC_HASH_TYPE_SHA256;
int oid = wc_HashGetOID(hash_type);
if (oid > 0) {
    // Success
}

See also

wc_HashGetDigestSize

wc_Hash

wolfCrypt_Cleanup()

int wolfCrypt_Cleanup

(

void

)

Used to clean up resources used by wolfCrypt.

Returns

0 upon success.

<0 upon failure of cleaning up resources.

Parameters

none	No parameters.

Example

...
if (wolfCrypt_Cleanup() != 0) {
    WOLFSSL_MSG("Error with wolfCrypt_Cleanup call");
}

See also

wolfCrypt_Init

wolfCrypt_Init()

int wolfCrypt_Init

(

void

)

Used to initialize resources used by wolfCrypt.

Returns

0 upon success.

<0 upon failure of init resources.

Parameters

none	No parameters.

Example

...
if (wolfCrypt_Init() != 0) {
    WOLFSSL_MSG("Error with wolfCrypt_Init call");
}

See also

wolfCrypt_Cleanup