Functions
int	wc_HmacSetKey (Hmac hmac, int type, const byte key, word32 keySz)
	This function initializes an Hmac object, setting its encryption type, key and HMAC length. More...

int	wc_HmacUpdate (Hmac hmac, const byte in, word32 sz)
	This function updates the message to authenticate using HMAC. It should be called after the Hmac object has been initialized with wc_HmacSetKey. This function may be called multiple times to update the message to hash. After calling wc_HmacUpdate as desired, one should call wc_HmacFinal to obtain the final authenticated message tag. More...

int	wc_HmacFinal (Hmac hmac, byte out)
	This function computes the final hash of an Hmac object's message. More...

int	wolfSSL_GetHmacMaxSize (void)
	This function returns the largest HMAC digest size available based on the configured cipher suites. More...

int	wc_HKDF (int type, const byte inKey, word32 inKeySz, const byte salt, word32 saltSz, const byte info, word32 infoSz, byte out, word32 outSz)
	This function provides access to a HMAC Key Derivation Function (HKDF). It utilizes HMAC to convert inKey, with an optional salt and optional info into a derived key, which it stores in out. The hash type defaults to MD5 if 0 or NULL is given. More...

int	wc_HKDF_Extract (int type, const byte salt, word32 saltSz, const byte inKey, word32 inKeySz, byte *out)
	This function provides access to a HMAC Key Derivation Function (HKDF). It utilizes HMAC to convert inKey, with an optional salt into a derived key, which it stores in out. The hash type defaults to MD5 if 0 or NULL is given. More...

int	wc_HKDF_Extract_ex (int type, const byte salt, word32 saltSz, const byte inKey, word32 inKeySz, byte out, void heap, int devId)
	This function provides access to a HMAC Key Derivation Function (HKDF). It utilizes HMAC to convert inKey, with an optional salt into a derived key, which it stores in out. The hash type defaults to MD5 if 0 or NULL is given. This is the _ex version adding heap hint and device identifier. More...

int	wc_HKDF_Expand (int type, const byte inKey, word32 inKeySz, const byte info, word32 infoSz, byte *out, word32 outSz)
	This function provides access to a HMAC Key Derivation Function (HKDF). It utilizes HMAC to convert inKey, with optional info into a derived key, which it stores in out. The hash type defaults to MD5 if 0 or NULL is given. More...

int	wc_HKDF_Expand_ex (int type, const byte inKey, word32 inKeySz, const byte info, word32 infoSz, byte out, word32 outSz, void heap, int devId)
	This function provides access to a HMAC Key Derivation Function (HKDF). It utilizes HMAC to convert inKey, with optional info into a derived key, which it stores in out. The hash type defaults to MD5 if 0 or NULL is given. This is the _ex version adding heap hint and device identifier. More...

int	wc_Tls13_HKDF_Extract (byte prk, const byte salt, word32 saltLen, byte *ikm, word32 ikmLen, int digest)
	This function provides access to RFC 5869 HMAC-based Extract-and-Expand Key Derivation Function (HKDF) for TLS v1.3 key derivation. More...

int	wc_Tls13_HKDF_Extract_ex (byte prk, const byte salt, word32 saltLen, byte ikm, word32 ikmLen, int digest, void heap, int devId)
	This function provides access to RFC 5869 HMAC-based Extract-and-Expand Key Derivation Function (HKDF) for TLS v1.3 key derivation. This is the _ex version adding heap hint and device identifier. More...

int	wc_Tls13_HKDF_Expand_Label_ex (byte okm, word32 okmLen, const byte prk, word32 prkLen, const byte protocol, word32 protocolLen, const byte label, word32 labelLen, const byte info, word32 infoLen, int digest, void heap, int devId)
	Expand data using HMAC, salt and label and info. TLS v1.3 defines this function for key derivation. This is the _ex version adding heap hint and device identifier. More...

int	wc_Tls13_HKDF_Expand_Label (byte okm, word32 okmLen, const byte prk, word32 prkLen, const byte protocol, word32 protocolLen, const byte label, word32 labelLen, const byte *info, word32 infoLen, int digest)
	Expand data using HMAC, salt and label and info. TLS v1.3 defines this function for key derivation. This is the _ex version adding heap hint and device identifier. More...

int	wc_Tls13_HKDF_Expand_Label_Alloc (byte okm, word32 okmLen, const byte prk, word32 prkLen, const byte protocol, word32 protocolLen, const byte label, word32 labelLen, const byte info, word32 infoLen, int digest, void heap)
	This functions is very similar to wc_Tls13_HKDF_Expand_Label(), but it allocates memory if the stack space usually used isn't enough. Expand data using HMAC, salt and label and info. TLS v1.3 defines this function for key derivation. This is the _ex version adding heap hint and device identifier. More...

Detailed Description

Function Documentation

◆ wc_HKDF()

int wc_HKDF	(	int	type,
		const byte *	inKey,
		word32	inKeySz,
		const byte *	salt,
		word32	saltSz,
		const byte *	info,
		word32	infoSz,
		byte *	out,
		word32	outSz
	)

This function provides access to a HMAC Key Derivation Function (HKDF). It utilizes HMAC to convert inKey, with an optional salt and optional info into a derived key, which it stores in out. The hash type defaults to MD5 if 0 or NULL is given.

The HMAC configure option is –enable-hmac (on by default) or if building sources directly HAVE_HKDF

Returns: 0 Returned upon successfully generating a key with the given inputs; BAD_FUNC_ARG Returned if an invalid hash type is given (see type param); MEMORY_E Returned if there is an error allocating memory; HMAC_MIN_KEYLEN_E May be returned when using a FIPS implementation and the key length specified is shorter than the minimum acceptable FIPS standard

Parameters

type	hash type to use for the HKDF. Valid types are: WC_MD5, WC_SHA, WC_SHA256, WC_SHA384, WC_SHA512, WC_SHA3_224, WC_SHA3_256, WC_SHA3_384 or WC_SHA3_512
inKey	pointer to the buffer containing the key to use for KDF
inKeySz	length of the input key
salt	pointer to a buffer containing an optional salt. Use NULL instead if not using a salt
saltSz	length of the salt. Use 0 if not using a salt
info	pointer to a buffer containing optional additional info. Use NULL if not appending extra info
infoSz	length of additional info. Use 0 if not using additional info
out	pointer to the buffer in which to store the derived key
outSz	space available in the output buffer to store the generated key

Example

byte key[] = { // initialize with key };
byte salt[] = { // initialize with salt };
byte derivedKey[MAX_DIGEST_SIZE];
 
int ret = wc_HKDF(WC_SHA512, key, sizeof(key), salt, sizeof(salt),
NULL, 0, derivedKey, sizeof(derivedKey));
if ( ret != 0 ) {
    // error generating derived key
}

See also: wc_HmacSetKey

◆ wc_HKDF_Expand()

int wc_HKDF_Expand	(	int	type,
		const byte *	inKey,
		word32	inKeySz,
		const byte *	info,
		word32	infoSz,
		byte *	out,
		word32	outSz
	)

This function provides access to a HMAC Key Derivation Function (HKDF). It utilizes HMAC to convert inKey, with optional info into a derived key, which it stores in out. The hash type defaults to MD5 if 0 or NULL is given.

The HMAC configure option is –enable-hmac (on by default) or if building sources directly HAVE_HKDF

Returns: 0 Returned upon successfully generating a key with the given inputs; BAD_FUNC_ARG Returned if an invalid hash type is given (see type param); MEMORY_E Returned if there is an error allocating memory; HMAC_MIN_KEYLEN_E May be returned when using a FIPS implementation and the key length specified is shorter than the minimum acceptable FIPS standard

Parameters

type	hash type to use for the HKDF. Valid types are: WC_MD5, WC_SHA, WC_SHA256, WC_SHA384, WC_SHA512, WC_SHA3_224, WC_SHA3_256, WC_SHA3_384 or WC_SHA3_512
inKey	pointer to the buffer containing the key to use for KDF
inKeySz	length of the input key
info	pointer to a buffer containing optional additional info. Use NULL if not appending extra info
infoSz	length of additional info. Use 0 if not using additional info
out	pointer to the buffer in which to store the derived key
outSz	space available in the output buffer to store the generated key

Example

byte key[] = { // initialize with key };
byte salt[] = { // initialize with salt };
byte derivedKey[MAX_DIGEST_SIZE];
 
int ret = wc_HKDF_Expand(WC_SHA512, key, sizeof(key), NULL, 0,
    derivedKey, sizeof(derivedKey));
if ( ret != 0 ) {
    // error generating derived key
}

See also: wc_HKDF; wc_HKDF_Extract; wc_HKDF_Extract_ex; wc_HKDF_Expand_ex

◆ wc_HKDF_Expand_ex()

int wc_HKDF_Expand_ex	(	int	type,
		const byte *	inKey,
		word32	inKeySz,
		const byte *	info,
		word32	infoSz,
		byte *	out,
		word32	outSz,
		void *	heap,
		int	devId
	)

This function provides access to a HMAC Key Derivation Function (HKDF). It utilizes HMAC to convert inKey, with optional info into a derived key, which it stores in out. The hash type defaults to MD5 if 0 or NULL is given. This is the _ex version adding heap hint and device identifier.

The HMAC configure option is –enable-hmac (on by default) or if building sources directly HAVE_HKDF

Returns: 0 Returned upon successfully generating a key with the given inputs; BAD_FUNC_ARG Returned if an invalid hash type is given (see type param); MEMORY_E Returned if there is an error allocating memory; HMAC_MIN_KEYLEN_E May be returned when using a FIPS implementation and the key length specified is shorter than the minimum acceptable FIPS standard

Parameters

type	hash type to use for the HKDF. Valid types are: WC_MD5, WC_SHA, WC_SHA256, WC_SHA384, WC_SHA512, WC_SHA3_224, WC_SHA3_256, WC_SHA3_384 or WC_SHA3_512
inKey	pointer to the buffer containing the key to use for KDF
inKeySz	length of the input key
info	pointer to a buffer containing optional additional info. Use NULL if not appending extra info
infoSz	length of additional info. Use 0 if not using additional info
out	pointer to the buffer in which to store the derived key
outSz	space available in the output buffer to store the generated key
heap	heap hint to use for memory. Can be NULL
devId	ID to use with crypto callbacks or async hardware. Set to INVALID_DEVID (-2) if not used

Example

byte key[] = { // initialize with key };
byte salt[] = { // initialize with salt };
byte derivedKey[MAX_DIGEST_SIZE];
 
int ret = wc_HKDF_Expand_ex(WC_SHA512, key, sizeof(key), NULL, 0,
    derivedKey, sizeof(derivedKey), NULL, INVALID_DEVID);
if ( ret != 0 ) {
    // error generating derived key
}

See also: wc_HKDF; wc_HKDF_Extract; wc_HKDF_Extract_ex; wc_HKDF_Expand

◆ wc_HKDF_Extract()

int wc_HKDF_Extract	(	int	type,
		const byte *	salt,
		word32	saltSz,
		const byte *	inKey,
		word32	inKeySz,
		byte *	out
	)

This function provides access to a HMAC Key Derivation Function (HKDF). It utilizes HMAC to convert inKey, with an optional salt into a derived key, which it stores in out. The hash type defaults to MD5 if 0 or NULL is given.

The HMAC configure option is –enable-hmac (on by default) or if building sources directly HAVE_HKDF

Returns: 0 Returned upon successfully generating a key with the given inputs; BAD_FUNC_ARG Returned if an invalid hash type is given (see type param); MEMORY_E Returned if there is an error allocating memory; HMAC_MIN_KEYLEN_E May be returned when using a FIPS implementation and the key length specified is shorter than the minimum acceptable FIPS standard

Parameters

type	hash type to use for the HKDF. Valid types are: WC_MD5, WC_SHA, WC_SHA256, WC_SHA384, WC_SHA512, WC_SHA3_224, WC_SHA3_256, WC_SHA3_384 or WC_SHA3_512
salt	pointer to a buffer containing an optional salt. Use NULL instead if not using a salt
saltSz	length of the salt. Use 0 if not using a salt
inKey	pointer to the buffer containing the key to use for KDF
inKeySz	length of the input key
out	pointer to the buffer in which to store the derived key

Example

byte key[] = { // initialize with key };
byte salt[] = { // initialize with salt };
byte derivedKey[MAX_DIGEST_SIZE];
 
int ret = wc_HKDF_Extract(WC_SHA512, salt, sizeof(salt), key, sizeof(key),
    derivedKey);
if ( ret != 0 ) {
    // error generating derived key
}

See also: wc_HKDF; wc_HKDF_Extract_ex; wc_HKDF_Expand; wc_HKDF_Expand_ex

◆ wc_HKDF_Extract_ex()

int wc_HKDF_Extract_ex	(	int	type,
		const byte *	salt,
		word32	saltSz,
		const byte *	inKey,
		word32	inKeySz,
		byte *	out,
		void *	heap,
		int	devId
	)

This function provides access to a HMAC Key Derivation Function (HKDF). It utilizes HMAC to convert inKey, with an optional salt into a derived key, which it stores in out. The hash type defaults to MD5 if 0 or NULL is given. This is the _ex version adding heap hint and device identifier.

The HMAC configure option is –enable-hmac (on by default) or if building sources directly HAVE_HKDF

Returns: 0 Returned upon successfully generating a key with the given inputs; BAD_FUNC_ARG Returned if an invalid hash type is given (see type param); MEMORY_E Returned if there is an error allocating memory; HMAC_MIN_KEYLEN_E May be returned when using a FIPS implementation and the key length specified is shorter than the minimum acceptable FIPS standard

Parameters

type	hash type to use for the HKDF. Valid types are: WC_MD5, WC_SHA, WC_SHA256, WC_SHA384, WC_SHA512, WC_SHA3_224, WC_SHA3_256, WC_SHA3_384 or WC_SHA3_512
salt	pointer to a buffer containing an optional salt. Use NULL instead if not using a salt
saltSz	length of the salt. Use 0 if not using a salt
inKey	pointer to the buffer containing the key to use for KDF
inKeySz	length of the input key
out	pointer to the buffer in which to store the derived key
heap	heap hint to use for memory. Can be NULL
devId	ID to use with crypto callbacks or async hardware. Set to INVALID_DEVID (-2) if not used

Example

byte key[] = { // initialize with key };
byte salt[] = { // initialize with salt };
byte derivedKey[MAX_DIGEST_SIZE];
 
int ret = wc_HKDF_Extract_ex(WC_SHA512, salt, sizeof(salt), key, sizeof(key),
    derivedKey, NULL, INVALID_DEVID);
if ( ret != 0 ) {
    // error generating derived key
}

See also: wc_HKDF; wc_HKDF_Extract; wc_HKDF_Expand; wc_HKDF_Expand_ex

◆ wc_HmacFinal()

int wc_HmacFinal	(	Hmac *	hmac,
		byte *	out
	)

This function computes the final hash of an Hmac object's message.

Returns: 0 Returned on successfully computing the final hash; MEMORY_E Returned if there is an error allocating memory for use with a hashing algorithm

Parameters

hmac	pointer to the Hmac object for which to calculate the final hash
hash	pointer to the buffer in which to store the final hash. Should have room available as required by the hashing algorithm chosen

Example

Hmac hmac;
byte hash[MD5_DIGEST_SIZE];
// initialize hmac with MD5 as type
// wc_HmacUpdate() with messages
 
if (wc_HmacFinal(&hmac, hash) != 0) {
    // error computing hash
}

See also: wc_HmacSetKey; wc_HmacUpdate

◆ wc_HmacSetKey()

int wc_HmacSetKey	(	Hmac *	hmac,
		int	type,
		const byte *	key,
		word32	keySz
	)

This function initializes an Hmac object, setting its encryption type, key and HMAC length.

Returns: 0 Returned on successfully initializing the Hmac object; BAD_FUNC_ARG Returned if the input type is invalid (see type param); MEMORY_E Returned if there is an error allocating memory for the structure to use for hashing; HMAC_MIN_KEYLEN_E May be returned when using a FIPS implementation and the key length specified is shorter than the minimum acceptable FIPS standard

Parameters

hmac	pointer to the Hmac object to initialize
type	type specifying which encryption method the Hmac object should use. Valid options are: WC_MD5, WC_SHA, WC_SHA256, WC_SHA384, WC_SHA512, WC_SHA3_224, WC_SHA3_256, WC_SHA3_384 or WC_SHA3_512
key	pointer to a buffer containing the key with which to initialize the Hmac object
length	length of the key

Example

Hmac hmac;
byte key[] = { // initialize with key to use for encryption };
if (wc_HmacSetKey(&hmac, WC_MD5, key, sizeof(key)) != 0) {
    // error initializing Hmac object
}

See also: wc_HmacUpdate; wc_HmacFinal

◆ wc_HmacUpdate()

int wc_HmacUpdate	(	Hmac *	hmac,
		const byte *	in,
		word32	sz
	)

This function updates the message to authenticate using HMAC. It should be called after the Hmac object has been initialized with wc_HmacSetKey. This function may be called multiple times to update the message to hash. After calling wc_HmacUpdate as desired, one should call wc_HmacFinal to obtain the final authenticated message tag.

Returns: 0 Returned on successfully updating the message to authenticate; MEMORY_E Returned if there is an error allocating memory for use with a hashing algorithm

Parameters

hmac	pointer to the Hmac object for which to update the message
msg	pointer to the buffer containing the message to append
length	length of the message to append

Example

Hmac hmac;
byte msg[] = { // initialize with message to authenticate };
byte msg2[] = { // initialize with second half of message };
// initialize hmac
if( wc_HmacUpdate(&hmac, msg, sizeof(msg)) != 0) {
    // error updating message
}
if( wc_HmacUpdate(&hmac, msg2, sizeof(msg)) != 0) {
    // error updating with second message
}

See also: wc_HmacSetKey; wc_HmacFinal

◆ wc_Tls13_HKDF_Expand_Label()

int wc_Tls13_HKDF_Expand_Label	(	byte *	okm,
		word32	okmLen,
		const byte *	prk,
		word32	prkLen,
		const byte *	protocol,
		word32	protocolLen,
		const byte *	label,
		word32	labelLen,
		const byte *	info,
		word32	infoLen,
		int	digest
	)

Expand data using HMAC, salt and label and info. TLS v1.3 defines this function for key derivation. This is the _ex version adding heap hint and device identifier.

Returns: 0 Returned upon successfully generating a key with the given inputs; BAD_FUNC_ARG Returned if an invalid hash type is given (see type param); MEMORY_E Returned if there is an error allocating memory; HMAC_MIN_KEYLEN_E May be returned when using a FIPS implementation and the key length specified is shorter than the minimum acceptable FIPS standard

Parameters

okm	Generated pseudorandom key - output key material.
okmLen	Length of generated pseudorandom key - output key material.
prk	Salt - pseudo-random key.
prkLen	Length of the salt - pseudo-random key.
protocol	TLS protocol label.
protocolLen	Length of the TLS protocol label.
info	Information to expand.
infoLen	Length of the information.
digest	Hash type to use for the HKDF. Valid types are: WC_SHA256, WC_SHA384 or WC_SHA512

See also: wc_HKDF; wc_HKDF_Extract; wc_HKDF_Extract_ex; wc_HKDF_Expand; wc_Tls13_HKDF_Expand_Label_ex; wc_Tls13_HKDF_Expand_Label_Alloc

◆ wc_Tls13_HKDF_Expand_Label_Alloc()

int wc_Tls13_HKDF_Expand_Label_Alloc	(	byte *	okm,
		word32	okmLen,
		const byte *	prk,
		word32	prkLen,
		const byte *	protocol,
		word32	protocolLen,
		const byte *	label,
		word32	labelLen,
		const byte *	info,
		word32	infoLen,
		int	digest,
		void *	heap
	)

This functions is very similar to wc_Tls13_HKDF_Expand_Label(), but it allocates memory if the stack space usually used isn't enough. Expand data using HMAC, salt and label and info. TLS v1.3 defines this function for key derivation. This is the _ex version adding heap hint and device identifier.

Returns: 0 Returned upon successfully generating a key with the given inputs; BAD_FUNC_ARG Returned if an invalid hash type is given (see type param); MEMORY_E Returned if there is an error allocating memory; HMAC_MIN_KEYLEN_E May be returned when using a FIPS implementation and the key length specified is shorter than the minimum acceptable FIPS standard

Parameters

okm	Generated pseudorandom key - output key material.
okmLen	Length of generated pseudorandom key - output key material.
prk	Salt - pseudo-random key.
prkLen	Length of the salt - pseudo-random key.
protocol	TLS protocol label.
protocolLen	Length of the TLS protocol label.
info	Information to expand.
infoLen	Length of the information.
digest	Hash type to use for the HKDF. Valid types are: WC_SHA256, WC_SHA384 or WC_SHA512
heap	Heap hint to use for memory. Can be NULL

See also: wc_HKDF; wc_HKDF_Extract; wc_HKDF_Extract_ex; wc_HKDF_Expand; wc_Tls13_HKDF_Expand_Label; wc_Tls13_HKDF_Expand_Label_ex

◆ wc_Tls13_HKDF_Expand_Label_ex()

int wc_Tls13_HKDF_Expand_Label_ex	(	byte *	okm,
		word32	okmLen,
		const byte *	prk,
		word32	prkLen,
		const byte *	protocol,
		word32	protocolLen,
		const byte *	label,
		word32	labelLen,
		const byte *	info,
		word32	infoLen,
		int	digest,
		void *	heap,
		int	devId
	)

Expand data using HMAC, salt and label and info. TLS v1.3 defines this function for key derivation. This is the _ex version adding heap hint and device identifier.

Returns: 0 Returned upon successfully generating a key with the given inputs; BAD_FUNC_ARG Returned if an invalid hash type is given (see type param); MEMORY_E Returned if there is an error allocating memory; HMAC_MIN_KEYLEN_E May be returned when using a FIPS implementation and the key length specified is shorter than the minimum acceptable FIPS standard

Parameters

okm	Generated pseudorandom key - output key material.
okmLen	Length of generated pseudorandom key - output key material.
prk	Salt - pseudo-random key.
prkLen	Length of the salt - pseudo-random key.
protocol	TLS protocol label.
protocolLen	Length of the TLS protocol label.
info	Information to expand.
infoLen	Length of the information.
digest	Hash type to use for the HKDF. Valid types are: WC_SHA256, WC_SHA384 or WC_SHA512
heap	Heap hint to use for memory. Can be NULL
devId	ID to use with crypto callbacks or async hardware. Set to INVALID_DEVID (-2) if not used

See also: wc_HKDF; wc_HKDF_Extract; wc_HKDF_Extract_ex; wc_HKDF_Expand; wc_Tls13_HKDF_Expand_Label; wc_Tls13_HKDF_Expand_Label_Alloc

◆ wc_Tls13_HKDF_Extract()

int wc_Tls13_HKDF_Extract	(	byte *	prk,
		const byte *	salt,
		word32	saltLen,
		byte *	ikm,
		word32	ikmLen,
		int	digest
	)

This function provides access to RFC 5869 HMAC-based Extract-and-Expand Key Derivation Function (HKDF) for TLS v1.3 key derivation.

Returns: 0 Returned upon successfully generating a key with the given inputs; BAD_FUNC_ARG Returned if an invalid hash type is given (see type param); MEMORY_E Returned if there is an error allocating memory; HMAC_MIN_KEYLEN_E May be returned when using a FIPS implementation and the key length specified is shorter than the minimum acceptable FIPS standard

Parameters

prk	Generated pseudorandom key
salt	salt.
saltLen	length of the salt
ikm	pointer to putput for keying material
ikmLen	length of the input keying material buffer
digest	hash type to use for the HKDF. Valid types are: WC_SHA256, WC_SHA384 or WC_SHA512

Example

byte secret[] = { // initialize with random key };
byte salt[] = { // initialize with optional salt };
byte masterSecret[MAX_DIGEST_SIZE];
 
int ret = wc_Tls13_HKDF_Extract(secret, salt, sizeof(salt), 0,
    masterSecret, sizeof(masterSecret), WC_SHA512);
if ( ret != 0 ) {
    // error generating derived key
}

See also: wc_HKDF; wc_HKDF_Extract; wc_HKDF_Extract_ex; wc_HKDF_Expand; wc_Tls13_HKDF_Extract_ex

◆ wc_Tls13_HKDF_Extract_ex()

int wc_Tls13_HKDF_Extract_ex	(	byte *	prk,
		const byte *	salt,
		word32	saltLen,
		byte *	ikm,
		word32	ikmLen,
		int	digest,
		void *	heap,
		int	devId
	)

This function provides access to RFC 5869 HMAC-based Extract-and-Expand Key Derivation Function (HKDF) for TLS v1.3 key derivation. This is the _ex version adding heap hint and device identifier.

Returns: 0 Returned upon successfully generating a key with the given inputs; BAD_FUNC_ARG Returned if an invalid hash type is given (see type param); MEMORY_E Returned if there is an error allocating memory; HMAC_MIN_KEYLEN_E May be returned when using a FIPS implementation and the key length specified is shorter than the minimum acceptable FIPS standard

Parameters

prk	Generated pseudorandom key
salt	Salt.
saltLen	Length of the salt
ikm	Pointer to output for keying material
ikmLen	Length of the input keying material buffer
digest	Hash type to use for the HKDF. Valid types are: WC_SHA256, WC_SHA384 or WC_SHA512
heap	Heap hint to use for memory. Can be NULL
devId	ID to use with crypto callbacks or async hardware. Set to INVALID_DEVID (-2) if not used

Example

byte secret[] = { // initialize with random key };
byte salt[] = { // initialize with optional salt };
byte masterSecret[MAX_DIGEST_SIZE];
 
int ret = wc_Tls13_HKDF_Extract_ex(secret, salt, sizeof(salt), 0,
    masterSecret, sizeof(masterSecret), WC_SHA512, NULL, INVALID_DEVID);
if ( ret != 0 ) {
    // error generating derived key
}

See also: wc_HKDF; wc_HKDF_Extract; wc_HKDF_Extract_ex; wc_HKDF_Expand; wc_Tls13_HKDF_Extract

◆ wolfSSL_GetHmacMaxSize()

int wolfSSL_GetHmacMaxSize ( void )

This function returns the largest HMAC digest size available based on the configured cipher suites.

Returns: Success Returns the largest HMAC digest size available based on the configured cipher suites

Parameters

none	No parameters.

Example

int maxDigestSz = wolfSSL_GetHmacMaxSize();

wolfSSL_GetHmacMaxSize

int wolfSSL_GetHmacMaxSize(void)

This function returns the largest HMAC digest size available based on the configured cipher suites.

See also: none

Functions

Detailed Description

Function Documentation

◆ wc_HKDF()

◆ wc_HKDF_Expand()

◆ wc_HKDF_Expand_ex()

◆ wc_HKDF_Extract()

◆ wc_HKDF_Extract_ex()

◆ wc_HmacFinal()

◆ wc_HmacSetKey()

◆ wc_HmacUpdate()

◆ wc_Tls13_HKDF_Expand_Label()

◆ wc_Tls13_HKDF_Expand_Label_Alloc()

◆ wc_Tls13_HKDF_Expand_Label_ex()

◆ wc_Tls13_HKDF_Extract()

◆ wc_Tls13_HKDF_Extract_ex()

◆ wolfSSL_GetHmacMaxSize()