tls_key_material.c File Reference

Key material generation. More...

#include "tls.h"
#include "tls_key_material.h"
#include "tls_transcript_hash.h"
#include "debug.h"

Go to the source code of this file.

Macros
#define	TRACE_LEVEL   TLS_TRACE_LEVEL

Functions
error_t	tlsGenerateSessionKeys (TlsContext *context)
	Generate session keys. More...
__weak_func error_t	tlsGenerateMasterSecret (TlsContext *context)
	Master secret computation. More...
error_t	tlsGenerateExtendedMasterSecret (TlsContext *context)
	Extended master secret computation. More...
error_t	tlsGeneratePskPremasterSecret (TlsContext *context)
	Premaster secret generation (for PSK cipher suites) More...
__weak_func error_t	tlsGenerateKeyBlock (TlsContext *context, size_t keyBlockLen)
	Key expansion function. More...
error_t	tlsPrf (const uint8_t *secret, size_t secretLen, const char_t *label, const uint8_t *seed, size_t seedLen, uint8_t *output, size_t outputLen)
	Pseudorandom function (TLS 1.0 and 1.1) More...
error_t	tls12Prf (const HashAlgo *hash, const uint8_t *secret, size_t secretLen, const char_t *label, const uint8_t *seed, size_t seedLen, uint8_t *output, size_t outputLen)
	Pseudorandom function (TLS 1.2) More...
void	tlsDumpSecret (TlsContext *context, const char_t *label, const uint8_t *secret, size_t secretLen)
	Dump secret key (for debugging purpose only) More...

Detailed Description

Key material generation.

License

SPDX-License-Identifier: GPL-2.0-or-later

Copyright (C) 2010-2025 Oryx Embedded SARL. All rights reserved.

This file is part of CycloneSSL Open.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

Author

Oryx Embedded SARL (www.oryx-embedded.com)

Version

2.5.0

Definition in file tls_key_material.c.

Macro Definition Documentation

TRACE_LEVEL

#define TRACE_LEVEL   TLS_TRACE_LEVEL

Definition at line 32 of file tls_key_material.c.

Function Documentation

tls12Prf()

error_t tls12Prf	(	const HashAlgo *	hash,
		const uint8_t *	secret,
		size_t	secretLen,
		const char_t *	label,
		const uint8_t *	seed,
		size_t	seedLen,
		uint8_t *	output,
		size_t	outputLen
	)

Pseudorandom function (TLS 1.2)

The pseudorandom function (PRF) takes as input a secret, a seed, and an identifying label and produces an output of arbitrary length. This function is used to expand secrets into blocks of data for the purpose of key generation

Parameters

[in]	hash	Hash function used to compute PRF
[in]	secret	Pointer to the secret
[in]	secretLen	Length of the secret
[in]	label	Identifying label (NULL-terminated string)
[in]	seed	Pointer to the seed
[in]	seedLen	Length of the seed
[out]	output	Pointer to the output
[in]	outputLen	Desired output length

Returns

Error code

Definition at line 580 of file tls_key_material.c.

tlsDumpSecret()

void tlsDumpSecret	(	TlsContext *	context,
		const char_t *	label,
		const uint8_t *	secret,
		size_t	secretLen
	)

Dump secret key (for debugging purpose only)

Parameters

[in]	context	Pointer to the TLS context
[in]	label	Identifying label (NULL-terminated string)
[in]	secret	Pointer to the secret key
[in]	secretLen	Length of the secret key, in bytes

Definition at line 661 of file tls_key_material.c.

tlsGenerateExtendedMasterSecret()

error_t tlsGenerateExtendedMasterSecret

(

TlsContext *

context

)

Extended master secret computation.

Parameters

[in]

context

Pointer to the TLS context

Returns

Error code

Definition at line 192 of file tls_key_material.c.

tlsGenerateKeyBlock()

__weak_func error_t tlsGenerateKeyBlock	(	TlsContext *	context,
		size_t	keyBlockLen
	)

Key expansion function.

Parameters

[in]	context	Pointer to the TLS context
[in]	keyBlockLen	Desired length for the resulting key block

Returns

Error code

Definition at line 392 of file tls_key_material.c.

tlsGenerateMasterSecret()

__weak_func error_t tlsGenerateMasterSecret

(

TlsContext *

context

)

Master secret computation.

Parameters

[in]

context

Pointer to the TLS context

Returns

Error code

Definition at line 142 of file tls_key_material.c.

tlsGeneratePskPremasterSecret()

error_t tlsGeneratePskPremasterSecret

(

TlsContext *

context

)

Premaster secret generation (for PSK cipher suites)

Parameters

[in]

context

Pointer to the TLS context

Returns

Error code

Definition at line 290 of file tls_key_material.c.

tlsGenerateSessionKeys()

error_t tlsGenerateSessionKeys

(

TlsContext *

context

)

Generate session keys.

Parameters

[in]

context

Pointer to the TLS context

Returns

Error code

Definition at line 50 of file tls_key_material.c.

tlsPrf()

error_t tlsPrf	(	const uint8_t *	secret,
		size_t	secretLen,
		const char_t *	label,
		const uint8_t *	seed,
		size_t	seedLen,
		uint8_t *	output,
		size_t	outputLen
	)

Pseudorandom function (TLS 1.0 and 1.1)

The pseudorandom function (PRF) takes as input a secret, a seed, and an identifying label and produces an output of arbitrary length. This function is used to expand secrets into blocks of data for the purpose of key generation

Parameters

[in]	secret	Pointer to the secret
[in]	secretLen	Length of the secret
[in]	label	Identifying label (NULL-terminated string)
[in]	seed	Pointer to the seed
[in]	seedLen	Length of the seed
[out]	output	Pointer to the output
[in]	outputLen	Desired output length

Returns

Error code

Definition at line 453 of file tls_key_material.c.