rsa.c File Reference

RSA public-key cryptography standard. More...

#include "core/crypto.h"
#include "pkc/rsa.h"
#include "pkc/rsa_misc.h"
#include "debug.h"

Go to the source code of this file.

Macros
#define	TRACE_LEVEL   CRYPTO_TRACE_LEVEL

Functions
void	rsaInitPublicKey (RsaPublicKey *key)
	Initialize an RSA public key. More...
void	rsaFreePublicKey (RsaPublicKey *key)
	Release an RSA public key. More...
void	rsaInitPrivateKey (RsaPrivateKey *key)
	Initialize an RSA private key. More...
void	rsaFreePrivateKey (RsaPrivateKey *key)
	Release an RSA private key. More...
error_t	rsaGenerateKeyPair (const PrngAlgo *prngAlgo, void *prngContext, size_t k, uint_t e, RsaPrivateKey *privateKey, RsaPublicKey *publicKey)
	RSA key pair generation. More...
__weak_func error_t	rsaGeneratePrivateKey (const PrngAlgo *prngAlgo, void *prngContext, size_t k, uint_t e, RsaPrivateKey *privateKey)
	RSA private key generation. More...
error_t	rsaGeneratePublicKey (const RsaPrivateKey *privateKey, RsaPublicKey *publicKey)
	Derive the public key from an RSA private key. More...
error_t	rsaesPkcs1v15Encrypt (const PrngAlgo *prngAlgo, void *prngContext, const RsaPublicKey *key, const uint8_t *message, size_t messageLen, uint8_t *ciphertext, size_t *ciphertextLen)
	RSAES-PKCS1-v1_5 encryption operation. More...
error_t	rsaesPkcs1v15Decrypt (const RsaPrivateKey *key, const uint8_t *ciphertext, size_t ciphertextLen, uint8_t *message, size_t messageSize, size_t *messageLen)
	RSAES-PKCS1-v1_5 decryption operation. More...
error_t	rsaesOaepEncrypt (const PrngAlgo *prngAlgo, void *prngContext, const RsaPublicKey *key, const HashAlgo *hash, const char_t *label, const uint8_t *message, size_t messageLen, uint8_t *ciphertext, size_t *ciphertextLen)
	RSAES-OAEP encryption operation. More...
error_t	rsaesOaepDecrypt (const RsaPrivateKey *key, const HashAlgo *hash, const char_t *label, const uint8_t *ciphertext, size_t ciphertextLen, uint8_t *message, size_t messageSize, size_t *messageLen)
	RSAES-OAEP decryption operation. More...
error_t	rsassaPkcs1v15Sign (const RsaPrivateKey *key, const HashAlgo *hash, const uint8_t *digest, uint8_t *signature, size_t *signatureLen)
	RSASSA-PKCS1-v1_5 signature generation operation. More...
error_t	rsassaPkcs1v15Verify (const RsaPublicKey *key, const HashAlgo *hash, const uint8_t *digest, const uint8_t *signature, size_t signatureLen)
	RSASSA-PKCS1-v1_5 signature verification operation. More...
error_t	rsassaPssSign (const PrngAlgo *prngAlgo, void *prngContext, const RsaPrivateKey *key, const HashAlgo *hash, size_t saltLen, const uint8_t *digest, uint8_t *signature, size_t *signatureLen)
	RSASSA-PSS signature generation operation. More...
error_t	rsassaPssVerify (const RsaPublicKey *key, const HashAlgo *hash, size_t saltLen, const uint8_t *digest, const uint8_t *signature, size_t signatureLen)
	RSASSA-PSS signature verification operation. More...

Variables
const uint8_t	PKCS1_OID [8] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01}
const uint8_t	RSA_ENCRYPTION_OID [9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x01}
const uint8_t	MD2_WITH_RSA_ENCRYPTION_OID [9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x02}
const uint8_t	MD5_WITH_RSA_ENCRYPTION_OID [9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x04}
const uint8_t	SHA1_WITH_RSA_ENCRYPTION_OID [9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x05}
const uint8_t	SHA224_WITH_RSA_ENCRYPTION_OID [9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0E}
const uint8_t	SHA256_WITH_RSA_ENCRYPTION_OID [9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0B}
const uint8_t	SHA384_WITH_RSA_ENCRYPTION_OID [9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0C}
const uint8_t	SHA512_WITH_RSA_ENCRYPTION_OID [9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0D}
const uint8_t	SHA512_224_WITH_RSA_ENCRYPTION_OID [9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0F}
const uint8_t	SHA512_256_WITH_RSA_ENCRYPTION_OID [9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x10}
const uint8_t	RSASSA_PKCS1_V1_5_WITH_SHA3_224_OID [9] = {0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x03, 0x0D}
const uint8_t	RSASSA_PKCS1_V1_5_WITH_SHA3_256_OID [9] = {0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x03, 0x0E}
const uint8_t	RSASSA_PKCS1_V1_5_WITH_SHA3_384_OID [9] = {0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x03, 0x0F}
const uint8_t	RSASSA_PKCS1_V1_5_WITH_SHA3_512_OID [9] = {0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x03, 0x10}
const uint8_t	RSASSA_PSS_OID [9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0A}
const uint8_t	RSASSA_PSS_SHAKE128_OID [8] = {0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x06, 0x1E}
const uint8_t	RSASSA_PSS_SHAKE256_OID [8] = {0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x06, 0x1F}
const uint8_t	MGF1_OID [9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x08}

Detailed Description

RSA public-key cryptography standard.

License

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

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

This file is part of CycloneCRYPTO 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.

Description

RSA is an algorithm for public-key cryptography which is suitable for signing as well as encryption. Refer to the following RFCs for complete details:

• RFC 2313: PKCS #1: RSA Encryption Version 1.5
• RFC 3447: PKCS #1: RSA Cryptography Specifications Version 2.1
• RFC 8017: PKCS #1: RSA Cryptography Specifications Version 2.2

Author

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

Version

2.5.0

Definition in file rsa.c.

Macro Definition Documentation

TRACE_LEVEL

#define TRACE_LEVEL   CRYPTO_TRACE_LEVEL

Definition at line 40 of file rsa.c.

Function Documentation

rsaesOaepDecrypt()

error_t rsaesOaepDecrypt	(	const RsaPrivateKey *	key,
		const HashAlgo *	hash,
		const char_t *	label,
		const uint8_t *	ciphertext,
		size_t	ciphertextLen,
		uint8_t *	message,
		size_t	messageSize,
		size_t *	messageLen
	)

RSAES-OAEP decryption operation.

Parameters

[in]	key	Recipient's RSA private key
[in]	hash	Underlying hash function
[in]	label	Optional label to be associated with the message
[in]	ciphertext	Ciphertext to be decrypted
[in]	ciphertextLen	Length of the ciphertext to be decrypted
[out]	message	Output buffer where to store the decrypted message
[in]	messageSize	Size of the output buffer
[out]	messageLen	Length of the decrypted message

Returns

Error code

Definition at line 774 of file rsa.c.

rsaesOaepEncrypt()

error_t rsaesOaepEncrypt	(	const PrngAlgo *	prngAlgo,
		void *	prngContext,
		const RsaPublicKey *	key,
		const HashAlgo *	hash,
		const char_t *	label,
		const uint8_t *	message,
		size_t	messageLen,
		uint8_t *	ciphertext,
		size_t *	ciphertextLen
	)

RSAES-OAEP encryption operation.

Parameters

[in]	prngAlgo	PRNG algorithm
[in]	prngContext	Pointer to the PRNG context
[in]	key	Recipient's RSA public key
[in]	hash	Underlying hash function
[in]	label	Optional label to be associated with the message
[in]	message	Message to be encrypted
[in]	messageLen	Length of the message to be encrypted
[out]	ciphertext	Ciphertext resulting from the encryption operation
[out]	ciphertextLen	Length of the resulting ciphertext

Returns

Error code

Definition at line 668 of file rsa.c.

rsaesPkcs1v15Decrypt()

error_t rsaesPkcs1v15Decrypt	(	const RsaPrivateKey *	key,
		const uint8_t *	ciphertext,
		size_t	ciphertextLen,
		uint8_t *	message,
		size_t	messageSize,
		size_t *	messageLen
	)

RSAES-PKCS1-v1_5 decryption operation.

Parameters

[in]	key	Recipient's RSA private key
[in]	ciphertext	Ciphertext to be decrypted
[in]	ciphertextLen	Length of the ciphertext to be decrypted
[out]	message	Output buffer where to store the decrypted message
[in]	messageSize	Size of the output buffer
[out]	messageLen	Length of the decrypted message

Returns

Error code

Definition at line 507 of file rsa.c.

rsaesPkcs1v15Encrypt()

error_t rsaesPkcs1v15Encrypt	(	const PrngAlgo *	prngAlgo,
		void *	prngContext,
		const RsaPublicKey *	key,
		const uint8_t *	message,
		size_t	messageLen,
		uint8_t *	ciphertext,
		size_t *	ciphertextLen
	)

RSAES-PKCS1-v1_5 encryption operation.

Parameters

[in]	prngAlgo	PRNG algorithm
[in]	prngContext	Pointer to the PRNG context
[in]	key	Recipient's RSA public key
[in]	message	Message to be encrypted
[in]	messageLen	Length of the message to be encrypted
[out]	ciphertext	Ciphertext resulting from the encryption operation
[out]	ciphertextLen	Length of the resulting ciphertext

Returns

Error code

Definition at line 409 of file rsa.c.

rsaFreePrivateKey()

void rsaFreePrivateKey

(

RsaPrivateKey *

key

)

Release an RSA private key.

Parameters

[in]

key

Pointer to the RSA private key to free

Definition at line 148 of file rsa.c.

rsaFreePublicKey()

void rsaFreePublicKey

(

RsaPublicKey *

key

)

Release an RSA public key.

Parameters

[in]

key

Pointer to the RSA public key to free

Definition at line 113 of file rsa.c.

rsaGenerateKeyPair()

error_t rsaGenerateKeyPair	(	const PrngAlgo *	prngAlgo,
		void *	prngContext,
		size_t	k,
		uint_t	e,
		RsaPrivateKey *	privateKey,
		RsaPublicKey *	publicKey
	)

RSA key pair generation.

Parameters

[in]	prngAlgo	PRNG algorithm
[in]	prngContext	Pointer to the PRNG context
[in]	k	Required bit length of the modulus n
[in]	e	Public exponent (3, 5, 17, 257 or 65537)
[out]	privateKey	RSA private key
[out]	publicKey	RSA public key

Returns

Error code

Definition at line 173 of file rsa.c.

rsaGeneratePrivateKey()

__weak_func error_t rsaGeneratePrivateKey	(	const PrngAlgo *	prngAlgo,
		void *	prngContext,
		size_t	k,
		uint_t	e,
		RsaPrivateKey *	privateKey
	)

RSA private key generation.

Parameters

[in]	prngAlgo	PRNG algorithm
[in]	prngContext	Pointer to the PRNG context
[in]	k	Required bit length of the modulus n
[in]	e	Public exponent (3, 5, 17, 257 or 65537)
[out]	privateKey	RSA private key

Returns

Error code

Definition at line 203 of file rsa.c.

rsaGeneratePublicKey()

error_t rsaGeneratePublicKey	(	const RsaPrivateKey *	privateKey,
		RsaPublicKey *	publicKey
	)

Derive the public key from an RSA private key.

Parameters

[in]	privateKey	RSA private key
[out]	publicKey	RSA public key

Returns

Error code

Definition at line 364 of file rsa.c.

rsaInitPrivateKey()

void rsaInitPrivateKey

(

RsaPrivateKey *

key

)

Initialize an RSA private key.

Parameters

[in]

key

Pointer to the RSA private key to initialize

Definition at line 126 of file rsa.c.

rsaInitPublicKey()

void rsaInitPublicKey

(

RsaPublicKey *

key

)

Initialize an RSA public key.

Parameters

[in]

key

Pointer to the RSA public key to initialize

Definition at line 100 of file rsa.c.

rsassaPkcs1v15Sign()

error_t rsassaPkcs1v15Sign	(	const RsaPrivateKey *	key,
		const HashAlgo *	hash,
		const uint8_t *	digest,
		uint8_t *	signature,
		size_t *	signatureLen
	)

RSASSA-PKCS1-v1_5 signature generation operation.

Parameters

[in]	key	Signer's RSA private key
[in]	hash	Hash function used to digest the message
[in]	digest	Digest of the message to be signed
[out]	signature	Resulting signature
[out]	signatureLen	Length of the resulting signature

Returns

Error code

Definition at line 935 of file rsa.c.

rsassaPkcs1v15Verify()

error_t rsassaPkcs1v15Verify	(	const RsaPublicKey *	key,
		const HashAlgo *	hash,
		const uint8_t *	digest,
		const uint8_t *	signature,
		size_t	signatureLen
	)

RSASSA-PKCS1-v1_5 signature verification operation.

Parameters

[in]	key	Signer's RSA public key
[in]	hash	Hash function used to digest the message
[in]	digest	Digest of the message whose signature is to be verified
[in]	signature	Signature to be verified
[in]	signatureLen	Length of the signature to be verified

Returns

Error code

Definition at line 1068 of file rsa.c.

rsassaPssSign()

error_t rsassaPssSign	(	const PrngAlgo *	prngAlgo,
		void *	prngContext,
		const RsaPrivateKey *	key,
		const HashAlgo *	hash,
		size_t	saltLen,
		const uint8_t *	digest,
		uint8_t *	signature,
		size_t *	signatureLen
	)

RSASSA-PSS signature generation operation.

Parameters

[in]	prngAlgo	PRNG algorithm
[in]	prngContext	Pointer to the PRNG context
[in]	key	Signer's RSA private key
[in]	hash	Hash function used to digest the message
[in]	saltLen	Length of the salt, in bytes
[in]	digest	Digest of the message to be signed
[out]	signature	Resulting signature
[out]	signatureLen	Length of the resulting signature

Returns

Error code

Definition at line 1189 of file rsa.c.

rsassaPssVerify()

error_t rsassaPssVerify	(	const RsaPublicKey *	key,
		const HashAlgo *	hash,
		size_t	saltLen,
		const uint8_t *	digest,
		const uint8_t *	signature,
		size_t	signatureLen
	)

RSASSA-PSS signature verification operation.

Parameters

[in]	key	Signer's RSA public key
[in]	hash	Hash function used to digest the message
[in]	saltLen	Length of the salt, in bytes
[in]	digest	Digest of the message whose signature is to be verified
[in]	signature	Signature to be verified
[in]	signatureLen	Length of the signature to be verified

Returns

Error code

Definition at line 1309 of file rsa.c.

Variable Documentation

MD2_WITH_RSA_ENCRYPTION_OID

const uint8_t MD2_WITH_RSA_ENCRYPTION_OID[9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x02}

Definition at line 57 of file rsa.c.

MD5_WITH_RSA_ENCRYPTION_OID

const uint8_t MD5_WITH_RSA_ENCRYPTION_OID[9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x04}

Definition at line 59 of file rsa.c.

MGF1_OID

const uint8_t MGF1_OID[9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x08}

Definition at line 92 of file rsa.c.

PKCS1_OID

const uint8_t PKCS1_OID[8] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01}

Definition at line 52 of file rsa.c.

RSA_ENCRYPTION_OID

const uint8_t RSA_ENCRYPTION_OID[9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x01}

Definition at line 54 of file rsa.c.

RSASSA_PKCS1_V1_5_WITH_SHA3_224_OID

const uint8_t RSASSA_PKCS1_V1_5_WITH_SHA3_224_OID[9] = {0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x03, 0x0D}

Definition at line 76 of file rsa.c.

RSASSA_PKCS1_V1_5_WITH_SHA3_256_OID

const uint8_t RSASSA_PKCS1_V1_5_WITH_SHA3_256_OID[9] = {0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x03, 0x0E}

Definition at line 78 of file rsa.c.

RSASSA_PKCS1_V1_5_WITH_SHA3_384_OID

const uint8_t RSASSA_PKCS1_V1_5_WITH_SHA3_384_OID[9] = {0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x03, 0x0F}

Definition at line 80 of file rsa.c.

RSASSA_PKCS1_V1_5_WITH_SHA3_512_OID

const uint8_t RSASSA_PKCS1_V1_5_WITH_SHA3_512_OID[9] = {0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x03, 0x10}

Definition at line 82 of file rsa.c.

RSASSA_PSS_OID

const uint8_t RSASSA_PSS_OID[9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0A}

Definition at line 85 of file rsa.c.

RSASSA_PSS_SHAKE128_OID

const uint8_t RSASSA_PSS_SHAKE128_OID[8] = {0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x06, 0x1E}

Definition at line 87 of file rsa.c.

RSASSA_PSS_SHAKE256_OID

const uint8_t RSASSA_PSS_SHAKE256_OID[8] = {0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x06, 0x1F}

Definition at line 89 of file rsa.c.

SHA1_WITH_RSA_ENCRYPTION_OID

const uint8_t SHA1_WITH_RSA_ENCRYPTION_OID[9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x05}

Definition at line 61 of file rsa.c.

SHA224_WITH_RSA_ENCRYPTION_OID

const uint8_t SHA224_WITH_RSA_ENCRYPTION_OID[9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0E}

Definition at line 63 of file rsa.c.

SHA256_WITH_RSA_ENCRYPTION_OID

const uint8_t SHA256_WITH_RSA_ENCRYPTION_OID[9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0B}

Definition at line 65 of file rsa.c.

SHA384_WITH_RSA_ENCRYPTION_OID

const uint8_t SHA384_WITH_RSA_ENCRYPTION_OID[9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0C}

Definition at line 67 of file rsa.c.

SHA512_224_WITH_RSA_ENCRYPTION_OID

const uint8_t SHA512_224_WITH_RSA_ENCRYPTION_OID[9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0F}

Definition at line 71 of file rsa.c.

SHA512_256_WITH_RSA_ENCRYPTION_OID

const uint8_t SHA512_256_WITH_RSA_ENCRYPTION_OID[9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x10}

Definition at line 73 of file rsa.c.

SHA512_WITH_RSA_ENCRYPTION_OID

const uint8_t SHA512_WITH_RSA_ENCRYPTION_OID[9] = {0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0D}

Definition at line 69 of file rsa.c.