Files
wolfssl/wolfcrypt/src/ext_kyber.c
2022-12-30 17:12:11 -07:00

688 lines
17 KiB
C

/* ext_kyber.c
*
* Copyright (C) 2006-2023 wolfSSL Inc.
*
* This file is part of wolfSSL.
*
* wolfSSL 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.
*
* wolfSSL 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 02110-1335, USA
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <wolfssl/wolfcrypt/settings.h>
#include <wolfssl/wolfcrypt/error-crypt.h>
#ifdef WOLFSSL_HAVE_KYBER
#include <wolfssl/wolfcrypt/ext_kyber.h>
#ifdef NO_INLINE
#include <wolfssl/wolfcrypt/misc.h>
#else
#define WOLFSSL_MISC_INCLUDED
#include <wolfcrypt/src/misc.c>
#endif
#if defined (HAVE_LIBOQS)
static const char* OQS_ID2name(int id) {
switch (id) {
case KYBER_LEVEL1: return OQS_KEM_alg_kyber_512;
case KYBER_LEVEL3: return OQS_KEM_alg_kyber_768;
case KYBER_LEVEL5: return OQS_KEM_alg_kyber_1024;
default: break;
}
return NULL;
}
int ext_kyber_enabled(int id)
{
const char * name = OQS_ID2name(id);
return OQS_KEM_alg_is_enabled(name);
}
#endif
/******************************************************************************/
/* Initializer and cleanup functions. */
/**
* Initialize the Kyber key.
*
* @param [in] type Type of key: KYBER512, KYBER768, KYBER1024.
* @param [out] key Kyber key object to initialize.
* @param [in] heap Dynamic memory hint.
* @param [in] devId Device Id.
* @return 0 on success.
* @return BAD_FUNC_ARG when key is NULL or type is unrecognized.
* @return NOT_COMPILED_IN when key type is not supported.
*/
int wc_KyberKey_Init(int type, KyberKey* key, void* heap, int devId)
{
int ret = 0;
/* Validate key. */
if (key == NULL) {
ret = BAD_FUNC_ARG;
}
if (ret == 0) {
/* Validate type. */
switch (type) {
case KYBER_LEVEL1:
#ifdef HAVE_LIBOQS
case KYBER_LEVEL3:
case KYBER_LEVEL5:
#endif /* HAVE_LIBOQS */
break;
default:
/* No other values supported. */
ret = BAD_FUNC_ARG;
break;
}
}
if (ret == 0) {
/* Zero out all data. */
XMEMSET(key, 0, sizeof(*key));
/* Keep type for parameters. */
key->type = type;
}
(void)devId;
(void)heap;
return ret;
}
/**
* Free the Kyber key object.
*
* @param [in, out] key Kyber key object to dispose of.
*/
void wc_KyberKey_Free(KyberKey* key)
{
if (key != NULL) {
/* Ensure all private data is zeroed. */
ForceZero(key, sizeof(*key));
}
}
/******************************************************************************/
/* Data size getters. */
/**
* Get the size in bytes of encoded private key for the key.
*
* @param [in] key Kyber key object.
* @param [out] len Length of encoded private key in bytes.
* @return 0 on success.
* @return BAD_FUNC_ARG when key or len is NULL.
* @return NOT_COMPILED_IN when key type is not supported.
*/
int wc_KyberKey_PrivateKeySize(KyberKey* key, word32* len)
{
int ret = 0;
/* Validate parameters. */
if ((key == NULL) || (len == NULL)) {
ret = BAD_FUNC_ARG;
}
#ifdef HAVE_LIBOQS
/* NOTE: SHAKE and AES variants have the same length private key. */
if (ret == 0) {
switch (key->type) {
case KYBER_LEVEL1:
*len = OQS_KEM_kyber_512_length_secret_key;
break;
case KYBER_LEVEL3:
*len = OQS_KEM_kyber_768_length_secret_key;
break;
case KYBER_LEVEL5:
*len = OQS_KEM_kyber_1024_length_secret_key;
break;
default:
/* No other values supported. */
ret = BAD_FUNC_ARG;
break;
}
}
#endif /* HAVE_LIBOQS */
#ifdef HAVE_PQM4
(void)key;
if (ret == 0) {
*len = PQM4_PRIVATE_KEY_LENGTH;
}
#endif /* HAVE_PQM4 */
return ret;
}
/**
* Get the size in bytes of encoded public key for the key.
*
* @param [in] key Kyber key object.
* @param [out] len Length of encoded public key in bytes.
* @return 0 on success.
* @return BAD_FUNC_ARG when key or len is NULL.
* @return NOT_COMPILED_IN when key type is not supported.
*/
int wc_KyberKey_PublicKeySize(KyberKey* key, word32* len)
{
int ret = 0;
/* Validate parameters. */
if ((key == NULL) || (len == NULL)) {
ret = BAD_FUNC_ARG;
}
#ifdef HAVE_LIBOQS
/* NOTE: SHAKE and AES variants have the same length public key. */
if (ret == 0) {
switch (key->type) {
case KYBER_LEVEL1:
*len = OQS_KEM_kyber_512_length_public_key;
break;
case KYBER_LEVEL3:
*len = OQS_KEM_kyber_768_length_public_key;
break;
case KYBER_LEVEL5:
*len = OQS_KEM_kyber_1024_length_public_key;
break;
default:
/* No other values supported. */
ret = BAD_FUNC_ARG;
break;
}
}
#endif /* HAVE_LIBOQS */
#ifdef HAVE_PQM4
(void)key;
if (ret == 0) {
*len = PQM4_PUBLIC_KEY_LENGTH;
}
#endif /* HAVE_PQM4 */
return ret;
}
/**
* Get the size in bytes of cipher text for key.
*
* @param [in] key Kyber key object.
* @param [out] len Length of cipher text in bytes.
* @return 0 on success.
* @return BAD_FUNC_ARG when key or len is NULL.
* @return NOT_COMPILED_IN when key type is not supported.
*/
int wc_KyberKey_CipherTextSize(KyberKey* key, word32* len)
{
int ret = 0;
/* Validate parameters. */
if ((key == NULL) || (len == NULL)) {
ret = BAD_FUNC_ARG;
}
#ifdef HAVE_LIBOQS
/* NOTE: SHAKE and AES variants have the same length ciphertext. */
if (ret == 0) {
switch (key->type) {
case KYBER_LEVEL1:
*len = OQS_KEM_kyber_512_length_ciphertext;
break;
case KYBER_LEVEL3:
*len = OQS_KEM_kyber_768_length_ciphertext;
break;
case KYBER_LEVEL5:
*len = OQS_KEM_kyber_1024_length_ciphertext;
break;
default:
/* No other values supported. */
ret = BAD_FUNC_ARG;
break;
}
}
#endif /* HAVE_LIBOQS */
#ifdef HAVE_PQM4
(void)key;
if (ret == 0) {
*len = PQM4_CIPHERTEXT_LENGTH;
}
#endif /* HAVE_PQM4 */
return ret;
}
/**
* Size of a shared secret in bytes. Always KYBER_SS_SZ.
*
* @param [in] key Kyber key object. Not used.
* @param [out] Size of the shared secret created with a Kyber key.
* @return 0 on success.
* @return 0 to indicate success.
*/
int wc_KyberKey_SharedSecretSize(KyberKey* key, word32* len)
{
(void)key;
/* Validate parameters. */
if (len == NULL) {
return BAD_FUNC_ARG;
}
*len = KYBER_SS_SZ;
return 0;
}
/******************************************************************************/
/* Cryptographic operations. */
/**
* Make a Kyber key object using a random number generator.
*
* NOTE: rng is ignored. OQS and PQM4 don't use our RNG.
*
* @param [in, out] key Kyber key ovject.
* @param [in] rng Random number generator.
* @return 0 on success.
* @return BAD_FUNC_ARG when key or rng is NULL.
* @return MEMORY_E when dynamic memory allocation failed.
*/
int wc_KyberKey_MakeKey(KyberKey* key, WC_RNG* rng)
{
int ret = 0;
const char* algName = NULL;
OQS_KEM *kem = NULL;
(void)rng;
/* Validate parameter. */
if (key == NULL) {
return BAD_FUNC_ARG;
}
#ifdef HAVE_LIBOQS
if (ret == 0) {
algName = OQS_ID2name(key->type);
if (algName == NULL) {
ret = BAD_FUNC_ARG;
}
}
if (ret == 0) {
algName = OQS_ID2name(key->type);
if (algName == NULL) {
ret = BAD_FUNC_ARG;
}
}
if (ret == 0) {
kem = OQS_KEM_new(algName);
if (kem == NULL) {
ret = BAD_FUNC_ARG;
}
}
if (ret == 0) {
if (OQS_KEM_keypair(kem, key->pub, key->priv) !=
OQS_SUCCESS) {
ret = BAD_FUNC_ARG;
}
}
#endif /* HAVE_LIBOQS */
#ifdef HAVE_PQM4
if (ret == 0) {
if (crypto_kem_keypair(key->pub, key->priv) != 0) {
WOLFSSL_MSG("PQM4 keygen failure");
ret = BAD_FUNC_ARG;
}
}
#endif /* HAVE_PQM4 */
if (ret != 0) {
ForceZero(key, sizeof(*key));
}
OQS_KEM_free(kem);
return ret;
}
/**
* Make a Kyber key object using random data.
*
* @param [in, out] key Kyber key ovject.
* @param [in] rng Random number generator.
* @return 0 on success.
* @return BAD_FUNC_ARG when key or rand is NULL.
* @return BUFFER_E when length is not KYBER_MAKEKEY_RAND_SZ.
* @return NOT_COMPILED_IN when key type is not supported.
* @return MEMORY_E when dynamic memory allocation failed.
*/
int wc_KyberKey_MakeKeyWithRandom(KyberKey* key, const unsigned char* rand,
int len)
{
(void)rand;
(void)len;
/* OQS and PQM4 don't support external randomness. */
return wc_KyberKey_MakeKey(key, NULL);
}
/**
* Encapsulate with random number generator and derive secret.
*
* @param [in] key Kyber key object.
* @param [out] ct Cipher text.
* @param [out] ss Shared secret generated.
* @param [in] rng Random number generator.
* @return 0 on success.
* @return BAD_FUNC_ARG when key, ct, ss or RNG is NULL.
* @return NOT_COMPILED_IN when key type is not supported.
* @return MEMORY_E when dynamic memory allocation failed.
*/
int wc_KyberKey_Encapsulate(KyberKey* key, unsigned char* ct, unsigned char* ss,
WC_RNG* rng)
{
int ret = 0;
const char * algName = NULL;
OQS_KEM *kem = NULL;
(void)rng;
/* Validate parameters. */
if ((key == NULL) || (ct == NULL) || (ss == NULL)) {
ret = BAD_FUNC_ARG;
}
#ifdef HAVE_LIBOQS
if (ret == 0) {
algName = OQS_ID2name(key->type);
if (algName == NULL) {
ret = BAD_FUNC_ARG;
}
}
if (ret == 0) {
kem = OQS_KEM_new(algName);
if (kem == NULL) {
ret = BAD_FUNC_ARG;
}
}
if (ret == 0) {
if (OQS_KEM_encaps(kem, ct, ss, key->pub) != OQS_SUCCESS) {
ret = BAD_FUNC_ARG;
}
}
#endif /* HAVE_LIBOQS */
#ifdef HAVE_PQM4
if (ret == 0) {
if (crypto_kem_enc(ct, ss, key->pub) != 0) {
WOLFSSL_MSG("PQM4 Encapsulation failure.");
ret = BAD_FUNC_ARG;
}
}
#endif /* HAVE_PQM4 */
OQS_KEM_free(kem);
return ret;
}
/**
* Encapsulate with random data and derive secret.
*
* @param [out] ct Cipher text.
* @param [out] ss Shared secret generated.
* @param [in] rand Random data.
* @param [in] len Random data.
* @return 0 on success.
* @return BAD_FUNC_ARG when key, ct, ss or RNG is NULL.
* @return BUFFER_E when len is not KYBER_ENC_RAND_SZ.
* @return NOT_COMPILED_IN when key type is not supported.
* @return MEMORY_E when dynamic memory allocation failed.
*/
int wc_KyberKey_EncapsulateWithRandom(KyberKey* key, unsigned char* ct,
unsigned char* ss, const unsigned char* rand, int len)
{
(void)rand;
(void)len;
/* OQS and PQM4 don't support external randomness. */
return wc_KyberKey_Encapsulate(key, ct, ss, NULL);
}
/**
* Decapsulate the cipher text to calculate the shared secret.
*
* Validates the cipher text by encapsulating and comparing with data passed in.
*
* @param [in] key Kyber key object.
* @param [out] ss Shared secret.
* @param [in] ct Cipher text.
* @param [in] len Length of cipher text.
* @return 0 on success.
* @return BAD_FUNC_ARG when key, ss or cr are NULL.
* @return NOT_COMPILED_IN when key type is not supported.
* @return BUFFER_E when len is not the length of cipher text for the key type.
* @return MEMORY_E when dynamic memory allocation failed.
*/
int wc_KyberKey_Decapsulate(KyberKey* key, unsigned char* ss,
const unsigned char* ct, word32 len)
{
int ret = 0;
const char * algName = NULL;
word32 ctlen = 0;
OQS_KEM *kem = NULL;
/* Validate parameters. */
if ((key == NULL) || (ss == NULL) || (ct == NULL)) {
ret = BAD_FUNC_ARG;
}
if (ret == 0) {
ret = wc_KyberKey_CipherTextSize(key, &ctlen);
}
if ((ret == 0) && (len != ctlen)) {
ret = BUFFER_E;
}
#ifdef HAVE_LIBOQS
if (ret == 0) {
algName = OQS_ID2name(key->type);
if (algName == NULL) {
ret = BAD_FUNC_ARG;
}
}
if (ret == 0) {
kem = OQS_KEM_new(algName);
if (kem == NULL) {
ret = BAD_FUNC_ARG;
}
}
if (ret == 0) {
if (OQS_KEM_decaps(kem, ss, ct, key->priv) != OQS_SUCCESS) {
ret = BAD_FUNC_ARG;
}
}
#endif /* HAVE_LIBOQS */
#ifdef HAVE_PQM4
if (ret == 0) {
if (crypto_kem_enc(ss, ct, key->priv) != 0) {
WOLFSSL_MSG("PQM4 Decapsulation failure.");
ret = BAD_FUNC_ARG;
}
}
#endif /* HAVE_PQM4 */
OQS_KEM_free(kem);
return ret;
}
/******************************************************************************/
/* Encoding and decoding functions. */
/**
* Decode the private key.
*
* We store the whole thing in the private key buffer. Note this means we cannot
* do the encapsulation operation with the private key. But generally speaking
* this is never done.
*
* @param [in, out] key Kyber key object.
* @param [in] in Buffer holding encoded key.
* @param [in] len Length of data in buffer.
* @return 0 on success.
* @return BAD_FUNC_ARG when key ot in is NULL.
* @return NOT_COMPILED_IN when key type is not supported.
* @return BUFFER_E when len is not the correct size.
*/
int wc_KyberKey_DecodePrivateKey(KyberKey* key, unsigned char* in, word32 len)
{
int ret = 0;
word32 privLen = 0;
/* Validate parameters. */
if ((key == NULL) || (in == NULL)) {
ret = BAD_FUNC_ARG;
}
if (ret == 0) {
ret = wc_KyberKey_PrivateKeySize(key, &privLen);
}
/* Ensure the data is the correct length for the key type. */
if ((ret == 0) && (len != privLen)) {
ret = BUFFER_E;
}
if (ret == 0) {
XMEMCPY(key->priv, in, privLen);
}
return ret;
}
/**
* Decode public key.
*
* We store the whole thing in the public key buffer.
*
* @param [in, out] key Kyber key object.
* @param [in] in Buffer holding encoded key.
* @param [in] len Length of data in buffer.
* @return 0 on success.
* @return BAD_FUNC_ARG when key or in is NULL.
* @return NOT_COMPILED_IN when key type is not supported.
* @return BUFFER_E when len is not the correct size.
*/
int wc_KyberKey_DecodePublicKey(KyberKey* key, unsigned char* in, word32 len)
{
int ret = 0;
word32 pubLen = 0;
/* Validate parameters. */
if ((key == NULL) || (in == NULL)) {
ret = BAD_FUNC_ARG;
}
if (ret == 0) {
ret = wc_KyberKey_PublicKeySize(key, &pubLen);
}
/* Ensure the data is the correct length for the key type. */
if ((ret == 0) && (len != pubLen)) {
ret = BUFFER_E;
}
if (ret == 0) {
XMEMCPY(key->pub, in, pubLen);
}
return ret;
}
/**
* Encode the private key.
*
* We stored it as a blob so we can just copy it over.
*
* @param [in] key Kyber key object.
* @param [out] out Buffer to hold data.
* @param [in] len Size of buffer in bytes.
* @return 0 on success.
* @return BAD_FUNC_ARG when key or out is NULL or private/public key not
* available.
* @return NOT_COMPILED_IN when key type is not supported.
*/
int wc_KyberKey_EncodePrivateKey(KyberKey* key, unsigned char* out, word32 len)
{
int ret = 0;
unsigned int privLen = 0;
if ((key == NULL) || (out == NULL)) {
ret = BAD_FUNC_ARG;
}
if (ret == 0) {
ret = wc_KyberKey_PrivateKeySize(key, &privLen);
}
/* Check buffer is big enough for encoding. */
if ((ret == 0) && (len != privLen)) {
ret = BUFFER_E;
}
if (ret == 0) {
XMEMCPY(out, key->priv, privLen);
}
return ret;
}
/**
* Encode the public key.
*
* We stored it as a blob so we can just copy it over.
*
* @param [in] key Kyber key object.
* @param [out] out Buffer to hold data.
* @param [in] len Size of buffer in bytes.
* @return 0 on success.
* @return BAD_FUNC_ARG when key or out is NULL or public key not available.
* @return NOT_COMPILED_IN when key type is not supported.
*/
int wc_KyberKey_EncodePublicKey(KyberKey* key, unsigned char* out, word32 len)
{
int ret = 0;
unsigned int pubLen = 0;
if ((key == NULL) || (out == NULL)) {
ret = BAD_FUNC_ARG;
}
if (ret == 0) {
ret = wc_KyberKey_PublicKeySize(key, &pubLen);
}
/* Check buffer is big enough for encoding. */
if ((ret == 0) && (len != pubLen)) {
ret = BUFFER_E;
}
if (ret == 0) {
XMEMCPY(out, key->pub, pubLen);
}
return ret;
}
#endif /* WOLFSSL_HAVE_KYBER */