[mirror_qemu.git] / crypto / cipher-nettle.c

/*
 * QEMU Crypto cipher nettle algorithms
 *
 * Copyright (c) 2015 Red Hat, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 *
 */

#include <nettle/nettle-types.h>
#include <nettle/aes.h>
#include <nettle/des.h>
#include <nettle/cbc.h>

#if CONFIG_NETTLE_VERSION_MAJOR < 3
typedef nettle_crypt_func nettle_cipher_func;

typedef void *       cipher_ctx_t;
typedef unsigned     cipher_length_t;
#else
typedef const void * cipher_ctx_t;
typedef size_t       cipher_length_t;
#endif

static nettle_cipher_func aes_encrypt_wrapper;
static nettle_cipher_func aes_decrypt_wrapper;
static nettle_cipher_func des_encrypt_wrapper;
static nettle_cipher_func des_decrypt_wrapper;

static void aes_encrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
                                uint8_t *dst, const uint8_t *src)
{
    aes_encrypt(ctx, length, dst, src);
}

static void aes_decrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
                                uint8_t *dst, const uint8_t *src)
{
    aes_decrypt(ctx, length, dst, src);
}

static void des_encrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
                                uint8_t *dst, const uint8_t *src)
{
    des_encrypt(ctx, length, dst, src);
}

static void des_decrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
                                uint8_t *dst, const uint8_t *src)
{
    des_decrypt(ctx, length, dst, src);
}

typedef struct QCryptoCipherNettle QCryptoCipherNettle;
struct QCryptoCipherNettle {
    void *ctx_encrypt;
    void *ctx_decrypt;
    nettle_cipher_func *alg_encrypt;
    nettle_cipher_func *alg_decrypt;
    uint8_t *iv;
    size_t niv;
};

bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg)
{
    switch (alg) {
    case QCRYPTO_CIPHER_ALG_DES_RFB:
    case QCRYPTO_CIPHER_ALG_AES_128:
    case QCRYPTO_CIPHER_ALG_AES_192:
    case QCRYPTO_CIPHER_ALG_AES_256:
        return true;
    default:
        return false;
    }
}


QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
                                  QCryptoCipherMode mode,
                                  const uint8_t *key, size_t nkey,
                                  Error **errp)
{
    QCryptoCipher *cipher;
    QCryptoCipherNettle *ctx;
    uint8_t *rfbkey;

    switch (mode) {
    case QCRYPTO_CIPHER_MODE_ECB:
    case QCRYPTO_CIPHER_MODE_CBC:
        break;
    default:
        error_setg(errp, "Unsupported cipher mode %d", mode);
        return NULL;
    }

    if (!qcrypto_cipher_validate_key_length(alg, nkey, errp)) {
        return NULL;
    }

    cipher = g_new0(QCryptoCipher, 1);
    cipher->alg = alg;
    cipher->mode = mode;

    ctx = g_new0(QCryptoCipherNettle, 1);

    switch (alg) {
    case QCRYPTO_CIPHER_ALG_DES_RFB:
        ctx->ctx_encrypt = g_new0(struct des_ctx, 1);
        ctx->ctx_decrypt = NULL; /* 1 ctx can do both */
        rfbkey = qcrypto_cipher_munge_des_rfb_key(key, nkey);
        des_set_key(ctx->ctx_encrypt, rfbkey);
        g_free(rfbkey);

        ctx->alg_encrypt = des_encrypt_wrapper;
        ctx->alg_decrypt = des_decrypt_wrapper;

        ctx->niv = DES_BLOCK_SIZE;
        break;

    case QCRYPTO_CIPHER_ALG_AES_128:
    case QCRYPTO_CIPHER_ALG_AES_192:
    case QCRYPTO_CIPHER_ALG_AES_256:
        ctx->ctx_encrypt = g_new0(struct aes_ctx, 1);
        ctx->ctx_decrypt = g_new0(struct aes_ctx, 1);

        aes_set_encrypt_key(ctx->ctx_encrypt, nkey, key);
        aes_set_decrypt_key(ctx->ctx_decrypt, nkey, key);

        ctx->alg_encrypt = aes_encrypt_wrapper;
        ctx->alg_decrypt = aes_decrypt_wrapper;

        ctx->niv = AES_BLOCK_SIZE;
        break;
    default:
        error_setg(errp, "Unsupported cipher algorithm %d", alg);
        goto error;
    }

    ctx->iv = g_new0(uint8_t, ctx->niv);
    cipher->opaque = ctx;

    return cipher;

 error:
    g_free(cipher);
    g_free(ctx);
    return NULL;
}


void qcrypto_cipher_free(QCryptoCipher *cipher)
{
    QCryptoCipherNettle *ctx;

    if (!cipher) {
        return;
    }

    ctx = cipher->opaque;
    g_free(ctx->iv);
    g_free(ctx->ctx_encrypt);
    g_free(ctx->ctx_decrypt);
    g_free(ctx);
    g_free(cipher);
}


int qcrypto_cipher_encrypt(QCryptoCipher *cipher,
                           const void *in,
                           void *out,
                           size_t len,
                           Error **errp)
{
    QCryptoCipherNettle *ctx = cipher->opaque;

    switch (cipher->mode) {
    case QCRYPTO_CIPHER_MODE_ECB:
        ctx->alg_encrypt(ctx->ctx_encrypt, len, out, in);
        break;

    case QCRYPTO_CIPHER_MODE_CBC:
        cbc_encrypt(ctx->ctx_encrypt, ctx->alg_encrypt,
                    ctx->niv, ctx->iv,
                    len, out, in);
        break;
    default:
        error_setg(errp, "Unsupported cipher algorithm %d",
                   cipher->alg);
        return -1;
    }
    return 0;
}


int qcrypto_cipher_decrypt(QCryptoCipher *cipher,
                           const void *in,
                           void *out,
                           size_t len,
                           Error **errp)
{
    QCryptoCipherNettle *ctx = cipher->opaque;

    switch (cipher->mode) {
    case QCRYPTO_CIPHER_MODE_ECB:
        ctx->alg_decrypt(ctx->ctx_decrypt ? ctx->ctx_decrypt : ctx->ctx_encrypt,
                         len, out, in);
        break;

    case QCRYPTO_CIPHER_MODE_CBC:
        cbc_decrypt(ctx->ctx_decrypt ? ctx->ctx_decrypt : ctx->ctx_encrypt,
                    ctx->alg_decrypt, ctx->niv, ctx->iv,
                    len, out, in);
        break;
    default:
        error_setg(errp, "Unsupported cipher algorithm %d",
                   cipher->alg);
        return -1;
    }
    return 0;
}

int qcrypto_cipher_setiv(QCryptoCipher *cipher,
                         const uint8_t *iv, size_t niv,
                         Error **errp)
{
    QCryptoCipherNettle *ctx = cipher->opaque;
    if (niv != ctx->niv) {
        error_setg(errp, "Expected IV size %zu not %zu",
                   ctx->niv, niv);
        return -1;
    }
    memcpy(ctx->iv, iv, niv);
    return 0;
}
Commit	Line	Data
ed754746 DB	1	/*
	2	* QEMU Crypto cipher nettle algorithms
	3	*
	4	* Copyright (c) 2015 Red Hat, Inc.
	5	*
	6	* This library is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU Lesser General Public
	8	* License as published by the Free Software Foundation; either
	9	* version 2 of the License, or (at your option) any later version.
	10	*
	11	* This library is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	* Lesser General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU Lesser General Public
	17	* License along with this library; if not, see <http://www.gnu.org/licenses/>.
	18	*
	19	*/
	20
	21	#include <nettle/nettle-types.h>
	22	#include <nettle/aes.h>
	23	#include <nettle/des.h>
	24	#include <nettle/cbc.h>
	25
becaeb72 RK	26	#if CONFIG_NETTLE_VERSION_MAJOR < 3
becaeb72 RK	27	typedef nettle_crypt_func nettle_cipher_func;
d3462e37 RK	28
	29	typedef void * cipher_ctx_t;
	30	typedef unsigned cipher_length_t;
	31	#else
	32	typedef const void * cipher_ctx_t;
	33	typedef size_t cipher_length_t;
becaeb72 RK	34	#endif
becaeb72 RK	35
d3462e37 RK	36	static nettle_cipher_func aes_encrypt_wrapper;
	37	static nettle_cipher_func aes_decrypt_wrapper;
	38	static nettle_cipher_func des_encrypt_wrapper;
	39	static nettle_cipher_func des_decrypt_wrapper;
	40
	41	static void aes_encrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
	42	uint8_t dst, const uint8_t src)
	43	{
	44	aes_encrypt(ctx, length, dst, src);
	45	}
	46
	47	static void aes_decrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
	48	uint8_t dst, const uint8_t src)
	49	{
bd095946	50	aes_decrypt(ctx, length, dst, src);
d3462e37 RK	51	}
	52
	53	static void des_encrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
	54	uint8_t dst, const uint8_t src)
	55	{
	56	des_encrypt(ctx, length, dst, src);
	57	}
	58
	59	static void des_decrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
	60	uint8_t dst, const uint8_t src)
	61	{
	62	des_decrypt(ctx, length, dst, src);
	63	}
	64
ed754746 DB	65	typedef struct QCryptoCipherNettle QCryptoCipherNettle;
	66	struct QCryptoCipherNettle {
	67	void *ctx_encrypt;
	68	void *ctx_decrypt;
becaeb72 RK	69	nettle_cipher_func *alg_encrypt;
becaeb72 RK	70	nettle_cipher_func *alg_decrypt;
ed754746 DB	71	uint8_t *iv;
	72	size_t niv;
	73	};
	74
	75	bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg)
	76	{
	77	switch (alg) {
	78	case QCRYPTO_CIPHER_ALG_DES_RFB:
	79	case QCRYPTO_CIPHER_ALG_AES_128:
	80	case QCRYPTO_CIPHER_ALG_AES_192:
	81	case QCRYPTO_CIPHER_ALG_AES_256:
	82	return true;
	83	default:
	84	return false;
	85	}
	86	}
	87
	88
	89	QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
	90	QCryptoCipherMode mode,
	91	const uint8_t *key, size_t nkey,
	92	Error **errp)
	93	{
	94	QCryptoCipher *cipher;
	95	QCryptoCipherNettle *ctx;
	96	uint8_t *rfbkey;
	97
	98	switch (mode) {
	99	case QCRYPTO_CIPHER_MODE_ECB:
	100	case QCRYPTO_CIPHER_MODE_CBC:
	101	break;
	102	default:
	103	error_setg(errp, "Unsupported cipher mode %d", mode);
	104	return NULL;
	105	}
	106
	107	if (!qcrypto_cipher_validate_key_length(alg, nkey, errp)) {
	108	return NULL;
	109	}
	110
	111	cipher = g_new0(QCryptoCipher, 1);
	112	cipher->alg = alg;
	113	cipher->mode = mode;
	114
	115	ctx = g_new0(QCryptoCipherNettle, 1);
	116
	117	switch (alg) {
	118	case QCRYPTO_CIPHER_ALG_DES_RFB:
	119	ctx->ctx_encrypt = g_new0(struct des_ctx, 1);
	120	ctx->ctx_decrypt = NULL; /* 1 ctx can do both */
	121	rfbkey = qcrypto_cipher_munge_des_rfb_key(key, nkey);
	122	des_set_key(ctx->ctx_encrypt, rfbkey);
	123	g_free(rfbkey);
	124
d3462e37 RK	125	ctx->alg_encrypt = des_encrypt_wrapper;
d3462e37 RK	126	ctx->alg_decrypt = des_decrypt_wrapper;
ed754746 DB	127
	128	ctx->niv = DES_BLOCK_SIZE;
	129	break;
	130
	131	case QCRYPTO_CIPHER_ALG_AES_128:
	132	case QCRYPTO_CIPHER_ALG_AES_192:
	133	case QCRYPTO_CIPHER_ALG_AES_256:
	134	ctx->ctx_encrypt = g_new0(struct aes_ctx, 1);
	135	ctx->ctx_decrypt = g_new0(struct aes_ctx, 1);
	136
	137	aes_set_encrypt_key(ctx->ctx_encrypt, nkey, key);
	138	aes_set_decrypt_key(ctx->ctx_decrypt, nkey, key);
	139
d3462e37 RK	140	ctx->alg_encrypt = aes_encrypt_wrapper;
d3462e37 RK	141	ctx->alg_decrypt = aes_decrypt_wrapper;
ed754746 DB	142
	143	ctx->niv = AES_BLOCK_SIZE;
	144	break;
	145	default:
	146	error_setg(errp, "Unsupported cipher algorithm %d", alg);
	147	goto error;
	148	}
	149
	150	ctx->iv = g_new0(uint8_t, ctx->niv);
	151	cipher->opaque = ctx;
	152
	153	return cipher;
	154
	155	error:
	156	g_free(cipher);
	157	g_free(ctx);
	158	return NULL;
	159	}
	160
	161
	162	void qcrypto_cipher_free(QCryptoCipher *cipher)
	163	{
	164	QCryptoCipherNettle *ctx;
	165
	166	if (!cipher) {
	167	return;
	168	}
	169
	170	ctx = cipher->opaque;
	171	g_free(ctx->iv);
	172	g_free(ctx->ctx_encrypt);
	173	g_free(ctx->ctx_decrypt);
	174	g_free(ctx);
	175	g_free(cipher);
	176	}
	177
	178
	179	int qcrypto_cipher_encrypt(QCryptoCipher *cipher,
	180	const void *in,
	181	void *out,
	182	size_t len,
	183	Error **errp)
	184	{
	185	QCryptoCipherNettle *ctx = cipher->opaque;
	186
	187	switch (cipher->mode) {
	188	case QCRYPTO_CIPHER_MODE_ECB:
	189	ctx->alg_encrypt(ctx->ctx_encrypt, len, out, in);
	190	break;
	191
	192	case QCRYPTO_CIPHER_MODE_CBC:
	193	cbc_encrypt(ctx->ctx_encrypt, ctx->alg_encrypt,
	194	ctx->niv, ctx->iv,
	195	len, out, in);
	196	break;
	197	default:
	198	error_setg(errp, "Unsupported cipher algorithm %d",
	199	cipher->alg);
	200	return -1;
	201	}
	202	return 0;
	203	}
	204
	205
206	int qcrypto_cipher_decrypt(QCryptoCipher *cipher,
207	const void *in,
208	void *out,
209	size_t len,
210	Error **errp)
211	{
212	QCryptoCipherNettle *ctx = cipher->opaque;
213
214	switch (cipher->mode) {
215	case QCRYPTO_CIPHER_MODE_ECB:
216	ctx->alg_decrypt(ctx->ctx_decrypt ? ctx->ctx_decrypt : ctx->ctx_encrypt,
217	len, out, in);
218	break;
219
220	case QCRYPTO_CIPHER_MODE_CBC:
221	cbc_decrypt(ctx->ctx_decrypt ? ctx->ctx_decrypt : ctx->ctx_encrypt,
222	ctx->alg_decrypt, ctx->niv, ctx->iv,
223	len, out, in);
224	break;
225	default:
226	error_setg(errp, "Unsupported cipher algorithm %d",
227	cipher->alg);
228	return -1;
229	}
230	return 0;
231	}
232
233	int qcrypto_cipher_setiv(QCryptoCipher *cipher,
234	const uint8_t *iv, size_t niv,
235	Error **errp)
236	{
237	QCryptoCipherNettle *ctx = cipher->opaque;
238	if (niv != ctx->niv) {
239	error_setg(errp, "Expected IV size %zu not %zu",
240	ctx->niv, niv);
241	return -1;
242	}
243	memcpy(ctx->iv, iv, niv);
244	return 0;
245	}