Exemple #1
0
static int __driver_rfc4106_decrypt(struct aead_request *req)
{
	u8 one_entry_in_sg = 0;
	u8 *src, *dst, *assoc;
	unsigned long tempCipherLen = 0;
	__be32 counter = cpu_to_be32(1);
	int retval = 0;
	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
	struct aesni_rfc4106_gcm_ctx *ctx = aesni_rfc4106_gcm_ctx_get(tfm);
	void *aes_ctx = &(ctx->aes_key_expanded);
	unsigned long auth_tag_len = crypto_aead_authsize(tfm);
	u8 iv_and_authTag[32+AESNI_ALIGN];
	u8 *iv = (u8 *) PTR_ALIGN((u8 *)iv_and_authTag, AESNI_ALIGN);
	u8 *authTag = iv + 16;
	struct scatter_walk src_sg_walk;
	struct scatter_walk assoc_sg_walk;
	struct scatter_walk dst_sg_walk;
	unsigned int i;

	if (unlikely((req->cryptlen < auth_tag_len) ||
		(req->assoclen != 8 && req->assoclen != 12)))
		return -EINVAL;
	/* Assuming we are supporting rfc4106 64-bit extended */
	/* sequence numbers We need to have the AAD length */
	/* equal to 8 or 12 bytes */

	tempCipherLen = (unsigned long)(req->cryptlen - auth_tag_len);
	/* IV below built */
	for (i = 0; i < 4; i++)
		*(iv+i) = ctx->nonce[i];
	for (i = 0; i < 8; i++)
		*(iv+4+i) = req->iv[i];
	*((__be32 *)(iv+12)) = counter;

	if ((sg_is_last(req->src)) && (sg_is_last(req->assoc))) {
		one_entry_in_sg = 1;
		scatterwalk_start(&src_sg_walk, req->src);
		scatterwalk_start(&assoc_sg_walk, req->assoc);
		src = scatterwalk_map(&src_sg_walk);
		assoc = scatterwalk_map(&assoc_sg_walk);
		dst = src;
		if (unlikely(req->src != req->dst)) {
			scatterwalk_start(&dst_sg_walk, req->dst);
			dst = scatterwalk_map(&dst_sg_walk);
		}

	} else {
		/* Allocate memory for src, dst, assoc */
		src = kmalloc(req->cryptlen + req->assoclen, GFP_ATOMIC);
		if (!src)
			return -ENOMEM;
		assoc = (src + req->cryptlen + auth_tag_len);
		scatterwalk_map_and_copy(src, req->src, 0, req->cryptlen, 0);
		scatterwalk_map_and_copy(assoc, req->assoc, 0,
			req->assoclen, 0);
		dst = src;
	}

	aesni_gcm_dec_tfm(aes_ctx, dst, src, tempCipherLen, iv,
		ctx->hash_subkey, assoc, (unsigned long)req->assoclen,
		authTag, auth_tag_len);

	/* Compare generated tag with passed in tag. */
	retval = crypto_memneq(src + tempCipherLen, authTag, auth_tag_len) ?
		-EBADMSG : 0;

	if (one_entry_in_sg) {
		if (unlikely(req->src != req->dst)) {
			scatterwalk_unmap(dst);
			scatterwalk_done(&dst_sg_walk, 0, 0);
		}
		scatterwalk_unmap(src);
		scatterwalk_unmap(assoc);
		scatterwalk_done(&src_sg_walk, 0, 0);
		scatterwalk_done(&assoc_sg_walk, 0, 0);
	} else {
		scatterwalk_map_and_copy(dst, req->dst, 0, req->cryptlen, 1);
		kfree(src);
	}
	return retval;
}
static int xts_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
		       struct scatterlist *src, unsigned int nbytes)
{
	struct aesni_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	be128 buf[8];
	struct xts_crypt_req req = {
		.tbuf = buf,
		.tbuflen = sizeof(buf),

		.tweak_ctx = aes_ctx(ctx->raw_tweak_ctx),
		.tweak_fn = aesni_xts_tweak,
		.crypt_ctx = aes_ctx(ctx->raw_crypt_ctx),
		.crypt_fn = lrw_xts_encrypt_callback,
	};
	int ret;

	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;

	kernel_fpu_begin();
	ret = xts_crypt(desc, dst, src, nbytes, &req);
	kernel_fpu_end();

	return ret;
}

static int xts_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
		       struct scatterlist *src, unsigned int nbytes)
{
	struct aesni_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	be128 buf[8];
	struct xts_crypt_req req = {
		.tbuf = buf,
		.tbuflen = sizeof(buf),

		.tweak_ctx = aes_ctx(ctx->raw_tweak_ctx),
		.tweak_fn = aesni_xts_tweak,
		.crypt_ctx = aes_ctx(ctx->raw_crypt_ctx),
		.crypt_fn = lrw_xts_decrypt_callback,
	};
	int ret;

	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;

	kernel_fpu_begin();
	ret = xts_crypt(desc, dst, src, nbytes, &req);
	kernel_fpu_end();

	return ret;
}

#endif

#ifdef CONFIG_X86_64
static int rfc4106_init(struct crypto_aead *aead)
{
	struct cryptd_aead *cryptd_tfm;
	struct cryptd_aead **ctx = crypto_aead_ctx(aead);

	cryptd_tfm = cryptd_alloc_aead("__driver-gcm-aes-aesni",
				       CRYPTO_ALG_INTERNAL,
				       CRYPTO_ALG_INTERNAL);
	if (IS_ERR(cryptd_tfm))
		return PTR_ERR(cryptd_tfm);

	*ctx = cryptd_tfm;
	crypto_aead_set_reqsize(aead, crypto_aead_reqsize(&cryptd_tfm->base));
	return 0;
}

static void rfc4106_exit(struct crypto_aead *aead)
{
	struct cryptd_aead **ctx = crypto_aead_ctx(aead);

	cryptd_free_aead(*ctx);
}

static int
rfc4106_set_hash_subkey(u8 *hash_subkey, const u8 *key, unsigned int key_len)
{
	struct crypto_cipher *tfm;
	int ret;

	tfm = crypto_alloc_cipher("aes", 0, 0);
	if (IS_ERR(tfm))
		return PTR_ERR(tfm);

	ret = crypto_cipher_setkey(tfm, key, key_len);
	if (ret)
		goto out_free_cipher;

	/* Clear the data in the hash sub key container to zero.*/
	/* We want to cipher all zeros to create the hash sub key. */
	memset(hash_subkey, 0, RFC4106_HASH_SUBKEY_SIZE);

	crypto_cipher_encrypt_one(tfm, hash_subkey, hash_subkey);

out_free_cipher:
	crypto_free_cipher(tfm);
	return ret;
}

static int common_rfc4106_set_key(struct crypto_aead *aead, const u8 *key,
				  unsigned int key_len)
{
	struct aesni_rfc4106_gcm_ctx *ctx = aesni_rfc4106_gcm_ctx_get(aead);

	if (key_len < 4) {
		crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN);
		return -EINVAL;
	}
	/*Account for 4 byte nonce at the end.*/
	key_len -= 4;

	memcpy(ctx->nonce, key + key_len, sizeof(ctx->nonce));

	return aes_set_key_common(crypto_aead_tfm(aead),
				  &ctx->aes_key_expanded, key, key_len) ?:
	       rfc4106_set_hash_subkey(ctx->hash_subkey, key, key_len);
}

static int rfc4106_set_key(struct crypto_aead *parent, const u8 *key,
			   unsigned int key_len)
{
	struct cryptd_aead **ctx = crypto_aead_ctx(parent);
	struct cryptd_aead *cryptd_tfm = *ctx;

	return crypto_aead_setkey(&cryptd_tfm->base, key, key_len);
}

static int common_rfc4106_set_authsize(struct crypto_aead *aead,
				       unsigned int authsize)
{
	switch (authsize) {
	case 8:
	case 12:
	case 16:
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

/* This is the Integrity Check Value (aka the authentication tag length and can
 * be 8, 12 or 16 bytes long. */
static int rfc4106_set_authsize(struct crypto_aead *parent,
				unsigned int authsize)
{
	struct cryptd_aead **ctx = crypto_aead_ctx(parent);
	struct cryptd_aead *cryptd_tfm = *ctx;

	return crypto_aead_setauthsize(&cryptd_tfm->base, authsize);
}

static int helper_rfc4106_encrypt(struct aead_request *req)
{
	u8 one_entry_in_sg = 0;
	u8 *src, *dst, *assoc;
	__be32 counter = cpu_to_be32(1);
	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
	struct aesni_rfc4106_gcm_ctx *ctx = aesni_rfc4106_gcm_ctx_get(tfm);
	void *aes_ctx = &(ctx->aes_key_expanded);
	unsigned long auth_tag_len = crypto_aead_authsize(tfm);
	u8 iv[16] __attribute__ ((__aligned__(AESNI_ALIGN)));
	struct scatter_walk src_sg_walk;
	struct scatter_walk dst_sg_walk = {};
	unsigned int i;

	/* Assuming we are supporting rfc4106 64-bit extended */
	/* sequence numbers We need to have the AAD length equal */
	/* to 16 or 20 bytes */
	if (unlikely(req->assoclen != 16 && req->assoclen != 20))
		return -EINVAL;

	/* IV below built */
	for (i = 0; i < 4; i++)
		*(iv+i) = ctx->nonce[i];
	for (i = 0; i < 8; i++)
		*(iv+4+i) = req->iv[i];
	*((__be32 *)(iv+12)) = counter;

	if (sg_is_last(req->src) &&
	    req->src->offset + req->src->length <= PAGE_SIZE &&
	    sg_is_last(req->dst) &&
	    req->dst->offset + req->dst->length <= PAGE_SIZE) {
		one_entry_in_sg = 1;
		scatterwalk_start(&src_sg_walk, req->src);
		assoc = scatterwalk_map(&src_sg_walk);
		src = assoc + req->assoclen;
		dst = src;
		if (unlikely(req->src != req->dst)) {
			scatterwalk_start(&dst_sg_walk, req->dst);
			dst = scatterwalk_map(&dst_sg_walk) + req->assoclen;
		}
	} else {
		/* Allocate memory for src, dst, assoc */
		assoc = kmalloc(req->cryptlen + auth_tag_len + req->assoclen,
			GFP_ATOMIC);
		if (unlikely(!assoc))
			return -ENOMEM;
		scatterwalk_map_and_copy(assoc, req->src, 0,
					 req->assoclen + req->cryptlen, 0);
		src = assoc + req->assoclen;
		dst = src;
	}

	kernel_fpu_begin();
	aesni_gcm_enc_tfm(aes_ctx, dst, src, req->cryptlen, iv,
			  ctx->hash_subkey, assoc, req->assoclen - 8,
			  dst + req->cryptlen, auth_tag_len);
	kernel_fpu_end();

	/* The authTag (aka the Integrity Check Value) needs to be written
	 * back to the packet. */
	if (one_entry_in_sg) {
		if (unlikely(req->src != req->dst)) {
			scatterwalk_unmap(dst - req->assoclen);
			scatterwalk_advance(&dst_sg_walk, req->dst->length);
			scatterwalk_done(&dst_sg_walk, 1, 0);
		}
		scatterwalk_unmap(assoc);
		scatterwalk_advance(&src_sg_walk, req->src->length);
		scatterwalk_done(&src_sg_walk, req->src == req->dst, 0);
	} else {
		scatterwalk_map_and_copy(dst, req->dst, req->assoclen,
					 req->cryptlen + auth_tag_len, 1);
		kfree(assoc);
	}
	return 0;
}

static int helper_rfc4106_decrypt(struct aead_request *req)
{
	u8 one_entry_in_sg = 0;
	u8 *src, *dst, *assoc;
	unsigned long tempCipherLen = 0;
	__be32 counter = cpu_to_be32(1);
	int retval = 0;
	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
	struct aesni_rfc4106_gcm_ctx *ctx = aesni_rfc4106_gcm_ctx_get(tfm);
	void *aes_ctx = &(ctx->aes_key_expanded);
	unsigned long auth_tag_len = crypto_aead_authsize(tfm);
	u8 iv[16] __attribute__ ((__aligned__(AESNI_ALIGN)));
	u8 authTag[16];
	struct scatter_walk src_sg_walk;
	struct scatter_walk dst_sg_walk = {};
	unsigned int i;

	if (unlikely(req->assoclen != 16 && req->assoclen != 20))
		return -EINVAL;

	/* Assuming we are supporting rfc4106 64-bit extended */
	/* sequence numbers We need to have the AAD length */
	/* equal to 16 or 20 bytes */

	tempCipherLen = (unsigned long)(req->cryptlen - auth_tag_len);
	/* IV below built */
	for (i = 0; i < 4; i++)
		*(iv+i) = ctx->nonce[i];
	for (i = 0; i < 8; i++)
		*(iv+4+i) = req->iv[i];
	*((__be32 *)(iv+12)) = counter;

	if (sg_is_last(req->src) &&
	    req->src->offset + req->src->length <= PAGE_SIZE &&
	    sg_is_last(req->dst) &&
	    req->dst->offset + req->dst->length <= PAGE_SIZE) {
		one_entry_in_sg = 1;
		scatterwalk_start(&src_sg_walk, req->src);
		assoc = scatterwalk_map(&src_sg_walk);
		src = assoc + req->assoclen;
		dst = src;
		if (unlikely(req->src != req->dst)) {
			scatterwalk_start(&dst_sg_walk, req->dst);
			dst = scatterwalk_map(&dst_sg_walk) + req->assoclen;
		}

	} else {
		/* Allocate memory for src, dst, assoc */
		assoc = kmalloc(req->cryptlen + req->assoclen, GFP_ATOMIC);
		if (!assoc)
			return -ENOMEM;
		scatterwalk_map_and_copy(assoc, req->src, 0,
					 req->assoclen + req->cryptlen, 0);
		src = assoc + req->assoclen;
		dst = src;
	}

	kernel_fpu_begin();
	aesni_gcm_dec_tfm(aes_ctx, dst, src, tempCipherLen, iv,
			  ctx->hash_subkey, assoc, req->assoclen - 8,
			  authTag, auth_tag_len);
	kernel_fpu_end();

	/* Compare generated tag with passed in tag. */
	retval = crypto_memneq(src + tempCipherLen, authTag, auth_tag_len) ?
		-EBADMSG : 0;

	if (one_entry_in_sg) {
		if (unlikely(req->src != req->dst)) {
			scatterwalk_unmap(dst - req->assoclen);
			scatterwalk_advance(&dst_sg_walk, req->dst->length);
			scatterwalk_done(&dst_sg_walk, 1, 0);
		}
		scatterwalk_unmap(assoc);
		scatterwalk_advance(&src_sg_walk, req->src->length);
		scatterwalk_done(&src_sg_walk, req->src == req->dst, 0);
	} else {
		scatterwalk_map_and_copy(dst, req->dst, req->assoclen,
					 tempCipherLen, 1);
		kfree(assoc);
	}
	return retval;
}
static int gcmaes_decrypt(struct aead_request *req, unsigned int assoclen,
			  u8 *hash_subkey, u8 *iv, void *aes_ctx)
{
	u8 one_entry_in_sg = 0;
	u8 *src, *dst, *assoc;
	unsigned long tempCipherLen = 0;
	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
	unsigned long auth_tag_len = crypto_aead_authsize(tfm);
	u8 authTag[16];
	struct scatter_walk src_sg_walk;
	struct scatter_walk dst_sg_walk = {};
	int retval = 0;

	tempCipherLen = (unsigned long)(req->cryptlen - auth_tag_len);

	if (sg_is_last(req->src) &&
	    (!PageHighMem(sg_page(req->src)) ||
	    req->src->offset + req->src->length <= PAGE_SIZE) &&
	    sg_is_last(req->dst) &&
	    (!PageHighMem(sg_page(req->dst)) ||
	    req->dst->offset + req->dst->length <= PAGE_SIZE)) {
		one_entry_in_sg = 1;
		scatterwalk_start(&src_sg_walk, req->src);
		assoc = scatterwalk_map(&src_sg_walk);
		src = assoc + req->assoclen;
		dst = src;
		if (unlikely(req->src != req->dst)) {
			scatterwalk_start(&dst_sg_walk, req->dst);
			dst = scatterwalk_map(&dst_sg_walk) + req->assoclen;
		}
	} else {
		/* Allocate memory for src, dst, assoc */
		assoc = kmalloc(req->cryptlen + req->assoclen, GFP_ATOMIC);
		if (!assoc)
			return -ENOMEM;
		scatterwalk_map_and_copy(assoc, req->src, 0,
					 req->assoclen + req->cryptlen, 0);
		src = assoc + req->assoclen;
		dst = src;
	}


	kernel_fpu_begin();
	aesni_gcm_dec_tfm(aes_ctx, dst, src, tempCipherLen, iv,
			  hash_subkey, assoc, assoclen,
			  authTag, auth_tag_len);
	kernel_fpu_end();

	/* Compare generated tag with passed in tag. */
	retval = crypto_memneq(src + tempCipherLen, authTag, auth_tag_len) ?
		-EBADMSG : 0;

	if (one_entry_in_sg) {
		if (unlikely(req->src != req->dst)) {
			scatterwalk_unmap(dst - req->assoclen);
			scatterwalk_advance(&dst_sg_walk, req->dst->length);
			scatterwalk_done(&dst_sg_walk, 1, 0);
		}
		scatterwalk_unmap(assoc);
		scatterwalk_advance(&src_sg_walk, req->src->length);
		scatterwalk_done(&src_sg_walk, req->src == req->dst, 0);
	} else {
		scatterwalk_map_and_copy(dst, req->dst, req->assoclen,
					 tempCipherLen, 1);
		kfree(assoc);
	}
	return retval;

}