299 lines
8.7 KiB
C
299 lines
8.7 KiB
C
/*
|
|
* Copyright (C) 2012-2017 ARM Limited or its affiliates.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* 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, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <linux/platform_device.h>
|
|
#include <crypto/ctr.h>
|
|
#include "ssi_config.h"
|
|
#include "ssi_driver.h"
|
|
#include "ssi_ivgen.h"
|
|
#include "ssi_request_mgr.h"
|
|
#include "ssi_sram_mgr.h"
|
|
#include "ssi_buffer_mgr.h"
|
|
|
|
/* The max. size of pool *MUST* be <= SRAM total size */
|
|
#define SSI_IVPOOL_SIZE 1024
|
|
/* The first 32B fraction of pool are dedicated to the
|
|
* next encryption "key" & "IV" for pool regeneration
|
|
*/
|
|
#define SSI_IVPOOL_META_SIZE (CC_AES_IV_SIZE + AES_KEYSIZE_128)
|
|
#define SSI_IVPOOL_GEN_SEQ_LEN 4
|
|
|
|
/**
|
|
* struct ssi_ivgen_ctx -IV pool generation context
|
|
* @pool: the start address of the iv-pool resides in internal RAM
|
|
* @ctr_key_dma: address of pool's encryption key material in internal RAM
|
|
* @ctr_iv_dma: address of pool's counter iv in internal RAM
|
|
* @next_iv_ofs: the offset to the next available IV in pool
|
|
* @pool_meta: virt. address of the initial enc. key/IV
|
|
* @pool_meta_dma: phys. address of the initial enc. key/IV
|
|
*/
|
|
struct ssi_ivgen_ctx {
|
|
ssi_sram_addr_t pool;
|
|
ssi_sram_addr_t ctr_key;
|
|
ssi_sram_addr_t ctr_iv;
|
|
u32 next_iv_ofs;
|
|
u8 *pool_meta;
|
|
dma_addr_t pool_meta_dma;
|
|
};
|
|
|
|
/*!
|
|
* Generates SSI_IVPOOL_SIZE of random bytes by
|
|
* encrypting 0's using AES128-CTR.
|
|
*
|
|
* \param ivgen iv-pool context
|
|
* \param iv_seq IN/OUT array to the descriptors sequence
|
|
* \param iv_seq_len IN/OUT pointer to the sequence length
|
|
*/
|
|
static int ssi_ivgen_generate_pool(
|
|
struct ssi_ivgen_ctx *ivgen_ctx,
|
|
struct cc_hw_desc iv_seq[],
|
|
unsigned int *iv_seq_len)
|
|
{
|
|
unsigned int idx = *iv_seq_len;
|
|
|
|
if ((*iv_seq_len + SSI_IVPOOL_GEN_SEQ_LEN) > SSI_IVPOOL_SEQ_LEN) {
|
|
/* The sequence will be longer than allowed */
|
|
return -EINVAL;
|
|
}
|
|
/* Setup key */
|
|
hw_desc_init(&iv_seq[idx]);
|
|
set_din_sram(&iv_seq[idx], ivgen_ctx->ctr_key, AES_KEYSIZE_128);
|
|
set_setup_mode(&iv_seq[idx], SETUP_LOAD_KEY0);
|
|
set_cipher_config0(&iv_seq[idx], DESC_DIRECTION_ENCRYPT_ENCRYPT);
|
|
set_flow_mode(&iv_seq[idx], S_DIN_to_AES);
|
|
set_key_size_aes(&iv_seq[idx], CC_AES_128_BIT_KEY_SIZE);
|
|
set_cipher_mode(&iv_seq[idx], DRV_CIPHER_CTR);
|
|
idx++;
|
|
|
|
/* Setup cipher state */
|
|
hw_desc_init(&iv_seq[idx]);
|
|
set_din_sram(&iv_seq[idx], ivgen_ctx->ctr_iv, CC_AES_IV_SIZE);
|
|
set_cipher_config0(&iv_seq[idx], DESC_DIRECTION_ENCRYPT_ENCRYPT);
|
|
set_flow_mode(&iv_seq[idx], S_DIN_to_AES);
|
|
set_setup_mode(&iv_seq[idx], SETUP_LOAD_STATE1);
|
|
set_key_size_aes(&iv_seq[idx], CC_AES_128_BIT_KEY_SIZE);
|
|
set_cipher_mode(&iv_seq[idx], DRV_CIPHER_CTR);
|
|
idx++;
|
|
|
|
/* Perform dummy encrypt to skip first block */
|
|
hw_desc_init(&iv_seq[idx]);
|
|
set_din_const(&iv_seq[idx], 0, CC_AES_IV_SIZE);
|
|
set_dout_sram(&iv_seq[idx], ivgen_ctx->pool, CC_AES_IV_SIZE);
|
|
set_flow_mode(&iv_seq[idx], DIN_AES_DOUT);
|
|
idx++;
|
|
|
|
/* Generate IV pool */
|
|
hw_desc_init(&iv_seq[idx]);
|
|
set_din_const(&iv_seq[idx], 0, SSI_IVPOOL_SIZE);
|
|
set_dout_sram(&iv_seq[idx], ivgen_ctx->pool, SSI_IVPOOL_SIZE);
|
|
set_flow_mode(&iv_seq[idx], DIN_AES_DOUT);
|
|
idx++;
|
|
|
|
*iv_seq_len = idx; /* Update sequence length */
|
|
|
|
/* queue ordering assures pool readiness */
|
|
ivgen_ctx->next_iv_ofs = SSI_IVPOOL_META_SIZE;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*!
|
|
* Generates the initial pool in SRAM.
|
|
* This function should be invoked when resuming DX driver.
|
|
*
|
|
* \param drvdata
|
|
*
|
|
* \return int Zero for success, negative value otherwise.
|
|
*/
|
|
int ssi_ivgen_init_sram_pool(struct ssi_drvdata *drvdata)
|
|
{
|
|
struct ssi_ivgen_ctx *ivgen_ctx = drvdata->ivgen_handle;
|
|
struct cc_hw_desc iv_seq[SSI_IVPOOL_SEQ_LEN];
|
|
unsigned int iv_seq_len = 0;
|
|
int rc;
|
|
|
|
/* Generate initial enc. key/iv */
|
|
get_random_bytes(ivgen_ctx->pool_meta, SSI_IVPOOL_META_SIZE);
|
|
|
|
/* The first 32B reserved for the enc. Key/IV */
|
|
ivgen_ctx->ctr_key = ivgen_ctx->pool;
|
|
ivgen_ctx->ctr_iv = ivgen_ctx->pool + AES_KEYSIZE_128;
|
|
|
|
/* Copy initial enc. key and IV to SRAM at a single descriptor */
|
|
hw_desc_init(&iv_seq[iv_seq_len]);
|
|
set_din_type(&iv_seq[iv_seq_len], DMA_DLLI, ivgen_ctx->pool_meta_dma,
|
|
SSI_IVPOOL_META_SIZE, NS_BIT);
|
|
set_dout_sram(&iv_seq[iv_seq_len], ivgen_ctx->pool,
|
|
SSI_IVPOOL_META_SIZE);
|
|
set_flow_mode(&iv_seq[iv_seq_len], BYPASS);
|
|
iv_seq_len++;
|
|
|
|
/* Generate initial pool */
|
|
rc = ssi_ivgen_generate_pool(ivgen_ctx, iv_seq, &iv_seq_len);
|
|
if (unlikely(rc != 0))
|
|
return rc;
|
|
|
|
/* Fire-and-forget */
|
|
return send_request_init(drvdata, iv_seq, iv_seq_len);
|
|
}
|
|
|
|
/*!
|
|
* Free iv-pool and ivgen context.
|
|
*
|
|
* \param drvdata
|
|
*/
|
|
void ssi_ivgen_fini(struct ssi_drvdata *drvdata)
|
|
{
|
|
struct ssi_ivgen_ctx *ivgen_ctx = drvdata->ivgen_handle;
|
|
struct device *device = &(drvdata->plat_dev->dev);
|
|
|
|
if (!ivgen_ctx)
|
|
return;
|
|
|
|
if (ivgen_ctx->pool_meta) {
|
|
memset(ivgen_ctx->pool_meta, 0, SSI_IVPOOL_META_SIZE);
|
|
dma_free_coherent(device, SSI_IVPOOL_META_SIZE,
|
|
ivgen_ctx->pool_meta, ivgen_ctx->pool_meta_dma);
|
|
}
|
|
|
|
ivgen_ctx->pool = NULL_SRAM_ADDR;
|
|
|
|
/* release "this" context */
|
|
kfree(ivgen_ctx);
|
|
}
|
|
|
|
/*!
|
|
* Allocates iv-pool and maps resources.
|
|
* This function generates the first IV pool.
|
|
*
|
|
* \param drvdata Driver's private context
|
|
*
|
|
* \return int Zero for success, negative value otherwise.
|
|
*/
|
|
int ssi_ivgen_init(struct ssi_drvdata *drvdata)
|
|
{
|
|
struct ssi_ivgen_ctx *ivgen_ctx;
|
|
struct device *device = &drvdata->plat_dev->dev;
|
|
int rc;
|
|
|
|
/* Allocate "this" context */
|
|
drvdata->ivgen_handle = kzalloc(sizeof(struct ssi_ivgen_ctx), GFP_KERNEL);
|
|
if (!drvdata->ivgen_handle) {
|
|
SSI_LOG_ERR("Not enough memory to allocate IVGEN context "
|
|
"(%zu B)\n", sizeof(struct ssi_ivgen_ctx));
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
ivgen_ctx = drvdata->ivgen_handle;
|
|
|
|
/* Allocate pool's header for intial enc. key/IV */
|
|
ivgen_ctx->pool_meta = dma_alloc_coherent(device, SSI_IVPOOL_META_SIZE,
|
|
&ivgen_ctx->pool_meta_dma, GFP_KERNEL);
|
|
if (!ivgen_ctx->pool_meta) {
|
|
SSI_LOG_ERR("Not enough memory to allocate DMA of pool_meta "
|
|
"(%u B)\n", SSI_IVPOOL_META_SIZE);
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
/* Allocate IV pool in SRAM */
|
|
ivgen_ctx->pool = ssi_sram_mgr_alloc(drvdata, SSI_IVPOOL_SIZE);
|
|
if (ivgen_ctx->pool == NULL_SRAM_ADDR) {
|
|
SSI_LOG_ERR("SRAM pool exhausted\n");
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
return ssi_ivgen_init_sram_pool(drvdata);
|
|
|
|
out:
|
|
ssi_ivgen_fini(drvdata);
|
|
return rc;
|
|
}
|
|
|
|
/*!
|
|
* Acquires 16 Bytes IV from the iv-pool
|
|
*
|
|
* \param drvdata Driver private context
|
|
* \param iv_out_dma Array of physical IV out addresses
|
|
* \param iv_out_dma_len Length of iv_out_dma array (additional elements of iv_out_dma array are ignore)
|
|
* \param iv_out_size May be 8 or 16 bytes long
|
|
* \param iv_seq IN/OUT array to the descriptors sequence
|
|
* \param iv_seq_len IN/OUT pointer to the sequence length
|
|
*
|
|
* \return int Zero for success, negative value otherwise.
|
|
*/
|
|
int ssi_ivgen_getiv(
|
|
struct ssi_drvdata *drvdata,
|
|
dma_addr_t iv_out_dma[],
|
|
unsigned int iv_out_dma_len,
|
|
unsigned int iv_out_size,
|
|
struct cc_hw_desc iv_seq[],
|
|
unsigned int *iv_seq_len)
|
|
{
|
|
struct ssi_ivgen_ctx *ivgen_ctx = drvdata->ivgen_handle;
|
|
unsigned int idx = *iv_seq_len;
|
|
unsigned int t;
|
|
|
|
if ((iv_out_size != CC_AES_IV_SIZE) &&
|
|
(iv_out_size != CTR_RFC3686_IV_SIZE)) {
|
|
return -EINVAL;
|
|
}
|
|
if ((iv_out_dma_len + 1) > SSI_IVPOOL_SEQ_LEN) {
|
|
/* The sequence will be longer than allowed */
|
|
return -EINVAL;
|
|
}
|
|
|
|
//check that number of generated IV is limited to max dma address iv buffer size
|
|
if (iv_out_dma_len > SSI_MAX_IVGEN_DMA_ADDRESSES) {
|
|
/* The sequence will be longer than allowed */
|
|
return -EINVAL;
|
|
}
|
|
|
|
for (t = 0; t < iv_out_dma_len; t++) {
|
|
/* Acquire IV from pool */
|
|
hw_desc_init(&iv_seq[idx]);
|
|
set_din_sram(&iv_seq[idx], (ivgen_ctx->pool +
|
|
ivgen_ctx->next_iv_ofs),
|
|
iv_out_size);
|
|
set_dout_dlli(&iv_seq[idx], iv_out_dma[t], iv_out_size,
|
|
NS_BIT, 0);
|
|
set_flow_mode(&iv_seq[idx], BYPASS);
|
|
idx++;
|
|
}
|
|
|
|
/* Bypass operation is proceeded by crypto sequence, hence must
|
|
* assure bypass-write-transaction by a memory barrier
|
|
*/
|
|
hw_desc_init(&iv_seq[idx]);
|
|
set_din_no_dma(&iv_seq[idx], 0, 0xfffff0);
|
|
set_dout_no_dma(&iv_seq[idx], 0, 0, 1);
|
|
idx++;
|
|
|
|
*iv_seq_len = idx; /* update seq length */
|
|
|
|
/* Update iv index */
|
|
ivgen_ctx->next_iv_ofs += iv_out_size;
|
|
|
|
if ((SSI_IVPOOL_SIZE - ivgen_ctx->next_iv_ofs) < CC_AES_IV_SIZE) {
|
|
SSI_LOG_DEBUG("Pool exhausted, regenerating iv-pool\n");
|
|
/* pool is drained -regenerate it! */
|
|
return ssi_ivgen_generate_pool(ivgen_ctx, iv_seq, iv_seq_len);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|