/*!
* Generates CC_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 cc_gen_iv_pool(struct cc_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 + CC_IVPOOL_GEN_SEQ_LEN) > CC_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, CC_IVPOOL_SIZE);
set_dout_sram(&iv_seq[idx], ivgen_ctx->pool, CC_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 = CC_IVPOOL_META_SIZE;
return 0;
}
/*!
* Generates the initial pool in SRAM.
* This function should be invoked when resuming driver.
*
* \param drvdata
*
* \return int Zero for success, negative value otherwise.
*/
int cc_init_iv_sram(struct cc_drvdata *drvdata)
{
struct cc_ivgen_ctx *ivgen_ctx = drvdata->ivgen_handle;
struct cc_hw_desc iv_seq[CC_IVPOOL_SEQ_LEN];
unsigned int iv_seq_len = 0;
int rc;
/* Generate initial enc. key/iv */
get_random_bytes(ivgen_ctx->pool_meta, CC_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,
CC_IVPOOL_META_SIZE, NS_BIT);
set_dout_sram(&iv_seq[iv_seq_len], ivgen_ctx->pool,
CC_IVPOOL_META_SIZE);
set_flow_mode(&iv_seq[iv_seq_len], BYPASS);
iv_seq_len++;
/* Generate initial pool */
rc = cc_gen_iv_pool(ivgen_ctx, iv_seq, &iv_seq_len);
if (rc)
return rc;
/* Fire-and-forget */
return send_request_init(drvdata, iv_seq, iv_seq_len);
}
/**
* ssi_sram_mgr_const2sram_desc() - Create const descriptors sequence to
* set values in given array into SRAM.
* Note: each const value can't exceed word size.
*
* @src: A pointer to array of words to set as consts.
* @dst: The target SRAM buffer to set into
* @nelements: The number of words in "src" array
* @seq: A pointer to the given IN/OUT descriptor sequence
* @seq_len: A pointer to the given IN/OUT sequence length
*/
void ssi_sram_mgr_const2sram_desc(
const u32 *src, ssi_sram_addr_t dst,
unsigned int nelement,
struct cc_hw_desc *seq, unsigned int *seq_len)
{
u32 i;
unsigned int idx = *seq_len;
for (i = 0; i < nelement; i++, idx++) {
hw_desc_init(&seq[idx]);
set_din_const(&seq[idx], src[i], sizeof(u32));
set_dout_sram(&seq[idx], dst + (i * sizeof(u32)), sizeof(u32));
set_flow_mode(&seq[idx], BYPASS);
}
*seq_len = idx;
}
