Commit e623afb4 authored by Weili Qian's avatar Weili Qian
Browse files

crypto: hisilicon/trng - support to obtain random numbers from soft algorithm 

driver inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/IBATCK


CVE: NA

----------------------------------------------------------------------

When trng device is busy and fails to apply for tfm, the driver applies for
software computed tfm to prevent task failures.

Signed-off-by: default avatarWeili Qian <qianweili@huawei.com>
Signed-off-by: default avatarJiangShui Yang <yangjiangshui@h-partners.com>
parent 9112ff5e

drivers/crypto/hisilicon/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -80,5 +80,6 @@ config CRYPTO_DEV_HISI_TRNG 
	depends on ARM64 && ACPI

	select HW_RANDOM

	select CRYPTO_RNG

	select CRYPTO_DRBG_CTR

	help

	  Support for HiSilicon TRNG Driver.

drivers/crypto/hisilicon/trng/trng.c

+47 −5
Original line number Diff line number Diff line
@@ -41,6 +41,7 @@ 
#define SEED_SHIFT_24		24

#define SEED_SHIFT_16		16

#define SEED_SHIFT_8		8

#define WAIT_PERIOD		20



struct hisi_trng_list {

	struct mutex lock;
@@ -53,6 +54,7 @@ struct hisi_trng { 
	struct hisi_trng_list *trng_list;

	struct list_head list;

	struct hwrng rng;

	u32 ctx_num;

	u32 ver;

	bool is_used;

	struct mutex mutex;
@@ -60,6 +62,7 @@ struct hisi_trng { 


struct hisi_trng_ctx {

	struct hisi_trng *trng;

	struct crypto_rng *drbg;

};



static atomic_t trng_active_devs;
@@ -85,6 +88,7 @@ static int hisi_trng_seed(struct crypto_rng *tfm, const u8 *seed, 
			  unsigned int slen)

{

	struct hisi_trng_ctx *ctx = crypto_rng_ctx(tfm);

	struct crypto_rng *drbg = ctx->drbg;

	struct hisi_trng *trng = ctx->trng;

	u32 val = 0;

	int ret = 0;
@@ -95,6 +99,12 @@ static int hisi_trng_seed(struct crypto_rng *tfm, const u8 *seed, 
		return -EINVAL;

	}



	/* when the device is busy, use soft tfm instead */

	if (drbg) {

		crypto_rng_set_entropy(drbg, seed, slen);

		return crypto_rng_reset(drbg, NULL, 0);

	}



	writel(0x0, trng->base + SW_DRBG_BLOCKS);

	hisi_trng_set_seed(trng, seed);
@@ -114,6 +124,7 @@ static int hisi_trng_generate(struct crypto_rng *tfm, const u8 *src, 
			      unsigned int slen, u8 *dstn, unsigned int dlen)

{

	struct hisi_trng_ctx *ctx = crypto_rng_ctx(tfm);

	struct crypto_rng *drbg = ctx->drbg;

	struct hisi_trng *trng = ctx->trng;

	u32 data[SW_DRBG_DATA_NUM];

	u32 currsize = 0;
@@ -127,6 +138,9 @@ static int hisi_trng_generate(struct crypto_rng *tfm, const u8 *src, 
		return -EINVAL;

	}



	if (drbg)

		return crypto_rng_generate(drbg, src, slen, dstn, dlen);



	do {

		ret = readl_relaxed_poll_timeout(trng->base + SW_DRBG_STATUS,

		     val, val & BIT(1), SLEEP_US, TIMEOUT_US);
@@ -156,19 +170,41 @@ static int hisi_trng_init(struct crypto_tfm *tfm) 
{

	struct hisi_trng_ctx *ctx = crypto_tfm_ctx(tfm);

	struct hisi_trng *trng;

	int ret = -EBUSY;

	int ret = 0;



	mutex_lock(&trng_devices.lock);

	list_for_each_entry(trng, &trng_devices.list, list) {

		if (!trng->is_used) {

			trng->is_used = true;

			trng->ctx_num++;

			ctx->trng = trng;

			ret = 0;

			break;

		}

	}

	mutex_unlock(&trng_devices.lock);



	if (!ctx->trng) {

		ctx->drbg = crypto_alloc_rng("drbg_nopr_ctr_aes256", 0, 0);

		if (IS_ERR(ctx->drbg)) {

			pr_err("Can not alloc rng!\n");

			ret = PTR_ERR(ctx->drbg);

			return ret;

		}



		mutex_lock(&trng_devices.lock);

		if (list_empty(&trng_devices.list)) {

			mutex_unlock(&trng_devices.lock);

			crypto_free_rng(ctx->drbg);

			return -ENODEV;

		}



		trng = list_first_entry(&trng_devices.list,

					struct hisi_trng, list);

		trng->ctx_num++;

		ctx->trng = trng;

		mutex_unlock(&trng_devices.lock);

	}



	return ret;

}
@@ -177,7 +213,12 @@ static void hisi_trng_exit(struct crypto_tfm *tfm) 
	struct hisi_trng_ctx *ctx = crypto_tfm_ctx(tfm);



	mutex_lock(&trng_devices.lock);

	if (!ctx->drbg)

		ctx->trng->is_used = false;

	else

		crypto_free_rng(ctx->drbg);



	ctx->trng->ctx_num--;

	mutex_unlock(&trng_devices.lock);

}
@@ -239,7 +280,7 @@ static int hisi_trng_del_from_list(struct hisi_trng *trng) 
	int ret = -EBUSY;



	mutex_lock(&trng_devices.lock);

	if (!trng->is_used) {

	if (!trng->ctx_num) {

		list_del(&trng->list);

		ret = 0;

	}
@@ -264,6 +305,7 @@ static int hisi_trng_probe(struct platform_device *pdev) 
		return PTR_ERR(trng->base);



	trng->is_used = false;

	trng->ctx_num = 0;

	trng->ver = readl(trng->base + HISI_TRNG_VERSION);

	if (!trng_devices.is_init) {

		INIT_LIST_HEAD(&trng_devices.list);
@@ -310,7 +352,7 @@ static void hisi_trng_remove(struct platform_device *pdev) 


	/* Wait until the task is finished */

	while (hisi_trng_del_from_list(trng))

		;

		msleep(WAIT_PERIOD);



	if (trng->ver != HISI_TRNG_VER_V1 &&

	    atomic_dec_return(&trng_active_devs) == 0)