From: Weili Qian qianweili@huawei.com
mainline inclusion from mainline-v5.11-rc1 commit e4d9d10ef4be0366316b3114593e4becf5b98a49 category: feature bugzilla: 173981 CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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This patch adds support for pseudo random number generator(PRNG) in Crypto subsystem.
Signed-off-by: Weili Qian qianweili@huawei.com Reviewed-by: Zaibo Xu xuzaibo@huawei.com Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Mingqiang Ling lingmingqiang@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- drivers/crypto/hisilicon/Kconfig | 1 + drivers/crypto/hisilicon/trng/trng.c | 241 ++++++++++++++++++++++++++- 2 files changed, 239 insertions(+), 3 deletions(-)
diff --git a/drivers/crypto/hisilicon/Kconfig b/drivers/crypto/hisilicon/Kconfig index 2cd3298920fa..843192666dc3 100644 --- a/drivers/crypto/hisilicon/Kconfig +++ b/drivers/crypto/hisilicon/Kconfig @@ -76,5 +76,6 @@ config CRYPTO_DEV_HISI_TRNG tristate "Support for HISI TRNG Driver" depends on ARM64 && ACPI select HW_RANDOM + select CRYPTO_RNG help Support for HiSilicon TRNG Driver. diff --git a/drivers/crypto/hisilicon/trng/trng.c b/drivers/crypto/hisilicon/trng/trng.c index 6a65b8232ce0..a5033cf09e2b 100644 --- a/drivers/crypto/hisilicon/trng/trng.c +++ b/drivers/crypto/hisilicon/trng/trng.c @@ -2,26 +2,181 @@ /* Copyright (c) 2019 HiSilicon Limited. */
#include <linux/acpi.h> +#include <linux/crypto.h> #include <linux/err.h> #include <linux/hw_random.h> #include <linux/io.h> #include <linux/iopoll.h> #include <linux/kernel.h> +#include <linux/list.h> #include <linux/module.h> +#include <linux/mutex.h> #include <linux/platform_device.h> #include <linux/random.h> +#include <crypto/internal/rng.h>
#define HISI_TRNG_REG 0x00F0 #define HISI_TRNG_BYTES 4 #define HISI_TRNG_QUALITY 512 #define SLEEP_US 10 #define TIMEOUT_US 10000 +#define SW_DRBG_NUM_SHIFT 2 +#define SW_DRBG_KEY_BASE 0x082C +#define SW_DRBG_SEED(n) (SW_DRBG_KEY_BASE - ((n) << SW_DRBG_NUM_SHIFT)) +#define SW_DRBG_SEED_REGS_NUM 12 +#define SW_DRBG_SEED_SIZE 48 +#define SW_DRBG_BLOCKS 0x0830 +#define SW_DRBG_INIT 0x0834 +#define SW_DRBG_GEN 0x083c +#define SW_DRBG_STATUS 0x0840 +#define SW_DRBG_BLOCKS_NUM 4095 +#define SW_DRBG_DATA_BASE 0x0850 +#define SW_DRBG_DATA_NUM 4 +#define SW_DRBG_DATA(n) (SW_DRBG_DATA_BASE - ((n) << SW_DRBG_NUM_SHIFT)) +#define SW_DRBG_BYTES 16 +#define SW_DRBG_ENABLE_SHIFT 12 +#define SEED_SHIFT_24 24 +#define SEED_SHIFT_16 16 +#define SEED_SHIFT_8 8 + +struct hisi_trng_list { + struct mutex lock; + struct list_head list; + bool is_init; +};
struct hisi_trng { void __iomem *base; + struct hisi_trng_list *trng_list; + struct list_head list; struct hwrng rng; + bool is_used; + struct mutex mutex; +}; + +struct hisi_trng_ctx { + struct hisi_trng *trng; };
+static atomic_t trng_active_devs; +static struct hisi_trng_list trng_devices; + +static void hisi_trng_set_seed(struct hisi_trng *trng, const u8 *seed) +{ + u32 val, seed_reg, i; + + for (i = 0; i < SW_DRBG_SEED_SIZE; + i += SW_DRBG_SEED_SIZE / SW_DRBG_SEED_REGS_NUM) { + val = seed[i] << SEED_SHIFT_24; + val |= seed[i + 1UL] << SEED_SHIFT_16; + val |= seed[i + 2UL] << SEED_SHIFT_8; + val |= seed[i + 3UL]; + + seed_reg = (i >> SW_DRBG_NUM_SHIFT) % SW_DRBG_SEED_REGS_NUM; + writel(val, trng->base + SW_DRBG_SEED(seed_reg)); + } +} + +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 hisi_trng *trng = ctx->trng; + u32 val = 0; + int ret = 0; + + if (slen < SW_DRBG_SEED_SIZE) { + pr_err("slen(%u) is not matched with trng(%d)\n", slen, + SW_DRBG_SEED_SIZE); + return -EINVAL; + } + + writel(0x0, trng->base + SW_DRBG_BLOCKS); + hisi_trng_set_seed(trng, seed); + + writel(SW_DRBG_BLOCKS_NUM | (0x1 << SW_DRBG_ENABLE_SHIFT), + trng->base + SW_DRBG_BLOCKS); + writel(0x1, trng->base + SW_DRBG_INIT); + + ret = readl_relaxed_poll_timeout(trng->base + SW_DRBG_STATUS, + val, val & BIT(0), SLEEP_US, TIMEOUT_US); + if (ret) + pr_err("fail to init trng(%d)\n", ret); + + return ret; +} + +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 hisi_trng *trng = ctx->trng; + u32 data[SW_DRBG_DATA_NUM]; + u32 currsize = 0; + u32 val = 0; + int ret; + u32 i; + + if (dlen > SW_DRBG_BLOCKS_NUM * SW_DRBG_BYTES || dlen == 0) { + pr_err("dlen(%d) exceeds limit(%d)!\n", dlen, + SW_DRBG_BLOCKS_NUM * SW_DRBG_BYTES); + return -EINVAL; + } + + do { + ret = readl_relaxed_poll_timeout(trng->base + SW_DRBG_STATUS, + val, val & BIT(1), SLEEP_US, TIMEOUT_US); + if (ret) { + pr_err("fail to generate random number(%d)!\n", ret); + break; + } + + for (i = 0; i < SW_DRBG_DATA_NUM; i++) + data[i] = readl(trng->base + SW_DRBG_DATA(i)); + + if (dlen - currsize >= SW_DRBG_BYTES) { + memcpy(dstn + currsize, data, SW_DRBG_BYTES); + currsize += SW_DRBG_BYTES; + } else { + memcpy(dstn + currsize, data, dlen - currsize); + currsize = dlen; + } + + writel(0x1, trng->base + SW_DRBG_GEN); + } while (currsize < dlen); + + return ret; +} + +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; + + mutex_lock(&trng_devices.lock); + list_for_each_entry(trng, &trng_devices.list, list) { + if (!trng->is_used) { + trng->is_used = true; + ctx->trng = trng; + ret = 0; + break; + } + } + mutex_unlock(&trng_devices.lock); + + return ret; +} + +static void hisi_trng_exit(struct crypto_tfm *tfm) +{ + struct hisi_trng_ctx *ctx = crypto_tfm_ctx(tfm); + + mutex_lock(&trng_devices.lock); + ctx->trng->is_used = false; + mutex_unlock(&trng_devices.lock); +} + static int hisi_trng_read(struct hwrng *rng, void *buf, size_t max, bool wait) { struct hisi_trng *trng; @@ -53,6 +208,42 @@ static int hisi_trng_read(struct hwrng *rng, void *buf, size_t max, bool wait) return currsize; }
+static struct rng_alg hisi_trng_alg = { + .generate = hisi_trng_generate, + .seed = hisi_trng_seed, + .seedsize = SW_DRBG_SEED_SIZE, + .base = { + .cra_name = "stdrng", + .cra_driver_name = "hisi_stdrng", + .cra_priority = 300, + .cra_ctxsize = sizeof(struct hisi_trng_ctx), + .cra_module = THIS_MODULE, + .cra_init = hisi_trng_init, + .cra_exit = hisi_trng_exit, + }, +}; + +static void hisi_trng_add_to_list(struct hisi_trng *trng) +{ + mutex_lock(&trng_devices.lock); + list_add_tail(&trng->list, &trng_devices.list); + mutex_unlock(&trng_devices.lock); +} + +static int hisi_trng_del_from_list(struct hisi_trng *trng) +{ + int ret = -EBUSY; + + mutex_lock(&trng_devices.lock); + if (!trng->is_used) { + list_del(&trng->list); + ret = 0; + } + mutex_unlock(&trng_devices.lock); + + return ret; +} + static int hisi_trng_probe(struct platform_device *pdev) { struct hisi_trng *trng; @@ -62,19 +253,62 @@ static int hisi_trng_probe(struct platform_device *pdev) if (!trng) return -ENOMEM;
+ platform_set_drvdata(pdev, trng); + trng->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(trng->base)) return PTR_ERR(trng->base);
+ trng->is_used = false; + if (!trng_devices.is_init) { + INIT_LIST_HEAD(&trng_devices.list); + mutex_init(&trng_devices.lock); + trng_devices.is_init = true; + } + + hisi_trng_add_to_list(trng); + if (atomic_add_return(1, &trng_active_devs) == 1) { + ret = crypto_register_rng(&hisi_trng_alg); + if (ret) { + dev_err(&pdev->dev, + "failed to register crypto(%d)\n", ret); + atomic_sub_return(1, &trng_active_devs); + goto err_remove_from_list; + } + } + trng->rng.name = pdev->name; trng->rng.read = hisi_trng_read; trng->rng.quality = HISI_TRNG_QUALITY; - ret = devm_hwrng_register(&pdev->dev, &trng->rng); - if (ret) - dev_err(&pdev->dev, "failed to register hwrng!\n"); + if (ret) { + dev_err(&pdev->dev, "failed to register hwrng: %d!\n", ret); + goto err_crypto_unregister; + }
return ret; + +err_crypto_unregister: + if (atomic_sub_return(1, &trng_active_devs) == 0) + crypto_unregister_rng(&hisi_trng_alg); + +err_remove_from_list: + hisi_trng_del_from_list(trng); + return ret; +} + +static int hisi_trng_remove(struct platform_device *pdev) +{ + struct hisi_trng *trng = platform_get_drvdata(pdev); + + /* Wait until the task is finished */ + while (hisi_trng_del_from_list(trng)) + ; + + if (atomic_sub_return(1, &trng_active_devs) == 0) + crypto_unregister_rng(&hisi_trng_alg); + + return 0; }
static const struct acpi_device_id hisi_trng_acpi_match[] = { @@ -85,6 +319,7 @@ MODULE_DEVICE_TABLE(acpi, hisi_trng_acpi_match);
static struct platform_driver hisi_trng_driver = { .probe = hisi_trng_probe, + .remove = hisi_trng_remove, .driver = { .name = "hisi-trng-v2", .acpi_match_table = ACPI_PTR(hisi_trng_acpi_match),