diff options
author | Corentin Labbe <clabbe@baylibre.com> | 2020-09-18 07:23:00 +0000 |
---|---|---|
committer | Herbert Xu <herbert@gondor.apana.org.au> | 2020-09-25 17:48:16 +1000 |
commit | ac2614d721dea2ff273af19c6c5d508d58a2bb3e (patch) | |
tree | d2b399ca96c390c093b4d33d9fd513e214eabc36 /drivers/crypto/allwinner | |
parent | f1455b18ee182e07a5d9c0fe3e102a33fc5e6f34 (diff) |
crypto: sun8i-ss - Add support for the PRNG
This patch had support for the PRNG present in the SS.
The output was tested with rngtest without any failure.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/crypto/allwinner')
-rw-r--r-- | drivers/crypto/allwinner/Kconfig | 8 | ||||
-rw-r--r-- | drivers/crypto/allwinner/sun8i-ss/Makefile | 1 | ||||
-rw-r--r-- | drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c | 39 | ||||
-rw-r--r-- | drivers/crypto/allwinner/sun8i-ss/sun8i-ss-prng.c | 173 | ||||
-rw-r--r-- | drivers/crypto/allwinner/sun8i-ss/sun8i-ss.h | 25 |
5 files changed, 246 insertions, 0 deletions
diff --git a/drivers/crypto/allwinner/Kconfig b/drivers/crypto/allwinner/Kconfig index 12e7c6a85a02..e7740d6f1b75 100644 --- a/drivers/crypto/allwinner/Kconfig +++ b/drivers/crypto/allwinner/Kconfig @@ -85,3 +85,11 @@ config CRYPTO_DEV_SUN8I_SS_DEBUG Say y to enable sun8i-ss debug stats. This will create /sys/kernel/debug/sun8i-ss/stats for displaying the number of requests per flow and per algorithm. + +config CRYPTO_DEV_SUN8I_SS_PRNG + bool "Support for Allwinner Security System PRNG" + depends on CRYPTO_DEV_SUN8I_SS + select CRYPTO_RNG + help + Select this option if you want to provide kernel-side support for + the Pseudo-Random Number Generator found in the Security System. diff --git a/drivers/crypto/allwinner/sun8i-ss/Makefile b/drivers/crypto/allwinner/sun8i-ss/Makefile index add7b0543fd5..49f2f912c816 100644 --- a/drivers/crypto/allwinner/sun8i-ss/Makefile +++ b/drivers/crypto/allwinner/sun8i-ss/Makefile @@ -1,2 +1,3 @@ obj-$(CONFIG_CRYPTO_DEV_SUN8I_SS) += sun8i-ss.o sun8i-ss-y += sun8i-ss-core.o sun8i-ss-cipher.o +sun8i-ss-$(CONFIG_CRYPTO_DEV_SUN8I_SS_PRNG) += sun8i-ss-prng.o diff --git a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c index adcae3ae2b2e..86de39e8e91c 100644 --- a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c +++ b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c @@ -22,6 +22,7 @@ #include <linux/platform_device.h> #include <linux/pm_runtime.h> #include <linux/reset.h> +#include <crypto/internal/rng.h> #include <crypto/internal/skcipher.h> #include "sun8i-ss.h" @@ -264,6 +265,25 @@ static struct sun8i_ss_alg_template ss_algs[] = { .decrypt = sun8i_ss_skdecrypt, } }, +#ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_PRNG +{ + .type = CRYPTO_ALG_TYPE_RNG, + .alg.rng = { + .base = { + .cra_name = "stdrng", + .cra_driver_name = "sun8i-ss-prng", + .cra_priority = 300, + .cra_ctxsize = sizeof(struct sun8i_ss_rng_tfm_ctx), + .cra_module = THIS_MODULE, + .cra_init = sun8i_ss_prng_init, + .cra_exit = sun8i_ss_prng_exit, + }, + .generate = sun8i_ss_prng_generate, + .seed = sun8i_ss_prng_seed, + .seedsize = PRNG_SEED_SIZE, + } +}, +#endif }; #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG @@ -285,6 +305,12 @@ static int sun8i_ss_debugfs_show(struct seq_file *seq, void *v) ss_algs[i].alg.skcipher.base.cra_name, ss_algs[i].stat_req, ss_algs[i].stat_fb); break; + case CRYPTO_ALG_TYPE_RNG: + seq_printf(seq, "%s %s %lu %lu\n", + ss_algs[i].alg.rng.base.cra_driver_name, + ss_algs[i].alg.rng.base.cra_name, + ss_algs[i].stat_req, ss_algs[i].stat_bytes); + break; } } return 0; @@ -437,6 +463,14 @@ static int sun8i_ss_register_algs(struct sun8i_ss_dev *ss) return err; } break; + case CRYPTO_ALG_TYPE_RNG: + err = crypto_register_rng(&ss_algs[i].alg.rng); + if (err) { + dev_err(ss->dev, "Fail to register %s\n", + ss_algs[i].alg.rng.base.cra_name); + ss_algs[i].ss = NULL; + } + break; default: ss_algs[i].ss = NULL; dev_err(ss->dev, "ERROR: tried to register an unknown algo\n"); @@ -458,6 +492,11 @@ static void sun8i_ss_unregister_algs(struct sun8i_ss_dev *ss) ss_algs[i].alg.skcipher.base.cra_name); crypto_unregister_skcipher(&ss_algs[i].alg.skcipher); break; + case CRYPTO_ALG_TYPE_RNG: + dev_info(ss->dev, "Unregister %d %s\n", i, + ss_algs[i].alg.rng.base.cra_name); + crypto_unregister_rng(&ss_algs[i].alg.rng); + break; } } } diff --git a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-prng.c b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-prng.c new file mode 100644 index 000000000000..08a1473b2145 --- /dev/null +++ b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-prng.c @@ -0,0 +1,173 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * sun8i-ss-prng.c - hardware cryptographic offloader for + * Allwinner A80/A83T SoC + * + * Copyright (C) 2015-2020 Corentin Labbe <clabbe@baylibre.com> + * + * This file handle the PRNG found in the SS + * + * You could find a link for the datasheet in Documentation/arm/sunxi.rst + */ +#include "sun8i-ss.h" +#include <linux/dma-mapping.h> +#include <linux/pm_runtime.h> +#include <crypto/internal/rng.h> + +int sun8i_ss_prng_seed(struct crypto_rng *tfm, const u8 *seed, + unsigned int slen) +{ + struct sun8i_ss_rng_tfm_ctx *ctx = crypto_rng_ctx(tfm); + + if (ctx->seed && ctx->slen != slen) { + memzero_explicit(ctx->seed, ctx->slen); + kfree(ctx->seed); + ctx->slen = 0; + ctx->seed = NULL; + } + if (!ctx->seed) + ctx->seed = kmalloc(slen, GFP_KERNEL | GFP_DMA); + if (!ctx->seed) + return -ENOMEM; + + memcpy(ctx->seed, seed, slen); + ctx->slen = slen; + + return 0; +} + +int sun8i_ss_prng_init(struct crypto_tfm *tfm) +{ + struct sun8i_ss_rng_tfm_ctx *ctx = crypto_tfm_ctx(tfm); + + memset(ctx, 0, sizeof(struct sun8i_ss_rng_tfm_ctx)); + return 0; +} + +void sun8i_ss_prng_exit(struct crypto_tfm *tfm) +{ + struct sun8i_ss_rng_tfm_ctx *ctx = crypto_tfm_ctx(tfm); + + memzero_explicit(ctx->seed, ctx->slen); + kfree(ctx->seed); + ctx->seed = NULL; + ctx->slen = 0; +} + +int sun8i_ss_prng_generate(struct crypto_rng *tfm, const u8 *src, + unsigned int slen, u8 *dst, unsigned int dlen) +{ + struct sun8i_ss_rng_tfm_ctx *ctx = crypto_rng_ctx(tfm); + struct rng_alg *alg = crypto_rng_alg(tfm); + struct sun8i_ss_alg_template *algt; + struct sun8i_ss_dev *ss; + dma_addr_t dma_iv, dma_dst; + unsigned int todo; + int err = 0; + int flow; + void *d; + u32 v; + + algt = container_of(alg, struct sun8i_ss_alg_template, alg.rng); + ss = algt->ss; + + if (ctx->slen == 0) { + dev_err(ss->dev, "The PRNG is not seeded\n"); + return -EINVAL; + } + + /* The SS does not give an updated seed, so we need to get a new one. + * So we will ask for an extra PRNG_SEED_SIZE data. + * We want dlen + seedsize rounded up to a multiple of PRNG_DATA_SIZE + */ + todo = dlen + PRNG_SEED_SIZE + PRNG_DATA_SIZE; + todo -= todo % PRNG_DATA_SIZE; + + d = kzalloc(todo, GFP_KERNEL | GFP_DMA); + if (!d) + return -ENOMEM; + + flow = sun8i_ss_get_engine_number(ss); + +#ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG + algt->stat_req++; + algt->stat_bytes += todo; +#endif + + v = SS_ALG_PRNG | SS_PRNG_CONTINUE | SS_START; + if (flow) + v |= SS_FLOW1; + else + v |= SS_FLOW0; + + dma_iv = dma_map_single(ss->dev, ctx->seed, ctx->slen, DMA_TO_DEVICE); + if (dma_mapping_error(ss->dev, dma_iv)) { + dev_err(ss->dev, "Cannot DMA MAP IV\n"); + return -EFAULT; + } + + dma_dst = dma_map_single(ss->dev, d, todo, DMA_FROM_DEVICE); + if (dma_mapping_error(ss->dev, dma_dst)) { + dev_err(ss->dev, "Cannot DMA MAP DST\n"); + err = -EFAULT; + goto err_iv; + } + + err = pm_runtime_get_sync(ss->dev); + if (err < 0) { + pm_runtime_put_noidle(ss->dev); + goto err_pm; + } + err = 0; + + mutex_lock(&ss->mlock); + writel(dma_iv, ss->base + SS_IV_ADR_REG); + /* the PRNG act badly (failing rngtest) without SS_KEY_ADR_REG set */ + writel(dma_iv, ss->base + SS_KEY_ADR_REG); + writel(dma_dst, ss->base + SS_DST_ADR_REG); + writel(todo / 4, ss->base + SS_LEN_ADR_REG); + + reinit_completion(&ss->flows[flow].complete); + ss->flows[flow].status = 0; + /* Be sure all data is written before enabling the task */ + wmb(); + + writel(v, ss->base + SS_CTL_REG); + + wait_for_completion_interruptible_timeout(&ss->flows[flow].complete, + msecs_to_jiffies(todo)); + if (ss->flows[flow].status == 0) { + dev_err(ss->dev, "DMA timeout for PRNG (size=%u)\n", todo); + err = -EFAULT; + } + /* Since cipher and hash use the linux/cryptoengine and that we have + * a cryptoengine per flow, we are sure that they will issue only one + * request per flow. + * Since the cryptoengine wait for completion before submitting a new + * one, the mlock could be left just after the final writel. + * But cryptoengine cannot handle crypto_rng, so we need to be sure + * nothing will use our flow. + * The easiest way is to grab mlock until the hardware end our requests. + * We could have used a per flow lock, but this would increase + * complexity. + * The drawback is that no request could be handled for the other flow. + */ + mutex_unlock(&ss->mlock); + + pm_runtime_put(ss->dev); + +err_pm: + dma_unmap_single(ss->dev, dma_dst, todo, DMA_FROM_DEVICE); +err_iv: + dma_unmap_single(ss->dev, dma_iv, ctx->slen, DMA_TO_DEVICE); + + if (!err) { + memcpy(dst, d, dlen); + /* Update seed */ + memcpy(ctx->seed, d + dlen, ctx->slen); + } + memzero_explicit(d, todo); + kfree(d); + + return err; +} diff --git a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss.h b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss.h index f3ffaea3a59f..adf2ee2395c1 100644 --- a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss.h +++ b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss.h @@ -8,6 +8,7 @@ #include <crypto/aes.h> #include <crypto/des.h> #include <crypto/engine.h> +#include <crypto/rng.h> #include <crypto/skcipher.h> #include <linux/atomic.h> #include <linux/debugfs.h> @@ -21,6 +22,7 @@ #define SS_ALG_AES 0 #define SS_ALG_DES (1 << 2) #define SS_ALG_3DES (2 << 2) +#define SS_ALG_PRNG (4 << 2) #define SS_CTL_REG 0x00 #define SS_INT_CTL_REG 0x04 @@ -52,6 +54,8 @@ #define SS_FLOW0 BIT(30) #define SS_FLOW1 BIT(31) +#define SS_PRNG_CONTINUE BIT(18) + #define MAX_SG 8 #define MAXFLOW 2 @@ -61,6 +65,9 @@ #define SS_DIE_ID_SHIFT 20 #define SS_DIE_ID_MASK 0x07 +#define PRNG_DATA_SIZE (160 / 8) +#define PRNG_SEED_SIZE DIV_ROUND_UP(175, 8) + /* * struct ss_clock - Describe clocks used by sun8i-ss * @name: Name of clock needed by this variant @@ -182,6 +189,16 @@ struct sun8i_cipher_tfm_ctx { }; /* + * struct sun8i_ss_prng_ctx - context for PRNG TFM + * @seed: The seed to use + * @slen: The size of the seed + */ +struct sun8i_ss_rng_tfm_ctx { + void *seed; + unsigned int slen; +}; + +/* * struct sun8i_ss_alg_template - crypto_alg template * @type: the CRYPTO_ALG_TYPE for this template * @ss_algo_id: the SS_ID for this template @@ -191,6 +208,7 @@ struct sun8i_cipher_tfm_ctx { * @alg: one of sub struct must be used * @stat_req: number of request done on this template * @stat_fb: number of request which has fallbacked + * @stat_bytes: total data size done by this template */ struct sun8i_ss_alg_template { u32 type; @@ -199,10 +217,12 @@ struct sun8i_ss_alg_template { struct sun8i_ss_dev *ss; union { struct skcipher_alg skcipher; + struct rng_alg rng; } alg; #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG unsigned long stat_req; unsigned long stat_fb; + unsigned long stat_bytes; #endif }; @@ -220,3 +240,8 @@ int sun8i_ss_skencrypt(struct skcipher_request *areq); int sun8i_ss_get_engine_number(struct sun8i_ss_dev *ss); int sun8i_ss_run_task(struct sun8i_ss_dev *ss, struct sun8i_cipher_req_ctx *rctx, const char *name); +int sun8i_ss_prng_generate(struct crypto_rng *tfm, const u8 *src, + unsigned int slen, u8 *dst, unsigned int dlen); +int sun8i_ss_prng_seed(struct crypto_rng *tfm, const u8 *seed, unsigned int slen); +int sun8i_ss_prng_init(struct crypto_tfm *tfm); +void sun8i_ss_prng_exit(struct crypto_tfm *tfm); |