From d072bfa4885354fff86aa1fb1dbc4f1533c9e0bf Mon Sep 17 00:00:00 2001 From: Christian Lamparter Date: Sun, 23 Dec 2018 02:16:13 +0100 Subject: [PATCH] crypto: crypto4xx - add prng crypto support This patch adds support for crypto4xx's ANSI X9.17 Annex C compliant pseudo random number generator which provides a pseudo random source for the purpose of generating Initialization Vectors (IV's) for AES algorithms to the Packet Engine and other pseudo random number requirements. Signed-off-by: Christian Lamparter Signed-off-by: Herbert Xu --- drivers/crypto/amcc/crypto4xx_core.c | 87 +++++++++++++++++++++++++ drivers/crypto/amcc/crypto4xx_core.h | 4 ++ drivers/crypto/amcc/crypto4xx_reg_def.h | 1 + 3 files changed, 92 insertions(+) diff --git a/drivers/crypto/amcc/crypto4xx_core.c b/drivers/crypto/amcc/crypto4xx_core.c index 63cb6956c948..f869e8cc4e0b 100644 --- a/drivers/crypto/amcc/crypto4xx_core.c +++ b/drivers/crypto/amcc/crypto4xx_core.c @@ -40,9 +40,11 @@ #include #include #include +#include #include #include #include +#include #include #include "crypto4xx_reg_def.h" #include "crypto4xx_core.h" @@ -1035,6 +1037,10 @@ static int crypto4xx_register_alg(struct crypto4xx_device *sec_dev, rc = crypto_register_ahash(&alg->alg.u.hash); break; + case CRYPTO_ALG_TYPE_RNG: + rc = crypto_register_rng(&alg->alg.u.rng); + break; + default: rc = crypto_register_skcipher(&alg->alg.u.cipher); break; @@ -1064,6 +1070,10 @@ static void crypto4xx_unregister_alg(struct crypto4xx_device *sec_dev) crypto_unregister_aead(&alg->alg.u.aead); break; + case CRYPTO_ALG_TYPE_RNG: + crypto_unregister_rng(&alg->alg.u.rng); + break; + default: crypto_unregister_skcipher(&alg->alg.u.cipher); } @@ -1122,6 +1132,69 @@ static irqreturn_t crypto4xx_ce_interrupt_handler_revb(int irq, void *data) PPC4XX_TMO_ERR_INT); } +static int ppc4xx_prng_data_read(struct crypto4xx_device *dev, + u8 *data, unsigned int max) +{ + unsigned int i, curr = 0; + u32 val[2]; + + do { + /* trigger PRN generation */ + writel(PPC4XX_PRNG_CTRL_AUTO_EN, + dev->ce_base + CRYPTO4XX_PRNG_CTRL); + + for (i = 0; i < 1024; i++) { + /* usually 19 iterations are enough */ + if ((readl(dev->ce_base + CRYPTO4XX_PRNG_STAT) & + CRYPTO4XX_PRNG_STAT_BUSY)) + continue; + + val[0] = readl_be(dev->ce_base + CRYPTO4XX_PRNG_RES_0); + val[1] = readl_be(dev->ce_base + CRYPTO4XX_PRNG_RES_1); + break; + } + if (i == 1024) + return -ETIMEDOUT; + + if ((max - curr) >= 8) { + memcpy(data, &val, 8); + data += 8; + curr += 8; + } else { + /* copy only remaining bytes */ + memcpy(data, &val, max - curr); + break; + } + } while (curr < max); + + return curr; +} + +static int crypto4xx_prng_generate(struct crypto_rng *tfm, + const u8 *src, unsigned int slen, + u8 *dstn, unsigned int dlen) +{ + struct rng_alg *alg = crypto_rng_alg(tfm); + struct crypto4xx_alg *amcc_alg; + struct crypto4xx_device *dev; + int ret; + + amcc_alg = container_of(alg, struct crypto4xx_alg, alg.u.rng); + dev = amcc_alg->dev; + + mutex_lock(&dev->core_dev->rng_lock); + ret = ppc4xx_prng_data_read(dev, dstn, dlen); + mutex_unlock(&dev->core_dev->rng_lock); + return ret; +} + + +static int crypto4xx_prng_seed(struct crypto_rng *tfm, const u8 *seed, + unsigned int slen) +{ + return 0; +} + /** * Supported Crypto Algorithms */ @@ -1291,6 +1364,18 @@ static struct crypto4xx_alg_common crypto4xx_alg[] = { .cra_module = THIS_MODULE, }, } }, + { .type = CRYPTO_ALG_TYPE_RNG, .u.rng = { + .base = { + .cra_name = "stdrng", + .cra_driver_name = "crypto4xx_rng", + .cra_priority = 300, + .cra_ctxsize = 0, + .cra_module = THIS_MODULE, + }, + .generate = crypto4xx_prng_generate, + .seed = crypto4xx_prng_seed, + .seedsize = 0, + } }, }; /** @@ -1360,6 +1445,7 @@ static int crypto4xx_probe(struct platform_device *ofdev) core_dev->dev->core_dev = core_dev; core_dev->dev->is_revb = is_revb; core_dev->device = dev; + mutex_init(&core_dev->rng_lock); spin_lock_init(&core_dev->lock); INIT_LIST_HEAD(&core_dev->dev->alg_list); ratelimit_default_init(&core_dev->dev->aead_ratelimit); @@ -1439,6 +1525,7 @@ static int crypto4xx_remove(struct platform_device *ofdev) tasklet_kill(&core_dev->tasklet); /* Un-register with Linux CryptoAPI */ crypto4xx_unregister_alg(core_dev->dev); + mutex_destroy(&core_dev->rng_lock); /* Free all allocated memory */ crypto4xx_stop_all(core_dev); diff --git a/drivers/crypto/amcc/crypto4xx_core.h b/drivers/crypto/amcc/crypto4xx_core.h index e2ca56722f07..18df695ca6b1 100644 --- a/drivers/crypto/amcc/crypto4xx_core.h +++ b/drivers/crypto/amcc/crypto4xx_core.h @@ -23,8 +23,10 @@ #define __CRYPTO4XX_CORE_H__ #include +#include #include #include +#include #include #include "crypto4xx_reg_def.h" #include "crypto4xx_sa.h" @@ -119,6 +121,7 @@ struct crypto4xx_core_device { u32 irq; struct tasklet_struct tasklet; spinlock_t lock; + struct mutex rng_lock; }; struct crypto4xx_ctx { @@ -143,6 +146,7 @@ struct crypto4xx_alg_common { struct skcipher_alg cipher; struct ahash_alg hash; struct aead_alg aead; + struct rng_alg rng; } u; }; diff --git a/drivers/crypto/amcc/crypto4xx_reg_def.h b/drivers/crypto/amcc/crypto4xx_reg_def.h index 472331787e04..80c67490bbf6 100644 --- a/drivers/crypto/amcc/crypto4xx_reg_def.h +++ b/drivers/crypto/amcc/crypto4xx_reg_def.h @@ -100,6 +100,7 @@ #define CRYPTO4XX_ENDIAN_CFG 0x000600d8 #define CRYPTO4XX_PRNG_STAT 0x00070000 +#define CRYPTO4XX_PRNG_STAT_BUSY 0x1 #define CRYPTO4XX_PRNG_CTRL 0x00070004 #define CRYPTO4XX_PRNG_SEED_L 0x00070008 #define CRYPTO4XX_PRNG_SEED_H 0x0007000c -- 2.30.2