Expose SEC4 DRNG IP block using crypto RNG API so it could be used both by kernel and userspace code. Signed-off-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx> Cc: Chris Healy <cphealy@xxxxxxxxx> Cc: Lucas Stach <l.stach@xxxxxxxxxxxxxx> Cc: Horia Geantă <horia.geanta@xxxxxxx> Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Cc: Iuliana Prodan <iuliana.prodan@xxxxxxx> Cc: linux-imx@xxxxxxx Cc: linux-crypto@xxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx --- drivers/crypto/caam/Kconfig | 8 ++ drivers/crypto/caam/Makefile | 1 + drivers/crypto/caam/drng.c | 175 +++++++++++++++++++++++++++++++++++ drivers/crypto/caam/intern.h | 13 +++ drivers/crypto/caam/jr.c | 1 + 5 files changed, 198 insertions(+) create mode 100644 drivers/crypto/caam/drng.c diff --git a/drivers/crypto/caam/Kconfig b/drivers/crypto/caam/Kconfig index 22116a8e2ff3..11a8f9c02448 100644 --- a/drivers/crypto/caam/Kconfig +++ b/drivers/crypto/caam/Kconfig @@ -146,6 +146,14 @@ config CRYPTO_DEV_FSL_CAAM_PKC_API Supported cryptographic primitives: encryption, decryption, signature and verification. +config CRYPTO_DEV_FSL_CAAM_DRNG_API + bool "Register caam device for hwrng API" + default y + select CRYPTO_RNG + help + Selecting this will register the SEC4 DRNG to + the crypto RNG API. + endif # CRYPTO_DEV_FSL_CAAM_JR endif # CRYPTO_DEV_FSL_CAAM diff --git a/drivers/crypto/caam/Makefile b/drivers/crypto/caam/Makefile index 04884fc087f9..02b7ed8823ce 100644 --- a/drivers/crypto/caam/Makefile +++ b/drivers/crypto/caam/Makefile @@ -20,6 +20,7 @@ caam_jr-y := jr.o key_gen.o caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API) += caamalg.o caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API_QI) += caamalg_qi.o caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_AHASH_API) += caamhash.o +caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_DRNG_API) += drng.o caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_PKC_API) += caampkc.o pkc_desc.o caam-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API_QI) += qi.o diff --git a/drivers/crypto/caam/drng.c b/drivers/crypto/caam/drng.c new file mode 100644 index 000000000000..9b2ff2fe7581 --- /dev/null +++ b/drivers/crypto/caam/drng.c @@ -0,0 +1,175 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Driver to expose SEC4 DRNG via crypto RNG API + * + * Copyright 2019 Zodiac Inflight Innovations + * + * Based on CAAM SEC4 hw_random driver + * + * Copyright 2011 Freescale Semiconductor, Inc. + * Copyright 2018-2019 NXP + * + * Based on caamalg.c crypto API driver. + * + */ + +#include <linux/completion.h> +#include <linux/atomic.h> + +#include <crypto/internal/rng.h> + +#include "compat.h" + +#include "regs.h" +#include "intern.h" +#include "desc_constr.h" +#include "jr.h" +#include "error.h" + +#define CAAM_DRNG_MAX_FIFO_STORE_SIZE ((unsigned int)U16_MAX) + +/* rng per-device context */ +struct caam_drng_ctx { + struct device *jrdev; + struct completion done; +}; + +static void rng_done(struct device *jrdev, u32 *desc, u32 err, void *context) +{ + struct caam_drng_ctx *ctx = context; + + if (err) + caam_jr_strstatus(jrdev, err); + + complete(&ctx->done); +} + +static int caam_drng_generate(struct crypto_rng *tfm, + const u8 *src, unsigned int slen, + u8 *dst, unsigned int dlen) +{ + struct caam_drng_ctx *ctx = crypto_rng_ctx(tfm); + struct device *jrdev = ctx->jrdev; + unsigned int residue = dlen; + dma_addr_t dst_dma, cur_dma; + u32 *desc; + int ret; + + desc = kzalloc(5 * CAAM_CMD_SZ + CAAM_PTR_SZ_MAX, + GFP_KERNEL | GFP_DMA); + if (!desc) + return -ENOMEM; + + cur_dma = dst_dma = dma_map_single(jrdev, dst, dlen, DMA_FROM_DEVICE); + if (dma_mapping_error(jrdev, dst_dma)) { + dev_err(jrdev, "unable to map destination memory\n"); + ret = -ENOMEM; + goto free_mem; + } + + do { + const unsigned int chunk = min(residue, + CAAM_DRNG_MAX_FIFO_STORE_SIZE); + + init_job_desc(desc, 0); /* 1 word */ + /* Generate random bytes */ + append_operation(desc, OP_ALG_ALGSEL_RNG | OP_TYPE_CLASS1_ALG | + OP_ALG_PR_ON); /* 1 word */ + /* Store bytes */ + append_seq_out_ptr_intlen(desc, cur_dma, chunk, 0); + append_seq_fifo_store(desc, chunk, FIFOST_TYPE_RNGSTORE); + + print_hex_dump_debug("rng job desc@: ", DUMP_PREFIX_ADDRESS, + 16, 4, desc, desc_bytes(desc), 1); + + init_completion(&ctx->done); + ret = caam_jr_enqueue(jrdev, desc, rng_done, ctx); + if (ret) + break; + + wait_for_completion(&ctx->done); + + cur_dma += chunk; + residue -= chunk; + } while (residue); + + dma_unmap_single(jrdev, dst_dma, dlen, DMA_FROM_DEVICE); +free_mem: + kfree(desc); + return ret; +} + +static int caam_drng_init(struct crypto_tfm *tfm) +{ + struct caam_drng_ctx *ctx = crypto_tfm_ctx(tfm); + int ret; + + ctx->jrdev = caam_jr_alloc(); + ret = PTR_ERR_OR_ZERO(ctx->jrdev); + if (ret) { + pr_err("Job Ring Device allocation for transform failed\n"); + return ret; + } + + return 0; +} + +static void caam_drng_exit(struct crypto_tfm *tfm) +{ + struct caam_drng_ctx *ctx = crypto_tfm_ctx(tfm); + + caam_jr_free(ctx->jrdev); +} + +static int caam_drng_seed(struct crypto_rng *tfm, + const u8 *seed, unsigned int slen) +{ + return 0; +} + +static struct rng_alg caam_drng_alg = { + .generate = caam_drng_generate, + .seed = caam_drng_seed, + .seedsize = 0, + .base = { + .cra_name = "stdrng", + .cra_driver_name = "drng-caam", + .cra_priority = 300, + .cra_ctxsize = sizeof(struct caam_drng_ctx), + .cra_module = THIS_MODULE, + .cra_init = caam_drng_init, + .cra_exit = caam_drng_exit, + }, +}; + +static void caam_drng_unregister(void *data) +{ + crypto_unregister_rng(&caam_drng_alg); +} + +int caam_drng_register(struct device *ctrldev) +{ + struct caam_drv_private *priv = dev_get_drvdata(ctrldev); + + if (caam_has_rng(priv)) { + int ret; + + ret = crypto_register_rng(&caam_drng_alg); + if (ret) { + dev_err(ctrldev, + "couldn't register rng crypto alg: %d\n", + ret); + return ret; + } + + ret = devm_add_action_or_reset(ctrldev, caam_drng_unregister, + NULL); + if (ret) + return ret; + + dev_info(ctrldev, + "registering %s\n", caam_drng_alg.base.cra_name); + } + + return 0; +} diff --git a/drivers/crypto/caam/intern.h b/drivers/crypto/caam/intern.h index 54bb04aa86bd..0c81eefd13a9 100644 --- a/drivers/crypto/caam/intern.h +++ b/drivers/crypto/caam/intern.h @@ -185,6 +185,19 @@ static inline int caam_trng_register(struct device *dev) #endif /* CONFIG_CRYPTO_DEV_FSL_CAAM_RNG_API */ +#ifdef CONFIG_CRYPTO_DEV_FSL_CAAM_DRNG_API + +int caam_drng_register(struct device *dev); + +#else + +static inline int caam_drng_register(struct device *dev) +{ + return 0; +} + +#endif /* CONFIG_CRYPTO_DEV_FSL_CAAM_DRNG_API */ + #ifdef CONFIG_CAAM_QI int caam_qi_algapi_init(struct device *dev); diff --git a/drivers/crypto/caam/jr.c b/drivers/crypto/caam/jr.c index c745b7044fe6..e68ba0606e3f 100644 --- a/drivers/crypto/caam/jr.c +++ b/drivers/crypto/caam/jr.c @@ -38,6 +38,7 @@ static void register_algs(struct device *dev) caam_algapi_hash_init(dev); caam_pkc_init(dev); caam_qi_algapi_init(dev); + caam_drng_register(dev); algs_unlock: mutex_unlock(&algs_lock); -- 2.21.0