diff options
author | Victoria Milhoan (b42089) <vicki.milhoan@freescale.com> | 2023-06-12 11:28:42 +0300 |
---|---|---|
committer | Herbert Xu <herbert@gondor.apana.org.au> | 2023-06-23 11:15:36 +0300 |
commit | 2be0d806e25e7b068113187f9245575914daf0dc (patch) | |
tree | 16cc5b2ac0b1f24b5a482cced4f609e8132dd157 /drivers/crypto | |
parent | ef492d080302913e85122a2d92efa2ca174930f8 (diff) | |
download | linux-2be0d806e25e7b068113187f9245575914daf0dc.tar.xz |
crypto: caam - add a test for the RNG
CAAM includes a Random Number Generator. This change adds
a kernel configuration option to test the RNG's capabilities via the
hw_random framework.
Signed-off-by: Victoria Milhoan <vicki.milhoan@freescale.com>
Signed-off-by: Dan Douglass <dan.douglass@nxp.com>
Signed-off-by: Vipul Kumar <vipul_kumar@mentor.com>
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Meenakshi Aggarwal <meenakshi.aggarwal@nxp.com>
Reviewed-by: Gaurav Jain <gaurav.jain@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/crypto')
-rw-r--r-- | drivers/crypto/caam/Kconfig | 9 | ||||
-rw-r--r-- | drivers/crypto/caam/caamrng.c | 48 |
2 files changed, 57 insertions, 0 deletions
diff --git a/drivers/crypto/caam/Kconfig b/drivers/crypto/caam/Kconfig index ec6a9e6ad4d2..c631f99e415f 100644 --- a/drivers/crypto/caam/Kconfig +++ b/drivers/crypto/caam/Kconfig @@ -162,6 +162,15 @@ config CRYPTO_DEV_FSL_CAAM_PRNG_API config CRYPTO_DEV_FSL_CAAM_BLOB_GEN bool +config CRYPTO_DEV_FSL_CAAM_RNG_TEST + bool "Test caam rng" + select CRYPTO_DEV_FSL_CAAM_RNG_API + help + Selecting this will enable a self-test to run for the + caam RNG. + This test is several minutes long and executes + just before the RNG is registered with the hw_random API. + endif # CRYPTO_DEV_FSL_CAAM_JR endif # CRYPTO_DEV_FSL_CAAM diff --git a/drivers/crypto/caam/caamrng.c b/drivers/crypto/caam/caamrng.c index 50eb55da45c2..b3d14a7f4dd1 100644 --- a/drivers/crypto/caam/caamrng.c +++ b/drivers/crypto/caam/caamrng.c @@ -172,6 +172,50 @@ static void caam_cleanup(struct hwrng *rng) kfifo_free(&ctx->fifo); } +#ifdef CONFIG_CRYPTO_DEV_FSL_CAAM_RNG_TEST +static inline void test_len(struct hwrng *rng, size_t len, bool wait) +{ + u8 *buf; + int read_len; + struct caam_rng_ctx *ctx = to_caam_rng_ctx(rng); + struct device *dev = ctx->ctrldev; + + buf = kcalloc(CAAM_RNG_MAX_FIFO_STORE_SIZE, sizeof(u8), GFP_KERNEL); + + while (len > 0) { + read_len = rng->read(rng, buf, len, wait); + + if (read_len < 0 || (read_len == 0 && wait)) { + dev_err(dev, "RNG Read FAILED received %d bytes\n", + read_len); + kfree(buf); + return; + } + + print_hex_dump_debug("random bytes@: ", + DUMP_PREFIX_ADDRESS, 16, 4, + buf, read_len, 1); + + len = len - read_len; + } + + kfree(buf); +} + +static inline void test_mode_once(struct hwrng *rng, bool wait) +{ + test_len(rng, 32, wait); + test_len(rng, 64, wait); + test_len(rng, 128, wait); +} + +static void self_test(struct hwrng *rng) +{ + pr_info("Executing RNG SELF-TEST with wait\n"); + test_mode_once(rng, true); +} +#endif + static int caam_init(struct hwrng *rng) { struct caam_rng_ctx *ctx = to_caam_rng_ctx(rng); @@ -258,6 +302,10 @@ int caam_rng_init(struct device *ctrldev) return ret; } +#ifdef CONFIG_CRYPTO_DEV_FSL_CAAM_RNG_TEST + self_test(&ctx->rng); +#endif + devres_close_group(ctrldev, caam_rng_init); return 0; } |