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 <chunkeey@xxxxxxxxx>
---
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 6eaec9ba0f68..59ee52e8e258 100644
--- a/drivers/crypto/amcc/crypto4xx_core.c
+++ b/drivers/crypto/amcc/crypto4xx_core.c
@@ -40,9 +40,11 @@
#include <crypto/ctr.h>
#include <crypto/gcm.h>
#include <crypto/sha.h>
+#include <crypto/rng.h>
#include <crypto/scatterwalk.h>
#include <crypto/skcipher.h>
#include <crypto/internal/aead.h>
+#include <crypto/internal/rng.h>
#include <crypto/internal/skcipher.h>
#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 <linux/ratelimit.h>
+#include <linux/mutex.h>
#include <crypto/internal/hash.h>
#include <crypto/internal/aead.h>
+#include <crypto/internal/rng.h>
#include <crypto/internal/skcipher.h>
#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
--
2.20.1
