Commit d072bfa4 authored by Christian Lamparter's avatar Christian Lamparter Committed by Herbert Xu
Browse files

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: default avatarChristian Lamparter <chunkeey@gmail.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 12b8567f

drivers/crypto/amcc/crypto4xx_core.c

+87 −0
Original line number Diff line number Diff line
@@ -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);

drivers/crypto/amcc/crypto4xx_core.h

+4 −0
Original line number Diff line number Diff line
@@ -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;

};

drivers/crypto/amcc/crypto4xx_reg_def.h

+1 −0
Original line number Diff line number Diff line
@@ -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

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