lkml.org 
[lkml]   [2008]   [Mar]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [patch 2/2] zcrypt: add support for large random numbers
On Fri, 14 Mar 2008 10:25:25 +0100 Martin Schwidefsky wrote:

> This patch allows user space applications to access large amounts of
> truly random data. The random data source is the build-in hardware
> random number generator on the CEX2C cards.
> ---
>
> drivers/crypto/Kconfig | 1
> drivers/s390/crypto/zcrypt_api.c | 120 +++++++++++++++++++++
> drivers/s390/crypto/zcrypt_api.h | 8 +
> drivers/s390/crypto/zcrypt_pcixcc.c | 199 +++++++++++++++++++++++++++++++++++-
> 4 files changed, 327 insertions(+), 1 deletion(-)
>
> Index: quilt-2.6/drivers/s390/crypto/zcrypt_api.c
> ===================================================================
> --- quilt-2.6.orig/drivers/s390/crypto/zcrypt_api.c
> +++ quilt-2.6/drivers/s390/crypto/zcrypt_api.c
> @@ -36,6 +36,7 @@
> #include <linux/compat.h>
> #include <asm/atomic.h>
> #include <asm/uaccess.h>
> +#include <linux/hw_random.h>
>
> #include "zcrypt_api.h"
>

> @@ -1041,6 +1094,73 @@ out:
> return count;
> }
>
> +static int zcrypt_rng_device_count;
> +static u32 *zcrypt_rng_buffer;
> +static int zcrypt_rng_buffer_index;
> +static DEFINE_MUTEX(zcrypt_rng_mutex);
> +
> +static int zcrypt_rng_data_read(struct hwrng *rng, u32 *data)
> +{
> + int rc;
> +
> + /**
> + * We don't need locking here because the RNG API guarantees serialized
> + * read method calls.
> + */

Hi,
Linux kernel uses "/**" to indicate the beginning of kernel-doc
notation, so when the comment block is not kernel-doc, please don't
use that /** to begin the comment block.
(multiple occurrences of this)

> + if (zcrypt_rng_buffer_index == 0) {
> + rc = zcrypt_rng((char *) zcrypt_rng_buffer);
> + if (rc < 0)
> + return -EIO;
> + zcrypt_rng_buffer_index = rc / sizeof *data;
> + }
> + *data = zcrypt_rng_buffer[--zcrypt_rng_buffer_index];
> + return sizeof *data;
> +}
> +
> +static struct hwrng zcrypt_rng_dev = {
> + .name = "zcrypt",
> + .data_read = zcrypt_rng_data_read,
> +};
> +
> +static int zcrypt_rng_device_add(void)
> +{
...
> +}


> Index: quilt-2.6/drivers/s390/crypto/zcrypt_pcixcc.c
> ===================================================================
> --- quilt-2.6.orig/drivers/s390/crypto/zcrypt_pcixcc.c
> +++ quilt-2.6/drivers/s390/crypto/zcrypt_pcixcc.c
> @@ -356,6 +356,55 @@ static int XCRB_msg_to_type6CPRB_msgX(st
> }
>
> /**
> + * Prepare a type6 CPRB message for random number generation
> + *
> + * @ap_dev: AP device pointer
> + * @ap_msg: pointer to AP message
> + */

This one is almost kernel-doc. Just put the function name plus a
hyphen/dash on the first line and remove the almost-blank line:

/**
* rng_type6CPRB_msgX - Prepare a type6 CPRB message for random number generation
* @ap_dev: AP device pointer
* @ap_msg: pointer to AP message
*/

See Documentation/kernel-doc-nano-HOWTO.txt for more info/details,
or ask me/lkml.

> +static void rng_type6CPRB_msgX(struct ap_device *ap_dev,
> + struct ap_message *ap_msg,
> + unsigned random_number_length)
> +{

...

> +}
> +
> +/**
> * Copy results from a type 86 ICA reply message back to user space.
> *
> * @zdev: crypto device pointer

> @@ -736,6 +830,42 @@ out_free:
> }
>
> /**
> + * The request distributor calls this function if it picked the PCIXCC/CEX2C
> + * device to generate random data.
> + * @zdev: pointer to zcrypt_device structure that identifies the
> + * PCIXCC/CEX2C device to the request distributor
> + * @buffer: pointer to a memory page to return random data
> + */
> +
> +static long zcrypt_pcixcc_rng(struct zcrypt_device *zdev,
> + char *buffer)
> +{
...
> +}
> +
> +/**
> * The crypto operations for a PCIXCC/CEX2C card.
> */
> static struct zcrypt_ops zcrypt_pcixcc_ops = {
> @@ -859,6 +996,58 @@ out_free:
> }
>
> /**
> + * Large random number detection function. Its sends a message to a pcixcc
> + * card to find out if large random numbers are supported.
> + * @ap_dev: pointer to the AP device.
> + *
> + * Returns 1 if large random numbers are supported, 0 if not and < 0 on error.
> + */
> +static int zcrypt_pcixcc_rng_supported(struct ap_device *ap_dev)
> +{
...
> +}

---
~Randy

\
 
 \ /
  Last update: 2008-03-14 17:19    [W:0.081 / U:6.260 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site