mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git
synced 2026-04-27 11:58:32 -04:00
c391714c04
The kfree_sensitive is a kernel API to clear sensitive information that should not be leaked to other future users of the same memory objects and free the memory. Its function is the same as the combination of memzero_explicit and kfree. Thus, we can replace the combination APIs with the single kfree_sensitive API. Signed-off-by: Jason Wang <wangborong@cdjrlc.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
127 lines
2.9 KiB
C
127 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* sun8i-ce-trng.c - hardware cryptographic offloader for
|
|
* Allwinner H3/A64/H5/H2+/H6/R40 SoC
|
|
*
|
|
* Copyright (C) 2015-2020 Corentin Labbe <clabbe@baylibre.com>
|
|
*
|
|
* This file handle the TRNG
|
|
*
|
|
* You could find a link for the datasheet in Documentation/arm/sunxi.rst
|
|
*/
|
|
#include "sun8i-ce.h"
|
|
#include <linux/dma-mapping.h>
|
|
#include <linux/pm_runtime.h>
|
|
#include <linux/hw_random.h>
|
|
/*
|
|
* Note that according to the algorithm ID, 2 versions of the TRNG exists,
|
|
* The first present in H3/H5/R40/A64 and the second present in H6.
|
|
* This file adds support for both, but only the second is working
|
|
* reliabily according to rngtest.
|
|
**/
|
|
|
|
static int sun8i_ce_trng_read(struct hwrng *rng, void *data, size_t max, bool wait)
|
|
{
|
|
struct sun8i_ce_dev *ce;
|
|
dma_addr_t dma_dst;
|
|
int err = 0;
|
|
int flow = 3;
|
|
unsigned int todo;
|
|
struct sun8i_ce_flow *chan;
|
|
struct ce_task *cet;
|
|
u32 common;
|
|
void *d;
|
|
|
|
ce = container_of(rng, struct sun8i_ce_dev, trng);
|
|
|
|
/* round the data length to a multiple of 32*/
|
|
todo = max + 32;
|
|
todo -= todo % 32;
|
|
|
|
d = kzalloc(todo, GFP_KERNEL | GFP_DMA);
|
|
if (!d)
|
|
return -ENOMEM;
|
|
|
|
#ifdef CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG
|
|
ce->hwrng_stat_req++;
|
|
ce->hwrng_stat_bytes += todo;
|
|
#endif
|
|
|
|
dma_dst = dma_map_single(ce->dev, d, todo, DMA_FROM_DEVICE);
|
|
if (dma_mapping_error(ce->dev, dma_dst)) {
|
|
dev_err(ce->dev, "Cannot DMA MAP DST\n");
|
|
err = -EFAULT;
|
|
goto err_dst;
|
|
}
|
|
|
|
err = pm_runtime_get_sync(ce->dev);
|
|
if (err < 0) {
|
|
pm_runtime_put_noidle(ce->dev);
|
|
goto err_pm;
|
|
}
|
|
|
|
mutex_lock(&ce->rnglock);
|
|
chan = &ce->chanlist[flow];
|
|
|
|
cet = &chan->tl[0];
|
|
memset(cet, 0, sizeof(struct ce_task));
|
|
|
|
cet->t_id = cpu_to_le32(flow);
|
|
common = ce->variant->trng | CE_COMM_INT;
|
|
cet->t_common_ctl = cpu_to_le32(common);
|
|
|
|
/* recent CE (H6) need length in bytes, in word otherwise */
|
|
if (ce->variant->trng_t_dlen_in_bytes)
|
|
cet->t_dlen = cpu_to_le32(todo);
|
|
else
|
|
cet->t_dlen = cpu_to_le32(todo / 4);
|
|
|
|
cet->t_sym_ctl = 0;
|
|
cet->t_asym_ctl = 0;
|
|
|
|
cet->t_dst[0].addr = cpu_to_le32(dma_dst);
|
|
cet->t_dst[0].len = cpu_to_le32(todo / 4);
|
|
ce->chanlist[flow].timeout = todo;
|
|
|
|
err = sun8i_ce_run_task(ce, 3, "TRNG");
|
|
mutex_unlock(&ce->rnglock);
|
|
|
|
pm_runtime_put(ce->dev);
|
|
|
|
err_pm:
|
|
dma_unmap_single(ce->dev, dma_dst, todo, DMA_FROM_DEVICE);
|
|
|
|
if (!err) {
|
|
memcpy(data, d, max);
|
|
err = max;
|
|
}
|
|
err_dst:
|
|
kfree_sensitive(d);
|
|
return err;
|
|
}
|
|
|
|
int sun8i_ce_hwrng_register(struct sun8i_ce_dev *ce)
|
|
{
|
|
int ret;
|
|
|
|
if (ce->variant->trng == CE_ID_NOTSUPP) {
|
|
dev_info(ce->dev, "TRNG not supported\n");
|
|
return 0;
|
|
}
|
|
ce->trng.name = "sun8i Crypto Engine TRNG";
|
|
ce->trng.read = sun8i_ce_trng_read;
|
|
ce->trng.quality = 1000;
|
|
|
|
ret = hwrng_register(&ce->trng);
|
|
if (ret)
|
|
dev_err(ce->dev, "Fail to register the TRNG\n");
|
|
return ret;
|
|
}
|
|
|
|
void sun8i_ce_hwrng_unregister(struct sun8i_ce_dev *ce)
|
|
{
|
|
if (ce->variant->trng == CE_ID_NOTSUPP)
|
|
return;
|
|
hwrng_unregister(&ce->trng);
|
|
}
|