// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2015 Pengutronix, Steffen Trumtrar <[email protected]>
* Copyright (C) 2021 Pengutronix, Ahmad Fatoum <[email protected]>
*/
#define pr_fmt(fmt) "caam blob_gen: " fmt
#include <linux/bitfield.h>
#include <linux/device.h>
#include <soc/fsl/caam-blob.h>
#include "compat.h"
#include "desc_constr.h"
#include "desc.h"
#include "error.h"
#include "intern.h"
#include "jr.h"
#include "regs.h"
#define CAAM_BLOB_DESC_BYTES_MAX \
/* Command to initialize & stating length of descriptor */ \
(CAAM_CMD_SZ + \
/* Command to append the key-modifier + key-modifier data */ \
CAAM_CMD_SZ + CAAM_BLOB_KEYMOD_LENGTH + \
/* Command to include input key + pointer to the input key */ \
CAAM_CMD_SZ + CAAM_PTR_SZ_MAX + \
/* Command to include output key + pointer to the output key */ \
CAAM_CMD_SZ + CAAM_PTR_SZ_MAX + \
/* Command describing the operation to perform */ \
CAAM_CMD_SZ)
struct caam_blob_priv {
struct device jrdev;
};
struct caam_blob_job_result {
int err;
struct completion completion;
};
static void caam_blob_job_done(struct device *dev, u32 *desc, u32 err, void *context)
{
struct caam_blob_job_result *res = context;
int ecode = 0;
dev_dbg(dev, "%s %d: err 0x%x\n", __func__, __LINE__, err);
if (err)
ecode = caam_jr_strstatus(dev, err);
res->err = ecode;
/*
* Upon completion, desc points to a buffer containing a CAAM job
* descriptor which encapsulates data into an externally-storable
* blob.
*/
complete(&res->completion);
}
int caam_process_blob(struct caam_blob_priv *priv,
struct caam_blob_info *info, bool encap)
{
const struct caam_drv_private *ctrlpriv;
struct caam_blob_job_result testres;
struct device *jrdev = &priv->jrdev;
dma_addr_t dma_in, dma_out;
int op = OP_PCLID_BLOB;
size_t output_len;
u32 *desc;
u32 moo;
int ret;
if (info->key_mod_len > CAAM_BLOB_KEYMOD_LENGTH)
return -EINVAL;
if (encap) {
op |= OP_TYPE_ENCAP_PROTOCOL;
output_len = info->input_len + CAAM_BLOB_OVERHEAD;
} else {
op |= OP_TYPE_DECAP_PROTOCOL;
output_len = info->input_len - CAAM_BLOB_OVERHEAD;
}
desc = kzalloc(CAAM_BLOB_DESC_BYTES_MAX, GFP_KERNEL);
if (!desc)
return -ENOMEM;
dma_in = dma_map_single(jrdev, info->input, info->input_len,
DMA_TO_DEVICE);
if (dma_mapping_error(jrdev, dma_in)) {
dev_err(jrdev, "unable to map input DMA buffer\n");
ret = -ENOMEM;
goto out_free;
}
dma_out = dma_map_single(jrdev, info->output, output_len,
DMA_FROM_DEVICE);
if (dma_mapping_error(jrdev, dma_out)) {
dev_err(jrdev, "unable to map output DMA buffer\n");
ret = -ENOMEM;
goto out_unmap_in;
}
ctrlpriv = dev_get_drvdata(jrdev->parent);
moo = FIELD_GET(CSTA_MOO, rd_reg32(&ctrlpriv->ctrl->perfmon.status));
if (moo != CSTA_MOO_SECURE && moo != CSTA_MOO_TRUSTED)
dev_warn(jrdev,
"using insecure test key, enable HAB to use unique device key!\n");
/*
* A data blob is encrypted using a blob key (BK); a random number.
* The BK is used as an AES-CCM key. The initial block (B0) and the
* initial counter (Ctr0) are generated automatically and stored in
* Class 1 Context DWords 0+1+2+3. The random BK is stored in the
* Class 1 Key Register. Operation Mode is set to AES-CCM.
*/
init_job_desc(desc, 0);
append_key_as_imm(desc, info->key_mod, info->key_mod_len,
info->key_mod_len, CLASS_2 | KEY_DEST_CLASS_REG);
append_seq_in_ptr_intlen(desc, dma_in, info->input_len, 0);
append_seq_out_ptr_intlen(desc, dma_out, output_len, 0);
append_operation(desc, op);
print_hex_dump_debug("data@"__stringify(__LINE__)": ",
DUMP_PREFIX_ADDRESS, 16, 1, info->input,
info->input_len, false);
print_hex_dump_debug("jobdesc@"__stringify(__LINE__)": ",
DUMP_PREFIX_ADDRESS, 16, 1, desc,
desc_bytes(desc), false);
testres.err = 0;
init_completion(&testres.completion);
ret = caam_jr_enqueue(jrdev, desc, caam_blob_job_done, &testres);
if (ret == -EINPROGRESS) {
wait_for_completion(&testres.completion);
ret = testres.err;
print_hex_dump_debug("output@"__stringify(__LINE__)": ",
DUMP_PREFIX_ADDRESS, 16, 1, info->output,
output_len, false);
}
if (ret == 0)
info->output_len = output_len;
dma_unmap_single(jrdev, dma_out, output_len, DMA_FROM_DEVICE);
out_unmap_in:
dma_unmap_single(jrdev, dma_in, info->input_len, DMA_TO_DEVICE);
out_free:
kfree(desc);
return ret;
}
EXPORT_SYMBOL(caam_process_blob);
struct caam_blob_priv *caam_blob_gen_init(void)
{
struct caam_drv_private *ctrlpriv;
struct device *jrdev;
/*
* caam_blob_gen_init() may expectedly fail with -ENODEV, e.g. when
* CAAM driver didn't probe or when SoC lacks BLOB support. An
* error would be harsh in this case, so we stick to info level.
*/
jrdev = caam_jr_alloc();
if (IS_ERR(jrdev)) {
pr_info("job ring requested, but none currently available\n");
return ERR_PTR(-ENODEV);
}
ctrlpriv = dev_get_drvdata(jrdev->parent);
if (!ctrlpriv->blob_present) {
dev_info(jrdev, "no hardware blob generation support\n");
caam_jr_free(jrdev);
return ERR_PTR(-ENODEV);
}
return container_of(jrdev, struct caam_blob_priv, jrdev);
}
EXPORT_SYMBOL(caam_blob_gen_init);
void caam_blob_gen_exit(struct caam_blob_priv *priv)
{
caam_jr_free(&priv->jrdev);
}
EXPORT_SYMBOL(caam_blob_gen_exit);
Codebase Browser
linux