linux/drivers/nvdimm/dimm.c
Dave Jiang 4c6926a23b acpi/nfit, libnvdimm: Add unlock of nvdimm support for Intel DIMMs
Add support to unlock the dimm via the kernel key management APIs. The
passphrase is expected to be pulled from userspace through keyutils.
The key management and sysfs attributes are libnvdimm generic.

Encrypted keys are used to protect the nvdimm passphrase at rest. The
master key can be a trusted-key sealed in a TPM, preferred, or an
encrypted-key, more flexible, but more exposure to a potential attacker.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Co-developed-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-13 17:54:13 -08:00

153 lines
3.4 KiB
C

/*
* Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
#include <linux/vmalloc.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/sizes.h>
#include <linux/ndctl.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/nd.h>
#include "label.h"
#include "nd.h"
static int nvdimm_probe(struct device *dev)
{
struct nvdimm_drvdata *ndd;
int rc;
rc = nvdimm_check_config_data(dev);
if (rc) {
/* not required for non-aliased nvdimm, ex. NVDIMM-N */
if (rc == -ENOTTY)
rc = 0;
return rc;
}
/*
* The locked status bit reflects explicit status codes from the
* label reading commands, revalidate it each time the driver is
* activated and re-reads the label area.
*/
nvdimm_clear_locked(dev);
ndd = kzalloc(sizeof(*ndd), GFP_KERNEL);
if (!ndd)
return -ENOMEM;
dev_set_drvdata(dev, ndd);
ndd->dpa.name = dev_name(dev);
ndd->ns_current = -1;
ndd->ns_next = -1;
ndd->dpa.start = 0;
ndd->dpa.end = -1;
ndd->dev = dev;
get_device(dev);
kref_init(&ndd->kref);
/*
* Attempt to unlock, if the DIMM supports security commands,
* otherwise the locked indication is determined by explicit
* status codes from the label reading commands.
*/
rc = nvdimm_security_unlock(dev);
if (rc < 0)
dev_err(dev, "failed to unlock dimm: %d\n", rc);
/*
* EACCES failures reading the namespace label-area-properties
* are interpreted as the DIMM capacity being locked but the
* namespace labels themselves being accessible.
*/
rc = nvdimm_init_nsarea(ndd);
if (rc == -EACCES) {
/*
* See nvdimm_namespace_common_probe() where we fail to
* allow namespaces to probe while the DIMM is locked,
* but we do allow for namespace enumeration.
*/
nvdimm_set_locked(dev);
rc = 0;
}
if (rc)
goto err;
/*
* EACCES failures reading the namespace label-data are
* interpreted as the label area being locked in addition to the
* DIMM capacity. We fail the dimm probe to prevent regions from
* attempting to parse the label area.
*/
rc = nd_label_data_init(ndd);
if (rc == -EACCES)
nvdimm_set_locked(dev);
if (rc)
goto err;
dev_dbg(dev, "config data size: %d\n", ndd->nsarea.config_size);
nvdimm_bus_lock(dev);
if (ndd->ns_current >= 0) {
rc = nd_label_reserve_dpa(ndd);
if (rc == 0)
nvdimm_set_aliasing(dev);
}
nvdimm_bus_unlock(dev);
if (rc)
goto err;
return 0;
err:
put_ndd(ndd);
return rc;
}
static int nvdimm_remove(struct device *dev)
{
struct nvdimm_drvdata *ndd = dev_get_drvdata(dev);
if (!ndd)
return 0;
nvdimm_bus_lock(dev);
dev_set_drvdata(dev, NULL);
nvdimm_bus_unlock(dev);
put_ndd(ndd);
return 0;
}
static struct nd_device_driver nvdimm_driver = {
.probe = nvdimm_probe,
.remove = nvdimm_remove,
.drv = {
.name = "nvdimm",
},
.type = ND_DRIVER_DIMM,
};
int __init nvdimm_init(void)
{
return nd_driver_register(&nvdimm_driver);
}
void nvdimm_exit(void)
{
driver_unregister(&nvdimm_driver.drv);
}
MODULE_ALIAS_ND_DEVICE(ND_DEVICE_DIMM);