Add support for setting and/or updating passphrase on the Intel nvdimms.
The passphrase is pulled from userspace through the kernel key management.
We trigger the update via writing "update <old_keyid> <new_keyid>" to the
sysfs attribute "security". If no <old_keyid> exists (for enabling security)
then a 0 should be used. The state of the security can also be read via the
"security" attribute. libnvdimm will generically support the key_change
API call.
Signed-off-by: Dave Jiang <dave.ji...@intel.com>
---
drivers/acpi/nfit/intel.c | 68 ++++++++++++
drivers/nvdimm/dimm_devs.c | 248 ++++++++++++++++++++++++++++++++++++++++++++
include/linux/libnvdimm.h | 5 +
3 files changed, 321 insertions(+)
diff --git a/drivers/acpi/nfit/intel.c b/drivers/acpi/nfit/intel.c
index 4bfc1c1da339..314eae7e02d7 100644
--- a/drivers/acpi/nfit/intel.c
+++ b/drivers/acpi/nfit/intel.c
@@ -18,6 +18,73 @@
#include "intel.h"
#include "nfit.h"
+/*
+ * The update passphrase takes the old passphrase and the new passphrase
+ * and send those to the nvdimm. The nvdimm will verify the old
+ * passphrase and then update it with the new passphrase if pending
+ * verification. The function will pass in a zeroed passphrase field
+ * if the old passphrase is NULL. This typically happens when we are
+ * enabling security from the disabled state.
+ */
+static int intel_dimm_security_update_passphrase(
+ struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
+ const struct nvdimm_key_data *old_data,
+ const struct nvdimm_key_data *new_data)
+{
+ struct nvdimm_bus_descriptor *nd_desc = to_nd_desc(nvdimm_bus);
+ int cmd_rc, rc = 0;
+ struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
+ struct {
+ struct nd_cmd_pkg pkg;
+ struct nd_intel_set_passphrase cmd;
+ } nd_cmd = {
+ .pkg = {
+ .nd_command = NVDIMM_INTEL_SET_PASSPHRASE,
+ .nd_family = NVDIMM_FAMILY_INTEL,
+ .nd_size_in = ND_INTEL_PASSPHRASE_SIZE * 2,
+ .nd_size_out = ND_INTEL_STATUS_SIZE,
+ .nd_fw_size = ND_INTEL_STATUS_SIZE,
+ },
+ .cmd = {
+ .status = 0,
+ },
+ };
+
+ if (!test_bit(NVDIMM_INTEL_SET_PASSPHRASE, &nfit_mem->dsm_mask))
+ return -ENOTTY;
+
+ if (old_data)
+ memcpy(nd_cmd.cmd.old_pass, old_data->data,
+ sizeof(nd_cmd.cmd.old_pass));
+ else
+ memset(nd_cmd.cmd.old_pass, 0, sizeof(nd_cmd.cmd.old_pass));
+ memcpy(nd_cmd.cmd.new_pass, new_data->data,
+ sizeof(nd_cmd.cmd.new_pass));
+ rc = nd_desc->ndctl(nd_desc, nvdimm, ND_CMD_CALL, &nd_cmd,
+ sizeof(nd_cmd), &cmd_rc);
+ if (rc < 0)
+ goto out;
+ if (cmd_rc < 0) {
+ rc = cmd_rc;
+ goto out;
+ }
+
+ switch (nd_cmd.cmd.status) {
+ case 0:
+ break;
+ case ND_INTEL_STATUS_INVALID_PASS:
+ rc = -EINVAL;
+ goto out;
+ case ND_INTEL_STATUS_INVALID_STATE:
+ default:
+ rc = -ENXIO;
+ goto out;
+ }
+
+ out:
+ return rc;
+}
+
static int intel_dimm_security_unlock(struct nvdimm_bus *nvdimm_bus,
struct nvdimm *nvdimm, const struct nvdimm_key_data *nkey)
{
@@ -149,4 +216,5 @@ static int intel_dimm_security_state(struct nvdimm_bus
*nvdimm_bus,
const struct nvdimm_security_ops intel_security_ops = {
.state = intel_dimm_security_state,
.unlock = intel_dimm_security_unlock,
+ .change_key = intel_dimm_security_update_passphrase,
};
diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c
index e7f4c8a2b242..becbe670b572 100644
--- a/drivers/nvdimm/dimm_devs.c
+++ b/drivers/nvdimm/dimm_devs.c
@@ -20,6 +20,7 @@
#include <linux/mm.h>
#include <linux/cred.h>
#include <linux/key.h>
+#include <linux/key-type.h>
#include <keys/user-type.h>
#include "nd-core.h"
#include "label.h"
@@ -49,6 +50,58 @@ static struct key *nvdimm_get_key(struct device *dev)
return nvdimm->key;
}
+/*
+ * Replacing the user key with a kernel key. The function expects that
+ * we hold the sem for the key passed in. The function will release that
+ * sem when done process. We will also hold the sem for the valid new key
+ * returned.
+ */
+static struct key *nvdimm_replace_key(struct key *key)
+{
+ struct key *new_key;
+ struct user_key_payload *payload;
+ int rc;
+
+ new_key = key_alloc(&key_type_logon, key->description,
+ GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, current_cred(),
+ KEY_POS_SEARCH, KEY_ALLOC_NOT_IN_QUOTA, NULL);
+ if (IS_ERR(new_key))
+ return NULL;
+
+ payload = key->payload.data[0];
+ rc = key_instantiate_and_link(new_key, payload->data,
+ payload->datalen, NULL, NULL);
+ up_read(&key->sem);
+ if (rc < 0) {
+ key_put(new_key);
+ return NULL;
+ }
+
+ key_put(key);
+
+ down_read(&new_key->sem);
+ return new_key;
+}
+
+/*
+ * Retrieve user injected key
+ */
+static struct key *nvdimm_lookup_user_key(struct device *dev,
+ key_serial_t id)
+{
+ key_ref_t keyref;
+ struct key *key;
+
+ keyref = lookup_user_key(id, 0, 0);
+ if (IS_ERR(keyref))
+ return NULL;
+
+ key = key_ref_to_ptr(keyref);
+ dev_dbg(dev, "%s: key found: %d\n", __func__, key_serial(key));
+
+ return key;
+}
+
/*
* Retrieve kernel key for DIMM and request from user space if necessary.
*/
@@ -66,6 +119,49 @@ static struct key *nvdimm_request_key(struct device *dev)
return key;
}
+struct key *nvdimm_get_and_verify_key(struct device *dev,
+ unsigned int user_key_id)
+{
+ struct key *user_key, *key;
+ struct user_key_payload *upayload, *payload;
+ int rc = 0;
+
+ key = nvdimm_get_key(dev);
+ /* we don't have a cached key */
+ if (!key) {
+ dev_dbg(dev, "No cached kernel key\n");
+ return NULL;
+ }
+
+ user_key = nvdimm_lookup_user_key(dev, user_key_id);
+ if (!user_key) {
+ dev_dbg(dev, "Old user key lookup failed\n");
+ rc = -EINVAL;
+ goto out;
+ }
+
+ down_read(&key->sem);
+ payload = key->payload.data[0];
+ down_read(&user_key->sem);
+ upayload = user_key->payload.data[0];
+
+ if (memcmp(payload->data, upayload->data,
+ NVDIMM_PASSPHRASE_LEN) != 0) {
+ rc = -EINVAL;
+ dev_warn(dev, "Supplied old user key fails check.\n");
+ }
+
+ up_read(&user_key->sem);
+ key_put(user_key);
+ up_read(&key->sem);
+
+out:
+ key_put(key);
+ if (rc < 0)
+ key = ERR_PTR(rc);
+ return key;
+}
+
static int nvdimm_check_key_len(unsigned short len)
{
if (len == NVDIMM_PASSPHRASE_LEN)
@@ -145,6 +241,103 @@ int nvdimm_security_unlock_dimm(struct device *dev)
return rc;
}
+static int nvdimm_security_change_key(struct device *dev,
+ unsigned int old_keyid, unsigned int new_keyid)
+{
+ struct nvdimm *nvdimm = to_nvdimm(dev);
+ struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
+ struct key *key, *old_key;
+ int rc;
+ void *old_data = NULL, *new_data;
+ bool update = false;
+ struct user_key_payload *payload, *old_payload;
+
+ if (!nvdimm->security_ops)
+ return -EOPNOTSUPP;
+
+ if (nvdimm->state == NVDIMM_SECURITY_FROZEN)
+ return -EBUSY;
+
+ /* look for a key from keyring if exists and remove */
+ old_key = nvdimm_get_and_verify_key(dev, old_keyid);
+ if (IS_ERR(old_key))
+ return PTR_ERR(old_key);
+ if (old_key) {
+ dev_dbg(dev, "%s: old key: %#x\n",
+ __func__, key_serial(old_key));
+ update = true;
+ }
+
+ /* request new key from userspace */
+ key = nvdimm_lookup_user_key(dev, new_keyid);
+ if (!key) {
+ dev_dbg(dev, "%s: failed to acquire new key\n", __func__);
+ rc = -ENXIO;
+ goto out;
+ }
+
+ dev_dbg(dev, "%s: new key: %#x\n", __func__, key_serial(key));
+
+ down_read(&key->sem);
+ payload = key->payload.data[0];
+ rc = nvdimm_check_key_len(payload->datalen);
+ if (rc < 0) {
+ up_read(&key->sem);
+ goto out;
+ }
+
+ /* we need to check description as well */
+
+ if (!update)
+ key = nvdimm_replace_key(key);
+
+ /*
+ * We don't need to release key->sem here because nvdimm_repalce_key
+ * will.
+ */
+ if (!key)
+ goto out;
+
+ payload = key->payload.data[0];
+
+ if (old_key) {
+ down_read(&old_key->sem);
+ old_payload = old_key->payload.data[0];
+ old_data = old_payload->data;
+ }
+
+ new_data = payload->data;
+
+ rc = nvdimm->security_ops->change_key(nvdimm_bus, nvdimm, old_data,
+ new_data);
+ /* copy new payload to old payload */
+ if (rc == 0) {
+ if (update)
+ key_update(make_key_ref(old_key, 1), new_data,
+ old_key->datalen);
+ } else
+ dev_warn(dev, "key update failed\n");
+ if (old_key)
+ up_read(&old_key->sem);
+ up_read(&key->sem);
+
+ if (!update) {
+ if (rc == 0) {
+ key_link(nvdimm_keyring, key);
+ nvdimm->key = key;
+ } else
+ key_invalidate(key);
+ }
+ nvdimm_security_get_state(dev);
+
+ out:
+ if (old_key)
+ key_put(old_key);
+ if (key)
+ key_put(key);
+ return rc;
+}
+
/*
* Retrieve bus and dimm handle and return if this bus supports
* get_config_data commands
@@ -502,11 +695,66 @@ static ssize_t available_slots_show(struct device *dev,
}
static DEVICE_ATTR_RO(available_slots);
+static ssize_t security_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct nvdimm *nvdimm = to_nvdimm(dev);
+
+ switch (nvdimm->state) {
+ case NVDIMM_SECURITY_DISABLED:
+ return sprintf(buf, "disabled\n");
+ case NVDIMM_SECURITY_UNLOCKED:
+ return sprintf(buf, "unlocked\n");
+ case NVDIMM_SECURITY_LOCKED:
+ return sprintf(buf, "locked\n");
+ case NVDIMM_SECURITY_FROZEN:
+ return sprintf(buf, "frozen\n");
+ case NVDIMM_SECURITY_UNSUPPORTED:
+ default:
+ return sprintf(buf, "unsupported\n");
+ }
+
+ return -ENOTTY;
+}
+
+#define SEC_CMD_SIZE 128
+static ssize_t security_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t len)
+
+{
+ struct nvdimm *nvdimm = to_nvdimm(dev);
+ struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
+ ssize_t rc = -EINVAL;
+ unsigned int new_key = 0, old_key = 0;
+ char cmd[SEC_CMD_SIZE];
+
+ if (len > SEC_CMD_SIZE)
+ return -EINVAL;
+
+ wait_nvdimm_bus_probe_idle(&nvdimm_bus->dev);
+ if (atomic_read(&nvdimm->busy))
+ return -EBUSY;
+
+ sscanf(buf, "%s %u %u", cmd, &old_key, &new_key);
+ if (sysfs_streq(cmd, "update")) {
+ dev_dbg(dev, "update %u %u\n", old_key, new_key);
+ rc = nvdimm_security_change_key(dev, old_key, new_key);
+ } else
+ return -EINVAL;
+
+ if (rc == 0)
+ rc = len;
+
+ return rc;
+}
+static DEVICE_ATTR_RW(security);
+
static struct attribute *nvdimm_attributes[] = {
&dev_attr_state.attr,
&dev_attr_flags.attr,
&dev_attr_commands.attr,
&dev_attr_available_slots.attr,
+ &dev_attr_security.attr,
NULL,
};
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index 257ff2637ce1..bd6a413164ee 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -160,6 +160,7 @@ enum nvdimm_security_state {
NVDIMM_SECURITY_DISABLED,
NVDIMM_SECURITY_UNLOCKED,
NVDIMM_SECURITY_LOCKED,
+ NVDIMM_SECURITY_FROZEN,
NVDIMM_SECURITY_UNSUPPORTED,
};
@@ -177,6 +178,10 @@ struct nvdimm_security_ops {
int (*unlock)(struct nvdimm_bus *nvdimm_bus,
struct nvdimm *nvdimm,
const struct nvdimm_key_data *nkey);
+ int (*change_key)(struct nvdimm_bus *nvdimm_bus,
+ struct nvdimm *nvdimm,
+ const struct nvdimm_key_data *old_data,
+ const struct nvdimm_key_data *new_data);
};
void badrange_init(struct badrange *badrange);
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