summaryrefslogtreecommitdiffstats
path: root/drivers/nvdimm
diff options
context:
space:
mode:
authorDave Jiang <dave.jiang@intel.com>2018-12-07 18:33:30 +0100
committerDan Williams <dan.j.williams@intel.com>2018-12-21 21:44:41 +0100
commit03b65b22ada8115a7a7bfdf0789f6a94adfd6070 (patch)
treed8ac0a260db2dcac8b52ed36566bd9b89ab2d116 /drivers/nvdimm
parentacpi/nfit, libnvdimm: Add unlock of nvdimm support for Intel DIMMs (diff)
downloadlinux-03b65b22ada8115a7a7bfdf0789f6a94adfd6070.tar.xz
linux-03b65b22ada8115a7a7bfdf0789f6a94adfd6070.zip
acpi/nfit, libnvdimm: Add disable passphrase support to Intel nvdimm.
Add support to disable passphrase (security) for the Intel nvdimm. The passphrase used for disabling is pulled from an encrypted-key in the kernel user keyring. The action is triggered by writing "disable <keyid>" to the sysfs attribute "security". Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/nvdimm')
-rw-r--r--drivers/nvdimm/dimm_devs.c47
-rw-r--r--drivers/nvdimm/nd-core.h9
-rw-r--r--drivers/nvdimm/security.c63
3 files changed, 116 insertions, 3 deletions
diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c
index 8e0bd2ce4dd0..7f42cc4e119b 100644
--- a/drivers/nvdimm/dimm_devs.c
+++ b/drivers/nvdimm/dimm_devs.c
@@ -391,24 +391,65 @@ static ssize_t security_show(struct device *dev,
return -ENOTTY;
}
+#define OPS \
+ C( OP_FREEZE, "freeze", 1), \
+ C( OP_DISABLE, "disable", 2)
+#undef C
+#define C(a, b, c) a
+enum nvdimmsec_op_ids { OPS };
+#undef C
+#define C(a, b, c) { b, c }
+static struct {
+ const char *name;
+ int args;
+} ops[] = { OPS };
+#undef C
+
+#define SEC_CMD_SIZE 32
+#define KEY_ID_SIZE 10
+
static ssize_t __security_store(struct device *dev, const char *buf, size_t len)
{
struct nvdimm *nvdimm = to_nvdimm(dev);
ssize_t rc;
+ char cmd[SEC_CMD_SIZE+1], keystr[KEY_ID_SIZE+1],
+ nkeystr[KEY_ID_SIZE+1];
+ unsigned int key, newkey;
+ int i;
if (atomic_read(&nvdimm->busy))
return -EBUSY;
- if (sysfs_streq(buf, "freeze")) {
+ rc = sscanf(buf, "%"__stringify(SEC_CMD_SIZE)"s"
+ " %"__stringify(KEY_ID_SIZE)"s"
+ " %"__stringify(KEY_ID_SIZE)"s",
+ cmd, keystr, nkeystr);
+ if (rc < 1)
+ return -EINVAL;
+ for (i = 0; i < ARRAY_SIZE(ops); i++)
+ if (sysfs_streq(cmd, ops[i].name))
+ break;
+ if (i >= ARRAY_SIZE(ops))
+ return -EINVAL;
+ if (ops[i].args > 1)
+ rc = kstrtouint(keystr, 0, &key);
+ if (rc >= 0 && ops[i].args > 2)
+ rc = kstrtouint(nkeystr, 0, &newkey);
+ if (rc < 0)
+ return rc;
+
+ if (i == OP_FREEZE) {
dev_dbg(dev, "freeze\n");
rc = nvdimm_security_freeze(nvdimm);
+ } else if (i == OP_DISABLE) {
+ dev_dbg(dev, "disable %u\n", key);
+ rc = nvdimm_security_disable(nvdimm, key);
} else
return -EINVAL;
if (rc == 0)
rc = len;
return rc;
-
}
static ssize_t security_store(struct device *dev,
@@ -452,7 +493,7 @@ static umode_t nvdimm_visible(struct kobject *kobj, struct attribute *a, int n)
if (nvdimm->sec.state < 0)
return 0;
/* Are there any state mutation ops? */
- if (nvdimm->sec.ops->freeze)
+ if (nvdimm->sec.ops->freeze || nvdimm->sec.ops->disable)
return a->mode;
return 0444;
}
diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h
index 15eff40f55f6..d1351c0b1119 100644
--- a/drivers/nvdimm/nd-core.h
+++ b/drivers/nvdimm/nd-core.h
@@ -57,6 +57,15 @@ static inline enum nvdimm_security_state nvdimm_security_state(
return nvdimm->sec.ops->state(nvdimm);
}
int nvdimm_security_freeze(struct nvdimm *nvdimm);
+#if IS_ENABLED(CONFIG_NVDIMM_KEYS)
+int nvdimm_security_disable(struct nvdimm *nvdimm, unsigned int keyid);
+#else
+static inline int nvdimm_security_disable(struct nvdimm *nvdimm,
+ unsigned int keyid)
+{
+ return -EOPNOTSUPP;
+}
+#endif
/**
* struct blk_alloc_info - tracking info for BLK dpa scanning
diff --git a/drivers/nvdimm/security.c b/drivers/nvdimm/security.c
index 51d77a67a9fb..647a99dd3182 100644
--- a/drivers/nvdimm/security.c
+++ b/drivers/nvdimm/security.c
@@ -69,6 +69,36 @@ static struct key *nvdimm_request_key(struct nvdimm *nvdimm)
return key;
}
+static struct key *nvdimm_lookup_user_key(struct nvdimm *nvdimm,
+ key_serial_t id)
+{
+ key_ref_t keyref;
+ struct key *key;
+ struct encrypted_key_payload *epayload;
+ struct device *dev = &nvdimm->dev;
+
+ keyref = lookup_user_key(id, 0, 0);
+ if (IS_ERR(keyref))
+ return NULL;
+
+ key = key_ref_to_ptr(keyref);
+ if (key->type != &key_type_encrypted) {
+ key_put(key);
+ return NULL;
+ }
+ dev_dbg(dev, "%s: key found: %#x\n", __func__, key_serial(key));
+
+
+ down_read(&key->sem);
+ epayload = dereference_key_locked(key);
+ if (epayload->decrypted_datalen != NVDIMM_PASSPHRASE_LEN) {
+ up_read(&key->sem);
+ key_put(key);
+ key = NULL;
+ }
+ return key;
+}
+
static struct key *nvdimm_key_revalidate(struct nvdimm *nvdimm)
{
struct key *key;
@@ -146,3 +176,36 @@ int nvdimm_security_unlock(struct device *dev)
nvdimm_bus_unlock(dev);
return rc;
}
+
+int nvdimm_security_disable(struct nvdimm *nvdimm, unsigned int keyid)
+{
+ struct device *dev = &nvdimm->dev;
+ struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
+ struct key *key;
+ int rc;
+
+ /* The bus lock should be held at the top level of the call stack */
+ lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
+
+ if (!nvdimm->sec.ops || !nvdimm->sec.ops->disable
+ || nvdimm->sec.state < 0)
+ return -EOPNOTSUPP;
+
+ if (nvdimm->sec.state >= NVDIMM_SECURITY_FROZEN) {
+ dev_warn(dev, "Incorrect security state: %d\n",
+ nvdimm->sec.state);
+ return -EIO;
+ }
+
+ key = nvdimm_lookup_user_key(nvdimm, keyid);
+ if (!key)
+ return -ENOKEY;
+
+ rc = nvdimm->sec.ops->disable(nvdimm, key_data(key));
+ dev_dbg(dev, "key: %d disable: %s\n", key_serial(key),
+ rc == 0 ? "success" : "fail");
+
+ nvdimm_put_key(key);
+ nvdimm->sec.state = nvdimm_security_state(nvdimm);
+ return rc;
+}