libnvdimm/security: provide fix for secure-erase to use zero-key

Add a zero key in order to standardize hardware that want a key of 0's to
be passed. Some platforms defaults to a zero-key with security enabled
rather than allow the OS to enable the security. The zero key would allow
us to manage those platform as well. This also adds a fix to secure erase
so it can use the zero key to do crypto erase. Some other security commands
already use zero keys. This introduces a standard zero-key to allow
unification of semantics cross nvdimm security commands.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/nvdimm/security.c b/drivers/nvdimm/security.c
index f8bb746a549f7b993dcf61f052acde8303d11cae..6bea6852bf278f59bc322e3238a71999817db060 100644 (file)
--- a/drivers/nvdimm/security.c
+++ b/drivers/nvdimm/security.c
@@ -22,6 +22,8 @@ static bool key_revalidate = true;
 module_param(key_revalidate, bool, 0444);
 MODULE_PARM_DESC(key_revalidate, "Require key validation at init.");
 
+static const char zero_key[NVDIMM_PASSPHRASE_LEN];
+
 static void *key_data(struct key *key)
 {
        struct encrypted_key_payload *epayload = dereference_key_locked(key);
@@ -286,8 +288,9 @@ int nvdimm_security_erase(struct nvdimm *nvdimm, unsigned int keyid,
 {
        struct device *dev = &nvdimm->dev;
        struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
-       struct key *key;
+       struct key *key = NULL;
        int rc;
+       const void *data;
 
        /* The bus lock should be held at the top level of the call stack */
        lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
@@ -319,11 +322,15 @@ int nvdimm_security_erase(struct nvdimm *nvdimm, unsigned int keyid,
                return -EOPNOTSUPP;
        }
 
-       key = nvdimm_lookup_user_key(nvdimm, keyid, NVDIMM_BASE_KEY);
-       if (!key)
-               return -ENOKEY;
+       if (keyid != 0) {
+               key = nvdimm_lookup_user_key(nvdimm, keyid, NVDIMM_BASE_KEY);
+               if (!key)
+                       return -ENOKEY;
+               data = key_data(key);
+       } else
+               data = zero_key;
 
-       rc = nvdimm->sec.ops->erase(nvdimm, key_data(key), pass_type);
+       rc = nvdimm->sec.ops->erase(nvdimm, data, pass_type);
        dev_dbg(dev, "key: %d erase%s: %s\n", key_serial(key),
                        pass_type == NVDIMM_MASTER ? "(master)" : "(user)",
                        rc == 0 ? "success" : "fail");

diff --git a/tools/testing/nvdimm/test/nfit.c b/tools/testing/nvdimm/test/nfit.c
index b579f962451d6464035c6649ac714998c05a225f..cad719876ef45b0e1057dc3cc108429bae951288 100644 (file)
--- a/tools/testing/nvdimm/test/nfit.c
+++ b/tools/testing/nvdimm/test/nfit.c
@@ -225,6 +225,8 @@ static struct workqueue_struct *nfit_wq;
 
 static struct gen_pool *nfit_pool;
 
+static const char zero_key[NVDIMM_PASSPHRASE_LEN];
+
 static struct nfit_test *to_nfit_test(struct device *dev)
 {
        struct platform_device *pdev = to_platform_device(dev);
@@ -1059,8 +1061,7 @@ static int nd_intel_test_cmd_secure_erase(struct nfit_test *t,
        struct device *dev = &t->pdev.dev;
        struct nfit_test_sec *sec = &dimm_sec_info[dimm];
 
-       if (!(sec->state & ND_INTEL_SEC_STATE_ENABLED) ||
-                       (sec->state & ND_INTEL_SEC_STATE_FROZEN)) {
+       if (sec->state & ND_INTEL_SEC_STATE_FROZEN) {
                nd_cmd->status = ND_INTEL_STATUS_INVALID_STATE;
                dev_dbg(dev, "secure erase: wrong security state\n");
        } else if (memcmp(nd_cmd->passphrase, sec->passphrase,
@@ -1068,6 +1069,12 @@ static int nd_intel_test_cmd_secure_erase(struct nfit_test *t,
                nd_cmd->status = ND_INTEL_STATUS_INVALID_PASS;
                dev_dbg(dev, "secure erase: wrong passphrase\n");
        } else {
+               if (!(sec->state & ND_INTEL_SEC_STATE_ENABLED)
+                               && (memcmp(nd_cmd->passphrase, zero_key,
+                                       ND_INTEL_PASSPHRASE_SIZE) != 0)) {
+                       dev_dbg(dev, "invalid zero key\n");
+                       return 0;
+               }
                memset(sec->passphrase, 0, ND_INTEL_PASSPHRASE_SIZE);
                memset(sec->master_passphrase, 0, ND_INTEL_PASSPHRASE_SIZE);
                sec->state = 0;