8:43 a.m.
On Fri, Mar 22, 2019 at 2:33 PM Dave Jiang <dave.jiang(a)intel.com> wrote:
Adding support to allow secure erase to happen when security state is not
enabled. Key data of 0's will be passed in.
I think I want to change this wording and patch title to say
"libnvdimm/security: Support a zero-key for secure-erase". Because we
are still passing a key and the kernel interface requires the key-id
parameter, we're just arranging for a special key to be used.
Signed-off-by: Dave Jiang <dave.jiang(a)intel.com>
---
drivers/nvdimm/security.c | 17 ++++++++++++-----
tools/testing/nvdimm/test/nfit.c | 3 +--
2 files changed, 13 insertions(+), 7 deletions(-)
diff --git a/drivers/nvdimm/security.c b/drivers/nvdimm/security.c
index f8bb746a549f..b7bd26030964 100644
--- a/drivers/nvdimm/security.c
+++ b/drivers/nvdimm/security.c
@@ -286,8 +286,9 @@ 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;
+ char *data, dummy_key[NVDIMM_PASSPHRASE_LEN];
Let's make this
static const char zero_key[NVDIMM_PASSPHRASE_LEN];
...and make it global.
/* The bus lock should be held at the top level of the call stack */
lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
@@ -319,11 +320,17 @@ 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 {
+ memset(dummy_key, 0, NVDIMM_PASSPHRASE_LEN);
...with the above change no need to do a memset.
+ data = dummy_key;
There may be hardware that actually expects zeroes so I'd rather be
explicit, because if it was truly "dummy" there would be no need to
initialize it.
+ }
- rc = nvdimm->sec.ops->erase(nvdimm, key_data(key), pass_type);
+ rc = nvdimm->sec.ops->erase(nvdimm, (void *)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 b579f962451d..9351a81ea945 100644
--- a/tools/testing/nvdimm/test/nfit.c
+++ b/tools/testing/nvdimm/test/nfit.c
@@ -1059,8 +1059,7 @@ 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) {
What does this have to do with the new zero-key?