acpi/nfit: Add support for Intel DSM 1.8 commands

Add command definition for security commands defined in Intel DSM
specification v1.8 [1]. This includes "get security state", "set
passphrase", "unlock unit", "freeze lock", "secure erase", "overwrite",
"overwrite query", "master passphrase enable/disable", and "master
erase", . Since this adds several Intel definitions, move the relevant
bits to their own header.

These commands mutate physical data, but that manipulation is not cache
coherent. The requirement to flush and invalidate caches makes these
commands unsuitable to be called from userspace, so extra logic is added
to detect and block these commands from being submitted via the ioctl
command submission path.

Lastly, the commands may contain sensitive key material that should not
be dumped in a standard debug session. Update the nvdimm-command
payload-dump facility to move security command payloads behind a
default-off compile time switch.

[1]: http://pmem.io/documents/NVDIMM_DSM_Interface-V1.8.pdf

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

1 files changed, 42 insertions, 4 deletions

diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 14d9f5bea015..58fb4ce42548 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -24,6 +24,7 @@
 #include <linux/nd.h>
 #include <asm/cacheflush.h>
 #include <acpi/nfit.h>
+#include "intel.h"
 #include "nfit.h"
 #include "intel.h"
 
@@ -380,6 +381,14 @@ static u8 nfit_dsm_revid(unsigned family, unsigned func)
 			[NVDIMM_INTEL_QUERY_FWUPDATE] = 2,
 			[NVDIMM_INTEL_SET_THRESHOLD] = 2,
 			[NVDIMM_INTEL_INJECT_ERROR] = 2,
+			[NVDIMM_INTEL_GET_SECURITY_STATE] = 2,
+			[NVDIMM_INTEL_SET_PASSPHRASE] = 2,
+			[NVDIMM_INTEL_DISABLE_PASSPHRASE] = 2,
+			[NVDIMM_INTEL_UNLOCK_UNIT] = 2,
+			[NVDIMM_INTEL_FREEZE_LOCK] = 2,
+			[NVDIMM_INTEL_SECURE_ERASE] = 2,
+			[NVDIMM_INTEL_OVERWRITE] = 2,
+			[NVDIMM_INTEL_QUERY_OVERWRITE] = 2,
 		},
 	};
 	u8 id;
@@ -394,6 +403,17 @@ static u8 nfit_dsm_revid(unsigned family, unsigned func)
 	return id;
 }
 
+static bool payload_dumpable(struct nvdimm *nvdimm, unsigned int func)
+{
+	struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
+
+	if (nfit_mem && nfit_mem->family == NVDIMM_FAMILY_INTEL
+			&& func >= NVDIMM_INTEL_GET_SECURITY_STATE
+			&& func <= NVDIMM_INTEL_MASTER_SECURE_ERASE)
+		return IS_ENABLED(CONFIG_NFIT_SECURITY_DEBUG);
+	return true;
+}
+
 int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm,
 		unsigned int cmd, void *buf, unsigned int buf_len, int *cmd_rc)
 {
@@ -478,9 +498,10 @@ int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm,
 
 	dev_dbg(dev, "%s cmd: %d: func: %d input length: %d\n",
 		dimm_name, cmd, func, in_buf.buffer.length);
-	print_hex_dump_debug("nvdimm in  ", DUMP_PREFIX_OFFSET, 4, 4,
-			in_buf.buffer.pointer,
-			min_t(u32, 256, in_buf.buffer.length), true);
+	if (payload_dumpable(nvdimm, func))
+		print_hex_dump_debug("nvdimm in  ", DUMP_PREFIX_OFFSET, 4, 4,
+				in_buf.buffer.pointer,
+				min_t(u32, 256, in_buf.buffer.length), true);
 
 	/* call the BIOS, prefer the named methods over _DSM if available */
 	if (nvdimm && cmd == ND_CMD_GET_CONFIG_SIZE
@@ -3337,7 +3358,7 @@ static int acpi_nfit_flush_probe(struct nvdimm_bus_descriptor *nd_desc)
 	return 0;
 }
 
-static int acpi_nfit_clear_to_send(struct nvdimm_bus_descriptor *nd_desc,
+static int __acpi_nfit_clear_to_send(struct nvdimm_bus_descriptor *nd_desc,
 		struct nvdimm *nvdimm, unsigned int cmd)
 {
 	struct acpi_nfit_desc *acpi_desc = to_acpi_nfit_desc(nd_desc);
@@ -3359,6 +3380,23 @@ static int acpi_nfit_clear_to_send(struct nvdimm_bus_descriptor *nd_desc,
 	return 0;
 }
 
+/* prevent security commands from being issued via ioctl */
+static int acpi_nfit_clear_to_send(struct nvdimm_bus_descriptor *nd_desc,
+		struct nvdimm *nvdimm, unsigned int cmd, void *buf)
+{
+	struct nd_cmd_pkg *call_pkg = buf;
+	unsigned int func;
+
+	if (nvdimm && cmd == ND_CMD_CALL &&
+			call_pkg->nd_family == NVDIMM_FAMILY_INTEL) {
+		func = call_pkg->nd_command;
+		if ((1 << func) & NVDIMM_INTEL_SECURITY_CMDMASK)
+			return -EOPNOTSUPP;
+	}
+
+	return __acpi_nfit_clear_to_send(nd_desc, nvdimm, cmd);
+}
+
 int acpi_nfit_ars_rescan(struct acpi_nfit_desc *acpi_desc,
 		enum nfit_ars_state req_type)
 {