gsctool: support for enabling/disabling TPM.

This patch introduces '-m' or '--tpm_mode' flag, which either
enables or disables TPM.

(chroot) gsctool -m enable
open_device 18d1:5014
found interface 3 endpoint 4, chunk_len 64
READY
-------

(chroot) gsctool --tpm_mode disable
open_device 18d1:5014
found interface 3 endpoint 4, chunk_len 64
READY
-------

BUG=b:77543596
BRANCH=gsctool
TEST=manually

Signed-off-by: Namyoon Woo <namyoon@google.com>

Change-Id: I2feb8c51d4343a49f2f5d43291c304e3ad140057
Reviewed-on: https://chromium-review.googlesource.com/1106295
Commit-Ready: Namyoon Woo <namyoon@chromium.org>
Tested-by: Namyoon Woo <namyoon@chromium.org>
Reviewed-by: Namyoon Woo <namyoon@chromium.org>

2 files changed, 73 insertions, 1 deletions

diff --git a/extra/usb_updater/gsctool.c b/extra/usb_updater/gsctool.c
index 1ba93ddd9b..a8fa5102c9 100644
--- a/extra/usb_updater/gsctool.c
+++ b/extra/usb_updater/gsctool.c
@@ -28,6 +28,7 @@
 #include "gsctool.h"
 #include "misc_util.h"
 #include "signed_header.h"
+#include "tpm_registers.h"
 #include "tpm_vendor_cmds.h"
 #include "upgrade_fw.h"
 #include "usb_descriptor.h"
@@ -196,7 +197,7 @@ struct upgrade_pkt {
 static int verbose_mode;
 static uint32_t protocol_version;
 static char *progname;
-static char *short_opts = "aBbcd:F:fhIikO:oPprstUuVvw";
+static char *short_opts = "aBbcd:F:fhIikmO:oPprstUuVvw";
 static const struct option long_opts[] = {
 	/* name    hasarg *flag val */
 	{"any",		                0,   NULL, 'a'},
@@ -217,6 +218,7 @@ static const struct option long_opts[] = {
 	{"post_reset",	                0,   NULL, 'p'},
 	{"rma_auth",	                2,   NULL, 'r'},
 	{"systemdev",	                0,   NULL, 's'},
+	{"tpm_mode",                    1,   NULL, 'm'},
 	{"trunks_send",	                0,   NULL, 't'},
 	{"verbose",	                0,   NULL, 'V'},
 	{"version",	                0,   NULL, 'v'},
@@ -525,6 +527,8 @@ static void usage(int errs)
 	       "                           ID could be 32 bit hex or 4 "
 	       "character string.\n"
 	       "  -k,--ccd_lock            Lock CCD\n"
+	       "  -m,--tpm_mode [enable|disable]\n"
+	       "                           Change or query tpm_mode\n"
 	       "  -O,--openbox_rma <desc_file>\n"
 	       "                           Verify other device's RO integrity\n"
 	       "                           using information provided in "
@@ -1973,6 +1977,56 @@ static void report_version(void)
 	exit(0);
 }
 
+/*
+ * Either change or query TPM mode value.
+ */
+static int process_tpm_mode(struct transfer_descriptor *td,
+				const char *arg)
+{
+	int rv;
+	size_t command_size;
+	size_t response_size;
+	uint8_t response;
+	uint8_t command_body;
+
+	response_size = sizeof(response);
+	if (!arg) {
+		command_size = 0;
+	} else if (!strcasecmp(arg, "disable")) {
+		command_size = sizeof(command_body);
+		command_body = (uint8_t) TPM_MODE_DISABLED;
+	} else if (!strcasecmp(arg, "enable")) {
+		command_size = sizeof(command_body);
+		command_body = (uint8_t) TPM_MODE_ENABLED;
+	} else {
+		fprintf(stderr, "Invalid tpm mode arg: %s.\n", arg);
+		return update_error;
+	}
+
+	rv = send_vendor_command(td, VENDOR_CC_TPM_MODE,
+				&command_body, command_size,
+				&response, &response_size);
+	if (rv) {
+		fprintf(stderr, "Error %d in setting TPM mode.\n", rv);
+		return update_error;
+	}
+	if (response_size != sizeof(response)) {
+		fprintf(stderr, "Error in the size of response,"
+						" %zu.\n", response_size);
+		return update_error;
+	}
+	if (response >= TPM_MODE_MAX) {
+		fprintf(stderr, "Error in the value of response,"
+						" %d.\n", response);
+		return update_error;
+	}
+
+	printf("TPM Mode: %s (%d)\n", (response == TPM_MODE_DISABLED) ?
+				"disabled" : "enabled", response);
+
+	return rv;
+}
+
 int main(int argc, char *argv[])
 {
 	struct transfer_descriptor td;
@@ -1997,11 +2051,14 @@ int main(int argc, char *argv[])
 	int ccd_info = 0;
 	int wp = 0;
 	int try_all_transfer = 0;
+	int tpm_mode = 0;
+
 	const char *exclusive_opt_error =
 		"Options -a, -s and -t are mutually exclusive\n";
 	const char *openbox_desc_file = NULL;
 	int factory_mode = 0;
 	char *factory_mode_arg;
+	char *tpm_mode_arg = NULL;
 
 	progname = strrchr(argv[0], '/');
 	if (progname)
@@ -2073,6 +2130,13 @@ int main(int argc, char *argv[])
 		case 'k':
 			ccd_lock = 1;
 			break;
+		case 'm':
+			tpm_mode = 1;
+			if (!optarg && argv[optind] && argv[optind][0] != '-') {
+				optarg = argv[optind++];
+				tpm_mode_arg = optarg;
+			}
+			break;
 		case 'O':
 			openbox_desc_file = optarg;
 			break;
@@ -2162,6 +2226,7 @@ int main(int argc, char *argv[])
 	    !rma &&
 	    !show_fw_ver &&
 	    !openbox_desc_file &&
+	    !tpm_mode &&
 	    !wp) {
 		if (optind >= argc) {
 			fprintf(stderr,
@@ -2233,6 +2298,12 @@ int main(int argc, char *argv[])
 	if (corrupt_inactive_rw)
 		invalidate_inactive_rw(&td);
 
+	if (tpm_mode) {
+		int rv = process_tpm_mode(&td, tpm_mode_arg);
+
+		exit(rv);
+	}
+
 	if (data || show_fw_ver) {
 
 		setup_connection(&td);
diff --git a/include/tpm_registers.h b/include/tpm_registers.h
index ed03959185..dcdbe41566 100644
--- a/include/tpm_registers.h
+++ b/include/tpm_registers.h
@@ -115,6 +115,7 @@ enum tpm_modes {
 	TPM_MODE_ENABLED_TENTATIVE = 0,
 	TPM_MODE_ENABLED = 1,
 	TPM_MODE_DISABLED = 2,
+	TPM_MODE_MAX,
 };
 
 /*