gsctool: supprot enabling write protection (WP)

This patch makes use of the modification of the vendor command
VENDOR_CC_WP, which allows to enable WP.

BUG=b:153881773
TEST=verified that attempts to enable WP when running the unmodified
     Cr50 image fail with error message "Early Cr50 versions do not
     support setting WP", and that the updated Cr50 image allows to
     enable WP using 'gsctool -a -w enable'

Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Change-Id: Ie28c1c9b171dd6ea2e3edc0ae624f953cb4fa4fe
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2149526
Reviewed-by: Mary Ruthven <mruthven@chromium.org>

1 files changed, 39 insertions, 13 deletions

diff --git a/extra/usb_updater/gsctool.c b/extra/usb_updater/gsctool.c
index a65bd909eb..74c4a1b5fc 100644
--- a/extra/usb_updater/gsctool.c
+++ b/extra/usb_updater/gsctool.c
@@ -321,8 +321,8 @@ static const struct option_container cmd_line_options[] = {
 	 "Enable debug messages"},
 	{{"version", no_argument, NULL, 'v'},
 	 "Report this utility version"},
-	{{"wp", no_argument, NULL, 'w'},
-	 "Get the current wp setting"}
+	{{"wp", optional_argument, NULL, 'w'},
+	 "[enable] Get the current WP setting or enable WP"}
 };
 
 /* Helper to print debug messages when verbose flag is specified. */
@@ -1972,7 +1972,7 @@ static void process_ccd_state(struct transfer_descriptor *td, int ccd_unlock,
 		poll_for_pp(td, VENDOR_CC_CCD, CCDV_PP_POLL_OPEN);
 }
 
-static void process_wp(struct transfer_descriptor *td)
+static void process_wp(struct transfer_descriptor *td, enum wp_options wp)
 {
 	size_t response_size;
 	uint8_t response;
@@ -1982,10 +1982,25 @@ static void process_wp(struct transfer_descriptor *td)
 
 	printf("Getting WP\n");
 
-	rv = send_vendor_command(td, VENDOR_CC_WP, NULL, 0,
-				 &response, &response_size);
+	if (wp == WP_ENABLE) {
+		uint8_t command = WP_ENABLE;
+
+		rv = send_vendor_command(td, VENDOR_CC_WP, &command,
+					 sizeof(command),
+					 &response, &response_size);
+	} else {
+		rv = send_vendor_command(td, VENDOR_CC_WP, NULL, 0,
+					 &response, &response_size);
+	}
+
 	if (rv != VENDOR_RC_SUCCESS) {
-		fprintf(stderr, "Error %d getting write protect\n", rv);
+		fprintf(stderr, "Error %d %sting write protect\n",
+			rv, (wp == WP_ENABLE) ? "set" : "get");
+		if (wp == WP_ENABLE) {
+			fprintf(stderr,
+				"Early Cr50 versions do not support setting WP"
+				"\n");
+		}
 		exit(update_error);
 	}
 	if (response_size != sizeof(response)) {
@@ -2682,7 +2697,7 @@ int main(int argc, char *argv[])
 	int ccd_info = 0;
 	int get_flog = 0;
 	uint32_t prev_log_entry = 0;
-	int wp = 0;
+	enum wp_options wp = WP_NONE;
 	int get_boot_mode = 0;
 	int try_all_transfer = 0;
 	int tpm_mode = 0;
@@ -2720,7 +2735,6 @@ int main(int argc, char *argv[])
 		{ 'U', &ccd_unlock },
 		{ 'u', &td.upstart_mode },
 		{ 'V', &verbose_mode },
-		{ 'w', &wp },
 		{},
 	};
 
@@ -2855,6 +2869,18 @@ int main(int argc, char *argv[])
 		case 'v':
 			report_version();  /* This will call exit(). */
 			break;
+		case 'w':
+			if (!optarg) {
+				wp = WP_CHECK;
+				break;
+			}
+			if (!strcasecmp(optarg, "enable")) {
+				wp = WP_ENABLE;
+				break;
+			}
+			fprintf(stderr, "Illegal wp option \"%s\"\n", optarg);
+			errorcnt++;
+			break;
 		case 0:				/* auto-handled option */
 			break;
 		case '?':
@@ -2908,7 +2934,7 @@ int main(int argc, char *argv[])
 	    !openbox_desc_file &&
 	    !tstamp &&
 	    !tpm_mode &&
-	    !wp) {
+	    (wp == WP_NONE)) {
 		if (optind >= argc) {
 			fprintf(stderr,
 				"\nERROR: Missing required <binary image>\n\n");
@@ -2936,8 +2962,8 @@ int main(int argc, char *argv[])
 
 	if (((bid_action != bid_none) + !!rma + !!password + !!ccd_open +
 	     !!ccd_unlock + !!ccd_lock + !!ccd_info + !!get_flog +
-	     !!get_boot_mode + !!openbox_desc_file + !!factory_mode + !!wp +
-	     !!get_endorsement_seed) > 1) {
+	     !!get_boot_mode + !!openbox_desc_file + !!factory_mode +
+	     (wp != WP_NONE) + !!get_endorsement_seed) > 1) {
 		fprintf(stderr,
 			"ERROR: options"
 			"-e, -F, -g, -I, -i, -k, -L, -O, -o, -P, -r, -U and -w "
@@ -2982,8 +3008,8 @@ int main(int argc, char *argv[])
 
 	if (factory_mode)
 		process_factory_mode(&td, factory_mode_arg);
-	if (wp)
-		process_wp(&td);
+	if (wp != WP_NONE)
+		process_wp(&td, wp);
 
 	if (corrupt_inactive_rw)
 		invalidate_inactive_rw(&td);