gsctool: move common objects and definitions into a .h file

This is a lateral move allowing to share some data structures and
functions previously limited to the gsctool.c scope.

This will allow adding new functionality in a separate .c file, and
further refactor gsctool.c which little by little became quite
unwieldy.

BRANCH=none
BUG=b:73668125
TEST=gsctool utility still works for uploading Cr50 images.

Change-Id: Ib56db3e0b983c53a228a658467a3059abcf2166e
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/933543
Reviewed-by: Randall Spangler <rspangler@chromium.org>
(cherry picked from commit 52b93ce19d00c9a6507c630501904b845a1b6486)
Reviewed-on: https://chromium-review.googlesource.com/1082091
Reviewed-by: Marco Chen <marcochen@chromium.org>
Commit-Queue: Marco Chen <marcochen@chromium.org>
Tested-by: Marco Chen <marcochen@chromium.org>

2 files changed, 126 insertions, 74 deletions

diff --git a/extra/usb_updater/gsctool.c b/extra/usb_updater/gsctool.c
index 399c8fdba0..abbfe5433d 100644
--- a/extra/usb_updater/gsctool.c
+++ b/extra/usb_updater/gsctool.c
@@ -24,6 +24,7 @@
 
 #include "ccd_config.h"
 #include "compile_time_macros.h"
+#include "gsctool.h"
 #include "misc_util.h"
 #include "signed_header.h"
 #include "tpm_vendor_cmds.h"
@@ -158,13 +159,6 @@
 #define SUBCLASS USB_SUBCLASS_GOOGLE_CR50
 #define PROTOCOL USB_PROTOCOL_GOOGLE_CR50_NON_HC_FW_UPDATE
 
-enum exit_values {
-	noop = 0,	  /* All up to date, no update needed. */
-	all_updated = 1,  /* Update completed, reboot required. */
-	rw_updated  = 2,  /* RO was not updated, reboot required. */
-	update_error = 3  /* Something went wrong. */
-};
-
 /*
  * Need to create an entire TPM PDU when upgrading over /dev/tpm0 and need to
  * have space to prepare the entire PDU.
@@ -197,41 +191,6 @@ struct upgrade_pkt {
  */
 #define MAX_BUF_SIZE	500
 
-struct usb_endpoint {
-	struct libusb_device_handle *devh;
-	uint8_t ep_num;
-	int     chunk_len;
-};
-
-struct transfer_descriptor {
-	/*
-	 * Set to true for use in an upstart script. Do not reboot after
-	 * transfer, and do not transfer RW if versions are the same.
-	 *
-	 * When using in development environment it is beneficial to transfer
-	 * RW images with the same version, as they get started based on the
-	 * header timestamp.
-	 */
-	uint32_t upstart_mode;
-
-	/*
-	 * offsets of RO and WR sections available for update (not currently
-	 * active).
-	 */
-	uint32_t ro_offset;
-	uint32_t rw_offset;
-	uint32_t post_reset;
-	enum transfer_type {
-		usb_xfer = 0,
-		dev_xfer = 1,
-		ts_xfer = 2
-	} ep_type;
-	union {
-		struct usb_endpoint uep;
-		int tpm_fd;
-	};
-};
-
 static uint32_t protocol_version;
 static char *progname;
 static char *short_opts = "abcd:fhikoPprstUu";
@@ -1240,12 +1199,12 @@ static int transfer_image(struct transfer_descriptor *td,
 	return num_txed_sections;
 }
 
-static uint32_t send_vendor_command(struct transfer_descriptor *td,
-				uint16_t subcommand,
-				const void *command_body,
-				size_t command_body_size,
-				void *response,
-				size_t *response_size)
+uint32_t send_vendor_command(struct transfer_descriptor *td,
+			     uint16_t subcommand,
+			     const void *command_body,
+			     size_t command_body_size,
+			     void *response,
+			     size_t *response_size)
 {
 	int32_t rv;
 
@@ -1471,18 +1430,6 @@ static int show_headers_versions(const void *image)
 	return 0;
 }
 
-struct board_id {
-	uint32_t type;		/* Board type */
-	uint32_t type_inv;	/* Board type (inverted) */
-	uint32_t flags;		/* Flags */
-};
-
-enum board_id_action {
-	bid_none,
-	bid_get,
-	bid_set
-};
-
 /*
  * The default flag value will allow to run images built for any hardware
  * generation of a particular board ID.
@@ -1619,17 +1566,9 @@ static void process_password(struct transfer_descriptor *td)
 	exit(update_error);
 }
 
-/*
- * This function can be used to retrieve the current PP status from Cr50 and
- * prompt the user when a PP press is required.
- *
- * Physical presence can be required by different gsctool options, for which
- * Cr50 behavior also differs. The 'command' and 'poll_type' parameters are
- * used by Cr50 to tell what the host is polling for.
- */
-static void poll_for_pp(struct transfer_descriptor *td,
-			uint16_t command,
-			uint8_t poll_type)
+void poll_for_pp(struct transfer_descriptor *td,
+		 uint16_t command,
+		 uint8_t poll_type)
 {
 	uint8_t response;
 	uint8_t prev_response;
@@ -1726,9 +1665,9 @@ 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_bid(struct transfer_descriptor *td,
-			enum board_id_action bid_action,
-			struct board_id *bid)
+void process_bid(struct transfer_descriptor *td,
+		 enum board_id_action bid_action,
+		 struct board_id *bid)
 {
 	size_t response_size;
 
diff --git a/extra/usb_updater/gsctool.h b/extra/usb_updater/gsctool.h
new file mode 100644
index 0000000000..23108f7a84
--- /dev/null
+++ b/extra/usb_updater/gsctool.h
@@ -0,0 +1,113 @@
+/*
+ * Copyright 2018 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef __EXTRA_USB_UPDATER_GSCTOOL_H
+#define __EXTRA_USB_UPDATER_GSCTOOL_H
+
+#include <stdint.h>
+#include <sys/types.h>
+
+/* This describes USB endpoint used to communicate with Cr50. */
+struct usb_endpoint {
+	struct libusb_device_handle *devh;
+	uint8_t ep_num;
+	int     chunk_len;
+};
+
+/*
+ * gsctool uses this structure to keep information about the communications
+ * channel used to talk to the Cr50, and about the state of the Cr50 image.
+ */
+struct transfer_descriptor {
+	/*
+	 * Set to true for use in an upstart script. Do not reboot after
+	 * transfer, and do not transfer RW if versions are the same.
+	 *
+	 * When using in development environment it is beneficial to transfer
+	 * RW images with the same version, as they get started based on the
+	 * header timestamp.
+	 */
+	uint32_t upstart_mode;
+
+	/*
+	 * offsets of RO and WR sections available for update (not currently
+	 * active).
+	 */
+	uint32_t ro_offset;
+	uint32_t rw_offset;
+	uint32_t post_reset;
+
+	/* Type of channel used to communicate with Cr50. */
+	enum transfer_type {
+		usb_xfer = 0,  /* usb interface. */
+		dev_xfer = 1,  /* /dev/tpm0 */
+		ts_xfer = 2    /* trunks_send */
+	} ep_type;
+	union {
+		struct usb_endpoint uep;
+		int tpm_fd;
+	};
+};
+
+/*
+ * These are values returned by the gsctool utility, they are interpreted by
+ * the startup files to decide how to proceed (try to update to a new Cr50
+ * image or not).
+ */
+enum exit_values {
+	noop = 0,	  /* All up to date, no update needed. */
+	all_updated = 1,  /* Update completed, reboot required. */
+	rw_updated  = 2,  /* RO was not updated, reboot required. */
+	update_error = 3  /* Something went wrong. */
+};
+
+
+struct board_id {
+	uint32_t type;	    /* Board type */
+	uint32_t type_inv;  /* Board type (inverted) */
+	uint32_t flags;	    /* Flags */
+};
+
+enum board_id_action {
+	bid_none,
+	bid_get,
+	bid_set
+};
+
+/*
+ * This function allows to retrieve or set (if not initialized) board ID of
+ * the H1 chip.
+ */
+void process_bid(struct transfer_descriptor *td,
+		 enum board_id_action bid_action,
+		 struct board_id *bid);
+
+/*
+ * This function can be used to retrieve the current PP status from Cr50 and
+ * prompt the user when a PP press is required.
+ *
+ * Physical presence can be required by different gsctool options, for which
+ * Cr50 behavior also differs. The 'command' and 'poll_type' parameters are
+ * used by Cr50 to tell what the host is polling for.
+ */
+void poll_for_pp(struct transfer_descriptor *td,
+		 uint16_t command,
+		 uint8_t poll_type);
+
+/*
+ * Function used to send vendor command to the Cr50 and receive a response.
+ * Returns the error code from TPM response header, which is set to zero on
+ * success.
+ */
+uint32_t send_vendor_command(struct transfer_descriptor *td,
+			     uint16_t subcommand,
+			     const void *command_body,
+			     size_t command_body_size,
+			     void *response,
+			     size_t *response_size);
+
+
+#endif // __EXTRA_USB_UPDATER_GSCTOOL_H