vboot_reference: Change flashrom_get_wp signature

Expose more information about WP state from the flashrom_drv WP status
function.

The more detailed WP information is required to properly validate the
system WP configuration.

BUG=b:268574030
TEST=futility update

Signed-off-by: Nikolai Artemiev <nartemiev@google.com>
Change-Id: If79b7d8cc68a0583cbf1f7049ac7a2dec088fdd0
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/4301750
Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>
Tested-by: Edward O'Callaghan <quasisec@chromium.org>
Reviewed-by: Yu-Ping Wu <yupingso@chromium.org>
Commit-Queue: Edward O'Callaghan <quasisec@chromium.org>

6 files changed, 40 insertions, 32 deletions

diff --git a/futility/cmd_gbb_utility.c b/futility/cmd_gbb_utility.c
index db0c04a1..79c14130 100644
--- a/futility/cmd_gbb_utility.c
+++ b/futility/cmd_gbb_utility.c
@@ -440,7 +440,7 @@ static int write_to_flash(struct updater_config *cfg, uint8_t *outbuf,
 			  off_t filesize)
 {
 #ifdef USE_FLASHROM
-	if (is_write_protection_enabled(cfg) == WP_ENABLED) {
+	if (is_write_protection_enabled(cfg)) {
 		ERROR("You must disable write protection before setting flags.\n");
 		return -1;
 	}
diff --git a/futility/updater.c b/futility/updater.c
index 362d5dfc..7f1e215f 100644
--- a/futility/updater.c
+++ b/futility/updater.c
@@ -348,9 +348,7 @@ static int write_optional_firmware(struct updater_config *cfg,
 	 * EC & PD may have different WP settings and we want to write
 	 * only if it is OK.
 	 */
-	if (check_programmer_wp &&
-	    dut_get_property(DUT_PROP_WP_HW, cfg) == WP_ENABLED &&
-	    flashrom_get_wp(image->programmer, -1) == WP_ENABLED) {
+	if (check_programmer_wp && is_write_protection_enabled(cfg)) {
 		ERROR("Target %s is write protected, skip updating.\n",
 		      image->programmer);
 		return 0;
diff --git a/futility/updater_dut.c b/futility/updater_dut.c
index 6cb03727..634fd447 100644
--- a/futility/updater_dut.c
+++ b/futility/updater_dut.c
@@ -107,7 +107,7 @@ static int dut_get_tpm_fwver(struct updater_config *cfg)
 static int dut_get_wp_hw(struct updater_config *cfg)
 {
 	/* wpsw refers to write protection 'switch', not 'software'. */
-	return dut_get_property_int("wpsw_cur", cfg) ? WP_ENABLED : WP_DISABLED;
+	return dut_get_property_int("wpsw_cur", cfg);
 }
 
 static int dut_get_platform_version(struct updater_config *cfg)
@@ -125,7 +125,13 @@ static int dut_get_platform_version(struct updater_config *cfg)
 static int dut_get_wp_sw(struct updater_config *cfg)
 {
 	assert(cfg->image.programmer);
-	return flashrom_get_wp(cfg->image.programmer, -1);
+	bool mode;
+
+	if (flashrom_get_wp(cfg->image.programmer, &mode, NULL, NULL, -1)) {
+		/* Read WP status error */
+		return -1;
+	}
+	return mode;
 }
 
 /* Helper functions to use or configure the DUT properties. */
diff --git a/futility/updater_utils.c b/futility/updater_utils.c
index b04e56ca..03b0378d 100644
--- a/futility/updater_utils.c
+++ b/futility/updater_utils.c
@@ -362,16 +362,9 @@ const struct vb2_gbb_header *find_gbb(const struct firmware_image *image)
  */
 int is_write_protection_enabled(struct updater_config *cfg)
 {
-	/* Default to enabled. */
-	int wp = dut_get_property(DUT_PROP_WP_HW, cfg);
-	if (wp == WP_DISABLED)
-		return wp;
-	/* For error or enabled, check WP SW. */
-	wp = dut_get_property(DUT_PROP_WP_SW, cfg);
-	/* Consider all errors as enabled. */
-	if (wp != WP_DISABLED)
-		return WP_ENABLED;
-	return wp;
+	/* Assume HW/SW WP are enabled if -1 error code is returned */
+	return dut_get_property(DUT_PROP_WP_HW, cfg) &&
+	       dut_get_property(DUT_PROP_WP_SW, cfg);
 }
 
 /*
diff --git a/host/lib/flashrom_drv.c b/host/lib/flashrom_drv.c
index ff31e149..09e7f468 100644
--- a/host/lib/flashrom_drv.c
+++ b/host/lib/flashrom_drv.c
@@ -252,9 +252,10 @@ err_init:
 	return r;
 }
 
-enum wp_state flashrom_get_wp(const char *prog_with_params, int verbosity)
+int flashrom_get_wp(const char *prog_with_params, bool *wp_mode,
+		    uint32_t *wp_start, uint32_t *wp_len, int verbosity)
 {
-	enum wp_state r = WP_ERROR;
+	int ret = -1;
 
 	g_verbose_screen = (verbosity == -1) ? FLASHROM_MSG_INFO : verbosity;
 
@@ -282,10 +283,18 @@ enum wp_state flashrom_get_wp(const char *prog_with_params, int verbosity)
 	if (flashrom_wp_read_cfg(cfg, flashctx) != FLASHROM_WP_OK)
 		goto err_read_cfg;
 
-	if (flashrom_wp_get_mode(cfg) == FLASHROM_WP_MODE_DISABLED)
-		r = WP_DISABLED;
-	else
-		r = WP_ENABLED;
+	/* size_t tmp variables for libflashrom compatibility */
+	size_t tmp_wp_start, tmp_wp_len;
+	flashrom_wp_get_range(&tmp_wp_start, &tmp_wp_len, cfg);
+
+	if (wp_start != NULL)
+		*wp_start = tmp_wp_start;
+	if (wp_start != NULL)
+		*wp_len = tmp_wp_len;
+	if (wp_mode != NULL)
+		*wp_mode = flashrom_wp_get_mode(cfg) != FLASHROM_WP_MODE_DISABLED;
+
+	ret = 0;
 
 err_read_cfg:
 	flashrom_wp_cfg_release(cfg);
@@ -295,10 +304,10 @@ err_cleanup:
 
 err_probe:
 	if (flashrom_programmer_shutdown(prog))
-		r = WP_ERROR;
+		ret = -1;
 
 err_init:
 	free(tmp);
 
-	return r;
+	return ret;
 }
diff --git a/host/lib/include/flashrom.h b/host/lib/include/flashrom.h
index 0c1b3716..5fb7a03c 100644
--- a/host/lib/include/flashrom.h
+++ b/host/lib/include/flashrom.h
@@ -71,18 +71,20 @@ int flashrom_write_image(const struct firmware_image *image,
 			const struct firmware_image *diff_image,
 			int do_verify, int verbosity);
 
-enum wp_state {
-	WP_ERROR = -1,
-	WP_DISABLED = 0,
-	WP_ENABLED,
-};
-
 /**
  * Get wp state using flashrom.
  *
  * @param programmer	The name of the programmer to use for reading the
  *                      writeprotect state.
+ * @param wp_mode       Pointer to a bool to store the WP mode. Will be set to
+ *                      false if WP is disabled, true if WP is enabled.
+ *                      NULL can be passed if not needed.
+ * @param wp_start      Pointer to a uint32_t to store the WP start addr.
+ *                      NULL can be passed if not needed.
+ * @param wp_len        Pointer to a uint32_t to store the WP region length.
+ *                      NULL can be passed if not needed.
  *
- * @return WP_DISABLED, WP_ENABLED, ot a relevant error.
+ * @return 0 on success, or a relevant error.
  */
-enum wp_state flashrom_get_wp(const char *programmer, int verbosity);
+int flashrom_get_wp(const char *programmer, bool *wp_mode,
+		    uint32_t *wp_start, uint32_t *wp_len, int verbosity);