From d97018fc490daf106582b0b7885a497cc2daba5a Mon Sep 17 00:00:00 2001
From: Leah Rowe <info@minifree.org>
Date: Sun, 19 Feb 2023 18:21:43 +0000
Subject: [PATCH 05/40] util/ifdtool: add --nuke flag (all 0xFF on region)

When this option is used, the region's contents are overwritten
with all ones (0xFF).

Example:

./ifdtool --nuke gbe coreboot.rom
./ifdtool --nuke bios coreboot.com
./ifdtool --nuke me coreboot.com

Rebased since the last revision update in lbmk.

Signed-off-by: Leah Rowe <leah@libreboot.org>
---
 util/ifdtool/ifdtool.c | 114 ++++++++++++++++++++++++++++++-----------
 1 file changed, 83 insertions(+), 31 deletions(-)

diff --git a/util/ifdtool/ifdtool.c b/util/ifdtool/ifdtool.c
index b21a89c0e1..fc91d4c239 100644
--- a/util/ifdtool/ifdtool.c
+++ b/util/ifdtool/ifdtool.c
@@ -2230,6 +2230,7 @@ static void print_usage(const char *name)
 	       "                                         tgl    - Tiger Lake\n"
 	       "                                         wbg    - Wellsburg\n"
 	       "   -S | --setpchstrap                    Write a PCH strap\n"
+	       "   -N | --nuke <region>                  Overwrite the specified region with 0xFF (all ones)\n"
 	       "   -V | --newvalue                       The new value to write into PCH strap specified by -S\n"
 	       "   -v | --version:                       print the version\n"
 	       "   -h | --help:                          print this help\n\n"
@@ -2238,6 +2239,60 @@ static void print_usage(const char *name)
 	       "\n");
 }
 
+static int
+get_region_type_string(const char *region_type_string)
+{
+       if (!strcasecmp("Descriptor", region_type_string))
+               return 0;
+       else if (!strcasecmp("BIOS", region_type_string))
+               return 1;
+       else if (!strcasecmp("ME", region_type_string))
+               return 2;
+       else if (!strcasecmp("GbE", region_type_string))
+               return 3;
+       else if (!strcasecmp("Platform Data", region_type_string))
+               return 4;
+       else if (!strcasecmp("Device Exp1", region_type_string))
+               return 5;
+       else if (!strcasecmp("Secondary BIOS", region_type_string))
+               return 6;
+       else if (!strcasecmp("Reserved", region_type_string))
+               return 7;
+       else if (!strcasecmp("EC", region_type_string))
+               return 8;
+       else if (!strcasecmp("Device Exp2", region_type_string))
+               return 9;
+       else if (!strcasecmp("IE", region_type_string))
+               return 10;
+       else if (!strcasecmp("10GbE_0", region_type_string))
+               return 11;
+       else if (!strcasecmp("10GbE_1", region_type_string))
+               return 12;
+       else if (!strcasecmp("PTT", region_type_string))
+               return 15;
+       return -1;
+}
+
+static void
+nuke(const char *filename, char *image, int size, int region_type)
+{
+       int i;
+       struct region region;
+       const struct frba *frba = find_frba(image, size);
+       if (!frba)
+               exit(EXIT_FAILURE);
+
+       region = get_region(frba, region_type);
+       if (region.size > 0) {
+               for (i = region.base; i <= region.limit; i++) {
+                       if ((i + 1) > (size))
+                               break;
+                       image[i] = 0xFF;
+               }
+               write_image(filename, image, size);
+       }
+}
+
 int main(int argc, char *argv[])
 {
 	int opt, option_index = 0;
@@ -2245,6 +2300,7 @@ int main(int argc, char *argv[])
 	int mode_em100 = 0, mode_locked = 0, mode_unlocked = 0, mode_validate = 0;
 	int mode_layout = 0, mode_newlayout = 0, mode_density = 0, mode_setstrap = 0;
 	int mode_read = 0, mode_altmedisable = 0, altmedisable = 0, mode_fmap_template = 0;
+	int mode_nuke = 0;
 	int mode_gpr0_disable = 0, mode_gpr0_enable = 0, mode_gpr0_status = 0;
 	char *region_type_string = NULL, *region_fname = NULL, *layout_fname = NULL;
 	char *new_filename = NULL;
@@ -2279,6 +2335,7 @@ int main(int argc, char *argv[])
 		{"validate", 0, NULL, 't'},
 		{"setpchstrap", 1, NULL, 'S'},
 		{"newvalue", 1, NULL, 'V'},
+		{"nuke", 1, NULL, 'N'},
 		{0, 0, 0, 0}
 	};
 
@@ -2328,35 +2385,8 @@ int main(int argc, char *argv[])
 			region_fname++;
 			// Descriptor, BIOS, ME, GbE, Platform
 			// valid type?
-			if (!strcasecmp("Descriptor", region_type_string))
-				region_type = 0;
-			else if (!strcasecmp("BIOS", region_type_string))
-				region_type = 1;
-			else if (!strcasecmp("ME", region_type_string))
-				region_type = 2;
-			else if (!strcasecmp("GbE", region_type_string))
-				region_type = 3;
-			else if (!strcasecmp("Platform Data", region_type_string))
-				region_type = 4;
-			else if (!strcasecmp("Device Exp1", region_type_string))
-				region_type = 5;
-			else if (!strcasecmp("Secondary BIOS", region_type_string))
-				region_type = 6;
-			else if (!strcasecmp("Reserved", region_type_string))
-				region_type = 7;
-			else if (!strcasecmp("EC", region_type_string))
-				region_type = 8;
-			else if (!strcasecmp("Device Exp2", region_type_string))
-				region_type = 9;
-			else if (!strcasecmp("IE", region_type_string))
-				region_type = 10;
-			else if (!strcasecmp("10GbE_0", region_type_string))
-				region_type = 11;
-			else if (!strcasecmp("10GbE_1", region_type_string))
-				region_type = 12;
-			else if (!strcasecmp("PTT", region_type_string))
-				region_type = 15;
-			if (region_type == -1) {
+			if ((region_type =
+			    get_region_type_string(region_type_string)) == -1) {
 				fprintf(stderr, "No such region type: '%s'\n\n",
 					region_type_string);
 				fprintf(stderr, "run '%s -h' for usage\n", argv[0]);
@@ -2533,6 +2563,22 @@ int main(int argc, char *argv[])
 		case 't':
 			mode_validate = 1;
 			break;
+               case 'N':
+                       region_type_string = strdup(optarg);
+                       if (!region_type_string) {
+                               fprintf(stderr, "No region specified\n");
+                               print_usage(argv[0]);
+                               exit(EXIT_FAILURE);
+                       }
+                       if ((region_type =
+                           get_region_type_string(region_type_string)) == -1) {
+                               fprintf(stderr, "No such region type: '%s'\n\n",
+                                       region_type_string);
+                               print_usage(argv[0]);
+                               exit(EXIT_FAILURE);
+                       }
+                       mode_nuke = 1;
+                       break;
 		case 'v':
 			print_version();
 			exit(EXIT_SUCCESS);
@@ -2552,7 +2598,8 @@ int main(int argc, char *argv[])
 	if ((mode_dump + mode_layout + mode_fmap_template + mode_extract + mode_inject +
 			mode_setstrap + mode_newlayout + (mode_spifreq | mode_em100 |
 			mode_unlocked | mode_locked) + mode_altmedisable + mode_validate +
-			(mode_gpr0_disable | mode_gpr0_enable) + mode_gpr0_status) > 1) {
+			(mode_gpr0_disable | mode_gpr0_enable) + mode_gpr0_status +
+			mode_nuke) > 1) {
 		fprintf(stderr, "You may not specify more than one mode.\n\n");
 		fprintf(stderr, "run '%s -h' for usage\n", argv[0]);
 		exit(EXIT_FAILURE);
@@ -2561,7 +2608,8 @@ int main(int argc, char *argv[])
 	if ((mode_dump + mode_layout + mode_fmap_template + mode_extract + mode_inject +
 			mode_setstrap + mode_newlayout + mode_spifreq + mode_em100 +
 			mode_locked + mode_unlocked + mode_density + mode_altmedisable +
-			mode_validate + (mode_gpr0_disable | mode_gpr0_enable) + mode_gpr0_status) == 0) {
+			mode_validate + (mode_gpr0_disable | mode_gpr0_enable) + mode_gpr0_status +
+			mode_nuke) == 0) {
 		fprintf(stderr, "You need to specify a mode.\n\n");
 		fprintf(stderr, "run '%s -h' for usage\n", argv[0]);
 		exit(EXIT_FAILURE);
@@ -2674,6 +2722,10 @@ int main(int argc, char *argv[])
 		write_image(new_filename, image, size);
 	}
 
+	if (mode_nuke) {
+		nuke(new_filename, image, size, region_type);
+	}
+
 	if (mode_altmedisable) {
 		struct fpsba *fpsba = find_fpsba(image, size);
 		struct fmsba *fmsba = find_fmsba(image, size);
-- 
2.47.3

