From 32a961895ed41cd2bb1f9ae00ab0200c4bfb0bf3 Mon Sep 17 00:00:00 2001
From: Leah Rowe <leah@libreboot.org>
Date: Sun, 19 Feb 2023 18:21:43 +0000
Subject: [PATCH 16/18] 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.
---
 util/ifdtool/ifdtool.c | 117 ++++++++++++++++++++++++++++++-----------
 1 file changed, 85 insertions(+), 32 deletions(-)

diff --git a/util/ifdtool/ifdtool.c b/util/ifdtool/ifdtool.c
index 98afa4bbcf..5509721018 100644
--- a/util/ifdtool/ifdtool.c
+++ b/util/ifdtool/ifdtool.c
@@ -1771,6 +1771,7 @@ static void print_usage(const char *name)
 	       "                                         wbg    - Wellsburg\n"
 	       "   -S | --setpchstrap                    Write a PCH strap\n"
 	       "   -V | --newvalue                       The new value to write into PCH strap specified by -S\n"
+	       "   -N | --nuke <region>                  Overwrite the specified region with 0xFF (all ones)\n"
 	       "   -v | --version:                       print the version\n"
 	       "   -h | --help:                          print this help\n\n"
 	       "<region> is one of Descriptor, BIOS, ME, GbE, Platform Data, Secondary BIOS, "
@@ -1778,13 +1779,70 @@ static void print_usage(const char *name)
 	       "\n");
 }
 
+static int                                                                     
+get_region_type_string(const char *region_type_string)                         
+{                                                                              
+	if (region_type_string == NULL)
+		return -1;
+	else 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;
+	else
+		return -1;
+}
+
+static void                                                                    
+nuke(const char *filename, char *image, int size, int region_type)             
+{                                                                              
+       int i;                                                                  
+       region_t region;                                                        
+       const frba_t *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;
 	int mode_dump = 0, mode_extract = 0, mode_inject = 0, mode_spifreq = 0;
 	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;
+	int mode_read = 0, mode_altmedisable = 0, altmedisable = 0, mode_nuke = 0;
 	char *region_type_string = NULL, *region_fname = NULL;
 	const char *layout_fname = NULL;
 	char *new_filename = NULL;
@@ -1815,6 +1873,7 @@ 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}
 	};
 
@@ -1855,35 +1914,8 @@ 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);
 				print_usage(argv[0]);
@@ -2050,6 +2082,22 @@ 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);
@@ -2065,7 +2113,7 @@ int main(int argc, char *argv[])
 
 	if ((mode_dump + mode_layout + mode_extract + mode_inject + mode_setstrap +
 		mode_newlayout + (mode_spifreq | mode_em100 | mode_unlocked |
-		 mode_locked) + mode_altmedisable + mode_validate) > 1) {
+		 mode_locked) + mode_altmedisable + mode_validate + mode_nuke) > 1) {
 		fprintf(stderr, "You may not specify more than one mode.\n\n");
 		print_usage(argv[0]);
 		exit(EXIT_FAILURE);
@@ -2073,7 +2121,8 @@ int main(int argc, char *argv[])
 
 	if ((mode_dump + mode_layout + mode_extract + mode_inject + mode_setstrap +
 	     mode_newlayout + mode_spifreq + mode_em100 + mode_locked +
-	     mode_unlocked + mode_density + mode_altmedisable + mode_validate) == 0) {
+	     mode_unlocked + mode_density + mode_altmedisable + mode_validate +
+	     mode_nuke) == 0) {
 		fprintf(stderr, "You need to specify a mode.\n\n");
 		print_usage(argv[0]);
 		exit(EXIT_FAILURE);
@@ -2171,6 +2220,10 @@ 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) {
 		fpsba_t *fpsba = find_fpsba(image, size);
 		fmsba_t *fmsba = find_fmsba(image, size);
-- 
2.39.2

