[md5sum] Add md5sum.txt creation and runtime UEFI validation

* This allows *runtime* validation of UEFI bootable media, such as Windows
  or Linux installers, which, considering the unreliability of USB flash
  drives, we assert is a a much better proposal than write-time validation
  that utilities like balenaEcther (and to a lesser extent MCT) provide.
* Based on uefi-md5sum (https://github.com/pbatard/uefi-md5sum).
* Unconditionally activated on ISO extraction for GPT targets for now.
  This will be changed to a user selectable option later.

res/md5/readme.txt

@@ -0,0 +1,3 @@
+This directory contains the uefi-md5sum bootloaders added by Rufus for media validation.
+
+See https://github.com/pbatard/uefi-md5sum for details.

src/format.c

@@ -71,6 +71,7 @@ static float format_percent = 0.0f;
 static int task_number = 0, actual_fs_type;
 static unsigned int sec_buf_pos = 0;
 extern const int nb_steps[FS_MAX];
+extern const char* md5sum_name[2];
 extern uint32_t dur_mins, dur_secs;
 extern uint32_t wim_nb_files, wim_proc_files, wim_extra_files;
 extern BOOL force_large_fat32, enable_ntfs_compression, lock_drive, zero_drive, fast_zeroing, enable_file_indexing;
@@ -1035,11 +1036,11 @@ BOOL WritePBR(HANDLE hLogicalVolume)
 		uprintf(using_msg, bt_to_name(), "FAT32");
 		for (i = 0; i < 2; i++) {
 			if (!is_fat_32_fs(fp)) {
-				uprintf("New volume does not have a %s FAT32 boot sector - aborting", i?"secondary":"primary");
+				uprintf("New volume does not have a %s FAT32 boot sector - aborting", i ? "secondary" : "primary");
 				break;
 			}
-			uprintf("Confirmed new volume has a %s FAT32 boot sector", i?"secondary":"primary");
+			uprintf("Confirmed new volume has a %s FAT32 boot sector", i ? "secondary" : "primary");
-			uprintf("Setting %s FAT32 boot sector for boot...", i?"secondary":"primary");
+			uprintf("Setting %s FAT32 boot sector for boot...", i ? "secondary" : "primary");
 			if (boot_type == BT_FREEDOS) {
 				if (!write_fat_32_fd_br(fp, 0)) break;
 			} else if (boot_type == BT_REACTOS) {
@@ -1964,8 +1965,11 @@ DWORD WINAPI FormatThread(void* param)
 				}
 			}
 		}
+
 		UpdateProgress(OP_FINALIZE, -1.0f);
 		PrintInfoDebug(0, MSG_233);
+		if ((boot_type == BT_IMAGE) && (image_path != NULL) && (img_report.is_iso) && (!windows_to_go))
+			UpdateMD5Sum(drive_name, md5sum_name[img_report.has_md5sum ? img_report.has_md5sum - 1 : 0]);
 		if (IsChecked(IDC_EXTENDED_LABEL))
 			SetAutorun(drive_name);
 		// Issue another complete remount before we exit, to ensure we're clean

src/hash.c

@@ -60,6 +60,7 @@
 #endif
 
 #include <stdio.h>
+#include <assert.h>
 #include <stdlib.h>
 #include <string.h>
 #include <inttypes.h>
@@ -103,14 +104,18 @@
 
 /* Globals */
 char hash_str[HASH_MAX][150];
-uint32_t proc_bufnum, hash_count[HASH_MAX] = { MD5_HASHSIZE, SHA1_HASHSIZE, SHA256_HASHSIZE, SHA512_HASHSIZE };
 HANDLE data_ready[HASH_MAX] = { 0 }, thread_ready[HASH_MAX] = { 0 };
 DWORD read_size[NUM_BUFFERS];
-BOOL enable_extra_hashes = FALSE;
+BOOL enable_extra_hashes = FALSE, validate_md5sum = FALSE;
 uint8_t ALIGNED(64) buffer[NUM_BUFFERS][BUFFER_SIZE];
-extern int default_thread_priority;
-uint32_t pe256ssp_size = 0;
 uint8_t* pe256ssp = NULL;
+uint32_t proc_bufnum, hash_count[HASH_MAX] = { MD5_HASHSIZE, SHA1_HASHSIZE, SHA256_HASHSIZE, SHA512_HASHSIZE };
+uint32_t pe256ssp_size = 0;
+uint64_t md5sum_totalbytes;
+StrArray modified_files = { 0 };
+
+extern int default_thread_priority;
+extern const char* efi_bootname[ARCH_MAX];
 
 /*
  * Rotate 32 or 64 bit integers by n bytes.
@@ -2122,6 +2127,137 @@ void PrintRevokedBootloaderInfo(void)
 		uprintf("WARNING: Could not parse this system's SkuSiPolicy.p7b for additional revoked UEFI bootloaders");
 }
 
+/*
+ * Updates the MD5SUMS/md5sum.txt file that some distros (Ubuntu, Mint...)
+ * use to validate the media. Because we may alter some of the validated files
+ * to add persistence and whatnot, we need to alter the MD5 list as a result.
+ * The format of the file is expected to always be "<MD5SUM> <FILE_PATH>" on
+ * individual lines.
+ * This function is also used to finalize the md5sum.txt we create for use with
+ * our uefi-md5sum bootloaders.
+ */
+void UpdateMD5Sum(const char* dest_dir, const char* md5sum_name)
+{
+	BOOL display_header = TRUE;
+	BYTE* res_data;
+	DWORD res_size;
+	HANDLE hFile;
+	intptr_t pos;
+	uint32_t i, j, size, md5_size, new_size;
+	uint8_t sum[MD5_HASHSIZE];
+	char md5_path[64], path1[64], path2[64], *md5_data = NULL, *new_data = NULL, *str_pos;
+	char *d, *s, *p;
+
+	if (!img_report.has_md5sum && !validate_md5sum)
+		goto out;
+
+	static_sprintf(md5_path, "%s\\%s", dest_dir, md5sum_name);
+	md5_size = read_file(md5_path, (uint8_t**)&md5_data);
+	if (md5_size == 0)
+		goto out;
+
+	for (i = 0; i < modified_files.Index; i++) {
+		for (j = 0; j < (uint32_t)strlen(modified_files.String[i]); j++)
+			if (modified_files.String[i][j] == '\\')
+				modified_files.String[i][j] = '/';
+		str_pos = strstr(md5_data, &modified_files.String[i][2]);
+		if (str_pos == NULL)
+			// File is not listed in md5 sums
+			continue;
+		if (display_header) {
+			uprintf("Updating %s:", md5_path);
+			display_header = FALSE;
+		}
+		uprintf("● %s", &modified_files.String[i][2]);
+		pos = str_pos - md5_data;
+		HashFile(HASH_MD5, modified_files.String[i], sum);
+		while ((pos > 0) && (md5_data[pos - 1] != '\n'))
+			pos--;
+		assert(IS_HEXASCII(md5_data[pos]));
+		for (j = 0; j < 16; j++) {
+			md5_data[pos + 2 * j] = ((sum[j] >> 4) < 10) ? ('0' + (sum[j] >> 4)) : ('a' - 0xa + (sum[j] >> 4));
+			md5_data[pos + 2 * j + 1] = ((sum[j] & 15) < 10) ? ('0' + (sum[j] & 15)) : ('a' - 0xa + (sum[j] & 15));
+		}
+	}
+
+	// If we validate md5sum we need to update the original bootloader names and add md5sum_totalbytes
+	if (validate_md5sum) {
+		new_size = md5_size;
+		new_data = malloc(md5_size + 1024);
+		assert(new_data != NULL);
+		if (new_data == NULL)
+			goto out;
+		// Will be nonzero if we created the file, otherwise zero
+		if (md5sum_totalbytes != 0) {
+			snprintf(new_data, md5_size + 1024, "# md5sum_totalbytes = 0x%llx\n", md5sum_totalbytes);
+			new_size += (uint32_t)strlen(new_data);
+			d = &new_data[strlen(new_data)];
+		} else {
+			d = new_data;
+		}
+		s = md5_data;
+		for (p = md5_data; (p = StrStrIA(p, " ./efi/boot/boot")) != NULL; ) {
+			for (i = 1; i < ARRAYSIZE(efi_bootname); i++) {
+				if (p[12 + strlen(efi_bootname[i])] != 0x0a)
+					continue;
+				p[12 + strlen(efi_bootname[i])] = 0;
+				if (lstrcmpiA(&p[12], efi_bootname[i]) == 0) {
+					res_data = (BYTE*)GetResource(hMainInstance, MAKEINTRESOURCEA(IDR_MD5_BOOT + i),
+						_RT_RCDATA, efi_bootname[i], &res_size, FALSE);
+					static_sprintf(path1, "%s\\%s", dest_dir, &p[3]);
+					for (j = 0; j < strlen(path1); j++)
+						if (path1[j] == '/') path1[j] = '\\';
+					static_strcpy(path2, path1);
+					path2[strlen(path2) - 4] = 0;
+					static_strcat(path2, "_original.efi");
+					if (res_data != NULL && MoveFileU(path1, path2)) {
+						uprintf("Renamed: %s → %s", path1, path2);
+						hFile = CreateFileA(path1, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ, NULL,
+							CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
+						if ((hFile == NULL) || (hFile == INVALID_HANDLE_VALUE)) {
+							uprintf("Could not create '%s': %s.", path1, WindowsErrorString());
+							MoveFileU(path2, path1);
+							continue;
+						}
+						if (!WriteFileWithRetry(hFile, res_data, res_size, NULL, WRITE_RETRIES)) {
+							uprintf("Could not write '%s': %s.", path1, WindowsErrorString());
+							safe_closehandle(hFile);
+							MoveFileU(path2, path1);
+							continue;
+						}
+						safe_closehandle(hFile);
+						uprintf("Created: %s (%s)", path1, SizeToHumanReadable(res_size, FALSE, FALSE));
+						size = (uint32_t)(p - s) + 12 + (uint32_t)strlen(efi_bootname[i]) - 4;
+						memcpy(d, s, size);
+						d = &d[size];
+						strcpy(d, "_original.efi\n");
+						new_size += 9;
+						d = &d[14];
+						s = &p[12 + strlen(efi_bootname[i]) + 1];
+						// TODO: Update sources/boot.wim if we modified it
+						// Also, we'll need to keep a copy of the size of boot.wim BEFORE we alter it
+						// so we can adjust md5sum_totalbytes
+					}
+				}
+				p[12 + strlen(efi_bootname[i])] = 0x0a;
+			}
+			p = &p[12];
+		}
+		p = &md5_data[md5_size];
+		memcpy(d, s, p - s);
+		free(md5_data);
+		md5_data = new_data;
+		md5_size = new_size;
+	}
+
+	write_file(md5_path, md5_data, md5_size);
+	free(md5_data);
+
+out:
+	// We no longer need the string array at this stage
+	StrArrayDestroy(&modified_files);
+}
+
 #if defined(_DEBUG) || defined(TEST) || defined(ALPHA)
 /* Convert a lowercase hex string to binary. Returned value must be freed */
 uint8_t* to_bin(const char* str)

src/iso.c

@@ -82,8 +82,10 @@ typedef struct {
 
 RUFUS_IMG_REPORT img_report;
 int64_t iso_blocking_status = -1;
-extern BOOL preserve_timestamps, enable_ntfs_compression;
+extern uint64_t md5sum_totalbytes;
+extern BOOL preserve_timestamps, enable_ntfs_compression, validate_md5sum;
 extern HANDLE format_thread;
+extern StrArray modified_files;
 BOOL enable_iso = TRUE, enable_joliet = TRUE, enable_rockridge = TRUE, has_ldlinux_c32;
 #define ISO_BLOCKING(x) do {x; iso_blocking_status++; } while(0)
 static const char* psz_extract_dir;
@@ -92,7 +94,7 @@ const char* bootmgr_efi_name = "bootmgr.efi";
 static const char* grldr_name = "grldr";
 static const char* ldlinux_name = "ldlinux.sys";
 static const char* ldlinux_c32 = "ldlinux.c32";
-static const char* md5sum_name[] = { "MD5SUMS", "md5sum.txt" };
+const char* md5sum_name[2] = { "md5sum.txt", "MD5SUMS" };
 static const char* casper_dirname = "/casper";
 static const char* proxmox_dirname = "/proxmox";
 const char* efi_dirname = "/efi/boot";
@@ -124,7 +126,8 @@ static const int64_t old_c32_threshold[NB_OLD_C32] = OLD_C32_THRESHOLD;
 static uint8_t joliet_level = 0;
 static uint64_t total_blocks, extra_blocks, nb_blocks, last_nb_blocks;
 static BOOL scan_only = FALSE;
-static StrArray config_path, isolinux_path, modified_path;
+static FILE* fd_md5sum = NULL;
+static StrArray config_path, isolinux_path;
 static char symlinked_syslinux[MAX_PATH];
 
 // Ensure filenames do not contain invalid FAT32 or NTFS characters
@@ -475,66 +478,11 @@ static void fix_config(const char* psz_fullpath, const char* psz_path, const cha
 	}
 
 	if (modified)
-		StrArrayAdd(&modified_path, psz_fullpath, TRUE);
+		StrArrayAdd(&modified_files, psz_fullpath, TRUE);
 
 	free(src);
 }
 
-// This updates the MD5SUMS/md5sum.txt file that some distros (Ubuntu, Mint...)
-// use to validate the media. Because we may alter some of the validated files
-// to add persistence and whatnot, we need to alter the MD5 list as a result.
-// The format of the file is expected to always be "<MD5SUM> <FILE_PATH>" on
-// individual lines.
-static void update_md5sum(void)
-{
-	BOOL display_header = TRUE;
-	intptr_t pos;
-	uint32_t i, j, size, md5_size;
-	uint8_t* buf = NULL, sum[16];
-	char md5_path[64], * md5_data = NULL, * str_pos;
-
-	if (!img_report.has_md5sum)
-		goto out;
-
-	assert(img_report.has_md5sum <= ARRAYSIZE(md5sum_name));
-	if (img_report.has_md5sum > ARRAYSIZE(md5sum_name))
-		goto out;
-
-	static_sprintf(md5_path, "%s\\%s", psz_extract_dir, md5sum_name[img_report.has_md5sum - 1]);
-	md5_size = read_file(md5_path, (uint8_t**)&md5_data);
-	if (md5_size == 0)
-		goto out;
-
-	for (i = 0; i < modified_path.Index; i++) {
-		str_pos = strstr(md5_data, &modified_path.String[i][2]);
-		if (str_pos == NULL)
-			// File is not listed in md5 sums
-			continue;
-		if (display_header) {
-			uprintf("Updating %s:", md5_path);
-			display_header = FALSE;
-		}
-		uprintf("● %s", &modified_path.String[i][2]);
-		pos = str_pos - md5_data;
-		size = read_file(modified_path.String[i], &buf);
-		if (size == 0)
-			continue;
-		HashBuffer(HASH_MD5, buf, size, sum);
-		free(buf);
-		while ((pos > 0) && (md5_data[pos - 1] != '\n'))
-			pos--;
-		for (j = 0; j < 16; j++) {
-			md5_data[pos + 2 * j] = ((sum[j] >> 4) < 10) ? ('0' + (sum[j] >> 4)) : ('a' - 0xa + (sum[j] >> 4));
-			md5_data[pos + 2 * j + 1] = ((sum[j] & 15) < 10) ? ('0' + (sum[j] & 15)) : ('a' - 0xa + (sum[j] & 15));
-		}
-	}
-
-	write_file(md5_path, md5_data, md5_size);
-	free(md5_data);
-
-out:
-	StrArrayDestroy(&modified_path);
-}
 
 static void print_extracted_file(char* psz_fullpath, uint64_t file_length)
 {
@@ -586,9 +534,10 @@ static int udf_extract_files(udf_t *p_udf, udf_dirent_t *p_udf_dirent, const cha
 	HANDLE file_handle = NULL;
 	DWORD buf_size, wr_size, err;
 	EXTRACT_PROPS props;
+	HASH_CONTEXT ctx;
 	BOOL r, is_identical;
 	int length;
-	size_t i, nb;
+	size_t i, j, nb;
 	char tmp[128], *psz_fullpath = NULL, *psz_sanpath = NULL;
 	const char* psz_basename;
 	udf_dirent_t *p_udf_dirent2;
@@ -669,16 +618,22 @@ static int udf_extract_files(udf_t *p_udf, udf_dirent_t *p_udf_dirent, const cha
 				else
 					goto out;
 			} else {
+				if (fd_md5sum != NULL)
+					hash_init[HASH_MD5](&ctx);
 				while (file_length > 0) {
 					if (FormatStatus)
 						goto out;
-					nb = MIN(ISO_BUFFER_SIZE / UDF_BLOCKSIZE, (file_length + UDF_BLOCKSIZE - 1) / UDF_BLOCKSIZE);
+					nb = (size_t)MIN(ISO_BUFFER_SIZE / UDF_BLOCKSIZE, (file_length + UDF_BLOCKSIZE - 1) / UDF_BLOCKSIZE);
 					read = udf_read_block(p_udf_dirent, buf, nb);
 					if (read < 0) {
 						uprintf("  Error reading UDF file %s", &psz_fullpath[strlen(psz_extract_dir)]);
 						goto out;
 					}
 					buf_size = (DWORD)MIN(file_length, read);
+					if (fd_md5sum != NULL) {
+						md5sum_totalbytes += buf_size;
+						hash_write[HASH_MD5](&ctx, buf, buf_size);
+					}
 					ISO_BLOCKING(r = WriteFileWithRetry(file_handle, buf, buf_size, &wr_size, WRITE_RETRIES));
 					if (!r || (wr_size != buf_size)) {
 						uprintf("  Error writing file: %s", r ? "Short write detected" : WindowsErrorString());
@@ -691,6 +646,12 @@ static int udf_extract_files(udf_t *p_udf, udf_dirent_t *p_udf_dirent, const cha
 						last_nb_blocks = nb_blocks;
 					}
 				}
+				if (fd_md5sum != NULL) {
+					hash_final[HASH_MD5](&ctx);
+					for (j = 0; j < MD5_HASHSIZE; j++)
+						fprintf(fd_md5sum, "%02x", ctx.buf[j]);
+					fprintf(fd_md5sum, "  ./%s\n", &psz_fullpath[3]);
+				}
 			}
 			if ((preserve_timestamps) && (!SetFileTime(file_handle, to_filetime(udf_get_attribute_time(p_udf_dirent)),
 				to_filetime(udf_get_access_time(p_udf_dirent)), to_filetime(udf_get_modification_time(p_udf_dirent)))))
@@ -726,6 +687,7 @@ static int iso_extract_files(iso9660_t* p_iso, const char *psz_path)
 	HANDLE file_handle = NULL;
 	DWORD buf_size, wr_size, err;
 	EXTRACT_PROPS props;
+	HASH_CONTEXT ctx;
 	BOOL is_symlink, is_identical, create_file, free_p_statbuf = FALSE;
 	int length, r = 1;
 	char psz_fullpath[MAX_PATH], *psz_basename = NULL, *psz_sanpath = NULL;
@@ -737,7 +699,7 @@ static int iso_extract_files(iso9660_t* p_iso, const char *psz_path)
 	CdioListNode_t* p_entnode;
 	iso9660_stat_t *p_statbuf;
 	CdioISO9660FileList_t* p_entlist = NULL;
-	size_t i, nb;
+	size_t i, j, nb;
 	lsn_t lsn;
 	int64_t file_length;
 
@@ -921,17 +883,24 @@ static int iso_extract_files(iso9660_t* p_iso, const char *psz_path)
 						uprintf("  Error writing file: %s", WindowsErrorString());
 						goto out;
 					}
-				} else for (i = 0; file_length > 0; i += nb) {
+				} else {
+					if (fd_md5sum != NULL)
+						hash_init[HASH_MD5](&ctx);
+					for (i = 0; file_length > 0; i += nb) {
 						if (FormatStatus)
 							goto out;
 						lsn = p_statbuf->lsn + (lsn_t)i;
-					nb = MIN(ISO_BUFFER_SIZE / ISO_BLOCKSIZE, (file_length + ISO_BLOCKSIZE - 1) / ISO_BLOCKSIZE);
+						nb = (size_t)MIN(ISO_BUFFER_SIZE / ISO_BLOCKSIZE, (file_length + ISO_BLOCKSIZE - 1) / ISO_BLOCKSIZE);
 						if (iso9660_iso_seek_read(p_iso, buf, lsn, (long)nb) != (nb * ISO_BLOCKSIZE)) {
 							uprintf("  Error reading ISO9660 file %s at LSN %lu",
 								psz_iso_name, (long unsigned int)lsn);
 							goto out;
 						}
 						buf_size = (DWORD)MIN(file_length, ISO_BUFFER_SIZE);
+						if (fd_md5sum != NULL) {
+							md5sum_totalbytes += buf_size;
+							hash_write[HASH_MD5](&ctx, buf, buf_size);
+						}
 						ISO_BLOCKING(r = WriteFileWithRetry(file_handle, buf, buf_size, &wr_size, WRITE_RETRIES));
 						if (!r || wr_size != buf_size) {
 							uprintf("  Error writing file: %s", r ? "Short write detected" : WindowsErrorString());
@@ -945,6 +914,13 @@ static int iso_extract_files(iso9660_t* p_iso, const char *psz_path)
 							last_nb_blocks = nb_blocks;
 						}
 					}
+					if (fd_md5sum != NULL) {
+						hash_final[HASH_MD5](&ctx);
+						for (j = 0; j < MD5_HASHSIZE; j++)
+							fprintf(fd_md5sum, "%02x", ctx.buf[j]);
+						fprintf(fd_md5sum, "  ./%s\n", &psz_fullpath[3]);
+					}
+				}
 				if (preserve_timestamps) {
 					LPFILETIME ft = to_filetime(mktime(&p_statbuf->tm));
 					if (!SetFileTime(file_handle, ft, ft, ft))
@@ -1098,7 +1074,17 @@ BOOL ExtractISO(const char* src_iso, const char* dest_dir, BOOL scan)
 		last_nb_blocks = 0;
 		iso_blocking_status = 0;
 		symlinked_syslinux[0] = 0;
-		StrArrayCreate(&modified_path, 8);
+		StrArrayCreate(&modified_files, 8);
+		if (validate_md5sum) {
+			md5sum_totalbytes = 0;
+			// If there isn't an already existing md5sum.txt create one
+			if (img_report.has_md5sum != 1) {
+				static_sprintf(path, "%s\\%s", dest_dir, md5sum_name[0]);
+				fd_md5sum = fopenU(path, "wb");
+				if (fd_md5sum == NULL)
+					uprintf("WARNING: Could not create '%s'", md5sum_name[0]);
+			}
+		}
 	}
 
 	// First try to open as UDF - fallback to ISO if it failed
@@ -1397,7 +1383,8 @@ out:
 					uprintf("Could not move %s → %s", path, dst_path, WindowsErrorString());
 			}
 		}
-		update_md5sum();
+		if (fd_md5sum != NULL)
+			fclose(fd_md5sum);
 	}
 	iso9660_close(p_iso);
 	udf_close(p_udf);

src/resource.h

@@ -69,6 +69,13 @@
 #define IDR_LC_RUFUS_LOC                500
 #define IDR_XT_HOGGER                   501
 #define IDR_UEFI_NTFS                   502
+// The following should match the ArchType array values + 600
+#define IDR_MD5_BOOT                    600
+#define IDR_MD5_BOOTIA32                601
+#define IDR_MD5_BOOTX64                 602
+#define IDR_MD5_BOOTARM                 603
+#define IDR_MD5_BOOTAA64                604
+#define IDR_MD5_BOOTRISCV64             607
 #define IDM_SELECT                      901
 #define IDM_DOWNLOAD                    902
 #define IDC_DEVICE                      1001

src/rufus.c

@@ -94,6 +94,7 @@ static char uppercase_select[2][64], uppercase_start[64], uppercase_close[64], u
 
 extern HANDLE update_check_thread, wim_thread;
 extern BOOL enable_iso, enable_joliet, enable_rockridge, enable_extra_hashes, is_bootloader_revoked;
+extern BOOL validate_md5sum;
 extern BYTE* fido_script;
 extern HWND hFidoDlg;
 extern uint8_t* grub2_buf;
@@ -1441,6 +1442,7 @@ static DWORD WINAPI BootCheckThread(LPVOID param)
 
 	syslinux_ldlinux_len[0] = 0; syslinux_ldlinux_len[1] = 0;
 	is_bootloader_revoked = FALSE;
+	validate_md5sum = FALSE;
 	safe_free(grub2_buf);
 
 	if (ComboBox_GetCurSel(hDeviceList) == CB_ERR)
@@ -1567,6 +1569,9 @@ static DWORD WINAPI BootCheckThread(LPVOID param)
 					ShellExecuteA(hMainDialog, "open", SEVENZIP_URL, NULL, NULL, SW_SHOWNORMAL);
 				goto out;
 			}
+			// TODO: Move this option to a user selection
+			validate_md5sum = TRUE;
+			uprintf("Will add runtime UEFI media validation through 'md5sum.txt'");
 		} else if ( ((fs_type == FS_NTFS) && !HAS_WINDOWS(img_report) && !HAS_GRUB(img_report) && 
 					 (!HAS_SYSLINUX(img_report) || (SL_MAJOR(img_report.sl_version) <= 5)))
 				 || ((IS_FAT(fs_type)) && (!HAS_SYSLINUX(img_report)) && (!allow_dual_uefi_bios) && !IS_EFI_BOOTABLE(img_report) &&

src/rufus.h

@@ -625,6 +625,35 @@ typedef struct {
 #define UNATTEND_OFFLINE_SERVICING_MASK     (UNATTEND_OFFLINE_INTERNAL_DRIVES | UNATTEND_FORCE_S_MODE)
 #define UNATTEND_DEFAULT_SELECTION_MASK     (UNATTEND_SECUREBOOT_TPM_MINRAM | UNATTEND_NO_ONLINE_ACCOUNT | UNATTEND_OFFLINE_INTERNAL_DRIVES)
 
+/* Hash tables */
+typedef struct htab_entry {
+	uint32_t used;
+	char* str;
+	void* data;
+} htab_entry;
+typedef struct htab_table {
+	htab_entry* table;
+	uint32_t size;
+	uint32_t filled;
+} htab_table;
+#define HTAB_EMPTY {NULL, 0, 0}
+extern BOOL htab_create(uint32_t nel, htab_table* htab);
+extern void htab_destroy(htab_table* htab);
+extern uint32_t htab_hash(char* str, htab_table* htab);
+
+/* Basic String Array */
+typedef struct {
+	char** String;
+	uint32_t Index;		// Current array size
+	uint32_t Max;		// Maximum array size
+} StrArray;
+extern void StrArrayCreate(StrArray* arr, uint32_t initial_size);
+extern int32_t StrArrayAdd(StrArray* arr, const char* str, BOOL);
+extern int32_t StrArrayFind(StrArray* arr, const char* str);
+extern void StrArrayClear(StrArray* arr);
+extern void StrArrayDestroy(StrArray* arr);
+#define IsStrArrayEmpty(arr) (arr.Index == 0)
+
 /*
  * Globals
  */
@@ -758,6 +787,7 @@ extern HANDLE CreateFileWithTimeout(LPCSTR lpFileName, DWORD dwDesiredAccess, DW
 extern BOOL SetThreadAffinity(DWORD_PTR* thread_affinity, size_t num_threads);
 extern BOOL HashFile(const unsigned type, const char* path, uint8_t* sum);
 extern BOOL PE256File(const char* path, uint8_t* hash);
+extern void UpdateMD5Sum(const char* dest_dir, const char* md5sum_name);
 extern BOOL HashBuffer(const unsigned type, const uint8_t* buf, const size_t len, uint8_t* sum);
 extern BOOL IsFileInDB(const char* path);
 extern int IsBootloaderRevoked(const char* path);
@@ -787,35 +817,6 @@ extern uint32_t ResolveDllAddress(dll_resolver_t* resolver);
 
 DWORD WINAPI HashThread(void* param);
 
-/* Hash tables */
-typedef struct htab_entry {
-	uint32_t used;
-	char* str;
-	void* data;
-} htab_entry;
-typedef struct htab_table {
-	htab_entry *table;
-	uint32_t size;
-	uint32_t filled;
-} htab_table;
-#define HTAB_EMPTY {NULL, 0, 0}
-extern BOOL htab_create(uint32_t nel, htab_table* htab);
-extern void htab_destroy(htab_table* htab);
-extern uint32_t htab_hash(char* str, htab_table* htab);
-
-/* Basic String Array */
-typedef struct {
-	char**   String;
-	uint32_t Index;		// Current array size
-	uint32_t Max;		// Maximum array size
-} StrArray;
-extern void StrArrayCreate(StrArray* arr, uint32_t initial_size);
-extern int32_t StrArrayAdd(StrArray* arr, const char* str, BOOL );
-extern int32_t StrArrayFind(StrArray* arr, const char* str);
-extern void StrArrayClear(StrArray* arr);
-extern void StrArrayDestroy(StrArray* arr);
-#define IsStrArrayEmpty(arr) (arr.Index == 0)
-
 /*
  * typedefs for the function prototypes. Use the something like:
  *   PF_DECL(FormatEx);

src/rufus.rc

@@ -33,7 +33,7 @@ LANGUAGE LANG_NEUTRAL, SUBLANG_NEUTRAL
 IDD_DIALOG DIALOGEX 12, 12, 232, 326
 STYLE DS_SETFONT | DS_MODALFRAME | DS_CENTER | WS_MINIMIZEBOX | WS_POPUP | WS_CAPTION | WS_SYSMENU
 EXSTYLE WS_EX_ACCEPTFILES
-CAPTION "Rufus 4.5.2118"
+CAPTION "Rufus 4.5.2120"
 FONT 9, "Segoe UI Symbol", 400, 0, 0x0
 BEGIN
     LTEXT           "Drive Properties",IDS_DRIVE_PROPERTIES_TXT,8,6,53,12,NOT WS_GROUP
@@ -305,6 +305,11 @@ BEGIN
     "IDR_FD_EGA18_CPX        RCDATA                  ""../res/freedos/EGA18.CPX""\r\n"
     "IDR_XT_HOGGER           RCDATA                  ""../res/hogger/hogger.exe""\r\n"
     "IDR_UEFI_NTFS           RCDATA                  ""../res/uefi/uefi-ntfs.img""\r\n"
+    "IDR_MD5_BOOTIA32        RCDATA                  ""../res/md5/bootia32.efi""\r\n"
+    "IDR_MD5_BOOTX64         RCDATA                  ""../res/md5/bootx64.efi""\r\n"
+    "IDR_MD5_BOOTARM         RCDATA                  ""../res/md5/bootarm.efi""\r\n"
+    "IDR_MD5_BOOTAA64        RCDATA                  ""../res/md5/bootaa64.efi""\r\n"
+    "IDR_MD5_BOOTRISCV64     RCDATA                  ""../res/md5/bootriscv64.efi""\r\n"
     "IDI_LANG_16             RCDATA                  ""../res/icons/lang-16.png""\r\n"
     "IDI_INFO_16             RCDATA                  ""../res/icons/info-16.png""\r\n"
     "IDI_SETTINGS_16         RCDATA                  ""../res/icons/settings-16.png""\r\n"
@@ -392,8 +397,8 @@ END
 //
 
 VS_VERSION_INFO VERSIONINFO
- FILEVERSION 4,5,2118,0
+ FILEVERSION 4,5,2120,0
- PRODUCTVERSION 4,5,2118,0
+ PRODUCTVERSION 4,5,2120,0
  FILEFLAGSMASK 0x3fL
 #ifdef _DEBUG
  FILEFLAGS 0x1L
@@ -411,13 +416,13 @@ BEGIN
             VALUE "Comments", "https://rufus.ie"
             VALUE "CompanyName", "Akeo Consulting"
             VALUE "FileDescription", "Rufus"
-            VALUE "FileVersion", "4.5.2118"
+            VALUE "FileVersion", "4.5.2120"
             VALUE "InternalName", "Rufus"
-            VALUE "LegalCopyright", "© 2011-2024 Pete Batard (GPL v3)"
+            VALUE "LegalCopyright", "<EFBFBD> 2011-2024 Pete Batard (GPL v3)"
             VALUE "LegalTrademarks", "https://www.gnu.org/licenses/gpl-3.0.html"
             VALUE "OriginalFilename", "rufus-4.5.exe"
             VALUE "ProductName", "Rufus"
-            VALUE "ProductVersion", "4.5.2118"
+            VALUE "ProductVersion", "4.5.2120"
         END
     END
     BLOCK "VarFileInfo"
@@ -485,6 +490,11 @@ IDR_FD_EGA17_CPX        RCDATA                  "../res/freedos/EGA17.CPX"
 IDR_FD_EGA18_CPX        RCDATA                  "../res/freedos/EGA18.CPX"
 IDR_XT_HOGGER           RCDATA                  "../res/hogger/hogger.exe"
 IDR_UEFI_NTFS           RCDATA                  "../res/uefi/uefi-ntfs.img"
+IDR_MD5_BOOTIA32        RCDATA                  "../res/md5/bootia32.efi"
+IDR_MD5_BOOTX64         RCDATA                  "../res/md5/bootx64.efi"
+IDR_MD5_BOOTARM         RCDATA                  "../res/md5/bootarm.efi"
+IDR_MD5_BOOTAA64        RCDATA                  "../res/md5/bootaa64.efi"
+IDR_MD5_BOOTRISCV64     RCDATA                  "../res/md5/bootriscv64.efi"
 IDI_LANG_16             RCDATA                  "../res/icons/lang-16.png"
 IDI_INFO_16             RCDATA                  "../res/icons/info-16.png"
 IDI_SETTINGS_16         RCDATA                  "../res/icons/settings-16.png"

src/wue.c

@@ -47,6 +47,9 @@ char *unattend_xml_path = NULL, unattend_username[MAX_USERNAME_LENGTH];
 BOOL is_bootloader_revoked = FALSE;
 
 extern uint32_t wim_nb_files, wim_proc_files, wim_extra_files;
+extern BOOL validate_md5sum;
+extern uint64_t md5sum_totalbytes;
+extern StrArray modified_files;
 
 /// <summary>
 /// Create an installation answer file containing the sections specified by the flags.
@@ -808,6 +811,10 @@ BOOL ApplyWindowsCustomization(char drive_letter, int flags)
 				CloseHandle(CreateFileU(appraiserres_dll_src, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ,
 					NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL));
 				uprintf("Created '%s' placeholder", appraiserres_dll_src);
+				if (validate_md5sum) {
+					md5sum_totalbytes -= _filesizeU(appraiserres_dll_dst);
+					StrArrayAdd(&modified_files, appraiserres_dll_src, TRUE);
+				}
 			}
 		}
 
@@ -815,6 +822,8 @@ BOOL ApplyWindowsCustomization(char drive_letter, int flags)
 		// We only need to mount boot.wim if we have windowsPE data to deal with. If
 		// not, we can just copy our unattend.xml in \sources\$OEM$\$$\Panther\.
 		if (flags & UNATTEND_WINPE_SETUP_MASK) {
+			if (validate_md5sum)
+				md5sum_totalbytes -= _filesizeU(boot_wim_path);
 			uprintf("Mounting '%s[%d]'...", boot_wim_path, wim_index);
 			// Some "unofficial" ISOs have a modified boot.wim that doesn't have Windows Setup at index 2...
 			if (!WimIsValidIndex(boot_wim_path, wim_index)) {
@@ -929,6 +938,10 @@ out:
 	if (mount_path) {
 		uprintf("Unmounting '%s[%d]'...", boot_wim_path, wim_index);
 		WimUnmountImage(boot_wim_path, wim_index, TRUE);
+		if (validate_md5sum) {
+			md5sum_totalbytes += _filesizeU(boot_wim_path);
+			StrArrayAdd(&modified_files, boot_wim_path, TRUE);
+		}
 		UpdateProgressWithInfo(OP_PATCH, MSG_325, PATCH_PROGRESS_TOTAL, PATCH_PROGRESS_TOTAL);
 	}
 	free(mount_path);