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authorMounir IDRASSI <mounir.idrassi@idrix.fr>2016-05-10 22:34:27 +0200
committerMounir IDRASSI <mounir.idrassi@idrix.fr>2016-05-10 22:34:27 +0200
commit268ef2d8e904db5068dbdc0fdc7ce3940d6452ea (patch)
treeb1afa687c97fbf5e1ba2c92c5a10479ae5f832f5 /src/Boot/Windows/BootSector.asm
parent6d61f06a5348aebe7dbc0bf44d3e2729c20f7fd0 (diff)
parent5f47d8b6f11cdb3c4c2f43e04e5acfc6ffcb3035 (diff)
downloadVeraCrypt-268ef2d8e904db5068dbdc0fdc7ce3940d6452ea.tar.gz
VeraCrypt-268ef2d8e904db5068dbdc0fdc7ce3940d6452ea.zip
Merge pull request #61 from davidfoerster/normalize-line-terminators
Normalize line terminators
Diffstat (limited to 'src/Boot/Windows/BootSector.asm')
-rw-r--r--src/Boot/Windows/BootSector.asm488
1 files changed, 244 insertions, 244 deletions
diff --git a/src/Boot/Windows/BootSector.asm b/src/Boot/Windows/BootSector.asm
index e0049d29..833ff616 100644
--- a/src/Boot/Windows/BootSector.asm
+++ b/src/Boot/Windows/BootSector.asm
@@ -1,244 +1,244 @@
-;
-; Derived from source code of TrueCrypt 7.1a, which is
-; Copyright (c) 2008-2012 TrueCrypt Developers Association and which is governed
-; by the TrueCrypt License 3.0.
-;
-; Modifications and additions to the original source code (contained in this file)
-; and all other portions of this file are Copyright (c) 2013-2016 IDRIX
-; and are governed by the Apache License 2.0 the full text of which is
-; contained in the file License.txt included in VeraCrypt binary and source
-; code distribution packages.
-;
-
-.MODEL tiny
-.386
-_TEXT SEGMENT USE16
-
-INCLUDE BootDefs.i
-
-ORG 7C00h ; Standard boot sector offset
-
-start:
- ; BIOS executes boot sector from 0:7C00 or 7C0:0000 (default CD boot loader address).
- ; Far jump to the next instruction sets IP to the standard offset 7C00.
- db 0EAh ; jmp 0:main
- dw main, 0
-
-loader_name_msg:
- db ' VeraCrypt Boot Loader', 13, 10, 0
-
-main:
- cli
- xor ax, ax
- mov ds, ax
- mov ss, ax
- mov sp, 7C00h
- sti
-
- ; Display boot loader name
- test byte ptr [start + TC_BOOT_SECTOR_USER_CONFIG_OFFSET], TC_BOOT_USER_CFG_FLAG_SILENT_MODE
- jnz skip_loader_name_msg
-
- lea si, loader_name_msg
- call print
-skip_loader_name_msg:
-
- ; Determine boot loader segment
- mov ax, TC_BOOT_LOADER_SEGMENT
-
- ; Check available memory
- cmp word ptr [ds:413h], TC_BOOT_LOADER_SEGMENT / 1024 * 16 + TC_BOOT_MEMORY_REQUIRED
- jge memory_ok
-
- mov ax, TC_BOOT_LOADER_SEGMENT_LOW
-
- cmp word ptr [ds:413h], TC_BOOT_LOADER_SEGMENT_LOW / 1024 * 16 + TC_BOOT_MEMORY_REQUIRED
- jge memory_ok
-
- ; Insufficient memory
- mov ax, TC_BOOT_LOADER_LOWMEM_SEGMENT
-
-memory_ok:
- mov es, ax
-
- ; Clear BSS section
- xor al, al
- mov di, TC_COM_EXECUTABLE_OFFSET
- mov cx, TC_BOOT_MEMORY_REQUIRED * 1024 - TC_COM_EXECUTABLE_OFFSET - 1
- cld
- rep stosb
-
- mov ax, es
- sub ax, TC_BOOT_LOADER_DECOMPRESSOR_MEMORY_SIZE / 16 ; Decompressor segment
- mov es, ax
-
- ; Load decompressor
- mov cl, TC_BOOT_LOADER_DECOMPRESSOR_START_SECTOR
-retry_backup:
- mov al, TC_BOOT_LOADER_DECOMPRESSOR_SECTOR_COUNT
- mov bx, TC_COM_EXECUTABLE_OFFSET
- call read_sectors
-
- ; Decompressor checksum
- xor ebx, ebx
- mov si, TC_COM_EXECUTABLE_OFFSET
- mov cx, TC_BOOT_LOADER_DECOMPRESSOR_SECTOR_COUNT * TC_LB_SIZE
- call checksum
- push ebx
-
- ; Load compressed boot loader
- mov bx, TC_BOOT_LOADER_COMPRESSED_BUFFER_OFFSET
- mov cl, TC_BOOT_LOADER_START_SECTOR
- mov al, TC_MAX_BOOT_LOADER_SECTOR_COUNT
-
- test backup_loader_used, 1
- jz non_backup
- mov al, TC_BOOT_LOADER_BACKUP_SECTOR_COUNT - TC_BOOT_LOADER_DECOMPRESSOR_SECTOR_COUNT
- mov cl, TC_BOOT_LOADER_START_SECTOR + TC_BOOT_LOADER_BACKUP_SECTOR_COUNT
-
-non_backup:
- call read_sectors
-
- ; Boot loader checksum
- pop ebx
- mov si, TC_BOOT_LOADER_COMPRESSED_BUFFER_OFFSET
- mov cx, word ptr [start + TC_BOOT_SECTOR_LOADER_LENGTH_OFFSET]
- call checksum
-
- ; Verify checksum
- cmp ebx, dword ptr [start + TC_BOOT_SECTOR_LOADER_CHECKSUM_OFFSET]
- je checksum_ok
-
- ; Checksum incorrect - try using backup if available
- test backup_loader_used, 1
- jnz loader_damaged
-
- mov backup_loader_used, 1
- mov cl, TC_BOOT_LOADER_DECOMPRESSOR_START_SECTOR + TC_BOOT_LOADER_BACKUP_SECTOR_COUNT
-
- test TC_BOOT_CFG_FLAG_BACKUP_LOADER_AVAILABLE, byte ptr [start + TC_BOOT_SECTOR_CONFIG_OFFSET]
- jnz retry_backup
-
-loader_damaged:
- lea si, loader_damaged_msg
- call print
- lea si, loader_name_msg
- call print
- jmp $
-checksum_ok:
-
- ; Set up decompressor segment
- mov ax, es
- mov ds, ax
- cli
- mov ss, ax
- mov sp, TC_BOOT_LOADER_DECOMPRESSOR_MEMORY_SIZE
- sti
-
- push dx
-
- ; Decompress boot loader
- mov cx, word ptr [start + TC_BOOT_SECTOR_LOADER_LENGTH_OFFSET]
- sub cx, TC_GZIP_HEADER_SIZE
- push cx ; Compressed data size
- push TC_BOOT_LOADER_COMPRESSED_BUFFER_OFFSET + TC_GZIP_HEADER_SIZE ; Compressed data
- push TC_MAX_BOOT_LOADER_DECOMPRESSED_SIZE ; Output buffer size
- push TC_BOOT_LOADER_DECOMPRESSOR_MEMORY_SIZE + TC_COM_EXECUTABLE_OFFSET ; Output buffer
-
- push cs
- push decompressor_ret
- push es
- push TC_COM_EXECUTABLE_OFFSET
- retf
-decompressor_ret:
-
- add sp, 8
- pop dx
-
- ; Restore boot sector segment
- push cs
- pop ds
-
- ; Check decompression result
- test ax, ax
- jz decompression_ok
-
- lea si, loader_damaged_msg
- call print
- jmp $
-decompression_ok:
-
- ; DH = boot sector flags
- mov dh, byte ptr [start + TC_BOOT_SECTOR_CONFIG_OFFSET]
-
- ; Set up boot loader segment
- mov ax, es
- add ax, TC_BOOT_LOADER_DECOMPRESSOR_MEMORY_SIZE / 16
- mov es, ax
- mov ds, ax
- cli
- mov ss, ax
- mov sp, TC_BOOT_LOADER_STACK_TOP
- sti
-
- ; Execute boot loader
- push es
- push TC_COM_EXECUTABLE_OFFSET
- retf
-
- ; Print string
-print:
- xor bx, bx
- mov ah, 0eh
- cld
-
-@@: lodsb
- test al, al
- jz print_end
-
- int 10h
- jmp @B
-
-print_end:
- ret
-
- ; Read sectors of the first cylinder
-read_sectors:
- mov ch, 0 ; Cylinder
- mov dh, 0 ; Head
- ; DL = drive number passed from BIOS
- mov ah, 2
- int 13h
- jnc read_ok
-
- lea si, disk_error_msg
- call print
-read_ok:
- ret
-
- ; Calculate checksum
-checksum:
- push ds
- push es
- pop ds
- xor eax, eax
- cld
-
-@@: lodsb
- add ebx, eax
- rol ebx, 1
- loop @B
-
- pop ds
- ret
-
-backup_loader_used db 0
-
-disk_error_msg db 'Disk error', 13, 10, 7, 0
-loader_damaged_msg db 7, 'Loader damaged! Repair with Rescue Disk', 0
-
-ORG 7C00h + 510
- dw 0AA55h ; Boot sector signature
-
-_TEXT ENDS
-END start
+;
+; Derived from source code of TrueCrypt 7.1a, which is
+; Copyright (c) 2008-2012 TrueCrypt Developers Association and which is governed
+; by the TrueCrypt License 3.0.
+;
+; Modifications and additions to the original source code (contained in this file)
+; and all other portions of this file are Copyright (c) 2013-2016 IDRIX
+; and are governed by the Apache License 2.0 the full text of which is
+; contained in the file License.txt included in VeraCrypt binary and source
+; code distribution packages.
+;
+
+.MODEL tiny
+.386
+_TEXT SEGMENT USE16
+
+INCLUDE BootDefs.i
+
+ORG 7C00h ; Standard boot sector offset
+
+start:
+ ; BIOS executes boot sector from 0:7C00 or 7C0:0000 (default CD boot loader address).
+ ; Far jump to the next instruction sets IP to the standard offset 7C00.
+ db 0EAh ; jmp 0:main
+ dw main, 0
+
+loader_name_msg:
+ db ' VeraCrypt Boot Loader', 13, 10, 0
+
+main:
+ cli
+ xor ax, ax
+ mov ds, ax
+ mov ss, ax
+ mov sp, 7C00h
+ sti
+
+ ; Display boot loader name
+ test byte ptr [start + TC_BOOT_SECTOR_USER_CONFIG_OFFSET], TC_BOOT_USER_CFG_FLAG_SILENT_MODE
+ jnz skip_loader_name_msg
+
+ lea si, loader_name_msg
+ call print
+skip_loader_name_msg:
+
+ ; Determine boot loader segment
+ mov ax, TC_BOOT_LOADER_SEGMENT
+
+ ; Check available memory
+ cmp word ptr [ds:413h], TC_BOOT_LOADER_SEGMENT / 1024 * 16 + TC_BOOT_MEMORY_REQUIRED
+ jge memory_ok
+
+ mov ax, TC_BOOT_LOADER_SEGMENT_LOW
+
+ cmp word ptr [ds:413h], TC_BOOT_LOADER_SEGMENT_LOW / 1024 * 16 + TC_BOOT_MEMORY_REQUIRED
+ jge memory_ok
+
+ ; Insufficient memory
+ mov ax, TC_BOOT_LOADER_LOWMEM_SEGMENT
+
+memory_ok:
+ mov es, ax
+
+ ; Clear BSS section
+ xor al, al
+ mov di, TC_COM_EXECUTABLE_OFFSET
+ mov cx, TC_BOOT_MEMORY_REQUIRED * 1024 - TC_COM_EXECUTABLE_OFFSET - 1
+ cld
+ rep stosb
+
+ mov ax, es
+ sub ax, TC_BOOT_LOADER_DECOMPRESSOR_MEMORY_SIZE / 16 ; Decompressor segment
+ mov es, ax
+
+ ; Load decompressor
+ mov cl, TC_BOOT_LOADER_DECOMPRESSOR_START_SECTOR
+retry_backup:
+ mov al, TC_BOOT_LOADER_DECOMPRESSOR_SECTOR_COUNT
+ mov bx, TC_COM_EXECUTABLE_OFFSET
+ call read_sectors
+
+ ; Decompressor checksum
+ xor ebx, ebx
+ mov si, TC_COM_EXECUTABLE_OFFSET
+ mov cx, TC_BOOT_LOADER_DECOMPRESSOR_SECTOR_COUNT * TC_LB_SIZE
+ call checksum
+ push ebx
+
+ ; Load compressed boot loader
+ mov bx, TC_BOOT_LOADER_COMPRESSED_BUFFER_OFFSET
+ mov cl, TC_BOOT_LOADER_START_SECTOR
+ mov al, TC_MAX_BOOT_LOADER_SECTOR_COUNT
+
+ test backup_loader_used, 1
+ jz non_backup
+ mov al, TC_BOOT_LOADER_BACKUP_SECTOR_COUNT - TC_BOOT_LOADER_DECOMPRESSOR_SECTOR_COUNT
+ mov cl, TC_BOOT_LOADER_START_SECTOR + TC_BOOT_LOADER_BACKUP_SECTOR_COUNT
+
+non_backup:
+ call read_sectors
+
+ ; Boot loader checksum
+ pop ebx
+ mov si, TC_BOOT_LOADER_COMPRESSED_BUFFER_OFFSET
+ mov cx, word ptr [start + TC_BOOT_SECTOR_LOADER_LENGTH_OFFSET]
+ call checksum
+
+ ; Verify checksum
+ cmp ebx, dword ptr [start + TC_BOOT_SECTOR_LOADER_CHECKSUM_OFFSET]
+ je checksum_ok
+
+ ; Checksum incorrect - try using backup if available
+ test backup_loader_used, 1
+ jnz loader_damaged
+
+ mov backup_loader_used, 1
+ mov cl, TC_BOOT_LOADER_DECOMPRESSOR_START_SECTOR + TC_BOOT_LOADER_BACKUP_SECTOR_COUNT
+
+ test TC_BOOT_CFG_FLAG_BACKUP_LOADER_AVAILABLE, byte ptr [start + TC_BOOT_SECTOR_CONFIG_OFFSET]
+ jnz retry_backup
+
+loader_damaged:
+ lea si, loader_damaged_msg
+ call print
+ lea si, loader_name_msg
+ call print
+ jmp $
+checksum_ok:
+
+ ; Set up decompressor segment
+ mov ax, es
+ mov ds, ax
+ cli
+ mov ss, ax
+ mov sp, TC_BOOT_LOADER_DECOMPRESSOR_MEMORY_SIZE
+ sti
+
+ push dx
+
+ ; Decompress boot loader
+ mov cx, word ptr [start + TC_BOOT_SECTOR_LOADER_LENGTH_OFFSET]
+ sub cx, TC_GZIP_HEADER_SIZE
+ push cx ; Compressed data size
+ push TC_BOOT_LOADER_COMPRESSED_BUFFER_OFFSET + TC_GZIP_HEADER_SIZE ; Compressed data
+ push TC_MAX_BOOT_LOADER_DECOMPRESSED_SIZE ; Output buffer size
+ push TC_BOOT_LOADER_DECOMPRESSOR_MEMORY_SIZE + TC_COM_EXECUTABLE_OFFSET ; Output buffer
+
+ push cs
+ push decompressor_ret
+ push es
+ push TC_COM_EXECUTABLE_OFFSET
+ retf
+decompressor_ret:
+
+ add sp, 8
+ pop dx
+
+ ; Restore boot sector segment
+ push cs
+ pop ds
+
+ ; Check decompression result
+ test ax, ax
+ jz decompression_ok
+
+ lea si, loader_damaged_msg
+ call print
+ jmp $
+decompression_ok:
+
+ ; DH = boot sector flags
+ mov dh, byte ptr [start + TC_BOOT_SECTOR_CONFIG_OFFSET]
+
+ ; Set up boot loader segment
+ mov ax, es
+ add ax, TC_BOOT_LOADER_DECOMPRESSOR_MEMORY_SIZE / 16
+ mov es, ax
+ mov ds, ax
+ cli
+ mov ss, ax
+ mov sp, TC_BOOT_LOADER_STACK_TOP
+ sti
+
+ ; Execute boot loader
+ push es
+ push TC_COM_EXECUTABLE_OFFSET
+ retf
+
+ ; Print string
+print:
+ xor bx, bx
+ mov ah, 0eh
+ cld
+
+@@: lodsb
+ test al, al
+ jz print_end
+
+ int 10h
+ jmp @B
+
+print_end:
+ ret
+
+ ; Read sectors of the first cylinder
+read_sectors:
+ mov ch, 0 ; Cylinder
+ mov dh, 0 ; Head
+ ; DL = drive number passed from BIOS
+ mov ah, 2
+ int 13h
+ jnc read_ok
+
+ lea si, disk_error_msg
+ call print
+read_ok:
+ ret
+
+ ; Calculate checksum
+checksum:
+ push ds
+ push es
+ pop ds
+ xor eax, eax
+ cld
+
+@@: lodsb
+ add ebx, eax
+ rol ebx, 1
+ loop @B
+
+ pop ds
+ ret
+
+backup_loader_used db 0
+
+disk_error_msg db 'Disk error', 13, 10, 7, 0
+loader_damaged_msg db 7, 'Loader damaged! Repair with Rescue Disk', 0
+
+ORG 7C00h + 510
+ dw 0AA55h ; Boot sector signature
+
+_TEXT ENDS
+END start