diff --git a/amd64/hex0.hex0 b/amd64/hex0.hex0 new file mode 100644 index 0000000..c8b4cc5 --- /dev/null +++ b/amd64/hex0.hex0 @@ -0,0 +1,415 @@ +# SPDX-FileCopyrightText: 2022 Andrius Štikonas +# SPDX-FileCopyrightText: 2022 Jeremiah Orians +# +# SPDX-License-Identifier: GPL-3.0-or-later + +# Usage: hex0 file.hex0 file +# Does not validate the arguments or check for success + +# Calling convention: +# First four arguments are passed via registers rcx, rdx, r8, r9 (if they fit in 64-bits) +# but we need to leave stack space +# rax, rcx, rdx, r8, r9, r10 and r11 are volatile and can be changed by called function + +# Registers: +# r12 in/fin: input file name, later reused for handle +# r13 out/fout: output file name, later reused for handle +# r14 system->boot->open_protocol from UEFI, later reused for rootdir +# r15 image_handle from UEFI + +# hex0 algorithm mostly follows stage0-posix version but uses rdi instead of rbp + +# DOS MZ header +4D 5A # Signature +78 00 # Number of bytes in the last page. +01 00 # Number of whole/partial pages +00 00 # Number of entries in the relocation table. +04 00 # Header size +00 00 # Minimum allocation +00 00 # Maximum allocation +00 00 # Relocatable segment address for SS +00 00 # Initial value for SP +00 00 # Checksum (I don't think is looked at) +00 00 # Initial value for IP (Seems ignored) +00 00 # Relocatable segment address for CS (Seems ignored) +40 00 # The (absolute) offset to the relocation table. +00 00 # Value used for overlay management. If zero, this is the main executable +00 00 00 00 00 00 00 00 # Reserved in PE +00 00 # OEM identifier +00 00 # OEM info +00 00 00 00 00 00 00 00 00 00 # The required reserved 20 bytes of NULLS +00 00 00 00 00 00 00 00 00 00 +40 00 00 00 # Starting address of the PE header + +# [0x80] +# PE header +50 45 00 00 # Signature "PE" +64 86 # Machine +01 00 # number of sections +00 00 00 00 # Timestamp supposedly +00 00 00 00 # PointerToSymbolTable +00 00 00 00 # number of symbols +F0 00 # SizeOfOptionalHeader +22 20 # 'Characteristics' + +# [0x98] +# COFF header bits +0B 02 # Magic PE32+ (64 bit) +00 00 # Linker version +A2 01 00 00 # size of code +00 00 00 00 # sizeOfInitializedData +00 00 00 00 # SizeOfUninitializedData +00 10 00 00 # AddressOfEntryPoint +00 10 00 00 # BaseOfCode +00 00 00 80 01 00 00 00 # ImageBase +01 00 00 00 # SectionAlignment +01 00 00 00 # FileAlignment +06 00 00 00 # OperatingSystemVersion +00 00 00 00 # ImageVersion +06 00 00 00 # SubsystemVersion +00 00 00 00 # Win32VersionValue +00 20 00 00 # SizeOfImage +70 01 00 00 # SizeOfHeaders +00 00 00 00 # CheckSum (isn't used at all) +0A 00 # Subsystem +60 01 # DllCharacteristics +00 00 10 00 # SizeOfStackReserve +00 00 00 00 # SizeOfStackCommit +00 10 00 00 # SizeOfHeapReserve +00 00 00 00 # SizeOfHeapCommit +00 00 10 00 # LoaderFlags +00 00 00 00 # NumberOfRvaAndSizes + +# [0xB8] +# Data directories (has to be 16 entries always 16bytes per entry) +00 00 00 00 # Export Table +00 00 00 00 # Size of Export Table + +00 00 00 00 # Import Table +10 00 00 00 # Size of Import Table + +00 00 00 00 # Resource Table +00 00 00 00 # Size of Resource Table + +00 00 00 00 # Exception Table +00 00 00 00 # Size of Exception Table + +00 00 00 00 # Certificate Table +00 00 00 00 # Size of Certificate Table + +00 00 00 00 # Base Relocation Table +00 00 00 00 # Size of Base Relocation Table + +00 00 00 00 # Debug Table +00 00 00 00 # Size of Debug Table + +00 00 00 00 # Architecture Data Table +00 00 00 00 # Size of Architecture Data Table + +00 00 00 00 # Global Pointer +00 00 00 00 # NULL + +00 00 00 00 # TLS Table +00 00 00 00 # Size of TLS Table + +00 00 00 00 # Load Config Table +00 00 00 00 # Size of Load Config Table + +00 00 00 00 # Bound Import Table +00 00 00 00 # Size of Bound Import Table + +00 00 00 00 # Import Address Table +00 00 00 00 # Size of Import Address Table + +00 00 00 00 # Delay Import Descriptor Table +00 00 00 00 # Size of Delay Import Descriptor Table + +00 00 00 00 # CLR Runtime header table +00 00 00 00 # Size of CLR Runtime Header table + +00 00 00 00 00 00 00 00 # MUST BE NULL + +# no idea what it is yet +00 00 00 00 00 00 00 00 +00 00 00 00 00 00 00 00 + +# [0x148] +# Start of section headers +2E 74 65 78 74 00 00 00 ; Name: ".text" +A2 01 00 00 ; VirtualSize +00 10 00 00 ; VirtualAddress +A2 01 00 00 ; SizeOfRawData +70 01 00 00 ; PointerToRawData +00 00 00 00 ; PointerToRelocations +00 00 00 00 ; PointerToLinenumbers +00 00 ; NumberOfRelocations +00 00 ; NumberOfLinenumbers +20 00 00 60 ; 'Characteristics' + +# [0x170] +# Our actual program +# efi_main(void *image_handle, struct efi_system_table *system) +# :_start + 4889E5 ; COPY_RSP_to_RBP # save stack pointer + 4889CF ; COPY_R15_to_RCX # save image_handle + 4C8B72 60 ; LOAD64_into_R14_from_Address_RDX_Immediate8 !96 # system->boot + 4D8BB6 18010000 ; LOAD64_into_R14_from_Address_R14_Immediate32 %280 # system->boot->open_protocol + + # Open Loaded Image protocol + 50 ; PUSH_RAX # allocate stack for image + 4989E0 ; COPY_R8_to_RSP # arg3 = &image + 488905 6E010000 ; LOADI64_rel_RDX !LOADED_IMAGE_PROTOCOL_8 # EFI_LOADED_IMAGE_PROTOCOL_GUID (last 64 bits) +# [_start+0x1C] + 52 ; PUSH_RDX # push last 64 bits onto stack + 488905 5E010000 ; LOADI64_rel_RDX !LOADED_IMAGE_PROTOCOL # EFI_LOADED_IMAGE_PROTOCOL_GUID (first 64 bits) +# [_start+0x24] + 52 ; PUSH_RDX # push first 64 bits onto stack + 4889E2 ; COPY_RDX_to_RSP # arg2 = &guid + 6A 01 ; PUSH !1 # arg6 = EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL + 6A 00 ; PUSH !0 # arg5 = NULL + 4989E0 ; COPY_R8_to_RSP # arg4 = image_handle + # arg1 = ImageHandle (already set) + 4883EC 20 ; SUBI8_RSP !32 # allocate shadow stack space for UEFI function + 41FFD6 ; CALL_R14 # system->boot->open_protocol(image_handle, &guid, &image, image_handle, 0, EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL) + 488B4424 40 ; LOAD64_into_RAX_from_Address_RSP_Immediate8 !64 # get_image + + # Command line args + 4889C1 ; COPY_RCX_to_RAX # save image + 488B58 38 ; LOAD64_into_RBX_from_Address_RAX_Immediate8 !56 # options = image->load_options + +# :loop_options1 [_start+0x42] # Skip application name + 4883C3 02 ; ADDI8_RBX !2 # ++options + 8A03 ; LOAD8_AL_from_Address_RBX # *options + 3C 20 ; CMPI8_AL !0x20 # if *options != ' ' + 75 F6 ; JNE8 !loop_options1 # then jump + + 4883C3 02 ; ADDI8_RBX !2 # ++options + 4989DC ; COPY_RBX_to_R12 # save input file + +# :loop_options2 [_start+0x53] # Skip argv[1] + 4883C3 02 ; ADDI8_RBX !2 # ++options + 8A03 ; LOAD8_AL_from_Address_RBX # *options + 3C 20 ; CMPI8_AL !0x20 # if *options != ' ' + 75 F6 ; JNE8 !loop_options2 # then jump + + CB03 ; STOREI8_into_Address_RBX # *options = 0; + 4883C3 02 ; ADDI8_RBX !2 # ++options + 4989DD ; COPY_RBX_to_R13 # save output file + + # Get root device [_start+0x66] + 50 ; PUSH_RAX # allocate stack for rootfs + 4989E0 ; COPY_R8_to_RSP # arg3 = &rootfs + 488905 29010000 ; LOADI64_rel_RDX %SIMPLE_FS_PROTOCOL_8 # EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID (last 64 bits) + 52 ; PUSH_RDX # push last 64 bits onto stack + 488905 19010000 ; LOADI64_rel_RDX %SIMPLE_FS_PROTOCOL # EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID (first 64 bits) + 52 ; PUSH_RDX # push first 64 bits onto stack + 4889E2 ; COPY_RDX_to_RSP # arg2 = &guid + 6A 01 ; PUSH !1 # arg6 = EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL + 6A 00 ; PUSH !0 # arg5 = NULL + 4989E0 ; COPY_R8_to_RSP # arg4 = image_handle + 488B49 18 ; LOAD64_into_RCX_from_Address_RCX_Immediate8 !24 # arg1 = root_device = image->device + 4883EC 20 ; SUBI8_RSP !32 # allocate shadow stack space for UEFI function + 41FFD6 ; CALL_R14 # system->boot->open_protocol(root_device, &guid, &rootfs, image_handle, 0, EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL) + 488B4C24 40 ; LOAD64_into_RCX_from_Address_RSP_Immediate8 !64 # get rootfs + + # Get root directory + 52 ; PUSH_RDX # allocate stack for rootdir + 4889E2 ; COPY_RDX_to_RSP # arg2 = &rootdir + 50 ; PUSH_RAX # allocate shadow stack space for UEFI function + 50 ; PUSH_RAX # allocate shadow stack space for UEFI function + FF51 08 ; CALL_RCX_Immediate8 !8 # rootfs->open_volume(rootfs, &rootdir) + 58 ; POP_RAX # deallocate stack + 58 ; POP_RAX # deallocate stack + 415E ; POP_R14 # save &rootdir + + # Open file for writing + 52 ; PUSH_RDX # allocate stack for fout + 4889E2 ; COPY_RDX_to_RSP # arg2 = &fout + 6A 00 ; PUSH !0 # arg5 = 0 + 6A 07 ; PUSH !7 # to get 0x8000000000000003 we set the rightmost 3 bits + 4159 ; POP_R9 # and then do right rotation by 1 + 49D1C9 ; ROR_R9 # arg4 = EFI_FILE_MODE_CREATE| EFI_FILE_MODE_WRITE | EFI_FILE_MODE_READ + 4D89E8 ; COPY_R13_to_R8 # arg3 = out + 4C89F1 ; COPY_R14_to_RCX # arg1 = rootdir + 4883EC 20 ; SUBI8_RSP !32 # allocate shadow stack space for UEFI function + FF51 08 ; CALL_RCX_Immediate8 !8 # rootdir->open() + 4C8B6C24 28 ; LOAD64_into_R13_from_Address_RSP_Immediate8 !40 # get fout + + # Open file for reading + 52 ; PUSH_RDX # allocate stack for fin + 4889E2 ; COPY_RDX_to_RSP # arg2 = &fin + 6A 01 ; PUSH !1 # arg5 = EFI_FILE_READ_ONLY + 6A 01 ; PUSH !1 # prepare to set arg4 to EFI_FILE_MODE_READ + 4159 ; POP_R9 # arg4 = EFI_FILE_MODE_READ + 4D89E0 ; COPY_R12_to_R8 # arg3 = in + 4C89F1 ; COPY_R14_to_RCX # arg1 = rootdir + 4883EC 20 ; SUBI8_RSP !32 # allocate shadow stack space for UEFI function + FF51 08 ; CALL_RCX_Immediate8 !8 # rootdir->open() + 4C8B6424 28 ; LOAD64_into_R12_from_Address_RSP_Immediate8 !40 # get fin + + # Our flag for byte processing + 6A FF ; PUSH !-1 + 5B ; POP_RBX # rbx = -1 + + # temp storage for the sum + 31FF ; XOR_EDI_EDI # rdi = 0 + +# :loop # [_start+0xE1] + # Read a byte + E8 6F000000 ; CALLI32 %read_byte + + # process byte + E8 1C000000 ; CALLI32 %hex + + # deal with -1 values + 85C0 ; TEST_EAX_EAX + 7C F2 ; JL8 !loop + + # deal with toggle + 85DB ; TEST_EBX_EBX # jump if ebx >= 0 + 7D 06 ; JGE8 !print + + # process first byte of pair + 89C7 ; COPY_EAX_to_EDI + 31DB ; XOR_EBX_EBX # rbx = 0 + EB E8 ; JMP8 !loop + +# process second byte of pair +# :print [_start+0xF9] + # update the sum and store in output + C1E5 04 ; SHL_EBP_Immediate8 !4 + 01F8 ; ADD_EAX_EDI + + # flip the toggle + FFCB ; DEC_EBX # rbx = -1 + + E8 39000000 ; CALLI32 %write_byte + + EB DA ; JMP8 !loop + +# :hex [_start+0x107] + # Purge Comment Lines (#) + 3C 23 ; CMPI8_AL !35 + 74 1E ; JE8 !purge_comment + + # Purge Comment Lines (;) + 3C 3B ; CMPI8_AL !59 + 74 1A ; JE8 !purge_comment + + # deal all ascii less than '0' + 3C 30 ; CMPI8_AL !48 + 7C 1F ; JL8 !ascii_other + + # deal with 0-9 + 3C 3A ; CMPI8_AL !58 + 7C 1F ; JL8 !ascii_num + + # deal with all ascii less than 'A' + 3C 41 ; CMPI8_AL !65 + 7C 17 ; JL8 !ascii_other + + # deal with 'A'-'F' + 3C 47 ; CMPI8_AL !71 + 7C 1C ; JL8 !ascii_high + + # deal with all ascii less than 'a' + 3C 61 ; CMPI8_AL !97 + 7C 0F ; JL8 !ascii_other + + #deal with 'a'-'f' + 3C 67 ; CMPI8_AL !103 + 7C 12 ; JL8 !ascii_low + + # The rest that remains needs to be ignored + EB 09 ; JMP8 !ascii_other + +# :purge_comment [_start+0x129] + # Read a byte + E8 27000000 ; CALLI32 %read_byte + + # Loop if not LF + 3C 0A ; CMPI8_AL !10 + 75 F7 ; JNE8 !purge_comment + + # Otherwise return -1 + +# :ascii_other [_start+0x132] + 6A FF ; PUSH !-1 + 58 ; POP_RAX # return = -1 + C3 ; RET + +# :ascii_num [_start+0x136] + 2C 30 ; SUBI8_AL !48 + C3 ; RET + +# :ascii_low [_start+0x139] + 2C 20 ; SUBI8_AL !32 # convert to uppercase + +# :ascii_high [_start+0x13B] + 2C 37 ; SUBI8_AL !55 + C3 ; RET + +# Writes byte stored in al +# :write_byte [_start+0x13E] + 4C89E9 ; COPY_R13_to_RCX # arg1 = fout + 6A 01 ; PUSH !1 # size = 1 + 4889E2 ; COPY_RDX_to_RSP # arg2 = &size + 50 ; PUSH_RAX # allocate stack + 4989E0 ; COPY_R8_to_RSP # arg3 = &output + 50 ; PUSH_RAX # allocate shadow stack space for UEFI function + 50 ; PUSH_RAX # allocate shadow stack space for UEFI function + 50 ; PUSH_RAX # allocate shadow stack space for UEFI function + FF51 28 ; CALL_RCX_Immediate8 !40 # fout->write() + 4883C4 28 ; ADDI8_RSP !40 # deallocate stack + + C3 ; RET # return + +# :read_byte [_start+0x155] + 4C89E1 ; COPY_R12_to_RCX # arg1 = fin + 6A 01 ; PUSH !1 # size = 1 + 4889E2 ; COPY_RDX_to_RSP # arg2 = &size + 56 ; PUSH_RSI # allocate stack + 4989E0 ; COPY_R8_to_RSP # arg3 = &input + 50 ; PUSH_RAX # allocate shadow stack space for UEFI function + 50 ; PUSH_RAX # allocate shadow stack space for UEFI function + 50 ; PUSH_RAX # allocate shadow stack space for UEFI function + FF51 20 ; CALL_RCX_Immediate8 !32 # fin->read() + 58 ; POP_RAX # deallocate stack + 58 ; POP_RAX # deallocate stack + 58 ; POP_RAX # deallocate stack + 58 ; POP_RAX # save input to rax + 5E ; POP_RSI # save size to rsi + + # If the file ended (0 bytes read) terminate + 85F6 ; TEST_ESI_ESI # if size = 0 + 74 01 ; JE8 !terminate # then we are done + + C3 ; RET # return + +# :terminate [_start+0x171] + 53 ; PUSH_RBX # allocate stack + 4C89E1 ; COPY_R12_to_RCX # arg1 = fin + FF51 10 ; CALL_RCX_Immediate8 !16 # fin->close() + 4C89E9 ; COPY_R13_to_RCX # arg1 = fout + FF51 10 ; CALL_RCX_Immediate8 !16 # fout->close() + + 4889EC ; COPY_RBP_to_RSP # restore stack + C3 ; RET # return to UEFI + + +# Protocol GUIDs +# :LOADED_IMAGE_PROTOCOL [_start+0x182] + A1 31 1B 5B ; %0x5b1b31a1 + 62 95 ; @0x9562 + D2 11 ; @0x11d2 +# :LOADED_IMAGE_PROTOCOL_8 [_start+0x18A] + 8E 3F 00 A0 C9 69 72 3B ; !0x8e !0x3f !0 !0xa0 !0xc9 !0x69 !0x72 !0x3b + +# :SIMPLE_FS_PROTOCOL [_start+0x192] + 22 5B 4E 96 ; %0x0964e5b22 + 59 64 ; @0x6459 + D2 11 ; @0x11d2 +# :SIMPLE_FS_PROTOCOL_8 [_start+0x19A] + 8E 39 00 A0 C9 69 72 3B ; !0x8e !0x39 !0 !0xa0 !0xc9 !0x69 !0x72 !0x3b + +# [0x1A2]