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patterns/zip: Add zip64 support (#395)

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Co-authored-by: Nik <werwolv98@gmail.com>
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thrasher
2025-05-15 15:22:20 -04:00
committed by GitHub
parent 74e08623f1
commit bd06987e8e
1 changed files with 130 additions and 41 deletions
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171
patterns/zip.hexpat
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@@ -4,20 +4,55 @@
import std.mem;
import std.math;
import std.core;
import type.time;
struct EndOfCentralDirectory {
u32 headerSignature [[comment("EoCD magic"), name("EoCD PK\\5\\6")]];
u16 diskNum [[comment("Number of this disk "), name("Disk Number")]];
u16 diskStart [[comment("Disk where central directory starts "), name("Central Directory Disk Number")]];
u16 CDRCount [[comment("Number of central directory records on this disk"), name("Central Directory Entries")]];
u16 CentralDirectoryRecordCount [[comment("Total number of entries in the central directory"), name("Total Central Directory Entries")]];
u32 CDSize [[comment("Size of central directory (bytes)"), name("Central Directory Size")]];
u32 CDOffset [[comment("Offset of start of central directory, relative to start of archive"), name("Central Directory Offset")]];
u16 commentLength [[color("00000000")]];
char coment[commentLength] [[name("Comment")]];
using CentralDirectoryFileHeader;
struct EOCD64Locator {
u32 headerSignature [[comment("EoCD magic"), name("EoCD PK\\6\\7")]];
u32 cdrDisk [[comment("Disk number containing the end of central directory record"), name("CDR Disk")]];
u64 eocdOffset [[comment("Offset of end of central directory record"), name("End of Central Directory Record Offset")]];
u32 totalDisks [[comment("Total number of disks"), name("Total Disks")]];
};
struct EndOfCentralDirectory {
u32 magic;
if (magic == 0x06064b50) {
u64 eocdSize [[comment("Size of fixed fields + size of variable data - 12"), name("EOCD Size")]];
u16 madeByVersion [[comment("The version of zip this was authored by"), name("Made By Version")]];
u16 versionNeeded [[comment("The minimum supported ZIP version needed to extract the file"), name("Version Needed")]];
u32 diskNum [[comment("number of this disk"), name("Disk Number")]];
u32 diskStart [[comment("Disk where central directory starts "), name("Central Directory Disk Number")]];
u64 CDRCount [[comment("Number of central directory records on this disk"), name("Central Directory Entries")]];
u64 CentralDirectoryRecordCount [[comment("Total number of entries in the central directory"), name("Total Central Directory Entries")]];
u64 CDSize [[comment("Size of central directory (bytes)"), name("Central Directory Size")]];
u64 CDOffset [[comment("Offset of start of central directory, relative to start of archive"), name("Central Directory Offset")]];
char extra[eocdSize - 44] [[comment("zip64 extensible data sector"), name("Extra Data")]];
EOCD64Locator locator [[name("EOCD Locator")]];
char eocd32[20] [[name("EOCD32")]];
u16 commentLength [[color("00000000")]];
char coment[commentLength] [[name("Comment")]];
CentralDirectoryFileHeader centralDirHeaders[CDRCount] @ (CDOffset) [[name("Files")]];
} else if (magic == 0x06054B50) {
u16 diskNum [[comment("Number of this disk "), name("Disk Number")]];
u16 diskStart [[comment("Disk where central directory starts "), name("Central Directory Disk Number")]];
u16 CDRCount [[comment("Number of central directory records on this disk"), name("Central Directory Entries")]];
u16 CentralDirectoryRecordCount [[comment("Total number of entries in the central directory"), name("Total Central Directory Entries")]];
u32 CDSize [[comment("Size of central directory (bytes)"), name("Central Directory Size")]];
u32 CDOffset [[comment("Offset of start of central directory, relative to start of archive"), name("Central Directory Offset")]];
u16 commentLength [[color("00000000")]];
char coment[commentLength] [[name("Comment")]];
if (CDOffset != 0xFFFFFFFF && CentralDirectoryRecordCount != 0xFFFF) {
CentralDirectoryFileHeader centralDirHeaders[CDRCount] @ (CDOffset) [[name("Files")]];
}
} else {
std::error("Invalid EOCD magic!");
}
};
namespace extra {
@@ -59,11 +94,24 @@ namespace extra {
}
};
struct ZIP64_SizeInfo {
u64 uncompressedSize;
u64 compressedSize;
if (parent.TSize > 16){
u64 localHeaderOffset;;
}
if (parent.TSize > 24){
u32 diskStartNumber;
}
};
struct ExtraField {
u16 tag;
u16 TSize;
if (tag == 0x5455) {
if (tag == 0x0001) {
extra::ZIP64_SizeInfo ZIP64_SizeInfo;
} else if (tag == 0x5455) {
// 0x5455 needs parsed with TSize in context to prevent overshoot from mismatched TSize/flags set
UTFlags Flags;
u64 extraEndFromFlags = $ + 4*(Flags.modification_time_set + Flags.access_time_set + Flags.creation_time_set);
@@ -102,39 +150,41 @@ namespace extra {
}
fn find_eocd() {
// If there is no zip comment, which is the common case,
// the end-of-central-directory record will be 22 bytes long
// at the end of the file; check if size-22 has the signature.
if (std::mem::read_unsigned(std::mem::size()-22, 4, std::mem::Endian::Little) == 0x06054B50) {
return std::mem::size()-22;
} else {
// If it's not there, then there's probably a zip comment;
// search the last 64KB of the file for the signature.
u128 offset_search_from = std::math::max(0, std::mem::size()-65536-22);
u128 prev_address;
while(1){
s128 current_address = std::mem::find_sequence_in_range(0, offset_search_from, std::mem::size(), 0x50,0x4B,0x05,0x06);
u128 offset_search_from = std::math::max(0, std::mem::size()-65536);
u128 prev_address;
while(1){
s128 current_address = std::mem::find_sequence_in_range(0, offset_search_from, std::mem::size(), 0x50,0x4B,0x05,0x06);
//Reached EOF and did not find valid eocd.
if (current_address == -1) {
std::error("Could not find EOCD.");
//Reached EOF and did not find valid eocd.
if (current_address == -1) {
std::error("Could not find EOCD.");
}
//Potential eocd found. Create a eocd struct
EndOfCentralDirectory EOCD32 @ current_address;
if (EOCD32.CDOffset == 0xFFFFFFFF || EOCD32.CentralDirectoryRecordCount == 0xFFFF) {
// this is a zip64 file
if (std::mem::read_unsigned(current_address - 20, 4, std::mem::Endian::Little) == 0x07064B50){
EOCD64Locator locator @ current_address - 20;
EndOfCentralDirectory EOCD64 @ locator.eocdOffset;
//If central directory file header is valid, then we know the eocd offset is valid.
if (std::mem::read_unsigned(EOCD64.CDOffset, 4, std::mem::Endian::Little) == 0x2014B50){
return locator.eocdOffset;
}
}
//Potential eocd found. Create a eocd struct
EndOfCentralDirectory EOCD @ current_address;
} else {
//If central directory file header is valid, then we know the eocd offset is valid.
if (std::mem::read_unsigned(EOCD.CDOffset, 4, std::mem::Endian::Little) == 0x2014B50){
if (std::mem::read_unsigned(EOCD32.CDOffset, 4, std::mem::Endian::Little) == 0x2014B50){
return current_address;
}
offset_search_from = current_address + 1;
prev_address = current_address;
}
offset_search_from = current_address + 1;
prev_address = current_address;
}
};
EndOfCentralDirectory fileInfo @ find_eocd() [[name("End of Central Directory Record")]];
enum CompressionMethod : u16 {
None = 0, // The file is stored (no compression)
@@ -181,6 +231,7 @@ bitfield GeneralPurposeBitFlags {
reservedPKWARE_1 : 2;
};
struct LocalFileHeader {
u32 headerSignature [[name("LCF PK\\3\\4")]];
u16 version [[ comment("The minimum supported ZIP specification version needed to extract the file") ]];
@@ -197,12 +248,32 @@ struct LocalFileHeader {
u64 extraEnd = $ + extraFieldLength;
extra::ExtraField extraFields[while (extra::has_extra_field(extraEnd))] [[comment("Extra Fields")]];
padding[extraEnd - $];
u8 data[compressedSize] [[name("File Data")]];
u8 data[get_file_data_size(compressionMethod, compressedSize, uncompressedSize, extraFields)] [[name("File Data")]];
};
union File {
u32 fileOffset [[comment("Offset of local file header, relative to the start of the first disk on which the file occurs.")]];
LocalFileHeader *fileHeader : u32;
fn get_file_data_size(CompressionMethod compressionMethod, u32 compressedSize, u32 uncompressedSize, ref extra::ExtraField extraFields) {
u32 size = 0;
if (compressionMethod == CompressionMethod::None) {
size = uncompressedSize;
} else {
size = compressedSize;
}
if (size != 0xFFFFFFFF) {
return size;
}
u32 extraSize = std::core::member_count(extraFields);
for (u32 i = 0, i < extraSize, i += 1) {
if (extraFields[i].tag == 0x0001) {
if (compressionMethod == CompressionMethod::None) {
return extraFields[i].ZIP64_SizeInfo.uncompressedSize;
} else {
return extraFields[i].ZIP64_SizeInfo.compressedSize;
}
}
}
return 0;
};
struct CentralDirectoryFileHeader {
@@ -222,12 +293,30 @@ struct CentralDirectoryFileHeader {
u16 diskNumber [[comment("Disk number where file starts")]];
u16 internalFileAttributes;
u32 externalFileAttributes;
File file;
u32 localHeaderOffset;
char fileName[fileNameLength];
u64 extraEnd = $ + extraFieldLength;
extra::ExtraField extraFields[while (extra::has_extra_field(extraEnd))] [[comment("Extra Fields")]];
padding[extraEnd - $];
char comment[fileCommentLength] @ extraEnd;
LocalFileHeader localFileHeader @ get_local_header_offset(localHeaderOffset, extraFields) [[name("Local File Header")]];
};
CentralDirectoryFileHeader centralDirHeaders[fileInfo.CDRCount] @ (fileInfo.CDOffset) [[name("Files")]];
fn get_local_header_offset(u32 localHeaderOffset, ref extra::ExtraField extraFields) {
u32 size = 0;
if (localHeaderOffset != 0xFFFFFFFF) {
return localHeaderOffset;
}
u32 extraSize = std::core::member_count(extraFields);
for (u32 i = 0, i < extraSize, i += 1) {
if (extraFields[i].tag == 0x0001) {
return extraFields[i].ZIP64_SizeInfo.localHeaderOffset;
}
}
std::error("No valid local header offset found!");
};
EndOfCentralDirectory fileInfo @ find_eocd() [[name("End of Central Directory Record")]];