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mirror of https://github.com/wader/fq.git synced 2024-11-27 14:14:58 +03:00
fq/format/zip/zip.go
Mattias Wadman 2fc0a71a47 decode: Refactor scalar usage
Move scalar into own package.
Split scalar code into decode related scalar code (that reads etc) and
scalar code that just transform the scalar value.
Use a scalar.Mapper interface instead of just a function.
Make mappers, assert and validat impement the interface.
2021-12-02 17:39:26 +01:00

327 lines
12 KiB
Go

package zip
// https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT
// https://opensource.apple.com/source/zip/zip-6/unzip/unzip/proginfo/extra.fld
import (
"bytes"
"compress/flate"
"io"
"github.com/wader/fq/format"
"github.com/wader/fq/format/registry"
"github.com/wader/fq/pkg/decode"
"github.com/wader/fq/pkg/scalar"
)
var probeFormat decode.Group
func init() {
registry.MustRegister(decode.Format{
Name: format.ZIP,
Description: "ZIP archive",
Groups: []string{format.PROBE},
DecodeFn: zipDecode,
Dependencies: []decode.Dependency{
{Names: []string{format.PROBE}, Group: &probeFormat},
},
})
}
const (
compressionMethodNone = 0
compressionMethodShrunk = 1
compressionMethodReducedCompressionFactor1 = 2
compressionMethodReducedCompressionFactor2 = 3
compressionMethodReducedCompressionFactor3 = 4
compressionMethodReducedCompressionFactor4 = 5
compressionMethodImploded = 6
compressionMethodDeflated = 8
compressionMethodEnhancedDeflated = 9
compressionMethodPKWareDCLImploded = 10
compressionMethodBzip2 = 12
compressionMethodLZMA = 14
compressionMethodIBMTERSE = 18
compressionMethodIBMLZ77z = 19
compressionMethodPPMd = 98
)
var compressionMethodMap = scalar.UToSymStr{
compressionMethodNone: "None",
compressionMethodShrunk: "Shrunk",
compressionMethodReducedCompressionFactor1: "ReducedCompressionFactor1",
compressionMethodReducedCompressionFactor2: "ReducedCompressionFactor2",
compressionMethodReducedCompressionFactor3: "ReducedCompressionFactor3",
compressionMethodReducedCompressionFactor4: "ReducedCompressionFactor4",
compressionMethodImploded: "Imploded",
compressionMethodDeflated: "Deflated",
compressionMethodEnhancedDeflated: "EnhancedDeflated",
compressionMethodPKWareDCLImploded: "PKWareDCLImploded",
compressionMethodBzip2: "Bzip2",
compressionMethodLZMA: "LZMA",
compressionMethodIBMTERSE: "IBMTERSE",
compressionMethodIBMLZ77z: "IBMLZ77z",
compressionMethodPPMd: "PPMd",
}
var (
centralDirectorySignature = []byte("PK\x01\x02")
endOfCentralDirectorySignature = []byte("PK\x05\x06")
endOfCentralDirectorySignatureN = 0x06054b50
localFileSignature = []byte("PK\x03\x04")
dataIndicatorSignature = []byte("PK\x07\x08")
)
var headerIDMap = scalar.UToScalar{
0x0001: {Description: "ZIP64 extended information extra field"},
0x0007: {Description: "AV Info"},
0x0009: {Description: "OS/2 extended attributes"},
0x000a: {Description: "NTFS (Win9x/WinNT FileTimes)"},
0x000c: {Description: "OpenVMS"},
0x000d: {Description: "Unix"},
0x000f: {Description: "Patch Descriptor"},
0x0014: {Description: "PKCS#7 Store for X.509 Certificates"},
0x0015: {Description: "X.509 Certificate ID and Signature for individual file"},
0x0016: {Description: "X.509 Certificate ID for Central Directory"},
0x0065: {Description: "IBM S/390 attributes - uncompressed"},
0x0066: {Description: "IBM S/390 attributes - compressed"},
0x07c8: {Description: "Info-ZIP Macintosh (old, J. Lee)"},
0x2605: {Description: "ZipIt Macintosh (first version)"},
0x2705: {Description: "ZipIt Macintosh v 1.3.5 and newer (w/o full filename)"},
0x334d: {Description: "Info-ZIP Macintosh (new, D. Haase's 'Mac3' field )"},
0x4154: {Description: "Tandem NSK"},
0x4341: {Description: "Acorn/SparkFS (David Pilling)"},
0x4453: {Description: "Windows NT security descriptor (binary ACL)"},
0x4704: {Description: "VM/CMS"},
0x470f: {Description: "MVS"},
// "inofficial" in original table
//nolint:misspell
0x4854: {Description: "Theos, old inofficial port"},
0x4b46: {Description: "FWKCS MD5 (see below)"},
0x4c41: {Description: "OS/2 access control list (text ACL)"},
0x4d49: {Description: "Info-ZIP OpenVMS (obsolete)"},
0x4d63: {Description: "Macintosh SmartZIP, by Macro Bambini"},
0x4f4c: {Description: "Xceed original location extra field"},
0x5356: {Description: "AOS/VS (binary ACL)"},
0x5455: {Description: "extended timestamp"},
0x5855: {Description: "Info-ZIP Unix (original; also OS/2, NT, etc.)"},
0x554e: {Description: "Xceed unicode extra field"},
0x6542: {Description: "BeOS (BeBox, PowerMac, etc.)"},
0x6854: {Description: "Theos"},
0x756e: {Description: "ASi Unix"},
0x7855: {Description: "Info-ZIP Unix (new)"},
0x7875: {Description: "UNIX UID/GID"},
0xfb4a: {Description: "SMS/QDOS"},
}
// "MS-DOS uses year values relative to 1980 and 2 second precision."
func fieldMSDOSTime(d *decode.D) {
d.FieldU5("hours")
d.FieldU6("minutes")
d.FieldU5("seconds")
}
func fieldMSDOSDate(d *decode.D) {
d.FieldU7("year")
d.FieldU4("month")
d.FieldU5("day")
}
func zipDecode(d *decode.D, in interface{}) interface{} {
// TODO: just decode instead?
if !bytes.Equal(d.PeekBytes(4), []byte("PK\x03\x04")) {
d.Errorf("expected PK header")
}
d.Endian = decode.LittleEndian
d.SeekAbs(d.Len())
// TODO: better EOCD probe
p, _, err := d.TryPeekFind(32, -8, -10000, func(v uint64) bool {
return v == uint64(endOfCentralDirectorySignatureN)
})
if err != nil {
d.Fatalf("can't find end of central directory")
}
d.SeekAbs(d.Len() + p)
var offsetCD uint64
var sizeCD uint64
var diskNr uint64
d.FieldStruct("end_of_central_directory", func(d *decode.D) {
d.FieldRawLen("signature", 4*8, d.ValidateBitBuf(endOfCentralDirectorySignature))
diskNr = d.FieldU16("disk_nr")
d.FieldU16("central_directory_start_disk_nr")
d.FieldU16("nr_of_central_directory_records_on_disk")
d.FieldU16("nr_of_central_directory_records")
sizeCD = d.FieldU32("size_of_central directory")
offsetCD = d.FieldU32("offset_of_start_of_central_directory")
commentLength := d.FieldU16("comment_length")
d.FieldUTF8("comment", int(commentLength))
})
var localFileOffsets []uint64
d.SeekAbs(int64(offsetCD) * 8)
d.FieldArray("central_directories", func(d *decode.D) {
d.LenFn(int64(sizeCD)*8, func(d *decode.D) {
for !d.End() {
d.FieldStruct("central_directory", func(d *decode.D) {
d.FieldRawLen("signature", 4*8, d.ValidateBitBuf(centralDirectorySignature))
d.FieldU16("version_made_by")
d.FieldU16("version_needed")
d.FieldStruct("flags", func(d *decode.D) {
// TODO: 16LE, should have some kind of native endian flag reader helper?
d.FieldU1("unused0")
d.FieldBool("strong_encryption")
d.FieldBool("compressed_patched_data")
d.FieldBool("enhanced_deflation")
d.FieldBool("data_descriptor")
d.FieldBool("compression0")
d.FieldBool("compression1")
d.FieldBool("encrypted")
d.FieldU2("reserved0")
d.FieldBool("mask_header_values")
d.FieldBool("reserved1")
d.FieldBool("language_encoding")
d.FieldU3("unused1")
})
d.FieldU16("compression_method", compressionMethodMap)
d.FieldStruct("last_modification_date", fieldMSDOSTime)
d.FieldStruct("last_modification_time", fieldMSDOSDate)
d.FieldU32("crc32_uncompressed", scalar.Hex)
d.FieldU32("compressed_size")
d.FieldU32("uncompressed_size")
fileNameLength := d.FieldU16("file_name_length")
extraFieldLength := d.FieldU16("extra_field_length")
fileCommentLength := d.FieldU16("file_comment_length")
diskNrStart := d.FieldU16("disk_number_where_file_starts")
d.FieldU16("internal_file_attributes")
d.FieldU32("external_file_attributes")
localFileOffset := d.FieldU32("relative_offset_of_local_file_header")
d.FieldUTF8("file_name", int(fileNameLength))
d.FieldArray("extra_fields", func(d *decode.D) {
d.LenFn(int64(extraFieldLength)*8, func(d *decode.D) {
for !d.End() {
d.FieldStruct("extra_field", func(d *decode.D) {
d.FieldU16("header_id", headerIDMap, scalar.Hex)
dataSize := d.FieldU16("data_size")
d.FieldRawLen("data", int64(dataSize)*8)
})
}
})
})
d.FieldUTF8("file_comment", int(fileCommentLength))
if diskNrStart == diskNr {
localFileOffsets = append(localFileOffsets, localFileOffset)
}
})
}
})
})
d.FieldArray("local_files", func(d *decode.D) {
for _, o := range localFileOffsets {
d.SeekAbs(int64(o) * 8)
d.FieldStruct("local_file", func(d *decode.D) {
var hasDataDescriptor bool
d.FieldRawLen("signature", 4*8, d.ValidateBitBuf(localFileSignature))
d.FieldU16("version_needed")
d.FieldStruct("flags", func(d *decode.D) {
// TODO: 16LE, should have some kind of native endian flag reader helper?
d.FieldU1("unused0")
d.FieldBool("strong_encryption")
d.FieldBool("compressed_patched_data")
d.FieldBool("enhanced_deflation")
hasDataDescriptor = d.FieldBool("data_descriptor")
d.FieldBool("compression0")
d.FieldBool("compression1")
d.FieldBool("encrypted")
d.FieldU2("reserved0")
d.FieldBool("mask_header_values")
d.FieldBool("reserved1")
d.FieldBool("language_encoding")
d.FieldU3("unused1")
})
compressionMethod := d.FieldU16("compression_method", compressionMethodMap)
d.FieldStruct("last_modification_date", fieldMSDOSTime)
d.FieldStruct("last_modification_time", fieldMSDOSDate)
d.FieldU32("crc32_uncompressed", scalar.Hex)
compressedSizeBytes := d.FieldU32("compressed_size")
d.FieldU32("uncompressed_size")
fileNameLength := d.FieldU16("file_name_length")
extraFieldLength := d.FieldU16("extra_field_length")
d.FieldUTF8("file_name", int(fileNameLength))
d.FieldArray("extra_fields", func(d *decode.D) {
d.LenFn(int64(extraFieldLength)*8, func(d *decode.D) {
for !d.End() {
d.FieldStruct("extra_field", func(d *decode.D) {
d.FieldU16("header_id", headerIDMap, scalar.Hex)
dataSize := d.FieldU16("data_size")
d.FieldRawLen("data", int64(dataSize)*8)
})
}
})
})
compressedSize := int64(compressedSizeBytes) * 8
compressedStart := d.Pos()
compressedLimit := compressedSize
if compressedLimit == 0 {
compressedLimit = d.BitsLeft()
}
if compressionMethod == compressionMethodNone {
if dv, _, _ := d.TryFieldFormatLen("uncompressed", compressedSize, probeFormat, nil); dv == nil {
d.FieldRawLen("uncompressed", compressedSize)
}
} else {
var rFn func(r io.Reader) io.Reader
switch compressionMethod {
case compressionMethodDeflated:
// *bitio.Buffer implements io.ByteReader so hat deflate don't do own
// buffering and might read more than needed messing up knowing compressed size
rFn = func(r io.Reader) io.Reader { return flate.NewReader(r) }
}
if rFn != nil {
readCompressedSize, uncompressedBB, dv, _, _ := d.TryFieldReaderRangeFormat("uncompressed", d.Pos(), compressedLimit, rFn, probeFormat, nil)
if dv == nil && uncompressedBB != nil {
d.FieldRootBitBuf("uncompressed", uncompressedBB)
}
if compressedSize == 0 {
compressedSize = readCompressedSize
}
d.FieldRawLen("compressed", compressedSize)
} else {
if compressedSize != 0 {
d.FieldRawLen("compressed", compressedSize)
}
}
}
d.SeekAbs(compressedStart + compressedSize)
if hasDataDescriptor {
d.FieldStruct("data_indicator", func(d *decode.D) {
if bytes.Equal(d.PeekBytes(4), dataIndicatorSignature) {
d.FieldRawLen("signature", 4*8, d.ValidateBitBuf(dataIndicatorSignature))
}
d.FieldU32("crc32_uncompressed", scalar.Hex)
d.FieldU32("compressed_size")
d.FieldU32("uncompressed_size")
})
}
})
}
})
return nil
}