Magic Bytes
有一些类型的文件,起始的几个字节内容都是固定的,跟据这几个字节的内容就可以判断文件的类型,这几个字节也被称为“魔数”(magic number),比如class文件的魔数就是“CAFEBABE”。
描述 | 扩展名 | Magic Number |
---|---|---|
Adobe Illustrator | .ai | 25 50 44 46 [%PDF] |
Bitmap graphic | .bmp | 42 4D [BM] |
Class File | .class | CA FE BA BE |
JPEG graphic file | .jpg | FF D8 |
JPEG 2000 graphic file | .jp2 | 0000000C6A5020200D0A [....jP..] |
GIF graphic file | .gif | 47 49 46 38 [GIF89] |
TIF graphic file | .tif | 49 49 [II] |
PNG graphic file | .png | 89 50 4E 47 .PNG |
WAV audio file | .wav | 52 49 46 46 RIFF |
ELF Linux EXE | .elf | 7F 45 4C 46 .ELF |
Photoshop Graphics | .psd | 38 42 50 53 [8BPS] |
Windows Meta File | .wmf | D7 CD C6 9A |
MIDI file | .mid | 4D 54 68 64 [MThd] |
Icon file | .ico | 00 00 01 00 |
MP3 file with ID3 identity tag | .mp3 | 49 44 33 [ID3] |
AVI video file | .avi | 52 49 46 46 [RIFF] |
Flash Shockwave | .swf | 46 57 53 [FWS] |
Flash Video | .flv | 46 4C 56 [FLV] |
Mpeg 4 video file | .mp4 | 00 00 00 18 66 74 79 70 6D 70 34 32 [....ftypmp42] |
MOV video file | .mov | 6D 6F 6F 76 [....moov] |
Windows Video file | .wmv | 30 26 B2 75 8E 66 CF |
Windows Audio file | .wma | 30 26 B2 75 8E 66 CF |
PKZip | .zip | 50 4B 03 04 [PK] |
GZip | .gz | 1F 8B 08 |
Tar file | .tar | 75 73 74 61 72 |
Microsoft Installer | .msi | D0 CF 11 E0 A1 B1 1A E1 |
Object Code File | .obj | 4C 01 |
Dynamic Library | .dll | 4D 5A [MZ] |
CAB Installer file | .cab | 4D 53 43 46 [MSCF] |
Executable file | .exe | 4D 5A [MZ] |
RAR file | .rar | 52 61 72 21 1A 07 00 [Rar!...] |
SYS file | .sys | 4D 5A [MZ] |
Help file | .hlp | 3F 5F 03 00 [?_..] |
VMWare Disk file | .vmdk | 4B 44 4D 56 [KDMV] |
Outlook Post Office file | .pst | 21 42 44 4E 42 [!BDNB] |
PDF Document | 25 50 44 46 [%PDF] | |
Word Document | .doc | D0 CF 11 E0 A1 B1 1A E1 |
RTF Document | .rtf | 7B 5C 72 74 66 31 [{ tf1] |
Excel Document | .xls | D0 CF 11 E0 A1 B1 1A E1 |
PowerPoint Document | .ppt | D0 CF 11 E0 A1 B1 1A E1 |
Visio Document | .vsd | D0 CF 11 E0 A1 B1 1A E1 |
DOCX (Office 2010) | .docx | 50 4B 03 04 [PK] |
XLSX (Office 2010) | .xlsx | 50 4B 03 04 [PK] |
PPTX (Office 2010) | .pptx | 50 4B 03 04 [PK] |
Microsoft Database | .mdb | 53 74 61 6E 64 61 72 64 20 4A 65 74 |
Postcript File | .ps | 25 21 [%!] |
Outlook Message File | .msg | D0 CF 11 E0 A1 B1 1A E1 |
EPS File | .eps | 25 21 50 53 2D 41 64 6F 62 65 2D 33 2E 30 20 45 50 53 46 2D 33 20 30 |
Jar File | .jar | 50 4B 03 04 14 00 08 00 08 00 |
SLN File | .sln | 4D 69 63 72 6F 73 6F 66 74 20 56 69 73 75 61 6C 20 53 74 75 64 69 6F 20 53 6F 6C 75 74 69 6F 6E 20 46 69 6C 65 |
Zlib File | .zlib | 78 9C |
SDF File | .sdf | 78 9C |
使用 php 获取 magic bytes
function magic_bytes($path, $position = 0, $bytes = 4)
{
if (!file_exists($path)) {
return null;
}
$handle = fopen($path, 'rb');
fseek($handle, $position);
$bytes = bin2hex(fread($handle, $bytes));
fclose($handle);
return $bytes;
}
使用 java 获取 magic bytes
public static String getMagicBytes(String filePath, int position, int bytes) {
try {
byte[] data = Files.readAllBytes(Paths.get(filePath));
ByteBuffer bb = ByteBuffer.wrap(data);
bb.position(position);
StringBuilder sb = new StringBuilder();
for(int i=0; i<bytes; i++) {
sb.append(String.format("%02x", bb.get()));
}
return sb.toString();
}catch(IOException ex) {
ex.printStackTrace();
return null;
}
}
使用 python3 获取 magic bytes
def get_magic_bytes(file_path, position=0, nbytes=4):
try:
with open(file_path, 'rb') as file:
file.seek(position)
magic_bytes = file.read(nbytes)
return magic_bytes.hex()
except FileNotFoundError:
print(f"File {file_path} not found.")
return None
使用 golang 获取 magic bytes
import (
"fmt"
"os"
)
func getMagicBytes(filePath string, position, nbytes int) (string, error) {
file, err := os.Open(filePath)
if err != nil {
return "", err
}
defer file.Close()
bytes := make([]byte, nbytes)
_, err = file.ReadAt(bytes, int64(position))
if err != nil {
return "", err
}
return fmt.Sprintf("%x", bytes), nil
}
使用 dart 获取 magic bytes
import 'dart:async';
import 'dart:io';
import 'dart:convert';
Future getMagicBytes(String path, [int position = 0, int nbytes = 4]) async {
var file = new File(path);
if (!await file.exists()) {
print("File does not exist.");
return null;
}
RandomAccessFile openedFile = await file.open(mode: FileMode.read);
await openedFile.setPosition(position);
List magicBytes = [];
for (int i = 0; i < nbytes; i++) {
magicBytes.add(await openedFile.readByte());
}
await openedFile.close();
return hex.encode(magicBytes);
}
😉 腾讯云产品特惠热卖,戳我领取!