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package magic
import (
"bytes"
"encoding/binary"
)
var (
// Odt matches an OpenDocument Text file.
Odt = offset([]byte("mimetypeapplication/vnd.oasis.opendocument.text"), 30)
// Ott matches an OpenDocument Text Template file.
Ott = offset([]byte("mimetypeapplication/vnd.oasis.opendocument.text-template"), 30)
// Ods matches an OpenDocument Spreadsheet file.
Ods = offset([]byte("mimetypeapplication/vnd.oasis.opendocument.spreadsheet"), 30)
// Ots matches an OpenDocument Spreadsheet Template file.
Ots = offset([]byte("mimetypeapplication/vnd.oasis.opendocument.spreadsheet-template"), 30)
// Odp matches an OpenDocument Presentation file.
Odp = offset([]byte("mimetypeapplication/vnd.oasis.opendocument.presentation"), 30)
// Otp matches an OpenDocument Presentation Template file.
Otp = offset([]byte("mimetypeapplication/vnd.oasis.opendocument.presentation-template"), 30)
// Odg matches an OpenDocument Drawing file.
Odg = offset([]byte("mimetypeapplication/vnd.oasis.opendocument.graphics"), 30)
// Otg matches an OpenDocument Drawing Template file.
Otg = offset([]byte("mimetypeapplication/vnd.oasis.opendocument.graphics-template"), 30)
// Odf matches an OpenDocument Formula file.
Odf = offset([]byte("mimetypeapplication/vnd.oasis.opendocument.formula"), 30)
// Odc matches an OpenDocument Chart file.
Odc = offset([]byte("mimetypeapplication/vnd.oasis.opendocument.chart"), 30)
// Epub matches an EPUB file.
Epub = offset([]byte("mimetypeapplication/epub+zip"), 30)
// Sxc matches an OpenOffice Spreadsheet file.
Sxc = offset([]byte("mimetypeapplication/vnd.sun.xml.calc"), 30)
)
// Zip matches a zip archive.
func Zip(raw []byte, limit uint32) bool {
return len(raw) > 3 &&
raw[0] == 0x50 && raw[1] == 0x4B &&
(raw[2] == 0x3 || raw[2] == 0x5 || raw[2] == 0x7) &&
(raw[3] == 0x4 || raw[3] == 0x6 || raw[3] == 0x8)
}
// Jar matches a Java archive file.
func Jar(raw []byte, limit uint32) bool {
return zipContains(raw, []byte("META-INF/MANIFEST.MF"), false)
}
func zipContains(raw, sig []byte, msoCheck bool) bool {
b := readBuf(raw)
pk := []byte("PK\003\004")
if len(b) < 0x1E {
return false
}
if !b.advance(0x1E) {
return false
}
if bytes.HasPrefix(b, sig) {
return true
}
if msoCheck {
skipFiles := [][]byte{
[]byte("[Content_Types].xml"),
[]byte("_rels/.rels"),
[]byte("docProps"),
[]byte("customXml"),
[]byte("[trash]"),
}
hasSkipFile := false
for _, sf := range skipFiles {
if bytes.HasPrefix(b, sf) {
hasSkipFile = true
break
}
}
if !hasSkipFile {
return false
}
}
searchOffset := binary.LittleEndian.Uint32(raw[18:]) + 49
if !b.advance(int(searchOffset)) {
return false
}
nextHeader := bytes.Index(raw[searchOffset:], pk)
if !b.advance(nextHeader) {
return false
}
if bytes.HasPrefix(b, sig) {
return true
}
for i := 0; i < 4; i++ {
if !b.advance(0x1A) {
return false
}
nextHeader = bytes.Index(b, pk)
if nextHeader == -1 {
return false
}
if !b.advance(nextHeader + 0x1E) {
return false
}
if bytes.HasPrefix(b, sig) {
return true
}
}
return false
}
// APK matches an Android Package Archive.
// The source of signatures is https://github.com/file/file/blob/1778642b8ba3d947a779a36fcd81f8e807220a19/magic/Magdir/archive#L1820-L1887
func APK(raw []byte, _ uint32) bool {
apkSignatures := [][]byte{
[]byte("AndroidManifest.xml"),
[]byte("META-INF/com/android/build/gradle/app-metadata.properties"),
[]byte("classes.dex"),
[]byte("resources.arsc"),
[]byte("res/drawable"),
}
for _, sig := range apkSignatures {
if zipContains(raw, sig, false) {
return true
}
}
return false
}
|
