123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559 |
- 'use strict';
- module.exports = input => {
- const buf = new Uint8Array(input);
- if (!(buf && buf.length > 1)) {
- return null;
- }
- const check = (header, opts) => {
- opts = Object.assign({
- offset: 0
- }, opts);
- for (let i = 0; i < header.length; i++) {
- if (header[i] !== buf[i + opts.offset]) {
- return false;
- }
- }
- return true;
- };
- if (check([0xFF, 0xD8, 0xFF])) {
- return {
- ext: 'jpg',
- mime: 'image/jpeg'
- };
- }
- if (check([0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A])) {
- return {
- ext: 'png',
- mime: 'image/png'
- };
- }
- if (check([0x47, 0x49, 0x46])) {
- return {
- ext: 'gif',
- mime: 'image/gif'
- };
- }
- if (check([0x57, 0x45, 0x42, 0x50], {offset: 8})) {
- return {
- ext: 'webp',
- mime: 'image/webp'
- };
- }
- if (check([0x46, 0x4C, 0x49, 0x46])) {
- return {
- ext: 'flif',
- mime: 'image/flif'
- };
- }
- // Needs to be before `tif` check
- if (
- (check([0x49, 0x49, 0x2A, 0x0]) || check([0x4D, 0x4D, 0x0, 0x2A])) &&
- check([0x43, 0x52], {offset: 8})
- ) {
- return {
- ext: 'cr2',
- mime: 'image/x-canon-cr2'
- };
- }
- if (
- check([0x49, 0x49, 0x2A, 0x0]) ||
- check([0x4D, 0x4D, 0x0, 0x2A])
- ) {
- return {
- ext: 'tif',
- mime: 'image/tiff'
- };
- }
- if (check([0x42, 0x4D])) {
- return {
- ext: 'bmp',
- mime: 'image/bmp'
- };
- }
- if (check([0x49, 0x49, 0xBC])) {
- return {
- ext: 'jxr',
- mime: 'image/vnd.ms-photo'
- };
- }
- if (check([0x38, 0x42, 0x50, 0x53])) {
- return {
- ext: 'psd',
- mime: 'image/vnd.adobe.photoshop'
- };
- }
- // Needs to be before the `zip` check
- if (
- check([0x50, 0x4B, 0x3, 0x4]) &&
- check([0x6D, 0x69, 0x6D, 0x65, 0x74, 0x79, 0x70, 0x65, 0x61, 0x70, 0x70, 0x6C, 0x69, 0x63, 0x61, 0x74, 0x69, 0x6F, 0x6E, 0x2F, 0x65, 0x70, 0x75, 0x62, 0x2B, 0x7A, 0x69, 0x70], {offset: 30})
- ) {
- return {
- ext: 'epub',
- mime: 'application/epub+zip'
- };
- }
- // Needs to be before `zip` check
- // Assumes signed `.xpi` from addons.mozilla.org
- if (
- check([0x50, 0x4B, 0x3, 0x4]) &&
- check([0x4D, 0x45, 0x54, 0x41, 0x2D, 0x49, 0x4E, 0x46, 0x2F, 0x6D, 0x6F, 0x7A, 0x69, 0x6C, 0x6C, 0x61, 0x2E, 0x72, 0x73, 0x61], {offset: 30})
- ) {
- return {
- ext: 'xpi',
- mime: 'application/x-xpinstall'
- };
- }
- if (
- check([0x50, 0x4B]) &&
- (buf[2] === 0x3 || buf[2] === 0x5 || buf[2] === 0x7) &&
- (buf[3] === 0x4 || buf[3] === 0x6 || buf[3] === 0x8)
- ) {
- return {
- ext: 'zip',
- mime: 'application/zip'
- };
- }
- if (check([0x75, 0x73, 0x74, 0x61, 0x72], {offset: 257})) {
- return {
- ext: 'tar',
- mime: 'application/x-tar'
- };
- }
- if (
- check([0x52, 0x61, 0x72, 0x21, 0x1A, 0x7]) &&
- (buf[6] === 0x0 || buf[6] === 0x1)
- ) {
- return {
- ext: 'rar',
- mime: 'application/x-rar-compressed'
- };
- }
- if (check([0x1F, 0x8B, 0x8])) {
- return {
- ext: 'gz',
- mime: 'application/gzip'
- };
- }
- if (check([0x42, 0x5A, 0x68])) {
- return {
- ext: 'bz2',
- mime: 'application/x-bzip2'
- };
- }
- if (check([0x37, 0x7A, 0xBC, 0xAF, 0x27, 0x1C])) {
- return {
- ext: '7z',
- mime: 'application/x-7z-compressed'
- };
- }
- if (check([0x78, 0x01])) {
- return {
- ext: 'dmg',
- mime: 'application/x-apple-diskimage'
- };
- }
- if (
- (
- check([0x0, 0x0, 0x0]) &&
- (buf[3] === 0x18 || buf[3] === 0x20) &&
- check([0x66, 0x74, 0x79, 0x70], {offset: 4})
- ) ||
- check([0x33, 0x67, 0x70, 0x35]) ||
- (
- check([0x0, 0x0, 0x0, 0x1C, 0x66, 0x74, 0x79, 0x70, 0x6D, 0x70, 0x34, 0x32]) &&
- check([0x6D, 0x70, 0x34, 0x31, 0x6D, 0x70, 0x34, 0x32, 0x69, 0x73, 0x6F, 0x6D], {offset: 16})
- ) ||
- check([0x0, 0x0, 0x0, 0x1C, 0x66, 0x74, 0x79, 0x70, 0x69, 0x73, 0x6F, 0x6D]) ||
- check([0x0, 0x0, 0x0, 0x1C, 0x66, 0x74, 0x79, 0x70, 0x6D, 0x70, 0x34, 0x32, 0x0, 0x0, 0x0, 0x0])
- ) {
- return {
- ext: 'mp4',
- mime: 'video/mp4'
- };
- }
- if (check([0x0, 0x0, 0x0, 0x1C, 0x66, 0x74, 0x79, 0x70, 0x4D, 0x34, 0x56])) {
- return {
- ext: 'm4v',
- mime: 'video/x-m4v'
- };
- }
- if (check([0x4D, 0x54, 0x68, 0x64])) {
- return {
- ext: 'mid',
- mime: 'audio/midi'
- };
- }
- // https://github.com/threatstack/libmagic/blob/master/magic/Magdir/matroska
- if (check([0x1A, 0x45, 0xDF, 0xA3])) {
- const sliced = buf.subarray(4, 4 + 4096);
- const idPos = sliced.findIndex((el, i, arr) => arr[i] === 0x42 && arr[i + 1] === 0x82);
- if (idPos >= 0) {
- const docTypePos = idPos + 3;
- const findDocType = type => Array.from(type).every((c, i) => sliced[docTypePos + i] === c.charCodeAt(0));
- if (findDocType('matroska')) {
- return {
- ext: 'mkv',
- mime: 'video/x-matroska'
- };
- }
- if (findDocType('webm')) {
- return {
- ext: 'webm',
- mime: 'video/webm'
- };
- }
- }
- }
- if (check([0x0, 0x0, 0x0, 0x14, 0x66, 0x74, 0x79, 0x70, 0x71, 0x74, 0x20, 0x20]) ||
- check([0x66, 0x72, 0x65, 0x65], {offset: 4}) ||
- check([0x66, 0x74, 0x79, 0x70, 0x71, 0x74, 0x20, 0x20], {offset: 4}) ||
- check([0x6D, 0x64, 0x61, 0x74], {offset: 4}) || // MJPEG
- check([0x77, 0x69, 0x64, 0x65], {offset: 4})) {
- return {
- ext: 'mov',
- mime: 'video/quicktime'
- };
- }
- if (
- check([0x52, 0x49, 0x46, 0x46]) &&
- check([0x41, 0x56, 0x49], {offset: 8})
- ) {
- return {
- ext: 'avi',
- mime: 'video/x-msvideo'
- };
- }
- if (check([0x30, 0x26, 0xB2, 0x75, 0x8E, 0x66, 0xCF, 0x11, 0xA6, 0xD9])) {
- return {
- ext: 'wmv',
- mime: 'video/x-ms-wmv'
- };
- }
- if (check([0x0, 0x0, 0x1, 0xBA])) {
- return {
- ext: 'mpg',
- mime: 'video/mpeg'
- };
- }
- if (
- check([0x49, 0x44, 0x33]) ||
- check([0xFF, 0xFB])
- ) {
- return {
- ext: 'mp3',
- mime: 'audio/mpeg'
- };
- }
- if (
- check([0x66, 0x74, 0x79, 0x70, 0x4D, 0x34, 0x41], {offset: 4}) ||
- check([0x4D, 0x34, 0x41, 0x20])
- ) {
- return {
- ext: 'm4a',
- mime: 'audio/m4a'
- };
- }
- // Needs to be before `ogg` check
- if (check([0x4F, 0x70, 0x75, 0x73, 0x48, 0x65, 0x61, 0x64], {offset: 28})) {
- return {
- ext: 'opus',
- mime: 'audio/opus'
- };
- }
- if (check([0x4F, 0x67, 0x67, 0x53])) {
- return {
- ext: 'ogg',
- mime: 'audio/ogg'
- };
- }
- if (check([0x66, 0x4C, 0x61, 0x43])) {
- return {
- ext: 'flac',
- mime: 'audio/x-flac'
- };
- }
- if (
- check([0x52, 0x49, 0x46, 0x46]) &&
- check([0x57, 0x41, 0x56, 0x45], {offset: 8})
- ) {
- return {
- ext: 'wav',
- mime: 'audio/x-wav'
- };
- }
- if (check([0x23, 0x21, 0x41, 0x4D, 0x52, 0x0A])) {
- return {
- ext: 'amr',
- mime: 'audio/amr'
- };
- }
- if (check([0x25, 0x50, 0x44, 0x46])) {
- return {
- ext: 'pdf',
- mime: 'application/pdf'
- };
- }
- if (check([0x4D, 0x5A])) {
- return {
- ext: 'exe',
- mime: 'application/x-msdownload'
- };
- }
- if (
- (buf[0] === 0x43 || buf[0] === 0x46) &&
- check([0x57, 0x53], {offset: 1})
- ) {
- return {
- ext: 'swf',
- mime: 'application/x-shockwave-flash'
- };
- }
- if (check([0x7B, 0x5C, 0x72, 0x74, 0x66])) {
- return {
- ext: 'rtf',
- mime: 'application/rtf'
- };
- }
- if (check([0x00, 0x61, 0x73, 0x6D])) {
- return {
- ext: 'wasm',
- mime: 'application/wasm'
- };
- }
- if (
- check([0x77, 0x4F, 0x46, 0x46]) &&
- (
- check([0x00, 0x01, 0x00, 0x00], {offset: 4}) ||
- check([0x4F, 0x54, 0x54, 0x4F], {offset: 4})
- )
- ) {
- return {
- ext: 'woff',
- mime: 'font/woff'
- };
- }
- if (
- check([0x77, 0x4F, 0x46, 0x32]) &&
- (
- check([0x00, 0x01, 0x00, 0x00], {offset: 4}) ||
- check([0x4F, 0x54, 0x54, 0x4F], {offset: 4})
- )
- ) {
- return {
- ext: 'woff2',
- mime: 'font/woff2'
- };
- }
- if (
- check([0x4C, 0x50], {offset: 34}) &&
- (
- check([0x00, 0x00, 0x01], {offset: 8}) ||
- check([0x01, 0x00, 0x02], {offset: 8}) ||
- check([0x02, 0x00, 0x02], {offset: 8})
- )
- ) {
- return {
- ext: 'eot',
- mime: 'application/octet-stream'
- };
- }
- if (check([0x00, 0x01, 0x00, 0x00, 0x00])) {
- return {
- ext: 'ttf',
- mime: 'font/ttf'
- };
- }
- if (check([0x4F, 0x54, 0x54, 0x4F, 0x00])) {
- return {
- ext: 'otf',
- mime: 'font/otf'
- };
- }
- if (check([0x00, 0x00, 0x01, 0x00])) {
- return {
- ext: 'ico',
- mime: 'image/x-icon'
- };
- }
- if (check([0x46, 0x4C, 0x56, 0x01])) {
- return {
- ext: 'flv',
- mime: 'video/x-flv'
- };
- }
- if (check([0x25, 0x21])) {
- return {
- ext: 'ps',
- mime: 'application/postscript'
- };
- }
- if (check([0xFD, 0x37, 0x7A, 0x58, 0x5A, 0x00])) {
- return {
- ext: 'xz',
- mime: 'application/x-xz'
- };
- }
- if (check([0x53, 0x51, 0x4C, 0x69])) {
- return {
- ext: 'sqlite',
- mime: 'application/x-sqlite3'
- };
- }
- if (check([0x4E, 0x45, 0x53, 0x1A])) {
- return {
- ext: 'nes',
- mime: 'application/x-nintendo-nes-rom'
- };
- }
- if (check([0x43, 0x72, 0x32, 0x34])) {
- return {
- ext: 'crx',
- mime: 'application/x-google-chrome-extension'
- };
- }
- if (
- check([0x4D, 0x53, 0x43, 0x46]) ||
- check([0x49, 0x53, 0x63, 0x28])
- ) {
- return {
- ext: 'cab',
- mime: 'application/vnd.ms-cab-compressed'
- };
- }
- // Needs to be before `ar` check
- if (check([0x21, 0x3C, 0x61, 0x72, 0x63, 0x68, 0x3E, 0x0A, 0x64, 0x65, 0x62, 0x69, 0x61, 0x6E, 0x2D, 0x62, 0x69, 0x6E, 0x61, 0x72, 0x79])) {
- return {
- ext: 'deb',
- mime: 'application/x-deb'
- };
- }
- if (check([0x21, 0x3C, 0x61, 0x72, 0x63, 0x68, 0x3E])) {
- return {
- ext: 'ar',
- mime: 'application/x-unix-archive'
- };
- }
- if (check([0xED, 0xAB, 0xEE, 0xDB])) {
- return {
- ext: 'rpm',
- mime: 'application/x-rpm'
- };
- }
- if (
- check([0x1F, 0xA0]) ||
- check([0x1F, 0x9D])
- ) {
- return {
- ext: 'Z',
- mime: 'application/x-compress'
- };
- }
- if (check([0x4C, 0x5A, 0x49, 0x50])) {
- return {
- ext: 'lz',
- mime: 'application/x-lzip'
- };
- }
- if (check([0xD0, 0xCF, 0x11, 0xE0, 0xA1, 0xB1, 0x1A, 0xE1])) {
- return {
- ext: 'msi',
- mime: 'application/x-msi'
- };
- }
- if (check([0x06, 0x0E, 0x2B, 0x34, 0x02, 0x05, 0x01, 0x01, 0x0D, 0x01, 0x02, 0x01, 0x01, 0x02])) {
- return {
- ext: 'mxf',
- mime: 'application/mxf'
- };
- }
- if (check([0x47], {offset: 4}) && (check([0x47], {offset: 192}) || check([0x47], {offset: 196}))) {
- return {
- ext: 'mts',
- mime: 'video/mp2t'
- };
- }
- if (check([0x42, 0x4C, 0x45, 0x4E, 0x44, 0x45, 0x52])) {
- return {
- ext: 'blend',
- mime: 'application/x-blender'
- };
- }
- if (check([0x42, 0x50, 0x47, 0xFB])) {
- return {
- ext: 'bpg',
- mime: 'image/bpg'
- };
- }
- return null;
- };
|