lapo.it
1/*global Hex, Base64, ASN1 */
2"use strict";
3
4var maxLength = 10240,
5 reHex = /^\s*(?:[0-9A-Fa-f][0-9A-Fa-f]\s*)+$/,
6 tree = id('tree'),
7 dump = id('dump'),
8 wantHex = id('wantHex'),
9 area = id('area'),
10 file = id('file'),
11 hash = null;
12function id(elem) {
13 return document.getElementById(elem);
14}
15function text(el, string) {
16 if ('textContent' in el)
17 el.textContent = string;
18 else
19 el.innerText = string;
20}
21function decode(der) {
22 tree.innerHTML = '';
23 dump.innerHTML = '';
24 try {
25 var asn1 = ASN1.decode(der);
26 tree.appendChild(asn1.toDOM());
27 if (wantHex.checked)
28 dump.appendChild(asn1.toHexDOM());
29 var hex = (der.length < maxLength) ? asn1.toHexString() : '';
30 if (area.value === '')
31 area.value = hex;
32 try {
33 window.location.hash = hash = '#' + hex;
34 } catch (e) { // fails with "Access Denied" on IE with URLs longer than ~2048 chars
35 window.location.hash = hash = '#';
36 }
37 } catch (e) {
38 text(tree, e);
39 }
40}
41function decodeArea() {
42 try {
43 var val = area.value,
44 der = reHex.test(val) ? Hex.decode(val) : Base64.unarmor(val);
45 decode(der);
46 } catch (e) {
47 text(tree, e);
48 dump.innerHTML = '';
49 }
50}
51function decodeBinaryString(str) {
52 var der;
53 try {
54 if (reHex.test(str))
55 der = Hex.decode(str);
56 else if (Base64.re.test(str))
57 der = Base64.unarmor(str);
58 else
59 der = str;
60 decode(der);
61 } catch (e) {
62 text(tree, 'Cannot decode file.');
63 dump.innerHTML = '';
64 }
65}
66function clearAll() {
67 area.value = '';
68 tree.innerHTML = '';
69 dump.innerHTML = '';
70 hash = window.location.hash = '';
71}
72// this is only used if window.FileReader
73function read(f) {
74 area.value = ''; // clear text area, will get hex content
75 var r = new FileReader();
76 r.onloadend = function () {
77 if (r.error)
78 alert("Your browser couldn't read the specified file (error code " + r.error.code + ").");
79 else
80 decodeBinaryString(r.result);
81 };
82 r.readAsBinaryString(f);
83}
84function load() {
85 if (file.files.length === 0)
86 alert("Select a file to load first.");
87 else
88 read(file.files[0]);
89}
90function loadFromHash() {
91 if (window.location.hash && window.location.hash != hash) {
92 hash = window.location.hash;
93 // Firefox is not consistent with other browsers and return an
94 // already-decoded hash string so we risk double-decoding here,
95 // but since % is not allowed in base64 nor hexadecimal, it's ok
96 area.value = decodeURIComponent(hash.substr(1));
97 decodeArea();
98 }
99}
100function stop(e) {
101 e.stopPropagation();
102 e.preventDefault();
103}
104function dragAccept(e) {
105 stop(e);
106 if (e.dataTransfer.files.length > 0)
107 read(e.dataTransfer.files[0]);
108}
109// main
110if ('onhashchange' in window)
111 window.onhashchange = loadFromHash;
112loadFromHash();
113document.ondragover = stop;
114document.ondragleave = stop;
115if ('FileReader' in window) {
116 file.style.display = 'block';
117 file.onchange = load;
118 document.ondrop = dragAccept;
119}