forked from lix-project/lix-website
291 lines
9 KiB
JavaScript
291 lines
9 KiB
JavaScript
|
"use strict";
|
||
|
var Buffer = require("safer-buffer").Buffer;
|
||
|
|
||
|
// UTF-7 codec, according to https://tools.ietf.org/html/rfc2152
|
||
|
// See also below a UTF-7-IMAP codec, according to http://tools.ietf.org/html/rfc3501#section-5.1.3
|
||
|
|
||
|
exports.utf7 = Utf7Codec;
|
||
|
exports.unicode11utf7 = 'utf7'; // Alias UNICODE-1-1-UTF-7
|
||
|
function Utf7Codec(codecOptions, iconv) {
|
||
|
this.iconv = iconv;
|
||
|
};
|
||
|
|
||
|
Utf7Codec.prototype.encoder = Utf7Encoder;
|
||
|
Utf7Codec.prototype.decoder = Utf7Decoder;
|
||
|
Utf7Codec.prototype.bomAware = true;
|
||
|
|
||
|
|
||
|
// -- Encoding
|
||
|
|
||
|
var nonDirectChars = /[^A-Za-z0-9'\(\),-\.\/:\? \n\r\t]+/g;
|
||
|
|
||
|
function Utf7Encoder(options, codec) {
|
||
|
this.iconv = codec.iconv;
|
||
|
}
|
||
|
|
||
|
Utf7Encoder.prototype.write = function(str) {
|
||
|
// Naive implementation.
|
||
|
// Non-direct chars are encoded as "+<base64>-"; single "+" char is encoded as "+-".
|
||
|
return Buffer.from(str.replace(nonDirectChars, function(chunk) {
|
||
|
return "+" + (chunk === '+' ? '' :
|
||
|
this.iconv.encode(chunk, 'utf16-be').toString('base64').replace(/=+$/, ''))
|
||
|
+ "-";
|
||
|
}.bind(this)));
|
||
|
}
|
||
|
|
||
|
Utf7Encoder.prototype.end = function() {
|
||
|
}
|
||
|
|
||
|
|
||
|
// -- Decoding
|
||
|
|
||
|
function Utf7Decoder(options, codec) {
|
||
|
this.iconv = codec.iconv;
|
||
|
this.inBase64 = false;
|
||
|
this.base64Accum = '';
|
||
|
}
|
||
|
|
||
|
var base64Regex = /[A-Za-z0-9\/+]/;
|
||
|
var base64Chars = [];
|
||
|
for (var i = 0; i < 256; i++)
|
||
|
base64Chars[i] = base64Regex.test(String.fromCharCode(i));
|
||
|
|
||
|
var plusChar = '+'.charCodeAt(0),
|
||
|
minusChar = '-'.charCodeAt(0),
|
||
|
andChar = '&'.charCodeAt(0);
|
||
|
|
||
|
Utf7Decoder.prototype.write = function(buf) {
|
||
|
var res = "", lastI = 0,
|
||
|
inBase64 = this.inBase64,
|
||
|
base64Accum = this.base64Accum;
|
||
|
|
||
|
// The decoder is more involved as we must handle chunks in stream.
|
||
|
|
||
|
for (var i = 0; i < buf.length; i++) {
|
||
|
if (!inBase64) { // We're in direct mode.
|
||
|
// Write direct chars until '+'
|
||
|
if (buf[i] == plusChar) {
|
||
|
res += this.iconv.decode(buf.slice(lastI, i), "ascii"); // Write direct chars.
|
||
|
lastI = i+1;
|
||
|
inBase64 = true;
|
||
|
}
|
||
|
} else { // We decode base64.
|
||
|
if (!base64Chars[buf[i]]) { // Base64 ended.
|
||
|
if (i == lastI && buf[i] == minusChar) {// "+-" -> "+"
|
||
|
res += "+";
|
||
|
} else {
|
||
|
var b64str = base64Accum + buf.slice(lastI, i).toString();
|
||
|
res += this.iconv.decode(Buffer.from(b64str, 'base64'), "utf16-be");
|
||
|
}
|
||
|
|
||
|
if (buf[i] != minusChar) // Minus is absorbed after base64.
|
||
|
i--;
|
||
|
|
||
|
lastI = i+1;
|
||
|
inBase64 = false;
|
||
|
base64Accum = '';
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (!inBase64) {
|
||
|
res += this.iconv.decode(buf.slice(lastI), "ascii"); // Write direct chars.
|
||
|
} else {
|
||
|
var b64str = base64Accum + buf.slice(lastI).toString();
|
||
|
|
||
|
var canBeDecoded = b64str.length - (b64str.length % 8); // Minimal chunk: 2 quads -> 2x3 bytes -> 3 chars.
|
||
|
base64Accum = b64str.slice(canBeDecoded); // The rest will be decoded in future.
|
||
|
b64str = b64str.slice(0, canBeDecoded);
|
||
|
|
||
|
res += this.iconv.decode(Buffer.from(b64str, 'base64'), "utf16-be");
|
||
|
}
|
||
|
|
||
|
this.inBase64 = inBase64;
|
||
|
this.base64Accum = base64Accum;
|
||
|
|
||
|
return res;
|
||
|
}
|
||
|
|
||
|
Utf7Decoder.prototype.end = function() {
|
||
|
var res = "";
|
||
|
if (this.inBase64 && this.base64Accum.length > 0)
|
||
|
res = this.iconv.decode(Buffer.from(this.base64Accum, 'base64'), "utf16-be");
|
||
|
|
||
|
this.inBase64 = false;
|
||
|
this.base64Accum = '';
|
||
|
return res;
|
||
|
}
|
||
|
|
||
|
|
||
|
// UTF-7-IMAP codec.
|
||
|
// RFC3501 Sec. 5.1.3 Modified UTF-7 (http://tools.ietf.org/html/rfc3501#section-5.1.3)
|
||
|
// Differences:
|
||
|
// * Base64 part is started by "&" instead of "+"
|
||
|
// * Direct characters are 0x20-0x7E, except "&" (0x26)
|
||
|
// * In Base64, "," is used instead of "/"
|
||
|
// * Base64 must not be used to represent direct characters.
|
||
|
// * No implicit shift back from Base64 (should always end with '-')
|
||
|
// * String must end in non-shifted position.
|
||
|
// * "-&" while in base64 is not allowed.
|
||
|
|
||
|
|
||
|
exports.utf7imap = Utf7IMAPCodec;
|
||
|
function Utf7IMAPCodec(codecOptions, iconv) {
|
||
|
this.iconv = iconv;
|
||
|
};
|
||
|
|
||
|
Utf7IMAPCodec.prototype.encoder = Utf7IMAPEncoder;
|
||
|
Utf7IMAPCodec.prototype.decoder = Utf7IMAPDecoder;
|
||
|
Utf7IMAPCodec.prototype.bomAware = true;
|
||
|
|
||
|
|
||
|
// -- Encoding
|
||
|
|
||
|
function Utf7IMAPEncoder(options, codec) {
|
||
|
this.iconv = codec.iconv;
|
||
|
this.inBase64 = false;
|
||
|
this.base64Accum = Buffer.alloc(6);
|
||
|
this.base64AccumIdx = 0;
|
||
|
}
|
||
|
|
||
|
Utf7IMAPEncoder.prototype.write = function(str) {
|
||
|
var inBase64 = this.inBase64,
|
||
|
base64Accum = this.base64Accum,
|
||
|
base64AccumIdx = this.base64AccumIdx,
|
||
|
buf = Buffer.alloc(str.length*5 + 10), bufIdx = 0;
|
||
|
|
||
|
for (var i = 0; i < str.length; i++) {
|
||
|
var uChar = str.charCodeAt(i);
|
||
|
if (0x20 <= uChar && uChar <= 0x7E) { // Direct character or '&'.
|
||
|
if (inBase64) {
|
||
|
if (base64AccumIdx > 0) {
|
||
|
bufIdx += buf.write(base64Accum.slice(0, base64AccumIdx).toString('base64').replace(/\//g, ',').replace(/=+$/, ''), bufIdx);
|
||
|
base64AccumIdx = 0;
|
||
|
}
|
||
|
|
||
|
buf[bufIdx++] = minusChar; // Write '-', then go to direct mode.
|
||
|
inBase64 = false;
|
||
|
}
|
||
|
|
||
|
if (!inBase64) {
|
||
|
buf[bufIdx++] = uChar; // Write direct character
|
||
|
|
||
|
if (uChar === andChar) // Ampersand -> '&-'
|
||
|
buf[bufIdx++] = minusChar;
|
||
|
}
|
||
|
|
||
|
} else { // Non-direct character
|
||
|
if (!inBase64) {
|
||
|
buf[bufIdx++] = andChar; // Write '&', then go to base64 mode.
|
||
|
inBase64 = true;
|
||
|
}
|
||
|
if (inBase64) {
|
||
|
base64Accum[base64AccumIdx++] = uChar >> 8;
|
||
|
base64Accum[base64AccumIdx++] = uChar & 0xFF;
|
||
|
|
||
|
if (base64AccumIdx == base64Accum.length) {
|
||
|
bufIdx += buf.write(base64Accum.toString('base64').replace(/\//g, ','), bufIdx);
|
||
|
base64AccumIdx = 0;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
this.inBase64 = inBase64;
|
||
|
this.base64AccumIdx = base64AccumIdx;
|
||
|
|
||
|
return buf.slice(0, bufIdx);
|
||
|
}
|
||
|
|
||
|
Utf7IMAPEncoder.prototype.end = function() {
|
||
|
var buf = Buffer.alloc(10), bufIdx = 0;
|
||
|
if (this.inBase64) {
|
||
|
if (this.base64AccumIdx > 0) {
|
||
|
bufIdx += buf.write(this.base64Accum.slice(0, this.base64AccumIdx).toString('base64').replace(/\//g, ',').replace(/=+$/, ''), bufIdx);
|
||
|
this.base64AccumIdx = 0;
|
||
|
}
|
||
|
|
||
|
buf[bufIdx++] = minusChar; // Write '-', then go to direct mode.
|
||
|
this.inBase64 = false;
|
||
|
}
|
||
|
|
||
|
return buf.slice(0, bufIdx);
|
||
|
}
|
||
|
|
||
|
|
||
|
// -- Decoding
|
||
|
|
||
|
function Utf7IMAPDecoder(options, codec) {
|
||
|
this.iconv = codec.iconv;
|
||
|
this.inBase64 = false;
|
||
|
this.base64Accum = '';
|
||
|
}
|
||
|
|
||
|
var base64IMAPChars = base64Chars.slice();
|
||
|
base64IMAPChars[','.charCodeAt(0)] = true;
|
||
|
|
||
|
Utf7IMAPDecoder.prototype.write = function(buf) {
|
||
|
var res = "", lastI = 0,
|
||
|
inBase64 = this.inBase64,
|
||
|
base64Accum = this.base64Accum;
|
||
|
|
||
|
// The decoder is more involved as we must handle chunks in stream.
|
||
|
// It is forgiving, closer to standard UTF-7 (for example, '-' is optional at the end).
|
||
|
|
||
|
for (var i = 0; i < buf.length; i++) {
|
||
|
if (!inBase64) { // We're in direct mode.
|
||
|
// Write direct chars until '&'
|
||
|
if (buf[i] == andChar) {
|
||
|
res += this.iconv.decode(buf.slice(lastI, i), "ascii"); // Write direct chars.
|
||
|
lastI = i+1;
|
||
|
inBase64 = true;
|
||
|
}
|
||
|
} else { // We decode base64.
|
||
|
if (!base64IMAPChars[buf[i]]) { // Base64 ended.
|
||
|
if (i == lastI && buf[i] == minusChar) { // "&-" -> "&"
|
||
|
res += "&";
|
||
|
} else {
|
||
|
var b64str = base64Accum + buf.slice(lastI, i).toString().replace(/,/g, '/');
|
||
|
res += this.iconv.decode(Buffer.from(b64str, 'base64'), "utf16-be");
|
||
|
}
|
||
|
|
||
|
if (buf[i] != minusChar) // Minus may be absorbed after base64.
|
||
|
i--;
|
||
|
|
||
|
lastI = i+1;
|
||
|
inBase64 = false;
|
||
|
base64Accum = '';
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (!inBase64) {
|
||
|
res += this.iconv.decode(buf.slice(lastI), "ascii"); // Write direct chars.
|
||
|
} else {
|
||
|
var b64str = base64Accum + buf.slice(lastI).toString().replace(/,/g, '/');
|
||
|
|
||
|
var canBeDecoded = b64str.length - (b64str.length % 8); // Minimal chunk: 2 quads -> 2x3 bytes -> 3 chars.
|
||
|
base64Accum = b64str.slice(canBeDecoded); // The rest will be decoded in future.
|
||
|
b64str = b64str.slice(0, canBeDecoded);
|
||
|
|
||
|
res += this.iconv.decode(Buffer.from(b64str, 'base64'), "utf16-be");
|
||
|
}
|
||
|
|
||
|
this.inBase64 = inBase64;
|
||
|
this.base64Accum = base64Accum;
|
||
|
|
||
|
return res;
|
||
|
}
|
||
|
|
||
|
Utf7IMAPDecoder.prototype.end = function() {
|
||
|
var res = "";
|
||
|
if (this.inBase64 && this.base64Accum.length > 0)
|
||
|
res = this.iconv.decode(Buffer.from(this.base64Accum, 'base64'), "utf16-be");
|
||
|
|
||
|
this.inBase64 = false;
|
||
|
this.base64Accum = '';
|
||
|
return res;
|
||
|
}
|
||
|
|
||
|
|