| "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; |
| } |
| |
| |