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Diffstat (limited to 'middleware/node_modules/iconv-lite/encodings/utf7.js')
-rw-r--r-- | middleware/node_modules/iconv-lite/encodings/utf7.js | 290 |
1 files changed, 290 insertions, 0 deletions
diff --git a/middleware/node_modules/iconv-lite/encodings/utf7.js b/middleware/node_modules/iconv-lite/encodings/utf7.js new file mode 100644 index 0000000..b7631c2 --- /dev/null +++ b/middleware/node_modules/iconv-lite/encodings/utf7.js @@ -0,0 +1,290 @@ +"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; +} + + |