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author | Florian Dold <florian.dold@gmail.com> | 2017-05-03 15:35:00 +0200 |
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committer | Florian Dold <florian.dold@gmail.com> | 2017-05-03 15:35:00 +0200 |
commit | de98e0b232509d5f40c135d540a70e415272ff85 (patch) | |
tree | a79222a5b58484ab3b80d18efcaaa7ccc4769b33 /node_modules/des.js/lib/des/cipher.js | |
parent | e0c9d480a73fa629c1e4a47d3e721f1d2d345406 (diff) | |
download | wallet-core-de98e0b232509d5f40c135d540a70e415272ff85.tar.xz |
node_modules
Diffstat (limited to 'node_modules/des.js/lib/des/cipher.js')
-rw-r--r-- | node_modules/des.js/lib/des/cipher.js | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/node_modules/des.js/lib/des/cipher.js b/node_modules/des.js/lib/des/cipher.js new file mode 100644 index 000000000..d0090b4cd --- /dev/null +++ b/node_modules/des.js/lib/des/cipher.js @@ -0,0 +1,141 @@ +'use strict'; + +var assert = require('minimalistic-assert'); + +function Cipher(options) { + this.options = options; + + this.type = this.options.type; + this.blockSize = 8; + this._init(); + + this.buffer = new Array(this.blockSize); + this.bufferOff = 0; +} +module.exports = Cipher; + +Cipher.prototype._init = function _init() { + // Might be overrided +}; + +Cipher.prototype.update = function update(data) { + if (data.length === 0) + return []; + + if (this.type === 'decrypt') + return this._updateDecrypt(data); + else + return this._updateEncrypt(data); +}; + +Cipher.prototype._buffer = function _buffer(data, off) { + // Append data to buffer + var min = Math.min(this.buffer.length - this.bufferOff, data.length - off); + for (var i = 0; i < min; i++) + this.buffer[this.bufferOff + i] = data[off + i]; + this.bufferOff += min; + + // Shift next + return min; +}; + +Cipher.prototype._flushBuffer = function _flushBuffer(out, off) { + this._update(this.buffer, 0, out, off); + this.bufferOff = 0; + return this.blockSize; +}; + +Cipher.prototype._updateEncrypt = function _updateEncrypt(data) { + var inputOff = 0; + var outputOff = 0; + + var count = ((this.bufferOff + data.length) / this.blockSize) | 0; + var out = new Array(count * this.blockSize); + + if (this.bufferOff !== 0) { + inputOff += this._buffer(data, inputOff); + + if (this.bufferOff === this.buffer.length) + outputOff += this._flushBuffer(out, outputOff); + } + + // Write blocks + var max = data.length - ((data.length - inputOff) % this.blockSize); + for (; inputOff < max; inputOff += this.blockSize) { + this._update(data, inputOff, out, outputOff); + outputOff += this.blockSize; + } + + // Queue rest + for (; inputOff < data.length; inputOff++, this.bufferOff++) + this.buffer[this.bufferOff] = data[inputOff]; + + return out; +}; + +Cipher.prototype._updateDecrypt = function _updateDecrypt(data) { + var inputOff = 0; + var outputOff = 0; + + var count = Math.ceil((this.bufferOff + data.length) / this.blockSize) - 1; + var out = new Array(count * this.blockSize); + + // TODO(indutny): optimize it, this is far from optimal + for (; count > 0; count--) { + inputOff += this._buffer(data, inputOff); + outputOff += this._flushBuffer(out, outputOff); + } + + // Buffer rest of the input + inputOff += this._buffer(data, inputOff); + + return out; +}; + +Cipher.prototype.final = function final(buffer) { + var first; + if (buffer) + first = this.update(buffer); + + var last; + if (this.type === 'encrypt') + last = this._finalEncrypt(); + else + last = this._finalDecrypt(); + + if (first) + return first.concat(last); + else + return last; +}; + +Cipher.prototype._pad = function _pad(buffer, off) { + if (off === 0) + return false; + + while (off < buffer.length) + buffer[off++] = 0; + + return true; +}; + +Cipher.prototype._finalEncrypt = function _finalEncrypt() { + if (!this._pad(this.buffer, this.bufferOff)) + return []; + + var out = new Array(this.blockSize); + this._update(this.buffer, 0, out, 0); + return out; +}; + +Cipher.prototype._unpad = function _unpad(buffer) { + return buffer; +}; + +Cipher.prototype._finalDecrypt = function _finalDecrypt() { + assert.equal(this.bufferOff, this.blockSize, 'Not enough data to decrypt'); + var out = new Array(this.blockSize); + this._flushBuffer(out, 0); + + return this._unpad(out); +}; |