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author | 2020-11-16 00:10:28 +0100 | |
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committer | 2020-11-16 00:10:28 +0100 | |
commit | e06ec920f7a5d784e674c4c4b4e6d1da3dc7391d (patch) | |
tree | 55713f725f77b44ebfec86e4eec3ce33e71458ca /node_modules/browserify-aes/authCipher.js | |
download | website_creator-e06ec920f7a5d784e674c4c4b4e6d1da3dc7391d.tar.gz website_creator-e06ec920f7a5d784e674c4c4b4e6d1da3dc7391d.tar.bz2 website_creator-e06ec920f7a5d784e674c4c4b4e6d1da3dc7391d.zip |
api, login, auth
Diffstat (limited to 'node_modules/browserify-aes/authCipher.js')
-rw-r--r-- | node_modules/browserify-aes/authCipher.js | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/node_modules/browserify-aes/authCipher.js b/node_modules/browserify-aes/authCipher.js new file mode 100644 index 0000000..c6e8a76 --- /dev/null +++ b/node_modules/browserify-aes/authCipher.js @@ -0,0 +1,117 @@ +var aes = require('./aes') +var Buffer = require('safe-buffer').Buffer +var Transform = require('cipher-base') +var inherits = require('inherits') +var GHASH = require('./ghash') +var xor = require('buffer-xor') +var incr32 = require('./incr32') + +function xorTest (a, b) { + var out = 0 + if (a.length !== b.length) out++ + + var len = Math.min(a.length, b.length) + for (var i = 0; i < len; ++i) { + out += (a[i] ^ b[i]) + } + + return out +} + +function calcIv (self, iv, ck) { + if (iv.length === 12) { + self._finID = Buffer.concat([iv, Buffer.from([0, 0, 0, 1])]) + return Buffer.concat([iv, Buffer.from([0, 0, 0, 2])]) + } + var ghash = new GHASH(ck) + var len = iv.length + var toPad = len % 16 + ghash.update(iv) + if (toPad) { + toPad = 16 - toPad + ghash.update(Buffer.alloc(toPad, 0)) + } + ghash.update(Buffer.alloc(8, 0)) + var ivBits = len * 8 + var tail = Buffer.alloc(8) + tail.writeUIntBE(ivBits, 0, 8) + ghash.update(tail) + self._finID = ghash.state + var out = Buffer.from(self._finID) + incr32(out) + return out +} +function StreamCipher (mode, key, iv, decrypt) { + Transform.call(this) + + var h = Buffer.alloc(4, 0) + + this._cipher = new aes.AES(key) + var ck = this._cipher.encryptBlock(h) + this._ghash = new GHASH(ck) + iv = calcIv(this, iv, ck) + + this._prev = Buffer.from(iv) + this._cache = Buffer.allocUnsafe(0) + this._secCache = Buffer.allocUnsafe(0) + this._decrypt = decrypt + this._alen = 0 + this._len = 0 + this._mode = mode + + this._authTag = null + this._called = false +} + +inherits(StreamCipher, Transform) + +StreamCipher.prototype._update = function (chunk) { + if (!this._called && this._alen) { + var rump = 16 - (this._alen % 16) + if (rump < 16) { + rump = Buffer.alloc(rump, 0) + this._ghash.update(rump) + } + } + + this._called = true + var out = this._mode.encrypt(this, chunk) + if (this._decrypt) { + this._ghash.update(chunk) + } else { + this._ghash.update(out) + } + this._len += chunk.length + return out +} + +StreamCipher.prototype._final = function () { + if (this._decrypt && !this._authTag) throw new Error('Unsupported state or unable to authenticate data') + + var tag = xor(this._ghash.final(this._alen * 8, this._len * 8), this._cipher.encryptBlock(this._finID)) + if (this._decrypt && xorTest(tag, this._authTag)) throw new Error('Unsupported state or unable to authenticate data') + + this._authTag = tag + this._cipher.scrub() +} + +StreamCipher.prototype.getAuthTag = function getAuthTag () { + if (this._decrypt || !Buffer.isBuffer(this._authTag)) throw new Error('Attempting to get auth tag in unsupported state') + + return this._authTag +} + +StreamCipher.prototype.setAuthTag = function setAuthTag (tag) { + if (!this._decrypt) throw new Error('Attempting to set auth tag in unsupported state') + + this._authTag = tag +} + +StreamCipher.prototype.setAAD = function setAAD (buf) { + if (this._called) throw new Error('Attempting to set AAD in unsupported state') + + this._ghash.update(buf) + this._alen += buf.length +} + +module.exports = StreamCipher |