PNG  IHDR;IDATxܻn0K )(pA 7LeG{ §㻢|ذaÆ 6lذaÆ 6lذaÆ 6lom$^yذag5bÆ 6lذaÆ 6lذa{ 6lذaÆ `}HFkm,mӪôô! x|'ܢ˟;E:9&ᶒ}{v]n&6 h_tڠ͵-ҫZ;Z$.Pkž)!o>}leQfJTu іچ\X=8Rن4`Vwl>nG^is"ms$ui?wbs[m6K4O.4%/bC%t Mז -lG6mrz2s%9s@-k9=)kB5\+͂Zsٲ Rn~GRC wIcIn7jJhۛNCS|j08yiHKֶۛkɈ+;SzL/F*\Ԕ#"5m2[S=gnaPeғL lذaÆ 6l^ḵaÆ 6lذaÆ 6lذa; _ذaÆ 6lذaÆ 6lذaÆ RIENDB` var Buffer = require('safe-buffer').Buffer // prototype class for hash functions function Hash (blockSize, finalSize) { this._block = Buffer.alloc(blockSize) this._finalSize = finalSize this._blockSize = blockSize this._len = 0 } Hash.prototype.update = function (data, enc) { if (typeof data === 'string') { enc = enc || 'utf8' data = Buffer.from(data, enc) } var block = this._block var blockSize = this._blockSize var length = data.length var accum = this._len for (var offset = 0; offset < length;) { var assigned = accum % blockSize var remainder = Math.min(length - offset, blockSize - assigned) for (var i = 0; i < remainder; i++) { block[assigned + i] = data[offset + i] } accum += remainder offset += remainder if ((accum % blockSize) === 0) { this._update(block) } } this._len += length return this } Hash.prototype.digest = function (enc) { var rem = this._len % this._blockSize this._block[rem] = 0x80 // zero (rem + 1) trailing bits, where (rem + 1) is the smallest // non-negative solution to the equation (length + 1 + (rem + 1)) === finalSize mod blockSize this._block.fill(0, rem + 1) if (rem >= this._finalSize) { this._update(this._block) this._block.fill(0) } var bits = this._len * 8 // uint32 if (bits <= 0xffffffff) { this._block.writeUInt32BE(bits, this._blockSize - 4) // uint64 } else { var lowBits = (bits & 0xffffffff) >>> 0 var highBits = (bits - lowBits) / 0x100000000 this._block.writeUInt32BE(highBits, this._blockSize - 8) this._block.writeUInt32BE(lowBits, this._blockSize - 4) } this._update(this._block) var hash = this._hash() return enc ? hash.toString(enc) : hash } Hash.prototype._update = function () { throw new Error('_update must be implemented by subclass') } module.exports = Hash