blockchain-link

crypto = require("crypto") BigInteger = require("jsbn") alphabet = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz" nbi = -> new BigInteger(null) nbv = (i) -> r = nbi() r.fromInt i r BigInteger.valueOf = nbv base = BigInteger.valueOf(58) BigInteger.fromByteArrayUnsigned = (ba) -> unless ba.length ba.valueOf 0 else if ba[0] & 0x80 new BigInteger([0].concat(ba)) else new BigInteger(ba) BigInteger::toByteArrayUnsigned = -> ba = @abs().toByteArray() if ba.length ba = ba.slice(1) if ba[0] is 0 ba.map (v) -> (if (v < 0) then v + 256 else v) else ba hexToBytes = (hex) -> bytes = [] c = 0 while c < hex.length bytes.push parseInt(hex.substr(c, 2), 16) c += 2 bytes bytesToHex = (bytes) -> hex = [] i = 0 while i < bytes.length hex.push (bytes[i] >>> 4).toString(16) hex.push (bytes[i] & 0xF).toString(16) i++ hex.join "" encodeBase58 = (input) -> bi = BigInteger.fromByteArrayUnsigned(input) chars = [] while bi.compareTo(base) >= 0 mod = bi.mod(base) chars.unshift alphabet[mod.intValue()] bi = bi.subtract(mod).divide(base) chars.unshift alphabet[bi.intValue()] i = 0 while i < input.length if input[i] is 0x00 chars.unshift alphabet[0] else break i++ chars.join "" decodeBase58 = (input) -> bi = BigInteger.valueOf(0) leadingZerosNum = 0 i = input.length - 1 while i >= 0 alphaIndex = alphabet.indexOf(input[i]) throw "Invalid character" if alphaIndex < 0 bi = bi.add(BigInteger.valueOf(alphaIndex).multiply(base.pow(input.length - 1 - i))) # This counts leading zero bytes if input[i] is "1" leadingZerosNum++ else leadingZerosNum = 0 i-- bytes = bi.toByteArrayUnsigned() # Add leading zeros bytes.unshift 0 while leadingZerosNum-- > 0 bytes decimalToHex = (d, padding) -> hex = Number(d).toString(16) padding = (if typeof (padding) is "undefined" or padding is null then 2 else padding) hex = "0" + hex while hex.length < padding hex hashBuffer = (algo, buffer) -> hash = crypto.createHash algo hash.update buffer hash.digest() encodeAddress = (buf, version) -> version = version or 0x00 padding = new Buffer(21) # version byte + 20 bytes = 21 padding.fill version # fill with version buf.copy padding, 1, 0 # start a 1 to leave version byte at start twice = hashBuffer "sha256", hashBuffer "sha256", padding fin = new Buffer(25) # version byte + 20 bytes + 4 byte checksum = 25 padding.copy fin twice.copy fin, 21 # checksum starts at 21 which is version byte + 20 bytes encodeBase58 hexToBytes(fin.toString("hex")) encodeAddresses = (buf, version) -> version = version or 0x00 result = [] x = 0 while x < buf.length next = buf.slice(x, x + 20) # get the next 20 bytes result.push encodeAddress(next, version) x = x + 20 result opCodes = startSequenceOpCode: "4c696e6b" inlinePayloadOpCode: "01" attachmentPayloadOpCode: "02" mimeTypeOpCode: "03" payloadEncodingOpCode: "04" payloadMD5OpCode: "05" payloadSHA1OpCode: "06" payloadSHA256OpCode: "07" nameOpCode: "10" descriptionOpCode: "11" keywordsOpCode: "12" uriOpCode: "13" filenameOpCode: "14" originalCreationDateOpCode: "15" lastModifiedDateOpCode: "16" licenseOpCode: "17" referencesTransactionOpCode: "F1" replacesTransactionOpCode: "F2" nextTransactionOpCode: "FF" endSequence: "00" class LinkSequenceBuilder constructor: (@version) -> str: opCodes.startSequenceOpCode toString: -> @str + opCodes.endSequence addName: (name) -> @str += @encodeName(name) addDescription: (description) -> @str += @encodeDescription description addURI: (uri) -> @str += @encodeURI uri addFilename: (filename) -> @str += @encodeFilename filename addMimeType: (mimeType) -> @str += @encodeMimeType mimeType addKeywords: (keywords) -> @str += @encodeKeywords keywords addOriginalCreationDate: (date) -> @str += @encodeOriginalCreationDate date addLastModifiedDate: (date) -> @str += @encodeLastModifiedDate date addPayloadInline: (payload) -> @str += @encodePayloadInline payload addPayloadAttachment: (buf) -> @str += @encodePayloadAttachment buf addPayloadMD5: (buf) -> @str += @encodePayloadMD5Buffer buf addPayloadSHA1: (buf) -> @str += @encodePayloadSHA1Buffer buf addPayloadSHA256: (buf) -> @str += @encodePayloadSHA256Buffer buf addLicense:(license)-> @str += @encodeLicense license getAddresses: () -> encodeAddresses new Buffer(@toString(), "hex"), @version encodeBuffer: (buf) -> decimalToHex(buf.length, 4) + buf.toString("hex"); encodeString: (str) -> @encodeBuffer(new Buffer(str)) encodePayloadInline: (str) -> opCodes.inlinePayloadOpCode + @encodeString(str) encodePayloadAttachment: (buf) -> opCodes.attachmentPayloadOpCode + @encodeBuffer(buf) encodePayloadEncoding: (str) -> opCodes.payloadEncodingOpCode + @encodeString(str) encodePayloadMD5Buffer: (buf) -> opCodes.payloadMD5OpCode + hashBuffer("md5", buf).toString "hex" encodePayloadSHA1Buffer: (buf) -> opCodes.payloadSHA1OpCode + hashBuffer("sha1", buf).toString "hex" encodePayloadSHA256Buffer: (buf) -> opCodes.payloadSHA256OpCode + hashBuffer("sha256", buf).toString "hex" encodeName: (str) -> opCodes.nameOpCode + @encodeString(str) encodeDescription: (str) -> opCodes.descriptionOpCode + @encodeString(str) encodeURI: (str) -> opCodes.uriOpCode + @encodeString(str) encodeFilename: (str) -> opCodes.filenameOpCode + @encodeString(str) encodeKeywords: (str) -> opCodes.keywordsOpCode + @encodeString(str) encodeMimeType: (str) -> opCodes.mimeTypeOpCode + @encodeString(str) encodeOriginalCreationDate: (date) -> opCodes.originalCreationDateOpCode + decimalToHex(date.getTime(), 12) encodeLastModifiedDate: (date) -> opCodes.lastModifiedDateOpCode + decimalToHex(date.getTime(), 12) encodeLicense: (license) -> opcodes.licenseOpCode + @encodeString(str) class LinkSequenceDecoder decode: (addresses) -> sequence = new Buffer(addresses.length * 20) sequence.fill 0x00 for x of addresses new Buffer(bytesToHex(decodeBase58(addresses[x]).slice(1)), "hex").copy sequence, x * 20 startSequence= new Buffer(4) sequence.copy startSequence firstFour = startSequence.toString("utf-8") throw "First 4 bytes were: " + firstFour unless firstFour is "Link" ip = 4 running = true result = {} while running nextOp = new Buffer(1) sequence.copy nextOp, 0, ip op = nextOp.toString("hex") ip++ switch op when opCodes.inlinePayloadOpCode payload = @decodeString(sequence, ip) ip += payload[0] result.payloadInline = payload[1] when opCodes.nameOpCode payload = @decodeString(sequence, ip) ip += payload[0] result.name = payload[1] when opCodes.keywordsOpCode payload = @decodeString(sequence, ip) ip += payload[0] result.keywords = payload[1] when opCodes.descriptionOpCode payload = @decodeString(sequence, ip) ip += payload[0] result.description = payload[1] when opCodes.uriOpCode payload = @decodeString(sequence, ip) ip += payload[0] result.URI = payload[1] when opCodes.filenameOpCode payload = @decodeString(sequence, ip) ip += payload[0] result.filename = payload[1] when opCodes.attachmentPayloadOpCode payload = @decodeBuffer(sequence, ip) ip += payload[0] result.payloadAttachment = payload[1].toString("hex") when opCodes.payloadMD5OpCode payload = @decodeBytes(sequence, ip, 16) ip += payload[0] result.payloadMD5 = payload[1].toString("hex") when opCodes.payloadSHA1OpCode payload = @decodeBytes(sequence, ip, 20) ip += payload[0] result.payloadSHA1 = payload[1].toString("hex") when opCodes.payloadSHA256OpCode payload = @decodeBytes(sequence, ip, 32) ip += payload[0] result.payloadSHA256 = payload[1].toString("hex") when opCodes.originalCreationDateOpCode result.originalCreationDate = @decodeDate(sequence, ip) ip += 6 when opCodes.lastModifiedDateOpCode result.lastModifiedDate = @decodeDate(sequence, ip) ip += 6; when opCodes.licenseOpCode payload = @decodeString(sequence, ip) ip += payload[0] result.license = payload[1] when opCodes.endSequence running = false result verify: (result)-> errors = [] p = result.payloadAttachment or result.payloadInline; if not p? then return if result.payloadMD5? h = hashBuffer "md5", p if(h.toString("hex") != result.payloadMD5) errors.push("Expected MD5 was #{result.payloadMD5} but the payload MD5 is #{h}") if result.payloadSHA1? h = hashBuffer "sha1", p if(h.toString("hex") != result.payloadSHA1) errors.push("Expected SHA-1 was #{result.payloadSHA1} but the payload SHA-1 is #{h}") if result.payloadSHA256? h = hashBuffer "sha256", p if(h.toString("hex") != result.payloadSHA256) errors.push("Expected SHA-256 was #{result.payloadSHA256} but the payload SHA-256 is #{h}") errors decodeSize: (buffer, ip) -> parseInt @decodeBytes(buffer, ip, 2)[1].toString("hex"), 16 decodeString: (buffer, ip) -> size = @decodeSize(buffer, ip) [size + 2, @decodeBytes(buffer, ip + 2, size)[1].toString("utf-8")] decodeBuffer: (buffer, ip) -> size = decodeSize(buffer, ip) [size + 2, @decodeBytes(buffer, ip+2, size)[1]] decodeBytes: (buffer, ip, length) -> p = new Buffer(length) buffer.copy p, 0, ip [length, p] decodeDate: (buffer, ip) -> buf = new Buffer 6 buffer.copy buf, 0, ip d = new Date parseInt buf.toString("hex"), 16 if exports? exports.LinkSequenceBuilder = module.exports.LinkSequenceBuilder = LinkSequenceBuilder; exports.LinkSequenceEncoder = module.exports.LinkSequenceDecoder = LinkSequenceDecoder; exports.opCodes = module.exports.opCodes = opCodes; exports.decodeBase58 = decodeBase58 exports.encodeBase58 = encodeBase58 exports.bytesToHex = bytesToHex exports.hashBuffer = hashBuffer