{trim,strip,katch,bufeq_fast,uint_to_buffer} = require './util' #========================================================================= make_line = (x = "") -> "#{x}\n" #========================================================================= exports.Encoder = class Encoder constructor : (@C) -> #------ frame : (t) -> dash = ("-" for i in [0...5]).join('') return { begin : make_line(dash + "BEGIN PGP #{t}" + dash) end : make_line(dash + "END PGP #{t}" + dash) } #------ b64e : (d) -> raw = d.toString 'base64' w = 64 parts = for i in [0...raw.length] by w end = Math.min(i+w,raw.length) raw[i...end] make_line parts.join("\n") #------ header : () -> (make_line(x) for x in [ "Version: #{@C.header.version}", "Comment: #{@C.header.comment}" ]).join '' #------ encode : (type, data) -> f = @frame type f.begin.concat(@header(), make_line(), @b64e(data), formatCheckSum(data), f.end) #========================================================================= # # Make a clearsign header for the first part of the clearsign message. # # @param {Object} C the constants object # @param {String} data the message data, should end with a newline # @param {String} hasher_name the name of the hash function used for the signature (e.g. 'SHA512') # @return {String} the framed message exports.clearsign_header = clearsign = (C, data, hasher_name) -> enc = new Encoder C f = enc.frame("SIGNED MESSAGE").begin f.concat(make_line("Hash: #{hasher_name}"), make_line(), data) #========================================================================= exports.encode = encode = (C, type, data) -> (new Encoder C).encode(type, data) #========================================================================= # # Internal function to calculate a CRC-24 checksum over a given string (data) # @param {Buffer} data Data to create a CRC-24 checksum for # @return {Integer} The CRC-24 checksum as number # crc_table = [ 0x00000000, 0x00864cfb, 0x018ad50d, 0x010c99f6, 0x0393e6e1, 0x0315aa1a, 0x021933ec, 0x029f7f17, 0x07a18139, 0x0727cdc2, 0x062b5434, 0x06ad18cf, 0x043267d8, 0x04b42b23, 0x05b8b2d5, 0x053efe2e, 0x0fc54e89, 0x0f430272, 0x0e4f9b84, 0x0ec9d77f, 0x0c56a868, 0x0cd0e493, 0x0ddc7d65, 0x0d5a319e, 0x0864cfb0, 0x08e2834b, 0x09ee1abd, 0x09685646, 0x0bf72951, 0x0b7165aa, 0x0a7dfc5c, 0x0afbb0a7, 0x1f0cd1e9, 0x1f8a9d12, 0x1e8604e4, 0x1e00481f, 0x1c9f3708, 0x1c197bf3, 0x1d15e205, 0x1d93aefe, 0x18ad50d0, 0x182b1c2b, 0x192785dd, 0x19a1c926, 0x1b3eb631, 0x1bb8faca, 0x1ab4633c, 0x1a322fc7, 0x10c99f60, 0x104fd39b, 0x11434a6d, 0x11c50696, 0x135a7981, 0x13dc357a, 0x12d0ac8c, 0x1256e077, 0x17681e59, 0x17ee52a2, 0x16e2cb54, 0x166487af, 0x14fbf8b8, 0x147db443, 0x15712db5, 0x15f7614e, 0x3e19a3d2, 0x3e9fef29, 0x3f9376df, 0x3f153a24, 0x3d8a4533, 0x3d0c09c8, 0x3c00903e, 0x3c86dcc5, 0x39b822eb, 0x393e6e10, 0x3832f7e6, 0x38b4bb1d, 0x3a2bc40a, 0x3aad88f1, 0x3ba11107, 0x3b275dfc, 0x31dced5b, 0x315aa1a0, 0x30563856, 0x30d074ad, 0x324f0bba, 0x32c94741, 0x33c5deb7, 0x3343924c, 0x367d6c62, 0x36fb2099, 0x37f7b96f, 0x3771f594, 0x35ee8a83, 0x3568c678, 0x34645f8e, 0x34e21375, 0x2115723b, 0x21933ec0, 0x209fa736, 0x2019ebcd, 0x228694da, 0x2200d821, 0x230c41d7, 0x238a0d2c, 0x26b4f302, 0x2632bff9, 0x273e260f, 0x27b86af4, 0x252715e3, 0x25a15918, 0x24adc0ee, 0x242b8c15, 0x2ed03cb2, 0x2e567049, 0x2f5ae9bf, 0x2fdca544, 0x2d43da53, 0x2dc596a8, 0x2cc90f5e, 0x2c4f43a5, 0x2971bd8b, 0x29f7f170, 0x28fb6886, 0x287d247d, 0x2ae25b6a, 0x2a641791, 0x2b688e67, 0x2beec29c, 0x7c3347a4, 0x7cb50b5f, 0x7db992a9, 0x7d3fde52, 0x7fa0a145, 0x7f26edbe, 0x7e2a7448, 0x7eac38b3, 0x7b92c69d, 0x7b148a66, 0x7a181390, 0x7a9e5f6b, 0x7801207c, 0x78876c87, 0x798bf571, 0x790db98a, 0x73f6092d, 0x737045d6, 0x727cdc20, 0x72fa90db, 0x7065efcc, 0x70e3a337, 0x71ef3ac1, 0x7169763a, 0x74578814, 0x74d1c4ef, 0x75dd5d19, 0x755b11e2, 0x77c46ef5, 0x7742220e, 0x764ebbf8, 0x76c8f703, 0x633f964d, 0x63b9dab6, 0x62b54340, 0x62330fbb, 0x60ac70ac, 0x602a3c57, 0x6126a5a1, 0x61a0e95a, 0x649e1774, 0x64185b8f, 0x6514c279, 0x65928e82, 0x670df195, 0x678bbd6e, 0x66872498, 0x66016863, 0x6cfad8c4, 0x6c7c943f, 0x6d700dc9, 0x6df64132, 0x6f693e25, 0x6fef72de, 0x6ee3eb28, 0x6e65a7d3, 0x6b5b59fd, 0x6bdd1506, 0x6ad18cf0, 0x6a57c00b, 0x68c8bf1c, 0x684ef3e7, 0x69426a11, 0x69c426ea, 0x422ae476, 0x42aca88d, 0x43a0317b, 0x43267d80, 0x41b90297, 0x413f4e6c, 0x4033d79a, 0x40b59b61, 0x458b654f, 0x450d29b4, 0x4401b042, 0x4487fcb9, 0x461883ae, 0x469ecf55, 0x479256a3, 0x47141a58, 0x4defaaff, 0x4d69e604, 0x4c657ff2, 0x4ce33309, 0x4e7c4c1e, 0x4efa00e5, 0x4ff69913, 0x4f70d5e8, 0x4a4e2bc6, 0x4ac8673d, 0x4bc4fecb, 0x4b42b230, 0x49ddcd27, 0x495b81dc, 0x4857182a, 0x48d154d1, 0x5d26359f, 0x5da07964, 0x5cace092, 0x5c2aac69, 0x5eb5d37e, 0x5e339f85, 0x5f3f0673, 0x5fb94a88, 0x5a87b4a6, 0x5a01f85d, 0x5b0d61ab, 0x5b8b2d50, 0x59145247, 0x59921ebc, 0x589e874a, 0x5818cbb1, 0x52e37b16, 0x526537ed, 0x5369ae1b, 0x53efe2e0, 0x51709df7, 0x51f6d10c, 0x50fa48fa, 0x507c0401, 0x5542fa2f, 0x55c4b6d4, 0x54c82f22, 0x544e63d9, 0x56d11cce, 0x56575035, 0x575bc9c3, 0x57dd8538 ] #----- compute_crc24 = (input, initval = 0xB704CE) -> crc = initval index = 0 while ((input.length - index) > 16) crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 0)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 1)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 2)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 3)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 4)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 5)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 6)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 7)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 8)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 9)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 10)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 11)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 12)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 13)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 14)) & 0xff] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index + 15)) & 0xff] index += 16 for j in [index...input.length] crc = (crc << 8) ^ crc_table[((crc >> 16) ^ input.readUInt8(index++)) & 0xff] return crc & 0xffffff #========================================================================= # # Calculates a checksum over the given data and returns it base64 encoded # @param {Buffer} data Data to create a CRC-24 checksum for # @return {Buffer} Base64 encoded checksum # getCheckSum = (data,pad) -> ret = crc24_to_base64(compute_crc24(data),pad) ret exports.crc24_to_base64 = crc24_to_base64 = (c, pad = true) -> (if pad then "=" else '') + uint_to_buffer(32, c)[1...4].toString('base64') formatCheckSum = (data) -> make_line(getCheckSum(data,true)) # Calculates the checksum over the given data and compares it with the # given base64 encoded checksum # @param {String} data Data to create a CRC-24 checksum for # @param {String} checksum Base64 encoded checksum # @return {Boolean} True if the given checksum is correct; otherwise false # verifyCheckSum = (data, checksum) -> (getCheckSum(data,false) is checksum) #========================================================================= exports.Message = class Message constructor : ({@body, @type, @comment, @version, @pre, @post}) -> @lines = [] @fields = {} @payload = null unsplit : (lines) -> lines.join "\n" raw : -> @unsplit(@lines) finish_unframe : ({pre,post}) -> @pre = @unsplit(pre) @post = @unsplit(post) if @clearsign? @clearsign.body = @unsplit(@clearsign.lines) make_clearsign : () -> @clearsign = headers : {} lines : [] body : null #========================================================================= exports.Parser = class Parser constructor : (data, {@strict} = {}) -> @init data init : (data) -> @data = if Buffer.isBuffer data then data.toString('utf8') else data @lines = @data.split /\r?\n/ @checksum = null @body = null @type = null @ret = null @last_type = null parse : () -> @ret = new Message {} @unframe() @check_charset() @pop_headers() @parse_type() @strip_empties_in_footer() @verify_base64_lines() if @strict @trim_lines() @find_checksum() @read_body() @check_checksum() @ret #----- # Subclasses can make this smarter. parse_type : () -> @ret.type = @ret.fields.type = @type #----- last_line : () -> @payload[-1...][0] #----- mparse : () -> out = [] go = true while go @skip() if @lines.length obj = @parse() out.push obj @init obj.post else go = false out #----- skip : () -> while @lines.length if @lines[0].match /\S+/ then break @lines.shift() #----- read_body : () -> @ret.payload = @payload.join("\n") dat = @payload.join '' @ret.body = Buffer.from dat, 'base64' #----- check_checksum : () -> @ret.fields.checksum = @checksum if @checksum? and not verifyCheckSum @ret.body, @checksum throw new Error "checksum mismatch" #----- pop_headers : () -> while @payload.length l = @payload.shift() if (m = l.match /^Version: (.*)/) then @ret.version = m[1] else if (m = l.match /^Comment: (.*)/)? then @ret.comment = m[1] else if (not l? or (l.length is 0) or (l.match /^\s+$/)) then break else if l.match /^\S+: .+$/ then # ignored pseudo-header else throw new Error "bad PGP armor found; expected a newline" #----- strip_empties_in_footer : () -> @payload.pop() while @last_line()?.match(/^\s*$/) #----- verify_base64_lines : () -> rxx_b64 = /^[a-zA-Z0-9\/+=]+$/ max_line_length = 80 for line in @payload unless line.match rxx_b64 throw new Error "line \"#{line}\" has characters that are not part of base64" if line.length > max_line_length throw new Error "armor line longer than #{max_line_length} characters" #----- trim_lines : () -> @payload = (trim(p) for p in @payload) #----- find_checksum : () -> @checksum = @payload.pop()[1...] if (l = @last_line())? and l[0] is '=' #----- v_unframe : (pre) -> true #----- unframe : () -> rxx_b = /^(-{5}BEGIN PGP (.*?)-{5}\s*$)/ rxx_e = /^(-{5}END PGP (.*?)-{5})(.*)$/m rxx = rxx_b payload = [] stage = 0 type = null ret = null go = true pre = [] post = [] found_pre_std = (l, is_last) -> pre.push l found_pre_clearsign = (l, is_last) => @ret.clearsign.lines.push l found_pre = found_pre_std while @lines.length and go line = @lines.shift() switch stage when -1 if (m = line.match /^([^:]+): (.*)$/) @ret.clearsign.headers[m[1].toLowerCase()] = m[2] else if line.match /^\s*$/ stage++ found_pre = found_pre_clearsign else throw new Error "Bad line in clearsign header" @ret.lines.push line when 0 if (m = line.match rxx_b)? found_pre '', true @ret.lines.push (if @ret.clearsign then line else m[1]) @type = m[2] unless @type? @last_type = m[2] if m[2] is "SIGNED MESSAGE" stage-- @ret.make_clearsign() else stage++ else @ret.lines.push line if @ret.clearsign found_pre line, false when 1 if (m = line.match rxx_e) @ret.lines.push m[1] if m[2] isnt @last_type throw new Error "type mismatch -- begin #{@last_type} w/ end #{m[1]}" stage++ post = [ m[3] ].concat @lines @lines = [] go = false else @ret.lines.push line payload.push line if stage is 0 then throw new Error "no header found" else if stage is 1 then throw new Error "no tailer found" else @payload = payload @ret.finish_unframe { pre, post } #----- check_charset : () -> # Only allow low printable characters, unless the message is clearsigned. # This aligns with the spirit if not the letter of armoring in rfc4880 # "the whole point of armoring is to provide seven-bit-clean data" if not @ret.clearsign? and not /^[\n\r\t\x20-\x7e]*$/.test @data throw new Error "invalid character in armor" #========================================================================= # # Decode armor64-ed data, including header framing, checksums, etc. # # @param {String} data The data to decode. Alternatively, you can provide # a Buffer, and we'll output utf8 string out of it. # @return {Array<{Error},{Buffer}>} And error or a buffer if success. # exports.decode = decode = (data) -> katch () -> (new Parser data).parse() exports.mdecode = decode = (data) -> katch () -> (new Parser data).mparse() #========================================================================= exports.compute_crc24 = compute_crc24 #=========================================================================