client/luascripts/hf_mfu_magicwrite.lua

   1 local cmds = require('commands')
   2 local getopt = require('getopt')
   3 local lib14a = require('read14a')
   4 local utils =  require('utils')
   5 local ansicolors  = require('ansicolors')
   6
   7 -- global
   8 local DEBUG = false -- the debug flag
   9 local bxor = bit32.bxor
  10 local _password = nil
  11 local err_lock = 'use -k or change cfg0 block'
  12
  13 copyright = 'Copyright (c) 2017 IceSQL AB. All rights reserved.'
  14 author = 'Christian Herrmann'
  15 version = 'v1.1.4'
  16 desc = 'This script enables easy programming of a MAGIC NTAG 21* card'
  17 example = [[
  18     -- read magic tag configuration
  19     ]]..ansicolors.yellow..[[script run hf_mfu_magicwrite -c  ]]..ansicolors.reset..[[
  20
  21     -- set uid
  22     ]]..ansicolors.yellow..[[script run hf_mfu_magicwrite -u 04112233445566 ]]..ansicolors.reset..[[
  23
  24     -- set pwd / pack
  25     ]]..ansicolors.yellow..[[script run hf_mfu_magicwrite -p 11223344 -a 8080 ]]..ansicolors.reset..[[
  26
  27     -- set version to NTAG213
  28     ]]..ansicolors.yellow..[[script run hf_mfu_magicwrite -v 0004040201000f03 ]]..ansicolors.reset..[[
  29
  30     -- set signature
  31     ]]..ansicolors.yellow..[[script run hf_mfu_magicwrite -s 1122334455667788990011223344556677889900112233445566778899001122 ]]..ansicolors.reset..[[
  32
  33     -- wipe tag
  34     ]]..ansicolors.yellow..[[script run hf_mfu_magicwrite -w ]]..ansicolors.reset..[[
  35
  36     -- wipe a locked down tag by giving the password
  37     ]]..ansicolors.yellow..[[script run hf_mfu_magicwrite -k ffffffff -w ]]..ansicolors.reset..[[
  38
  39 ]]
  40 usage = [[
  41 script run hf_mfu_magicwrite -h -k <passwd> -c -w -u <uid> -t <type> -p <passwd> -a <pack> -s <signature> -o <otp> -v <version>
  42 ]]
  43 arguments = [[
  44     -h      this help
  45     -c      read magic configuration
  46     -u      UID (14 hexsymbols), set UID on tag
  47     -t      tag type to impersonate
  48                  1 = UL EV1 48b
  49                  2 = UL EV1 128b
  50                  3 = NTAG 210
  51                  4 = NTAG 212
  52                  5 = NTAG 213 (true)
  53                  6 = NTAG 215 (true)
  54                  7 = NTAG 216 (true)
  55                  8 = NTAG I2C 1K
  56                  9 = NTAG I2C 2K
  57                 10 = NTAG I2C 1K PLUS
  58                 11 = NTAG I2C 2K PLUS
  59                 12 = NTAG 213F (true)
  60                 13 = NTAG 216F (true)
  61     -p      password (8 hexsymbols),  set password on tag.
  62     -a      pack ( 4 hexsymbols), set pack on tag.
  63     -s      signature data (64 hexsymbols), set signature data on tag.
  64     -o      OTP data (8 hexsymbols), set `One-Time Programmable` data on tag.
  65     -v      version data (16 hexsymbols), set version data on tag.
  66     -w      wipe tag. You can specify password if the tag has been locked down. Fills tag with zeros and put default values for NTAG213 (like -t 5)
  67     -k      pwd to use with the wipe option
  68 ]]
  69 ---
  70 -- A debug printout-function
  71 local function dbg(args)
  72     if not DEBUG then return end
  73     if type(args) == 'table' then
  74         local i = 1
  75         while result[i] do
  76             dbg(result[i])
  77             i = i+1
  78         end
  79     else
  80         print('###', args)
  81     end
  82 end
  83 -- This is only meant to be used when errors occur
  84 local function oops(err)
  85     print("ERROR: ",err)
  86     core.clearCommandBuffer()
  87     return nil, err
  88 end
  89 ---
  90 -- Usage help
  91 local function help()
  92     print(copyright)
  93     print(author)
  94     print(version)
  95     print(desc)
  96     print(ansicolors.cyan..'Usage'..ansicolors.reset)
  97     print(usage)
  98     print(ansicolors.cyan..'Arguments'..ansicolors.reset)
  99     print(arguments)
 100     print(ansicolors.cyan..'Example usage'..ansicolors.reset)
 101     print(example)
 102 end
 103 ---
 104 -- set the global password variable
 105 local function set_password(pwd)
 106     if pwd == nil then _password = nil; return true, 'Ok' end
 107     if #pwd ~= 8 then return nil, 'password wrong length. Must be 4 hex bytes' end
 108     if #pwd == 0 then _password = nil end
 109     _password = pwd
 110     return true, 'Ok'
 111 end
 112 --- Picks out and displays the data read from a tag
 113 -- Specifically, takes a usb packet, converts to a Command
 114 -- (as in commands.lua), takes the data-array and
 115 -- reads the number of bytes specified in arg1 (arg0 in c-struct)
 116 -- @param usbpacket the data received from the device
 117 local function getResponseData(usbpacket)
 118     local resp = Command.parse(usbpacket)
 119     local len = tonumber(resp.arg1) * 2
 120     return string.sub(tostring(resp.data), 0, len);
 121 end
 122 ---
 123 --
 124 local function sendRaw(rawdata, options)
 125
 126     local flags = lib14a.ISO14A_COMMAND.ISO14A_NO_DISCONNECT
 127                 + lib14a.ISO14A_COMMAND.ISO14A_RAW
 128                 + lib14a.ISO14A_COMMAND.ISO14A_APPEND_CRC
 129
 130     local c = Command:newMIX{cmd = cmds.CMD_HF_ISO14443A_READER,
 131                 arg1 = flags,
 132                 -- arg2 contains the length, which is half the length of the ASCII-string rawdata
 133                 arg2 = string.len(rawdata)/2,
 134                 data = rawdata}
 135
 136     return c:sendMIX(options.ignore_response)
 137 end
 138 ---
 139 --
 140 local function send(payload)
 141     local usb, err = sendRaw(payload,{ignore_response = false})
 142     if err then return oops(err) end
 143     return getResponseData(usb)
 144 end
 145 ---
 146 -- select tag and if password is set, authenticate
 147 local function connect()
 148     core.clearCommandBuffer()
 149
 150     -- First of all, connect
 151     info, err = lib14a.read(true, true)
 152     if err then
 153         lib14a.disconnect()
 154         return oops(err)
 155     end
 156     core.clearCommandBuffer()
 157
 158     --authenticate if needed using global variable
 159     if _password then
 160         send('1B'.._password)
 161     end
 162     return true
 163 end
 164 --
 165 -- Read magic configuration
 166 local function read_config()
 167     local info = connect()
 168     if not info then return false, "Can't select card" end
 169
 170     -- read PWD
 171     local pwd = send("30F0"):sub(1,8)
 172
 173     -- 04 response indicates that blocks has been locked down.
 174     if pwd == '04' then lib14a.disconnect(); return nil, "can't read configuration, "..err_lock end
 175
 176     -- read PACK
 177     local pack = send("30F1"):sub(1,4)
 178
 179     -- read SIGNATURE
 180     local signature1 = send('30F2'):sub(1,32)
 181     local signature2 = send('30F6'):sub(1,32)
 182
 183     -- read VERSION
 184     local version = send('30FA'):sub(1,16)
 185     -- read config
 186     local cardtype = send('30FC'):sub(1,2)
 187
 188     local typestr = ''
 189     if cardtype == '00' then typestr = 'NTAG 213'
 190     elseif cardtype == '01' then typestr = 'NTAG 215'
 191     elseif cardtype == '02' then typestr = 'NTAG 216'
 192     end
 193
 194     local versionstr = 'unknown'
 195     if version == '0004030101000B03' then versionstr = 'UL EV1 48b'
 196     elseif version == '0004030101000E03' then versionstr = 'UL EV1 128b'
 197     elseif version == '0004040101000B03' then versionstr = 'NTAG 210'
 198     elseif version == '0004040101000E03' then versionstr = 'NTAG 212'
 199     elseif version == '0004040201000F03' then versionstr = 'NTAG 213'
 200     elseif version == '0004040201001103' then versionstr = 'NTAG 215'
 201     elseif version == '0004040201001303' then versionstr = 'NTAG 216'
 202     elseif version == '0004040502011303' then versionstr = 'NTAG I2C 1K'
 203     elseif version == '0004040502011503' then versionstr = 'NTAG I2C 2K'
 204     elseif version == '0004040502021303' then versionstr = 'NTAG I2C 1K PLUS'
 205     elseif version == '0004040502021503' then versionstr = 'NTAG I2C 2K PLUS'
 206     elseif version == '0004040401000F03' then versionstr = 'NTAG 213F'
 207     elseif version == '0004040401001303' then versionstr = 'NTAG 216F'
 208     end
 209
 210     print('Magic NTAG 21* Configuration')
 211     print(' - Type    ', typestr, '(genuine cardtype)')
 212     print(' - Password', pwd)
 213     print(' - Pack    ', pack)
 214     print(' - Version ', version, '(' .. versionstr .. ')')
 215     print(' - Signature', signature1..signature2)
 216
 217     lib14a.disconnect()
 218     return true, 'Ok'
 219 end
 220 ---
 221 -- Write SIGNATURE data
 222 local function write_signature(data)
 223
 224     -- uid string checks
 225     if data == nil then return nil, 'empty data string' end
 226     if #data == 0 then return nil, 'empty data string' end
 227     if #data ~= 64 then return nil, 'data wrong length. Should be 32 hex bytes' end
 228
 229     local info = connect()
 230     if not info then return false, "Can't select card" end
 231
 232     print('Writing new signature')
 233
 234     local b,c
 235     local cmd = 'A2F%d%s'
 236     local j = 2
 237     for i = 1, #data, 8 do
 238         b = data:sub(i,i+7)
 239         c = cmd:format(j,b)
 240         local resp = send(c)
 241         if resp == '04' then lib14a.disconnect(); return nil, 'Failed to write signature' end
 242         j = j + 1
 243     end
 244     lib14a.disconnect()
 245     return true, 'Ok'
 246 end
 247 ---
 248 -- Write PWD
 249 local function write_pwd(pwd)
 250     -- PWD string checks
 251     if pwd == nil then return nil, 'empty PWD string' end
 252     if #pwd == 0 then return nil, 'empty PWD string' end
 253     if #pwd ~= 8 then return nil, 'PWD wrong length. Should be 4 hex bytes' end
 254
 255     local info = connect()
 256     if not info then return false, "Can't select card" end
 257
 258     print('Writing new PWD ', pwd)
 259
 260     local resp = send('A2F0'..pwd)
 261     lib14a.disconnect()
 262     if resp == '04' then
 263         return nil, 'Failed to write password'
 264     else
 265         return true, 'Ok'
 266     end
 267 end
 268 ---
 269 -- Write PACK
 270 local function write_pack(pack)
 271     -- PACK string checks
 272     if pack == nil then return nil, 'empty PACK string' end
 273     if #pack == 0 then return nil, 'empty PACK string' end
 274     if #pack ~= 4 then return nil, 'PACK wrong length. Should be 4 hex bytes' end
 275
 276     local info = connect()
 277     if not info then return false, "Can't select card" end
 278
 279     print('Writing new PACK', pack)
 280
 281     local resp = send('A2F1'..pack..'0000')
 282     lib14a.disconnect()
 283     if resp == '04' then
 284         return nil, 'Failed to write pack'
 285     else
 286         return true, 'Ok'
 287     end
 288 end
 289 --
 290 -- Write OTP block
 291 local function write_otp(block3)
 292
 293     -- OTP string checks
 294     if block3 == nil then return nil, 'empty OTP string' end
 295     if #block3 == 0 then return nil, 'empty OTP string' end
 296     if #block3 ~= 8 then return nil, 'OTP wrong length. Should be 4 hex bytes' end
 297
 298     local info = connect()
 299     if not info then return false, "Can't select card" end
 300
 301     print('Writing new OTP ', block3)
 302
 303     local resp = send('A203'..block3)
 304     lib14a.disconnect()
 305     if resp == '04' then
 306         return nil, 'Failed to write OTP'
 307     else
 308         return true, 'Ok'
 309     end
 310 end
 311 --
 312 -- Writes a UID with bcc1, bcc2.  Needs a magic tag.
 313 local function write_uid(uid)
 314     -- uid string checks
 315     if uid == nil then return nil, 'empty uid string' end
 316     if #uid == 0 then return nil, 'empty uid string' end
 317     if #uid ~= 14 then return nil, 'uid wrong length. Should be 7 hex bytes' end
 318
 319     local info = connect()
 320     if not info then return false, "Can't select card" end
 321
 322     print('Writing new UID ', uid)
 323
 324     local uidbytes = utils.ConvertHexToBytes(uid)
 325     local bcc1 = bxor(bxor(bxor(uidbytes[1], uidbytes[2]), uidbytes[3]), 0x88)
 326     local bcc2 = bxor(bxor(bxor(uidbytes[4], uidbytes[5]), uidbytes[6]), uidbytes[7])
 327     local block0 = string.format('%02X%02X%02X%02X', uidbytes[1], uidbytes[2], uidbytes[3], bcc1)
 328     local block1 = string.format('%02X%02X%02X%02X', uidbytes[4], uidbytes[5], uidbytes[6], uidbytes[7])
 329     local block2 = string.format('%02X%02X%02X%02X', bcc2, 0x48, 0x00, 0x00)
 330     local resp
 331
 332     resp = send('A200'..block0)
 333     resp = send('A201'..block1)
 334     resp = send('A202'..block2)
 335     lib14a.disconnect()
 336
 337     if resp == '04' then
 338         return nil, 'Failed to write new uid'
 339     else
 340         return true, 'Ok'
 341     end
 342 end
 343 ---
 344 -- Write VERSION data,
 345 -- make sure you have correct version data
 346 local function write_version(data)
 347     -- version string checks
 348     if data == nil then return nil, 'empty version string' end
 349     if #data == 0 then return nil, 'empty version string' end
 350     if #data ~= 16 then return nil, 'version wrong length. Should be 8 hex bytes' end
 351
 352     local info = connect()
 353     if not info then return false, "Can't select card" end
 354
 355     print('Writing new version', data)
 356
 357     local b1 = data:sub(1,8)
 358     local b2 = data:sub(9,16)
 359     local resp
 360     resp = send('A2FA'..b1)
 361     resp = send('A2FB'..b2)
 362     lib14a.disconnect()
 363     if resp == '04' then
 364         return nil, 'Failed to write version'
 365     else
 366         return true, 'Ok'
 367     end
 368 end
 369 ---
 370 -- write TYPE which card is based on.
 371 -- 00 = 213,  01 = 215, 02 = 216
 372 local function write_type(data)
 373     -- type string checks
 374     if data == nil then return nil, 'empty type string' end
 375     if #data == 0 then return nil, 'empty type string' end
 376     if #data ~= 2 then return nil, 'type wrong length. Should be 1 hex byte' end
 377
 378     local info = connect()
 379     if not info then return false, "Can't select card" end
 380     print('Writing new type', data)
 381
 382     local resp = send('A2FC'..data..'000000')
 383     lib14a.disconnect()
 384     if resp == '04' then
 385         return nil, 'Failed to write type'
 386     else
 387         return true, 'Ok'
 388     end
 389 end
 390 ---
 391 -- Set tag type.  Predefinde version data together with magic type set.
 392 -- Since cmd always gives 10 bytes len (data+crc) we can impersonate the following types
 393 -- we only truly be three types NTAG 213,215 and 216
 394 local function set_type(tagtype)
 395
 396     -- tagtype checks
 397     if type(tagtype) == 'string' then tagtype = tonumber(tagtype, 10) end
 398     if tagtype == nil then return nil, 'empty tagtype' end
 399
 400     if tagtype == 1 then
 401         print('Setting: UL-EV1 48')
 402         write_otp('00000000')               -- Setting OTP to default 00 00 00 00
 403         write_version('0004030101000b03')   -- UL-EV1 (48) 00 04 03 01 01 00 0b 03
 404         write_type('00')                    -- based on NTAG213..
 405
 406         -- Setting UL-Ev1 default config bl 16,17
 407         connect()
 408         send('a210000000FF')
 409         send('a21100050000')
 410
 411     elseif tagtype == 2 then
 412         print('Setting: UL-EV1 128')
 413         write_otp('00000000')               -- Setting OTP to default 00 00 00 00
 414         write_version('0004030101000e03')   -- UL-EV1 (128) 00 04 03 01 01 00 0e 03
 415         write_type('01')
 416
 417         -- Setting UL-Ev1 default config bl 37,38
 418         connect()
 419         send('a225000000FF')
 420         send('a22600050000')
 421     elseif tagtype == 3 then
 422         print('Setting: NTAG 210')
 423         write_version('0004040101000b03')   -- NTAG210 00 04 04 01 01 00 0b 03
 424         write_type('00')
 425
 426         -- Setting NTAG210 default CC block456
 427         connect()
 428         send('a203e1100600')
 429         send('a2040300fe00')
 430         send('a20500000000')
 431         -- Setting  cfg1/cfg2
 432         send('a210000000FF')
 433         send('a21100050000')
 434     elseif tagtype == 4 then
 435         print('Setting: NTAG 212')
 436         write_version('0004040101000E03')   -- NTAG212 00 04 04 01 01 00 0E 03
 437         write_type('00')
 438
 439         -- Setting NTAG212 default CC block456
 440         connect()
 441         send('a203e1101000')
 442         send('a2040103900a')
 443         send('a205340300fe')
 444         -- Setting  cfg1/cfg2
 445         send('a225000000FF')
 446         send('a22600050000')
 447     elseif tagtype == 5 then
 448         print('Setting: NTAG 213')
 449         write_version('0004040201000F03')       -- NTAG213 00 04 04 02 01 00 0f 03
 450         write_type('00')
 451
 452         -- Setting NTAG213 default CC block456
 453         connect()
 454         send('a203e1101200')
 455         send('a2040103a00c')
 456         send('a205340300fe')
 457         -- setting cfg1/cfg2
 458         send('a229000000ff')
 459         send('a22a00050000')
 460     elseif tagtype == 6 then
 461         print('Setting: NTAG 215')
 462         write_version('0004040201001103')       -- NTAG215 00 04 04 02 01 00 11 03
 463         write_type('01')
 464
 465         -- Setting NTAG215 default CC block456
 466         connect()
 467         send('a203e1103e00')
 468         send('a2040300fe00')
 469         send('a20500000000')
 470         -- setting cfg1/cfg2
 471         send('a283000000ff')
 472         send('a28400050000')
 473     elseif tagtype == 7 then
 474         print('Setting: NTAG 216')
 475         write_version('0004040201001303')       -- NTAG216 00 04 04 02 01 00 13 03
 476         write_type('02')
 477
 478         -- Setting NTAG216 default CC block456
 479         connect()
 480         send('a203e1106d00')
 481         send('a2040300fe00')
 482         send('a20500000000')
 483         -- setting cfg1/cfg2
 484         send('a2e3000000ff')
 485         send('a2e400050000')
 486     elseif tagtype == 8 then
 487         print('Setting: NTAG I2C 1K')
 488         write_version('0004040502011303')       -- NTAG_I2C_1K 00 04 04 05 02 01 13 03
 489         write_type('02')
 490
 491         -- Setting NTAG I2C 1K default CC block456
 492         connect()
 493         send('a203e1106D00')
 494         send('a2040300fe00')
 495         send('a20500000000')
 496     elseif tagtype == 9 then
 497         print('Setting: NTAG I2C 2K')
 498         write_version('0004040502011503')       -- NTAG_I2C_2K 00 04 04 05 02 01 15 03
 499         write_type('02')
 500
 501         -- Setting NTAG I2C 2K default CC block456
 502         connect()
 503         send('a203e110EA00')
 504         send('a2040300fe00')
 505         send('a20500000000')
 506     elseif tagtype == 10 then
 507         print('Setting: NTAG I2C plus 1K')
 508         write_version('0004040502021303')       -- NTAG_I2C_1K 00 04 04 05 02 02 13 03
 509         write_type('02')
 510
 511         -- Setting NTAG I2C 1K default CC block456
 512         connect()
 513         send('a203e1106D00')
 514         send('a2040300fe00')
 515         send('a20500000000')
 516     elseif tagtype == 11 then
 517         print('Setting: NTAG I2C plus 2K')
 518         write_version('0004040502021503')       -- NTAG_I2C_2K 00 04 04 05 02 02 15 03
 519         write_type('02')
 520
 521         -- Setting NTAG I2C 2K default CC block456
 522         connect()
 523         send('a203e1106D00')
 524         send('a2040300fe00')
 525         send('a20500000000')
 526     elseif tagtype == 12 then
 527         print('Setting: NTAG 213F')
 528         write_version('0004040401000F03')       -- NTAG213F 00 04 04 04 01 00 0f 03
 529         write_type('00')
 530
 531         -- Setting NTAG213 default CC block456
 532         connect()
 533         send('a203e1101200')
 534         send('a2040103a00c')
 535         send('a205340300fe')
 536         -- setting cfg1/cfg2
 537         send('a229000000ff')
 538         send('a22a00050000')
 539     elseif tagtype == 13 then
 540         print('Setting: NTAG 216F')
 541         write_version('0004040401001303')       -- NTAG216F 00 04 04 04 01 00 13 03
 542         write_type('02')
 543
 544         -- Setting NTAG216 default CC block456
 545         connect()
 546         send('a203e1106d00')
 547         send('a2040300fe00')
 548         send('a20500000000')
 549         -- setting cfg1/cfg2
 550         send('a2e3000000ff')
 551         send('a2e400050000')
 552     end
 553
 554     lib14a.disconnect()
 555     if resp == '04' then
 556         return nil, 'Failed to set type'
 557     else
 558         return true, 'Ok'
 559     end
 560 end
 561 ---
 562 -- wipe tag
 563 local function wipe()
 564
 565     local info = connect()
 566     if not info then return false, "Can't select card" end
 567
 568     local err, msg, resp
 569     local cmd_empty = 'A2%02X00000000'
 570     local cmd_cfg1  = 'A2%02X000000FF'
 571     local cmd_cfg2  = 'A2%02X00050000'
 572
 573     print('Wiping tag')
 574
 575     for b = 3, 0xFB do
 576         --configuration block 0
 577         if b == 0x29 or b == 0x83 or b == 0xe3 then
 578             local cmd = (cmd_cfg1):format(b)
 579             resp = send(cmd)
 580         --configuration block 1
 581         elseif b == 0x2a or b == 0x84 or b == 0xe4 then
 582             local cmd = (cmd_cfg2):format(b)
 583             resp = send(cmd)
 584         else
 585             resp = send(cmd_empty:format(b))
 586         end
 587         if resp == '04' or #resp == 0 then
 588             io.write('\nwrote block '..b, ' failed\n')
 589             err = true
 590         else
 591             io.write('.')
 592         end
 593         io.flush()
 594     end
 595     io.write('\r\n')
 596
 597     lib14a.disconnect()
 598
 599     if err then return nil, "Tag locked down, "..err_lock end
 600
 601     print('setting default values...')
 602
 603     set_password(nil)
 604
 605     -- set NTAG213 default values
 606     err, msg = set_type(5)
 607     if err == nil then return err, msg end
 608
 609     --set UID
 610     err, msg = write_uid('04112233445566')
 611     if err == nil then return err, msg end
 612
 613     --set pwd
 614     err, msg = write_pwd('FFFFFFFF')
 615     if err == nil then return err, msg end
 616
 617     --set pack
 618     err, msg = write_pack('0000')
 619     if err == nil then return err, msg end
 620
 621     return true, 'Ok'
 622 end
 623 ---
 624 -- The main entry point
 625 function main(args)
 626
 627     print( string.rep('--',20) )
 628     print( string.rep('--',20) )
 629     print()
 630
 631     local err, msg
 632
 633     if #args == 0 then return help() end
 634
 635     -- Read the parameters
 636     for o, a in getopt.getopt(args, 'hck:u:t:p:a:s:o:v:w') do
 637
 638         -- help
 639         if o == "h" then return help() end
 640
 641         --key
 642         if o == 'k' then err, msg = set_password(a) end
 643
 644         -- configuration
 645         if o == "c" then err, msg = read_config() end
 646
 647         --wipe tag
 648         if o == "w" then err, msg = wipe() end
 649
 650         -- write uid
 651         if o == "u" then err, msg = write_uid(a) end
 652
 653         -- write type/version
 654         if o == "t" then err, msg = set_type(a) end
 655
 656         -- write pwd
 657         if o == "p" then err, msg = write_pwd(a) end
 658
 659         -- write pack
 660         if o == "a" then err, msg = write_pack(a) end
 661
 662         -- write signature
 663         if o == "s" then err, msg = write_signature(a) end
 664
 665         -- write otp
 666         if o == "o" then err, msg = write_otp(a) end
 667
 668         -- write version
 669         if o == "v" then err, msg = write_version(a) end
 670
 671         if err == nil then return oops(msg) end
 672     end
 673
 674 end
 675
 676 main(args)