"errno.WITNESS_UNEXPECTED" error while trying to get signatures

[yakitorifoodie]

This issue persists if a segwit or a transaction with more than one inputs were given.

Log:

vb@h2o:~# tx -s 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 Traceback (most recent call last): File "/usr/local/bin/tx", line 11, in <module> load_entry_point('pycoin==0.0.0', 'console_scripts', 'tx')() File "/usr/local/lib/python3.6/dist-packages/pycoin-0.0.0-py3.6.egg/pycoin/cmds/tx.py", line 710, in main tx(args, parser) File "/usr/local/lib/python3.6/dist-packages/pycoin-0.0.0-py3.6.egg/pycoin/cmds/tx.py", line 686, in tx args.verbose_signature, args.disassemble, args.trace, args.pdb) File "/usr/local/lib/python3.6/dist-packages/pycoin-0.0.0-py3.6.egg/pycoin/cmds/tx.py", line 569, in print_output dump_tx(output, tx, network, verbose_signature, disassembly_level, trace, pdb) File "/usr/local/lib/python3.6/dist-packages/pycoin-0.0.0-py3.6.egg/pycoin/cmds/dump.py", line 120, in dump_tx dump_inputs(output, tx, network, verbose_signature, traceback_f, disassembly_level) File "/usr/local/lib/python3.6/dist-packages/pycoin-0.0.0-py3.6.egg/pycoin/cmds/dump.py", line 72, in dump_inputs dump_signatures(output, tx, tx_in, tx_out, idx, network, traceback_f) File "/usr/local/lib/python3.6/dist-packages/pycoin-0.0.0-py3.6.egg/pycoin/cmds/dump.py", line 88, in dump_signatures signatures = [parse_signature_blob(blob) for blob, sig_hash in network.who_signed.extract_signatures(tx, idx)] File "/usr/local/lib/python3.6/dist-packages/pycoin-0.0.0-py3.6.egg/pycoin/cmds/dump.py", line 88, in <listcomp> signatures = [parse_signature_blob(blob) for blob, sig_hash in network.who_signed.extract_signatures(tx, idx)] File "/usr/local/lib/python3.6/dist-packages/pycoin-0.0.0-py3.6.egg/pycoin/contrib/who_signed.py", line 33, in extract_signatures for puzzle_script, solution_stack, flags, sighash_f in sc.puzzle_and_solution_iterator(tx_context): File "/usr/local/lib/python3.6/dist-packages/pycoin-0.0.0-py3.6.egg/pycoin/coins/bitcoin/SolutionChecker.py", line 215, in puzzle_and_solution_iterator witness_tuple = self.witness_program_tuple(tx_context, puzzle_script, solution_stack, flags, is_p2sh) File "/usr/local/lib/python3.6/dist-packages/pycoin-0.0.0-py3.6.egg/pycoin/coins/bitcoin/SegwitChecker.py", line 144, in witness_program_tuple raise ScriptError("witness unexpected", errno.WITNESS_UNEXPECTED) pycoin.coins.SolutionChecker.ScriptError: ('witness unexpected', 39)

[richardkiss]

There is definitely a bug here, but I'm not sure exactly what it is. You can work around it by adding -a, which will fetch the source transaction from block explorers (see the README for PYCOIN_BTC_PROVIDERS). Example:

% tx -a -s 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
warning: transaction fees recommendations casually calculated and estimates may be incorrect
warning: transaction fee lower than (casually calculated) expected value of 0.10000 mBTC, transaction might not propogate
Version:  1  tx hash 05f5f11bda9fbef31a6be64a50e5f27f31dcd132c524f3bbc95121d61c763ea6  341 bytes
      segwit tx hash d5a8a5556071abcc149afa1a1038d09f6c44aecbc4741bfa77edaa087a71dda7
TxIn count: 2; TxOut count: 1
Lock time: 0 (valid anytime)
Inputs:
   0: bc1qsezkmvg63r8w9s6c3mmr9tf9cm5s4mx7tkdagt from 34903cdedcc337347f28cd403c4d65fc31d68a64169c8307adeddaf415523285:0         1.37200 mBTC  sig ok
      r: 0x4748ea5502f7561eed5494b95f0545ae4b05ed40d32f5169d6385df0a1ea54e6
      s: 0x52fe070b165d7cde86aba2d7ca72996d10ba9d304521088b34015bcd59c8bec0
      z: 0xd0dba1caf3f40d30019f358bd7a1cc0d715c7d03b2451cb44d8390d67240a668 SIGHASH_ALL
   1: 1Fmma8inqay1y7CLibp6FcBFxNnVbkLDSf from 2d409e62e4f549114fef689f97fdf1fec6319a69a61f152498dea79ca083e702:0        10.70018 mBTC  sig ok
      r: 0x917eef11069fcf2be24dd55c29bb9d5e30b10eeb812be1024a5a404d80d7a51c
      s: 0x293952a6d8b80c2db98e2575ddd00a591115161e33853652fde5cbc58e4488c4
      z: 0xd09537d881d2058def18c2ab6f291e0be27adbe1fb3c7f4f0f0aa03ec9f7307a SIGHASH_ALL
Output:
   0: 37XJ1RPN9q7T9yxbbcH5eq2c6rqLxqsHbD receives     12.02318 mBTC
Total input      12.07218 mBTC
Total output     12.02318 mBTC
Total fees        0.04900 mBTC
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
all incoming transaction values validated

(There is a known bug affecting segwit that means the z-values above are probably incorrect.)

[yakitorifoodie]

thank you very much for addressing the issue.

[richardkiss]

I'm going to reopen as a reminder to improve this error case.