deaa6dd144 psbt: check output index is within bounds before accessing (Andrew Chow)
f1ef7f0aa4 Don't calculate tx fees for PSBTs with invalid money values (Andrew Chow)
Pull request description:
Fixes#17149
Two classes of issues were found by the psbt fuzzer: values out of range and causing overflows, and prevout indexes being out of range. This PR fixes both.
When accessing a specific output using the index given in the tx, check that it is actually a possible output before trying to access the output.
When summing and checking amounts for `decodepsbt` and `analyzepsbt`, make sure that the values are actually valid money values.. Otherwise, stop summing and don't show the fee. For `analyzepsbt`, return that the next role is the Creator since the Creator needs to remake the transaction to be valid.
ACKs for top commit:
practicalswift:
ACK deaa6dd144 -- only change since last ACK was the addition of tests
gwillen:
tested ACK deaa6dd, would also like to see this merged!
Tree-SHA512: 06c36720bbb5a7ab1c29f7d15878bf9f0d3e5760c06bff479d412e1bf07bb3e0e9ab6cca820a4bfedaab71bfd7af813807e87cbcdf0af25cc3f66a53a06dbcfd
In decodepsbt if an invalid amount is seen, don't calculate the fee
but still show the invalid value in the decode.
In analyze psbt, if an invalid amount is seen, set the next step to
be the creator as the creator needs to remake the transaction so that
it is valid.
psbt.cpp definitions except for AnalyzePSBT are used by the wallet and need to
be linked into the wallet binary. AnalyzePSBT is an exception in that it is not
used by the wallet, and depends on node classes like CCoinsViewCache, and on
node global variables like nBytesPerSigOp.
So AnalyzePSBT is more at home in libbitcoin_server than libbitcoin_common, and
in any case needs to be defined in a separate object file than other PSBT
utilities, to avoid dragging link dependencies on node functions and global
variables into the wallet.
Hennadii Stepanov