* fix parse_coinbase_height()
* move tests and create test for parse_coinbase_height()
* add a coinbase height round trip prop test
* fix range
Co-authored-by: teor <teor@riseup.net>
* extend examples in test
* add more round trip testing
* extend the range of test
Co-authored-by: teor <teor@riseup.net>
* add test for single byte
Co-authored-by: teor <teor@riseup.net>
* Return an error if genesis transparent coinbase data is invalid
This error prevents cryptic errors during genesis coinbase deserialization.
And fix and improve documentation.
* Use the fixed Zcash constant for generated genesis coinbase data
This change is required, because genesis transactions do not have a
coinbase height in their coinbase data.
Zebra already uses `Read::take` to enforce message, body, and block
maximum sizes.
So using `Read::take` on untrusted sizes can result in short reads,
without a corresponding `UnexpectedEof` error. (The old code was
correct, but copying it elsewhere would have been risky.)
The `CoinbaseData` parses the block height separately from the rest of the
free-form coinbase data. However, it had two bugs:
1. It did not require that the height was canonically encoded;
2. Its canonical encoding was incorrect relative to the BIP34-inherited encoding.
This meant that we computed some transaction hashes incorrectly, because when
we re-serialized the coinbase transaction, we would canonically serialize the
coinbase transaction (using the incorrect definition of canonical, bug 2). And
we didn't notice that the wrong definition of canonical encoding was being used
because we accepted what we thought were non-canonically encoded heights.
The relevant rules are here: 877212414a/src/script/script.h (L307-L346)
This commit changes the encoding to reject non-canonically encoded heights, and
to match the correct encoding rules. We check that at least one
non-canonically encoded height is correctly rejected using a new test vector.
The database format increments because we saved a bunch of wrongly encoded blocks.
This discrepancy was originally noticed by @teor2345, who pointed out that a
previous version of the block 202 test vector (now preserved as "bad block
202") did not match the block from zcashd.
* Implement sighash
* move sighash logic to a separate module
* start filling in more of the alg
* start setting up a test case
* make the test useful
* Iter transaction inputs
* better error message for expect
* add support for zip243 sighash
* ohey first testvector is passing, yayyy
* pass the second testvector
* add last testvector
* move a use statement
* use common deserialization code for amount everywhere
* cleanup attributes
* bring in fixed preimage
* fix discrepancy with spec
* always deserialize as a signed value
* Update zebra-chain/src/transaction/sighash.rs
* update unreachable statements
* add serialization impls for nonnegative amounts
* Apply suggestions from code review
* document sighash fn
* tweek docs
* fix mistake in translation for zip243
* consistent error messages
* reorder because i like it more that way
* document more panics
* Update zebra-chain/src/amount.rs
* Add comment regarding the serialization of spend descriptions in sighash
Co-authored-by: teor <teor@riseup.net>
Co-authored-by: Deirdre Connolly <deirdre@zfnd.org>
Marek
Alfredo Garcia
teor
Henry de Valence
Jane Lusby