Merge pull request #16 from ZcashFoundation/jane/precompute

Prior to this PR the zcash script verification logic in zebra has had an issue with quadratic serialization of transactions when verifying scripts. In the script verification API each input is verified individually. This would be fine, except for the fact that we also have to deal with FFI to another language with a different representation for transactions, which requires that we serialize and deserialize each transaction for each call into c++ code.

This PR solves this problem by exporting the newly setup "precomputed transaction" API, which lets us serialize our transaction once, pass it over, have zcash_script deserialize it once, and then pass us a `void*` pointer to the data they'd need for future function calls to verify individual transaction inputs. We then hold onto this pointer and pass it back into the C++ code for each input we verify, which prevents us from needing to do any more serialization for the duration of that transaction verification.

CHANGELOG.md

@@ -8,6 +8,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased] - ReleaseDate
 
+## [0.1.5] - 2020-12-09
+### Changed
+- Updated `depend/zcash` to new version including a precompute API
+
 ## [0.1.4] - 2020-11-17
 ### Changed
 - switched from bindgen `0.55` to bindgen `0.54` to avoid a dependency
@@ -33,7 +37,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Updated `bindgen` to a non yanked version
 
 <!-- next-url -->
-[Unreleased]: https://github.com/ZcashFoundation/zcash_script/compare/v0.1.4...HEAD
+[Unreleased]: https://github.com/ZcashFoundation/zcash_script/compare/v0.1.5...HEAD
+[0.1.5]: https://github.com/ZcashFoundation/zcash_script/compare/v0.1.4...v0.1.5
 [0.1.4]: https://github.com/ZcashFoundation/zcash_script/compare/v0.1.3...v0.1.4
 [0.1.3]: https://github.com/ZcashFoundation/zcash_script/compare/v0.1.2...v0.1.3
 [0.1.2]: https://github.com/ZcashFoundation/zcash_script/compare/v0.1.1...v0.1.2

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "zcash_script"
-version = "0.1.5-alpha.0"
+version = "0.1.6-alpha.0"
 authors = ["Tamas Blummer <tamas.blummer@gmail.com>", "Zcash Foundation <zebra@zfnd.org>"]
 license = "Apache-2.0"
 readme = "README.md"

README.md

@@ -12,3 +12,11 @@
 [docs-url]: https://docs.rs/zcash_script
 
 Rust bindings to the ECC's `zcash_script` c++ library.
+
+### Updating `depend/zcash`
+
+To pull in recent changes from the upstream repo run the following:
+
+```console
+git subtree pull -P depend/zcash <repo> <branch> --squash
+```

depend/zcash/.gitignore

@@ -7,6 +7,7 @@ src/zcash-cli
 src/zcash-gtest
 src/zcash-tx
 src/test/test_bitcoin
+zcutil/bin/
 
 *zcashTest.pk
 *zcashTest.vk
@@ -116,5 +117,6 @@ libzcash_script.pc
 contrib/debian/files
 contrib/debian/substvars
 
+src/fuzzing/*/input
 src/fuzzing/*/output
 src/fuzz.cpp

depend/zcash/COPYING

@@ -29,11 +29,6 @@ source code is not considered a derived work of these Autoconf macros or of the
 dependencies. For further details see 'contrib/debian/copyright'.
 
 
-This product includes software developed by the OpenSSL Project for use in the
-OpenSSL Toolkit (https://www.openssl.org/). This product includes cryptographic
-software written by Eric Young (eay@cryptsoft.com).
-
-
 Although almost all of the Zcash code is licensed under "permissive" open source
 licenses, users and distributors should note that when built using the default
 build options, Zcash depends on Oracle Berkeley DB 6.2.x, which is licensed