mirror of
https://github.com/XRPLF/rippled.git
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chore: Reverts formatting changes to external files, adds formatting changes to proto files (#5711)
This change reverts the formatting applied to external files and adds formatting of proto files. As clang-format will complain if a proto file is modified or moved, since the .clang-format file does not explicitly contain a section for proto files, the change has been included in this PR as well.
This commit is contained in:
Bart
@@ -100,3 +100,8 @@ Language: JavaScript
|
||||
---
|
||||
Language: Json
|
||||
IndentWidth: 2
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||||
---
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||||
Language: Proto
|
||||
BasedOnStyle: Google
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||||
ColumnLimit: 0
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||||
IndentWidth: 2
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||||
|
||||
@@ -1,3 +1,3 @@
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||||
---
|
||||
DisableFormat: true
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||||
SortIncludes: false
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||||
SortIncludes: Never
|
||||
1
external/ed25519-donna/README.md
vendored
1
external/ed25519-donna/README.md
vendored
@@ -104,6 +104,7 @@ Use `-DED25519_FORCE_32BIT` to force the use of 32 bit routines even when compil
|
||||
|
||||
clang and icc are also supported
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||||
|
||||
|
||||
#### Usage
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||||
|
||||
To use the code, link against `ed25519.o -mbits` and:
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||||
|
||||
41
external/ed25519-donna/fuzz/README.md
vendored
41
external/ed25519-donna/fuzz/README.md
vendored
@@ -6,35 +6,35 @@ Curve25519 tests that generating a public key from a secret key
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||||
|
||||
# Building
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||||
|
||||
## \*nix + PHP
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## *nix + PHP
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||||
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||||
`php build-nix.php (required parameters) (optional parameters)`
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||||
Required parameters:
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||||
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- `--function=[curve25519,ed25519]`
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||||
- `--bits=[32,64]`
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* `--function=[curve25519,ed25519]`
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* `--bits=[32,64]`
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||||
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Optional parameters:
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- `--with-sse2`
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* `--with-sse2`
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Also fuzz against ed25519-donna-sse2
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- `--with-openssl`
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* `--with-openssl`
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Build with OpenSSL's SHA-512.
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Default: Reference SHA-512 implementation (slow!)
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||||
- `--compiler=[gcc,clang,icc]`
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* `--compiler=[gcc,clang,icc]`
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Default: gcc
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- `--no-asm`
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* `--no-asm`
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Do not use platform specific assembler
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example:
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php build-nix.php --bits=64 --function=ed25519 --with-sse2 --compiler=icc
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@@ -48,11 +48,11 @@ If you are not using OpenSSL, add the `ED25519_REFHASH` define to the projects
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||||
Add the following files to the project:
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- `fuzz/curve25519-ref10.c`
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- `fuzz/ed25519-ref10.c`
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- `fuzz/ed25519-donna.c`
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- `fuzz/ed25519-donna-sse2.c` (optional)
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- `fuzz-[curve25519/ed25519].c` (depending on which you want to fuzz)
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* `fuzz/curve25519-ref10.c`
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* `fuzz/ed25519-ref10.c`
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* `fuzz/ed25519-donna.c`
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* `fuzz/ed25519-donna-sse2.c` (optional)
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* `fuzz-[curve25519/ed25519].c` (depending on which you want to fuzz)
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||||
|
||||
If you are also fuzzing against ed25519-donna-sse2, add the `ED25519_SSE2` define for `fuzz-[curve25519/ed25519].c` under
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its "Properties/Preprocessor/Preprocessor Definitions" option.
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@@ -83,14 +83,14 @@ These are example error dumps (with intentionally introduced errors).
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|
||||
Random data:
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||||
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||||
- sk, or Secret Key
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- m, or Message
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||||
* sk, or Secret Key
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||||
* m, or Message
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||||
|
||||
Generated data:
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|
||||
- pk, or Public Key
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- sig, or Signature
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- valid, or if the signature of the message is valid with the public key
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||||
* pk, or Public Key
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* sig, or Signature
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||||
* valid, or if the signature of the message is valid with the public key
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|
||||
Dump:
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|
||||
@@ -141,11 +141,11 @@ different and does not validate.
|
||||
|
||||
Random data:
|
||||
|
||||
- sk, or Secret Key
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||||
* sk, or Secret Key
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||||
|
||||
Generated data:
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||||
|
||||
- pk, or Public Key
|
||||
* pk, or Public Key
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||||
|
||||
Dump:
|
||||
|
||||
@@ -168,5 +168,6 @@ Dump:
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||||
____,____,____,____,____,____,____,____,____,____,____,____,____,____,____,____,
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||||
____,____,____,____,____,____,____,____,____,____,____,____,____,____,____,____,
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||||
|
||||
|
||||
In this case, curved25519 is totally wrong, while curved25519-sse2 matches the reference
|
||||
implementation.
|
||||
120
external/secp256k1/CHANGELOG.md
vendored
120
external/secp256k1/CHANGELOG.md
vendored
@@ -8,189 +8,153 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
|
||||
## [0.6.0] - 2024-11-04
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||||
|
||||
#### Added
|
||||
|
||||
- New module `musig` implements the MuSig2 multisignature scheme according to the [BIP 327 specification](https://github.com/bitcoin/bips/blob/master/bip-0327.mediawiki). See:
|
||||
- New module `musig` implements the MuSig2 multisignature scheme according to the [BIP 327 specification](https://github.com/bitcoin/bips/blob/master/bip-0327.mediawiki). See:
|
||||
- Header file `include/secp256k1_musig.h` which defines the new API.
|
||||
- Document `doc/musig.md` for further notes on API usage.
|
||||
- Usage example `examples/musig.c`.
|
||||
- New CMake variable `SECP256K1_APPEND_LDFLAGS` for appending linker flags to the build command.
|
||||
- New CMake variable `SECP256K1_APPEND_LDFLAGS` for appending linker flags to the build command.
|
||||
|
||||
#### Changed
|
||||
|
||||
- API functions now use a significantly more robust method to clear secrets from the stack before returning. However, secret clearing remains a best-effort security measure and cannot guarantee complete removal.
|
||||
- Any type `secp256k1_foo` can now be forward-declared using `typedef struct secp256k1_foo secp256k1_foo;` (or also `struct secp256k1_foo;` in C++).
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||||
- Organized CMake build artifacts into dedicated directories (`bin/` for executables, `lib/` for libraries) to improve build output structure and Windows shared library compatibility.
|
||||
- API functions now use a significantly more robust method to clear secrets from the stack before returning. However, secret clearing remains a best-effort security measure and cannot guarantee complete removal.
|
||||
- Any type `secp256k1_foo` can now be forward-declared using `typedef struct secp256k1_foo secp256k1_foo;` (or also `struct secp256k1_foo;` in C++).
|
||||
- Organized CMake build artifacts into dedicated directories (`bin/` for executables, `lib/` for libraries) to improve build output structure and Windows shared library compatibility.
|
||||
|
||||
#### Removed
|
||||
|
||||
- Removed the `secp256k1_scratch_space` struct and its associated functions `secp256k1_scratch_space_create` and `secp256k1_scratch_space_destroy` because the scratch space was unused in the API.
|
||||
- Removed the `secp256k1_scratch_space` struct and its associated functions `secp256k1_scratch_space_create` and `secp256k1_scratch_space_destroy` because the scratch space was unused in the API.
|
||||
|
||||
#### ABI Compatibility
|
||||
|
||||
The symbols `secp256k1_scratch_space_create` and `secp256k1_scratch_space_destroy` were removed.
|
||||
Otherwise, the library maintains backward compatibility with versions 0.3.x through 0.5.x.
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||||
|
||||
## [0.5.1] - 2024-08-01
|
||||
|
||||
#### Added
|
||||
|
||||
- Added usage example for an ElligatorSwift key exchange.
|
||||
- Added usage example for an ElligatorSwift key exchange.
|
||||
|
||||
#### Changed
|
||||
|
||||
- The default size of the precomputed table for signing was changed from 22 KiB to 86 KiB. The size can be changed with the configure option `--ecmult-gen-kb` (`SECP256K1_ECMULT_GEN_KB` for CMake).
|
||||
- "auto" is no longer an accepted value for the `--with-ecmult-window` and `--with-ecmult-gen-kb` configure options (this also applies to `SECP256K1_ECMULT_WINDOW_SIZE` and `SECP256K1_ECMULT_GEN_KB` in CMake). To achieve the same configuration as previously provided by the "auto" value, omit setting the configure option explicitly.
|
||||
- The default size of the precomputed table for signing was changed from 22 KiB to 86 KiB. The size can be changed with the configure option `--ecmult-gen-kb` (`SECP256K1_ECMULT_GEN_KB` for CMake).
|
||||
- "auto" is no longer an accepted value for the `--with-ecmult-window` and `--with-ecmult-gen-kb` configure options (this also applies to `SECP256K1_ECMULT_WINDOW_SIZE` and `SECP256K1_ECMULT_GEN_KB` in CMake). To achieve the same configuration as previously provided by the "auto" value, omit setting the configure option explicitly.
|
||||
|
||||
#### Fixed
|
||||
|
||||
- Fixed compilation when the extrakeys module is disabled.
|
||||
- Fixed compilation when the extrakeys module is disabled.
|
||||
|
||||
#### ABI Compatibility
|
||||
|
||||
The ABI is backward compatible with versions 0.5.0, 0.4.x and 0.3.x.
|
||||
|
||||
## [0.5.0] - 2024-05-06
|
||||
|
||||
#### Added
|
||||
|
||||
- New function `secp256k1_ec_pubkey_sort` that sorts public keys using lexicographic (of compressed serialization) order.
|
||||
- New function `secp256k1_ec_pubkey_sort` that sorts public keys using lexicographic (of compressed serialization) order.
|
||||
|
||||
#### Changed
|
||||
|
||||
- The implementation of the point multiplication algorithm used for signing and public key generation was changed, resulting in improved performance for those operations.
|
||||
- The implementation of the point multiplication algorithm used for signing and public key generation was changed, resulting in improved performance for those operations.
|
||||
- The related configure option `--ecmult-gen-precision` was replaced with `--ecmult-gen-kb` (`SECP256K1_ECMULT_GEN_KB` for CMake).
|
||||
- This changes the supported precomputed table sizes for these operations. The new supported sizes are 2 KiB, 22 KiB, or 86 KiB (while the old supported sizes were 32 KiB, 64 KiB, or 512 KiB).
|
||||
|
||||
#### ABI Compatibility
|
||||
|
||||
The ABI is backward compatible with versions 0.4.x and 0.3.x.
|
||||
|
||||
## [0.4.1] - 2023-12-21
|
||||
|
||||
#### Changed
|
||||
|
||||
- The point multiplication algorithm used for ECDH operations (module `ecdh`) was replaced with a slightly faster one.
|
||||
- Optional handwritten x86_64 assembly for field operations was removed because modern C compilers are able to output more efficient assembly. This change results in a significant speedup of some library functions when handwritten x86_64 assembly is enabled (`--with-asm=x86_64` in GNU Autotools, `-DSECP256K1_ASM=x86_64` in CMake), which is the default on x86_64. Benchmarks with GCC 10.5.0 show a 10% speedup for `secp256k1_ecdsa_verify` and `secp256k1_schnorrsig_verify`.
|
||||
- The point multiplication algorithm used for ECDH operations (module `ecdh`) was replaced with a slightly faster one.
|
||||
- Optional handwritten x86_64 assembly for field operations was removed because modern C compilers are able to output more efficient assembly. This change results in a significant speedup of some library functions when handwritten x86_64 assembly is enabled (`--with-asm=x86_64` in GNU Autotools, `-DSECP256K1_ASM=x86_64` in CMake), which is the default on x86_64. Benchmarks with GCC 10.5.0 show a 10% speedup for `secp256k1_ecdsa_verify` and `secp256k1_schnorrsig_verify`.
|
||||
|
||||
#### ABI Compatibility
|
||||
|
||||
The ABI is backward compatible with versions 0.4.0 and 0.3.x.
|
||||
|
||||
## [0.4.0] - 2023-09-04
|
||||
|
||||
#### Added
|
||||
|
||||
- New module `ellswift` implements ElligatorSwift encoding for public keys and x-only Diffie-Hellman key exchange for them.
|
||||
- New module `ellswift` implements ElligatorSwift encoding for public keys and x-only Diffie-Hellman key exchange for them.
|
||||
ElligatorSwift permits representing secp256k1 public keys as 64-byte arrays which cannot be distinguished from uniformly random. See:
|
||||
- Header file `include/secp256k1_ellswift.h` which defines the new API.
|
||||
- Document `doc/ellswift.md` which explains the mathematical background of the scheme.
|
||||
- The [paper](https://eprint.iacr.org/2022/759) on which the scheme is based.
|
||||
- We now test the library with unreleased development snapshots of GCC and Clang. This gives us an early chance to catch miscompilations and constant-time issues introduced by the compiler (such as those that led to the previous two releases).
|
||||
- We now test the library with unreleased development snapshots of GCC and Clang. This gives us an early chance to catch miscompilations and constant-time issues introduced by the compiler (such as those that led to the previous two releases).
|
||||
|
||||
#### Fixed
|
||||
|
||||
- Fixed symbol visibility in Windows DLL builds, where three internal library symbols were wrongly exported.
|
||||
- Fixed symbol visibility in Windows DLL builds, where three internal library symbols were wrongly exported.
|
||||
|
||||
#### Changed
|
||||
|
||||
- When consuming libsecp256k1 as a static library on Windows, the user must now define the `SECP256K1_STATIC` macro before including `secp256k1.h`.
|
||||
- When consuming libsecp256k1 as a static library on Windows, the user must now define the `SECP256K1_STATIC` macro before including `secp256k1.h`.
|
||||
|
||||
#### ABI Compatibility
|
||||
|
||||
This release is backward compatible with the ABI of 0.3.0, 0.3.1, and 0.3.2. Symbol visibility is now believed to be handled properly on supported platforms and is now considered to be part of the ABI. Please report any improperly exported symbols as a bug.
|
||||
|
||||
## [0.3.2] - 2023-05-13
|
||||
|
||||
We strongly recommend updating to 0.3.2 if you use or plan to use GCC >=13 to compile libsecp256k1. When in doubt, check the GCC version using `gcc -v`.
|
||||
|
||||
#### Security
|
||||
|
||||
- Module `ecdh`: Fix "constant-timeness" issue with GCC 13.1 (and potentially future versions of GCC) that could leave applications using libsecp256k1's ECDH module vulnerable to a timing side-channel attack. The fix avoids secret-dependent control flow during ECDH computations when libsecp256k1 is compiled with GCC 13.1.
|
||||
- Module `ecdh`: Fix "constant-timeness" issue with GCC 13.1 (and potentially future versions of GCC) that could leave applications using libsecp256k1's ECDH module vulnerable to a timing side-channel attack. The fix avoids secret-dependent control flow during ECDH computations when libsecp256k1 is compiled with GCC 13.1.
|
||||
|
||||
#### Fixed
|
||||
|
||||
- Fixed an old bug that permitted compilers to potentially output bad assembly code on x86_64. In theory, it could lead to a crash or a read of unrelated memory, but this has never been observed on any compilers so far.
|
||||
- Fixed an old bug that permitted compilers to potentially output bad assembly code on x86_64. In theory, it could lead to a crash or a read of unrelated memory, but this has never been observed on any compilers so far.
|
||||
|
||||
#### Changed
|
||||
|
||||
- Various improvements and changes to CMake builds. CMake builds remain experimental.
|
||||
- Various improvements and changes to CMake builds. CMake builds remain experimental.
|
||||
- Made API versioning consistent with GNU Autotools builds.
|
||||
- Switched to `BUILD_SHARED_LIBS` variable for controlling whether to build a static or a shared library.
|
||||
- Added `SECP256K1_INSTALL` variable for the controlling whether to install the build artefacts.
|
||||
- Renamed asm build option `arm` to `arm32`. Use `--with-asm=arm32` instead of `--with-asm=arm` (GNU Autotools), and `-DSECP256K1_ASM=arm32` instead of `-DSECP256K1_ASM=arm` (CMake).
|
||||
- Renamed asm build option `arm` to `arm32`. Use `--with-asm=arm32` instead of `--with-asm=arm` (GNU Autotools), and `-DSECP256K1_ASM=arm32` instead of `-DSECP256K1_ASM=arm` (CMake).
|
||||
|
||||
#### ABI Compatibility
|
||||
|
||||
The ABI is compatible with versions 0.3.0 and 0.3.1.
|
||||
|
||||
## [0.3.1] - 2023-04-10
|
||||
|
||||
We strongly recommend updating to 0.3.1 if you use or plan to use Clang >=14 to compile libsecp256k1, e.g., Xcode >=14 on macOS has Clang >=14. When in doubt, check the Clang version using `clang -v`.
|
||||
|
||||
#### Security
|
||||
|
||||
- Fix "constant-timeness" issue with Clang >=14 that could leave applications using libsecp256k1 vulnerable to a timing side-channel attack. The fix avoids secret-dependent control flow and secret-dependent memory accesses in conditional moves of memory objects when libsecp256k1 is compiled with Clang >=14.
|
||||
- Fix "constant-timeness" issue with Clang >=14 that could leave applications using libsecp256k1 vulnerable to a timing side-channel attack. The fix avoids secret-dependent control flow and secret-dependent memory accesses in conditional moves of memory objects when libsecp256k1 is compiled with Clang >=14.
|
||||
|
||||
#### Added
|
||||
|
||||
- Added tests against [Project Wycheproof's](https://github.com/google/wycheproof/) set of ECDSA test vectors (Bitcoin "low-S" variant), a fixed set of test cases designed to trigger various edge cases.
|
||||
- Added tests against [Project Wycheproof's](https://github.com/google/wycheproof/) set of ECDSA test vectors (Bitcoin "low-S" variant), a fixed set of test cases designed to trigger various edge cases.
|
||||
|
||||
#### Changed
|
||||
|
||||
- Increased minimum required CMake version to 3.13. CMake builds remain experimental.
|
||||
- Increased minimum required CMake version to 3.13. CMake builds remain experimental.
|
||||
|
||||
#### ABI Compatibility
|
||||
|
||||
The ABI is compatible with version 0.3.0.
|
||||
|
||||
## [0.3.0] - 2023-03-08
|
||||
|
||||
#### Added
|
||||
|
||||
- Added experimental support for CMake builds. Traditional GNU Autotools builds (`./configure` and `make`) remain fully supported.
|
||||
- Usage examples: Added a recommended method for securely clearing sensitive data, e.g., secret keys, from memory.
|
||||
- Tests: Added a new test binary `noverify_tests`. This binary runs the tests without some additional checks present in the ordinary `tests` binary and is thereby closer to production binaries. The `noverify_tests` binary is automatically run as part of the `make check` target.
|
||||
- Added experimental support for CMake builds. Traditional GNU Autotools builds (`./configure` and `make`) remain fully supported.
|
||||
- Usage examples: Added a recommended method for securely clearing sensitive data, e.g., secret keys, from memory.
|
||||
- Tests: Added a new test binary `noverify_tests`. This binary runs the tests without some additional checks present in the ordinary `tests` binary and is thereby closer to production binaries. The `noverify_tests` binary is automatically run as part of the `make check` target.
|
||||
|
||||
#### Fixed
|
||||
|
||||
- Fixed declarations of API variables for MSVC (`__declspec(dllimport)`). This fixes MSVC builds of programs which link against a libsecp256k1 DLL dynamically and use API variables (and not only API functions). Unfortunately, the MSVC linker now will emit warning `LNK4217` when trying to link against libsecp256k1 statically. Pass `/ignore:4217` to the linker to suppress this warning.
|
||||
- Fixed declarations of API variables for MSVC (`__declspec(dllimport)`). This fixes MSVC builds of programs which link against a libsecp256k1 DLL dynamically and use API variables (and not only API functions). Unfortunately, the MSVC linker now will emit warning `LNK4217` when trying to link against libsecp256k1 statically. Pass `/ignore:4217` to the linker to suppress this warning.
|
||||
|
||||
#### Changed
|
||||
|
||||
- Forbade cloning or destroying `secp256k1_context_static`. Create a new context instead of cloning the static context. (If this change breaks your code, your code is probably wrong.)
|
||||
- Forbade randomizing (copies of) `secp256k1_context_static`. Randomizing a copy of `secp256k1_context_static` did not have any effect and did not provide defense-in-depth protection against side-channel attacks. Create a new context if you want to benefit from randomization.
|
||||
- Forbade cloning or destroying `secp256k1_context_static`. Create a new context instead of cloning the static context. (If this change breaks your code, your code is probably wrong.)
|
||||
- Forbade randomizing (copies of) `secp256k1_context_static`. Randomizing a copy of `secp256k1_context_static` did not have any effect and did not provide defense-in-depth protection against side-channel attacks. Create a new context if you want to benefit from randomization.
|
||||
|
||||
#### Removed
|
||||
|
||||
- Removed the configuration header `src/libsecp256k1-config.h`. We recommend passing flags to `./configure` or `cmake` to set configuration options (see `./configure --help` or `cmake -LH`). If you cannot or do not want to use one of the supported build systems, pass configuration flags such as `-DSECP256K1_ENABLE_MODULE_SCHNORRSIG` manually to the compiler (see the file `configure.ac` for supported flags).
|
||||
- Removed the configuration header `src/libsecp256k1-config.h`. We recommend passing flags to `./configure` or `cmake` to set configuration options (see `./configure --help` or `cmake -LH`). If you cannot or do not want to use one of the supported build systems, pass configuration flags such as `-DSECP256K1_ENABLE_MODULE_SCHNORRSIG` manually to the compiler (see the file `configure.ac` for supported flags).
|
||||
|
||||
#### ABI Compatibility
|
||||
|
||||
Due to changes in the API regarding `secp256k1_context_static` described above, the ABI is _not_ compatible with previous versions.
|
||||
Due to changes in the API regarding `secp256k1_context_static` described above, the ABI is *not* compatible with previous versions.
|
||||
|
||||
## [0.2.0] - 2022-12-12
|
||||
|
||||
#### Added
|
||||
|
||||
- Added usage examples for common use cases in a new `examples/` directory.
|
||||
- Added `secp256k1_selftest`, to be used in conjunction with `secp256k1_context_static`.
|
||||
- Added support for 128-bit wide multiplication on MSVC for x86_64 and arm64, giving roughly a 20% speedup on those platforms.
|
||||
- Added usage examples for common use cases in a new `examples/` directory.
|
||||
- Added `secp256k1_selftest`, to be used in conjunction with `secp256k1_context_static`.
|
||||
- Added support for 128-bit wide multiplication on MSVC for x86_64 and arm64, giving roughly a 20% speedup on those platforms.
|
||||
|
||||
#### Changed
|
||||
|
||||
- Enabled modules `schnorrsig`, `extrakeys` and `ecdh` by default in `./configure`.
|
||||
- The `secp256k1_nonce_function_rfc6979` nonce function, used by default by `secp256k1_ecdsa_sign`, now reduces the message hash modulo the group order to match the specification. This only affects improper use of ECDSA signing API.
|
||||
- Enabled modules `schnorrsig`, `extrakeys` and `ecdh` by default in `./configure`.
|
||||
- The `secp256k1_nonce_function_rfc6979` nonce function, used by default by `secp256k1_ecdsa_sign`, now reduces the message hash modulo the group order to match the specification. This only affects improper use of ECDSA signing API.
|
||||
|
||||
#### Deprecated
|
||||
|
||||
- Deprecated context flags `SECP256K1_CONTEXT_VERIFY` and `SECP256K1_CONTEXT_SIGN`. Use `SECP256K1_CONTEXT_NONE` instead.
|
||||
- Renamed `secp256k1_context_no_precomp` to `secp256k1_context_static`.
|
||||
- Module `schnorrsig`: renamed `secp256k1_schnorrsig_sign` to `secp256k1_schnorrsig_sign32`.
|
||||
- Deprecated context flags `SECP256K1_CONTEXT_VERIFY` and `SECP256K1_CONTEXT_SIGN`. Use `SECP256K1_CONTEXT_NONE` instead.
|
||||
- Renamed `secp256k1_context_no_precomp` to `secp256k1_context_static`.
|
||||
- Module `schnorrsig`: renamed `secp256k1_schnorrsig_sign` to `secp256k1_schnorrsig_sign32`.
|
||||
|
||||
#### ABI Compatibility
|
||||
|
||||
Since this is the first release, we do not compare application binary interfaces.
|
||||
However, there are earlier unreleased versions of libsecp256k1 that are _not_ ABI compatible with this version.
|
||||
However, there are earlier unreleased versions of libsecp256k1 that are *not* ABI compatible with this version.
|
||||
|
||||
## [0.1.0] - 2013-03-05 to 2021-12-25
|
||||
|
||||
|
||||
6
external/secp256k1/CMakePresets.json
vendored
6
external/secp256k1/CMakePresets.json
vendored
@@ -1,9 +1,5 @@
|
||||
{
|
||||
"cmakeMinimumRequired": {
|
||||
"major": 3,
|
||||
"minor": 21,
|
||||
"patch": 0
|
||||
},
|
||||
"cmakeMinimumRequired": {"major": 3, "minor": 21, "patch": 0},
|
||||
"version": 3,
|
||||
"configurePresets": [
|
||||
{
|
||||
|
||||
38
external/secp256k1/CONTRIBUTING.md
vendored
38
external/secp256k1/CONTRIBUTING.md
vendored
@@ -12,14 +12,14 @@ The libsecp256k1 project welcomes contributions in the form of new functionality
|
||||
It is the responsibility of the contributors to convince the maintainers that the proposed functionality is within the project's scope, high-quality and maintainable.
|
||||
Contributors are recommended to provide the following in addition to the new code:
|
||||
|
||||
- **Specification:**
|
||||
* **Specification:**
|
||||
A specification can help significantly in reviewing the new code as it provides documentation and context.
|
||||
It may justify various design decisions, give a motivation and outline security goals.
|
||||
If the specification contains pseudocode, a reference implementation or test vectors, these can be used to compare with the proposed libsecp256k1 code.
|
||||
- **Security Arguments:**
|
||||
* **Security Arguments:**
|
||||
In addition to a defining the security goals, it should be argued that the new functionality meets these goals.
|
||||
Depending on the nature of the new functionality, a wide range of security arguments are acceptable, ranging from being "obviously secure" to rigorous proofs of security.
|
||||
- **Relevance Arguments:**
|
||||
* **Relevance Arguments:**
|
||||
The relevance of the new functionality for the Bitcoin ecosystem should be argued by outlining clear use cases.
|
||||
|
||||
These are not the only factors taken into account when considering to add new functionality.
|
||||
@@ -44,18 +44,18 @@ The Contributor Workflow & Peer Review in libsecp256k1 are similar to Bitcoin Co
|
||||
|
||||
In addition, libsecp256k1 tries to maintain the following coding conventions:
|
||||
|
||||
- No runtime heap allocation (e.g., no `malloc`) unless explicitly requested by the caller (via `secp256k1_context_create` or `secp256k1_scratch_space_create`, for example). Moreover, it should be possible to use the library without any heap allocations.
|
||||
- The tests should cover all lines and branches of the library (see [Test coverage](#coverage)).
|
||||
- Operations involving secret data should be tested for being constant time with respect to the secrets (see [src/ctime_tests.c](src/ctime_tests.c)).
|
||||
- Local variables containing secret data should be cleared explicitly to try to delete secrets from memory.
|
||||
- Use `secp256k1_memcmp_var` instead of `memcmp` (see [#823](https://github.com/bitcoin-core/secp256k1/issues/823)).
|
||||
- As a rule of thumb, the default values for configuration options should target standard desktop machines and align with Bitcoin Core's defaults, and the tests should mostly exercise the default configuration (see [#1549](https://github.com/bitcoin-core/secp256k1/issues/1549#issuecomment-2200559257)).
|
||||
* No runtime heap allocation (e.g., no `malloc`) unless explicitly requested by the caller (via `secp256k1_context_create` or `secp256k1_scratch_space_create`, for example). Moreover, it should be possible to use the library without any heap allocations.
|
||||
* The tests should cover all lines and branches of the library (see [Test coverage](#coverage)).
|
||||
* Operations involving secret data should be tested for being constant time with respect to the secrets (see [src/ctime_tests.c](src/ctime_tests.c)).
|
||||
* Local variables containing secret data should be cleared explicitly to try to delete secrets from memory.
|
||||
* Use `secp256k1_memcmp_var` instead of `memcmp` (see [#823](https://github.com/bitcoin-core/secp256k1/issues/823)).
|
||||
* As a rule of thumb, the default values for configuration options should target standard desktop machines and align with Bitcoin Core's defaults, and the tests should mostly exercise the default configuration (see [#1549](https://github.com/bitcoin-core/secp256k1/issues/1549#issuecomment-2200559257)).
|
||||
|
||||
#### Style conventions
|
||||
|
||||
- Commits should be atomic and diffs should be easy to read. For this reason, do not mix any formatting fixes or code moves with actual code changes. Make sure each individual commit is hygienic: that it builds successfully on its own without warnings, errors, regressions, or test failures.
|
||||
- New code should adhere to the style of existing, in particular surrounding, code. Other than that, we do not enforce strict rules for code formatting.
|
||||
- The code conforms to C89. Most notably, that means that only `/* ... */` comments are allowed (no `//` line comments). Moreover, any declarations in a `{ ... }` block (e.g., a function) must appear at the beginning of the block before any statements. When you would like to declare a variable in the middle of a block, you can open a new block:
|
||||
* Commits should be atomic and diffs should be easy to read. For this reason, do not mix any formatting fixes or code moves with actual code changes. Make sure each individual commit is hygienic: that it builds successfully on its own without warnings, errors, regressions, or test failures.
|
||||
* New code should adhere to the style of existing, in particular surrounding, code. Other than that, we do not enforce strict rules for code formatting.
|
||||
* The code conforms to C89. Most notably, that means that only `/* ... */` comments are allowed (no `//` line comments). Moreover, any declarations in a `{ ... }` block (e.g., a function) must appear at the beginning of the block before any statements. When you would like to declare a variable in the middle of a block, you can open a new block:
|
||||
```C
|
||||
void secp256k_foo(void) {
|
||||
unsigned int x; /* declaration */
|
||||
@@ -68,12 +68,12 @@ In addition, libsecp256k1 tries to maintain the following coding conventions:
|
||||
}
|
||||
}
|
||||
```
|
||||
- Use `unsigned int` instead of just `unsigned`.
|
||||
- Use `void *ptr` instead of `void* ptr`.
|
||||
- Arguments of the publicly-facing API must have a specific order defined in [include/secp256k1.h](include/secp256k1.h).
|
||||
- User-facing comment lines in headers should be limited to 80 chars if possible.
|
||||
- All identifiers in file scope should start with `secp256k1_`.
|
||||
- Avoid trailing whitespace.
|
||||
* Use `unsigned int` instead of just `unsigned`.
|
||||
* Use `void *ptr` instead of `void* ptr`.
|
||||
* Arguments of the publicly-facing API must have a specific order defined in [include/secp256k1.h](include/secp256k1.h).
|
||||
* User-facing comment lines in headers should be limited to 80 chars if possible.
|
||||
* All identifiers in file scope should start with `secp256k1_`.
|
||||
* Avoid trailing whitespace.
|
||||
|
||||
### Tests
|
||||
|
||||
@@ -101,7 +101,7 @@ To create a HTML report with coloured and annotated source code:
|
||||
#### Exhaustive tests
|
||||
|
||||
There are tests of several functions in which a small group replaces secp256k1.
|
||||
These tests are _exhaustive_ since they provide all elements and scalars of the small group as input arguments (see [src/tests_exhaustive.c](src/tests_exhaustive.c)).
|
||||
These tests are *exhaustive* since they provide all elements and scalars of the small group as input arguments (see [src/tests_exhaustive.c](src/tests_exhaustive.c)).
|
||||
|
||||
### Benchmarks
|
||||
|
||||
|
||||
130
external/secp256k1/README.md
vendored
130
external/secp256k1/README.md
vendored
@@ -1,4 +1,5 @@
|
||||
# libsecp256k1
|
||||
libsecp256k1
|
||||
============
|
||||
|
||||
|
||||
[](https://web.libera.chat/#secp256k1)
|
||||
@@ -8,59 +9,60 @@ High-performance high-assurance C library for digital signatures and other crypt
|
||||
This library is intended to be the highest quality publicly available library for cryptography on the secp256k1 curve. However, the primary focus of its development has been for usage in the Bitcoin system and usage unlike Bitcoin's may be less well tested, verified, or suffer from a less well thought out interface. Correct usage requires some care and consideration that the library is fit for your application's purpose.
|
||||
|
||||
Features:
|
||||
* secp256k1 ECDSA signing/verification and key generation.
|
||||
* Additive and multiplicative tweaking of secret/public keys.
|
||||
* Serialization/parsing of secret keys, public keys, signatures.
|
||||
* Constant time, constant memory access signing and public key generation.
|
||||
* Derandomized ECDSA (via RFC6979 or with a caller provided function.)
|
||||
* Very efficient implementation.
|
||||
* Suitable for embedded systems.
|
||||
* No runtime dependencies.
|
||||
* Optional module for public key recovery.
|
||||
* Optional module for ECDH key exchange.
|
||||
* Optional module for Schnorr signatures according to [BIP-340](https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki).
|
||||
* Optional module for ElligatorSwift key exchange according to [BIP-324](https://github.com/bitcoin/bips/blob/master/bip-0324.mediawiki).
|
||||
* Optional module for MuSig2 Schnorr multi-signatures according to [BIP-327](https://github.com/bitcoin/bips/blob/master/bip-0327.mediawiki).
|
||||
|
||||
- secp256k1 ECDSA signing/verification and key generation.
|
||||
- Additive and multiplicative tweaking of secret/public keys.
|
||||
- Serialization/parsing of secret keys, public keys, signatures.
|
||||
- Constant time, constant memory access signing and public key generation.
|
||||
- Derandomized ECDSA (via RFC6979 or with a caller provided function.)
|
||||
- Very efficient implementation.
|
||||
- Suitable for embedded systems.
|
||||
- No runtime dependencies.
|
||||
- Optional module for public key recovery.
|
||||
- Optional module for ECDH key exchange.
|
||||
- Optional module for Schnorr signatures according to [BIP-340](https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki).
|
||||
- Optional module for ElligatorSwift key exchange according to [BIP-324](https://github.com/bitcoin/bips/blob/master/bip-0324.mediawiki).
|
||||
- Optional module for MuSig2 Schnorr multi-signatures according to [BIP-327](https://github.com/bitcoin/bips/blob/master/bip-0327.mediawiki).
|
||||
Implementation details
|
||||
----------------------
|
||||
|
||||
## Implementation details
|
||||
* General
|
||||
* No runtime heap allocation.
|
||||
* Extensive testing infrastructure.
|
||||
* Structured to facilitate review and analysis.
|
||||
* Intended to be portable to any system with a C89 compiler and uint64_t support.
|
||||
* No use of floating types.
|
||||
* Expose only higher level interfaces to minimize the API surface and improve application security. ("Be difficult to use insecurely.")
|
||||
* Field operations
|
||||
* Optimized implementation of arithmetic modulo the curve's field size (2^256 - 0x1000003D1).
|
||||
* Using 5 52-bit limbs
|
||||
* Using 10 26-bit limbs (including hand-optimized assembly for 32-bit ARM, by Wladimir J. van der Laan).
|
||||
* This is an experimental feature that has not received enough scrutiny to satisfy the standard of quality of this library but is made available for testing and review by the community.
|
||||
* Scalar operations
|
||||
* Optimized implementation without data-dependent branches of arithmetic modulo the curve's order.
|
||||
* Using 4 64-bit limbs (relying on __int128 support in the compiler).
|
||||
* Using 8 32-bit limbs.
|
||||
* Modular inverses (both field elements and scalars) based on [safegcd](https://gcd.cr.yp.to/index.html) with some modifications, and a variable-time variant (by Peter Dettman).
|
||||
* Group operations
|
||||
* Point addition formula specifically simplified for the curve equation (y^2 = x^3 + 7).
|
||||
* Use addition between points in Jacobian and affine coordinates where possible.
|
||||
* Use a unified addition/doubling formula where necessary to avoid data-dependent branches.
|
||||
* Point/x comparison without a field inversion by comparison in the Jacobian coordinate space.
|
||||
* Point multiplication for verification (a*P + b*G).
|
||||
* Use wNAF notation for point multiplicands.
|
||||
* Use a much larger window for multiples of G, using precomputed multiples.
|
||||
* Use Shamir's trick to do the multiplication with the public key and the generator simultaneously.
|
||||
* Use secp256k1's efficiently-computable endomorphism to split the P multiplicand into 2 half-sized ones.
|
||||
* Point multiplication for signing
|
||||
* Use a precomputed table of multiples of powers of 16 multiplied with the generator, so general multiplication becomes a series of additions.
|
||||
* Intended to be completely free of timing sidechannels for secret-key operations (on reasonable hardware/toolchains)
|
||||
* Access the table with branch-free conditional moves so memory access is uniform.
|
||||
* No data-dependent branches
|
||||
* Optional runtime blinding which attempts to frustrate differential power analysis.
|
||||
* The precomputed tables add and eventually subtract points for which no known scalar (secret key) is known, preventing even an attacker with control over the secret key used to control the data internally.
|
||||
|
||||
- General
|
||||
- No runtime heap allocation.
|
||||
- Extensive testing infrastructure.
|
||||
- Structured to facilitate review and analysis.
|
||||
- Intended to be portable to any system with a C89 compiler and uint64_t support.
|
||||
- No use of floating types.
|
||||
- Expose only higher level interfaces to minimize the API surface and improve application security. ("Be difficult to use insecurely.")
|
||||
- Field operations
|
||||
- Optimized implementation of arithmetic modulo the curve's field size (2^256 - 0x1000003D1).
|
||||
- Using 5 52-bit limbs
|
||||
- Using 10 26-bit limbs (including hand-optimized assembly for 32-bit ARM, by Wladimir J. van der Laan).
|
||||
- This is an experimental feature that has not received enough scrutiny to satisfy the standard of quality of this library but is made available for testing and review by the community.
|
||||
- Scalar operations
|
||||
- Optimized implementation without data-dependent branches of arithmetic modulo the curve's order.
|
||||
- Using 4 64-bit limbs (relying on \_\_int128 support in the compiler).
|
||||
- Using 8 32-bit limbs.
|
||||
- Modular inverses (both field elements and scalars) based on [safegcd](https://gcd.cr.yp.to/index.html) with some modifications, and a variable-time variant (by Peter Dettman).
|
||||
- Group operations
|
||||
- Point addition formula specifically simplified for the curve equation (y^2 = x^3 + 7).
|
||||
- Use addition between points in Jacobian and affine coordinates where possible.
|
||||
- Use a unified addition/doubling formula where necessary to avoid data-dependent branches.
|
||||
- Point/x comparison without a field inversion by comparison in the Jacobian coordinate space.
|
||||
- Point multiplication for verification (a*P + b*G).
|
||||
- Use wNAF notation for point multiplicands.
|
||||
- Use a much larger window for multiples of G, using precomputed multiples.
|
||||
- Use Shamir's trick to do the multiplication with the public key and the generator simultaneously.
|
||||
- Use secp256k1's efficiently-computable endomorphism to split the P multiplicand into 2 half-sized ones.
|
||||
- Point multiplication for signing
|
||||
- Use a precomputed table of multiples of powers of 16 multiplied with the generator, so general multiplication becomes a series of additions.
|
||||
- Intended to be completely free of timing sidechannels for secret-key operations (on reasonable hardware/toolchains)
|
||||
- Access the table with branch-free conditional moves so memory access is uniform.
|
||||
- No data-dependent branches
|
||||
- Optional runtime blinding which attempts to frustrate differential power analysis.
|
||||
- The precomputed tables add and eventually subtract points for which no known scalar (secret key) is known, preventing even an attacker with control over the secret key used to control the data internally.
|
||||
|
||||
## Building with Autotools
|
||||
Building with Autotools
|
||||
-----------------------
|
||||
|
||||
$ ./autogen.sh
|
||||
$ ./configure
|
||||
@@ -70,7 +72,8 @@ Features:
|
||||
|
||||
To compile optional modules (such as Schnorr signatures), you need to run `./configure` with additional flags (such as `--enable-module-schnorrsig`). Run `./configure --help` to see the full list of available flags.
|
||||
|
||||
## Building with CMake (experimental)
|
||||
Building with CMake (experimental)
|
||||
----------------------------------
|
||||
|
||||
To maintain a pristine source tree, CMake encourages to perform an out-of-source build by using a separate dedicated build tree.
|
||||
|
||||
@@ -106,19 +109,18 @@ In "Developer Command Prompt for VS 2022":
|
||||
>cmake -G "Visual Studio 17 2022" -A x64 -S . -B build
|
||||
>cmake --build build --config RelWithDebInfo
|
||||
|
||||
## Usage examples
|
||||
|
||||
Usage examples
|
||||
-----------
|
||||
Usage examples can be found in the [examples](examples) directory. To compile them you need to configure with `--enable-examples`.
|
||||
|
||||
- [ECDSA example](examples/ecdsa.c)
|
||||
- [Schnorr signatures example](examples/schnorr.c)
|
||||
- [Deriving a shared secret (ECDH) example](examples/ecdh.c)
|
||||
- [ElligatorSwift key exchange example](examples/ellswift.c)
|
||||
* [ECDSA example](examples/ecdsa.c)
|
||||
* [Schnorr signatures example](examples/schnorr.c)
|
||||
* [Deriving a shared secret (ECDH) example](examples/ecdh.c)
|
||||
* [ElligatorSwift key exchange example](examples/ellswift.c)
|
||||
|
||||
To compile the Schnorr signature and ECDH examples, you also need to configure with `--enable-module-schnorrsig` and `--enable-module-ecdh`.
|
||||
|
||||
## Benchmark
|
||||
|
||||
Benchmark
|
||||
------------
|
||||
If configured with `--enable-benchmark` (which is the default), binaries for benchmarking the libsecp256k1 functions will be present in the root directory after the build.
|
||||
|
||||
To print the benchmark result to the command line:
|
||||
@@ -129,10 +131,12 @@ To create a CSV file for the benchmark result :
|
||||
|
||||
$ ./bench_name | sed '2d;s/ \{1,\}//g' > bench_name.csv
|
||||
|
||||
## Reporting a vulnerability
|
||||
Reporting a vulnerability
|
||||
------------
|
||||
|
||||
See [SECURITY.md](SECURITY.md)
|
||||
|
||||
## Contributing to libsecp256k1
|
||||
Contributing to libsecp256k1
|
||||
------------
|
||||
|
||||
See [CONTRIBUTING.md](CONTRIBUTING.md)
|
||||
|
||||
2
external/secp256k1/SECURITY.md
vendored
2
external/secp256k1/SECURITY.md
vendored
@@ -7,7 +7,7 @@ To report security issues send an email to secp256k1-security@bitcoincore.org (n
|
||||
The following keys may be used to communicate sensitive information to developers:
|
||||
|
||||
| Name | Fingerprint |
|
||||
| ------------- | ------------------------------------------------- |
|
||||
|------|-------------|
|
||||
| Pieter Wuille | 133E AC17 9436 F14A 5CF1 B794 860F EB80 4E66 9320 |
|
||||
| Jonas Nick | 36C7 1A37 C9D9 88BD E825 08D9 B1A7 0E4F 8DCD 0366 |
|
||||
| Tim Ruffing | 09E0 3F87 1092 E40E 106E 902B 33BC 86AB 80FF 5516 |
|
||||
|
||||
410
external/secp256k1/doc/ellswift.md
vendored
410
external/secp256k1/doc/ellswift.md
vendored
@@ -5,17 +5,17 @@ construction in the
|
||||
["SwiftEC: Shallue–van de Woestijne Indifferentiable Function To Elliptic Curves"](https://eprint.iacr.org/2022/759)
|
||||
paper by Jorge Chávez-Saab, Francisco Rodríguez-Henríquez, and Mehdi Tibouchi.
|
||||
|
||||
- [1. Introduction](#1-introduction)
|
||||
- [2. The decoding function](#2-the-decoding-function)
|
||||
- [2.1 Decoding for `secp256k1`](#21-decoding-for-secp256k1)
|
||||
- [3. The encoding function](#3-the-encoding-function)
|
||||
- [3.1 Switching to _v, w_ coordinates](#31-switching-to-v-w-coordinates)
|
||||
- [3.2 Avoiding computing all inverses](#32-avoiding-computing-all-inverses)
|
||||
- [3.3 Finding the inverse](#33-finding-the-inverse)
|
||||
- [3.4 Dealing with special cases](#34-dealing-with-special-cases)
|
||||
- [3.5 Encoding for `secp256k1`](#35-encoding-for-secp256k1)
|
||||
- [4. Encoding and decoding full _(x, y)_ coordinates](#4-encoding-and-decoding-full-x-y-coordinates)
|
||||
- [4.1 Full _(x, y)_ coordinates for `secp256k1`](#41-full-x-y-coordinates-for-secp256k1)
|
||||
* [1. Introduction](#1-introduction)
|
||||
* [2. The decoding function](#2-the-decoding-function)
|
||||
+ [2.1 Decoding for `secp256k1`](#21-decoding-for-secp256k1)
|
||||
* [3. The encoding function](#3-the-encoding-function)
|
||||
+ [3.1 Switching to *v, w* coordinates](#31-switching-to-v-w-coordinates)
|
||||
+ [3.2 Avoiding computing all inverses](#32-avoiding-computing-all-inverses)
|
||||
+ [3.3 Finding the inverse](#33-finding-the-inverse)
|
||||
+ [3.4 Dealing with special cases](#34-dealing-with-special-cases)
|
||||
+ [3.5 Encoding for `secp256k1`](#35-encoding-for-secp256k1)
|
||||
* [4. Encoding and decoding full *(x, y)* coordinates](#4-encoding-and-decoding-full-x-y-coordinates)
|
||||
+ [4.1 Full *(x, y)* coordinates for `secp256k1`](#41-full-x-y-coordinates-for-secp256k1)
|
||||
|
||||
## 1. Introduction
|
||||
|
||||
@@ -34,14 +34,13 @@ are taken modulo $p$), and then evaluating $F_u(t)$, which for every $u$ and $t$
|
||||
x-coordinate on the curve. The functions $F_u$ will be defined in [Section 2](#2-the-decoding-function).
|
||||
|
||||
**Encoding** a given $x$ coordinate is conceptually done as follows:
|
||||
* Loop:
|
||||
* Pick a uniformly random field element $u.$
|
||||
* Compute the set $L = F_u^{-1}(x)$ of $t$ values for which $F_u(t) = x$, which may have up to *8* elements.
|
||||
* With probability $1 - \dfrac{\\#L}{8}$, restart the loop.
|
||||
* Select a uniformly random $t \in L$ and return $(u, t).$
|
||||
|
||||
- Loop:
|
||||
- Pick a uniformly random field element $u.$
|
||||
- Compute the set $L = F_u^{-1}(x)$ of $t$ values for which $F_u(t) = x$, which may have up to _8_ elements.
|
||||
- With probability $1 - \dfrac{\\#L}{8}$, restart the loop.
|
||||
- Select a uniformly random $t \in L$ and return $(u, t).$
|
||||
|
||||
This is the _ElligatorSwift_ algorithm, here given for just x-coordinates. An extension to full
|
||||
This is the *ElligatorSwift* algorithm, here given for just x-coordinates. An extension to full
|
||||
$(x, y)$ points will be given in [Section 4](#4-encoding-and-decoding-full-x-y-coordinates).
|
||||
The algorithm finds a uniformly random $(u, t)$ among (almost all) those
|
||||
for which $F_u(t) = x.$ Section 3.2 in the paper proves that the number of such encodings for
|
||||
@@ -51,40 +50,37 @@ almost all x-coordinates on the curve (all but at most 39) is close to two times
|
||||
## 2. The decoding function
|
||||
|
||||
First some definitions:
|
||||
|
||||
- $\mathbb{F}$ is the finite field of size $q$, of characteristic 5 or more, and $q \equiv 1 \mod 3.$
|
||||
- For `secp256k1`, $q = 2^{256} - 2^{32} - 977$, which satisfies that requirement.
|
||||
- Let $E$ be the elliptic curve of points $(x, y) \in \mathbb{F}^2$ for which $y^2 = x^3 + ax + b$, with $a$ and $b$
|
||||
* $\mathbb{F}$ is the finite field of size $q$, of characteristic 5 or more, and $q \equiv 1 \mod 3.$
|
||||
* For `secp256k1`, $q = 2^{256} - 2^{32} - 977$, which satisfies that requirement.
|
||||
* Let $E$ be the elliptic curve of points $(x, y) \in \mathbb{F}^2$ for which $y^2 = x^3 + ax + b$, with $a$ and $b$
|
||||
public constants, for which $\Delta_E = -16(4a^3 + 27b^2)$ is a square, and at least one of $(-b \pm \sqrt{-3 \Delta_E} / 36)/2$ is a square.
|
||||
This implies that the order of $E$ is either odd, or a multiple of _4_.
|
||||
This implies that the order of $E$ is either odd, or a multiple of *4*.
|
||||
If $a=0$, this condition is always fulfilled.
|
||||
- For `secp256k1`, $a=0$ and $b=7.$
|
||||
- Let the function $g(x) = x^3 + ax + b$, so the $E$ curve equation is also $y^2 = g(x).$
|
||||
- Let the function $h(x) = 3x^3 + 4a.$
|
||||
- Define $V$ as the set of solutions $(x_1, x_2, x_3, z)$ to $z^2 = g(x_1)g(x_2)g(x_3).$
|
||||
- Define $S_u$ as the set of solutions $(X, Y)$ to $X^2 + h(u)Y^2 = -g(u)$ and $Y \neq 0.$
|
||||
- $P_u$ is a function from $\mathbb{F}$ to $S_u$ that will be defined below.
|
||||
- $\psi_u$ is a function from $S_u$ to $V$ that will be defined below.
|
||||
* For `secp256k1`, $a=0$ and $b=7.$
|
||||
* Let the function $g(x) = x^3 + ax + b$, so the $E$ curve equation is also $y^2 = g(x).$
|
||||
* Let the function $h(x) = 3x^3 + 4a.$
|
||||
* Define $V$ as the set of solutions $(x_1, x_2, x_3, z)$ to $z^2 = g(x_1)g(x_2)g(x_3).$
|
||||
* Define $S_u$ as the set of solutions $(X, Y)$ to $X^2 + h(u)Y^2 = -g(u)$ and $Y \neq 0.$
|
||||
* $P_u$ is a function from $\mathbb{F}$ to $S_u$ that will be defined below.
|
||||
* $\psi_u$ is a function from $S_u$ to $V$ that will be defined below.
|
||||
|
||||
**Note**: In the paper:
|
||||
|
||||
- $F_u$ corresponds to $F_{0,u}$ there.
|
||||
- $P_u(t)$ is called $P$ there.
|
||||
- All $S_u$ sets together correspond to $S$ there.
|
||||
- All $\psi_u$ functions together (operating on elements of $S$) correspond to $\psi$ there.
|
||||
* $F_u$ corresponds to $F_{0,u}$ there.
|
||||
* $P_u(t)$ is called $P$ there.
|
||||
* All $S_u$ sets together correspond to $S$ there.
|
||||
* All $\psi_u$ functions together (operating on elements of $S$) correspond to $\psi$ there.
|
||||
|
||||
Note that for $V$, the left hand side of the equation $z^2$ is square, and thus the right
|
||||
hand must also be square. As multiplying non-squares results in a square in $\mathbb{F}$,
|
||||
out of the three right-hand side factors an even number must be non-squares.
|
||||
This implies that exactly _1_ or exactly _3_ out of
|
||||
This implies that exactly *1* or exactly *3* out of
|
||||
$\\{g(x_1), g(x_2), g(x_3)\\}$ must be square, and thus that for any $(x_1,x_2,x_3,z) \in V$,
|
||||
at least one of $\\{x_1, x_2, x_3\\}$ must be a valid x-coordinate on $E.$ There is one exception
|
||||
to this, namely when $z=0$, but even then one of the three values is a valid x-coordinate.
|
||||
|
||||
**Define** the decoding function $F_u(t)$ as:
|
||||
|
||||
- Let $(x_1, x_2, x_3, z) = \psi_u(P_u(t)).$
|
||||
- Return the first element $x$ of $(x_3, x_2, x_1)$ which is a valid x-coordinate on $E$ (i.e., $g(x)$ is square).
|
||||
* Let $(x_1, x_2, x_3, z) = \psi_u(P_u(t)).$
|
||||
* Return the first element $x$ of $(x_3, x_2, x_1)$ which is a valid x-coordinate on $E$ (i.e., $g(x)$ is square).
|
||||
|
||||
$P_u(t) = (X(u, t), Y(u, t))$, where:
|
||||
|
||||
@@ -102,13 +98,12 @@ Y(u, t) & = & \left\\{\begin{array}{ll}
|
||||
$$
|
||||
|
||||
$P_u(t)$ is defined:
|
||||
|
||||
- For $a=0$, unless:
|
||||
- $u = 0$ or $t = 0$ (division by zero)
|
||||
- $g(u) = -t^2$ (would give $Y=0$).
|
||||
- For $a \neq 0$, unless:
|
||||
- $X_0(u) = 0$ or $h(u)t^2 = -1$ (division by zero)
|
||||
- $Y_0(u) (1 - h(u)t^2) = 2X_0(u)t$ (would give $Y=0$).
|
||||
* For $a=0$, unless:
|
||||
* $u = 0$ or $t = 0$ (division by zero)
|
||||
* $g(u) = -t^2$ (would give $Y=0$).
|
||||
* For $a \neq 0$, unless:
|
||||
* $X_0(u) = 0$ or $h(u)t^2 = -1$ (division by zero)
|
||||
* $Y_0(u) (1 - h(u)t^2) = 2X_0(u)t$ (would give $Y=0$).
|
||||
|
||||
The functions $X_0(u)$ and $Y_0(u)$ are defined in Appendix A of the paper, and depend on various properties of $E.$
|
||||
|
||||
@@ -128,22 +123,20 @@ $$
|
||||
Put together and specialized for $a=0$ curves, decoding $(u, t)$ to an x-coordinate is:
|
||||
|
||||
**Define** $F_u(t)$ as:
|
||||
|
||||
- Let $X = \dfrac{u^3 + b - t^2}{2t}.$
|
||||
- Let $Y = \dfrac{X + t}{u\sqrt{-3}}.$
|
||||
- Return the first $x$ in $(u + 4Y^2, \dfrac{-X}{2Y} - \dfrac{u}{2}, \dfrac{X}{2Y} - \dfrac{u}{2})$ for which $g(x)$ is square.
|
||||
* Let $X = \dfrac{u^3 + b - t^2}{2t}.$
|
||||
* Let $Y = \dfrac{X + t}{u\sqrt{-3}}.$
|
||||
* Return the first $x$ in $(u + 4Y^2, \dfrac{-X}{2Y} - \dfrac{u}{2}, \dfrac{X}{2Y} - \dfrac{u}{2})$ for which $g(x)$ is square.
|
||||
|
||||
To make sure that every input decodes to a valid x-coordinate, we remap the inputs in case
|
||||
$P_u$ is not defined (when $u=0$, $t=0$, or $g(u) = -t^2$):
|
||||
|
||||
**Define** $F_u(t)$ as:
|
||||
|
||||
- Let $u'=u$ if $u \neq 0$; $1$ otherwise (guaranteeing $u' \neq 0$).
|
||||
- Let $t'=t$ if $t \neq 0$; $1$ otherwise (guaranteeing $t' \neq 0$).
|
||||
- Let $t''=t'$ if $g(u') \neq -t'^2$; $2t'$ otherwise (guaranteeing $t'' \neq 0$ and $g(u') \neq -t''^2$).
|
||||
- Let $X = \dfrac{u'^3 + b - t''^2}{2t''}.$
|
||||
- Let $Y = \dfrac{X + t''}{u'\sqrt{-3}}.$
|
||||
- Return the first $x$ in $(u' + 4Y^2, \dfrac{-X}{2Y} - \dfrac{u'}{2}, \dfrac{X}{2Y} - \dfrac{u'}{2})$ for which $x^3 + b$ is square.
|
||||
* Let $u'=u$ if $u \neq 0$; $1$ otherwise (guaranteeing $u' \neq 0$).
|
||||
* Let $t'=t$ if $t \neq 0$; $1$ otherwise (guaranteeing $t' \neq 0$).
|
||||
* Let $t''=t'$ if $g(u') \neq -t'^2$; $2t'$ otherwise (guaranteeing $t'' \neq 0$ and $g(u') \neq -t''^2$).
|
||||
* Let $X = \dfrac{u'^3 + b - t''^2}{2t''}.$
|
||||
* Let $Y = \dfrac{X + t''}{u'\sqrt{-3}}.$
|
||||
* Return the first $x$ in $(u' + 4Y^2, \dfrac{-X}{2Y} - \dfrac{u'}{2}, \dfrac{X}{2Y} - \dfrac{u'}{2})$ for which $x^3 + b$ is square.
|
||||
|
||||
The choices here are not strictly necessary. Just returning a fixed constant in any of the undefined cases would suffice,
|
||||
but the approach here is simple enough and gives fairly uniform output even in these cases.
|
||||
@@ -157,11 +150,10 @@ in `secp256k1_ellswift_xswiftec_var` (which outputs the actual x-coordinate).
|
||||
## 3. The encoding function
|
||||
|
||||
To implement $F_u^{-1}(x)$, the function to find the set of inverses $t$ for which $F_u(t) = x$, we have to reverse the process:
|
||||
|
||||
- Find all the $(X, Y) \in S_u$ that could have given rise to $x$, through the $x_1$, $x_2$, or $x_3$ formulas in $\psi_u.$
|
||||
- Map those $(X, Y)$ solutions to $t$ values using $P_u^{-1}(X, Y).$
|
||||
- For each of the found $t$ values, verify that $F_u(t) = x.$
|
||||
- Return the remaining $t$ values.
|
||||
* Find all the $(X, Y) \in S_u$ that could have given rise to $x$, through the $x_1$, $x_2$, or $x_3$ formulas in $\psi_u.$
|
||||
* Map those $(X, Y)$ solutions to $t$ values using $P_u^{-1}(X, Y).$
|
||||
* For each of the found $t$ values, verify that $F_u(t) = x.$
|
||||
* Return the remaining $t$ values.
|
||||
|
||||
The function $P_u^{-1}$, which finds $t$ given $(X, Y) \in S_u$, is significantly simpler than $P_u:$
|
||||
|
||||
@@ -193,14 +185,13 @@ precedence over both. Because of this, the $g(-u-x)$ being square test for $x_1$
|
||||
values round-trip back to the input $x$ correctly. This is the reason for choosing the $(x_3, x_2, x_1)$ precedence order in the decoder;
|
||||
any order which does not place $x_3$ first requires more complicated round-trip checks in the encoder.
|
||||
|
||||
### 3.1 Switching to _v, w_ coordinates
|
||||
### 3.1 Switching to *v, w* coordinates
|
||||
|
||||
Before working out the formulas for all this, we switch to different variables for $S_u.$ Let $v = (X/Y - u)/2$, and
|
||||
$w = 2Y.$ Or in the other direction, $X = w(u/2 + v)$ and $Y = w/2:$
|
||||
|
||||
- $S_u'$ becomes the set of $(v, w)$ for which $w^2 (u^2 + uv + v^2 + a) = -g(u)$ and $w \neq 0.$
|
||||
- For $a=0$ curves, $P_u^{-1}$ can be stated for $(v,w)$ as $P_u^{'-1}(v, w) = w\left(\frac{\sqrt{-3}-1}{2}u - v\right).$
|
||||
- $\psi_u$ can be stated for $(v, w)$ as $\psi_u'(v, w) = (x_1, x_2, x_3, z)$, where
|
||||
* $S_u'$ becomes the set of $(v, w)$ for which $w^2 (u^2 + uv + v^2 + a) = -g(u)$ and $w \neq 0.$
|
||||
* For $a=0$ curves, $P_u^{-1}$ can be stated for $(v,w)$ as $P_u^{'-1}(v, w) = w\left(\frac{\sqrt{-3}-1}{2}u - v\right).$
|
||||
* $\psi_u$ can be stated for $(v, w)$ as $\psi_u'(v, w) = (x_1, x_2, x_3, z)$, where
|
||||
|
||||
$$
|
||||
\begin{array}{lcl}
|
||||
@@ -213,37 +204,34 @@ $$
|
||||
|
||||
We can now write the expressions for finding $(v, w)$ given $x$ explicitly, by solving each of the $\\{x_1, x_2, x_3\\}$
|
||||
expressions for $v$ or $w$, and using the $S_u'$ equation to find the other variable:
|
||||
|
||||
- Assuming $x = x_1$, we find $v = x$ and $w = \pm\sqrt{-g(u)/(u^2 + uv + v^2 + a)}$ (two solutions).
|
||||
- Assuming $x = x_2$, we find $v = -u-x$ and $w = \pm\sqrt{-g(u)/(u^2 + uv + v^2 + a)}$ (two solutions).
|
||||
- Assuming $x = x_3$, we find $w = \pm\sqrt{x-u}$ and $v = -u/2 \pm \sqrt{-w^2(4g(u) + w^2h(u))}/(2w^2)$ (four solutions).
|
||||
* Assuming $x = x_1$, we find $v = x$ and $w = \pm\sqrt{-g(u)/(u^2 + uv + v^2 + a)}$ (two solutions).
|
||||
* Assuming $x = x_2$, we find $v = -u-x$ and $w = \pm\sqrt{-g(u)/(u^2 + uv + v^2 + a)}$ (two solutions).
|
||||
* Assuming $x = x_3$, we find $w = \pm\sqrt{x-u}$ and $v = -u/2 \pm \sqrt{-w^2(4g(u) + w^2h(u))}/(2w^2)$ (four solutions).
|
||||
|
||||
### 3.2 Avoiding computing all inverses
|
||||
|
||||
The _ElligatorSwift_ algorithm as stated in Section 1 requires the computation of $L = F_u^{-1}(x)$ (the
|
||||
The *ElligatorSwift* algorithm as stated in Section 1 requires the computation of $L = F_u^{-1}(x)$ (the
|
||||
set of all $t$ such that $(u, t)$ decode to $x$) in full. This is unnecessary.
|
||||
|
||||
Observe that the procedure of restarting with probability $(1 - \frac{\\#L}{8})$ and otherwise returning a
|
||||
uniformly random element from $L$ is actually equivalent to always padding $L$ with $\bot$ values up to length 8,
|
||||
picking a uniformly random element from that, restarting whenever $\bot$ is picked:
|
||||
|
||||
**Define** _ElligatorSwift(x)_ as:
|
||||
|
||||
- Loop:
|
||||
- Pick a uniformly random field element $u.$
|
||||
- Compute the set $L = F_u^{-1}(x).$
|
||||
- Let $T$ be the 8-element vector consisting of the elements of $L$, plus $8 - \\#L$ times $\\{\bot\\}.$
|
||||
- Select a uniformly random $t \in T.$
|
||||
- If $t \neq \bot$, return $(u, t)$; restart loop otherwise.
|
||||
**Define** *ElligatorSwift(x)* as:
|
||||
* Loop:
|
||||
* Pick a uniformly random field element $u.$
|
||||
* Compute the set $L = F_u^{-1}(x).$
|
||||
* Let $T$ be the 8-element vector consisting of the elements of $L$, plus $8 - \\#L$ times $\\{\bot\\}.$
|
||||
* Select a uniformly random $t \in T.$
|
||||
* If $t \neq \bot$, return $(u, t)$; restart loop otherwise.
|
||||
|
||||
Now notice that the order of elements in $T$ does not matter, as all we do is pick a uniformly
|
||||
random element in it, so we do not need to have all $\bot$ values at the end.
|
||||
As we have 8 distinct formulas for finding $(v, w)$ (taking the variants due to $\pm$ into account),
|
||||
we can associate every index in $T$ with exactly one of those formulas, making sure that:
|
||||
|
||||
- Formulas that yield no solutions (due to division by zero or non-existing square roots) or invalid solutions are made to return $\bot.$
|
||||
- For the $x_1$ and $x_2$ cases, if $g(-u-x)$ is a square, $\bot$ is returned instead (the round-trip check).
|
||||
- In case multiple formulas would return the same non- $\bot$ result, all but one of those must be turned into $\bot$ to avoid biasing those.
|
||||
* Formulas that yield no solutions (due to division by zero or non-existing square roots) or invalid solutions are made to return $\bot.$
|
||||
* For the $x_1$ and $x_2$ cases, if $g(-u-x)$ is a square, $\bot$ is returned instead (the round-trip check).
|
||||
* In case multiple formulas would return the same non- $\bot$ result, all but one of those must be turned into $\bot$ to avoid biasing those.
|
||||
|
||||
The last condition above only occurs with negligible probability for cryptographically-sized curves, but is interesting
|
||||
to take into account as it allows exhaustive testing in small groups. See [Section 3.4](#34-dealing-with-special-cases)
|
||||
@@ -252,13 +240,12 @@ for an analysis of all the negligible cases.
|
||||
If we define $T = (G_{0,u}(x), G_{1,u}(x), \ldots, G_{7,u}(x))$, with each $G_{i,u}$ matching one of the formulas,
|
||||
the loop can be simplified to only compute one of the inverses instead of all of them:
|
||||
|
||||
**Define** _ElligatorSwift(x)_ as:
|
||||
|
||||
- Loop:
|
||||
- Pick a uniformly random field element $u.$
|
||||
- Pick a uniformly random integer $c$ in $[0,8).$
|
||||
- Let $t = G_{c,u}(x).$
|
||||
- If $t \neq \bot$, return $(u, t)$; restart loop otherwise.
|
||||
**Define** *ElligatorSwift(x)* as:
|
||||
* Loop:
|
||||
* Pick a uniformly random field element $u.$
|
||||
* Pick a uniformly random integer $c$ in $[0,8).$
|
||||
* Let $t = G_{c,u}(x).$
|
||||
* If $t \neq \bot$, return $(u, t)$; restart loop otherwise.
|
||||
|
||||
This is implemented in `secp256k1_ellswift_xelligatorswift_var`.
|
||||
|
||||
@@ -269,19 +256,18 @@ Those are then repeated as $c=4$ through $c=7$ for the other sign of $w$ (noting
|
||||
Ignoring the negligible cases, we get:
|
||||
|
||||
**Define** $G_{c,u}(x)$ as:
|
||||
|
||||
- If $c \in \\{0, 1, 4, 5\\}$ (for $x_1$ and $x_2$ formulas):
|
||||
- If $g(-u-x)$ is square, return $\bot$ (as $x_3$ would be valid and take precedence).
|
||||
- If $c \in \\{0, 4\\}$ (the $x_1$ formula) let $v = x$, otherwise let $v = -u-x$ (the $x_2$ formula)
|
||||
- Let $s = -g(u)/(u^2 + uv + v^2 + a)$ (using $s = w^2$ in what follows).
|
||||
- Otherwise, when $c \in \\{2, 3, 6, 7\\}$ (for $x_3$ formulas):
|
||||
- Let $s = x-u.$
|
||||
- Let $r = \sqrt{-s(4g(u) + sh(u))}.$
|
||||
- Let $v = (r/s - u)/2$ if $c \in \\{3, 7\\}$; $(-r/s - u)/2$ otherwise.
|
||||
- Let $w = \sqrt{s}.$
|
||||
- Depending on $c:$
|
||||
- If $c \in \\{0, 1, 2, 3\\}:$ return $P_u^{'-1}(v, w).$
|
||||
- If $c \in \\{4, 5, 6, 7\\}:$ return $P_u^{'-1}(v, -w).$
|
||||
* If $c \in \\{0, 1, 4, 5\\}$ (for $x_1$ and $x_2$ formulas):
|
||||
* If $g(-u-x)$ is square, return $\bot$ (as $x_3$ would be valid and take precedence).
|
||||
* If $c \in \\{0, 4\\}$ (the $x_1$ formula) let $v = x$, otherwise let $v = -u-x$ (the $x_2$ formula)
|
||||
* Let $s = -g(u)/(u^2 + uv + v^2 + a)$ (using $s = w^2$ in what follows).
|
||||
* Otherwise, when $c \in \\{2, 3, 6, 7\\}$ (for $x_3$ formulas):
|
||||
* Let $s = x-u.$
|
||||
* Let $r = \sqrt{-s(4g(u) + sh(u))}.$
|
||||
* Let $v = (r/s - u)/2$ if $c \in \\{3, 7\\}$; $(-r/s - u)/2$ otherwise.
|
||||
* Let $w = \sqrt{s}.$
|
||||
* Depending on $c:$
|
||||
* If $c \in \\{0, 1, 2, 3\\}:$ return $P_u^{'-1}(v, w).$
|
||||
* If $c \in \\{4, 5, 6, 7\\}:$ return $P_u^{'-1}(v, -w).$
|
||||
|
||||
Whenever a square root of a non-square is taken, $\bot$ is returned; for both square roots this happens with roughly
|
||||
50% on random inputs. Similarly, when a division by 0 would occur, $\bot$ is returned as well; this will only happen
|
||||
@@ -298,21 +284,20 @@ transformation. Furthermore, that transformation has no effect on $s$ in the fir
|
||||
as $u^2 + ux + x^2 + a = u^2 + u(-u-x) + (-u-x)^2 + a.$ Thus we can extract it out and move it down:
|
||||
|
||||
**Define** $G_{c,u}(x)$ as:
|
||||
|
||||
- If $c \in \\{0, 1, 4, 5\\}:$
|
||||
- If $g(-u-x)$ is square, return $\bot.$
|
||||
- Let $s = -g(u)/(u^2 + ux + x^2 + a).$
|
||||
- Let $v = x.$
|
||||
- Otherwise, when $c \in \\{2, 3, 6, 7\\}:$
|
||||
- Let $s = x-u.$
|
||||
- Let $r = \sqrt{-s(4g(u) + sh(u))}.$
|
||||
- Let $v = (r/s - u)/2.$
|
||||
- Let $w = \sqrt{s}.$
|
||||
- Depending on $c:$
|
||||
- If $c \in \\{0, 2\\}:$ return $P_u^{'-1}(v, w).$
|
||||
- If $c \in \\{1, 3\\}:$ return $P_u^{'-1}(-u-v, w).$
|
||||
- If $c \in \\{4, 6\\}:$ return $P_u^{'-1}(v, -w).$
|
||||
- If $c \in \\{5, 7\\}:$ return $P_u^{'-1}(-u-v, -w).$
|
||||
* If $c \in \\{0, 1, 4, 5\\}:$
|
||||
* If $g(-u-x)$ is square, return $\bot.$
|
||||
* Let $s = -g(u)/(u^2 + ux + x^2 + a).$
|
||||
* Let $v = x.$
|
||||
* Otherwise, when $c \in \\{2, 3, 6, 7\\}:$
|
||||
* Let $s = x-u.$
|
||||
* Let $r = \sqrt{-s(4g(u) + sh(u))}.$
|
||||
* Let $v = (r/s - u)/2.$
|
||||
* Let $w = \sqrt{s}.$
|
||||
* Depending on $c:$
|
||||
* If $c \in \\{0, 2\\}:$ return $P_u^{'-1}(v, w).$
|
||||
* If $c \in \\{1, 3\\}:$ return $P_u^{'-1}(-u-v, w).$
|
||||
* If $c \in \\{4, 6\\}:$ return $P_u^{'-1}(v, -w).$
|
||||
* If $c \in \\{5, 7\\}:$ return $P_u^{'-1}(-u-v, -w).$
|
||||
|
||||
This shows there will always be exactly 0, 4, or 8 $t$ values for a given $(u, x)$ input.
|
||||
There can be 0, 1, or 2 $(v, w)$ pairs before invoking $P_u^{'-1}$, and each results in 4 distinct $t$ values.
|
||||
@@ -325,60 +310,58 @@ we analyse them here. They generally fall into two categories: cases in which th
|
||||
do not decode back to $x$ (or at least cannot guarantee that they do), and cases in which the encoder might produce the same
|
||||
$t$ value for multiple $c$ inputs (thereby biasing that encoding):
|
||||
|
||||
- In the branch for $x_1$ and $x_2$ (where $c \in \\{0, 1, 4, 5\\}$):
|
||||
- When $g(u) = 0$, we would have $s=w=Y=0$, which is not on $S_u.$ This is only possible on even-ordered curves.
|
||||
* In the branch for $x_1$ and $x_2$ (where $c \in \\{0, 1, 4, 5\\}$):
|
||||
* When $g(u) = 0$, we would have $s=w=Y=0$, which is not on $S_u.$ This is only possible on even-ordered curves.
|
||||
Excluding this also removes the one condition under which the simplified check for $x_3$ on the curve
|
||||
fails (namely when $g(x_1)=g(x_2)=0$ but $g(x_3)$ is not square).
|
||||
This does exclude some valid encodings: when both $g(u)=0$ and $u^2+ux+x^2+a=0$ (also implying $g(x)=0$),
|
||||
the $S_u'$ equation degenerates to $0 = 0$, and many valid $t$ values may exist. Yet, these cannot be targeted uniformly by the
|
||||
encoder anyway as there will generally be more than 8.
|
||||
- When $g(x) = 0$, the same $t$ would be produced as in the $x_3$ branch (where $c \in \\{2, 3, 6, 7\\}$) which we give precedence
|
||||
* When $g(x) = 0$, the same $t$ would be produced as in the $x_3$ branch (where $c \in \\{2, 3, 6, 7\\}$) which we give precedence
|
||||
as it can deal with $g(u)=0$.
|
||||
This is again only possible on even-ordered curves.
|
||||
- In the branch for $x_3$ (where $c \in \\{2, 3, 6, 7\\}$):
|
||||
- When $s=0$, a division by zero would occur.
|
||||
- When $v = -u-v$ and $c \in \\{3, 7\\}$, the same $t$ would be returned as in the $c \in \\{2, 6\\}$ cases.
|
||||
* In the branch for $x_3$ (where $c \in \\{2, 3, 6, 7\\}$):
|
||||
* When $s=0$, a division by zero would occur.
|
||||
* When $v = -u-v$ and $c \in \\{3, 7\\}$, the same $t$ would be returned as in the $c \in \\{2, 6\\}$ cases.
|
||||
It is equivalent to checking whether $r=0$.
|
||||
This cannot occur in the $x_1$ or $x_2$ branches, as it would trigger the $g(-u-x)$ is square condition.
|
||||
A similar concern for $w = -w$ does not exist, as $w=0$ is already impossible in both branches: in the first
|
||||
it requires $g(u)=0$ which is already outlawed on even-ordered curves and impossible on others; in the second it would trigger division by zero.
|
||||
- Curve-specific special cases also exist that need to be rejected, because they result in $(u,t)$ which is invalid to the decoder, or because of division by zero in the encoder:
|
||||
- For $a=0$ curves, when $u=0$ or when $t=0$. The latter can only be reached by the encoder when $g(u)=0$, which requires an even-ordered curve.
|
||||
- For $a \neq 0$ curves, when $X_0(u)=0$, when $h(u)t^2 = -1$, or when $w(u + 2v) = 2X_0(u)$ while also either $w \neq 2Y_0(u)$ or $h(u)=0$.
|
||||
* Curve-specific special cases also exist that need to be rejected, because they result in $(u,t)$ which is invalid to the decoder, or because of division by zero in the encoder:
|
||||
* For $a=0$ curves, when $u=0$ or when $t=0$. The latter can only be reached by the encoder when $g(u)=0$, which requires an even-ordered curve.
|
||||
* For $a \neq 0$ curves, when $X_0(u)=0$, when $h(u)t^2 = -1$, or when $w(u + 2v) = 2X_0(u)$ while also either $w \neq 2Y_0(u)$ or $h(u)=0$.
|
||||
|
||||
**Define** a version of $G_{c,u}(x)$ which deals with all these cases:
|
||||
|
||||
- If $a=0$ and $u=0$, return $\bot.$
|
||||
- If $a \neq 0$ and $X_0(u)=0$, return $\bot.$
|
||||
- If $c \in \\{0, 1, 4, 5\\}:$
|
||||
- If $g(u) = 0$ or $g(x) = 0$, return $\bot$ (even curves only).
|
||||
- If $g(-u-x)$ is square, return $\bot.$
|
||||
- Let $s = -g(u)/(u^2 + ux + x^2 + a)$ (cannot cause division by zero).
|
||||
- Let $v = x.$
|
||||
- Otherwise, when $c \in \\{2, 3, 6, 7\\}:$
|
||||
- Let $s = x-u.$
|
||||
- Let $r = \sqrt{-s(4g(u) + sh(u))}$; return $\bot$ if not square.
|
||||
- If $c \in \\{3, 7\\}$ and $r=0$, return $\bot.$
|
||||
- If $s = 0$, return $\bot.$
|
||||
- Let $v = (r/s - u)/2.$
|
||||
- Let $w = \sqrt{s}$; return $\bot$ if not square.
|
||||
- If $a \neq 0$ and $w(u+2v) = 2X_0(u)$ and either $w \neq 2Y_0(u)$ or $h(u) = 0$, return $\bot.$
|
||||
- Depending on $c:$
|
||||
- If $c \in \\{0, 2\\}$, let $t = P_u^{'-1}(v, w).$
|
||||
- If $c \in \\{1, 3\\}$, let $t = P_u^{'-1}(-u-v, w).$
|
||||
- If $c \in \\{4, 6\\}$, let $t = P_u^{'-1}(v, -w).$
|
||||
- If $c \in \\{5, 7\\}$, let $t = P_u^{'-1}(-u-v, -w).$
|
||||
- If $a=0$ and $t=0$, return $\bot$ (even curves only).
|
||||
- If $a \neq 0$ and $h(u)t^2 = -1$, return $\bot.$
|
||||
- Return $t.$
|
||||
* If $a=0$ and $u=0$, return $\bot.$
|
||||
* If $a \neq 0$ and $X_0(u)=0$, return $\bot.$
|
||||
* If $c \in \\{0, 1, 4, 5\\}:$
|
||||
* If $g(u) = 0$ or $g(x) = 0$, return $\bot$ (even curves only).
|
||||
* If $g(-u-x)$ is square, return $\bot.$
|
||||
* Let $s = -g(u)/(u^2 + ux + x^2 + a)$ (cannot cause division by zero).
|
||||
* Let $v = x.$
|
||||
* Otherwise, when $c \in \\{2, 3, 6, 7\\}:$
|
||||
* Let $s = x-u.$
|
||||
* Let $r = \sqrt{-s(4g(u) + sh(u))}$; return $\bot$ if not square.
|
||||
* If $c \in \\{3, 7\\}$ and $r=0$, return $\bot.$
|
||||
* If $s = 0$, return $\bot.$
|
||||
* Let $v = (r/s - u)/2.$
|
||||
* Let $w = \sqrt{s}$; return $\bot$ if not square.
|
||||
* If $a \neq 0$ and $w(u+2v) = 2X_0(u)$ and either $w \neq 2Y_0(u)$ or $h(u) = 0$, return $\bot.$
|
||||
* Depending on $c:$
|
||||
* If $c \in \\{0, 2\\}$, let $t = P_u^{'-1}(v, w).$
|
||||
* If $c \in \\{1, 3\\}$, let $t = P_u^{'-1}(-u-v, w).$
|
||||
* If $c \in \\{4, 6\\}$, let $t = P_u^{'-1}(v, -w).$
|
||||
* If $c \in \\{5, 7\\}$, let $t = P_u^{'-1}(-u-v, -w).$
|
||||
* If $a=0$ and $t=0$, return $\bot$ (even curves only).
|
||||
* If $a \neq 0$ and $h(u)t^2 = -1$, return $\bot.$
|
||||
* Return $t.$
|
||||
|
||||
Given any $u$, using this algorithm over all $x$ and $c$ values, every $t$ value will be reached exactly once,
|
||||
for an $x$ for which $F_u(t) = x$ holds, except for these cases that will not be reached:
|
||||
|
||||
- All cases where $P_u(t)$ is not defined:
|
||||
- For $a=0$ curves, when $u=0$, $t=0$, or $g(u) = -t^2.$
|
||||
- For $a \neq 0$ curves, when $h(u)t^2 = -1$, $X_0(u) = 0$, or $Y_0(u) (1 - h(u) t^2) = 2X_0(u)t.$
|
||||
- When $g(u)=0$, the potentially many $t$ values that decode to an $x$ satisfying $g(x)=0$ using the $x_2$ formula. These were excluded by the $g(u)=0$ condition in the $c \in \\{0, 1, 4, 5\\}$ branch.
|
||||
* All cases where $P_u(t)$ is not defined:
|
||||
* For $a=0$ curves, when $u=0$, $t=0$, or $g(u) = -t^2.$
|
||||
* For $a \neq 0$ curves, when $h(u)t^2 = -1$, $X_0(u) = 0$, or $Y_0(u) (1 - h(u) t^2) = 2X_0(u)t.$
|
||||
* When $g(u)=0$, the potentially many $t$ values that decode to an $x$ satisfying $g(x)=0$ using the $x_2$ formula. These were excluded by the $g(u)=0$ condition in the $c \in \\{0, 1, 4, 5\\}$ branch.
|
||||
|
||||
These cases form a negligible subset of all $(u, t)$ for cryptographically sized curves.
|
||||
|
||||
@@ -387,42 +370,40 @@ These cases form a negligible subset of all $(u, t)$ for cryptographically sized
|
||||
Specialized for odd-ordered $a=0$ curves:
|
||||
|
||||
**Define** $G_{c,u}(x)$ as:
|
||||
|
||||
- If $u=0$, return $\bot.$
|
||||
- If $c \in \\{0, 1, 4, 5\\}:$
|
||||
- If $(-u-x)^3 + b$ is square, return $\bot$
|
||||
- Let $s = -(u^3 + b)/(u^2 + ux + x^2)$ (cannot cause division by 0).
|
||||
- Let $v = x.$
|
||||
- Otherwise, when $c \in \\{2, 3, 6, 7\\}:$
|
||||
- Let $s = x-u.$
|
||||
- Let $r = \sqrt{-s(4(u^3 + b) + 3su^2)}$; return $\bot$ if not square.
|
||||
- If $c \in \\{3, 7\\}$ and $r=0$, return $\bot.$
|
||||
- If $s = 0$, return $\bot.$
|
||||
- Let $v = (r/s - u)/2.$
|
||||
- Let $w = \sqrt{s}$; return $\bot$ if not square.
|
||||
- Depending on $c:$
|
||||
- If $c \in \\{0, 2\\}:$ return $w(\frac{\sqrt{-3}-1}{2}u - v).$
|
||||
- If $c \in \\{1, 3\\}:$ return $w(\frac{\sqrt{-3}+1}{2}u + v).$
|
||||
- If $c \in \\{4, 6\\}:$ return $w(\frac{-\sqrt{-3}+1}{2}u + v).$
|
||||
- If $c \in \\{5, 7\\}:$ return $w(\frac{-\sqrt{-3}-1}{2}u - v).$
|
||||
* If $u=0$, return $\bot.$
|
||||
* If $c \in \\{0, 1, 4, 5\\}:$
|
||||
* If $(-u-x)^3 + b$ is square, return $\bot$
|
||||
* Let $s = -(u^3 + b)/(u^2 + ux + x^2)$ (cannot cause division by 0).
|
||||
* Let $v = x.$
|
||||
* Otherwise, when $c \in \\{2, 3, 6, 7\\}:$
|
||||
* Let $s = x-u.$
|
||||
* Let $r = \sqrt{-s(4(u^3 + b) + 3su^2)}$; return $\bot$ if not square.
|
||||
* If $c \in \\{3, 7\\}$ and $r=0$, return $\bot.$
|
||||
* If $s = 0$, return $\bot.$
|
||||
* Let $v = (r/s - u)/2.$
|
||||
* Let $w = \sqrt{s}$; return $\bot$ if not square.
|
||||
* Depending on $c:$
|
||||
* If $c \in \\{0, 2\\}:$ return $w(\frac{\sqrt{-3}-1}{2}u - v).$
|
||||
* If $c \in \\{1, 3\\}:$ return $w(\frac{\sqrt{-3}+1}{2}u + v).$
|
||||
* If $c \in \\{4, 6\\}:$ return $w(\frac{-\sqrt{-3}+1}{2}u + v).$
|
||||
* If $c \in \\{5, 7\\}:$ return $w(\frac{-\sqrt{-3}-1}{2}u - v).$
|
||||
|
||||
This is implemented in `secp256k1_ellswift_xswiftec_inv_var`.
|
||||
|
||||
And the x-only ElligatorSwift encoding algorithm is still:
|
||||
|
||||
**Define** _ElligatorSwift(x)_ as:
|
||||
|
||||
- Loop:
|
||||
- Pick a uniformly random field element $u.$
|
||||
- Pick a uniformly random integer $c$ in $[0,8).$
|
||||
- Let $t = G_{c,u}(x).$
|
||||
- If $t \neq \bot$, return $(u, t)$; restart loop otherwise.
|
||||
**Define** *ElligatorSwift(x)* as:
|
||||
* Loop:
|
||||
* Pick a uniformly random field element $u.$
|
||||
* Pick a uniformly random integer $c$ in $[0,8).$
|
||||
* Let $t = G_{c,u}(x).$
|
||||
* If $t \neq \bot$, return $(u, t)$; restart loop otherwise.
|
||||
|
||||
Note that this logic does not take the remapped $u=0$, $t=0$, and $g(u) = -t^2$ cases into account; it just avoids them.
|
||||
While it is not impossible to make the encoder target them, this would increase the maximum number of $t$ values for a given $(u, x)$
|
||||
combination beyond 8, and thereby slow down the ElligatorSwift loop proportionally, for a negligible gain in uniformity.
|
||||
|
||||
## 4. Encoding and decoding full _(x, y)_ coordinates
|
||||
## 4. Encoding and decoding full *(x, y)* coordinates
|
||||
|
||||
So far we have only addressed encoding and decoding x-coordinates, but in some cases an encoding
|
||||
for full points with $(x, y)$ coordinates is desirable. It is possible to encode this information
|
||||
@@ -441,32 +422,30 @@ four distinct $P_u^{'-1}$ calls in the definition of $G_{u,c}.$
|
||||
|
||||
To encode the sign of $y$ in the sign of $Y:$
|
||||
|
||||
**Define** _Decode(u, t)_ for full $(x, y)$ as:
|
||||
|
||||
- Let $(X, Y) = P_u(t).$
|
||||
- Let $x$ be the first value in $(u + 4Y^2, \frac{-X}{2Y} - \frac{u}{2}, \frac{X}{2Y} - \frac{u}{2})$ for which $g(x)$ is square.
|
||||
- Let $y = \sqrt{g(x)}.$
|
||||
- If $sign(y) = sign(Y)$, return $(x, y)$; otherwise return $(x, -y).$
|
||||
**Define** *Decode(u, t)* for full $(x, y)$ as:
|
||||
* Let $(X, Y) = P_u(t).$
|
||||
* Let $x$ be the first value in $(u + 4Y^2, \frac{-X}{2Y} - \frac{u}{2}, \frac{X}{2Y} - \frac{u}{2})$ for which $g(x)$ is square.
|
||||
* Let $y = \sqrt{g(x)}.$
|
||||
* If $sign(y) = sign(Y)$, return $(x, y)$; otherwise return $(x, -y).$
|
||||
|
||||
And encoding would be done using a $G_{c,u}(x, y)$ function defined as:
|
||||
|
||||
**Define** $G_{c,u}(x, y)$ as:
|
||||
|
||||
- If $c \in \\{0, 1\\}:$
|
||||
- If $g(u) = 0$ or $g(x) = 0$, return $\bot$ (even curves only).
|
||||
- If $g(-u-x)$ is square, return $\bot.$
|
||||
- Let $s = -g(u)/(u^2 + ux + x^2 + a)$ (cannot cause division by zero).
|
||||
- Let $v = x.$
|
||||
- Otherwise, when $c \in \\{2, 3\\}:$
|
||||
- Let $s = x-u.$
|
||||
- Let $r = \sqrt{-s(4g(u) + sh(u))}$; return $\bot$ if not square.
|
||||
- If $c = 3$ and $r = 0$, return $\bot.$
|
||||
- Let $v = (r/s - u)/2.$
|
||||
- Let $w = \sqrt{s}$; return $\bot$ if not square.
|
||||
- Let $w' = w$ if $sign(w/2) = sign(y)$; $-w$ otherwise.
|
||||
- Depending on $c:$
|
||||
- If $c \in \\{0, 2\\}:$ return $P_u^{'-1}(v, w').$
|
||||
- If $c \in \\{1, 3\\}:$ return $P_u^{'-1}(-u-v, w').$
|
||||
* If $c \in \\{0, 1\\}:$
|
||||
* If $g(u) = 0$ or $g(x) = 0$, return $\bot$ (even curves only).
|
||||
* If $g(-u-x)$ is square, return $\bot.$
|
||||
* Let $s = -g(u)/(u^2 + ux + x^2 + a)$ (cannot cause division by zero).
|
||||
* Let $v = x.$
|
||||
* Otherwise, when $c \in \\{2, 3\\}:$
|
||||
* Let $s = x-u.$
|
||||
* Let $r = \sqrt{-s(4g(u) + sh(u))}$; return $\bot$ if not square.
|
||||
* If $c = 3$ and $r = 0$, return $\bot.$
|
||||
* Let $v = (r/s - u)/2.$
|
||||
* Let $w = \sqrt{s}$; return $\bot$ if not square.
|
||||
* Let $w' = w$ if $sign(w/2) = sign(y)$; $-w$ otherwise.
|
||||
* Depending on $c:$
|
||||
* If $c \in \\{0, 2\\}:$ return $P_u^{'-1}(v, w').$
|
||||
* If $c \in \\{1, 3\\}:$ return $P_u^{'-1}(-u-v, w').$
|
||||
|
||||
Note that $c$ now only ranges $[0,4)$, as the sign of $w'$ is decided based on that of $y$, rather than on $c.$
|
||||
This change makes some valid encodings unreachable: when $y = 0$ and $sign(Y) \neq sign(0)$.
|
||||
@@ -475,23 +454,22 @@ In the above logic, $sign$ can be implemented in several ways, such as parity of
|
||||
of the input field element (for prime-sized fields) or the quadratic residuosity (for fields where
|
||||
$-1$ is not square). The choice does not matter, as long as it only takes on two possible values, and for $x \neq 0$ it holds that $sign(x) \neq sign(-x)$.
|
||||
|
||||
### 4.1 Full _(x, y)_ coordinates for `secp256k1`
|
||||
### 4.1 Full *(x, y)* coordinates for `secp256k1`
|
||||
|
||||
For $a=0$ curves, there is another option. Note that for those,
|
||||
the $P_u(t)$ function translates negations of $t$ to negations of (both) $X$ and $Y.$ Thus, we can use $sign(t)$ to
|
||||
encode the y-coordinate directly. Combined with the earlier remapping to guarantee all inputs land on the curve, we get
|
||||
as decoder:
|
||||
|
||||
**Define** _Decode(u, t)_ as:
|
||||
|
||||
- Let $u'=u$ if $u \neq 0$; $1$ otherwise.
|
||||
- Let $t'=t$ if $t \neq 0$; $1$ otherwise.
|
||||
- Let $t''=t'$ if $u'^3 + b + t'^2 \neq 0$; $2t'$ otherwise.
|
||||
- Let $X = \dfrac{u'^3 + b - t''^2}{2t''}.$
|
||||
- Let $Y = \dfrac{X + t''}{u'\sqrt{-3}}.$
|
||||
- Let $x$ be the first element of $(u' + 4Y^2, \frac{-X}{2Y} - \frac{u'}{2}, \frac{X}{2Y} - \frac{u'}{2})$ for which $g(x)$ is square.
|
||||
- Let $y = \sqrt{g(x)}.$
|
||||
- Return $(x, y)$ if $sign(y) = sign(t)$; $(x, -y)$ otherwise.
|
||||
**Define** *Decode(u, t)* as:
|
||||
* Let $u'=u$ if $u \neq 0$; $1$ otherwise.
|
||||
* Let $t'=t$ if $t \neq 0$; $1$ otherwise.
|
||||
* Let $t''=t'$ if $u'^3 + b + t'^2 \neq 0$; $2t'$ otherwise.
|
||||
* Let $X = \dfrac{u'^3 + b - t''^2}{2t''}.$
|
||||
* Let $Y = \dfrac{X + t''}{u'\sqrt{-3}}.$
|
||||
* Let $x$ be the first element of $(u' + 4Y^2, \frac{-X}{2Y} - \frac{u'}{2}, \frac{X}{2Y} - \frac{u'}{2})$ for which $g(x)$ is square.
|
||||
* Let $y = \sqrt{g(x)}.$
|
||||
* Return $(x, y)$ if $sign(y) = sign(t)$; $(x, -y)$ otherwise.
|
||||
|
||||
This is implemented in `secp256k1_ellswift_swiftec_var`. The used $sign(x)$ function is the parity of $x$ when represented as in integer in $[0,q).$
|
||||
|
||||
|
||||
3
external/secp256k1/doc/musig.md
vendored
3
external/secp256k1/doc/musig.md
vendored
@@ -1,4 +1,5 @@
|
||||
# Notes on the musig module API
|
||||
Notes on the musig module API
|
||||
===========================
|
||||
|
||||
The following sections contain additional notes on the API of the musig module (`include/secp256k1_musig.h`).
|
||||
A usage example can be found in `examples/musig.c`.
|
||||
|
||||
40
external/secp256k1/doc/release-process.md
vendored
40
external/secp256k1/doc/release-process.md
vendored
@@ -2,7 +2,7 @@
|
||||
|
||||
This document outlines the process for releasing versions of the form `$MAJOR.$MINOR.$PATCH`.
|
||||
|
||||
We distinguish between two types of releases: _regular_ and _maintenance_ releases.
|
||||
We distinguish between two types of releases: *regular* and *maintenance* releases.
|
||||
Regular releases are releases of a new major or minor version as well as patches of the most recent release.
|
||||
Maintenance releases, on the other hand, are required for patches of older releases.
|
||||
|
||||
@@ -15,7 +15,6 @@ This process also assumes that there will be no minor releases for old major rel
|
||||
We aim to cut a regular release every 3-4 months, approximately twice as frequent as major Bitcoin Core releases. Every second release should be published one month before the feature freeze of the next major Bitcoin Core release, allowing sufficient time to update the library in Core.
|
||||
|
||||
## Sanity checks
|
||||
|
||||
Perform these checks when reviewing the release PR (see below):
|
||||
|
||||
1. Ensure `make distcheck` doesn't fail.
|
||||
@@ -43,15 +42,15 @@ Perform these checks when reviewing the release PR (see below):
|
||||
## Regular release
|
||||
|
||||
1. Open a PR to the master branch with a commit (using message `"release: prepare for $MAJOR.$MINOR.$PATCH"`, for example) that
|
||||
- finalizes the release notes in [CHANGELOG.md](../CHANGELOG.md) by
|
||||
- adding a section for the release (make sure that the version number is a link to a diff between the previous and new version),
|
||||
- removing the `[Unreleased]` section header,
|
||||
- ensuring that the release notes are not missing entries (check the `needs-changelog` label on github), and
|
||||
- including an entry for `### ABI Compatibility` if it doesn't exist,
|
||||
- sets `_PKG_VERSION_IS_RELEASE` to `true` in `configure.ac`, and,
|
||||
- if this is not a patch release,
|
||||
- updates `_PKG_VERSION_*` and `_LIB_VERSION_*` in `configure.ac`, and
|
||||
- updates `project(libsecp256k1 VERSION ...)` and `${PROJECT_NAME}_LIB_VERSION_*` in `CMakeLists.txt`.
|
||||
* finalizes the release notes in [CHANGELOG.md](../CHANGELOG.md) by
|
||||
* adding a section for the release (make sure that the version number is a link to a diff between the previous and new version),
|
||||
* removing the `[Unreleased]` section header,
|
||||
* ensuring that the release notes are not missing entries (check the `needs-changelog` label on github), and
|
||||
* including an entry for `### ABI Compatibility` if it doesn't exist,
|
||||
* sets `_PKG_VERSION_IS_RELEASE` to `true` in `configure.ac`, and,
|
||||
* if this is not a patch release,
|
||||
* updates `_PKG_VERSION_*` and `_LIB_VERSION_*` in `configure.ac`, and
|
||||
* updates `project(libsecp256k1 VERSION ...)` and `${PROJECT_NAME}_LIB_VERSION_*` in `CMakeLists.txt`.
|
||||
2. Perform the [sanity checks](#sanity-checks) on the PR branch.
|
||||
3. After the PR is merged, tag the commit, and push the tag:
|
||||
```
|
||||
@@ -60,12 +59,11 @@ Perform these checks when reviewing the release PR (see below):
|
||||
git push git@github.com:bitcoin-core/secp256k1.git v$MAJOR.$MINOR.$PATCH
|
||||
```
|
||||
4. Open a PR to the master branch with a commit (using message `"release cleanup: bump version after $MAJOR.$MINOR.$PATCH"`, for example) that
|
||||
- sets `_PKG_VERSION_IS_RELEASE` to `false` and increments `_PKG_VERSION_PATCH` and `_LIB_VERSION_REVISION` in `configure.ac`,
|
||||
- increments the `$PATCH` component of `project(libsecp256k1 VERSION ...)` and `${PROJECT_NAME}_LIB_VERSION_REVISION` in `CMakeLists.txt`, and
|
||||
- adds an `[Unreleased]` section header to the [CHANGELOG.md](../CHANGELOG.md).
|
||||
* sets `_PKG_VERSION_IS_RELEASE` to `false` and increments `_PKG_VERSION_PATCH` and `_LIB_VERSION_REVISION` in `configure.ac`,
|
||||
* increments the `$PATCH` component of `project(libsecp256k1 VERSION ...)` and `${PROJECT_NAME}_LIB_VERSION_REVISION` in `CMakeLists.txt`, and
|
||||
* adds an `[Unreleased]` section header to the [CHANGELOG.md](../CHANGELOG.md).
|
||||
|
||||
If other maintainers are not present to approve the PR, it can be merged without ACKs.
|
||||
|
||||
5. Create a new GitHub release with a link to the corresponding entry in [CHANGELOG.md](../CHANGELOG.md).
|
||||
6. Send an announcement email to the bitcoin-dev mailing list.
|
||||
|
||||
@@ -79,9 +77,9 @@ Note that bug fixes need to be backported only to releases for which no compatib
|
||||
git push git@github.com:bitcoin-core/secp256k1.git $MAJOR.$MINOR
|
||||
```
|
||||
2. Open a pull request to the `$MAJOR.$MINOR` branch that
|
||||
- includes the bug fixes,
|
||||
- finalizes the release notes similar to a regular release,
|
||||
- increments `_PKG_VERSION_PATCH` and `_LIB_VERSION_REVISION` in `configure.ac`
|
||||
* includes the bug fixes,
|
||||
* finalizes the release notes similar to a regular release,
|
||||
* increments `_PKG_VERSION_PATCH` and `_LIB_VERSION_REVISION` in `configure.ac`
|
||||
and the `$PATCH` component of `project(libsecp256k1 VERSION ...)` and `${PROJECT_NAME}_LIB_VERSION_REVISION` in `CMakeLists.txt`
|
||||
(with commit message `"release: bump versions for $MAJOR.$MINOR.$PATCH"`, for example).
|
||||
3. Perform the [sanity checks](#sanity-checks) on the PR branch.
|
||||
@@ -91,6 +89,6 @@ Note that bug fixes need to be backported only to releases for which no compatib
|
||||
git tag -s v$MAJOR.$MINOR.$PATCH -m "libsecp256k1 $MAJOR.$MINOR.$PATCH"
|
||||
git push git@github.com:bitcoin-core/secp256k1.git v$MAJOR.$MINOR.$PATCH
|
||||
```
|
||||
5. Create a new GitHub release with a link to the corresponding entry in [CHANGELOG.md](../CHANGELOG.md).
|
||||
6. Send an announcement email to the bitcoin-dev mailing list.
|
||||
7. Open PR to the master branch that includes a commit (with commit message `"release notes: add $MAJOR.$MINOR.$PATCH"`, for example) that adds release notes to [CHANGELOG.md](../CHANGELOG.md).
|
||||
6. Create a new GitHub release with a link to the corresponding entry in [CHANGELOG.md](../CHANGELOG.md).
|
||||
7. Send an announcement email to the bitcoin-dev mailing list.
|
||||
8. Open PR to the master branch that includes a commit (with commit message `"release notes: add $MAJOR.$MINOR.$PATCH"`, for example) that adds release notes to [CHANGELOG.md](../CHANGELOG.md).
|
||||
|
||||
301
external/secp256k1/doc/safegcd_implementation.md
vendored
301
external/secp256k1/doc/safegcd_implementation.md
vendored
@@ -29,67 +29,65 @@ def gcd(f, g):
|
||||
return abs(f)
|
||||
```
|
||||
|
||||
It computes the greatest common divisor of an odd integer _f_ and any integer _g_. Its inner loop
|
||||
keeps rewriting the variables _f_ and _g_ alongside a state variable _δ_ that starts at _1_, until
|
||||
_g=0_ is reached. At that point, _|f|_ gives the GCD. Each of the transitions in the loop is called a
|
||||
It computes the greatest common divisor of an odd integer *f* and any integer *g*. Its inner loop
|
||||
keeps rewriting the variables *f* and *g* alongside a state variable *δ* that starts at *1*, until
|
||||
*g=0* is reached. At that point, *|f|* gives the GCD. Each of the transitions in the loop is called a
|
||||
"division step" (referred to as divstep in what follows).
|
||||
|
||||
For example, _gcd(21, 14)_ would be computed as:
|
||||
|
||||
- Start with _δ=1 f=21 g=14_
|
||||
- Take the third branch: _δ=2 f=21 g=7_
|
||||
- Take the first branch: _δ=-1 f=7 g=-7_
|
||||
- Take the second branch: _δ=0 f=7 g=0_
|
||||
- The answer _|f| = 7_.
|
||||
For example, *gcd(21, 14)* would be computed as:
|
||||
- Start with *δ=1 f=21 g=14*
|
||||
- Take the third branch: *δ=2 f=21 g=7*
|
||||
- Take the first branch: *δ=-1 f=7 g=-7*
|
||||
- Take the second branch: *δ=0 f=7 g=0*
|
||||
- The answer *|f| = 7*.
|
||||
|
||||
Why it works:
|
||||
|
||||
- Divsteps can be decomposed into two steps (see paragraph 8.2 in the paper):
|
||||
- (a) If _g_ is odd, replace _(f,g)_ with _(g,g-f)_ or (f,g+f), resulting in an even _g_.
|
||||
- (b) Replace _(f,g)_ with _(f,g/2)_ (where _g_ is guaranteed to be even).
|
||||
- (a) If *g* is odd, replace *(f,g)* with *(g,g-f)* or (f,g+f), resulting in an even *g*.
|
||||
- (b) Replace *(f,g)* with *(f,g/2)* (where *g* is guaranteed to be even).
|
||||
- Neither of those two operations change the GCD:
|
||||
- For (a), assume _gcd(f,g)=c_, then it must be the case that _f=a c_ and _g=b c_ for some integers _a_
|
||||
and _b_. As _(g,g-f)=(b c,(b-a)c)_ and _(f,f+g)=(a c,(a+b)c)_, the result clearly still has
|
||||
common factor _c_. Reasoning in the other direction shows that no common factor can be added by
|
||||
- For (a), assume *gcd(f,g)=c*, then it must be the case that *f=a c* and *g=b c* for some integers *a*
|
||||
and *b*. As *(g,g-f)=(b c,(b-a)c)* and *(f,f+g)=(a c,(a+b)c)*, the result clearly still has
|
||||
common factor *c*. Reasoning in the other direction shows that no common factor can be added by
|
||||
doing so either.
|
||||
- For (b), we know that _f_ is odd, so _gcd(f,g)_ clearly has no factor _2_, and we can remove
|
||||
it from _g_.
|
||||
- The algorithm will eventually converge to _g=0_. This is proven in the paper (see theorem G.3).
|
||||
- It follows that eventually we find a final value _f'_ for which _gcd(f,g) = gcd(f',0)_. As the
|
||||
gcd of _f'_ and _0_ is _|f'|_ by definition, that is our answer.
|
||||
- For (b), we know that *f* is odd, so *gcd(f,g)* clearly has no factor *2*, and we can remove
|
||||
it from *g*.
|
||||
- The algorithm will eventually converge to *g=0*. This is proven in the paper (see theorem G.3).
|
||||
- It follows that eventually we find a final value *f'* for which *gcd(f,g) = gcd(f',0)*. As the
|
||||
gcd of *f'* and *0* is *|f'|* by definition, that is our answer.
|
||||
|
||||
Compared to more [traditional GCD algorithms](https://en.wikipedia.org/wiki/Euclidean_algorithm), this one has the property of only ever looking at
|
||||
the low-order bits of the variables to decide the next steps, and being easy to make
|
||||
constant-time (in more low-level languages than Python). The _δ_ parameter is necessary to
|
||||
constant-time (in more low-level languages than Python). The *δ* parameter is necessary to
|
||||
guide the algorithm towards shrinking the numbers' magnitudes without explicitly needing to look
|
||||
at high order bits.
|
||||
|
||||
Properties that will become important later:
|
||||
|
||||
- Performing more divsteps than needed is not a problem, as _f_ does not change anymore after _g=0_.
|
||||
- Only even numbers are divided by _2_. This means that when reasoning about it algebraically we
|
||||
- Performing more divsteps than needed is not a problem, as *f* does not change anymore after *g=0*.
|
||||
- Only even numbers are divided by *2*. This means that when reasoning about it algebraically we
|
||||
do not need to worry about rounding.
|
||||
- At every point during the algorithm's execution the next _N_ steps only depend on the bottom _N_
|
||||
bits of _f_ and _g_, and on _δ_.
|
||||
- At every point during the algorithm's execution the next *N* steps only depend on the bottom *N*
|
||||
bits of *f* and *g*, and on *δ*.
|
||||
|
||||
|
||||
## 2. From GCDs to modular inverses
|
||||
|
||||
We want an algorithm to compute the inverse _a_ of _x_ modulo _M_, i.e. the number a such that _a x=1
|
||||
mod M_. This inverse only exists if the GCD of _x_ and _M_ is _1_, but that is always the case if _M_ is
|
||||
prime and _0 < x < M_. In what follows, assume that the modular inverse exists.
|
||||
We want an algorithm to compute the inverse *a* of *x* modulo *M*, i.e. the number a such that *a x=1
|
||||
mod M*. This inverse only exists if the GCD of *x* and *M* is *1*, but that is always the case if *M* is
|
||||
prime and *0 < x < M*. In what follows, assume that the modular inverse exists.
|
||||
It turns out this inverse can be computed as a side effect of computing the GCD by keeping track
|
||||
of how the internal variables can be written as linear combinations of the inputs at every step
|
||||
(see the [extended Euclidean algorithm](https://en.wikipedia.org/wiki/Extended_Euclidean_algorithm)).
|
||||
Since the GCD is _1_, such an algorithm will compute numbers _a_ and _b_ such that a x + b M = 1*.
|
||||
Since the GCD is *1*, such an algorithm will compute numbers *a* and *b* such that a x + b M = 1*.
|
||||
Taking that expression *mod M* gives *a x mod M = 1*, and we see that *a* is the modular inverse of *x
|
||||
mod M\*.
|
||||
mod M*.
|
||||
|
||||
A similar approach can be used to calculate modular inverses using the divsteps-based GCD
|
||||
algorithm shown above, if the modulus _M_ is odd. To do so, compute _gcd(f=M,g=x)_, while keeping
|
||||
track of extra variables _d_ and _e_, for which at every step _d = f/x (mod M)_ and _e = g/x (mod M)_.
|
||||
_f/x_ here means the number which multiplied with _x_ gives _f mod M_. As _f_ and _g_ are initialized to _M_
|
||||
and _x_ respectively, _d_ and _e_ just start off being _0_ (_M/x mod M = 0/x mod M = 0_) and _1_ (_x/x mod M
|
||||
= 1_).
|
||||
algorithm shown above, if the modulus *M* is odd. To do so, compute *gcd(f=M,g=x)*, while keeping
|
||||
track of extra variables *d* and *e*, for which at every step *d = f/x (mod M)* and *e = g/x (mod M)*.
|
||||
*f/x* here means the number which multiplied with *x* gives *f mod M*. As *f* and *g* are initialized to *M*
|
||||
and *x* respectively, *d* and *e* just start off being *0* (*M/x mod M = 0/x mod M = 0*) and *1* (*x/x mod M
|
||||
= 1*).
|
||||
|
||||
```python
|
||||
def div2(M, x):
|
||||
@@ -121,16 +119,17 @@ def modinv(M, x):
|
||||
return (d * f) % M
|
||||
```
|
||||
|
||||
Also note that this approach to track _d_ and _e_ throughout the computation to determine the inverse
|
||||
Also note that this approach to track *d* and *e* throughout the computation to determine the inverse
|
||||
is different from the paper. There (see paragraph 12.1 in the paper) a transition matrix for the
|
||||
entire computation is determined (see section 3 below) and the inverse is computed from that.
|
||||
The approach here avoids the need for 2x2 matrix multiplications of various sizes, and appears to
|
||||
be faster at the level of optimization we're able to do in C.
|
||||
|
||||
|
||||
## 3. Batching multiple divsteps
|
||||
|
||||
Every divstep can be expressed as a matrix multiplication, applying a transition matrix _(1/2 t)_
|
||||
to both vectors _[f, g]_ and _[d, e]_ (see paragraph 8.1 in the paper):
|
||||
Every divstep can be expressed as a matrix multiplication, applying a transition matrix *(1/2 t)*
|
||||
to both vectors *[f, g]* and *[d, e]* (see paragraph 8.1 in the paper):
|
||||
|
||||
```
|
||||
t = [ u, v ]
|
||||
@@ -143,15 +142,15 @@ to both vectors _[f, g]_ and _[d, e]_ (see paragraph 8.1 in the paper):
|
||||
[ out_e ] [ in_e ]
|
||||
```
|
||||
|
||||
where _(u, v, q, r)_ is _(0, 2, -1, 1)_, _(2, 0, 1, 1)_, or _(2, 0, 0, 1)_, depending on which branch is
|
||||
taken. As above, the resulting _f_ and _g_ are always integers.
|
||||
where *(u, v, q, r)* is *(0, 2, -1, 1)*, *(2, 0, 1, 1)*, or *(2, 0, 0, 1)*, depending on which branch is
|
||||
taken. As above, the resulting *f* and *g* are always integers.
|
||||
|
||||
Performing multiple divsteps corresponds to a multiplication with the product of all the
|
||||
individual divsteps' transition matrices. As each transition matrix consists of integers
|
||||
divided by _2_, the product of these matrices will consist of integers divided by _2<sup>N</sup>_ (see also
|
||||
theorem 9.2 in the paper). These divisions are expensive when updating _d_ and _e_, so we delay
|
||||
them: we compute the integer coefficients of the combined transition matrix scaled by _2<sup>N</sup>_, and
|
||||
do one division by _2<sup>N</sup>_ as a final step:
|
||||
divided by *2*, the product of these matrices will consist of integers divided by *2<sup>N</sup>* (see also
|
||||
theorem 9.2 in the paper). These divisions are expensive when updating *d* and *e*, so we delay
|
||||
them: we compute the integer coefficients of the combined transition matrix scaled by *2<sup>N</sup>*, and
|
||||
do one division by *2<sup>N</sup>* as a final step:
|
||||
|
||||
```python
|
||||
def divsteps_n_matrix(delta, f, g):
|
||||
@@ -167,13 +166,13 @@ def divsteps_n_matrix(delta, f, g):
|
||||
return delta, (u, v, q, r)
|
||||
```
|
||||
|
||||
As the branches in the divsteps are completely determined by the bottom _N_ bits of _f_ and _g_, this
|
||||
As the branches in the divsteps are completely determined by the bottom *N* bits of *f* and *g*, this
|
||||
function to compute the transition matrix only needs to see those bottom bits. Furthermore all
|
||||
intermediate results and outputs fit in _(N+1)_-bit numbers (unsigned for _f_ and _g_; signed for _u_, _v_,
|
||||
_q_, and _r_) (see also paragraph 8.3 in the paper). This means that an implementation using 64-bit
|
||||
integers could set _N=62_ and compute the full transition matrix for 62 steps at once without any
|
||||
intermediate results and outputs fit in *(N+1)*-bit numbers (unsigned for *f* and *g*; signed for *u*, *v*,
|
||||
*q*, and *r*) (see also paragraph 8.3 in the paper). This means that an implementation using 64-bit
|
||||
integers could set *N=62* and compute the full transition matrix for 62 steps at once without any
|
||||
big integer arithmetic at all. This is the reason why this algorithm is efficient: it only needs
|
||||
to update the full-size _f_, _g_, _d_, and _e_ numbers once every _N_ steps.
|
||||
to update the full-size *f*, *g*, *d*, and *e* numbers once every *N* steps.
|
||||
|
||||
We still need functions to compute:
|
||||
|
||||
@@ -185,8 +184,8 @@ We still need functions to compute:
|
||||
[ out_e ] ( [ q, r ]) [ in_e ]
|
||||
```
|
||||
|
||||
Because the divsteps transformation only ever divides even numbers by two, the result of _t [f,g]_ is always even. When _t_ is a composition of _N_ divsteps, it follows that the resulting _f_
|
||||
and _g_ will be multiple of _2<sup>N</sup>_, and division by _2<sup>N</sup>_ is simply shifting them down:
|
||||
Because the divsteps transformation only ever divides even numbers by two, the result of *t [f,g]* is always even. When *t* is a composition of *N* divsteps, it follows that the resulting *f*
|
||||
and *g* will be multiple of *2<sup>N</sup>*, and division by *2<sup>N</sup>* is simply shifting them down:
|
||||
|
||||
```python
|
||||
def update_fg(f, g, t):
|
||||
@@ -200,8 +199,8 @@ def update_fg(f, g, t):
|
||||
return cf >> N, cg >> N
|
||||
```
|
||||
|
||||
The same is not true for _d_ and _e_, and we need an equivalent of the `div2` function for division by _2<sup>N</sup> mod M_.
|
||||
This is easy if we have precomputed _1/M mod 2<sup>N</sup>_ (which always exists for odd _M_):
|
||||
The same is not true for *d* and *e*, and we need an equivalent of the `div2` function for division by *2<sup>N</sup> mod M*.
|
||||
This is easy if we have precomputed *1/M mod 2<sup>N</sup>* (which always exists for odd *M*):
|
||||
|
||||
```python
|
||||
def div2n(M, Mi, x):
|
||||
@@ -225,7 +224,7 @@ def update_de(d, e, t, M, Mi):
|
||||
return div2n(M, Mi, cd), div2n(M, Mi, ce)
|
||||
```
|
||||
|
||||
With all of those, we can write a version of `modinv` that performs _N_ divsteps at once:
|
||||
With all of those, we can write a version of `modinv` that performs *N* divsteps at once:
|
||||
|
||||
```python3
|
||||
def modinv(M, Mi, x):
|
||||
@@ -243,19 +242,20 @@ def modinv(M, Mi, x):
|
||||
return (d * f) % M
|
||||
```
|
||||
|
||||
This means that in practice we'll always perform a multiple of _N_ divsteps. This is not a problem
|
||||
because once _g=0_, further divsteps do not affect _f_, _g_, _d_, or _e_ anymore (only _δ_ keeps
|
||||
This means that in practice we'll always perform a multiple of *N* divsteps. This is not a problem
|
||||
because once *g=0*, further divsteps do not affect *f*, *g*, *d*, or *e* anymore (only *δ* keeps
|
||||
increasing). For variable time code such excess iterations will be mostly optimized away in later
|
||||
sections.
|
||||
|
||||
|
||||
## 4. Avoiding modulus operations
|
||||
|
||||
So far, there are two places where we compute a remainder of big numbers modulo _M_: at the end of
|
||||
`div2n` in every `update_de`, and at the very end of `modinv` after potentially negating _d_ due to the
|
||||
sign of _f_. These are relatively expensive operations when done generically.
|
||||
So far, there are two places where we compute a remainder of big numbers modulo *M*: at the end of
|
||||
`div2n` in every `update_de`, and at the very end of `modinv` after potentially negating *d* due to the
|
||||
sign of *f*. These are relatively expensive operations when done generically.
|
||||
|
||||
To deal with the modulus operation in `div2n`, we simply stop requiring _d_ and _e_ to be in range
|
||||
_[0,M)_ all the time. Let's start by inlining `div2n` into `update_de`, and dropping the modulus
|
||||
To deal with the modulus operation in `div2n`, we simply stop requiring *d* and *e* to be in range
|
||||
*[0,M)* all the time. Let's start by inlining `div2n` into `update_de`, and dropping the modulus
|
||||
operation at the end:
|
||||
|
||||
```python
|
||||
@@ -272,15 +272,15 @@ def update_de(d, e, t, M, Mi):
|
||||
return cd >> N, ce >> N
|
||||
```
|
||||
|
||||
Let's look at bounds on the ranges of these numbers. It can be shown that _|u|+|v|_ and _|q|+|r|_
|
||||
never exceed _2<sup>N</sup>_ (see paragraph 8.3 in the paper), and thus a multiplication with _t_ will have
|
||||
outputs whose absolute values are at most _2<sup>N</sup>_ times the maximum absolute input value. In case the
|
||||
inputs _d_ and _e_ are in _(-M,M)_, which is certainly true for the initial values _d=0_ and _e=1_ assuming
|
||||
_M > 1_, the multiplication results in numbers in range _(-2<sup>N</sup>M,2<sup>N</sup>M)_. Subtracting less than _2<sup>N</sup>_
|
||||
times _M_ to cancel out _N_ bits brings that up to _(-2<sup>N+1</sup>M,2<sup>N</sup>M)_, and
|
||||
dividing by _2<sup>N</sup>_ at the end takes it to _(-2M,M)_. Another application of `update_de` would take that
|
||||
to _(-3M,2M)_, and so forth. This progressive expansion of the variables' ranges can be
|
||||
counteracted by incrementing _d_ and _e_ by _M_ whenever they're negative:
|
||||
Let's look at bounds on the ranges of these numbers. It can be shown that *|u|+|v|* and *|q|+|r|*
|
||||
never exceed *2<sup>N</sup>* (see paragraph 8.3 in the paper), and thus a multiplication with *t* will have
|
||||
outputs whose absolute values are at most *2<sup>N</sup>* times the maximum absolute input value. In case the
|
||||
inputs *d* and *e* are in *(-M,M)*, which is certainly true for the initial values *d=0* and *e=1* assuming
|
||||
*M > 1*, the multiplication results in numbers in range *(-2<sup>N</sup>M,2<sup>N</sup>M)*. Subtracting less than *2<sup>N</sup>*
|
||||
times *M* to cancel out *N* bits brings that up to *(-2<sup>N+1</sup>M,2<sup>N</sup>M)*, and
|
||||
dividing by *2<sup>N</sup>* at the end takes it to *(-2M,M)*. Another application of `update_de` would take that
|
||||
to *(-3M,2M)*, and so forth. This progressive expansion of the variables' ranges can be
|
||||
counteracted by incrementing *d* and *e* by *M* whenever they're negative:
|
||||
|
||||
```python
|
||||
...
|
||||
@@ -293,12 +293,12 @@ counteracted by incrementing _d_ and _e_ by _M_ whenever they're negative:
|
||||
...
|
||||
```
|
||||
|
||||
With inputs in _(-2M,M)_, they will first be shifted into range _(-M,M)_, which means that the
|
||||
output will again be in _(-2M,M)_, and this remains the case regardless of how many `update_de`
|
||||
With inputs in *(-2M,M)*, they will first be shifted into range *(-M,M)*, which means that the
|
||||
output will again be in *(-2M,M)*, and this remains the case regardless of how many `update_de`
|
||||
invocations there are. In what follows, we will try to make this more efficient.
|
||||
|
||||
Note that increasing _d_ by _M_ is equal to incrementing _cd_ by _u M_ and _ce_ by _q M_. Similarly,
|
||||
increasing _e_ by _M_ is equal to incrementing _cd_ by _v M_ and _ce_ by _r M_. So we could instead write:
|
||||
Note that increasing *d* by *M* is equal to incrementing *cd* by *u M* and *ce* by *q M*. Similarly,
|
||||
increasing *e* by *M* is equal to incrementing *cd* by *v M* and *ce* by *r M*. So we could instead write:
|
||||
|
||||
```python
|
||||
...
|
||||
@@ -318,10 +318,10 @@ increasing _e_ by _M_ is equal to incrementing _cd_ by _v M_ and _ce_ by
|
||||
...
|
||||
```
|
||||
|
||||
Now note that we have two steps of corrections to _cd_ and _ce_ that add multiples of _M_: this
|
||||
Now note that we have two steps of corrections to *cd* and *ce* that add multiples of *M*: this
|
||||
increment, and the decrement that cancels out bottom bits. The second one depends on the first
|
||||
one, but they can still be efficiently combined by only computing the bottom bits of _cd_ and _ce_
|
||||
at first, and using that to compute the final _md_, _me_ values:
|
||||
one, but they can still be efficiently combined by only computing the bottom bits of *cd* and *ce*
|
||||
at first, and using that to compute the final *md*, *me* values:
|
||||
|
||||
```python
|
||||
def update_de(d, e, t, M, Mi):
|
||||
@@ -346,8 +346,8 @@ def update_de(d, e, t, M, Mi):
|
||||
return cd >> N, ce >> N
|
||||
```
|
||||
|
||||
One last optimization: we can avoid the _md M_ and _me M_ multiplications in the bottom bits of _cd_
|
||||
and _ce_ by moving them to the _md_ and _me_ correction:
|
||||
One last optimization: we can avoid the *md M* and *me M* multiplications in the bottom bits of *cd*
|
||||
and *ce* by moving them to the *md* and *me* correction:
|
||||
|
||||
```python
|
||||
...
|
||||
@@ -362,10 +362,10 @@ and _ce_ by moving them to the _md_ and _me_ correction:
|
||||
...
|
||||
```
|
||||
|
||||
The resulting function takes _d_ and _e_ in range _(-2M,M)_ as inputs, and outputs values in the same
|
||||
range. That also means that the _d_ value at the end of `modinv` will be in that range, while we want
|
||||
a result in _[0,M)_. To do that, we need a normalization function. It's easy to integrate the
|
||||
conditional negation of _d_ (based on the sign of _f_) into it as well:
|
||||
The resulting function takes *d* and *e* in range *(-2M,M)* as inputs, and outputs values in the same
|
||||
range. That also means that the *d* value at the end of `modinv` will be in that range, while we want
|
||||
a result in *[0,M)*. To do that, we need a normalization function. It's easy to integrate the
|
||||
conditional negation of *d* (based on the sign of *f*) into it as well:
|
||||
|
||||
```python
|
||||
def normalize(sign, v, M):
|
||||
@@ -391,21 +391,22 @@ And calling it in `modinv` is simply:
|
||||
return normalize(f, d, M)
|
||||
```
|
||||
|
||||
|
||||
## 5. Constant-time operation
|
||||
|
||||
The primary selling point of the algorithm is fast constant-time operation. What code flow still
|
||||
depends on the input data so far?
|
||||
|
||||
- the number of iterations of the while _g ≠ 0_ loop in `modinv`
|
||||
- the number of iterations of the while *g ≠ 0* loop in `modinv`
|
||||
- the branches inside `divsteps_n_matrix`
|
||||
- the sign checks in `update_de`
|
||||
- the sign checks in `normalize`
|
||||
|
||||
To make the while loop in `modinv` constant time it can be replaced with a constant number of
|
||||
iterations. The paper proves (Theorem 11.2) that _741_ divsteps are sufficient for any _256_-bit
|
||||
inputs, and [safegcd-bounds](https://github.com/sipa/safegcd-bounds) shows that the slightly better bound _724_ is
|
||||
sufficient even. Given that every loop iteration performs _N_ divsteps, it will run a total of
|
||||
_⌈724/N⌉_ times.
|
||||
iterations. The paper proves (Theorem 11.2) that *741* divsteps are sufficient for any *256*-bit
|
||||
inputs, and [safegcd-bounds](https://github.com/sipa/safegcd-bounds) shows that the slightly better bound *724* is
|
||||
sufficient even. Given that every loop iteration performs *N* divsteps, it will run a total of
|
||||
*⌈724/N⌉* times.
|
||||
|
||||
To deal with the branches in `divsteps_n_matrix` we will replace them with constant-time bitwise
|
||||
operations (and hope the C compiler isn't smart enough to turn them back into branches; see
|
||||
@@ -424,10 +425,10 @@ divstep can be written instead as (compare to the inner loop of `gcd` in section
|
||||
```
|
||||
|
||||
To convert the above to bitwise operations, we rely on a trick to negate conditionally: per the
|
||||
definition of negative numbers in two's complement, (_-v == ~v + 1_) holds for every number _v_. As
|
||||
_-1_ in two's complement is all _1_ bits, bitflipping can be expressed as xor with _-1_. It follows
|
||||
that _-v == (v ^ -1) - (-1)_. Thus, if we have a variable _c_ that takes on values _0_ or _-1_, then
|
||||
_(v ^ c) - c_ is _v_ if _c=0_ and _-v_ if _c=-1_.
|
||||
definition of negative numbers in two's complement, (*-v == ~v + 1*) holds for every number *v*. As
|
||||
*-1* in two's complement is all *1* bits, bitflipping can be expressed as xor with *-1*. It follows
|
||||
that *-v == (v ^ -1) - (-1)*. Thus, if we have a variable *c* that takes on values *0* or *-1*, then
|
||||
*(v ^ c) - c* is *v* if *c=0* and *-v* if *c=-1*.
|
||||
|
||||
Using this we can write:
|
||||
|
||||
@@ -443,13 +444,13 @@ in constant-time form as:
|
||||
x = (f ^ c1) - c1
|
||||
```
|
||||
|
||||
To use that trick, we need a helper mask variable _c1_ that resolves the condition _δ>0_ to _-1_
|
||||
(if true) or _0_ (if false). We compute _c1_ using right shifting, which is equivalent to dividing by
|
||||
the specified power of _2_ and rounding down (in Python, and also in C under the assumption of a typical two's complement system; see
|
||||
`assumptions.h` for tests that this is the case). Right shifting by _63_ thus maps all
|
||||
numbers in range _[-2<sup>63</sup>,0)_ to _-1_, and numbers in range _[0,2<sup>63</sup>)_ to _0_.
|
||||
To use that trick, we need a helper mask variable *c1* that resolves the condition *δ>0* to *-1*
|
||||
(if true) or *0* (if false). We compute *c1* using right shifting, which is equivalent to dividing by
|
||||
the specified power of *2* and rounding down (in Python, and also in C under the assumption of a typical two's complement system; see
|
||||
`assumptions.h` for tests that this is the case). Right shifting by *63* thus maps all
|
||||
numbers in range *[-2<sup>63</sup>,0)* to *-1*, and numbers in range *[0,2<sup>63</sup>)* to *0*.
|
||||
|
||||
Using the facts that _x&0=0_ and _x&(-1)=x_ (on two's complement systems again), we can write:
|
||||
Using the facts that *x&0=0* and *x&(-1)=x* (on two's complement systems again), we can write:
|
||||
|
||||
```python
|
||||
if g & 1:
|
||||
@@ -497,8 +498,8 @@ becomes:
|
||||
```
|
||||
|
||||
It turns out that this can be implemented more efficiently by applying the substitution
|
||||
_η=-δ_. In this representation, negating _δ_ corresponds to negating _η_, and incrementing
|
||||
_δ_ corresponds to decrementing _η_. This allows us to remove the negation in the _c1_
|
||||
*η=-δ*. In this representation, negating *δ* corresponds to negating *η*, and incrementing
|
||||
*δ* corresponds to decrementing *η*. This allows us to remove the negation in the *c1*
|
||||
computation:
|
||||
|
||||
```python
|
||||
@@ -518,12 +519,12 @@ computation:
|
||||
g >>= 1
|
||||
```
|
||||
|
||||
A variant of divsteps with better worst-case performance can be used instead: starting _δ_ at
|
||||
_1/2_ instead of _1_. This reduces the worst case number of iterations to _590_ for _256_-bit inputs
|
||||
(which can be shown using convex hull analysis). In this case, the substitution _ζ=-(δ+1/2)_
|
||||
is used instead to keep the variable integral. Incrementing _δ_ by _1_ still translates to
|
||||
decrementing _ζ_ by _1_, but negating _δ_ now corresponds to going from _ζ_ to _-(ζ+1)_, or
|
||||
_~ζ_. Doing that conditionally based on _c3_ is simply:
|
||||
A variant of divsteps with better worst-case performance can be used instead: starting *δ* at
|
||||
*1/2* instead of *1*. This reduces the worst case number of iterations to *590* for *256*-bit inputs
|
||||
(which can be shown using convex hull analysis). In this case, the substitution *ζ=-(δ+1/2)*
|
||||
is used instead to keep the variable integral. Incrementing *δ* by *1* still translates to
|
||||
decrementing *ζ* by *1*, but negating *δ* now corresponds to going from *ζ* to *-(ζ+1)*, or
|
||||
*~ζ*. Doing that conditionally based on *c3* is simply:
|
||||
|
||||
```python
|
||||
...
|
||||
@@ -533,12 +534,13 @@ _~ζ_. Doing that conditionally based on _c3_ is simply:
|
||||
```
|
||||
|
||||
By replacing the loop in `divsteps_n_matrix` with a variant of the divstep code above (extended to
|
||||
also apply all _f_ operations to _u_, _v_ and all _g_ operations to _q_, _r_), a constant-time version of
|
||||
also apply all *f* operations to *u*, *v* and all *g* operations to *q*, *r*), a constant-time version of
|
||||
`divsteps_n_matrix` is obtained. The full code will be in section 7.
|
||||
|
||||
These bit fiddling tricks can also be used to make the conditional negations and additions in
|
||||
`update_de` and `normalize` constant-time.
|
||||
|
||||
|
||||
## 6. Variable-time optimizations
|
||||
|
||||
In section 5, we modified the `divsteps_n_matrix` function (and a few others) to be constant time.
|
||||
@@ -548,7 +550,7 @@ faster non-constant time `divsteps_n_matrix` function.
|
||||
|
||||
To do so, first consider yet another way of writing the inner loop of divstep operations in
|
||||
`gcd` from section 1. This decomposition is also explained in the paper in section 8.2. We use
|
||||
the original version with initial _δ=1_ and _η=-δ_ here.
|
||||
the original version with initial *δ=1* and *η=-δ* here.
|
||||
|
||||
```python
|
||||
for _ in range(N):
|
||||
@@ -560,7 +562,7 @@ for _ in range(N):
|
||||
g >>= 1
|
||||
```
|
||||
|
||||
Whenever _g_ is even, the loop only shifts _g_ down and decreases _η_. When _g_ ends in multiple zero
|
||||
Whenever *g* is even, the loop only shifts *g* down and decreases *η*. When *g* ends in multiple zero
|
||||
bits, these iterations can be consolidated into one step. This requires counting the bottom zero
|
||||
bits efficiently, which is possible on most platforms; it is abstracted here as the function
|
||||
`count_trailing_zeros`.
|
||||
@@ -593,20 +595,20 @@ while True:
|
||||
# g is even now, and the eta decrement and g shift will happen in the next loop.
|
||||
```
|
||||
|
||||
We can now remove multiple bottom _0_ bits from _g_ at once, but still need a full iteration whenever
|
||||
there is a bottom _1_ bit. In what follows, we will get rid of multiple _1_ bits simultaneously as
|
||||
We can now remove multiple bottom *0* bits from *g* at once, but still need a full iteration whenever
|
||||
there is a bottom *1* bit. In what follows, we will get rid of multiple *1* bits simultaneously as
|
||||
well.
|
||||
|
||||
Observe that as long as _η ≥ 0_, the loop does not modify _f_. Instead, it cancels out bottom
|
||||
bits of _g_ and shifts them out, and decreases _η_ and _i_ accordingly - interrupting only when _η_
|
||||
becomes negative, or when _i_ reaches _0_. Combined, this is equivalent to adding a multiple of _f_ to
|
||||
_g_ to cancel out multiple bottom bits, and then shifting them out.
|
||||
Observe that as long as *η ≥ 0*, the loop does not modify *f*. Instead, it cancels out bottom
|
||||
bits of *g* and shifts them out, and decreases *η* and *i* accordingly - interrupting only when *η*
|
||||
becomes negative, or when *i* reaches *0*. Combined, this is equivalent to adding a multiple of *f* to
|
||||
*g* to cancel out multiple bottom bits, and then shifting them out.
|
||||
|
||||
It is easy to find what that multiple is: we want a number _w_ such that _g+w f_ has a few bottom
|
||||
zero bits. If that number of bits is _L_, we want _g+w f mod 2<sup>L</sup> = 0_, or _w = -g/f mod 2<sup>L</sup>_. Since _f_
|
||||
is odd, such a _w_ exists for any _L_. _L_ cannot be more than _i_ steps (as we'd finish the loop before
|
||||
doing more) or more than _η+1_ steps (as we'd run `eta, f, g = -eta, g, -f` at that point), but
|
||||
apart from that, we're only limited by the complexity of computing _w_.
|
||||
It is easy to find what that multiple is: we want a number *w* such that *g+w f* has a few bottom
|
||||
zero bits. If that number of bits is *L*, we want *g+w f mod 2<sup>L</sup> = 0*, or *w = -g/f mod 2<sup>L</sup>*. Since *f*
|
||||
is odd, such a *w* exists for any *L*. *L* cannot be more than *i* steps (as we'd finish the loop before
|
||||
doing more) or more than *η+1* steps (as we'd run `eta, f, g = -eta, g, -f` at that point), but
|
||||
apart from that, we're only limited by the complexity of computing *w*.
|
||||
|
||||
This code demonstrates how to cancel up to 4 bits per step:
|
||||
|
||||
@@ -640,25 +642,26 @@ some can be found in Hacker's Delight second edition by Henry S. Warren, Jr. pag
|
||||
Here we need the negated modular inverse, which is a simple transformation of those:
|
||||
|
||||
- Instead of a 3-bit table:
|
||||
- _-f_ or _f ^ 6_
|
||||
- *-f* or *f ^ 6*
|
||||
- Instead of a 4-bit table:
|
||||
- _1 - f(f + 1)_
|
||||
- _-(f + (((f + 1) & 4) << 1))_
|
||||
- For larger tables the following technique can be used: if _w=-1/f mod 2<sup>L</sup>_, then _w(w f+2)_ is
|
||||
_-1/f mod 2<sup>2L</sup>_. This allows extending the previous formulas (or tables). In particular we
|
||||
- *1 - f(f + 1)*
|
||||
- *-(f + (((f + 1) & 4) << 1))*
|
||||
- For larger tables the following technique can be used: if *w=-1/f mod 2<sup>L</sup>*, then *w(w f+2)* is
|
||||
*-1/f mod 2<sup>2L</sup>*. This allows extending the previous formulas (or tables). In particular we
|
||||
have this 6-bit function (based on the 3-bit function above):
|
||||
- _f(f<sup>2</sup> - 2)_
|
||||
- *f(f<sup>2</sup> - 2)*
|
||||
|
||||
This loop, again extended to also handle _u_, _v_, _q_, and _r_ alongside _f_ and _g_, placed in
|
||||
This loop, again extended to also handle *u*, *v*, *q*, and *r* alongside *f* and *g*, placed in
|
||||
`divsteps_n_matrix`, gives a significantly faster, but non-constant time version.
|
||||
|
||||
|
||||
## 7. Final Python version
|
||||
|
||||
All together we need the following functions:
|
||||
|
||||
- A way to compute the transition matrix in constant time, using the `divsteps_n_matrix` function
|
||||
from section 2, but with its loop replaced by a variant of the constant-time divstep from
|
||||
section 5, extended to handle _u_, _v_, _q_, _r_:
|
||||
section 5, extended to handle *u*, *v*, *q*, *r*:
|
||||
|
||||
```python
|
||||
def divsteps_n_matrix(zeta, f, g):
|
||||
@@ -681,7 +684,7 @@ def divsteps_n_matrix(zeta, f, g):
|
||||
return zeta, (u, v, q, r)
|
||||
```
|
||||
|
||||
- The functions to update _f_ and _g_, and _d_ and _e_, from section 2 and section 4, with the constant-time
|
||||
- The functions to update *f* and *g*, and *d* and *e*, from section 2 and section 4, with the constant-time
|
||||
changes to `update_de` from section 5:
|
||||
|
||||
```python
|
||||
@@ -720,7 +723,7 @@ def normalize(sign, v, M):
|
||||
return v
|
||||
```
|
||||
|
||||
- And finally the `modinv` function too, adapted to use _ζ_ instead of _δ_, and using the fixed
|
||||
- And finally the `modinv` function too, adapted to use *ζ* instead of *δ*, and using the fixed
|
||||
iteration count from section 5:
|
||||
|
||||
```python
|
||||
@@ -769,21 +772,20 @@ def modinv_var(M, Mi, x):
|
||||
|
||||
## 8. From GCDs to Jacobi symbol
|
||||
|
||||
We can also use a similar approach to calculate Jacobi symbol _(x | M)_ by keeping track of an
|
||||
extra variable _j_, for which at every step _(x | M) = j (g | f)_. As we update _f_ and _g_, we
|
||||
make corresponding updates to _j_ using
|
||||
We can also use a similar approach to calculate Jacobi symbol *(x | M)* by keeping track of an
|
||||
extra variable *j*, for which at every step *(x | M) = j (g | f)*. As we update *f* and *g*, we
|
||||
make corresponding updates to *j* using
|
||||
[properties of the Jacobi symbol](https://en.wikipedia.org/wiki/Jacobi_symbol#Properties):
|
||||
* *((g/2) | f)* is either *(g | f)* or *-(g | f)*, depending on the value of *f mod 8* (negating if it's *3* or *5*).
|
||||
* *(f | g)* is either *(g | f)* or *-(g | f)*, depending on *f mod 4* and *g mod 4* (negating if both are *3*).
|
||||
|
||||
- _((g/2) | f)_ is either _(g | f)_ or _-(g | f)_, depending on the value of _f mod 8_ (negating if it's _3_ or _5_).
|
||||
- _(f | g)_ is either _(g | f)_ or _-(g | f)_, depending on _f mod 4_ and _g mod 4_ (negating if both are _3_).
|
||||
|
||||
These updates depend only on the values of _f_ and _g_ modulo _4_ or _8_, and can thus be applied
|
||||
very quickly, as long as we keep track of a few additional bits of _f_ and _g_. Overall, this
|
||||
These updates depend only on the values of *f* and *g* modulo *4* or *8*, and can thus be applied
|
||||
very quickly, as long as we keep track of a few additional bits of *f* and *g*. Overall, this
|
||||
calculation is slightly simpler than the one for the modular inverse because we no longer need to
|
||||
keep track of _d_ and _e_.
|
||||
keep track of *d* and *e*.
|
||||
|
||||
However, one difficulty of this approach is that the Jacobi symbol _(a | n)_ is only defined for
|
||||
positive odd integers _n_, whereas in the original safegcd algorithm, _f, g_ can take negative
|
||||
However, one difficulty of this approach is that the Jacobi symbol *(a | n)* is only defined for
|
||||
positive odd integers *n*, whereas in the original safegcd algorithm, *f, g* can take negative
|
||||
values. We resolve this by using the following modified steps:
|
||||
|
||||
```python
|
||||
@@ -797,16 +799,15 @@ values. We resolve this by using the following modified steps:
|
||||
```
|
||||
|
||||
The algorithm is still correct, since the changed divstep, called a "posdivstep" (see section 8.4
|
||||
and E.5 in the paper) preserves _gcd(f, g)_. However, there's no proof that the modified algorithm
|
||||
and E.5 in the paper) preserves *gcd(f, g)*. However, there's no proof that the modified algorithm
|
||||
will converge. The justification for posdivsteps is completely empirical: in practice, it appears
|
||||
that the vast majority of nonzero inputs converge to _f=g=gcd(f<sub>0</sub>, g<sub>0</sub>)_ in a
|
||||
that the vast majority of nonzero inputs converge to *f=g=gcd(f<sub>0</sub>, g<sub>0</sub>)* in a
|
||||
number of steps proportional to their logarithm.
|
||||
|
||||
Note that:
|
||||
|
||||
- We require inputs to satisfy _gcd(x, M) = 1_, as otherwise _f=1_ is not reached.
|
||||
- We require inputs _x &neq; 0_, because applying posdivstep with _g=0_ has no effect.
|
||||
- We need to update the termination condition from _g=0_ to _f=1_.
|
||||
- We require inputs to satisfy *gcd(x, M) = 1*, as otherwise *f=1* is not reached.
|
||||
- We require inputs *x &neq; 0*, because applying posdivstep with *g=0* has no effect.
|
||||
- We need to update the termination condition from *g=0* to *f=1*.
|
||||
|
||||
We account for the possibility of nonconvergence by only performing a bounded number of
|
||||
posdivsteps, and then falling back to square-root based Jacobi calculation if a solution has not
|
||||
@@ -814,5 +815,5 @@ yet been found.
|
||||
|
||||
The optimizations in sections 3-7 above are described in the context of the original divsteps, but
|
||||
in the C implementation we also adapt most of them (not including "avoiding modulus operations",
|
||||
since it's not necessary to track _d, e_, and "constant-time operation", since we never calculate
|
||||
since it's not necessary to track *d, e*, and "constant-time operation", since we never calculate
|
||||
Jacobi symbols for secret data) to the posdivsteps version.
|
||||
|
||||
File diff suppressed because one or more lines are too long
@@ -6,9 +6,7 @@ option java_multiple_files = true;
|
||||
|
||||
import "org/xrpl/rpc/v1/ledger.proto";
|
||||
|
||||
message GetLedgerRequest
|
||||
{
|
||||
|
||||
message GetLedgerRequest {
|
||||
LedgerSpecifier ledger = 1;
|
||||
|
||||
// If true, include transactions contained in this ledger
|
||||
@@ -38,12 +36,10 @@ message GetLedgerRequest
|
||||
bool get_object_neighbors = 7;
|
||||
}
|
||||
|
||||
message GetLedgerResponse
|
||||
{
|
||||
message GetLedgerResponse {
|
||||
bytes ledger_header = 1;
|
||||
|
||||
oneof transactions
|
||||
{
|
||||
oneof transactions {
|
||||
// Just the hashes
|
||||
TransactionHashList hashes_list = 2;
|
||||
|
||||
@@ -70,25 +66,21 @@ message GetLedgerResponse
|
||||
// map diff
|
||||
bool object_neighbors_included = 9;
|
||||
|
||||
|
||||
// Successor information for book directories modified as part of this
|
||||
// ledger
|
||||
repeated BookSuccessor book_successors = 10;
|
||||
}
|
||||
|
||||
message TransactionHashList
|
||||
{
|
||||
message TransactionHashList {
|
||||
repeated bytes hashes = 1;
|
||||
}
|
||||
|
||||
message TransactionAndMetadata
|
||||
{
|
||||
message TransactionAndMetadata {
|
||||
bytes transaction_blob = 1;
|
||||
|
||||
bytes metadata_blob = 2;
|
||||
}
|
||||
|
||||
message TransactionAndMetadataList
|
||||
{
|
||||
message TransactionAndMetadataList {
|
||||
repeated TransactionAndMetadata transactions = 1;
|
||||
}
|
||||
|
||||
@@ -8,8 +8,7 @@ import "org/xrpl/rpc/v1/ledger.proto";
|
||||
|
||||
// Get ledger objects for a specific ledger. You can iterate through several
|
||||
// calls to retrieve the entire contents of a single ledger version.
|
||||
message GetLedgerDataRequest
|
||||
{
|
||||
message GetLedgerDataRequest {
|
||||
// If set, only objects with a key greater than marker are returned.
|
||||
// This can be used to pick up where a previous call left off.
|
||||
// Set marker to the value of marker in the previous response.
|
||||
@@ -31,8 +30,7 @@ message GetLedgerDataRequest
|
||||
string user = 6;
|
||||
}
|
||||
|
||||
message GetLedgerDataResponse
|
||||
{
|
||||
message GetLedgerDataResponse {
|
||||
// Sequence of the ledger containing the returned ledger objects
|
||||
uint32 ledger_index = 1;
|
||||
|
||||
@@ -50,4 +48,3 @@ message GetLedgerDataResponse
|
||||
// True if request was exempt from resource controls
|
||||
bool is_unlimited = 7;
|
||||
}
|
||||
|
||||
|
||||
@@ -6,10 +6,8 @@ option java_multiple_files = true;
|
||||
|
||||
import "org/xrpl/rpc/v1/ledger.proto";
|
||||
|
||||
|
||||
// Get the state map difference between the two specified ledgers
|
||||
message GetLedgerDiffRequest
|
||||
{
|
||||
message GetLedgerDiffRequest {
|
||||
LedgerSpecifier base_ledger = 1;
|
||||
|
||||
LedgerSpecifier desired_ledger = 2;
|
||||
@@ -23,10 +21,8 @@ message GetLedgerDiffRequest
|
||||
string client_ip = 4;
|
||||
}
|
||||
|
||||
message GetLedgerDiffResponse
|
||||
{
|
||||
message GetLedgerDiffResponse {
|
||||
// All ledger objects that were added, modified or deleted between
|
||||
// base_ledger and desired_ledger
|
||||
RawLedgerObjects ledger_objects = 1;
|
||||
}
|
||||
|
||||
|
||||
@@ -7,8 +7,7 @@ option java_multiple_files = true;
|
||||
import "org/xrpl/rpc/v1/ledger.proto";
|
||||
|
||||
// Get a single ledger object
|
||||
message GetLedgerEntryRequest
|
||||
{
|
||||
message GetLedgerEntryRequest {
|
||||
// Key of the desired object
|
||||
bytes key = 1;
|
||||
|
||||
@@ -21,8 +20,7 @@ message GetLedgerEntryRequest
|
||||
string client_ip = 3;
|
||||
}
|
||||
|
||||
message GetLedgerEntryResponse
|
||||
{
|
||||
message GetLedgerEntryResponse {
|
||||
RawLedgerObject ledger_object = 1;
|
||||
|
||||
// Ledger containing the object. Will match the value specified in the
|
||||
|
||||
@@ -5,19 +5,16 @@ option java_package = "org.xrpl.rpc.v1";
|
||||
option java_multiple_files = true;
|
||||
|
||||
// Next field: 4
|
||||
message LedgerSpecifier
|
||||
{
|
||||
message LedgerSpecifier {
|
||||
// Next field: 4
|
||||
enum Shortcut
|
||||
{
|
||||
enum Shortcut {
|
||||
SHORTCUT_UNSPECIFIED = 0;
|
||||
SHORTCUT_VALIDATED = 1;
|
||||
SHORTCUT_CLOSED = 2;
|
||||
SHORTCUT_CURRENT = 3;
|
||||
}
|
||||
|
||||
oneof ledger
|
||||
{
|
||||
oneof ledger {
|
||||
Shortcut shortcut = 1;
|
||||
uint32 sequence = 2;
|
||||
// 32 bytes
|
||||
@@ -25,10 +22,8 @@ message LedgerSpecifier
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
// Next field: 3
|
||||
message RawLedgerObject
|
||||
{
|
||||
message RawLedgerObject {
|
||||
// Raw data of the ledger object. In GetLedgerResponse and
|
||||
// GetLedgerDiffResponse, data will be empty if the object was deleted.
|
||||
bytes data = 1;
|
||||
@@ -36,8 +31,7 @@ message RawLedgerObject
|
||||
// Key of the ledger object
|
||||
bytes key = 2;
|
||||
|
||||
enum ModificationType
|
||||
{
|
||||
enum ModificationType {
|
||||
UNSPECIFIED = 0;
|
||||
CREATED = 1;
|
||||
MODIFIED = 2;
|
||||
@@ -54,8 +48,7 @@ message RawLedgerObject
|
||||
bytes successor = 5;
|
||||
}
|
||||
|
||||
message RawLedgerObjects
|
||||
{
|
||||
message RawLedgerObjects {
|
||||
repeated RawLedgerObject objects = 1;
|
||||
}
|
||||
|
||||
@@ -63,13 +56,10 @@ message RawLedgerObjects
|
||||
// an actual object, yet we need to be able to ask for the successor to the
|
||||
// book base.
|
||||
message BookSuccessor {
|
||||
|
||||
// Base of the book in question
|
||||
bytes book_base = 1;
|
||||
|
||||
// First book directory in the book. An empty value here means the entire
|
||||
// book is deleted
|
||||
bytes first_book = 2;
|
||||
|
||||
};
|
||||
|
||||
|
||||
@@ -9,13 +9,11 @@ import "org/xrpl/rpc/v1/get_ledger_entry.proto";
|
||||
import "org/xrpl/rpc/v1/get_ledger_data.proto";
|
||||
import "org/xrpl/rpc/v1/get_ledger_diff.proto";
|
||||
|
||||
|
||||
// These methods are binary only methods for retrieiving arbitrary ledger state
|
||||
// via gRPC. These methods are used by clio, but can also be
|
||||
// used by any client that wants to extract ledger state in an efficient manner.
|
||||
// They do not directly mimic the JSON equivalent methods.
|
||||
service XRPLedgerAPIService {
|
||||
|
||||
// Get a specific ledger, optionally including transactions and any modified,
|
||||
// added or deleted ledger objects
|
||||
rpc GetLedger(GetLedgerRequest) returns (GetLedgerResponse);
|
||||
@@ -29,5 +27,4 @@ service XRPLedgerAPIService {
|
||||
// Get all ledger objects that are different between the two specified
|
||||
// ledgers. Note, this method has no JSON equivalent.
|
||||
rpc GetLedgerDiff(GetLedgerDiffRequest) returns (GetLedgerDiffResponse);
|
||||
|
||||
}
|
||||
|
||||
@@ -4,8 +4,7 @@ package protocol;
|
||||
// Unused numbers in the list below may have been used previously. Please don't
|
||||
// reassign them for reuse unless you are 100% certain that there won't be a
|
||||
// conflict. Even if you're sure, it's probably best to assign a new type.
|
||||
enum MessageType
|
||||
{
|
||||
enum MessageType {
|
||||
mtMANIFESTS = 2;
|
||||
mtPING = 3;
|
||||
mtCLUSTER = 5;
|
||||
@@ -36,25 +35,22 @@ enum MessageType
|
||||
//------------------------------------------------------------------------------
|
||||
|
||||
/* Provides the current ephemeral key for a validator. */
|
||||
message TMManifest
|
||||
{
|
||||
message TMManifest {
|
||||
// A Manifest object in the Ripple serialization format.
|
||||
required bytes stobject = 1;
|
||||
}
|
||||
|
||||
message TMManifests
|
||||
{
|
||||
message TMManifests {
|
||||
repeated TMManifest list = 1;
|
||||
|
||||
// The manifests sent when a peer first connects to another peer are `history`.
|
||||
optional bool history = 2 [deprecated=true];
|
||||
optional bool history = 2 [deprecated = true];
|
||||
}
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
|
||||
// The status of a node in our cluster
|
||||
message TMClusterNode
|
||||
{
|
||||
message TMClusterNode {
|
||||
required string publicKey = 1;
|
||||
required uint32 reportTime = 2;
|
||||
required uint32 nodeLoad = 3;
|
||||
@@ -63,29 +59,25 @@ message TMClusterNode
|
||||
}
|
||||
|
||||
// Sources that are placing load on the server
|
||||
message TMLoadSource
|
||||
{
|
||||
message TMLoadSource {
|
||||
required string name = 1;
|
||||
required uint32 cost = 2;
|
||||
optional uint32 count = 3; // number of connections
|
||||
}
|
||||
|
||||
// The status of all nodes in the cluster
|
||||
message TMCluster
|
||||
{
|
||||
message TMCluster {
|
||||
repeated TMClusterNode clusterNodes = 1;
|
||||
repeated TMLoadSource loadSources = 2;
|
||||
}
|
||||
|
||||
// Node public key
|
||||
message TMLink
|
||||
{
|
||||
required bytes nodePubKey = 1 [deprecated=true]; // node public key
|
||||
message TMLink {
|
||||
required bytes nodePubKey = 1 [deprecated = true]; // node public key
|
||||
}
|
||||
|
||||
// Peer public key
|
||||
message TMPublicKey
|
||||
{
|
||||
message TMPublicKey {
|
||||
required bytes publicKey = 1;
|
||||
}
|
||||
|
||||
@@ -93,8 +85,7 @@ message TMPublicKey
|
||||
// If you want to send an amount that is greater than any single address of yours
|
||||
// you must first combine coins from one address to another.
|
||||
|
||||
enum TransactionStatus
|
||||
{
|
||||
enum TransactionStatus {
|
||||
tsNEW = 1; // origin node did/could not validate
|
||||
tsCURRENT = 2; // scheduled to go in this ledger
|
||||
tsCOMMITED = 3; // in a closed ledger
|
||||
@@ -105,22 +96,18 @@ enum TransactionStatus
|
||||
tsHELD_LEDGER = 8; // held for future ledger
|
||||
}
|
||||
|
||||
message TMTransaction
|
||||
{
|
||||
message TMTransaction {
|
||||
required bytes rawTransaction = 1;
|
||||
required TransactionStatus status = 2;
|
||||
optional uint64 receiveTimestamp = 3;
|
||||
optional bool deferred = 4; // not applied to open ledger
|
||||
}
|
||||
|
||||
message TMTransactions
|
||||
{
|
||||
message TMTransactions {
|
||||
repeated TMTransaction transactions = 1;
|
||||
}
|
||||
|
||||
|
||||
enum NodeStatus
|
||||
{
|
||||
enum NodeStatus {
|
||||
nsCONNECTING = 1; // acquiring connections
|
||||
nsCONNECTED = 2; // convinced we are connected to the real network
|
||||
nsMONITORING = 3; // we know what the previous ledger is
|
||||
@@ -128,16 +115,14 @@ enum NodeStatus
|
||||
nsSHUTTING = 5; // node is shutting down
|
||||
}
|
||||
|
||||
enum NodeEvent
|
||||
{
|
||||
enum NodeEvent {
|
||||
neCLOSING_LEDGER = 1; // closing a ledger because its close time has come
|
||||
neACCEPTED_LEDGER = 2; // accepting a closed ledger, we have finished computing it
|
||||
neSWITCHED_LEDGER = 3; // changing due to network consensus
|
||||
neLOST_SYNC = 4;
|
||||
}
|
||||
|
||||
message TMStatusChange
|
||||
{
|
||||
message TMStatusChange {
|
||||
optional NodeStatus newStatus = 1;
|
||||
optional NodeEvent newEvent = 2;
|
||||
optional uint32 ledgerSeq = 3;
|
||||
@@ -148,10 +133,8 @@ message TMStatusChange
|
||||
optional uint32 lastSeq = 8;
|
||||
}
|
||||
|
||||
|
||||
// Announce to the network our position on a closing ledger
|
||||
message TMProposeSet
|
||||
{
|
||||
message TMProposeSet {
|
||||
required uint32 proposeSeq = 1;
|
||||
required bytes currentTxHash = 2; // the hash of the ledger we are proposing
|
||||
required bytes nodePubKey = 3;
|
||||
@@ -162,28 +145,25 @@ message TMProposeSet
|
||||
repeated bytes removedTransactions = 11; // not required if number is large
|
||||
|
||||
// node vouches signature is correct
|
||||
optional bool checkedSignature = 7 [deprecated=true];
|
||||
optional bool checkedSignature = 7 [deprecated = true];
|
||||
|
||||
// Number of hops traveled
|
||||
optional uint32 hops = 12 [deprecated=true];
|
||||
optional uint32 hops = 12 [deprecated = true];
|
||||
}
|
||||
|
||||
enum TxSetStatus
|
||||
{
|
||||
enum TxSetStatus {
|
||||
tsHAVE = 1; // We have this set locally
|
||||
tsCAN_GET = 2; // We have a peer with this set
|
||||
tsNEED = 3; // We need this set and can't get it
|
||||
}
|
||||
|
||||
message TMHaveTransactionSet
|
||||
{
|
||||
message TMHaveTransactionSet {
|
||||
required TxSetStatus status = 1;
|
||||
required bytes hash = 2;
|
||||
}
|
||||
|
||||
// Validator list (UNL)
|
||||
message TMValidatorList
|
||||
{
|
||||
message TMValidatorList {
|
||||
required bytes manifest = 1;
|
||||
required bytes blob = 2;
|
||||
required bytes signature = 3;
|
||||
@@ -191,24 +171,21 @@ message TMValidatorList
|
||||
}
|
||||
|
||||
// Validator List v2
|
||||
message ValidatorBlobInfo
|
||||
{
|
||||
message ValidatorBlobInfo {
|
||||
optional bytes manifest = 1;
|
||||
required bytes blob = 2;
|
||||
required bytes signature = 3;
|
||||
}
|
||||
|
||||
// Collection of Validator List v2 (UNL)
|
||||
message TMValidatorListCollection
|
||||
{
|
||||
message TMValidatorListCollection {
|
||||
required uint32 version = 1;
|
||||
required bytes manifest = 2;
|
||||
repeated ValidatorBlobInfo blobs = 3;
|
||||
}
|
||||
|
||||
// Used to sign a final closed ledger after reprocessing
|
||||
message TMValidation
|
||||
{
|
||||
message TMValidation {
|
||||
// The serialized validation
|
||||
required bytes validation = 1;
|
||||
|
||||
@@ -220,8 +197,7 @@ message TMValidation
|
||||
}
|
||||
|
||||
// An array of Endpoint messages
|
||||
message TMEndpoints
|
||||
{
|
||||
message TMEndpoints {
|
||||
// Previously used - don't reuse.
|
||||
reserved 2;
|
||||
|
||||
@@ -231,16 +207,14 @@ message TMEndpoints
|
||||
|
||||
// An update to the Endpoint type that uses a string
|
||||
// to represent endpoints, thus allowing ipv6 or ipv4 addresses
|
||||
message TMEndpointv2
|
||||
{
|
||||
message TMEndpointv2 {
|
||||
required string endpoint = 1;
|
||||
required uint32 hops = 2;
|
||||
}
|
||||
repeated TMEndpointv2 endpoints_v2 = 3;
|
||||
};
|
||||
|
||||
message TMIndexedObject
|
||||
{
|
||||
message TMIndexedObject {
|
||||
optional bytes hash = 1;
|
||||
optional bytes nodeID = 2;
|
||||
optional bytes index = 3;
|
||||
@@ -248,8 +222,7 @@ message TMIndexedObject
|
||||
optional uint32 ledgerSeq = 5;
|
||||
}
|
||||
|
||||
message TMGetObjectByHash
|
||||
{
|
||||
message TMGetObjectByHash {
|
||||
enum ObjectType {
|
||||
otUNKNOWN = 0;
|
||||
otLEDGER = 1;
|
||||
@@ -269,35 +242,29 @@ message TMGetObjectByHash
|
||||
repeated TMIndexedObject objects = 6; // the specific objects requested
|
||||
}
|
||||
|
||||
|
||||
message TMLedgerNode
|
||||
{
|
||||
message TMLedgerNode {
|
||||
required bytes nodedata = 1;
|
||||
optional bytes nodeid = 2; // missing for ledger base data
|
||||
}
|
||||
|
||||
enum TMLedgerInfoType
|
||||
{
|
||||
enum TMLedgerInfoType {
|
||||
liBASE = 0; // basic ledger info
|
||||
liTX_NODE = 1; // transaction node
|
||||
liAS_NODE = 2; // account state node
|
||||
liTS_CANDIDATE = 3; // candidate transaction set
|
||||
}
|
||||
|
||||
enum TMLedgerType
|
||||
{
|
||||
enum TMLedgerType {
|
||||
ltACCEPTED = 0;
|
||||
ltCURRENT = 1; // no longer supported
|
||||
ltCLOSED = 2;
|
||||
}
|
||||
|
||||
enum TMQueryType
|
||||
{
|
||||
enum TMQueryType {
|
||||
qtINDIRECT = 0;
|
||||
}
|
||||
|
||||
message TMGetLedger
|
||||
{
|
||||
message TMGetLedger {
|
||||
required TMLedgerInfoType itype = 1;
|
||||
optional TMLedgerType ltype = 2;
|
||||
optional bytes ledgerHash = 3; // Can also be the transaction set hash if liTS_CANDIDATE
|
||||
@@ -308,15 +275,13 @@ message TMGetLedger
|
||||
optional uint32 queryDepth = 8; // How deep to go, number of extra levels
|
||||
}
|
||||
|
||||
enum TMReplyError
|
||||
{
|
||||
enum TMReplyError {
|
||||
reNO_LEDGER = 1; // We don't have the ledger you are asking about
|
||||
reNO_NODE = 2; // We don't have any of the nodes you are asking for
|
||||
reBAD_REQUEST = 3; // The request is wrong, e.g. wrong format
|
||||
}
|
||||
|
||||
message TMLedgerData
|
||||
{
|
||||
message TMLedgerData {
|
||||
required bytes ledgerHash = 1;
|
||||
required uint32 ledgerSeq = 2;
|
||||
required TMLedgerInfoType type = 3;
|
||||
@@ -325,8 +290,7 @@ message TMLedgerData
|
||||
optional TMReplyError error = 6;
|
||||
}
|
||||
|
||||
message TMPing
|
||||
{
|
||||
message TMPing {
|
||||
enum pingType {
|
||||
ptPING = 0; // we want a reply
|
||||
ptPONG = 1; // this is a reply
|
||||
@@ -337,28 +301,24 @@ message TMPing
|
||||
optional uint64 netTime = 4;
|
||||
}
|
||||
|
||||
message TMSquelch
|
||||
{
|
||||
message TMSquelch {
|
||||
required bool squelch = 1; // squelch if true, otherwise unsquelch
|
||||
required bytes validatorPubKey = 2; // validator's public key
|
||||
optional uint32 squelchDuration = 3; // squelch duration in seconds
|
||||
}
|
||||
|
||||
enum TMLedgerMapType
|
||||
{
|
||||
enum TMLedgerMapType {
|
||||
lmTRANASCTION = 1; // transaction map
|
||||
lmACCOUNT_STATE = 2; // account state map
|
||||
}
|
||||
|
||||
message TMProofPathRequest
|
||||
{
|
||||
message TMProofPathRequest {
|
||||
required bytes key = 1;
|
||||
required bytes ledgerHash = 2;
|
||||
required TMLedgerMapType type = 3;
|
||||
}
|
||||
|
||||
message TMProofPathResponse
|
||||
{
|
||||
message TMProofPathResponse {
|
||||
required bytes key = 1;
|
||||
required bytes ledgerHash = 2;
|
||||
required TMLedgerMapType type = 3;
|
||||
@@ -367,21 +327,17 @@ message TMProofPathResponse
|
||||
optional TMReplyError error = 6;
|
||||
}
|
||||
|
||||
message TMReplayDeltaRequest
|
||||
{
|
||||
message TMReplayDeltaRequest {
|
||||
required bytes ledgerHash = 1;
|
||||
}
|
||||
|
||||
message TMReplayDeltaResponse
|
||||
{
|
||||
message TMReplayDeltaResponse {
|
||||
required bytes ledgerHash = 1;
|
||||
optional bytes ledgerHeader = 2;
|
||||
repeated bytes transaction = 3;
|
||||
optional TMReplyError error = 4;
|
||||
}
|
||||
|
||||
message TMHaveTransactions
|
||||
{
|
||||
message TMHaveTransactions {
|
||||
repeated bytes hashes = 1;
|
||||
}
|
||||
|
||||
|
||||
Reference in New Issue
Block a user