vexahub/voprf-vx
4
0
Fork 0
Code Issues 1 Pull Requests Actions Releases 5 Activity

Initial implementation (#1)

Browse Source
This commit is contained in:
Kevin Lewi
2021-09-09 01:56:54 -07:00
committed by GitHub
parent 743692882d
commit bb4b9d0909
23 changed files with 2093 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files
.github/workflows/main.yml
+87
View File
@@ -0,0 +1,87 @@
name: Rust CI
on:
push:
branches:
- main
pull_request:
types: [opened, repoened, synchronize]
jobs:
test:
runs-on: ubuntu-latest
strategy:
fail-fast: false
matrix:
backend_feature:
- u64_backend
- u32_backend
toolchain:
- stable
- 1.51.0
name: test
steps:
- name: Checkout sources
uses: actions/checkout@v2
- name: Install ${{ matrix.toolchain }} toolchain
uses: actions-rs/toolchain@v1
with:
profile: minimal
toolchain: ${{ matrix.toolchain }}
override: true
components: rustfmt, clippy
- name: Run cargo test
uses: actions-rs/cargo@v1
with:
command: test
args: --no-default-features --features ${{ matrix.backend_feature }}
- name: Run cargo test with std
uses: actions-rs/cargo@v1
with:
command: test
args: --no-default-features --features std --features ${{ matrix.backend_feature }}
clippy:
name: cargo clippy
runs-on: ubuntu-latest
steps:
- name: Checkout sources
uses: actions/checkout@v2
- name: Install stable toolchain
uses: actions-rs/toolchain@v1
with:
profile: minimal
toolchain: stable
override: true
components: rustfmt, clippy
- name: Run cargo clippy
uses: actions-rs/cargo@v1
with:
command: clippy
args: -- -D warnings
format:
name: cargo fmt
runs-on: ubuntu-latest
steps:
- name: Checkout sources
uses: actions/checkout@v2
- name: Install stable toolchain
uses: actions-rs/toolchain@v1
with:
profile: minimal
toolchain: stable
override: true
components: rustfmt, clippy
- name: Run cargo fmt
uses: actions-rs/cargo@v1
with:
command: fmt
args: --all -- --check
.gitignore
+10
View File
@@ -0,0 +1,10 @@
# Generated by Cargo
# will have compiled files and executables
/target/
# Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
# More information here https://doc.rust-lang.org/cargo/guide/cargo-toml-vs-cargo-lock.html
Cargo.lock
# These are backup files generated by rustfmt
**/*.rs.bk
CODE_OF_CONDUCT.md
+76
View File
@@ -0,0 +1,76 @@
# Code of Conduct
## Our Pledge
In the interest of fostering an open and welcoming environment, we as
contributors and maintainers pledge to make participation in our project and
our community a harassment-free experience for everyone, regardless of age, body
size, disability, ethnicity, sex characteristics, gender identity and expression,
level of experience, education, socio-economic status, nationality, personal
appearance, race, religion, or sexual identity and orientation.
## Our Standards
Examples of behavior that contributes to creating a positive environment
include:
* Using welcoming and inclusive language
* Being respectful of differing viewpoints and experiences
* Gracefully accepting constructive criticism
* Focusing on what is best for the community
* Showing empathy towards other community members
Examples of unacceptable behavior by participants include:
* The use of sexualized language or imagery and unwelcome sexual attention or
advances
* Trolling, insulting/derogatory comments, and personal or political attacks
* Public or private harassment
* Publishing others' private information, such as a physical or electronic
address, without explicit permission
* Other conduct which could reasonably be considered inappropriate in a
professional setting
## Our Responsibilities
Project maintainers are responsible for clarifying the standards of acceptable
behavior and are expected to take appropriate and fair corrective action in
response to any instances of unacceptable behavior.
Project maintainers have the right and responsibility to remove, edit, or
reject comments, commits, code, wiki edits, issues, and other contributions
that are not aligned to this Code of Conduct, or to ban temporarily or
permanently any contributor for other behaviors that they deem inappropriate,
threatening, offensive, or harmful.
## Scope
This Code of Conduct applies within all project spaces, and it also applies when
an individual is representing the project or its community in public spaces.
Examples of representing a project or community include using an official
project e-mail address, posting via an official social media account, or acting
as an appointed representative at an online or offline event. Representation of
a project may be further defined and clarified by project maintainers.
## Enforcement
Instances of abusive, harassing, or otherwise unacceptable behavior may be
reported by contacting the project team at <opensource-conduct@fb.com>. All
complaints will be reviewed and investigated and will result in a response that
is deemed necessary and appropriate to the circumstances. The project team is
obligated to maintain confidentiality with regard to the reporter of an incident.
Further details of specific enforcement policies may be posted separately.
Project maintainers who do not follow or enforce the Code of Conduct in good
faith may face temporary or permanent repercussions as determined by other
members of the project's leadership.
## Attribution
This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
available at https://www.contributor-covenant.org/version/1/4/code-of-conduct.html
[homepage]: https://www.contributor-covenant.org
For answers to common questions about this code of conduct, see
https://www.contributor-covenant.org/faq
CONTRIBUTING.md
+30
View File
@@ -0,0 +1,30 @@
# Contributing to this library
We want to make contributing to this project as easy and transparent as
possible.
## Pull Requests
We actively welcome your pull requests.
1. Fork the repo and create your branch from `main`.
2. If you've added code that should be tested, add tests.
3. If you've changed APIs, update the documentation.
4. Ensure the test suite passes.
5. If you haven't already, complete the Contributor License Agreement ("CLA").
## Contributor License Agreement ("CLA")
In order to accept your pull request, we need you to submit a CLA. You only need
to do this once to work on any of Facebook's open source projects.
Complete your CLA here: <https://code.facebook.com/cla>
## Issues
We use GitHub issues to track public bugs. Please ensure your description is
clear and has sufficient instructions to be able to reproduce the issue.
Facebook has a [bounty program](https://www.facebook.com/whitehat/) for the safe
disclosure of security bugs. In those cases, please go through the process
outlined on that page and do not file a public issue.
## License
By contributing to opaque-ke, you agree that your contributions will be
licensed under the LICENSE file in the root directory of this source tree.
Cargo.toml
+39
View File
@@ -0,0 +1,39 @@
[package]
name = "voprf"
version = "0.0.0"
description = "An implementation of a verifiable oblivious pseudorandom function (VOPRF)"
authors = ["Kevin Lewi <[email protected]>"]
license = "MIT"
edition = "2018"
readme = "README.md"
[features]
default = ["u64_backend"]
u64_backend = ["curve25519-dalek/u64_backend"]
u32_backend = ["curve25519-dalek/u32_backend"]
std = ["curve25519-dalek/std", "getrandom", "rand/std", "rand/std_rng"]
[dependencies]
constant_time_eq = "0.1"
curve25519-dalek = { version = "3", default-features = false }
digest = "0.9"
displaydoc = { version = "0.2", default-features = false }
generic-array = "0.14"
getrandom = { version = "0.2", optional = true }
hkdf = "0.11"
hmac = "0.11"
rand = { version = "0.8", default-features = false }
subtle = { version = "2.3", default-features = false }
zeroize = { version = "1", features = ["zeroize_derive"] }
[dev-dependencies]
base64 = "0.13"
bincode = "1"
chacha20poly1305 = "0.8"
criterion = "0.3"
hex = "0.4"
lazy_static = "1"
serde_json = "1"
sha2 = "0.9"
proptest = "1"
rustyline = "8"
LICENSE
+12
View File
@@ -0,0 +1,12 @@
## License
Licensed under either of
* Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
* MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
at your option.
### Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in the work by you, as defined in the Apache-2.0 license, shall
be dual licensed as above, without any additional terms or conditions.
LICENSE-APACHE
+201
View File
@@ -0,0 +1,201 @@
Apache License
Version 2.0, January 2004
http://www.apache.org/licenses/
TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
1. Definitions.
"License" shall mean the terms and conditions for use, reproduction,
and distribution as defined by Sections 1 through 9 of this document.
"Licensor" shall mean the copyright owner or entity authorized by
the copyright owner that is granting the License.
"Legal Entity" shall mean the union of the acting entity and all
other entities that control, are controlled by, or are under common
control with that entity. For the purposes of this definition,
"control" means (i) the power, direct or indirect, to cause the
direction or management of such entity, whether by contract or
otherwise, or (ii) ownership of fifty percent (50%) or more of the
outstanding shares, or (iii) beneficial ownership of such entity.
"You" (or "Your") shall mean an individual or Legal Entity
exercising permissions granted by this License.
"Source" form shall mean the preferred form for making modifications,
including but not limited to software source code, documentation
source, and configuration files.
"Object" form shall mean any form resulting from mechanical
transformation or translation of a Source form, including but
not limited to compiled object code, generated documentation,
and conversions to other media types.
"Work" shall mean the work of authorship, whether in Source or
Object form, made available under the License, as indicated by a
copyright notice that is included in or attached to the work
(an example is provided in the Appendix below).
"Derivative Works" shall mean any work, whether in Source or Object
form, that is based on (or derived from) the Work and for which the
editorial revisions, annotations, elaborations, or other modifications
represent, as a whole, an original work of authorship. For the purposes
of this License, Derivative Works shall not include works that remain
separable from, or merely link (or bind by name) to the interfaces of,
the Work and Derivative Works thereof.
"Contribution" shall mean any work of authorship, including
the original version of the Work and any modifications or additions
to that Work or Derivative Works thereof, that is intentionally
submitted to Licensor for inclusion in the Work by the copyright owner
or by an individual or Legal Entity authorized to submit on behalf of
the copyright owner. For the purposes of this definition, "submitted"
means any form of electronic, verbal, or written communication sent
to the Licensor or its representatives, including but not limited to
communication on electronic mailing lists, source code control systems,
and issue tracking systems that are managed by, or on behalf of, the
Licensor for the purpose of discussing and improving the Work, but
excluding communication that is conspicuously marked or otherwise
designated in writing by the copyright owner as "Not a Contribution."
"Contributor" shall mean Licensor and any individual or Legal Entity
on behalf of whom a Contribution has been received by Licensor and
subsequently incorporated within the Work.
2. Grant of Copyright License. Subject to the terms and conditions of
this License, each Contributor hereby grants to You a perpetual,
worldwide, non-exclusive, no-charge, royalty-free, irrevocable
copyright license to reproduce, prepare Derivative Works of,
publicly display, publicly perform, sublicense, and distribute the
Work and such Derivative Works in Source or Object form.
3. Grant of Patent License. Subject to the terms and conditions of
this License, each Contributor hereby grants to You a perpetual,
worldwide, non-exclusive, no-charge, royalty-free, irrevocable
(except as stated in this section) patent license to make, have made,
use, offer to sell, sell, import, and otherwise transfer the Work,
where such license applies only to those patent claims licensable
by such Contributor that are necessarily infringed by their
Contribution(s) alone or by combination of their Contribution(s)
with the Work to which such Contribution(s) was submitted. If You
institute patent litigation against any entity (including a
cross-claim or counterclaim in a lawsuit) alleging that the Work
or a Contribution incorporated within the Work constitutes direct
or contributory patent infringement, then any patent licenses
granted to You under this License for that Work shall terminate
as of the date such litigation is filed.
4. Redistribution. You may reproduce and distribute copies of the
Work or Derivative Works thereof in any medium, with or without
modifications, and in Source or Object form, provided that You
meet the following conditions:
(a) You must give any other recipients of the Work or
Derivative Works a copy of this License; and
(b) You must cause any modified files to carry prominent notices
stating that You changed the files; and
(c) You must retain, in the Source form of any Derivative Works
that You distribute, all copyright, patent, trademark, and
attribution notices from the Source form of the Work,
excluding those notices that do not pertain to any part of
the Derivative Works; and
(d) If the Work includes a "NOTICE" text file as part of its
distribution, then any Derivative Works that You distribute must
include a readable copy of the attribution notices contained
within such NOTICE file, excluding those notices that do not
pertain to any part of the Derivative Works, in at least one
of the following places: within a NOTICE text file distributed
as part of the Derivative Works; within the Source form or
documentation, if provided along with the Derivative Works; or,
within a display generated by the Derivative Works, if and
wherever such third-party notices normally appear. The contents
of the NOTICE file are for informational purposes only and
do not modify the License. You may add Your own attribution
notices within Derivative Works that You distribute, alongside
or as an addendum to the NOTICE text from the Work, provided
that such additional attribution notices cannot be construed
as modifying the License.
You may add Your own copyright statement to Your modifications and
may provide additional or different license terms and conditions
for use, reproduction, or distribution of Your modifications, or
for any such Derivative Works as a whole, provided Your use,
reproduction, and distribution of the Work otherwise complies with
the conditions stated in this License.
5. Submission of Contributions. Unless You explicitly state otherwise,
any Contribution intentionally submitted for inclusion in the Work
by You to the Licensor shall be under the terms and conditions of
this License, without any additional terms or conditions.
Notwithstanding the above, nothing herein shall supersede or modify
the terms of any separate license agreement you may have executed
with Licensor regarding such Contributions.
6. Trademarks. This License does not grant permission to use the trade
names, trademarks, service marks, or product names of the Licensor,
except as required for reasonable and customary use in describing the
origin of the Work and reproducing the content of the NOTICE file.
7. Disclaimer of Warranty. Unless required by applicable law or
agreed to in writing, Licensor provides the Work (and each
Contributor provides its Contributions) on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
implied, including, without limitation, any warranties or conditions
of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
PARTICULAR PURPOSE. You are solely responsible for determining the
appropriateness of using or redistributing the Work and assume any
risks associated with Your exercise of permissions under this License.
8. Limitation of Liability. In no event and under no legal theory,
whether in tort (including negligence), contract, or otherwise,
unless required by applicable law (such as deliberate and grossly
negligent acts) or agreed to in writing, shall any Contributor be
liable to You for damages, including any direct, indirect, special,
incidental, or consequential damages of any character arising as a
result of this License or out of the use or inability to use the
Work (including but not limited to damages for loss of goodwill,
work stoppage, computer failure or malfunction, or any and all
other commercial damages or losses), even if such Contributor
has been advised of the possibility of such damages.
9. Accepting Warranty or Additional Liability. While redistributing
the Work or Derivative Works thereof, You may choose to offer,
and charge a fee for, acceptance of support, warranty, indemnity,
or other liability obligations and/or rights consistent with this
License. However, in accepting such obligations, You may act only
on Your own behalf and on Your sole responsibility, not on behalf
of any other Contributor, and only if You agree to indemnify,
defend, and hold each Contributor harmless for any liability
incurred by, or claims asserted against, such Contributor by reason
of your accepting any such warranty or additional liability.
END OF TERMS AND CONDITIONS
APPENDIX: How to apply the Apache License to your work.
To apply the Apache License to your work, attach the following
boilerplate notice, with the fields enclosed by brackets "[]"
replaced with your own identifying information. (Don't include
the brackets!) The text should be enclosed in the appropriate
comment syntax for the file format. We also recommend that a
file or class name and description of purpose be included on the
same "printed page" as the copyright notice for easier
identification within third-party archives.
Copyright [yyyy] [name of copyright owner]
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
LICENSE-MIT
+23
View File
@@ -0,0 +1,23 @@
Permission is hereby granted, free of charge, to any
person obtaining a copy of this software and associated
documentation files (the "Software"), to deal in the
Software without restriction, including without
limitation the rights to use, copy, modify, merge,
publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software
is furnished to do so, subject to the following
conditions:
The above copyright notice and this permission notice
shall be included in all copies or substantial portions
of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
README.md
+7 -1
View File
@@ -1 +1,7 @@
# voprf # voprf ![Build Status](https://github.com/novifinancial/voprf/workflows/Rust%20CI/badge.svg)
An implementation of a (verifiable) oblivious pseudorandom function (VOPRF)
License
-------
This project is [licensed](./LICENSE) under either Apache 2.0 or MIT, at your option.
src/ciphersuite.rs
+17
View File
@@ -0,0 +1,17 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
//! Defines the CipherSuite trait to specify the underlying primitives for VOPRF
use crate::{group::Group, hash::Hash};
/// Configures the underlying primitives used in VOPRF
pub trait CipherSuite {
/// A finite cyclic group along with a point representation that allows some
/// customization on how to hash an input to a curve point. See `group::Group`.
type Group: Group;
/// The main hash function to use (for HKDF computations and hashing transcripts).
type Hash: Hash;
}
src/errors.rs
+57
View File
@@ -0,0 +1,57 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
//! A list of error types which are produced during an execution of the protocol
use core::fmt::Debug;
#[cfg(feature = "std")]
use std::error::Error;
use displaydoc::Display;
/// Represents an error in the manipulation of internal cryptographic data
#[derive(Clone, Display, Eq, Hash, PartialEq)]
pub enum InternalError {
/// Could not parse byte sequence for key
InvalidByteSequence,
/// Invalid length for {name}: expected {len}, but is actually {actual_len}.
SizeError {
/// name
name: &'static str,
/// length
len: usize,
/// actual
actual_len: usize,
},
/// Could not decompress point.
PointError,
/// Computing the hash-to-curve function failed
HashToCurveError,
/// Failure to serialize or deserialize bytes
SerializationError,
}
impl Debug for InternalError {
fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
match self {
Self::InvalidByteSequence => f.debug_tuple("InvalidByteSequence").finish(),
Self::SizeError {
name,
len,
actual_len,
} => f
.debug_struct("SizeError")
.field("name", name)
.field("len", len)
.field("actual_len", actual_len)
.finish(),
Self::PointError => f.debug_tuple("PointError").finish(),
Self::HashToCurveError => f.debug_tuple("HashToCurveError").finish(),
Self::SerializationError => f.debug_tuple("SerializationError").finish(),
}
}
}
#[cfg(feature = "std")]
impl Error for InternalError {}
src/group/expand.rs
+190
View File
@@ -0,0 +1,190 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
use crate::errors::InternalError;
use crate::hash::Hash;
use crate::serialization::i2osp;
use alloc::vec::Vec;
use digest::{BlockInput, Digest};
use generic_array::typenum::Unsigned;
// Computes ceil(x / y)
fn div_ceil(x: usize, y: usize) -> usize {
let additive = (x % y != 0) as usize;
x / y + additive
}
fn xor(x: &[u8], y: &[u8]) -> Result<Vec<u8>, InternalError> {
if x.len() != y.len() {
return Err(InternalError::HashToCurveError);
}
Ok(x.iter().zip(y).map(|(&x1, &x2)| x1 ^ x2).collect())
}
/// Corresponds to the expand_message_xmd() function defined in
/// <https://www.ietf.org/archive/id/draft-irtf-cfrg-hash-to-curve-10.txt>
pub fn expand_message_xmd<H: Hash>(
msg: &[u8],
dst: &[u8],
len_in_bytes: usize,
) -> Result<Vec<u8>, InternalError> {
let b_in_bytes = <H as Digest>::OutputSize::USIZE;
let r_in_bytes = <H as BlockInput>::BlockSize::USIZE;
let ell = div_ceil(len_in_bytes, b_in_bytes);
if ell > 255 {
return Err(InternalError::HashToCurveError);
}
let dst_prime = [dst, &i2osp(dst.len(), 1)?].concat();
let z_pad = i2osp(0, r_in_bytes)?;
let l_i_b_str = i2osp(len_in_bytes, 2)?;
let msg_prime = [&z_pad, msg, &l_i_b_str, &i2osp(0, 1)?, &dst_prime].concat();
let mut b: Vec<Vec<u8>> = alloc::vec![H::digest(&msg_prime).to_vec()]; // b[0]
let mut h = H::new();
h.update(&b[0]);
h.update(&i2osp(1, 1)?);
h.update(&dst_prime);
b.push(h.finalize_reset().to_vec()); // b[1]
let mut uniform_bytes: Vec<u8> = Vec::new();
uniform_bytes.extend_from_slice(&b[1]);
for i in 2..(ell + 1) {
h.update(xor(&b[0], &b[i - 1])?);
h.update(&i2osp(i, 1)?);
h.update(&dst_prime);
b.push(h.finalize_reset().to_vec()); // b[i]
uniform_bytes.extend_from_slice(&b[i]);
}
Ok(uniform_bytes[..len_in_bytes].to_vec())
}
#[cfg(test)]
mod tests {
struct Params {
msg: &'static str,
len_in_bytes: usize,
uniform_bytes: &'static str,
}
#[test]
fn test_expand_message_xmd() {
// Test vectors taken from Section K.1 of https://www.ietf.org/archive/id/draft-irtf-cfrg-hash-to-curve-10.txt
let test_vectors: alloc::vec::Vec<Params> = alloc::vec![
Params {
msg: "",
len_in_bytes: 0x20,
uniform_bytes: "f659819a6473c1835b25ea59e3d38914c98b374f0970b7e4c\
92181df928fca88",
},
Params {
msg: "abc",
len_in_bytes: 0x20,
uniform_bytes: "1c38f7c211ef233367b2420d04798fa4698080a8901021a79\
5a1151775fe4da7",
},
Params {
msg: "abcdef0123456789",
len_in_bytes: 0x20,
uniform_bytes: "8f7e7b66791f0da0dbb5ec7c22ec637f79758c0a48170bfb7c4611bd304ece89",
},
Params {
msg: "q128_qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq\
qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq\
qqqqqqqqqqqqqqqqqqqqqqqqq",
len_in_bytes: 0x20,
uniform_bytes: "72d5aa5ec810370d1f0013c0df2f1d65699494ee2a39f72e\
1716b1b964e1c642",
},
Params {
msg: "a512_aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
len_in_bytes: 0x20,
uniform_bytes: "3b8e704fc48336aca4c2a12195b720882f2162a4b7b13a9c\
350db46f429b771b",
},
Params {
msg: "",
len_in_bytes: 0x80,
uniform_bytes: "8bcffd1a3cae24cf9cd7ab85628fd111bb17e3739d3b53f8\
9580d217aa79526f1708354a76a402d3569d6a9d19ef3de4d0b991\
e4f54b9f20dcde9b95a66824cbdf6c1a963a1913d43fd7ac443a02\
fc5d9d8d77e2071b86ab114a9f34150954a7531da568a1ea8c7608\
61c0cde2005afc2c114042ee7b5848f5303f0611cf297f",
},
Params {
msg: "abc",
len_in_bytes: 0x80,
uniform_bytes: "fe994ec51bdaa821598047b3121c149b364b178606d5e72b\
fbb713933acc29c186f316baecf7ea22212f2496ef3f785a27e84a\
40d8b299cec56032763eceeff4c61bd1fe65ed81decafff4a31d01\
98619c0aa0c6c51fca15520789925e813dcfd318b542f879944127\
1f4db9ee3b8092a7a2e8d5b75b73e28fb1ab6b4573c192",
},
Params {
msg: "abcdef0123456789",
len_in_bytes: 0x80,
uniform_bytes: "c9ec7941811b1e19ce98e21db28d22259354d4d0643e3011\
75e2f474e030d32694e9dd5520dde93f3600d8edad94e5c3649030\
88a7228cc9eff685d7eaac50d5a5a8229d083b51de4ccc3733917f\
4b9535a819b445814890b7029b5de805bf62b33a4dc7e24acdf2c9\
24e9fe50d55a6b832c8c84c7f82474b34e48c6d43867be",
},
Params {
msg: "q128_qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq\
qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq\
qqqqqqqqqqqqqqqqqqqqqqqqq",
len_in_bytes: 0x80,
uniform_bytes: "48e256ddba722053ba462b2b93351fc966026e6d6db49318\
9798181c5f3feea377b5a6f1d8368d7453faef715f9aecb078cd40\
2cbd548c0e179c4ed1e4c7e5b048e0a39d31817b5b24f50db58bb3\
720fe96ba53db947842120a068816ac05c159bb5266c63658b4f00\
0cbf87b1209a225def8ef1dca917bcda79a1e42acd8069",
},
Params {
msg: "a512_aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
len_in_bytes: 0x80,
uniform_bytes: "396962db47f749ec3b5042ce2452b619607f27fd3939ece2\
746a7614fb83a1d097f554df3927b084e55de92c7871430d6b95c2\
a13896d8a33bc48587b1f66d21b128a1a8240d5b0c26dfe795a1a8\
42a0807bb148b77c2ef82ed4b6c9f7fcb732e7f94466c8b51e52bf\
378fba044a31f5cb44583a892f5969dcd73b3fa128816e",
},
];
let dst = "QUUX-V01-CS02-with-expander";
for tv in test_vectors {
let uniform_bytes = super::expand_message_xmd::<sha2::Sha256>(
tv.msg.as_bytes(),
dst.as_bytes(),
tv.len_in_bytes,
)
.unwrap();
assert_eq!(tv.uniform_bytes, hex::encode(uniform_bytes));
}
}
}
src/group/mod.rs
+78
View File
@@ -0,0 +1,78 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
//! Defines the Group trait to specify the underlying prime order group used in
//! OPAQUE's OPRF
mod expand;
#[cfg(feature = "p256")]
pub(crate) mod p256;
mod ristretto;
mod x25519;
use crate::errors::InternalError;
use crate::hash::Hash;
use core::ops::Mul;
use generic_array::{ArrayLength, GenericArray};
use rand::{CryptoRng, RngCore};
use zeroize::Zeroize;
/// A prime-order subgroup of a base field (EC, prime-order field ...). This
/// subgroup is noted additively — as in the draft RFC — in this trait.
pub trait Group: Copy + Sized + for<'a> Mul<&'a <Self as Group>::Scalar, Output = Self> {
/// The ciphersuite identifier as dictated by
/// <https://www.ietf.org/archive/id/draft-irtf-cfrg-voprf-05.txt>
const SUITE_ID: usize;
/// transforms a password and domain separation tag (DST) into a curve point
fn map_to_curve<H: Hash>(msg: &[u8], dst: &[u8]) -> Result<Self, InternalError>;
/// Hashes a slice of pseudo-random bytes to a scalar
fn hash_to_scalar<H: Hash>(input: &[u8], dst: &[u8]) -> Result<Self::Scalar, InternalError>;
/// Generates the contextString parameter as defined in
/// <https://www.ietf.org/archive/id/draft-irtf-cfrg-voprf-05.txt>
fn get_context_string(mode: u8) -> Result<alloc::vec::Vec<u8>, InternalError> {
use crate::serialization::i2osp;
Ok([i2osp(mode as usize, 1)?, i2osp(Self::SUITE_ID, 2)?].concat())
}
/// The type of base field scalars
type Scalar: Zeroize + Copy;
/// The byte length necessary to represent scalars
type ScalarLen: ArrayLength<u8> + 'static;
/// Return a scalar from its fixed-length bytes representation
fn from_scalar_slice(
scalar_bits: &GenericArray<u8, Self::ScalarLen>,
) -> Result<Self::Scalar, InternalError>;
/// picks a scalar at random
fn random_nonzero_scalar<R: RngCore + CryptoRng>(rng: &mut R) -> Self::Scalar;
/// Serializes a scalar to bytes
fn scalar_as_bytes(scalar: Self::Scalar) -> GenericArray<u8, Self::ScalarLen>;
/// The multiplicative inverse of this scalar
fn scalar_invert(scalar: &Self::Scalar) -> Self::Scalar;
/// The byte length necessary to represent group elements
type ElemLen: ArrayLength<u8> + 'static;
/// Return an element from its fixed-length bytes representation
fn from_element_slice(
element_bits: &GenericArray<u8, Self::ElemLen>,
) -> Result<Self, InternalError>;
/// Serializes the `self` group element
fn to_arr(&self) -> GenericArray<u8, Self::ElemLen>;
/// Get the base point for the group
fn base_point() -> Self;
/// Multiply the point by a scalar, represented as a slice
fn mult_by_slice(&self, scalar: &GenericArray<u8, Self::ScalarLen>) -> Self;
/// Returns if the group element is equal to the identity (1)
fn is_identity(&self) -> bool;
/// Compares in constant time if the group elements are equal
fn ct_equal(&self, other: &Self) -> bool;
}
src/group/p256.rs
+537
View File
@@ -0,0 +1,537 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
#![allow(
clippy::borrow_interior_mutable_const,
clippy::declare_interior_mutable_const
)]
use super::Group;
use crate::errors::{InternalError, ProtocolError};
use crate::hash::Hash;
use core::ops::{Add, Div, Mul, Neg, Sub};
use core::str::FromStr;
use generic_array::typenum::{U32, U33};
use generic_array::{ArrayLength, GenericArray};
use num_bigint::{BigInt, Sign};
use num_integer::Integer;
use num_traits::{One, ToPrimitive};
use once_cell::unsync::Lazy;
use p256_::elliptic_curve::group::prime::PrimeCurveAffine;
use p256_::elliptic_curve::group::GroupEncoding;
use p256_::elliptic_curve::sec1::{FromEncodedPoint, ToEncodedPoint};
use p256_::elliptic_curve::subtle::ConstantTimeEq;
use p256_::elliptic_curve::Field;
use p256_::{AffinePoint, EncodedPoint, ProjectivePoint};
use rand::{CryptoRng, RngCore};
// `L: 48`
pub const L: usize = 48;
impl Group for ProjectivePoint {
const SUITE_ID: usize = 0x0003;
// Implements the `hash_to_curve()` function from
// https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-hash-to-curve-11#section-3
fn map_to_curve<H: Hash>(msg: &[u8], dst: &[u8]) -> Result<Self, ProtocolError> {
// https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-hash-to-curve-11#section-8.2
// `p: 2^256 - 2^224 + 2^192 + 2^96 - 1`
const P: Lazy<BigInt> = Lazy::new(|| {
BigInt::from_str(
"115792089210356248762697446949407573530086143415290314195533631308867097853951",
)
.unwrap()
});
// `A: -3`
const A: Lazy<BigInt> = Lazy::new(|| BigInt::from(-3));
// `B: 0x5ac635d8aa3a93e7b3ebbd55769886bc651d06b0cc53b0f63bce3c3e27d2604b`
const B: Lazy<BigInt> = Lazy::new(|| {
BigInt::parse_bytes(
b"5ac635d8aa3a93e7b3ebbd55769886bc651d06b0cc53b0f63bce3c3e27d2604b",
16,
)
.unwrap()
});
// `Z: -10`
const Z: Lazy<BigInt> = Lazy::new(|| BigInt::from(-10));
// https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-hash-to-curve-11#section-3
// `hash_to_curve` calls `hash_to_field` with a `count` of `2`
// https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-hash-to-curve-11#section-5.3
// `hash_to_field` calls `expand_message` with a `len_in_bytes` of `count * L`
let uniform_bytes = super::expand::expand_message_xmd::<H>(msg, dst, 2 * L)?;
// map to curve
let (q0x, q0y) = map_to_curve_simple_swu(&uniform_bytes[..L], &A, &B, &P, &Z);
let (q1x, q1y) = map_to_curve_simple_swu(&uniform_bytes[L..], &A, &B, &P, &Z);
// convert to `p256` types
let p0 = AffinePoint::from_encoded_point(&EncodedPoint::from_affine_coordinates(
&q0x, &q0y, false,
))
.ok_or(InternalError::PointError)?
.to_curve();
let p1 = AffinePoint::from_encoded_point(&EncodedPoint::from_affine_coordinates(
&q1x, &q1y, false,
))
.ok_or(InternalError::PointError)?;
Ok(p0 + p1)
}
// Implements the `HashToScalar()` function from
// https://www.ietf.org/archive/id/draft-irtf-cfrg-voprf-07.html#section-4.3
fn hash_to_scalar<H: Hash>(input: &[u8], dst: &[u8]) -> Result<Self::Scalar, ProtocolError> {
// https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf#[{%22num%22:211,%22gen%22:0},{%22name%22:%22XYZ%22},70,700,0]
// P-256 `n` is defined as `115792089210356248762697446949407573529996955224135760342 422259061068512044369`
const N: once_cell::unsync::Lazy<BigInt> = once_cell::unsync::Lazy::new(|| {
BigInt::from_str(
"115792089210356248762697446949407573529996955224135760342422259061068512044369",
)
.unwrap()
});
// https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-hash-to-curve-11#section-5.3
// `HashToScalar` is `hash_to_field`
let uniform_bytes = super::expand::expand_message_xmd::<H>(input, dst, L)?;
let mut bytes = BigInt::from_bytes_be(Sign::Plus, &uniform_bytes)
.mod_floor(&N)
.to_bytes_be()
.1;
bytes.resize(32, 0);
Ok(p256_::Scalar::from_bytes_reduced(GenericArray::from_slice(
&bytes,
)))
}
type ElemLen = U33;
type Scalar = p256_::Scalar;
type ScalarLen = U32;
fn from_scalar_slice(
scalar_bits: &GenericArray<u8, Self::ScalarLen>,
) -> Result<Self::Scalar, InternalError> {
Ok(Self::Scalar::from_bytes_reduced(scalar_bits))
}
fn random_nonzero_scalar<R: RngCore + CryptoRng>(rng: &mut R) -> Self::Scalar {
Self::Scalar::random(rng)
}
fn scalar_as_bytes(scalar: Self::Scalar) -> GenericArray<u8, Self::ScalarLen> {
scalar.into()
}
fn scalar_invert(scalar: &Self::Scalar) -> Self::Scalar {
scalar.invert().unwrap_or(Self::Scalar::zero())
}
fn from_element_slice(
element_bits: &GenericArray<u8, Self::ElemLen>,
) -> Result<Self, InternalError> {
Option::from(Self::from_bytes(element_bits)).ok_or(InternalError::PointError)
}
fn to_arr(&self) -> GenericArray<u8, Self::ElemLen> {
let mut bytes = self.to_affine().to_encoded_point(true).as_bytes().to_vec();
bytes.resize(33, 0);
*GenericArray::from_slice(&bytes)
}
fn base_point() -> Self {
Self::generator()
}
fn mult_by_slice(&self, scalar: &GenericArray<u8, Self::ScalarLen>) -> Self {
self * &Self::Scalar::from_bytes_reduced(scalar)
}
fn is_identity(&self) -> bool {
self == &Self::identity()
}
fn ct_equal(&self, other: &Self) -> bool {
self.ct_eq(other).into()
}
}
/// Corresponds to the map_to_curve_simple_swu() function defined in
/// <https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-hash-to-curve-11#appendix-F.2>
#[allow(clippy::many_single_char_names)]
fn map_to_curve_simple_swu<N: ArrayLength<u8>>(
u: &[u8],
a: &BigInt,
b: &BigInt,
p: &BigInt,
z: &BigInt,
) -> (GenericArray<u8, N>, GenericArray<u8, N>) {
#[derive(Clone)]
struct Field<'a>(&'a BigInt);
impl<'a> Field<'a> {
fn new(p: &'a BigInt) -> Self {
Self(p)
}
fn element(&'a self, number: &BigInt) -> FieldElement<'a> {
FieldElement {
number: number.mod_floor(self.0),
f: self,
}
}
fn one(&'a self) -> FieldElement<'a> {
self.element(&BigInt::one())
}
/// See <https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-hash-to-curve-11#section-4>
fn inv0(&'a self, number: &FieldElement<'a>) -> FieldElement<'a> {
number.pow_internal(&(self.0 - 2))
}
}
/// Finite field arithmetic
#[derive(Clone)]
struct FieldElement<'a> {
number: BigInt,
f: &'a Field<'a>,
}
impl<'a> Add for FieldElement<'a> {
type Output = FieldElement<'a>;
fn add(self, rhs: Self) -> Self::Output {
&self + &rhs
}
}
impl<'a> Add for &FieldElement<'a> {
type Output = FieldElement<'a>;
fn add(self, rhs: Self) -> Self::Output {
self.f.element(&(&self.number + &rhs.number))
}
}
impl<'a> Sub for &FieldElement<'a> {
type Output = FieldElement<'a>;
fn sub(self, rhs: Self) -> Self::Output {
self.f.element(&(&self.number - &rhs.number))
}
}
impl<'a> Neg for FieldElement<'a> {
type Output = FieldElement<'a>;
fn neg(self) -> Self::Output {
-&self
}
}
impl<'a> Neg for &FieldElement<'a> {
type Output = FieldElement<'a>;
fn neg(self) -> Self::Output {
self.f.element(&-&self.number)
}
}
impl<'a> Mul for FieldElement<'a> {
type Output = FieldElement<'a>;
fn mul(self, rhs: Self) -> Self::Output {
&self * &rhs
}
}
impl<'a> Mul<&Self> for FieldElement<'a> {
type Output = FieldElement<'a>;
fn mul(self, rhs: &Self) -> Self::Output {
&self * rhs
}
}
impl<'a> Mul<FieldElement<'a>> for &FieldElement<'a> {
type Output = FieldElement<'a>;
fn mul(self, rhs: FieldElement<'a>) -> Self::Output {
self * &rhs
}
}
impl<'a> Mul for &FieldElement<'a> {
type Output = FieldElement<'a>;
fn mul(self, rhs: Self) -> Self::Output {
self.f.element(&(&self.number * &rhs.number))
}
}
impl<'a> Div<&Self> for FieldElement<'a> {
type Output = FieldElement<'a>;
#[allow(clippy::suspicious_arithmetic_impl)]
fn div(self, rhs: &Self) -> Self::Output {
self * rhs.f.inv0(rhs)
}
}
impl<'a> FieldElement<'a> {
fn square(&self) -> Self {
self * self
}
fn pow_internal(&self, exponent: &BigInt) -> Self {
let exponent = exponent.mod_floor(&(self.f.0 - 1));
self.f.element(&self.number.modpow(&exponent, self.f.0))
}
/// Corresponds to the sqrt_3mod4() function defined in
/// <https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-hash-to-curve-11#appendix-I.1>
fn sqrt(&self) -> Self {
// constant
let c1 = (self.f.0 + 1) >> 2;
self.pow_internal(&c1)
}
/// Corresponds to the sgn0_m_eq_1() function defined in
/// <https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-hash-to-curve-11#section-4.1>
fn sgn0(&self) -> i32 {
(&self.number % 2_usize).to_i32().unwrap()
}
fn is_zero(&self) -> bool {
self.number.is_one()
}
/// Corresponds to the is_square() function defined in
/// <https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-hash-to-curve-11#section-4>
fn is_square(&self) -> bool {
// constant
let exponent = (self.f.0 - 1) >> 1;
let result = self.pow_internal(&exponent);
result.number.is_one() || result.is_zero()
}
fn to_bytes<N: ArrayLength<u8>>(&self) -> GenericArray<u8, N> {
GenericArray::clone_from_slice(&self.number.mod_floor(self.f.0).to_bytes_be().1)
}
}
fn cmov<'a>(x: &FieldElement<'a>, y: &FieldElement<'a>, b: bool) -> FieldElement<'a> {
if b {
y.clone()
} else {
x.clone()
}
}
let f = Field::new(p);
let a = f.element(a);
let b = f.element(b);
let z = f.element(z);
let u = f.element(&BigInt::from_bytes_be(Sign::Plus, u));
// Constants:
// 1. c1 = -B / A
let c1 = -&b / &a;
// 2. c2 = -1 / Z
let c2 = -f.one() / &z;
// Steps:
// 1. tv1 = Z * u^2
let tv1 = z * u.square();
// 2. tv2 = tv1^2
let mut tv2 = tv1.square();
// 3. x1 = tv1 + tv2
let mut x1 = &tv1 + &tv2;
// 4. x1 = inv0(x1)
x1 = f.inv0(&x1);
// 5. e1 = x1 == 0
let e1 = x1.is_zero();
// 6. x1 = x1 + 1
x1 = x1 + f.one();
// 7. x1 = CMOV(x1, c2, e1) # If (tv1 + tv2) == 0, set x1 = -1 / Z
x1 = cmov(&x1, &c2, e1);
// 8. x1 = x1 * c1 # x1 = (-B / A) * (1 + (1 / (Z^2 * u^4 + Z * u^2)))
x1 = x1 * c1;
// 9. gx1 = x1^2
let mut gx1 = x1.square();
// 10. gx1 = gx1 + A
gx1 = gx1 + a;
// 11. gx1 = gx1 * x1
gx1 = gx1 * &x1;
// 12. gx1 = gx1 + B # gx1 = g(x1) = x1^3 + A * x1 + B
gx1 = gx1 + b;
// 13. x2 = tv1 * x1 # x2 = Z * u^2 * x1
let x2 = &tv1 * &x1;
// 14. tv2 = tv1 * tv2
tv2 = tv1 * tv2;
// 15. gx2 = gx1 * tv2 # gx2 = (Z * u^2)^3 * gx1
let gx2 = &gx1 * tv2;
// 16. e2 = is_square(gx1)
let e2 = gx1.is_square();
// 17. x = CMOV(x2, x1, e2) # If is_square(gx1), x = x1, else x = x2
let x = cmov(&x2, &x1, e2);
// 18. y2 = CMOV(gx2, gx1, e2) # If is_square(gx1), y2 = gx1, else y2 = gx2
let y2 = cmov(&gx2, &gx1, e2);
// 19. y = sqrt(y2)
let mut y = y2.sqrt();
// 20. e3 = sgn0(u) == sgn0(y) # Fix sign of y
let e3 = u.sgn0() == y.sgn0();
// 21. y = CMOV(-y, y, e3)
y = cmov(&-&y, &y, e3);
// 22. return (x, y)
(x.to_bytes(), y.to_bytes())
}
#[cfg(test)]
mod tests {
use super::*;
struct Params {
msg: &'static str,
px: &'static str,
py: &'static str,
u0: &'static str,
u1: &'static str,
q0x: &'static str,
q0y: &'static str,
q1x: &'static str,
q1y: &'static str,
}
#[test]
fn map_to_curve_simple_swu() {
const P: Lazy<BigInt> = Lazy::new(|| {
BigInt::from_str(
"115792089210356248762697446949407573530086143415290314195533631308867097853951",
)
.unwrap()
});
const A: Lazy<BigInt> = Lazy::new(|| BigInt::from(-3));
const B: Lazy<BigInt> = Lazy::new(|| {
BigInt::parse_bytes(
b"5ac635d8aa3a93e7b3ebbd55769886bc651d06b0cc53b0f63bce3c3e27d2604b",
16,
)
.unwrap()
});
const Z: Lazy<BigInt> = Lazy::new(|| BigInt::from(-10));
// Test vectors taken from https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-hash-to-curve-11#appendix-J.1.1
let test_vectors = alloc::vec![
Params {
msg: "",
px: "2c15230b26dbc6fc9a37051158c95b79656e17a1a920b11394ca91c44247d3e4",
py: "8a7a74985cc5c776cdfe4b1f19884970453912e9d31528c060be9ab5c43e8415",
u0: "ad5342c66a6dd0ff080df1da0ea1c04b96e0330dd89406465eeba11582515009",
u1: "8c0f1d43204bd6f6ea70ae8013070a1518b43873bcd850aafa0a9e220e2eea5a",
q0x: "ab640a12220d3ff283510ff3f4b1953d09fad35795140b1c5d64f313967934d5",
q0y: "dccb558863804a881d4fff3455716c836cef230e5209594ddd33d85c565b19b1",
q1x: "51cce63c50d972a6e51c61334f0f4875c9ac1cd2d3238412f84e31da7d980ef5",
q1y: "b45d1a36d00ad90e5ec7840a60a4de411917fbe7c82c3949a6e699e5a1b66aac",
},
Params {
msg: "abc",
px: "0bb8b87485551aa43ed54f009230450b492fead5f1cc91658775dac4a3388a0f",
py: "5c41b3d0731a27a7b14bc0bf0ccded2d8751f83493404c84a88e71ffd424212e",
u0: "afe47f2ea2b10465cc26ac403194dfb68b7f5ee865cda61e9f3e07a537220af1",
u1: "379a27833b0bfe6f7bdca08e1e83c760bf9a338ab335542704edcd69ce9e46e0",
q0x: "5219ad0ddef3cc49b714145e91b2f7de6ce0a7a7dc7406c7726c7e373c58cb48",
q0y: "7950144e52d30acbec7b624c203b1996c99617d0b61c2442354301b191d93ecf",
q1x: "019b7cb4efcfeaf39f738fe638e31d375ad6837f58a852d032ff60c69ee3875f",
q1y: "589a62d2b22357fed5449bc38065b760095ebe6aeac84b01156ee4252715446e",
},
Params {
msg: "abcdef0123456789",
px: "65038ac8f2b1def042a5df0b33b1f4eca6bff7cb0f9c6c1526811864e544ed80",
py: "cad44d40a656e7aff4002a8de287abc8ae0482b5ae825822bb870d6df9b56ca3",
u0: "0fad9d125a9477d55cf9357105b0eb3a5c4259809bf87180aa01d651f53d312c",
u1: "b68597377392cd3419d8fcc7d7660948c8403b19ea78bbca4b133c9d2196c0fb",
q0x: "a17bdf2965eb88074bc01157e644ed409dac97cfcf0c61c998ed0fa45e79e4a2",
q0y: "4f1bc80c70d411a3cc1d67aeae6e726f0f311639fee560c7f5a664554e3c9c2e",
q1x: "7da48bb67225c1a17d452c983798113f47e438e4202219dd0715f8419b274d66",
q1y: "b765696b2913e36db3016c47edb99e24b1da30e761a8a3215dc0ec4d8f96e6f9",
},
Params {
msg: "q128_qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq\
qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq\
qqqqqqqqqqqqqqqqqqqqqqqqq",
px: "4be61ee205094282ba8a2042bcb48d88dfbb609301c49aa8b078533dc65a0b5d",
py: "98f8df449a072c4721d241a3b1236d3caccba603f916ca680f4539d2bfb3c29e",
u0: "3bbc30446f39a7befad080f4d5f32ed116b9534626993d2cc5033f6f8d805919",
u1: "76bb02db019ca9d3c1e02f0c17f8baf617bbdae5c393a81d9ce11e3be1bf1d33",
q0x: "c76aaa823aeadeb3f356909cb08f97eee46ecb157c1f56699b5efebddf0e6398",
q0y: "776a6f45f528a0e8d289a4be12c4fab80762386ec644abf2bffb9b627e4352b1",
q1x: "418ac3d85a5ccc4ea8dec14f750a3a9ec8b85176c95a7022f391826794eb5a75",
q1y: "fd6604f69e9d9d2b74b072d14ea13050db72c932815523305cb9e807cc900aff",
},
Params {
msg: "a512_aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
px: "457ae2981f70ca85d8e24c308b14db22f3e3862c5ea0f652ca38b5e49cd64bc5",
py: "ecb9f0eadc9aeed232dabc53235368c1394c78de05dd96893eefa62b0f4757dc",
u0: "4ebc95a6e839b1ae3c63b847798e85cb3c12d3817ec6ebc10af6ee51adb29fec",
u1: "4e21af88e22ea80156aff790750121035b3eefaa96b425a8716e0d20b4e269ee",
q0x: "d88b989ee9d1295df413d4456c5c850b8b2fb0f5402cc5c4c7e815412e926db8",
q0y: "bb4a1edeff506cf16def96afff41b16fc74f6dbd55c2210e5b8f011ba32f4f40",
q1x: "a281e34e628f3a4d2a53fa87ff973537d68ad4fbc28d3be5e8d9f6a2571c5a4b",
q1y: "f6ed88a7aab56a488100e6f1174fa9810b47db13e86be999644922961206e184",
},
];
let dst = "QUUX-V01-CS02-with-P256_XMD:SHA-256_SSWU_RO_";
for tv in test_vectors {
let uniform_bytes = super::super::expand::expand_message_xmd::<sha2::Sha256>(
tv.msg.as_bytes(),
dst.as_bytes(),
96,
)
.unwrap();
let u0 = BigInt::from_bytes_be(Sign::Plus, &uniform_bytes[..48]).mod_floor(&P);
let u1 = BigInt::from_bytes_be(Sign::Plus, &uniform_bytes[48..]).mod_floor(&P);
assert_eq!(BigInt::parse_bytes(tv.u0.as_bytes(), 16).unwrap(), u0);
assert_eq!(BigInt::parse_bytes(tv.u1.as_bytes(), 16).unwrap(), u1);
let (q0x, q0y) = super::map_to_curve_simple_swu(&u0.to_bytes_be().1, &A, &B, &P, &Z);
let (q1x, q1y) = super::map_to_curve_simple_swu(&u1.to_bytes_be().1, &A, &B, &P, &Z);
assert_eq!(tv.q0x, hex::encode(q0x));
assert_eq!(tv.q0y, hex::encode(q0y));
assert_eq!(tv.q1x, hex::encode(q1x));
assert_eq!(tv.q1y, hex::encode(q1y));
let p0 = AffinePoint::from_encoded_point(&EncodedPoint::from_affine_coordinates(
&q0x, &q0y, false,
))
.unwrap()
.to_curve();
let p1 = AffinePoint::from_encoded_point(&EncodedPoint::from_affine_coordinates(
&q1x, &q1y, false,
))
.unwrap();
let p = (p0 + p1).to_encoded_point(false);
assert_eq!(tv.px, hex::encode(p.x().unwrap()));
assert_eq!(tv.py, hex::encode(p.y().unwrap()));
}
}
}
src/group/ristretto.rs
+118
View File
@@ -0,0 +1,118 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
use super::Group;
use crate::errors::InternalError;
use crate::hash::Hash;
use core::convert::TryInto;
use curve25519_dalek::{
constants::RISTRETTO_BASEPOINT_POINT,
ristretto::{CompressedRistretto, RistrettoPoint},
scalar::Scalar,
traits::Identity,
};
use generic_array::{typenum::U32, GenericArray};
use rand::{CryptoRng, RngCore};
use subtle::ConstantTimeEq;
/// The implementation of such a subgroup for Ristretto
impl Group for RistrettoPoint {
const SUITE_ID: usize = 0x0001;
// Implements the `hash_to_ristretto255()` function from
// https://www.ietf.org/archive/id/draft-irtf-cfrg-hash-to-curve-10.txt
fn map_to_curve<H: Hash>(msg: &[u8], dst: &[u8]) -> Result<Self, InternalError> {
let uniform_bytes = super::expand::expand_message_xmd::<H>(msg, dst, 64)?;
Ok(RistrettoPoint::from_uniform_bytes(
uniform_bytes
.as_slice()
.try_into()
.map_err(|_| InternalError::HashToCurveError)?,
))
}
// Implements the `HashToScalar()` function from
// https://www.ietf.org/archive/id/draft-irtf-cfrg-voprf-07.html#section-4.1
fn hash_to_scalar<H: Hash>(input: &[u8], dst: &[u8]) -> Result<Self::Scalar, InternalError> {
let uniform_bytes = super::expand::expand_message_xmd::<H>(input, dst, 64)?;
Ok(Scalar::from_bytes_mod_order_wide(
uniform_bytes
.as_slice()
.try_into()
.map_err(|_| InternalError::HashToCurveError)?,
))
}
type Scalar = Scalar;
type ScalarLen = U32;
fn from_scalar_slice(
scalar_bits: &GenericArray<u8, Self::ScalarLen>,
) -> Result<Self::Scalar, InternalError> {
Ok(Scalar::from_bytes_mod_order(*scalar_bits.as_ref()))
}
fn random_nonzero_scalar<R: RngCore + CryptoRng>(rng: &mut R) -> Self::Scalar {
loop {
let scalar = {
#[cfg(not(test))]
{
let mut scalar_bytes = [0u8; 64];
rng.fill_bytes(&mut scalar_bytes);
Scalar::from_bytes_mod_order_wide(&scalar_bytes)
}
// Tests need an exact conversion from bytes to scalar, sampling only 32 bytes from rng
#[cfg(test)]
{
let mut scalar_bytes = [0u8; 32];
rng.fill_bytes(&mut scalar_bytes);
Scalar::from_bytes_mod_order(scalar_bytes)
}
};
if scalar != Scalar::zero() {
break scalar;
}
}
}
fn scalar_as_bytes(scalar: Self::Scalar) -> GenericArray<u8, Self::ScalarLen> {
scalar.to_bytes().into()
}
fn scalar_invert(scalar: &Self::Scalar) -> Self::Scalar {
scalar.invert()
}
// The byte length necessary to represent group elements
type ElemLen = U32;
fn from_element_slice(
element_bits: &GenericArray<u8, Self::ElemLen>,
) -> Result<Self, InternalError> {
CompressedRistretto::from_slice(element_bits)
.decompress()
.ok_or(InternalError::PointError)
}
// serialization of a group element
fn to_arr(&self) -> GenericArray<u8, Self::ElemLen> {
self.compress().to_bytes().into()
}
fn base_point() -> Self {
RISTRETTO_BASEPOINT_POINT
}
fn mult_by_slice(&self, scalar: &GenericArray<u8, Self::ScalarLen>) -> Self {
self * Scalar::from_bits(*scalar.as_ref())
}
/// Returns if the group element is equal to the identity (1)
fn is_identity(&self) -> bool {
self == &Self::identity()
}
fn ct_equal(&self, other: &Self) -> bool {
ConstantTimeEq::ct_eq(self, other).into()
}
}
src/group/x25519.rs
+91
View File
@@ -0,0 +1,91 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
use super::Group;
use crate::errors::InternalError;
use crate::hash::Hash;
use curve25519_dalek::{constants::X25519_BASEPOINT, montgomery::MontgomeryPoint, scalar::Scalar};
use generic_array::{typenum::U32, GenericArray};
use rand::{CryptoRng, RngCore};
/// The implementation of such a subgroup for Ristretto
impl Group for MontgomeryPoint {
const SUITE_ID: usize = 0xFFFF;
fn map_to_curve<H: Hash>(_msg: &[u8], _dst: &[u8]) -> Result<Self, InternalError> {
unreachable!("this algorithm should only be used as the `KeGroup`")
}
fn hash_to_scalar<H: Hash>(_input: &[u8], _dst: &[u8]) -> Result<Self::Scalar, InternalError> {
unreachable!("this algorithm should only be used as the `KeGroup`")
}
type Scalar = Scalar;
type ScalarLen = U32;
fn from_scalar_slice(
scalar_bits: &GenericArray<u8, Self::ScalarLen>,
) -> Result<Self::Scalar, InternalError> {
Ok(Scalar::from_bytes_mod_order(*scalar_bits.as_ref()))
}
fn random_nonzero_scalar<R: RngCore + CryptoRng>(rng: &mut R) -> Self::Scalar {
loop {
let scalar = {
#[cfg(not(test))]
{
let mut scalar_bytes = [0u8; 64];
rng.fill_bytes(&mut scalar_bytes);
Scalar::from_bytes_mod_order_wide(&scalar_bytes)
}
// Tests need an exact conversion from bytes to scalar, sampling only 32 bytes from rng
#[cfg(test)]
{
let mut scalar_bytes = [0u8; 32];
rng.fill_bytes(&mut scalar_bytes);
Scalar::from_bytes_mod_order(scalar_bytes)
}
};
if scalar != Scalar::zero() {
break scalar;
}
}
}
fn scalar_as_bytes(scalar: Self::Scalar) -> GenericArray<u8, Self::ScalarLen> {
scalar.to_bytes().into()
}
fn scalar_invert(_scalar: &Self::Scalar) -> Self::Scalar {
unreachable!("this algorithm should only be used as the `KeGroup`")
}
// The byte length necessary to represent group elements
type ElemLen = U32;
fn from_element_slice(
element_bits: &GenericArray<u8, Self::ElemLen>,
) -> Result<Self, InternalError> {
Ok(Self(*element_bits.as_ref()))
}
// serialization of a group element
fn to_arr(&self) -> GenericArray<u8, Self::ElemLen> {
self.to_bytes().into()
}
fn base_point() -> Self {
X25519_BASEPOINT
}
fn mult_by_slice(&self, scalar: &GenericArray<u8, Self::ScalarLen>) -> Self {
self * Scalar::from_bits(*scalar.as_ref())
}
/// Returns if the group element is equal to the identity (1)
fn is_identity(&self) -> bool {
unreachable!("this algorithm should only be used as the `KeGroup`")
}
fn ct_equal(&self, _other: &Self) -> bool {
unreachable!("this algorithm should only be used as the `KeGroup`")
}
}
src/hash.rs
+15
View File
@@ -0,0 +1,15 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
//! A convenience trait for digest bounds used throughout the library
use digest::{BlockInput, FixedOutput, Reset, Update};
/// Trait inheriting the requirements from digest::Digest for compatibility with HKDF and HMAC
// Associated types could be simplified when they are made as defaults:
// https://github.com/rust-lang/rust/issues/29661
pub trait Hash: Update + BlockInput + FixedOutput + Reset + Default + Clone {}
impl<T: Update + BlockInput + FixedOutput + Reset + Default + Clone> Hash for T {}
src/lib.rs
+22
View File
@@ -0,0 +1,22 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
// #![cfg_attr(not(feature = "bench"), deny(missing_docs))]
#![deny(unsafe_code)]
#![cfg_attr(not(feature = "std"), no_std)]
extern crate alloc;
#[macro_use]
mod serialization;
pub mod ciphersuite;
pub mod errors;
pub mod group;
pub mod hash;
pub mod voprf;
#[cfg(test)]
mod tests;
src/serialization.rs
+52
View File
@@ -0,0 +1,52 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
use crate::errors::InternalError;
use alloc::vec::Vec;
// Corresponds to the I2OSP() function from RFC8017
pub(crate) fn i2osp(input: usize, length: usize) -> Result<alloc::vec::Vec<u8>, InternalError> {
let sizeof_usize = core::mem::size_of::<usize>();
// Check if input >= 256^length
if (sizeof_usize as u32 - input.leading_zeros() / 8) > length as u32 {
return Err(InternalError::SerializationError);
}
if length <= sizeof_usize {
return Ok((&input.to_be_bytes()[sizeof_usize - length..]).to_vec());
}
let mut output = alloc::vec![0u8; length];
output.splice(
length - sizeof_usize..length,
input.to_be_bytes().iter().cloned(),
);
Ok(output)
}
// Computes I2OSP(len(input), max_bytes) || input
pub(crate) fn serialize(input: &[u8], max_bytes: usize) -> Result<Vec<u8>, InternalError> {
Ok([&i2osp(input.len(), max_bytes)?, input].concat())
}
#[cfg(test)]
mod unit_tests {
use super::*;
// Test the error condition for I2OSP
#[test]
fn test_i2osp_err_check() {
assert!(i2osp(0, 1).is_ok());
assert!(i2osp(255, 1).is_ok());
assert!(i2osp(256, 1).is_err());
assert!(i2osp(257, 1).is_err());
assert!(i2osp(256 * 256 - 1, 2).is_ok());
assert!(i2osp(256 * 256, 2).is_err());
assert!(i2osp(256 * 256 + 1, 2).is_err());
}
}
src/tests/mock_rng.rs
+64
View File
@@ -0,0 +1,64 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
use alloc::vec::Vec;
use core::cmp::min;
use rand::{CryptoRng, Error, RngCore};
/// A simple implementation of `RngCore` for testing purposes.
///
/// This generates a cyclic sequence (i.e. cycles over an initial buffer)
///
///
#[derive(Debug, Clone)]
pub struct CycleRng {
v: Vec<u8>,
}
impl CycleRng {
/// Create a `CycleRng`, yielding a sequence starting with
/// `initial` and looping thereafter
pub fn new(initial: Vec<u8>) -> Self {
CycleRng { v: initial }
}
}
fn rotate_left<T>(data: &mut [T], steps: usize) {
if data.is_empty() {
return;
}
let steps = steps % data.len();
data[..steps].reverse();
data[steps..].reverse();
data.reverse();
}
impl RngCore for CycleRng {
fn next_u32(&mut self) -> u32 {
unimplemented!()
}
#[inline]
fn next_u64(&mut self) -> u64 {
unimplemented!()
}
#[inline]
fn fill_bytes(&mut self, dest: &mut [u8]) {
let len = min(self.v.len(), dest.len());
(&mut dest[..len]).copy_from_slice(&self.v[..len]);
rotate_left(&mut self.v, len);
}
#[inline]
fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
self.fill_bytes(dest);
Ok(())
}
}
// This is meant for testing only
impl CryptoRng for CycleRng {}
src/tests/mod.rs
+7
View File
@@ -0,0 +1,7 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
mod mock_rng;
mod voprf_test_vectors;
src/tests/voprf_test_vectors.rs
+176
View File
@@ -0,0 +1,176 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
use crate::ciphersuite::CipherSuite;
use crate::errors::*;
use crate::group::Group;
use crate::tests::mock_rng::CycleRng;
use crate::voprf::{Client, Server};
use alloc::string::ToString;
use alloc::vec::Vec;
use curve25519_dalek::ristretto::RistrettoPoint;
use generic_array::GenericArray;
use serde_json::Value;
use sha2::Sha512;
struct VOPRFTestVectorParameters {
sksm: Vec<u8>,
input: Vec<u8>,
blind: Vec<u8>,
blinded_element: Vec<u8>,
evaluation_element: Vec<u8>,
output: Vec<u8>,
}
// Taken from https://github.com/cfrg/draft-irtf-cfrg-voprf/blob/master/draft-irtf-cfrg-voprf.md
// in base mode
static OPRF_RISTRETTO255_SHA512: &[&str] = &[
r#"
{
"sksm": "caeff69352df4905a9121a4997704ca8cee1524a110819eb87deba1a39ec1701",
"input": "00",
"blind": "c604c785ada70d77a5256ae21767de8c3304115237d262134f5e46e512cf8e03",
"blinded_element": "fc20e03aff3a9de9b37e8d35886ade11ec7d85c2a1fb5bb0b1686c64e07ac467",
"evaluation_element": "7c72cc293cd7d44c0b57c273f27befd598b132edc665694bdc9c42a4d3083c0a",
"output": "e3a209dce2d3ea3d84fcddb282818caebb756a341e08a310d9904314f5392085d13c3f76339d745db0f46974a6049c3ea9546305af55d37760b2136d9b3f0134"
}
"#,
r#"
{
"sksm": "caeff69352df4905a9121a4997704ca8cee1524a110819eb87deba1a39ec1701",
"input": "5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a",
"blind": "5ed895206bfc53316d307b23e46ecc6623afb3086da74189a416012be037e50b",
"blinded_element": "483d4f39de5ff77fa0f9a0ad2334dd5bf87f2cda868539d21de67ce49e7d1536",
"evaluation_element": "026f2758fc62f02a7ff95f35ec6f20186aa57c0274361655543ea235d7b2aa34",
"output": "2c17dc3e9398dadb44bb2d3360c446302e99f1fe0ec40f0b1ad25c9cf002be1e4b41b4900ef056537fe8c14532ccea4d796f5feab9541af48057d83c0db86fe9"
}
"#,
];
#[cfg(feature = "p256")]
static OPRF_P256_SHA256: &[&str] = &[
r#"
{
"sksm": "a1b2355828f2c76de6749af9d093bd9fe0f2cada3ec653cd9a6d3126a7a7827b",
"input": "00",
"blind": "5d9e7f6efd3093c32ecceabd57fb03cf760c926d2a7bfa265babf29ec98af0d0",
"blinded_element": "03e3c379698da853d9844098fa0ac676970d5ec24167b598714cd2ee188604ddd2",
"evaluation_element": "03ea54e8d095332d1a601a3f8a5013188aea036bf9b563236f7fd3b046908b42fd",
"output": "464e3e51e4086a824d9a2f939524d7069ae4072a788bc9d5daa0762b25826437"
}
"#,
r#"
{
"sksm": "a1b2355828f2c76de6749af9d093bd9fe0f2cada3ec653cd9a6d3126a7a7827b",
"input": "5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a",
"blind": "825155ab61f17605af2ae2e935c78d857c9407bcd45128d57d338f1671b5fcbe",
"blinded_element": "030b40be181ffbb3c3ae4a4911287c43261f5e4034781def69c51608f372a02102",
"evaluation_element": "03115ad70ea55dbb4006da0ee3589a3582f31ef9cd143996d1e31a25ad3abdcf6f",
"output": "b597d58c843d0f9d2712121b0a3e2912ebee1c829eed3089eade9af4359ab275"
}
"#,
];
fn decode(values: &Value, key: &str) -> Option<Vec<u8>> {
values[key]
.as_str()
.and_then(|s| hex::decode(&s.to_string()).ok())
}
fn populate_test_vectors(values: &Value) -> VOPRFTestVectorParameters {
VOPRFTestVectorParameters {
sksm: decode(&values, "sksm").unwrap(),
input: decode(&values, "input").unwrap(),
blind: decode(&values, "blind").unwrap(),
blinded_element: decode(&values, "blinded_element").unwrap(),
evaluation_element: decode(&values, "evaluation_element").unwrap(),
output: decode(&values, "output").unwrap(),
}
}
struct Ristretto255Sha512;
impl CipherSuite for Ristretto255Sha512 {
type Group = RistrettoPoint;
type Hash = Sha512;
}
#[test]
fn tests() -> Result<(), InternalError> {
test_blind::<Ristretto255Sha512>(OPRF_RISTRETTO255_SHA512)?;
test_evaluate::<Ristretto255Sha512>(OPRF_RISTRETTO255_SHA512)?;
test_finalize::<Ristretto255Sha512>(OPRF_RISTRETTO255_SHA512)?;
#[cfg(feature = "p256")]
{
use p256_::ProjectivePoint;
use sha2::Sha256;
test_blind::<ProjectivePoint, Sha256>(OPRF_P256_SHA256)?;
test_evaluate::<ProjectivePoint>(OPRF_P256_SHA256)?;
test_finalize::<ProjectivePoint, Sha256>(OPRF_P256_SHA256)?;
}
Ok(())
}
// Tests input -> blind, blinded_element
fn test_blind<CS: CipherSuite>(tvs: &[&str]) -> Result<(), InternalError> {
for tv in tvs {
let parameters = populate_test_vectors(&serde_json::from_str(tv).unwrap());
let mut rng = CycleRng::new(parameters.blind.to_vec());
let (client, blinded_element) = Client::<CS>::blind(&parameters.input, &mut rng)?;
assert_eq!(
&parameters.blind,
&CS::Group::scalar_as_bytes(client.get_blind()).to_vec()
);
assert_eq!(
&parameters.blinded_element,
&blinded_element.to_arr().to_vec()
);
}
Ok(())
}
// Tests sksm, blinded_element -> evaluation_element
fn test_evaluate<CS: CipherSuite>(tvs: &[&str]) -> Result<(), InternalError> {
for tv in tvs {
let parameters = populate_test_vectors(&serde_json::from_str(tv).unwrap());
let server = Server::<CS>::new_with_key(&parameters.sksm).unwrap();
let evaluation_element = server.evaluate(
CS::Group::from_element_slice(GenericArray::from_slice(&parameters.blinded_element))
.unwrap(),
);
assert_eq!(
&parameters.evaluation_element,
&evaluation_element.to_arr().to_vec()
);
}
Ok(())
}
// Tests input, blind, evaluation_element -> output
fn test_finalize<CS: CipherSuite>(tvs: &[&str]) -> Result<(), InternalError> {
for tv in tvs {
let parameters = populate_test_vectors(&serde_json::from_str(tv).unwrap());
let client = Client::<CS>::from_data_and_blind(
&parameters.input,
&<CS::Group as Group>::from_scalar_slice(&GenericArray::clone_from_slice(
&parameters.blind,
))
.unwrap(),
);
let output = client.finalize(<CS::Group as Group>::from_element_slice(
GenericArray::from_slice(&parameters.evaluation_element),
)?)?;
assert_eq!(&parameters.output, &output.to_vec());
}
Ok(())
}
src/voprf.rs
+184
View File
@@ -0,0 +1,184 @@
// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.
use crate::ciphersuite::CipherSuite;
use crate::errors::InternalError;
use crate::group::Group;
use crate::hash::Hash;
use crate::serialization::serialize;
use digest::Digest;
use generic_array::GenericArray;
use rand::{CryptoRng, RngCore};
use alloc::vec;
use generic_array::typenum::Unsigned;
static STR_VOPRF: &[u8] = b"HashToGroup-VOPRF07-";
static STR_VOPRF_FINALIZE: &[u8] = b"Finalize-VOPRF07-";
static MODE_BASE: u8 = 0x00;
pub struct Client<CS: CipherSuite> {
data: alloc::vec::Vec<u8>,
blind: <CS::Group as Group>::Scalar,
}
impl<CS: CipherSuite> Client<CS> {
/// Computes the first step for the multiplicative blinding version of DH-OPRF.
pub fn blind<R: RngCore + CryptoRng>(
input: &[u8],
blinding_factor_rng: &mut R,
) -> Result<(Self, CS::Group), InternalError> {
// Choose a random scalar that must be non-zero
let blind = <CS::Group as Group>::random_nonzero_scalar(blinding_factor_rng);
let dst = [
STR_VOPRF,
&<CS::Group as Group>::get_context_string(MODE_BASE)?,
]
.concat();
let mapped_point = <CS::Group as Group>::map_to_curve::<CS::Hash>(input, &dst)?;
let blind_token = mapped_point * &blind;
Ok((
Self {
data: input.to_vec(),
blind,
},
blind_token,
))
}
/// Computes the third step for the multiplicative blinding version of DH-OPRF, in which
/// the client unblinds the server's message.
pub fn finalize(
&self,
evaluated_element: CS::Group,
) -> Result<GenericArray<u8, <CS::Hash as Digest>::OutputSize>, InternalError> {
let unblinded_element =
evaluated_element * &<CS::Group as Group>::scalar_invert(&self.blind);
finalize_after_unblind::<CS::Group, CS::Hash>(&self.data, unblinded_element)
}
#[cfg(test)]
/// Only used for test functions
pub fn from_data_and_blind(data: &[u8], blind: &<CS::Group as Group>::Scalar) -> Self {
Self {
data: data.to_vec(),
blind: blind.clone(),
}
}
#[cfg(test)]
/// Only used for test functions
pub fn get_blind(&self) -> <CS::Group as Group>::Scalar {
self.blind
}
}
pub struct Server<CS: CipherSuite> {
oprf_key: <CS::Group as Group>::Scalar,
}
impl<CS: CipherSuite> Server<CS> {
pub fn new<R: RngCore + CryptoRng>(rng: &mut R) -> Result<Self, InternalError> {
let mut key = vec![0u8; <CS::Hash as Digest>::OutputSize::USIZE];
rng.fill_bytes(&mut key);
Self::new_with_key(&key)
}
pub fn new_with_key(key: &[u8]) -> Result<Self, InternalError> {
Ok(Self {
oprf_key: CS::Group::from_scalar_slice(&GenericArray::clone_from_slice(key))?,
})
}
/// Computes the second step for the multiplicative blinding version of DH-OPRF. This
/// message is sent from the server (who holds the OPRF key) to the client.
pub fn evaluate(&self, point: CS::Group) -> CS::Group {
point * &self.oprf_key
}
}
fn finalize_after_unblind<G: Group, H: Hash>(
input: &[u8],
unblinded_element: G,
) -> Result<GenericArray<u8, <H as Digest>::OutputSize>, InternalError> {
let finalize_dst = [STR_VOPRF_FINALIZE, &G::get_context_string(MODE_BASE)?].concat();
let hash_input = [
serialize(input, 2)?,
serialize(&unblinded_element.to_arr().to_vec(), 2)?,
serialize(&finalize_dst, 2)?,
]
.concat();
Ok(<H as Digest>::digest(&hash_input))
}
///////////
// Tests //
// ===== //
///////////
#[cfg(test)]
mod tests {
use super::*;
use crate::group::Group;
use curve25519_dalek::ristretto::RistrettoPoint;
use generic_array::{arr, GenericArray};
use rand::rngs::OsRng;
use sha2::Sha512;
struct Ristretto255Sha512;
impl CipherSuite for Ristretto255Sha512 {
type Group = RistrettoPoint;
type Hash = Sha512;
}
fn prf(input: &[u8], oprf_key: &[u8]) -> GenericArray<u8, <Sha512 as Digest>::OutputSize> {
let dst = [
STR_VOPRF,
&RistrettoPoint::get_context_string(MODE_BASE).unwrap(),
]
.concat();
let point = RistrettoPoint::map_to_curve::<Sha512>(input, &dst).unwrap();
let scalar =
RistrettoPoint::from_scalar_slice(GenericArray::from_slice(&oprf_key[..])).unwrap();
let res = point * scalar;
finalize_after_unblind::<RistrettoPoint, sha2::Sha512>(&input, res).unwrap()
}
#[test]
fn oprf_retrieval() {
let input = b"hunter2";
let mut rng = OsRng;
let (client, alpha) = Client::<Ristretto255Sha512>::blind(&input[..], &mut rng).unwrap();
let oprf_key_bytes = arr![
u8; 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 30, 31, 32,
];
let server = Server::<Ristretto255Sha512>::new_with_key(&oprf_key_bytes).unwrap();
let beta = server.evaluate(alpha);
let res = client.finalize(beta).unwrap();
let res2 = prf(&input[..], &oprf_key_bytes);
assert_eq!(res, res2);
}
#[test]
fn oprf_inversion_unsalted() {
let mut rng = OsRng;
let mut input = alloc::vec![0u8; 64];
rng.fill_bytes(&mut input);
let (client, alpha) = Client::<Ristretto255Sha512>::blind(&input, &mut rng).unwrap();
let res = client.finalize(alpha).unwrap();
let dst = [
STR_VOPRF,
&RistrettoPoint::get_context_string(MODE_BASE).unwrap(),
]
.concat();
let point = RistrettoPoint::map_to_curve::<Sha512>(&input, &dst).unwrap();
let res2 = finalize_after_unblind::<RistrettoPoint, sha2::Sha512>(&input, point).unwrap();
assert_eq!(res, res2);
}
}