mldsa_core/
lib.rs

1// Copyright (c) 2026-present Thomas <tom@unebaguette.fr>
2// SPDX-License-Identifier: MIT OR Apache-2.0
3
4pub mod wasm;
5
6mod tests;
7
8use ml_dsa::{
9    EncodedVerifyingKey, Generate, MlDsaParams, Signature, VerifyingKey, signature::Keypair,
10    signature::rand_core::UnwrapErr,
11};
12use zeroize::Zeroize;
13
14pub struct KeyPair<const VK: usize> {
15    pub seed: [u8; 32],
16    pub verifying_key: [u8; VK],
17}
18
19impl<const VK: usize> Drop for KeyPair<VK> {
20    fn drop(&mut self) {
21        self.seed.zeroize();
22    }
23}
24
25pub fn generate_keypair<P, const VK: usize>() -> KeyPair<VK>
26where
27    P: MlDsaParams,
28{
29    let mut rng = UnwrapErr(getrandom::SysRng);
30    let key: ml_dsa::SigningKey<P> = Generate::generate_from_rng(&mut rng);
31
32    let seed: [u8; 32] = key.to_seed().into();
33    let vk = key.verifying_key().encode();
34
35    let mut vk_bytes = [0u8; VK];
36
37    vk_bytes.copy_from_slice(&vk);
38
39    KeyPair {
40        seed,
41        verifying_key: vk_bytes,
42    }
43}
44
45pub fn generate_keypair_from_seed<P, const VK: usize>(seed: &[u8; 32]) -> KeyPair<VK>
46where
47    P: MlDsaParams,
48{
49    let seed_arr = ml_dsa::B32::from(*seed);
50    let sig_key = ml_dsa::SigningKey::<P>::from_seed(&seed_arr);
51
52    let vk = sig_key.verifying_key().encode();
53    let mut vk_bytes = [0u8; VK];
54
55    vk_bytes.copy_from_slice(&vk);
56
57    KeyPair {
58        seed: *seed,
59        verifying_key: vk_bytes,
60    }
61}
62
63pub fn sign<P, const SIG: usize>(
64    seed: &[u8; 32],
65    message: &[u8],
66    context: Option<&[u8]>,
67) -> [u8; SIG]
68where
69    P: MlDsaParams,
70{
71    let ctx = context.unwrap_or(&[]);
72    assert!(ctx.len() <= 255, "context must be at most 255 bytes");
73
74    let seed_arr = ml_dsa::B32::from(*seed);
75    let sig_key = ml_dsa::SigningKey::<P>::from_seed(&seed_arr);
76
77    let esk = sig_key.expanded_key();
78
79    let sig = esk
80        .sign_deterministic(message, ctx)
81        .expect("sign_deterministic failed despite valid context");
82
83    let mut sig_bytes = [0u8; SIG];
84
85    sig_bytes.copy_from_slice(&sig.encode());
86
87    sig_bytes
88}
89
90pub fn verify<P, const VK: usize, const SIG: usize>(
91    vk_bytes: &[u8; VK],
92    message: &[u8],
93    sig_bytes: &[u8; SIG],
94    context: Option<&[u8]>,
95) -> bool
96where
97    P: MlDsaParams,
98{
99    let ctx = context.unwrap_or(&[]);
100
101    let vk_encoded = match EncodedVerifyingKey::<P>::try_from(vk_bytes.as_slice()) {
102        Ok(v) => v,
103        Err(_) => return false,
104    };
105
106    let vk = VerifyingKey::<P>::decode(&vk_encoded);
107
108    let sig = match Signature::<P>::try_from(sig_bytes.as_slice()) {
109        Ok(s) => s,
110        Err(_) => return false,
111    };
112
113    vk.verify_with_context(message, ctx, &sig)
114}
115
116#[macro_export]
117macro_rules! impl_mldsa_variant {
118    ($variant:ident, $seed:expr, $sk:expr, $vk:expr, $sig:expr) => {
119        use ml_dsa::$variant;
120        use mldsa_core::KeyPair as CoreKeyPair;
121
122        #[cfg(all(
123            not(target_feature = "atomics"),
124            target_family = "wasm",
125            feature = "talc"
126        ))]
127        #[global_allocator]
128        static TALC: talc::wasm::WasmDynamicTalc = talc::wasm::new_wasm_dynamic_allocator();
129
130        pub const SEED_SIZE: usize = $seed;
131        pub const SIGNING_KEY_SIZE: usize = $sk;
132        pub const VERIFYING_KEY_SIZE: usize = $vk;
133        pub const SIGNATURE_SIZE: usize = $sig;
134
135        pub type KeyPair = CoreKeyPair<VERIFYING_KEY_SIZE>;
136
137        pub fn generate_keypair() -> KeyPair {
138            mldsa_core::generate_keypair::<$variant, VERIFYING_KEY_SIZE>()
139        }
140
141        pub fn generate_keypair_from_seed(seed: &[u8; SEED_SIZE]) -> KeyPair {
142            mldsa_core::generate_keypair_from_seed::<$variant, VERIFYING_KEY_SIZE>(seed)
143        }
144
145        pub fn sign(
146            seed: &[u8; SEED_SIZE],
147            message: &[u8],
148            context: Option<&[u8]>,
149        ) -> [u8; SIGNATURE_SIZE] {
150            mldsa_core::sign::<$variant, SIGNATURE_SIZE>(seed, message, context)
151        }
152
153        pub fn verify(
154            vk: &[u8; VERIFYING_KEY_SIZE],
155            message: &[u8],
156            sig: &[u8; SIGNATURE_SIZE],
157            context: Option<&[u8]>,
158        ) -> bool {
159            mldsa_core::verify::<$variant, VERIFYING_KEY_SIZE, SIGNATURE_SIZE>(
160                vk, message, sig, context,
161            )
162        }
163    };
164}
mldsa_core/lib.rs

mldsa_core/
lib.rs
