dkls23/setup/key_export/
exporter.rs

1// Copyright (c) Silence Laboratories Pte. Ltd. All Rights Reserved.
2// This software is licensed under the Silence Laboratories License Agreement.
3
4use super::*;
5
6/// A message used for setting up key export operations in a multi-party computation protocol.
7///
8/// This struct encapsulates all necessary information for exporting a key,
9/// including participant information, cryptographic keys, and protocol parameters.
10///
11/// # Type Parameters
12/// * `SK` - The type of signing key used for message signatures
13/// * `VK` - The type of verifying key used to verify message signatures
14/// * `MS` - The type of message signature
15/// * `KS` - The type of keyshare used in the protocol
16pub struct KeyExporter<
17    SK = NoSigningKey,
18    VK = NoVerifyingKey,
19    MS = NoSignature,
20    KS = Keyshare,
21> {
22    /// ID of the current party
23    party_id: usize,
24    /// Signing key for the current party
25    sk: SK,
26    /// Verifying keys for all participants
27    vk: Vec<VK>,
28    /// Instance identifier for the protocol
29    inst: InstanceId,
30    /// Time-to-live duration for messages
31    ttl: Duration,
32    /// Public key of the receiver
33    pub_key: PublicKey,
34    /// Reference to the keyshare to be exported
35    share: Arc<KS>,
36    /// Phantom data to hold the message signature type
37    marker: PhantomData<MS>,
38}
39
40impl<SK, VK, MS, KS> KeyExporter<SK, VK, MS, KS> {
41    /// Creates a new setup message for key export operations.
42    ///
43    /// # Arguments
44    /// * `inst` - Instance identifier for the protocol
45    /// * `sk` - Signing key for the current party
46    /// * `party_id` - ID of the current party
47    /// * `vk` - Vector of verifying keys for all participants
48    /// * `share` - Reference to the keyshare to be exported
49    /// * `enc_pub_key` - Public key of the receiver
50    ///
51    /// # Returns
52    /// A new `KeyExporter` instance with default TTL
53    pub fn new(
54        inst: InstanceId,
55        sk: SK,
56        party_id: usize,
57        vk: Vec<VK>,
58        share: Arc<KS>,
59        enc_pub_key: PublicKey,
60    ) -> Self {
61        Self {
62            party_id,
63            sk,
64            vk,
65            inst,
66            ttl: Duration::from_secs(DEFAULT_TTL),
67            marker: PhantomData,
68            pub_key: enc_pub_key,
69            share,
70        }
71    }
72
73    /// Returns a reference to the keyshare to be exported.
74    pub fn keyshare(&self) -> &KS {
75        &self.share
76    }
77
78    /// Sets a custom time-to-live duration for messages.
79    ///
80    /// # Arguments
81    /// * `ttl` - The new time-to-live duration
82    ///
83    /// # Returns
84    /// The modified `KeyExporter` instance
85    pub fn with_ttl(mut self, ttl: Duration) -> Self {
86        self.ttl = ttl;
87        self
88    }
89}
90
91impl<SK, VK, MS, KS> ProtocolParticipant for KeyExporter<SK, VK, MS, KS>
92where
93    SK: Signer<MS>,
94    MS: SignatureEncoding,
95    VK: AsRef<[u8]> + Verifier<MS>,
96{
97    type MessageSignature = MS;
98    type MessageSigner = SK;
99    type MessageVerifier = VK;
100
101    /// Returns the total number of participants in the protocol.
102    fn total_participants(&self) -> usize {
103        self.vk.len()
104    }
105
106    /// Returns the index of the current participant.
107    fn participant_index(&self) -> usize {
108        self.party_id
109    }
110
111    /// Returns the instance identifier for the protocol.
112    fn instance_id(&self) -> &InstanceId {
113        &self.inst
114    }
115
116    /// Returns the time-to-live duration for messages.
117    fn message_ttl(&self) -> Duration {
118        self.ttl
119    }
120
121    /// Returns the verifying key for a specific participant.
122    ///
123    /// # Arguments
124    /// * `index` - The index of the participant
125    ///
126    /// # Returns
127    /// A reference to the verifying key
128    fn verifier(&self, index: usize) -> &Self::MessageVerifier {
129        &self.vk[index]
130    }
131
132    /// Returns the signing key for the current participant.
133    fn signer(&self) -> &Self::MessageSigner {
134        &self.sk
135    }
136}
137
138impl<SK, VK, MS, KS> setup::KeyExporterSetupMessage<PublicKey, KS>
139    for KeyExporter<SK, VK, MS, KS>
140where
141    SK: Signer<MS>,
142    MS: SignatureEncoding,
143    VK: AsRef<[u8]> + Verifier<MS>,
144{
145    /// Returns the public key of the receiver.
146    fn receiver_public_key(&self) -> &PublicKey {
147        &self.pub_key
148    }
149
150    /// Returns a reference to the keyshare to be exported.
151    fn keyshare(&self) -> &KS {
152        &self.share
153    }
154}
dkls23/setup/key_export/exporter.rs

dkls23/setup/key_export/
exporter.rs
