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
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166

use std::collections::hash_map;
use std::sync::Arc;

use anyhow::Result;
use everscale_crypto::ed25519;

use super::node_id::{ComputeNodeIds, NodeIdFull, NodeIdShort};
use crate::util::FastHashMap;

/// Tagged keystore for ADNL keys
#[derive(Default)]
pub struct Keystore {
    keys: FastHashMap<NodeIdShort, Arc<Key>>,
    tags: FastHashMap<usize, NodeIdShort>,
}

impl Keystore {
    pub fn builder() -> KeystoreBuilder {
        KeystoreBuilder::default()
    }

    /// Searches key by its short id
    pub fn key_by_id(&self, id: &NodeIdShort) -> Result<&Arc<Key>, KeystoreError> {
        if let Some(key) = self.keys.get(id) {
            Ok(key)
        } else {
            Err(KeystoreError::KeyIdNotFound(*id))
        }
    }

    /// Searches key by its tag
    pub fn key_by_tag(&self, tag: usize) -> Result<&Arc<Key>, KeystoreError> {
        if let Some(id) = self.tags.get(&tag) {
            self.key_by_id(id)
        } else {
            Err(KeystoreError::KeyTagNotFound(tag))
        }
    }

    /// Returns inner keys table
    #[inline(always)]
    pub fn keys(&self) -> &FastHashMap<NodeIdShort, Arc<Key>> {
        &self.keys
    }

    /// Adds a new key with the specified tag
    ///
    /// NOTE: duplicate keys or tags will cause this method to fail
    pub fn add_key(&mut self, key: [u8; 32], tag: usize) -> Result<NodeIdShort, KeystoreError> {
        let secret_key = ed25519::SecretKey::from_bytes(key);
        let (_, short_id) = secret_key.compute_node_ids();

        match self.tags.entry(tag) {
            hash_map::Entry::Vacant(entry) => {
                entry.insert(short_id);
                match self.keys.entry(short_id) {
                    hash_map::Entry::Vacant(entry) => {
                        entry.insert(Arc::new(secret_key.into()));
                        Ok(short_id)
                    }
                    hash_map::Entry::Occupied(_) => Err(KeystoreError::DuplicatedKey(tag)),
                }
            }
            hash_map::Entry::Occupied(entry) => {
                if entry.get() == &short_id {
                    Ok(short_id)
                } else {
                    Err(KeystoreError::DuplicatedKeyTag(tag))
                }
            }
        }
    }
}

#[derive(Default)]
pub struct KeystoreBuilder {
    keystore: Keystore,
}

impl KeystoreBuilder {
    pub fn build(self) -> Keystore {
        self.keystore
    }

    /// Adds a new key with the specified tag
    ///
    /// NOTE: duplicate keys or tags will cause this method to fail
    pub fn with_tagged_key(mut self, key: [u8; 32], tag: usize) -> Result<Self, KeystoreError> {
        self.keystore.add_key(key, tag)?;
        Ok(self)
    }

    /// Creates a new keystore from tagged secret keys
    pub fn with_tagged_keys<I>(mut self, keys: I) -> Result<Self, KeystoreError>
    where
        I: IntoIterator<Item = ([u8; 32], usize)>,
    {
        for (key, tag) in keys {
            self.keystore.add_key(key, tag)?;
        }
        Ok(self)
    }
}

/// ADNL key with precomputed node IDs
pub struct Key {
    short_id: NodeIdShort,
    full_id: NodeIdFull,
    secret_key: ed25519::ExpandedSecretKey,
}

impl Key {
    /// Constructs new key from the secret key bytes
    pub fn from_bytes(secret_key: [u8; 32]) -> Self {
        ed25519::SecretKey::from_bytes(secret_key).into()
    }

    /// Returns short key id
    #[inline(always)]
    pub fn id(&self) -> &NodeIdShort {
        &self.short_id
    }

    /// Returns full key id
    #[inline(always)]
    pub fn full_id(&self) -> &NodeIdFull {
        &self.full_id
    }

    /// Returns inner secret key (as expanded)
    #[inline(always)]
    pub fn secret_key(&self) -> &ed25519::ExpandedSecretKey {
        &self.secret_key
    }

    /// Signs serializable boxed data
    #[inline(always)]
    pub fn sign<T: tl_proto::TlWrite<Repr = tl_proto::Boxed>>(&self, data: T) -> [u8; 64] {
        self.secret_key.sign(data, self.full_id.public_key())
    }
}

impl From<ed25519::SecretKey> for Key {
    fn from(secret_key: ed25519::SecretKey) -> Self {
        let (full_id, short_id) = secret_key.compute_node_ids();
        Self {
            short_id,
            full_id,
            secret_key: ed25519::ExpandedSecretKey::from(&secret_key),
        }
    }
}

#[derive(thiserror::Error, Debug)]
pub enum KeystoreError {
    #[error("Duplicated key tag {0}")]
    DuplicatedKeyTag(usize),
    #[error("Duplicated secret key {0}")]
    DuplicatedKey(usize),
    #[error("Key is not found: {0}")]
    KeyIdNotFound(NodeIdShort),
    #[error("Key tag not found: {0}")]
    KeyTagNotFound(usize),
    #[error("Unexpected key")]
    UnexpectedKey,
}