libpep 0.12.0

Library for polymorphic encryption and pseudonymization
Documentation 
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
167
168
169
170

//! Traits for public and secret keys.

use super::types::*;
use crate::arithmetic::group_elements::GroupElement;
use crate::arithmetic::scalars::ScalarNonZero;

/// A trait for public keys, which can be encoded and decoded from byte arrays and hex strings.
pub trait PublicKey {
    fn value(&self) -> &GroupElement;
    fn to_bytes(&self) -> [u8; 32] {
        self.value().to_bytes()
    }
    fn to_hex(&self) -> String {
        self.value().to_hex()
    }
    fn from_bytes(bytes: &[u8; 32]) -> Option<Self>
    where
        Self: Sized;
    fn from_slice(slice: &[u8]) -> Option<Self>
    where
        Self: Sized;
    fn from_hex(s: &str) -> Option<Self>
    where
        Self: Sized;
}

/// A trait for secret keys, for which we do not allow encoding as secret keys should not be shared.
pub trait SecretKey {
    fn value(&self) -> &ScalarNonZero;
}

impl PublicKey for PseudonymGlobalPublicKey {
    fn value(&self) -> &GroupElement {
        &self.0
    }

    fn from_bytes(bytes: &[u8; 32]) -> Option<Self> {
        GroupElement::from_bytes(bytes).map(Self::from)
    }
    fn from_slice(slice: &[u8]) -> Option<Self> {
        GroupElement::from_slice(slice).map(PseudonymGlobalPublicKey::from)
    }
    fn from_hex(s: &str) -> Option<Self> {
        GroupElement::from_hex(s).map(PseudonymGlobalPublicKey::from)
    }
}

impl SecretKey for PseudonymGlobalSecretKey {
    fn value(&self) -> &ScalarNonZero {
        &self.0
    }
}

impl PublicKey for AttributeGlobalPublicKey {
    fn value(&self) -> &GroupElement {
        &self.0
    }

    fn from_bytes(bytes: &[u8; 32]) -> Option<Self> {
        GroupElement::from_bytes(bytes).map(Self::from)
    }
    fn from_slice(slice: &[u8]) -> Option<Self> {
        GroupElement::from_slice(slice).map(AttributeGlobalPublicKey::from)
    }
    fn from_hex(s: &str) -> Option<Self> {
        GroupElement::from_hex(s).map(AttributeGlobalPublicKey::from)
    }
}

impl SecretKey for AttributeGlobalSecretKey {
    fn value(&self) -> &ScalarNonZero {
        &self.0
    }
}

impl PublicKey for PseudonymSessionPublicKey {
    fn value(&self) -> &GroupElement {
        &self.0
    }
    fn from_bytes(bytes: &[u8; 32]) -> Option<Self> {
        GroupElement::from_bytes(bytes).map(Self::from)
    }
    fn from_slice(slice: &[u8]) -> Option<Self> {
        GroupElement::from_slice(slice).map(PseudonymSessionPublicKey::from)
    }
    fn from_hex(s: &str) -> Option<Self> {
        GroupElement::from_hex(s).map(PseudonymSessionPublicKey::from)
    }
}

impl SecretKey for PseudonymSessionSecretKey {
    fn value(&self) -> &ScalarNonZero {
        &self.0
    }
}

impl PublicKey for AttributeSessionPublicKey {
    fn value(&self) -> &GroupElement {
        &self.0
    }
    fn from_bytes(bytes: &[u8; 32]) -> Option<Self> {
        GroupElement::from_bytes(bytes).map(Self::from)
    }
    fn from_slice(slice: &[u8]) -> Option<Self> {
        GroupElement::from_slice(slice).map(AttributeSessionPublicKey::from)
    }
    fn from_hex(s: &str) -> Option<Self> {
        GroupElement::from_hex(s).map(AttributeSessionPublicKey::from)
    }
}

impl SecretKey for AttributeSessionSecretKey {
    fn value(&self) -> &ScalarNonZero {
        &self.0
    }
}

/// Trait to provide the correct key from SessionKeys or GlobalPublicKeys based on the key type.
/// This enables polymorphic key access in the Client.
pub trait KeyProvider<K> {
    fn get_key(&self) -> &K;
}

impl KeyProvider<PseudonymSessionPublicKey> for SessionKeys {
    fn get_key(&self) -> &PseudonymSessionPublicKey {
        &self.pseudonym.public
    }
}

impl KeyProvider<AttributeSessionPublicKey> for SessionKeys {
    fn get_key(&self) -> &AttributeSessionPublicKey {
        &self.attribute.public
    }
}

impl KeyProvider<PseudonymSessionSecretKey> for SessionKeys {
    fn get_key(&self) -> &PseudonymSessionSecretKey {
        &self.pseudonym.secret
    }
}

impl KeyProvider<AttributeSessionSecretKey> for SessionKeys {
    fn get_key(&self) -> &AttributeSessionSecretKey {
        &self.attribute.secret
    }
}

impl KeyProvider<SessionKeys> for SessionKeys {
    fn get_key(&self) -> &SessionKeys {
        self
    }
}

impl KeyProvider<PseudonymGlobalPublicKey> for GlobalPublicKeys {
    fn get_key(&self) -> &PseudonymGlobalPublicKey {
        &self.pseudonym
    }
}

impl KeyProvider<AttributeGlobalPublicKey> for GlobalPublicKeys {
    fn get_key(&self) -> &AttributeGlobalPublicKey {
        &self.attribute
    }
}

impl KeyProvider<GlobalPublicKeys> for GlobalPublicKeys {
    fn get_key(&self) -> &GlobalPublicKeys {
        self
    }
}