rsa/pkcs1v15/
verifying_key.rs

1use super::{oid, pkcs1v15_generate_prefix, verify, Signature};
2use crate::RsaPublicKey;
3use alloc::vec::Vec;
4use core::marker::PhantomData;
5use digest::Digest;
6use pkcs8::{
7    spki::{
8        der::AnyRef, AlgorithmIdentifierRef, AssociatedAlgorithmIdentifier,
9        SignatureAlgorithmIdentifier,
10    },
11    AssociatedOid, Document, EncodePublicKey,
12};
13use signature::{hazmat::PrehashVerifier, DigestVerifier, Verifier};
14
15/// Verifying key for `RSASSA-PKCS1-v1_5` signatures as described in [RFC8017 § 8.2].
16///
17/// [RFC8017 § 8.2]: https://datatracker.ietf.org/doc/html/rfc8017#section-8.2
18#[derive(Debug)]
19pub struct VerifyingKey<D>
20where
21    D: Digest,
22{
23    pub(super) inner: RsaPublicKey,
24    pub(super) prefix: Vec<u8>,
25    pub(super) phantom: PhantomData<D>,
26}
27
28impl<D> VerifyingKey<D>
29where
30    D: Digest + AssociatedOid,
31{
32    /// Create a new verifying key with a prefix for the digest `D`.
33    pub fn new(key: RsaPublicKey) -> Self {
34        Self {
35            inner: key,
36            prefix: pkcs1v15_generate_prefix::<D>(),
37            phantom: Default::default(),
38        }
39    }
40
41    /// Create a new verifying key with a prefix for the digest `D`.
42    #[deprecated(since = "0.9.0", note = "use VerifyingKey::new instead")]
43    pub fn new_with_prefix(key: RsaPublicKey) -> Self {
44        Self::new(key)
45    }
46}
47
48impl<D> VerifyingKey<D>
49where
50    D: Digest,
51{
52    /// Create a new verifying key from an RSA public key with an empty prefix.
53    ///
54    /// ## Note: unprefixed signatures are uncommon
55    ///
56    /// In most cases you'll want to use [`VerifyingKey::new`] instead.
57    pub fn new_unprefixed(key: RsaPublicKey) -> Self {
58        Self {
59            inner: key,
60            prefix: Vec::new(),
61            phantom: Default::default(),
62        }
63    }
64}
65
66//
67// `*Verifier` trait impls
68//
69
70impl<D> DigestVerifier<D, Signature> for VerifyingKey<D>
71where
72    D: Digest,
73{
74    fn verify_digest(&self, digest: D, signature: &Signature) -> signature::Result<()> {
75        verify(
76            &self.inner,
77            &self.prefix,
78            &digest.finalize(),
79            &signature.inner,
80            signature.len,
81        )
82        .map_err(|e| e.into())
83    }
84}
85
86impl<D> PrehashVerifier<Signature> for VerifyingKey<D>
87where
88    D: Digest,
89{
90    fn verify_prehash(&self, prehash: &[u8], signature: &Signature) -> signature::Result<()> {
91        verify(
92            &self.inner,
93            &self.prefix,
94            prehash,
95            &signature.inner,
96            signature.len,
97        )
98        .map_err(|e| e.into())
99    }
100}
101
102impl<D> Verifier<Signature> for VerifyingKey<D>
103where
104    D: Digest,
105{
106    fn verify(&self, msg: &[u8], signature: &Signature) -> signature::Result<()> {
107        verify(
108            &self.inner,
109            &self.prefix.clone(),
110            &D::digest(msg),
111            &signature.inner,
112            signature.len,
113        )
114        .map_err(|e| e.into())
115    }
116}
117
118//
119// Other trait impls
120//
121
122impl<D> AsRef<RsaPublicKey> for VerifyingKey<D>
123where
124    D: Digest,
125{
126    fn as_ref(&self) -> &RsaPublicKey {
127        &self.inner
128    }
129}
130
131impl<D> AssociatedAlgorithmIdentifier for VerifyingKey<D>
132where
133    D: Digest,
134{
135    type Params = AnyRef<'static>;
136
137    const ALGORITHM_IDENTIFIER: AlgorithmIdentifierRef<'static> = pkcs1::ALGORITHM_ID;
138}
139
140// Implemented manually so we don't have to bind D with Clone
141impl<D> Clone for VerifyingKey<D>
142where
143    D: Digest,
144{
145    fn clone(&self) -> Self {
146        Self {
147            inner: self.inner.clone(),
148            prefix: self.prefix.clone(),
149            phantom: Default::default(),
150        }
151    }
152}
153
154impl<D> EncodePublicKey for VerifyingKey<D>
155where
156    D: Digest,
157{
158    fn to_public_key_der(&self) -> pkcs8::spki::Result<Document> {
159        self.inner.to_public_key_der()
160    }
161}
162
163impl<D> From<RsaPublicKey> for VerifyingKey<D>
164where
165    D: Digest,
166{
167    fn from(key: RsaPublicKey) -> Self {
168        Self::new_unprefixed(key)
169    }
170}
171
172impl<D> From<VerifyingKey<D>> for RsaPublicKey
173where
174    D: Digest,
175{
176    fn from(key: VerifyingKey<D>) -> Self {
177        key.inner
178    }
179}
180
181impl<D> SignatureAlgorithmIdentifier for VerifyingKey<D>
182where
183    D: Digest + oid::RsaSignatureAssociatedOid,
184{
185    type Params = AnyRef<'static>;
186
187    const SIGNATURE_ALGORITHM_IDENTIFIER: AlgorithmIdentifierRef<'static> =
188        AlgorithmIdentifierRef {
189            oid: D::OID,
190            parameters: Some(AnyRef::NULL),
191        };
192}
193
194impl<D> TryFrom<pkcs8::SubjectPublicKeyInfoRef<'_>> for VerifyingKey<D>
195where
196    D: Digest + AssociatedOid,
197{
198    type Error = pkcs8::spki::Error;
199
200    fn try_from(spki: pkcs8::SubjectPublicKeyInfoRef<'_>) -> pkcs8::spki::Result<Self> {
201        RsaPublicKey::try_from(spki).map(Self::new)
202    }
203}
rsa/pkcs1v15/verifying_key.rs

rsa/pkcs1v15/
verifying_key.rs
