mail_auth/common/crypto/
ring_impls.rs

1/*
2 * SPDX-FileCopyrightText: 2020 Stalwart Labs LLC <hello@stalw.art>
3 *
4 * SPDX-License-Identifier: Apache-2.0 OR MIT
5 */
6
7use super::{Algorithm, HashContext, HashImpl, HashOutput, Sha1, Sha256, SigningKey, VerifyingKey};
8use crate::{
9    Error, Result,
10    common::headers::{Writable, Writer},
11    dkim::Canonicalization,
12};
13use ring::digest::{Context, SHA1_FOR_LEGACY_USE_ONLY, SHA256};
14use ring::rand::SystemRandom;
15use ring::signature::{
16    ED25519, Ed25519KeyPair, KeyPair, RSA_PKCS1_1024_8192_SHA1_FOR_LEGACY_USE_ONLY,
17    RSA_PKCS1_1024_8192_SHA256_FOR_LEGACY_USE_ONLY, RSA_PKCS1_SHA256, RsaKeyPair,
18    UnparsedPublicKey,
19};
20use rustls_pki_types::{PrivateKeyDer, PrivatePkcs1KeyDer, PrivatePkcs8KeyDer, pem::PemObject};
21use std::marker::PhantomData;
22
23#[derive(Debug)]
24pub struct RsaKey<T> {
25    inner: RsaKeyPair,
26    rng: SystemRandom,
27    padding: PhantomData<T>,
28}
29
30impl<T: HashImpl> RsaKey<T> {
31    #[deprecated(since = "0.7.4", note = "use `from_key_der()` instead")]
32    pub fn from_pkcs8_pem(pkcs8_pem: &str) -> Result<Self> {
33        Self::from_key_der(PrivateKeyDer::Pkcs8(
34            PrivatePkcs8KeyDer::from_pem_slice(pkcs8_pem.as_bytes())
35                .map_err(|err| Error::CryptoError(err.to_string()))?,
36        ))
37    }
38
39    /// Creates a new RSA private key from PKCS8 DER-encoded bytes.
40    #[deprecated(since = "0.7.4", note = "use `from_key_der()` instead")]
41    pub fn from_pkcs8_der(pkcs8_der: &[u8]) -> Result<Self> {
42        Self::from_key_der(PrivateKeyDer::Pkcs8(PrivatePkcs8KeyDer::from(pkcs8_der)))
43    }
44
45    #[deprecated(since = "0.7.4", note = "use `from_key_der()` instead")]
46    pub fn from_rsa_pem(rsa_pem: &str) -> Result<Self> {
47        Self::from_key_der(PrivateKeyDer::Pkcs1(
48            PrivatePkcs1KeyDer::from_pem_slice(rsa_pem.as_bytes())
49                .map_err(|err| Error::CryptoError(err.to_string()))?,
50        ))
51    }
52
53    /// Creates a new RSA private key from a PKCS1 binary slice.
54    #[deprecated(since = "0.7.4", note = "use `from_key_der()` instead")]
55    pub fn from_der(der: &[u8]) -> Result<Self> {
56        Self::from_key_der(PrivateKeyDer::Pkcs1(PrivatePkcs1KeyDer::from(der)))
57    }
58
59    /// Creates a new RSA private key from various DER-encoded key formats.
60    ///
61    /// Only supports PKCS1 and PKCS8 formats -- will yield an error for other formats.
62    pub fn from_key_der(key_der: PrivateKeyDer<'_>) -> Result<Self> {
63        let inner = match key_der {
64            PrivateKeyDer::Pkcs1(der) => RsaKeyPair::from_der(der.secret_pkcs1_der())
65                .map_err(|err| Error::CryptoError(err.to_string()))?,
66            PrivateKeyDer::Pkcs8(der) => RsaKeyPair::from_pkcs8(der.secret_pkcs8_der())
67                .map_err(|err| Error::CryptoError(err.to_string()))?,
68            _ => return Err(Error::CryptoError("Unsupported RSA key format".to_string())),
69        };
70
71        Ok(Self {
72            inner,
73            rng: SystemRandom::new(),
74            padding: PhantomData,
75        })
76    }
77
78    /// Returns the public key of the RSA key pair.
79    pub fn public_key(&self) -> Vec<u8> {
80        self.inner.public().as_ref().to_vec()
81    }
82}
83
84impl SigningKey for RsaKey<Sha256> {
85    type Hasher = Sha256;
86
87    fn sign(&self, input: impl Writable) -> Result<Vec<u8>> {
88        let mut data = Vec::with_capacity(256);
89        input.write(&mut data);
90
91        let mut signature = vec![0; self.inner.public().modulus_len()];
92        self.inner
93            .sign(&RSA_PKCS1_SHA256, &self.rng, &data, &mut signature)
94            .map_err(|err| Error::CryptoError(err.to_string()))?;
95        Ok(signature)
96    }
97
98    fn algorithm(&self) -> Algorithm {
99        Algorithm::RsaSha256
100    }
101}
102
103pub struct Ed25519Key {
104    inner: Ed25519KeyPair,
105}
106
107impl Ed25519Key {
108    pub fn generate_pkcs8() -> Result<Vec<u8>> {
109        Ok(Ed25519KeyPair::generate_pkcs8(&SystemRandom::new())
110            .map_err(|err| Error::CryptoError(err.to_string()))?
111            .as_ref()
112            .to_vec())
113    }
114
115    pub fn from_pkcs8_der(pkcs8_der: &[u8]) -> Result<Self> {
116        Ok(Self {
117            inner: Ed25519KeyPair::from_pkcs8(pkcs8_der)
118                .map_err(|err| Error::CryptoError(err.to_string()))?,
119        })
120    }
121
122    pub fn from_pkcs8_maybe_unchecked_der(pkcs8_der: &[u8]) -> Result<Self> {
123        Ok(Self {
124            inner: Ed25519KeyPair::from_pkcs8_maybe_unchecked(pkcs8_der)
125                .map_err(|err| Error::CryptoError(err.to_string()))?,
126        })
127    }
128
129    pub fn from_seed_and_public_key(seed: &[u8], public_key: &[u8]) -> Result<Self> {
130        Ok(Self {
131            inner: Ed25519KeyPair::from_seed_and_public_key(seed, public_key)
132                .map_err(|err| Error::CryptoError(err.to_string()))?,
133        })
134    }
135
136    // Returns the public key of the Ed25519 key pair.
137    pub fn public_key(&self) -> Vec<u8> {
138        self.inner.public_key().as_ref().to_vec()
139    }
140}
141
142impl SigningKey for Ed25519Key {
143    type Hasher = Sha256;
144
145    fn sign(&self, input: impl Writable) -> Result<Vec<u8>> {
146        let mut data = Sha256::hasher();
147        input.write(&mut data);
148        Ok(self.inner.sign(data.complete().as_ref()).as_ref().to_vec())
149    }
150
151    fn algorithm(&self) -> Algorithm {
152        Algorithm::Ed25519Sha256
153    }
154}
155
156pub(crate) struct RsaPublicKey {
157    sha1: UnparsedPublicKey<Vec<u8>>,
158    sha2: UnparsedPublicKey<Vec<u8>>,
159}
160
161impl RsaPublicKey {
162    pub(crate) fn verifying_key_from_bytes(
163        bytes: &[u8],
164    ) -> Result<Box<dyn VerifyingKey + Send + Sync>> {
165        let key = try_strip_rsa_prefix(bytes).unwrap_or(bytes);
166        Ok(Box::new(Self {
167            sha1: UnparsedPublicKey::new(
168                &RSA_PKCS1_1024_8192_SHA1_FOR_LEGACY_USE_ONLY,
169                key.to_vec(),
170            ),
171            sha2: UnparsedPublicKey::new(
172                &RSA_PKCS1_1024_8192_SHA256_FOR_LEGACY_USE_ONLY,
173                key.to_vec(),
174            ),
175        }))
176    }
177}
178
179/// Try to strip an ASN.1 DER-encoded RSA public key prefix
180///
181/// Returns the original slice if the prefix is not found.
182fn try_strip_rsa_prefix(bytes: &[u8]) -> Option<&[u8]> {
183    if *bytes.first()? != DER_SEQUENCE_TAG {
184        return None;
185    }
186
187    let (_, bytes) = decode_multi_byte_len(&bytes[1..])?;
188    if *bytes.first()? != DER_SEQUENCE_TAG {
189        return None;
190    }
191
192    let (byte_len, bytes) = decode_multi_byte_len(&bytes[1..])?;
193    if *bytes.first()? != DER_OBJECT_ID_TAG || byte_len != 13 {
194        return None;
195    }
196
197    let bytes = bytes.get(13..)?; // skip the RSA encryption OID
198    if *bytes.first()? != DER_BIT_STRING_TAG {
199        return None;
200    }
201
202    decode_multi_byte_len(&bytes[1..]).and_then(|(_, bytes)| bytes.get(1..)) // skip the unused bits byte
203}
204
205fn decode_multi_byte_len(bytes: &[u8]) -> Option<(usize, &[u8])> {
206    if bytes.first()? & 0x80 == 0 {
207        return Some((bytes[0] as usize, &bytes[1..]));
208    }
209
210    let len_len = (bytes[0] & 0x7f) as usize;
211    if bytes.len() < len_len + 1 {
212        return None;
213    }
214
215    let mut len = 0;
216    for i in 0..len_len {
217        len = (len << 8) | bytes[1 + i] as usize;
218    }
219
220    Some((len, &bytes[len_len + 1..]))
221}
222
223const DER_OBJECT_ID_TAG: u8 = 0x06;
224const DER_BIT_STRING_TAG: u8 = 0x03;
225const DER_SEQUENCE_TAG: u8 = 0x30;
226
227impl VerifyingKey for RsaPublicKey {
228    fn verify<'a>(
229        &self,
230        headers: &mut dyn Iterator<Item = (&'a [u8], &'a [u8])>,
231        signature: &[u8],
232        canonicalization: Canonicalization,
233        algorithm: Algorithm,
234    ) -> Result<()> {
235        let mut data = Vec::with_capacity(256);
236        canonicalization.canonicalize_headers(headers, &mut data);
237
238        match algorithm {
239            Algorithm::RsaSha256 => self
240                .sha2
241                .verify(&data, signature)
242                .map_err(|_| Error::FailedVerification),
243            Algorithm::RsaSha1 => self
244                .sha1
245                .verify(&data, signature)
246                .map_err(|_| Error::FailedVerification),
247            Algorithm::Ed25519Sha256 => Err(Error::IncompatibleAlgorithms),
248        }
249    }
250}
251
252pub(crate) struct Ed25519PublicKey {
253    inner: UnparsedPublicKey<Vec<u8>>,
254}
255
256impl Ed25519PublicKey {
257    pub(crate) fn verifying_key_from_bytes(
258        bytes: &[u8],
259    ) -> Result<Box<dyn VerifyingKey + Send + Sync>> {
260        Ok(Box::new(Self {
261            inner: UnparsedPublicKey::new(&ED25519, bytes.to_vec()),
262        }))
263    }
264}
265
266impl VerifyingKey for Ed25519PublicKey {
267    fn verify<'a>(
268        &self,
269        headers: &mut dyn Iterator<Item = (&'a [u8], &'a [u8])>,
270        signature: &[u8],
271        canonicalization: Canonicalization,
272        algorithm: Algorithm,
273    ) -> Result<()> {
274        if !matches!(algorithm, Algorithm::Ed25519Sha256) {
275            return Err(Error::IncompatibleAlgorithms);
276        }
277
278        let mut hasher = Sha256::hasher();
279        canonicalization.canonicalize_headers(headers, &mut hasher);
280        self.inner
281            .verify(hasher.complete().as_ref(), signature)
282            .map_err(|err| Error::CryptoError(err.to_string()))
283    }
284}
285
286impl HashImpl for Sha1 {
287    type Context = Context;
288
289    fn hasher() -> Self::Context {
290        Context::new(&SHA1_FOR_LEGACY_USE_ONLY)
291    }
292}
293
294impl HashImpl for Sha256 {
295    type Context = Context;
296
297    fn hasher() -> Self::Context {
298        Context::new(&SHA256)
299    }
300}
301
302impl HashContext for Context {
303    fn complete(self) -> HashOutput {
304        HashOutput::Ring(self.finish())
305    }
306}
307
308impl Writer for Context {
309    fn write(&mut self, data: &[u8]) {
310        self.update(data);
311    }
312}
313
314#[cfg(test)]
315mod tests {
316    use super::*;
317
318    #[test]
319    fn from_key_der_pkcs1() {
320        let key_der = PrivateKeyDer::from_pem_slice(PKCS1_PEM.as_bytes()).unwrap();
321        assert!(matches!(key_der, PrivateKeyDer::Pkcs1(_)));
322        RsaKey::<Sha256>::from_key_der(key_der).unwrap();
323    }
324
325    #[test]
326    fn from_key_der_pkcs8() {
327        let key_der = PrivateKeyDer::from_pem_slice(PKCS8_PEM.as_bytes()).unwrap();
328        assert!(matches!(key_der, PrivateKeyDer::Pkcs8(_)));
329        RsaKey::<Sha256>::from_key_der(key_der).unwrap();
330    }
331
332    const PKCS1_PEM: &str = r#"-----BEGIN RSA PRIVATE KEY-----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358-----END RSA PRIVATE KEY-----
359"#;
360
361    const PKCS8_PEM: &str = r#"-----BEGIN PRIVATE KEY-----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388-----END PRIVATE KEY-----
389"#;
390}
mail_auth/common/crypto/ring_impls.rs

mail_auth/common/crypto/
ring_impls.rs
