commonware_cryptography/ed25519/
scheme.rs

1use crate::{Array, BatchScheme, Signer, Specification, Verifier};
2use bytes::{Buf, BufMut};
3use commonware_codec::{Error as CodecError, FixedSize, Read, ReadExt, Write};
4use commonware_utils::{hex, union_unique};
5use ed25519_consensus::{self, VerificationKey};
6use rand::{CryptoRng, Rng, RngCore};
7use std::borrow::Cow;
8use std::fmt::{Debug, Display};
9use std::hash::{Hash, Hasher};
10use std::ops::Deref;
11
12const CURVE_NAME: &str = "ed25519";
13const PRIVATE_KEY_LENGTH: usize = 32;
14const PUBLIC_KEY_LENGTH: usize = 32;
15const SIGNATURE_LENGTH: usize = 64;
16
17/// Ed25519 Signer.
18#[derive(Clone)]
19pub struct Ed25519 {
20    signer: ed25519_consensus::SigningKey,
21    verifier: ed25519_consensus::VerificationKey,
22}
23
24impl Specification for Ed25519 {
25    type PublicKey = PublicKey;
26    type Signature = Signature;
27}
28
29impl Verifier for Ed25519 {
30    fn verify(
31        namespace: Option<&[u8]>,
32        message: &[u8],
33        public_key: &Self::PublicKey,
34        signature: &Self::Signature,
35    ) -> bool {
36        match namespace {
37            Some(namespace) => {
38                let payload = union_unique(namespace, message);
39                public_key
40                    .key
41                    .verify(&signature.signature, &payload)
42                    .is_ok()
43            }
44            None => public_key.key.verify(&signature.signature, message).is_ok(),
45        }
46    }
47}
48
49impl Signer for Ed25519 {
50    type PrivateKey = PrivateKey;
51
52    fn new<R: CryptoRng + Rng>(r: &mut R) -> Self {
53        let signer = ed25519_consensus::SigningKey::new(r);
54        let verifier = signer.verification_key();
55        Self { signer, verifier }
56    }
57
58    fn from(private_key: PrivateKey) -> Option<Self> {
59        let signer = private_key.key;
60        let verifier = signer.verification_key();
61        Some(Self { signer, verifier })
62    }
63
64    fn private_key(&self) -> PrivateKey {
65        PrivateKey::from(self.signer.clone())
66    }
67
68    fn public_key(&self) -> PublicKey {
69        PublicKey::from(self.verifier)
70    }
71
72    fn sign(&mut self, namespace: Option<&[u8]>, message: &[u8]) -> Signature {
73        let sig = match namespace {
74            Some(namespace) => self.signer.sign(&union_unique(namespace, message)),
75            None => self.signer.sign(message),
76        };
77        Signature::from(sig)
78    }
79}
80
81/// Ed25519 Batch Verifier.
82pub struct Ed25519Batch {
83    verifier: ed25519_consensus::batch::Verifier,
84}
85
86impl Specification for Ed25519Batch {
87    type PublicKey = PublicKey;
88    type Signature = Signature;
89}
90
91impl BatchScheme for Ed25519Batch {
92    fn new() -> Self {
93        Ed25519Batch {
94            verifier: ed25519_consensus::batch::Verifier::new(),
95        }
96    }
97
98    fn add(
99        &mut self,
100        namespace: Option<&[u8]>,
101        message: &[u8],
102        public_key: &Self::PublicKey,
103        signature: &Self::Signature,
104    ) -> bool {
105        let payload = match namespace {
106            Some(namespace) => Cow::Owned(union_unique(namespace, message)),
107            None => Cow::Borrowed(message),
108        };
109        let item = ed25519_consensus::batch::Item::from((
110            public_key.key.into(),
111            signature.signature,
112            &payload,
113        ));
114        self.verifier.queue(item);
115        true
116    }
117
118    fn verify<R: RngCore + CryptoRng>(self, rng: &mut R) -> bool {
119        self.verifier.verify(rng).is_ok()
120    }
121}
122
123/// Ed25519 Private Key.
124#[derive(Clone)]
125pub struct PrivateKey {
126    raw: [u8; PRIVATE_KEY_LENGTH],
127    key: ed25519_consensus::SigningKey,
128}
129
130impl Write for PrivateKey {
131    fn write(&self, buf: &mut impl BufMut) {
132        self.raw.write(buf);
133    }
134}
135
136impl Read for PrivateKey {
137    fn read_cfg(buf: &mut impl Buf, _: &()) -> Result<Self, CodecError> {
138        let raw = <[u8; Self::SIZE]>::read(buf)?;
139        let key = ed25519_consensus::SigningKey::from(raw);
140        Ok(Self { raw, key })
141    }
142}
143
144impl FixedSize for PrivateKey {
145    const SIZE: usize = PRIVATE_KEY_LENGTH;
146}
147
148impl Array for PrivateKey {}
149
150impl Eq for PrivateKey {}
151
152impl Hash for PrivateKey {
153    fn hash<H: Hasher>(&self, state: &mut H) {
154        self.raw.hash(state);
155    }
156}
157
158impl PartialEq for PrivateKey {
159    fn eq(&self, other: &Self) -> bool {
160        self.raw == other.raw
161    }
162}
163
164impl Ord for PrivateKey {
165    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
166        self.raw.cmp(&other.raw)
167    }
168}
169
170impl PartialOrd for PrivateKey {
171    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
172        Some(self.cmp(other))
173    }
174}
175
176impl AsRef<[u8]> for PrivateKey {
177    fn as_ref(&self) -> &[u8] {
178        &self.raw
179    }
180}
181
182impl Deref for PrivateKey {
183    type Target = [u8];
184    fn deref(&self) -> &[u8] {
185        &self.raw
186    }
187}
188
189impl From<ed25519_consensus::SigningKey> for PrivateKey {
190    fn from(key: ed25519_consensus::SigningKey) -> Self {
191        let raw = key.to_bytes();
192        Self { raw, key }
193    }
194}
195
196impl Debug for PrivateKey {
197    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
198        write!(f, "{}", hex(&self.raw))
199    }
200}
201
202impl Display for PrivateKey {
203    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
204        write!(f, "{}", hex(&self.raw))
205    }
206}
207
208/// Ed25519 Public Key.
209#[derive(Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
210pub struct PublicKey {
211    raw: [u8; PUBLIC_KEY_LENGTH],
212    key: ed25519_consensus::VerificationKey,
213}
214
215impl Write for PublicKey {
216    fn write(&self, buf: &mut impl BufMut) {
217        self.raw.write(buf);
218    }
219}
220
221impl Read for PublicKey {
222    fn read_cfg(buf: &mut impl Buf, _: &()) -> Result<Self, CodecError> {
223        let raw = <[u8; Self::SIZE]>::read(buf)?;
224        let key = VerificationKey::try_from(raw)
225            .map_err(|e| CodecError::Wrapped(CURVE_NAME, e.into()))?;
226        Ok(Self { raw, key })
227    }
228}
229
230impl FixedSize for PublicKey {
231    const SIZE: usize = PUBLIC_KEY_LENGTH;
232}
233
234impl Array for PublicKey {}
235
236impl AsRef<[u8]> for PublicKey {
237    fn as_ref(&self) -> &[u8] {
238        &self.raw
239    }
240}
241
242impl Deref for PublicKey {
243    type Target = [u8];
244    fn deref(&self) -> &[u8] {
245        &self.raw
246    }
247}
248
249impl From<VerificationKey> for PublicKey {
250    fn from(key: VerificationKey) -> Self {
251        let raw = key.to_bytes();
252        Self { raw, key }
253    }
254}
255
256impl Debug for PublicKey {
257    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
258        write!(f, "{}", hex(&self.raw))
259    }
260}
261
262impl Display for PublicKey {
263    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
264        write!(f, "{}", hex(&self.raw))
265    }
266}
267
268/// Ed25519 Signature.
269#[derive(Clone, Eq, PartialEq)]
270pub struct Signature {
271    raw: [u8; SIGNATURE_LENGTH],
272    signature: ed25519_consensus::Signature,
273}
274
275impl Write for Signature {
276    fn write(&self, buf: &mut impl BufMut) {
277        self.raw.write(buf);
278    }
279}
280
281impl Read for Signature {
282    fn read_cfg(buf: &mut impl Buf, _: &()) -> Result<Self, CodecError> {
283        let raw = <[u8; Self::SIZE]>::read(buf)?;
284        let signature = ed25519_consensus::Signature::from(raw);
285        Ok(Self { raw, signature })
286    }
287}
288
289impl FixedSize for Signature {
290    const SIZE: usize = SIGNATURE_LENGTH;
291}
292
293impl Array for Signature {}
294
295impl Hash for Signature {
296    fn hash<H: Hasher>(&self, state: &mut H) {
297        self.raw.hash(state);
298    }
299}
300
301impl Ord for Signature {
302    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
303        self.raw.cmp(&other.raw)
304    }
305}
306
307impl PartialOrd for Signature {
308    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
309        Some(self.cmp(other))
310    }
311}
312
313impl AsRef<[u8]> for Signature {
314    fn as_ref(&self) -> &[u8] {
315        &self.raw
316    }
317}
318
319impl Deref for Signature {
320    type Target = [u8];
321    fn deref(&self) -> &[u8] {
322        &self.raw
323    }
324}
325
326impl From<ed25519_consensus::Signature> for Signature {
327    fn from(value: ed25519_consensus::Signature) -> Self {
328        let raw = value.to_bytes();
329        Self {
330            raw,
331            signature: value,
332        }
333    }
334}
335
336impl Debug for Signature {
337    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
338        write!(f, "{}", hex(&self.raw))
339    }
340}
341
342impl Display for Signature {
343    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
344        write!(f, "{}", hex(&self.raw))
345    }
346}
347
348/// Test vectors sourced from https://datatracker.ietf.org/doc/html/rfc8032#section-7.1.
349#[cfg(test)]
350mod tests {
351    use super::*;
352    use commonware_codec::{DecodeExt, Encode};
353    use rand::rngs::OsRng;
354
355    fn test_sign_and_verify(
356        private_key: PrivateKey,
357        public_key: PublicKey,
358        message: &[u8],
359        signature: Signature,
360    ) {
361        let mut signer = <Ed25519 as Signer>::from(private_key).unwrap();
362        let computed_signature = signer.sign(None, message);
363        assert_eq!(computed_signature, signature);
364        assert!(Ed25519::verify(
365            None,
366            message,
367            &public_key,
368            &computed_signature
369        ));
370    }
371
372    fn parse_private_key(private_key: &str) -> PrivateKey {
373        PrivateKey::decode(
374            commonware_utils::from_hex_formatted(private_key)
375                .unwrap()
376                .as_ref(),
377        )
378        .unwrap()
379    }
380
381    fn parse_public_key(public_key: &str) -> PublicKey {
382        PublicKey::decode(
383            commonware_utils::from_hex_formatted(public_key)
384                .unwrap()
385                .as_ref(),
386        )
387        .unwrap()
388    }
389
390    fn parse_signature(signature: &str) -> Signature {
391        Signature::decode(
392            commonware_utils::from_hex_formatted(signature)
393                .unwrap()
394                .as_ref(),
395        )
396        .unwrap()
397    }
398
399    fn vector_1() -> (PrivateKey, PublicKey, Vec<u8>, Signature) {
400        (
401            // secret key
402            parse_private_key(
403                "
404                9d61b19deffd5a60ba844af492ec2cc4
405                4449c5697b326919703bac031cae7f60
406                ",
407            ),
408            // public key
409            parse_public_key(
410                "
411                d75a980182b10ab7d54bfed3c964073a
412                0ee172f3daa62325af021a68f707511a
413                ",
414            ),
415            // message
416            b"".to_vec(),
417            // signature
418            parse_signature(
419                "
420                e5564300c360ac729086e2cc806e828a
421                84877f1eb8e5d974d873e06522490155
422                5fb8821590a33bacc61e39701cf9b46b
423                d25bf5f0595bbe24655141438e7a100b
424                ",
425            ),
426        )
427    }
428
429    fn vector_2() -> (PrivateKey, PublicKey, Vec<u8>, Signature) {
430        (
431            // secret key
432            parse_private_key(
433                "
434                4ccd089b28ff96da9db6c346ec114e0f
435                5b8a319f35aba624da8cf6ed4fb8a6fb
436                ",
437            ),
438            // public key
439            parse_public_key(
440                "
441                3d4017c3e843895a92b70aa74d1b7ebc
442                9c982ccf2ec4968cc0cd55f12af4660c
443                ",
444            ),
445            // message
446            [0x72].to_vec(),
447            // signature
448            parse_signature(
449                "
450                92a009a9f0d4cab8720e820b5f642540
451                a2b27b5416503f8fb3762223ebdb69da
452                085ac1e43e15996e458f3613d0f11d8c
453                387b2eaeb4302aeeb00d291612bb0c00
454                ",
455            ),
456        )
457    }
458
459    #[test]
460    fn test_codec_private_key() {
461        let private_key = parse_private_key(
462            "
463            9d61b19deffd5a60ba844af492ec2cc4
464            4449c5697b326919703bac031cae7f60
465            ",
466        );
467        let encoded = private_key.encode();
468        assert_eq!(encoded.len(), PRIVATE_KEY_LENGTH);
469        let decoded = PrivateKey::decode(encoded).unwrap();
470        assert_eq!(private_key, decoded);
471    }
472
473    #[test]
474    fn test_codec_public_key() {
475        let public_key = parse_public_key(
476            "
477            d75a980182b10ab7d54bfed3c964073a
478            0ee172f3daa62325af021a68f707511a
479            ",
480        );
481        let encoded = public_key.encode();
482        assert_eq!(encoded.len(), PUBLIC_KEY_LENGTH);
483        let decoded = PublicKey::decode(encoded).unwrap();
484        assert_eq!(public_key, decoded);
485    }
486
487    #[test]
488    fn test_codec_signature() {
489        let signature = parse_signature(
490            "
491            e5564300c360ac729086e2cc806e828a
492            84877f1eb8e5d974d873e06522490155
493            5fb8821590a33bacc61e39701cf9b46b
494            d25bf5f0595bbe24655141438e7a100b
495            ",
496        );
497        let encoded = signature.encode();
498        assert_eq!(encoded.len(), SIGNATURE_LENGTH);
499        let decoded = Signature::decode(encoded).unwrap();
500        assert_eq!(signature, decoded);
501    }
502
503    #[test]
504    fn rfc8032_test_vector_1() {
505        let (private_key, public_key, message, signature) = vector_1();
506        test_sign_and_verify(private_key, public_key, &message, signature)
507    }
508
509    // sanity check the test infra rejects bad signatures
510    #[test]
511    #[should_panic]
512    fn bad_signature() {
513        let (private_key, public_key, message, _) = vector_1();
514        let mut signer = <Ed25519 as Signer>::new(&mut OsRng);
515        let bad_signature = signer.sign(None, message.as_ref());
516        test_sign_and_verify(private_key, public_key, &message, bad_signature);
517    }
518
519    // sanity check the test infra rejects non-matching messages
520    #[test]
521    #[should_panic]
522    fn different_message() {
523        let (private_key, public_key, _, signature) = vector_1();
524        let different_message = b"this is a different message".to_vec();
525        test_sign_and_verify(private_key, public_key, &different_message, signature);
526    }
527
528    #[test]
529    fn rfc8032_test_vector_2() {
530        let (private_key, public_key, message, signature) = vector_2();
531        test_sign_and_verify(private_key, public_key, &message, signature)
532    }
533
534    #[test]
535    fn rfc8032_test_vector_3() {
536        let private_key = parse_private_key(
537            "
538            c5aa8df43f9f837bedb7442f31dcb7b1
539            66d38535076f094b85ce3a2e0b4458f7
540            ",
541        );
542        let public_key = parse_public_key(
543            "
544            fc51cd8e6218a1a38da47ed00230f058
545            0816ed13ba3303ac5deb911548908025
546            ",
547        );
548        let message: [u8; 2] = [0xaf, 0x82];
549        let signature = parse_signature(
550            "
551            6291d657deec24024827e69c3abe01a3
552            0ce548a284743a445e3680d7db5ac3ac
553            18ff9b538d16f290ae67f760984dc659
554            4a7c15e9716ed28dc027beceea1ec40a
555            ",
556        );
557        test_sign_and_verify(private_key, public_key, &message, signature)
558    }
559
560    #[test]
561    fn rfc8032_test_vector_1024() {
562        let private_key = parse_private_key(
563            "
564            f5e5767cf153319517630f226876b86c
565            8160cc583bc013744c6bf255f5cc0ee5
566            ",
567        );
568        let public_key = parse_public_key(
569            "
570            278117fc144c72340f67d0f2316e8386
571            ceffbf2b2428c9c51fef7c597f1d426e
572            ",
573        );
574        let message = commonware_utils::from_hex_formatted(
575            "
576            08b8b2b733424243760fe426a4b54908
577            632110a66c2f6591eabd3345e3e4eb98
578            fa6e264bf09efe12ee50f8f54e9f77b1
579            e355f6c50544e23fb1433ddf73be84d8
580            79de7c0046dc4996d9e773f4bc9efe57
581            38829adb26c81b37c93a1b270b20329d
582            658675fc6ea534e0810a4432826bf58c
583            941efb65d57a338bbd2e26640f89ffbc
584            1a858efcb8550ee3a5e1998bd177e93a
585            7363c344fe6b199ee5d02e82d522c4fe
586            ba15452f80288a821a579116ec6dad2b
587            3b310da903401aa62100ab5d1a36553e
588            06203b33890cc9b832f79ef80560ccb9
589            a39ce767967ed628c6ad573cb116dbef
590            efd75499da96bd68a8a97b928a8bbc10
591            3b6621fcde2beca1231d206be6cd9ec7
592            aff6f6c94fcd7204ed3455c68c83f4a4
593            1da4af2b74ef5c53f1d8ac70bdcb7ed1
594            85ce81bd84359d44254d95629e9855a9
595            4a7c1958d1f8ada5d0532ed8a5aa3fb2
596            d17ba70eb6248e594e1a2297acbbb39d
597            502f1a8c6eb6f1ce22b3de1a1f40cc24
598            554119a831a9aad6079cad88425de6bd
599            e1a9187ebb6092cf67bf2b13fd65f270
600            88d78b7e883c8759d2c4f5c65adb7553
601            878ad575f9fad878e80a0c9ba63bcbcc
602            2732e69485bbc9c90bfbd62481d9089b
603            eccf80cfe2df16a2cf65bd92dd597b07
604            07e0917af48bbb75fed413d238f5555a
605            7a569d80c3414a8d0859dc65a46128ba
606            b27af87a71314f318c782b23ebfe808b
607            82b0ce26401d2e22f04d83d1255dc51a
608            ddd3b75a2b1ae0784504df543af8969b
609            e3ea7082ff7fc9888c144da2af58429e
610            c96031dbcad3dad9af0dcbaaaf268cb8
611            fcffead94f3c7ca495e056a9b47acdb7
612            51fb73e666c6c655ade8297297d07ad1
613            ba5e43f1bca32301651339e22904cc8c
614            42f58c30c04aafdb038dda0847dd988d
615            cda6f3bfd15c4b4c4525004aa06eeff8
616            ca61783aacec57fb3d1f92b0fe2fd1a8
617            5f6724517b65e614ad6808d6f6ee34df
618            f7310fdc82aebfd904b01e1dc54b2927
619            094b2db68d6f903b68401adebf5a7e08
620            d78ff4ef5d63653a65040cf9bfd4aca7
621            984a74d37145986780fc0b16ac451649
622            de6188a7dbdf191f64b5fc5e2ab47b57
623            f7f7276cd419c17a3ca8e1b939ae49e4
624            88acba6b965610b5480109c8b17b80e1
625            b7b750dfc7598d5d5011fd2dcc5600a3
626            2ef5b52a1ecc820e308aa342721aac09
627            43bf6686b64b2579376504ccc493d97e
628            6aed3fb0f9cd71a43dd497f01f17c0e2
629            cb3797aa2a2f256656168e6c496afc5f
630            b93246f6b1116398a346f1a641f3b041
631            e989f7914f90cc2c7fff357876e506b5
632            0d334ba77c225bc307ba537152f3f161
633            0e4eafe595f6d9d90d11faa933a15ef1
634            369546868a7f3a45a96768d40fd9d034
635            12c091c6315cf4fde7cb68606937380d
636            b2eaaa707b4c4185c32eddcdd306705e
637            4dc1ffc872eeee475a64dfac86aba41c
638            0618983f8741c5ef68d3a101e8a3b8ca
639            c60c905c15fc910840b94c00a0b9d0
640            ",
641        )
642        .unwrap();
643        let signature = parse_signature(
644            "
645            0aab4c900501b3e24d7cdf4663326a3a
646            87df5e4843b2cbdb67cbf6e460fec350
647            aa5371b1508f9f4528ecea23c436d94b
648            5e8fcd4f681e30a6ac00a9704a188a03
649            ",
650        );
651        test_sign_and_verify(private_key, public_key, &message, signature)
652    }
653
654    #[test]
655    fn rfc8032_test_vector_sha() {
656        let private_key = commonware_utils::from_hex_formatted(
657            "
658            833fe62409237b9d62ec77587520911e
659            9a759cec1d19755b7da901b96dca3d42
660            ",
661        )
662        .unwrap();
663        let public_key = commonware_utils::from_hex_formatted(
664            "
665            ec172b93ad5e563bf4932c70e1245034
666            c35467ef2efd4d64ebf819683467e2bf
667            ",
668        )
669        .unwrap();
670        let message = commonware_utils::from_hex_formatted(
671            "
672            ddaf35a193617abacc417349ae204131
673            12e6fa4e89a97ea20a9eeee64b55d39a
674            2192992a274fc1a836ba3c23a3feebbd
675            454d4423643ce80e2a9ac94fa54ca49f
676            ",
677        )
678        .unwrap();
679        let signature = commonware_utils::from_hex_formatted(
680            "
681            dc2a4459e7369633a52b1bf277839a00
682            201009a3efbf3ecb69bea2186c26b589
683            09351fc9ac90b3ecfdfbc7c66431e030
684            3dca179c138ac17ad9bef1177331a704
685            ",
686        )
687        .unwrap();
688        test_sign_and_verify(
689            PrivateKey::decode(private_key.as_ref()).unwrap(),
690            PublicKey::decode(public_key.as_ref()).unwrap(),
691            &message,
692            Signature::decode(signature.as_ref()).unwrap(),
693        )
694    }
695
696    #[test]
697    fn batch_verify_valid() {
698        let v1 = vector_1();
699        let v2 = vector_2();
700        let mut batch = Ed25519Batch::new();
701        assert!(batch.add(None, &v1.2, &v1.1, &v1.3));
702        assert!(batch.add(None, &v2.2, &v2.1, &v2.3));
703        assert!(batch.verify(&mut rand::thread_rng()));
704    }
705
706    #[test]
707    fn batch_verify_invalid() {
708        let v1 = vector_1();
709        let v2 = vector_2();
710        let mut bad_signature = v2.3.to_vec();
711        bad_signature[3] = 0xff;
712
713        let mut batch = Ed25519Batch::new();
714        assert!(batch.add(None, &v1.2, &v1.1, &v1.3));
715        assert!(batch.add(
716            None,
717            &v2.2,
718            &v2.1,
719            &Signature::decode(bad_signature.as_ref()).unwrap()
720        ));
721        assert!(!batch.verify(&mut rand::thread_rng()));
722    }
723}
commonware_cryptography/ed25519/scheme.rs

commonware_cryptography/ed25519/
scheme.rs
