sui_sdk_types/crypto/
zklogin.rs

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
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
use super::SimpleSignature;
use crate::checkpoint::EpochId;
use crate::u256::U256;

/// A zklogin authenticator
///
/// # BCS
///
/// The BCS serialized form for this type is defined by the following ABNF:
///
/// ```text
/// zklogin-bcs = bytes             ; contents are defined by <zklogin-authenticator>
/// zklogin     = zklogin-flag
///               zklogin-inputs
///               u64               ; max epoch
///               simple-signature    
/// ```
///
/// Note: Due to historical reasons, signatures are serialized slightly different from the majority
/// of the types in Sui. In particular if a signature is ever embedded in another structure it
/// generally is serialized as `bytes` meaning it has a length prefix that defines the length of
/// the completely serialized signature.
#[derive(Debug, Clone, PartialEq, Eq)]
#[cfg_attr(feature = "proptest", derive(test_strategy::Arbitrary))]
pub struct ZkLoginAuthenticator {
    /// Zklogin proof and inputs required to perform proof verification.
    pub inputs: ZkLoginInputs,

    /// Maximum epoch for which the proof is valid.
    pub max_epoch: EpochId,

    /// User signature with the pubkey attested to by the provided proof.
    pub signature: SimpleSignature,
}

/// A zklogin groth16 proof and the required inputs to perform proof verification.
///
/// # BCS
///
/// The BCS serialized form for this type is defined by the following ABNF:
///
/// ```text
/// zklogin-inputs = zklogin-proof
///                  zklogin-claim
///                  string              ; base64url-unpadded encoded JwtHeader
///                  bn254-field-element ; address_seed
/// ```
#[derive(Debug, Clone, PartialEq, Eq)]
#[cfg_attr(
    feature = "serde",
    derive(serde_derive::Serialize, serde_derive::Deserialize)
)]
#[cfg_attr(feature = "proptest", derive(test_strategy::Arbitrary))]
pub struct ZkLoginInputs {
    pub proof_points: ZkLoginProof,
    pub iss_base64_details: ZkloginClaim,
    pub header_base64: String,
    pub address_seed: Bn254FieldElement,
}

/// A claim of the iss in a zklogin proof
///
/// # BCS
///
/// The BCS serialized form for this type is defined by the following ABNF:
///
/// ```text
/// zklogin-claim = string u8
/// ```
#[derive(Debug, Clone, PartialEq, Eq)]
#[cfg_attr(
    feature = "serde",
    derive(serde_derive::Serialize, serde_derive::Deserialize)
)]
#[cfg_attr(feature = "proptest", derive(test_strategy::Arbitrary))]
pub struct ZkloginClaim {
    pub value: String,
    pub index_mod_4: u8,
}

/// A zklogin groth16 proof
///
/// # BCS
///
/// The BCS serialized form for this type is defined by the following ABNF:
///
/// ```text
/// zklogin-proof = circom-g1 circom-g2 circom-g1
/// ```
#[derive(Debug, Clone, PartialEq, Eq)]
#[cfg_attr(
    feature = "serde",
    derive(serde_derive::Serialize, serde_derive::Deserialize)
)]
#[cfg_attr(feature = "proptest", derive(test_strategy::Arbitrary))]
pub struct ZkLoginProof {
    pub a: CircomG1,
    pub b: CircomG2,
    pub c: CircomG1,
}

/// A G1 point
///
/// This represents the canonical decimal representation of the projective coordinates in Fq.
///
/// # BCS
///
/// The BCS serialized form for this type is defined by the following ABNF:
///
/// ```text
/// circom-g1 = %x03 3(bn254-field-element)
/// ```
#[derive(Clone, Debug, PartialEq, Eq)]
#[cfg_attr(feature = "proptest", derive(test_strategy::Arbitrary))]
pub struct CircomG1(pub [Bn254FieldElement; 3]);

/// A G2 point
///
/// This represents the canonical decimal representation of the coefficients of the projective
/// coordinates in Fq2.
///
/// # BCS
///
/// The BCS serialized form for this type is defined by the following ABNF:
///
/// ```text
/// circom-g2 = %x03 3(%x02 2(bn254-field-element))
/// ```
#[derive(Clone, Debug, PartialEq, Eq)]
#[cfg_attr(feature = "proptest", derive(test_strategy::Arbitrary))]
pub struct CircomG2(pub [[Bn254FieldElement; 2]; 3]);

/// Public Key equivalent for Zklogin authenticators
///
/// A `ZkLoginPublicIdentifier` is the equivalent of a public key for other account authenticators,
/// and contains the information required to derive the onchain account [`Address`] for a Zklogin
/// authenticator.
///
/// ## Note
///
/// Due to a historical bug that was introduced in the Sui Typescript SDK when the zklogin
/// authenticator was first introduced, there are now possibly two "valid" addresses for each
/// zklogin authenticator depending on the bit-pattern of the `address_seed` value.
///
/// The original bug incorrectly derived a zklogin's address by stripping any leading
/// zero-bytes that could have been present in the 32-byte length `address_seed` value prior to
/// hashing, leading to a different derived address. This incorrectly derived address was
/// presented to users of various wallets, leading them to sending funds to these addresses
/// that they couldn't access. Instead of letting these users lose any assets that were sent to
/// these addresses, the Sui network decided to change the protocol to allow for a zklogin
/// authenticator who's `address_seed` value had leading zero-bytes be authorized to sign for
/// both the addresses derived from both the unpadded and padded `address_seed` value.
///
/// # BCS
///
/// The BCS serialized form for this type is defined by the following ABNF:
///
/// ```text
/// zklogin-public-identifier-bcs = bytes ; where the contents are defined by
///                                       ; <zklogin-public-identifier>
///
/// zklogin-public-identifier = zklogin-public-identifier-iss
///                             address-seed
///
/// zklogin-public-identifier-unpadded = zklogin-public-identifier-iss
///                                      address-seed-unpadded
///
/// ; The iss, or issuer, is a utf8 string that is less than 255 bytes long
/// ; and is serialized with the iss's length in bytes as a u8 followed by
/// ; the bytes of the iss
/// zklogin-public-identifier-iss = u8 *255(OCTET)
///
/// ; A Bn254FieldElement serialized as a 32-byte big-endian value
/// address-seed = 32(OCTET)
///
/// ; A Bn254FieldElement serialized as a 32-byte big-endian value
/// ; with any leading zero bytes stripped
/// address-seed-unpadded = %x00 / %x01-ff *31(OCTET)
/// ```
///
/// [`Address`]: crate::Address
#[derive(Clone, Debug, PartialEq, Eq)]
#[cfg_attr(feature = "proptest", derive(test_strategy::Arbitrary))]
pub struct ZkLoginPublicIdentifier {
    iss: String,
    address_seed: Bn254FieldElement,
}

impl ZkLoginPublicIdentifier {
    pub fn new(iss: String, address_seed: Bn254FieldElement) -> Option<Self> {
        if iss.len() > 255 {
            None
        } else {
            Some(Self { iss, address_seed })
        }
    }

    pub fn iss(&self) -> &str {
        &self.iss
    }

    pub fn address_seed(&self) -> &Bn254FieldElement {
        &self.address_seed
    }
}

/// A JSON Web Key
///
/// Struct that contains info for a JWK. A list of them for different kids can
/// be retrieved from the JWK endpoint (e.g. <https://www.googleapis.com/oauth2/v3/certs>).
/// The JWK is used to verify the JWT token.
///
/// # BCS
///
/// The BCS serialized form for this type is defined by the following ABNF:
///
/// ```text
/// jwk = string string string string
/// ```
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
#[cfg_attr(
    feature = "serde",
    derive(serde_derive::Serialize, serde_derive::Deserialize)
)]
#[cfg_attr(feature = "proptest", derive(test_strategy::Arbitrary))]
pub struct Jwk {
    /// Key type parameter, <https://datatracker.ietf.org/doc/html/rfc7517#section-4.1>
    pub kty: String,

    /// RSA public exponent, <https://datatracker.ietf.org/doc/html/rfc7517#section-9.3>
    pub e: String,

    /// RSA modulus, <https://datatracker.ietf.org/doc/html/rfc7517#section-9.3>
    pub n: String,

    /// Algorithm parameter, <https://datatracker.ietf.org/doc/html/rfc7517#section-4.4>
    pub alg: String,
}

/// Key to uniquely identify a JWK
///
/// # BCS
///
/// The BCS serialized form for this type is defined by the following ABNF:
///
/// ```text
/// jwk-id = string string
/// ```
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
#[cfg_attr(
    feature = "serde",
    derive(serde_derive::Serialize, serde_derive::Deserialize)
)]
#[cfg_attr(feature = "proptest", derive(test_strategy::Arbitrary))]
pub struct JwkId {
    /// The issuer or identity of the OIDC provider.
    pub iss: String,

    /// A key id use to uniquely identify a key from an OIDC provider.
    pub kid: String,
}

/// A point on the BN254 elliptic curve.
///
/// This is a 32-byte, or 256-bit, value that is generally represented as radix10 when a
/// human-readable display format is needed, and is represented as a 32-byte big-endian value while
/// in memory.
///
/// # BCS
///
/// The BCS serialized form for this type is defined by the following ABNF:
///
/// ```text
/// bn254-field-element = *DIGIT ; which is then interpreted as a radix10 encoded 32-byte value
/// ```
#[derive(Clone, Debug, Default, PartialEq, Eq)]
#[cfg_attr(feature = "proptest", derive(test_strategy::Arbitrary))]
pub struct Bn254FieldElement([u8; 32]);

impl Bn254FieldElement {
    pub const fn new(bytes: [u8; 32]) -> Self {
        Self(bytes)
    }

    pub const fn from_str_radix_10(s: &str) -> Result<Self, Bn254FieldElementParseError> {
        let u256 = match U256::from_str_radix(s, 10) {
            Ok(u256) => u256,
            Err(e) => return Err(Bn254FieldElementParseError(e)),
        };
        let be = u256.to_be();
        Ok(Self(*be.digits()))
    }

    pub fn unpadded(&self) -> &[u8] {
        let mut buf = self.0.as_slice();

        while !buf.is_empty() && buf[0] == 0 {
            buf = &buf[1..];
        }

        // If the value is '0' then just return a slice of length 1 of the final byte
        if buf.is_empty() {
            &self.0[31..]
        } else {
            buf
        }
    }

    pub fn padded(&self) -> &[u8] {
        &self.0
    }
}

impl std::fmt::Display for Bn254FieldElement {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        let u256 = U256::from_be(U256::from_digits(self.0));
        let radix10 = u256.to_str_radix(10);
        f.write_str(&radix10)
    }
}

#[derive(Debug)]
pub struct Bn254FieldElementParseError(bnum::errors::ParseIntError);

impl std::fmt::Display for Bn254FieldElementParseError {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(f, "unable to parse radix10 encoded value {}", self.0)
    }
}

impl std::error::Error for Bn254FieldElementParseError {}

impl std::str::FromStr for Bn254FieldElement {
    type Err = Bn254FieldElementParseError;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        let u256 = U256::from_str_radix(s, 10).map_err(Bn254FieldElementParseError)?;
        let be = u256.to_be();
        Ok(Self(*be.digits()))
    }
}

#[cfg(test)]
mod test {
    use super::Bn254FieldElement;
    use num_bigint::BigUint;
    use proptest::prelude::*;
    use std::str::FromStr;
    use test_strategy::proptest;

    #[cfg(target_arch = "wasm32")]
    use wasm_bindgen_test::wasm_bindgen_test as test;

    #[test]
    fn unpadded_slice() {
        let seed = Bn254FieldElement([0; 32]);
        let zero: [u8; 1] = [0];
        assert_eq!(seed.unpadded(), zero.as_slice());

        let mut seed = Bn254FieldElement([1; 32]);
        seed.0[0] = 0;
        assert_eq!(seed.unpadded(), [1; 31].as_slice());
    }

    #[proptest]
    fn dont_crash_on_large_inputs(
        #[strategy(proptest::collection::vec(any::<u8>(), 33..1024))] bytes: Vec<u8>,
    ) {
        let big_int = BigUint::from_bytes_be(&bytes);
        let radix10 = big_int.to_str_radix(10);

        // doesn't crash
        let _ = Bn254FieldElement::from_str(&radix10);
    }

    #[proptest]
    fn valid_address_seeds(
        #[strategy(proptest::collection::vec(any::<u8>(), 1..=32))] bytes: Vec<u8>,
    ) {
        let big_int = BigUint::from_bytes_be(&bytes);
        let radix10 = big_int.to_str_radix(10);

        let seed = Bn254FieldElement::from_str(&radix10).unwrap();
        assert_eq!(radix10, seed.to_string());
        // Ensure unpadded doesn't crash
        seed.unpadded();
    }
}

#[cfg(feature = "serde")]
#[cfg_attr(doc_cfg, doc(cfg(feature = "serde")))]
mod serialization {
    use crate::SignatureScheme;

    use super::*;
    use serde::Deserialize;
    use serde::Deserializer;
    use serde::Serialize;
    use serde::Serializer;
    use serde_with::Bytes;
    use serde_with::DeserializeAs;
    use serde_with::SerializeAs;
    use std::borrow::Cow;

    // Serialized format is: iss_bytes_len || iss_bytes || padded_32_byte_address_seed.
    impl Serialize for ZkLoginPublicIdentifier {
        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
        where
            S: Serializer,
        {
            if serializer.is_human_readable() {
                #[derive(serde_derive::Serialize)]
                struct Readable<'a> {
                    iss: &'a str,
                    address_seed: &'a Bn254FieldElement,
                }
                let readable = Readable {
                    iss: &self.iss,
                    address_seed: &self.address_seed,
                };
                readable.serialize(serializer)
            } else {
                let mut buf = Vec::new();
                let iss_bytes = self.iss.as_bytes();
                buf.push(iss_bytes.len() as u8);
                buf.extend(iss_bytes);

                buf.extend(&self.address_seed.0);

                serializer.serialize_bytes(&buf)
            }
        }
    }

    impl<'de> Deserialize<'de> for ZkLoginPublicIdentifier {
        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
        where
            D: Deserializer<'de>,
        {
            if deserializer.is_human_readable() {
                #[derive(serde_derive::Deserialize)]
                struct Readable {
                    iss: String,
                    address_seed: Bn254FieldElement,
                }

                let Readable { iss, address_seed } = Deserialize::deserialize(deserializer)?;
                Self::new(iss, address_seed)
                    .ok_or_else(|| serde::de::Error::custom("invalid zklogin public identifier"))
            } else {
                let bytes: Cow<'de, [u8]> = Bytes::deserialize_as(deserializer)?;
                let iss_len = *bytes
                    .first()
                    .ok_or_else(|| serde::de::Error::custom("invalid zklogin public identifier"))?;
                let iss_bytes = bytes
                    .get(1..(1 + iss_len as usize))
                    .ok_or_else(|| serde::de::Error::custom("invalid zklogin public identifier"))?;
                let iss = std::str::from_utf8(iss_bytes).map_err(serde::de::Error::custom)?;
                let address_seed_bytes = bytes
                    .get((1 + iss_len as usize)..)
                    .ok_or_else(|| serde::de::Error::custom("invalid zklogin public identifier"))?;

                let address_seed = <[u8; 32]>::try_from(address_seed_bytes)
                    .map_err(serde::de::Error::custom)
                    .map(Bn254FieldElement)?;

                Self::new(iss.into(), address_seed)
                    .ok_or_else(|| serde::de::Error::custom("invalid zklogin public identifier"))
            }
        }
    }

    #[derive(serde_derive::Serialize)]
    struct AuthenticatorRef<'a> {
        inputs: &'a ZkLoginInputs,
        #[cfg_attr(feature = "serde", serde(with = "crate::_serde::ReadableDisplay"))]
        max_epoch: EpochId,
        signature: &'a SimpleSignature,
    }

    #[derive(serde_derive::Deserialize)]
    struct Authenticator {
        inputs: ZkLoginInputs,
        #[cfg_attr(feature = "serde", serde(with = "crate::_serde::ReadableDisplay"))]
        max_epoch: EpochId,
        signature: SimpleSignature,
    }

    impl Serialize for ZkLoginAuthenticator {
        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
        where
            S: Serializer,
        {
            if serializer.is_human_readable() {
                let authenticator_ref = AuthenticatorRef {
                    inputs: &self.inputs,
                    max_epoch: self.max_epoch,
                    signature: &self.signature,
                };

                authenticator_ref.serialize(serializer)
            } else {
                let bytes = self.to_bytes();
                serializer.serialize_bytes(&bytes)
            }
        }
    }

    impl<'de> Deserialize<'de> for ZkLoginAuthenticator {
        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
        where
            D: Deserializer<'de>,
        {
            if deserializer.is_human_readable() {
                let Authenticator {
                    inputs,
                    max_epoch,
                    signature,
                } = Authenticator::deserialize(deserializer)?;
                Ok(Self {
                    inputs,
                    max_epoch,
                    signature,
                })
            } else {
                let bytes: Cow<'de, [u8]> = Bytes::deserialize_as(deserializer)?;
                Self::from_serialized_bytes(bytes)
            }
        }
    }

    impl ZkLoginAuthenticator {
        pub(crate) fn to_bytes(&self) -> Vec<u8> {
            let authenticator_ref = AuthenticatorRef {
                inputs: &self.inputs,
                max_epoch: self.max_epoch,
                signature: &self.signature,
            };

            let mut buf = Vec::new();
            buf.push(SignatureScheme::ZkLogin as u8);

            bcs::serialize_into(&mut buf, &authenticator_ref).expect("serialization cannot fail");
            buf
        }

        pub(crate) fn from_serialized_bytes<T: AsRef<[u8]>, E: serde::de::Error>(
            bytes: T,
        ) -> Result<Self, E> {
            let bytes = bytes.as_ref();
            let flag = SignatureScheme::from_byte(
                *bytes
                    .first()
                    .ok_or_else(|| serde::de::Error::custom("missing signature scheme falg"))?,
            )
            .map_err(serde::de::Error::custom)?;
            if flag != SignatureScheme::ZkLogin {
                return Err(serde::de::Error::custom("invalid zklogin flag"));
            }
            let bcs_bytes = &bytes[1..];

            let Authenticator {
                inputs,
                max_epoch,
                signature,
            } = bcs::from_bytes(bcs_bytes).map_err(serde::de::Error::custom)?;
            Ok(Self {
                inputs,
                max_epoch,
                signature,
            })
        }
    }

    // AddressSeed's serialized format is as a radix10 encoded string
    impl Serialize for Bn254FieldElement {
        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
        where
            S: serde::Serializer,
        {
            serde_with::DisplayFromStr::serialize_as(self, serializer)
        }
    }

    impl<'de> Deserialize<'de> for Bn254FieldElement {
        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
        where
            D: Deserializer<'de>,
        {
            serde_with::DisplayFromStr::deserialize_as(deserializer)
        }
    }

    impl Serialize for CircomG1 {
        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
        where
            S: serde::Serializer,
        {
            use serde::ser::SerializeSeq;
            let mut seq = serializer.serialize_seq(Some(self.0.len()))?;
            for element in &self.0 {
                seq.serialize_element(element)?;
            }
            seq.end()
        }
    }

    impl<'de> Deserialize<'de> for CircomG1 {
        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
        where
            D: Deserializer<'de>,
        {
            let inner = <Vec<_>>::deserialize(deserializer)?;
            Ok(Self(inner.try_into().map_err(|_| {
                serde::de::Error::custom("expected array of length 3")
            })?))
        }
    }

    impl Serialize for CircomG2 {
        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
        where
            S: serde::Serializer,
        {
            use serde::ser::SerializeSeq;

            struct Inner<'a>(&'a [Bn254FieldElement; 2]);

            impl Serialize for Inner<'_> {
                fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
                where
                    S: serde::Serializer,
                {
                    let mut seq = serializer.serialize_seq(Some(self.0.len()))?;
                    for element in self.0 {
                        seq.serialize_element(element)?;
                    }
                    seq.end()
                }
            }

            let mut seq = serializer.serialize_seq(Some(self.0.len()))?;
            for element in &self.0 {
                seq.serialize_element(&Inner(element))?;
            }
            seq.end()
        }
    }

    impl<'de> Deserialize<'de> for CircomG2 {
        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
        where
            D: Deserializer<'de>,
        {
            let vecs = <Vec<Vec<Bn254FieldElement>>>::deserialize(deserializer)?;
            let mut inner: [[Bn254FieldElement; 2]; 3] = Default::default();

            if vecs.len() != 3 {
                return Err(serde::de::Error::custom(
                    "vector of three vectors each being a vector of two strings",
                ));
            }

            for (i, v) in vecs.into_iter().enumerate() {
                if v.len() != 2 {
                    return Err(serde::de::Error::custom(
                        "vector of three vectors each being a vector of two strings",
                    ));
                }

                for (j, point) in v.into_iter().enumerate() {
                    inner[i][j] = point;
                }
            }

            Ok(Self(inner))
        }
    }
}