solana_secp256r1_program/
lib.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
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
//! Instructions for the [secp256r1 native program][np].
//! [np]: https://docs.solana.com/developing/runtime-facilities/programs#secp256r1-program
//!
//! Note on Signature Malleability:
//! This precompile requires low-S values in signatures (s <= half_curve_order) to prevent signature malleability.
//! Signature malleability means that for a valid signature (r,s), (r, order-s) is also valid for the
//! same message and public key.
//!
//! This property can be problematic for developers who assume each signature is unique. Without enforcing
//! low-S values, the same message and key can produce two different valid signatures, potentially breaking
//! replay protection schemes that rely on signature uniqueness.
solana_pubkey::declare_id!("Secp256r1SigVerify1111111111111111111111111");

use bytemuck::{Pod, Zeroable};

#[derive(Default, Debug, Copy, Clone, Zeroable, Pod, Eq, PartialEq)]
#[repr(C)]
pub struct Secp256r1SignatureOffsets {
    /// Offset to compact secp256r1 signature of 64 bytes
    pub signature_offset: u16,

    /// Instruction index where the signature can be found
    pub signature_instruction_index: u16,

    /// Offset to compressed public key of 33 bytes
    pub public_key_offset: u16,

    /// Instruction index where the public key can be found
    pub public_key_instruction_index: u16,

    /// Offset to the start of message data
    pub message_data_offset: u16,

    /// Size of message data in bytes
    pub message_data_size: u16,

    /// Instruction index where the message data can be found
    pub message_instruction_index: u16,
}

#[cfg(all(not(target_arch = "wasm32"), not(target_os = "solana")))]
mod target_arch {
    use {
        crate::Secp256r1SignatureOffsets,
        bytemuck::bytes_of,
        openssl::{
            bn::{BigNum, BigNumContext},
            ec::{EcGroup, EcKey, EcPoint},
            ecdsa::EcdsaSig,
            nid::Nid,
            pkey::{PKey, Private},
            sign::{Signer, Verifier},
        },
        solana_feature_set::FeatureSet,
        solana_instruction::Instruction,
        solana_precompile_error::PrecompileError,
    };

    pub const COMPRESSED_PUBKEY_SERIALIZED_SIZE: usize = 33;
    pub const SIGNATURE_SERIALIZED_SIZE: usize = 64;
    pub const SIGNATURE_OFFSETS_SERIALIZED_SIZE: usize = 14;
    pub const SIGNATURE_OFFSETS_START: usize = 2;
    pub const DATA_START: usize = SIGNATURE_OFFSETS_SERIALIZED_SIZE + SIGNATURE_OFFSETS_START;

    // Order as defined in SEC2: 2.7.2 Recommended Parameters secp256r1
    pub const SECP256R1_ORDER: [u8; FIELD_SIZE] = [
        0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
        0xFF, 0xBC, 0xE6, 0xFA, 0xAD, 0xA7, 0x17, 0x9E, 0x84, 0xF3, 0xB9, 0xCA, 0xC2, 0xFC, 0x63,
        0x25, 0x51,
    ];

    // Computed SECP256R1_ORDER - 1
    pub const SECP256R1_ORDER_MINUS_ONE: [u8; FIELD_SIZE] = [
        0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
        0xFF, 0xBC, 0xE6, 0xFA, 0xAD, 0xA7, 0x17, 0x9E, 0x84, 0xF3, 0xB9, 0xCA, 0xC2, 0xFC, 0x63,
        0x25, 0x50,
    ];

    // Computed half order
    const SECP256R1_HALF_ORDER: [u8; FIELD_SIZE] = [
        0x7F, 0xFF, 0xFF, 0xFF, 0x80, 0x00, 0x00, 0x00, 0x7F, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
        0xFF, 0xDE, 0x73, 0x7D, 0x56, 0xD3, 0x8B, 0xCF, 0x42, 0x79, 0xDC, 0xE5, 0x61, 0x7E, 0x31,
        0x92, 0xA8,
    ];
    // Field size in bytes
    const FIELD_SIZE: usize = 32;

    pub fn new_secp256r1_instruction(
        message: &[u8],
        signing_key: EcKey<Private>,
    ) -> Result<Instruction, Box<dyn std::error::Error>> {
        let group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1)?;
        if signing_key.group().curve_name() != Some(Nid::X9_62_PRIME256V1) {
            return Err(("Signing key must be on the secp256r1 curve".to_string()).into());
        }

        let mut ctx = BigNumContext::new()?;
        let pubkey = signing_key.public_key().to_bytes(
            &group,
            openssl::ec::PointConversionForm::COMPRESSED,
            &mut ctx,
        )?;

        let signing_key_pkey = PKey::from_ec_key(signing_key)?;

        let mut signer = Signer::new(openssl::hash::MessageDigest::sha256(), &signing_key_pkey)?;
        signer.update(message)?;
        let signature = signer.sign_to_vec()?;

        let ecdsa_sig = EcdsaSig::from_der(&signature)?;
        let r = ecdsa_sig.r().to_vec();
        let s = ecdsa_sig.s().to_vec();
        let mut signature = vec![0u8; SIGNATURE_SERIALIZED_SIZE];

        // Incase of an r or s value of 31 bytes we need to pad it to 32 bytes
        let mut padded_r = vec![0u8; FIELD_SIZE];
        let mut padded_s = vec![0u8; FIELD_SIZE];
        padded_r[FIELD_SIZE.saturating_sub(r.len())..].copy_from_slice(&r);
        padded_s[FIELD_SIZE.saturating_sub(s.len())..].copy_from_slice(&s);

        signature[..FIELD_SIZE].copy_from_slice(&padded_r);
        signature[FIELD_SIZE..].copy_from_slice(&padded_s);

        // Check if s > half_order, if so, compute s = order - s
        let s_bignum = BigNum::from_slice(&s)?;
        let half_order = BigNum::from_slice(&SECP256R1_HALF_ORDER)?;
        let order = BigNum::from_slice(&SECP256R1_ORDER)?;
        if s_bignum > half_order {
            let mut new_s = BigNum::new()?;
            new_s.checked_sub(&order, &s_bignum)?;
            let new_s_bytes = new_s.to_vec();

            // Incase the new s value is 31 bytes we need to pad it to 32 bytes
            let mut new_padded_s = vec![0u8; FIELD_SIZE];
            new_padded_s[FIELD_SIZE.saturating_sub(new_s_bytes.len())..]
                .copy_from_slice(&new_s_bytes);

            signature[FIELD_SIZE..].copy_from_slice(&new_padded_s);
        }

        assert_eq!(pubkey.len(), COMPRESSED_PUBKEY_SERIALIZED_SIZE);
        assert_eq!(signature.len(), SIGNATURE_SERIALIZED_SIZE);

        let mut instruction_data = Vec::with_capacity(
            DATA_START
                .saturating_add(SIGNATURE_SERIALIZED_SIZE)
                .saturating_add(COMPRESSED_PUBKEY_SERIALIZED_SIZE)
                .saturating_add(message.len()),
        );

        let num_signatures: u8 = 1;
        let public_key_offset = DATA_START;
        let signature_offset = public_key_offset.saturating_add(COMPRESSED_PUBKEY_SERIALIZED_SIZE);
        let message_data_offset = signature_offset.saturating_add(SIGNATURE_SERIALIZED_SIZE);

        instruction_data.extend_from_slice(bytes_of(&[num_signatures, 0]));

        let offsets = Secp256r1SignatureOffsets {
            signature_offset: signature_offset as u16,
            signature_instruction_index: u16::MAX,
            public_key_offset: public_key_offset as u16,
            public_key_instruction_index: u16::MAX,
            message_data_offset: message_data_offset as u16,
            message_data_size: message.len() as u16,
            message_instruction_index: u16::MAX,
        };

        instruction_data.extend_from_slice(bytes_of(&offsets));
        instruction_data.extend_from_slice(&pubkey);
        instruction_data.extend_from_slice(&signature);
        instruction_data.extend_from_slice(message);

        Ok(Instruction {
            program_id: crate::id(),
            accounts: vec![],
            data: instruction_data,
        })
    }

    pub fn verify(
        data: &[u8],
        instruction_datas: &[&[u8]],
        _feature_set: &FeatureSet,
    ) -> Result<(), PrecompileError> {
        if data.len() < SIGNATURE_OFFSETS_START {
            return Err(PrecompileError::InvalidInstructionDataSize);
        }
        let num_signatures = data[0] as usize;
        if num_signatures == 0 {
            return Err(PrecompileError::InvalidInstructionDataSize);
        }
        if num_signatures > 8 {
            return Err(PrecompileError::InvalidInstructionDataSize);
        }

        let expected_data_size = num_signatures
            .saturating_mul(SIGNATURE_OFFSETS_SERIALIZED_SIZE)
            .saturating_add(SIGNATURE_OFFSETS_START);

        // We do not check or use the byte at data[1]
        if data.len() < expected_data_size {
            return Err(PrecompileError::InvalidInstructionDataSize);
        }

        // Parse half order from constant
        let half_order: BigNum = BigNum::from_slice(&SECP256R1_HALF_ORDER)
            .map_err(|_| PrecompileError::InvalidSignature)?;

        // Parse order - 1 from constant
        let order_minus_one: BigNum = BigNum::from_slice(&SECP256R1_ORDER_MINUS_ONE)
            .map_err(|_| PrecompileError::InvalidSignature)?;

        // Create a BigNum for 1
        let one = BigNum::from_u32(1).map_err(|_| PrecompileError::InvalidSignature)?;

        // Define curve group
        let group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1)
            .map_err(|_| PrecompileError::InvalidSignature)?;
        let mut ctx = BigNumContext::new().map_err(|_| PrecompileError::InvalidSignature)?;

        for i in 0..num_signatures {
            let start = i
                .saturating_mul(SIGNATURE_OFFSETS_SERIALIZED_SIZE)
                .saturating_add(SIGNATURE_OFFSETS_START);
            let end = start.saturating_add(SIGNATURE_OFFSETS_SERIALIZED_SIZE);

            // bytemuck wants structures aligned
            let offsets: &Secp256r1SignatureOffsets =
                bytemuck::try_from_bytes(&data[start..end])
                    .map_err(|_| PrecompileError::InvalidDataOffsets)?;

            // Parse out signature
            let signature = get_data_slice(
                data,
                instruction_datas,
                offsets.signature_instruction_index,
                offsets.signature_offset,
                SIGNATURE_SERIALIZED_SIZE,
            )?;

            // Parse out pubkey
            let pubkey = get_data_slice(
                data,
                instruction_datas,
                offsets.public_key_instruction_index,
                offsets.public_key_offset,
                COMPRESSED_PUBKEY_SERIALIZED_SIZE,
            )?;

            // Parse out message
            let message = get_data_slice(
                data,
                instruction_datas,
                offsets.message_instruction_index,
                offsets.message_data_offset,
                offsets.message_data_size as usize,
            )?;

            let r_bignum = BigNum::from_slice(&signature[..FIELD_SIZE])
                .map_err(|_| PrecompileError::InvalidSignature)?;
            let s_bignum = BigNum::from_slice(&signature[FIELD_SIZE..])
                .map_err(|_| PrecompileError::InvalidSignature)?;

            // Check that the signature is generally in range
            let within_range = r_bignum >= one
                && r_bignum <= order_minus_one
                && s_bignum >= one
                && s_bignum <= half_order;

            if !within_range {
                return Err(PrecompileError::InvalidSignature);
            }

            // Create an ECDSA signature object from the ASN.1 integers
            let ecdsa_sig = openssl::ecdsa::EcdsaSig::from_private_components(r_bignum, s_bignum)
                .and_then(|sig| sig.to_der())
                .map_err(|_| PrecompileError::InvalidSignature)?;

            let public_key_point = EcPoint::from_bytes(&group, pubkey, &mut ctx)
                .map_err(|_| PrecompileError::InvalidPublicKey)?;
            let public_key = EcKey::from_public_key(&group, &public_key_point)
                .map_err(|_| PrecompileError::InvalidPublicKey)?;
            let public_key_as_pkey =
                PKey::from_ec_key(public_key).map_err(|_| PrecompileError::InvalidPublicKey)?;

            let mut verifier =
                Verifier::new(openssl::hash::MessageDigest::sha256(), &public_key_as_pkey)
                    .map_err(|_| PrecompileError::InvalidSignature)?;
            verifier
                .update(message)
                .map_err(|_| PrecompileError::InvalidSignature)?;

            if !verifier
                .verify(&ecdsa_sig)
                .map_err(|_| PrecompileError::InvalidSignature)?
            {
                return Err(PrecompileError::InvalidSignature);
            }
        }
        Ok(())
    }

    fn get_data_slice<'a>(
        data: &'a [u8],
        instruction_datas: &'a [&[u8]],
        instruction_index: u16,
        offset_start: u16,
        size: usize,
    ) -> Result<&'a [u8], PrecompileError> {
        let instruction = if instruction_index == u16::MAX {
            data
        } else {
            let signature_index = instruction_index as usize;
            if signature_index >= instruction_datas.len() {
                return Err(PrecompileError::InvalidDataOffsets);
            }
            instruction_datas[signature_index]
        };

        let start = offset_start as usize;
        let end = start.saturating_add(size);
        if end > instruction.len() {
            return Err(PrecompileError::InvalidDataOffsets);
        }

        Ok(&instruction[start..end])
    }

    #[cfg(test)]
    mod test {
        use {
            super::*,
            solana_feature_set::FeatureSet,
            solana_sdk::{
                hash::Hash,
                signature::{Keypair, Signer},
                transaction::Transaction,
            },
        };

        fn test_case(
            num_signatures: u16,
            offsets: &Secp256r1SignatureOffsets,
        ) -> Result<(), PrecompileError> {
            assert_eq!(
                bytemuck::bytes_of(offsets).len(),
                SIGNATURE_OFFSETS_SERIALIZED_SIZE
            );

            let mut instruction_data = vec![0u8; DATA_START];
            instruction_data[0..SIGNATURE_OFFSETS_START].copy_from_slice(bytes_of(&num_signatures));
            instruction_data[SIGNATURE_OFFSETS_START..DATA_START]
                .copy_from_slice(bytes_of(offsets));
            verify(
                &instruction_data,
                &[&[0u8; 100]],
                &FeatureSet::all_enabled(),
            )
        }

        #[test]
        fn test_invalid_offsets() {
            solana_logger::setup();

            let mut instruction_data = vec![0u8; DATA_START];
            let offsets = Secp256r1SignatureOffsets::default();
            instruction_data[0..SIGNATURE_OFFSETS_START].copy_from_slice(bytes_of(&1u16));
            instruction_data[SIGNATURE_OFFSETS_START..DATA_START]
                .copy_from_slice(bytes_of(&offsets));
            instruction_data.truncate(instruction_data.len() - 1);

            assert_eq!(
                verify(
                    &instruction_data,
                    &[&[0u8; 100]],
                    &FeatureSet::all_enabled()
                ),
                Err(PrecompileError::InvalidInstructionDataSize)
            );

            let offsets = Secp256r1SignatureOffsets {
                signature_instruction_index: 1,
                ..Secp256r1SignatureOffsets::default()
            };
            assert_eq!(
                test_case(1, &offsets),
                Err(PrecompileError::InvalidDataOffsets)
            );

            let offsets = Secp256r1SignatureOffsets {
                message_instruction_index: 1,
                ..Secp256r1SignatureOffsets::default()
            };
            assert_eq!(
                test_case(1, &offsets),
                Err(PrecompileError::InvalidDataOffsets)
            );

            let offsets = Secp256r1SignatureOffsets {
                public_key_instruction_index: 1,
                ..Secp256r1SignatureOffsets::default()
            };
            assert_eq!(
                test_case(1, &offsets),
                Err(PrecompileError::InvalidDataOffsets)
            );
        }

        #[test]
        fn test_invalid_signature_data_size() {
            solana_logger::setup();

            // Test data.len() < SIGNATURE_OFFSETS_START
            let small_data = vec![0u8; SIGNATURE_OFFSETS_START - 1];
            assert_eq!(
                verify(&small_data, &[&[]], &FeatureSet::all_enabled()),
                Err(PrecompileError::InvalidInstructionDataSize)
            );

            // Test num_signatures == 0
            let mut zero_sigs_data = vec![0u8; DATA_START];
            zero_sigs_data[0] = 0; // Set num_signatures to 0
            assert_eq!(
                verify(&zero_sigs_data, &[&[]], &FeatureSet::all_enabled()),
                Err(PrecompileError::InvalidInstructionDataSize)
            );

            // Test num_signatures > 8
            let mut too_many_sigs = vec![0u8; DATA_START];
            too_many_sigs[0] = 9; // Set num_signatures to 9
            assert_eq!(
                verify(&too_many_sigs, &[&[]], &FeatureSet::all_enabled()),
                Err(PrecompileError::InvalidInstructionDataSize)
            );
        }
        #[test]
        fn test_message_data_offsets() {
            let offsets = Secp256r1SignatureOffsets {
                message_data_offset: 99,
                message_data_size: 1,
                ..Secp256r1SignatureOffsets::default()
            };
            assert_eq!(
                test_case(1, &offsets),
                Err(PrecompileError::InvalidSignature)
            );

            let offsets = Secp256r1SignatureOffsets {
                message_data_offset: 100,
                message_data_size: 1,
                ..Secp256r1SignatureOffsets::default()
            };
            assert_eq!(
                test_case(1, &offsets),
                Err(PrecompileError::InvalidDataOffsets)
            );

            let offsets = Secp256r1SignatureOffsets {
                message_data_offset: 100,
                message_data_size: 1000,
                ..Secp256r1SignatureOffsets::default()
            };
            assert_eq!(
                test_case(1, &offsets),
                Err(PrecompileError::InvalidDataOffsets)
            );

            let offsets = Secp256r1SignatureOffsets {
                message_data_offset: u16::MAX,
                message_data_size: u16::MAX,
                ..Secp256r1SignatureOffsets::default()
            };
            assert_eq!(
                test_case(1, &offsets),
                Err(PrecompileError::InvalidDataOffsets)
            );
        }

        #[test]
        fn test_pubkey_offset() {
            let offsets = Secp256r1SignatureOffsets {
                public_key_offset: u16::MAX,
                ..Secp256r1SignatureOffsets::default()
            };
            assert_eq!(
                test_case(1, &offsets),
                Err(PrecompileError::InvalidDataOffsets)
            );

            let offsets = Secp256r1SignatureOffsets {
                public_key_offset: 100 - (COMPRESSED_PUBKEY_SERIALIZED_SIZE as u16) + 1,
                ..Secp256r1SignatureOffsets::default()
            };
            assert_eq!(
                test_case(1, &offsets),
                Err(PrecompileError::InvalidDataOffsets)
            );
        }

        #[test]
        fn test_signature_offset() {
            let offsets = Secp256r1SignatureOffsets {
                signature_offset: u16::MAX,
                ..Secp256r1SignatureOffsets::default()
            };
            assert_eq!(
                test_case(1, &offsets),
                Err(PrecompileError::InvalidDataOffsets)
            );

            let offsets = Secp256r1SignatureOffsets {
                signature_offset: 100 - (SIGNATURE_SERIALIZED_SIZE as u16) + 1,
                ..Secp256r1SignatureOffsets::default()
            };
            assert_eq!(
                test_case(1, &offsets),
                Err(PrecompileError::InvalidDataOffsets)
            );
        }

        #[test]
        fn test_secp256r1() {
            solana_logger::setup();
            let message_arr = b"hello";
            let group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1).unwrap();
            let signing_key = EcKey::generate(&group).unwrap();
            let mut instruction = new_secp256r1_instruction(message_arr, signing_key).unwrap();
            let mint_keypair = Keypair::new();
            let feature_set = FeatureSet::all_enabled();

            let tx = Transaction::new_signed_with_payer(
                &[instruction.clone()],
                Some(&mint_keypair.pubkey()),
                &[&mint_keypair],
                Hash::default(),
            );

            assert!(tx.verify_precompiles(&feature_set).is_ok());

            // The message is the last field in the instruction data so
            // changing its last byte will also change the signature validity
            let message_byte_index = instruction.data.len() - 1;
            instruction.data[message_byte_index] =
                instruction.data[message_byte_index].wrapping_add(12);
            let tx = Transaction::new_signed_with_payer(
                &[instruction.clone()],
                Some(&mint_keypair.pubkey()),
                &[&mint_keypair],
                Hash::default(),
            );

            assert!(tx.verify_precompiles(&feature_set).is_err());
        }

        #[test]
        fn test_secp256r1_high_s() {
            solana_logger::setup();
            let message_arr = b"hello";
            let group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1).unwrap();
            let signing_key = EcKey::generate(&group).unwrap();
            let mut instruction = new_secp256r1_instruction(message_arr, signing_key).unwrap();

            // To double check that the untampered low-S value signature passes
            let feature_set = FeatureSet::all_enabled();
            let tx_pass = verify(
                instruction.data.as_slice(),
                &[instruction.data.as_slice()],
                &feature_set,
            );
            assert!(tx_pass.is_ok());

            // Determine offsets at which to perform the S-value manipulation
            let public_key_offset = DATA_START;
            let signature_offset = public_key_offset + COMPRESSED_PUBKEY_SERIALIZED_SIZE;
            let s_offset = signature_offset + FIELD_SIZE;

            // Create a high S value by doing order - s
            let order = BigNum::from_slice(&SECP256R1_ORDER).unwrap();
            let current_s =
                BigNum::from_slice(&instruction.data[s_offset..s_offset + FIELD_SIZE]).unwrap();
            let mut high_s = BigNum::new().unwrap();
            high_s.checked_sub(&order, &current_s).unwrap();

            // Replace the S value in the signature with our high S
            instruction.data[s_offset..s_offset + FIELD_SIZE].copy_from_slice(&high_s.to_vec());

            // Since Transaction::verify_precompiles only returns a vague
            // `InvalidAccountIndex` error on precompile failure, we use verify()
            // here direclty to check for the specific
            // InvalidSignatureValueRange error
            let tx_fail = verify(
                instruction.data.as_slice(),
                &[instruction.data.as_slice()],
                &feature_set,
            );
            assert!(tx_fail.unwrap_err() == PrecompileError::InvalidSignature);
        }
        #[test]
        fn test_new_secp256r1_instruction_31byte_components() {
            solana_logger::setup();
            let message_arr = b"hello";
            let group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1).unwrap();
            let signing_key = EcKey::generate(&group).unwrap();

            // Keep generating signatures until we get one with a 31-byte component
            loop {
                let instruction =
                    new_secp256r1_instruction(message_arr, signing_key.clone()).unwrap();

                // Extract r and s from the signature
                let signature_offset = DATA_START + COMPRESSED_PUBKEY_SERIALIZED_SIZE;
                let r = &instruction.data[signature_offset..signature_offset + FIELD_SIZE];
                let s = &instruction.data
                    [signature_offset + FIELD_SIZE..signature_offset + 2 * FIELD_SIZE];

                // Convert to BigNum and back to get byte representation
                let r_bn = BigNum::from_slice(r).unwrap();
                let s_bn = BigNum::from_slice(s).unwrap();
                let r_bytes = r_bn.to_vec();
                let s_bytes = s_bn.to_vec();

                if r_bytes.len() == 31 || s_bytes.len() == 31 {
                    // Once found, verify the signature and break out of the loop
                    let mint_keypair = Keypair::new();
                    let tx = Transaction::new_signed_with_payer(
                        &[instruction],
                        Some(&mint_keypair.pubkey()),
                        &[&mint_keypair],
                        Hash::default(),
                    );

                    let feature_set = FeatureSet::all_enabled();
                    assert!(tx.verify_precompiles(&feature_set).is_ok());
                    break;
                }
            }
        }

        #[test]
        fn test_new_secp256r1_instruction_signing_key() {
            solana_logger::setup();
            let message_arr = b"hello";
            let group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1).unwrap();
            let signing_key = EcKey::generate(&group).unwrap();
            assert!(new_secp256r1_instruction(message_arr, signing_key).is_ok());

            let incorrect_group = EcGroup::from_curve_name(Nid::X9_62_PRIME192V1).unwrap();
            let incorrect_key = EcKey::generate(&incorrect_group).unwrap();
            assert!(new_secp256r1_instruction(message_arr, incorrect_key).is_err());
        }
        #[test]
        fn test_secp256r1_order() {
            let group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1).unwrap();
            let mut ctx = BigNumContext::new().unwrap();
            let mut openssl_order = BigNum::new().unwrap();
            group.order(&mut openssl_order, &mut ctx).unwrap();

            let our_order = BigNum::from_slice(&SECP256R1_ORDER).unwrap();
            assert_eq!(our_order, openssl_order);
        }

        #[test]
        fn test_secp256r1_order_minus_one() {
            let group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1).unwrap();
            let mut ctx = BigNumContext::new().unwrap();
            let mut openssl_order = BigNum::new().unwrap();
            group.order(&mut openssl_order, &mut ctx).unwrap();

            let mut expected_order_minus_one = BigNum::new().unwrap();
            expected_order_minus_one
                .checked_sub(&openssl_order, &BigNum::from_u32(1).unwrap())
                .unwrap();

            let our_order_minus_one = BigNum::from_slice(&SECP256R1_ORDER_MINUS_ONE).unwrap();
            assert_eq!(our_order_minus_one, expected_order_minus_one);
        }

        #[test]
        fn test_secp256r1_half_order() {
            // Get the secp256r1 curve group
            let group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1).unwrap();

            // Get the order from OpenSSL
            let mut ctx = BigNumContext::new().unwrap();
            let mut openssl_order = BigNum::new().unwrap();
            group.order(&mut openssl_order, &mut ctx).unwrap();

            // Calculate half order
            let mut calculated_half_order = BigNum::new().unwrap();
            let two = BigNum::from_u32(2).unwrap();
            calculated_half_order
                .checked_div(&openssl_order, &two, &mut ctx)
                .unwrap();

            // Get our constant half order
            let our_half_order = BigNum::from_slice(&SECP256R1_HALF_ORDER).unwrap();

            // Compare the calculated half order with our constant
            assert_eq!(calculated_half_order, our_half_order);
        }

        #[test]
        fn test_secp256r1_order_relationships() {
            let group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1).unwrap();
            let mut ctx = BigNumContext::new().unwrap();
            let mut openssl_order = BigNum::new().unwrap();
            group.order(&mut openssl_order, &mut ctx).unwrap();

            let our_order = BigNum::from_slice(&SECP256R1_ORDER).unwrap();
            let our_order_minus_one = BigNum::from_slice(&SECP256R1_ORDER_MINUS_ONE).unwrap();
            let our_half_order = BigNum::from_slice(&SECP256R1_HALF_ORDER).unwrap();

            // Verify our order matches OpenSSL's order
            assert_eq!(our_order, openssl_order);

            // Verify order - 1
            let mut expected_order_minus_one = BigNum::new().unwrap();
            expected_order_minus_one
                .checked_sub(&openssl_order, &BigNum::from_u32(1).unwrap())
                .unwrap();
            assert_eq!(our_order_minus_one, expected_order_minus_one);

            // Verify half order
            let mut expected_half_order = BigNum::new().unwrap();
            expected_half_order
                .checked_div(&openssl_order, &BigNum::from_u32(2).unwrap(), &mut ctx)
                .unwrap();
            assert_eq!(our_half_order, expected_half_order);

            // Verify half order * 2 = order - 1
            let mut double_half_order = BigNum::new().unwrap();
            double_half_order
                .checked_mul(&our_half_order, &BigNum::from_u32(2).unwrap(), &mut ctx)
                .unwrap();
            assert_eq!(double_half_order, expected_order_minus_one);
        }
    }
}

#[cfg(any(target_arch = "wasm32", target_os = "solana"))]
mod target_arch {
    use {solana_feature_set::FeatureSet, solana_precompile_error::PrecompileError};

    pub fn verify(
        _data: &[u8],
        _instruction_datas: &[&[u8]],
        _feature_set: &FeatureSet,
    ) -> Result<(), PrecompileError> {
        Err(PrecompileError::InvalidSignature)
    }
}

pub use self::target_arch::*;