Rust · 22491 bytes Raw Blame History
1 //! Content integrity verification system for ZephyrFS
2 //!
3 //! Provides content-blind verification of data integrity using cryptographic proofs
4 //! and mathematical verification techniques without accessing plaintext content.
5
6 use anyhow::{Context, Result};
7 use ring::digest::{Context as DigestContext, SHA256, SHA512};
8 use serde::{Deserialize, Serialize};
9 use std::collections::HashMap;
10 use std::time::{SystemTime, UNIX_EPOCH};
11 use uuid::Uuid;
12
13 /// Integrity verification configuration
14 #[derive(Debug, Clone, Serialize, Deserialize)]
15 pub struct IntegrityConfig {
16 /// Enable cryptographic hash verification
17 pub hash_verification: bool,
18 /// Enable mathematical proof verification
19 pub proof_verification: bool,
20 /// Enable temporal integrity checking
21 pub temporal_verification: bool,
22 /// Maximum allowed age for integrity proofs (seconds)
23 pub max_proof_age: u64,
24 /// Required verification confidence level (0.0-1.0)
25 pub confidence_threshold: f64,
26 }
27
28 impl Default for IntegrityConfig {
29 fn default() -> Self {
30 Self {
31 hash_verification: true,
32 proof_verification: true,
33 temporal_verification: true,
34 max_proof_age: 3600, // 1 hour
35 confidence_threshold: 0.95,
36 }
37 }
38 }
39
40 /// Cryptographic integrity proof
41 #[derive(Debug, Clone, Serialize, Deserialize)]
42 pub struct IntegrityProof {
43 /// Unique proof identifier
44 pub proof_id: Uuid,
45 /// SHA-256 hash of encrypted content
46 pub content_hash_sha256: Vec<u8>,
47 /// SHA-512 hash of encrypted content
48 pub content_hash_sha512: Vec<u8>,
49 /// Merkle tree root for chunk verification
50 pub merkle_root: Vec<u8>,
51 /// Mathematical proof of completeness
52 pub completeness_proof: CompletenessProof,
53 /// Timestamp when proof was generated
54 pub timestamp: u64,
55 /// Content size in bytes
56 pub content_size: u64,
57 /// Additional metadata for verification
58 pub metadata: IntegrityMetadata,
59 }
60
61 /// Mathematical proof of content completeness
62 #[derive(Debug, Clone, Serialize, Deserialize)]
63 pub struct CompletenessProof {
64 /// Polynomial coefficients for content verification
65 pub polynomial_coefficients: Vec<u64>,
66 /// Reed-Solomon parity data
67 pub parity_data: Vec<u8>,
68 /// Checksum verification values
69 pub verification_checksums: Vec<u32>,
70 /// Content distribution fingerprint
71 pub distribution_fingerprint: Vec<u8>,
72 }
73
74 /// Additional integrity metadata
75 #[derive(Debug, Clone, Serialize, Deserialize)]
76 pub struct IntegrityMetadata {
77 /// Chunk count in the content
78 pub chunk_count: usize,
79 /// Content type classification
80 pub content_classification: String,
81 /// Compression ratio (if applicable)
82 pub compression_ratio: Option<f64>,
83 /// Entropy measure of the content
84 pub entropy_measure: f64,
85 }
86
87 /// Integrity verification result
88 #[derive(Debug, Clone)]
89 pub struct VerificationResult {
90 /// Whether verification passed
91 pub is_valid: bool,
92 /// Confidence score (0.0-1.0)
93 pub confidence: f64,
94 /// Individual check results
95 pub check_results: HashMap<String, bool>,
96 /// Detailed verification report
97 pub report: VerificationReport,
98 }
99
100 /// Detailed verification report
101 #[derive(Debug, Clone)]
102 pub struct VerificationReport {
103 /// Hash verification details
104 pub hash_verification: Option<HashVerificationResult>,
105 /// Proof verification details
106 pub proof_verification: Option<ProofVerificationResult>,
107 /// Temporal verification details
108 pub temporal_verification: Option<TemporalVerificationResult>,
109 /// Overall assessment
110 pub assessment: String,
111 }
112
113 /// Hash verification result details
114 #[derive(Debug, Clone)]
115 pub struct HashVerificationResult {
116 pub sha256_match: bool,
117 pub sha512_match: bool,
118 pub merkle_verification: bool,
119 pub hash_confidence: f64,
120 }
121
122 /// Proof verification result details
123 #[derive(Debug, Clone)]
124 pub struct ProofVerificationResult {
125 pub polynomial_verification: bool,
126 pub parity_verification: bool,
127 pub checksum_verification: bool,
128 pub distribution_verification: bool,
129 pub proof_confidence: f64,
130 }
131
132 /// Temporal verification result details
133 #[derive(Debug, Clone)]
134 pub struct TemporalVerificationResult {
135 pub proof_age_valid: bool,
136 pub timestamp_valid: bool,
137 pub temporal_confidence: f64,
138 }
139
140 /// Content integrity verification engine
141 pub struct IntegrityVerifier {
142 config: IntegrityConfig,
143 }
144
145 impl IntegrityVerifier {
146 /// Create new integrity verifier with configuration
147 pub fn new(config: IntegrityConfig) -> Self {
148 Self { config }
149 }
150
151 /// Create integrity verifier with default configuration
152 pub fn default() -> Self {
153 Self {
154 config: IntegrityConfig::default(),
155 }
156 }
157
158 /// Generate integrity proof for encrypted content
159 pub fn generate_proof(&self, encrypted_content: &[u8]) -> Result<IntegrityProof> {
160 let proof_id = Uuid::new_v4();
161 let timestamp = SystemTime::now()
162 .duration_since(UNIX_EPOCH)
163 .context("Failed to get timestamp")?
164 .as_secs();
165
166 // Generate cryptographic hashes
167 let sha256_hash = self.compute_sha256(encrypted_content)?;
168 let sha512_hash = self.compute_sha512(encrypted_content)?;
169 let merkle_root = self.compute_merkle_root(encrypted_content)?;
170
171 // Generate mathematical completeness proof
172 let completeness_proof = self.generate_completeness_proof(encrypted_content)?;
173
174 // Generate metadata
175 let metadata = self.generate_metadata(encrypted_content)?;
176
177 Ok(IntegrityProof {
178 proof_id,
179 content_hash_sha256: sha256_hash,
180 content_hash_sha512: sha512_hash,
181 merkle_root,
182 completeness_proof,
183 timestamp,
184 content_size: encrypted_content.len() as u64,
185 metadata,
186 })
187 }
188
189 /// Verify content integrity against proof
190 pub fn verify_integrity(
191 &self,
192 encrypted_content: &[u8],
193 proof: &IntegrityProof,
194 ) -> Result<VerificationResult> {
195 let mut check_results = HashMap::new();
196 let mut confidence_scores = Vec::new();
197
198 // Initialize report components
199 let mut hash_verification = None;
200 let mut proof_verification = None;
201 let mut temporal_verification = None;
202
203 // Perform hash verification
204 if self.config.hash_verification {
205 let hash_result = self.verify_hashes(encrypted_content, proof)?;
206 let hash_passed = hash_result.sha256_match && hash_result.sha512_match && hash_result.merkle_verification;
207
208 check_results.insert("hash_verification".to_string(), hash_passed);
209 confidence_scores.push(hash_result.hash_confidence);
210 hash_verification = Some(hash_result);
211 }
212
213 // Perform proof verification
214 if self.config.proof_verification {
215 let proof_result = self.verify_mathematical_proof(encrypted_content, &proof.completeness_proof)?;
216 let proof_passed = proof_result.polynomial_verification
217 && proof_result.parity_verification
218 && proof_result.checksum_verification
219 && proof_result.distribution_verification;
220
221 check_results.insert("proof_verification".to_string(), proof_passed);
222 confidence_scores.push(proof_result.proof_confidence);
223 proof_verification = Some(proof_result);
224 }
225
226 // Perform temporal verification
227 if self.config.temporal_verification {
228 let temporal_result = self.verify_temporal_integrity(proof)?;
229 let temporal_passed = temporal_result.proof_age_valid && temporal_result.timestamp_valid;
230
231 check_results.insert("temporal_verification".to_string(), temporal_passed);
232 confidence_scores.push(temporal_result.temporal_confidence);
233 temporal_verification = Some(temporal_result);
234 }
235
236 // Calculate overall confidence and validity
237 let overall_confidence = if confidence_scores.is_empty() {
238 0.0
239 } else {
240 confidence_scores.iter().sum::<f64>() / confidence_scores.len() as f64
241 };
242
243 let is_valid = check_results.values().all(|&v| v)
244 && overall_confidence >= self.config.confidence_threshold;
245
246 let assessment = self.generate_assessment(&check_results, overall_confidence);
247
248 let report = VerificationReport {
249 hash_verification,
250 proof_verification,
251 temporal_verification,
252 assessment,
253 };
254
255 Ok(VerificationResult {
256 is_valid,
257 confidence: overall_confidence,
258 check_results,
259 report,
260 })
261 }
262
263 /// Compute SHA-256 hash of content
264 fn compute_sha256(&self, content: &[u8]) -> Result<Vec<u8>> {
265 let mut context = DigestContext::new(&SHA256);
266 context.update(content);
267 Ok(context.finish().as_ref().to_vec())
268 }
269
270 /// Compute SHA-512 hash of content
271 fn compute_sha512(&self, content: &[u8]) -> Result<Vec<u8>> {
272 let mut context = DigestContext::new(&SHA512);
273 context.update(content);
274 Ok(context.finish().as_ref().to_vec())
275 }
276
277 /// Compute Merkle tree root for chunk verification
278 fn compute_merkle_root(&self, content: &[u8]) -> Result<Vec<u8>> {
279 const CHUNK_SIZE: usize = 4096;
280 let mut leaf_hashes = Vec::new();
281
282 // Generate leaf hashes for each chunk
283 for chunk in content.chunks(CHUNK_SIZE) {
284 let mut context = DigestContext::new(&SHA256);
285 context.update(chunk);
286 leaf_hashes.push(context.finish().as_ref().to_vec());
287 }
288
289 // Build Merkle tree bottom-up
290 let mut level = leaf_hashes;
291 while level.len() > 1 {
292 let mut next_level = Vec::new();
293
294 for pair in level.chunks(2) {
295 let mut context = DigestContext::new(&SHA256);
296 context.update(&pair[0]);
297 if pair.len() > 1 {
298 context.update(&pair[1]);
299 } else {
300 // Odd number of hashes, duplicate the last one
301 context.update(&pair[0]);
302 }
303 next_level.push(context.finish().as_ref().to_vec());
304 }
305
306 level = next_level;
307 }
308
309 level.into_iter().next().unwrap_or_else(|| {
310 let mut context = DigestContext::new(&SHA256);
311 context.update(b"empty");
312 context.finish().as_ref().to_vec()
313 }).into()
314 }
315
316 /// Generate mathematical completeness proof
317 fn generate_completeness_proof(&self, content: &[u8]) -> Result<CompletenessProof> {
318 // Generate polynomial coefficients based on content distribution
319 let polynomial_coefficients = self.compute_polynomial_coefficients(content);
320
321 // Generate Reed-Solomon parity data for error detection
322 let parity_data = self.generate_reed_solomon_parity(content)?;
323
324 // Generate verification checksums
325 let verification_checksums = self.compute_verification_checksums(content);
326
327 // Generate content distribution fingerprint
328 let distribution_fingerprint = self.compute_distribution_fingerprint(content)?;
329
330 Ok(CompletenessProof {
331 polynomial_coefficients,
332 parity_data,
333 verification_checksums,
334 distribution_fingerprint,
335 })
336 }
337
338 /// Compute polynomial coefficients for content verification
339 fn compute_polynomial_coefficients(&self, content: &[u8]) -> Vec<u64> {
340 const POLY_DEGREE: usize = 8;
341 let mut coefficients = vec![0u64; POLY_DEGREE];
342
343 for (i, &byte) in content.iter().enumerate() {
344 let coeff_idx = i % POLY_DEGREE;
345 coefficients[coeff_idx] = coefficients[coeff_idx]
346 .wrapping_add(byte as u64)
347 .wrapping_mul(i as u64 + 1);
348 }
349
350 coefficients
351 }
352
353 /// Generate Reed-Solomon parity data
354 fn generate_reed_solomon_parity(&self, content: &[u8]) -> Result<Vec<u8>> {
355 // Simplified Reed-Solomon implementation for demonstration
356 // In production, use a proper Reed-Solomon library
357 const PARITY_SIZE: usize = 16;
358 let mut parity = vec![0u8; PARITY_SIZE];
359
360 for (i, &byte) in content.iter().enumerate() {
361 let parity_idx = i % PARITY_SIZE;
362 parity[parity_idx] ^= byte;
363 }
364
365 Ok(parity)
366 }
367
368 /// Compute verification checksums
369 fn compute_verification_checksums(&self, content: &[u8]) -> Vec<u32> {
370 let mut checksums = Vec::new();
371 const CHECKSUM_COUNT: usize = 4;
372
373 for i in 0..CHECKSUM_COUNT {
374 let mut checksum = 0u32;
375 let start = (content.len() * i) / CHECKSUM_COUNT;
376 let end = (content.len() * (i + 1)) / CHECKSUM_COUNT;
377
378 for &byte in &content[start..end] {
379 checksum = checksum.wrapping_add(byte as u32);
380 checksum = checksum.wrapping_mul(31);
381 }
382
383 checksums.push(checksum);
384 }
385
386 checksums
387 }
388
389 /// Compute content distribution fingerprint
390 fn compute_distribution_fingerprint(&self, content: &[u8]) -> Result<Vec<u8>> {
391 let mut frequency = [0u32; 256];
392
393 // Count byte frequency
394 for &byte in content {
395 frequency[byte as usize] += 1;
396 }
397
398 // Create fingerprint from frequency distribution
399 let mut context = DigestContext::new(&SHA256);
400 for count in frequency {
401 context.update(&count.to_le_bytes());
402 }
403
404 Ok(context.finish().as_ref().to_vec())
405 }
406
407 /// Generate integrity metadata
408 fn generate_metadata(&self, content: &[u8]) -> Result<IntegrityMetadata> {
409 const CHUNK_SIZE: usize = 4096;
410 let chunk_count = (content.len() + CHUNK_SIZE - 1) / CHUNK_SIZE;
411
412 // Calculate entropy
413 let entropy_measure = self.calculate_entropy(content);
414
415 Ok(IntegrityMetadata {
416 chunk_count,
417 content_classification: "encrypted_data".to_string(),
418 compression_ratio: None, // Could be calculated if compression is used
419 entropy_measure,
420 })
421 }
422
423 /// Calculate content entropy
424 fn calculate_entropy(&self, content: &[u8]) -> f64 {
425 let mut frequency = [0u32; 256];
426
427 // Count byte frequency
428 for &byte in content {
429 frequency[byte as usize] += 1;
430 }
431
432 // Calculate Shannon entropy
433 let total = content.len() as f64;
434 let mut entropy = 0.0;
435
436 for count in frequency {
437 if count > 0 {
438 let probability = count as f64 / total;
439 entropy -= probability * probability.log2();
440 }
441 }
442
443 entropy
444 }
445
446 /// Verify cryptographic hashes
447 fn verify_hashes(&self, content: &[u8], proof: &IntegrityProof) -> Result<HashVerificationResult> {
448 let sha256_hash = self.compute_sha256(content)?;
449 let sha512_hash = self.compute_sha512(content)?;
450 let merkle_root = self.compute_merkle_root(content)?;
451
452 let sha256_match = sha256_hash == proof.content_hash_sha256;
453 let sha512_match = sha512_hash == proof.content_hash_sha512;
454 let merkle_verification = merkle_root == proof.merkle_root;
455
456 let hash_confidence = match (sha256_match, sha512_match, merkle_verification) {
457 (true, true, true) => 1.0,
458 (true, true, false) | (true, false, true) | (false, true, true) => 0.7,
459 (true, false, false) | (false, true, false) | (false, false, true) => 0.3,
460 (false, false, false) => 0.0,
461 };
462
463 Ok(HashVerificationResult {
464 sha256_match,
465 sha512_match,
466 merkle_verification,
467 hash_confidence,
468 })
469 }
470
471 /// Verify mathematical proof
472 fn verify_mathematical_proof(
473 &self,
474 content: &[u8],
475 proof: &CompletenessProof,
476 ) -> Result<ProofVerificationResult> {
477 // Verify polynomial coefficients
478 let computed_coefficients = self.compute_polynomial_coefficients(content);
479 let polynomial_verification = computed_coefficients == proof.polynomial_coefficients;
480
481 // Verify Reed-Solomon parity
482 let computed_parity = self.generate_reed_solomon_parity(content)?;
483 let parity_verification = computed_parity == proof.parity_data;
484
485 // Verify checksums
486 let computed_checksums = self.compute_verification_checksums(content);
487 let checksum_verification = computed_checksums == proof.verification_checksums;
488
489 // Verify distribution fingerprint
490 let computed_fingerprint = self.compute_distribution_fingerprint(content)?;
491 let distribution_verification = computed_fingerprint == proof.distribution_fingerprint;
492
493 let verified_count = [
494 polynomial_verification,
495 parity_verification,
496 checksum_verification,
497 distribution_verification,
498 ]
499 .iter()
500 .filter(|&&v| v)
501 .count();
502
503 let proof_confidence = verified_count as f64 / 4.0;
504
505 Ok(ProofVerificationResult {
506 polynomial_verification,
507 parity_verification,
508 checksum_verification,
509 distribution_verification,
510 proof_confidence,
511 })
512 }
513
514 /// Verify temporal integrity
515 fn verify_temporal_integrity(&self, proof: &IntegrityProof) -> Result<TemporalVerificationResult> {
516 let current_time = SystemTime::now()
517 .duration_since(UNIX_EPOCH)
518 .context("Failed to get current timestamp")?
519 .as_secs();
520
521 let proof_age = current_time.saturating_sub(proof.timestamp);
522 let proof_age_valid = proof_age <= self.config.max_proof_age;
523
524 // Basic timestamp validation (not too far in the future)
525 let timestamp_valid = proof.timestamp <= current_time + 300; // Allow 5 minutes clock skew
526
527 let temporal_confidence = match (proof_age_valid, timestamp_valid) {
528 (true, true) => 1.0,
529 (true, false) | (false, true) => 0.5,
530 (false, false) => 0.0,
531 };
532
533 Ok(TemporalVerificationResult {
534 proof_age_valid,
535 timestamp_valid,
536 temporal_confidence,
537 })
538 }
539
540 /// Generate assessment report
541 fn generate_assessment(&self, check_results: &HashMap<String, bool>, confidence: f64) -> String {
542 let passed_checks = check_results.values().filter(|&&v| v).count();
543 let total_checks = check_results.len();
544
545 if passed_checks == total_checks && confidence >= self.config.confidence_threshold {
546 format!(
547 "VERIFIED: All integrity checks passed ({}/{}) with {:.1}% confidence",
548 passed_checks, total_checks, confidence * 100.0
549 )
550 } else if passed_checks >= total_checks / 2 {
551 format!(
552 "PARTIAL: {}/{} checks passed with {:.1}% confidence - review recommended",
553 passed_checks, total_checks, confidence * 100.0
554 )
555 } else {
556 format!(
557 "FAILED: Only {}/{} checks passed with {:.1}% confidence - integrity compromised",
558 passed_checks, total_checks, confidence * 100.0
559 )
560 }
561 }
562 }
563
564 #[cfg(test)]
565 mod tests {
566 use super::*;
567
568 #[test]
569 fn test_integrity_proof_generation() -> Result<()> {
570 let verifier = IntegrityVerifier::default();
571 let test_content = b"Test content for integrity verification";
572
573 let proof = verifier.generate_proof(test_content)?;
574
575 assert_eq!(proof.content_size, test_content.len() as u64);
576 assert!(!proof.content_hash_sha256.is_empty());
577 assert!(!proof.content_hash_sha512.is_empty());
578 assert!(!proof.merkle_root.is_empty());
579
580 Ok(())
581 }
582
583 #[test]
584 fn test_integrity_verification_success() -> Result<()> {
585 let verifier = IntegrityVerifier::default();
586 let test_content = b"Test content for successful verification";
587
588 let proof = verifier.generate_proof(test_content)?;
589 let result = verifier.verify_integrity(test_content, &proof)?;
590
591 assert!(result.is_valid);
592 assert!(result.confidence >= 0.95);
593
594 Ok(())
595 }
596
597 #[test]
598 fn test_integrity_verification_failure() -> Result<()> {
599 let verifier = IntegrityVerifier::default();
600 let original_content = b"Original test content";
601 let tampered_content = b"Tampered test content";
602
603 let proof = verifier.generate_proof(original_content)?;
604 let result = verifier.verify_integrity(tampered_content, &proof)?;
605
606 assert!(!result.is_valid);
607 assert!(result.confidence < 0.95);
608
609 Ok(())
610 }
611
612 #[test]
613 fn test_entropy_calculation() {
614 let verifier = IntegrityVerifier::default();
615
616 // Test high entropy content (random-like)
617 let high_entropy_content: Vec<u8> = (0..256).collect();
618 let high_entropy = verifier.calculate_entropy(&high_entropy_content);
619
620 // Test low entropy content (repetitive)
621 let low_entropy_content = vec![0u8; 256];
622 let low_entropy = verifier.calculate_entropy(&low_entropy_content);
623
624 assert!(high_entropy > low_entropy);
625 assert!(high_entropy > 7.0); // Should be close to 8.0 for uniform distribution
626 assert!(low_entropy < 1.0); // Should be 0.0 for uniform content
627 }
628
629 #[test]
630 fn test_merkle_tree_verification() -> Result<()> {
631 let verifier = IntegrityVerifier::default();
632 let test_content = b"Test content for Merkle tree verification with multiple chunks";
633
634 let merkle_root1 = verifier.compute_merkle_root(test_content)?;
635 let merkle_root2 = verifier.compute_merkle_root(test_content)?;
636
637 // Same content should produce same Merkle root
638 assert_eq!(merkle_root1, merkle_root2);
639
640 // Different content should produce different Merkle root
641 let different_content = b"Different test content for Merkle tree verification";
642 let different_root = verifier.compute_merkle_root(different_content)?;
643 assert_ne!(merkle_root1, different_root);
644
645 Ok(())
646 }
647 }