# Delta-Signature Predicates (Function-Level Binary Diffs)

## Module
BinaryIndex

## Status
IMPLEMENTED

## Description
Function-level delta signature predicates (v1 and v2) with signature generation, matching, and symbol change tracing. V2 adds symbol provenance and IR diffs, which is architecturally superior to the byte-level hunks proposed in the advisory.

## Implementation Details
- **Modules**: `src/BinaryIndex/__Libraries/StellaOps.BinaryIndex.DeltaSig/`
- **Key Classes**:
  - `DeltaSigPredicate` (`src/BinaryIndex/__Libraries/StellaOps.BinaryIndex.DeltaSig/Attestation/DeltaSigPredicate.cs`) - V1 predicate for attestation
  - `DeltaSigPredicateV2` (`src/BinaryIndex/__Libraries/StellaOps.BinaryIndex.DeltaSig/Attestation/DeltaSigPredicateV2.cs`) - V2 predicate with symbol provenance and IR diff support
  - `DeltaSigPredicateConverter` (`src/BinaryIndex/__Libraries/StellaOps.BinaryIndex.DeltaSig/Attestation/DeltaSigPredicateConverter.cs`) - converts between predicate versions
  - `DeltaSigAttestorIntegration` (`src/BinaryIndex/__Libraries/StellaOps.BinaryIndex.DeltaSig/Attestation/DeltaSigAttestorIntegration.cs`) - integrates delta-sig predicates with the Attestor module
  - `GroundTruthProvenanceResolver` (`src/BinaryIndex/__Libraries/StellaOps.BinaryIndex.DeltaSig/Provenance/GroundTruthProvenanceResolver.cs`) - enriches matches with symbol provenance data
  - `CfgExtractor` (`src/BinaryIndex/__Libraries/StellaOps.BinaryIndex.DeltaSig/CfgExtractor.cs`) - extracts control flow graphs for delta-sig generation
- **Models**: `Models.cs` in DeltaSig namespace - function match records, signature models
- **VEX Integration**: `DeltaSigVexBridge` (`src/BinaryIndex/__Libraries/StellaOps.BinaryIndex.DeltaSig/VexIntegration/`)

## E2E Test Plan
- [ ] Generate a V1 delta-sig predicate and verify it contains function-level diff data
- [ ] Generate a V2 delta-sig predicate and verify it includes symbol provenance and IR diff metadata
- [ ] Convert between V1 and V2 predicates via `DeltaSigPredicateConverter` and verify data fidelity
- [ ] Verify `DeltaSigAttestorIntegration` produces valid attestation predicates for the Attestor module
- [ ] Verify `GroundTruthProvenanceResolver` enriches function matches with provenance sources
- [ ] Verify V2 predicates flow into VEX observations via `DeltaSigVexBridge`