---
title: "Cryptographic Security Enhancements"
description: "Comprehensive overview of cryptographic security enhancements in the Sonr blockchain"
icon: "lock"
sidebar:
  label: "Cryptography Usage"
---

:::info
This document details the comprehensive cryptographic security enhancements
implemented in the Sonr blockchain to address critical vulnerabilities and
strengthen the overall security posture.
:::

:::note
This page is a historical summary of the hardening work tracked in the
changelog. The primitives themselves — `mpc`, `keys`, `ucan`, `vrf`, `argon2`,
`password`, and `wasm` — live in
[`github.com/sonr-io/crypto`](https://github.com/sonr-io/crypto) and are
documented on that repository's own docs site. Chain-side usage is covered in
the [module reference](/reference/modules/did).
:::

## WASM Plugin Security

### SHA256 Hash Verification

:::warning
All WASM plugins are now verified using SHA256 hashes before execution to
prevent tampering and ensure integrity.
:::

**Implementation**: `crypto/wasm/verifier.go`

```go
// Usage example
verifier := wasm.NewHashVerifier()
hash := verifier.ComputeHash(wasmBytes)
verifier.AddTrustedHash("motr.wasm", hash)

// Verify before execution
err := verifier.VerifyHash("motr.wasm", wasmBytes)
if err != nil {
// Plugin verification failed - do not execute
}
```

**Features**:

- Automatic hash computation on plugin load
- Hash chain verification for secure updates
- Trusted hash whitelist management
- Maximum size enforcement (10MB default)

### Ed25519 Code Signing

:::warning
WASM plugins must be signed with Ed25519 signatures to ensure authenticity and
prevent unauthorized modifications.
:::

**Implementation**: `crypto/wasm/signer.go`

```go
// Sign a plugin
signer := wasm.NewSigner(privateKey, publicKey)
signature, err := signer.SignModule(wasmBytes, "motr.wasm", "v1.0.0")

// Verify signature
manifest := &wasm.SignatureManifest{
ModuleHash: hash,
Signatures: []wasm.SignatureEntry{\*signature},
TrustedKeys: trustedKeys,
}
err = signer.VerifyWithManifest(wasmBytes, manifest)
```

### Further sections

The remaining hardening areas — password policy, deterministic ECDSA,
signature canonicalization, and key derivation — are implemented in
[`github.com/sonr-io/crypto`](https://github.com/sonr-io/crypto); see that
repository's docs for parameter-level detail.

## Security Considerations

:::warning
### Best Practices 1. **Always validate passwords** before use 2. **Never
store passwords in plaintext** or logs 3. **Use deterministic ECDSA** for all
signatures 4. **Canonicalize all signatures** before storage 5. **Verify WASM
plugins** before execution
:::

## Support

:::info
For questions or issues related to cryptographic security: 1. Check the test
suites for usage examples 2. Review the security test scenarios 3. Open an
issue on GitHub with the `security` label 4. Contact the security team for
sensitive issues
:::

## Changelog

### Version 0.10.34

- Added WASM hash verification (`crypto/wasm/verifier.go`)
- Added Ed25519 code signing (`crypto/wasm/signer.go`)
- Replaced hardcoded passwords with secure validation (`crypto/password/validator.go`)
- Implemented Argon2id key derivation (`crypto/argon2/kdf.go`)
- Added RFC 6979 deterministic ECDSA (`crypto/ecdsa/deterministic.go`)
- Implemented signature canonicalization (`crypto/ecdsa/canonical.go`)
- Added comprehensive security test suite (`crypto/security_test.go`)

---

_Last Updated: 2024_
_Security Contact: security@sonr.io_