PIIGuard

PIIGuard detects and optionally redacts personal identifiable information (PII) from inputs.

Overview

Property	Value
Latency	<10ms
Memory	50 KB
Async	No
ML Required	No

Supported PII Types

Category	Examples	Detection
Email	john@example.com	Regex
Phone	+1 555-123-4567	Regex
SSN	123-45-6789	Regex + validation
Credit Card	4111-1111-1111-1111	Regex + Luhn
IP Address	192.168.1.1	Regex + validation
API Keys	api_key=sk-xxx	Regex
DOB	01/15/1990	Regex
URL	https://example.com	Regex

Usage

Rust

use oxide_guard::{Guard, PIIGuard, RedactionStrategy, PIICategory};

let guard = PIIGuard::new("pii")
    .with_redaction(RedactionStrategy::Mask)
    .with_categories(&[PIICategory::Email, PIICategory::Phone, PIICategory::CreditCard]);

let result = guard.check("My email is john@example.com");
// result.sanitized = "My email is j***@example.com"

// Detect without redacting
let detections = guard.detect("Contact: john@example.com, 555-1234");
for detection in detections {
    println!("{}: {} at {}-{}",
        detection.category,
        detection.matched_text,
        detection.start,
        detection.end
    );
}

Python

from oxideshield import pii_guard

guard = pii_guard(redaction="mask")
result = guard.check("My email is john@example.com")
print(result.sanitized)  # My email is j***@example.com

# Detect PII
detections = guard.detect("Email: john@example.com")
for category, text, start, end in detections:
    print(f"{category}: {text}")

Redaction Strategies

Strategy	Example Input	Example Output
Mask	john@example.com	j***@example.com
Replace	john@example.com	[EMAIL]
Hash	john@example.com	[HASH:a1b2c3d4]
Remove	john@example.com	(empty)

Configuration

guards:
  pii:
    enabled: true
    redaction: mask
    block_on_detect: false  # Sanitize instead of block
    categories:
      - email
      - phone
      - ssn
      - credit_card
      - api_key

Credit Card Validation

PIIGuard uses the Luhn algorithm to validate credit card numbers, reducing false positives:

// Valid card (passes Luhn)
guard.check("Card: 4111-1111-1111-1111");  // Detected

// Invalid number (fails Luhn)
guard.check("Card: 1234-5678-9012-3456");  // Not detected