package com.capacitor.audioengine; import android.text.TextUtils; import java.io.File; import java.net.URL; import java.util.regex.Pattern; /** * Utility class for validating inputs to prevent security issues and ensure data integrity */ public class ValidationUtils { private static final String TAG = "ValidationUtils"; // Regex patterns for validation private static final Pattern VALID_FILENAME_PATTERN = Pattern.compile("^[a-zA-Z0-9._-]+$"); private static final Pattern PATH_TRAVERSAL_PATTERN = Pattern.compile(".*(\\.\\.|~|\\\\|//).*"); // File size limits (in bytes) private static final long MAX_AUDIO_FILE_SIZE = 500 * 1024 * 1024; // 500MB private static final long MIN_AUDIO_FILE_SIZE = 100; // 100 bytes // Audio parameter limits private static final int MIN_SAMPLE_RATE = 8000; private static final int MAX_SAMPLE_RATE = 192000; private static final int MIN_BITRATE = 32000; private static final int MAX_BITRATE = 512000; private static final int MIN_CHANNELS = 1; private static final int MAX_CHANNELS = 8; private static final double MIN_DURATION = 0.1; // 100ms private static final double MAX_DURATION = 24 * 3600; // 24 hours /** * Validate URI is not null or empty */ public static void validateUri(String uri) throws IllegalArgumentException { if (TextUtils.isEmpty(uri)) { throw new IllegalArgumentException(AudioEngineError.INVALID_URI.getMessage()); } if (uri.trim().isEmpty()) { throw new IllegalArgumentException(AudioEngineError.INVALID_URI.getMessage()); } } /** * Validate and sanitize file path to prevent path traversal attacks */ public static void validateFilePath(String path) throws SecurityException { if (TextUtils.isEmpty(path)) { throw new SecurityException(AudioEngineError.INVALID_FILE_PATH.getMessage()); } // Check for path traversal attempts if (PATH_TRAVERSAL_PATTERN.matcher(path).matches()) { throw new SecurityException(AudioEngineError.INVALID_FILE_PATH.getDetailedMessage("Path traversal attempt detected")); } // Additional security checks String normalizedPath = path.toLowerCase(); if (normalizedPath.contains("../") || normalizedPath.contains("..\\") || normalizedPath.contains("~/") || normalizedPath.startsWith("/system") || normalizedPath.startsWith("/proc") || normalizedPath.startsWith("/dev")) { throw new SecurityException(AudioEngineError.INVALID_FILE_PATH.getDetailedMessage("Access to restricted path")); } } /** * Validate time range for audio operations */ public static void validateTimeRange(double startTime, double endTime) throws IllegalArgumentException { if (startTime < 0) { throw new IllegalArgumentException(AudioEngineError.INVALID_TIME_RANGE.getDetailedMessage("Start time cannot be negative")); } if (endTime < 0) { throw new IllegalArgumentException(AudioEngineError.INVALID_TIME_RANGE.getDetailedMessage("End time cannot be negative")); } if (endTime <= startTime) { throw new IllegalArgumentException(AudioEngineError.INVALID_TIME_RANGE.getDetailedMessage("End time must be greater than start time")); } double duration = endTime - startTime; if (duration < MIN_DURATION) { throw new IllegalArgumentException(AudioEngineError.INVALID_TIME_RANGE.getDetailedMessage("Duration too short (minimum " + MIN_DURATION + " seconds)")); } if (duration > MAX_DURATION) { throw new IllegalArgumentException(AudioEngineError.INVALID_TIME_RANGE.getDetailedMessage("Duration too long (maximum " + MAX_DURATION + " seconds)")); } } /** * Validate audio recording parameters */ public static void validateAudioParameters(int sampleRate, int channels, int bitrate) throws IllegalArgumentException { if (sampleRate < MIN_SAMPLE_RATE || sampleRate > MAX_SAMPLE_RATE) { throw new IllegalArgumentException(AudioEngineError.INVALID_AUDIO_PARAMETERS.getDetailedMessage( "Sample rate must be between " + MIN_SAMPLE_RATE + " and " + MAX_SAMPLE_RATE + " Hz")); } if (channels < MIN_CHANNELS || channels > MAX_CHANNELS) { throw new IllegalArgumentException(AudioEngineError.INVALID_AUDIO_PARAMETERS.getDetailedMessage( "Channels must be between " + MIN_CHANNELS + " and " + MAX_CHANNELS)); } if (bitrate < MIN_BITRATE || bitrate > MAX_BITRATE) { throw new IllegalArgumentException(AudioEngineError.INVALID_AUDIO_PARAMETERS.getDetailedMessage( "Bitrate must be between " + MIN_BITRATE + " and " + MAX_BITRATE + " bps")); } } /** * Validate file exists and is readable */ public static void validateFileExists(String filePath) throws IllegalArgumentException { validateFilePath(filePath); File file = new File(filePath); if (!file.exists()) { throw new IllegalArgumentException(AudioEngineError.FILE_NOT_FOUND.getDetailedMessage("File does not exist: " + filePath)); } if (!file.canRead()) { throw new IllegalArgumentException(AudioEngineError.FILE_NOT_FOUND.getDetailedMessage("Cannot read file: " + filePath)); } long fileSize = file.length(); if (fileSize < MIN_AUDIO_FILE_SIZE) { throw new IllegalArgumentException(AudioEngineError.INVALID_PARAMETERS.getDetailedMessage("File too small: " + fileSize + " bytes")); } if (fileSize > MAX_AUDIO_FILE_SIZE) { throw new IllegalArgumentException(AudioEngineError.INVALID_PARAMETERS.getDetailedMessage("File too large: " + fileSize + " bytes")); } } /** * Validate remote URL */ public static void validateRemoteUrl(String url) throws IllegalArgumentException { validateUri(url); try { URL urlObj = new URL(url); String protocol = urlObj.getProtocol().toLowerCase(); if (!protocol.equals("http") && !protocol.equals("https")) { throw new IllegalArgumentException(AudioEngineError.INVALID_URI.getDetailedMessage("Only HTTP/HTTPS URLs are supported")); } String host = urlObj.getHost(); if (TextUtils.isEmpty(host)) { throw new IllegalArgumentException(AudioEngineError.INVALID_URI.getDetailedMessage("Invalid host in URL")); } // Prevent access to localhost/private IPs (basic check) if (host.equals("localhost") || host.equals("127.0.0.1") || host.startsWith("192.168.") || host.startsWith("10.") || host.startsWith("172.")) { throw new IllegalArgumentException(AudioEngineError.INVALID_URI.getDetailedMessage("Access to private/local URLs not allowed")); } } catch (Exception e) { throw new IllegalArgumentException(AudioEngineError.INVALID_URI.getDetailedMessage("Malformed URL: " + e.getMessage())); } } /** * Validate filename for security */ public static void validateFilename(String filename) throws SecurityException { if (TextUtils.isEmpty(filename)) { throw new SecurityException(AudioEngineError.INVALID_PARAMETERS.getDetailedMessage("Filename cannot be empty")); } if (!VALID_FILENAME_PATTERN.matcher(filename).matches()) { throw new SecurityException(AudioEngineError.INVALID_PARAMETERS.getDetailedMessage("Filename contains invalid characters")); } if (filename.length() > 255) { throw new SecurityException(AudioEngineError.INVALID_PARAMETERS.getDetailedMessage("Filename too long")); } } /** * Check if URL is a remote URL (HTTP/HTTPS) */ public static boolean isRemoteUrl(String uri) { return uri != null && (uri.startsWith("http://") || uri.startsWith("https://")); } /** * Sanitize filename by removing invalid characters */ public static String sanitizeFilename(String filename) { if (TextUtils.isEmpty(filename)) { return "audio_file"; } // Replace invalid characters with underscores String sanitized = filename.replaceAll("[^a-zA-Z0-9._-]", "_"); // Ensure it's not too long if (sanitized.length() > 255) { sanitized = sanitized.substring(0, 255); } // Ensure it's not empty after sanitization if (sanitized.isEmpty()) { sanitized = "audio_file"; } return sanitized; } }