Use Google's CRC32C implementation

This is likely more efficient because it supports CPU accelerated instructions instead of a software implementation.

CryptoSwift usage has been removed since that was the only reason it was included.

Author: kthchew

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "CRC32C/crc32c"]
+	path = CRC32C/crc32c
+	url = git@github.com:kthchew/crc32c.git

CRC32C/GoogleCRC32C.h

@@ -0,0 +1,10 @@
+#import <Foundation/Foundation.h>
+
+//! Project version number for CRC32C.
+FOUNDATION_EXPORT double CRC32CVersionNumber;
+
+//! Project version string for CRC32C.
+FOUNDATION_EXPORT const unsigned char CRC32CVersionString[];
+
+// In this header, you should import all the public headers of your framework using statements like #import <CRC32C/PublicHeader.h>
+#import <GoogleCRC32C/crc32c.h>

CRC32C/crc32c

@@ -4,7 +4,6 @@
 import Algorithms
 import Foundation
 import os.log
-import CryptoSwift
 
 fileprivate let logger = Logger(subsystem: "com.kpchew.ExtendFS.ext4Extension", category: "FileExtentTree")
 
@@ -161,6 +160,6 @@ struct FileExtentTreeLevel {
     /// - Returns: The CRC32C checksum value.
     func calculateChecksum(seed: UInt32) throws -> UInt32 {
         let data = try self.toData().dropLast(MemoryLayout<UInt32>.size)
-        return ~data.byteArray.crc32c(seed: seed)
+        return ~data.crc32c(seed: seed)
     }
 }

ExtendFS Extension (ext4)/DiskStructures/FileExtentTreeLevel.swift

@@ -4,7 +4,6 @@
 import Foundation
 import FSKit
 import os.log
-import CryptoSwift
 
 struct IndexNode {
     static let logger = Logger(subsystem: "com.kpchew.ExtendFS.ext4Extension", category: "IndexNode")
@@ -92,7 +91,7 @@ struct IndexNode {
             var seedCsumData = Data()
             seedCsumData.appendLittleEndian(inodeNumber)
             seedCsumData.appendLittleEndian(generation)
-            self.metadataChecksumSeed = ~seedCsumData.byteArray.crc32c(seed: fsMetadataSeed)
+            self.metadataChecksumSeed = ~seedCsumData.crc32c(seed: fsMetadataSeed)
         } else {
             self.metadataChecksumSeed = nil
         }

ExtendFS Extension (ext4)/DiskStructures/IndexNode.swift

@@ -4,7 +4,6 @@
 import Foundation
 import FSKit
 import os.log
-import CryptoSwift
 
 fileprivate let logger = Logger(subsystem: "com.kpchew.ExtendFS.ext4Extension", category: "Superblock")
 
@@ -807,6 +806,6 @@ struct Superblock {
     func calculateChecksum() throws -> UInt32 {
         let data = try self.toData().dropLast(MemoryLayout<UInt32>.size)
 
-        return ~data.byteArray.crc32c()
+        return ~data.crc32c()
     }
 }

ExtendFS Extension (ext4)/DiskStructures/Superblock.swift

@@ -138,7 +138,7 @@ final class Ext4Volume: FSVolume, FSVolume.Operations, FSVolume.PathConfOperatio
             }
             var uuidData = Data()
             uuidData.append(uuid: uuid)
-            self.metadataChecksumSeed = ~uuidData.byteArray.crc32c()
+            self.metadataChecksumSeed = ~uuidData.crc32c()
         } else {
             self.metadataChecksumSeed = nil
         }

ExtendFS Extension (ext4)/Ext4Volume.swift

@@ -2,9 +2,9 @@
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
 <dict>
-	<key>com.apple.security.app-sandbox</key>
-	<true/>
 	<key>com.apple.developer.fskit.fsmodule</key>
 	<true/>
+	<key>com.apple.security.app-sandbox</key>
+	<true/>
 </dict>
 </plist>

ExtendFS Extension (ext4)/ExtendFSExtension.entitlements

@@ -2,6 +2,7 @@
 // See the LICENSE file in the root of the repository for full license details.
 
 import Foundation
+import GoogleCRC32C
 
 extension Data.Iterator {
     mutating func nextLittleEndian<T: FixedWidthInteger>() -> T? {
@@ -154,4 +155,15 @@ extension Data {
         let padding = [UInt8](repeating: 0, count: length - bytes.count)
         self.append(contentsOf: padding)
     }
+    
+    func crc32c(seed: UInt32? = nil) -> UInt32 {
+        self.withUnsafeBytes { buf in
+            guard let base = buf.baseAddress?.assumingMemoryBound(to: UInt8.self) else { return 0 }
+            if let seed {
+                return crc32c_extend(seed, base, buf.count)
+            } else {
+                return crc32c_value(base, buf.count)
+            }
+        }
+    }
 }