add support for Linux

Base58Swift/Base58.swift

@@ -1,8 +1,8 @@
 // Copyright Keefer Taylor, 2019.
 
-import BigInt
-import CommonCrypto
+@preconcurrency import BigInt
 import Foundation
+import Crypto
 
 /// A static utility class which provides Base58 encoding and decoding functionality.
 public enum Base58 {
@@ -96,12 +96,6 @@ public enum Base58 {
   /// - Parameter data: Input data to hash.
   /// - Returns: A sha256 hash of the input data.
   private static func sha256(_ data: [UInt8]) -> [UInt8] {
-    let res = NSMutableData(length: Int(CC_SHA256_DIGEST_LENGTH))!
-    CC_SHA256(
-      (Data(data) as NSData).bytes,
-      CC_LONG(data.count),
-      res.mutableBytes.assumingMemoryBound(to: UInt8.self)
-    )
-    return [UInt8](res as Data)
+    Array(SHA256.hash(data: Data(data)))
   }
 }

Package.swift

@@ -1,20 +1,28 @@
-// swift-tools-version:5.0
+// swift-tools-version:6.0
 import PackageDescription
 
 let package = Package(
     name: "Base58Swift",
+    platforms: [
+        .macOS(.v10_15),
+        .iOS(.v13),
+    ],
     products: [
         .library(
             name: "Base58Swift",
             targets: ["Base58Swift"])
     ],
     dependencies: [
-      .package(url: "https://github.com/attaswift/BigInt.git", from: "5.0.0")
+      .package(url: "https://github.com/attaswift/BigInt.git", from: "5.0.0"),
+      .package(url: "https://github.com/apple/swift-crypto.git", from: "3.0.0"),
     ],
     targets: [
         .target(
             name: "Base58Swift",
-            dependencies: ["BigInt"],
+            dependencies: [
+                "BigInt",
+                .product(name: "Crypto", package: "swift-crypto")
+            ],
             path: "Base58Swift"),
         .testTarget(
             name: "base58swiftTests",