Use calculated sBox

CryptoSwift.xcodeproj/xcshareddata/xcschemes/CryptoSwift.xcscheme

@@ -37,7 +37,7 @@
       </BuildActionEntries>
    </BuildAction>
    <TestAction
-      buildConfiguration = "Release"
+      buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
       shouldUseLaunchSchemeArgsEnv = "YES"

CryptoSwift/AES.swift

@@ -45,46 +45,12 @@ final public class AES {
     }
     private let key:[UInt8]
     private let iv:[UInt8]?
-    public lazy var expandedKey:[[UInt32]] = { self.expandKey(self.key, variant: self.variant) }()
-    public lazy var expandedKeyInv:[[UInt32]] = { self.expandKeyInv(self.key, variant: self.variant) }()
+    public lazy var expandedKey:[[UInt32]] = self.expandKey(self.key, variant: self.variant)
+    public lazy var expandedKeyInv:[[UInt32]] = self.expandKeyInv(self.key, variant: self.variant)
     
-//    private lazy var sBoxes:(sBox:[UInt8], invSBox:[UInt8]) = self.calculateSBox()
-//    private lazy var sBox:[UInt8] = self.sBoxes.sBox
-//    private lazy var invSBox:[UInt8] = self.sBoxes.invSBox
-    
-    private let sBox:[UInt32] = [0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
-        0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
-        0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
-        0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
-        0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
-        0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
-        0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
-        0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
-        0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
-        0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
-        0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
-        0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
-        0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
-        0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
-        0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
-        0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16]
-    
-    private let sBoxInv:[UInt32] = [0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb,
-        0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb,
-        0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e,
-        0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25,
-        0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92,
-        0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84,
-        0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06,
-        0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b,
-        0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73,
-        0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e,
-        0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b,
-        0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4,
-        0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f,
-        0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef,
-        0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61,
-        0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d]
+    private lazy var sBoxes:(sBox:[UInt32], invSBox:[UInt32]) = self.calculateSBox()
+    private lazy var sBox:[UInt32] = self.sBoxes.sBox
+    private lazy var sBoxInv:[UInt32] = self.sBoxes.invSBox
     
     // Parameters for Linear Congruence Generators
     private let Rcon:[UInt8] = [
@@ -1100,58 +1066,13 @@ final public class AES {
         }
         return convertExpandedKey(w)
     }
-    
-    private func expandKey(key:[UInt8], variant:AESVariant) -> [UInt8] {
-        
-        /*
-        * Function used in the Key Expansion routine that takes a four-byte
-        * input word and applies an S-box to each of the four bytes to
-        * produce an output word.
-        */
-        func subWord(word:[UInt8]) -> [UInt8] {
-            var result = word
-            for i in 0..<4 {
-                result[i] = UInt8(sBox[Int(word[i])])
-            }
-            return result
-        }
-        
-        var w = [UInt8](count: variant.Nb * (variant.Nr + 1) * 4, repeatedValue: 0)
-        for i in 0..<variant.Nk {
-            for wordIdx in 0..<4 {
-                w[(4*i)+wordIdx] = key[(4*i)+wordIdx]
-            }
-        }
-        
-        var tmp:[UInt8]
-        for (var i = variant.Nk; i < variant.Nb * (variant.Nr + 1); i++) {
-            tmp = [UInt8](count: 4, repeatedValue: 0)
-            
-            for wordIdx in 0..<4 {
-                tmp[wordIdx] = w[4*(i-1)+wordIdx]
-            }
-            if ((i % variant.Nk) == 0) {
-                let rotWord = rotateLeft(UInt32.withBytes(tmp), 8).bytes(sizeof(UInt32)) // RotWord
-                tmp = subWord(rotWord)
-                tmp[0] = tmp.first! ^ Rcon[i/variant.Nk]
-            } else if (variant.Nk > 6 && (i % variant.Nk) == 4) {
-                tmp = subWord(tmp)
-            }
-            
-            // xor array of bytes
-            for wordIdx in 0..<4 {
-                w[4*i+wordIdx] = w[4*(i-variant.Nk)+wordIdx]^tmp[wordIdx];
-            }
-        }
-        return w;
-    }
 }
 
 extension AES {
     // MARK: S-Box
     
-    private func calculateSBox() -> (sBox:[UInt8], invSBox:[UInt8]) {
-        var sbox = [UInt8](count: 256, repeatedValue: 0)
+    private func calculateSBox() -> (sBox:[UInt32], invSBox:[UInt32]) {
+        var sbox = [UInt32](count: 256, repeatedValue: 0)
         var invsbox = sbox
         sbox[0] = 0x63
         
@@ -1166,8 +1087,8 @@ extension AES {
             
             let s = 0x63 ^ q ^ rotateLeft(q, 1) ^ rotateLeft(q, 2) ^ rotateLeft(q, 3) ^ rotateLeft(q, 4)
             
-            sbox[Int(p)] = s
-            invsbox[Int(s)] = p
+            sbox[Int(p)] = UInt32(s)
+            invsbox[Int(s)] = UInt32(p)
         } while (p != 1)
         
         return (sBox: sbox, invSBox: invsbox)

CryptoSwiftTests/AESTests.swift

@@ -122,8 +122,9 @@ final class AESTests: XCTestCase {
         let key:[UInt8] = [0x2b,0x7e,0x15,0x16,0x28,0xae,0xd2,0xa6,0xab,0xf7,0x15,0x88,0x09,0xcf,0x4f,0x3c];
         let iv:[UInt8] = [0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0A,0x0B,0x0C,0x0D,0x0E,0x0F]
         let message = [UInt8](count: 1024 * 1024, repeatedValue: 7)
+        let aes = AES(key: key, iv: iv, blockMode: .CBC)
         measureMetrics([XCTPerformanceMetric_WallClockTime], automaticallyStartMeasuring: true, forBlock: { () -> Void in
-            try! AES(key: key, iv: iv, blockMode: .CBC)?.encrypt(message, padding: PKCS7())
+            try! aes?.encrypt(message, padding: PKCS7())
         })
     }
 
@@ -131,8 +132,9 @@ final class AESTests: XCTestCase {
         let key:[UInt8] = [0x2b,0x7e,0x15,0x16,0x28,0xae,0xd2,0xa6,0xab,0xf7,0x15,0x88,0x09,0xcf,0x4f,0x3c];
         let iv:[UInt8] = [0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0A,0x0B,0x0C,0x0D,0x0E,0x0F]
         let message = [UInt8](count: 1024 * 1024, repeatedValue: 7)
+        let aes = AES(key: key, iv: iv, blockMode: .CBC)
         measureMetrics([XCTPerformanceMetric_WallClockTime], automaticallyStartMeasuring: true, forBlock: { () -> Void in
-            try! AES(key: key, iv: iv, blockMode: .CBC)?.decrypt(message, padding: PKCS7())
+            try! aes?.decrypt(message, padding: PKCS7())
         })
     }