Merge pull request #134 from kishikawakatsumi/md4

Replace CommonCrypto MD4 function
kishikawakatsumi · Sep 18, 2024 · 7bbeef3 · 7bbeef3
2 parents a6151cf + 3d0e090
commit 7bbeef3
Showing 1 changed file with 116 additions and 4 deletions.
diff --git a/Sources/SMBClient/Auth/Crypto.swift b/Sources/SMBClient/Auth/Crypto.swift
@@ -9,11 +9,123 @@ enum Crypto {
   }
 
   public static func md4(_ data: Data) -> Data {
-    var hash = [UInt8](repeating: 0, count: Int(CC_MD4_DIGEST_LENGTH))
-    _ = data.withUnsafeBytes { (bytes) in
-      CC_MD4(bytes.baseAddress, CC_LONG(data.count), &hash)
+    var paddedData = data
+
+    let messageLengthBits = UInt64(data.count * 8)
+
+    paddedData.append(0x80)
+
+    let messageLengthMod64 = paddedData.count % 64
+    let padLength = messageLengthMod64 < 56 ? 56 - messageLengthMod64 : 120 - messageLengthMod64
+
+    if padLength > 0 {
+      paddedData.append(contentsOf: [UInt8](repeating: 0, count: padLength))
     }
-    return Data(hash)
+
+    var lengthBytes = messageLengthBits.littleEndian
+    withUnsafeBytes(of: &lengthBytes) { paddedData.append(contentsOf: $0) }
+
+    var A: UInt32 = 0x67452301
+    var B: UInt32 = 0xefcdab89
+    var C: UInt32 = 0x98badcfe
+    var D: UInt32 = 0x10325476
+
+    let blockCount = paddedData.count / 64
+    for i in 0..<blockCount {
+      var X = [UInt32](repeating: 0, count: 16)
+      for j in 0..<16 {
+        let start = i * 64 + j * 4
+        let wordBytes = paddedData.subdata(in: start..<start+4)
+        X[j] = wordBytes.withUnsafeBytes { $0.load(as: UInt32.self).littleEndian }
+      }
+
+      let AA = A
+      let BB = B
+      let CC = C
+      let DD = D
+
+      func F(_ x: UInt32, _ y: UInt32, _ z: UInt32) -> UInt32 {
+        return (x & y) | (~x & z)
+      }
+
+      func G(_ x: UInt32, _ y: UInt32, _ z: UInt32) -> UInt32 {
+        return (x & y) | (x & z) | (y & z)
+      }
+
+      func H(_ x: UInt32, _ y: UInt32, _ z: UInt32) -> UInt32 {
+        return x ^ y ^ z
+      }
+
+      func leftRotate(_ x: UInt32, by n: UInt32) -> UInt32 {
+        return (x << n) | (x >> (32 - n))
+      }
+
+      A = leftRotate(A &+ F(B, C, D) &+ X[0], by: 3)
+      D = leftRotate(D &+ F(A, B, C) &+ X[1], by: 7)
+      C = leftRotate(C &+ F(D, A, B) &+ X[2], by: 11)
+      B = leftRotate(B &+ F(C, D, A) &+ X[3], by: 19)
+      A = leftRotate(A &+ F(B, C, D) &+ X[4], by: 3)
+      D = leftRotate(D &+ F(A, B, C) &+ X[5], by: 7)
+      C = leftRotate(C &+ F(D, A, B) &+ X[6], by: 11)
+      B = leftRotate(B &+ F(C, D, A) &+ X[7], by: 19)
+      A = leftRotate(A &+ F(B, C, D) &+ X[8], by: 3)
+      D = leftRotate(D &+ F(A, B, C) &+ X[9], by: 7)
+      C = leftRotate(C &+ F(D, A, B) &+ X[10], by: 11)
+      B = leftRotate(B &+ F(C, D, A) &+ X[11], by: 19)
+      A = leftRotate(A &+ F(B, C, D) &+ X[12], by: 3)
+      D = leftRotate(D &+ F(A, B, C) &+ X[13], by: 7)
+      C = leftRotate(C &+ F(D, A, B) &+ X[14], by: 11)
+      B = leftRotate(B &+ F(C, D, A) &+ X[15], by: 19)
+
+      let k2: UInt32 = 0x5a827999
+      A = leftRotate(A &+ G(B, C, D) &+ X[0] &+ k2, by: 3)
+      D = leftRotate(D &+ G(A, B, C) &+ X[4] &+ k2, by: 5)
+      C = leftRotate(C &+ G(D, A, B) &+ X[8] &+ k2, by: 9)
+      B = leftRotate(B &+ G(C, D, A) &+ X[12] &+ k2, by: 13)
+      A = leftRotate(A &+ G(B, C, D) &+ X[1] &+ k2, by: 3)
+      D = leftRotate(D &+ G(A, B, C) &+ X[5] &+ k2, by: 5)
+      C = leftRotate(C &+ G(D, A, B) &+ X[9] &+ k2, by: 9)
+      B = leftRotate(B &+ G(C, D, A) &+ X[13] &+ k2, by: 13)
+      A = leftRotate(A &+ G(B, C, D) &+ X[2] &+ k2, by: 3)
+      D = leftRotate(D &+ G(A, B, C) &+ X[6] &+ k2, by: 5)
+      C = leftRotate(C &+ G(D, A, B) &+ X[10] &+ k2, by: 9)
+      B = leftRotate(B &+ G(C, D, A) &+ X[14] &+ k2, by: 13)
+      A = leftRotate(A &+ G(B, C, D) &+ X[3] &+ k2, by: 3)
+      D = leftRotate(D &+ G(A, B, C) &+ X[7] &+ k2, by: 5)
+      C = leftRotate(C &+ G(D, A, B) &+ X[11] &+ k2, by: 9)
+      B = leftRotate(B &+ G(C, D, A) &+ X[15] &+ k2, by: 13)
+
+      let k3: UInt32 = 0x6ed9eba1
+      A = leftRotate(A &+ H(B, C, D) &+ X[0] &+ k3, by: 3)
+      D = leftRotate(D &+ H(A, B, C) &+ X[8] &+ k3, by: 9)
+      C = leftRotate(C &+ H(D, A, B) &+ X[4] &+ k3, by: 11)
+      B = leftRotate(B &+ H(C, D, A) &+ X[12] &+ k3, by: 15)
+      A = leftRotate(A &+ H(B, C, D) &+ X[2] &+ k3, by: 3)
+      D = leftRotate(D &+ H(A, B, C) &+ X[10] &+ k3, by: 9)
+      C = leftRotate(C &+ H(D, A, B) &+ X[6] &+ k3, by: 11)
+      B = leftRotate(B &+ H(C, D, A) &+ X[14] &+ k3, by: 15)
+      A = leftRotate(A &+ H(B, C, D) &+ X[1] &+ k3, by: 3)
+      D = leftRotate(D &+ H(A, B, C) &+ X[9] &+ k3, by: 9)
+      C = leftRotate(C &+ H(D, A, B) &+ X[5] &+ k3, by: 11)
+      B = leftRotate(B &+ H(C, D, A) &+ X[13] &+ k3, by: 15)
+      A = leftRotate(A &+ H(B, C, D) &+ X[3] &+ k3, by: 3)
+      D = leftRotate(D &+ H(A, B, C) &+ X[11] &+ k3, by: 9)
+      C = leftRotate(C &+ H(D, A, B) &+ X[7] &+ k3, by: 11)
+      B = leftRotate(B &+ H(C, D, A) &+ X[15] &+ k3, by: 15)
+
+      A = A &+ AA
+      B = B &+ BB
+      C = C &+ CC
+      D = D &+ DD
+    }
+
+    var digest = Data()
+    withUnsafeBytes(of: A.littleEndian) { digest.append(contentsOf: $0) }
+    withUnsafeBytes(of: B.littleEndian) { digest.append(contentsOf: $0) }
+    withUnsafeBytes(of: C.littleEndian) { digest.append(contentsOf: $0) }
+    withUnsafeBytes(of: D.littleEndian) { digest.append(contentsOf: $0) }
+
+    return digest
   }
 
   public static func hmacMD5(key: Data, data: Data) -> Data {