iOS AES/CBC/CTR加解密以及AES-CMAC

感觉iOS自带的CryptoKit不好用，有个第三方库CryptoSwift还不错，好巧不巧，清理过Xcode缓存后死活下载不下来，当然也可以自己编译个Framework，但是偏偏不想用第三方库了，于是研究了一下，自带的CommonCrypto也可以达到项目需求。

代码主要包含以下算法：

AES128/CBC/NoPadding

AES128/CTR/NoPadding

AES-CMAC

import Foundation
import CommonCryptoclass AESUtil {private init(){}//////AES-CMAC///static func CMAC(key: Data, data: Data) -> Data? {let blockSize = 16var subKey1 = Data(count: blockSize)var subKey2 = Data(count: blockSize)// Step 1: Generate subkeysguard generateSubKeys(key: key, subKey1: &subKey1, subKey2: &subKey2) else {return nil}// Step 2: Calculate the number of blockslet blockCount = (data.count + blockSize - 1) / blockSize// Step 3: Process each blockvar lastBlock = Data(count: blockSize)for i in 0..<blockCount {let blockRange = i * blockSize..<min((i + 1) * blockSize, data.count)var block = data.subdata(in: blockRange)if i == blockCount - 1 {if block.count < blockSize {block.append(0x80)while block.count < blockSize {block.append(0x00)}block = xor(data: block, with: subKey2)} else {block = xor(data: block, with: subKey1)}}lastBlock = xor(data: lastBlock, with: block)lastBlock = CBC(key: key, data: lastBlock, isEncrypt: true)!}return lastBlock}private static func generateSubKeys(key: Data, subKey1: inout Data, subKey2: inout Data) -> Bool {let blockSize = 16let zeroBlock = Data(count: blockSize)guard let L = CBC(key: key, data: zeroBlock, isEncrypt: true) else {return false}subKey1 = generateSubKey(block: L)subKey2 = generateSubKey(block: subKey1)return true}private static func generateSubKey(block: Data) -> Data {let blockSize = 16var subKey = Data(count: 16)var overflow = falsefor i in (0..<blockSize).reversed() {let byte = block[i]let shiftedByte = byte << 1subKey[i] = shiftedByte | (overflow ? 1 : 0)overflow = (byte & 0x80) != 0}if overflow {subKey[blockSize - 1] ^= 0x87}return subKey}private static func xor(data: Data, with other: Data) -> Data {var result = Data(count: data.count)for i in 0..<data.count {result[i] = data[i] ^ other[i]}return result}//////AES128/CBC/NoPadding加解密//////@param isEncrypt true加密，false解密///static func CBC(key: Data, data: Data, isEncrypt: Bool) -> Data? {return AES128NoPadding(key: key, iv: Data(count: 16), data: data, mode: "CBC", isEncrypt: isEncrypt)}//////AES128/CTR/NoPadding加解密//////@param isEncrypt true加密，false解密///static func CTR(key: Data, data: Data, isEncrypt: Bool) -> Data? {return AES128NoPadding(key: key, iv: Data(count: 16), data: data, mode: "CTR", isEncrypt: isEncrypt)}//////AES128/NoPadding加解密//////@param mode 支持CBC、CTR///@param isEncrypt true加密，false解密///static func AES128NoPadding(key: Data, iv: Data, data: Data, mode: String, isEncrypt: Bool) -> Data? {let bufferLength = data.count + kCCKeySizeAES128var buffer = Data(count: bufferLength)var numBytesEncrypted: size_t = 0let operation = isEncrypt ? kCCEncrypt : kCCDecryptlet cryptStatus: CCCryptorStatus = buffer.withUnsafeMutableBytes { (bufferPtr: UnsafeMutableRawBufferPointer) inkey.withUnsafeBytes { (keyPtr: UnsafeRawBufferPointer) iniv.withUnsafeBytes { (ivPtr: UnsafeRawBufferPointer) indata.withUnsafeBytes { (dataPtr: UnsafeRawBufferPointer) in//调用加密函数var modeSource = 0if mode == "CBC" {modeSource = kCCModeCBC} else if mode == "CTR" {modeSource = kCCModeCTR}let cryptorRef = UnsafeMutablePointer<CCCryptorRef?>.allocate(capacity: 1)var status = CCCryptorCreateWithMode(CCOperation(operation), CCMode(modeSource), CCAlgorithm(kCCAlgorithmAES), CCPadding(ccNoPadding), ivPtr.baseAddress, keyPtr.baseAddress, kCCKeySizeAES128, nil, 0, 0, CCModeOptions(0), cryptorRef)if status == kCCSuccess {status = CCCryptorUpdate(cryptorRef.pointee, dataPtr.baseAddress, data.count, bufferPtr.baseAddress, bufferLength, &numBytesEncrypted)} else {print("CCCryptorCreateWithMode fail: \(encryptError(status))")}return status}}}}if cryptStatus == kCCSuccess {buffer.removeSubrange(numBytesEncrypted..<bufferLength)return buffer}print("AES/\(mode)/NoPadding加解密失败: \(encryptError(cryptStatus))")return nil}private static func encryptError(_ status: CCCryptorStatus)-> String {if status == kCCParamError {return "kCCParamError"} else if status == kCCBufferTooSmall {return "kCCBufferTooSmall"} else if status == kCCMemoryFailure {return "kCCMemoryFailure"} else if status == kCCAlignmentError {return "kCCAlignmentError"} else if status == kCCDecodeError {return "kCCDecodeError"} else if status == kCCUnimplemented {return "kCCUnimplemented"} else if status == kCCOverflow {return "kCCOverflow"} else if status == kCCRNGFailure {return "kCCRNGFailure"} else if status == kCCUnspecifiedError {return "kCCUnspecifiedError"} else if status == kCCCallSequenceError {return "kCCCallSequenceError"} else if status == kCCKeySizeError {return "kCCKeySizeError"} else if status == kCCInvalidKey {return "kCCInvalidKey"}return "\(status)"}
}