swift 3.0 中的 Sha 256 加密语法错误答案

【问题标题】：Sha 256 Encryption syntax error in swift 3.0swift 3.0 中的 Sha 256 加密语法错误
【发布时间】：2016-10-07 15:42:21
【问题描述】：

    func SHA256() -> String {

    let data = self.data(using: String.Encoding.utf8)
    let res = NSMutableData(length: Int(CC_SHA256_DIGEST_LENGTH))
    CC_SHA256((data! as NSData).bytes, CC_LONG(data!.count), UnsafeMutablePointer(res!.mutableBytes))
    let hashedString = "\(res!)".replacingOccurrences(of: "", with: "").replacingOccurrences(of: " ", with: "")
    let badchar: CharacterSet = CharacterSet(charactersIn: "\"<\",\">\"")
    let cleanedstring: String = (hashedString.components(separatedBy: badchar) as NSArray).componentsJoined(by: "")
    return cleanedstring

}

我正在使用这个函数来加密它在 swift 2 中运行良好的字符串，现在它不能在 swift 3.0 中工作

【问题讨论】：

stackoverflow.com/questions/25388747/sha256-in-swift ?
或者这个是一个String to String函数：stackoverflow.com/questions/25761344/…，它可以很容易地适应SHA256。
SHA256，实际上所有的哈希函数都不是加密的，它们是单向哈希函数。

标签： ios xcode swift3

【解决方案1】：

完美解决方案 Swift 3+：

 extension String {

    // MARK: - SHA256
    func get_sha256_String() -> String {
        guard let data = self.data(using: .utf8) else {
            print("Data not available")
            return ""
        }
        return getHexString(fromData: digest(input: data as NSData))
    }

    private func digest(input : NSData) -> NSData {
        let digestLength = Int(CC_SHA256_DIGEST_LENGTH)
        var hashValue = [UInt8](repeating: 0, count: digestLength)
        CC_SHA256(input.bytes, UInt32(input.length), &hashValue)
        return NSData(bytes: hashValue, length: digestLength)
    }

    private  func getHexString(fromData data: NSData) -> String {
        var bytes = [UInt8](repeating: 0, count: data.length)
        data.getBytes(&bytes, length: data.length)

        var hexString = ""
        for byte in bytes {
            hexString += String(format:"%02x", UInt8(byte))
        }
        return hexString
    }
}

使用方法：

let desiredSHA256 = "yourString".get_sha256_String()

【讨论】：

【解决方案2】：

func sha256(string: String) -> Data? {
    guard let messageData = string.data(using:String.Encoding.utf8) else { return nil; }
   var digestData = Data(count: Int(CC_SHA256_DIGEST_LENGTH))

    _ = digestData.withUnsafeMutableBytes {digestBytes in
        messageData.withUnsafeBytes {messageBytes in
            CC_SHA256(messageBytes, CC_LONG(messageData.count), digestBytes)
        }
    }
    return digestData
}

例子：

let testString = "sha me"
print("testString: \(testString)")
let shaData = sha256(string: testString)
let shaHex = shaData!.map { String(format: "%02hhx", $0) }.joined()
print("shaHex: \(shaHex)")

输出：

testString: sha me
shaData: a60e0eee 30a3a4f1 c4f8b93f 16ad22cb 0339447b 1653f331 edbda55f eee00789

新功能是 .withUnsafeMutableBytes 闭包。

【讨论】：

【解决方案3】：

func SHA256() -> String {

    let data = self.data(using: String.Encoding.utf8)
    let res = NSMutableData(length: Int(CC_SHA256_DIGEST_LENGTH))
    CC_SHA256(((data! as NSData)).bytes, CC_LONG(data!.count), res?.mutableBytes.assumingMemoryBound(to: UInt8.self))
    let hashedString = "\(res!)".replacingOccurrences(of: "", with: "").replacingOccurrences(of: " ", with: "")
    let badchar: CharacterSet = CharacterSet(charactersIn: "\"<\",\">\"")
    let cleanedstring: String = (hashedString.components(separatedBy: badchar) as NSArray).componentsJoined(by: "")
    return cleanedstring

}

替换了 CC_SHA256((data! as NSData).bytes, CC_LONG(data!.count), UnsafeMutablePointer(res!.mutableBytes))

【讨论】：

请格式化您的代码，尤其是在将其添加到网站时。这只是不可读、执行不力的文本代码墙。 ...这是做什么的....replacingOccurrences(of: "", with: "")?
Use of unresolved identifier 'CC_SHA256_DIGEST_LENGTH' Use of unresolved identifier 'CC_SHA256' 这些错误显示给我
@RajAnjana 这是 Swift，而不是 Objective-C。
@Alejandro Iván - 是的，我接受了。但等效的标题不存在。所以我只是将该标题导入到我的 Bridge 文件中。只有它对我有用之后