首页 > 解决方案 > Ktor 客户端 IOS 和自签名证书

问题描述

我在访问内部开发服务器的 iOS 应用程序中在 iOS 中使用 Ktor 和 Kotlin/native。开发服务器使用由不公开信任的内部 CA 颁发的证书。

尝试使用以下代码访问服务器时:

  internal suspend fun performHttp(url : String)
    {
        // URL is a self signed HTTPS: request
        val client = HttpClient(Ios) 

        val response = client.get<String>(url)
        println(response)
    }

它抛出以下异常:

TIC SSL Trust Error [32:0x281956dc0]: 3:0
esri2[470:136341] NSURLSession/NSURLConnection HTTP load failed (kCFStreamErrorDomainSSL, -9807)
esri2[470:136341] Task <F3CC4C40-0231-4E58-97F3-F457D5A18BB0>.<1> HTTP load failed (error code: -1202 [3:-9807])
 esri2[470:136417] Task <F3CC4C40-0231-4E58-97F3-F457D5A18BB0>.<1> finished with error - code: -1202
esri2[470:136211] Task <F3CC4C40-0231-4E58-97F3-F457D5A18BB0>.<1> load failed with error Error Domain=NSURLErrorDomain Code=-1202 "The certificate for this server is invalid. You might be connecting to a server that is pretending to be “server1.internal.lan” which could put your confidential information at risk." UserInfo={NSLocalizedRecoverySuggestion=Would you like to connect to the server anyway?, _kCFStreamErrorDomainKey=3, NSErrorPeerCertificateChainKey=(
    "<cert(0x12b094e00) s: server1.internal.lan i: Internal-Issuing-CA2>",

我如何说服 Ktor 它应该访问这个 URL,或者忽略不受信任的证书?是的,我知道不应忽视不受信任的证书,但这是一项实验室测试。

标签: iossslktorkotlin-native

解决方案


Ktor iOS 引擎提供了在 IosClientEngineConfig.kt的帮助下配置底层NSURLSession的能力

有了它,您可以通过在配置中ChallengeHandler设置块来配置(除其他外)a ,如下所示:handleChallenge

val client = HttpClient(Ios) {
    engine {
        handleChallenge(TrustSelfSignedCertificate())
    }
}

然后你需要在 Kotlin 中实现一个类,如下所示:

internal data class TrustSelfSignedCertificate internal constructor(
    private val validateTrust: Boolean = true
) : ChallengeHandler {

    override fun invoke(
        session: NSURLSession,
        task: NSURLSessionTask,
        challenge: NSURLAuthenticationChallenge,
        completionHandler: (NSURLSessionAuthChallengeDisposition, NSURLCredential?) -> Unit
    ) {
        val hostname = challenge.protectionSpace.host

        val serverTrust = challenge.protectionSpace.serverTrust
        var result: SecTrustResultType = 0u

        memScoped {
            val nativeResult = alloc<SecTrustResultTypeVar>()
            nativeResult.value = result
            SecTrustEvaluate(serverTrust!!, nativeResult.ptr)
        }

        val serverCertificate = SecTrustGetCertificateAtIndex(serverTrust, 0)
        val serverCertificateData = SecCertificateCopyData(serverCertificate)
        val data = CFDataGetBytePtr(serverCertificateData)
        val size = CFDataGetLength(serverCertificateData)

        val cert1 = NSData.dataWithBytes(data, size.toULong())
        val pathToCert = NSBundle.mainBundle.pathForResource("myOwnCert", "cer")

        val localCertificate: NSData = NSData.dataWithContentsOfFile(pathToCert!!)!!

        if (localCertificate == cert1) {
            completionHandler(
                NSURLSessionAuthChallengeUseCredential,
                NSURLCredential.create(serverTrust)
            )
        } else {
            completionHandler(NSURLSessionAuthChallengeCancelAuthenticationChallenge, null)
        }
    }
}

另外,不要忘记将您的证书作为文件“myOwnCert.cer”放入您的 iOS 项目(可能在顶层)。


笔记

带有 iOS 引擎的 Ktor 不尊重/使用NSApptransportSecurity


该代码基于此答案

在这篇博文的帮助下。


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