我有同样的问题，我发现我提供的证书.crt文件缺少一个中间证书。所以我从我的服务器管理员那里询问了所有的.crt文件，然后按相反的顺序将它们连接起来。

前女友。 1. crt 2. Inter.crt 3.myCrt.crt

在Windows中执行 复制国际米兰。crt + Root。crt newCertificate.crt

(这里我忽略了myCrt.crt)

然后我提供了newCertificate。CRT文件通过输入流转换成代码。 工作。

我得到的错误消息与此类似，但原因是自签名证书已经过期。 当尝试openssl客户端时，它给了我一个原因，当我在firefox中检查证书对话框时忽略了这个原因。

因此，通常情况下，如果证书在密钥存储库中并且它是“VALID”，则此错误将消失。

In my case, the root & intermediate certificates was successfully installed but I still got "Trust anchor for certification path not found." exception!. After digging the android document, found out that by default, secure connections (using protocols like TLS and HTTPS) from all apps trust the pre-installed system CAs, and apps targeting Android 6.0 (API level 23) and lower also trust the user-added CA store by default. If your app running on a OS with api level higher than 23 you should explicitly allow the app to trust user-added CA by adding its address to network_security_config like bellow:

<domain-config>
        <domain includeSubdomains="true">PUT_YOUR_SERVER_ADDERESS</domain>
        <trust-anchors>
            <certificates src="user" />
        </trust-anchors>
</domain-config>

产生信任锚错误的原因有很多。对我来说，我只是想访问https://example.com/而不是https://www.example.com/。

因此，在开始构建自己的信任管理器(就像我做的那样)之前，您可能需要仔细检查您的url。

我也遇到过类似的问题，我已经完全排除了相信所有消息来源的策略。

我在这里分享我在Kotlin中实现的应用程序中的解决方案

我首先建议使用以下网站获取有关证书及其有效性的信息

如果它不在Android默认信任存储中显示为“已接受的发行者”，我们必须获得该证书并将其合并到应用程序中以创建自定义信任存储

在我的案例中，理想的解决方案是创建一个高级信任管理器，它结合了自定义和Android默认信任存储

在这里，他公开了用于配置他与Retrofit一起使用的OkHttpClient的高级代码。

override fun onBuildHttpClient(httpClientBuild: OkHttpClient.Builder) {

        val trustManagerWrapper = createX509TrustManagerWrapper(
            arrayOf(
                getCustomX509TrustManager(),
                getDefaultX509TrustManager()
            )
        )

        printX509TrustManagerAcceptedIssuers(trustManagerWrapper)

        val sslSocketFactory = createSocketFactory(trustManagerWrapper)
        httpClientBuild.sslSocketFactory(sslSocketFactory, trustManagerWrapper)

    }

通过这种方式，我可以使用自签名证书与服务器通信，也可以使用受信任的证书实体颁发的证书与其他服务器通信

就是这个，我希望它能帮助到一些人。

使用https://www.ssllabs.com/ssltest/测试域。

Shihab Uddin在Kotlin的解决方案。

import java.security.SecureRandom
import java.security.cert.X509Certificate
import javax.net.ssl.*
import javax.security.cert.CertificateException

object {

    val okHttpClient: OkHttpClient
    val gson: Gson
    val retrofit: Retrofit

    init {

        okHttpClient = getOkHttpBuilder()
            // Other parameters like connectTimeout(15, TimeUnit.SECONDS)
            .build()

        gson = GsonBuilder().setLenient().create()

        retrofit = Retrofit.Builder()
            .baseUrl(BASE_URL)
            .client(okHttpClient)
            .addConverterFactory(GsonConverterFactory.create(gson))
            .build()
    }

    fun getOkHttpBuilder(): OkHttpClient.Builder =
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            OkHttpClient().newBuilder()
        } else {
            // Workaround for the error "Caused by: com.android.org.bouncycastle.jce.exception.ExtCertPathValidatorException: Could not validate certificate: Certificate expired at".
            getUnsafeOkHttpClient()
        }

    private fun getUnsafeOkHttpClient(): OkHttpClient.Builder =
        try {
            // Create a trust manager that does not validate certificate chains
            val trustAllCerts: Array<TrustManager> = arrayOf(
                object : X509TrustManager {
                    @Throws(CertificateException::class)
                    override fun checkClientTrusted(chain: Array<X509Certificate?>?,
                                                    authType: String?) = Unit

                    @Throws(CertificateException::class)
                    override fun checkServerTrusted(chain: Array<X509Certificate?>?,
                                                    authType: String?) = Unit

                    override fun getAcceptedIssuers(): Array<X509Certificate> = arrayOf()
                }
            )
            // Install the all-trusting trust manager
            val sslContext: SSLContext = SSLContext.getInstance("SSL")
            sslContext.init(null, trustAllCerts, SecureRandom())
            // Create an ssl socket factory with our all-trusting manager
            val sslSocketFactory: SSLSocketFactory = sslContext.socketFactory
            val builder = OkHttpClient.Builder()
            builder.sslSocketFactory(sslSocketFactory,
                trustAllCerts[0] as X509TrustManager)
            builder.hostnameVerifier { _, _ -> true }
            builder
        } catch (e: Exception) {
            throw RuntimeException(e)
        }
}

如果你使用Glide，同样的错误也会出现，图像不会显示。要克服它，请参阅Glide - javax.net.ssl.SSLHandshakeException: java.security. cert.certpathvalidatorexcexception:未找到认证路径的信任锚以及如何为Glide设置OkHttpClient。

@GlideModule
class MyAppGlideModule : AppGlideModule() {

    val okHttpClient = Api.getOkHttpBuilder().build() // Api is the class written above.
    // It is better to create okHttpClient here and not use Api.okHttpClient,
    // because their settings may differ. For instance, it can use its own
    // `addInterceptor` and `addNetworkInterceptor` that can affect on a read JSON.


    override fun registerComponents(context: Context, glide: Glide, registry: Registry) {
        registry.replace(GlideUrl::class.java, InputStream::class.java,
            OkHttpUrlLoader.Factory(okHttpClient))
    }
}

build.gradle:

// Glide.
implementation 'com.github.bumptech.glide:glide:4.11.0'
implementation 'com.github.bumptech.glide:okhttp3-integration:4.11.0'
kapt 'com.github.bumptech.glide:compiler:4.11.0'

更新

我还在API 16模拟器上得到了另一个错误:

SSL23_GET_SERVER_HELLO:tlsv1警报协议版本 (外部/ openssl / ssl / s23_clnt.c: 741”。

阅读1和2，我修改代码如下:

okHttpClient = getOkHttpBuilder().build()

private fun getOkHttpBuilder(): OkHttpClient.Builder {
    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
        Security.insertProviderAt(Conscrypt.newProvider(), 1)
    }
    return OkHttpClient().newBuilder()
}

// build.gradle:
implementation 'org.conscrypt:conscrypt-android:2.5.1'

我还从MyApplication中删除了这些行:

try {
    ProviderInstaller.installIfNeeded(applicationContext)
    val sslContext = SSLContext.getInstance("TLSv1.2")
    sslContext.init(null, null, null)
    sslContext.createSSLEngine()
} catch (e: GooglePlayServicesRepairableException) {
    Timber.e(e.stackTraceToString())
    // Prompt the user to install/update/enable Google Play services.
    GoogleApiAvailability.getInstance().showErrorNotification(this, e.connectionStatusCode)
} catch (e: GooglePlayServicesNotAvailableException) {
    Timber.e(e.stackTraceToString())
    // Prompt the user to install/update/enable Google Play services.
    // GoogleApiAvailability.getInstance().showErrorNotification(this, e.errorCode)
} catch (e: NoSuchAlgorithmException) {
    Timber.e(e.stackTraceToString())
} catch (e: KeyManagementException) {
    Timber.e(e.stackTraceToString())
}

但是这个库给apk增加了3.4 Mb。