ESP32 WiFiClientSecure SSL-连接指示EOF

Question

我尝试使用SSL将ESP32连接到MQTT代理。

WiFiClientSecure espClient;
MQTTClient client;

const char* mqtt_server = "a0dda4ea-dcaf-408d-...";
const char* ca_cert = \
"-----BEGIN CERTIFICATE-----\n" \
"MIIElDCCA3ygAwIBAgIQAf2j627KdciIQ4tyS8+8kTANBgkqhkiG9w0BAQsFADBh\n" \
....
"c+LJMto4JQtV05od8GiG7S5BNO98pVAdvzr508EIDObtHopYJeS4d60tbvVS3bR0\n" \
"j6tJLp07kzQoH3jOlOrHvdPJbRzeXDLz\n" \
"-----END CERTIFICATE-----\n";


const char* cert = \
"-----BEGIN CERTIFICATE-----\n" \
"MIIEbDCCA1SgAwIBAgIPAJKQXaPFq3STEAECe9IQMA0GCSqGSIb3DQEBCwUAMFYx\n" \
...
"k7QMObr9H2Pf/xzj8vWnDdshvMHXyuwELA2ExEuW/II=\n" \
"-----END CERTIFICATE-----\n";


const char* key = \
"-----BEGIN RSA PRIVATE KEY-----\n" \
"MIIEpAIBAAKCAQEA3RrsSgye/7a5vxoXQldQB1L4gg/bu3HDaIx74ojJezH0VjEi\n" \
...
"sEN+EfBNH8GA9b3T8906kkml0B3U3+qO/CUrRgaagB09xgPKIoPbog==\n" \
"-----END RSA PRIVATE KEY-----\n";

void connect() {
    Serial.print("\nconnecting...");
    while (!client.connect("fullReader", false)) {
        Serial.print(".");
        delay(5000);
    }

    Serial.println("\nconnected!");
}

void setup()
{
  Serial.begin(9600);
  SPI.begin();

  wifiManager.autoConnect("abcd");
  Serial.println("connected...yeey :)");

  espClient.setCACert(ca_cert);
  espClient.setCertificate(cert);
  espClient.setPrivateKey(key);

  client.begin(mqtt_server, 8883, espClient);
  connect();
}

不幸的是，这总是导致错误

[E][ssl_client.cpp:33] _handle_error(): [start_ssl_client():199]: (-29312) SSL - The connection indicated an EOF
[E][WiFiClientSecure.cpp:132] connect(): start_ssl_client: -29312

我已经使用MQTT客户端（MQTTBox）验证了证书和私钥是否正确。 在那里，我可以连接到代理。 您有什么想法吗？