Add AzureCC provider, call sidecar to get MAA token

pom.xml

@@ -38,6 +38,12 @@
             <artifactId>uid2-attestation-api</artifactId>
             <version>1.1.0</version>
         </dependency>
+        <dependency>
+            <groupId>com.google.code.gson</groupId>
+            <artifactId>gson</artifactId>
+            <version>2.10</version>
+            <scope>compile</scope>
+        </dependency>
     </dependencies>
 
     <distributionManagement>
@@ -57,8 +63,8 @@
                         <arg>-h</arg>
                         <arg>target/headers</arg>
                     </compilerArgs>
-                    <source>8</source>
-                    <target>8</target>
+                    <source>11</source>
+                    <target>11</target>
                 </configuration>
             </plugin>       
 	    <plugin>

src/main/java/com/uid2/attestation/azure/AzureCCAttestationProvider.java

@@ -0,0 +1,90 @@
+package com.uid2.attestation.azure;
+
+import com.uid2.enclave.AttestationException;
+import com.uid2.enclave.IAttestationProvider;
+
+import com.google.gson.Gson;
+import com.google.gson.reflect.TypeToken;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.util.Base64;
+import java.util.HashMap;
+
+public class AzureCCAttestationProvider implements IAttestationProvider {
+	private final String maaEndpoint;
+	private static final String DefaultMaaEndpoint = "sharedeus.eus.attest.azure.net";
+	private final String skrEndpoint;
+	private static final String DefaultSkrEndpoint = "http://localhost:8080/attest/maa";
+	private final HttpClient httpClient;
+
+	public AzureCCAttestationProvider() {
+		this(DefaultSkrEndpoint, DefaultMaaEndpoint, null);
+	}
+	public AzureCCAttestationProvider(String maaEndpoint) {
+		this(maaEndpoint, DefaultSkrEndpoint, null);
+	}
+
+	public AzureCCAttestationProvider(String maaEndpoint, String skrEndpoint) {
+		this(maaEndpoint, skrEndpoint, null);
+	}
+
+	public AzureCCAttestationProvider(String maaEndpoint, String skrEndpoint, HttpClient httpClient) {
+		this.maaEndpoint = maaEndpoint;
+		this.skrEndpoint = skrEndpoint;
+
+		if (httpClient != null) {
+			this.httpClient = httpClient;
+		} else {
+			this.httpClient = HttpClient.newHttpClient();
+		}
+	}
+	@Override
+	public byte[] getAttestationRequest(byte[] publicKey) throws AttestationException {
+		var base64Encoder = Base64.getEncoder();
+		var gson = new Gson();
+
+		var runtimeData = new HashMap<String, String>();
+		runtimeData.put("location", getLocation());
+		runtimeData.put("publicKey", base64Encoder.encodeToString(publicKey));
+		String runtimeDataJson = gson.toJson(runtimeData);
+
+		var body = new HashMap<String, String>();
+		body.put("maa_endpoint", this.maaEndpoint);
+		body.put("runtime_data", base64Encoder.encodeToString(runtimeDataJson.getBytes()));
+		String bodyJson = gson.toJson(body);
+
+		var request = HttpRequest.newBuilder()
+				.uri(URI.create(skrEndpoint))
+				.header("Content-Type", "application/json")
+				.POST(HttpRequest.BodyPublishers.ofString(bodyJson))
+				.build();
+
+		try {
+			HttpResponse<String> response = this.httpClient.send(request, HttpResponse.BodyHandlers.ofString());
+			if (response.statusCode() != HttpURLConnection.HTTP_OK) {
+				throw new AttestationException("Skr failed with status code: " + response.statusCode() + " body: " + response.body());
+			}
+
+			var responseBodyType = new TypeToken<HashMap<String, String>>(){};
+			var responseBody = gson.fromJson(response.body(), responseBodyType);
+			var token = responseBody.get("token");
+			if (token == null) {
+				throw new AttestationException("token field not exist in Skr response");
+			}
+			return token.getBytes();
+		} catch (IOException e) {
+			throw new AttestationException(e);
+		} catch (InterruptedException e) {
+			throw new AttestationException(e);
+		}
+	}
+
+	private String getLocation() throws AttestationException {
+		return "";
+	}
+}