de.is24.aws.instancemetadataserver.SecurityCredentialsController.java Source code

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Here is the source code for de.is24.aws.instancemetadataserver.SecurityCredentialsController.java

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/**
 * AWS Instance Metadata Server
 * Copyright 2015 Immobilien Scout GmbH
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package de.is24.aws.instancemetadataserver;

import com.amazonaws.services.identitymanagement.model.GetRoleRequest;
import com.amazonaws.services.identitymanagement.model.NoSuchEntityException;
import com.amazonaws.services.identitymanagement.model.Role;
import com.amazonaws.services.securitytoken.model.AssumeRoleRequest;
import com.amazonaws.services.securitytoken.model.Credentials;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

import javax.servlet.http.HttpServletRequest;
import java.util.HashMap;
import java.util.Map;
import java.util.Optional;

import java.text.SimpleDateFormat;
import java.util.TimeZone;

import static org.springframework.http.HttpStatus.NOT_FOUND;

@Controller
@RequestMapping(value = "/{version}/meta-data/iam/security-credentials", method = RequestMethod.GET)
public class SecurityCredentialsController {

    private static TimeZone tz = TimeZone.getTimeZone("UTC");
    private static SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'");

    private static final Logger LOG = LoggerFactory.getLogger(SecurityCredentialsController.class);
    private static final ResponseEntity<Map<String, String>> HTTP_NOT_FOUND = new ResponseEntity<>(NOT_FOUND);

    private final RoleNameProducer roleNameProducer;
    private final AwsClientFactory awsClientFactory;

    static {
        df.setTimeZone(tz);
    }

    @Autowired
    public SecurityCredentialsController(RoleNameProducer roleNameProducer, AwsClientFactory awsClientFactory) {
        this.roleNameProducer = roleNameProducer;
        this.awsClientFactory = awsClientFactory;
    }

    @RequestMapping
    @ResponseBody
    public String list(HttpServletRequest request) {
        return allowedRoleName(request).flatMap(this::getAwsRole).map(Role::getRoleName).orElse("");
    }

    @RequestMapping("/{requestedRoleName}")
    public ResponseEntity<Map<String, String>> credential(HttpServletRequest request,
            @PathVariable String requestedRoleName) {
        return allowedRoleName(request).filter(requestedRoleName::equals).flatMap(this::getAwsRole)
                .map(this::assumeRole).map((r) -> {
                    LOG.info("Assumed role {} for {} valid till {}", requestedRoleName, request.getRemoteHost(),
                            df.format(r.getExpiration()));
                    return r;
                }).map(this::asJson).map(ResponseEntity::ok).orElse(HTTP_NOT_FOUND);
    }

    private Optional<String> allowedRoleName(HttpServletRequest request) {
        return roleNameProducer.getRoleName(request);
    }

    private Optional<Role> getAwsRole(String roleName) {
        try {
            return Optional.of(awsClientFactory.amazonIdentityManagement()
                    .getRole(new GetRoleRequest().withRoleName(roleName)).getRole());
        } catch (NoSuchEntityException e) {
            LOG.info("No AWS role named '{}' exists", roleName);
            return Optional.empty();
        }
    }

    private Credentials assumeRole(Role role) {
        return awsClientFactory.awsSecurityTokenService()
                .assumeRole(
                        new AssumeRoleRequest().withRoleSessionName(role.getRoleName()).withRoleArn(role.getArn()))
                .getCredentials();
    }

    private Map<String, String> asJson(Credentials credentials) {
        Map<String, String> json = new HashMap<String, String>();
        json.put("AccessKeyId", credentials.getAccessKeyId());
        json.put("SecretAccessKey", credentials.getSecretAccessKey());
        json.put("Token", credentials.getSessionToken());
        json.put("Expiration", df.format(credentials.getExpiration()));
        json.put("Code", "Success");
        json.put("Type", "AWS-HMAC");

        return json;
    }
}