Spring Security Oauth2 之 架构源码解读

本篇追踪源码阐述获Security的认证的基本流程 

密码模式请求/oauth/token ,获取令牌（access_token）

经过客户端认证核心过滤器ClientCredentialsTokenEndpointFilter(attemptAuthentication)    

获取clientId,clientSecret组装成一个UsernamePasswordAuthenticationToken作为身份标识,经过容器中的认证管理器 AuthenticationManager 进行身份认证。AuthenticationManager 核心实现由ProviderManager完成。

public interface AuthenticationManager {
	Authentication authenticate(Authentication authentication)
			throws AuthenticationException;
}

   ProviderManager内部管理一系列真正的身份认证AuthenticationProvider，ProviderManager利用反射 根据选择参数类型对应的provider。

    result = provider.authenticate(authentication);

而AuthenticationProvider的常用实现类则是DaoAuthenticationProvider，此处DaoAuthenticationProvider调用父类AbstractUserDetailsAuthenticationProvider的authentic方法。

AbstractUserDetailsAuthenticationProvider执行子类DaoAuthenticationProvider的retrieveUser方法。

DaoAuthenticationProvider内部又聚合了一个UserDetailsService接口，UserDetailsService才是获取用户详细信息的最终接口

这边调用UserDetailsService的一个实现类ClientDetailsUserDetailsService 查询 ClientDetails 信息，这个设计是将client客户端的信息（client_id,client_secret）适配成用户的信息(username,password)。

获取完信息后，开始认证流程

然后进入 AbstractUserDetailsAuthenticationProvider 验证 信息是否可用，过期

之后，再次进如DaoAuthenticationProvider 认证clientId和clientSecret

再次进入 AbstractUserDetailsAuthenticationProvider 验证 是否过期

....  这边就不一一阐述了

UML类图

 经过认证后，请求TokenEndpoint 端点

    

根据clientId查询client具体信息
工厂模式创建TokenRequest

校验params：授权码模式必传code；刷新令牌必传refresh_token等

源码：

@FrameworkEndpoint
public class TokenEndpoint extends AbstractEndpoint {

	private OAuth2RequestValidator oAuth2RequestValidator = new DefaultOAuth2RequestValidator();

	private Set<HttpMethod> allowedRequestMethods = new HashSet<HttpMethod>(Arrays.asList(HttpMethod.POST));

	@RequestMapping(value = "/oauth/token", method=RequestMethod.GET)
	public ResponseEntity<OAuth2AccessToken> getAccessToken(Principal principal, @RequestParam
	Map<String, String> parameters) throws HttpRequestMethodNotSupportedException {
		if (!allowedRequestMethods.contains(HttpMethod.GET)) {
			throw new HttpRequestMethodNotSupportedException("GET");
		}
		return postAccessToken(principal, parameters);
	}
	
	@RequestMapping(value = "/oauth/token", method=RequestMethod.POST)
	public ResponseEntity<OAuth2AccessToken> postAccessToken(Principal principal, @RequestParam
	Map<String, String> parameters) throws HttpRequestMethodNotSupportedException {

		if (!(principal instanceof Authentication)) {
			throw new InsufficientAuthenticationException(
					"There is no client authentication. Try adding an appropriate authentication filter.");
		}

		String clientId = getClientId(principal);
		ClientDetails authenticatedClient = getClientDetailsService().loadClientByClientId(clientId);

		TokenRequest tokenRequest = getOAuth2RequestFactory().createTokenRequest(parameters, authenticatedClient);

		if (clientId != null && !clientId.equals("")) {
			// Only validate the client details if a client authenticated during this
			// request.
			if (!clientId.equals(tokenRequest.getClientId())) {
				// double check to make sure that the client ID in the token request is the same as that in the
				// authenticated client
				throw new InvalidClientException("Given client ID does not match authenticated client");
			}
		}
		if (authenticatedClient != null) {
			oAuth2RequestValidator.validateScope(tokenRequest, authenticatedClient);
		}
		if (!StringUtils.hasText(tokenRequest.getGrantType())) {
			throw new InvalidRequestException("Missing grant type");
		}
		if (tokenRequest.getGrantType().equals("implicit")) {
			throw new InvalidGrantException("Implicit grant type not supported from token endpoint");
		}

		if (isAuthCodeRequest(parameters)) {
			// The scope was requested or determined during the authorization step
			if (!tokenRequest.getScope().isEmpty()) {
				logger.debug("Clearing scope of incoming token request");
				tokenRequest.setScope(Collections.<String> emptySet());
			}
		}

		if (isRefreshTokenRequest(parameters)) {
			// A refresh token has its own default scopes, so we should ignore any added by the factory here.
			tokenRequest.setScope(OAuth2Utils.parseParameterList(parameters.get(OAuth2Utils.SCOPE)));
		}

		OAuth2AccessToken token = getTokenGranter().grant(tokenRequest.getGrantType(), tokenRequest);
		if (token == null) {
			throw new UnsupportedGrantTypeException("Unsupported grant type: " + tokenRequest.getGrantType());
		}

		return getResponse(token);

	}

	....
}

调用接口TokenGranter构建令牌OAuth2AccessToken

public interface TokenGranter {

	OAuth2AccessToken grant(String grantType, TokenRequest tokenRequest);

}

调用CompositeTokenGranter，获取相对应的TokenGranter（共五种）
ResourceOwnerPasswordTokenGranter     password密码模式
AuthorizationCodeTokenGranter               authorization_code授权码模式
ClientCredentialsTokenGranter                  client_credentials客户端模式
ImplicitTokenGranter                                  implicit简化模式 
RefreshTokenGranter                                 refresh_token 刷新token

public class CompositeTokenGranter implements TokenGranter {

	private final List<TokenGranter> tokenGranters;

	public CompositeTokenGranter(List<TokenGranter> tokenGranters) {
		this.tokenGranters = new ArrayList<TokenGranter>(tokenGranters);
	}
	
	public OAuth2AccessToken grant(String grantType, TokenRequest tokenRequest) {
		for (TokenGranter granter : tokenGranters) {
			OAuth2AccessToken grant = granter.grant(grantType, tokenRequest);
			if (grant!=null) {
				return grant;
			}
		}
		return null;
	}
	
	public void addTokenGranter(TokenGranter tokenGranter) {
		if (tokenGranter == null) {
			throw new IllegalArgumentException("Token granter is null");
		}
		tokenGranters.add(tokenGranter);
	}

}

 AbstractTokenGranter根据 grantType选择对应TokenGranter 调用子类的getAccessToken

public OAuth2AccessToken grant(String grantType, TokenRequest tokenRequest) {

		if (!this.grantType.equals(grantType)) {
			return null;
		}
		
		String clientId = tokenRequest.getClientId();
		ClientDetails client = clientDetailsService.loadClientByClientId(clientId);
		validateGrantType(grantType, client);
		
		logger.debug("Getting access token for: " + clientId);

		return getAccessToken(client, tokenRequest);

	}

密码模式调用ResourceOwnerPasswordTokenGranter 校验username,password流程和clientId,clientSecret一致，区别于UserDetailsService实现类是JdbcDaoImpl。

调用AuthorizationServerTokenServices.createAccessToken 创建 OAuth2AccessToken

public interface AuthorizationServerTokenServices {

	/**
	 * Create an access token associated with the specified credentials.
	 * @param authentication The credentials associated with the access token.
	 * @return The access token.
	 * @throws AuthenticationException If the credentials are inadequate.
	 */
	OAuth2AccessToken createAccessToken(OAuth2Authentication authentication) throws AuthenticationException;

	/**
	 * Refresh an access token. The authorization request should be used for 2 things (at least): to validate that the
	 * client id of the original access token is the same as the one requesting the refresh, and to narrow the scopes
	 * (if provided).
	 * 
	 * @param refreshToken The details about the refresh token.
	 * @param tokenRequest The incoming token request.
	 * @return The (new) access token.
	 * @throws AuthenticationException If the refresh token is invalid or expired.
	 */
	OAuth2AccessToken refreshAccessToken(String refreshToken, TokenRequest tokenRequest)
			throws AuthenticationException;

	/**
	 * Retrieve an access token stored against the provided authentication key, if it exists.
	 * 
	 * @param authentication the authentication key for the access token
	 * 
	 * @return the access token or null if there was none
	 */
	OAuth2AccessToken getAccessToken(OAuth2Authentication authentication);

}

public class DefaultTokenServices implements AuthorizationServerTokenServices, ResourceServerTokenServices,
		ConsumerTokenServices, InitializingBean {

	private int refreshTokenValiditySeconds = 60 * 60 * 24 * 30; // default 30 days.

	private int accessTokenValiditySeconds = 60 * 60 * 12; // default 12 hours.

	private boolean supportRefreshToken = false;

	private boolean reuseRefreshToken = true;

	private TokenStore tokenStore;

	private ClientDetailsService clientDetailsService;

	private TokenEnhancer accessTokenEnhancer;

	private AuthenticationManager authenticationManager;

	/**
	 * Initialize these token services. If no random generator is set, one will be created.
	 */
	public void afterPropertiesSet() throws Exception {
		Assert.notNull(tokenStore, "tokenStore must be set");
	}

	@Transactional
	public OAuth2AccessToken createAccessToken(OAuth2Authentication authentication) throws AuthenticationException {

		OAuth2AccessToken existingAccessToken = tokenStore.getAccessToken(authentication);
		OAuth2RefreshToken refreshToken = null;
		if (existingAccessToken != null) {
			if (existingAccessToken.isExpired()) {
				if (existingAccessToken.getRefreshToken() != null) {
					refreshToken = existingAccessToken.getRefreshToken();
					// The token store could remove the refresh token when the
					// access token is removed, but we want to
					// be sure...
					tokenStore.removeRefreshToken(refreshToken);
				}
				tokenStore.removeAccessToken(existingAccessToken);
			}
			else {
				// Re-store the access token in case the authentication has changed
				tokenStore.storeAccessToken(existingAccessToken, authentication);
				return existingAccessToken;
			}
		}

		// Only create a new refresh token if there wasn't an existing one
		// associated with an expired access token.
		// Clients might be holding existing refresh tokens, so we re-use it in
		// the case that the old access token
		// expired.
		if (refreshToken == null) {
			refreshToken = createRefreshToken(authentication);
		}
		// But the refresh token itself might need to be re-issued if it has
		// expired.
		else if (refreshToken instanceof ExpiringOAuth2RefreshToken) {
			ExpiringOAuth2RefreshToken expiring = (ExpiringOAuth2RefreshToken) refreshToken;
			if (System.currentTimeMillis() > expiring.getExpiration().getTime()) {
				refreshToken = createRefreshToken(authentication);
			}
		}

		OAuth2AccessToken accessToken = createAccessToken(authentication, refreshToken);
		tokenStore.storeAccessToken(accessToken, authentication);
		// In case it was modified
		refreshToken = accessToken.getRefreshToken();
		if (refreshToken != null) {
			tokenStore.storeRefreshToken(refreshToken, authentication);
		}
		return accessToken;

	}

tokenStore (四种)：
InMemoryTokenStore   基于内存
JdbcTokenStore            基于数据库
JwtTokenStore              基于Jwt
RedisTokenStore           基于redis

userDetailsService，tokenStore 等一些配置化信息，下一篇详解