协议

Token接口

oidc服务需要提供token接口，提供AccessToken,IdToken,以及RefreshToken（可选）。在授权码模式下，token接口必须使用https。

请求

必须使用POST方法，使用x-www-form-urlencoded序列化参数，clientId:clientSecret使用Basic加密放在Authorization头中

POST /token HTTP/1.1

Host: server.example.com

Content-Type: application/x-www-form-urlencoded

Authorization: Basic czZCaGRSa3F0MzpnWDFmQmF0M2JW

grant_type=authorization_code&code=SplxlOBeZQQYbYS6WxSbIA

&redirect_uri=https%3A%2F%2Fclient.example.org%2Fcb

请求校验

认证服务必须校验下列内容：

验证client是否颁发了秘钥
验证为该客户端颁发了授权码
验证授权码有效性
如果可能的话，验证授权码是否被使用过
验证redirect_uri 与发起认证请求时的值一致

成功响应

在收到token请求，并校验通过之后，认证服务返回成功报文，报文包含了身份令牌和通行令牌。数据格式使用application/json。token_type必须返回Bearer，其他类型token不在本协议范围内。在OAuth2.0响应报文基础上，oidc增加了id_tken。所有token包含了token或者其他敏感信息的响应报文，必须包含以下响应头。

Cache-Control no-store

Pragma no-cache

失败响应

如果认证失败返回application/json格式错误消息，状态码400

  HTTP/1.1 400 Bad Request

  Content-Type: application/json

  Cache-Control: no-store

  Pragma: no-cache

  {

   "error": "invalid_request"

  }

id token校验

客户端必须校验返回的id token, 校验条件如下。对照这些条件，就可以更懂Microsoft.Authentication.OpenIdConnect里面的代码了，要做的事情很多。

如果id token被加密，使用客户端注册时候约定的秘钥和算法解密。如果约定了加密方式，id token未被加密，客户端应该拒绝。
签发方标识必须与iss声明一致
客户端必须校验aud声明包含了它的客户端id，如果id token未返回正确的audience或者反悔了不被新人的audience，应该拒绝
如果id token包含多个audience，需要校验是否有azp声明。azp即Authorized party，标识被授权的client。
如果包含azp声明，客户端需要校验其值是否为自己的客户端id
如果id token由token接口直接颁发给客户端（授权码模式就是如此），客户端必须根据alg参数值的算法验证签名。客户端必须使用签发方提供的秘钥。
alg值默认为RS256，客户端可以在注册的时候使用id_token_signed_response_alg参数指定配置。
如果jwt的alg头使用了基于mac地址的加密算法，如HS256, HS384,HS512，aud声明中的字节会用作验签。（意思是会把mac地址相关信息写在aud声明上？）
The current time MUST be before the time represented by the exp Claim.

当前时间必须早于exp（token过期时间）。
iat（签发时间）可以用于拒绝过早、或者过于频繁签发的token，可以用于预防重放攻击。可接受时间范围由客户端自行决定。
如果认证请求包含了nonce参数，客户端必须交验认证响应中返回的nonce值是否一致。防止重放攻击。
如果客户端请求了acr声明（Authentication Context Class Reference，认证会话上下文，用于表示当前认证会话），必须交验acr值是否合法。
如果客户端请求了auth_time声明，客户端应该校验认证时间是否已经超出，是否需要重新认证。

access token校验

如果id_token中包含了at_hash声明，需要做下面的校验。at_hash标明了access_token和id_token之间的会话关联关系，做这个校验可以防跨站伪造。

用idtoken的alg头标明的算法加密access_token，比如alg位RS256，则是用HSA-256算法加密。
取hash值左边一般使用base64url加密
id token中的at_hash值必须跟上个步骤得到的值一致

校验规则很多，了解一下即可，绝大部分属于客户端需要做的部分，绝大部分跟安全有关。这一块的实现可以参考Microsoft.Authentication.OpenIdConnect，这是客户端的实现。我们现在看的IdentityServer是认证服务端的实现。

源码

五种授权模式

有下面几种授权模式可以请求token接口

授权码模式：最常用的code换token
混合模式：混合模式是授权码模式+简化模式混合使用的方式，在用授权码code找token接口换通行/身份令牌的逻辑与授权码模式的逻辑是一样的。idsv4中，混合模式没有自己的单独实现，只是把授权码+简化模式的代码同时调用。
客户端密钥模式：一般用于完全信任的内部系统，密钥换取access_token，由于没有用户参与，scope包含open_id是非法的
用户名密码模式：一般用于第三方对接、无界面交互场景。即username+password换token/id_token，password不一定是密码，也可以是验证码或其他的什么东西，这个完全取决于开发自己的实现
设备流模式（略）

注意：简化模式所有的token都是由认证接口（authorize）一次性返回的，不能使用token接口。

校验请求方法

token接口仅允许POST方法，Content-Type必须为application/x-www-form-urlencoded，否则抛出InvalidRequest错误。

public async Task<IEndpointResult> ProcessAsync(HttpContext context)

    {

        _logger.LogTrace("Processing token request.");

        // validate HTTP

        if (!HttpMethods.IsPost(context.Request.Method) || !context.Request.HasFormContentType)

        {

            _logger.LogWarning("Invalid HTTP request for token endpoint");

            return Error(OidcConstants.TokenErrors.InvalidRequest);

        }

        return await ProcessTokenRequestAsync(context);

    }

处理流程

校验客户端
校验请求参数
创建返回值
返回结果

private async Task<IEndpointResult> ProcessTokenRequestAsync(HttpContext context)

{

    _logger.LogDebug("Start token request.");

    // validate client

    var clientResult = await _clientValidator.ValidateAsync(context);

    if (clientResult.Client == null)

    {

        return Error(OidcConstants.TokenErrors.InvalidClient);

    }

    // validate request

    var form = (await context.Request.ReadFormAsync()).AsNameValueCollection();

    _logger.LogTrace("Calling into token request validator: {type}", _requestValidator.GetType().FullName);

    var requestResult = await _requestValidator.ValidateRequestAsync(form, clientResult);

    if (requestResult.IsError)

    {

        await _events.RaiseAsync(new TokenIssuedFailureEvent(requestResult));

        return Error(requestResult.Error, requestResult.ErrorDescription, requestResult.CustomResponse);

    }

    // create response

    _logger.LogTrace("Calling into token request response generator: {type}", _responseGenerator.GetType().FullName);

    var response = await _responseGenerator.ProcessAsync(requestResult);

    await _events.RaiseAsync(new TokenIssuedSuccessEvent(response, requestResult));

    LogTokens(response, requestResult);

    // return result

    _logger.LogDebug("Token request success.");

    return new TokenResult(response);

}

校验客户端

解码客户端秘钥，对应的处理类是BasicAuthenticationSecretParser，客户端id和秘钥用base64url加密方法放在Authorzaition头上。base64url基本是明文的，因为授权码换token是后端进行的，所以安全性没有问题
解码得到客户端id和秘钥之后，跟store对比校验客户端是否存在，秘钥是否一致。

public async Task<ClientSecretValidationResult> ValidateAsync(HttpContext context)

{

    _logger.LogDebug("Start client validation");

    var fail = new ClientSecretValidationResult

    {

        IsError = true

    };

    var parsedSecret = await _parser.ParseAsync(context);

    if (parsedSecret == null)

    {

        await RaiseFailureEventAsync("unknown", "No client id found");

        _logger.LogError("No client identifier found");

        return fail;

    }

    // load client

    var client = await _clients.FindEnabledClientByIdAsync(parsedSecret.Id);

    if (client == null)

    {

        await RaiseFailureEventAsync(parsedSecret.Id, "Unknown client");

        _logger.LogError("No client with id '{clientId}' found. aborting", parsedSecret.Id);

        return fail;

    }

    SecretValidationResult secretValidationResult = null;

    if (!client.RequireClientSecret || client.IsImplicitOnly())

    {

        _logger.LogDebug("Public Client - skipping secret validation success");

    }

    else

    {

        secretValidationResult = await _validator.ValidateAsync(parsedSecret, client.ClientSecrets);

        if (secretValidationResult.Success == false)

        {

            await RaiseFailureEventAsync(client.ClientId, "Invalid client secret");

            _logger.LogError("Client secret validation failed for client: {clientId}.", client.ClientId);

            return fail;

        }

    }

    _logger.LogDebug("Client validation success");

    var success = new ClientSecretValidationResult

    {

        IsError = false,

        Client = client,

        Secret = parsedSecret,

        Confirmation = secretValidationResult?.Confirmation

    };

    await RaiseSuccessEventAsync(client.ClientId, parsedSecret.Type);

    return success;

}

校验请求参数

客户端的PortocalType必须位oidc，否则报错InvalidClient
校验GrantType，必填，长度不能超过100。
GrantType默认支持以下几种类型，还可以自定义GrantType
- authorization_code：授权码换token
- client_credentials：客户端秘钥换token
- password：用户名密码换token
- refresn_token：刷新令牌换token
- urn:ietf:params:oauth:grant-type:device_code：deviceflow，略

public async Task<TokenRequestValidationResult> ValidateRequestAsync(NameValueCollection parameters, ClientSecretValidationResult clientValidationResult)

{

    _logger.LogDebug("Start token request validation");

    _validatedRequest = new ValidatedTokenRequest

    {

        Raw = parameters ?? throw new ArgumentNullException(nameof(parameters)),

        Options = _options

    };

    if (clientValidationResult == null) throw new ArgumentNullException(nameof(clientValidationResult));

    _validatedRequest.SetClient(clientValidationResult.Client, clientValidationResult.Secret, clientValidationResult.Confirmation);

    /////////////////////////////////////////////

    // check client protocol type

    /////////////////////////////////////////////

    if (_validatedRequest.Client.ProtocolType != IdentityServerConstants.ProtocolTypes.OpenIdConnect)

    {

        LogError("Invalid protocol type for client",

            new

            {

                clientId = _validatedRequest.Client.ClientId,

                expectedProtocolType = IdentityServerConstants.ProtocolTypes.OpenIdConnect,

                actualProtocolType = _validatedRequest.Client.ProtocolType

            });

        return Invalid(OidcConstants.TokenErrors.InvalidClient);

    }

    /////////////////////////////////////////////

    // check grant type

    /////////////////////////////////////////////

    var grantType = parameters.Get(OidcConstants.TokenRequest.GrantType);

    if (grantType.IsMissing())

    {

        LogError("Grant type is missing");

        return Invalid(OidcConstants.TokenErrors.UnsupportedGrantType);

    }

    if (grantType.Length > _options.InputLengthRestrictions.GrantType)

    {

        LogError("Grant type is too long");

        return Invalid(OidcConstants.TokenErrors.UnsupportedGrantType);

    }

    _validatedRequest.GrantType = grantType;

    switch (grantType)

    {

        case OidcConstants.GrantTypes.AuthorizationCode:

            return await RunValidationAsync(ValidateAuthorizationCodeRequestAsync, parameters);

        case OidcConstants.GrantTypes.ClientCredentials:

            return await RunValidationAsync(ValidateClientCredentialsRequestAsync, parameters);

        case OidcConstants.GrantTypes.Password:

            return await RunValidationAsync(ValidateResourceOwnerCredentialRequestAsync, parameters);

        case OidcConstants.GrantTypes.RefreshToken:

            return await RunValidationAsync(ValidateRefreshTokenRequestAsync, parameters);

        case OidcConstants.GrantTypes.DeviceCode:

            return await RunValidationAsync(ValidateDeviceCodeRequestAsync, parameters);

        default:

            return await RunValidationAsync(ValidateExtensionGrantRequestAsync, parameters);

    }

}

参数校验 - 授权码模式

客户端AllowedGrantTypes必须包含authorization_code或者hybrid,否则报错UnauthorizedClient。
code必填，code长度不能超过100
客户端传过来的code只是授权码的id，从store中取出来授权码对象，如果不存在返回错误InvalidGrant
从store中移除授权码，此处实现了code只是用一次
如果授权码超出有效时长，返回错误invalidGrant
校验授权码对象的客户端id与当前客户端是否一致
redirect_uri必填，且必须与授权码对象保存的redirect_uri一致，否则返回错误UnauthorizedClient
如果请求中没有任何scope，返回错误invalidRequest
判断用户是否启用，这个判断是由可插拔服务IProfileService的IsActive方法来实现的，开发可以注入自己的实现。如果用户禁用将返回错误InvalidGrant。

private async Task<TokenRequestValidationResult> ValidateAuthorizationCodeRequestAsync(NameValueCollection parameters)

    {

        _logger.LogDebug("Start validation of authorization code token request");

        /////////////////////////////////////////////

        // check if client is authorized for grant type

        /////////////////////////////////////////////

        if (!_validatedRequest.Client.AllowedGrantTypes.ToList().Contains(GrantType.AuthorizationCode) &&

            !_validatedRequest.Client.AllowedGrantTypes.ToList().Contains(GrantType.Hybrid))

        {

            LogError("Client not authorized for code flow");

            return Invalid(OidcConstants.TokenErrors.UnauthorizedClient);

        }

        /////////////////////////////////////////////

        // validate authorization code

        /////////////////////////////////////////////

        var code = parameters.Get(OidcConstants.TokenRequest.Code);

        if (code.IsMissing())

        {

            LogError("Authorization code is missing");

            return Invalid(OidcConstants.TokenErrors.InvalidGrant);

        }

        if (code.Length > _options.InputLengthRestrictions.AuthorizationCode)

        {

            LogError("Authorization code is too long");

            return Invalid(OidcConstants.TokenErrors.InvalidGrant);

        }

        _validatedRequest.AuthorizationCodeHandle = code;

        var authZcode = await _authorizationCodeStore.GetAuthorizationCodeAsync(code);

        if (authZcode == null)

        {

            LogError("Invalid authorization code", new { code });

            return Invalid(OidcConstants.TokenErrors.InvalidGrant);

        }

        await _authorizationCodeStore.RemoveAuthorizationCodeAsync(code);

        if (authZcode.CreationTime.HasExceeded(authZcode.Lifetime, _clock.UtcNow.UtcDateTime))

        {

            LogError("Authorization code expired", new { code });

            return Invalid(OidcConstants.TokenErrors.InvalidGrant);

        }

        /////////////////////////////////////////////

        // populate session id

        /////////////////////////////////////////////

        if (authZcode.SessionId.IsPresent())

        {

            _validatedRequest.SessionId = authZcode.SessionId;

        }

        /////////////////////////////////////////////

        // validate client binding

        /////////////////////////////////////////////

        if (authZcode.ClientId != _validatedRequest.Client.ClientId)

        {

            LogError("Client is trying to use a code from a different client", new { clientId = _validatedRequest.Client.ClientId, codeClient = authZcode.ClientId });

            return Invalid(OidcConstants.TokenErrors.InvalidGrant);

        }

        /////////////////////////////////////////////

        // validate code expiration

        /////////////////////////////////////////////

        if (authZcode.CreationTime.HasExceeded(_validatedRequest.Client.AuthorizationCodeLifetime, _clock.UtcNow.UtcDateTime))

        {

            LogError("Authorization code is expired");

            return Invalid(OidcConstants.TokenErrors.InvalidGrant);

        }

        _validatedRequest.AuthorizationCode = authZcode;

        _validatedRequest.Subject = authZcode.Subject;

        /////////////////////////////////////////////

        // validate redirect_uri

        /////////////////////////////////////////////

        var redirectUri = parameters.Get(OidcConstants.TokenRequest.RedirectUri);

        if (redirectUri.IsMissing())

        {

            LogError("Redirect URI is missing");

            return Invalid(OidcConstants.TokenErrors.UnauthorizedClient);

        }

        if (redirectUri.Equals(_validatedRequest.AuthorizationCode.RedirectUri, StringComparison.Ordinal) == false)

        {

            LogError("Invalid redirect_uri", new { redirectUri, expectedRedirectUri = _validatedRequest.AuthorizationCode.RedirectUri });

            return Invalid(OidcConstants.TokenErrors.UnauthorizedClient);

        }

        /////////////////////////////////////////////

        // validate scopes are present

        /////////////////////////////////////////////

        if (_validatedRequest.AuthorizationCode.RequestedScopes == null ||

            !_validatedRequest.AuthorizationCode.RequestedScopes.Any())

        {

            LogError("Authorization code has no associated scopes");

            return Invalid(OidcConstants.TokenErrors.InvalidRequest);

        }

        /////////////////////////////////////////////

        // validate PKCE parameters

        /////////////////////////////////////////////

        var codeVerifier = parameters.Get(OidcConstants.TokenRequest.CodeVerifier);

        if (_validatedRequest.Client.RequirePkce || _validatedRequest.AuthorizationCode.CodeChallenge.IsPresent())

        {

            _logger.LogDebug("Client required a proof key for code exchange. Starting PKCE validation");

            var proofKeyResult = ValidateAuthorizationCodeWithProofKeyParameters(codeVerifier, _validatedRequest.AuthorizationCode);

            if (proofKeyResult.IsError)

            {

                return proofKeyResult;

            }

            _validatedRequest.CodeVerifier = codeVerifier;

        }

        else

        {

            if (codeVerifier.IsPresent())

            {

                LogError("Unexpected code_verifier: {codeVerifier}. This happens when the client is trying to use PKCE, but it is not enabled. Set RequirePkce to true.", codeVerifier);

                return Invalid(OidcConstants.TokenErrors.InvalidGrant);

            }

        }

        /////////////////////////////////////////////

        // make sure user is enabled

        /////////////////////////////////////////////

        var isActiveCtx = new IsActiveContext(_validatedRequest.AuthorizationCode.Subject, _validatedRequest.Client, IdentityServerConstants.ProfileIsActiveCallers.AuthorizationCodeValidation);

        await _profile.IsActiveAsync(isActiveCtx);

        if (isActiveCtx.IsActive == false)

        {

            LogError("User has been disabled", new { subjectId = _validatedRequest.AuthorizationCode.Subject.GetSubjectId() });

            return Invalid(OidcConstants.TokenErrors.InvalidGrant);

        }

        _logger.LogDebug("Validation of authorization code token request success");

        return Valid();

    }

参数校验 - 客户端秘钥模式

校验Client是否允许使用客户端秘钥认证模式
校验客户端是否允许访问请求的授权范围scope
scope中包含openid的话返回错误invlidScope，因为本模式没有涉及用户信息
cope中包含offline_access则返回错误InvalidScope，本模式不允许使用refresh_token

private async Task<TokenRequestValidationResult> ValidateClientCredentialsRequestAsync(NameValueCollection parameters)

    {

        _logger.LogDebug("Start client credentials token request validation");

        /////////////////////////////////////////////

        // check if client is authorized for grant type

        /////////////////////////////////////////////

        if (!_validatedRequest.Client.AllowedGrantTypes.ToList().Contains(GrantType.ClientCredentials))

        {

            LogError("Client not authorized for client credentials flow, check the AllowedGrantTypes setting", new { clientId = _validatedRequest.Client.ClientId });

            return Invalid(OidcConstants.TokenErrors.UnauthorizedClient);

        }

        /////////////////////////////////////////////

        // check if client is allowed to request scopes

        /////////////////////////////////////////////

        if (!await ValidateRequestedScopesAsync(parameters, ignoreImplicitIdentityScopes: true, ignoreImplicitOfflineAccess: true))

        {

            return Invalid(OidcConstants.TokenErrors.InvalidScope);

        }

        if (_validatedRequest.ValidatedScopes.ContainsOpenIdScopes)

        {

            LogError("Client cannot request OpenID scopes in client credentials flow", new { clientId = _validatedRequest.Client.ClientId });

            return Invalid(OidcConstants.TokenErrors.InvalidScope);

        }

        if (_validatedRequest.ValidatedScopes.ContainsOfflineAccessScope)

        {

            LogError("Client cannot request a refresh token in client credentials flow", new { clientId = _validatedRequest.Client.ClientId });

            return Invalid(OidcConstants.TokenErrors.InvalidScope);

        }

        _logger.LogDebug("{clientId} credentials token request validation success", _validatedRequest.Client.ClientId);

        return Valid();

    }

参数校验 - 用户名密码模式

校验客户端是否允许使用用户名密码模式，校验失败返回UnauthoriedClient错误
校验客户端是否有权访问所请求的所有scope，校验失败返回InvalidScope错误
从请求中获取username和password参数，未提供username返回InvalidGrant错误，未提供password则设置password位空值
username和password长度不能超过100，否则返回InvalidGrant错误
使用IResourceOwnerPasswordValidator校验username和password，此接口需要开发实现后注入，否则会抛出异常
GrantValidationResult的Subject不能为null，因此开发的IResourceOwnerPasswordValidator实现，校验成功后必须给GrantValidationResult赋值
校验用户是否禁用，根据可插拔服务IProfileService的IsAcrtive方法判断，如果禁用返回IvalidGrant错误。

private async Task<TokenRequestValidationResult> ValidateResourceOwnerCredentialRequestAsync(NameValueCollection parameters)

{

    _logger.LogDebug("Start resource owner password token request validation");

    /////////////////////////////////////////////

    // check if client is authorized for grant type

    /////////////////////////////////////////////

    if (!_validatedRequest.Client.AllowedGrantTypes.Contains(GrantType.ResourceOwnerPassword))

    {

        LogError("Client not authorized for resource owner flow, check the AllowedGrantTypes setting", new { client_id = _validatedRequest.Client.ClientId });

        return Invalid(OidcConstants.TokenErrors.UnauthorizedClient);

    }

    /////////////////////////////////////////////

    // check if client is allowed to request scopes

    /////////////////////////////////////////////

    if (!(await ValidateRequestedScopesAsync(parameters)))

    {

        return Invalid(OidcConstants.TokenErrors.InvalidScope);

    }

    /////////////////////////////////////////////

    // check resource owner credentials

    /////////////////////////////////////////////

    var userName = parameters.Get(OidcConstants.TokenRequest.UserName);

    var password = parameters.Get(OidcConstants.TokenRequest.Password);

    if (userName.IsMissing())

    {

        LogError("Username is missing");

        return Invalid(OidcConstants.TokenErrors.InvalidGrant);

    }

    if (password.IsMissing())

    {

        password = "";

    }

    if (userName.Length > _options.InputLengthRestrictions.UserName ||

        password.Length > _options.InputLengthRestrictions.Password)

    {

        LogError("Username or password too long");

        return Invalid(OidcConstants.TokenErrors.InvalidGrant);

    }

    _validatedRequest.UserName = userName;

    /////////////////////////////////////////////

    // authenticate user

    /////////////////////////////////////////////

    var resourceOwnerContext = new ResourceOwnerPasswordValidationContext

    {

        UserName = userName,

        Password = password,

        Request = _validatedRequest

    };

    await _resourceOwnerValidator.ValidateAsync(resourceOwnerContext);

    if (resourceOwnerContext.Result.IsError)

    {

        // protect against bad validator implementations

        resourceOwnerContext.Result.Error = resourceOwnerContext.Result.Error ?? OidcConstants.TokenErrors.InvalidGrant;

        if (resourceOwnerContext.Result.Error == OidcConstants.TokenErrors.UnsupportedGrantType)

        {

            LogError("Resource owner password credential grant type not supported");

            await RaiseFailedResourceOwnerAuthenticationEventAsync(userName, "password grant type not supported", resourceOwnerContext.Request.Client.ClientId);

            return Invalid(OidcConstants.TokenErrors.UnsupportedGrantType, customResponse: resourceOwnerContext.Result.CustomResponse);

        }

        var errorDescription = "invalid_username_or_password";

        if (resourceOwnerContext.Result.ErrorDescription.IsPresent())

        {

            errorDescription = resourceOwnerContext.Result.ErrorDescription;

        }

        LogInformation("User authentication failed: ", errorDescription ?? resourceOwnerContext.Result.Error);

        await RaiseFailedResourceOwnerAuthenticationEventAsync(userName, errorDescription, resourceOwnerContext.Request.Client.ClientId);

        return Invalid(resourceOwnerContext.Result.Error, errorDescription, resourceOwnerContext.Result.CustomResponse);

    }

    if (resourceOwnerContext.Result.Subject == null)

    {

        var error = "User authentication failed: no principal returned";

        LogError(error);

        await RaiseFailedResourceOwnerAuthenticationEventAsync(userName, error, resourceOwnerContext.Request.Client.ClientId);

        return Invalid(OidcConstants.TokenErrors.InvalidGrant);

    }

    /////////////////////////////////////////////

    // make sure user is enabled

    /////////////////////////////////////////////

    var isActiveCtx = new IsActiveContext(resourceOwnerContext.Result.Subject, _validatedRequest.Client, IdentityServerConstants.ProfileIsActiveCallers.ResourceOwnerValidation);

    await _profile.IsActiveAsync(isActiveCtx);

    if (isActiveCtx.IsActive == false)

    {

        LogError("User has been disabled", new { subjectId = resourceOwnerContext.Result.Subject.GetSubjectId() });

        await RaiseFailedResourceOwnerAuthenticationEventAsync(userName, "user is inactive", resourceOwnerContext.Request.Client.ClientId);

        return Invalid(OidcConstants.TokenErrors.InvalidGrant);

    }

    _validatedRequest.UserName = userName;

    _validatedRequest.Subject = resourceOwnerContext.Result.Subject;

    await RaiseSuccessfulResourceOwnerAuthenticationEventAsync(userName, resourceOwnerContext.Result.Subject.GetSubjectId(), resourceOwnerContext.Request.Client.ClientId);

    _logger.LogDebug("Resource owner password token request validation success.");

    return Valid(resourceOwnerContext.Result.CustomResponse);

}

参数校验 - RefreshToken

RefreshToken-刷新令牌。顾名思义，用于刷新通行令牌的凭证。拥有offline_access权限的客户端可以使用刷新令牌。只有授权码、混合流程等由后端参与的授权模式才允许使用刷新令牌。

从请求中获取refresh_token参数值，如果为空则返回InvalidRequest错误
如果刷新令牌长度超过100，返回InvalidGrant错误
判断刷新令牌是否存在且有效
- 是否能从store中查询到刷新令牌对象
- 校验刷新令牌是否过期
- 校验刷新令牌是否属于当前客户端
- 校验客户端是否仍然有offline_access权限
- 校验用户是否被禁用

private async Task<TokenRequestValidationResult> ValidateRefreshTokenRequestAsync(NameValueCollection parameters)

{

    _logger.LogDebug("Start validation of refresh token request");

    var refreshTokenHandle = parameters.Get(OidcConstants.TokenRequest.RefreshToken);

    if (refreshTokenHandle.IsMissing())

    {

        LogError("Refresh token is missing");

        return Invalid(OidcConstants.TokenErrors.InvalidRequest);

    }

    if (refreshTokenHandle.Length > _options.InputLengthRestrictions.RefreshToken)

    {

        LogError("Refresh token too long");

        return Invalid(OidcConstants.TokenErrors.InvalidGrant);

    }

    var result = await _tokenValidator.ValidateRefreshTokenAsync(refreshTokenHandle, _validatedRequest.Client);

    if (result.IsError)

    {

        LogWarning("Refresh token validation failed. aborting");

        return Invalid(OidcConstants.TokenErrors.InvalidGrant);

    }

    _validatedRequest.RefreshToken = result.RefreshToken;

    _validatedRequest.RefreshTokenHandle = refreshTokenHandle;

    _validatedRequest.Subject = result.RefreshToken.Subject;

    _logger.LogDebug("Validation of refresh token request success");

    return Valid();

}

生成响应报文 - 授权码模式

生成accessToken和refreshToken
- 通行令牌由ITokenService接口，默认实现DefaultTokenService的CreateAccessTokenAsync方法生成
- 如果请求了offline_access才生成refresh_token
- 如果code是oidc授权码，生成id_token。DefaultTokenService的CreateIdentityTokenAsync方法生成Token对象，CreateSecurityTokenAsync方法将Token对象加密为jwt。

protected virtual async Task<TokenResponse> ProcessAuthorizationCodeRequestAsync(TokenRequestValidationResult request)

    {

        Logger.LogTrace("Creating response for authorization code request");

        //////////////////////////

        // access token

        /////////////////////////

        (var accessToken, var refreshToken) = await CreateAccessTokenAsync(request.ValidatedRequest);

        var response = new TokenResponse

        {

            AccessToken = accessToken,

            AccessTokenLifetime = request.ValidatedRequest.AccessTokenLifetime,

            Custom = request.CustomResponse,

            Scope = request.ValidatedRequest.AuthorizationCode.RequestedScopes.ToSpaceSeparatedString(),

        };

        //////////////////////////

        // refresh token

        /////////////////////////

        if (refreshToken.IsPresent())

        {

            response.RefreshToken = refreshToken;

        }

        //////////////////////////

        // id token

        /////////////////////////

        if (request.ValidatedRequest.AuthorizationCode.IsOpenId)

        {

            // load the client that belongs to the authorization code

            Client client = null;

            if (request.ValidatedRequest.AuthorizationCode.ClientId != null)

            {

                client = await Clients.FindEnabledClientByIdAsync(request.ValidatedRequest.AuthorizationCode.ClientId);

            }

            if (client == null)

            {

                throw new InvalidOperationException("Client does not exist anymore.");

            }

            var resources = await Resources.FindEnabledResourcesByScopeAsync(request.ValidatedRequest.AuthorizationCode.RequestedScopes);

            var tokenRequest = new TokenCreationRequest

            {

                Subject = request.ValidatedRequest.AuthorizationCode.Subject,

                Resources = resources,

                Nonce = request.ValidatedRequest.AuthorizationCode.Nonce,

                AccessTokenToHash = response.AccessToken,

                StateHash = request.ValidatedRequest.AuthorizationCode.StateHash,

                ValidatedRequest = request.ValidatedRequest

            };

            var idToken = await TokenService.CreateIdentityTokenAsync(tokenRequest);

            var jwt = await TokenService.CreateSecurityTokenAsync(idToken);

            response.IdentityToken = jwt;

        }

        return response;

    }

生成响应报文 - 客户端密钥模式

仅生成accessToken

protected virtual Task<TokenResponse> ProcessClientCredentialsRequestAsync(TokenRequestValidationResult request)

{

    Logger.LogTrace("Creating response for client credentials request");

    return ProcessTokenRequestAsync(request);

}

protected virtual async Task<TokenResponse> ProcessTokenRequestAsync(TokenRequestValidationResult validationResult)

    {

        (var accessToken, var refreshToken) = await CreateAccessTokenAsync(validationResult.ValidatedRequest);

        var response = new TokenResponse

        {

            AccessToken = accessToken,

            AccessTokenLifetime = validationResult.ValidatedRequest.AccessTokenLifetime,

            Custom = validationResult.CustomResponse,

            Scope = validationResult.ValidatedRequest.Scopes.ToSpaceSeparatedString()

        };

        if (refreshToken.IsPresent())

        {

            response.RefreshToken = refreshToken;

        }

        return response;

    }

生成响应报文 - 用户名密码模式

生成accessToken
如果申请了offline_access且有权限，同时返回refresh_token
不会返回id_token，我理解的是授权码等模式是有限授权，需要code换id_token，才能拿到用户id以及其他的基本信息。而密码模式是完全信任授权，账号密码都给你了，还整id_token干嘛，你要啥信息，自己实现IResourceOwnerPasswordValidator，自己去库里取就完事了，还要啥自行车。

protected virtual Task<TokenResponse> ProcessPasswordRequestAsync(TokenRequestValidationResult request)

    {

        Logger.LogTrace("Creating response for password request");

        return ProcessTokenRequestAsync(request);

    }

生成响应报文 - 刷新令牌

从请求中取出旧通行令牌
判断客户端配置UpdateAccessTokenClaimsOnRefresh-是否在刷新令牌的时候更新通行令牌的claims，默认false。如果为true，则创建新的token对象，否则使用旧的token，只是刷新token的创建时间和有效时间。
判断客户端配置RefreshTokenUsage - 刷新令牌用法，0：ReUse可重复使用 1：OnTimeOnly一次性，默认1。如果是一次性的话，从store中删除旧的刷新令牌，创建新的刷新令牌。
判断客户端配置RefreshTokenExpiration - 刷新令牌过期类型，0：Sliding，1：Absolute，默认1。如果是0，需要重新计算相对时间。
如果刷新令牌请求包含了任意身份资源，创建新的身份令牌。

protected virtual async Task<TokenResponse> ProcessRefreshTokenRequestAsync(TokenRequestValidationResult request)

    {

        Logger.LogTrace("Creating response for refresh token request");

        var oldAccessToken = request.ValidatedRequest.RefreshToken.AccessToken;

        string accessTokenString;

        if (request.ValidatedRequest.Client.UpdateAccessTokenClaimsOnRefresh)

        {

            var subject = request.ValidatedRequest.RefreshToken.Subject;

            var creationRequest = new TokenCreationRequest

            {

                Subject = subject,

                ValidatedRequest = request.ValidatedRequest,

                Resources = await Resources.FindEnabledResourcesByScopeAsync(oldAccessToken.Scopes)

            };

            var newAccessToken = await TokenService.CreateAccessTokenAsync(creationRequest);

            accessTokenString = await TokenService.CreateSecurityTokenAsync(newAccessToken);

        }

        else

        {

            oldAccessToken.CreationTime = Clock.UtcNow.UtcDateTime;

            oldAccessToken.Lifetime = request.ValidatedRequest.AccessTokenLifetime;

            accessTokenString = await TokenService.CreateSecurityTokenAsync(oldAccessToken);

        }

        var handle = await RefreshTokenService.UpdateRefreshTokenAsync(request.ValidatedRequest.RefreshTokenHandle, request.ValidatedRequest.RefreshToken, request.ValidatedRequest.Client);

        return new TokenResponse

        {

            IdentityToken = await CreateIdTokenFromRefreshTokenRequestAsync(request.ValidatedRequest, accessTokenString),

            AccessToken = accessTokenString,

            AccessTokenLifetime = request.ValidatedRequest.AccessTokenLifetime,

            RefreshToken = handle,

            Custom = request.CustomResponse,

            Scope = request.ValidatedRequest.RefreshToken.Scopes.ToSpaceSeparatedString()

        };

    }

令牌

IdentityServer4源码解析_4_令牌发放接口

目录

协议