我建议你看看下面的链接。
https://stormpath.com/blog/token-authentication-asp-net-core
他们将 JWT 令牌存储在仅限 http 的 cookie 中以防止 XSS 攻击。
然后他们通过在 Startup.cs 中添加以下代码来验证 cookie 中的 JWT 令牌：
app.UseCookieAuthentication(new CookieAuthenticationOptions
{
AutomaticAuthenticate = true,
AutomaticChallenge = true,
AuthenticationScheme = "Cookie",
CookieName = "access_token",
TicketDataFormat = new CustomJwtDataFormat(
SecurityAlgorithms.HmacSha256,
tokenValidationParameters)
});
CustomJwtDataFormat() 是这里定义的自定义格式：
public class CustomJwtDataFormat : ISecureDataFormat<AuthenticationTicket>
{
private readonly string algorithm;
private readonly TokenValidationParameters validationParameters;
public CustomJwtDataFormat(string algorithm, TokenValidationParameters validationParameters)
{
this.algorithm = algorithm;
this.validationParameters = validationParameters;
}
public AuthenticationTicket Unprotect(string protectedText)
=> Unprotect(protectedText, null);
public AuthenticationTicket Unprotect(string protectedText, string purpose)
{
var handler = new JwtSecurityTokenHandler();
ClaimsPrincipal principal = null;
SecurityToken validToken = null;
try
{
principal = handler.ValidateToken(protectedText, this.validationParameters, out validToken);
var validJwt = validToken as JwtSecurityToken;
if (validJwt == null)
{
throw new ArgumentException("Invalid JWT");
}
if (!validJwt.Header.Alg.Equals(algorithm, StringComparison.Ordinal))
{
throw new ArgumentException($"Algorithm must be '{algorithm}'");
}
// Additional custom validation of JWT claims here (if any)
}
catch (SecurityTokenValidationException)
{
return null;
}
catch (ArgumentException)
{
return null;
}
// Validation passed. Return a valid AuthenticationTicket:
return new AuthenticationTicket(principal, new AuthenticationProperties(), "Cookie");
}
// This ISecureDataFormat implementation is decode-only
public string Protect(AuthenticationTicket data)
{
throw new NotImplementedException();
}
public string Protect(AuthenticationTicket data, string purpose)
{
throw new NotImplementedException();
}
}
另一种解决方案是编写一些自定义中间件来拦截每个请求，查看它是否有 cookie，从 cookie 中提取 JWT 并在到达控制器的 Authorize 过滤器之前动态添加 Authorization 标头。下面是一些适用于 OAuth 令牌的代码，以了解这个想法：
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Logging;
namespace MiddlewareSample
{
public class JWTInHeaderMiddleware
{
private readonly RequestDelegate _next;
public JWTInHeaderMiddleware(RequestDelegate next)
{
_next = next;
}
public async Task Invoke(HttpContext context)
{
var authenticationCookieName = "access_token";
var cookie = context.Request.Cookies[authenticationCookieName];
if (cookie != null)
{
var token = JsonConvert.DeserializeObject<AccessToken>(cookie);
context.Request.Headers.Append("Authorization", "Bearer " + token.access_token);
}
await _next.Invoke(context);
}
}
}
...其中 AccessToken 是以下类：
public class AccessToken
{
public string token_type { get; set; }
public string access_token { get; set; }
public string expires_in { get; set; }
}
希望这会有所帮助。
注意：同样重要的是要注意，这种处理方式（仅在 http cookie 中的令牌）将有助于防止 XSS 攻击，但不能抵抗跨站请求伪造 (CSRF) 攻击，因此您还必须使用反-伪造令牌或设置自定义标头以防止这些。
此外，如果您不进行任何内容清理，攻击者仍然可以运行 XSS 脚本来代表用户发出请求，即使启用了仅 http cookie 和 CRSF 保护。但是，攻击者将无法窃取包含令牌的仅 http cookie，攻击者也无法从第三方网站发出请求。
因此，您仍应对用户生成的内容（例如 cmets 等）执行严格的清理...
编辑：在博客文章链接的 cmets 中写了代码，几天前在问了这个问题后，OP 自己编写了代码。
对于那些对另一种“cookie 中的令牌”方法感兴趣以减少 XSS 暴露的人，他们可以使用 oAuth 中间件，例如 ASP.NET Core 中的 OpenId Connect Server。
在被调用以将令牌发回 (ApplyTokenResponse()) 到客户端的令牌提供程序的方法中，您可以序列化令牌并将其存储到仅限 http 的 cookie 中：
using System.Security.Claims;
using System.Threading.Tasks;
using AspNet.Security.OpenIdConnect.Extensions;
using AspNet.Security.OpenIdConnect.Server;
using Newtonsoft.Json;
namespace Shared.Providers
{
public class AuthenticationProvider : OpenIdConnectServerProvider
{
private readonly IApplicationService _applicationservice;
private readonly IUserService _userService;
public AuthenticationProvider(IUserService userService,
IApplicationService applicationservice)
{
_applicationservice = applicationservice;
_userService = userService;
}
public override Task ValidateTokenRequest(ValidateTokenRequestContext context)
{
if (string.IsNullOrEmpty(context.ClientId))
{
context.Reject(
error: OpenIdConnectConstants.Errors.InvalidRequest,
description: "Missing credentials: ensure that your credentials were correctly " +
"flowed in the request body or in the authorization header");
return Task.FromResult(0);
}
#region Validate Client
var application = _applicationservice.GetByClientId(context.ClientId);
if (applicationResult == null)
{
context.Reject(
error: OpenIdConnectConstants.Errors.InvalidClient,
description: "Application not found in the database: ensure that your client_id is correct");
return Task.FromResult(0);
}
else
{
var application = applicationResult.Data;
if (application.ApplicationType == (int)ApplicationTypes.JavaScript)
{
// Note: the context is marked as skipped instead of validated because the client
// is not trusted (JavaScript applications cannot keep their credentials secret).
context.Skip();
}
else
{
context.Reject(
error: OpenIdConnectConstants.Errors.InvalidClient,
description: "Authorization server only handles Javascript application.");
return Task.FromResult(0);
}
}
#endregion Validate Client
return Task.FromResult(0);
}
public override async Task HandleTokenRequest(HandleTokenRequestContext context)
{
if (context.Request.IsPasswordGrantType())
{
var username = context.Request.Username.ToLowerInvariant();
var user = await _userService.GetUserLoginDtoAsync(
// filter
u => u.UserName == username
);
if (user == null)
{
context.Reject(
error: OpenIdConnectConstants.Errors.InvalidGrant,
description: "Invalid username or password.");
return;
}
var password = context.Request.Password;
var passWordCheckResult = await _userService.CheckUserPasswordAsync(user, context.Request.Password);
if (!passWordCheckResult)
{
context.Reject(
error: OpenIdConnectConstants.Errors.InvalidGrant,
description: "Invalid username or password.");
return;
}
var roles = await _userService.GetUserRolesAsync(user);
if (!roles.Any())
{
context.Reject(
error: OpenIdConnectConstants.Errors.InvalidRequest,
description: "Invalid user configuration.");
return;
}
// add the claims
var identity = new ClaimsIdentity(context.Options.AuthenticationScheme);
identity.AddClaim(ClaimTypes.NameIdentifier, user.Id, OpenIdConnectConstants.Destinations.AccessToken, OpenIdConnectConstants.Destinations.IdentityToken);
identity.AddClaim(ClaimTypes.Name, user.UserName, OpenIdConnectConstants.Destinations.AccessToken, OpenIdConnectConstants.Destinations.IdentityToken);
// add the user's roles as claims
foreach (var role in roles)
{
identity.AddClaim(ClaimTypes.Role, role, OpenIdConnectConstants.Destinations.AccessToken, OpenIdConnectConstants.Destinations.IdentityToken);
}
context.Validate(new ClaimsPrincipal(identity));
}
else
{
context.Reject(
error: OpenIdConnectConstants.Errors.InvalidGrant,
description: "Invalid grant type.");
return;
}
return;
}
public override Task ApplyTokenResponse(ApplyTokenResponseContext context)
{
var token = context.Response.Root;
var stringified = JsonConvert.SerializeObject(token);
// the token will be stored in a cookie on the client
context.HttpContext.Response.Cookies.Append(
"exampleToken",
stringified,
new Microsoft.AspNetCore.Http.CookieOptions()
{
Path = "/",
HttpOnly = true, // to prevent XSS
Secure = false, // set to true in production
Expires = // your token life time
}
);
return base.ApplyTokenResponse(context);
}
}
}
然后您需要确保每个请求都附加了 cookie。您还必须编写一些中间件来拦截cookie并将其设置为header：
public class AuthorizationHeader
{
private readonly RequestDelegate _next;
public AuthorizationHeader(RequestDelegate next)
{
_next = next;
}
public async Task Invoke(HttpContext context)
{
var authenticationCookieName = "exampleToken";
var cookie = context.Request.Cookies[authenticationCookieName];
if (cookie != null)
{
if (!context.Request.Path.ToString().ToLower().Contains("/account/logout"))
{
if (!string.IsNullOrEmpty(cookie))
{
var token = JsonConvert.DeserializeObject<AccessToken>(cookie);
if (token != null)
{
var headerValue = "Bearer " + token.access_token;
if (context.Request.Headers.ContainsKey("Authorization"))
{
context.Request.Headers["Authorization"] = headerValue;
}else
{
context.Request.Headers.Append("Authorization", headerValue);
}
}
}
await _next.Invoke(context);
}
else
{
// this is a logout request, clear the cookie by making it expire now
context.Response.Cookies.Append(authenticationCookieName,
"",
new Microsoft.AspNetCore.Http.CookieOptions()
{
Path = "/",
HttpOnly = true,
Secure = false,
Expires = DateTime.UtcNow.AddHours(-1)
});
context.Response.Redirect("/");
return;
}
}
else
{
await _next.Invoke(context);
}
}
}
在startup.cs的Configure()中：
// use the AuthorizationHeader middleware
app.UseMiddleware<AuthorizationHeader>();
// Add a new middleware validating access tokens.
app.UseOAuthValidation();
然后就可以正常使用Authorize属性了。
[Authorize(Roles = "Administrator,User")]
此解决方案适用于 api 和 mvc 应用程序。但是对于 ajax 和 fetch 请求，您必须编写一些不会将用户重定向到登录页面而是返回 401 的自定义中间件：
public class RedirectHandler
{
private readonly RequestDelegate _next;
public RedirectHandler(RequestDelegate next)
{
_next = next;
}
public bool IsAjaxRequest(HttpContext context)
{
return context.Request.Headers["X-Requested-With"] == "XMLHttpRequest";
}
public bool IsFetchRequest(HttpContext context)
{
return context.Request.Headers["X-Requested-With"] == "Fetch";
}
public async Task Invoke(HttpContext context)
{
await _next.Invoke(context);
var ajax = IsAjaxRequest(context);
var fetch = IsFetchRequest(context);
if (context.Response.StatusCode == 302 && (ajax || fetch))
{
context.Response.Clear();
context.Response.StatusCode = (int)HttpStatusCode.Unauthorized;
await context.Response.WriteAsync("Unauthorized");
return;
}
}
}