Web API中基于令牌的身份验证,没有任何用户界面

Question

我正在ASP.Net Web API中开发REST API.我的API只能通过非基于浏览器的客户端访问.我需要为我的API实现安全性,所以我决定使用基于令牌的身份验证.我对基于令牌的身份验证有一个公平的理解,并阅读了一些教程,但他们都有一些用于登录的用户界面.我不需要任何用于登录的UI,因为登录详细信息将由客户端通过HTTP POST传递,HTTP POST将从我们的数据库授权.如何在API中实现基于令牌的身份验证？请注意 - 我的API将以高频率访问,因此我还必须注意性能.如果我能更好地解释,请告诉我.

Answer 1

我认为MVC和Web Api之间存在一些混淆.简而言之,对于MVC,您可以使用登录表单并使用cookie创建会话.对于Web Api,没有会话.这就是你想要使用令牌的原因.

您不需要登录表单.Token端点就是您所需要的.与Win描述的一样,您将把凭据发送到处理它的令牌端点.

这里有一些客户端C#代码来获取令牌:

    //using System;
    //using System.Collections.Generic;
    //using System.Net;
    //using System.Net.Http;
    //string token = GetToken("https://localhost:<port>/", userName, password);

    static string GetToken(string url, string userName, string password) {
        var pairs = new List<KeyValuePair<string, string>>
                    {
                        new KeyValuePair<string, string>( "grant_type", "password" ), 
                        new KeyValuePair<string, string>( "username", userName ), 
                        new KeyValuePair<string, string> ( "Password", password )
                    };
        var content = new FormUrlEncodedContent(pairs);
        ServicePointManager.ServerCertificateValidationCallback += (sender, cert, chain, sslPolicyErrors) => true;
        using (var client = new HttpClient()) {
            var response = client.PostAsync(url + "Token", content).Result;
            return response.Content.ReadAsStringAsync().Result;
        }
    }

要使用令牌,请将其添加到请求的标头中:

    //using System;
    //using System.Collections.Generic;
    //using System.Net;
    //using System.Net.Http;
    //var result = CallApi("https://localhost:<port>/something", token);

    static string CallApi(string url, string token) {
        ServicePointManager.ServerCertificateValidationCallback += (sender, cert, chain, sslPolicyErrors) => true;
        using (var client = new HttpClient()) {
            if (!string.IsNullOrWhiteSpace(token)) {
                var t = JsonConvert.DeserializeObject<Token>(token);

                client.DefaultRequestHeaders.Clear();
                client.DefaultRequestHeaders.Add("Authorization", "Bearer " + t.access_token);
            }
            var response = client.GetAsync(url).Result;
            return response.Content.ReadAsStringAsync().Result;
        }
    }

令牌是:

//using Newtonsoft.Json;

class Token
{
    public string access_token { get; set; }
    public string token_type { get; set; }
    public int expires_in { get; set; }
    public string userName { get; set; }
    [JsonProperty(".issued")]
    public string issued { get; set; }
    [JsonProperty(".expires")]
    public string expires { get; set; }
}

现在为服务器端:

在Startup.Auth.cs中

        var oAuthOptions = new OAuthAuthorizationServerOptions
        {
            TokenEndpointPath = new PathString("/Token"),
            Provider = new ApplicationOAuthProvider("self"),
            AccessTokenExpireTimeSpan = TimeSpan.FromDays(14),
            // https
            AllowInsecureHttp = false
        };
        // Enable the application to use bearer tokens to authenticate users
        app.UseOAuthBearerTokens(oAuthOptions);

在ApplicationOAuthProvider.cs中,实际授予或拒绝访问的代码:

//using Microsoft.AspNet.Identity.Owin;
//using Microsoft.Owin.Security;
//using Microsoft.Owin.Security.OAuth;
//using System;
//using System.Collections.Generic;
//using System.Security.Claims;
//using System.Threading.Tasks;

public class ApplicationOAuthProvider : OAuthAuthorizationServerProvider
{
    private readonly string _publicClientId;

    public ApplicationOAuthProvider(string publicClientId)
    {
        if (publicClientId == null)
            throw new ArgumentNullException("publicClientId");

        _publicClientId = publicClientId;
    }

    public override async Task GrantResourceOwnerCredentials(OAuthGrantResourceOwnerCredentialsContext context)
    {
        var userManager = context.OwinContext.GetUserManager<ApplicationUserManager>();

        var user = await userManager.FindAsync(context.UserName, context.Password);
        if (user == null)
        {
            context.SetError("invalid_grant", "The user name or password is incorrect.");
            return;
        }

        ClaimsIdentity oAuthIdentity = await user.GenerateUserIdentityAsync(userManager);
        var propertyDictionary = new Dictionary<string, string> { { "userName", user.UserName } };
        var properties = new AuthenticationProperties(propertyDictionary);

        AuthenticationTicket ticket = new AuthenticationTicket(oAuthIdentity, properties);
        // Token is validated.
        context.Validated(ticket);
    }

    public override Task TokenEndpoint(OAuthTokenEndpointContext context)
    {
        foreach (KeyValuePair<string, string> property in context.Properties.Dictionary)
        {
            context.AdditionalResponseParameters.Add(property.Key, property.Value);
        }
        return Task.FromResult<object>(null);
    }

    public override Task ValidateClientAuthentication(OAuthValidateClientAuthenticationContext context)
    {
        // Resource owner password credentials does not provide a client ID.
        if (context.ClientId == null)
            context.Validated();

        return Task.FromResult<object>(null);
    }

    public override Task ValidateClientRedirectUri(OAuthValidateClientRedirectUriContext context)
    {
        if (context.ClientId == _publicClientId)
        {
            var expectedRootUri = new Uri(context.Request.Uri, "/");

            if (expectedRootUri.AbsoluteUri == context.RedirectUri)
                context.Validated();
        }
        return Task.FromResult<object>(null);
    }

}

如您所见,检索令牌不涉及控制器.实际上,如果只需要Web Api,则可以删除所有MVC引用.我简化了服务器端代码,使其更具可读性.您可以添加代码来升级安全性.

确保仅使用SSL.实现RequireHttpsAttribute以强制执行此操作.

您可以使用Authorize/AllowAnonymous属性来保护Web Api.此外,您可以添加过滤器(如RequireHttpsAttribute)以使您的Web Api更安全.我希望这有帮助.

Answer 2

ASP.Net Web API已经具有Authorization Server内置功能.当您使用Web API模板创建新的ASP.Net Web应用程序时,可以在Startup.cs中看到它.

OAuthOptions = new OAuthAuthorizationServerOptions
{
    TokenEndpointPath = new PathString("/Token"),
    Provider = new ApplicationOAuthProvider(PublicClientId),
    AuthorizeEndpointPath = new PathString("/api/Account/ExternalLogin"),
    AccessTokenExpireTimeSpan = TimeSpan.FromDays(14),
    // In production mode set AllowInsecureHttp = false
    AllowInsecureHttp = true
};

您所要做的就是在查询字符串中发布URL编码的用户名和密码.

/Token/userName=johndoe%40example.com&password=1234&grant_type=password

如果您想了解更多细节,可以通过Deborah Kurata观看 用户注册和登录 - Angular Front to Back with Web API.