Question

使用Web Api 2.2，我有一个自定义IAuthenticationFilter，用于通过自定义方案验证客户端请求。

基本上，当客户端未经过身份验证并想要访问受保护资源时，他会在请求旁边发送Authorization标头：Authorization: MyCustomScheme XXXXXXX。然后，过滤器验证凭据，对用户进行身份验证并生成无状态身份验证令牌以进一步访问（类似于JWT）。

我想将生成的身份验证令牌存储在cookie中。当存在于传入请求中时，cookie将在单独的过滤器中进行本地验证（此处未显示）。

我的问题是，如果我尝试像这样设置cookie：

Task IAuthenticationFilter.AuthenticateAsync(HttpAuthenticationContext context, CancellationToken cancellationToken)
{
    if (context.Request.Headers.Authorization != null &&
        string.Equals(context.Request.Headers.Authorization.Scheme, "MyCustomScheme", StringComparison.OrdinalIgnoreCase))
    {
        // This works
        CustomPrincipal principal = this.ValidateCredentials(context.Request.Headers.Authorization.Parameter);
        context.Principal = principal;

        // This doesn't work: context.ActionContext.Response is null
        var cookie = new CookieHeaderValue("MySessionCookie", principal.AuthenticationToken) { Path = "/", HttpOnly = true };
        context.ActionContext.Response.Headers.AddCookies(new CookieHeaderValue[] { cookie });
    }
    return Task.FromResult(0);
}

然后它失败，因为context.ActionContext.Response为空。如何在AuthenticateAsync内的响应中添加Cookie？

参见相关内容：Setting Cookie values in HttpAuthenticationContext for IAuthenticationFilter （你可以在评论中看到人们遇到同样的问题）。

Answer 1

除了IActionFilter之外，我还通过实施IAuthenticationFilter来使用过滤器。此方法有效，因为您可以在同一位置访问请求，响应和用户标识。这是我的实施：

async Task<HttpResponseMessage> IActionFilter.ExecuteActionFilterAsync(HttpActionContext actionContext, CancellationToken cancellationToken, Func<Task<HttpResponseMessage>> continuation)
{
    // Process the request pipeline and get the response (this causes the action to be executed)
    HttpResponseMessage response = await continuation();

    // If the user is authenticated and the token is not present in the request cookies, then it needs to be set
    CustomPrincipal principal = actionContext.ControllerContext.RequestContext.Principal as CustomPrincipal;
    if (principal != null && !actionContext.Request.Headers.GetCookies("MySessionCookie").Any())
    {
        // Set the cookie in the response
        var cookie = new CookieHeaderValue("MySessionCookie", principal.AuthenticationToken) { Path = "/", HttpOnly = true };
        response.Headers.AddCookies(new CookieHeaderValue[] { cookie });
    }

    return response;
}

我觉得这个方法非常不实用（混合接口），你绝对应该可以访问IAuthenticationFilter.AuthenticateAsync中的响应（通过例如异步延续回调，或者能够访问动作结果{{1在上下文中，就像在同一个接口的IHttpActionResult方法中一样）。

Answer 2

我的要求是添加标题，但应该很容易适应添加Cookie。

我对此采取了不同的方法。我把我要添加的标题添加到context.Request.Properties中。然后在ChallengeAsync中（无论是否为每个请求调用），通过IHttpActionResult我检查是否存在属性，如果存在则将其添加到标题中。像这样：

protected class AddRenewOnAauthorizedResult : IHttpActionResult {

    public const string RenewalPropertyKey = "ETicket.RenewalKey";

    public AddRenewOnAauthorizedResult(HttpRequestMessage request, IHttpActionResult innerResult) {
        this.Request = request;
        this.InnerResult = innerResult;
    }

    public HttpRequestMessage Request { get; set; }
    public IHttpActionResult InnerResult { get; set; }

    public async Task<HttpResponseMessage> ExecuteAsync(CancellationToken cancellationToken) {

        HttpResponseMessage response = await this.InnerResult.ExecuteAsync(cancellationToken);

        if (Request.Properties.ContainsKey(RenewalPropertyKey)) Request.response.Headers.Add("X-ETicket-Renew", Request.Properties(RenewalPropertyKey));

        Return response;

}

}

然后在ChallengeAsync：

public Threading.Tasks.Task ChallengeAsync(HttpAuthenticationChallengeContext context, Threading.CancellationToken cancellationToken)
{

    context.Result = new AddRenewOnAauthorizedResult(context.Request, context.Result);
    return Task.FromResult(0);

}

Answer 3

您可能需要实施IRequiresSessionState才能使Cookie保持不变？

请参阅：http://www.strathweb.com/2012/11/adding-session-support-to-asp-net-web-api/

从Web Api 2 IAuthenticationFilter AuthenticateAsync方法设置cookie

3 个答案: