protected override async Task <AuthenticationTicket> CreateTicketAsync(ClaimsIdentity identity, AuthenticationProperties properties, OAuthTokenResponse tokens)
{
var address = QueryHelpers.AddQueryString(Options.UserInformationEndpoint, new Dictionary <string, string>
{
["access_token"] = tokens.AccessToken,
["openid"] = tokens.Response.GetRootString("openid")
});
var response = await Backchannel.GetAsync(address);
if (!response.IsSuccessStatusCode)
{
Logger.LogError("An error occurred while retrieving the user profile: the remote server " +
"returned a {Status} response with the following payload: {Headers} {Body}.",
/* Status: */ response.StatusCode,
/* Headers: */ response.Headers.ToString(),
/* Body: */ await response.Content.ReadAsStringAsync());
throw new HttpRequestException("An error occurred while retrieving user information.");
}
var payload = JsonDocument.Parse(await response.Content.ReadAsStringAsync());
if (!string.IsNullOrEmpty(payload.GetRootString("errcode")))
{
Logger.LogError("An error occurred while retrieving the user profile: the remote server " +
"returned a {Status} response with the following payload: {Headers} {Body}.",
/* Status: */ response.StatusCode,
/* Headers: */ response.Headers.ToString(),
/* Body: */ await response.Content.ReadAsStringAsync());
throw new HttpRequestException("An error occurred while retrieving user information.");
}
var context = new OAuthCreatingTicketContext(new ClaimsPrincipal(identity), properties, Context, Scheme, Options, Backchannel, tokens, payload.RootElement);
context.RunClaimActions();
await Events.CreatingTicket(context);
// TODO: 此处通过唯一的 CorrelationId, 将 properties生成的State缓存删除
var state = Request.Query["state"];
var stateCacheKey = WeChatOfficialStateCacheItem.CalculateCacheKey(state.ToString().ToMd5(), null);
await Cache.RemoveAsync(stateCacheKey, token : Context.RequestAborted);
return(new AuthenticationTicket(context.Principal, context.Properties, Scheme.Name));
}
protected override async Task HandleChallengeAsync(AuthenticationProperties properties)
{
await base.HandleChallengeAsync(properties);
// TODO: 此处已经生成唯一的 CorrelationId, 可以借此将 properties生成State之后再进行缓存
// 注: 默认的State对于微信来说太长(微信只支持128位长度的State),因此巧妙的利用CorrelationId的MD5值来替代State
// MD5转换防止直接通过CorrelationId干些别的事情...
var state = properties.Items[".xsrf"];
var stateToken = Options.StateDataFormat.Protect(properties);
var stateCacheKey = WeChatOfficialStateCacheItem.CalculateCacheKey(state.ToMd5(), null);
await Cache
.SetAsync(
stateCacheKey,
new WeChatOfficialStateCacheItem(stateToken),
new DistributedCacheEntryOptions
{
AbsoluteExpiration = Clock.UtcNow.AddMinutes(2) // TODO: 设定2分钟过期?
},
token : Context.RequestAborted);
}
protected override async Task <HandleRequestResult> HandleRemoteAuthenticateAsync()
{
var query = Request.Query;
// TODO: 此处借用唯一的 CorrelationId, 将 properties生成的State缓存取出,进行解密
var state = query["state"];
var stateCacheKey = WeChatOfficialStateCacheItem.CalculateCacheKey(state.ToString().ToMd5(), null);
var stateCacheItem = await Cache.GetAsync(stateCacheKey, token : Context.RequestAborted);
var properties = Options.StateDataFormat.Unprotect(stateCacheItem.State);
if (properties == null)
{
return(HandleRequestResult.Fail("The oauth state was missing or invalid."));
}
// OAuth2 10.12 CSRF
if (!ValidateCorrelationId(properties))
{
return(HandleRequestResult.Fail("Correlation failed.", properties));
}
var error = query["error"];
if (!StringValues.IsNullOrEmpty(error))
{
// Note: access_denied errors are special protocol errors indicating the user didn't
// approve the authorization demand requested by the remote authorization server.
// Since it's a frequent scenario (that is not caused by incorrect configuration),
// denied errors are handled differently using HandleAccessDeniedErrorAsync().
// Visit https://tools.ietf.org/html/rfc6749#section-4.1.2.1 for more information.
var errorDescription = query["error_description"];
var errorUri = query["error_uri"];
if (StringValues.Equals(error, "access_denied"))
{
var result = await HandleAccessDeniedErrorAsync(properties);
if (!result.None)
{
return(result);
}
var deniedEx = new Exception("Access was denied by the resource owner or by the remote server.");
deniedEx.Data["error"] = error.ToString();
deniedEx.Data["error_description"] = errorDescription.ToString();
deniedEx.Data["error_uri"] = errorUri.ToString();
return(HandleRequestResult.Fail(deniedEx, properties));
}
var failureMessage = new StringBuilder();
failureMessage.Append(error);
if (!StringValues.IsNullOrEmpty(errorDescription))
{
failureMessage.Append(";Description=").Append(errorDescription);
}
if (!StringValues.IsNullOrEmpty(errorUri))
{
failureMessage.Append(";Uri=").Append(errorUri);
}
var ex = new Exception(failureMessage.ToString());
ex.Data["error"] = error.ToString();
ex.Data["error_description"] = errorDescription.ToString();
ex.Data["error_uri"] = errorUri.ToString();
return(HandleRequestResult.Fail(ex, properties));
}
var code = query["code"];
if (StringValues.IsNullOrEmpty(code))
{
return(HandleRequestResult.Fail("Code was not found.", properties));
}
var codeExchangeContext = new OAuthCodeExchangeContext(properties, code, BuildRedirectUri(Options.CallbackPath));
using var tokens = await ExchangeCodeAsync(codeExchangeContext);
if (tokens.Error != null)
{
return(HandleRequestResult.Fail(tokens.Error, properties));
}
if (string.IsNullOrEmpty(tokens.AccessToken))
{
return(HandleRequestResult.Fail("Failed to retrieve access token.", properties));
}
var identity = new ClaimsIdentity(ClaimsIssuer);
if (Options.SaveTokens)
{
var authTokens = new List <AuthenticationToken>();
authTokens.Add(new AuthenticationToken {
Name = "access_token", Value = tokens.AccessToken
});
if (!string.IsNullOrEmpty(tokens.RefreshToken))
{
authTokens.Add(new AuthenticationToken {
Name = "refresh_token", Value = tokens.RefreshToken
});
}
if (!string.IsNullOrEmpty(tokens.TokenType))
{
authTokens.Add(new AuthenticationToken {
Name = "token_type", Value = tokens.TokenType
});
}
if (!string.IsNullOrEmpty(tokens.ExpiresIn))
{
int value;
if (int.TryParse(tokens.ExpiresIn, NumberStyles.Integer, CultureInfo.InvariantCulture, out value))
{
// https://www.w3.org/TR/xmlschema-2/#dateTime
// https://msdn.microsoft.com/en-us/library/az4se3k1(v=vs.110).aspx
var expiresAt = Clock.UtcNow + TimeSpan.FromSeconds(value);
authTokens.Add(new AuthenticationToken
{
Name = "expires_at",
Value = expiresAt.ToString("o", CultureInfo.InvariantCulture)
});
}
}
properties.StoreTokens(authTokens);
}
var ticket = await CreateTicketAsync(identity, properties, tokens);
if (ticket != null)
{
return(HandleRequestResult.Success(ticket));
}
else
{
return(HandleRequestResult.Fail("Failed to retrieve user information from remote server.", properties));
}
}