SAML token 大小和 REST

Question

我们正在为基于 REST 的服务实现 STS(基于声明的身份验证)。我们决定创建 REST 服务(使用 JSON)的众多原因之一是线路占用空间小。使用 STS，只有几个声明 SAML 大小的 SAML token 变成了几个 K 字节。对于我们不返回对象列表的大多数 REST 调用，响应大小低 100 字节，对于这些调用，此 token 似乎开销太大。你在你的项目中如何处理这个问题？

Answer 1

... 或 JWT(JSon 网络 token )。 ACS 也支持这些。
查看这篇文章:JSON Web Token Handler for the Microsoft .NET Framework 4.5
下面是这个库的使用示例，它使用基于 HMAC SHA256 的对称 key 签名的 JWT 和 .Net 4.5。

string jwtIssuer = "MyIssuer";
string jwtAudience = "MyAudience";

// Generate symmetric key for HMAC-SHA256 signature
RNGCryptoServiceProvider cryptoProvider = new RNGCryptoServiceProvider();
byte[] keyForHmacSha256 = new byte[64];
cryptoProvider.GetNonZeroBytes(keyForHmacSha256);

///////////////////////////////////////////////////////////////////
// Create signing credentials for the signed JWT.
// This object is used to cryptographically sign the JWT by the issuer.
SigningCredentials sc = new SigningCredentials(
                                new InMemorySymmetricSecurityKey(keyForHmacSha256),
                                "http://www.w3.org/2001/04/xmldsig-more#hmac-sha256",
                                "http://www.w3.org/2001/04/xmlenc#sha256");

///////////////////////////////////////////////////////////////////
// Create token validation parameters for the signed JWT
// This object will be used to verify the cryptographic signature of the received JWT
TokenValidationParameters validationParams =
    new TokenValidationParameters()
    {
        AllowedAudience = s_jwtAudience,
        ValidIssuer = s_jwtIssuer,
        ValidateExpiration = true,
        ValidateNotBefore = true,
        ValidateIssuer = true,
        ValidateSignature = true,
        SigningToken = new BinarySecretSecurityToken(keyForHmacSha256),
    };

///////////////////////////////////////////////////////////////////
// Create JWT handler
// This object is used to write/sign/decode/validate JWTs
JWTSecurityTokenHandler jwtHandler = new JWTSecurityTokenHandler();

// Create a simple JWT claim set
IList<Claim> payloadClaims = new List<Claim>() { new Claim("clm1", "clm1 value"), };

// Create a JWT with signing credentials and lifetime of 12 hours
JWTSecurityToken jwt =
    new JWTSecurityToken(jwtIssuer, jwtAudience, payloadClaims, sc, DateTime.UtcNow, DateTime.UtcNow.AddHours(12.0));

// Serialize the JWT
// This is how our JWT looks on the wire: <Base64UrlEncoded header>.<Base64UrlEncoded body>.<signature>
string jwtOnTheWire = jwtHandler.WriteToken(jwt);

// Validate the token signature (we provide the shared symmetric key in `validationParams`)
// This will throw if the signature does not validate
jwtHandler.ValidateToken(jwtOnTheWire, validationParams);

// Parse JWT from the Base64UrlEncoded wire form (<Base64UrlEncoded header>.<Base64UrlEncoded body>.<signature>)
JWTSecurityToken parsedJwt = jwtHandler.ReadToken(jwtOnTheWire) as JWTSecurityToken;