如何在找到对象后更新特定属性。获取错误方法 C_SetAttributeValue 返回 CKR_ATTRIBUTE_READ_ONLY

Question

我正在尝试在找到对象后更新属性。尝试过不同的案例。

我的创作代码：

using (var pkcs11 = new Pkcs11(@"C:\SoftHSM2\lib\softhsm2.dll", AppType.SingleThreaded))
{
    var slot = pkcs11.GetSlotList(SlotsType.WithTokenPresent)[0];
    using (var session = slot.OpenSession(SessionType.ReadWrite))
    {
        session.Login(CKU.CKU_USER, "1111");
        var objectAttributes = new List<ObjectAttribute>
        {
            new ObjectAttribute(CKA.CKA_CLASS, CKO.CKO_DATA),
            new ObjectAttribute(CKA.CKA_TOKEN, true),
            new ObjectAttribute(CKA.CKA_MODIFIABLE, true),
            new ObjectAttribute(CKA.CKA_APPLICATION, txtTypeofData.Text),
            new ObjectAttribute(CKA.CKA_LABEL,txtMsisdn.Text),
            new ObjectAttribute(CKA.CKA_VALUE, "Data object content original " + DateTime.Now)
        };
        var result = session.CreateObject(objectAttributes);
        session.Logout();
    }
}

我的修改代码是：

using (Pkcs11 pkcs11 = new Pkcs11(@"C:\SoftHSM2\lib\softhsm2.dll", AppType.MultiThreaded))
{            
    var slot = pkcs11.GetSlotList(SlotsType.WithTokenPresent)[0];
    using (Session session = slot.OpenSession(SessionType.ReadWrite))
    {
        session.Login(CKU.CKU_USER, "1111");
        List<ObjectAttribute> objectAttributes = new List<ObjectAttribute>();
        objectAttributes.Add(new ObjectAttribute(CKA.CKA_CLASS, CKO.CKO_DATA));
        objectAttributes.Add(new ObjectAttribute(CKA.CKA_TOKEN, true));
        objectAttributes.Add(new ObjectAttribute(CKA.CKA_APPLICATION, txtTypeofData.Text));
        objectAttributes.Add(new ObjectAttribute(CKA.CKA_LABEL, txtMsisdn.Text));
        objectAttributes.Add(new ObjectAttribute(CKA.CKA_MODIFIABLE, true));

        var findA = session.FindAllObjects(objectAttributes);
        if(findA != null && findA.Count > 0)
        {
            List<ObjectAttribute> objectAttributesNew = new List<ObjectAttribute>();
            objectAttributesNew.Add(new ObjectAttribute(CKA.CKA_VALUE, "Data object content two changed " + DateTime.Now));
            session.SetAttributeValue(findA[0], objectAttributesNew);                        
        }                   
        session.Logout();
    }
}

Answer 1

检查 CKA_MODIFIABLE 是否设置为 TRUE，因为此属性指示数据对象是否为只读。 CKA_MODIFIABLE 默认为 TRUE，只能通过复制对象进行更改。

此外，请注意 PKCS#11 标准中的注释：

attributes which Cryptoki specifies are modifiable may actually not be modifiable on some tokens. That is, if a Cryptoki attribute is described as being modifiable, that really means only that it is modifiable insofar as the Cryptoki specification is concerned. A particular token might not actually support modification of some such attributes.

因此，可能是令牌不允许您更改属性，这不是您的代码的问题。

Answer 2

您观察到的行为似乎特定于 SoftHSM 实现。您可以在其源代码中找到following comment：

// NOTE: There is no mention in the PKCS#11 v2.40 spec that for a Data
//  Object the CKA_VALUE attribute may be modified after creation!
//  Therefore we assume it is not allowed to change the CKA_VALUE
//  attribute of a Data Object.

如何在找到对象后更新特定属性。获取错误方法 C_SetAttributeValue 返回 CKR_ATTRIBUTE_READ_ONLY

How to Update particular Attribute after finding an object. getting error Method C_SetAttributeValue returned CKR_ATTRIBUTE_READ_ONLY

c#

.net

pkcs#11

pkcs11interop

softhsm