Support vendor extensions for CK_USER_TYPE

Some HSM vendors have more user types than the standard CKU_SO and
CKU_USER. For example a Thales Luna uses the value 0x80000001 to
represent the unprivileged Crypto User.

Signed-off-by: Lars Persson <larper@axis.com>

Author: larper2axis

cryptoki/src/session/mod.rs

@@ -90,6 +90,8 @@ pub enum UserType {
     User,
     /// Context Specific
     ContextSpecific,
+    /// Vendor extension
+    VendorExtension(u32)
 }
 
 impl From<UserType> for CK_USER_TYPE {
@@ -98,6 +100,7 @@ impl From<UserType> for CK_USER_TYPE {
             UserType::So => CKU_SO,
             UserType::User => CKU_USER,
             UserType::ContextSpecific => CKU_CONTEXT_SPECIFIC,
+            UserType::VendorExtension(n) => n as CK_USER_TYPE
         }
     }
 }