Add temp_password_ptr method to AuthenticatedDevice

To reduce the number of casts, we introduce the temp_password_ptr method
that casts the pointer received from the Vec<u8> to a c_char pointer
that can be handled by libnitrokey.

1 files changed, 16 insertions, 8 deletions

diff --git a/src/auth.rs b/src/auth.rs
index d1eb049..541de35 100644
--- a/src/auth.rs
+++ b/src/auth.rs
@@ -111,6 +111,8 @@ pub trait Authenticate {
 
 trait AuthenticatedDevice<T> {
     fn new(device: T, temp_password: Vec<u8>) -> Self;
+
+    fn temp_password_ptr(&self) -> *const c_char;
 }
 
 /// A Nitrokey device with user authentication.
@@ -217,20 +219,19 @@ impl<T: Device> Deref for User<T> {
 impl<T: Device> GenerateOtp for User<T> {
     fn get_hotp_code(&self, slot: u8) -> Result<String, Error> {
         unsafe {
-            let temp_password_ptr = self.temp_password.as_ptr() as *const c_char;
+            let temp_password_ptr = self.temp_password_ptr();
             return result_from_string(nitrokey_sys::NK_get_hotp_code_PIN(slot, temp_password_ptr));
         }
     }
 
     fn get_totp_code(&self, slot: u8) -> Result<String, Error> {
         unsafe {
-            let temp_password_ptr = self.temp_password.as_ptr() as *const c_char;
             return result_from_string(nitrokey_sys::NK_get_totp_code_PIN(
                 slot,
                 0,
                 0,
                 0,
-                temp_password_ptr,
+                self.temp_password_ptr(),
             ));
         }
     }
@@ -243,6 +244,10 @@ impl<T: Device> AuthenticatedDevice<T> for User<T> {
             temp_password,
         }
     }
+
+    fn temp_password_ptr(&self) -> *const c_char {
+        self.temp_password.as_ptr() as *const c_char
+    }
 }
 
 impl<T: Device> Deref for Admin<T> {
@@ -297,7 +302,7 @@ impl<T: Device> Admin<T> {
                 raw_config.scrollock,
                 raw_config.user_password,
                 false,
-                self.temp_password.as_ptr() as *const c_char,
+                self.temp_password_ptr(),
             ))
         }
     }
@@ -307,8 +312,7 @@ impl<T: Device> Admin<T> {
         C: Fn(RawOtpSlotData, *const c_char) -> c_int,
     {
         let raw_data = RawOtpSlotData::new(data)?;
-        let temp_password_ptr = self.temp_password.as_ptr() as *const c_char;
-        get_command_result(callback(raw_data, temp_password_ptr))
+        get_command_result(callback(raw_data, self.temp_password_ptr()))
     }
 }
 
@@ -346,12 +350,12 @@ impl<T: Device> ConfigureOtp for Admin<T> {
     }
 
     fn erase_hotp_slot(&self, slot: u8) -> Result<(), Error> {
-        let temp_password_ptr = self.temp_password.as_ptr() as *const c_char;
+        let temp_password_ptr = self.temp_password_ptr();
         unsafe { get_command_result(nitrokey_sys::NK_erase_hotp_slot(slot, temp_password_ptr)) }
     }
 
     fn erase_totp_slot(&self, slot: u8) -> Result<(), Error> {
-        let temp_password_ptr = self.temp_password.as_ptr() as *const c_char;
+        let temp_password_ptr = self.temp_password_ptr();
         unsafe { get_command_result(nitrokey_sys::NK_erase_totp_slot(slot, temp_password_ptr)) }
     }
 }
@@ -363,6 +367,10 @@ impl<T: Device> AuthenticatedDevice<T> for Admin<T> {
             temp_password,
         }
     }
+
+    fn temp_password_ptr(&self) -> *const c_char {
+        self.temp_password.as_ptr() as *const c_char
+    }
 }
 
 impl Authenticate for DeviceWrapper {