Add a string getter for the verification key (#14)

* Add a string getter for the verification key, helping this library to dovetail with the rust-ear library.
* Allow clippy multiple_crate_versions checks, because they are triggered through the dependency graph in a way that we can't control.

Signed-off-by: Paul Howard <[email protected]>

c-wrapper/src/lib.rs

@@ -1,6 +1,8 @@
 // Copyright 2022 Contributors to the Veraison project.
 // SPDX-License-Identifier: Apache-2.0
 
+#![allow(clippy::multiple_crate_versions)]
+
 use std::ffi::{c_void, CStr, CString};
 
 use core::slice;

rust-client/src/lib.rs

@@ -1,6 +1,8 @@
 // Copyright 2022 Contributors to the Veraison project.
 // SPDX-License-Identifier: Apache-2.0
 
+#![allow(clippy::multiple_crate_versions)]
+
 #[derive(thiserror::Error, PartialEq, Eq)]
 pub enum Error {
     #[error("configuration error: {0}")]
@@ -345,6 +347,11 @@ impl VerificationApi {
             .map_err(|e| Error::DataConversionError(e.to_string()))
     }
 
+    /// Obtains the EAR verification public key as a JSON string.
+    pub fn ear_verification_key_as_string(&self) -> String {
+        self.ear_verification_key.to_string()
+    }
+
     /// Obtains the signature algorithm scheme used with the EAR.
     pub fn ear_verification_algorithm(&self) -> String {
         match &self.ear_verification_key.algorithm {