[rkp] Add request/response for certificate request generation

This cl adds the request and response protocol for the
certificate request generation. It is needed by the
IRemotelyProvisionedComponent implementation in AVF.

Bug: 299256925
Test: atest rialto_test
Change-Id: I77833c24834c8e697b066dbb070b364dad626b6c
diff --git a/rialto/src/requests/api.rs b/rialto/src/requests/api.rs
index 05a386e..c4b2d8e 100644
--- a/rialto/src/requests/api.rs
+++ b/rialto/src/requests/api.rs
@@ -29,6 +29,10 @@
             let res = rkp::generate_ecdsa_p256_key_pair()?;
             Response::GenerateEcdsaP256KeyPair(res)
         }
+        Request::GenerateCertificateRequest(p) => {
+            let res = rkp::generate_certificate_request(p)?;
+            Response::GenerateCertificateRequest(res)
+        }
     };
     Ok(response)
 }
diff --git a/rialto/src/requests/rkp.rs b/rialto/src/requests/rkp.rs
index f1b1b17..5977bfb 100644
--- a/rialto/src/requests/rkp.rs
+++ b/rialto/src/requests/rkp.rs
@@ -17,10 +17,17 @@
 
 use crate::error::Result;
 use alloc::vec::Vec;
-use service_vm_comm::EcdsaP256KeyPair;
+use service_vm_comm::{EcdsaP256KeyPair, GenerateCertificateRequestParams};
 
 pub(super) fn generate_ecdsa_p256_key_pair() -> Result<EcdsaP256KeyPair> {
     // TODO(b/299055662): Generate the key pair.
     let key_pair = EcdsaP256KeyPair { maced_public_key: Vec::new(), key_blob: Vec::new() };
     Ok(key_pair)
 }
+
+pub(super) fn generate_certificate_request(
+    _params: GenerateCertificateRequestParams,
+) -> Result<Vec<u8>> {
+    // TODO(b/299256925): Generate the certificate request
+    Ok(Vec::new())
+}