Add test_helpers (#474)

* Add set_enterprise_attestation in TestEnv

* Add test_helpers for Test Unification

* Used it in structured fuzzer and enterprise attestation unittests

* Restructure test_helpers

* Rename setup_enterprise_attestation to enable_

src/test_helpers/mod.rs

@@ -0,0 +1,48 @@
+use crate::clock::CtapInstant;
+use crate::ctap::command::{
+    AuthenticatorAttestationMaterial, AuthenticatorConfigParameters,
+    AuthenticatorVendorConfigureParameters, Command,
+};
+use crate::ctap::data_formats::ConfigSubCommand;
+use crate::ctap::status_code::Ctap2StatusCode;
+use crate::ctap::{key_material, Channel, CtapState};
+use crate::env::Env;
+
+// In tests where we define a dummy user-presence check that immediately returns, the channel
+// ID is irrelevant, so we pass this (dummy but valid) value.
+const DUMMY_CHANNEL: Channel = Channel::MainHid([0x12, 0x34, 0x56, 0x78]);
+#[cfg(feature = "vendor_hid")]
+const VENDOR_CHANNEL: Channel = Channel::VendorHid([0x12, 0x34, 0x56, 0x78]);
+
+pub fn enable_enterprise_attestation(
+    state: &mut CtapState,
+    env: &mut impl Env,
+) -> Result<AuthenticatorAttestationMaterial, Ctap2StatusCode> {
+    let dummy_key = [0x41; key_material::ATTESTATION_PRIVATE_KEY_LENGTH];
+    let dummy_cert = vec![0xdd; 20];
+    let attestation_material = AuthenticatorAttestationMaterial {
+        certificate: dummy_cert,
+        private_key: dummy_key,
+    };
+    let configure_params = AuthenticatorVendorConfigureParameters {
+        lockdown: false,
+        attestation_material: Some(attestation_material.clone()),
+    };
+    #[cfg(feature = "vendor_hid")]
+    let vendor_channel = VENDOR_CHANNEL;
+    #[cfg(not(feature = "vendor_hid"))]
+    let vendor_channel = DUMMY_CHANNEL;
+    let vendor_command = Command::AuthenticatorVendorConfigure(configure_params);
+    state.process_parsed_command(env, vendor_command, vendor_channel, CtapInstant::new(0))?;
+
+    let config_params = AuthenticatorConfigParameters {
+        sub_command: ConfigSubCommand::EnableEnterpriseAttestation,
+        sub_command_params: None,
+        pin_uv_auth_param: None,
+        pin_uv_auth_protocol: None,
+    };
+    let config_command = Command::AuthenticatorConfig(config_params);
+    state.process_parsed_command(env, config_command, DUMMY_CHANNEL, CtapInstant::new(0))?;
+
+    Ok(attestation_material)
+}