sample: always enable sample attester

Rather than setting an environment variable to enable
the sample attester, always enable it as a fallback.

Signed-off-by: Tobin Feldman-Fitzthum <[email protected]>

attestation-agent/attester/src/lib.rs

@@ -78,10 +78,6 @@ pub trait Attester {
 
 // Detect which TEE platform the KBC running environment is.
 pub fn detect_tee_type() -> Option<Tee> {
-    if sample::detect_platform() {
-        return Some(Tee::Sample);
-    }
-
     #[cfg(feature = "tdx-attester")]
     if tdx::detect_platform() {
         return Some(Tee::Tdx);
@@ -117,5 +113,10 @@ pub fn detect_tee_type() -> Option<Tee> {
         return Some(Tee::Cca);
     }
 
+    // Always detected
+    if sample::detect_platform() {
+        return Some(Tee::Sample);
+    }
+
     None
 }

attestation-agent/attester/src/sample/mod.rs

@@ -7,12 +7,10 @@ use super::Attester;
 use anyhow::*;
 use base64::Engine;
 use serde::{Deserialize, Serialize};
-use std::env;
 
-// If the environment variable "AA_SAMPLE_ATTESTER_TEST" is set,
-// the TEE platform is considered as "sample".
+// Sample attester is always supported
 pub fn detect_platform() -> bool {
-    env::var("AA_SAMPLE_ATTESTER_TEST").is_ok()
+    true
 }
 
 // A simple example of TEE evidence.