KBS: return more context about RCAR/Attestation error

Before this commit, if the rcar auth fails, the client would only get
error information "Attestation error". This commit expose more error
information to the client side. A typical error would say
"Attestation error: RCAR handshake Auth failed: KBS Client Protocol
Version Mismatch: ..."

This would do much help to debugging and error locating.

Signed-off-by: Xynnn007 <[email protected]>

kbs/src/attestation/backend.rs

@@ -181,7 +181,7 @@ impl AttestationService {
         let version = Version::parse(&request.version).context("failed to parse KBS version")?;
         if !VERSION_REQ.matches(&version) {
             bail!(
-                "expected version: {}, requested version: {}",
+                "KBS Client Protocol Version Mismatch: expect {} while the request is {}",
                 *VERSION_REQ,
                 request.version
             );
@@ -191,9 +191,9 @@ impl AttestationService {
             .inner
             .generate_challenge(request.tee, request.extra_params.clone())
             .await
-            .context("generate challenge")?;
+            .context("Attestation Service generate challenge failed")?;
 
-        let session = SessionStatus::auth(request, self.timeout, challenge).context("Session")?;
+        let session = SessionStatus::auth(request, self.timeout, challenge);
 
         let response = HttpResponse::Ok()
             .cookie(session.cookie())

kbs/src/attestation/error.rs

@@ -22,7 +22,7 @@ pub enum Error {
         source: anyhow::Error,
     },
 
-    #[error("RCAR handshake Auth failed")]
+    #[error("RCAR handshake Auth failed: {source}")]
     RcarAuthFailed {
         #[source]
         source: anyhow::Error,

kbs/src/attestation/session.rs

@@ -6,7 +6,6 @@ use actix_web::cookie::{
     time::{Duration, OffsetDateTime},
     Cookie,
 };
-use anyhow::Result;
 use kbs_types::{Challenge, Request};
 use log::warn;
 use uuid::Uuid;
@@ -49,17 +48,17 @@ macro_rules! impl_member {
 }
 
 impl SessionStatus {
-    pub fn auth(request: Request, timeout: i64, challenge: Challenge) -> Result<Self> {
+    pub fn auth(request: Request, timeout: i64, challenge: Challenge) -> Self {
         let id = Uuid::new_v4().as_simple().to_string();
 
         let timeout = OffsetDateTime::now_utc() + Duration::minutes(timeout);
 
-        Ok(Self::Authed {
+        Self::Authed {
             request,
             challenge,
             id,
             timeout,
-        })
+        }
     }
 
     pub fn cookie<'a>(&self) -> Cookie<'a> {

kbs/src/error.rs

@@ -18,11 +18,11 @@ pub type Result<T> = std::result::Result<T, Error>;
 
 #[derive(Error, AsRefStr, Debug)]
 pub enum Error {
-    #[error("Admin auth error")]
+    #[error("Admin auth error: {0}")]
     AdminAuth(#[from] crate::admin::Error),
 
     #[cfg(feature = "as")]
-    #[error("Attestation error")]
+    #[error("Attestation error: {0}")]
     AttestationError(#[from] crate::attestation::Error),
 
     #[error("HTTP initialization failed")]