Add UpdateError::RollbackProtection

Updating to epoch branch of hubtools. No code impact

Author: lzrd

Cargo.lock

@@ -15,7 +15,9 @@ resolver = "2"
 
 [workspace.dependencies]
 tlvc = { git = "https://github.com/oxidecomputer/tlvc.git", branch = "main" }
-hubtools = { git = "https://github.com/oxidecomputer/hubtools.git", branch = "main"}
+#hubtools = { git = "https://github.com/oxidecomputer/hubtools.git" }
+#hubtools = { git = "https://github.com/oxidecomputer/hubtools.git", branch = "epoch"}
+hubtools = { path = "/home/stoltz/Oxide/src/hubtools/epoch/hubtools" }
 slog-error-chain = { git = "https://github.com/oxidecomputer/slog-error-chain.git", branch = "main", features = ["derive"] }
 
 anyhow = "1.0"

Cargo.toml

@@ -1149,6 +1149,7 @@ pub enum UpdateError {
     ImageMismatch,
     SignatureNotValidated,
     VersionNotSupported,
+    RollbackProtection,
 }
 
 impl fmt::Display for UpdateError {
@@ -1208,6 +1209,9 @@ impl fmt::Display for UpdateError {
             Self::InvalidComponent => {
                 write!(f, "invalid component for operation")
             }
+            Self::RollbackProtection => {
+                write!(f, "invalid epoch compared to active image")
+            }
         }
     }
 }