From 76a2d832b3b7e5336b130b1fe9aae9a548502737 Mon Sep 17 00:00:00 2001
From: Ben Stoltz <ben.stoltz@oxidecomputer.com>
Date: Mon, 9 Jun 2025 12:55:09 -0700
Subject: [PATCH] Add InvalidPreferredSlotId error for use in rot
 prep_image_update

---
 gateway-messages/src/sp_to_mgs.rs        |  7 ++
 gateway-messages/tests/versioning/v19.rs | 84 ++++++++++++++++++++++++
 gateway-sp-comms/src/error.rs            |  2 +
 3 files changed, 93 insertions(+)

diff --git a/gateway-messages/src/sp_to_mgs.rs b/gateway-messages/src/sp_to_mgs.rs
index c5d1da72..d4427670 100644
--- a/gateway-messages/src/sp_to_mgs.rs
+++ b/gateway-messages/src/sp_to_mgs.rs
@@ -1294,6 +1294,7 @@ pub enum UpdateError {
     ImageMismatch,
     SignatureNotValidated,
     VersionNotSupported,
+    InvalidPreferredSlotId,
 }
 
 impl fmt::Display for UpdateError {
@@ -1353,6 +1354,12 @@ impl fmt::Display for UpdateError {
             Self::InvalidComponent => {
                 write!(f, "invalid component for operation")
             }
+            Self::InvalidPreferredSlotId => {
+                write!(
+                    f,
+                    "updating a bootloader preferred slot is not permitted"
+                )
+            }
         }
     }
 }
diff --git a/gateway-messages/tests/versioning/v19.rs b/gateway-messages/tests/versioning/v19.rs
index f724fa64..845abe9d 100644
--- a/gateway-messages/tests/versioning/v19.rs
+++ b/gateway-messages/tests/versioning/v19.rs
@@ -16,6 +16,9 @@
 //! tests can be removed as we will stop supporting $VERSION.
 
 use super::assert_serialized;
+use gateway_messages::ImageError;
+use gateway_messages::SpStateV3;
+use gateway_messages::UpdateError;
 use gateway_messages::{HfError, MgsRequest, SpError, SpResponse};
 
 #[test]
@@ -60,3 +63,84 @@ fn read_host_flash() {
         assert_serialized(&[38, i as u8], &request);
     }
 }
+
+#[test]
+fn sp_response() {
+    let response = SpResponse::SpStateV3(SpStateV3 {
+        hubris_archive_id: [1, 2, 3, 4, 5, 6, 7, 8],
+        serial_number: [
+            9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,
+            26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
+        ],
+        model: [
+            41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,
+            58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72,
+        ],
+        revision: 0xf0f1f2f3,
+        base_mac_address: [73, 74, 75, 76, 77, 78],
+        power_state: gateway_messages::PowerState::A0,
+    });
+
+    #[rustfmt::skip]
+    let expected = vec![
+        44, // SpStateV3
+        1, 2, 3, 4, 5, 6, 7, 8, // hubris_archive_id
+
+        9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
+        24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,
+        39, 40, // serial_number
+
+        41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,
+        56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70,
+        71, 72, // model
+
+        0xf3, 0xf2, 0xf1, 0xf0, // revision
+        73, 74, 75, 76, 77, 78, // base_mac_address
+        0, // power_state
+    ];
+
+    assert_serialized(&expected, &response);
+}
+
+#[test]
+fn host_request() {
+    let request = MgsRequest::VersionedRotBootInfo { version: 3 };
+
+    #[rustfmt::skip]
+    let expected = vec![
+        45, // VersionedRotBootInfo
+        3, // version
+    ];
+
+    assert_serialized(&expected, &request);
+}
+
+#[test]
+fn error_enums() {
+    let response: [ImageError; 13] = [
+        ImageError::Unchecked,
+        ImageError::FirstPageErased,
+        ImageError::PartiallyProgrammed,
+        ImageError::InvalidLength,
+        ImageError::HeaderNotProgrammed,
+        ImageError::BootloaderTooSmall,
+        ImageError::BadMagic,
+        ImageError::HeaderImageSize,
+        ImageError::UnalignedLength,
+        ImageError::UnsupportedType,
+        ImageError::ResetVectorNotThumb2,
+        ImageError::ResetVector,
+        ImageError::Signature,
+    ];
+    let expected = vec![0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12];
+    assert_serialized(&expected, &response);
+
+    let response: [UpdateError; 4] = [
+        UpdateError::BlockOutOfOrder,
+        UpdateError::InvalidComponent,
+        UpdateError::InvalidSlotIdForOperation,
+        UpdateError::InvalidPreferredSlotId,
+    ];
+    let expected = vec![27, 28, 29, 34];
+    assert_serialized(&expected, &response);
+}
diff --git a/gateway-sp-comms/src/error.rs b/gateway-sp-comms/src/error.rs
index 8c45978e..1b3273bb 100644
--- a/gateway-sp-comms/src/error.rs
+++ b/gateway-sp-comms/src/error.rs
@@ -116,6 +116,8 @@ pub enum UpdateError {
     InvalidComponent,
     #[error("an image was not found")]
     ImageNotFound,
+    #[error("updating a bootloader preferred slot is not permitted")]
+    InvalidPreferredSlotId,
 }
 
 #[derive(Debug, thiserror::Error, SlogInlineError)]