From 4ba644827d68db6450ec5883223f43cb31ddac19 Mon Sep 17 00:00:00 2001
From: Rayhaan Jaufeerally <rayhaan+github@rayhaan.ch>
Date: Sat, 18 Apr 2026 13:22:24 +0200
Subject: [PATCH] Error codes cleanup & typo fix

---
 crates/packet/src/errors.rs  | 40 +++++++++++++++++++++++++++---------
 crates/packet/src/message.rs |  9 ++------
 2 files changed, 32 insertions(+), 17 deletions(-)

diff --git a/crates/packet/src/errors.rs b/crates/packet/src/errors.rs
index 246e997..aea255e 100644
--- a/crates/packet/src/errors.rs
+++ b/crates/packet/src/errors.rs
@@ -2,6 +2,13 @@ use serde::{Deserialize, Serialize};
 use strum::FromRepr;
 use thiserror::Error;
 
+#[derive(Debug, Error)]
+#[error("Unknown BGP error code {code} subcode {subcode}")]
+pub struct UnknownErrorCode {
+    pub code: u8,
+    pub subcode: u8,
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, Error, Serialize, Deserialize)]
 #[repr(u8)]
 pub enum BgpError {
@@ -31,17 +38,30 @@ pub enum BgpError {
 }
 
 impl BgpError {
-    pub fn from_code_subcode(code: u8, subcode: u8) -> Result<Self, ()> {
+    pub fn from_code_subcode(code: u8, subcode: u8) -> Result<Self, UnknownErrorCode> {
+        let err = || UnknownErrorCode { code, subcode };
         match code {
-            1 => Ok(Self::MsgHeader(MsgHeaderSubcode::try_from(subcode)?)),
-            2 => Ok(Self::OpenMsg(OpenMsgSubcode::try_from(subcode)?)),
-            3 => Ok(Self::UpdateMsg(UpdateMsgSubcode::try_from(subcode)?)),
+            1 => Ok(Self::MsgHeader(
+                MsgHeaderSubcode::try_from(subcode).map_err(|_| err())?,
+            )),
+            2 => Ok(Self::OpenMsg(
+                OpenMsgSubcode::try_from(subcode).map_err(|_| err())?,
+            )),
+            3 => Ok(Self::UpdateMsg(
+                UpdateMsgSubcode::try_from(subcode).map_err(|_| err())?,
+            )),
             4 => Ok(Self::HoldTimer),
-            5 => Ok(Self::FsmError(FsmSubcode::try_from(subcode)?)),
-            6 => Ok(Self::Cease(CeaseSubcode::try_from(subcode)?)),
-            7 => Ok(Self::RouteRefresh(RouteRefreshSubcode::try_from(subcode)?)),
+            5 => Ok(Self::FsmError(
+                FsmSubcode::try_from(subcode).map_err(|_| err())?,
+            )),
+            6 => Ok(Self::Cease(
+                CeaseSubcode::try_from(subcode).map_err(|_| err())?,
+            )),
+            7 => Ok(Self::RouteRefresh(
+                RouteRefreshSubcode::try_from(subcode).map_err(|_| err())?,
+            )),
             8 => Ok(Self::SendHoldTimer),
-            _ => Err(()),
+            _ => Err(err()),
         }
     }
 
@@ -69,7 +89,7 @@ pub enum MsgHeaderSubcode {
     BadMessageLength = 2,
 
     #[error("Bad message type")]
-    BadMessagType = 3,
+    BadMessageType = 3,
 }
 
 impl TryFrom<u8> for MsgHeaderSubcode {
@@ -115,7 +135,7 @@ impl TryFrom<u8> for OpenMsgSubcode {
 #[repr(u8)]
 pub enum UpdateMsgSubcode {
     #[error("Malformed attribute list")]
-    MalforedAttrs = 1,
+    MalformedAttrs = 1,
 
     #[error("Unrecognized well known attribute")]
     UnrecognizedWellKnownAttr = 2,
diff --git a/crates/packet/src/message.rs b/crates/packet/src/message.rs
index 8e0bf93..d009cf5 100644
--- a/crates/packet/src/message.rs
+++ b/crates/packet/src/message.rs
@@ -1443,13 +1443,8 @@ impl NotificationMessage {
         let (buf, error_code) = be_u8(buf)?;
         let (buf, error_subcode) = be_u8(buf)?;
 
-        let error = BgpError::from_code_subcode(error_code, error_subcode).map_err(|_| {
-            Failure(BgpParserError::Eyre(eyre!(
-                "Unknown NOTIFICATION error code {} subcode {}",
-                error_code,
-                error_subcode
-            )))
-        })?;
+        let error = BgpError::from_code_subcode(error_code, error_subcode)
+            .map_err(|e| Failure(BgpParserError::Eyre(e.into())))?;
 
         Ok((&[], Self { error, data: buf.to_vec() }))
     }