openpgp: Use weaker ordering function.

  - Previously, Cert::canonicalize relied on Unknown implenting Ord.
    However, due to streaming, it cannot.  Use a weaker ordering
    function.

1 files changed, 11 insertions, 0 deletions

diff --git a/openpgp/src/packet/unknown.rs b/openpgp/src/packet/unknown.rs
index ed718e1b..adb511bd 100644
--- a/openpgp/src/packet/unknown.rs
+++ b/openpgp/src/packet/unknown.rs
@@ -130,6 +130,17 @@ impl Unknown {
     pub fn set_body(&mut self, data: Vec<u8>) -> Vec<u8> {
         std::mem::replace(&mut self.body, data)
     }
+
+    /// Best effort Ord implementation.
+    ///
+    /// The Cert canonicalization needs to order Unknown packets.
+    /// However, due to potential streaming, Unknown cannot implement
+    /// Eq.  This is cheating a little, we simply ignore the streaming
+    /// case.
+    pub(crate) // For cert/mod.rs
+    fn best_effort_cmp(&self, other: &Unknown) -> Ordering {
+        self.tag.cmp(&other.tag).then_with(|| self.body().cmp(&other.body()))
+    }
 }
 
 impl From<Unknown> for Packet {