Backport bug fixes from upstream. Wrong seq encoding

ibc-core/ics04-channel/src/handler/timeout.rs

@@ -230,23 +230,12 @@ where
             let seq_recv_path_on_b =
                 SeqRecvPath::new(&msg.packet.port_id_on_b, &msg.packet.chan_id_on_b);
 
-            // let mut value = Vec::new();
-            // u64::from(msg.packet.seq_on_a)
-            //     .encode(&mut value)
-            //     .map_err(|_| PacketError::CannotEncodeSequence {
-            //         sequence: msg.packet.seq_on_a,
-            //     })?;
-
-            // Note: We expect the return to be a u64 encoded in big-endian. Refer to ibc-go:
-            // https://github.com/cosmos/ibc-go/blob/25767f6bdb5bab2c2a116b41d92d753c93e18121/modules/core/04-channel/client/utils/utils.go#L191
-            let value = u64::from(msg.packet.seq_on_a).to_be_bytes().to_vec();
-
             client_state_of_b_on_a.verify_membership(
                 conn_end_on_a.counterparty().prefix(),
                 &msg.proof_unreceived_on_b,
                 consensus_state_of_b_on_a.root(),
                 Path::SeqRecv(seq_recv_path_on_b),
-                value,
+                msg.packet.seq_on_a.to_vec(),
             )
         } else {
             let receipt_path_on_b = ReceiptPath::new(

ibc-core/ics04-channel/src/handler/timeout_on_close.rs

@@ -13,7 +13,6 @@ use ibc_core_host::types::path::{
 use ibc_core_host::ValidationContext;
 use ibc_primitives::prelude::*;
 use ibc_primitives::proto::Protobuf;
-use prost::Message;
 
 pub fn validate<Ctx>(ctx_a: &Ctx, msg: &MsgTimeoutOnClose) -> Result<(), ContextError>
 where
@@ -135,19 +134,12 @@ where
             }
             let seq_recv_path_on_b = SeqRecvPath::new(&packet.port_id_on_b, &packet.chan_id_on_b);
 
-            let mut value = Vec::new();
-            u64::from(packet.seq_on_a).encode(&mut value).map_err(|_| {
-                PacketError::CannotEncodeSequence {
-                    sequence: packet.seq_on_a,
-                }
-            })?;
-
             client_state_of_b_on_a.verify_membership(
                 conn_end_on_a.counterparty().prefix(),
                 &msg.proof_unreceived_on_b,
                 consensus_state_of_b_on_a.root(),
                 Path::SeqRecv(seq_recv_path_on_b),
-                value,
+                packet.seq_on_a.to_vec(),
             )
         } else {
             let receipt_path_on_b = ReceiptPath::new(

ibc-core/ics24-host/types/src/identifiers/sequence.rs

@@ -44,6 +44,11 @@ impl Sequence {
     pub fn increment(&self) -> Sequence {
         Sequence(self.0 + 1)
     }
+
+    /// Encodes the sequence number into a byte array in big endian.
+    pub fn to_vec(&self) -> Vec<u8> {
+        self.0.to_be_bytes().to_vec()
+    }
 }
 
 impl From<u64> for Sequence {