> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cosmos.network/llms.txt
> Use this file to discover all available pages before exploring further.

# Changelog

> Release history and changelog for Cosmos IBC

<Info>
  This page tracks all releases and changes from the [cosmos/ibc-go](https://github.com/cosmos/ibc-go) repository.
  For the latest development updates, see the [UNRELEASED](https://github.com/cosmos/ibc-go/blob/main/CHANGELOG.md#unreleased) section.
</Info>

<Update label="2023-10-20" description="v6.2.1" tags={["IBC", "Release"]}>
  ## Bug Fixes

  * (apps/transfer) [#3045](https://github.com/cosmos/ibc-go/pull/3045) allow value with slashes in URL template for `denom_traces` and `denom_hashes` queries.
  * (apps/transfer) [#4709](https://github.com/cosmos/ibc-go/pull/4709) Order query service RPCs to fix availability of denom traces endpoint when no args are provided.
</Update>

<Update label="2023-05-31" description="v6.2.0" tags={["IBC", "Release"]}>
  ## Dependencies

  * [#3393](https://github.com/cosmos/ibc-go/pull/3393) Bump Cosmos SDK to v0.46.12 and replace Tendermint with CometBFT v0.34.37.

  ## Improvements

  * (core) [#3082](https://github.com/cosmos/ibc-go/pull/3082) Add `HasConnection` and `HasChannel` methods.
  * (apps/transfer) [#3454](https://github.com/cosmos/ibc-go/pull/3454) Support transfer authorization unlimited spending when the max `uint256` value is provided as limit.

  ## Features

  * [#3079](https://github.com/cosmos/ibc-go/pull/3079) Add authz support for ics20.

  ## Bug Fixes

  * [#3346](https://github.com/cosmos/ibc-go/pull/3346) Properly handle ordered channels in `UnreceivedPackets` query.
</Update>

<Update label="2023-10-20" description="v6.1.2" tags={["IBC", "Release"]}>
  ## Bug Fixes

  * (apps/transfer) [#3045](https://github.com/cosmos/ibc-go/pull/3045) allow value with slashes in URL template for `denom_traces` and `denom_hashes` queries.
  * (apps/transfer) [#4709](https://github.com/cosmos/ibc-go/pull/4709) Order query service RPCs to fix availability of denom traces endpoint when no args are provided.
</Update>

<Update label="2023-05-25" description="v6.1.1" tags={["IBC", "Release"]}>
  ## Bug Fixes

  * [#3346](https://github.com/cosmos/ibc-go/pull/3346) Properly handle ordered channels in `UnreceivedPackets` query.
</Update>

<Update label="2022-12-20" description="v6.1.0" tags={["IBC", "Release"]}>
  ## Dependencies

  * [#2945](https://github.com/cosmos/ibc-go/pull/2945) Bump Cosmos SDK to v0.46.7 and Tendermint to v0.34.24.

  ## State Machine Breaking

  * (apps/29-fee) [#2942](https://github.com/cosmos/ibc-go/pull/2942) Check `x/bank` send enabled before escrowing fees.
</Update>

<Update label="2022-12-09" description="v6.0.0" tags={["IBC", "Release"]}>
  ## Dependencies

  * [#2868](https://github.com/cosmos/ibc-go/pull/2868) Bump ICS 23 to v0.9.0.
  * [#2458](https://github.com/cosmos/ibc-go/pull/2458) Bump Cosmos SDK to v0.46.2
  * [#2784](https://github.com/cosmos/ibc-go/pull/2784) Bump Cosmos SDK to v0.46.6 and Tendermint to v0.34.23.

  ## API Breaking

  * (apps/27-interchain-accounts) [#2607](https://github.com/cosmos/ibc-go/pull/2607) `SerializeCosmosTx` now takes in a `[]proto.Message` instead of `[]sdk.Msg`.
  * (apps/transfer) [#2446](https://github.com/cosmos/ibc-go/pull/2446) Remove `SendTransfer` function in favor of a private `sendTransfer` function. All IBC transfers must be initiated with `MsgTransfer`.
  * (apps/29-fee) [#2395](https://github.com/cosmos/ibc-go/pull/2395) Remove param space from ics29 NewKeeper function. The field was unused.
  * (apps/27-interchain-accounts) [#2133](https://github.com/cosmos/ibc-go/pull/2133) Generates genesis protos in a separate directory to avoid circular import errors. The protobuf package name has changed for the genesis types.
  * (apps/27-interchain-accounts) [#2638](https://github.com/cosmos/ibc-go/pull/2638) Interchain accounts host and controller Keepers now expects a keeper which fulfills the expected `exported.ScopedKeeper` interface for the capability keeper.
  * (transfer) [#2638](https://github.com/cosmos/ibc-go/pull/2638) Transfer Keeper now expects a keeper which fulfills the expected `exported.ScopedKeeper` interface for the capability keeper.
  * (05-port) [#2638](https://github.com/cosmos/ibc-go/pull/2638) Port Keeper now expects a keeper which fulfills the expected `exported.ScopedKeeper` interface for the capability keeper.
  * (04-channel) [#2638](https://github.com/cosmos/ibc-go/pull/2638) Channel Keeper now expects a keeper which fulfills the expected `exported.ScopedKeeper` interface for the capability keeper.
  * (core/04-channel)[#1703](https://github.com/cosmos/ibc-go/pull/1703) Update `SendPacket` API to take in necessary arguments and construct rest of packet rather than taking in entire packet. The generated packet sequence is returned by the `SendPacket` function.
  * (modules/apps/27-interchain-accounts) [#2433](https://github.com/cosmos/ibc-go/pull/2450) Renamed icatypes.PortPrefix to icatypes.ControllerPortPrefix & icatypes.PortID to icatypes.HostPortID
  * (testing) [#2567](https://github.com/cosmos/ibc-go/pull/2567) Modify `SendPacket` API of `Endpoint` to match the API of `SendPacket` in 04-channel.

  ## State Machine Breaking

  * (apps/transfer) [#2651](https://github.com/cosmos/ibc-go/pull/2651) Introduce `mustProtoMarshalJSON` for ics20 packet data marshalling which will skip emission (marshalling) of the memo field if unpopulated (empty).
  * (27-interchain-accounts) [#2590](https://github.com/cosmos/ibc-go/pull/2590) Removing port prefix requirement from the ICA host channel handshake
  * (transfer) [#2377](https://github.com/cosmos/ibc-go/pull/2377) Adding `sequence` to `MsgTransferResponse`.
  * (light-clients/07-tendermint) [#2555](https://github.com/cosmos/ibc-go/pull/2555) Forbid negative values for `TrustingPeriod`, `UnbondingPeriod` and `MaxClockDrift` (as specified in ICS-07).
  * (core/04-channel) [#2973](https://github.com/cosmos/ibc-go/pull/2973) Write channel state before invoking app callbacks in ack and confirm channel handshake steps.

  ## Improvements

  * (apps/27-interchain-accounts) [#2134](https://github.com/cosmos/ibc-go/pull/2134) Adding upgrade handler to ICS27 `controller` submodule for migration of channel capabilities. This upgrade handler migrates ownership of channel capabilities from the underlying application to the ICS27 `controller` submodule.
  * (apps/27-interchain-accounts) [#2102](https://github.com/cosmos/ibc-go/pull/2102) ICS27 controller middleware now supports a nil underlying application. This allows chains to make use of interchain accounts with existing auth mechanisms such as x/group and x/gov.
  * (apps/27-interchain-accounts) [#2157](https://github.com/cosmos/ibc-go/pull/2157) Adding `IsMiddlewareEnabled` functionality to enforce calls to ICS27 msg server to *not* route to the underlying application.
  * (apps/27-interchain-accounts) [#2146](https://github.com/cosmos/ibc-go/pull/2146) ICS27 controller now claims the channel capability passed via ibc core, and passes `nil` to the underlying app callback. The channel capability arg in `SendTx` is now ignored and looked up internally.
  * (apps/27-interchain-accounts) [#2177](https://github.com/cosmos/ibc-go/pull/2177) Adding `IsMiddlewareEnabled` flag to interchain accounts `ActiveChannel` genesis type.
  * (apps/27-interchain-accounts) [#2140](https://github.com/cosmos/ibc-go/pull/2140) Adding migration handler to ICS27 `controller` submodule to assert ownership of channel capabilities and set middleware enabled flag for existing channels. The ICS27 module consensus version has been bumped from 1 to 2.
  * (core/04-channel) [#2304](https://github.com/cosmos/ibc-go/pull/2304) Adding `GetAllChannelsWithPortPrefix` function which filters channels based on a provided port prefix.
  * (apps/27-interchain-accounts) [#2248](https://github.com/cosmos/ibc-go/pull/2248) Adding call to underlying app in `OnChanCloseConfirm` callback of the controller submodule and adding relevant unit tests.
  * (apps/27-interchain-accounts) [#2251](https://github.com/cosmos/ibc-go/pull/2251) Adding `msgServer` struct to controller submodule that embeds the `Keeper` struct.
  * (apps/27-interchain-accounts) [#2290](https://github.com/cosmos/ibc-go/pull/2290) Changed `DefaultParams` function in `host` submodule to allow all messages by default. Defined a constant named `AllowAllHostMsgs` for `host` module to keep wildcard "\*" string which allows all messages.
  * (apps/27-interchain-accounts) [#2297](https://github.com/cosmos/ibc-go/pull/2297) Adding cli command to generate ICS27 packet data.
  * (modules/core/keeper) [#1728](https://github.com/cosmos/ibc-go/pull/2399) Updated channel callback errors to include portID & channelID for better identification of errors.
  * (testing) [#2657](https://github.com/cosmos/ibc-go/pull/2657) Carry `ProposerAddress` through committed blocks. Allow `DefaultGenTxGas` to be modified.
  * (core/03-connection) [#2745](https://github.com/cosmos/ibc-go/pull/2745) Adding `ConnectionParams` grpc query and CLI to 03-connection.
  * (apps/29-fee) [#2786](https://github.com/cosmos/ibc-go/pull/2786) Save gas by checking key existence with `KVStore`'s `Has` method.

  ## Features

  * (apps/27-interchain-accounts) [#2147](https://github.com/cosmos/ibc-go/pull/2147) Adding a `SubmitTx` gRPC endpoint for the ICS27 Controller module which allows owners of interchain accounts to submit transactions. This replaces the previously existing need for authentication modules to implement this standard functionality.
  * (testing/simapp) [#2190](https://github.com/cosmos/ibc-go/pull/2190) Adding the new `x/group` cosmos-sdk module to simapp.
  * (apps/transfer) [#2595](https://github.com/cosmos/ibc-go/pull/2595) Adding optional memo field to `FungibleTokenPacketData` and `MsgTransfer`.

  ## Bug Fixes

  * (modules/core/keeper) [#2403](https://github.com/cosmos/ibc-go/pull/2403) Added a function in keeper to cater for blank pointers.
  * (apps/transfer) [#2679](https://github.com/cosmos/ibc-go/pull/2679) Check `x/bank` send enabled.
  * (modules/core/keeper) [#2745](https://github.com/cosmos/ibc-go/pull/2745) Fix request wiring for `UpgradedConsensusState` in core query server.
</Update>