Tracking issue: IBC Implementation

[avahowell]

This is a tracking issue for the high-level items required to reach our MVP3: integration of the IBC protocol for bridging assets in and out of Penumbra.

Prerequisites for mplementing the IBC protocol on Penumbra

• [x] ICS-23 proof specification for our state tree (JMT). Our counterparties need this, we can use existing IAVL proof spec to verify our counterparty's proofs. - https://github.com/cosmos/ics23/pull/136
• [x] https://github.com/penumbra-zone/jmt/issues/18
• [x] Light client implementation for Penumbra, also light clients that can verify Cosmos SDK chains. We should get this automatically: our counterparties can run Tendermint light clients of Penumbra, and we can use tendermint light clients (such as tendermint-rs) to track our counterparties state.
• [x] #464: A way to include IBC packets in Penumbra transactions, so that relayers can add messages to the chain.
• [x] #465: A way for relayers to actually create those transactions.

Implementing the core IBC protocol in Penumbra's state machine

• [x] #466
• [x] #506
  • [x] #635
  • [x] #636
• [x] #637
• [x] #638
• [x] #639

After implementing the core IBC protocol (connections, channels, and packets), we can then

• [x] https://github.com/penumbra-zone/penumbra/issues/2859
• [x] #467
  • [x] #981
  • [x] #2284
  • [ ] https://github.com/penumbra-zone/penumbra/issues/2985
• [x] Implement client-side support for ICS20 withdrawals - https://github.com/penumbra-zone/penumbra/pull/2301
• [x] #3193
• [x] https://github.com/penumbra-zone/penumbra/issues/2173

Testing integrations, developer experience improvements

• [x] https://github.com/penumbra-zone/penumbra/issues/3222
• [x] https://github.com/penumbra-zone/penumbra/issues/3193
• [x] https://github.com/penumbra-zone/penumbra/issues/3116
• [x] https://github.com/penumbra-zone/penumbra/issues/3209
• [x] https://github.com/penumbra-zone/penumbra/issues/3045
• [ ] https://github.com/strangelove-ventures/interchaintest/issues/644
• [ ] https://github.com/strangelove-ventures/interchaintest/issues/313
• [ ] https://github.com/penumbra-zone/penumbra/issues/1813
• [ ] #2914
• [ ] https://github.com/penumbra-zone/penumbra/issues/3125

Stretch goals, non-blocking for mainnet, but tracking because completing these would make us friendly FOSS maintainers:

• [ ] Commit the JMT proof spec to cosmos/ics23 repo
• [ ] Add test vectors to cosmos/ics23 repo

Many IBC primitives (such as the protos for connections, channels, packets, etc) are already implemented in ibc-rs.

[conorsch]

This tracking issue has been around for nearly 2y now, and although it's been updated frequently, we need a fresh look at the state of play for IBC. Let's close it. @avahowell and I will work to respecify with work in light of recent experiences.

[hdevalence]

Closing as requested.