Moving inner_tx from WrapperTx to Tx.

[murisi]

The objective is to (with as little change as possible) make Namada transactions signable on hardware constrained wallets by making them smaller. The approach to this taken in this branch is to replace inner transactions (amongst other objects) with their hashes, and then only attach the encrypted payloads at the top level.

More precisely, the following changes have been made:

• Replaced the transaction code field of Tx with a sum type that can either contain a hash or the literal code
• Removed the inner_tx field of WrapperTx leaving behind tx_hash
• Added an inner_tx field to Tx representing an attached encrypted inner transaction
• Added an inner_tx_code field to Tx representing an attached encrypted inner transaction code
• The ledger now decrypts and checks the attached inner_tx field against the Wrapper::tx_hash field
• The ledger now decrypts and checks the attached inner_tx_code field against the hash in the Tx::code field of the inner transaction

The implications of these changes are:

• Clients can now sign over either the full WASM code or a hash of it
• No encryption is required for/before the signing process (and hence on hardware wallets) because the signature for a WrapperTx is over the hash of an unencrypted Tx

[murisi]

pls update wasm

[murisi]

pls update wasm

[Fraccaman]

pls spawn devnet [anoma-devnet-0.13.0-zondax.toml,60,heliaxdev@1be9883,ON]

[Fraccaman]

pls spawn devnet [anoma-devnet-0.13.0-zondax.toml,60,heliaxdev@1be9883,ON]

[Fraccaman]

pls spawn devnet [anoma-devnet-0.13.0-zondax,60,heliaxdev@1be9883,ON]

[github-actions]

Devnet with chain id internal-devnet-2ba.40222721e7 spawned succesfully!

[Fraccaman]

pls spawn devnet [anoma-devnet-0.13.0-zondax,60,heliaxdev@1be9883,ON]

[github-actions]

Devnet with chain id internal-devnet-7c7.92696bafc8 spawned succesfully!

[Fraccaman]

pls spawn devnet [anoma-devnet-0.13.0-zondax,60,heliaxdev@1be9883,ON]

[github-actions]

Devnet with chain id internal-devnet-30a.875b15da08 spawned succesfully!

[tzemanovic]

@murisi would we still want to use this with the planned changes in #1255? I also see #1156, is that an alternative to this one?

[murisi]

@murisi would we still want to use this with the planned changes in #1255? I also see #1156, is that an alternative to this one?

Yes, that's the plan. I'm working on a branch that applies the proposal #1255 to this branch. If this idea works out, then this PR will be superseded/redundant. #1156 was the original approach to enabling hardware wallet signing and is now superseded/redundant. I've just closed it now.