Make send_packet method as private

[dhruvja]

Bug Summary

The send_packet method is public which can be used to send packets without token transfers. But using send_packet, a transfer packet can be spoofed without locking the tokens. So essentially, users can just call send_packet and get tokens on destination without token transfer on source.

Details

The send_packet method here should prolly be private or be removed once we have port management which will enable us to just use send_transfer with different port for cross chain messaging.

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

Line 20 in dcf8c36

pub fn send_packet(

Version

0.50.0

[rnbguy]

Thanks for the report! Currently, ibc-rs is vulnerable to permissionless calls to send_packet_validate.

This requires port management to fix this completely. We need to include port capability check in send_packet_validate and as well as send_packet_execute method.

[rnbguy]

Adding more context. We will probably need #465 and make sure, *_packet_execute cannot be called without *_packet_validate called before.

We will most likely need a way to create ValidatedContext after *_packet_validate. *_packet_validate should only be called on ValidatedContext. Need design decision for this.