Internet Computer Association

DFINITY Foundation

Synapse.vote (formerly ICP Maximalist Network)

Arthur’s Neuron (used to be cycle_dao)

ICDevs.org

CryptoIsGood

Anvil

ICPL.app

The Fools' Court

ysyms

The Accumulators’ Neuron

RawTech Venture

Paul Young

ICPMANUAL

8yeargangDAO

John Wiegley

Isaac Valadez

Krzysztof Żelazko

Always Rejects

Nicolas.ic

Smaug’s Neuron for Retail Investors

# Upgrade the Bitcoin Canister

## Changelog

### Changes

* Stability threshold is increased from 40 to 100.
* Fork resolution: rather than choosing the longest chain as the main chain,
  the difficulty of the blocks in each chain is now taken into account to
  protect against cases where an attacker manages to feed in a long fork that
  consists of blocks with low difficulty.

  You can read more about the difficulty-based approach here: https://wiki.internetcomputer.org/wiki/Bitcoin_integration#Fork_Resolution

## Commit Log

```text
> git log --format='%C(auto) %h %s' b1166..38b39cd

 38b39cd increase stability threshold to 100
 9242d5f Verify upgradability in CI (#137)
 9c3db9b test: add unit tests for stability count confirmations. (#138)
 1e91206 fix: make `sort -n` consistent across machines (#135)
 752fc86 chore(deps): bump tokio from 1.21.2 to 1.24.1 (#136)
 a936a1e chore: update profiling metrics (#134)
 44dfcdd chore: upgrade dfx to 0.12.1 (#132)
 d0f381d feat: use difficulty-based stability threshold for fork resolution (#126)
 bbf9875 fix: block header validation proptest (#133)
 56600d4 feat: compute block difficulty (#131)
```

## How can I verify the Wasm hash of this canister?

* Clone the [bitcoin-canister repo](https://github.com/dfinity/bitcoin-canister).
* `git checkout 38b39cd4a6aad5e5aae01d2a0fbe4e2ae06414fe`
* Run `docker build -t canisters .` to build the canisters and output their Wasm hashes.

You should then see the following in the output:

```
cd4603c63d7a817160a61eae446c2ba950f9fe2fd0ec1be5b2c9340687a692ab  ic-btc-canister.wasm.gz
```


Upgrade Nns Canister: ghsi2-tqaaa-aaaan-aaaca-cai to wasm with hash: cd4603c63d7a817160a61eae446c2ba950f9fe2fd0ec1be5b2c9340687a692ab