About Blockchain Authenticator Contract

Provide a simple smart contract written in Rust to store a list of String.
This contract is used by the Blockchain Authenticator App to store the secret keys needed to generate the OTP password.

The contract must be called with 3 parameters :

• named-key : Name of the property where the data is stored
• method :
  • add : Add the "keys" to the current list of string
  • del : Remove the "keys" from the current list of string
  • dellall : Remove all elements from the list of string
• keys : List of strings

How to install

First, be sure that you have the needed tools installed.

You can check the Casper's documentation here

Here are the version of the tools that we've used to build and run the smartcontract :

rustup --version
rustup 1.24.3 (ce5817a94 2021-05-31)

cmake --version
cmake version 3.22.1

You also need Git to clone the repository.

To build the smartcontract :

git clone git@github.com:caspercommunityio/blockchain-authenticator-contract.git
cd blockchain-authenticator-contract
make prepare
make build-contract

How to run the tests

Follow the "how to install" part and then :

cd blockchain-authenticator-contract
make test

The output should be something like this :

make test
cd contract && cargo build --release --target wasm32-unknown-unknown
    Finished release [optimized] target(s) in 0.03s
wasm-strip contract/target/wasm32-unknown-unknown/release/contract.wasm 2>/dev/null | true
mkdir -p tests/wasm
cp contract/target/wasm32-unknown-unknown/release/contract.wasm tests/wasm
cd tests && cargo test
    Finished test [unoptimized + debuginfo] target(s) in 0.06s
     Running unittests (target/debug/deps/integration_tests-5924344271c8fdee)

running 8 tests
test tests::should_create_named_keys ... ok
test tests::should_panic_missing_parameters - should panic ... ok
test tests::should_add_multiple_elements ... ok
test tests::should_add_non_existing_element ... ok
test tests::should_not_del_element_non_existing_element ... ok
test tests::should_del_element ... ok
test tests::should_del_multiple_elements ... ok
test tests::should_update_existing_element ... ok

test result: ok. 8 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.28s

How to test on testnet

Install the "casper-client" using cargo :

cargo +nightly-2022-02-03 install casper-client --locked

Check that the "casper-client" is correctly installed :

casper-client --version
Casper client 1.5.0

Create a new account with Casper Signer and claim tokens using the faucet on https://testnet.cspr.live.

Then download your .pem file using the casper signer.

To deploy it on testnet, we have to use the following command :

casper-client put-deploy --chain-name casper-test -n http://95.216.67.162:7777 -k /path/to/your/secret/keys/private.pem -p 1000000000 -s /path/to/your/project/contract/target/wasm32-unknown-unknown/release/contract.wasm --session-args-complex /path/to/your/args.txt

As you can see, we use a file to store the args because the type CLList is considered complex.

The content of the file should be like this :

[
 {
	"name" : "method",
	"value" : {
		"raw_bytes" : "07000000030000006164640a"
	}
 },{
	"name" : "keys",
	"value" : {
		"raw_bytes" : "1100000001000000090000004944313b56414c55450e0a"
	}
 },{
	"name" : "named-key",
	"value" : {
		"raw_bytes" : "0800000004000000746573740a"
	}
 }
]

The values are encoded like specified in the Casper's documentation : https://docs.casperlabs.io/design/serialization-standard/#clvalue-clvalue

Here are some raw_bytes values for the parameters :

String "test" for the named-key parameter => 0800000004000000746573740a
String "add" => 07000000030000006164640a
String "del" => 070000000300000064656c0a
List of 1 Element "ID1;VALUE" => 1100000001000000090000004944313b56414c55450e0a
List of 2 Elements "ID1;VALUE, ID2;VALUE" => 1e00000002000000090000004944313b56414c5545090000004944323b56414c55450e0a
List of 3 Elements "ID1;VALUE, ID2;VALUE, ID3;VALUE" => 2b00000003000000090000004944313b56414c5545090000004944323b56414c5545090000004944333b56414c55450e0a

With these examples, you can try different tests scenarios on testnet.

The result of the deploy should be like this :

{
  "id": -6078809224594666102,
  "jsonrpc": "2.0",
  "result": {
    "api_version": "1.4.6",
    "deploy_hash": "c60402ece049fb41f60ae67bedeec4c0bd71b7fb0cec0d3267fd030eededa71e"
  }
}

You can check the result of the deploy on https://testnet.cspr.live.

How to write the contract for another blockchain

The smart contract must store an array of string with the following format "ID;VALUE". Then when you call the smartcontract, you must have at least 2 parameters :

• method :
  • add : Add the "keys" to the current list of string
  • del : Remove the "keys" from the current list of string
  • dellall : Remove all elements from the list of string
• keys : List of strings
• named-key (optional) : Name of the property where the data is stored

Then the webapp must be adapted to call and retrieve the data from that blockchain.

License

The Blockchain Authenticator Contract package is an open-sourced software licensed under the MIT license.