Identity transfers currently implemented in the following way:
There are an operation types IDENTITY_GIST_TRANSFER and IDENTITY_STATE_TRANSFER that have to be used fore
transferring state transitions from one chain to another.
An evm-identity-oracle-svc exists, that is responsible for delivering information from certain Iden3 state contract into the Rarimo chain.
After delivering information about state or GIST update, oracles (evm-identity-saver-svc) vote for information
correctness.
After successful voting, the threshold signature producers provides the ECDSA signature for state update information hash.
There is a modified state smart contracts that accepts state updates with ECDSA signature instead of ZK proof of state update validity.
Such smart contract should be deployed into every chain that we have to support.
The information about state update with its witness (ECDSA signature) can be delivered into modified state smart contracts on the target chain by everyone.
Also, the relayer service exists, that tracks new state and GIST update operations, their signatures and submits if requested transactions to the target chain. For the DApp it can be used in the following way:
To explore how the Iden3 protocol works please visit their documentation.
In the current implementation the identity saver subscribes to the certain EVM chain state smart contract and tracks
the StateLibStateUpdated events.
Event definition:
package main
import "math/big"
type StateLibStateUpdated struct {
Id *big.Int
BlockN *big.Int
Timestamp *big.Int
State *big.Int
Raw types.Log // Blockchain specific contextual infos
}
The following configuration .yaml file should be provided to launch your oracle:
log:
disable_sentry: true
level: debug
## Port to listen incoming requests (used to trigger revote for some operation - rare flow)
listener:
addr: :8000
evm:
## State contract for listening
contract_addr: ""
## Websocket address
rpc: ""
## Start block to listen events. (0 - listen from current). Used to catchup old events. Be careful to use.
start_from_block:
## According to network name in Rarimo core. Example: Polygon
network_name:
## How many blocks should be created after event to fetch it.
block_window:
broadcaster:
## address of broadcaster-svc
addr: ""
## sender account address (rarimo..)
sender_account: ""
## Rarimo chain connections
core:
addr: tcp://validator:26657
cosmos:
addr: validator:9090
## Profiling
profiler:
enabled: false
addr: :8080
## Issuer information
state_contract_cfg:
issuer_id: "issuer id in decimal format"
After fetching of some event, oracle will create the corresponding transaction and submit it to the Rarimo blockchain. After transaction appears in Rarimo blockchain all chain oracles have to vote for its correctness. So they will fetch the information about state update from Rarimo chain, verify it and submit their votes (YES/NO answers).
For submitting transactions, savers (oracles) uses the broadcaster-svc. It accepts the transaction by GRPC endpoint, signs it with configured private key and submits it to the Rarimo chain.
The following configuration .yaml file should be provided to launch your broadcaster service:
log:
disable_sentry: true
level: debug
## Port to listen incoming requests
listener:
addr: :80
## PostgreSQL database connect
db:
url: "postgres://broadcaster:broadcaster@broadcaster-db/broadcaster?sslmode=disable"
key:
## Rarimo account private key in Hex format: 0x123fab...
sender_prv_hex: ""
## Rarimo chain id
chain_id: "rarimo_201411-2"
## Base coin name
coin_name: "urmo"
cosmos:
addr: "validator:9090"
Explore the simple docker-compose file to run the described services:
version: "3.7"
services:
broadcaster:
image: ghcr.io/rarimo/broadcaster-svc:v1.0.2
restart: unless-stopped
depends_on:
- broadcaster-db
volumes:
- ./config/broadcaster.yaml:/config.yaml
environment:
- KV_VIPER_FILE=/config.yaml
entrypoint: sh -c "broadcaster-svc migrate up && broadcaster-svc run all"
broadcaster-db:
image: postgres:13
restart: unless-stopped
environment:
- POSTGRES_USER=broadcaster
- POSTGRES_PASSWORD=broadcaster
- POSTGRES_DB=broadcaster
- PGDATA=/pgdata
volumes:
- broadcaster-data:/pgdata
evm-identity-saver:
image: ghcr.io/rarimo/evm-identity-saver-svc:v1.0.6
restart: unless-stopped
depends_on:
- broadcaster
volumes:
- ./config/evm-saver.yaml:/config.yaml
environment:
- KV_VIPER_FILE=/config.yaml
entrypoint: sh -c "evm-identity-saver-svc run state-update-all"
Relayer service is responsible for fetching information from Rarimo chain about new signatures
for IDENTITY_GIST_TRANSFER and IDENTITY_STATE_TRANSFER operations.
The following configuration .yaml file should be provided to launch your raleyer service:
log:
disable_sentry: true
level: debug
# The port to run on
listener:
addr: :8000
# PostgreSQL DB connect
db:
url: "postgres://postgres:postgres@localhost:5432/postgres?sslmode=disable"
# Rarimo core RPCs
core:
addr: tcp://validator:26657
cosmos:
addr: validator:9090
evm:
chains:
- name: "Ethereum"
## Address of the modified state contract on target chain
contract_address: ""
## Private key HEX (without leading 0x) that will pay the tx fee
submitter_private_key: ""
## RPC address. Example https://mainnet.infura.io/v3/11111
rpc:
## Target chain id
chain_id: 1
relay:
# Flag the indicates should service iterate over all existing transfer operation and fill the database
catchup_disabled: true
Explore the simple docker-compose file to run described services:
version: "3.7"
services:
redis:
image: 'bitnami/redis:latest'
environment:
- ALLOW_EMPTY_PASSWORD=yes
relayer:
image: registry.gitlab.com/rarimo/polygonid/relayer-svc:v1.0.2
restart: on-failure
depends_on:
- redis
volumes:
- ./config/relayer.yaml:/config.yaml
environment:
- KV_VIPER_FILE=/config.yaml
entrypoint: sh -c "relayer-svc run all"
The issuer service required to be launched by your own to publish users’ claims.
Currently, running of your oracle service requires staking of RMO tokens in Rarimo chain.
Support of certain smart contract and issuer by oracles requires the voting between all active oracles for that chain. It means that for your chain all other oracles have to update their configuration to support your smart contract and issuer. Also, the chain-clone can be added to the Rarimo to split oracle groups.