GitHub - yago-123/chainnet: Blockchain built from scratch

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Chainnet: distributed chain

Access live Chainnet metrics from the main seed node at dashboard.chainnet.yago.ninja/list.

Features

  • Decentralized peer-to-peer connectivity and synchronization
  • Node discovery via seed nodes and Kademlia DHT
  • Stack based RPN interpreter for payments
    • P2PK (Pay to Public Key)
    • P2PKH (Pay to Public Key Hash)
    • P2SH (Pay to Script Hash)
  • Block rewards for mining
  • Transaction fees
  • Wallets
    • ECDSA key generation
    • ECDSA signing
    • Hierarchical Deterministic (HD) Wallet
    • Mnemonic generation
  • Block and transaction validation
  • Block and transaction propagation
  • Mempool holding validated, unconfirmed transactions
  • UTXO set for tracking all unspent outputs and balances
  • Block conflict resolution during synchronization
  • Bloom filter for efficient lightweight client support

Configuration

Default configuration:

seed-nodes:                               # List of seed nodes
  - address: "seed-1.chainnet.yago.ninja"
    peer-id: "QmVQ8bj9KPfTiN23vX7sbqn4oXjTSycfULL4oApAZccWL5"
    port: 9100
#  ... more seed nodes ...

storage-file: "bin/miner-storage"         # File used for persisting the chain status
miner:
  pub-key-reward:                         # Public wallet key encoded in base58, used for receiving mining rewards
    "aSq9DsNNvGhYxYyqA9wd2eduEAZ5AXWgJTbTK2r1ViPYeJCMAcSHrt4AEkBouG5vmbAjKMGnZ1RyjP3bPTUhJrRXfEnD3CEhB7Rumao463ayeiU2jbRhjsygwqFp"
  mining-interval: "10m"                  # Interval between block creation
  adjustment-interval: 6                  # Number of blocks before adjusting the difficulty

chain:
  max-txs-mempool: 10000                  # Maximum number of transactions allowed in the mempool

prometheus:
  enabled: true                           # Enable or disable prometheus metrics
  port: 9091                              # Port exposed for prometheus metrics
  libp2p-port: 9099                       # Port exposed for prometheus core libp2p metrics
  path: "/metrics"                        # Path for prometheus metrics endpoint

p2p:
  enabled: true                           # Enable or disable network communication
  #identity-path: "identity.pem"          # ECDSA peer private key path in PEM format (leave empty to generate a random identity)
  peer-port: 9100                         # Port used for network communication with other peers
  http-api-port: 8080                     # Port exposed for the router API (required for nespv wallets)
  min-conn: 5                             # Minimum number of connections
  max-conn: 100                           # Maximum number of connections
  conn-timeout: "60s"                     # Maximum duration of a connection
  write-timeout: "20s"                    # Maximum duration of a write stream
  read-timeout: "20s"                     # Maximum duration of a read stream
  buffer-size: 4096                       # Read buffer size over the network

wallet:
  wallet-key-path: priv-key.pem           # ECDSA wallet private key path in PEM format
  server-address: "seed-1.chainnet.yago.ninja"
  server-port: 8080

Setup

Install dependencies:

$ sudo apt install protobuf-compiler base58

Install go packages:

$ go install google.golang.org/protobuf/cmd/protoc-gen-go
$ go install google.golang.org/grpc/cmd/protoc-gen-go-grpc

Increase UDP size to optimize P2P communication:

$ sudo sysctl -w net.core.rmem_max=7500000
$ sudo sysctl -w net.core.wmem_max=7500000

Building from source

Building the chainnet-nespv wallet:

Building the chainnet-node:

Building the chainnet-miner node:

Creating and Running Wallets

Step 1: Generate a Private Key

First, create a wallet by generating a private key with OpenSSL:

$ openssl ecparam -name prime256v1 -genkey -noout -out <wallet.pem>

This wallet.pem file will contain both the private and public keys.

IMPORTANT: this code is only compatible with prime256v1 elliptic curves (so far).

Step 2: Use the Wallet to Send Transactions

You can use this wallet by running the chainnet-nespv wallet to send transactions as follows:

$ ./bin/chainnet-nespv send            \
          --config default-config.yaml \
          --address random             \
          --amount 23.5 --fee 0.001    \
          --wallet-key-path <wallet.pem>

By default transactions use P2PK payments, if you want to use P2PKH payments you can use the --pay-type flag:

$ ./bin/chainnet-nespv send            \
          --config default-config.yaml \
          --address random             \
          --amount 23.5 --fee 0.001    \
          --pay-type P2PKH             \ 
          --wallet-key-path <wallet.pem>

You can use the addresses subcommand to list the addresses attached to this wallet:

$ ./bin/chainnet-nespv addresses \
           --wallet-key-path <wallet.pem>

Step 3: Extract the Public Key in Base58 Format

To receive rewards, you'll need to extract the public key from the wallet in base58 format. This can be done as follows:

$ openssl ec -in <wallet.pem> -pubout -outform DER 2>/dev/null | base58

Note: You can copy and paste the key obtained for using the wallet directly into the configuration file. The chain uses the encoded DER format for keys, as it remains unclear which signing algorithm will be used in the future.

Step 4: Configure the Miner for Rewards

Once you have the public key, paste it into the config.yaml file of the miner to receive mining rewards:

miner:
  pub-key-reward:                         # Public wallet key encoded in base58, used for receiving mining rewards
    "aSq9DsNNvGhYxYyqA9wd2eduEAZ5AXWgJTbTJVEyUnnaMDSRgUZKJzwFAdWKhSv8HTtbQbecee5xew2DPfqm467oef3KEW7bT54WdDWbvEqEhFv1YT3aPZZVqgKc"
  mining-interval: "10m"                  # Interval between block creation
  adjustment-interval: 6                  # Number of blocks before adjusting the difficulty

This ensures your mining rewards will be sent to the public key generated from your wallet.

Creating and running nodes and miners

Bare metal

Running the chainnet-node:

$ ./bin/chainnet-node --config default-config.yaml

Running the chainnet-miner:

$ ./bin/chainnet-miner --config default-config.yaml

Remote Nodes with Ansible

To run the chainnet-node on a remote node:

$ ansible-playbook -i ansible/inventories/seed/hosts.ini \
                   -e @ansible/config/node-seed.yml      \
                   ansible/playbooks/blockchain.yml

To run the chainnet-miner on a remote node:

$ ansible-playbook -i ansible/inventories/seed/hosts.ini \
                   -e @ansible/config/miner-seed.yml     \
                   ansible/playbooks/blockchain.yml

After the initial chain has been set up, you can also install logging and monitoring with default dashboards. To do this, you must first install Grafana:

$ ansible-playbook -i ansible/inventories/seed/hosts.ini \
                   ansible/playbooks/visualization.yml

Once Grafana is installed, you can configure your domain or access the Grafana instance via http://localhost:3000 and enter the new password (default credentials: admin/admin). If you need to install HTTPS certificates for the domain, you can run Certbot using the following playbook and then rerun the Grafana playbook to ensure the reverse proxy updates the HTTPS endpoint:

$ ansible-playbook -i ansible/inventories/seed/hosts.ini \
                   ansible/playbooks/install-SSL.yml
$ ansible-playbook -i ansible/inventories/seed/hosts.ini \
                   ansible/playbooks/visualization.yml

Once the chain is running and Grafana is up and accessible, you can install monitoring and/or logging via the following playbooks:

$ ansible-playbook -i ansible/inventories/seed/hosts.ini \
                   ansible/playbooks/monitoring.yml
$ ansible-playbook -i ansible/inventories/seed/hosts.ini \
                   ansible/playbooks/logging.yml

There is a set of default dashboards available to monitor the chain; however, it may take a few minutes for them to start loading real data.

Run in Docker (currently not mantained)

Running the chainnet-node:

$ mkdir /path/to/data
$ cp config/examples/docker-config.yaml /path/to/data/config.yaml
$ docker run -v ./path/to/data:/data           \
             -e CONFIG_FILE=/data/config.yaml  \
             -p 8080:8080                      \
             yagoninja/chainnet-node:latest

Running the chainnet-miner:

$ mkdir /path/to/data
$ cp config/examples/docker-config.yaml /path/to/data/config.yaml
$ docker run -v ./path/to/data:/data            \
             -e CONFIG_FILE=/data/config.yaml   \
             -p 8080:8080                       \
             yagoninja/chainnet-miner:latest

Run in Kubernetes (currently not mantained)

Deploy the helm chart:

$ helm install chainnet-release ./helm \
  --set-file configFile=config/examples/kubernetes-config.yaml

Uninstall the helm chart:

$ helm uninstall chainnet

Generating Node Identities

To authenticate nodes in P2P connections, you can generate a node identity. Start by generating an ECDSA secp256r1 private key in PEM format:

$ openssl ecparam -name prime256v1 -genkey -noout -out ecdsa-priv-key.pem

Next, reference the identity path in the configuration file:

p2p:
  enabled: true                           # Enable or disable network communication  
  identity-path: "ecdsa-priv-key.pem"     # Path to the ECDSA peer private key in PEM format (leave empty to generate a random identity)

Note that this identity can also be used to authenticate the seed nodes via the peer-id field:

seed-nodes:                               # List of seed nodes  
  - address: "seed-1.chainnet.yago.ninja"
    peer-id: "QmNXM4W7om3FdYDutuPjYCgTsazRNWhNn6fNyimf7SUHhR"
    port: 9100