feat: generate and use private key from environment variable and add …

…support for dnsaddr seed peers (#27)

Description
---
In order to generate a private key earlier that can be used at any start
from env vars, we needed a solution.
Now there is a new cli option called `--generate-identity`. With this
option, you can generate a new identity (an encoded libp2p private key)
that can be used to set value later for `SHA_P2POOL_IDENTITY`
environment variable (the command outputs a json where `private_key`
field is the one need to use).
If that var is set, when starting p2pool with `--stable-peer` flag, it
will look for first for this env var and tries to decode and use it.
Also `/dnsaddr/*` seed peer addresses were not supported, now it is
supported, so p2pool will parse all the TXT DNS records and add them to
kademlia to bootstrap.

Motivation and Context
---

How Has This Been Tested?
---
```sh
cargo build --release
export SHA_P2POOL_IDENTITY=$(./target/release/sha_p2pool --generate-identity | jq -r '.private_key')
./target/release/sha_p2pool --stable-peer
```

After starting/stopping many times p2pool, the peer ID remains the same.

What process can a PR reviewer use to test or verify this change?
---
See testing.

Breaking Changes
---

- [x] None
- [ ] Requires data directory on base node to be deleted
- [ ] Requires hard fork
- [ ] Other - Please specify

Cargo.toml

@@ -47,6 +47,9 @@ log4rs = "1.3.0"
 axum = "0.7.5"
 itertools = "0.13.0"
 num = { version = "0.4.3", features = ["default", "num-bigint", "serde"] }
+hex = "0.4.3"
+serde_json = "1.0.122"
+hickory-resolver = { version = "*", features = ["dns-over-rustls"] }
 
 [package.metadata.cargo-machete]
 ignored = ["log4rs"]

src/main.rs

@@ -1,14 +1,18 @@
 // Copyright 2024 The Tari Project
 // SPDX-License-Identifier: BSD-3-Clause
 
+use std::env;
 use std::path::PathBuf;
 
 use clap::{
     builder::{styling::AnsiColor, Styles},
     Parser,
 };
+use libp2p::identity::Keypair;
+use tari_common::configuration::Network;
 use tari_common::initialize_logging;
 
+use crate::server::p2p;
 use crate::sharechain::in_memory::InMemoryShareChain;
 
 mod server;
@@ -48,9 +52,14 @@ struct Cli {
     /// (Optional) seed peers.
     /// Any amount of seed peers can be added to join a p2pool network.
     ///
-    /// Please note that these addresses must be in libp2p multi address format and must contain peer ID!
+    /// Please note that these addresses must be in libp2p multi address format and must contain peer ID
+    /// or use a dnsaddr multi address!
     ///
-    /// e.g.: /ip4/127.0.0.1/tcp/52313/p2p/12D3KooWCUNCvi7PBPymgsHx39JWErYdSoT3EFPrn3xoVff4CHFu
+    /// By default a Tari provided seed peer is added.
+    ///
+    /// e.g.:
+    /// /ip4/127.0.0.1/tcp/52313/p2p/12D3KooWCUNCvi7PBPymgsHx39JWErYdSoT3EFPrn3xoVff4CHFu
+    /// /dnsaddr/esme.p2pool.tari.com
     #[arg(short, long, value_name = "seed-peers")]
     seed_peers: Option<Vec<String>>,
 
@@ -91,6 +100,13 @@ struct Cli {
     /// If set, local stats HTTP server is disabled.
     #[arg(long, value_name = "stats-server-disabled", default_value_t = false)]
     stats_server_disabled: bool,
+
+    /// Generate identity
+    ///
+    /// If set, sha_p2pool will only generate a private key in `--private-key-folder`
+    /// and output a stable peer ID, that could be used later when running as a stable peer.
+    #[arg(long, value_name = "generate-identity", default_value_t = false)]
+    generate_identity: bool,
 }
 
 impl Cli {
@@ -105,6 +121,13 @@ impl Cli {
 async fn main() -> anyhow::Result<()> {
     let cli = Cli::parse();
 
+    // generate identity
+    if cli.generate_identity {
+        let result = p2p::util::generate_identity().await?;
+        print!("{}", serde_json::to_value(result)?);
+        return Ok(());
+    }
+
     // logger setup
     if let Err(e) = initialize_logging(
         &cli.base_dir().join("configs/logs.yml"),
@@ -122,11 +145,29 @@ async fn main() -> anyhow::Result<()> {
     if let Some(p2p_port) = cli.p2p_port {
         config_builder.with_p2p_port(p2p_port);
     }
-    if let Some(seed_peers) = cli.seed_peers.clone() {
-        config_builder.with_seed_peers(seed_peers);
+
+    // set default tari network specific seed peer address
+    let mut seed_peers = vec![];
+    let network = Network::get_current_or_user_setting_or_default();
+    if network != Network::LocalNet {
+        let default_seed_peer = format!("/dnsaddr/{}.p2pool.tari.com", network.as_key_str());
+        seed_peers.push(default_seed_peer);
     }
+    if let Some(cli_seed_peers) = cli.seed_peers.clone() {
+        seed_peers.extend(cli_seed_peers.iter().cloned());
+    }
+    config_builder.with_seed_peers(seed_peers);
+
     config_builder.with_stable_peer(cli.stable_peer);
     config_builder.with_private_key_folder(cli.private_key_folder.clone());
+
+    // try to extract env var based private key
+    if let Ok(identity_cbor) = env::var("SHA_P2POOL_IDENTITY") {
+        let identity_raw = hex::decode(identity_cbor.as_bytes())?;
+        let private_key = Keypair::from_protobuf_encoding(identity_raw.as_slice())?;
+        config_builder.with_private_key(Some(private_key));
+    }
+
     config_builder.with_mining_enabled(!cli.mining_disabled);
     config_builder.with_mdns_enabled(!cli.mdns_disabled);
     config_builder.with_stats_server_enabled(!cli.stats_server_disabled);

src/server/config.rs

@@ -3,6 +3,8 @@
 
 use std::{path::PathBuf, time::Duration};
 
+use libp2p::identity::Keypair;
+
 use crate::server::http::stats;
 use crate::server::{p2p, p2p::peer_store::PeerStoreConfig};
 
@@ -88,6 +90,11 @@ impl ConfigBuilder {
         self
     }
 
+    pub fn with_private_key(&mut self, config: Option<Keypair>) -> &mut Self {
+        self.config.p2p_service.private_key = config;
+        self
+    }
+
     pub fn with_mining_enabled(&mut self, config: bool) -> &mut Self {
         self.config.mining_enabled = config;
         self

src/server/p2p/error.rs

@@ -1,6 +1,8 @@
 // Copyright 2024 The Tari Project
 // SPDX-License-Identifier: BSD-3-Clause
 
+use std::string::FromUtf8Error;
+
 use libp2p::{
     gossipsub::PublishError, identity::DecodingError, kad::NoKnownPeers, multiaddr, noise, swarm::DialError,
     TransportError,
@@ -27,6 +29,8 @@ pub enum LibP2PError {
     Noise(#[from] noise::Error),
     #[error("Multi address parse error: {0}")]
     MultiAddrParse(#[from] multiaddr::Error),
+    #[error("Multi address empty")]
+    MultiAddrEmpty,
     #[error("Transport error: {0}")]
     Transport(#[from] TransportError<std::io::Error>),
     #[error("I/O error: {0}")]
@@ -43,4 +47,8 @@ pub enum LibP2PError {
     MissingPeerId(String),
     #[error("Key decode error: {0}")]
     KeyDecoding(#[from] DecodingError),
+    #[error("Invalid DNS entry: {0}")]
+    InvalidDnsEntry(String),
+    #[error("Failed to convert bytes to string: {0}")]
+    ConvertBytesToString(#[from] FromUtf8Error),
 }

src/server/p2p/mod.rs

@@ -13,3 +13,4 @@ mod error;
 pub mod messages;
 mod network;
 pub mod peer_store;
+pub mod util;