p2p: migrate secret_connection from tmkms

Closes informalsystems#691

Cargo.toml

@@ -3,6 +3,7 @@
 members = [
     "light-client",
     "light-node",
+    "p2p",
     "proto",
     "rpc",
     "rpc-probe",

p2p/Cargo.toml

@@ -0,0 +1,33 @@
+[package]
+name       = "p2p"
+version    = "0.1.0"
+edition    = "2018"
+license    = "Apache-2.0"
+repository = "https://github.com/informalsystems/tendermint-rs"
+readme     = "README.md"
+keywords   = ["p2p", "tendermint", "cosmos"]
+authors    = [
+  "Tony Arcieri <tony@iqlusion.io>",
+  "Ismail Khoffi <Ismail.Khoffi@gmail.com>"
+]
+
+description = """
+    The Tendermint P2P stack.
+    """
+
+[dependencies]
+chacha20poly1305 = "0.7"
+ed25519-dalek = "1"
+eyre = "0.6"
+hkdf = "0.10.0"
+merlin = "2"
+prost = "0.6"
+rand_core = { version = "0.5", features = ["std"] }
+sha2 = "0.9"
+subtle = "2"
+subtle-encoding = { version = "0.5", features = ["bech32-preview"] }
+tendermint = { version = "=0.17.0-rc3", features = ["secp256k1"] }
+tendermint-proto = "=0.17.0-rc3"
+thiserror = "1"
+x25519-dalek = "1.1"
+zeroize = "1"

p2p/src/error.rs

@@ -0,0 +1,20 @@
+//! Error types
+
+pub use eyre::{Report, Result};
+use thiserror::Error;
+
+/// Kinds of errors
+#[derive(Copy, Clone, Debug, Error, Eq, PartialEq)]
+pub enum Error {
+    /// Cryptographic operation failed
+    #[error("cryptographic error")]
+    CryptoError,
+
+    /// Malformatted or otherwise invalid cryptographic key
+    #[error("invalid key")]
+    InvalidKey,
+
+    /// Network protocol-related errors
+    #[error("protocol error")]
+    ProtocolError,
+}

p2p/src/lib.rs

@@ -0,0 +1,24 @@
+//! p2p
+//!
+//! The Tendermint P2P stack.
+
+// Tip: Deny warnings with `RUSTFLAGS="-D warnings"` environment variable in CI
+
+#![forbid(unsafe_code)]
+#![deny(
+    warnings,
+    missing_docs,
+    trivial_casts,
+    trivial_numeric_casts,
+    unused_import_braces,
+    unused_qualifications,
+    rust_2018_idioms,
+    nonstandard_style
+)]
+#![doc(
+    html_root_url = "https://docs.rs/tendermint-p2p/0.1.0",
+    html_logo_url = "https://raw.githubusercontent.com/informalsystems/tendermint-rs/master/img/logo-tendermint-rs_3961x4001.png"
+)]
+
+pub mod error;
+pub mod secret_connection;