Here is an article on how to get the public key of a private key from Solana using Rust.
Getting a Private Key from Solana
When you create a transaction or sign a message in Solana, you need to provide both your public and private keys. The public key is used to broadcast transactions, while the private key is used to sign messages that can be verified by other nodes on the network.
While Solana provides a lot of information about its API, including functions for creating accounts, sending transactions, and more, there is no direct way to get the public key from a private key. However, we can achieve this using Rust.
Why do we need a public key
Before we dive into how to get the public key from a private key, let’s quickly review why it matters. In Solana, you need both a public and private key to:
- Broadcast transactions: Your public key is used to broadcast transactions to other nodes on the network.
- Sign messages: Your private key is used to sign messages that other nodes can verify.
Problems with Solana-specific features
Unfortunately, there is no direct functionality in the solana-sdk crate to get the public key from a private key. The API provided by solana-sdk focuses on creating and managing accounts, sending transactions, and signing messages, but it does not provide a built-in way to get the public key from a private key.
How to get a public key from a private key with Rust
Since we cannot use the native Solana features, we have to implement this functionality ourselves. One common approach is to generate a random key pair and then map the private key to its corresponding public key using the secp256k1 library.
Here is an example of how you can do this in your Rust code:
use std::fs;
use secp256k1::{EC,Key};
use solana_sdk::key::Ed25519Key;
use solana_sdk::prelude::*;
fn get_public_key_from_private_key(private_key: &[u8]) -> Result {;
let private_key = EC::decode(&private_key)?;
let public_key = private_key.public_key().to_bytes();
Ok ( public_key )
} }
fn main() -> Result<(), Ed25519KeyError> {
// Create a new secp256k1 key
let mut private_key = Key::new(Ed25519::from_raw_key_data(b"your_private_key_here"));
// Get the public key of the private key
let public_key = get_public_key_from_private_key(private_key.as_ref())?;
println!("Public key: {:?}", public_key);
ok (())
} }
This code generates a new secp256k1 key using the provided private key and then uses it to obtain the corresponding public key. Note that you should replace "your_private_key_here" with the actual data of your private key.
Conclusion
Although there is no direct function in the solana-sdk crate to get the public key from a private key, we have implemented this function ourselves using the secp256k1 type and Ed25519KeyError. This example shows how you can use Rust to get the public key of a private key from a 32-byte input.
Remember to always keep your private keys safe and never share them with anyone.
