How to Prevent Signature Replay in Solana with Ed25519 Native Programs
When using the Ed25519 native program in Solana to verify a message signature, it is essential to implement measures to prevent replay attacks. A common technique is to add a preinstruction containing the signature, the message, and the sender’s public key. In this article, we will explore how to achieve this security feature in your custom program.
Why Prevent Signature Replay?
Signature replay attacks occur when an attacker intercepts and reuses a previously verified signature. This can be devastating for Solana-based systems, as it allows attackers to impersonate legitimate users and execute malicious transactions without consequences.
Implementing Ed25519 Native Programs in Solana
To prevent signature replay, we will use the Solana-program library, which provides an implementation of native programs on the Solana blockchain. We will focus on creating a preinstruction that contains the signature, message, and public key of the sender.
Here is an example of how to create a preinstruction using TypeScript:
import { Program } from '@solana-program/spl-program';
import { solanaProgram } from '../src';
const programId = 'your_program_id'; // Replace with your program ID
class SignatureReplayPreInstruction extends Program {
async getProgramData(programId: string): Promise {
const signature = 'your_signature_here'; // Replace with the actual signature
const message = 'your_message_here'; // Replace with the actual message
const publicKey = 'your_public_key_here'; // Replace with the actual public key
return JSON. stringify({
signature,
message,
publicKey,
});
}
asyncexecute(programId: string, data: string): Promise {
if (data. startsWith('pre_instruction')) {
const preInstruction = JSON. parse(data. substring(9));
console. log(Pre-instruction received with signature ${preInstruction.signature}, message ${preInstruction.message}, and public key ${preInstruction.publicKey});
}
}
}
// Initialize the program
const program = new solanaProgram(programId, SignatureReplayPreInstruction);
In this example, we define a SignatureReplayPreInstruction class that extends the Program class. The getProgramData method returns a string containing the sender’s signature, message, and public key.
The execute method checks if the received data starts with ‘pre_instruction’. If so, it parses the data as JSON and logs the contents to the console.
Using preinstruction in Ed25519 native programs
To use preinstruction in an Ed25519 native program, you will need to modify the nativeScript function to extract the signature, message, and public key from the received data. Here is an example of how to do this:
“`typescript
import { Program } from ‘@solana-program/spl-program’;
import { ed25519NativeScript } from ‘../src’;
const programId = ‘your_program_id’; // Replace with your program ID
class SignatureReplayPreInstruction extends Program {
async getProgramData(programId: string): Promise
const signature = ‘your_signature_here’; // Replace with actual signature
const message = ‘your_message_here’; // Replace with the actual message
const publicKey = ‘your_public_key_here’; // Replace with the actual public key
return JSON.stringify({
signature,
messages,
publicKey,
});
}
asyncexecute(programId: string, data: string): Promise
if (data.startsWith(‘pre_instruction’)) {
const preInstructionData = data.substring(9);
const [signature, message, publicKey] = preInstructionData.split(‘,’);
console.
