From d296f40eae77ab6393c0b6499608e745098a2e8c Mon Sep 17 00:00:00 2001
From: Eli Ribble <eli@theribbles.org>
Date: Wed, 6 Dec 2023 21:16:02 -0700
Subject: [PATCH] Add signature validation.
I also realized I wasn't saving the public and private halves separately so
I'm doing that now too.
God, Rust is great and I'm learning it so slowly.
---
README.md | 3 ++-
gongor.rs | 50 +++++++++++++++++++++++++++++++++++++++++++-------
2 files changed, 45 insertions(+), 8 deletions(-)
diff --git a/README.md b/README.md
index d858cfe..b2ae10c 100644
--- a/README.md
+++ b/README.md
@@ -6,8 +6,9 @@ Anagram of "Gorgon".
## Actions
- * `cargo run -- create eli.key`: makes a new key.
+ * `cargo run -- create eli.key eli.publickey`: makes a new key.
* `cargo run -- sign eli.key message.txt [message.sig]`: signs a message, optionally writes the signature to a file.
+ * `cargo run -- validate eli.publickey message.txt message.signed`: validates a signature.
## TODO
diff --git a/gongor.rs b/gongor.rs
index 0e34fdd..b26625f 100644
--- a/gongor.rs
+++ b/gongor.rs
@@ -6,6 +6,10 @@ use rand::rngs::OsRng;
use ed25519_dalek::SigningKey;
use ed25519_dalek::Signature;
use ed25519_dalek::Signer;
+use ed25519_dalek::Verifier;
+use ed25519_dalek::VerifyingKey;
+use ed25519_dalek::{PUBLIC_KEY_LENGTH, SECRET_KEY_LENGTH, SIGNATURE_LENGTH};
+
fn main() -> std::io::Result<()>{
let action = std::env::args().nth(1).expect("no command given");
@@ -16,7 +20,7 @@ fn main() -> std::io::Result<()>{
let mut keyfile = File::open(&keyfilepath).expect("no file found");
- let mut keybuffer: [u8; 32] = [0; 32];
+ let mut keybuffer: [u8; 32] = [0; SECRET_KEY_LENGTH];
keyfile.read(&mut keybuffer).expect("buffer overflow");
let signing_key: SigningKey = SigningKey::from_bytes(&keybuffer);
@@ -38,18 +42,50 @@ fn main() -> std::io::Result<()>{
} else {
println!("Signture: {signature}");
}
- return Ok(())
+ } else if action == "validate" {
+ let public_key_filepath = std::env::args().nth(2).expect("no key filepath given");
+ let message_filepath = std::env::args().nth(3).expect("no message filepath given");
+ let signature_filepath = std::env::args().nth(4).expect("no signature filepath given");
+
+ let mut public_keyfile = File::open(&public_key_filepath).expect("no file found");
+ let mut public_keybuffer: [u8; PUBLIC_KEY_LENGTH] = [0; PUBLIC_KEY_LENGTH];
+ public_keyfile.read(&mut public_keybuffer).expect("buffer overflow");
+ let public_key: VerifyingKey = VerifyingKey::from_bytes(&public_keybuffer).expect("Faled to make a key");
+
+ let messagefile= File::open(&message_filepath).expect("no file found");
+ let mut messagereader = BufReader::new(messagefile);
+ let mut messagebuf = Vec::new();
+ messagereader.read_to_end(&mut messagebuf)?;
+
+ let signature_file = File::open(&signature_filepath).expect("no file found");
+ let mut signature_reader = BufReader::new(signature_file);
+ let mut signature_buf: [u8; SIGNATURE_LENGTH] = [0; SIGNATURE_LENGTH];
+ signature_reader.read(&mut signature_buf).expect("buffer overflow");
+ let signature: Signature = Signature::try_from(&signature_buf[..]).expect("not a signature");
+
+ if public_key.verify(&messagebuf, &signature).is_ok() {
+ println!("Yep, that checks out.");
+ } else {
+ println!("Invalid signature.");
+ }
} else if action == "create" {
- let keyfilepath = std::env::args().nth(2).expect("no keyfilepath given");
+ let signing_key_filepath = std::env::args().nth(2).expect("no signing key file path given");
+ let verifying_key_filepath = std::env::args().nth(3).expect("no verifying key file path given");
+
let mut csprng = OsRng;
let signing_key: SigningKey = SigningKey::generate(&mut csprng);
- println!("Writing new key to {keyfilepath}");
- let mut file = File::create(keyfilepath)?;
+ println!("Writing new private key to {signing_key_filepath}");
+ let mut file = File::create(signing_key_filepath)?;
file.write_all(&signing_key.to_bytes())?;
- return Ok(());
+
+ println!("Writing new public key to {verifying_key_filepath}");
+ let verifying_key: VerifyingKey = signing_key.verifying_key();
+ file = File::create(verifying_key_filepath)?;
+ file.write_all(&verifying_key.to_bytes())?;
+
} else {
println!("Unrecognized command {action}");
- return Ok(());
}
+ return Ok(());
}