ap signing keys

cruciverb-server/src/activitypub/keys.rs

@@ -0,0 +1,51 @@
+use rsa::{RsaPrivateKey, RsaPublicKey};
+use rsa::pkcs1::{EncodeRsaPrivateKey, EncodeRsaPublicKey, DecodeRsaPrivateKey, DecodeRsaPublicKey, LineEnding};
+use rusqlite::Connection;
+
+pub struct ApKeys {
+    pub private_key: RsaPrivateKey,
+    pub public_key_pem: String,
+}
+
+pub fn load_or_generate(db: &Connection) -> ApKeys {
+    // try loading from DB
+    if let Ok((pub_pem, priv_pem)) = db.query_row(
+        "SELECT public_pem, private_pem FROM ap_keys WHERE id = 1",
+        [],
+        |row| Ok((row.get::<_, String>(0)?, row.get::<_, String>(1)?)),
+    ) {
+        let private_key = RsaPrivateKey::from_pkcs1_pem(&priv_pem)
+            .expect("failed to parse stored RSA private key");
+        let _ = RsaPublicKey::from_pkcs1_pem(&pub_pem)
+            .expect("failed to parse stored RSA public key");
+        return ApKeys {
+            private_key,
+            public_key_pem: pub_pem,
+        };
+    }
+
+    // generate new 2048-bit key pair
+    tracing::info!("generating RSA-2048 key pair for ActivityPub...");
+    let mut rng = rsa::rand_core::OsRng;
+    let private_key = RsaPrivateKey::new(&mut rng, 2048)
+        .expect("failed to generate RSA key");
+    let public_key = RsaPublicKey::from(&private_key);
+
+    let pub_pem = public_key.to_pkcs1_pem(LineEnding::LF)
+        .expect("failed to encode public key");
+    let priv_pem = private_key.to_pkcs1_pem(LineEnding::LF)
+        .expect("failed to encode private key");
+
+    let now = chrono::Utc::now().to_rfc3339();
+    db.execute(
+        "INSERT INTO ap_keys (id, public_pem, private_pem, created_at) VALUES (1, ?1, ?2, ?3)",
+        rusqlite::params![pub_pem, priv_pem.as_str(), now],
+    ).expect("failed to store RSA keys");
+
+    tracing::info!("RSA key pair generated and stored");
+
+    ApKeys {
+        private_key,
+        public_key_pem: pub_pem,
+    }
+}