[WIP] Encryption for secure values (#183)

src-tauri/yaak-crypto/src/workspace_key.rs

@@ -0,0 +1,116 @@
+use crate::encryption::{decrypt_data, encrypt_data};
+use crate::error::Error::InvalidHumanKey;
+use crate::error::Result;
+use base32::Alphabet;
+use chacha20poly1305::aead::{Key, KeyInit, OsRng};
+use chacha20poly1305::{KeySizeUser, XChaCha20Poly1305};
+
+#[derive(Debug, Clone)]
+pub struct WorkspaceKey {
+    key: Key<XChaCha20Poly1305>,
+}
+
+const HUMAN_PREFIX: &str = "YK";
+
+impl WorkspaceKey {
+    pub(crate) fn to_human(&self) -> Result<String> {
+        let encoded = base32::encode(Alphabet::Crockford {}, self.key.as_slice());
+        let with_prefix = format!("{HUMAN_PREFIX}{encoded}");
+        let with_separators = with_prefix
+            .chars()
+            .collect::<Vec<_>>()
+            .chunks(6)
+            .map(|chunk| chunk.iter().collect::<String>())
+            .collect::<Vec<_>>()
+            .join("-");
+        Ok(with_separators)
+    }
+
+    #[allow(dead_code)]
+    pub(crate) fn from_human(human_key: &str) -> Result<Self> {
+        let without_prefix = human_key.strip_prefix(HUMAN_PREFIX).unwrap_or(human_key);
+        let without_separators = without_prefix.replace("-", "");
+        let key =
+            base32::decode(Alphabet::Crockford {}, &without_separators).ok_or(InvalidHumanKey)?;
+        if key.len() != XChaCha20Poly1305::key_size() {
+            return Err(InvalidHumanKey);
+        }
+        Ok(Self::from_raw_key(key.as_slice()))
+    }
+
+    pub(crate) fn from_raw_key(key: &[u8]) -> Self {
+        Self {
+            key: Key::<XChaCha20Poly1305>::clone_from_slice(key),
+        }
+    }
+
+    pub(crate) fn raw_key(&self) -> &[u8] {
+        self.key.as_slice()
+    }
+
+    pub(crate) fn create() -> Result<Self> {
+        let key = XChaCha20Poly1305::generate_key(OsRng);
+        Ok(Self::from_raw_key(key.as_slice()))
+    }
+
+    pub(crate) fn encrypt(&self, data: &[u8]) -> Result<Vec<u8>> {
+        encrypt_data(data, &self.key)
+    }
+
+    pub(crate) fn decrypt(&self, data: &[u8]) -> Result<Vec<u8>> {
+        decrypt_data(data, &self.key)
+    }
+
+    #[cfg(test)]
+    pub(crate) fn test_key() -> Self {
+        Self::from_raw_key("f1a2d4b3c8e799af1456be3478a4c3f2".as_bytes())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::error::Error::InvalidHumanKey;
+    use crate::error::Result;
+    use crate::workspace_key::WorkspaceKey;
+
+    #[test]
+    fn test_persisted_key() -> Result<()> {
+        let key = WorkspaceKey::test_key();
+        let encrypted = key.encrypt("hello".as_bytes())?;
+        assert_eq!(key.decrypt(encrypted.as_slice())?, "hello".as_bytes());
+
+        Ok(())
+    }
+
+    #[test]
+    fn test_human_format() -> Result<()> {
+        let key = WorkspaceKey::test_key();
+
+        let encrypted = key.encrypt("hello".as_bytes())?;
+        assert_eq!(key.decrypt(encrypted.as_slice())?, "hello".as_bytes());
+
+        let human = key.to_human()?;
+        assert_eq!(human, "YKCRRP-2CK46H-H36RSR-CMVKJE-B1CRRK-8D9PC9-JK6D1Q-71GK8R-SKCRS0");
+        assert_eq!(
+            WorkspaceKey::from_human(&human)?.decrypt(encrypted.as_slice())?,
+            "hello".as_bytes()
+        );
+
+        Ok(())
+    }
+
+    #[test]
+    fn test_from_human_invalid() -> Result<()> {
+        assert!(matches!(
+            WorkspaceKey::from_human(
+                "YKCRRP-2CK46H-H36RSR-CMVKJE-B1CRRK-8D9PC9-JK6D1Q-71GK8R-SKCRS0-H3X38D",
+            ),
+            Err(InvalidHumanKey)
+        ));
+
+        assert!(matches!(WorkspaceKey::from_human("bad-key",), Err(InvalidHumanKey)));
+        assert!(matches!(WorkspaceKey::from_human("",), Err(InvalidHumanKey)));
+
+        Ok(())
+    }
+}