Move name validation code to core

src/core/protocol/request_validation.rs

@@ -115,7 +115,7 @@ impl OwnerValidationError {
     }
 }
 
-#[derive(Error, Debug, PartialEq, Eq, Clone, Copy, Serialize, Deserialize)]
+#[derive(Error, Debug, PartialEq, Eq, Clone, Serialize, Deserialize)]
 pub enum AuthorizationError {
     #[error("Sanitization error: {0}")]
     SanitizationError(NameValidationError),
@@ -154,3 +154,126 @@ impl AuthorizationError {
         }
     }
 }
+
+const MAX_NAME_LENGTH: usize = 64;
+
+pub fn validate_name(name: &str) -> Result<(), NameValidationError> {
+    if name.is_empty() {
+        Err(NameValidationError::EmptyString)
+    } else if name.len() > MAX_NAME_LENGTH {
+        Err(NameValidationError::TooLong)
+    } else if !name
+        .chars()
+        .all(|c| c.is_ascii_alphanumeric() || c == '_' || c == '-')
+    {
+        Err(NameValidationError::InvalidCharacters)
+    } else {
+        Ok(())
+    }
+}
+
+pub fn validate_ownership_by_unix_user(
+    name: &str,
+    user: &UnixUser,
+) -> Result<(), OwnerValidationError> {
+    let prefixes = std::iter::once(user.username.to_owned())
+        .chain(user.groups.iter().cloned())
+        .collect::<Vec<String>>();
+
+    validate_ownership_by_prefixes(name, &prefixes)
+}
+
+/// Core logic for validating the ownership of a database name.
+/// This function checks if the given name matches any of the given prefixes.
+/// These prefixes will in most cases be the user's unix username and any
+/// unix groups the user is a member of.
+pub fn validate_ownership_by_prefixes(
+    name: &str,
+    prefixes: &[String],
+) -> Result<(), OwnerValidationError> {
+    if name.is_empty() {
+        return Err(OwnerValidationError::StringEmpty);
+    }
+
+    if prefixes
+        .iter()
+        .filter(|p| name.starts_with(&(p.to_string() + "_")))
+        .collect::<Vec<_>>()
+        .is_empty()
+    {
+        return Err(OwnerValidationError::NoMatch);
+    };
+
+    Ok(())
+}
+
+pub fn validate_db_or_user_request(
+    db_or_user: &DbOrUser,
+    unix_user: &UnixUser,
+) -> Result<(), AuthorizationError> {
+    validate_name(db_or_user.name()).map_err(AuthorizationError::SanitizationError)?;
+
+    validate_ownership_by_unix_user(db_or_user.name(), unix_user)
+        .map_err(AuthorizationError::OwnershipError)?;
+
+    Ok(())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_validate_name() {
+        assert_eq!(validate_name(""), Err(NameValidationError::EmptyString));
+        assert_eq!(validate_name("abcdefghijklmnopqrstuvwxyz"), Ok(()));
+        assert_eq!(validate_name("ABCDEFGHIJKLMNOPQRSTUVWXYZ"), Ok(()));
+        assert_eq!(validate_name("0123456789_-"), Ok(()));
+
+        for c in "\n\t\r !@#$%^&*()+=[]{}|;:,.<>?/".chars() {
+            assert_eq!(
+                validate_name(&c.to_string()),
+                Err(NameValidationError::InvalidCharacters)
+            );
+        }
+
+        assert_eq!(validate_name(&"a".repeat(MAX_NAME_LENGTH)), Ok(()));
+
+        assert_eq!(
+            validate_name(&"a".repeat(MAX_NAME_LENGTH + 1)),
+            Err(NameValidationError::TooLong)
+        );
+    }
+
+    #[test]
+    fn test_validate_owner_by_prefixes() {
+        let prefixes = vec!["user".to_string(), "group".to_string()];
+
+        assert_eq!(
+            validate_ownership_by_prefixes("", &prefixes),
+            Err(OwnerValidationError::StringEmpty)
+        );
+
+        assert_eq!(
+            validate_ownership_by_prefixes("user_testdb", &prefixes),
+            Ok(())
+        );
+        assert_eq!(
+            validate_ownership_by_prefixes("group_testdb", &prefixes),
+            Ok(())
+        );
+        assert_eq!(
+            validate_ownership_by_prefixes("group_test_db", &prefixes),
+            Ok(())
+        );
+        assert_eq!(
+            validate_ownership_by_prefixes("group_test-db", &prefixes),
+            Ok(())
+        );
+
+        assert_eq!(
+            validate_ownership_by_prefixes("nonexistent_testdb", &prefixes),
+            Err(OwnerValidationError::NoMatch)
+        );
+    }
+}