zeroclaw-labs/zeroclaw · error

NAT64 prefix is empty

Error message

NAT64 prefix is empty

What it means

Error "NAT64 prefix is empty" thrown in zeroclaw-labs/zeroclaw.

Source

Thrown at crates/zeroclaw-infra/src/net_guard.rs:613

impl std::fmt::Display for Nat64Prefix {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(f, "{}/{}", self.network, self.len)
    }
}

impl Nat64Prefix {
    /// Parse one `<ipv6>/<len>` entry, for example `"2001:db8:122:344::/96"`.
    ///
    /// # Errors
    ///
    /// Returns an error describing the problem when the entry has no `/`, does
    /// not parse as an IPv6 address, uses a prefix length outside
    /// RFC 6052 §2.2's `/32`, `/40`, `/48`, `/56`, `/64`, `/96`, or sets any
    /// bit beyond the prefix length.
    pub fn parse(raw: &str) -> anyhow::Result<Self> {
        let entry = raw.trim();
        if entry.is_empty() {
            anyhow::bail!("NAT64 prefix is empty");
        }

        let (address, length) = entry
            .split_once('/')
            .ok_or_else(|| anyhow::Error::msg("missing '/<prefix-length>'"))?;

        let network = address
            .parse::<std::net::Ipv6Addr>()
            .map_err(|e| anyhow::Error::msg(format!("'{address}' is not an IPv6 address: {e}")))?;
        let len = length
            .parse::<u8>()
            .map_err(|e| anyhow::Error::msg(format!("'{length}' is not a prefix length: {e}")))?;

        if !RFC6052_PREFIX_LENGTHS.contains(&len) {
            anyhow::bail!(
                "prefix length /{len} is not one of the RFC 6052 lengths /32, /40, /48, /56, /64, /96"
            );
        }

View on GitHub (pinned to 88bb9c8533)

Solutions

1. Provide a non-empty NAT64 prefix, e.g. 64:ff9b::/96.

When it happens

Trigger: Thrown at crates/zeroclaw-infra/src/net_guard.rs:613 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of zeroclaw-labs/zeroclaw@88bb9c8533 (2026-08-23). Data as JSON: /api/errors/cde2861fd5cc80e5. Report an issue: GitHub.