---
title: ChainHook enum | Wartiva GraphQL API
description: ChainHook defines the network stack hook point where a base chain is attached. Wartiva GraphQL API reference with arguments, fields, and examples.
url: https://wartiva.com/api-docs/types/chain-hook.html
updated: 2026-10-07
---

Endpoint configuration · GraphQL enum

# `ChainHook` enum

ChainHook defines the network stack hook point where a base chain is attached. When a packet reaches a specific hook point, all chains associated with that hook are evaluated.

## Values

| Enum Value | Description |
|---|---|
| `PREROUTING` | Hook for incoming packets, before any routing decisions. |
| `INPUT` | Hook for packets destined for the local system. |
| `FORWARD` | Hook for packets being forwarded through the local system. |
| `OUTPUT` | Hook for locally generated outgoing packets. |
| `POSTROUTING` | Hook for outgoing packets, after routing decisions. |
| `UNSPECIFIED` | Hook is not specified or unknown. |

## Used by

- [`Chain`](https://wartiva.com/api-docs/types/chain.html) type: Represents an nftables chain, which is a named list of rules that are executed in order.

## Example

### Example

```json
"PREROUTING"

```

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