ssh-netbox-wrapper/README.md

# netssh

> **Vibe-coded project** — this codebase was written entirely by an AI assistant (Claude) without human code review. Use in production at your own risk.

A transparent SSH wrapper that resolves hostnames via [NetBox](https://netbox.dev/) before connecting.

Instead of looking up an IP manually, you just type the hostname as it appears in NetBox:

```sh
netssh my-router-01
netssh -p 2222 admin@app-server-03 uptime
```

`netssh` looks up the host in NetBox, resolves the right IP using a configurable strategy chain, and replaces the process with the native `ssh` binary — so all your existing SSH configs, keys, and agent forwarding work without any changes.

## Features

- **Transparent proxy** — replaces itself with `ssh` via `syscall.Exec`, preserving all SSH flags and options
- **Flexible IP resolution** — configurable chain of strategies: management subnet, primary IP, or named interface
- **Interactive TUI** — fuzzy search with live NetBox queries and 300 ms debouncing (start with `netssh`, no arguments)
- **Recently-used list** — TUI opens with your 10 most-recently-connected hosts, no typing needed
- **Tag/kind filter** — press `Ctrl+F` in the TUI to filter by `tag:prod` or `kind:vm`
- **User/port override** — press `e` in the TUI to override the SSH user or port before connecting
- **Persistent cache** — successful lookups are cached to `~/.cache/netssh/hosts.json` for instant shell completion
- **Full pagination** — `cache refresh` fetches all hosts from NetBox (not just the first 50)
- **Selective refresh** — `cache refresh --tag prod --kind vm` limits what gets synced
- **Setup wizard** — interactive first-run onboarding; re-run anytime with `netssh configure`
- **Shell completion** — install without sudo via `netssh completion install`
- **Default SSH user** — set a fallback username once in config instead of typing it every time
- **Default SSH port** — set a fallback port in config; injected as `-p` when not specified on the command line
- **Host shortcuts** — type `web01` instead of `web01.example.com`; configurable domain strip and hyphen folding
- **Shell aliases** — `netssh alias` generates shell aliases for all cached hosts
- **Automatic 24h cache refresh** — the cache is refreshed in the background every 24 hours

## Installation

### One-liner (Linux & macOS)

```sh
curl -fsSL https://git.zb-server.de/Sebi/ssh-netbox-wrapper/raw/branch/main/install.sh | bash
```

The script detects your OS and architecture, downloads the matching binary from the [latest release](https://git.zb-server.de/Sebi/ssh-netbox-wrapper/releases/latest), verifies the SHA-256 checksum, and installs to `/usr/local/bin/netssh` (using `sudo` only if necessary).

To install to a custom directory:

```sh
INSTALL_DIR=~/.local/bin curl -fsSL https://git.zb-server.de/Sebi/ssh-netbox-wrapper/raw/branch/main/install.sh | bash
```

### Build from source

```sh
git clone ssh://git@git.zb-server.de:30022/Sebi/ssh-netbox-wrapper.git
cd ssh-netbox-wrapper
go build -o netssh ./cmd/netssh
```

## Configuration

### Interactive wizard

On first run (when no config exists), `netssh` automatically starts an interactive setup wizard.
Re-run it at any time to change settings without editing the file manually:

```sh
netssh configure
```

The wizard walks through NetBox connection, SSH defaults, resolver strategies, and cache TTL,
then saves to `~/.config/netssh.yaml`.

### Manual config

`~/.config/netssh.yaml`:

```yaml
netbox:
  url: https://netbox.example.com
  token: nbt_your-api-token-here   # v2 token (nbt_ prefix) recommended
  token_version: 2                 # auto-detected from token; 1 = legacy, 2 = nbt_

resolver:
  # Strategies are tried in order; the first to return an IP wins.
  strategies:
    - management_subnet
    - primary_ip
  # Used by the management_subnet strategy.
  management_subnets:
    - 10.0.0.0/8
    - 172.16.0.0/12
  # Used by the interface_name strategy.
  interface_name: mgmt0

cache:
  ttl: 3600   # seconds; 0 = always query NetBox on connect (cache still used for completion)
  # path: ~/.cache/netssh/hosts.json  # default

ssh:
  default_user: admin  # used when no user is specified on the command line
  default_port: 2222   # optional; injected as -p if not specified on the command line

shortcuts:
  domains:             # strip these suffixes to create short aliases
    - .example.com
  strip_hyphens: false # if true, fsn1-web01 → fsn1web01 (cache-only resolution)
```

Any value can be overridden with environment variables (`NETSSH_NETBOX_URL`, `NETSSH_NETBOX_TOKEN`, etc.).

### API tokens

NetBox supports two token formats:

| Format | Example | Notes |
|--------|---------|-------|
| v2 (recommended) | `nbt_abc123…` | Create in NetBox → Admin → API Tokens |
| v1 (legacy) | `abc123def456…` | Older format; still works, but v2 is preferred |

`netssh` auto-detects the version from the token prefix and stores it as `token_version` in the config.
A hint is shown during `netssh configure` if a legacy v1 token is entered.

## Usage

### SSH wrapper mode

Pass any SSH flags and a NetBox hostname:

```sh
netssh my-router-01
netssh -p 2222 admin@app-server-03 uptime
netssh -i ~/.ssh/id_rsa -o StrictHostKeyChecking=no db-primary
```

The process is replaced by `ssh` with the resolved IP — your `~/.ssh/config`, agent, and keys all work as normal.

### Default username

Set `ssh.default_user` in the config to avoid typing a username every time:

```sh
netssh my-router        # → ssh -l admin 10.0.0.1
```

The default is only applied when no user is specified on the command line. An explicit user always takes precedence:

```sh
netssh root@my-router          # user@ prefix wins → ssh root@10.0.0.1
netssh -l ops my-router        # -l flag wins      → ssh -l ops 10.0.0.1
```

### Default SSH port

Set `ssh.default_port` in the config to use a non-standard port without specifying it every time:

```sh
netssh my-router        # → ssh -p 2222 -l admin 10.0.0.1
```

The default is only applied when `-p` is not already present in the SSH arguments. An explicit `-p` always takes precedence:

```sh
netssh -p 22 my-router  # -p flag wins → ssh -p 22 10.0.0.1
```

### Host shortcuts

Configure short aliases so you can type `web01` instead of `web01.example.com`:

```yaml
shortcuts:
  domains:
    - .example.com
    - .example.de
  strip_hyphens: false  # optional
```

Resolution order:

1. **Exact match** — the input is looked up as-is in the cache.
2. **Domain expansion** — if the input contains no dot, each configured domain is appended and tried (`web01` → `web01.example.com`). If no cache hit, NetBox is queried with the expanded name.
3. **Hyphen folding** (`strip_hyphens: true`) — hyphens are inserted back before looking up in the cache (`fsn1web01` → `fsn1-web01.example.com`). This only works when the host is already cached; run `netssh cache refresh` first.

| Input | Config | Resolved as |
|-------|--------|-------------|
| `web01` | `domains: [.example.com]` | `web01.example.com` |
| `fsn1web01` | `domains: [.example.com]`, `strip_hyphens: true` | `fsn1-web01.example.com` (cache only) |

### Shell aliases

Generate shell aliases for all cached hosts based on the shortcut settings:

```sh
netssh alias                  # bash/zsh syntax
netssh alias --shell fish     # fish syntax
```

Example output:

```bash
# netssh aliases (3 hosts) — source with: eval "$(netssh alias)"
alias db01='netssh db01.example.com'
alias fsn1web01='netssh fsn1-web01.example.com'
alias web01='netssh web01.example.com'
```

Add to your shell startup file:

```sh
# bash / zsh — in ~/.bashrc or ~/.zshrc
eval "$(netssh alias)"

# fish — in ~/.config/fish/config.fish
netssh alias --shell fish | source

# scripts
source <(netssh alias)
```

Without a `shortcuts` config, the alias name is derived from the full hostname with dots replaced by underscores (e.g. `web01_example_com`). If two hosts would produce the same alias name, the first entry wins and a warning is printed to stderr.

### Interactive TUI

Run without arguments to open the interactive search:

```sh
netssh
```

The TUI opens with your 10 most-recently-connected hosts. Start typing to search all cached hosts or query NetBox live.

| Key | Action |
|-----|--------|
| type | filter hosts (300 ms debounce → NetBox query) |
| `Tab` | autocomplete top result into the search field |
| `↑` / `↓` | navigate results |
| `Enter` | connect to selected host |
| `e` | open inline editor to override user/port before connecting |
| `Ctrl+F` | open/close tag and kind filter (`tag:prod kind:vm`) |
| `Esc` / `Ctrl+C` | quit (or close filter/edit if open) |

**Tag and kind filter** — press `Ctrl+F` to open a second input line:

```
Filter: tag:prod kind:vm
```

Multiple `tag:` values are AND-combined. The filter is applied locally against the cache; when doing a live NetBox search the first tag is also forwarded as a query parameter.

**User/port override** — press `e` on any highlighted host:

```
Connect as: admin@my-router:22
```

Edit the pre-filled value and press `Enter` to connect. `Esc` cancels. Port 22 is treated as default and omitted from the ssh command.

### Cache management

```sh
netssh cache list                         # show all cached entries
netssh cache refresh                      # re-fetch ALL hosts from NetBox (paginated)
netssh cache refresh --tag prod           # only hosts with the "prod" tag
netssh cache refresh --kind vm            # only virtual machines
netssh cache refresh --tag prod --kind vm # combine filters
netssh cache clear                        # wipe the cache
```

The cache is refreshed automatically in the background every 24 hours. The trigger fires on the next SSH connect or TUI start after the interval has elapsed — there is no delay to the connection itself. The timestamp of the last refresh is stored in `~/.cache/netssh/last_refresh`.

To also trigger the check at shell startup (before you run any SSH command), install the shell hook:

```sh
netssh hook install             # auto-detects $SHELL
netssh hook install --shell bash
netssh hook install --shell zsh
netssh hook install --shell fish
```

This appends a single line (`netssh shell-init`) to your shell profile. To remove it:

```sh
netssh hook uninstall
```

The hook is a no-op when the cache is fresh — it adds no measurable delay to your shell startup.

### Search (for scripting)

```sh
netssh search app-           # prints matching hostnames, one per line
```

## IP Resolution Strategies

Strategies are tried in the configured order; the first to succeed wins.

| Name | Description |
|------|-------------|
| `primary_ip` | Returns the `primary_ip4` (or `primary_ip6`) set in NetBox. No extra API call. |
| `management_subnet` | Fetches all IPs for the host and returns the first one matching a configured CIDR. |
| `interface_name` | Fetches IPs attached to a specific named interface (e.g. `mgmt0`). |

## Shell Completion

Install completion for the current user (no sudo required):

```sh
netssh completion install             # auto-detects $SHELL
netssh completion install --shell bash
netssh completion install --shell zsh
netssh completion install --shell fish
```

| Shell | Install path |
|-------|-------------|
| bash | `~/.local/share/bash-completion/completions/netssh` |
| zsh  | `~/.zfunc/_netssh` |
| fish | `~/.config/fish/completions/netssh.fish` |

For zsh, make sure `~/.zfunc` is in your `fpath` (add to `~/.zshrc`):

```zsh
fpath=(~/.zfunc $fpath)
autoload -Uz compinit && compinit
```

Completions are served from the local cache — no network request on every `<Tab>`.

## Shell Hook

`netssh hook install` sets up two things in your shell profile:

1. **`netssh shell-init`** — runs on every new shell session. It regenerates the alias file from the current cache so your aliases are always up to date, and starts a background cache refresh if the last full refresh was more than 24 hours ago.
2. **A `source` line** (bash/zsh only) — loads the generated alias file so shortcuts like `web01` work immediately in every new shell. Fish uses `conf.d/` auto-sourcing instead, so no explicit source line is needed.

The alias file is also generated immediately during `hook install`, so aliases are available as soon as you reload your profile — no `cache refresh` needed first (though the cache must not be empty).

### Install

```sh
netssh hook install             # auto-detects $SHELL
netssh hook install --shell bash
netssh hook install --shell zsh
netssh hook install --shell fish
```

Example output:

```
Hook installed → /home/user/.bashrc
Reload with: source /home/user/.bashrc
42 aliases written to /home/user/.cache/netssh/aliases.sh
```

What gets written to the profile:

**bash / zsh** (`~/.bashrc` or `~/.zshrc`):
```bash
netssh shell-init  # netssh cache auto-refresh
source ~/.cache/netssh/aliases.sh 2>/dev/null  # netssh aliases
```

**fish** (`~/.config/fish/config.fish`):
```fish
netssh shell-init  # netssh cache auto-refresh
```

Fish alias file (`~/.config/fish/conf.d/netssh.fish`) is written automatically and sourced by fish on every shell start without any profile changes.

| Shell | Profile file | Alias file |
|-------|-------------|------------|
| bash  | `~/.bashrc` | `~/.cache/netssh/aliases.sh` |
| zsh   | `~/.zshrc`  | `~/.cache/netssh/aliases.sh` |
| fish  | `~/.config/fish/config.fish` | `~/.config/fish/conf.d/netssh.fish` |

The install is idempotent — running it again changes nothing if the lines are already present.

Reload your profile after installation to activate immediately:

```sh
source ~/.bashrc    # bash
source ~/.zshrc     # zsh
source ~/.config/fish/config.fish  # fish
```

### Alias file updates

The alias file is regenerated automatically — no manual action needed:

| Event | Aliases updated |
|-------|----------------|
| New shell session (`shell-init`) | Yes — from the current local cache |
| `netssh cache refresh` | Yes — after the full refresh completes |
| Background 24h auto-refresh | Yes — after the background refresh completes |

Aliases for newly added hosts appear in the next shell session after a `cache refresh` has run.

### Uninstall

```sh
netssh hook uninstall             # auto-detects $SHELL
netssh hook uninstall --shell zsh
```

Removes both the `netssh shell-init` line and the `source aliases.sh` line from the profile. The alias files (`aliases.sh`, `netssh.fish`) are left on disk — delete them manually if desired.

### Relation to the connect-time auto-refresh

The shell hook and the connect-time trigger (which fires on each `netssh` invocation) are independent but complementary:

| Trigger | When it fires |
|---------|--------------|
| SSH connect / TUI start | On the next `netssh` call after 24 h have elapsed |
| Shell hook (`shell-init`) | On the first new shell session after 24 h have elapsed |

Both are non-blocking — the refresh runs as a background process and never delays your prompt or SSH connection. They share `~/.cache/netssh/last_refresh`, so only one background refresh runs per 24-hour window regardless of how many shells or connections are opened.

## Development

```sh
go test ./...        # run all tests
go build ./...       # build all packages
```

The test suite covers the cache, NetBox client (via `httptest`), IP resolver chain, SSH argument parser, config loading, setup wizard, shortcut normalization, and shell hook install/uninstall.

## Disclaimer

This is a **vibe-coded** project: the entire codebase — architecture, implementation, tests, and docs — was generated by an AI assistant (Claude by Anthropic). No human has reviewed or audited the code. It works for the author's personal use case, but correctness and security are not guaranteed. Read the source before running it in sensitive environments.

## How it works

1. `netssh` checks whether the first argument is a known subcommand (`configure`, `search`, `cache`, `completion`). If not, it enters SSH wrapper mode.
2. On first run or when `netbox.url` is empty, the interactive setup wizard starts automatically.
3. It parses the SSH arguments to extract the destination hostname, handling all flags that consume an extra argument (`-p`, `-i`, `-J`, …).
4. It resolves the destination: first an exact cache lookup, then shortcut expansion (domain append, hyphen folding) against the cache, and finally a fresh NetBox query with the expanded name. If the cache entry is within the TTL, no network request is made.
5. Otherwise it queries NetBox (`/api/dcim/devices/` and `/api/virtualization/virtual-machines/` in parallel), runs the result through the resolver chain, and caches the IP.
6. It calls `syscall.Exec` to replace itself with `ssh`, substituting the hostname with the resolved IP.