# Security Policy

## Destructive Operation Warning

**This tool performs irreversible destructive operations.**

Running `wipe` will permanently destroy all data on the target block device. This operation cannot be undone.

- Always verify the target device path (`lsblk`, `fdisk -l`) before running.
- Use `--dry-run` to preview what will happen without modifying data.
- The tool requires `--whole-disk` for whole-disk devices to prevent accidental wipes.
- Running system devices (`/`, `/boot`, `/boot/efi`, swap) are protected and will be refused even with `--yes` or `--force`.

## Logical Overwrite Limitations

Logical overwrite (zero, random, etc.) does **not** guarantee physical NAND erasure:

- Remapped sectors, SSD NAND cells, controller cache, and firmware-level storage may retain previous data.
- For SSDs/NVMe, prefer controller-level sanitize when supported:

  ```bash
  sudo wipe /dev/nvme0n1 --whole-disk --method nvme-sanitize
  sudo wipe /dev/nvme0n1 --whole-disk --method nvme-crypto  # if OPAL/crypto supported
  sudo wipe /dev/sda --whole-disk --method secure-discard   # for SATA SSD with secure discard
  ```

- Multiple overwrite passes do not necessarily improve erasure on flash media; controller-level operations are semantically different.

> **Logical read-back verification (`--verify` / `OVERWRITE_VERIFIED`) ≠ forensic proof of irrecoverability.**

Verification confirms that the logical LBA range reads back as written, but cannot prove that all physical media, spare areas, or controller caches have been erased.

## Reporting Vulnerabilities

If you discover a safety bypass or security issue (e.g., system disk protection can be bypassed, or the tool wipes an unintended device):

1. Do not publicly disclose immediately.
2. Open a security advisory via GitHub or contact the maintainer.
3. Provide steps to reproduce, device layout, and expected vs actual behavior.

## Safe Usage Checklist

- [ ] Confirmed device path with `lsblk --json` and `/dev/disk/by-id/`
- [ ] Ran with `--dry-run` first
- [ ] Verified device is not holding the running system
- [ ] Unmounted or used `--unmount` for filesystems
- [ ] Understood method semantics for your media type (HDD vs SSD vs NVMe)