namei tips — authorized path-component literacy

Snapshot

Tip checklist (authorized only)

1. Confirm you may run namei on the lab host (syllabus box you own or were given access to).
2. Prefer documenting who / why / ticket before any deep path walk — never poke production without change control.
3. Record short factual notes; quote short Evidence (component type, owner, mode labels — never secrets or foreign home layouts).
4. Optional: ACL peer → getfacl-tips.
5. Optional: resolve peer → realpath-tips / readlink-tips.
6. Prefer disposable lab paths for namei drills; quote namei -l labpath afterward as Evidence.
7. Prefer -l / -m read-backs the syllabus authorizes — avoid inventing path-traversal cookbooks.
8. Stop at literacy — no attack or unauthorized path-enumeration cookbooks.

Allowed framing

• Classroom labs reviewing namei -l / namei -m on authorized disposable paths.
• Binding short factual notes as Evidence (component type/owner/mode — no secrets).
• Documenting expected vs observed path-component state for authorized inventory notes.
• Comparing namei ↔ getfacl / chmod / realpath / readlink peer tip pages under one binder.
• Testing symlink-follow behaviour only when the syllabus authorizes that drill on lab resources.

Scope we will not cover

• No crack/pirate/keygen via namei.
• No intentional unauthorized path walks against foreign hosts.
• No secret-theft or home-layout harvesting via path dumps on hosts you do not own.
• No cookbooks that abuse symlink races or weaken path checks without authorization.

Beginner path (authorized only)

1. Obtain one syllabus-approved disposable lab host with util-linux namei available.
2. Prefer a throwaway lab path tree before any deep walk.
3. With authorization, run namei -l labpath; quote non-secret component type/owner/mode labels as Evidence.
4. Optional: peer tip pages above when the syllabus asks.
5. Stop at literacy — no attack or unauthorized path-enumeration cookbooks.

Practical notes for authorized labs

• namei walks each path component — keep Evidence labels distinct from realpath-tips canonicalization.
• Pair with getfacl-tips when the syllabus zooms on ACL vs mode bits along a path.
• Path dumps may embed sensitive filenames — never paste secrets into notes or git.
• Prefer documenting component types and owner/mode labels the syllabus authorized without dumping full privileged inspect JSON.
• Never commit namei dumps with secrets to git — even for labs.

FAQ-aligned refusals (quick)

• Foreign-host path walks → refuse.
• Unauthorized symlink-race / path-bypass cookbooks → refuse.
• Attack/credential-theft framing → refuse.

For legal, authorized and educational use only.

FAQ

Sources