Sichere Caddy- und DNS-Stilllegung über Butler #29

Merged
sascha merged 2 commits from feat/safe-caddy-dns-removal-20260814 into main 2026-08-14 10:30:33 +02:00
2 changed files with 190 additions and 0 deletions

153
app.py
View file

@ -1458,6 +1458,159 @@ async def restore_iso_builder(dry_run: bool = Query(True), _=Depends(_verify)):
return result return result
CADDY_HOST = "root@46.225.230.72"
CADDYFILE_PATH = "/app-config/caddy/Caddyfile"
HETZNER_DNS_API = "https://api.hetzner.cloud/v1"
def _validate_managed_hostname(hostname: str) -> str:
hostname = hostname.strip().lower().rstrip(".")
if not re.fullmatch(r"[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?(?:\.[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?)+", hostname):
raise HTTPException(400, "Invalid hostname")
if not hostname.endswith(".sascha-lutz.de"):
raise HTTPException(400, "Hostname is outside the managed zone")
return hostname
def _caddy_site_remove_command(hostname: str, dry_run: bool) -> str:
script = '''import datetime, hashlib, json, os, re, subprocess, sys
path = %r
hostname = %r
dry_run = %r
def digest(data):
return hashlib.sha256(data.encode()).hexdigest()
def run(args):
p = subprocess.run(args, text=True, capture_output=True, timeout=30)
return {"rc": p.returncode, "stdout": p.stdout.strip()[-2000:], "stderr": p.stderr.strip()[-2000:]}
text = open(path, encoding="utf-8").read()
pattern = re.compile(r"(?m)^[ \\t]*" + re.escape(hostname) + r"[ \\t]*\\{")
match = pattern.search(text)
result = {"hostname": hostname, "dry_run": dry_run, "found": bool(match), "before_sha256": digest(text)}
if not match:
print(json.dumps(result)); raise SystemExit(0)
start = match.start(); depth = 0; end = None
for idx in range(match.end() - 1, len(text)):
if text[idx] == "{": depth += 1
elif text[idx] == "}":
depth -= 1
if depth == 0:
end = idx + 1
while end < len(text) and text[end] in " \\t": end += 1
while end < len(text) and text[end] == "\\n": end += 1
break
if end is None:
result["error"] = "Unbalanced Caddy site block"; print(json.dumps(result)); raise SystemExit(2)
result["line_start"] = text.count("\\n", 0, start) + 1
result["line_end"] = text.count("\\n", 0, end) + 1
if dry_run:
print(json.dumps(result)); raise SystemExit(0)
new = text[:start] + text[end:]
backup = path + ".pre-outline-removal-" + datetime.datetime.now().strftime("%%Y%%m%%d-%%H%%M%%S")
open(backup, "w", encoding="utf-8").write(text)
with open(path, "w", encoding="utf-8") as f:
f.write(new); f.flush(); os.fsync(f.fileno())
result["backup"] = backup
result["after_sha256"] = digest(new)
validation = run(["docker", "exec", "caddy", "caddy", "validate", "--config", "/etc/caddy/Caddyfile"])
result["validation"] = validation
if validation["rc"] != 0:
with open(path, "w", encoding="utf-8") as f:
f.write(text); f.flush(); os.fsync(f.fileno())
result["rolled_back"] = True; print(json.dumps(result)); raise SystemExit(3)
host_sha = run(["sha256sum", path])
container_sha = run(["docker", "exec", "caddy", "sha256sum", "/etc/caddy/Caddyfile"])
result["host_container_hash_match"] = bool(host_sha["stdout"] and container_sha["stdout"] and host_sha["stdout"].split()[0] == container_sha["stdout"].split()[0])
if not result["host_container_hash_match"]:
with open(path, "w", encoding="utf-8") as f:
f.write(text); f.flush(); os.fsync(f.fileno())
result["rolled_back"] = True; print(json.dumps(result)); raise SystemExit(4)
reload = run(["docker", "exec", "caddy", "caddy", "reload", "--config", "/etc/caddy/Caddyfile"])
result["reload"] = reload
if reload["rc"] != 0:
with open(path, "w", encoding="utf-8") as f:
f.write(text); f.flush(); os.fsync(f.fileno())
run(["docker", "exec", "caddy", "caddy", "reload", "--config", "/etc/caddy/Caddyfile"])
result["rolled_back"] = True; print(json.dumps(result)); raise SystemExit(5)
container_text = run(["docker", "exec", "caddy", "sh", "-c", "cat /etc/caddy/Caddyfile"])
result["hostname_absent"] = hostname not in container_text["stdout"]
print(json.dumps(result))
''' % (CADDYFILE_PATH, hostname, dry_run)
encoded = base64.b64encode(script.encode()).decode()
return f"python3 -c \"import base64;exec(base64.b64decode('{encoded}'))\""
@app.delete("/caddy/site/{hostname}")
async def caddy_site_remove(hostname: str, _=Depends(_verify), dry_run: bool = Query(True)):
hostname = _validate_managed_hostname(hostname)
rc, out, err = _ssh(CADDY_HOST, _caddy_site_remove_command(hostname, dry_run), timeout=90)
try:
result = json.loads(out)
except Exception:
raise HTTPException(502, (err or out or "Caddy removal returned no JSON")[-1000:])
if rc != 0:
raise HTTPException(502, result)
_audit(f"/caddy/site/{hostname}", "DELETE", 200, f"dry_run={dry_run}")
return result
async def _hetzner_zone_and_rrsets(zone_name: str):
token = _read("HETZNER_DNS_TOKEN")
if not token:
raise HTTPException(503, "HETZNER_DNS_TOKEN unavailable in Butler vault cache")
headers = {"Authorization": f"Bearer {token}"}
async with httpx.AsyncClient(timeout=30) as client:
zones_response = await client.get(f"{HETZNER_DNS_API}/zones", headers=headers, params={"name": zone_name})
if zones_response.status_code != 200:
raise HTTPException(502, f"Hetzner zones lookup failed: HTTP {zones_response.status_code}")
zones = zones_response.json().get("zones", [])
zone = next((item for item in zones if item.get("name") == zone_name), None)
if not zone:
raise HTTPException(404, "DNS zone not found")
rr_response = await client.get(f"{HETZNER_DNS_API}/zones/{zone['id']}/rrsets", headers=headers)
if rr_response.status_code != 200:
raise HTTPException(502, f"Hetzner RRSet lookup failed: HTTP {rr_response.status_code}")
return zone, rr_response.json().get("rrsets", []), headers
@app.get("/dns/rrset/{zone_name}/{record_name}")
async def dns_rrset_get(zone_name: str, record_name: str, _=Depends(_verify)):
zone_name = zone_name.strip().lower().rstrip(".")
hostname = _validate_managed_hostname(f"{record_name}.{zone_name}")
record_name = hostname[: -(len(zone_name) + 1)]
zone, rrsets, _headers = await _hetzner_zone_and_rrsets(zone_name)
selected = [r for r in rrsets if r.get("name") == record_name and r.get("type") in {"A", "AAAA", "CNAME"}]
return {"zone": zone_name, "zone_id": zone.get("id"), "name": record_name, "rrsets": selected}
@app.delete("/dns/rrset/{zone_name}/{record_name}")
async def dns_rrset_delete(zone_name: str, record_name: str, _=Depends(_verify), dry_run: bool = Query(True)):
zone_name = zone_name.strip().lower().rstrip(".")
hostname = _validate_managed_hostname(f"{record_name}.{zone_name}")
record_name = hostname[: -(len(zone_name) + 1)]
zone, rrsets, headers = await _hetzner_zone_and_rrsets(zone_name)
selected = [r for r in rrsets if r.get("name") == record_name and r.get("type") in {"A", "AAAA", "CNAME"}]
result = {"zone": zone_name, "zone_id": zone.get("id"), "name": record_name, "dry_run": dry_run, "rrsets": selected, "deleted": []}
if dry_run or not selected:
return result
async with httpx.AsyncClient(timeout=30) as client:
for rrset in selected:
url = f"{HETZNER_DNS_API}/zones/{zone['id']}/rrsets/{record_name}/{rrset['type']}"
response = await client.delete(url, headers=headers)
if response.status_code not in {200, 204}:
raise HTTPException(502, f"Hetzner RRSet delete failed for {rrset['type']}: HTTP {response.status_code}")
result["deleted"].append(rrset["type"])
verify_response = await client.get(f"{HETZNER_DNS_API}/zones/{zone['id']}/rrsets", headers=headers)
remaining = verify_response.json().get("rrsets", []) if verify_response.status_code == 200 else selected
result["remaining"] = [r for r in remaining if r.get("name") == record_name and r.get("type") in {"A", "AAAA", "CNAME"}]
if result["remaining"]:
raise HTTPException(502, "RRSet read-back still contains deleted record")
_audit(f"/dns/rrset/{zone_name}/{record_name}", "DELETE", 200, "deleted=" + ",".join(result["deleted"]))
return result
def _pve_auth(): def _pve_auth():
pv = _parse_kv("proxmox") pv = _parse_kv("proxmox")
return f"PVEAPIToken={pv.get('tokenid','')}={pv.get('secret','')}" return f"PVEAPIToken={pv.get('tokenid','')}={pv.get('secret','')}"

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@ -240,6 +240,43 @@ def test_iso_builder_restore_defaults_to_dry_run_and_has_no_free_target(monkeypa
assert "/app-config/ansible" in decoded assert "/app-config/ansible" in decoded
def test_caddy_site_remove_defaults_to_dry_run(monkeypatch):
payload = {"hostname": "wiki.sascha-lutz.de", "dry_run": True, "found": True, "line_start": 10, "line_end": 13}
calls = []
monkeypatch.setattr(app, "_ssh", lambda host, command, timeout=600: (calls.append((host, command, timeout)) or (0, __import__("json").dumps(payload), "")))
with TestClient(app.app) as client:
response = client.delete("/caddy/site/wiki.sascha-lutz.de", headers={"Authorization": "Bearer test-token"})
assert response.status_code == 200
assert response.json()["dry_run"] is True
assert calls[0][0] == app.CADDY_HOST
assert calls[0][2] == 90
def test_caddy_site_remove_rejects_unmanaged_hostname_before_ssh(monkeypatch):
monkeypatch.setattr(app, "_ssh", lambda *_args, **_kwargs: (_ for _ in ()).throw(AssertionError("must not SSH")))
with TestClient(app.app) as client:
response = client.delete("/caddy/site/example.com", headers={"Authorization": "Bearer test-token"})
assert response.status_code == 400
def test_dns_rrset_dry_run_returns_only_selected_records(monkeypatch):
async def fake_lookup(zone):
assert zone == "sascha-lutz.de"
return {"id": 96805, "name": zone}, [
{"name": "wiki", "type": "A", "records": [{"value": "46.225.230.72"}]},
{"name": "wiki", "type": "AAAA", "records": [{"value": "::1"}]},
{"name": "git", "type": "A", "records": [{"value": "46.225.230.72"}]},
], {"Authorization": "Bearer hidden"}
monkeypatch.setattr(app, "_hetzner_zone_and_rrsets", fake_lookup)
with TestClient(app.app) as client:
response = client.delete("/dns/rrset/sascha-lutz.de/wiki", headers={"Authorization": "Bearer test-token"})
assert response.status_code == 200
body = response.json()
assert body["dry_run"] is True
assert [item["type"] for item in body["rrsets"]] == ["A", "AAAA"]
assert body["deleted"] == []
def test_invalid_log_target_is_rejected_before_ssh(): def test_invalid_log_target_is_rejected_before_ssh():
with TestClient(app.app) as client: with TestClient(app.app) as client:
response = client.get( response = client.get(