ci(debug): probe raw DNS answers from the sandbox forwarder

commit: 9b651856f3edafe9b288efd7e3dd88d2e5a9a36c
author: brice · 33h ago · 2026-10-21 12:22 UTC
parent: 10fa005
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email
checks: 1/1

1 file · +51 -20

M .github/workflows/debug-dns.yml +51 -20


@@ -7,24 +7,55 @@ jobs:
7	7		dns:
8	8		runs-on: ubuntu-latest
9	9		steps:
10		-	- uses: actions/setup-node@949feb2413d6458794dcd2491c4babbbce0c15c1 # v7.1.0
11		-	with:
12		-	node-version: '24'
13	10		- run: \|
14		-	set -x
15		-	cat /etc/resolv.conf
16		-	cat /proc/sys/net/ipv6/conf/all/disable_ipv6 \|\| true
17		-	ip -6 addr \|\| true
18		-	getent ahostsv4 storage.googleapis.com \|\| true
19		-	getent ahostsv6 storage.googleapis.com \|\| true
20		-	getent ahostsv4 cdn.playwright.dev \|\| true
21		-	getent ahostsv6 cdn.playwright.dev \|\| true
22		-	node -e '
23		-	const dns=require("dns");
24		-	for (const h of ["cdn.playwright.dev","storage.googleapis.com"])
25		-	for (const family of [4,6])
26		-	dns.promises.lookup(h,{all:true,family}).then(
27		-	r=>console.log(h,family,"OK",JSON.stringify(r)),
28		-	e=>console.log(h,family,"ERR",e.code));
29		-	'
30		-	curl -4 -sS -o /dev/null -w '%{http_code} %{remote_ip}\n' -L --max-time 30 -r 0-1023 https://cdn.playwright.dev/builds/cft/156.0.8078.4/linux64/chrome-linux64.zip \|\| true
	11	+	cat > /tmp/probe.py <<'EOF'
	12	+	import random, socket, struct, time
	13	+
	14	+	NS = ("10.200.0.1", 53)
	15	+
	16	+	def query(name, qtype, edns):
	17	+	qid = random.randint(0, 65535)
	18	+	q = struct.pack(">HHHHHH", qid, 0x0100, 1, 0, 0, 1 if edns else 0)
	19	+	for label in name.split("."):
	20	+	q += bytes([len(label)]) + label.encode()
	21	+	q += b"\x00" + struct.pack(">HH", qtype, 1)
	22	+	if edns:
	23	+	q += b"\x00" + struct.pack(">HHIH", 41, edns, 0, 0)
	24	+	return q
	25	+
	26	+	def show(tag, r, t):
	27	+	flags, an = struct.unpack(">H", r[2:4])[0], struct.unpack(">H", r[6:8])[0]
	28	+	print(f"{tag}: {len(r)} bytes, rcode={flags & 0xF}, tc={(flags >> 9) & 1}, answers={an}, {t:.0f} ms")
	29	+
	30	+	def udp(name, qtype, edns):
	31	+	s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
	32	+	s.settimeout(4)
	33	+	t = time.time()
	34	+	s.sendto(query(name, qtype, edns), NS)
	35	+	try:
	36	+	show(f"udp {name} type={qtype} edns={edns}", s.recv(65535), (time.time() - t) * 1000)
	37	+	except Exception as e:
	38	+	print(f"udp {name} type={qtype} edns={edns}: {e!r}")
	39	+
	40	+	def tcp(name, qtype):
	41	+	q = query(name, qtype, 0)
	42	+	s = socket.create_connection(NS, timeout=4)
	43	+	t = time.time()
	44	+	s.sendall(struct.pack(">H", len(q)) + q)
	45	+	try:
	46	+	n = struct.unpack(">H", s.recv(2))[0]
	47	+	r = b""
	48	+	while len(r) < n:
	49	+	r += s.recv(n - len(r))
	50	+	show(f"tcp {name} type={qtype}", r, (time.time() - t) * 1000)
	51	+	except Exception as e:
	52	+	print(f"tcp {name} type={qtype}: {e!r}")
	53	+
	54	+	for name in ["storage.googleapis.com", "cdn.playwright.dev", "github.com"]:
	55	+	for qtype in (1, 28):
	56	+	for edns in (0, 1232):
	57	+	udp(name, qtype, edns)
	58	+	tcp(name, 1)
	59	+	EOF
	60	+	python3 /tmp/probe.py
	61	+	for i in 1 2 3; do getent ahostsv4 storage.googleapis.com \| head -1 \|\| echo "getent failed"; done


@@ -7,24 +7,55 @@ jobs:
7		dns:	7		dns:
8		runs-on: ubuntu-latest	8		runs-on: ubuntu-latest
9		steps:	9		steps:
10	-	- uses: actions/setup-node@949feb2413d6458794dcd2491c4babbbce0c15c1 # v7.1.0
11	-	with:
12	-	node-version: '24'
13		- run: \|	10		- run: \|
14	-	set -x	11	+	cat > /tmp/probe.py <<'EOF'
15	-	cat /etc/resolv.conf	12	+	import random, socket, struct, time
16	-	cat /proc/sys/net/ipv6/conf/all/disable_ipv6 \|\| true	13	+
17	-	ip -6 addr \|\| true	14	+	NS = ("10.200.0.1", 53)
18	-	getent ahostsv4 storage.googleapis.com \|\| true	15	+
19	-	getent ahostsv6 storage.googleapis.com \|\| true	16	+	def query(name, qtype, edns):
20	-	getent ahostsv4 cdn.playwright.dev \|\| true	17	+	qid = random.randint(0, 65535)
21	-	getent ahostsv6 cdn.playwright.dev \|\| true	18	+	q = struct.pack(">HHHHHH", qid, 0x0100, 1, 0, 0, 1 if edns else 0)
22	-	node -e '	19	+	for label in name.split("."):
23	-	const dns=require("dns");	20	+	q += bytes([len(label)]) + label.encode()
24	-	for (const h of ["cdn.playwright.dev","storage.googleapis.com"])	21	+	q += b"\x00" + struct.pack(">HH", qtype, 1)
25	-	for (const family of [4,6])	22	+	if edns:
26	-	dns.promises.lookup(h,{all:true,family}).then(	23	+	q += b"\x00" + struct.pack(">HHIH", 41, edns, 0, 0)
27	-	r=>console.log(h,family,"OK",JSON.stringify(r)),	24	+	return q
28	-	e=>console.log(h,family,"ERR",e.code));	25	+
29	-	'	26	+	def show(tag, r, t):
30	-	curl -4 -sS -o /dev/null -w '%{http_code} %{remote_ip}\n' -L --max-time 30 -r 0-1023 https://cdn.playwright.dev/builds/cft/156.0.8078.4/linux64/chrome-linux64.zip \|\| true	27	+	flags, an = struct.unpack(">H", r[2:4])[0], struct.unpack(">H", r[6:8])[0]
			28	+	print(f"{tag}: {len(r)} bytes, rcode={flags & 0xF}, tc={(flags >> 9) & 1}, answers={an}, {t:.0f} ms")
			29	+
			30	+	def udp(name, qtype, edns):
			31	+	s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
			32	+	s.settimeout(4)
			33	+	t = time.time()
			34	+	s.sendto(query(name, qtype, edns), NS)
			35	+	try:
			36	+	show(f"udp {name} type={qtype} edns={edns}", s.recv(65535), (time.time() - t) * 1000)
			37	+	except Exception as e:
			38	+	print(f"udp {name} type={qtype} edns={edns}: {e!r}")
			39	+
			40	+	def tcp(name, qtype):
			41	+	q = query(name, qtype, 0)
			42	+	s = socket.create_connection(NS, timeout=4)
			43	+	t = time.time()
			44	+	s.sendall(struct.pack(">H", len(q)) + q)
			45	+	try:
			46	+	n = struct.unpack(">H", s.recv(2))[0]
			47	+	r = b""
			48	+	while len(r) < n:
			49	+	r += s.recv(n - len(r))
			50	+	show(f"tcp {name} type={qtype}", r, (time.time() - t) * 1000)
			51	+	except Exception as e:
			52	+	print(f"tcp {name} type={qtype}: {e!r}")
			53	+
			54	+	for name in ["storage.googleapis.com", "cdn.playwright.dev", "github.com"]:
			55	+	for qtype in (1, 28):
			56	+	for edns in (0, 1232):
			57	+	udp(name, qtype, edns)
			58	+	tcp(name, 1)
			59	+	EOF
			60	+	python3 /tmp/probe.py
			61	+	for i in 1 2 3; do getent ahostsv4 storage.googleapis.com \| head -1 \|\| echo "getent failed"; done