FA-7016 / Proxy forwarding / Open access

Tunnel bytes bypass http transformation after upgrade · case 01

Tunnel bytes bypass http transformation after upgrade.

Verified by executionVariant 1 · 4 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The faulty implementation uses `transform+payload` for the tunnel-bytes-bypass-http-transformation-after-upgrade decision.

VERIFIED REPAIR

Apply the explicit tunnel-bytes-bypass-http-transformation-after-upgrade contract, including the tested boundary and negative cases.

Unsuccessful approach: The attempted repair uses `payload` and still violates a separate fixture.

Case contract

Bounded offline decision model: tunnel bytes bypass http transformation after upgrade. Inputs are already validated protocol fields; the explicit fixtures define the supported policy, not a complete protocol implementation.

Why this case matters

This deterministic proxy forwarding model isolates the tunnel-bytes-bypass-http-transformation-after-upgrade policy at a network component boundary.

1 / The failure

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(tunnel, payload, transform):
    return transform+payload
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve(True, 'abc', 'x'), 'abc')", "check('fixture 2', solve(False, 'abc', 'x'), 'xabc')", "check('fixture 3', solve(True, '', 'x'), '')", "check('fixture 4', solve(False, '', 'x'), 'x')"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
fixture 2	`xabc`	`xabc`	Passed
fixture 3	`x`		Failed
fixture 4	`x`	`x`	Passed
fixture 1	`xabc`	`abc`	Failed

SHA-256 / 600d65f65ecdd5f8ce9c5505e105afd4281fcdcc3e2f17cfd438494fa31b17b0

2 / The unsuccessful fix

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(tunnel, payload, transform):
    return payload
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve(True, 'abc', 'x'), 'abc')", "check('fixture 2', solve(False, 'abc', 'x'), 'xabc')", "check('fixture 3', solve(True, '', 'x'), '')", "check('fixture 4', solve(False, '', 'x'), 'x')"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
fixture 2	`abc`	`xabc`	Failed
fixture 3			Passed
fixture 4		`x`	Failed
fixture 1	`abc`	`abc`	Passed

SHA-256 / e2accf3d42beff6185c9d0a7c2315718a1ec9e7840090c3e58c986fdf18fd1e2

3 / The verified repair

Exit 0

"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(tunnel, payload, transform):
    return payload if tunnel else transform+payload
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve(True, 'abc', 'x'), 'abc')", "check('fixture 2', solve(False, 'abc', 'x'), 'xabc')", "check('fixture 3', solve(True, '', 'x'), '')", "check('fixture 4', solve(False, '', 'x'), 'x')"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
fixture 2	`xabc`	`xabc`	Passed
fixture 3			Passed
fixture 4	`x`	`x`	Passed
fixture 1	`abc`	`abc`	Passed

SHA-256 / 084629cb24f3add1f9236db2c14a435affc83ae9d9e9c64521488832a0643d2a

Verification & scope

Bounded deterministic policy model over validated inputs; not a complete protocol stack or an interoperability claim. The five variants rotate the same explicit fixture set. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:38:07.655078+00:00.

Case digest / adabd2e66ee1acd0134b37f68244b88d487802bedb9649eeb82bb9f08640d7fe