feat: plan 16 P1 (SEC-08/09/19/20/21) — fail-open/DoS/authz hardening

- SEC-08 pii-mask: fail-closed on missing rules / broken regex (no unmasked leak) - SEC-09: input-size cap + fail-closed reads (security-check/drift-detect/context-compress); non-UTF8 no longer crashes - SEC-19: control-plane store POSIX flock + atomic tmp+rename write - SEC-20: new toolchain-verify.sh (missing/PATH-shadowed/in-workspace binary -> refuse); wired into harness-preflight - SEC-21: model-call timeout 180->60s configurable + per-run call budget - SEC-11 realized by SEC-17 prod profile (no code) - 5 fail-able test suites wired into ci-harness-gate.sh; test-integrity manifest regenerated Verify: SEC+integrity gate 16/0, run-casan4 0-FAIL, adversarial 44/44, no regressions. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-06 22:21:34 +09:00
parent 8c3c5e8bff
commit e70f0815ab
17 changed files with 611 additions and 62 deletions
@@ -0,0 +1,57 @@
+#!/usr/bin/env bash
+set -uo pipefail
+
+# CASAN Plan-16 SEC-20 (ARCH-04 / ARCH-09) — toolchain verification, fail-closed.
+#
+# Gate verdicts depend on external binaries. A missing tool (silent no-op) or a
+# PATH-shadowed fake (attacker-controlled verdict) must refuse, not run. Proves:
+#   * present toolchain passes,
+#   * a missing required tool fails,
+#   * a required tool planted INSIDE the workspace is rejected (shadow),
+#   * with a trusted-dir allowlist, a tool outside it is rejected,
+#   * harness-preflight fails closed when the toolchain check fails.
+#
+# Deterministic; hermetic; no model/network.
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_ROOT="$(cd "$SCRIPT_DIR/../.." && pwd)"
+BASH_DIR="$PROJECT_ROOT/.specify/scripts/bash"
+TV="$BASH_DIR/toolchain-verify.sh"
+WORK="$(mktemp -d)"
+trap 'rm -rf "$WORK"; rm -rf "$PROJECT_ROOT/.specify/_sec20probe"' EXIT
+
+PASS=0; FAIL=0
+pass() { echo "PASS: $1"; PASS=$((PASS + 1)); }
+fail() { echo "FAIL: $1"; FAIL=$((FAIL + 1)); }
+rc_of() { set +e; "$@" >/dev/null 2>&1; echo $?; set -e 2>/dev/null || true; }
+
+echo "===== Plan-16 SEC-20: toolchain verification fail-closed ====="
+
+[[ "$(rc_of bash "$TV")" -eq 0 ]] \
+  && pass "present toolchain passes" || fail "present toolchain rejected"
+
+[[ "$(rc_of bash "$TV" definitely_missing_tool_xyz)" -ne 0 ]] \
+  && pass "missing required tool → refuse (ARCH-09)" || fail "missing tool not refused"
+
+# Plant a fake required tool INSIDE the workspace, put it first on PATH.
+PROBE="$PROJECT_ROOT/.specify/_sec20probe"; mkdir -p "$PROBE"
+printf '#!/bin/sh\necho fake\n' > "$PROBE/awk"; chmod +x "$PROBE/awk"
+RC="$(set +e; PATH="$PROBE:$PATH" bash "$TV" awk >/dev/null 2>&1; echo $?)"
+[[ "$RC" -ne 0 ]] && pass "in-workspace planted binary → refuse (shadow, ARCH-04)" \
+  || fail "workspace-shadowed binary accepted"
+
+# Allowlist mode: a fake tool in a temp dir outside the trusted dirs is rejected.
+printf '#!/bin/sh\necho fake\n' > "$WORK/grep"; chmod +x "$WORK/grep"
+RC="$(set +e; PATH="$WORK:$PATH" CASAN_TOOLCHAIN_TRUSTED_DIRS="/usr/bin:/bin:/usr/local/bin:/opt/homebrew/bin" bash "$TV" grep >/dev/null 2>&1; echo $?)"
+[[ "$RC" -ne 0 ]] && pass "untrusted-dir binary rejected under allowlist" \
+  || fail "untrusted-dir binary accepted under allowlist"
+
+# harness-preflight fails closed when toolchain-verify fails (planted required tool).
+printf '#!/bin/sh\necho fake\n' > "$PROBE/openssl"; chmod +x "$PROBE/openssl"
+RC="$(set +e; PATH="$PROBE:$PATH" bash "$BASH_DIR/harness-preflight.sh" "$WORK/none" --model local >/dev/null 2>&1; echo $?)"
+[[ "$RC" -ne 0 ]] && pass "harness-preflight blocks on shadowed toolchain" \
+  || fail "preflight did not block on shadowed toolchain"
+
+echo ""
+echo "===== SEC-20 SUMMARY: PASS=$PASS FAIL=$FAIL ====="
+[[ "$FAIL" -eq 0 ]] || exit 1