refactor(exec): centralize safe-bin policy checks

src/infra/exec-safe-bin-runtime-policy.ts

@@ -0,0 +1,127 @@
+import { resolveSafeBins } from "./exec-approvals-allowlist.js";
+import {
+  normalizeSafeBinProfileFixtures,
+  resolveSafeBinProfiles,
+  type SafeBinProfile,
+  type SafeBinProfileFixture,
+  type SafeBinProfileFixtures,
+} from "./exec-safe-bin-policy.js";
+import { getTrustedSafeBinDirs } from "./exec-safe-bin-trust.js";
+
+export type ExecSafeBinConfigScope = {
+  safeBins?: string[] | null;
+  safeBinProfiles?: SafeBinProfileFixtures | null;
+};
+
+const INTERPRETER_LIKE_SAFE_BINS = new Set([
+  "ash",
+  "bash",
+  "bun",
+  "cmd",
+  "cmd.exe",
+  "cscript",
+  "dash",
+  "deno",
+  "fish",
+  "ksh",
+  "lua",
+  "node",
+  "nodejs",
+  "perl",
+  "php",
+  "powershell",
+  "powershell.exe",
+  "pypy",
+  "pwsh",
+  "pwsh.exe",
+  "python",
+  "python2",
+  "python3",
+  "ruby",
+  "sh",
+  "wscript",
+  "zsh",
+]);
+
+const INTERPRETER_LIKE_PATTERNS = [
+  /^python\d+(?:\.\d+)?$/,
+  /^ruby\d+(?:\.\d+)?$/,
+  /^perl\d+(?:\.\d+)?$/,
+  /^php\d+(?:\.\d+)?$/,
+  /^node\d+(?:\.\d+)?$/,
+];
+
+function normalizeSafeBinName(raw: string): string {
+  const trimmed = raw.trim().toLowerCase();
+  if (!trimmed) {
+    return "";
+  }
+  const tail = trimmed.split(/[\\/]/).at(-1);
+  return tail ?? trimmed;
+}
+
+export function isInterpreterLikeSafeBin(raw: string): boolean {
+  const normalized = normalizeSafeBinName(raw);
+  if (!normalized) {
+    return false;
+  }
+  if (INTERPRETER_LIKE_SAFE_BINS.has(normalized)) {
+    return true;
+  }
+  return INTERPRETER_LIKE_PATTERNS.some((pattern) => pattern.test(normalized));
+}
+
+export function listInterpreterLikeSafeBins(entries: Iterable<string>): string[] {
+  return Array.from(entries)
+    .map((entry) => normalizeSafeBinName(entry))
+    .filter((entry) => entry.length > 0 && isInterpreterLikeSafeBin(entry))
+    .toSorted();
+}
+
+export function resolveMergedSafeBinProfileFixtures(params: {
+  global?: ExecSafeBinConfigScope | null;
+  local?: ExecSafeBinConfigScope | null;
+}): Record<string, SafeBinProfileFixture> | undefined {
+  const global = normalizeSafeBinProfileFixtures(params.global?.safeBinProfiles);
+  const local = normalizeSafeBinProfileFixtures(params.local?.safeBinProfiles);
+  if (Object.keys(global).length === 0 && Object.keys(local).length === 0) {
+    return undefined;
+  }
+  return {
+    ...global,
+    ...local,
+  };
+}
+
+export function resolveExecSafeBinRuntimePolicy(params: {
+  global?: ExecSafeBinConfigScope | null;
+  local?: ExecSafeBinConfigScope | null;
+  pathEnv?: string | null;
+}): {
+  safeBins: Set<string>;
+  safeBinProfiles: Readonly<Record<string, SafeBinProfile>>;
+  trustedSafeBinDirs: ReadonlySet<string>;
+  unprofiledSafeBins: string[];
+  unprofiledInterpreterSafeBins: string[];
+} {
+  const safeBins = resolveSafeBins(params.local?.safeBins ?? params.global?.safeBins);
+  const safeBinProfiles = resolveSafeBinProfiles(
+    resolveMergedSafeBinProfileFixtures({
+      global: params.global,
+      local: params.local,
+    }),
+  );
+  const unprofiledSafeBins = Array.from(safeBins)
+    .filter((entry) => !safeBinProfiles[entry])
+    .toSorted();
+  const trustedSafeBinDirs = params.pathEnv
+    ? getTrustedSafeBinDirs({ pathEnv: params.pathEnv })
+    : getTrustedSafeBinDirs();
+  return {
+    safeBins,
+    safeBinProfiles,
+    trustedSafeBinDirs,
+    unprofiledSafeBins,
+    unprofiledInterpreterSafeBins: listInterpreterLikeSafeBins(unprofiledSafeBins),
+  };
+}