Merge dc/DC-072-exec-scope: DC-072 exec scope + containerId hardening (glm-grade=A)

Pre-fix, dashcaddy-api/routes/exec.js (the ws://host/ws/exec/:containerId
WebSocket container terminal endpoint) captured auth.scope at lines 39/46
but never enforced it — any API key or JWT, regardless of scope, got a
full PTY-backed shell inside the running container. A key issued with
scope ['read'] (a legitimate monitoring/observability scope) could
escalate to a root-equivalent shell. Container exec is full root inside
the container's user namespace, so this was a privilege-escalation across
the auth trust boundary.

Fix:
1. assertExecScope(auth) requires scope.includes('admin'); throws a
   tagged 403 error (DC-072_INSUFFICIENT_SCOPE) on rejection with
   requiredScope + actualScope in the envelope.
2. Called BEFORE wss.handleUpgrade so the WS gate cannot be bypassed.
3. 403 over the upgrade socket is JSON (code, requiredScope, actualScope)
   so the dashboard can show operator-actionable messages.
4. isValidContainerId(id) tightened to Docker's actual charset
   (12 or 64 lowercase hex). Pre-fix regex accepted _, -, ., mixed
   case, and any length up to 128; Docker would 404 the inspect and the
   rejection surfaced as a generic 500.
5. Audit-log pair: session start (container name + auth id) and session
   end with durationMs + reason ('exec-stream-end' vs 'ws-close'
   for abnormal disconnects); idempotent via ended-flag guard.
6. Both helpers exported via __test for unit tests (no live WS).

Tests: 20 new tests in __tests__/routes/exec.routes.test.js cover:
- assertExecScope: admin passes; read/write/empty/undefined/null/non-array
  rejected with the canonical 403 envelope.
- isValidContainerId: 12/64 lowercase hex accepted; uppercase / mixed /
  non-hex / _.- / wrong length / null / non-string / padded / CRLF
  payload rejected.

Full suite: 2327/2327 tests passing across 100 suites (zero regressions).

GLM-5.3 round 1: A with 2 LOW polish (scope-coercion defensive comment +
abnormal-close audit-log fallback). Both folded into the same commit.
Round 2: A. Ship.

dashcaddy-api/__tests__/routes/caddycode-dc070.routes.test.js

@@ -0,0 +1,277 @@
+/**
+ * DC-070: Caddycode config sanitization — validate the structural config
+ * that flows into generateSiteBlock(), and confirm that the post-fix
+ * generation does NOT interpolate raw user input into Caddyfile text.
+ *
+ * The endpoint /caddycode/generate was, pre-fix, the single most exposed
+ * surface in the Caddy-as-code path: every JSON field flowed verbatim into
+ * the Caddyfile text that /caddycode→POST /load feeds to Caddy.
+ *
+ * Bug class under test:
+ *   1. CRLF / newline in `domain` → close the block and inject a new site
+ *   2. `"` (quote) in a header value → break out of the quoted-string
+ *      context and append arbitrary directives
+ *   3. `}` in `tls`, `authService`, `stripPrefix`, or `upstream` →
+ *      prematurely close the parent block (or open a new one)
+ *   4. `://` or `;` in `upstream` → header injection / path smuggling
+ *
+ * Post-fix: validateGenerationConfig rejects every one of these at the
+ * route layer with 400 + enumerable errors; the helper-level tests here
+ * pin the rejection rules independent of the route.
+ */
+
+const { __test } = require('../../routes/caddycode');
+const { validateGenerationConfig, escapeCaddyQuotedString, generateSiteBlock } = __test;
+
+const BASE_OK = {
+  domain: 'app.example.com',
+  upstream: 'localhost:8080',
+};
+
+function check(cond, msg) {
+  if (!cond) throw new Error('assertion failed: ' + msg);
+}
+
+describe('DC-070: caddycode config sanitization', () => {
+  describe('validateGenerationConfig — happy paths', () => {
+    test('minimal valid config passes', () => {
+      const r = validateGenerationConfig(BASE_OK);
+      check(r.valid === true, `expected valid=true, got errors=${JSON.stringify(r.errors)}`);
+      check(Array.isArray(r.errors) && r.errors.length === 0, 'expected no errors');
+    });
+
+    test('full valid config (auth + headers + stripPrefix + tls CA) passes', () => {
+      const r = validateGenerationConfig({
+        domain: 'chat.example.com',
+        upstream: 'localhost:8096',
+        tls: 'letsencrypt',
+        auth: true,
+        authService: 'chat',
+        upstreamProtocol: 'https',
+        headers: {
+          'X-Frame-Options': 'DENY',
+          'X-Content-Type-Options': 'nosniff',
+          'Strict-Transport-Security': 'max-age=63072000',
+        },
+        stripPrefix: '/api/v1',
+      });
+      check(r.valid === true, `expected valid, got errors=${JSON.stringify(r.errors)}`);
+    });
+
+    test('IPv6 bracket-form upstream accepted', () => {
+      const r = validateGenerationConfig({ domain: 'dns.example.com', upstream: '[::1]:5380' });
+      check(r.valid === true, `IPv6 bracket should pass: ${JSON.stringify(r.errors)}`);
+    });
+
+    test('bare host without :port rejected (DC-070 round 2)', () => {
+      // Round-1 polish: Caddy reverse_proxy requires an explicit :port
+      // segment. A bare `localhost` would produce a Caddyfile that
+      // either fails to reload or silently picks a default port.
+      const r = validateGenerationConfig({ domain: 'app.example.com', upstream: 'localhost' });
+      check(r.valid === false, `bare host should reject: ${JSON.stringify(r.errors)}`);
+    });
+
+    test('upstream with non-numeric port rejected', () => {
+      const r = validateGenerationConfig({ domain: 'app.example.com', upstream: 'localhost:abc' });
+      check(r.valid === false, `non-numeric port should reject: ${JSON.stringify(r.errors)}`);
+    });
+  });
+
+  describe('validateGenerationConfig — injection rejection', () => {
+    test('CRLF in domain rejected', () => {
+      const r = validateGenerationConfig({ ...BASE_OK, domain: 'evil.com\nnew.site.example.com {' });
+      check(r.valid === false, 'CRLF should reject');
+      check(r.errors.some((e) => /domain/.test(e)), `expected error to mention domain, got ${JSON.stringify(r.errors)}`);
+    });
+
+    test('brace in domain rejected', () => {
+      const r = validateGenerationConfig({ ...BASE_OK, domain: 'evil} malicious' });
+      check(r.valid === false, 'brace should reject');
+    });
+
+    test('"://" in upstream rejected', () => {
+      const r = validateGenerationConfig({ ...BASE_OK, upstream: 'http://evil.tld/x' });
+      check(r.valid === false, ':// should reject');
+    });
+
+    test('space + brace in upstream rejected', () => {
+      const r = validateGenerationConfig({ ...BASE_OK, upstream: 'localhost:8080 } evil {' });
+      check(r.valid === false, 'whitespace+brace in upstream should reject');
+    });
+
+    test('CRLF in header value rejected', () => {
+      const r = validateGenerationConfig({
+        ...BASE_OK,
+        headers: { 'X-Custom': 'innocent\r\nHost: evil.tld' },
+      });
+      check(r.valid === false, 'CRLF in header value should reject');
+      check(r.errors.some((e) => /CR or LF/i.test(e)), `expected CR/LF error: ${JSON.stringify(r.errors)}`);
+    });
+
+    test('bad header key charset rejected', () => {
+      const r = validateGenerationConfig({
+        ...BASE_OK,
+        headers: { 'X Bad Key': 'innocent' },
+      });
+      check(r.valid === false, 'space in header key should reject');
+    });
+
+    test('non-string tls rejected', () => {
+      const r = validateGenerationConfig({ ...BASE_OK, tls: 'evil directive' });
+      check(r.valid === false, 'whitespace+word tls should reject');
+    });
+
+    test('empty authService when auth=true rejected', () => {
+      const r = validateGenerationConfig({ ...BASE_OK, auth: true });
+      check(r.valid === false, 'auth=true requires authService');
+    });
+
+    test('upstreamProtocol other than http/https rejected', () => {
+      const r = validateGenerationConfig({ ...BASE_OK, upstreamProtocol: 'javascript' });
+      check(r.valid === false, 'non-http protocol should reject');
+    });
+
+    test('stripPrefix without leading slash rejected', () => {
+      const r = validateGenerationConfig({ ...BASE_OK, stripPrefix: 'app/v1' });
+      check(r.valid === false, 'stripPrefix without leading slash should reject');
+    });
+
+    test('stripPrefix with brace rejected', () => {
+      const r = validateGenerationConfig({ ...BASE_OK, stripPrefix: '/api/{evil}' });
+      check(r.valid === false, 'stripPrefix with brace should reject');
+    });
+
+    test('multiple errors returned together (enumerable)', () => {
+      const r = validateGenerationConfig({
+        domain: 'evil }',
+        upstream: 'localhost:8080 } malicious {',
+        tls: 'bad tls',
+        auth: true,
+        headers: { 'X B': 'oops' },
+      });
+      check(r.valid === false, 'should reject');
+      check(r.errors.length >= 4, `expected multiple errors, got ${r.errors.length}: ${JSON.stringify(r.errors)}`);
+    });
+  });
+
+  describe('escapeCaddyQuotedString', () => {
+    test('escapes backslash and quote', () => {
+      check(escapeCaddyQuotedString('a"b\\c') === 'a\\"b\\\\c', 'should escape both');
+    });
+
+    test('safe string passes through verbatim', () => {
+      check(escapeCaddyQuotedString('hello') === 'hello', 'safe string unchanged');
+    });
+
+    test('empty string survives', () => {
+      check(escapeCaddyQuotedString('') === '', 'empty string survives');
+    });
+  });
+
+  describe('generateSiteBlock — quote-breakout defence-in-depth', () => {
+    test('post-validation, header value with " is properly escaped', () => {
+      // The validator REJECTS this upstream (CRLF + quote) but the
+      // generator must also escape `"` even if a future code path bypasses
+      // validation. This test pins the dual-defence.
+      const cfg = {
+        domain: 'app.example.com',
+        upstream: 'localhost:8080',
+        headers: { 'X-Custom': 'a"b' },
+      };
+      // The validator rejects CRLF + chars outside the charset, but a bare
+      // `"` is technically allowed by /[\r\n]/ (only CR/LF). However the
+      // GENERATOR must still escape it. Verify by calling generateSiteBlock
+      // directly with a manually-validated config.
+      const out = generateSiteBlock(cfg);
+      // The header line should appear as:   X-Custom "a\"b"
+      // i.e. the raw `"` in the value MUST be escaped, otherwise the Caddyfile
+      // line breaks out of the quoted context.
+      check(out.includes('X-Custom "a\\"b"'), `expected escaped quote, got: ${out}`);
+    });
+  });
+
+  describe('route integration — /caddycode/generate wires validation', () => {
+    const express = require('express');
+    const request = require('supertest');
+    const routes = require('../../routes/caddycode');
+
+    function buildApp() {
+      const app = express();
+      app.use(express.json());
+      const wrap = (fn) => (req, res, next) => Promise.resolve(fn(req, res, next)).catch(next);
+      return { app, wrap };
+    }
+
+    test('valid config → 200 + caddyfile', async () => {
+      const { app, wrap } = buildApp();
+      app.use('/api/v1', routes({ asyncHandler: wrap }));
+      const res = await request(app)
+        .post('/api/v1/caddycode/generate')
+        .send({ domain: 'app.example.com', upstream: 'localhost:8080' });
+      check(res.status === 200, `expected 200, got ${res.status}`);
+      check(typeof res.body.caddyfile === 'string', 'expected caddyfile string');
+      check(res.body.caddyfile.includes('app.example.com'), 'caddyfile should include domain');
+    });
+
+    test('CRLF in domain → 400 + enumerable errors', async () => {
+      const { app, wrap } = buildApp();
+      app.use('/api/v1', routes({ asyncHandler: wrap }));
+      const res = await request(app)
+        .post('/api/v1/caddycode/generate')
+        .send({ domain: 'evil.com\nnew block', upstream: 'localhost:8080' });
+      check(res.status === 400, `expected 400, got ${res.status}: ${JSON.stringify(res.body)}`);
+      check(res.body.success === false, 'success should be false');
+      check(Array.isArray(res.body.errors), `expected enumerable errors array, got body=${JSON.stringify(res.body)}`);
+      check(res.body.errors.length >= 1, 'at least one error');
+    });
+
+    test('"://" in upstream → 400', async () => {
+      const { app, wrap } = buildApp();
+      app.use('/api/v1', routes({ asyncHandler: wrap }));
+      const res = await request(app)
+        .post('/api/v1/caddycode/generate')
+        .send({ domain: 'app.example.com', upstream: 'http://evil.tld/x' });
+      check(res.status === 400, `expected 400, got ${res.status}`);
+    });
+
+    test('header with CRLF → 400 + specific error', async () => {
+      const { app, wrap } = buildApp();
+      app.use('/api/v1', routes({ asyncHandler: wrap }));
+      const res = await request(app)
+        .post('/api/v1/caddycode/generate')
+        .send({
+          domain: 'app.example.com',
+          upstream: 'localhost:8080',
+          headers: { 'X-Bad': 'oops\r\nHost: evil.tld' },
+        });
+      check(res.status === 400, `expected 400, got ${res.status}`);
+      check(res.body.errors.some((e) => /CR or LF/i.test(e)), `expected CR/LF mention: ${JSON.stringify(res.body.errors)}`);
+    });
+
+    test('end-to-end: header value with quote + backslash round-trips through generator', async () => {
+      // DC-070 round-2 polish (per GLM-5.3 review): the unit tests pin the
+      // escape helper and the route reject path independently, but nothing
+      // asserts the GENERATED Caddyfile is well-formed when a header value
+      // contains BOTH " and \. Verify the generator escapes both so the
+      // resulting line parses as a Caddyfile quoted string.
+      const { app, wrap } = buildApp();
+      app.use('/api/v1', routes({ asyncHandler: wrap }));
+      const res = await request(app)
+        .post('/api/v1/caddycode/generate')
+        .send({
+          domain: 'app.example.com',
+          upstream: 'localhost:8080',
+          headers: { 'X-Custom': 'a"b\\c' },
+        });
+      check(res.status === 200, `expected 200, got ${res.status}: ${JSON.stringify(res.body)}`);
+      const out = res.body.caddyfile;
+      check(typeof out === 'string', 'expected caddyfile string');
+      // The header line should be EXACTLY:  X-Custom "a\"b\\c"
+      // i.e. the raw `"` and `\` in the value MUST be escaped.
+      check(
+        /X-Custom "a\\"b\\\\c"/.test(out),
+        `expected escaped quote+backslash in generated Caddyfile, got: ${out}`
+      );
+    });
+  });
+});

dashcaddy-api/__tests__/routes/exec.routes.test.js

@@ -0,0 +1,192 @@
+/**
+ * DC-072: WebSocket exec scope-based authorization + containerId charset
+ * hardening.
+ *
+ * Bug class under test:
+ *   1. Pre-fix `routes/exec.js` captured `auth.scope` (line 39/46) but
+ *      NEVER enforced it. A JWT or API key whose scope was `['read']`
+ *      (a legitimate monitoring/observability scope) would be granted a
+ *      full PTY-backed shell inside any running container. Container
+ *      exec is root-equivalent inside the container's user namespace,
+ *      so this is a privilege escalation: a read-only key holder could
+ *      run arbitrary commands, exfiltrate mounted volumes, or pivot
+ *      to the host network.
+ *
+ *   2. Pre-fix `containerId` regex `/^[a-zA-Z0-9][a-zA-Z0-9_.-]{0,127}$/`
+ *      accepted mixed case, `_`, `-`, `.`, and any length up to 128.
+ *      Docker container IDs are exactly 64 lowercase hex (or 12-char
+ *      short form). The pre-fix validator would pass any string that
+ *      looked vaguely ID-shaped; Docker's inspect() would then 404.
+ *
+ * Post-fix: `assertExecScope(auth)` requires `admin` scope and throws a
+ * 403-tagged error. `isValidContainerId(id)` accepts only 12 or 64
+ * lowercase hex chars. Both helpers are exported via `__test`.
+ */
+
+const { __test } = require('../../routes/exec');
+const { assertExecScope, isValidContainerId } = __test;
+
+function check(cond, msg) {
+  if (!cond) throw new Error('assertion failed: ' + msg);
+}
+
+describe('DC-072: exec WebSocket scope-based authorization', () => {
+  describe('assertExecScope — admin required', () => {
+    test('admin scope passes', () => {
+      // Should not throw
+      assertExecScope({ type: 'jwt', scope: ['admin'] });
+      assertExecScope({ type: 'apikey', scope: ['admin', 'read'] });
+    });
+
+    test('read-only scope rejected with DC-072_INSUFFICIENT_SCOPE', () => {
+      let caught = null;
+      try {
+        assertExecScope({ type: 'apikey', scope: ['read'] });
+      } catch (e) {
+        caught = e;
+      }
+      check(caught !== null, 'expected assertExecScope to throw on read-only scope');
+      check(caught.code === 'DC-072_INSUFFICIENT_SCOPE', `expected code DC-072_INSUFFICIENT_SCOPE, got ${caught.code}`);
+      check(caught.statusCode === 403, `expected statusCode 403, got ${caught.statusCode}`);
+      check(caught.requiredScope === 'admin', `expected requiredScope=admin, got ${caught.requiredScope}`);
+      check(Array.isArray(caught.actualScope) && caught.actualScope[0] === 'read', `expected actualScope=['read'], got ${JSON.stringify(caught.actualScope)}`);
+    });
+
+    test('write-only scope rejected (write ≠ admin)', () => {
+      let caught = null;
+      try {
+        assertExecScope({ type: 'jwt', scope: ['write'] });
+      } catch (e) {
+        caught = e;
+      }
+      check(caught !== null, 'expected assertExecScope to throw on write-only scope');
+      check(caught.code === 'DC-072_INSUFFICIENT_SCOPE', `expected code DC-072_INSUFFICIENT_SCOPE, got ${caught.code}`);
+      check(caught.statusCode === 403, `expected statusCode 403, got ${caught.statusCode}`);
+    });
+
+    test('empty scope rejected', () => {
+      let caught = null;
+      try {
+        assertExecScope({ type: 'apikey', scope: [] });
+      } catch (e) {
+        caught = e;
+      }
+      check(caught !== null, 'expected assertExecScope to throw on empty scope');
+      check(caught.code === 'DC-072_INSUFFICIENT_SCOPE', 'expected DC-072_INSUFFICIENT_SCOPE code');
+    });
+
+    test('undefined scope rejected (null-safety)', () => {
+      let caught = null;
+      try {
+        assertExecScope({ type: 'jwt' }); // no scope field
+      } catch (e) {
+        caught = e;
+      }
+      check(caught !== null, 'expected assertExecScope to throw on undefined scope');
+      check(caught.code === 'DC-072_INSUFFICIENT_SCOPE', 'expected DC-072_INSUFFICIENT_SCOPE code');
+    });
+
+    test('null auth rejected', () => {
+      let caught = null;
+      try {
+        assertExecScope(null);
+      } catch (e) {
+        caught = e;
+      }
+      check(caught !== null, 'expected assertExecScope to throw on null auth');
+      check(caught.code === 'DC-072_INSUFFICIENT_SCOPE', 'expected DC-072_INSUFFICIENT_SCOPE code');
+    });
+
+    test('non-array scope rejected (defensive)', () => {
+      let caught = null;
+      try {
+        assertExecScope({ type: 'apikey', scope: 'admin' }); // string, not array
+      } catch (e) {
+        caught = e;
+      }
+      check(caught !== null, 'expected assertExecScope to throw on non-array scope');
+      check(caught.code === 'DC-072_INSUFFICIENT_SCOPE', 'expected DC-072_INSUFFICIENT_SCOPE code');
+    });
+
+    test('error envelope carries operator-actionable fields', () => {
+      let caught = null;
+      try {
+        assertExecScope({ type: 'apikey', keyId: 'k_test', scope: ['read'] });
+      } catch (e) {
+        caught = e;
+      }
+      check(caught.message === 'Container exec requires admin scope', `expected canonical message, got ${caught.message}`);
+      check(typeof caught.requiredScope === 'string' && caught.requiredScope === 'admin', 'requiredScope present');
+      check(Array.isArray(caught.actualScope), 'actualScope is array');
+    });
+  });
+
+  describe('isValidContainerId — Docker charset (12 or 64 lowercase hex)', () => {
+    test('64-char lowercase hex accepted (full Docker ID)', () => {
+      // Real-world example: dashcaddy-api container ID
+      check(isValidContainerId('abcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789') === true, '64-char hex should pass');
+    });
+
+    test('12-char lowercase hex accepted (short form)', () => {
+      check(isValidContainerId('abcdef012345') === true, '12-char hex should pass');
+    });
+
+    test('uppercase hex rejected (Docker IDs are lowercase)', () => {
+      check(isValidContainerId('ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789') === false, 'uppercase 64-char should fail');
+      check(isValidContainerId('ABCDEF012345') === false, 'uppercase 12-char should fail');
+    });
+
+    test('mixed case rejected', () => {
+      check(isValidContainerId('Abcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789') === false, 'mixed case 64-char should fail');
+    });
+
+    test('non-hex chars rejected', () => {
+      check(isValidContainerId('zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz') === false, 'g-z hex should fail');
+      check(isValidContainerId('abc!@#$%^&*()_+-=[]{}|\\:;\'",.<>/?0123456789012345678901234567890123') === false, 'special chars should fail');
+    });
+
+    test('underscore / dot / dash rejected (pre-fix allowed these)', () => {
+      // Pre-fix regex accepted `_`, `-`, `.` — all are non-Docker
+      check(isValidContainerId('my_container_1') === false, 'underscore should fail');
+      check(isValidContainerId('my.container.1') === false, 'dot should fail');
+      check(isValidContainerId('my-container-1') === false, 'dash should fail');
+    });
+
+    test('wrong length rejected', () => {
+      check(isValidContainerId('abcdef0123456') === false, '13-char should fail');     // 12 + 1
+      check(isValidContainerId('abcdef01234567') === false, '14-char should fail');   // 12 + 2
+      check(isValidContainerId('abcdef0123456789a') === false, '65-char should fail'); // 64 + 1
+    });
+
+    test('empty string rejected', () => {
+      check(isValidContainerId('') === false, 'empty string should fail');
+    });
+
+    test('null / undefined / non-string rejected (defensive)', () => {
+      check(isValidContainerId(null) === false, 'null should fail');
+      check(isValidContainerId(undefined) === false, 'undefined should fail');
+      check(isValidContainerId(12345) === false, 'number should fail');
+      check(isValidContainerId({}) === false, 'object should fail');
+      check(isValidContainerId([]) === false, 'array should fail');
+    });
+
+    test('whitespace / padding rejected', () => {
+      check(isValidContainerId('  abcdef012345  ') === false, 'padded should fail');
+      check(isValidContainerId('\nabcdef012345\n') === false, 'CRLF-padded should fail');
+    });
+
+    test('CRLF injection rejected (defensive against pre-fix attack class)', () => {
+      // Pre-fix regex accepted 128 chars with dots; a payload like
+      // `aa.bb.cc.dd\r\nSet-Cookie:...` would have passed. Post-fix
+      // the LF + non-hex + wrong-length combo fails on every axis.
+      check(isValidContainerId('aa\r\nbb') === false, 'CRLF payload should fail');
+    });
+  });
+
+  describe('__test exports shape', () => {
+    test('exports assertExecScope and isValidContainerId', () => {
+      check(typeof __test.assertExecScope === 'function', 'assertExecScope is a function');
+      check(typeof __test.isValidContainerId === 'function', 'isValidContainerId is a function');
+    });
+  });
+});

dashcaddy-api/routes/caddycode.js

@@ -11,10 +11,138 @@
  */
 const express = require('express');
 const { ok, errorResponse } = require('../src/utils/responses');
+const { REGEX } = require('../src/utilities/constants');
+
+/**
+ * DC-070: Validate the structural config that flows into generateSiteBlock.
+ *
+ * Threat model: `generateSiteBlock` interpolates user-controlled fields
+ * (domain, tls, authService, headers.*, stripPrefix, upstream) DIRECTLY into
+ * a Caddyfile text block that is later fed to `caddy.modify()` and the
+ * Caddy admin /load endpoint. The /caddycode/generate endpoint is
+ * authenticated (forward_auth gated), but the bug class is "compromised
+ * middleware / pivot" — a JSON-only payload can be smuggled past any
+ * UI-side input checks.
+ *
+ * Pre-fix, every field was trusted: `lines.push(`${domain} {`)` accepted any
+ * string (including newlines that close the block and inject a new site),
+ * `headers[key] = "${value}"` accepted arbitrary quotes (which would break
+ * the surrounding `"..."` Caddy quoted-string context and inject directives),
+ * and `tls`, `authService`, `stripPrefix`, `upstream` had no charset
+ * restrictions at all (spaces, braces, semicolons would land verbatim).
+ *
+ * Post-fix: every field is constrained to a known-safe character class
+ * BEFORE interpolation, and CRLF is rejected outright. Quoted-string
+ * injection in header values is closed by escaping `\` and `"` per the
+ * Caddy quoted-string spec (backslash escapes the next character).
+ */
+function validateGenerationConfig(config) {
+  const errors = [];
+  const {
+    domain,
+    upstream,
+    upstreamProtocol = 'http',
+    tls = 'auto',
+    auth = false,
+    authService = null,
+    headers = {},
+    stripPrefix = null,
+  } = config;
+
+  // 1. domain — RFC 1123 hostname. Reject anything with whitespace, brace,
+  //    semicolon, newline, or non-printable. REGEX.DOMAIN is
+  //    /^[a-z0-9]([a-z0-9.-]{0,251}[a-z0-9])?$/i in constants.js.
+  if (typeof domain !== 'string' || !REGEX.DOMAIN.test(domain)) {
+    errors.push('domain must be a valid hostname (letters, digits, dots, hyphens)');
+  }
+
+  // 2. upstream — `host:port` form (the only shape Caddy's reverse_proxy
+  //    directive takes for non-URL upstreams). Reject `://`, whitespace,
+  //    braces. Allow optional IPv6 bracket form `[::1]:5000`. Must
+  //    include an explicit :port segment — a bare `localhost` would
+  //    produce a Caddyfile that fails to reload (port required for
+  //    reverse_proxy upstreams). Two regex branches: (a) bare host with
+  //    required :port, (b) bracketed IPv6 literal with required :port.
+  if (typeof upstream !== 'string'
+      || !/^[a-z0-9.\-]+:\d{1,5}$/i.test(upstream)
+      && !/^\[[a-z0-9.\-:.]+\]:\d{1,5}$/i.test(upstream)
+  ) {
+    errors.push('upstream must be host:port (host letters/digits/dots/hyphens, port 1-65535, optional IPv6 brackets)');
+  }
+
+  // 3. tls — either the literal strings 'auto' / 'internal' (handled
+  //    specially below) OR a CA name like 'letsencrypt' / 'internal' that
+  //    must match /^[a-z0-9._-]+$/i. Reject whitespace + braces + quotes.
+  if (typeof tls !== 'string' || !/^[a-z0-9._-]+$/i.test(tls)) {
+    errors.push('tls must be one of: auto, internal, or a CA name (letters, digits, dots, underscores, hyphens)');
+  }
+
+  // 4. authService — only meaningful when auth=true; otherwise ignore. Must
+  //    match the existing SSO service-id charset (REGEX.SUBDOMAIN).
+  if (auth) {
+    if (typeof authService !== 'string' || !REGEX.SUBDOMAIN.test(authService)) {
+      errors.push('authService must be a valid subdomain (lowercase, alphanumeric, hyphens)');
+    }
+  }
+
+  // 5. upstreamProtocol — only 'http' or 'https'. Anything else gets coerced
+  //    to 'http' but only after we explicitly accept it; reject obvious
+  //    injection vectors here.
+  if (upstreamProtocol !== 'http' && upstreamProtocol !== 'https') {
+    errors.push('upstreamProtocol must be "http" or "https"');
+  }
+
+  // 6. headers — each key must be a valid HTTP header name ([A-Za-z0-9-]+),
+  //    each value must be a string with no CR/LF and no unescaped quotes.
+  if (headers && typeof headers === 'object') {
+    for (const [key, value] of Object.entries(headers)) {
+      if (typeof key !== 'string' || !/^[A-Za-z0-9-]+$/.test(key)) {
+        errors.push(`header key "${String(key)}" must be HTTP-token chars only ([A-Za-z0-9-])`);
+      }
+      if (typeof value !== 'string') {
+        errors.push(`header "${key}" value must be a string`);
+        continue;
+      }
+      if (/[\r\n]/.test(value)) {
+        errors.push(`header "${key}" value must not contain CR or LF`);
+      }
+    }
+  }
+
+  // 7. stripPrefix — must be a leading-slash path with safe chars. Reject
+  //    braces, quotes, whitespace, and { } which would let the attacker
+  //    open a new Caddyfile block.
+  if (stripPrefix != null) {
+    if (typeof stripPrefix !== 'string' || !/^\/[A-Za-z0-9._\-/]*$/.test(stripPrefix)) {
+      errors.push('stripPrefix must be an absolute path (letters, digits, dots, hyphens, slashes)');
+    }
+  }
+
+  return { valid: errors.length === 0, errors };
+}
+
+/**
+ * Escape a string for safe interpolation inside a Caddyfile quoted-string
+ * context. Caddy uses the same backslash-escape semantics as JSON-ish
+ * contexts — `\` and `"` MUST be escaped, otherwise the attacker breaks out
+ * of the quoted string and injects arbitrary directives.
+ *
+ * @param {string} s raw header value
+ * @returns {string} escaped value (no embedded newlines; CR/LF were already
+ *   rejected by the validator)
+ */
+function escapeCaddyQuotedString(s) {
+  return String(s).replace(/\\/g, '\\\\').replace(/"/g, '\\"');
+}
 
 /**
  * Generate a Caddyfile site block from a structured config.
- * @param {Object} config - Site configuration
+ *
+ * Every interpolated field is now validated by `validateGenerationConfig`
+ * first (see DC-070). Quoted-string values are escaped via
+ * `escapeCaddyQuotedString` so a `"` in a header value cannot break out.
+ *
+ * @param {Object} config - Site configuration (already validated)
  * @returns {string} Caddyfile snippet
  */
 function generateSiteBlock(config) {
@@ -38,12 +166,15 @@ function generateSiteBlock(config) {
   const lines = [];
   lines.push(`${domain} {`);
 
-  // TLS
+  // TLS — only emit a tls directive when explicitly 'internal' or a CA
+  // name; 'auto' means Caddy's default behaviour (no directive needed).
   if (tls === 'internal') {
     lines.push(`  tls internal`);
   } else if (tls === 'auto') {
     // Default — Caddy auto-provisions Let's Encrypt
-  } else if (typeof tls === 'string') {
+  } else {
+    // CA name validated by validateGenerationConfig against
+    // /^[a-z0-9._-]+$/i — safe to interpolate verbatim.
     lines.push(`  tls ${tls}`);
   }
 
@@ -52,7 +183,8 @@ function generateSiteBlock(config) {
     lines.push(`  # Redirect HTTP to HTTPS is automatic in Caddy 2`);
   }
 
-  // Auth gate (DashCaddy forward_auth)
+  // Auth gate (DashCaddy forward_auth) — authService validated by
+  // validateGenerationConfig against REGEX.SUBDOMAIN — safe to interpolate.
   if (auth && authService) {
     lines.push(`  import dashcaddy_auth ${authService}`);
   }
@@ -66,16 +198,17 @@ function generateSiteBlock(config) {
     lines.push(`  }`);
   }
 
-  // Custom headers
-  if (Object.keys(headers).length > 0) {
+  // Custom headers — keys validated against /^[A-Za-z0-9-]+$/, values
+  // escaped via escapeCaddyQuotedString before being placed inside "..."
+  if (headers && typeof headers === 'object' && Object.keys(headers).length > 0) {
     lines.push(`  header {`);
     for (const [key, value] of Object.entries(headers)) {
-      lines.push(`    ${key} "${value}"`);
+      lines.push(`    ${key} "${escapeCaddyQuotedString(value)}"`);
     }
     lines.push(`  }`);
   }
 
-  // Strip prefix
+  // Strip prefix — validated to /^\/[A-Za-z0-9._\-/]*$/ — safe.
   if (stripPrefix) {
     lines.push(`  uri strip_prefix ${stripPrefix}`);
   }
@@ -118,6 +251,19 @@ module.exports = function({ asyncHandler }) {
       return errorResponse(res, 400, 'upstream is required (e.g. localhost:8080)');
     }
 
+    // DC-070: structural validation BEFORE interpolation. Every field that
+    // flows into the Caddyfile text must satisfy a known-safe charset rule,
+    // and CRLF is rejected outright. Run this BEFORE generateSiteBlock so
+    // the bad input is rejected with a clean 400 + enumerable error list,
+    // not a generated-Caddyfile + 500.
+    const validation = validateGenerationConfig(config);
+    if (!validation.valid) {
+      return errorResponse(res, 400, 'Invalid configuration', {
+        code: 'DC-CCD-700',
+        errors: validation.errors,
+      });
+    }
+
     try {
       const caddyfile = generateSiteBlock(config);
       ok(res, { caddyfile, config });
@@ -225,3 +371,11 @@ module.exports = function({ asyncHandler }) {
 
   return router;
 };
+
+// DC-070: export helpers for unit-testing the sanitization surface
+// independently of the route handler.
+module.exports.__test = {
+  validateGenerationConfig,
+  escapeCaddyQuotedString,
+  generateSiteBlock,
+};

dashcaddy-api/routes/exec.js

@@ -4,6 +4,50 @@ const url = require('url');
 
 const docker = new Docker();
 
+/**
+ * DC-072: WebSocket scope authorization — admin-only by default.
+ *
+ * Container exec is full root-equivalent access inside the target
+ * container. Granting it to a key whose scope is `['read']` violates
+ * least privilege. The validScopes list (`['read','write','admin']`)
+ * is defined in routes/auth/keys.js; exec requires `admin`.
+ *
+ * Defensive: the scope field is coerced via `Array.isArray(...) ? ... : []`
+ * so a malformed payload (string, object, null, undefined) cannot reach
+ * `.includes('admin')` and accidentally grant access. Every malformed
+ * shape falls into the rejection branch with the same 403 envelope.
+ *
+ * Tests should call `__test.assertExecScope(auth)` directly rather
+ * than spinning up a WebSocket server.
+ */
+function assertExecScope(auth) {
+  const scope = Array.isArray(auth && auth.scope) ? auth.scope : [];
+  if (!scope.includes('admin')) {
+    const err = new Error('Container exec requires admin scope');
+    err.code = 'DC-072_INSUFFICIENT_SCOPE';
+    err.statusCode = 403;
+    err.requiredScope = 'admin';
+    err.actualScope = scope;
+    throw err;
+  }
+}
+
+/**
+ * DC-072: Tighten containerId validation.
+ *
+ * Docker container IDs are exactly 64 lowercase hex chars (or 12-char
+ * short form). The pre-fix regex accepted `_`, `-`, `.`, mixed case,
+ * and up to 128 chars — Docker would then 404 the inspect call and
+ * the rejection would surface as a generic 500 in the WS error
+ * envelope. Pre-validate at the upgrade layer so the rejection is
+ * fast and the log line discriminates "malformed" from "unknown".
+ */
+function isValidContainerId(id) {
+  if (typeof id !== 'string') return false;
+  // Full 64-char hex, or 12-char short hex
+  return /^[0-9a-f]{64}$/.test(id) || /^[0-9a-f]{12}$/.test(id);
+}
+
 /**
  * Attach WebSocket server for container exec/shell
  * Route: ws://host/ws/exec/:containerId
@@ -21,8 +65,8 @@ module.exports = function attachExecWS(server, log, authManager) {
 
     const containerId = decodeURIComponent(match[1]);
 
-    // Validate container ID format to prevent injection
-    if (!/^[a-zA-Z0-9][a-zA-Z0-9_.-]{0,127}$/.test(containerId)) {
+    // DC-072: Tighten containerId charset (64-char / 12-char lowercase hex)
+    if (!isValidContainerId(containerId)) {
       log.warn('exec', 'Invalid container ID in WebSocket path', { containerId });
       socket.write('HTTP/1.1 400 Bad Request\r\n\r\n');
       socket.destroy();
@@ -55,6 +99,35 @@ module.exports = function attachExecWS(server, log, authManager) {
       return;
     }
 
+    // DC-072: Container exec is root-equivalent — require admin scope.
+    // Pre-fix, a key issued with scope `['read']` (e.g., for monitoring)
+    // would get a full PTY shell inside any running container. The
+    // `auth.scope` was captured at lines 39/46 but never checked.
+    try {
+      assertExecScope(auth);
+    } catch (err) {
+      log.warn('exec', 'Insufficient scope for exec attempt', {
+        containerId,
+        authType: auth.type,
+        authId: auth.type === 'jwt' ? auth.userId : auth.keyId,
+        actualScope: err.actualScope,
+        requiredScope: err.requiredScope,
+        ip: req.socket.remoteAddress,
+      });
+      // 403 with a JSON error envelope over the upgrade socket so the
+      // dashboard can display "admin required" instead of guessing.
+      socket.write('HTTP/1.1 403 Forbidden\r\n');
+      socket.write('Content-Type: application/json\r\n');
+      socket.write('\r\n');
+      socket.end(JSON.stringify({
+        error: err.message,
+        code: err.code,
+        requiredScope: err.requiredScope,
+        actualScope: err.actualScope,
+      }));
+      return;
+    }
+
     // Auth passed — proceed with WebSocket upgrade
     wss.handleUpgrade(req, socket, head, (ws) => {
       handleExec(ws, containerId, log, auth);
@@ -67,6 +140,7 @@ module.exports = function attachExecWS(server, log, authManager) {
 async function handleExec(ws, containerId, log, auth) {
   let execStream = null;
   let execInstance = null;
+  const sessionStart = Date.now();
 
   try {
     const container = docker.getContainer(containerId);
@@ -78,10 +152,13 @@ async function handleExec(ws, containerId, log, auth) {
       return;
     }
 
+    // DC-072: Audit-log the exec session start. Pairs with the end-log
+    // below so the operator can correlate who opened which shell.
     log.info('exec', 'Authenticated exec session started', {
       containerId,
       authType: auth.type,
-      authId: auth.type === 'jwt' ? auth.userId : auth.keyId
+      authId: auth.type === 'jwt' ? auth.userId : auth.keyId,
+      containerName: info.Name,
     });
 
     // Detect available shell
@@ -120,7 +197,28 @@ async function handleExec(ws, containerId, log, auth) {
       }
     });
 
+    // DC-072: Track whether the end-log has fired so we don't double-log
+    // when both execStream 'end' and ws 'close' fire (Docker stream end
+    // closes the WS, which then fires 'close' too — without the flag
+    // we'd emit the same audit line twice with the same durationMs).
+    let ended = false;
+    const logSessionEnd = (reason) => {
+      if (ended) return;
+      ended = true;
+      log.info('exec', 'Exec session ended', {
+        containerId,
+        authType: auth.type,
+        authId: auth.type === 'jwt' ? auth.userId : auth.keyId,
+        durationMs: Date.now() - sessionStart,
+        reason,
+      });
+    };
+
     execStream.on('end', () => {
+      // DC-072: Audit-log the session end (duration + container) so a
+      // long-running session is observable in the error log. Normal
+      // shutdown path: Docker exec stream closes → log + tell client.
+      logSessionEnd('exec-stream-end');
       if (ws.readyState === ws.OPEN) {
         ws.send(JSON.stringify({ type: 'exit' }));
         ws.close();
@@ -148,6 +246,11 @@ async function handleExec(ws, containerId, log, auth) {
     });
 
     ws.on('close', () => {
+      // DC-072: Fallback audit-log for abnormal close (browser tab
+      // closed, network drop, container killed mid-session) where the
+      // execStream 'end' event never fires. The ended-flag guard makes
+      // this idempotent with the normal path above.
+      logSessionEnd('ws-close');
       if (execStream) {
         try { execStream.destroy(); } catch (_) {
           // Ignore stream teardown errors on socket close
@@ -172,3 +275,11 @@ async function handleExec(ws, containerId, log, auth) {
     }
   }
 }
+
+// Internal-only export for unit tests. Stripped from the public
+// surface; tests import this via the destructure form
+// `const { __test } = require('./routes/exec')`.
+module.exports.__test = {
+  assertExecScope,
+  isValidContainerId,
+};