1// Flags: --no-warnings
2// Copyright Joyent, Inc. and other Node contributors.
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10// following conditions:
11//
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14//
15// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
16// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
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20// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
21// USE OR OTHER DEALINGS IN THE SOFTWARE.
22
23'use strict';
24const common = require('../common');
25if (!common.hasCrypto)
26  common.skip('missing crypto');
27
28if (!common.opensslCli)
29  common.skip('missing openssl-cli');
30
31const assert = require('assert');
32const { X509Certificate } = require('crypto');
33const { once } = require('events');
34const tls = require('tls');
35const { execFile } = require('child_process');
36const fixtures = require('../common/fixtures');
37
38const key = fixtures.readKey('agent2-key.pem');
39const cert = fixtures.readKey('agent2-cert.pem');
40
41// Prefer DHE over ECDHE when possible.
42const dheCipher = 'DHE-RSA-AES128-SHA256';
43const ecdheCipher = 'ECDHE-RSA-AES128-SHA256';
44const ciphers = `${dheCipher}:${ecdheCipher}`;
45
46// Test will emit a warning because the DH parameter size is < 2048 bits
47common.expectWarning('SecurityWarning',
48                     'DH parameter is less than 2048 bits');
49
50function loadDHParam(n) {
51  const keyname = `dh${n}.pem`;
52  return fixtures.readKey(keyname);
53}
54
55function test(dhparam, keylen, expectedCipher) {
56  const options = {
57    key,
58    cert,
59    ciphers,
60    dhparam,
61    maxVersion: 'TLSv1.2',
62  };
63
64  const server = tls.createServer(options, (conn) => conn.end());
65
66  server.listen(0, '127.0.0.1', common.mustCall(() => {
67    const args = ['s_client', '-connect', `127.0.0.1:${server.address().port}`,
68                  '-cipher', `${ciphers}:@SECLEVEL=1`];
69
70    execFile(common.opensslCli, args, common.mustSucceed((stdout) => {
71      assert(keylen === null ||
72             stdout.includes(`Server Temp Key: DH, ${keylen} bits`));
73      assert(stdout.includes(`Cipher    : ${expectedCipher}`));
74      server.close();
75    }));
76  }));
77
78  return once(server, 'close');
79}
80
81function testCustomParam(keylen, expectedCipher) {
82  const dhparam = loadDHParam(keylen);
83  if (keylen === 'error') keylen = null;
84  return test(dhparam, keylen, expectedCipher);
85}
86
87(async () => {
88  // By default, DHE is disabled while ECDHE is enabled.
89  for (const dhparam of [undefined, null]) {
90    await test(dhparam, null, ecdheCipher);
91  }
92
93  // The DHE parameters selected by OpenSSL depend on the strength of the
94  // certificate's key. For this test, we can assume that the modulus length
95  // of the certificate's key is equal to the size of the DHE parameter, but
96  // that is really only true for a few modulus lengths.
97  const {
98    publicKey: { asymmetricKeyDetails: { modulusLength } }
99  } = new X509Certificate(cert);
100  await test('auto', modulusLength, dheCipher);
101
102  assert.throws(() => {
103    testCustomParam(512);
104  }, /DH parameter is less than 1024 bits/);
105
106  // Custom DHE parameters are supported (but discouraged).
107  await testCustomParam(1024, dheCipher);
108  await testCustomParam(2048, dheCipher);
109
110  // Invalid DHE parameters are discarded. ECDHE remains enabled.
111  await testCustomParam('error', ecdheCipher);
112})().then(common.mustCall());
113