xref: /openbmc/bmcweb/src/ssl_key_handler.cpp (revision 90cd2e1d2e2228b0c575c9a3b6b2dc75eac9eb68)
1 // SPDX-License-Identifier: Apache-2.0
2 // SPDX-FileCopyrightText: Copyright OpenBMC Authors
3 #include "ssl_key_handler.hpp"
4 
5 #include "bmcweb_config.h"
6 
7 #include "forward_unauthorized.hpp"
8 #include "logging.hpp"
9 #include "ossl_random.hpp"
10 #include "sessions.hpp"
11 
12 #include <boost/asio/buffer.hpp>
13 #include <boost/asio/ssl/context.hpp>
14 #include <boost/asio/ssl/verify_mode.hpp>
15 #include <boost/beast/core/file_base.hpp>
16 #include <boost/beast/core/file_posix.hpp>
17 #include <boost/system/error_code.hpp>
18 
19 extern "C"
20 {
21 #include <nghttp2/nghttp2.h>
22 #include <openssl/asn1.h>
23 #include <openssl/bio.h>
24 #include <openssl/ec.h>
25 #include <openssl/err.h>
26 #include <openssl/evp.h>
27 #include <openssl/obj_mac.h>
28 #include <openssl/pem.h>
29 #include <openssl/ssl.h>
30 #include <openssl/tls1.h>
31 #include <openssl/types.h>
32 #include <openssl/x509.h>
33 #include <openssl/x509_vfy.h>
34 #include <openssl/x509v3.h>
35 }
36 
37 #include <bit>
38 #include <cstddef>
39 #include <filesystem>
40 #include <limits>
41 #include <memory>
42 #include <optional>
43 #include <random>
44 #include <string>
45 #include <system_error>
46 #include <utility>
47 
48 namespace ensuressl
49 {
50 
51 static EVP_PKEY* createEcKey();
52 
53 // Mozilla intermediate cipher suites v5.7
54 // Sourced from: https://ssl-config.mozilla.org/guidelines/5.7.json
55 constexpr const char* mozillaIntermediate =
56     "ECDHE-ECDSA-AES128-GCM-SHA256:"
57     "ECDHE-RSA-AES128-GCM-SHA256:"
58     "ECDHE-ECDSA-AES256-GCM-SHA384:"
59     "ECDHE-RSA-AES256-GCM-SHA384:"
60     "ECDHE-ECDSA-CHACHA20-POLY1305:"
61     "ECDHE-RSA-CHACHA20-POLY1305:"
62     "DHE-RSA-AES128-GCM-SHA256:"
63     "DHE-RSA-AES256-GCM-SHA384:"
64     "DHE-RSA-CHACHA20-POLY1305";
65 
66 // Trust chain related errors.`
isTrustChainError(int errnum)67 bool isTrustChainError(int errnum)
68 {
69     return (errnum == X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT) ||
70            (errnum == X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN) ||
71            (errnum == X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY) ||
72            (errnum == X509_V_ERR_CERT_UNTRUSTED) ||
73            (errnum == X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE);
74 }
75 
validateCertificate(X509 * const cert)76 bool validateCertificate(X509* const cert)
77 {
78     // Create an empty X509_STORE structure for certificate validation.
79     X509_STORE* x509Store = X509_STORE_new();
80     if (x509Store == nullptr)
81     {
82         BMCWEB_LOG_ERROR("Error occurred during X509_STORE_new call");
83         return false;
84     }
85 
86     // Load Certificate file into the X509 structure.
87     X509_STORE_CTX* storeCtx = X509_STORE_CTX_new();
88     if (storeCtx == nullptr)
89     {
90         BMCWEB_LOG_ERROR("Error occurred during X509_STORE_CTX_new call");
91         X509_STORE_free(x509Store);
92         return false;
93     }
94 
95     int errCode = X509_STORE_CTX_init(storeCtx, x509Store, cert, nullptr);
96     if (errCode != 1)
97     {
98         BMCWEB_LOG_ERROR("Error occurred during X509_STORE_CTX_init call");
99         X509_STORE_CTX_free(storeCtx);
100         X509_STORE_free(x509Store);
101         return false;
102     }
103 
104     errCode = X509_verify_cert(storeCtx);
105     if (errCode == 1)
106     {
107         BMCWEB_LOG_INFO("Certificate verification is success");
108         X509_STORE_CTX_free(storeCtx);
109         X509_STORE_free(x509Store);
110         return true;
111     }
112     if (errCode == 0)
113     {
114         errCode = X509_STORE_CTX_get_error(storeCtx);
115         X509_STORE_CTX_free(storeCtx);
116         X509_STORE_free(x509Store);
117         if (isTrustChainError(errCode))
118         {
119             BMCWEB_LOG_DEBUG("Ignoring Trust Chain error. Reason: {}",
120                              X509_verify_cert_error_string(errCode));
121             return true;
122         }
123         BMCWEB_LOG_ERROR("Certificate verification failed. Reason: {}",
124                          X509_verify_cert_error_string(errCode));
125         return false;
126     }
127 
128     BMCWEB_LOG_ERROR(
129         "Error occurred during X509_verify_cert call. ErrorCode: {}", errCode);
130     X509_STORE_CTX_free(storeCtx);
131     X509_STORE_free(x509Store);
132     return false;
133 }
134 
verifyOpensslKeyCert(const std::string & filepath)135 std::string verifyOpensslKeyCert(const std::string& filepath)
136 {
137     bool privateKeyValid = false;
138 
139     BMCWEB_LOG_INFO("Checking certs in file {}", filepath);
140     boost::beast::file_posix file;
141     boost::system::error_code ec;
142     file.open(filepath.c_str(), boost::beast::file_mode::read, ec);
143     if (ec)
144     {
145         return "";
146     }
147     bool certValid = false;
148     std::string fileContents;
149     fileContents.resize(static_cast<size_t>(file.size(ec)), '\0');
150     file.read(fileContents.data(), fileContents.size(), ec);
151     if (ec)
152     {
153         BMCWEB_LOG_ERROR("Failed to read file");
154         return "";
155     }
156 
157     BIO* bufio = BIO_new_mem_buf(static_cast<void*>(fileContents.data()),
158                                  static_cast<int>(fileContents.size()));
159     EVP_PKEY* pkey = PEM_read_bio_PrivateKey(bufio, nullptr, nullptr, nullptr);
160     BIO_free(bufio);
161     if (pkey != nullptr)
162     {
163         EVP_PKEY_CTX* pkeyCtx =
164             EVP_PKEY_CTX_new_from_pkey(nullptr, pkey, nullptr);
165 
166         if (pkeyCtx == nullptr)
167         {
168             BMCWEB_LOG_ERROR("Unable to allocate pkeyCtx {}", ERR_get_error());
169         }
170         else if (EVP_PKEY_check(pkeyCtx) == 1)
171         {
172             privateKeyValid = true;
173         }
174         else
175         {
176             BMCWEB_LOG_ERROR("Key not valid error number {}", ERR_get_error());
177         }
178 
179         if (privateKeyValid)
180         {
181             BIO* bufio2 =
182                 BIO_new_mem_buf(static_cast<void*>(fileContents.data()),
183                                 static_cast<int>(fileContents.size()));
184             X509* x509 = PEM_read_bio_X509(bufio2, nullptr, nullptr, nullptr);
185             BIO_free(bufio2);
186             if (x509 == nullptr)
187             {
188                 BMCWEB_LOG_ERROR("error getting x509 cert {}", ERR_get_error());
189             }
190             else
191             {
192                 certValid = validateCertificate(x509);
193                 X509_free(x509);
194             }
195         }
196 
197         EVP_PKEY_CTX_free(pkeyCtx);
198         EVP_PKEY_free(pkey);
199     }
200     if (!certValid)
201     {
202         return "";
203     }
204     return fileContents;
205 }
206 
loadCert(const std::string & filePath)207 X509* loadCert(const std::string& filePath)
208 {
209     BIO* certFileBio = BIO_new_file(filePath.c_str(), "rb");
210     if (certFileBio == nullptr)
211     {
212         BMCWEB_LOG_ERROR("Error occurred during BIO_new_file call, FILE= {}",
213                          filePath);
214         return nullptr;
215     }
216 
217     X509* cert = X509_new();
218     if (cert == nullptr)
219     {
220         BMCWEB_LOG_ERROR("Error occurred during X509_new call, {}",
221                          ERR_get_error());
222         BIO_free(certFileBio);
223         return nullptr;
224     }
225 
226     if (PEM_read_bio_X509(certFileBio, &cert, nullptr, nullptr) == nullptr)
227     {
228         BMCWEB_LOG_ERROR(
229             "Error occurred during PEM_read_bio_X509 call, FILE= {}", filePath);
230 
231         BIO_free(certFileBio);
232         X509_free(cert);
233         return nullptr;
234     }
235     BIO_free(certFileBio);
236     return cert;
237 }
238 
addExt(X509 * cert,int nid,const char * value)239 int addExt(X509* cert, int nid, const char* value)
240 {
241     X509_EXTENSION* ex = nullptr;
242     X509V3_CTX ctx{};
243     X509V3_set_ctx(&ctx, cert, cert, nullptr, nullptr, 0);
244 
245     // NOLINTNEXTLINE(cppcoreguidelines-pro-type-const-cast)
246     ex = X509V3_EXT_conf_nid(nullptr, &ctx, nid, const_cast<char*>(value));
247     if (ex == nullptr)
248     {
249         BMCWEB_LOG_ERROR("Error: In X509V3_EXT_conf_nidn: {}", value);
250         return -1;
251     }
252     X509_add_ext(cert, ex, -1);
253     X509_EXTENSION_free(ex);
254     return 0;
255 }
256 
257 // Writes a certificate to a path, ignoring errors
writeCertificateToFile(const std::string & filepath,const std::string & certificate)258 void writeCertificateToFile(const std::string& filepath,
259                             const std::string& certificate)
260 {
261     boost::system::error_code ec;
262     boost::beast::file_posix file;
263     file.open(filepath.c_str(), boost::beast::file_mode::write, ec);
264     if (!ec)
265     {
266         file.write(certificate.data(), certificate.size(), ec);
267         // ignore result
268     }
269 }
270 
generateSslCertificate(const std::string & cn)271 std::string generateSslCertificate(const std::string& cn)
272 {
273     BMCWEB_LOG_INFO("Generating new keys");
274 
275     std::string buffer;
276     BMCWEB_LOG_INFO("Generating EC key");
277     EVP_PKEY* pPrivKey = createEcKey();
278     if (pPrivKey != nullptr)
279     {
280         BMCWEB_LOG_INFO("Generating x509 Certificates");
281         // Use this code to directly generate a certificate
282         X509* x509 = X509_new();
283         if (x509 != nullptr)
284         {
285             // get a random number from the RNG for the certificate serial
286             // number If this is not random, regenerating certs throws browser
287             // errors
288             bmcweb::OpenSSLGenerator gen;
289             std::uniform_int_distribution<int> dis(
290                 1, std::numeric_limits<int>::max());
291             int serial = dis(gen);
292 
293             ASN1_INTEGER_set(X509_get_serialNumber(x509), serial);
294 
295             // not before this moment
296             X509_gmtime_adj(X509_get_notBefore(x509), 0);
297             // Cert is valid for 10 years
298             X509_gmtime_adj(X509_get_notAfter(x509),
299                             60L * 60L * 24L * 365L * 10L);
300 
301             // set the public key to the key we just generated
302             X509_set_pubkey(x509, pPrivKey);
303 
304             // get the subject name
305             X509_NAME* name = X509_get_subject_name(x509);
306 
307             using x509String = const unsigned char;
308             // NOLINTNEXTLINE(cppcoreguidelines-pro-type-reinterpret-cast)
309             x509String* country = reinterpret_cast<x509String*>("US");
310             // NOLINTNEXTLINE(cppcoreguidelines-pro-type-reinterpret-cast)
311             x509String* company = reinterpret_cast<x509String*>("OpenBMC");
312             // NOLINTNEXTLINE(cppcoreguidelines-pro-type-reinterpret-cast)
313             x509String* cnStr = reinterpret_cast<x509String*>(cn.c_str());
314 
315             X509_NAME_add_entry_by_txt(name, "C", MBSTRING_ASC, country, -1, -1,
316                                        0);
317             X509_NAME_add_entry_by_txt(name, "O", MBSTRING_ASC, company, -1, -1,
318                                        0);
319             X509_NAME_add_entry_by_txt(name, "CN", MBSTRING_ASC, cnStr, -1, -1,
320                                        0);
321             // set the CSR options
322             X509_set_issuer_name(x509, name);
323 
324             X509_set_version(x509, 2);
325             addExt(x509, NID_basic_constraints, ("critical,CA:TRUE"));
326             addExt(x509, NID_subject_alt_name, ("DNS:" + cn).c_str());
327             addExt(x509, NID_subject_key_identifier, ("hash"));
328             addExt(x509, NID_authority_key_identifier, ("keyid"));
329             addExt(x509, NID_key_usage, ("digitalSignature, keyEncipherment"));
330             addExt(x509, NID_ext_key_usage, ("serverAuth"));
331             addExt(x509, NID_netscape_comment, (x509Comment));
332 
333             // Sign the certificate with our private key
334             X509_sign(x509, pPrivKey, EVP_sha256());
335 
336             BIO* bufio = BIO_new(BIO_s_mem());
337 
338             int pkeyRet = PEM_write_bio_PrivateKey(
339                 bufio, pPrivKey, nullptr, nullptr, 0, nullptr, nullptr);
340             if (pkeyRet <= 0)
341             {
342                 BMCWEB_LOG_ERROR(
343                     "Failed to write pkey with code {}.  Ignoring.", pkeyRet);
344             }
345 
346             char* data = nullptr;
347             long int dataLen = BIO_get_mem_data(bufio, &data);
348             buffer += std::string_view(data, static_cast<size_t>(dataLen));
349             BIO_free(bufio);
350 
351             bufio = BIO_new(BIO_s_mem());
352             pkeyRet = PEM_write_bio_X509(bufio, x509);
353             if (pkeyRet <= 0)
354             {
355                 BMCWEB_LOG_ERROR(
356                     "Failed to write X509 with code {}.  Ignoring.", pkeyRet);
357             }
358             dataLen = BIO_get_mem_data(bufio, &data);
359             buffer += std::string_view(data, static_cast<size_t>(dataLen));
360 
361             BIO_free(bufio);
362             BMCWEB_LOG_INFO("Cert size is {}", buffer.size());
363             X509_free(x509);
364         }
365 
366         EVP_PKEY_free(pPrivKey);
367         pPrivKey = nullptr;
368     }
369 
370     // cleanup_openssl();
371     return buffer;
372 }
373 
createEcKey()374 EVP_PKEY* createEcKey()
375 {
376     EVP_PKEY* pKey = nullptr;
377 
378     // Create context for curve parameter generation.
379     std::unique_ptr<EVP_PKEY_CTX, decltype(&::EVP_PKEY_CTX_free)> ctx{
380         EVP_PKEY_CTX_new_id(EVP_PKEY_EC, nullptr), &::EVP_PKEY_CTX_free};
381     if (!ctx)
382     {
383         return nullptr;
384     }
385 
386     // Set up curve parameters.
387     EVP_PKEY* params = nullptr;
388     if ((EVP_PKEY_paramgen_init(ctx.get()) <= 0) ||
389         (EVP_PKEY_CTX_set_ec_param_enc(ctx.get(), OPENSSL_EC_NAMED_CURVE) <=
390          0) ||
391         (EVP_PKEY_CTX_set_ec_paramgen_curve_nid(ctx.get(), NID_secp384r1) <=
392          0) ||
393         (EVP_PKEY_paramgen(ctx.get(), &params) <= 0))
394     {
395         return nullptr;
396     }
397 
398     // Set up RAII holder for params.
399     std::unique_ptr<EVP_PKEY, decltype(&::EVP_PKEY_free)> pparams{
400         params, &::EVP_PKEY_free};
401 
402     // Set new context for key generation, using curve parameters.
403     ctx.reset(EVP_PKEY_CTX_new_from_pkey(nullptr, params, nullptr));
404     if (!ctx || (EVP_PKEY_keygen_init(ctx.get()) <= 0))
405     {
406         return nullptr;
407     }
408 
409     // Generate key.
410     if (EVP_PKEY_keygen(ctx.get(), &pKey) <= 0)
411     {
412         return nullptr;
413     }
414 
415     return pKey;
416 }
417 
ensureOpensslKeyPresentAndValid(const std::string & filepath)418 std::string ensureOpensslKeyPresentAndValid(const std::string& filepath)
419 {
420     std::string cert = verifyOpensslKeyCert(filepath);
421 
422     if (cert.empty())
423     {
424         BMCWEB_LOG_WARNING("Error in verifying signature, regenerating");
425         cert = generateSslCertificate("testhost");
426         if (cert.empty())
427         {
428             BMCWEB_LOG_ERROR("Failed to generate cert");
429         }
430         else
431         {
432             writeCertificateToFile(filepath, cert);
433         }
434     }
435     return cert;
436 }
437 
ensureCertificate()438 static std::string ensureCertificate()
439 {
440     namespace fs = std::filesystem;
441     // Cleanup older certificate file existing in the system
442     fs::path oldcertPath = fs::path("/home/root/server.pem");
443     std::error_code ec;
444     fs::remove(oldcertPath, ec);
445     // Ignore failure to remove;  File might not exist.
446 
447     fs::path certPath = "/etc/ssl/certs/https/";
448     // if path does not exist create the path so that
449     // self signed certificate can be created in the
450     // path
451     fs::path certFile = certPath / "server.pem";
452 
453     if (!fs::exists(certPath, ec))
454     {
455         fs::create_directories(certPath, ec);
456     }
457     BMCWEB_LOG_INFO("Building SSL Context file= {}", certFile.string());
458     std::string sslPemFile(certFile);
459     return ensuressl::ensureOpensslKeyPresentAndValid(sslPemFile);
460 }
461 
nextProtoCallback(SSL *,const unsigned char ** data,unsigned int * len,void *)462 static int nextProtoCallback(SSL* /*unused*/, const unsigned char** data,
463                              unsigned int* len, void* /*unused*/)
464 {
465     // First byte is the length.
466     constexpr std::string_view h2 = "\x02h2";
467     *data = std::bit_cast<const unsigned char*>(h2.data());
468     *len = static_cast<unsigned int>(h2.size());
469     return SSL_TLSEXT_ERR_OK;
470 }
471 
alpnSelectProtoCallback(SSL *,const unsigned char ** out,unsigned char * outlen,const unsigned char * in,unsigned int inlen,void *)472 static int alpnSelectProtoCallback(
473     SSL* /*unused*/, const unsigned char** out, unsigned char* outlen,
474     const unsigned char* in, unsigned int inlen, void* /*unused*/)
475 {
476     int rv = nghttp2_select_alpn(out, outlen, in, inlen);
477     if (rv == -1)
478     {
479         return SSL_TLSEXT_ERR_NOACK;
480     }
481     if (rv == 1)
482     {
483         BMCWEB_LOG_DEBUG("Selected HTTP2");
484     }
485     return SSL_TLSEXT_ERR_OK;
486 }
487 
getSslContext(boost::asio::ssl::context & mSslContext,const std::string & sslPemFile)488 static bool getSslContext(boost::asio::ssl::context& mSslContext,
489                           const std::string& sslPemFile)
490 {
491     mSslContext.set_options(
492         boost::asio::ssl::context::default_workarounds |
493         boost::asio::ssl::context::no_sslv2 |
494         boost::asio::ssl::context::no_sslv3 |
495         boost::asio::ssl::context::single_dh_use |
496         boost::asio::ssl::context::no_tlsv1 |
497         boost::asio::ssl::context::no_tlsv1_1);
498 
499     BMCWEB_LOG_DEBUG("Using default TrustStore location: {}", trustStorePath);
500     mSslContext.add_verify_path(trustStorePath);
501 
502     if (!sslPemFile.empty())
503     {
504         boost::system::error_code ec;
505 
506         boost::asio::const_buffer buf(sslPemFile.data(), sslPemFile.size());
507         mSslContext.use_certificate_chain(buf, ec);
508         if (ec)
509         {
510             return false;
511         }
512         mSslContext.use_private_key(buf, boost::asio::ssl::context::pem, ec);
513         if (ec)
514         {
515             BMCWEB_LOG_CRITICAL("Failed to open ssl pkey");
516             return false;
517         }
518     }
519 
520     // Set up EC curves to auto (boost asio doesn't have a method for this)
521     // There is a pull request to add this.  Once this is included in an asio
522     // drop, use the right way
523     // http://stackoverflow.com/questions/18929049/boost-asio-with-ecdsa-certificate-issue
524     if (SSL_CTX_set_ecdh_auto(mSslContext.native_handle(), 1) != 1)
525     {}
526 
527     if (SSL_CTX_set_cipher_list(mSslContext.native_handle(),
528                                 mozillaIntermediate) != 1)
529     {
530         BMCWEB_LOG_ERROR("Error setting cipher list");
531         return false;
532     }
533     return true;
534 }
535 
getSslServerContext()536 std::shared_ptr<boost::asio::ssl::context> getSslServerContext()
537 {
538     boost::asio::ssl::context sslCtx(boost::asio::ssl::context::tls_server);
539 
540     auto certFile = ensureCertificate();
541     if (!getSslContext(sslCtx, certFile))
542     {
543         BMCWEB_LOG_CRITICAL("Couldn't get server context");
544         return nullptr;
545     }
546     const persistent_data::AuthConfigMethods& c =
547         persistent_data::SessionStore::getInstance().getAuthMethodsConfig();
548 
549     boost::asio::ssl::verify_mode mode = boost::asio::ssl::verify_none;
550     if (c.tlsStrict)
551     {
552         BMCWEB_LOG_DEBUG("Setting verify peer and fail if no peer cert");
553         mode |= boost::asio::ssl::verify_peer;
554         mode |= boost::asio::ssl::verify_fail_if_no_peer_cert;
555     }
556     else if (!forward_unauthorized::hasWebuiRoute)
557     {
558         // This is a HACK
559         // If the webui is installed, and TLSSTrict is false, we don't want to
560         // force the mtls popup to occur, which would happen if we requested a
561         // client cert by setting verify_peer. But, if the webui isn't
562         // installed, we'd like clients to be able to optionally log in with
563         // MTLS, which won't happen if we don't expose the MTLS client cert
564         // request.  So, in this case detect if the webui is installed, and
565         // only request peer authentication if it's not present.
566         // This will likely need revisited in the future.
567         BMCWEB_LOG_DEBUG("Setting verify peer only");
568         mode |= boost::asio::ssl::verify_peer;
569     }
570 
571     boost::system::error_code ec;
572     sslCtx.set_verify_mode(mode, ec);
573     if (ec)
574     {
575         BMCWEB_LOG_DEBUG("Failed to set verify mode {}", ec.message());
576         return nullptr;
577     }
578 
579     SSL_CTX_set_options(sslCtx.native_handle(), SSL_OP_NO_RENEGOTIATION);
580 
581     if constexpr (BMCWEB_EXPERIMENTAL_HTTP2)
582     {
583         SSL_CTX_set_next_protos_advertised_cb(sslCtx.native_handle(),
584                                               nextProtoCallback, nullptr);
585 
586         SSL_CTX_set_alpn_select_cb(sslCtx.native_handle(),
587                                    alpnSelectProtoCallback, nullptr);
588     }
589 
590     return std::make_shared<boost::asio::ssl::context>(std::move(sslCtx));
591 }
592 
getSSLClientContext(VerifyCertificate verifyCertificate)593 std::optional<boost::asio::ssl::context> getSSLClientContext(
594     VerifyCertificate verifyCertificate)
595 {
596     namespace fs = std::filesystem;
597 
598     boost::asio::ssl::context sslCtx(boost::asio::ssl::context::tls_client);
599 
600     // NOTE, this path is temporary;  In the future it will need to change to
601     // be set per subscription.  Do not rely on this.
602     fs::path certPath = "/etc/ssl/certs/https/client.pem";
603     std::string cert = verifyOpensslKeyCert(certPath);
604 
605     if (!getSslContext(sslCtx, cert))
606     {
607         return std::nullopt;
608     }
609 
610     // Add a directory containing certificate authority files to be used
611     // for performing verification.
612     boost::system::error_code ec;
613     sslCtx.set_default_verify_paths(ec);
614     if (ec)
615     {
616         BMCWEB_LOG_ERROR("SSL context set_default_verify failed");
617         return std::nullopt;
618     }
619 
620     int mode = boost::asio::ssl::verify_peer;
621     if (verifyCertificate == VerifyCertificate::NoVerify)
622     {
623         mode = boost::asio::ssl::verify_none;
624     }
625 
626     // Verify the remote server's certificate
627     sslCtx.set_verify_mode(mode, ec);
628     if (ec)
629     {
630         BMCWEB_LOG_ERROR("SSL context set_verify_mode failed");
631         return std::nullopt;
632     }
633 
634     if (SSL_CTX_set_cipher_list(sslCtx.native_handle(), mozillaIntermediate) !=
635         1)
636     {
637         BMCWEB_LOG_ERROR("SSL_CTX_set_cipher_list failed");
638         return std::nullopt;
639     }
640 
641     return {std::move(sslCtx)};
642 }
643 
644 } // namespace ensuressl
645