SERVER-32748 Split ssl_manager.cpp into openssl specific and general components.

1 files changed, 1524 insertions, 0 deletions

diff --git a/src/mongo/util/net/ssl_manager_openssl.cpp b/src/mongo/util/net/ssl_manager_openssl.cpp
new file mode 100644
index 00000000000..c9e0b44ea49
--- /dev/null
+++ b/src/mongo/util/net/ssl_manager_openssl.cpp
@@ -0,0 +1,1524 @@
+/**
+ * Copyright (C) 2018 MongoDB Inc.
+ *
+ * This program is free software: you can redistribute it and/or  modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * As a special exception, the copyright holders give permission to link the
+ * code of portions of this program with the OpenSSL library under certain
+ * conditions as described in each individual source file and distribute
+ * linked combinations including the program with the OpenSSL library. You
+ * must comply with the GNU Affero General Public License in all respects
+ * for all of the code used other than as permitted herein. If you modify
+ * file(s) with this exception, you may extend this exception to your
+ * version of the file(s), but you are not obligated to do so. If you do not
+ * wish to do so, delete this exception statement from your version. If you
+ * delete this exception statement from all source files in the program,
+ * then also delete it in the license file.
+ */
+
+#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kNetwork
+
+#include "mongo/platform/basic.h"
+
+#include "mongo/util/net/ssl_manager.h"
+
+#include <boost/algorithm/string.hpp>
+#include <boost/date_time/posix_time/posix_time.hpp>
+#include <fstream>
+#include <iostream>
+#include <sstream>
+#include <stack>
+#include <string>
+#include <vector>
+
+#include "mongo/base/init.h"
+#include "mongo/bson/bsonobjbuilder.h"
+#include "mongo/config.h"
+#include "mongo/db/server_parameters.h"
+#include "mongo/platform/atomic_word.h"
+#include "mongo/stdx/memory.h"
+#include "mongo/transport/session.h"
+#include "mongo/util/concurrency/mutex.h"
+#include "mongo/util/debug_util.h"
+#include "mongo/util/exit.h"
+#include "mongo/util/log.h"
+#include "mongo/util/mongoutils/str.h"
+#include "mongo/util/net/private/ssl_expiration.h"
+#include "mongo/util/net/sock.h"
+#include "mongo/util/net/socket_exception.h"
+#include "mongo/util/net/ssl_options.h"
+#include "mongo/util/net/ssl_types.h"
+#include "mongo/util/scopeguard.h"
+#include "mongo/util/text.h"
+
+#include <openssl/asn1.h>
+#include <openssl/asn1t.h>
+#include <openssl/evp.h>
+#include <openssl/x509_vfy.h>
+#include <openssl/x509v3.h>
+#if defined(_WIN32)
+#include <wincrypt.h>
+#elif defined(__APPLE__)
+#include <Security/Security.h>
+#endif
+
+namespace mongo {
+
+namespace {
+
+std::string removeFQDNRoot(std::string name) {
+    if (name.back() == '.') {
+        name.pop_back();
+    }
+    return name;
+};
+
+
+// Because the hostname having a slash is used by `mongo::SockAddr` to determine if a hostname is a
+// Unix Domain Socket endpoint, this function uses the same logic.  (See
+// `mongo::SockAddr::Sockaddr(StringData, int, sa_family_t)`).  A user explicitly specifying a Unix
+// Domain Socket in the present working directory, through a code path which supplies `sa_family_t`
+// as `AF_UNIX` will cause this code to lie.  This will, in turn, cause the
+// `SSLManager::parseAndValidatePeerCertificate` code to believe a socket is a host, which will then
+// cause a connection failure if and only if that domain socket also has a certificate for SSL and
+// the connection is an SSL connection.
+bool isUnixDomainSocket(const std::string& hostname) {
+    return end(hostname) != std::find(begin(hostname), end(hostname), '/');
+}
+
+// If the underlying SSL supports auto-configuration of ECDH parameters, this function will select
+// it, otherwise this function will do nothing.
+void setECDHModeAuto(SSL_CTX* const ctx) {
+#ifdef MONGO_CONFIG_HAVE_SSL_SET_ECDH_AUTO
+    ::SSL_CTX_set_ecdh_auto(ctx, true);
+#endif
+    std::ignore = ctx;
+}
+
+struct DHFreer {
+    void operator()(DH* const dh) noexcept {
+        if (dh) {
+            ::DH_free(dh);
+        }
+    }
+};
+using UniqueDHParams = std::unique_ptr<DH, DHFreer>;
+
+struct BIOFree {
+    void operator()(BIO* const p) noexcept {
+        // Assumes that BIO_free succeeds.
+        if (p) {
+            ::BIO_free(p);
+        }
+    }
+};
+using UniqueBIO = std::unique_ptr<BIO, BIOFree>;
+
+UniqueBIO makeUniqueMemBio(std::vector<std::uint8_t>& v) {
+    UniqueBIO rv(::BIO_new_mem_buf(v.data(), v.size()));
+    if (!rv) {
+        class ssl_bad_alloc : public std::bad_alloc {
+        private:
+            std::string message;
+
+        public:
+            explicit ssl_bad_alloc(std::string m) : message(std::move(m)) {}
+
+            const char* what() const noexcept override {
+                return message.c_str();
+            }
+        };
+        throw ssl_bad_alloc(str::stream()
+                            << "Error allocating SSL BIO: "
+                            << SSLManagerInterface::getSSLErrorMessage(ERR_get_error()));
+    }
+    return rv;
+}
+
+// Old copies of OpenSSL will not have constants to disable protocols they don't support.
+// Define them to values we can OR together safely to generically disable these protocols across
+// all versions of OpenSSL.
+#ifndef SSL_OP_NO_TLSv1_1
+#define SSL_OP_NO_TLSv1_1 0
+#endif
+#ifndef SSL_OP_NO_TLSv1_2
+#define SSL_OP_NO_TLSv1_2 0
+#endif
+
+// clang-format off
+#ifndef MONGO_CONFIG_HAVE_ASN1_ANY_DEFINITIONS
+// Copies of OpenSSL before 1.0.0 do not have ASN1_SEQUENCE_ANY, ASN1_SET_ANY, or the helper
+// functions which let us deserialize these objects. We must polyfill the definitions to interact
+// with ASN1 objects so stored.
+typedef STACK_OF(ASN1_TYPE) ASN1_SEQUENCE_ANY;
+
+ASN1_ITEM_TEMPLATE(ASN1_SEQUENCE_ANY) =
+    ASN1_EX_TEMPLATE_TYPE(ASN1_TFLG_SEQUENCE_OF, 0, ASN1_SEQUENCE_ANY, ASN1_ANY)
+ASN1_ITEM_TEMPLATE_END(ASN1_SEQUENCE_ANY)
+
+ASN1_ITEM_TEMPLATE(ASN1_SET_ANY) =
+    ASN1_EX_TEMPLATE_TYPE(ASN1_TFLG_SET_OF, 0, ASN1_SET_ANY, ASN1_ANY)
+ASN1_ITEM_TEMPLATE_END(ASN1_SET_ANY)
+
+IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(ASN1_SEQUENCE_ANY, ASN1_SEQUENCE_ANY,
+                                            ASN1_SEQUENCE_ANY)
+IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(ASN1_SEQUENCE_ANY, ASN1_SET_ANY, ASN1_SET_ANY)
+; // clang format needs to see a semicolon or it will start formatting unrelated code
+#endif // MONGO_CONFIG_NEEDS_ASN1_ANY_DEFINITIONS
+// clang-format on
+
+#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
+// Copies of OpenSSL after 1.1.0 define new functions for interaction with
+// X509 structure. We must polyfill used definitions to interact with older
+// OpenSSL versions.
+const STACK_OF(X509_EXTENSION) * X509_get0_extensions(const X509* peerCert) {
+    return peerCert->cert_info->extensions;
+}
+#endif
+
+/**
+ * Multithreaded Support for SSL.
+ *
+ * In order to allow OpenSSL to work in a multithreaded environment, you
+ * may need to provide some callbacks for it to use for locking. The following code
+ * sets up a vector of mutexes and provides a thread unique ID number.
+ * The so-called SSLThreadInfo class encapsulates most of the logic required for
+ * OpenSSL multithreaded support.
+ *
+ * OpenSSL before version 1.1.0 requires applications provide a callback which emits a thread
+ * identifier. This ID is used to store thread specific ERR information. When a thread is
+ * terminated, it must call ERR_remove_state or ERR_remove_thread_state. These functions may
+ * themselves invoke the application provided callback. These IDs are stored in a hashtable with
+ * a questionable hash function. They must be uniformly distributed to prevent collisions.
+ */
+class SSLThreadInfo {
+public:
+    static unsigned long getID() {
+        struct CallErrRemoveState {
+            explicit CallErrRemoveState(ThreadIDManager& manager, unsigned long id)
+                : _manager(manager), id(id) {}
+
+            ~CallErrRemoveState() {
+                ERR_remove_state(0);
+                _manager.releaseID(id);
+            };
+
+            ThreadIDManager& _manager;
+            unsigned long id;
+        };
+
+        // NOTE: This logic is fully intentional. Because ERR_remove_state (called within
+        // the destructor of the kRemoveStateFromThread object) re-enters this function,
+        // we must have a two phase protection, otherwise we would access a thread local
+        // during its destruction.
+        static thread_local boost::optional<CallErrRemoveState> threadLocalState;
+        if (!threadLocalState) {
+            threadLocalState.emplace(_idManager, _idManager.reserveID());
+        }
+
+        return threadLocalState->id;
+    }
+
+    static void lockingCallback(int mode, int type, const char* file, int line) {
+        if (mode & CRYPTO_LOCK) {
+            _mutex[type]->lock();
+        } else {
+            _mutex[type]->unlock();
+        }
+    }
+
+    static void init() {
+        CRYPTO_set_id_callback(&SSLThreadInfo::getID);
+        CRYPTO_set_locking_callback(&SSLThreadInfo::lockingCallback);
+
+        while ((int)_mutex.size() < CRYPTO_num_locks()) {
+            _mutex.emplace_back(stdx::make_unique<stdx::recursive_mutex>());
+        }
+    }
+
+private:
+    SSLThreadInfo() = delete;
+
+    // Note: see SERVER-8734 for why we are using a recursive mutex here.
+    // Once the deadlock fix in OpenSSL is incorporated into most distros of
+    // Linux, this can be changed back to a nonrecursive mutex.
+    static std::vector<std::unique_ptr<stdx::recursive_mutex>> _mutex;
+
+    class ThreadIDManager {
+    public:
+        unsigned long reserveID() {
+            stdx::unique_lock<stdx::mutex> lock(_idMutex);
+            if (!_idLast.empty()) {
+                unsigned long ret = _idLast.top();
+                _idLast.pop();
+                return ret;
+            }
+            return ++_idNext;
+        }
+
+        void releaseID(unsigned long id) {
+            stdx::unique_lock<stdx::mutex> lock(_idMutex);
+            _idLast.push(id);
+        }
+
+    private:
+        // Machinery for producing IDs that are unique for the life of a thread.
+        stdx::mutex _idMutex;       // Protects _idNext and _idLast.
+        unsigned long _idNext = 0;  // Stores the next thread ID to use, if none already allocated.
+        std::stack<unsigned long, std::vector<unsigned long>>
+            _idLast;  // Stores old thread IDs, for reuse.
+    };
+    static ThreadIDManager _idManager;
+};
+std::vector<std::unique_ptr<stdx::recursive_mutex>> SSLThreadInfo::_mutex;
+SSLThreadInfo::ThreadIDManager SSLThreadInfo::_idManager;
+
+namespace {
+// We only want to free SSL_CTX objects if they have been populated. OpenSSL seems to perform this
+// check before freeing them, but because it does not document this, we should protect ourselves.
+void free_ssl_context(SSL_CTX* ctx) {
+    if (ctx != nullptr) {
+        SSL_CTX_free(ctx);
+    }
+}
+}  // namespace
+
+////////////////////////////////////////////////////////////////
+
+SimpleMutex sslManagerMtx;
+SSLManagerInterface* theSSLManager = NULL;
+using UniqueSSLContext = std::unique_ptr<SSL_CTX, decltype(&free_ssl_context)>;
+static const int BUFFER_SIZE = 8 * 1024;
+static const int DATE_LEN = 128;
+
+class SSLManager : public SSLManagerInterface {
+public:
+    explicit SSLManager(const SSLParams& params, bool isServer);
+
+    /**
+     * Initializes an OpenSSL context according to the provided settings. Only settings which are
+     * acceptable on non-blocking connections are set.
+     */
+    Status initSSLContext(SSL_CTX* context,
+                          const SSLParams& params,
+                          ConnectionDirection direction) final;
+
+    virtual SSLConnection* connect(Socket* socket);
+
+    virtual SSLConnection* accept(Socket* socket, const char* initialBytes, int len);
+
+    virtual SSLPeerInfo parseAndValidatePeerCertificateDeprecated(const SSLConnection* conn,
+                                                                  const std::string& remoteHost);
+
+    StatusWith<boost::optional<SSLPeerInfo>> parseAndValidatePeerCertificate(
+        SSL* conn, const std::string& remoteHost) final;
+
+    virtual const SSLConfiguration& getSSLConfiguration() const {
+        return _sslConfiguration;
+    }
+
+    virtual int SSL_read(SSLConnection* conn, void* buf, int num);
+
+    virtual int SSL_write(SSLConnection* conn, const void* buf, int num);
+
+    virtual unsigned long ERR_get_error();
+
+    virtual char* ERR_error_string(unsigned long e, char* buf);
+
+    virtual int SSL_get_error(const SSLConnection* conn, int ret);
+
+    virtual int SSL_shutdown(SSLConnection* conn);
+
+    virtual void SSL_free(SSLConnection* conn);
+
+private:
+    const int _rolesNid = OBJ_create(mongodbRolesOID.identifier.c_str(),
+                                     mongodbRolesOID.shortDescription.c_str(),
+                                     mongodbRolesOID.longDescription.c_str());
+    UniqueSSLContext _serverContext;  // SSL context for incoming connections
+    UniqueSSLContext _clientContext;  // SSL context for outgoing connections
+    bool _weakValidation;
+    bool _allowInvalidCertificates;
+    bool _allowInvalidHostnames;
+    SSLConfiguration _sslConfiguration;
+
+    /**
+     * creates an SSL object to be used for this file descriptor.
+     * caller must SSL_free it.
+     */
+    SSL* _secure(SSL_CTX* context, int fd);
+
+    /**
+     * Given an error code from an SSL-type IO function, logs an
+     * appropriate message and throws a NetworkException.
+     */
+    MONGO_COMPILER_NORETURN void _handleSSLError(int code, int ret);
+
+    /*
+     * Init the SSL context using parameters provided in params. This SSL context will
+     * be configured for blocking send/receive.
+     */
+    bool _initSynchronousSSLContext(UniqueSSLContext* context,
+                                    const SSLParams& params,
+                                    ConnectionDirection direction);
+
+    /*
+     * Converts time from OpenSSL return value to unsigned long long
+     * representing the milliseconds since the epoch.
+     */
+    unsigned long long _convertASN1ToMillis(ASN1_TIME* t);
+
+    /*
+     * Parse and store x509 subject name from the PEM keyfile.
+     * For server instances check that PEM certificate is not expired
+     * and extract server certificate notAfter date.
+     * @param keyFile referencing the PEM file to be read.
+     * @param subjectName as a pointer to the subject name variable being set.
+     * @param serverNotAfter a Date_t object pointer that is valued if the
+     * date is to be checked (as for a server certificate) and null otherwise.
+     * @return bool showing if the function was successful.
+     */
+    bool _parseAndValidateCertificate(const std::string& keyFile,
+                                      const std::string& keyPassword,
+                                      std::string* subjectName,
+                                      Date_t* serverNotAfter);
+
+
+    StatusWith<stdx::unordered_set<RoleName>> _parsePeerRoles(X509* peerCert) const;
+
+    /** @return true if was successful, otherwise false */
+    bool _setupPEM(SSL_CTX* context, const std::string& keyFile, const std::string& password);
+
+    /*
+     * Set up an SSL context for certificate validation by loading a CA
+     */
+    Status _setupCA(SSL_CTX* context, const std::string& caFile);
+
+    /*
+     * Set up an SSL context for certificate validation by loading the system's CA store
+     */
+    Status _setupSystemCA(SSL_CTX* context);
+
+    /*
+     * Import a certificate revocation list into an SSL context
+     * for use with validating certificates
+     */
+    bool _setupCRL(SSL_CTX* context, const std::string& crlFile);
+
+    /*
+     * sub function for checking the result of an SSL operation
+     */
+    bool _doneWithSSLOp(SSLConnection* conn, int status);
+
+    /*
+     * Send and receive network data
+     */
+    void _flushNetworkBIO(SSLConnection* conn);
+
+    /**
+     * Callbacks for SSL functions.
+     */
+    static int password_cb(char* buf, int num, int rwflag, void* userdata);
+    static int verify_cb(int ok, X509_STORE_CTX* ctx);
+};
+
+void setupFIPS() {
+// Turn on FIPS mode if requested, OPENSSL_FIPS must be defined by the OpenSSL headers
+#if defined(MONGO_CONFIG_HAVE_FIPS_MODE_SET)
+    int status = FIPS_mode_set(1);
+    if (!status) {
+        severe() << "can't activate FIPS mode: "
+                 << SSLManagerInterface::getSSLErrorMessage(ERR_get_error());
+        fassertFailedNoTrace(16703);
+    }
+    log() << "FIPS 140-2 mode activated";
+#else
+    severe() << "this version of mongodb was not compiled with FIPS support";
+    fassertFailedNoTrace(17089);
+#endif
+}
+
+}  // namespace
+
+// Global variable indicating if this is a server or a client instance
+bool isSSLServer = false;
+
+
+MONGO_INITIALIZER(SetupOpenSSL)(InitializerContext*) {
+    SSL_library_init();
+    SSL_load_error_strings();
+    ERR_load_crypto_strings();
+
+    if (sslGlobalParams.sslFIPSMode) {
+        setupFIPS();
+    }
+
+    // Add all digests and ciphers to OpenSSL's internal table
+    // so that encryption/decryption is backwards compatible
+    OpenSSL_add_all_algorithms();
+
+    // Setup OpenSSL multithreading callbacks and mutexes
+    SSLThreadInfo::init();
+
+    return Status::OK();
+}
+
+MONGO_INITIALIZER_WITH_PREREQUISITES(SSLManager, ("SetupOpenSSL"))(InitializerContext*) {
+    stdx::lock_guard<SimpleMutex> lck(sslManagerMtx);
+    if (!isSSLServer || (sslGlobalParams.sslMode.load() != SSLParams::SSLMode_disabled)) {
+        theSSLManager = new SSLManager(sslGlobalParams, isSSLServer);
+    }
+    return Status::OK();
+}
+
+std::unique_ptr<SSLManagerInterface> SSLManagerInterface::create(const SSLParams& params,
+                                                                 bool isServer) {
+    return stdx::make_unique<SSLManager>(params, isServer);
+}
+
+SSLManagerInterface* getSSLManager() {
+    stdx::lock_guard<SimpleMutex> lck(sslManagerMtx);
+    if (theSSLManager)
+        return theSSLManager;
+    return NULL;
+}
+
+std::string getCertificateSubjectName(X509* cert) {
+    std::string result;
+
+    BIO* out = BIO_new(BIO_s_mem());
+    uassert(16884, "unable to allocate BIO memory", NULL != out);
+    ON_BLOCK_EXIT(BIO_free, out);
+
+    if (X509_NAME_print_ex(out, X509_get_subject_name(cert), 0, XN_FLAG_RFC2253) >= 0) {
+        if (BIO_number_written(out) > 0) {
+            result.resize(BIO_number_written(out));
+            BIO_read(out, &result[0], result.size());
+        }
+    } else {
+        log() << "failed to convert subject name to RFC2253 format";
+    }
+
+    return result;
+}
+
+SSLConnection::SSLConnection(SSL_CTX* context, Socket* sock, const char* initialBytes, int len)
+    : socket(sock) {
+    ssl = SSL_new(context);
+
+    std::string sslErr =
+        NULL != getSSLManager() ? getSSLManager()->getSSLErrorMessage(ERR_get_error()) : "";
+    massert(15861, "Error creating new SSL object " + sslErr, ssl);
+
+    BIO_new_bio_pair(&internalBIO, BUFFER_SIZE, &networkBIO, BUFFER_SIZE);
+    SSL_set_bio(ssl, internalBIO, internalBIO);
+
+    if (len > 0) {
+        int toBIO = BIO_write(networkBIO, initialBytes, len);
+        if (toBIO != len) {
+            LOG(3) << "Failed to write initial network data to the SSL BIO layer";
+            throwSocketError(SocketErrorKind::RECV_ERROR, socket->remoteString());
+        }
+    }
+}
+
+SSLConnection::~SSLConnection() {
+    if (ssl) {  // The internalBIO is automatically freed as part of SSL_free
+        SSL_free(ssl);
+    }
+    if (networkBIO) {
+        BIO_free(networkBIO);
+    }
+}
+
+SSLManager::SSLManager(const SSLParams& params, bool isServer)
+    : _serverContext(nullptr, free_ssl_context),
+      _clientContext(nullptr, free_ssl_context),
+      _weakValidation(params.sslWeakCertificateValidation),
+      _allowInvalidCertificates(params.sslAllowInvalidCertificates),
+      _allowInvalidHostnames(params.sslAllowInvalidHostnames) {
+    if (!_initSynchronousSSLContext(&_clientContext, params, ConnectionDirection::kOutgoing)) {
+        uasserted(16768, "ssl initialization problem");
+    }
+
+    // pick the certificate for use in outgoing connections,
+    std::string clientPEM, clientPassword;
+    if (!isServer || params.sslClusterFile.empty()) {
+        // We are either a client, or a server without a cluster key,
+        // so use the PEM key file, if specified
+        clientPEM = params.sslPEMKeyFile;
+        clientPassword = params.sslPEMKeyPassword;
+    } else {
+        // We are a server with a cluster key, so use the cluster key file
+        clientPEM = params.sslClusterFile;
+        clientPassword = params.sslClusterPassword;
+    }
+
+    if (!clientPEM.empty()) {
+        if (!_parseAndValidateCertificate(
+                clientPEM, clientPassword, &_sslConfiguration.clientSubjectName, NULL)) {
+            uasserted(16941, "ssl initialization problem");
+        }
+    }
+    // SSL server specific initialization
+    if (isServer) {
+        if (!_initSynchronousSSLContext(&_serverContext, params, ConnectionDirection::kIncoming)) {
+            uasserted(16562, "ssl initialization problem");
+        }
+
+        if (!_parseAndValidateCertificate(params.sslPEMKeyFile,
+                                          params.sslPEMKeyPassword,
+                                          &_sslConfiguration.serverSubjectName,
+                                          &_sslConfiguration.serverCertificateExpirationDate)) {
+            uasserted(16942, "ssl initialization problem");
+        }
+
+        static CertificateExpirationMonitor task =
+            CertificateExpirationMonitor(_sslConfiguration.serverCertificateExpirationDate);
+    }
+}
+
+int SSLManager::password_cb(char* buf, int num, int rwflag, void* userdata) {
+    // Unless OpenSSL misbehaves, num should always be positive
+    fassert(17314, num > 0);
+    invariant(userdata);
+    auto pw = static_cast<const std::string*>(userdata);
+
+    const size_t copied = pw->copy(buf, num - 1);
+    buf[copied] = '\0';
+    return copied;
+}
+
+int SSLManager::verify_cb(int ok, X509_STORE_CTX* ctx) {
+    return 1;  // always succeed; we will catch the error in our get_verify_result() call
+}
+
+int SSLManager::SSL_read(SSLConnection* conn, void* buf, int num) {
+    int status;
+    do {
+        status = ::SSL_read(conn->ssl, buf, num);
+    } while (!_doneWithSSLOp(conn, status));
+
+    if (status <= 0)
+        _handleSSLError(SSL_get_error(conn, status), status);
+    return status;
+}
+
+int SSLManager::SSL_write(SSLConnection* conn, const void* buf, int num) {
+    int status;
+    do {
+        status = ::SSL_write(conn->ssl, buf, num);
+    } while (!_doneWithSSLOp(conn, status));
+
+    if (status <= 0)
+        _handleSSLError(SSL_get_error(conn, status), status);
+    return status;
+}
+
+unsigned long SSLManager::ERR_get_error() {
+    return ::ERR_get_error();
+}
+
+char* SSLManager::ERR_error_string(unsigned long e, char* buf) {
+    return ::ERR_error_string(e, buf);
+}
+
+int SSLManager::SSL_get_error(const SSLConnection* conn, int ret) {
+    return ::SSL_get_error(conn->ssl, ret);
+}
+
+int SSLManager::SSL_shutdown(SSLConnection* conn) {
+    int status;
+    do {
+        status = ::SSL_shutdown(conn->ssl);
+    } while (!_doneWithSSLOp(conn, status));
+
+    if (status < 0)
+        _handleSSLError(SSL_get_error(conn, status), status);
+    return status;
+}
+
+void SSLManager::SSL_free(SSLConnection* conn) {
+    return ::SSL_free(conn->ssl);
+}
+
+Status SSLManager::initSSLContext(SSL_CTX* context,
+                                  const SSLParams& params,
+                                  ConnectionDirection direction) {
+    // SSL_OP_ALL - Activate all bug workaround options, to support buggy client SSL's.
+    // SSL_OP_NO_SSLv2 - Disable SSL v2 support
+    // SSL_OP_NO_SSLv3 - Disable SSL v3 support
+    long supportedProtocols = SSL_OP_ALL | SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3;
+
+    // Set the supported TLS protocols. Allow --sslDisabledProtocols to disable selected
+    // ciphers.
+    for (const SSLParams::Protocols& protocol : params.sslDisabledProtocols) {
+        if (protocol == SSLParams::Protocols::TLS1_0) {
+            supportedProtocols |= SSL_OP_NO_TLSv1;
+        } else if (protocol == SSLParams::Protocols::TLS1_1) {
+            supportedProtocols |= SSL_OP_NO_TLSv1_1;
+        } else if (protocol == SSLParams::Protocols::TLS1_2) {
+            supportedProtocols |= SSL_OP_NO_TLSv1_2;
+        }
+    }
+    ::SSL_CTX_set_options(context, supportedProtocols);
+
+    // HIGH - Enable strong ciphers
+    // !EXPORT - Disable export ciphers (40/56 bit)
+    // !aNULL - Disable anonymous auth ciphers
+    // @STRENGTH - Sort ciphers based on strength
+    std::string cipherConfig = "HIGH:!EXPORT:!aNULL@STRENGTH";
+
+    // Allow the cipher configuration string to be overriden by --sslCipherConfig
+    if (!params.sslCipherConfig.empty()) {
+        cipherConfig = params.sslCipherConfig;
+    }
+
+    if (0 == ::SSL_CTX_set_cipher_list(context, cipherConfig.c_str())) {
+        return Status(ErrorCodes::InvalidSSLConfiguration,
+                      str::stream() << "Can not set supported cipher suites: "
+                                    << getSSLErrorMessage(ERR_get_error()));
+    }
+
+    // We use the address of the context as the session id context.
+    if (0 == ::SSL_CTX_set_session_id_context(
+                 context, reinterpret_cast<unsigned char*>(&context), sizeof(context))) {
+        return Status(ErrorCodes::InvalidSSLConfiguration,
+                      str::stream() << "Can not store ssl session id context: "
+                                    << getSSLErrorMessage(ERR_get_error()));
+    }
+
+    if (direction == ConnectionDirection::kOutgoing && !params.sslClusterFile.empty()) {
+        ::EVP_set_pw_prompt("Enter cluster certificate passphrase");
+        if (!_setupPEM(context, params.sslClusterFile, params.sslClusterPassword)) {
+            return Status(ErrorCodes::InvalidSSLConfiguration, "Can not set up ssl clusterFile.");
+        }
+    } else if (!params.sslPEMKeyFile.empty()) {
+        // Use the pemfile for everything else
+        ::EVP_set_pw_prompt("Enter PEM passphrase");
+        if (!_setupPEM(context, params.sslPEMKeyFile, params.sslPEMKeyPassword)) {
+            return Status(ErrorCodes::InvalidSSLConfiguration, "Can not set up PEM key file.");
+        }
+    }
+
+    const auto status =
+        params.sslCAFile.empty() ? _setupSystemCA(context) : _setupCA(context, params.sslCAFile);
+    if (!status.isOK())
+        return status;
+
+    if (!params.sslCRLFile.empty()) {
+        if (!_setupCRL(context, params.sslCRLFile)) {
+            return Status(ErrorCodes::InvalidSSLConfiguration, "Can not set up CRL file.");
+        }
+    }
+
+    if (!params.sslPEMTempDHParam.empty()) {
+        try {
+            std::ifstream dhparamPemFile(params.sslPEMTempDHParam, std::ios_base::binary);
+            if (dhparamPemFile.fail() || dhparamPemFile.bad()) {
+                return Status(ErrorCodes::InvalidSSLConfiguration,
+                              str::stream() << "Cannot open PEM DHParams file.");
+            }
+
+            std::vector<std::uint8_t> paramData{std::istreambuf_iterator<char>(dhparamPemFile),
+                                                std::istreambuf_iterator<char>()};
+            auto bio = makeUniqueMemBio(paramData);
+
+            UniqueDHParams dhparams(::PEM_read_bio_DHparams(bio.get(), nullptr, nullptr, nullptr));
+            if (!dhparams) {
+                return Status(ErrorCodes::InvalidSSLConfiguration,
+                              str::stream() << "Error reading DHParams file."
+                                            << getSSLErrorMessage(ERR_get_error()));
+            }
+
+            if (::SSL_CTX_set_tmp_dh(context, dhparams.get()) != 1) {
+                return Status(ErrorCodes::InvalidSSLConfiguration,
+                              str::stream() << "Failure to set PFS DH parameters: "
+                                            << getSSLErrorMessage(ERR_get_error()));
+            }
+        } catch (const std::exception& ex) {
+            return Status(ErrorCodes::InvalidSSLConfiguration, ex.what());
+        }
+    }
+
+    // We always set ECDH mode anyhow, if available.
+    setECDHModeAuto(context);
+
+    return Status::OK();
+}
+
+bool SSLManager::_initSynchronousSSLContext(UniqueSSLContext* contextPtr,
+                                            const SSLParams& params,
+                                            ConnectionDirection direction) {
+    *contextPtr = UniqueSSLContext(SSL_CTX_new(SSLv23_method()), free_ssl_context);
+
+    uassertStatusOK(initSSLContext(contextPtr->get(), params, direction));
+
+    // If renegotiation is needed, don't return from recv() or send() until it's successful.
+    // Note: this is for blocking sockets only.
+    SSL_CTX_set_mode(contextPtr->get(), SSL_MODE_AUTO_RETRY);
+
+    return true;
+}
+
+unsigned long long SSLManager::_convertASN1ToMillis(ASN1_TIME* asn1time) {
+    BIO* outBIO = BIO_new(BIO_s_mem());
+    int timeError = ASN1_TIME_print(outBIO, asn1time);
+    ON_BLOCK_EXIT(BIO_free, outBIO);
+
+    if (timeError <= 0) {
+        error() << "ASN1_TIME_print failed or wrote no data.";
+        return 0;
+    }
+
+    char dateChar[DATE_LEN];
+    timeError = BIO_gets(outBIO, dateChar, DATE_LEN);
+    if (timeError <= 0) {
+        error() << "BIO_gets call failed to transfer contents to buf";
+        return 0;
+    }
+
+    // Ensure that day format is two digits for parsing.
+    // Jun  8 17:00:03 2014 becomes Jun 08 17:00:03 2014.
+    if (dateChar[4] == ' ') {
+        dateChar[4] = '0';
+    }
+
+    std::istringstream inStringStream((std::string(dateChar, 20)));
+    boost::posix_time::time_input_facet* inputFacet =
+        new boost::posix_time::time_input_facet("%b %d %H:%M:%S %Y");
+
+    inStringStream.imbue(std::locale(std::cout.getloc(), inputFacet));
+    boost::posix_time::ptime posixTime;
+    inStringStream >> posixTime;
+
+    const boost::gregorian::date epoch = boost::gregorian::date(1970, boost::gregorian::Jan, 1);
+
+    return (posixTime - boost::posix_time::ptime(epoch)).total_milliseconds();
+}
+
+bool SSLManager::_parseAndValidateCertificate(const std::string& keyFile,
+                                              const std::string& keyPassword,
+                                              std::string* subjectName,
+                                              Date_t* serverCertificateExpirationDate) {
+    BIO* inBIO = BIO_new(BIO_s_file());
+    if (inBIO == NULL) {
+        error() << "failed to allocate BIO object: " << getSSLErrorMessage(ERR_get_error());
+        return false;
+    }
+
+    ON_BLOCK_EXIT(BIO_free, inBIO);
+    if (BIO_read_filename(inBIO, keyFile.c_str()) <= 0) {
+        error() << "cannot read key file when setting subject name: " << keyFile << ' '
+                << getSSLErrorMessage(ERR_get_error());
+        return false;
+    }
+
+    // Callback will not manipulate the password, so const_cast is safe.
+    X509* x509 = PEM_read_bio_X509(inBIO,
+                                   NULL,
+                                   &SSLManager::password_cb,
+                                   const_cast<void*>(static_cast<const void*>(&keyPassword)));
+    if (x509 == NULL) {
+        error() << "cannot retrieve certificate from keyfile: " << keyFile << ' '
+                << getSSLErrorMessage(ERR_get_error());
+        return false;
+    }
+    ON_BLOCK_EXIT(X509_free, x509);
+
+    *subjectName = getCertificateSubjectName(x509);
+    if (serverCertificateExpirationDate != NULL) {
+        unsigned long long notBeforeMillis = _convertASN1ToMillis(X509_get_notBefore(x509));
+        if (notBeforeMillis == 0) {
+            error() << "date conversion failed";
+            return false;
+        }
+
+        unsigned long long notAfterMillis = _convertASN1ToMillis(X509_get_notAfter(x509));
+        if (notAfterMillis == 0) {
+            error() << "date conversion failed";
+            return false;
+        }
+
+        if ((notBeforeMillis > curTimeMillis64()) || (curTimeMillis64() > notAfterMillis)) {
+            severe() << "The provided SSL certificate is expired or not yet valid.";
+            fassertFailedNoTrace(28652);
+        }
+
+        *serverCertificateExpirationDate = Date_t::fromMillisSinceEpoch(notAfterMillis);
+    }
+
+    return true;
+}
+
+bool SSLManager::_setupPEM(SSL_CTX* context,
+                           const std::string& keyFile,
+                           const std::string& password) {
+    if (SSL_CTX_use_certificate_chain_file(context, keyFile.c_str()) != 1) {
+        error() << "cannot read certificate file: " << keyFile << ' '
+                << getSSLErrorMessage(ERR_get_error());
+        return false;
+    }
+
+    BIO* inBio = BIO_new(BIO_s_file());
+    if (!inBio) {
+        error() << "failed to allocate BIO object: " << getSSLErrorMessage(ERR_get_error());
+        return false;
+    }
+    const auto bioGuard = MakeGuard([&inBio]() { BIO_free(inBio); });
+
+    if (BIO_read_filename(inBio, keyFile.c_str()) <= 0) {
+        error() << "cannot read PEM key file: " << keyFile << ' '
+                << getSSLErrorMessage(ERR_get_error());
+        return false;
+    }
+
+    // If password is empty, use default OpenSSL callback, which uses the terminal
+    // to securely request the password interactively from the user.
+    decltype(&SSLManager::password_cb) password_cb = nullptr;
+    void* userdata = nullptr;
+    if (!password.empty()) {
+        password_cb = &SSLManager::password_cb;
+        // SSLManager::password_cb will not manipulate the password, so const_cast is safe.
+        userdata = const_cast<void*>(static_cast<const void*>(&password));
+    }
+    EVP_PKEY* privateKey = PEM_read_bio_PrivateKey(inBio, nullptr, password_cb, userdata);
+    if (!privateKey) {
+        error() << "cannot read PEM key file: " << keyFile << ' '
+                << getSSLErrorMessage(ERR_get_error());
+        return false;
+    }
+    const auto privateKeyGuard = MakeGuard([&privateKey]() { EVP_PKEY_free(privateKey); });
+
+    if (SSL_CTX_use_PrivateKey(context, privateKey) != 1) {
+        error() << "cannot use PEM key file: " << keyFile << ' '
+                << getSSLErrorMessage(ERR_get_error());
+        return false;
+    }
+
+    // Verify that the certificate and the key go together.
+    if (SSL_CTX_check_private_key(context) != 1) {
+        error() << "SSL certificate validation: " << getSSLErrorMessage(ERR_get_error());
+        return false;
+    }
+
+    return true;
+}
+
+Status SSLManager::_setupCA(SSL_CTX* context, const std::string& caFile) {
+    // Set the list of CAs sent to clients
+    STACK_OF(X509_NAME)* certNames = SSL_load_client_CA_file(caFile.c_str());
+    if (certNames == NULL) {
+        return Status(ErrorCodes::InvalidSSLConfiguration,
+                      str::stream() << "cannot read certificate authority file: " << caFile << " "
+                                    << getSSLErrorMessage(ERR_get_error()));
+    }
+    SSL_CTX_set_client_CA_list(context, certNames);
+
+    // Load trusted CA
+    if (SSL_CTX_load_verify_locations(context, caFile.c_str(), NULL) != 1) {
+        return Status(ErrorCodes::InvalidSSLConfiguration,
+                      str::stream() << "cannot read certificate authority file: " << caFile << " "
+                                    << getSSLErrorMessage(ERR_get_error()));
+    }
+
+    // Set SSL to require peer (client) certificate verification
+    // if a certificate is presented
+    SSL_CTX_set_verify(context, SSL_VERIFY_PEER, &SSLManager::verify_cb);
+    _sslConfiguration.hasCA = true;
+    return Status::OK();
+}
+
+inline Status checkX509_STORE_error() {
+    const auto errCode = ERR_peek_last_error();
+    if (ERR_GET_LIB(errCode) != ERR_LIB_X509 ||
+        ERR_GET_REASON(errCode) != X509_R_CERT_ALREADY_IN_HASH_TABLE) {
+        return {ErrorCodes::InvalidSSLConfiguration,
+                str::stream() << "Error adding certificate to X509 store: "
+                              << ERR_reason_error_string(errCode)};
+    }
+    return Status::OK();
+}
+
+#if defined(_WIN32)
+// This imports the certificates in a given Windows certificate store into an X509_STORE for
+// openssl to use during certificate validation.
+Status importCertStoreToX509_STORE(const wchar_t* storeName,
+                                   DWORD storeLocation,
+                                   X509_STORE* verifyStore) {
+    HCERTSTORE systemStore = CertOpenStore(CERT_STORE_PROV_SYSTEM_W,
+                                           0,
+                                           NULL,
+                                           storeLocation | CERT_STORE_READONLY_FLAG,
+                                           const_cast<LPWSTR>(storeName));
+    if (systemStore == NULL) {
+        return {ErrorCodes::InvalidSSLConfiguration,
+                str::stream() << "error opening system CA store: " << errnoWithDescription()};
+    }
+    auto systemStoreGuard = MakeGuard([systemStore]() { CertCloseStore(systemStore, 0); });
+
+    PCCERT_CONTEXT certCtx = NULL;
+    while ((certCtx = CertEnumCertificatesInStore(systemStore, certCtx)) != NULL) {
+        auto certBytes = static_cast<const unsigned char*>(certCtx->pbCertEncoded);
+        X509* x509Obj = d2i_X509(NULL, &certBytes, certCtx->cbCertEncoded);
+        if (x509Obj == NULL) {
+            return {ErrorCodes::InvalidSSLConfiguration,
+                    str::stream() << "Error parsing X509 object from Windows certificate store"
+                                  << SSLManagerInterface::getSSLErrorMessage(ERR_get_error())};
+        }
+        const auto x509ObjGuard = MakeGuard([&x509Obj]() { X509_free(x509Obj); });
+
+        if (X509_STORE_add_cert(verifyStore, x509Obj) != 1) {
+            auto status = checkX509_STORE_error();
+            if (!status.isOK())
+                return status;
+        }
+    }
+    int lastError = GetLastError();
+    if (lastError != CRYPT_E_NOT_FOUND) {
+        return {ErrorCodes::InvalidSSLConfiguration,
+                str::stream() << "Error enumerating certificates: "
+                              << errnoWithDescription(lastError)};
+    }
+
+    return Status::OK();
+}
+#elif defined(__APPLE__)
+
+template <typename T>
+class CFTypeRefHolder {
+public:
+    explicit CFTypeRefHolder(T ptr) : ref(static_cast<CFTypeRef>(ptr)) {}
+    ~CFTypeRefHolder() {
+        CFRelease(ref);
+    }
+    operator T() {
+        return static_cast<T>(ref);
+    }
+
+private:
+    CFTypeRef ref = nullptr;
+};
+template <typename T>
+CFTypeRefHolder<T> makeCFTypeRefHolder(T ptr) {
+    return CFTypeRefHolder<T>(ptr);
+}
+
+std::string OSStatusToString(OSStatus status) {
+    auto errMsg = makeCFTypeRefHolder(SecCopyErrorMessageString(status, NULL));
+    return std::string{CFStringGetCStringPtr(errMsg, kCFStringEncodingUTF8)};
+}
+
+Status importKeychainToX509_STORE(X509_STORE* verifyStore) {
+    CFArrayRef result;
+    OSStatus status;
+
+    // This copies all the certificates trusted by the system (regardless of what keychain they're
+    // attached to) into a CFArray.
+    if ((status = SecTrustCopyAnchorCertificates(&result)) != 0) {
+        return {ErrorCodes::InvalidSSLConfiguration,
+                str::stream() << "Error enumerating certificates: " << OSStatusToString(status)};
+    }
+    const auto resultGuard = makeCFTypeRefHolder(result);
+
+    for (CFIndex i = 0; i < CFArrayGetCount(result); i++) {
+        SecCertificateRef cert =
+            static_cast<SecCertificateRef>(const_cast<void*>(CFArrayGetValueAtIndex(result, i)));
+
+        auto rawData = makeCFTypeRefHolder(SecCertificateCopyData(cert));
+        if (!rawData) {
+            return {ErrorCodes::InvalidSSLConfiguration,
+                    str::stream() << "Error enumerating certificates: "
+                                  << OSStatusToString(status)};
+        }
+        const uint8_t* rawDataPtr = CFDataGetBytePtr(rawData);
+
+        // Parse an openssl X509 object from each returned certificate
+        X509* x509Cert = d2i_X509(nullptr, &rawDataPtr, CFDataGetLength(rawData));
+        if (!x509Cert) {
+            return {ErrorCodes::InvalidSSLConfiguration,
+                    str::stream() << "Error parsing X509 certificate from system keychain: "
+                                  << ERR_reason_error_string(ERR_peek_last_error())};
+        }
+        const auto x509CertGuard = MakeGuard([&x509Cert]() { X509_free(x509Cert); });
+
+        // Add the parsed X509 object to the X509_STORE verification store
+        if (X509_STORE_add_cert(verifyStore, x509Cert) != 1) {
+            auto status = checkX509_STORE_error();
+            if (!status.isOK())
+                return status;
+        }
+    }
+
+    return Status::OK();
+}
+#endif
+
+Status SSLManager::_setupSystemCA(SSL_CTX* context) {
+#if !defined(_WIN32) && !defined(__APPLE__)
+    // On non-Windows/non-Apple platforms, the OpenSSL libraries should have been configured
+    // with default locations for CA certificates.
+    if (SSL_CTX_set_default_verify_paths(context) != 1) {
+        return {ErrorCodes::InvalidSSLConfiguration,
+                str::stream() << "error loading system CA certificates "
+                              << "(default certificate file: "
+                              << X509_get_default_cert_file()
+                              << ", "
+                              << "default certificate path: "
+                              << X509_get_default_cert_dir()
+                              << ")"};
+    }
+    return Status::OK();
+#else
+
+    X509_STORE* verifyStore = SSL_CTX_get_cert_store(context);
+    if (!verifyStore) {
+        return {ErrorCodes::InvalidSSLConfiguration,
+                "no X509 store found for SSL context while loading system certificates"};
+    }
+#if defined(_WIN32)
+    auto status = importCertStoreToX509_STORE(L"root", CERT_SYSTEM_STORE_CURRENT_USER, verifyStore);
+    if (!status.isOK())
+        return status;
+    return importCertStoreToX509_STORE(L"CA", CERT_SYSTEM_STORE_CURRENT_USER, verifyStore);
+#elif defined(__APPLE__)
+    return importKeychainToX509_STORE(verifyStore);
+#endif
+#endif
+}
+
+bool SSLManager::_setupCRL(SSL_CTX* context, const std::string& crlFile) {
+    X509_STORE* store = SSL_CTX_get_cert_store(context);
+    fassert(16583, store);
+
+    X509_STORE_set_flags(store, X509_V_FLAG_CRL_CHECK);
+    X509_LOOKUP* lookup = X509_STORE_add_lookup(store, X509_LOOKUP_file());
+    fassert(16584, lookup);
+
+    int status = X509_load_crl_file(lookup, crlFile.c_str(), X509_FILETYPE_PEM);
+    if (status == 0) {
+        error() << "cannot read CRL file: " << crlFile << ' '
+                << getSSLErrorMessage(ERR_get_error());
+        return false;
+    }
+    log() << "ssl imported " << status << " revoked certificate" << ((status == 1) ? "" : "s")
+          << " from the revocation list.";
+    return true;
+}
+
+/*
+* The interface layer between network and BIO-pair. The BIO-pair buffers
+* the data to/from the TLS layer.
+*/
+void SSLManager::_flushNetworkBIO(SSLConnection* conn) {
+    char buffer[BUFFER_SIZE];
+    int wantWrite;
+
+    /*
+    * Write the complete contents of the buffer. Leaving the buffer
+    * unflushed could cause a deadlock.
+    */
+    while ((wantWrite = BIO_ctrl_pending(conn->networkBIO)) > 0) {
+        if (wantWrite > BUFFER_SIZE) {
+            wantWrite = BUFFER_SIZE;
+        }
+        int fromBIO = BIO_read(conn->networkBIO, buffer, wantWrite);
+
+        int writePos = 0;
+        do {
+            int numWrite = fromBIO - writePos;
+            numWrite = send(conn->socket->rawFD(), buffer + writePos, numWrite, portSendFlags);
+            if (numWrite < 0) {
+                conn->socket->handleSendError(numWrite, "");
+            }
+            writePos += numWrite;
+        } while (writePos < fromBIO);
+    }
+
+    int wantRead;
+    while ((wantRead = BIO_ctrl_get_read_request(conn->networkBIO)) > 0) {
+        if (wantRead > BUFFER_SIZE) {
+            wantRead = BUFFER_SIZE;
+        }
+
+        int numRead = recv(conn->socket->rawFD(), buffer, wantRead, portRecvFlags);
+        if (numRead <= 0) {
+            conn->socket->handleRecvError(numRead, wantRead);
+            continue;
+        }
+
+        int toBIO = BIO_write(conn->networkBIO, buffer, numRead);
+        if (toBIO != numRead) {
+            LOG(3) << "Failed to write network data to the SSL BIO layer";
+            throwSocketError(SocketErrorKind::RECV_ERROR, conn->socket->remoteString());
+        }
+    }
+}
+
+bool SSLManager::_doneWithSSLOp(SSLConnection* conn, int status) {
+    int sslErr = SSL_get_error(conn, status);
+    switch (sslErr) {
+        case SSL_ERROR_NONE:
+            _flushNetworkBIO(conn);  // success, flush network BIO before leaving
+            return true;
+        case SSL_ERROR_WANT_WRITE:
+        case SSL_ERROR_WANT_READ:
+            _flushNetworkBIO(conn);  // not ready, flush network BIO and try again
+            return false;
+        default:
+            return true;
+    }
+}
+
+SSLConnection* SSLManager::connect(Socket* socket) {
+    std::unique_ptr<SSLConnection> sslConn =
+        stdx::make_unique<SSLConnection>(_clientContext.get(), socket, (const char*)NULL, 0);
+
+    const auto undotted = removeFQDNRoot(socket->remoteAddr().hostOrIp());
+    int ret = ::SSL_set_tlsext_host_name(sslConn->ssl, undotted.c_str());
+    if (ret != 1)
+        _handleSSLError(SSL_get_error(sslConn.get(), ret), ret);
+
+    do {
+        ret = ::SSL_connect(sslConn->ssl);
+    } while (!_doneWithSSLOp(sslConn.get(), ret));
+
+    if (ret != 1)
+        _handleSSLError(SSL_get_error(sslConn.get(), ret), ret);
+
+    return sslConn.release();
+}
+
+SSLConnection* SSLManager::accept(Socket* socket, const char* initialBytes, int len) {
+    std::unique_ptr<SSLConnection> sslConn =
+        stdx::make_unique<SSLConnection>(_serverContext.get(), socket, initialBytes, len);
+
+    int ret;
+    do {
+        ret = ::SSL_accept(sslConn->ssl);
+    } while (!_doneWithSSLOp(sslConn.get(), ret));
+
+    if (ret != 1)
+        _handleSSLError(SSL_get_error(sslConn.get(), ret), ret);
+
+    return sslConn.release();
+}
+
+StatusWith<boost::optional<SSLPeerInfo>> SSLManager::parseAndValidatePeerCertificate(
+    SSL* conn, const std::string& remoteHost) {
+    if (!_sslConfiguration.hasCA && isSSLServer)
+        return {boost::none};
+
+    X509* peerCert = SSL_get_peer_certificate(conn);
+
+    if (NULL == peerCert) {  // no certificate presented by peer
+        if (_weakValidation) {
+            warning() << "no SSL certificate provided by peer";
+        } else {
+            auto msg = "no SSL certificate provided by peer; connection rejected";
+            error() << msg;
+            return Status(ErrorCodes::SSLHandshakeFailed, msg);
+        }
+        return {boost::none};
+    }
+    ON_BLOCK_EXIT(X509_free, peerCert);
+
+    long result = SSL_get_verify_result(conn);
+
+    if (result != X509_V_OK) {
+        if (_allowInvalidCertificates) {
+            warning() << "SSL peer certificate validation failed: "
+                      << X509_verify_cert_error_string(result);
+        } else {
+            str::stream msg;
+            msg << "SSL peer certificate validation failed: "
+                << X509_verify_cert_error_string(result);
+            error() << msg.ss.str();
+            return Status(ErrorCodes::SSLHandshakeFailed, msg);
+        }
+    }
+
+    // TODO: check optional cipher restriction, using cert.
+    std::string peerSubjectName = getCertificateSubjectName(peerCert);
+    LOG(2) << "Accepted TLS connection from peer: " << peerSubjectName;
+
+    StatusWith<stdx::unordered_set<RoleName>> swPeerCertificateRoles = _parsePeerRoles(peerCert);
+    if (!swPeerCertificateRoles.isOK()) {
+        return swPeerCertificateRoles.getStatus();
+    }
+
+    // If this is an SSL client context (on a MongoDB server or client)
+    // perform hostname validation of the remote server
+    if (remoteHost.empty()) {
+        return boost::make_optional(
+            SSLPeerInfo(peerSubjectName, std::move(swPeerCertificateRoles.getValue())));
+    }
+
+    // Try to match using the Subject Alternate Name, if it exists.
+    // RFC-2818 requires the Subject Alternate Name to be used if present.
+    // Otherwise, the most specific Common Name field in the subject field
+    // must be used.
+
+    bool sanMatch = false;
+    bool cnMatch = false;
+    StringBuilder certificateNames;
+
+    STACK_OF(GENERAL_NAME)* sanNames = static_cast<STACK_OF(GENERAL_NAME)*>(
+        X509_get_ext_d2i(peerCert, NID_subject_alt_name, NULL, NULL));
+
+    if (sanNames != NULL) {
+        int sanNamesList = sk_GENERAL_NAME_num(sanNames);
+        certificateNames << "SAN(s): ";
+        for (int i = 0; i < sanNamesList; i++) {
+            const GENERAL_NAME* currentName = sk_GENERAL_NAME_value(sanNames, i);
+            if (currentName && currentName->type == GEN_DNS) {
+                char* dnsName = reinterpret_cast<char*>(ASN1_STRING_data(currentName->d.dNSName));
+                if (hostNameMatchForX509Certificates(remoteHost, dnsName)) {
+                    sanMatch = true;
+                    break;
+                }
+                certificateNames << std::string(dnsName) << " ";
+            }
+        }
+        sk_GENERAL_NAME_pop_free(sanNames, GENERAL_NAME_free);
+    } else if (peerSubjectName.find("CN=") != std::string::npos) {
+        // If Subject Alternate Name (SAN) doesn't exist and Common Name (CN) does,
+        // check Common Name.
+        int cnBegin = peerSubjectName.find("CN=") + 3;
+        int cnEnd = peerSubjectName.find(",", cnBegin);
+        std::string commonName = peerSubjectName.substr(cnBegin, cnEnd - cnBegin);
+
+        if (hostNameMatchForX509Certificates(remoteHost, commonName)) {
+            cnMatch = true;
+        }
+        certificateNames << "CN: " << commonName;
+    } else {
+        certificateNames << "No Common Name (CN) or Subject Alternate Names (SAN) found";
+    }
+
+    if (!sanMatch && !cnMatch) {
+        StringBuilder msgBuilder;
+        msgBuilder << "The server certificate does not match the host name. Hostname: "
+                   << remoteHost << " does not match " << certificateNames.str();
+        std::string msg = msgBuilder.str();
+        if (_allowInvalidCertificates || _allowInvalidHostnames || isUnixDomainSocket(remoteHost)) {
+            warning() << msg;
+        } else {
+            error() << msg;
+            return Status(ErrorCodes::SSLHandshakeFailed, msg);
+        }
+    }
+
+    return boost::make_optional(SSLPeerInfo(peerSubjectName, stdx::unordered_set<RoleName>()));
+}
+
+
+SSLPeerInfo SSLManager::parseAndValidatePeerCertificateDeprecated(const SSLConnection* conn,
+                                                                  const std::string& remoteHost) {
+    auto swPeerSubjectName = parseAndValidatePeerCertificate(conn->ssl, remoteHost);
+    // We can't use uassertStatusOK here because we need to throw a NetworkException.
+    if (!swPeerSubjectName.isOK()) {
+        throwSocketError(SocketErrorKind::CONNECT_ERROR, swPeerSubjectName.getStatus().reason());
+    }
+    return swPeerSubjectName.getValue().get_value_or(SSLPeerInfo());
+}
+
+StatusWith<stdx::unordered_set<RoleName>> SSLManager::_parsePeerRoles(X509* peerCert) const {
+    // exts is owned by the peerCert
+    const STACK_OF(X509_EXTENSION)* exts = X509_get0_extensions(peerCert);
+
+    int extCount = 0;
+    if (exts) {
+        extCount = sk_X509_EXTENSION_num(exts);
+    }
+
+    ASN1_OBJECT* rolesObj = OBJ_nid2obj(_rolesNid);
+
+    // Search all certificate extensions for our own
+    stdx::unordered_set<RoleName> roles;
+    for (int i = 0; i < extCount; i++) {
+        X509_EXTENSION* ex = sk_X509_EXTENSION_value(exts, i);
+        ASN1_OBJECT* obj = X509_EXTENSION_get_object(ex);
+
+        if (!OBJ_cmp(obj, rolesObj)) {
+            // We've found an extension which has our roles OID
+            ASN1_OCTET_STRING* data = X509_EXTENSION_get_data(ex);
+
+            /*
+             * MongoDBAuthorizationGrant ::= CHOICE {
+             *  MongoDBRole,
+             *  ...!UTF8String:"Unrecognized entity in MongoDBAuthorizationGrant"
+             * }
+             * MongoDBAuthorizationGrants ::= SET OF MongoDBAuthorizationGrant
+             */
+            // Extract the set of roles from our extension, and load them into an OpenSSL stack.
+            STACK_OF(ASN1_TYPE)* mongoDBAuthorizationGrants = nullptr;
+
+            // OpenSSL's parsing function will try and manipulate the pointer it's passed. If we
+            // passed it 'data->data' directly, it would modify structures owned by peerCert.
+            const unsigned char* dataBytes = data->data;
+            mongoDBAuthorizationGrants =
+                d2i_ASN1_SET_ANY(&mongoDBAuthorizationGrants, &dataBytes, data->length);
+            if (!mongoDBAuthorizationGrants) {
+                return Status(ErrorCodes::FailedToParse,
+                              "Failed to parse x509 authorization grants");
+            }
+            const auto grantGuard = MakeGuard([&mongoDBAuthorizationGrants]() {
+                sk_ASN1_TYPE_pop_free(mongoDBAuthorizationGrants, ASN1_TYPE_free);
+            });
+
+            /*
+             * MongoDBRole ::= SEQUENCE {
+             *  role     UTF8String,
+             *  database UTF8String
+             * }
+             */
+            // Loop through every role in the stack.
+            ASN1_TYPE* MongoDBRoleWrapped = nullptr;
+            while ((MongoDBRoleWrapped = sk_ASN1_TYPE_pop(mongoDBAuthorizationGrants))) {
+                const auto roleWrappedGuard =
+                    MakeGuard([MongoDBRoleWrapped]() { ASN1_TYPE_free(MongoDBRoleWrapped); });
+
+                if (MongoDBRoleWrapped->type == V_ASN1_SEQUENCE) {
+                    // Unwrap the ASN1Type into a STACK_OF(ASN1_TYPE)
+                    unsigned char* roleBytes = ASN1_STRING_data(MongoDBRoleWrapped->value.sequence);
+                    int roleBytesLength = ASN1_STRING_length(MongoDBRoleWrapped->value.sequence);
+                    ASN1_SEQUENCE_ANY* MongoDBRole = nullptr;
+                    MongoDBRole = d2i_ASN1_SEQUENCE_ANY(
+                        &MongoDBRole, (const unsigned char**)&roleBytes, roleBytesLength);
+                    if (!MongoDBRole) {
+                        return Status(ErrorCodes::FailedToParse,
+                                      "Failed to parse role in x509 authorization grant");
+                    }
+                    const auto roleGuard = MakeGuard(
+                        [&MongoDBRole]() { sk_ASN1_TYPE_pop_free(MongoDBRole, ASN1_TYPE_free); });
+
+                    if (sk_ASN1_TYPE_num(MongoDBRole) != 2) {
+                        return Status(ErrorCodes::FailedToParse,
+                                      "Role entity in MongoDBAuthorizationGrant must have exactly "
+                                      "2 sequence elements");
+                    }
+                    // Extract the subcomponents of the sequence, which are popped off the stack in
+                    // reverse order. Here, parse the role's database.
+                    ASN1_TYPE* roleComponent = sk_ASN1_TYPE_pop(MongoDBRole);
+                    const auto roleDBGuard =
+                        MakeGuard([roleComponent]() { ASN1_TYPE_free(roleComponent); });
+                    if (roleComponent->type != V_ASN1_UTF8STRING) {
+                        return Status(ErrorCodes::FailedToParse,
+                                      "database in MongoDBRole must be a UTF8 string");
+                    }
+                    std::string roleDB(
+                        reinterpret_cast<char*>(ASN1_STRING_data(roleComponent->value.utf8string)));
+
+                    // Parse the role's name.
+                    roleComponent = sk_ASN1_TYPE_pop(MongoDBRole);
+                    const auto roleNameGuard =
+                        MakeGuard([roleComponent]() { ASN1_TYPE_free(roleComponent); });
+                    if (roleComponent->type != V_ASN1_UTF8STRING) {
+                        return Status(ErrorCodes::FailedToParse,
+                                      "role in MongoDBRole must be a UTF8 string");
+                    }
+                    std::string roleName(
+                        reinterpret_cast<char*>(ASN1_STRING_data(roleComponent->value.utf8string)));
+
+                    // Construct a RoleName from the subcomponents
+                    roles.emplace(RoleName(roleName, roleDB));
+
+                } else {
+                    return Status(ErrorCodes::FailedToParse,
+                                  "Unrecognized entity in MongoDBAuthorizationGrant");
+                }
+            }
+            LOG(1) << "MONGODB-X509 authorization parsed the following roles from peer "
+                      "certificate: "
+                   << [&roles]() {
+                          StringBuilder sb;
+                          std::for_each(roles.begin(), roles.end(), [&sb](const RoleName& role) {
+                              sb << role.toString();
+                          });
+                          return sb.str();
+                      }();
+        }
+    }
+
+    return roles;
+}
+
+std::string SSLManagerInterface::getSSLErrorMessage(int code) {
+    // 120 from the SSL documentation for ERR_error_string
+    static const size_t msglen = 120;
+
+    char msg[msglen];
+    ERR_error_string_n(code, msg, msglen);
+    return msg;
+}
+
+void SSLManager::_handleSSLError(int code, int ret) {
+    int err = ERR_get_error();
+
+    switch (code) {
+        case SSL_ERROR_WANT_READ:
+        case SSL_ERROR_WANT_WRITE:
+            // should not happen because we turned on AUTO_RETRY
+            // However, it turns out this CAN happen during a connect, if the other side
+            // accepts the socket connection but fails to do the SSL handshake in a timely
+            // manner.
+            error() << "SSL: " << code << ", possibly timed out during connect";
+            break;
+
+        case SSL_ERROR_ZERO_RETURN:
+            // TODO: Check if we can avoid throwing an exception for this condition
+            LOG(3) << "SSL network connection closed";
+            break;
+        case SSL_ERROR_SYSCALL:
+            // If ERR_get_error returned 0, the error queue is empty
+            // check the return value of the actual SSL operation
+            if (err != 0) {
+                error() << "SSL: " << getSSLErrorMessage(err);
+            } else if (ret == 0) {
+                error() << "Unexpected EOF encountered during SSL communication";
+            } else {
+                error() << "The SSL BIO reported an I/O error " << errnoWithDescription();
+            }
+            break;
+        case SSL_ERROR_SSL: {
+            error() << "SSL: " << getSSLErrorMessage(err);
+            break;
+        }
+
+        default:
+            error() << "unrecognized SSL error";
+            break;
+    }
+    throwSocketError(SocketErrorKind::CONNECT_ERROR, "");
+}
+}  // namespace mongo
+
+// TODO SERVER-11601 Use NFC Unicode canonicalization
+bool mongo::hostNameMatchForX509Certificates(std::string nameToMatch, std::string certHostName) {
+    nameToMatch = removeFQDNRoot(std::move(nameToMatch));
+    certHostName = removeFQDNRoot(std::move(certHostName));
+
+    if (certHostName.size() < 2) {
+        return false;
+    }
+
+    // match wildcard DNS names
+    if (certHostName[0] == '*' && certHostName[1] == '.') {
+        // allow name.example.com if the cert is *.example.com, '*' does not match '.'
+        const char* subName = strchr(nameToMatch.c_str(), '.');
+        return subName && !strcasecmp(certHostName.c_str() + 1, subName);
+    } else {
+        return !strcasecmp(nameToMatch.c_str(), certHostName.c_str());
+    }
+}