2019-12-18 13:25:03 +02:00

425 lines
11 KiB
C++

/*
* Copyright (c) 2016 MariaDB Corporation Ab
*
* Use of this software is governed by the Business Source License included
* in the LICENSE.TXT file and at www.mariadb.com/bsl11.
*
* Change Date: 2023-12-18
*
* On the date above, in accordance with the Business Source License, use
* of this software will be governed by version 2 or later of the General
* Public License.
*/
/**
* @file ssl.c - SSL generic functions
*
* SSL is intended to be available in conjunction with a variety of protocols
* on either the client or server side.
*
* @verbatim
* Revision History
*
* Date Who Description
* 02/02/16 Martin Brampton Initial implementation
*
* @endverbatim
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <sys/ioctl.h>
#include <maxscale/dcb.hh>
#include <maxscale/poll.hh>
#include <maxscale/service.hh>
#include <maxscale/routingworker.hh>
static RSA* rsa_512 = NULL;
static RSA* rsa_1024 = NULL;
const MXS_ENUM_VALUE ssl_version_values[] =
{
{"MAX", SERVICE_SSL_TLS_MAX},
{"TLSv10", SERVICE_TLS10 },
{"TLSv11", SERVICE_TLS11 },
{"TLSv12", SERVICE_TLS12 },
{"TLSv13", SERVICE_TLS13 },
{NULL}
};
static RSA* create_rsa(int bits)
{
#ifdef OPENSSL_1_1
BIGNUM* bn = BN_new();
BN_set_word(bn, RSA_F4);
RSA* rsa = RSA_new();
RSA_generate_key_ex(rsa, bits, bn, NULL);
BN_free(bn);
return rsa;
#else
return RSA_generate_key(bits, RSA_F4, NULL, NULL);
#endif
}
/**
* The RSA key generation callback function for OpenSSL.
* @param s SSL structure
* @param is_export Not used
* @param keylength Length of the key
* @return Pointer to RSA structure
*/
static RSA* tmp_rsa_callback(SSL* s, int is_export, int keylength)
{
RSA* rsa_tmp = NULL;
switch (keylength)
{
case 512:
if (rsa_512)
{
rsa_tmp = rsa_512;
}
else
{
/* generate on the fly, should not happen in this example */
rsa_tmp = create_rsa(keylength);
rsa_512 = rsa_tmp; /* Remember for later reuse */
}
break;
case 1024:
if (rsa_1024)
{
rsa_tmp = rsa_1024;
}
break;
default:
/* Generating a key on the fly is very costly, so use what is there */
if (rsa_1024)
{
rsa_tmp = rsa_1024;
}
else
{
rsa_tmp = rsa_512; /* Use at least a shorter key */
}
}
return rsa_tmp;
}
/**
* Returns an enum ssl_method_type value as string.
*
* @param method A method type.
* @return The method type expressed as a string.
*/
const char* ssl_method_type_to_string(ssl_method_type_t method_type)
{
switch (method_type)
{
case SERVICE_TLS10:
return "TLSv10";
case SERVICE_TLS11:
return "TLSv11";
case SERVICE_TLS12:
return "TLSv12";
case SERVICE_TLS13:
return "TLSv13";
case SERVICE_SSL_MAX:
case SERVICE_TLS_MAX:
case SERVICE_SSL_TLS_MAX:
return "MAX";
default:
return "Unknown";
}
}
ssl_method_type_t string_to_ssl_method_type(const char* str)
{
if (strcasecmp("MAX", str) == 0)
{
return SERVICE_SSL_TLS_MAX;
}
else if (strcasecmp("TLSV10", str) == 0)
{
return SERVICE_TLS10;
}
else if (strcasecmp("TLSV11", str) == 0)
{
return SERVICE_TLS11;
}
else if (strcasecmp("TLSV12", str) == 0)
{
return SERVICE_TLS12;
}
else if (strcasecmp("TLSV13", str) == 0)
{
return SERVICE_TLS13;
}
return SERVICE_SSL_UNKNOWN;
}
// thread-local non-POD types are not supported with older versions of GCC
static thread_local std::string* ssl_errbuf;
static const char* get_ssl_errors()
{
if (ssl_errbuf == NULL)
{
ssl_errbuf = new std::string;
}
char errbuf[200]; // Enough space according to OpenSSL documentation
ssl_errbuf->clear();
for (int err = ERR_get_error(); err; err = ERR_get_error())
{
if (!ssl_errbuf->empty())
{
ssl_errbuf->append(", ");
}
ssl_errbuf->append(ERR_error_string(err, errbuf));
}
return ssl_errbuf->c_str();
}
namespace maxscale
{
SSLConfig::SSLConfig(const MXS_CONFIG_PARAMETER& params)
: key(params.get_string(CN_SSL_KEY))
, cert(params.get_string(CN_SSL_CERT))
, ca(params.get_string(CN_SSL_CA_CERT))
, version((ssl_method_type_t)params.get_enum(CN_SSL_VERSION, ssl_version_values))
, verify_depth(params.get_integer(CN_SSL_CERT_VERIFY_DEPTH))
, verify_peer(params.get_bool(CN_SSL_VERIFY_PEER_CERTIFICATE))
{
}
// static
std::unique_ptr<SSLContext> SSLContext::create(const MXS_CONFIG_PARAMETER& params)
{
mxb_assert(access(params.get_string(CN_SSL_CA_CERT).c_str(), F_OK) == 0);
mxb_assert(params.get_string(CN_SSL_CERT).empty()
|| access(params.get_string(CN_SSL_CERT).c_str(), F_OK) == 0);
mxb_assert(params.get_string(CN_SSL_KEY).empty()
|| access(params.get_string(CN_SSL_KEY).c_str(), F_OK) == 0);
std::unique_ptr<SSLContext> ssl(new(std::nothrow) SSLContext(SSLConfig(params)));
if (ssl && !ssl->init())
{
ssl.reset();
}
return ssl;
}
SSLContext::SSLContext(const SSLConfig& cfg)
: m_cfg(cfg)
{
}
bool SSLContext::init()
{
bool rval = true;
switch (m_cfg.version)
{
case SERVICE_TLS10:
#ifndef OPENSSL_1_1
m_method = (SSL_METHOD*)TLSv1_method();
#else
MXS_ERROR("TLSv1.0 is not supported on this system.");
return false;
#endif
break;
case SERVICE_TLS11:
#if defined (OPENSSL_1_0) || defined (OPENSSL_1_1)
m_method = (SSL_METHOD*)TLSv1_1_method();
#else
MXS_ERROR("TLSv1.1 is not supported on this system.");
return false;
#endif
break;
case SERVICE_TLS12:
#if defined (OPENSSL_1_0) || defined (OPENSSL_1_1)
m_method = (SSL_METHOD*)TLSv1_2_method();
#else
MXS_ERROR("TLSv1.2 is not supported on this system.");
return false;
#endif
break;
case SERVICE_TLS13:
#ifdef OPENSSL_1_1
m_method = (SSL_METHOD*)TLS_method();
#else
MXS_ERROR("TLSv1.3 is not supported on this system.");
return false;
#endif
break;
/** Rest of these use the maximum available SSL/TLS methods */
case SERVICE_SSL_MAX:
m_method = (SSL_METHOD*)SSLv23_method();
break;
case SERVICE_TLS_MAX:
m_method = (SSL_METHOD*)SSLv23_method();
break;
case SERVICE_SSL_TLS_MAX:
m_method = (SSL_METHOD*)SSLv23_method();
break;
default:
m_method = (SSL_METHOD*)SSLv23_method();
break;
}
m_ctx = SSL_CTX_new(m_method);
if (m_ctx == NULL)
{
MXS_ERROR("SSL context initialization failed: %s", get_ssl_errors());
return false;
}
SSL_CTX_set_default_read_ahead(m_ctx, 0);
/** Enable all OpenSSL bug fixes */
SSL_CTX_set_options(m_ctx, SSL_OP_ALL);
/** Disable SSLv3 */
SSL_CTX_set_options(m_ctx, SSL_OP_NO_SSLv3);
if (m_cfg.version == SERVICE_TLS13)
{
// There is no TLSv1_3_method function as the TLSv1_X_method functions are deprecated in favor of
// disabling them via options.
SSL_CTX_set_options(m_ctx, SSL_OP_NO_TLSv1 | SSL_OP_NO_TLSv1_1 | SSL_OP_NO_TLSv1_2);
}
// Disable session cache
SSL_CTX_set_session_cache_mode(m_ctx, SSL_SESS_CACHE_OFF);
//
// Note: This is not safe if SSL initialization is done concurrently
//
/** Generate the 512-bit and 1024-bit RSA keys */
if (rsa_512 == NULL && (rsa_512 = create_rsa(512)) == NULL)
{
MXS_ERROR("512-bit RSA key generation failed.");
return false;
}
else if (rsa_1024 == NULL && (rsa_1024 = create_rsa(1024)) == NULL)
{
MXS_ERROR("1024-bit RSA key generation failed.");
return false;
}
else
{
mxb_assert(rsa_512 && rsa_1024);
SSL_CTX_set_tmp_rsa_callback(m_ctx, tmp_rsa_callback);
}
mxb_assert(!m_cfg.ca.empty());
/* Load the CA certificate into the SSL_CTX structure */
if (!SSL_CTX_load_verify_locations(m_ctx, m_cfg.ca.c_str(), NULL))
{
MXS_ERROR("Failed to set Certificate Authority file: %s", get_ssl_errors());
return false;
}
if (!m_cfg.cert.empty() && !m_cfg.key.empty())
{
/** Load the server certificate */
if (SSL_CTX_use_certificate_chain_file(m_ctx, m_cfg.cert.c_str()) <= 0)
{
MXS_ERROR("Failed to set server SSL certificate: %s", get_ssl_errors());
return false;
}
/* Load the private-key corresponding to the server certificate */
if (SSL_CTX_use_PrivateKey_file(m_ctx, m_cfg.key.c_str(), SSL_FILETYPE_PEM) <= 0)
{
MXS_ERROR("Failed to set server SSL key: %s", get_ssl_errors());
return false;
}
/* Check if the server certificate and private-key matches */
if (!SSL_CTX_check_private_key(m_ctx))
{
MXS_ERROR("Server SSL certificate and key do not match: %s", get_ssl_errors());
return false;
}
}
/* Set to require peer (client) certificate verification */
if (m_cfg.verify_peer)
{
SSL_CTX_set_verify(m_ctx, SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT, NULL);
}
/* Set the verification depth */
SSL_CTX_set_verify_depth(m_ctx, m_cfg.verify_depth);
return true;
}
SSLContext::~SSLContext()
{
SSL_CTX_free(m_ctx);
}
SSLProvider::SSLProvider(std::unique_ptr<mxs::SSLContext> context)
: m_context {std::move(context)}
{
}
mxs::SSLContext* SSLProvider::context() const
{
mxb_assert_message(mxs::RoutingWorker::get_current(), "Must be used on a RoutingWorker");
return m_context.get();
}
const mxs::SSLConfig* SSLProvider::config() const
{
return m_context ? &(m_context->config()) : nullptr;
}
void SSLProvider::set_context(std::unique_ptr<mxs::SSLContext> ssl)
{
mxb_assert(ssl);
m_context = std::move(ssl);
}
std::string SSLConfig::to_string() const
{
std::ostringstream ss;
ss << "\tSSL initialized: yes\n"
<< "\tSSL method type: " << ssl_method_type_to_string(version) << "\n"
<< "\tSSL certificate verification depth: " << verify_depth << "\n"
<< "\tSSL peer verification : " << (verify_peer ? "true" : "false") << "\n"
<< "\tSSL certificate: " << cert << "\n"
<< "\tSSL key: " << key << "\n"
<< "\tSSL CA certificate: " << ca << "\n";
return ss.str();
}
}