BOOL tls_accept(rdpTls* tls, BIO *underlying, const char* cert_file, const char* privatekey_file)
{
long options = 0;
/**
* SSL_OP_NO_SSLv2:
*
* We only want SSLv3 and TLSv1, so disable SSLv2.
* SSLv3 is used by, eg. Microsoft RDC for Mac OS X.
*/
options |= SSL_OP_NO_SSLv2;
/**
* SSL_OP_NO_COMPRESSION:
*
* The Microsoft RDP server does not advertise support
* for TLS compression, but alternative servers may support it.
* This was observed between early versions of the FreeRDP server
* and the FreeRDP client, and caused major performance issues,
* which is why we're disabling it.
*/
#ifdef SSL_OP_NO_COMPRESSION
options |= SSL_OP_NO_COMPRESSION;
#endif
/**
* SSL_OP_TLS_BLOCK_PADDING_BUG:
*
* The Microsoft RDP server does *not* support TLS padding.
* It absolutely needs to be disabled otherwise it won't work.
*/
options |= SSL_OP_TLS_BLOCK_PADDING_BUG;
/**
* SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS:
*
* Just like TLS padding, the Microsoft RDP server does not
* support empty fragments. This needs to be disabled.
*/
options |= SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS;
if (!tls_prepare(tls, underlying, SSLv23_server_method(), options, FALSE))
return FALSE;
if (SSL_use_RSAPrivateKey_file(tls->ssl, privatekey_file, SSL_FILETYPE_PEM) <= 0)
{
DEBUG_WARN( "%s: SSL_CTX_use_RSAPrivateKey_file failed\n", __FUNCTION__);
DEBUG_WARN( "PrivateKeyFile: %s\n", privatekey_file);
return FALSE;
}
if (SSL_use_certificate_file(tls->ssl, cert_file, SSL_FILETYPE_PEM) <= 0)
{
DEBUG_WARN( "%s: SSL_use_certificate_file failed\n", __FUNCTION__);
return FALSE;
}
return tls_do_handshake(tls, FALSE) > 0;
}
static void
tls_exec_server(const char *user, int startfd, const char *privkey,
const char *cert, int debuglevel)
{
SSL_CTX *sslctx;
SSL *ssl;
int sockfd, tcpfd, ret;
pjdlog_debug_set(debuglevel);
pjdlog_prefix_set("[TLS sandbox] (server) ");
#ifdef HAVE_SETPROCTITLE
setproctitle("[TLS sandbox] (server) ");
#endif
sockfd = startfd;
tcpfd = startfd + 1;
SSL_load_error_strings();
SSL_library_init();
sslctx = SSL_CTX_new(TLSv1_server_method());
if (sslctx == NULL)
pjdlog_exitx(EX_TEMPFAIL, "SSL_CTX_new() failed.");
SSL_CTX_set_options(sslctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3);
ssl = SSL_new(sslctx);
if (ssl == NULL)
pjdlog_exitx(EX_TEMPFAIL, "SSL_new() failed.");
if (SSL_use_RSAPrivateKey_file(ssl, privkey, SSL_FILETYPE_PEM) != 1) {
ssl_log_errors();
pjdlog_exitx(EX_CONFIG,
"SSL_use_RSAPrivateKey_file(%s) failed.", privkey);
}
if (SSL_use_certificate_file(ssl, cert, SSL_FILETYPE_PEM) != 1) {
ssl_log_errors();
pjdlog_exitx(EX_CONFIG, "SSL_use_certificate_file(%s) failed.",
cert);
}
if (sandbox(user, true, "proto_tls server") != 0)
pjdlog_exitx(EX_CONFIG, "Unable to sandbox TLS server.");
pjdlog_debug(1, "Privileges successfully dropped.");
nonblock(sockfd);
nonblock(tcpfd);
if (SSL_set_fd(ssl, tcpfd) != 1)
pjdlog_exitx(EX_TEMPFAIL, "SSL_set_fd() failed.");
ret = SSL_accept(ssl);
ssl_check_error(ssl, ret);
tls_loop(sockfd, ssl);
}
/* Load certificate and private key */
static void tls_certkey(SSL *_tls)
{
int ret, ret2;
if(!_tls)
{
TLSERROR("Certificate cannot be loaded.");
return;
}
if((!_key) || (!_cert) || (!_callback))
{
printf("WARNING: certificates are disabled!\n");
return;
}
SSL_CTX_set_default_passwd_cb(_tlsctx, _callback);
/*ret = SSL_CTX_load_verify_locations(_tlsctx, "/usr/lib/ssl/cacert.pem", NULL);
if(ret != 1)
{
TLSERROR("Couldn't load root CA file!");
ret2 = ERR_get_error();
printf("EXT: %s\n%s\n%s\n%s\n%s\n", tls_exterror(_tls, ret), ERR_error_string(ret2, NULL),
ERR_lib_error_string(ret2), ERR_func_error_string(ret2), ERR_reason_error_string(ret2));
}*/
ret = SSL_use_RSAPrivateKey_file(_tls, _key, SSL_FILETYPE_PEM);
if(ret != 1)
{
TLSERROR("Error loading TLS PEM private key.");
ret2 = ERR_get_error();
printf("EXT: %s\n%s\n%s\n%s\n%s\n", tls_exterror(_tls, ret), ERR_error_string(ret2, NULL),
ERR_lib_error_string(ret2), ERR_func_error_string(ret2), ERR_reason_error_string(ret2));
}
ret = SSL_use_certificate_file(_tls, _cert, SSL_FILETYPE_PEM);
if(ret != 1) TLSERROR("Error loading TLS PEM certificate.");
ret = SSL_check_private_key(_tls);
if(!ret) TLSERROR("Private key doesn't match certificate public key.");
printf("*** certificate loaded ***\n");
}
BOOL tls_accept(rdpTls* tls, BIO* underlying, const char* cert_file, const char* privatekey_file)
{
long options = 0;
/**
* SSL_OP_NO_SSLv2:
*
* We only want SSLv3 and TLSv1, so disable SSLv2.
* SSLv3 is used by, eg. Microsoft RDC for Mac OS X.
*/
options |= SSL_OP_NO_SSLv2;
/**
* SSL_OP_NO_COMPRESSION:
*
* The Microsoft RDP server does not advertise support
* for TLS compression, but alternative servers may support it.
* This was observed between early versions of the FreeRDP server
* and the FreeRDP client, and caused major performance issues,
* which is why we're disabling it.
*/
#ifdef SSL_OP_NO_COMPRESSION
options |= SSL_OP_NO_COMPRESSION;
#endif
/**
* SSL_OP_TLS_BLOCK_PADDING_BUG:
*
* The Microsoft RDP server does *not* support TLS padding.
* It absolutely needs to be disabled otherwise it won't work.
*/
options |= SSL_OP_TLS_BLOCK_PADDING_BUG;
/**
* SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS:
*
* Just like TLS padding, the Microsoft RDP server does not
* support empty fragments. This needs to be disabled.
*/
options |= SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS;
if (!tls_prepare(tls, underlying, SSLv23_server_method(), options, FALSE))
return FALSE;
if (SSL_use_RSAPrivateKey_file(tls->ssl, privatekey_file, SSL_FILETYPE_PEM) <= 0)
{
WLog_ERR(TAG, "SSL_CTX_use_RSAPrivateKey_file failed");
WLog_ERR(TAG, "PrivateKeyFile: %s", privatekey_file);
return FALSE;
}
if (SSL_use_certificate_file(tls->ssl, cert_file, SSL_FILETYPE_PEM) <= 0)
{
WLog_ERR(TAG, "SSL_use_certificate_file failed");
return FALSE;
}
#ifndef OPENSSL_NO_TLSEXT
/**
* The Microsoft iOS clients eventually send a null or even double null
* terminated hostname in the SNI TLS extension!
* If the length indicator does not equal the hostname strlen OpenSSL
* will abort (see openssl:ssl/t1_lib.c).
* Here is a tcpdump segment of Microsoft Remote Desktop Client Version
* 8.1.7 running on an iPhone 4 with iOS 7.1.2 showing the transmitted
* SNI hostname TLV blob when connection to server "abcd":
* 00 name_type 0x00 (host_name)
* 00 06 length_in_bytes 0x0006
* 61 62 63 64 00 00 host_name "abcd\0\0"
*
* Currently the only (runtime) workaround is setting an openssl tls
* extension debug callback that sets the SSL context's servername_done
* to 1 which effectively disables the parsing of that extension type.
*/
SSL_set_tlsext_debug_callback(tls->ssl, tls_openssl_tlsext_debug_callback);
#endif
return tls_do_handshake(tls, FALSE) > 0;
}
