729c24cedb
This patch adds an option to compile freerdp in a valgrind compliant way. The purpose is to ease memchecking when connecting with TLS. We mark bytes retrieved from SSL_read() as plainly defined to prevent the undefined contamination. With the patch and the option activated you get a single warning at connection during the handshake, and nothing after.
989 lines
23 KiB
C
989 lines
23 KiB
C
/**
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* FreeRDP: A Remote Desktop Protocol Implementation
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* Transport Layer Security
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*
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* Copyright 2011-2012 Marc-Andre Moreau <marcandre.moreau@gmail.com>
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifdef HAVE_CONFIG_H
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#include "config.h"
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#endif
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#include <assert.h>
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#include <winpr/crt.h>
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#include <winpr/sspi.h>
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#include <winpr/stream.h>
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#include <freerdp/utils/tcp.h>
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#include <freerdp/crypto/tls.h>
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#ifdef HAVE_VALGRIND_MEMCHECK_H
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#include <valgrind/memcheck.h>
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#endif
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static CryptoCert tls_get_certificate(rdpTls* tls, BOOL peer)
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{
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CryptoCert cert;
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X509* server_cert;
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if (peer)
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server_cert = SSL_get_peer_certificate(tls->ssl);
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else
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server_cert = SSL_get_certificate(tls->ssl);
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if (!server_cert)
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{
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fprintf(stderr, "tls_get_certificate: failed to get the server TLS certificate\n");
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cert = NULL;
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}
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else
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{
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cert = malloc(sizeof(*cert));
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cert->px509 = server_cert;
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}
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return cert;
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}
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static void tls_free_certificate(CryptoCert cert)
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{
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X509_free(cert->px509);
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free(cert);
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}
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#define TLS_SERVER_END_POINT "tls-server-end-point:"
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SecPkgContext_Bindings* tls_get_channel_bindings(X509* cert)
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{
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int PrefixLength;
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BYTE CertificateHash[32];
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UINT32 CertificateHashLength;
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BYTE* ChannelBindingToken;
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UINT32 ChannelBindingTokenLength;
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SEC_CHANNEL_BINDINGS* ChannelBindings;
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SecPkgContext_Bindings* ContextBindings;
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ZeroMemory(CertificateHash, sizeof(CertificateHash));
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X509_digest(cert, EVP_sha256(), CertificateHash, &CertificateHashLength);
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PrefixLength = strlen(TLS_SERVER_END_POINT);
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ChannelBindingTokenLength = PrefixLength + CertificateHashLength;
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ContextBindings = (SecPkgContext_Bindings*) malloc(sizeof(SecPkgContext_Bindings));
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ZeroMemory(ContextBindings, sizeof(SecPkgContext_Bindings));
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ContextBindings->BindingsLength = sizeof(SEC_CHANNEL_BINDINGS) + ChannelBindingTokenLength;
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ChannelBindings = (SEC_CHANNEL_BINDINGS*) malloc(ContextBindings->BindingsLength);
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ZeroMemory(ChannelBindings, ContextBindings->BindingsLength);
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ContextBindings->Bindings = ChannelBindings;
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ChannelBindings->cbApplicationDataLength = ChannelBindingTokenLength;
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ChannelBindings->dwApplicationDataOffset = sizeof(SEC_CHANNEL_BINDINGS);
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ChannelBindingToken = &((BYTE*) ChannelBindings)[ChannelBindings->dwApplicationDataOffset];
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strcpy((char*) ChannelBindingToken, TLS_SERVER_END_POINT);
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CopyMemory(&ChannelBindingToken[PrefixLength], CertificateHash, CertificateHashLength);
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return ContextBindings;
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}
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static void tls_ssl_info_callback(const SSL* ssl, int type, int val)
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{
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if (type & SSL_CB_HANDSHAKE_START)
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{
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}
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}
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int tls_connect(rdpTls* tls)
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{
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CryptoCert cert;
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long options = 0;
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int verify_status;
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int connection_status;
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tls->ctx = SSL_CTX_new(TLSv1_client_method());
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if (!tls->ctx)
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{
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fprintf(stderr, "SSL_CTX_new failed\n");
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return -1;
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}
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//SSL_CTX_set_mode(tls->ctx, SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER | SSL_MODE_ENABLE_PARTIAL_WRITE);
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/**
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* SSL_OP_NO_COMPRESSION:
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*
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* The Microsoft RDP server does not advertise support
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* for TLS compression, but alternative servers may support it.
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* This was observed between early versions of the FreeRDP server
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* and the FreeRDP client, and caused major performance issues,
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* which is why we're disabling it.
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*/
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#ifdef SSL_OP_NO_COMPRESSION
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options |= SSL_OP_NO_COMPRESSION;
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#endif
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/**
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* SSL_OP_TLS_BLOCK_PADDING_BUG:
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*
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* The Microsoft RDP server does *not* support TLS padding.
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* It absolutely needs to be disabled otherwise it won't work.
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*/
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options |= SSL_OP_TLS_BLOCK_PADDING_BUG;
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/**
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* SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS:
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*
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* Just like TLS padding, the Microsoft RDP server does not
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* support empty fragments. This needs to be disabled.
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*/
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options |= SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS;
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SSL_CTX_set_options(tls->ctx, options);
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tls->ssl = SSL_new(tls->ctx);
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if (!tls->ssl)
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{
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fprintf(stderr, "SSL_new failed\n");
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return -1;
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}
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if (tls->tsg)
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{
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tls->bio = BIO_new(tls->methods);
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if (!tls->bio)
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{
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fprintf(stderr, "BIO_new failed\n");
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return -1;
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}
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tls->bio->ptr = tls->tsg;
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SSL_set_bio(tls->ssl, tls->bio, tls->bio);
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SSL_CTX_set_info_callback(tls->ctx, tls_ssl_info_callback);
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}
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else
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{
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if (SSL_set_fd(tls->ssl, tls->sockfd) < 1)
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{
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fprintf(stderr, "SSL_set_fd failed\n");
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return -1;
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}
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}
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connection_status = SSL_connect(tls->ssl);
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if (connection_status <= 0)
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{
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if (tls_print_error("SSL_connect", tls->ssl, connection_status))
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{
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return -1;
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}
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}
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cert = tls_get_certificate(tls, TRUE);
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if (!cert)
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{
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fprintf(stderr, "tls_connect: tls_get_certificate failed to return the server certificate.\n");
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return -1;
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}
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tls->Bindings = tls_get_channel_bindings(cert->px509);
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if (!crypto_cert_get_public_key(cert, &tls->PublicKey, &tls->PublicKeyLength))
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{
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fprintf(stderr, "tls_connect: crypto_cert_get_public_key failed to return the server public key.\n");
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tls_free_certificate(cert);
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return -1;
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}
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verify_status = tls_verify_certificate(tls, cert, tls->hostname, tls->port);
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if (verify_status < 1)
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{
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fprintf(stderr, "tls_connect: certificate not trusted, aborting.\n");
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tls_disconnect(tls);
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}
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tls_free_certificate(cert);
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return verify_status;
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}
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BOOL tls_accept(rdpTls* tls, const char* cert_file, const char* privatekey_file)
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{
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CryptoCert cert;
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long options = 0;
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int connection_status;
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tls->ctx = SSL_CTX_new(SSLv23_server_method());
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if (tls->ctx == NULL)
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{
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fprintf(stderr, "SSL_CTX_new failed\n");
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return FALSE;
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}
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/*
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* SSL_OP_NO_SSLv2:
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*
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* We only want SSLv3 and TLSv1, so disable SSLv2.
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* SSLv3 is used by, eg. Microsoft RDC for Mac OS X.
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*/
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options |= SSL_OP_NO_SSLv2;
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/**
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* SSL_OP_NO_COMPRESSION:
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*
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* The Microsoft RDP server does not advertise support
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* for TLS compression, but alternative servers may support it.
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* This was observed between early versions of the FreeRDP server
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* and the FreeRDP client, and caused major performance issues,
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* which is why we're disabling it.
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*/
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#ifdef SSL_OP_NO_COMPRESSION
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options |= SSL_OP_NO_COMPRESSION;
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#endif
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/**
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* SSL_OP_TLS_BLOCK_PADDING_BUG:
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*
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* The Microsoft RDP server does *not* support TLS padding.
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* It absolutely needs to be disabled otherwise it won't work.
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*/
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options |= SSL_OP_TLS_BLOCK_PADDING_BUG;
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/**
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* SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS:
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*
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* Just like TLS padding, the Microsoft RDP server does not
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* support empty fragments. This needs to be disabled.
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*/
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options |= SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS;
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SSL_CTX_set_options(tls->ctx, options);
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if (SSL_CTX_use_RSAPrivateKey_file(tls->ctx, privatekey_file, SSL_FILETYPE_PEM) <= 0)
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{
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fprintf(stderr, "SSL_CTX_use_RSAPrivateKey_file failed\n");
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fprintf(stderr, "PrivateKeyFile: %s\n", privatekey_file);
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return FALSE;
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}
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tls->ssl = SSL_new(tls->ctx);
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if (!tls->ssl)
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{
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fprintf(stderr, "SSL_new failed\n");
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return FALSE;
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}
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if (SSL_use_certificate_file(tls->ssl, cert_file, SSL_FILETYPE_PEM) <= 0)
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{
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fprintf(stderr, "SSL_use_certificate_file failed\n");
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return FALSE;
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}
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if (SSL_set_fd(tls->ssl, tls->sockfd) < 1)
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{
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fprintf(stderr, "SSL_set_fd failed\n");
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return FALSE;
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}
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while (1)
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{
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connection_status = SSL_accept(tls->ssl);
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if (connection_status <= 0)
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{
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switch (SSL_get_error(tls->ssl, connection_status))
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{
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case SSL_ERROR_WANT_READ:
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case SSL_ERROR_WANT_WRITE:
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break;
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default:
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if (tls_print_error("SSL_accept", tls->ssl, connection_status))
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return FALSE;
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break;
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}
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}
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else
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{
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break;
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}
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}
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cert = tls_get_certificate(tls, FALSE);
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if (!cert)
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{
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fprintf(stderr, "tls_connect: tls_get_certificate failed to return the server certificate.\n");
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return FALSE;
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}
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if (!crypto_cert_get_public_key(cert, &tls->PublicKey, &tls->PublicKeyLength))
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{
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fprintf(stderr, "tls_connect: crypto_cert_get_public_key failed to return the server public key.\n");
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tls_free_certificate(cert);
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return FALSE;
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}
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free(cert);
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fprintf(stderr, "TLS connection accepted\n");
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return TRUE;
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}
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BOOL tls_disconnect(rdpTls* tls)
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{
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if (!tls)
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return FALSE;
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if (tls->ssl)
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{
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if (tls->alertDescription != TLS_ALERT_DESCRIPTION_CLOSE_NOTIFY)
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{
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/**
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* OpenSSL doesn't really expose an API for sending a TLS alert manually.
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*
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* The following code disables the sending of the default "close notify"
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* and then proceeds to force sending a custom TLS alert before shutting down.
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*
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* Manually sending a TLS alert is necessary in certain cases,
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* like when server-side NLA results in an authentication failure.
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*/
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SSL_set_quiet_shutdown(tls->ssl, 1);
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if ((tls->alertLevel == TLS_ALERT_LEVEL_FATAL) && (tls->ssl->session))
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SSL_CTX_remove_session(tls->ssl->ctx, tls->ssl->session);
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tls->ssl->s3->alert_dispatch = 1;
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tls->ssl->s3->send_alert[0] = tls->alertLevel;
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tls->ssl->s3->send_alert[1] = tls->alertDescription;
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if (tls->ssl->s3->wbuf.left == 0)
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tls->ssl->method->ssl_dispatch_alert(tls->ssl);
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SSL_shutdown(tls->ssl);
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}
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else
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{
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SSL_shutdown(tls->ssl);
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}
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}
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return TRUE;
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}
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int tls_read(rdpTls* tls, BYTE* data, int length)
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{
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int error;
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int status;
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if (!tls)
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return -1;
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if (!tls->ssl)
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return -1;
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status = SSL_read(tls->ssl, data, length);
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if (status == 0)
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{
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return -1; /* peer disconnected */
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}
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if (status <= 0)
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{
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error = SSL_get_error(tls->ssl, status);
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//fprintf(stderr, "tls_read: length: %d status: %d error: 0x%08X\n",
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// length, status, error);
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switch (error)
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{
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case SSL_ERROR_NONE:
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break;
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case SSL_ERROR_WANT_READ:
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case SSL_ERROR_WANT_WRITE:
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status = 0;
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break;
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case SSL_ERROR_SYSCALL:
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#ifdef _WIN32
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if (WSAGetLastError() == WSAEWOULDBLOCK)
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#else
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if ((errno == EAGAIN) || (errno == 0))
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#endif
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{
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status = 0;
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}
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else
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{
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if (tls_print_error("SSL_read", tls->ssl, status))
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{
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status = -1;
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}
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else
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{
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status = 0;
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}
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}
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break;
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default:
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if (tls_print_error("SSL_read", tls->ssl, status))
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{
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status = -1;
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}
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else
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{
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status = 0;
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}
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break;
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}
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}
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#ifdef HAVE_VALGRIND_MEMCHECK_H
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VALGRIND_MAKE_MEM_DEFINED(data, status);
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#endif
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return status;
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}
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int tls_write(rdpTls* tls, BYTE* data, int length)
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{
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int error;
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int status;
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if (!tls)
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return -1;
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if (!tls->ssl)
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return -1;
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status = SSL_write(tls->ssl, data, length);
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if (status == 0)
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{
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return -1; /* peer disconnected */
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}
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if (status < 0)
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{
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error = SSL_get_error(tls->ssl, status);
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//fprintf(stderr, "tls_write: length: %d status: %d error: 0x%08X\n", length, status, error);
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switch (error)
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{
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case SSL_ERROR_NONE:
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break;
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case SSL_ERROR_WANT_READ:
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case SSL_ERROR_WANT_WRITE:
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status = 0;
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break;
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case SSL_ERROR_SYSCALL:
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if (errno == EAGAIN)
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{
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status = 0;
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}
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else
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{
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tls_print_error("SSL_write", tls->ssl, status);
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status = -1;
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}
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break;
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default:
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tls_print_error("SSL_write", tls->ssl, status);
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status = -1;
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break;
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}
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}
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return status;
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}
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int tls_write_all(rdpTls* tls, BYTE* data, int length)
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{
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int status;
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int sent = 0;
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do
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{
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status = tls_write(tls, &data[sent], length - sent);
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if (status > 0)
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sent += status;
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else if (status == 0)
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tls_wait_write(tls);
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if (sent >= length)
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break;
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}
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while (status >= 0);
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if (status > 0)
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return length;
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else
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return status;
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}
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int tls_wait_read(rdpTls* tls)
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{
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return freerdp_tcp_wait_read(tls->sockfd);
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}
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int tls_wait_write(rdpTls* tls)
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{
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return freerdp_tcp_wait_write(tls->sockfd);
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}
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static void tls_errors(const char *prefix)
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{
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unsigned long error;
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while ((error = ERR_get_error()) != 0)
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fprintf(stderr, "%s: %s\n", prefix, ERR_error_string(error, NULL));
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}
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BOOL tls_print_error(char* func, SSL* connection, int value)
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{
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switch (SSL_get_error(connection, value))
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{
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case SSL_ERROR_ZERO_RETURN:
|
|
fprintf(stderr, "%s: Server closed TLS connection\n", func);
|
|
return TRUE;
|
|
|
|
case SSL_ERROR_WANT_READ:
|
|
fprintf(stderr, "%s: SSL_ERROR_WANT_READ\n", func);
|
|
return FALSE;
|
|
|
|
case SSL_ERROR_WANT_WRITE:
|
|
fprintf(stderr, "%s: SSL_ERROR_WANT_WRITE\n", func);
|
|
return FALSE;
|
|
|
|
case SSL_ERROR_SYSCALL:
|
|
#ifdef _WIN32
|
|
fprintf(stderr, "%s: I/O error: %d\n", func, WSAGetLastError());
|
|
#else
|
|
fprintf(stderr, "%s: I/O error: %s (%d)\n", func, strerror(errno), errno);
|
|
#endif
|
|
tls_errors(func);
|
|
return TRUE;
|
|
|
|
case SSL_ERROR_SSL:
|
|
fprintf(stderr, "%s: Failure in SSL library (protocol error?)\n", func);
|
|
tls_errors(func);
|
|
return TRUE;
|
|
|
|
default:
|
|
fprintf(stderr, "%s: Unknown error\n", func);
|
|
tls_errors(func);
|
|
return TRUE;
|
|
}
|
|
}
|
|
|
|
int tls_set_alert_code(rdpTls* tls, int level, int description)
|
|
{
|
|
tls->alertLevel = level;
|
|
tls->alertDescription = description;
|
|
|
|
return 0;
|
|
}
|
|
|
|
BOOL tls_match_hostname(char *pattern, int pattern_length, char *hostname)
|
|
{
|
|
if (strlen(hostname) == pattern_length)
|
|
{
|
|
if (memcmp((void*) hostname, (void*) pattern, pattern_length) == 0)
|
|
return TRUE;
|
|
}
|
|
|
|
if ((pattern_length > 2) && (pattern[0] == '*') && (pattern[1] == '.') && (((int) strlen(hostname)) >= pattern_length))
|
|
{
|
|
char* check_hostname = &hostname[strlen(hostname) - pattern_length + 1];
|
|
|
|
if (memcmp((void*) check_hostname, (void*) &pattern[1], pattern_length - 1) == 0)
|
|
{
|
|
return TRUE;
|
|
}
|
|
}
|
|
|
|
return FALSE;
|
|
}
|
|
|
|
int tls_verify_certificate(rdpTls* tls, CryptoCert cert, char* hostname, int port)
|
|
{
|
|
int match;
|
|
int index;
|
|
char* common_name = NULL;
|
|
int common_name_length = 0;
|
|
char** alt_names = NULL;
|
|
int alt_names_count = 0;
|
|
int* alt_names_lengths = NULL;
|
|
BOOL certificate_status;
|
|
BOOL hostname_match = FALSE;
|
|
BOOL verification_status = FALSE;
|
|
rdpCertificateData* certificate_data;
|
|
|
|
if (tls->settings->ExternalCertificateManagement)
|
|
{
|
|
BIO* bio;
|
|
int status;
|
|
int length;
|
|
int offset;
|
|
BYTE* pemCert;
|
|
freerdp* instance = (freerdp*) tls->settings->instance;
|
|
|
|
/**
|
|
* Don't manage certificates internally, leave it up entirely to the external client implementation
|
|
*/
|
|
|
|
bio = BIO_new(BIO_s_mem());
|
|
|
|
if (!bio)
|
|
{
|
|
fprintf(stderr, "tls_verify_certificate: BIO_new() failure\n");
|
|
return -1;
|
|
}
|
|
|
|
status = PEM_write_bio_X509(bio, cert->px509);
|
|
|
|
if (status < 0)
|
|
{
|
|
fprintf(stderr, "tls_verify_certificate: PEM_write_bio_X509 failure: %d\n", status);
|
|
return -1;
|
|
}
|
|
|
|
offset = 0;
|
|
length = 2048;
|
|
pemCert = (BYTE*) malloc(length + 1);
|
|
|
|
status = BIO_read(bio, pemCert, length);
|
|
|
|
if (status < 0)
|
|
{
|
|
fprintf(stderr, "tls_verify_certificate: failed to read certificate\n");
|
|
return -1;
|
|
}
|
|
|
|
offset += status;
|
|
|
|
while (offset >= length)
|
|
{
|
|
length *= 2;
|
|
pemCert = (BYTE*) realloc(pemCert, length + 1);
|
|
|
|
status = BIO_read(bio, &pemCert[offset], length);
|
|
|
|
if (status < 0)
|
|
break;
|
|
|
|
offset += status;
|
|
}
|
|
|
|
if (status < 0)
|
|
{
|
|
fprintf(stderr, "tls_verify_certificate: failed to read certificate\n");
|
|
return -1;
|
|
}
|
|
|
|
length = offset;
|
|
pemCert[length] = '\0';
|
|
|
|
status = -1;
|
|
|
|
if (instance->VerifyX509Certificate)
|
|
{
|
|
status = instance->VerifyX509Certificate(instance, pemCert, length, hostname, port, 0);
|
|
}
|
|
|
|
fprintf(stderr, "VerifyX509Certificate: (length = %d) status: %d\n%s\n",
|
|
length, status, pemCert);
|
|
|
|
free(pemCert);
|
|
BIO_free(bio);
|
|
|
|
if (status < 0)
|
|
return -1;
|
|
|
|
return (status == 0) ? 0 : 1;
|
|
}
|
|
|
|
/* ignore certificate verification if user explicitly required it (discouraged) */
|
|
if (tls->settings->IgnoreCertificate)
|
|
return 1; /* success! */
|
|
|
|
/* if user explicitly specified a certificate name, use it instead of the hostname */
|
|
if (tls->settings->CertificateName)
|
|
hostname = tls->settings->CertificateName;
|
|
|
|
/* attempt verification using OpenSSL and the ~/.freerdp/certs certificate store */
|
|
certificate_status = x509_verify_certificate(cert, tls->certificate_store->path);
|
|
|
|
/* verify certificate name match */
|
|
certificate_data = crypto_get_certificate_data(cert->px509, hostname);
|
|
|
|
/* extra common name and alternative names */
|
|
common_name = crypto_cert_subject_common_name(cert->px509, &common_name_length);
|
|
alt_names = crypto_cert_subject_alt_name(cert->px509, &alt_names_count, &alt_names_lengths);
|
|
|
|
/* compare against common name */
|
|
|
|
if (common_name)
|
|
{
|
|
if (tls_match_hostname(common_name, common_name_length, hostname))
|
|
hostname_match = TRUE;
|
|
}
|
|
|
|
/* compare against alternative names */
|
|
|
|
if (alt_names)
|
|
{
|
|
for (index = 0; index < alt_names_count; index++)
|
|
{
|
|
if (tls_match_hostname(alt_names[index], alt_names_lengths[index], hostname))
|
|
{
|
|
hostname_match = TRUE;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* if the certificate is valid and the certificate name matches, verification succeeds */
|
|
if (certificate_status && hostname_match)
|
|
{
|
|
if (common_name)
|
|
{
|
|
free(common_name);
|
|
common_name = NULL;
|
|
}
|
|
|
|
verification_status = TRUE; /* success! */
|
|
}
|
|
|
|
/* if the certificate is valid but the certificate name does not match, warn user, do not accept */
|
|
if (certificate_status && !hostname_match)
|
|
tls_print_certificate_name_mismatch_error(hostname, common_name, alt_names, alt_names_count);
|
|
|
|
/* verification could not succeed with OpenSSL, use known_hosts file and prompt user for manual verification */
|
|
|
|
if (!certificate_status)
|
|
{
|
|
char* issuer;
|
|
char* subject;
|
|
char* fingerprint;
|
|
freerdp* instance = (freerdp*) tls->settings->instance;
|
|
BOOL accept_certificate = FALSE;
|
|
|
|
issuer = crypto_cert_issuer(cert->px509);
|
|
subject = crypto_cert_subject(cert->px509);
|
|
fingerprint = crypto_cert_fingerprint(cert->px509);
|
|
|
|
/* search for matching entry in known_hosts file */
|
|
match = certificate_data_match(tls->certificate_store, certificate_data);
|
|
|
|
if (match == 1)
|
|
{
|
|
/* no entry was found in known_hosts file, prompt user for manual verification */
|
|
if (!hostname_match)
|
|
tls_print_certificate_name_mismatch_error(hostname, common_name, alt_names, alt_names_count);
|
|
|
|
if (instance->VerifyCertificate)
|
|
{
|
|
accept_certificate = instance->VerifyCertificate(instance, subject, issuer, fingerprint);
|
|
}
|
|
|
|
if (!accept_certificate)
|
|
{
|
|
/* user did not accept, abort and do not add entry in known_hosts file */
|
|
verification_status = FALSE; /* failure! */
|
|
}
|
|
else
|
|
{
|
|
/* user accepted certificate, add entry in known_hosts file */
|
|
certificate_data_print(tls->certificate_store, certificate_data);
|
|
verification_status = TRUE; /* success! */
|
|
}
|
|
}
|
|
else if (match == -1)
|
|
{
|
|
/* entry was found in known_hosts file, but fingerprint does not match. ask user to use it */
|
|
tls_print_certificate_error(hostname, fingerprint, tls->certificate_store->file);
|
|
|
|
if (instance->VerifyChangedCertificate)
|
|
{
|
|
accept_certificate = instance->VerifyChangedCertificate(instance, subject, issuer, fingerprint, "");
|
|
}
|
|
|
|
if (!accept_certificate)
|
|
{
|
|
/* user did not accept, abort and do not change known_hosts file */
|
|
verification_status = FALSE; /* failure! */
|
|
}
|
|
else
|
|
{
|
|
/* user accepted new certificate, add replace fingerprint for this host in known_hosts file */
|
|
certificate_data_replace(tls->certificate_store, certificate_data);
|
|
verification_status = TRUE; /* success! */
|
|
}
|
|
}
|
|
else if (match == 0)
|
|
{
|
|
verification_status = TRUE; /* success! */
|
|
}
|
|
|
|
free(issuer);
|
|
free(subject);
|
|
free(fingerprint);
|
|
}
|
|
|
|
if (certificate_data)
|
|
{
|
|
free(certificate_data->fingerprint);
|
|
free(certificate_data->hostname);
|
|
free(certificate_data);
|
|
}
|
|
|
|
#ifndef _WIN32
|
|
if (common_name)
|
|
free(common_name);
|
|
#endif
|
|
|
|
if (alt_names)
|
|
crypto_cert_subject_alt_name_free(alt_names_count, alt_names_lengths,
|
|
alt_names);
|
|
|
|
return (verification_status == 0) ? 0 : 1;
|
|
}
|
|
|
|
void tls_print_certificate_error(char* hostname, char* fingerprint, char *hosts_file)
|
|
{
|
|
fprintf(stderr, "The host key for %s has changed\n", hostname);
|
|
fprintf(stderr, "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@\n");
|
|
fprintf(stderr, "@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @\n");
|
|
fprintf(stderr, "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@\n");
|
|
fprintf(stderr, "IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!\n");
|
|
fprintf(stderr, "Someone could be eavesdropping on you right now (man-in-the-middle attack)!\n");
|
|
fprintf(stderr, "It is also possible that a host key has just been changed.\n");
|
|
fprintf(stderr, "The fingerprint for the host key sent by the remote host is\n%s\n", fingerprint);
|
|
fprintf(stderr, "Please contact your system administrator.\n");
|
|
fprintf(stderr, "Add correct host key in %s to get rid of this message.\n", hosts_file);
|
|
fprintf(stderr, "Host key for %s has changed and you have requested strict checking.\n", hostname);
|
|
fprintf(stderr, "Host key verification failed.\n");
|
|
}
|
|
|
|
void tls_print_certificate_name_mismatch_error(char* hostname, char* common_name, char** alt_names, int alt_names_count)
|
|
{
|
|
int index;
|
|
|
|
assert(NULL != hostname);
|
|
|
|
fprintf(stderr, "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@\n");
|
|
fprintf(stderr, "@ WARNING: CERTIFICATE NAME MISMATCH! @\n");
|
|
fprintf(stderr, "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@\n");
|
|
fprintf(stderr, "The hostname used for this connection (%s) \n", hostname);
|
|
fprintf(stderr, "does not match %s given in the certificate:\n", alt_names_count < 1 ? "the name" : "any of the names");
|
|
fprintf(stderr, "Common Name (CN):\n");
|
|
fprintf(stderr, "\t%s\n", common_name ? common_name : "no CN found in certificate");
|
|
if (alt_names_count > 0)
|
|
{
|
|
assert(NULL != alt_names);
|
|
fprintf(stderr, "Alternative names:\n");
|
|
for (index = 0; index < alt_names_count; index++)
|
|
{
|
|
assert(alt_names[index]);
|
|
fprintf(stderr, "\t %s\n", alt_names[index]);
|
|
}
|
|
}
|
|
fprintf(stderr, "A valid certificate for the wrong name should NOT be trusted!\n");
|
|
}
|
|
|
|
rdpTls* tls_new(rdpSettings* settings)
|
|
{
|
|
rdpTls* tls;
|
|
|
|
tls = (rdpTls*) malloc(sizeof(rdpTls));
|
|
|
|
if (tls)
|
|
{
|
|
ZeroMemory(tls, sizeof(rdpTls));
|
|
|
|
SSL_load_error_strings();
|
|
SSL_library_init();
|
|
|
|
tls->settings = settings;
|
|
tls->certificate_store = certificate_store_new(settings);
|
|
|
|
tls->alertLevel = TLS_ALERT_LEVEL_WARNING;
|
|
tls->alertDescription = TLS_ALERT_DESCRIPTION_CLOSE_NOTIFY;
|
|
}
|
|
|
|
return tls;
|
|
}
|
|
|
|
void tls_free(rdpTls* tls)
|
|
{
|
|
if (tls)
|
|
{
|
|
if (tls->ssl)
|
|
{
|
|
SSL_free(tls->ssl);
|
|
tls->ssl = NULL;
|
|
}
|
|
|
|
if (tls->ctx)
|
|
{
|
|
SSL_CTX_free(tls->ctx);
|
|
tls->ctx = NULL;
|
|
}
|
|
|
|
if (tls->PublicKey)
|
|
{
|
|
free(tls->PublicKey);
|
|
tls->PublicKey = NULL;
|
|
}
|
|
|
|
if (tls->Bindings)
|
|
{
|
|
free(tls->Bindings->Bindings);
|
|
free(tls->Bindings);
|
|
tls->Bindings = NULL;
|
|
}
|
|
|
|
certificate_store_free(tls->certificate_store);
|
|
tls->certificate_store = NULL;
|
|
|
|
free(tls);
|
|
}
|
|
}
|