boringssl/ssl/tls_method.cc
Matthew Braithwaite b7bc80a9a6 SSL_CONFIG: new struct for sheddable handshake configuration.
|SSL_CONFIG| is a container for bits of configuration that are
unneeded after the handshake completes.  By default it is retained for
the life of the |SSL|, but it may be shed at the caller's option by
calling SSL_set_shed_handshake_config().  This is incompatible with
renegotiation, and with SSL_clear().

|SSL_CONFIG| is reachable by |ssl->config| and by |hs->config|.  The
latter is always non-NULL.  To avoid null checks, I've changed the
signature of a number of functions from |SSL*| arguments to
|SSL_HANDSHAKE*| arguments.

When configuration has been shed, setters that touch |SSL_CONFIG|
return an error value if that is possible.  Setters that return |void|
do nothing.

Getters that request |SSL_CONFIG| values will fail with an |assert| if
the configuration has been shed.  When asserts are compiled out, they
will return an error value.

The aim of this commit is to simplify analysis of split-handshakes by
making it obvious that some bits of state have no effects beyond the
handshake.  It also cuts down on memory usage.

Of note: |SSL_CTX| is still reachable after the configuration has been
shed, and a couple things need to be retained only for the sake of
post-handshake hooks.  Perhaps these can be fixed in time.

Change-Id: Idf09642e0518945b81a1e9fcd7331cc9cf7cc2d6
Bug: 123
Reviewed-on: https://boringssl-review.googlesource.com/27644
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: David Benjamin <davidben@google.com>
2018-05-01 20:40:16 +00:00

277 lines
8.8 KiB
C++

/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.] */
#include <openssl/ssl.h>
#include <assert.h>
#include <string.h>
#include <openssl/buf.h>
#include "../crypto/internal.h"
#include "internal.h"
namespace bssl {
static void ssl3_on_handshake_complete(SSL *ssl) {
// The handshake should have released its final message.
assert(!ssl->s3->has_message);
// During the handshake, |hs_buf| is retained. Release if it there is no
// excess in it. There may be excess left if there server sent Finished and
// HelloRequest in the same record.
//
// TODO(davidben): SChannel does not support this. Reject this case.
if (ssl->s3->hs_buf && ssl->s3->hs_buf->length == 0) {
ssl->s3->hs_buf.reset();
}
}
static bool ssl3_set_read_state(SSL *ssl, UniquePtr<SSLAEADContext> aead_ctx) {
// Cipher changes are forbidden if the current epoch has leftover data.
if (tls_has_unprocessed_handshake_data(ssl)) {
OPENSSL_PUT_ERROR(SSL, SSL_R_BUFFERED_MESSAGES_ON_CIPHER_CHANGE);
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
return false;
}
OPENSSL_memset(ssl->s3->read_sequence, 0, sizeof(ssl->s3->read_sequence));
ssl->s3->aead_read_ctx = std::move(aead_ctx);
return true;
}
static bool ssl3_set_write_state(SSL *ssl, UniquePtr<SSLAEADContext> aead_ctx) {
OPENSSL_memset(ssl->s3->write_sequence, 0, sizeof(ssl->s3->write_sequence));
ssl->s3->aead_write_ctx = std::move(aead_ctx);
return true;
}
static const SSL_PROTOCOL_METHOD kTLSProtocolMethod = {
false /* is_dtls */,
ssl3_new,
ssl3_free,
ssl3_get_message,
ssl3_next_message,
ssl3_open_handshake,
ssl3_open_change_cipher_spec,
ssl3_open_app_data,
ssl3_write_app_data,
ssl3_dispatch_alert,
ssl3_init_message,
ssl3_finish_message,
ssl3_add_message,
ssl3_add_change_cipher_spec,
ssl3_add_alert,
ssl3_flush_flight,
ssl3_on_handshake_complete,
ssl3_set_read_state,
ssl3_set_write_state,
};
static int ssl_noop_x509_check_client_CA_names(
STACK_OF(CRYPTO_BUFFER) *names) {
return 1;
}
static void ssl_noop_x509_clear(CERT *cert) {}
static void ssl_noop_x509_free(CERT *cert) {}
static void ssl_noop_x509_dup(CERT *new_cert, const CERT *cert) {}
static void ssl_noop_x509_flush_cached_leaf(CERT *cert) {}
static void ssl_noop_x509_flush_cached_chain(CERT *cert) {}
static int ssl_noop_x509_session_cache_objects(SSL_SESSION *sess) {
return 1;
}
static int ssl_noop_x509_session_dup(SSL_SESSION *new_session,
const SSL_SESSION *session) {
return 1;
}
static void ssl_noop_x509_session_clear(SSL_SESSION *session) {}
static int ssl_noop_x509_session_verify_cert_chain(SSL_SESSION *session,
SSL_HANDSHAKE *hs,
uint8_t *out_alert) {
return 0;
}
static void ssl_noop_x509_hs_flush_cached_ca_names(SSL_HANDSHAKE *hs) {}
static int ssl_noop_x509_ssl_new(SSL_HANDSHAKE *hs) { return 1; }
static void ssl_noop_x509_ssl_config_free(SSL_CONFIG *cfg) {}
static void ssl_noop_x509_ssl_flush_cached_client_CA(SSL_CONFIG *cfg) {}
static int ssl_noop_x509_ssl_auto_chain_if_needed(SSL_HANDSHAKE *hs) {
return 1;
}
static int ssl_noop_x509_ssl_ctx_new(SSL_CTX *ctx) { return 1; }
static void ssl_noop_x509_ssl_ctx_free(SSL_CTX *ctx) { }
static void ssl_noop_x509_ssl_ctx_flush_cached_client_CA(SSL_CTX *ctx) {}
const SSL_X509_METHOD ssl_noop_x509_method = {
ssl_noop_x509_check_client_CA_names,
ssl_noop_x509_clear,
ssl_noop_x509_free,
ssl_noop_x509_dup,
ssl_noop_x509_flush_cached_chain,
ssl_noop_x509_flush_cached_leaf,
ssl_noop_x509_session_cache_objects,
ssl_noop_x509_session_dup,
ssl_noop_x509_session_clear,
ssl_noop_x509_session_verify_cert_chain,
ssl_noop_x509_hs_flush_cached_ca_names,
ssl_noop_x509_ssl_new,
ssl_noop_x509_ssl_config_free,
ssl_noop_x509_ssl_flush_cached_client_CA,
ssl_noop_x509_ssl_auto_chain_if_needed,
ssl_noop_x509_ssl_ctx_new,
ssl_noop_x509_ssl_ctx_free,
ssl_noop_x509_ssl_ctx_flush_cached_client_CA,
};
} // namespace bssl
using namespace bssl;
const SSL_METHOD *TLS_method(void) {
static const SSL_METHOD kMethod = {
0,
&kTLSProtocolMethod,
&ssl_crypto_x509_method,
};
return &kMethod;
}
const SSL_METHOD *SSLv23_method(void) {
return TLS_method();
}
const SSL_METHOD *TLS_with_buffers_method(void) {
static const SSL_METHOD kMethod = {
0,
&kTLSProtocolMethod,
&ssl_noop_x509_method,
};
return &kMethod;
}
// Legacy version-locked methods.
const SSL_METHOD *TLSv1_2_method(void) {
static const SSL_METHOD kMethod = {
TLS1_2_VERSION,
&kTLSProtocolMethod,
&ssl_crypto_x509_method,
};
return &kMethod;
}
const SSL_METHOD *TLSv1_1_method(void) {
static const SSL_METHOD kMethod = {
TLS1_1_VERSION,
&kTLSProtocolMethod,
&ssl_crypto_x509_method,
};
return &kMethod;
}
const SSL_METHOD *TLSv1_method(void) {
static const SSL_METHOD kMethod = {
TLS1_VERSION,
&kTLSProtocolMethod,
&ssl_crypto_x509_method,
};
return &kMethod;
}
// Legacy side-specific methods.
const SSL_METHOD *TLSv1_2_server_method(void) {
return TLSv1_2_method();
}
const SSL_METHOD *TLSv1_1_server_method(void) {
return TLSv1_1_method();
}
const SSL_METHOD *TLSv1_server_method(void) {
return TLSv1_method();
}
const SSL_METHOD *TLSv1_2_client_method(void) {
return TLSv1_2_method();
}
const SSL_METHOD *TLSv1_1_client_method(void) {
return TLSv1_1_method();
}
const SSL_METHOD *TLSv1_client_method(void) {
return TLSv1_method();
}
const SSL_METHOD *SSLv23_server_method(void) {
return SSLv23_method();
}
const SSL_METHOD *SSLv23_client_method(void) {
return SSLv23_method();
}
const SSL_METHOD *TLS_server_method(void) {
return TLS_method();
}
const SSL_METHOD *TLS_client_method(void) {
return TLS_method();
}