openssl/ssl/s3_msg.c
Matt Caswell 5d67110173 Don't calculate the Finished MAC twice
In <= TLSv1.2 a Finished message always comes immediately after a CCS
except in the case of NPN where there is an additional message between
the CCS and Finished. Historically we always calculated the Finished MAC
when we processed the CCS. However to deal with NPN we also calculated it
when we receive the Finished message. Really this should only have been
done if we hand negotiated NPN.

This simplifies the code to only calculate the MAC when we receive the
Finished. In 1.1.1 we need to do it this way anyway because there is no
CCS (except in middlebox compat mode) in TLSv1.3.

Coincidentally, this commit also fixes the fact that no-nextprotoneg does
not currently work in master.

Reviewed-by: Andy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5285)
2018-02-09 15:27:32 +00:00

105 lines
3.1 KiB
C

/*
* Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include "ssl_locl.h"
int ssl3_do_change_cipher_spec(SSL *s)
{
int i;
if (s->server)
i = SSL3_CHANGE_CIPHER_SERVER_READ;
else
i = SSL3_CHANGE_CIPHER_CLIENT_READ;
if (s->s3->tmp.key_block == NULL) {
if (s->session == NULL || s->session->master_key_length == 0) {
/* might happen if dtls1_read_bytes() calls this */
SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, SSL_R_CCS_RECEIVED_EARLY);
return 0;
}
s->session->cipher = s->s3->tmp.new_cipher;
if (!s->method->ssl3_enc->setup_key_block(s))
return 0;
}
if (!s->method->ssl3_enc->change_cipher_state(s, i))
return 0;
return 1;
}
int ssl3_send_alert(SSL *s, int level, int desc)
{
/* Map tls/ssl alert value to correct one */
if (SSL_TREAT_AS_TLS13(s))
desc = tls13_alert_code(desc);
else
desc = s->method->ssl3_enc->alert_value(desc);
if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have
* protocol_version alerts */
if (desc < 0)
return -1;
/* If a fatal one, remove from cache */
if ((level == SSL3_AL_FATAL) && (s->session != NULL))
SSL_CTX_remove_session(s->session_ctx, s->session);
s->s3->alert_dispatch = 1;
s->s3->send_alert[0] = level;
s->s3->send_alert[1] = desc;
if (!RECORD_LAYER_write_pending(&s->rlayer)) {
/* data still being written out? */
return s->method->ssl_dispatch_alert(s);
}
/*
* else data is still being written out, we will get written some time in
* the future
*/
return -1;
}
int ssl3_dispatch_alert(SSL *s)
{
int i, j;
size_t alertlen;
void (*cb) (const SSL *ssl, int type, int val) = NULL;
size_t written;
s->s3->alert_dispatch = 0;
alertlen = 2;
i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], &alertlen, 1, 0,
&written);
if (i <= 0) {
s->s3->alert_dispatch = 1;
} else {
/*
* Alert sent to BIO - now flush. If the message does not get sent due
* to non-blocking IO, we will not worry too much.
*/
(void)BIO_flush(s->wbio);
if (s->msg_callback)
s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
2, s, s->msg_callback_arg);
if (s->info_callback != NULL)
cb = s->info_callback;
else if (s->ctx->info_callback != NULL)
cb = s->ctx->info_callback;
if (cb != NULL) {
j = (s->s3->send_alert[0] << 8) | s->s3->send_alert[1];
cb(s, SSL_CB_WRITE_ALERT, j);
}
}
return i;
}