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* Copyright 2016-2017 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 <openssl/ocsp.h>
#include "../ssl_locl.h"
#include "statem_locl.h"
/*
* Parse the client's renegotiation binding and abort if it's not right
*/
int tls_parse_ctos_renegotiate(SSL *s, PACKET *pkt, unsigned int context,
X509 *x, size_t chainidx, int *al)
{
unsigned int ilen;
const unsigned char *data;
/* Parse the length byte */
if (!PACKET_get_1(pkt, &ilen)
|| !PACKET_get_bytes(pkt, &data, ilen)) {
SSL_R_RENEGOTIATION_ENCODING_ERR);
*al = SSL_AD_ILLEGAL_PARAMETER;
return 0;
}
/* Check that the extension matches */
if (ilen != s->s3->previous_client_finished_len) {
SSL_R_RENEGOTIATION_MISMATCH);
*al = SSL_AD_HANDSHAKE_FAILURE;
return 0;
}
if (memcmp(data, s->s3->previous_client_finished,
s->s3->previous_client_finished_len)) {
SSL_R_RENEGOTIATION_MISMATCH);
*al = SSL_AD_HANDSHAKE_FAILURE;
return 0;
}
s->s3->send_connection_binding = 1;
return 1;
}
/*-
* The servername extension is treated as follows:
*
* - Only the hostname type is supported with a maximum length of 255.
* - The servername is rejected if too long or if it contains zeros,
* in which case an fatal alert is generated.
* - The servername field is maintained together with the session cache.
* - When a session is resumed, the servername call back invoked in order
* to allow the application to position itself to the right context.
* - The servername is acknowledged if it is new for a session or when
* it is identical to a previously used for the same session.
* Applications can control the behaviour. They can at any time
* set a 'desirable' servername for a new SSL object. This can be the
* case for example with HTTPS when a Host: header field is received and
* a renegotiation is requested. In this case, a possible servername
* presented in the new client hello is only acknowledged if it matches
* the value of the Host: field.
* - Applications must use SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
* if they provide for changing an explicit servername context for the
* session, i.e. when the session has been established with a servername
* extension.
* - On session reconnect, the servername extension may be absent.
*/
int tls_parse_ctos_server_name(SSL *s, PACKET *pkt, unsigned int context,
X509 *x, size_t chainidx, int *al)
{
unsigned int servname_type;
PACKET sni, hostname;
if (!PACKET_as_length_prefixed_2(pkt, &sni)
/* ServerNameList must be at least 1 byte long. */
|| PACKET_remaining(&sni) == 0) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
/*
* Although the server_name extension was intended to be
* extensible to new name types, RFC 4366 defined the
* syntax inextensibly and OpenSSL 1.0.x parses it as
* such.
* RFC 6066 corrected the mistake but adding new name types
* is nevertheless no longer feasible, so act as if no other
* SNI types can exist, to simplify parsing.
*
* Also note that the RFC permits only one SNI value per type,
* i.e., we can only have a single hostname.
*/
if (!PACKET_get_1(&sni, &servname_type)
|| servname_type != TLSEXT_NAMETYPE_host_name
|| !PACKET_as_length_prefixed_2(&sni, &hostname)) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (!s->hit) {
if (PACKET_remaining(&hostname) > TLSEXT_MAXLEN_host_name) {
*al = TLS1_AD_UNRECOGNIZED_NAME;
return 0;
}
if (PACKET_contains_zero_byte(&hostname)) {
*al = TLS1_AD_UNRECOGNIZED_NAME;
return 0;
}
OPENSSL_free(s->session->ext.hostname);
s->session->ext.hostname = NULL;
if (!PACKET_strndup(&hostname, &s->session->ext.hostname)) {
*al = TLS1_AD_INTERNAL_ERROR;
return 0;
}
s->servername_done = 1;
} else {
/*
* TODO(openssl-team): if the SNI doesn't match, we MUST
* fall back to a full handshake.
*/
s->servername_done = s->session->ext.hostname
&& PACKET_equal(&hostname, s->session->ext.hostname,
strlen(s->session->ext.hostname));
}
return 1;
}
#ifndef OPENSSL_NO_SRP
int tls_parse_ctos_srp(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
size_t chainidx, int *al)
{
PACKET srp_I;
if (!PACKET_as_length_prefixed_1(pkt, &srp_I)
|| PACKET_contains_zero_byte(&srp_I)) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
/*
* TODO(openssl-team): currently, we re-authenticate the user
* upon resumption. Instead, we MUST ignore the login.
*/
if (!PACKET_strndup(&srp_I, &s->srp_ctx.login)) {
*al = TLS1_AD_INTERNAL_ERROR;
return 0;
}
return 1;
}
#endif
#ifndef OPENSSL_NO_EC
int tls_parse_ctos_ec_pt_formats(SSL *s, PACKET *pkt, unsigned int context,
X509 *x, size_t chainidx, int *al)
{
PACKET ec_point_format_list;
if (!PACKET_as_length_prefixed_1(pkt, &ec_point_format_list)
|| PACKET_remaining(&ec_point_format_list) == 0) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (!s->hit) {
if (!PACKET_memdup(&ec_point_format_list,
&s->session->ext.ecpointformats,
&s->session->ext.ecpointformats_len)) {
*al = TLS1_AD_INTERNAL_ERROR;
return 0;
}
}
return 1;
}
#endif /* OPENSSL_NO_EC */
int tls_parse_ctos_session_ticket(SSL *s, PACKET *pkt, unsigned int context,
X509 *x, size_t chainidx, int *al)
if (s->ext.session_ticket_cb &&
!s->ext.session_ticket_cb(s, PACKET_data(pkt),
PACKET_remaining(pkt),
s->ext.session_ticket_cb_arg)) {
*al = TLS1_AD_INTERNAL_ERROR;
return 0;
}
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