openssl/ssl/statem/statem_locl.h
Matt Caswell 6b473acabd Refactor ClientHello extension parsing
This builds on the work started in 1ab3836b3 and extends is so that
each extension has its own identified parsing functions, as well as an
allowed context identifying which messages and protocols it is relevant for.
Subsequent commits will do a similar job for the ServerHello extensions.
This will enable us to have common functions for processing extension blocks
no matter which of the multiple messages they are received from. In TLSv1.3
a number of different messages have extension blocks, and some extensions
have moved from one message to another when compared to TLSv1.2.

Perl changes reviewed by Richard Levitte. Non-perl changes reviewed by Rich
Salz

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
2016-12-08 17:17:45 +00:00

155 lines
7.4 KiB
C

/*
* Copyright 2015-2016 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
*/
/*****************************************************************************
* *
* The following definitions are PRIVATE to the state machine. They should *
* NOT be used outside of the state machine. *
* *
*****************************************************************************/
/* Max message length definitions */
/* The spec allows for a longer length than this, but we limit it */
#define HELLO_VERIFY_REQUEST_MAX_LENGTH 258
#define SERVER_HELLO_MAX_LENGTH 20000
#define ENCRYPTED_EXTENSIONS_MAX_LENGTH 20000
#define SERVER_KEY_EXCH_MAX_LENGTH 102400
#define SERVER_HELLO_DONE_MAX_LENGTH 0
#define CCS_MAX_LENGTH 1
/* Max should actually be 36 but we are generous */
#define FINISHED_MAX_LENGTH 64
/* Extension context codes */
#define EXT_TLS_ONLY 0x0001
#define EXT_DTLS_ONLY 0x0002
/* Some extensions may be allowed in DTLS but we don't implement them for it */
#define EXT_TLS_IMPLEMENTATION_ONLY 0x0004
/* Most extensions are not defined for SSLv3 but EXT_TYPE_renegotiate is */
#define EXT_SSL3_ALLOWED 0x0008
#define EXT_TLS1_2_AND_BELOW_ONLY 0x0010
#define EXT_TLS1_3_ONLY 0x0020
#define EXT_CLIENT_HELLO 0x0040
/* Really means TLS1.2 or below */
#define EXT_TLS1_2_SERVER_HELLO 0x0080
#define EXT_TLS1_3_SERVER_HELLO 0x0100
#define EXT_TLS1_3_ENCRYPTED_EXTENSIONS 0x0200
#define EXT_TLS1_3_HELLO_RETRY_REQUEST 0x0400
#define EXT_TLS1_3_CERTIFICATE 0x0800
#define EXT_TLS1_3_NEW_SESSION_TICKET 0x1000
/* Message processing return codes */
typedef enum {
/* Something bad happened */
MSG_PROCESS_ERROR,
/* We've finished reading - swap to writing */
MSG_PROCESS_FINISHED_READING,
/*
* We've completed the main processing of this message but there is some
* post processing to be done.
*/
MSG_PROCESS_CONTINUE_PROCESSING,
/* We've finished this message - read the next message */
MSG_PROCESS_CONTINUE_READING
} MSG_PROCESS_RETURN;
/* Flush the write BIO */
int statem_flush(SSL *s);
typedef int (*confunc_f) (SSL *s, WPACKET *pkt);
/*
* TLS/DTLS client state machine functions
*/
int ossl_statem_client_read_transition(SSL *s, int mt);
WRITE_TRAN ossl_statem_client_write_transition(SSL *s);
WORK_STATE ossl_statem_client_pre_work(SSL *s, WORK_STATE wst);
WORK_STATE ossl_statem_client_post_work(SSL *s, WORK_STATE wst);
int ossl_statem_client_construct_message(SSL *s, WPACKET *pkt,
confunc_f *confunc, int *mt);
size_t ossl_statem_client_max_message_size(SSL *s);
MSG_PROCESS_RETURN ossl_statem_client_process_message(SSL *s, PACKET *pkt);
WORK_STATE ossl_statem_client_post_process_message(SSL *s, WORK_STATE wst);
/*
* TLS/DTLS server state machine functions
*/
int ossl_statem_server_read_transition(SSL *s, int mt);
WRITE_TRAN ossl_statem_server_write_transition(SSL *s);
WORK_STATE ossl_statem_server_pre_work(SSL *s, WORK_STATE wst);
WORK_STATE ossl_statem_server_post_work(SSL *s, WORK_STATE wst);
int ossl_statem_server_construct_message(SSL *s, WPACKET *pkt,
confunc_f *confunc,int *mt);
size_t ossl_statem_server_max_message_size(SSL *s);
MSG_PROCESS_RETURN ossl_statem_server_process_message(SSL *s, PACKET *pkt);
WORK_STATE ossl_statem_server_post_process_message(SSL *s, WORK_STATE wst);
/* Functions for getting new message data */
__owur int tls_get_message_header(SSL *s, int *mt);
__owur int tls_get_message_body(SSL *s, size_t *len);
__owur int dtls_get_message(SSL *s, int *mt, size_t *len);
/* Message construction and processing functions */
__owur int tls_process_initial_server_flight(SSL *s, int *al);
__owur MSG_PROCESS_RETURN tls_process_change_cipher_spec(SSL *s, PACKET *pkt);
__owur MSG_PROCESS_RETURN tls_process_finished(SSL *s, PACKET *pkt);
__owur int tls_construct_change_cipher_spec(SSL *s, WPACKET *pkt);
__owur int dtls_construct_change_cipher_spec(SSL *s, WPACKET *pkt);
__owur int tls_construct_finished(SSL *s, WPACKET *pkt);
__owur WORK_STATE tls_finish_handshake(SSL *s, WORK_STATE wst);
__owur WORK_STATE dtls_wait_for_dry(SSL *s);
int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context,
RAW_EXTENSION **res, size_t *numfound, int *ad);
/* some client-only functions */
__owur int tls_construct_client_hello(SSL *s, WPACKET *pkt);
__owur MSG_PROCESS_RETURN tls_process_server_hello(SSL *s, PACKET *pkt);
__owur MSG_PROCESS_RETURN tls_process_certificate_request(SSL *s, PACKET *pkt);
__owur MSG_PROCESS_RETURN tls_process_new_session_ticket(SSL *s, PACKET *pkt);
__owur MSG_PROCESS_RETURN tls_process_cert_status(SSL *s, PACKET *pkt);
__owur MSG_PROCESS_RETURN tls_process_server_done(SSL *s, PACKET *pkt);
__owur int tls_construct_client_verify(SSL *s, WPACKET *pkt);
__owur WORK_STATE tls_prepare_client_certificate(SSL *s, WORK_STATE wst);
__owur int tls_construct_client_certificate(SSL *s, WPACKET *pkt);
__owur int ssl_do_client_cert_cb(SSL *s, X509 **px509, EVP_PKEY **ppkey);
__owur int tls_construct_client_key_exchange(SSL *s, WPACKET *pkt);
__owur int tls_client_key_exchange_post_work(SSL *s);
__owur int tls_construct_cert_status(SSL *s, WPACKET *pkt);
__owur MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt);
__owur MSG_PROCESS_RETURN tls_process_server_certificate(SSL *s, PACKET *pkt);
__owur int ssl3_check_cert_and_algorithm(SSL *s);
#ifndef OPENSSL_NO_NEXTPROTONEG
__owur int tls_construct_next_proto(SSL *s, WPACKET *pkt);
#endif
__owur MSG_PROCESS_RETURN dtls_process_hello_verify(SSL *s, PACKET *pkt);
/* some server-only functions */
__owur MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt);
__owur WORK_STATE tls_post_process_client_hello(SSL *s, WORK_STATE wst);
__owur int tls_construct_server_hello(SSL *s, WPACKET *pkt);
__owur int dtls_construct_hello_verify_request(SSL *s, WPACKET *pkt);
__owur int tls_construct_server_certificate(SSL *s, WPACKET *pkt);
__owur int tls_construct_server_key_exchange(SSL *s, WPACKET *pkt);
__owur int tls_construct_certificate_request(SSL *s, WPACKET *pkt);
__owur int tls_construct_server_done(SSL *s, WPACKET *pkt);
__owur MSG_PROCESS_RETURN tls_process_client_certificate(SSL *s, PACKET *pkt);
__owur MSG_PROCESS_RETURN tls_process_client_key_exchange(SSL *s, PACKET *pkt);
__owur WORK_STATE tls_post_process_client_key_exchange(SSL *s, WORK_STATE wst);
__owur MSG_PROCESS_RETURN tls_process_cert_verify(SSL *s, PACKET *pkt);
#ifndef OPENSSL_NO_NEXTPROTONEG
__owur MSG_PROCESS_RETURN tls_process_next_proto(SSL *s, PACKET *pkt);
#endif
__owur int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt);
__owur int tls_parse_all_extensions(SSL *s, RAW_EXTENSION *exts, size_t numexts,
int *al);
__owur int tls_parse_extension(SSL *s, int type, RAW_EXTENSION *exts,
size_t numexts, int *al);