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/*
* Copyright 2015-2018 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
*/
/*****************************************************************************
* *
* These enums should be considered PRIVATE to the state machine. No *
* non-state machine code should need to use these *
* *
*****************************************************************************/
/*
* Valid return codes used for functions performing work prior to or after
* sending or receiving a message
*/
typedef enum {
/* Something went wrong */
WORK_ERROR,
/* We're done working and there shouldn't be anything else to do after */
WORK_FINISHED_STOP,
/* We're done working move onto the next thing */
WORK_FINISHED_CONTINUE,
/* We're working on phase A */
WORK_MORE_A,
/* We're working on phase B */
WORK_MORE_B,
/* We're working on phase C */
WORK_MORE_C
} WORK_STATE;
/* Write transition return codes */
typedef enum {
/* Something went wrong */
WRITE_TRAN_ERROR,
/* A transition was successfully completed and we should continue */
WRITE_TRAN_CONTINUE,
/* There is no more write work to be done */
WRITE_TRAN_FINISHED
} WRITE_TRAN;
/* Message flow states */
typedef enum {
/* No handshake in progress */
MSG_FLOW_UNINITED,
/* A permanent error with this connection */
MSG_FLOW_ERROR,
/* We are reading messages */
MSG_FLOW_READING,
/* We are writing messages */
MSG_FLOW_WRITING,
/* Handshake has finished */
MSG_FLOW_FINISHED
} MSG_FLOW_STATE;
/* Read states */
typedef enum {
READ_STATE_HEADER,
READ_STATE_BODY,
READ_STATE_POST_PROCESS
} READ_STATE;
/* Write states */
typedef enum {
WRITE_STATE_TRANSITION,
WRITE_STATE_PRE_WORK,
WRITE_STATE_SEND,
WRITE_STATE_POST_WORK
} WRITE_STATE;
typedef enum {
/* The enc_write_ctx can be used normally */
ENC_WRITE_STATE_VALID,
/* The enc_write_ctx cannot be used */
ENC_WRITE_STATE_INVALID,
/* Write alerts in plaintext, but otherwise use the enc_write_ctx */
ENC_WRITE_STATE_WRITE_PLAIN_ALERTS
} ENC_WRITE_STATES;
typedef enum {
/* The enc_read_ctx can be used normally */
ENC_READ_STATE_VALID,
/* We may receive encrypted or plaintext alerts */
ENC_READ_STATE_ALLOW_PLAIN_ALERTS
} ENC_READ_STATES;
/*****************************************************************************
* *
* This structure should be considered "opaque" to anything outside of the *
* state machine. No non-state machine code should be accessing the members *
* of this structure. *
* *
*****************************************************************************/
struct ossl_statem_st {
MSG_FLOW_STATE state;
WRITE_STATE write_state;
WORK_STATE write_state_work;
READ_STATE read_state;
WORK_STATE read_state_work;
OSSL_HANDSHAKE_STATE hand_state;
/* The handshake state requested by an API call (e.g. HelloRequest) */
OSSL_HANDSHAKE_STATE request_state;
int in_init;
int read_state_first_init;
/* true when we are actually in SSL_accept() or SSL_connect() */
int in_handshake;
/*
* True when are processing a "real" handshake that needs cleaning up (not
* just a HelloRequest or similar).
*/
int cleanuphand;
/* Should we skip the CertificateVerify message? */
unsigned int no_cert_verify;
int use_timer;
ENC_WRITE_STATES enc_write_state;
ENC_READ_STATES enc_read_state;
};
typedef struct ossl_statem_st OSSL_STATEM;
/*****************************************************************************
* *
* The following macros/functions represent the libssl internal API to the *
* state machine. Any libssl code may call these functions/macros *
* *
*****************************************************************************/
__owur int ossl_statem_accept(SSL *s);
__owur int ossl_statem_connect(SSL *s);
void ossl_statem_clear(SSL *s);
void ossl_statem_set_renegotiate(SSL *s);
void ossl_statem_fatal(SSL *s, int al, int func, int reason, const char *file,
int line);
# define SSL_AD_NO_ALERT -1
# ifndef OPENSSL_NO_ERR
# define SSLfatal(s, al, f, r) ossl_statem_fatal((s), (al), (f), (r), \
OPENSSL_FILE, OPENSSL_LINE)
# else
# define SSLfatal(s, al, f, r) ossl_statem_fatal((s), (al), (f), (r), NULL, 0)
# endif
int ossl_statem_in_error(const SSL *s);
void ossl_statem_set_in_init(SSL *s, int init);
int ossl_statem_get_in_handshake(SSL *s);
void ossl_statem_set_in_handshake(SSL *s, int inhand);
__owur int ossl_statem_skip_early_data(SSL *s);
void ossl_statem_check_finish_init(SSL *s, int send);
void ossl_statem_set_hello_verify_done(SSL *s);
__owur int ossl_statem_app_data_allowed(SSL *s);
__owur int ossl_statem_export_allowed(SSL *s);
__owur int ossl_statem_export_early_allowed(SSL *s);
/* Flush the write BIO */
int statem_flush(SSL *s);
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