ssl/statem/statem.h

   1 /*
   2  * Copyright 2015-2018 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 /*****************************************************************************
  11  *                                                                           *
  12  * These enums should be considered PRIVATE to the state machine. No         *
  13  * non-state machine code should need to use these                           *
  14  *                                                                           *
  15  *****************************************************************************/
  16 /*
  17  * Valid return codes used for functions performing work prior to or after
  18  * sending or receiving a message
  19  */
  20 typedef enum {
  21     /* Something went wrong */
  22     WORK_ERROR,
  23     /* We're done working and there shouldn't be anything else to do after */
  24     WORK_FINISHED_STOP,
  25     /* We're done working move onto the next thing */
  26     WORK_FINISHED_CONTINUE,
  27     /* We're working on phase A */
  28     WORK_MORE_A,
  29     /* We're working on phase B */
  30     WORK_MORE_B,
  31     /* We're working on phase C */
  32     WORK_MORE_C
  33 } WORK_STATE;
  34
  35 /* Write transition return codes */
  36 typedef enum {
  37     /* Something went wrong */
  38     WRITE_TRAN_ERROR,
  39     /* A transition was successfully completed and we should continue */
  40     WRITE_TRAN_CONTINUE,
  41     /* There is no more write work to be done */
  42     WRITE_TRAN_FINISHED
  43 } WRITE_TRAN;
  44
  45 /* Message flow states */
  46 typedef enum {
  47     /* No handshake in progress */
  48     MSG_FLOW_UNINITED,
  49     /* A permanent error with this connection */
  50     MSG_FLOW_ERROR,
  51     /* We are reading messages */
  52     MSG_FLOW_READING,
  53     /* We are writing messages */
  54     MSG_FLOW_WRITING,
  55     /* Handshake has finished */
  56     MSG_FLOW_FINISHED
  57 } MSG_FLOW_STATE;
  58
  59 /* Read states */
  60 typedef enum {
  61     READ_STATE_HEADER,
  62     READ_STATE_BODY,
  63     READ_STATE_POST_PROCESS
  64 } READ_STATE;
  65
  66 /* Write states */
  67 typedef enum {
  68     WRITE_STATE_TRANSITION,
  69     WRITE_STATE_PRE_WORK,
  70     WRITE_STATE_SEND,
  71     WRITE_STATE_POST_WORK
  72 } WRITE_STATE;
  73
  74 /*****************************************************************************
  75  *                                                                           *
  76  * This structure should be considered "opaque" to anything outside of the   *
  77  * state machine. No non-state machine code should be accessing the members  *
  78  * of this structure.                                                        *
  79  *                                                                           *
  80  *****************************************************************************/
  81
  82 struct ossl_statem_st {
  83     MSG_FLOW_STATE state;
  84     WRITE_STATE write_state;
  85     WORK_STATE write_state_work;
  86     READ_STATE read_state;
  87     WORK_STATE read_state_work;
  88     OSSL_HANDSHAKE_STATE hand_state;
  89     /* The handshake state requested by an API call (e.g. HelloRequest) */
  90     OSSL_HANDSHAKE_STATE request_state;
  91     int in_init;
  92     int read_state_first_init;
  93     /* true when we are actually in SSL_accept() or SSL_connect() */
  94     int in_handshake;
  95     /*
  96      * True when are processing a "real" handshake that needs cleaning up (not
  97      * just a HelloRequest or similar).
  98      */
  99     int cleanuphand;
 100     /* Should we skip the CertificateVerify message? */
 101     unsigned int no_cert_verify;
 102     int use_timer;
 103     int invalid_enc_write_ctx;
 104 };
 105 typedef struct ossl_statem_st OSSL_STATEM;
 106
 107 /*****************************************************************************
 108  *                                                                           *
 109  * The following macros/functions represent the libssl internal API to the   *
 110  * state machine. Any libssl code may call these functions/macros            *
 111  *                                                                           *
 112  *****************************************************************************/
 113
 114 __owur int ossl_statem_accept(SSL *s);
 115 __owur int ossl_statem_connect(SSL *s);
 116 void ossl_statem_clear(SSL *s);
 117 void ossl_statem_set_renegotiate(SSL *s);
 118 void ossl_statem_fatal(SSL *s, int al, int func, int reason, const char *file,
 119                        int line);
 120 # define SSL_AD_NO_ALERT    -1
 121 # ifndef OPENSSL_NO_ERR
 122 #  define SSLfatal(s, al, f, r)  ossl_statem_fatal((s), (al), (f), (r), \
 123                                                    OPENSSL_FILE, OPENSSL_LINE)
 124 # else
 125 #  define SSLfatal(s, al, f, r)  ossl_statem_fatal((s), (al), (f), (r), NULL, 0)
 126 # endif
 127
 128 int ossl_statem_in_error(const SSL *s);
 129 void ossl_statem_set_in_init(SSL *s, int init);
 130 int ossl_statem_get_in_handshake(SSL *s);
 131 void ossl_statem_set_in_handshake(SSL *s, int inhand);
 132 __owur int ossl_statem_skip_early_data(SSL *s);
 133 void ossl_statem_check_finish_init(SSL *s, int send);
 134 void ossl_statem_set_hello_verify_done(SSL *s);
 135 __owur int ossl_statem_app_data_allowed(SSL *s);
 136 __owur int ossl_statem_export_allowed(SSL *s);
 137 __owur int ossl_statem_export_early_allowed(SSL *s);
 138
 139 /* Flush the write BIO */
 140 int statem_flush(SSL *s);