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 typedef enum { 75 /* The enc_write_ctx can be used normally */ 76 ENC_WRITE_STATE_VALID, 77 /* The enc_write_ctx cannot be used */ 78 ENC_WRITE_STATE_INVALID, 79 /* Write alerts in plaintext, but otherwise use the enc_write_ctx */ 80 ENC_WRITE_STATE_WRITE_PLAIN_ALERTS 81 } ENC_WRITE_STATES; 82 83 typedef enum { 84 /* The enc_read_ctx can be used normally */ 85 ENC_READ_STATE_VALID, 86 /* We may receive encrypted or plaintext alerts */ 87 ENC_READ_STATE_ALLOW_PLAIN_ALERTS 88 } ENC_READ_STATES; 89 90 /***************************************************************************** 91 * * 92 * This structure should be considered "opaque" to anything outside of the * 93 * state machine. No non-state machine code should be accessing the members * 94 * of this structure. * 95 * * 96 *****************************************************************************/ 97 98 struct ossl_statem_st { 99 MSG_FLOW_STATE state; 100 WRITE_STATE write_state; 101 WORK_STATE write_state_work; 102 READ_STATE read_state; 103 WORK_STATE read_state_work; 104 OSSL_HANDSHAKE_STATE hand_state; 105 /* The handshake state requested by an API call (e.g. HelloRequest) */ 106 OSSL_HANDSHAKE_STATE request_state; 107 int in_init; 108 int read_state_first_init; 109 /* true when we are actually in SSL_accept() or SSL_connect() */ 110 int in_handshake; 111 /* 112 * True when are processing a "real" handshake that needs cleaning up (not 113 * just a HelloRequest or similar). 114 */ 115 int cleanuphand; 116 /* Should we skip the CertificateVerify message? */ 117 unsigned int no_cert_verify; 118 int use_timer; 119 ENC_WRITE_STATES enc_write_state; 120 ENC_READ_STATES enc_read_state; 121 }; 122 typedef struct ossl_statem_st OSSL_STATEM; 123 124 /***************************************************************************** 125 * * 126 * The following macros/functions represent the libssl internal API to the * 127 * state machine. Any libssl code may call these functions/macros * 128 * * 129 *****************************************************************************/ 130 131 __owur int ossl_statem_accept(SSL *s); 132 __owur int ossl_statem_connect(SSL *s); 133 void ossl_statem_clear(SSL *s); 134 void ossl_statem_set_renegotiate(SSL *s); 135 void ossl_statem_fatal(SSL *s, int al, int func, int reason, const char *file, 136 int line); 137 # define SSL_AD_NO_ALERT -1 138 # ifndef OPENSSL_NO_ERR 139 # define SSLfatal(s, al, f, r) ossl_statem_fatal((s), (al), (f), (r), \ 140 OPENSSL_FILE, OPENSSL_LINE) 141 # else 142 # define SSLfatal(s, al, f, r) ossl_statem_fatal((s), (al), (f), (r), NULL, 0) 143 # endif 144 145 int ossl_statem_in_error(const SSL *s); 146 void ossl_statem_set_in_init(SSL *s, int init); 147 int ossl_statem_get_in_handshake(SSL *s); 148 void ossl_statem_set_in_handshake(SSL *s, int inhand); 149 __owur int ossl_statem_skip_early_data(SSL *s); 150 void ossl_statem_check_finish_init(SSL *s, int send); 151 void ossl_statem_set_hello_verify_done(SSL *s); 152 __owur int ossl_statem_app_data_allowed(SSL *s); 153 __owur int ossl_statem_export_allowed(SSL *s); 154 __owur int ossl_statem_export_early_allowed(SSL *s); 155 156 /* Flush the write BIO */ 157 int statem_flush(SSL *s); 158