ssl/statem/statem_locl.h

   1 /*
   2  * Copyright 2015-2016 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  * The following definitions are PRIVATE to the state machine. They should   *
  13  * NOT be used outside of the state machine.                                 *
  14  *                                                                           *
  15  *****************************************************************************/
  16
  17 /* Max message length definitions */
  18
  19 /* The spec allows for a longer length than this, but we limit it */
  20 #define HELLO_VERIFY_REQUEST_MAX_LENGTH 258
  21 #define END_OF_EARLY_DATA_MAX_LENGTH    0
  22 #define SERVER_HELLO_MAX_LENGTH         20000
  23 #define HELLO_RETRY_REQUEST_MAX_LENGTH  20000
  24 #define ENCRYPTED_EXTENSIONS_MAX_LENGTH 20000
  25 #define SERVER_KEY_EXCH_MAX_LENGTH      102400
  26 #define SERVER_HELLO_DONE_MAX_LENGTH    0
  27 #define KEY_UPDATE_MAX_LENGTH           1
  28 #define CCS_MAX_LENGTH                  1
  29 /* Max should actually be 36 but we are generous */
  30 #define FINISHED_MAX_LENGTH             64
  31
  32 /* The maximum number of incoming KeyUpdate messages we will accept */
  33 #define MAX_KEY_UPDATE_MESSAGES     32
  34
  35 /* Dummy message type */
  36 #define SSL3_MT_DUMMY   -1
  37
  38 /* Message processing return codes */
  39 typedef enum {
  40     /* Something bad happened */
  41     MSG_PROCESS_ERROR,
  42     /* We've finished reading - swap to writing */
  43     MSG_PROCESS_FINISHED_READING,
  44     /*
  45      * We've completed the main processing of this message but there is some
  46      * post processing to be done.
  47      */
  48     MSG_PROCESS_CONTINUE_PROCESSING,
  49     /* We've finished this message - read the next message */
  50     MSG_PROCESS_CONTINUE_READING
  51 } MSG_PROCESS_RETURN;
  52
  53 /* Flush the write BIO */
  54 int statem_flush(SSL *s);
  55
  56 typedef int (*confunc_f) (SSL *s, WPACKET *pkt);
  57
  58 #define GET_GROUP_ID(group, idx) \
  59     (unsigned int)(((group)[(idx) * 2] << 8) | (group)[((idx) * 2) + 1])
  60
  61 int check_in_list(SSL *s, unsigned int group_id, const unsigned char *groups,
  62                   size_t num_groups, int checkallow);
  63 int create_synthetic_message_hash(SSL *s);
  64 int parse_ca_names(SSL *s, PACKET *pkt, int *al);
  65 int construct_ca_names(SSL *s, WPACKET *pkt);
  66
  67 /*
  68  * TLS/DTLS client state machine functions
  69  */
  70 int ossl_statem_client_read_transition(SSL *s, int mt);
  71 WRITE_TRAN ossl_statem_client_write_transition(SSL *s);
  72 WORK_STATE ossl_statem_client_pre_work(SSL *s, WORK_STATE wst);
  73 WORK_STATE ossl_statem_client_post_work(SSL *s, WORK_STATE wst);
  74 int ossl_statem_client_construct_message(SSL *s, WPACKET *pkt,
  75                                          confunc_f *confunc, int *mt);
  76 size_t ossl_statem_client_max_message_size(SSL *s);
  77 MSG_PROCESS_RETURN ossl_statem_client_process_message(SSL *s, PACKET *pkt);
  78 WORK_STATE ossl_statem_client_post_process_message(SSL *s, WORK_STATE wst);
  79
  80 /*
  81  * TLS/DTLS server state machine functions
  82  */
  83 int ossl_statem_server_read_transition(SSL *s, int mt);
  84 WRITE_TRAN ossl_statem_server_write_transition(SSL *s);
  85 WORK_STATE ossl_statem_server_pre_work(SSL *s, WORK_STATE wst);
  86 WORK_STATE ossl_statem_server_post_work(SSL *s, WORK_STATE wst);
  87 int ossl_statem_server_construct_message(SSL *s, WPACKET *pkt,
  88                                          confunc_f *confunc,int *mt);
  89 size_t ossl_statem_server_max_message_size(SSL *s);
  90 MSG_PROCESS_RETURN ossl_statem_server_process_message(SSL *s, PACKET *pkt);
  91 WORK_STATE ossl_statem_server_post_process_message(SSL *s, WORK_STATE wst);
  92
  93 /* Functions for getting new message data */
  94 __owur int tls_get_message_header(SSL *s, int *mt);
  95 __owur int tls_get_message_body(SSL *s, size_t *len);
  96 __owur int dtls_get_message(SSL *s, int *mt, size_t *len);
  97
  98 /* Message construction and processing functions */
  99 __owur int tls_process_initial_server_flight(SSL *s, int *al);
 100 __owur MSG_PROCESS_RETURN tls_process_change_cipher_spec(SSL *s, PACKET *pkt);
 101 __owur MSG_PROCESS_RETURN tls_process_finished(SSL *s, PACKET *pkt);
 102 __owur int tls_construct_change_cipher_spec(SSL *s, WPACKET *pkt);
 103 __owur int dtls_construct_change_cipher_spec(SSL *s, WPACKET *pkt);
 104
 105 __owur int tls_construct_finished(SSL *s, WPACKET *pkt);
 106 __owur int tls_construct_key_update(SSL *s, WPACKET *pkt);
 107 __owur MSG_PROCESS_RETURN tls_process_key_update(SSL *s, PACKET *pkt);
 108 __owur WORK_STATE tls_finish_handshake(SSL *s, WORK_STATE wst, int clearbufs);
 109 __owur WORK_STATE dtls_wait_for_dry(SSL *s);
 110
 111 /* some client-only functions */
 112 __owur int tls_construct_client_hello(SSL *s, WPACKET *pkt);
 113 __owur MSG_PROCESS_RETURN tls_process_server_hello(SSL *s, PACKET *pkt);
 114 __owur MSG_PROCESS_RETURN tls_process_certificate_request(SSL *s, PACKET *pkt);
 115 __owur MSG_PROCESS_RETURN tls_process_new_session_ticket(SSL *s, PACKET *pkt);
 116 __owur int tls_process_cert_status_body(SSL *s, PACKET *pkt, int *al);
 117 __owur MSG_PROCESS_RETURN tls_process_cert_status(SSL *s, PACKET *pkt);
 118 __owur MSG_PROCESS_RETURN tls_process_server_done(SSL *s, PACKET *pkt);
 119 __owur int tls_construct_cert_verify(SSL *s, WPACKET *pkt);
 120 __owur WORK_STATE tls_prepare_client_certificate(SSL *s, WORK_STATE wst);
 121 __owur int tls_construct_client_certificate(SSL *s, WPACKET *pkt);
 122 __owur int ssl_do_client_cert_cb(SSL *s, X509 **px509, EVP_PKEY **ppkey);
 123 __owur int tls_construct_client_key_exchange(SSL *s, WPACKET *pkt);
 124 __owur int tls_client_key_exchange_post_work(SSL *s);
 125 __owur int tls_construct_cert_status_body(SSL *s, WPACKET *pkt);
 126 __owur int tls_construct_cert_status(SSL *s, WPACKET *pkt);
 127 __owur MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt);
 128 __owur MSG_PROCESS_RETURN tls_process_server_certificate(SSL *s, PACKET *pkt);
 129 __owur int ssl3_check_cert_and_algorithm(SSL *s);
 130 #ifndef OPENSSL_NO_NEXTPROTONEG
 131 __owur int tls_construct_next_proto(SSL *s, WPACKET *pkt);
 132 #endif
 133 __owur MSG_PROCESS_RETURN tls_process_hello_req(SSL *s, PACKET *pkt);
 134 __owur MSG_PROCESS_RETURN dtls_process_hello_verify(SSL *s, PACKET *pkt);
 135 __owur int tls_construct_end_of_early_data(SSL *s, WPACKET *pkt);
 136
 137 /* some server-only functions */
 138 __owur MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt);
 139 __owur WORK_STATE tls_post_process_client_hello(SSL *s, WORK_STATE wst);
 140 __owur int tls_construct_server_hello(SSL *s, WPACKET *pkt);
 141 __owur int dtls_construct_hello_verify_request(SSL *s, WPACKET *pkt);
 142 __owur int tls_construct_server_certificate(SSL *s, WPACKET *pkt);
 143 __owur int tls_construct_server_key_exchange(SSL *s, WPACKET *pkt);
 144 __owur int tls_construct_certificate_request(SSL *s, WPACKET *pkt);
 145 __owur int tls_construct_server_done(SSL *s, WPACKET *pkt);
 146 __owur MSG_PROCESS_RETURN tls_process_client_certificate(SSL *s, PACKET *pkt);
 147 __owur MSG_PROCESS_RETURN tls_process_client_key_exchange(SSL *s, PACKET *pkt);
 148 __owur WORK_STATE tls_post_process_client_key_exchange(SSL *s, WORK_STATE wst);
 149 __owur MSG_PROCESS_RETURN tls_process_cert_verify(SSL *s, PACKET *pkt);
 150 #ifndef OPENSSL_NO_NEXTPROTONEG
 151 __owur MSG_PROCESS_RETURN tls_process_next_proto(SSL *s, PACKET *pkt);
 152 #endif
 153 __owur int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt);
 154 MSG_PROCESS_RETURN tls_process_end_of_early_data(SSL *s, PACKET *pkt);
 155
 156
 157 /* Extension processing */
 158
 159 typedef enum {
 160     EXT_RETURN_FAIL,
 161     EXT_RETURN_SENT,
 162     EXT_RETURN_NOT_SENT
 163 } EXT_RETURN;
 164
 165 __owur int extension_is_relevant(SSL *s, unsigned int extctx,
 166                                  unsigned int thisctx);
 167 __owur int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context,
 168                                   RAW_EXTENSION **res, int *al, size_t *len,
 169                                   int init);
 170 __owur int tls_parse_extension(SSL *s, TLSEXT_INDEX idx, int context,
 171                                RAW_EXTENSION *exts,  X509 *x, size_t chainidx,
 172                                int *al);
 173 __owur int tls_parse_all_extensions(SSL *s, int context, RAW_EXTENSION *exts,
 174                                     X509 *x, size_t chainidx, int *al, int fin);
 175 __owur int should_add_extension(SSL *s, unsigned int extctx,
 176                                 unsigned int thisctx, int max_version);
 177 __owur int tls_construct_extensions(SSL *s, WPACKET *pkt, unsigned int context,
 178                                     X509 *x, size_t chainidx, int *al);
 179
 180 __owur int tls_psk_do_binder(SSL *s, const EVP_MD *md,
 181                              const unsigned char *msgstart,
 182                              size_t binderoffset, const unsigned char *binderin,
 183                              unsigned char *binderout,
 184                              SSL_SESSION *sess, int sign);
 185
 186 /* Server Extension processing */
 187 int tls_parse_ctos_renegotiate(SSL *s, PACKET *pkt, unsigned int context,
 188                                X509 *x, size_t chainidx, int *al);
 189 int tls_parse_ctos_server_name(SSL *s, PACKET *pkt, unsigned int context,
 190                                X509 *x, size_t chainidx, int *al);
 191 #ifndef OPENSSL_NO_SRP
 192 int tls_parse_ctos_srp(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 193                        size_t chainidx, int *al);
 194 #endif
 195 int tls_parse_ctos_early_data(SSL *s, PACKET *pkt, unsigned int context,
 196                               X509 *x, size_t chainidx, int *al);
 197 #ifndef OPENSSL_NO_EC
 198 int tls_parse_ctos_ec_pt_formats(SSL *s, PACKET *pkt, unsigned int context,
 199                                  X509 *x, size_t chainidx, int *al);
 200 int tls_parse_ctos_supported_groups(SSL *s, PACKET *pkt, unsigned int context,
 201                                     X509 *x, size_t chainidx, int *al);
 202 #endif
 203 int tls_parse_ctos_session_ticket(SSL *s, PACKET *pkt, unsigned int context,
 204                                   X509 *x, size_t chainidx, int *al);
 205 int tls_parse_ctos_sig_algs(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 206                             size_t chainidx, int *al);
 207 #ifndef OPENSSL_NO_OCSP
 208 int tls_parse_ctos_status_request(SSL *s, PACKET *pkt, unsigned int context,
 209                                   X509 *x, size_t chainidx, int *al);
 210 #endif
 211 #ifndef OPENSSL_NO_NEXTPROTONEG
 212 int tls_parse_ctos_npn(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 213                        size_t chainidx, int *al);
 214 #endif
 215 int tls_parse_ctos_alpn(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 216                         size_t chainidx, int *al);
 217 #ifndef OPENSSL_NO_SRTP
 218 int tls_parse_ctos_use_srtp(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 219                             size_t chainidx, int *al);
 220 #endif
 221 int tls_parse_ctos_etm(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 222                        size_t chainidx, int *al);
 223 int tls_parse_ctos_key_share(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 224                              size_t chainidx, int *al);
 225 int tls_parse_ctos_ems(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 226                        size_t chainidx, int *al);
 227 int tls_parse_ctos_psk_kex_modes(SSL *s, PACKET *pkt, unsigned int context,
 228                                  X509 *x, size_t chainidx, int *al);
 229 int tls_parse_ctos_psk(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 230                        size_t chainidx, int *al);
 231
 232 EXT_RETURN tls_construct_stoc_renegotiate(SSL *s, WPACKET *pkt,
 233                                           unsigned int context, X509 *x,
 234                                           size_t chainidx, int *al);
 235 EXT_RETURN tls_construct_stoc_server_name(SSL *s, WPACKET *pkt,
 236                                           unsigned int context, X509 *x,
 237                                           size_t chainidx, int *al);
 238 EXT_RETURN tls_construct_stoc_early_data(SSL *s, WPACKET *pkt,
 239                                          unsigned int context, X509 *x,
 240                                          size_t chainidx, int *al);
 241 #ifndef OPENSSL_NO_EC
 242 EXT_RETURN tls_construct_stoc_ec_pt_formats(SSL *s, WPACKET *pkt,
 243                                             unsigned int context, X509 *x,
 244                                             size_t chainidx, int *al);
 245 #endif
 246 EXT_RETURN tls_construct_stoc_supported_groups(SSL *s, WPACKET *pkt,
 247                                                unsigned int context, X509 *x,
 248                                                size_t chainidx, int *al);
 249 EXT_RETURN tls_construct_stoc_session_ticket(SSL *s, WPACKET *pkt,
 250                                              unsigned int context, X509 *x,
 251                                              size_t chainidx, int *al);
 252 #ifndef OPENSSL_NO_OCSP
 253 EXT_RETURN tls_construct_stoc_status_request(SSL *s, WPACKET *pkt,
 254                                              unsigned int context, X509 *x,
 255                                              size_t chainidx, int *al);
 256 #endif
 257 #ifndef OPENSSL_NO_NEXTPROTONEG
 258 EXT_RETURN tls_construct_stoc_next_proto_neg(SSL *s, WPACKET *pkt,
 259                                              unsigned int context, X509 *x,
 260                                              size_t chainidx, int *al);
 261 #endif
 262 EXT_RETURN tls_construct_stoc_alpn(SSL *s, WPACKET *pkt, unsigned int context,
 263                                    X509 *x, size_t chainidx, int *al);
 264 #ifndef OPENSSL_NO_SRTP
 265 EXT_RETURN tls_construct_stoc_use_srtp(SSL *s, WPACKET *pkt, unsigned int context,
 266                                 X509 *x, size_t chainidx, int *al);
 267 #endif
 268 EXT_RETURN tls_construct_stoc_etm(SSL *s, WPACKET *pkt, unsigned int context,
 269                                   X509 *x, size_t chainidx, int *al);
 270 EXT_RETURN tls_construct_stoc_ems(SSL *s, WPACKET *pkt, unsigned int context,
 271                                   X509 *x, size_t chainidx, int *al);
 272 EXT_RETURN tls_construct_stoc_key_share(SSL *s, WPACKET *pkt,
 273                                         unsigned int context, X509 *x,
 274                                         size_t chainidx, int *al);
 275 /*
 276  * Not in public headers as this is not an official extension. Only used when
 277  * SSL_OP_CRYPTOPRO_TLSEXT_BUG is set.
 278  */
 279 #define TLSEXT_TYPE_cryptopro_bug      0xfde8
 280 EXT_RETURN tls_construct_stoc_cryptopro_bug(SSL *s, WPACKET *pkt,
 281                                             unsigned int context, X509 *x,
 282                                             size_t chainidx, int *al);
 283 EXT_RETURN tls_construct_stoc_psk(SSL *s, WPACKET *pkt, unsigned int context,
 284                                   X509 *x, size_t chainidx, int *al);
 285
 286 /* Client Extension processing */
 287 EXT_RETURN tls_construct_ctos_renegotiate(SSL *s, WPACKET *pkt, unsigned int context,
 288                                    X509 *x, size_t chainidx, int *al);
 289 EXT_RETURN tls_construct_ctos_server_name(SSL *s, WPACKET *pkt, unsigned int context,
 290                                    X509 *x, size_t chainidx, int *al);
 291 #ifndef OPENSSL_NO_SRP
 292 EXT_RETURN tls_construct_ctos_srp(SSL *s, WPACKET *pkt, unsigned int context, X509 *x,
 293                            size_t chainidx, int *al);
 294 #endif
 295 #ifndef OPENSSL_NO_EC
 296 EXT_RETURN tls_construct_ctos_ec_pt_formats(SSL *s, WPACKET *pkt,
 297                                             unsigned int context, X509 *x,
 298                                             size_t chainidx, int *al);
 299 EXT_RETURN tls_construct_ctos_supported_groups(SSL *s, WPACKET *pkt,
 300                                                unsigned int context, X509 *x,
 301                                                size_t chainidx, int *al);
 302 #endif
 303 EXT_RETURN tls_construct_ctos_early_data(SSL *s, WPACKET *pkt,
 304                                          unsigned int context, X509 *x,
 305                                          size_t chainidx, int *al);
 306 EXT_RETURN tls_construct_ctos_session_ticket(SSL *s, WPACKET *pkt,
 307                                              unsigned int context, X509 *x,
 308                                              size_t chainidx, int *al);
 309 EXT_RETURN tls_construct_ctos_sig_algs(SSL *s, WPACKET *pkt,
 310                                        unsigned int context, X509 *x,
 311                                        size_t chainidx, int *al);
 312 #ifndef OPENSSL_NO_OCSP
 313 EXT_RETURN tls_construct_ctos_status_request(SSL *s, WPACKET *pkt,
 314                                              unsigned int context, X509 *x,
 315                                              size_t chainidx, int *al);
 316 #endif
 317 #ifndef OPENSSL_NO_NEXTPROTONEG
 318 EXT_RETURN tls_construct_ctos_npn(SSL *s, WPACKET *pkt, unsigned int context,
 319                                   X509 *x, size_t chainidx, int *al);
 320 #endif
 321 EXT_RETURN tls_construct_ctos_alpn(SSL *s, WPACKET *pkt, unsigned int context,
 322                                    X509 *x, size_t chainidx, int *al);
 323 #ifndef OPENSSL_NO_SRTP
 324 EXT_RETURN tls_construct_ctos_use_srtp(SSL *s, WPACKET *pkt, unsigned int context,
 325                                        X509 *x, size_t chainidx, int *al);
 326 #endif
 327 EXT_RETURN tls_construct_ctos_etm(SSL *s, WPACKET *pkt, unsigned int context,
 328                                   X509 *x, size_t chainidx, int *al);
 329 #ifndef OPENSSL_NO_CT
 330 EXT_RETURN tls_construct_ctos_sct(SSL *s, WPACKET *pkt, unsigned int context,
 331                                   X509 *x, size_t chainidx, int *al);
 332 #endif
 333 EXT_RETURN tls_construct_ctos_ems(SSL *s, WPACKET *pkt, unsigned int context,
 334                                   X509 *x, size_t chainidx, int *al);
 335 EXT_RETURN tls_construct_ctos_supported_versions(SSL *s, WPACKET *pkt,
 336                                                  unsigned int context, X509 *x,
 337                                                  size_t chainidx, int *al);
 338 EXT_RETURN tls_construct_ctos_key_share(SSL *s, WPACKET *pkt,
 339                                         unsigned int context, X509 *x,
 340                                         size_t chainidx, int *al);
 341 EXT_RETURN tls_construct_ctos_psk_kex_modes(SSL *s, WPACKET *pkt,
 342                                             unsigned int context, X509 *x,
 343                                             size_t chainidx, int *al);
 344 EXT_RETURN tls_construct_ctos_cookie(SSL *s, WPACKET *pkt, unsigned int context,
 345                                      X509 *x, size_t chainidx, int *al);
 346 EXT_RETURN tls_construct_ctos_padding(SSL *s, WPACKET *pkt,
 347                                       unsigned int context, X509 *x,
 348                                       size_t chainidx, int *al);
 349 EXT_RETURN tls_construct_ctos_psk(SSL *s, WPACKET *pkt, unsigned int context,
 350                                   X509 *x, size_t chainidx, int *al);
 351 int tls_parse_stoc_renegotiate(SSL *s, PACKET *pkt, unsigned int context,
 352                                X509 *x, size_t chainidx, int *al);
 353 int tls_parse_stoc_server_name(SSL *s, PACKET *pkt, unsigned int context,
 354                                X509 *x, size_t chainidx, int *al);
 355 int tls_parse_stoc_early_data(SSL *s, PACKET *pkt, unsigned int context,
 356                               X509 *x, size_t chainidx, int *al);
 357 #ifndef OPENSSL_NO_EC
 358 int tls_parse_stoc_ec_pt_formats(SSL *s, PACKET *pkt, unsigned int context,
 359                                  X509 *x, size_t chainidx, int *al);
 360 #endif
 361 int tls_parse_stoc_session_ticket(SSL *s, PACKET *pkt, unsigned int context,
 362                                   X509 *x, size_t chainidx, int *al);
 363 #ifndef OPENSSL_NO_OCSP
 364 int tls_parse_stoc_status_request(SSL *s, PACKET *pkt, unsigned int context,
 365                                   X509 *x, size_t chainidx, int *al);
 366 #endif
 367 #ifndef OPENSSL_NO_CT
 368 int tls_parse_stoc_sct(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 369                        size_t chainidx, int *al);
 370 #endif
 371 #ifndef OPENSSL_NO_NEXTPROTONEG
 372 int tls_parse_stoc_npn(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 373                        size_t chainidx, int *al);
 374 #endif
 375 int tls_parse_stoc_alpn(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 376                         size_t chainidx, int *al);
 377 #ifndef OPENSSL_NO_SRTP
 378 int tls_parse_stoc_use_srtp(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 379                             size_t chainidx, int *al);
 380 #endif
 381 int tls_parse_stoc_etm(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 382                        size_t chainidx, int *al);
 383 int tls_parse_stoc_ems(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 384                        size_t chainidx, int *al);
 385 int tls_parse_stoc_key_share(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 386                              size_t chainidx, int *al);
 387 int tls_parse_stoc_cookie(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 388                        size_t chainidx, int *al);
 389 int tls_parse_stoc_psk(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
 390                        size_t chainidx, int *al);