lib/gnutls_int.h

   1 /*
   2  * Copyright (C) 2000-2012 Free Software Foundation, Inc.
   3  *
   4  * Author: Nikos Mavrogiannopoulos
   5  *
   6  * This file is part of GnuTLS.
   7  *
   8  * The GnuTLS is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public License
  10  * as published by the Free Software Foundation; either version 3 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program.  If not, see <http://www.gnu.org/licenses/>
  20  *
  21  */
  22
  23 #ifndef GNUTLS_INT_H
  24 #define GNUTLS_INT_H
  25
  26 #ifdef HAVE_CONFIG_H
  27 #include <config.h>
  28 #endif
  29
  30 #include <stddef.h>
  31 #include <string.h>
  32 #include <stdlib.h>
  33 #include <stdio.h>
  34 #include <ctype.h>
  35 #include <limits.h>
  36 #include <stdint.h>
  37
  38 #ifdef NO_SSIZE_T
  39 #define HAVE_SSIZE_T
  40 typedef int ssize_t;
  41 #endif
  42
  43 #include <sys/types.h>
  44 #include <unistd.h>
  45 #include <sys/stat.h>
  46 #if HAVE_SYS_SOCKET_H
  47 # include <sys/socket.h>
  48 #elif HAVE_WS2TCPIP_H
  49 # include <ws2tcpip.h>
  50 #endif
  51 #include <time.h>
  52 #include <u64.h> /* gnulib for uint64_t */
  53
  54 #ifdef HAVE_LIBNETTLE
  55 # include <nettle/memxor.h>
  56 #else
  57 # include <gl/memxor.h>
  58 # define memxor gl_memxor
  59 #endif
  60
  61 #ifdef __GNUC__
  62 # ifndef _GNUTLS_GCC_VERSION
  63 #  define _GNUTLS_GCC_VERSION (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__)
  64 # endif
  65 # if _GNUTLS_GCC_VERSION >= 30100
  66 #  define likely(x)      __builtin_expect((x), 1)
  67 #  define unlikely(x)    __builtin_expect((x), 0)
  68 # endif
  69 #endif
  70
  71 #ifndef likely
  72 # define likely
  73 # define unlikely
  74 #endif
  75
  76 /* some systems had problems with long long int, thus,
  77  * it is not used.
  78  */
  79 typedef struct
  80 {
  81   unsigned char i[8];
  82 } uint64;
  83
  84 #include <gnutls/gnutls.h>
  85 #include <gnutls/dtls.h>
  86 #include <gnutls/abstract.h>
  87 #include <system.h>
  88
  89 /*
  90  * They are not needed any more. You can simply enable
  91  * the gnutls_log callback to get error descriptions.
  92
  93 #define BUFFERS_DEBUG
  94 #define WRITE_DEBUG
  95 #define READ_DEBUG
  96 #define HANDSHAKE_DEBUG // Prints some information on handshake
  97 #define COMPRESSION_DEBUG
  98 #define DEBUG
  99 */
 100
 101 /* The size of a handshake message should not
 102  * be larger than this value.
 103  */
 104 #define MAX_HANDSHAKE_PACKET_SIZE 48*1024
 105
 106 #define TLS_MAX_SESSION_ID_SIZE 32
 107
 108 /* The maximum digest size of hash algorithms.
 109  */
 110 #define MAX_HASH_SIZE 64
 111 #define MAX_CIPHER_BLOCK_SIZE 16
 112 #define MAX_CIPHER_KEY_SIZE 32
 113
 114 #define MAX_USERNAME_SIZE 128
 115 #define MAX_SERVER_NAME_SIZE 128
 116
 117 #define SESSION_TICKET_KEY_NAME_SIZE 16
 118 #define SESSION_TICKET_KEY_SIZE 16
 119 #define SESSION_TICKET_IV_SIZE 16
 120 #define SESSION_TICKET_MAC_SECRET_SIZE 32
 121
 122 #define AEAD_EXPLICIT_DATA_SIZE 8
 123 #define AEAD_IMPLICIT_DATA_SIZE 4
 124
 125 #define GNUTLS_MASTER_SIZE 48
 126 #define GNUTLS_RANDOM_SIZE 32
 127
 128 /* DTLS */
 129 #define DTLS_RECORD_WINDOW_SIZE 64
 130
 131 /* TLS Extensions */
 132 /* we can receive up to MAX_EXT_TYPES extensions.
 133  */
 134 #define MAX_EXT_TYPES 32
 135
 136   /**
 137    * gnutls_ext_parse_type_t:
 138    * @GNUTLS_EXT_NONE: Never parsed
 139    * @GNUTLS_EXT_ANY: Any extension type.
 140    * @GNUTLS_EXT_APPLICATION: Application extension.
 141    * @GNUTLS_EXT_TLS: TLS-internal extension.
 142    * @GNUTLS_EXT_MANDATORY: Extension parsed even if resuming (or extensions are disabled).
 143    *
 144    * Enumeration of different TLS extension types.  This flag
 145    * indicates for an extension whether it is useful to application
 146    * level or TLS level only.  This is (only) used to parse the
 147    * application level extensions before the "client_hello" callback
 148    * is called.
 149    */
 150   typedef enum
 151   {
 152     GNUTLS_EXT_ANY = 0,
 153     GNUTLS_EXT_APPLICATION = 1,
 154     GNUTLS_EXT_TLS = 2,
 155     GNUTLS_EXT_MANDATORY = 3,
 156     GNUTLS_EXT_NONE = 4
 157   } gnutls_ext_parse_type_t;
 158
 159
 160 /* expire time for resuming sessions */
 161 #define DEFAULT_EXPIRE_TIME 3600
 162
 163 typedef enum transport_t
 164 {
 165   GNUTLS_STREAM,
 166   GNUTLS_DGRAM
 167 } transport_t;
 168
 169 /* the maximum size of encrypted packets */
 170 #define IS_DTLS(session) (session->internals.transport == GNUTLS_DGRAM)
 171
 172 #define DEFAULT_MAX_RECORD_SIZE 16384
 173 #define TLS_RECORD_HEADER_SIZE 5
 174 #define DTLS_RECORD_HEADER_SIZE (TLS_RECORD_HEADER_SIZE+8)
 175 #define RECORD_HEADER_SIZE(session) (IS_DTLS(session) ? DTLS_RECORD_HEADER_SIZE : TLS_RECORD_HEADER_SIZE)
 176 #define MAX_RECORD_HEADER_SIZE DTLS_RECORD_HEADER_SIZE
 177
 178 #define MAX_RECORD_SEND_SIZE(session) (IS_DTLS(session)?((size_t)gnutls_dtls_get_data_mtu(session)):(size_t)session->security_parameters.max_record_send_size)
 179 #define MAX_RECORD_RECV_SIZE(session) ((size_t)session->security_parameters.max_record_recv_size)
 180 #define MAX_PAD_SIZE 255
 181 #define EXTRA_COMP_SIZE 2048
 182 #define MAX_RECORD_OVERHEAD (MAX_CIPHER_BLOCK_SIZE/*iv*/+MAX_PAD_SIZE+EXTRA_COMP_SIZE+MAX_HASH_SIZE/*MAC*/)
 183 #define MAX_RECV_SIZE(session) (MAX_RECORD_OVERHEAD+MAX_RECORD_RECV_SIZE(session)+RECORD_HEADER_SIZE(session))
 184
 185 #define TLS_HANDSHAKE_HEADER_SIZE 4
 186 #define DTLS_HANDSHAKE_HEADER_SIZE (TLS_HANDSHAKE_HEADER_SIZE+8)
 187 #define HANDSHAKE_HEADER_SIZE(session) (IS_DTLS(session) ? DTLS_HANDSHAKE_HEADER_SIZE : TLS_HANDSHAKE_HEADER_SIZE)
 188 #define MAX_HANDSHAKE_HEADER_SIZE DTLS_HANDSHAKE_HEADER_SIZE
 189
 190 /* This is the maximum handshake message size we send without
 191    fragmentation. This currently ignores record layer overhead. */
 192 #define DTLS_DEFAULT_MTU 1200
 193
 194 /* the maximum size of the DTLS cookie */
 195 #define DTLS_MAX_COOKIE_SIZE 32
 196
 197 /* The maximum number of HELLO_VERIFY_REQUEST messages the client
 198    processes before aborting. */
 199 #define MAX_HANDSHAKE_HELLO_VERIFY_REQUESTS 5
 200
 201 /* defaults for verification functions
 202  */
 203 #define DEFAULT_MAX_VERIFY_DEPTH 16
 204 #define DEFAULT_MAX_VERIFY_BITS 16*1024
 205
 206 #include <gnutls_mem.h>
 207
 208 #define MEMSUB(x,y) ((ssize_t)((ptrdiff_t)x-(ptrdiff_t)y))
 209
 210 #define DECR_LEN(len, x) do { len-=x; if (len<0) {gnutls_assert(); return GNUTLS_E_UNEXPECTED_PACKET_LENGTH;} } while (0)
 211 #define DECR_LENGTH_RET(len, x, RET) do { len-=x; if (len<0) {gnutls_assert(); return RET;} } while (0)
 212 #define DECR_LENGTH_COM(len, x, COM) do { len-=x; if (len<0) {gnutls_assert(); COM;} } while (0)
 213
 214 #define GNUTLS_POINTER_TO_INT(_) ((int) GNUTLS_POINTER_TO_INT_CAST (_))
 215 #define GNUTLS_INT_TO_POINTER(_) ((void*) GNUTLS_POINTER_TO_INT_CAST (_))
 216
 217 typedef struct
 218 {
 219   uint8_t pint[3];
 220 } uint24;
 221
 222 #include <gnutls_mpi.h>
 223
 224 typedef enum handshake_state_t
 225 { STATE0 = 0, STATE1, STATE2,
 226   STATE3, STATE4, STATE5, STATE6, STATE7, STATE8,
 227   STATE9, STATE10, STATE11, STATE12, STATE13, STATE14,
 228   STATE15, STATE16, STATE17,
 229   STATE20 = 20, STATE21, STATE22,
 230   STATE30 = 30, STATE31, STATE40 = 40, STATE41, STATE50 = 50,
 231   STATE60 = 60, STATE61, STATE62, STATE70, STATE71
 232 } handshake_state_t;
 233
 234 typedef enum heartbeat_state_t
 235 {
 236   SHB_SEND1 = 0,
 237   SHB_SEND2,
 238   SHB_RECV,
 239 } heartbeat_state_t;
 240
 241 typedef enum recv_state_t
 242 {
 243   RECV_STATE_0 = 0,
 244   RECV_STATE_DTLS_RETRANSMIT,
 245 } recv_state_t;
 246
 247 #include <gnutls_str.h>
 248
 249 /* This is the maximum number of algorithms (ciphers or macs etc).
 250  * keep it synced with GNUTLS_MAX_ALGORITHM_NUM in gnutls.h
 251  */
 252 #define MAX_ALGOS GNUTLS_MAX_ALGORITHM_NUM
 253
 254 typedef enum extensions_t
 255 {
 256   GNUTLS_EXTENSION_SERVER_NAME = 0,
 257   GNUTLS_EXTENSION_MAX_RECORD_SIZE = 1,
 258   GNUTLS_EXTENSION_STATUS_REQUEST = 5,
 259   GNUTLS_EXTENSION_CERT_TYPE = 9,
 260   GNUTLS_EXTENSION_SUPPORTED_ECC = 10,
 261   GNUTLS_EXTENSION_SUPPORTED_ECC_PF = 11,
 262   GNUTLS_EXTENSION_SRP = 12,
 263   GNUTLS_EXTENSION_SIGNATURE_ALGORITHMS = 13,
 264   GNUTLS_EXTENSION_SRTP = 14,
 265   GNUTLS_EXTENSION_HEARTBEAT = 15,
 266   GNUTLS_EXTENSION_SESSION_TICKET = 35,
 267   GNUTLS_EXTENSION_SAFE_RENEGOTIATION = 65281   /* aka: 0xff01 */
 268 } extensions_t;
 269
 270 typedef enum
 271 { CIPHER_STREAM, CIPHER_BLOCK } cipher_type_t;
 272
 273 #define RESUME_TRUE 1
 274 #define RESUME_FALSE 0
 275
 276 /* Record Protocol */
 277 typedef enum content_type_t
 278 {
 279   GNUTLS_CHANGE_CIPHER_SPEC = 20, GNUTLS_ALERT,
 280   GNUTLS_HANDSHAKE, GNUTLS_APPLICATION_DATA,
 281   GNUTLS_HEARTBEAT
 282 } content_type_t;
 283
 284
 285 #define GNUTLS_PK_ANY (gnutls_pk_algorithm_t)-1
 286 #define GNUTLS_PK_NONE (gnutls_pk_algorithm_t)-2
 287
 288 /* Message buffers (mbuffers) structures */
 289
 290 /* this is actually the maximum number of distinct handshake
 291  * messages that can arrive in a single flight
 292  */
 293 #define MAX_HANDSHAKE_MSGS 6
 294 typedef struct
 295 {
 296   /* Handshake layer type and sequence of message */
 297   gnutls_handshake_description_t htype;
 298   uint32_t length;
 299
 300   /* valid in DTLS */
 301   uint16_t sequence;
 302
 303   /* indicate whether that message is complete.
 304    * complete means start_offset == 0 and end_offset == length
 305    */
 306   uint32_t start_offset;
 307   uint32_t end_offset;
 308
 309   uint8_t header[MAX_HANDSHAKE_HEADER_SIZE];
 310   int header_size;
 311
 312   gnutls_buffer_st data;
 313 } handshake_buffer_st;
 314
 315 typedef struct mbuffer_st
 316 {
 317   /* when used in mbuffer_head_st */
 318   struct mbuffer_st *next;
 319   struct mbuffer_st *prev;
 320
 321   /* msg->size - mark = number of bytes left to process in this
 322      message. Mark should only be non-zero when this buffer is the
 323      head of the queue. */
 324   size_t mark;
 325
 326
 327   /* the data */
 328   gnutls_datum_t msg;
 329   size_t maximum_size;
 330
 331   /* used during fill in, to separate header from data
 332    * body. */
 333   unsigned int user_mark;
 334
 335   /* Filled in by record layer on recv:
 336    * type, record_sequence
 337    */
 338
 339   /* record layer content type */
 340   content_type_t type;
 341
 342   /* record layer sequence */
 343   uint64 record_sequence;
 344
 345   /* Filled in by handshake layer on send:
 346    * type, epoch, htype, handshake_sequence
 347    */
 348
 349   /* Record layer epoch of message */
 350   uint16_t epoch;
 351
 352   /* Handshake layer type and sequence of message */
 353   gnutls_handshake_description_t htype;
 354   uint16_t handshake_sequence;
 355 } mbuffer_st;
 356
 357 typedef struct mbuffer_head_st
 358 {
 359   mbuffer_st *head;
 360   mbuffer_st *tail;
 361
 362   unsigned int length;
 363   size_t byte_length;
 364 } mbuffer_head_st;
 365
 366 /* Store & Retrieve functions defines:
 367  */
 368
 369 typedef struct auth_cred_st
 370 {
 371   gnutls_credentials_type_t algorithm;
 372
 373   /* the type of credentials depends on algorithm
 374    */
 375   void *credentials;
 376   struct auth_cred_st *next;
 377 } auth_cred_st;
 378
 379 struct gnutls_key_st
 380 {
 381   /* For ECDH KX */
 382   gnutls_pk_params_st ecdh_params;
 383   bigint_t ecdh_x;
 384   bigint_t ecdh_y;
 385
 386   /* For DH KX */
 387   gnutls_datum_t key;
 388   bigint_t KEY;
 389   bigint_t client_Y;
 390   bigint_t client_g;
 391   bigint_t client_p;
 392   bigint_t dh_secret;
 393   /* for SRP */
 394   bigint_t A;
 395   bigint_t B;
 396   bigint_t u;
 397   bigint_t b;
 398   bigint_t a;
 399   bigint_t x;
 400   /* RSA: e, m
 401    */
 402   bigint_t rsa[2];
 403
 404   /* this is used to hold the peers authentication data
 405    */
 406   /* auth_info_t structures SHOULD NOT contain malloced
 407    * elements. Check gnutls_session_pack.c, and gnutls_auth.c.
 408    * Remember that this should be calloced!
 409    */
 410   void *auth_info;
 411   gnutls_credentials_type_t auth_info_type;
 412   int auth_info_size;           /* needed in order to store to db for restoring
 413                                  */
 414   uint8_t crypt_algo;
 415
 416   auth_cred_st *cred;           /* used to specify keys/certificates etc */
 417
 418   int crt_requested;
 419   /* some ciphersuites use this
 420    * to provide client authentication.
 421    * 1 if client auth was requested
 422    * by the peer, 0 otherwise
 423    *** In case of a server this
 424    * holds 1 if we should wait
 425    * for a client certificate verify
 426    */
 427 };
 428 typedef struct gnutls_key_st gnutls_key_st;
 429
 430 struct pin_info_st
 431 {
 432   gnutls_pin_callback_t cb;
 433   void* data;
 434 };
 435
 436 struct record_state_st;
 437 typedef struct record_state_st record_state_st;
 438
 439 struct record_parameters_st;
 440 typedef struct record_parameters_st record_parameters_st;
 441
 442 /* STATE (cont) */
 443
 444 #include <gnutls_hash_int.h>
 445 #include <gnutls_cipher_int.h>
 446 #include <gnutls_compress.h>
 447
 448 typedef struct
 449 {
 450   uint8_t hash_algorithm;
 451   uint8_t sign_algorithm;       /* pk algorithm actually */
 452 } sign_algorithm_st;
 453
 454 /* This structure holds parameters got from TLS extension
 455  * mechanism. (some extensions may hold parameters in auth_info_t
 456  * structures also - see SRP).
 457  */
 458
 459 #define MAX_SIGNATURE_ALGORITHMS 16
 460 #define MAX_SIGN_ALGO_SIZE (2 + MAX_SIGNATURE_ALGORITHMS * 2)
 461
 462 #define MAX_VERIFY_DATA_SIZE 36 /* in SSL 3.0, 12 in TLS 1.0 */
 463
 464 /* auth_info_t structures now MAY contain malloced
 465  * elements.
 466  */
 467
 468 /* This structure and auth_info_t, are stored in the resume database,
 469  * and are restored, in case of resume.
 470  * Holds all the required parameters to resume the current
 471  * session.
 472  */
 473
 474 /* if you add anything in Security_Parameters struct, then
 475  * also modify CPY_COMMON in gnutls_constate.c.
 476  */
 477
 478 /* Note that the security parameters structure is set up after the
 479  * handshake has finished. The only value you may depend on while
 480  * the handshake is in progress is the cipher suite value.
 481  */
 482 typedef struct
 483 {
 484   unsigned int entity; /* GNUTLS_SERVER or GNUTLS_CLIENT */
 485   gnutls_kx_algorithm_t kx_algorithm;
 486
 487   /* The epoch used to read and write */
 488   uint16_t epoch_read;
 489   uint16_t epoch_write;
 490
 491   /* The epoch that the next handshake will initialize. */
 492   uint16_t epoch_next;
 493
 494   /* The epoch at index 0 of record_parameters. */
 495   uint16_t epoch_min;
 496
 497   /* this is the ciphersuite we are going to use
 498    * moved here from internals in order to be restored
 499    * on resume;
 500    */
 501   uint8_t cipher_suite[2];
 502   gnutls_compression_method_t compression_method;
 503   uint8_t master_secret[GNUTLS_MASTER_SIZE];
 504   uint8_t client_random[GNUTLS_RANDOM_SIZE];
 505   uint8_t server_random[GNUTLS_RANDOM_SIZE];
 506   uint8_t session_id[TLS_MAX_SESSION_ID_SIZE];
 507   uint8_t session_id_size;
 508   time_t timestamp;
 509
 510   /* The send size is the one requested by the programmer.
 511    * The recv size is the one negotiated with the peer.
 512    */
 513   uint16_t max_record_send_size;
 514   uint16_t max_record_recv_size;
 515   /* holds the negotiated certificate type */
 516   gnutls_certificate_type_t cert_type;
 517   gnutls_ecc_curve_t ecc_curve; /* holds the first supported ECC curve requested by client */
 518   gnutls_protocol_t version;    /* moved here */
 519
 520   /* Holds the signature algorithm used in this session - If any */
 521   gnutls_sign_algorithm_t sign_algo;
 522
 523   /* FIXME: The following are not saved in the session storage
 524    * for session resumption.
 525    */
 526
 527   /* Used by extensions that enable supplemental data: Which ones
 528    * do that? Do they belong in security parameters?
 529    */
 530   int do_recv_supplemental, do_send_supplemental;
 531 } security_parameters_st;
 532
 533 struct record_state_st
 534 {
 535   gnutls_datum_t mac_secret;
 536   gnutls_datum_t IV;
 537   gnutls_datum_t key;
 538   auth_cipher_hd_st cipher_state;
 539   comp_hd_st compression_state;
 540   uint64 sequence_number;
 541 };
 542
 543 /* These are used to resolve relative epochs. These values are just
 544    outside the 16 bit range to prevent off-by-one errors. An absolute
 545    epoch may be referred to by its numeric id in the range
 546    0x0000-0xffff. */
 547 #define EPOCH_READ_CURRENT  70000
 548 #define EPOCH_WRITE_CURRENT 70001
 549 #define EPOCH_NEXT          70002
 550
 551 struct record_parameters_st
 552 {
 553   uint16_t epoch;
 554   int initialized;
 555
 556   gnutls_cipher_algorithm_t cipher_algorithm;
 557   gnutls_mac_algorithm_t mac_algorithm;
 558   gnutls_compression_method_t compression_algorithm;
 559
 560   /* for DTLS */
 561   uint64_t record_sw[DTLS_RECORD_WINDOW_SIZE];
 562   unsigned int record_sw_size;
 563
 564   record_state_st read;
 565   record_state_st write;
 566
 567   /* Whether this state is in use, i.e., if there is
 568      a pending handshake message waiting to be encrypted
 569      under this epoch's parameters.
 570    */
 571   int usage_cnt;
 572 };
 573
 574 typedef struct
 575 {
 576   unsigned int priority[MAX_ALGOS];
 577   unsigned int algorithms;
 578 } priority_st;
 579
 580 typedef enum
 581 {
 582   SR_DISABLED,
 583   SR_UNSAFE,
 584   SR_PARTIAL,
 585   SR_SAFE
 586 } safe_renegotiation_t;
 587
 588 /* For the external api */
 589 struct gnutls_priority_st
 590 {
 591   priority_st cipher;
 592   priority_st mac;
 593   priority_st kx;
 594   priority_st compression;
 595   priority_st protocol;
 596   priority_st cert_type;
 597   priority_st sign_algo;
 598   priority_st supported_ecc;
 599
 600   /* to disable record padding */
 601   unsigned int no_extensions:1;
 602   unsigned int no_padding:1;
 603   unsigned int allow_large_records:1;
 604   safe_renegotiation_t sr;
 605   unsigned int ssl3_record_version:1;
 606   unsigned int server_precedence:1;
 607   unsigned int allow_key_usage_violation:1;
 608   unsigned int allow_weak_keys:1;
 609   /* Whether stateless compression will be used */
 610   unsigned int stateless_compression:1;
 611   unsigned int additional_verify_flags;
 612 };
 613
 614 #define ENABLE_COMPAT(x) \
 615               (x)->no_padding = 1; \
 616               (x)->allow_large_records = 1; \
 617               (x)->allow_key_usage_violation = 1; \
 618               (x)->allow_weak_keys = 1
 619
 620 /* DH and RSA parameters types.
 621  */
 622 typedef struct gnutls_dh_params_int
 623 {
 624   /* [0] is the prime, [1] is the generator.
 625    */
 626   bigint_t params[2];
 627   int q_bits; /* length of q in bits. If zero then length is unknown.
 628               */
 629 } dh_params_st;
 630
 631 typedef struct
 632 {
 633   gnutls_dh_params_t dh_params;
 634   int free_dh_params;
 635   gnutls_rsa_params_t rsa_params;
 636   int free_rsa_params;
 637 } internal_params_st;
 638
 639 /* DTLS session state
 640  */
 641 typedef struct
 642 {
 643   /* HelloVerifyRequest DOS prevention cookie */
 644   uint8_t  cookie[DTLS_MAX_COOKIE_SIZE];
 645   uint8_t cookie_len;
 646
 647   /* For DTLS handshake fragmentation and reassembly. */
 648   uint16_t hsk_write_seq;
 649   /* the sequence number of the expected packet */
 650   unsigned int hsk_read_seq;
 651   uint16_t mtu;
 652
 653   /* a flight transmission is in process */
 654   unsigned int flight_init:1;
 655   /* whether this is the last flight in the protocol  */
 656   unsigned int last_flight:1;
 657
 658   /* the retransmission timeout in milliseconds */
 659   unsigned int retrans_timeout_ms;
 660   /* the connection timeout in milliseconds */
 661   unsigned int total_timeout_ms;
 662
 663   unsigned int hsk_hello_verify_requests;
 664
 665   /* non blocking stuff variables */
 666   unsigned int blocking:1;
 667   /* starting time of current handshake */
 668   struct timespec handshake_start_time;
 669
 670   /* The actual retrans_timeout for the next message (e.g. doubled or so)
 671    */
 672   unsigned int actual_retrans_timeout_ms;
 673
 674   /* timers to handle async handshake after gnutls_handshake()
 675    * has terminated. Required to handle retransmissions.
 676    */
 677   time_t async_term;
 678
 679   /* last retransmission triggered by record layer */
 680   struct timespec last_retransmit;
 681   unsigned int packets_dropped;
 682 } dtls_st;
 683
 684
 685 typedef union
 686 {
 687   void *ptr;
 688   uint32_t num;
 689 } extension_priv_data_t;
 690
 691 typedef struct
 692 {
 693   /* holds all the parsed data received by the record layer */
 694   mbuffer_head_st record_buffer;
 695
 696   int handshake_hash_buffer_prev_len;           /* keeps the length of handshake_hash_buffer, excluding
 697                                                  * the last received message */
 698   gnutls_buffer_st handshake_hash_buffer;       /* used to keep the last received handshake
 699                                                  * message */
 700   unsigned int resumable:1;              /* TRUE or FALSE - if we can resume that session */
 701   unsigned int ticket_sent:1;            /* whether a session ticket was sent */
 702   handshake_state_t handshake_final_state;
 703   handshake_state_t handshake_state;    /* holds
 704                                          * a number which indicates where
 705                                          * the handshake procedure has been
 706                                          * interrupted. If it is 0 then
 707                                          * no interruption has happened.
 708                                          */
 709
 710   int invalid_connection:1;     /* true or FALSE - if this session is valid */
 711
 712   int may_not_read:1;           /* if it's 0 then we can read/write, otherwise it's forbiden to read/write
 713                                  */
 714   int may_not_write:1;
 715   int read_eof:1;               /* non-zero if we have received a closure alert. */
 716
 717   int last_alert;               /* last alert received */
 718
 719   /* The last handshake messages sent or received.
 720    */
 721   int last_handshake_in;
 722   int last_handshake_out;
 723
 724   /* priorities */
 725   struct gnutls_priority_st priorities;
 726
 727   /* resumed session */
 728   unsigned int resumed:1;  /* RESUME_TRUE or FALSE - if we are resuming a session */
 729   unsigned int resumption_requested:1; /* non-zero if resumption was requested by client */
 730   security_parameters_st resumed_security_parameters;
 731
 732   /* These buffers are used in the handshake
 733    * protocol only. freed using _gnutls_handshake_io_buffer_clear();
 734    */
 735   mbuffer_head_st handshake_send_buffer;
 736   handshake_buffer_st handshake_recv_buffer[MAX_HANDSHAKE_MSGS];
 737   int handshake_recv_buffer_size;
 738
 739   /* this buffer holds a record packet -mostly used for
 740    * non blocking IO.
 741    */
 742   mbuffer_head_st record_recv_buffer;   /* buffer holding the unparsed record that is currently
 743                                          * being received */
 744   mbuffer_head_st record_send_buffer;   /* holds cached data
 745                                          * for the gnutls_io_write_buffered()
 746                                          * function.
 747                                          */
 748   size_t record_send_buffer_user_size;  /* holds the
 749                                          * size of the user specified data to
 750                                          * send.
 751                                          */
 752
 753   int expire_time;              /* after expire_time seconds this session will expire */
 754   struct mod_auth_st_int *auth_struct;  /* used in handshake packets and KX algorithms */
 755
 756   /* this is the highest version available
 757    * to the peer. (advertized version).
 758    * This is obtained by the Handshake Client Hello
 759    * message. (some implementations read the Record version)
 760    */
 761   uint8_t adv_version_major;
 762   uint8_t adv_version_minor;
 763
 764   /* if this is non zero a certificate request message
 765    * will be sent to the client. - only if the ciphersuite
 766    * supports it.
 767    */
 768   int send_cert_req;
 769
 770   /* bits to use for DHE and DHA
 771    * use _gnutls_dh_get_prime_bits() and gnutls_dh_set_prime_bits()
 772    * to access it.
 773    */
 774   uint16_t dh_prime_bits;
 775
 776   size_t max_handshake_data_buffer_size;
 777
 778   /* PUSH & PULL functions.
 779    */
 780   gnutls_pull_timeout_func pull_timeout_func;
 781   gnutls_pull_func pull_func;
 782   gnutls_push_func push_func;
 783   gnutls_vec_push_func vec_push_func;
 784   gnutls_errno_func errno_func;
 785   /* Holds the first argument of PUSH and PULL
 786    * functions;
 787    */
 788   gnutls_transport_ptr_t transport_recv_ptr;
 789   gnutls_transport_ptr_t transport_send_ptr;
 790
 791   /* STORE & RETRIEVE functions. Only used if other
 792    * backend than gdbm is used.
 793    */
 794   gnutls_db_store_func db_store_func;
 795   gnutls_db_retr_func db_retrieve_func;
 796   gnutls_db_remove_func db_remove_func;
 797   void *db_ptr;
 798
 799   /* post client hello callback (server side only)
 800    */
 801   gnutls_handshake_post_client_hello_func user_hello_func;
 802
 803   /* holds the selected certificate and key.
 804    * use _gnutls_selected_certs_deinit() and _gnutls_selected_certs_set()
 805    * to change them.
 806    */
 807   gnutls_pcert_st *selected_cert_list;
 808   int selected_cert_list_length;
 809   struct gnutls_privkey_st *selected_key;
 810   int selected_need_free:1;
 811
 812   /* holds the extensions we sent to the peer
 813    * (in case of a client)
 814    */
 815   uint16_t extensions_sent[MAX_EXT_TYPES];
 816   uint16_t extensions_sent_size;
 817
 818   /* is 0 if we are to send the whole PGP key, or non zero
 819    * if the fingerprint is to be sent.
 820    */
 821   int pgp_fingerprint;
 822
 823   /* This holds the default version that our first
 824    * record packet will have. */
 825   uint8_t default_record_version[2];
 826
 827   void *user_ptr;
 828
 829   int enable_private;           /* non zero to
 830                                  * enable cipher suites
 831                                  * which have 0xFF status.
 832                                  */
 833
 834   /* Holds 0 if the last called function was interrupted while
 835    * receiving, and non zero otherwise.
 836    */
 837   int direction;
 838
 839   /* This callback will be used (if set) to receive an
 840    * openpgp key. (if the peer sends a fingerprint)
 841    */
 842   gnutls_openpgp_recv_key_func openpgp_recv_key_func;
 843
 844   /* If non zero the server will not advertise the CA's he
 845    * trusts (do not send an RDN sequence).
 846    */
 847   int ignore_rdn_sequence;
 848
 849   /* This is used to set an arbitary version in the RSA
 850    * PMS secret. Can be used by clients to test whether the
 851    * server checks that version. (** only used in gnutls-cli-debug)
 852    */
 853   uint8_t rsa_pms_version[2];
 854
 855   /* Here we cache the DH or RSA parameters got from the
 856    * credentials structure, or from a callback. That is to
 857    * minimize external calls.
 858    */
 859   internal_params_st params;
 860
 861   /* To avoid using global variables, and especially on Windows where
 862    * the application may use a different errno variable than GnuTLS,
 863    * it is possible to use gnutls_transport_set_errno to set a
 864    * session-specific errno variable in the user-replaceable push/pull
 865    * functions.  This value is used by the send/recv functions.  (The
 866    * strange name of this variable is because 'errno' is typically
 867    * #define'd.)
 868    */
 869   int errnum;
 870
 871   /* Function used to perform public-key signing operation during
 872      handshake.  Used by gnutls_sig.c:_gnutls_tls_sign(), see also
 873      gnutls_sign_callback_set(). */
 874   gnutls_sign_func sign_func;
 875   void *sign_func_userdata;
 876
 877   /* minimum bits to allow for SRP
 878    * use gnutls_srp_set_prime_bits() to adjust it.
 879    */
 880   uint16_t srp_prime_bits;
 881
 882   /* A handshake process has been completed */
 883   unsigned int initial_negotiation_completed:1;
 884
 885   struct
 886   {
 887     uint16_t type;
 888     extension_priv_data_t priv;
 889     int set:1;
 890   } extension_int_data[MAX_EXT_TYPES];
 891
 892   struct
 893   {
 894     uint16_t type;
 895     extension_priv_data_t priv;
 896     int set:1;
 897   } resumed_extension_int_data[MAX_EXT_TYPES];
 898   /* The type of transport protocol; stream or datagram */
 899   transport_t transport;
 900
 901   /* DTLS session state */
 902   dtls_st dtls;
 903
 904   /* if set it means that the master key was set using
 905    * gnutls_session_set_master() rather than being negotiated. */
 906   unsigned int premaster_set:1;
 907
 908   unsigned int cb_tls_unique_len;
 909   unsigned char cb_tls_unique[MAX_VERIFY_DATA_SIZE];
 910
 911   time_t handshake_endtime; /* end time in seconds */
 912   unsigned int handshake_timeout_ms; /* timeout in milliseconds */
 913
 914   gnutls_buffer_st hb_local_data;
 915   gnutls_buffer_st hb_remote_data;
 916   struct timespec hb_ping_start; /* timestamp: when first HeartBeat ping was sent*/
 917   struct timespec hb_ping_sent; /* timestamp: when last HeartBeat ping was sent*/
 918   unsigned int hb_actual_retrans_timeout_ms; /* current timeout, in milliseconds*/
 919   unsigned int hb_retrans_timeout_ms; /* the default timeout, in milliseconds*/
 920   unsigned int hb_total_timeout_ms; /* the total timeout, in milliseconds*/
 921
 922   heartbeat_state_t hb_state; /* for ping */
 923
 924   recv_state_t recv_state; /* state of the receive function */
 925
 926   /* If you add anything here, check _gnutls_handshake_internal_state_clear().
 927    */
 928 } internals_st;
 929
 930 /* Maximum number of epochs we keep around. */
 931 #define MAX_EPOCH_INDEX 16
 932
 933 struct gnutls_session_int
 934 {
 935   security_parameters_st security_parameters;
 936   record_parameters_st *record_parameters[MAX_EPOCH_INDEX];
 937   internals_st internals;
 938   gnutls_key_st key;
 939 };
 940
 941
 942 /* functions
 943  */
 944 void _gnutls_free_auth_info (gnutls_session_t session);
 945
 946 /* These two macros return the advertised TLS version of
 947  * the peer.
 948  */
 949 #define _gnutls_get_adv_version_major( session) \
 950         session->internals.adv_version_major
 951
 952 #define _gnutls_get_adv_version_minor( session) \
 953         session->internals.adv_version_minor
 954
 955 #define set_adv_version( session, major, minor) \
 956         session->internals.adv_version_major = major; \
 957         session->internals.adv_version_minor = minor
 958
 959 void _gnutls_set_adv_version (gnutls_session_t, gnutls_protocol_t);
 960 gnutls_protocol_t _gnutls_get_adv_version (gnutls_session_t);
 961
 962 int _gnutls_is_secure_mem_null (const void *);
 963
 964 inline static gnutls_protocol_t
 965 _gnutls_protocol_get_version (gnutls_session_t session)
 966 {
 967   return session->security_parameters.version;
 968 }
 969
 970 #define gnutls_protocol_get_version _gnutls_protocol_get_version
 971
 972 inline static void
 973 _gnutls_set_current_version (gnutls_session_t session,
 974                              gnutls_protocol_t version)
 975 {
 976   session->security_parameters.version = version;
 977 }
 978
 979
 980 #endif /* GNUTLS_INT_H */