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_VERIFY_DEPTH 32
 204 #define DEFAULT_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,
 227   STATE6, STATE7, STATE8, STATE9, STATE11 = 11,
 228   STATE20 = 20, STATE21, STATE22,
 229   STATE30 = 30, STATE31, STATE40 = 40, STATE41, STATE50 = 50,
 230   STATE60 = 60, STATE61, STATE62, STATE70, STATE71
 231 } handshake_state_t;
 232
 233 #include <gnutls_str.h>
 234
 235 /* This is the maximum number of algorithms (ciphers or macs etc).
 236  * keep it synced with GNUTLS_MAX_ALGORITHM_NUM in gnutls.h
 237  */
 238 #define MAX_ALGOS GNUTLS_MAX_ALGORITHM_NUM
 239
 240 typedef enum extensions_t
 241 {
 242   GNUTLS_EXTENSION_SERVER_NAME = 0,
 243   GNUTLS_EXTENSION_MAX_RECORD_SIZE = 1,
 244   GNUTLS_EXTENSION_CERT_TYPE = 9,
 245   GNUTLS_EXTENSION_SUPPORTED_ECC = 10,
 246   GNUTLS_EXTENSION_SUPPORTED_ECC_PF = 11,
 247   GNUTLS_EXTENSION_SRP = 12,
 248   GNUTLS_EXTENSION_SIGNATURE_ALGORITHMS = 13,
 249   GNUTLS_EXTENSION_SESSION_TICKET = 35,
 250   GNUTLS_EXTENSION_SAFE_RENEGOTIATION = 65281   /* aka: 0xff01 */
 251 } extensions_t;
 252
 253 typedef enum
 254 { CIPHER_STREAM, CIPHER_BLOCK } cipher_type_t;
 255
 256 #define RESUME_TRUE 1
 257 #define RESUME_FALSE 0
 258
 259 /* Record Protocol */
 260 typedef enum content_type_t
 261 {
 262   GNUTLS_CHANGE_CIPHER_SPEC = 20, GNUTLS_ALERT,
 263   GNUTLS_HANDSHAKE, GNUTLS_APPLICATION_DATA,
 264 } content_type_t;
 265
 266
 267 #define GNUTLS_PK_ANY (gnutls_pk_algorithm_t)-1
 268 #define GNUTLS_PK_NONE (gnutls_pk_algorithm_t)-2
 269
 270 /* Message buffers (mbuffers) structures */
 271
 272 /* this is actually the maximum number of distinct handshake
 273  * messages that can arrive in a single flight
 274  */
 275 #define MAX_HANDSHAKE_MSGS 6
 276 typedef struct
 277 {
 278   /* Handshake layer type and sequence of message */
 279   gnutls_handshake_description_t htype;
 280   uint32_t length;
 281
 282   /* valid in DTLS */
 283   uint16_t sequence;
 284
 285   /* indicate whether that message is complete.
 286    * complete means start_offset == 0 and end_offset == length
 287    */
 288   uint32_t start_offset;
 289   uint32_t end_offset;
 290
 291   uint8_t header[MAX_HANDSHAKE_HEADER_SIZE];
 292   int header_size;
 293
 294   gnutls_buffer_st data;
 295 } handshake_buffer_st;
 296
 297 typedef struct mbuffer_st
 298 {
 299   /* when used in mbuffer_head_st */
 300   struct mbuffer_st *next;
 301   struct mbuffer_st *prev;
 302
 303   /* msg->size - mark = number of bytes left to process in this
 304      message. Mark should only be non-zero when this buffer is the
 305      head of the queue. */
 306   size_t mark;
 307
 308
 309   /* the data */
 310   gnutls_datum_t msg;
 311   size_t maximum_size;
 312
 313   /* used during fill in, to separate header from data
 314    * body. */
 315   unsigned int user_mark;
 316
 317   /* Filled in by record layer on recv:
 318    * type, record_sequence
 319    */
 320
 321   /* record layer content type */
 322   content_type_t type;
 323
 324   /* record layer sequence */
 325   uint64 record_sequence;
 326
 327   /* Filled in by handshake layer on send:
 328    * type, epoch, htype, handshake_sequence
 329    */
 330
 331   /* Record layer epoch of message */
 332   uint16_t epoch;
 333
 334   /* Handshake layer type and sequence of message */
 335   gnutls_handshake_description_t htype;
 336   uint16_t handshake_sequence;
 337 } mbuffer_st;
 338
 339 typedef struct mbuffer_head_st
 340 {
 341   mbuffer_st *head;
 342   mbuffer_st *tail;
 343
 344   unsigned int length;
 345   size_t byte_length;
 346 } mbuffer_head_st;
 347
 348 /* Store & Retrieve functions defines:
 349  */
 350
 351 typedef struct auth_cred_st
 352 {
 353   gnutls_credentials_type_t algorithm;
 354
 355   /* the type of credentials depends on algorithm
 356    */
 357   void *credentials;
 358   struct auth_cred_st *next;
 359 } auth_cred_st;
 360
 361 struct gnutls_key_st
 362 {
 363   /* For ECDH KX */
 364   gnutls_pk_params_st ecdh_params;
 365   bigint_t ecdh_x;
 366   bigint_t ecdh_y;
 367
 368   /* For DH KX */
 369   gnutls_datum_t key;
 370   bigint_t KEY;
 371   bigint_t client_Y;
 372   bigint_t client_g;
 373   bigint_t client_p;
 374   bigint_t dh_secret;
 375   /* for SRP */
 376   bigint_t A;
 377   bigint_t B;
 378   bigint_t u;
 379   bigint_t b;
 380   bigint_t a;
 381   bigint_t x;
 382   /* RSA: e, m
 383    */
 384   bigint_t rsa[2];
 385
 386   /* this is used to hold the peers authentication data
 387    */
 388   /* auth_info_t structures SHOULD NOT contain malloced
 389    * elements. Check gnutls_session_pack.c, and gnutls_auth.c.
 390    * Remember that this should be calloced!
 391    */
 392   void *auth_info;
 393   gnutls_credentials_type_t auth_info_type;
 394   int auth_info_size;           /* needed in order to store to db for restoring
 395                                  */
 396   uint8_t crypt_algo;
 397
 398   auth_cred_st *cred;           /* used to specify keys/certificates etc */
 399
 400   int crt_requested;
 401   /* some ciphersuites use this
 402    * to provide client authentication.
 403    * 1 if client auth was requested
 404    * by the peer, 0 otherwise
 405    *** In case of a server this
 406    * holds 1 if we should wait
 407    * for a client certificate verify
 408    */
 409 };
 410 typedef struct gnutls_key_st *gnutls_key_st;
 411
 412 struct pin_info_st
 413 {
 414   gnutls_pin_callback_t cb;
 415   void* data;
 416 };
 417
 418 struct record_state_st;
 419 typedef struct record_state_st record_state_st;
 420
 421 struct record_parameters_st;
 422 typedef struct record_parameters_st record_parameters_st;
 423
 424 /* STATE (cont) */
 425
 426 #include <gnutls_hash_int.h>
 427 #include <gnutls_cipher_int.h>
 428 #include <gnutls_compress.h>
 429
 430 typedef struct
 431 {
 432   uint8_t hash_algorithm;
 433   uint8_t sign_algorithm;       /* pk algorithm actually */
 434 } sign_algorithm_st;
 435
 436 /* This structure holds parameters got from TLS extension
 437  * mechanism. (some extensions may hold parameters in auth_info_t
 438  * structures also - see SRP).
 439  */
 440
 441 #define MAX_SIGNATURE_ALGORITHMS 16
 442 #define MAX_SIGN_ALGO_SIZE (2 + MAX_SIGNATURE_ALGORITHMS * 2)
 443
 444 #define MAX_VERIFY_DATA_SIZE 36 /* in SSL 3.0, 12 in TLS 1.0 */
 445
 446 /* auth_info_t structures now MAY contain malloced
 447  * elements.
 448  */
 449
 450 /* This structure and auth_info_t, are stored in the resume database,
 451  * and are restored, in case of resume.
 452  * Holds all the required parameters to resume the current
 453  * session.
 454  */
 455
 456 /* if you add anything in Security_Parameters struct, then
 457  * also modify CPY_COMMON in gnutls_constate.c.
 458  */
 459
 460 /* Note that the security parameters structure is set up after the
 461  * handshake has finished. The only value you may depend on while
 462  * the handshake is in progress is the cipher suite value.
 463  */
 464 typedef struct
 465 {
 466   unsigned int entity; /* GNUTLS_SERVER or GNUTLS_CLIENT */
 467   gnutls_kx_algorithm_t kx_algorithm;
 468
 469   /* The epoch used to read and write */
 470   uint16_t epoch_read;
 471   uint16_t epoch_write;
 472
 473   /* The epoch that the next handshake will initialize. */
 474   uint16_t epoch_next;
 475
 476   /* The epoch at index 0 of record_parameters. */
 477   uint16_t epoch_min;
 478
 479   /* this is the ciphersuite we are going to use
 480    * moved here from internals in order to be restored
 481    * on resume;
 482    */
 483   uint8_t cipher_suite[2];
 484   gnutls_compression_method_t compression_method;
 485   uint8_t master_secret[GNUTLS_MASTER_SIZE];
 486   uint8_t client_random[GNUTLS_RANDOM_SIZE];
 487   uint8_t server_random[GNUTLS_RANDOM_SIZE];
 488   uint8_t session_id[TLS_MAX_SESSION_ID_SIZE];
 489   uint8_t session_id_size;
 490   time_t timestamp;
 491
 492   /* The send size is the one requested by the programmer.
 493    * The recv size is the one negotiated with the peer.
 494    */
 495   uint16_t max_record_send_size;
 496   uint16_t max_record_recv_size;
 497   /* holds the negotiated certificate type */
 498   gnutls_certificate_type_t cert_type;
 499   gnutls_ecc_curve_t ecc_curve; /* holds the first supported ECC curve requested by client */
 500   gnutls_protocol_t version;    /* moved here */
 501
 502   /* Holds the signature algorithm used in this session - If any */
 503   gnutls_sign_algorithm_t sign_algo;
 504
 505   /* FIXME: The following are not saved in the session storage
 506    * for session resumption.
 507    */
 508
 509   /* Used by extensions that enable supplemental data: Which ones
 510    * do that? Do they belong in security parameters?
 511    */
 512   int do_recv_supplemental, do_send_supplemental;
 513 } security_parameters_st;
 514
 515 struct record_state_st
 516 {
 517   gnutls_datum_t mac_secret;
 518   gnutls_datum_t IV;
 519   gnutls_datum_t key;
 520   auth_cipher_hd_st cipher_state;
 521   comp_hd_st compression_state;
 522   uint64 sequence_number;
 523 };
 524
 525 /* These are used to resolve relative epochs. These values are just
 526    outside the 16 bit range to prevent off-by-one errors. An absolute
 527    epoch may be referred to by its numeric id in the range
 528    0x0000-0xffff. */
 529 #define EPOCH_READ_CURRENT  70000
 530 #define EPOCH_WRITE_CURRENT 70001
 531 #define EPOCH_NEXT          70002
 532
 533 struct record_parameters_st
 534 {
 535   uint16_t epoch;
 536   int initialized;
 537
 538   gnutls_cipher_algorithm_t cipher_algorithm;
 539   gnutls_mac_algorithm_t mac_algorithm;
 540   gnutls_compression_method_t compression_algorithm;
 541
 542   /* for DTLS */
 543   uint64_t record_sw[DTLS_RECORD_WINDOW_SIZE];
 544   unsigned int record_sw_size;
 545
 546   record_state_st read;
 547   record_state_st write;
 548
 549   /* Whether this state is in use, i.e., if there is
 550      a pending handshake message waiting to be encrypted
 551      under this epoch's parameters.
 552    */
 553   int usage_cnt;
 554 };
 555
 556 typedef struct
 557 {
 558   unsigned int priority[MAX_ALGOS];
 559   unsigned int algorithms;
 560 } priority_st;
 561
 562 typedef enum
 563 {
 564   SR_DISABLED,
 565   SR_UNSAFE,
 566   SR_PARTIAL,
 567   SR_SAFE
 568 } safe_renegotiation_t;
 569
 570 /* For the external api */
 571 struct gnutls_priority_st
 572 {
 573   priority_st cipher;
 574   priority_st mac;
 575   priority_st kx;
 576   priority_st compression;
 577   priority_st protocol;
 578   priority_st cert_type;
 579   priority_st sign_algo;
 580   priority_st supported_ecc;
 581
 582   /* to disable record padding */
 583   unsigned int no_extensions:1;
 584   unsigned int no_padding:1;
 585   unsigned int allow_large_records:1;
 586   safe_renegotiation_t sr;
 587   unsigned int ssl3_record_version:1;
 588   unsigned int server_precedence:1;
 589   unsigned int additional_verify_flags;
 590 };
 591
 592
 593 /* DH and RSA parameters types.
 594  */
 595 typedef struct gnutls_dh_params_int
 596 {
 597   /* [0] is the prime, [1] is the generator.
 598    */
 599   bigint_t params[2];
 600   int q_bits; /* length of q in bits. If zero then length is unknown.
 601               */
 602 } dh_params_st;
 603
 604 typedef struct
 605 {
 606   gnutls_dh_params_t dh_params;
 607   int free_dh_params;
 608   gnutls_rsa_params_t rsa_params;
 609   int free_rsa_params;
 610 } internal_params_st;
 611
 612 /* DTLS session state
 613  */
 614 typedef struct
 615 {
 616   /* HelloVerifyRequest DOS prevention cookie */
 617   uint8_t  cookie[DTLS_MAX_COOKIE_SIZE];
 618   uint8_t cookie_len;
 619
 620   /* For DTLS handshake fragmentation and reassembly. */
 621   uint16_t hsk_write_seq;
 622   /* the sequence number of the expected packet */
 623   unsigned int hsk_read_seq;
 624   uint16_t mtu;
 625
 626   /* a flight transmission is in process */
 627   unsigned int flight_init:1;
 628   /* whether this is the last flight in the protocol  */
 629   unsigned int last_flight:1;
 630
 631   /* the retransmission timeout in milliseconds */
 632   unsigned int retrans_timeout_ms;
 633   /* the connection timeout in milliseconds */
 634   unsigned int total_timeout_ms;
 635
 636   unsigned int hsk_hello_verify_requests;
 637
 638   /* non blocking stuff variables */
 639   unsigned int blocking:1;
 640   /* starting time of current handshake */
 641   struct timespec handshake_start_time;
 642
 643   /* The actual retrans_timeout for the next message (e.g. doubled or so)
 644    */
 645   unsigned int actual_retrans_timeout_ms;
 646
 647   /* timers to handle async handshake after gnutls_handshake()
 648    * has terminated. Required to handle retransmissions.
 649    */
 650   time_t async_term;
 651
 652   /* last retransmission triggered by record layer */
 653   struct timespec last_retransmit;
 654   unsigned int packets_dropped;
 655 } dtls_st;
 656
 657
 658 typedef union
 659 {
 660   void *ptr;
 661   uint32_t num;
 662 } extension_priv_data_t;
 663
 664 typedef struct
 665 {
 666   /* holds all the parsed data received by the record layer */
 667   mbuffer_head_st record_buffer;
 668
 669   int handshake_hash_buffer_prev_len;           /* keeps the length of handshake_hash_buffer, excluding
 670                                                  * the last received message */
 671   gnutls_buffer_st handshake_hash_buffer;       /* used to keep the last received handshake
 672                                                  * message */
 673   unsigned int resumable:1;              /* TRUE or FALSE - if we can resume that session */
 674   unsigned int ticket_sent:1;            /* whether a session ticket was sent */
 675   handshake_state_t handshake_state;    /* holds
 676                                          * a number which indicates where
 677                                          * the handshake procedure has been
 678                                          * interrupted. If it is 0 then
 679                                          * no interruption has happened.
 680                                          */
 681
 682   int invalid_connection:1;     /* true or FALSE - if this session is valid */
 683
 684   int may_not_read:1;           /* if it's 0 then we can read/write, otherwise it's forbiden to read/write
 685                                  */
 686   int may_not_write:1;
 687   int read_eof:1;               /* non-zero if we have received a closure alert. */
 688
 689   int last_alert;               /* last alert received */
 690
 691   /* The last handshake messages sent or received.
 692    */
 693   int last_handshake_in;
 694   int last_handshake_out;
 695
 696   /* priorities */
 697   struct gnutls_priority_st priorities;
 698
 699   /* resumed session */
 700   unsigned int resumed:1;  /* RESUME_TRUE or FALSE - if we are resuming a session */
 701   unsigned int resumption_requested:1; /* non-zero if resumption was requested by client */
 702   security_parameters_st resumed_security_parameters;
 703
 704   /* These buffers are used in the handshake
 705    * protocol only. freed using _gnutls_handshake_io_buffer_clear();
 706    */
 707   mbuffer_head_st handshake_send_buffer;
 708   handshake_buffer_st handshake_recv_buffer[MAX_HANDSHAKE_MSGS];
 709   int handshake_recv_buffer_size;
 710
 711   /* this buffer holds a record packet -mostly used for
 712    * non blocking IO.
 713    */
 714   mbuffer_head_st record_recv_buffer;   /* buffer holding the unparsed record that is currently
 715                                          * being received */
 716   mbuffer_head_st record_send_buffer;   /* holds cached data
 717                                          * for the gnutls_io_write_buffered()
 718                                          * function.
 719                                          */
 720   size_t record_send_buffer_user_size;  /* holds the
 721                                          * size of the user specified data to
 722                                          * send.
 723                                          */
 724
 725   int expire_time;              /* after expire_time seconds this session will expire */
 726   struct mod_auth_st_int *auth_struct;  /* used in handshake packets and KX algorithms */
 727
 728   /* this is the highest version available
 729    * to the peer. (advertized version).
 730    * This is obtained by the Handshake Client Hello
 731    * message. (some implementations read the Record version)
 732    */
 733   uint8_t adv_version_major;
 734   uint8_t adv_version_minor;
 735
 736   /* if this is non zero a certificate request message
 737    * will be sent to the client. - only if the ciphersuite
 738    * supports it.
 739    */
 740   int send_cert_req;
 741
 742   /* bits to use for DHE and DHA
 743    * use _gnutls_dh_get_prime_bits() and gnutls_dh_set_prime_bits()
 744    * to access it.
 745    */
 746   uint16_t dh_prime_bits;
 747
 748   size_t max_handshake_data_buffer_size;
 749
 750   /* PUSH & PULL functions.
 751    */
 752   gnutls_pull_timeout_func pull_timeout_func;
 753   gnutls_pull_func pull_func;
 754   gnutls_push_func push_func;
 755   gnutls_vec_push_func vec_push_func;
 756   gnutls_errno_func errno_func;
 757   /* Holds the first argument of PUSH and PULL
 758    * functions;
 759    */
 760   gnutls_transport_ptr_t transport_recv_ptr;
 761   gnutls_transport_ptr_t transport_send_ptr;
 762
 763   /* STORE & RETRIEVE functions. Only used if other
 764    * backend than gdbm is used.
 765    */
 766   gnutls_db_store_func db_store_func;
 767   gnutls_db_retr_func db_retrieve_func;
 768   gnutls_db_remove_func db_remove_func;
 769   void *db_ptr;
 770
 771   /* post client hello callback (server side only)
 772    */
 773   gnutls_handshake_post_client_hello_func user_hello_func;
 774
 775   /* holds the selected certificate and key.
 776    * use _gnutls_selected_certs_deinit() and _gnutls_selected_certs_set()
 777    * to change them.
 778    */
 779   gnutls_pcert_st *selected_cert_list;
 780   int selected_cert_list_length;
 781   struct gnutls_privkey_st *selected_key;
 782   int selected_need_free:1;
 783
 784   /* holds the extensions we sent to the peer
 785    * (in case of a client)
 786    */
 787   uint16_t extensions_sent[MAX_EXT_TYPES];
 788   uint16_t extensions_sent_size;
 789
 790   /* is 0 if we are to send the whole PGP key, or non zero
 791    * if the fingerprint is to be sent.
 792    */
 793   int pgp_fingerprint;
 794
 795   /* This holds the default version that our first
 796    * record packet will have. */
 797   uint8_t default_record_version[2];
 798
 799   void *user_ptr;
 800
 801   int enable_private;           /* non zero to
 802                                  * enable cipher suites
 803                                  * which have 0xFF status.
 804                                  */
 805
 806   /* Holds 0 if the last called function was interrupted while
 807    * receiving, and non zero otherwise.
 808    */
 809   int direction;
 810
 811   /* This callback will be used (if set) to receive an
 812    * openpgp key. (if the peer sends a fingerprint)
 813    */
 814   gnutls_openpgp_recv_key_func openpgp_recv_key_func;
 815
 816   /* If non zero the server will not advertise the CA's he
 817    * trusts (do not send an RDN sequence).
 818    */
 819   int ignore_rdn_sequence;
 820
 821   /* This is used to set an arbitary version in the RSA
 822    * PMS secret. Can be used by clients to test whether the
 823    * server checks that version. (** only used in gnutls-cli-debug)
 824    */
 825   uint8_t rsa_pms_version[2];
 826
 827   /* Here we cache the DH or RSA parameters got from the
 828    * credentials structure, or from a callback. That is to
 829    * minimize external calls.
 830    */
 831   internal_params_st params;
 832
 833   /* To avoid using global variables, and especially on Windows where
 834    * the application may use a different errno variable than GnuTLS,
 835    * it is possible to use gnutls_transport_set_errno to set a
 836    * session-specific errno variable in the user-replaceable push/pull
 837    * functions.  This value is used by the send/recv functions.  (The
 838    * strange name of this variable is because 'errno' is typically
 839    * #define'd.)
 840    */
 841   int errnum;
 842
 843   /* Function used to perform public-key signing operation during
 844      handshake.  Used by gnutls_sig.c:_gnutls_tls_sign(), see also
 845      gnutls_sign_callback_set(). */
 846   gnutls_sign_func sign_func;
 847   void *sign_func_userdata;
 848
 849   /* minimum bits to allow for SRP
 850    * use gnutls_srp_set_prime_bits() to adjust it.
 851    */
 852   uint16_t srp_prime_bits;
 853
 854   /* A handshake process has been completed */
 855   unsigned int initial_negotiation_completed:1;
 856
 857   struct
 858   {
 859     uint16_t type;
 860     extension_priv_data_t priv;
 861     int set:1;
 862   } extension_int_data[MAX_EXT_TYPES];
 863
 864   struct
 865   {
 866     uint16_t type;
 867     extension_priv_data_t priv;
 868     int set:1;
 869   } resumed_extension_int_data[MAX_EXT_TYPES];
 870   /* The type of transport protocol; stream or datagram */
 871   transport_t transport;
 872
 873   /* DTLS session state */
 874   dtls_st dtls;
 875
 876   /* if set it means that the master key was set using
 877    * gnutls_session_set_master() rather than being negotiated. */
 878   unsigned int premaster_set:1;
 879
 880   unsigned int cb_tls_unique_len;
 881   unsigned char cb_tls_unique[MAX_VERIFY_DATA_SIZE];
 882
 883   unsigned int handshake_endtime; /* end time in seconds */
 884   unsigned int handshake_timeout_ms; /* timeout in milliseconds */
 885
 886   /* If you add anything here, check _gnutls_handshake_internal_state_clear().
 887    */
 888 } internals_st;
 889
 890 /* Maximum number of epochs we keep around. */
 891 #define MAX_EPOCH_INDEX 16
 892
 893 struct gnutls_session_int
 894 {
 895   security_parameters_st security_parameters;
 896   record_parameters_st *record_parameters[MAX_EPOCH_INDEX];
 897   internals_st internals;
 898   gnutls_key_st key;
 899 };
 900
 901
 902 /* functions
 903  */
 904 void _gnutls_free_auth_info (gnutls_session_t session);
 905
 906 /* These two macros return the advertised TLS version of
 907  * the peer.
 908  */
 909 #define _gnutls_get_adv_version_major( session) \
 910         session->internals.adv_version_major
 911
 912 #define _gnutls_get_adv_version_minor( session) \
 913         session->internals.adv_version_minor
 914
 915 #define set_adv_version( session, major, minor) \
 916         session->internals.adv_version_major = major; \
 917         session->internals.adv_version_minor = minor
 918
 919 void _gnutls_set_adv_version (gnutls_session_t, gnutls_protocol_t);
 920 gnutls_protocol_t _gnutls_get_adv_version (gnutls_session_t);
 921
 922 int _gnutls_is_secure_mem_null (const void *);
 923
 924 inline static gnutls_protocol_t
 925 _gnutls_protocol_get_version (gnutls_session_t session)
 926 {
 927   return session->security_parameters.version;
 928 }
 929
 930 #define gnutls_protocol_get_version _gnutls_protocol_get_version
 931
 932 inline static void
 933 _gnutls_set_current_version (gnutls_session_t session,
 934                              gnutls_protocol_t version)
 935 {
 936   session->security_parameters.version = version;
 937 }
 938
 939
 940 #endif /* GNUTLS_INT_H */