ssl/record/record.h

   1 /*
   2  * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (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 structures should be considered PRIVATE to the record layer. No     *
  13  * non-record layer code should be using these structures in any way.        *
  14  *                                                                           *
  15  *****************************************************************************/
  16
  17 typedef struct ssl3_buffer_st {
  18     /* at least SSL3_RT_MAX_PACKET_SIZE bytes, see ssl3_setup_buffers() */
  19     unsigned char *buf;
  20     /* default buffer size (or 0 if no default set) */
  21     size_t default_len;
  22     /* buffer size */
  23     size_t len;
  24     /* where to 'copy from' */
  25     size_t offset;
  26     /* how many bytes left */
  27     size_t left;
  28     /* 'buf' is from application for KTLS */
  29     int app_buffer;
  30 } SSL3_BUFFER;
  31
  32 #define SEQ_NUM_SIZE                            8
  33
  34 typedef struct ssl3_record_st {
  35     /* Record layer version */
  36     /* r */
  37     int rec_version;
  38     /* type of record */
  39     /* r */
  40     int type;
  41     /* How many bytes available */
  42     /* rw */
  43     size_t length;
  44     /*
  45      * How many bytes were available before padding was removed? This is used
  46      * to implement the MAC check in constant time for CBC records.
  47      */
  48     /* rw */
  49     size_t orig_len;
  50     /* read/write offset into 'buf' */
  51     /* r */
  52     size_t off;
  53     /* pointer to the record data */
  54     /* rw */
  55     unsigned char *data;
  56     /* where the decode bytes are */
  57     /* rw */
  58     unsigned char *input;
  59     /* only used with decompression - malloc()ed */
  60     /* r */
  61     unsigned char *comp;
  62     /* Whether the data from this record has already been read or not */
  63     /* r */
  64     unsigned int read;
  65     /* epoch number, needed by DTLS1 */
  66     /* r */
  67     unsigned long epoch;
  68     /* sequence number, needed by DTLS1 */
  69     /* r */
  70     unsigned char seq_num[SEQ_NUM_SIZE];
  71 } SSL3_RECORD;
  72
  73 typedef struct dtls1_bitmap_st {
  74     /* Track 32 packets on 32-bit systems and 64 - on 64-bit systems */
  75     unsigned long map;
  76     /* Max record number seen so far, 64-bit value in big-endian encoding */
  77     unsigned char max_seq_num[SEQ_NUM_SIZE];
  78 } DTLS1_BITMAP;
  79
  80 typedef struct record_pqueue_st {
  81     unsigned short epoch;
  82     struct pqueue_st *q;
  83 } record_pqueue;
  84
  85 typedef struct dtls1_record_data_st {
  86     unsigned char *packet;
  87     size_t packet_length;
  88     SSL3_BUFFER rbuf;
  89     SSL3_RECORD rrec;
  90 #ifndef OPENSSL_NO_SCTP
  91     struct bio_dgram_sctp_rcvinfo recordinfo;
  92 #endif
  93 } DTLS1_RECORD_DATA;
  94
  95 typedef struct dtls_record_layer_st {
  96     /*
  97      * The current data and handshake epoch.  This is initially
  98      * undefined, and starts at zero once the initial handshake is
  99      * completed
 100      */
 101     unsigned short r_epoch;
 102     unsigned short w_epoch;
 103     /* records being received in the current epoch */
 104     DTLS1_BITMAP bitmap;
 105     /* renegotiation starts a new set of sequence numbers */
 106     DTLS1_BITMAP next_bitmap;
 107     /* Received handshake records (processed and unprocessed) */
 108     record_pqueue unprocessed_rcds;
 109     record_pqueue processed_rcds;
 110     /*
 111      * Buffered application records. Only for records between CCS and
 112      * Finished to prevent either protocol violation or unnecessary message
 113      * loss.
 114      */
 115     record_pqueue buffered_app_data;
 116     /* save last and current sequence numbers for retransmissions */
 117     unsigned char last_write_sequence[8];
 118     unsigned char curr_write_sequence[8];
 119 } DTLS_RECORD_LAYER;
 120
 121 /*****************************************************************************
 122  *                                                                           *
 123  * This structure should be considered "opaque" to anything outside of the   *
 124  * record layer. No non-record layer code should be accessing the members of *
 125  * this structure.                                                           *
 126  *                                                                           *
 127  *****************************************************************************/
 128
 129 typedef struct record_layer_st {
 130     /* The parent SSL structure */
 131     SSL *s;
 132     /*
 133      * Read as many input bytes as possible (for
 134      * non-blocking reads)
 135      */
 136     int read_ahead;
 137     /* where we are when reading */
 138     int rstate;
 139     /* How many pipelines can be used to read data */
 140     size_t numrpipes;
 141     /* How many pipelines can be used to write data */
 142     size_t numwpipes;
 143     /* read IO goes into here */
 144     SSL3_BUFFER rbuf;
 145     /* write IO goes into here */
 146     SSL3_BUFFER wbuf[SSL_MAX_PIPELINES];
 147     /* each decoded record goes in here */
 148     SSL3_RECORD rrec[SSL_MAX_PIPELINES];
 149     /* used internally to point at a raw packet */
 150     unsigned char *packet;
 151     size_t packet_length;
 152     /* number of bytes sent so far */
 153     size_t wnum;
 154     unsigned char handshake_fragment[4];
 155     size_t handshake_fragment_len;
 156     /* The number of consecutive empty records we have received */
 157     size_t empty_record_count;
 158     /* partial write - check the numbers match */
 159     /* number bytes written */
 160     size_t wpend_tot;
 161     int wpend_type;
 162     /* number of bytes submitted */
 163     size_t wpend_ret;
 164     const unsigned char *wpend_buf;
 165     unsigned char read_sequence[SEQ_NUM_SIZE];
 166     unsigned char write_sequence[SEQ_NUM_SIZE];
 167     /* Set to true if this is the first record in a connection */
 168     unsigned int is_first_record;
 169     /* Count of the number of consecutive warning alerts received */
 170     unsigned int alert_count;
 171     DTLS_RECORD_LAYER *d;
 172 } RECORD_LAYER;
 173
 174 /*****************************************************************************
 175  *                                                                           *
 176  * The following macros/functions represent the libssl internal API to the   *
 177  * record layer. Any libssl code may call these functions/macros             *
 178  *                                                                           *
 179  *****************************************************************************/
 180
 181 #define MIN_SSL2_RECORD_LEN     9
 182
 183 #define RECORD_LAYER_set_read_ahead(rl, ra)     ((rl)->read_ahead = (ra))
 184 #define RECORD_LAYER_get_read_ahead(rl)         ((rl)->read_ahead)
 185 #define RECORD_LAYER_get_packet(rl)             ((rl)->packet)
 186 #define RECORD_LAYER_get_packet_length(rl)      ((rl)->packet_length)
 187 #define RECORD_LAYER_add_packet_length(rl, inc) ((rl)->packet_length += (inc))
 188 #define DTLS_RECORD_LAYER_get_w_epoch(rl)       ((rl)->d->w_epoch)
 189 #define DTLS_RECORD_LAYER_get_processed_rcds(rl) \
 190                                                 ((rl)->d->processed_rcds)
 191 #define DTLS_RECORD_LAYER_get_unprocessed_rcds(rl) \
 192                                                 ((rl)->d->unprocessed_rcds)
 193 #define RECORD_LAYER_get_rbuf(rl)               (&(rl)->rbuf)
 194 #define RECORD_LAYER_get_wbuf(rl)               ((rl)->wbuf)
 195
 196 void RECORD_LAYER_init(RECORD_LAYER *rl, SSL *s);
 197 void RECORD_LAYER_clear(RECORD_LAYER *rl);
 198 void RECORD_LAYER_release(RECORD_LAYER *rl);
 199 int RECORD_LAYER_read_pending(const RECORD_LAYER *rl);
 200 int RECORD_LAYER_processed_read_pending(const RECORD_LAYER *rl);
 201 int RECORD_LAYER_write_pending(const RECORD_LAYER *rl);
 202 void RECORD_LAYER_reset_read_sequence(RECORD_LAYER *rl);
 203 void RECORD_LAYER_reset_write_sequence(RECORD_LAYER *rl);
 204 int RECORD_LAYER_is_sslv2_record(RECORD_LAYER *rl);
 205 size_t RECORD_LAYER_get_rrec_length(RECORD_LAYER *rl);
 206 __owur size_t ssl3_pending(const SSL *s);
 207 __owur int ssl3_write_bytes(SSL *s, int type, const void *buf, size_t len,
 208                             size_t *written);
 209 int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 210                   size_t *pipelens, size_t numpipes,
 211                   int create_empty_fragment, size_t *written);
 212 __owur int ssl3_read_bytes(SSL *s, int type, int *recvd_type,
 213                            unsigned char *buf, size_t len, int peek,
 214                            size_t *readbytes);
 215 __owur int ssl3_setup_buffers(SSL *s);
 216 __owur int ssl3_enc(SSL *s, SSL3_RECORD *inrecs, size_t n_recs, int send);
 217 __owur int n_ssl3_mac(SSL *ssl, SSL3_RECORD *rec, unsigned char *md, int send);
 218 __owur int ssl3_write_pending(SSL *s, int type, const unsigned char *buf, size_t len,
 219                               size_t *written);
 220 __owur int tls1_enc(SSL *s, SSL3_RECORD *recs, size_t n_recs, int send);
 221 __owur int tls1_mac(SSL *ssl, SSL3_RECORD *rec, unsigned char *md, int send);
 222 __owur int tls13_enc(SSL *s, SSL3_RECORD *recs, size_t n_recs, int send);
 223 int DTLS_RECORD_LAYER_new(RECORD_LAYER *rl);
 224 void DTLS_RECORD_LAYER_free(RECORD_LAYER *rl);
 225 void DTLS_RECORD_LAYER_clear(RECORD_LAYER *rl);
 226 void DTLS_RECORD_LAYER_set_saved_w_epoch(RECORD_LAYER *rl, unsigned short e);
 227 void DTLS_RECORD_LAYER_clear(RECORD_LAYER *rl);
 228 void DTLS_RECORD_LAYER_set_write_sequence(RECORD_LAYER *rl, unsigned char *seq);
 229 __owur int dtls1_read_bytes(SSL *s, int type, int *recvd_type,
 230                             unsigned char *buf, size_t len, int peek,
 231                             size_t *readbytes);
 232 __owur int dtls1_write_bytes(SSL *s, int type, const void *buf, size_t len,
 233                              size_t *written);
 234 int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
 235                    size_t len, int create_empty_fragment, size_t *written);
 236 void dtls1_reset_seq_numbers(SSL *s, int rw);
 237 int dtls_buffer_listen_record(SSL *s, size_t len, unsigned char *seq,
 238                               size_t off);