1/*
2 * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the OpenSSL license (the "License").  You may not use
5 * this file except in compliance with the License.  You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10/*****************************************************************************
11 *                                                                           *
12 * These 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
17typedef 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
34typedef 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
73typedef 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
80typedef struct record_pqueue_st {
81    unsigned short epoch;
82    struct pqueue_st *q;
83} record_pqueue;
84
85typedef 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
95typedef 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
129typedef 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
196void RECORD_LAYER_init(RECORD_LAYER *rl, SSL *s);
197void RECORD_LAYER_clear(RECORD_LAYER *rl);
198void RECORD_LAYER_release(RECORD_LAYER *rl);
199int RECORD_LAYER_read_pending(const RECORD_LAYER *rl);
200int RECORD_LAYER_processed_read_pending(const RECORD_LAYER *rl);
201int RECORD_LAYER_write_pending(const RECORD_LAYER *rl);
202void RECORD_LAYER_reset_read_sequence(RECORD_LAYER *rl);
203void RECORD_LAYER_reset_write_sequence(RECORD_LAYER *rl);
204int RECORD_LAYER_is_sslv2_record(RECORD_LAYER *rl);
205size_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);
209int 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);
223int DTLS_RECORD_LAYER_new(RECORD_LAYER *rl);
224void DTLS_RECORD_LAYER_free(RECORD_LAYER *rl);
225void DTLS_RECORD_LAYER_clear(RECORD_LAYER *rl);
226void DTLS_RECORD_LAYER_set_saved_w_epoch(RECORD_LAYER *rl, unsigned short e);
227void DTLS_RECORD_LAYER_clear(RECORD_LAYER *rl);
228void 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);
234int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
235                   size_t len, int create_empty_fragment, size_t *written);
236void dtls1_reset_seq_numbers(SSL *s, int rw);
237int dtls_buffer_listen_record(SSL *s, size_t len, unsigned char *seq,
238                              size_t off);
239