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