xref: /freebsd/crypto/openssl/ssl/record/methods/recmethod_local.h (revision f25b8c9fb4f58cf61adb47d7570abe7caa6d385d)
1 /*
2  * Copyright 2022-2024 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 #include <openssl/bio.h>
11 #include <openssl/ssl.h>
12 #include <openssl/err.h>
13 #include "../../ssl_local.h"
14 #include "../record_local.h"
15 
16 typedef struct dtls_bitmap_st {
17     /* Track 64 packets */
18     uint64_t map;
19     /* Max record number seen so far, 64-bit value in big-endian encoding */
20     unsigned char max_seq_num[SEQ_NUM_SIZE];
21 } DTLS_BITMAP;
22 
23 typedef struct ssl_mac_buf_st {
24     unsigned char *mac;
25     int alloced;
26 } SSL_MAC_BUF;
27 
28 typedef struct tls_buffer_st {
29     /* at least SSL3_RT_MAX_PACKET_SIZE bytes */
30     unsigned char *buf;
31     /* default buffer size (or 0 if no default set) */
32     size_t default_len;
33     /* buffer size */
34     size_t len;
35     /* where to 'copy from' */
36     size_t offset;
37     /* how many bytes left */
38     size_t left;
39     /* 'buf' is from application for KTLS */
40     int app_buffer;
41     /* The type of data stored in this buffer. Only used for writing */
42     int type;
43 } TLS_BUFFER;
44 
45 typedef struct tls_rl_record_st {
46     /* Record layer version */
47     /* r */
48     int rec_version;
49     /* type of record */
50     /* r */
51     int type;
52     /* How many bytes available */
53     /* rw */
54     size_t length;
55     /*
56      * How many bytes were available before padding was removed? This is used
57      * to implement the MAC check in constant time for CBC records.
58      */
59     /* rw */
60     size_t orig_len;
61     /* read/write offset into 'buf' */
62     /* r */
63     size_t off;
64     /* pointer to the record data */
65     /* rw */
66     unsigned char *data;
67     /* where the decode bytes are */
68     /* rw */
69     unsigned char *input;
70     /* only used with decompression - malloc()ed */
71     /* r */
72     unsigned char *comp;
73     /* epoch number, needed by DTLS1 */
74     /* r */
75     uint16_t epoch;
76     /* sequence number, needed by DTLS1 */
77     /* r */
78     unsigned char seq_num[SEQ_NUM_SIZE];
79 } TLS_RL_RECORD;
80 
81 /* Macros/functions provided by the TLS_RL_RECORD component */
82 
83 #define TLS_RL_RECORD_set_type(r, t) ((r)->type = (t))
84 #define TLS_RL_RECORD_set_rec_version(r, v) ((r)->rec_version = (v))
85 #define TLS_RL_RECORD_get_length(r) ((r)->length)
86 #define TLS_RL_RECORD_set_length(r, l) ((r)->length = (l))
87 #define TLS_RL_RECORD_add_length(r, l) ((r)->length += (l))
88 #define TLS_RL_RECORD_set_data(r, d) ((r)->data = (d))
89 #define TLS_RL_RECORD_set_input(r, i) ((r)->input = (i))
90 #define TLS_RL_RECORD_reset_input(r) ((r)->input = (r)->data)
91 
92 /* Protocol version specific function pointers */
93 struct record_functions_st {
94     /*
95      * Returns either OSSL_RECORD_RETURN_SUCCESS, OSSL_RECORD_RETURN_FATAL or
96      * OSSL_RECORD_RETURN_NON_FATAL_ERR if we can keep trying to find an
97      * alternative record layer.
98      */
99     int (*set_crypto_state)(OSSL_RECORD_LAYER *rl, int level,
100         unsigned char *key, size_t keylen,
101         unsigned char *iv, size_t ivlen,
102         unsigned char *mackey, size_t mackeylen,
103         const EVP_CIPHER *ciph,
104         size_t taglen,
105         int mactype,
106         const EVP_MD *md,
107         COMP_METHOD *comp);
108 
109     /*
110      * Returns:
111      *    0: if the record is publicly invalid, or an internal error, or AEAD
112      *       decryption failed, or EtM decryption failed.
113      *    1: Success or MtE decryption failed (MAC will be randomised)
114      */
115     int (*cipher)(OSSL_RECORD_LAYER *rl, TLS_RL_RECORD *recs, size_t n_recs,
116         int sending, SSL_MAC_BUF *macs, size_t macsize);
117     /* Returns 1 for success or 0 for error */
118     int (*mac)(OSSL_RECORD_LAYER *rl, TLS_RL_RECORD *rec, unsigned char *md,
119         int sending);
120 
121     /* Return 1 for success or 0 for error */
122     int (*set_protocol_version)(OSSL_RECORD_LAYER *rl, int version);
123 
124     /* Read related functions */
125 
126     int (*read_n)(OSSL_RECORD_LAYER *rl, size_t n, size_t max, int extend,
127         int clearold, size_t *readbytes);
128 
129     int (*get_more_records)(OSSL_RECORD_LAYER *rl);
130 
131     /* Return 1 for success or 0 for error */
132     int (*validate_record_header)(OSSL_RECORD_LAYER *rl, TLS_RL_RECORD *rec);
133 
134     /* Return 1 for success or 0 for error */
135     int (*post_process_record)(OSSL_RECORD_LAYER *rl, TLS_RL_RECORD *rec);
136 
137     /* Write related functions */
138 
139     size_t (*get_max_records)(OSSL_RECORD_LAYER *rl, uint8_t type, size_t len,
140         size_t maxfrag, size_t *preffrag);
141 
142     /* Return 1 for success or 0 for error */
143     int (*write_records)(OSSL_RECORD_LAYER *rl, OSSL_RECORD_TEMPLATE *templates,
144         size_t numtempl);
145 
146     /* Allocate the rl->wbuf buffers. Return 1 for success or 0 for error */
147     int (*allocate_write_buffers)(OSSL_RECORD_LAYER *rl,
148         OSSL_RECORD_TEMPLATE *templates,
149         size_t numtempl, size_t *prefix);
150 
151     /*
152      * Initialise the packets in the |pkt| array using the buffers in |rl->wbuf|.
153      * Some protocol versions may use the space in |prefixtempl| to add
154      * an artificial template in front of the |templates| array and hence may
155      * initialise 1 more WPACKET than there are templates. |*wpinited|
156      * returns the number of WPACKETs in |pkt| that were successfully
157      * initialised. This must be 0 on entry and will be filled in even on error.
158      */
159     int (*initialise_write_packets)(OSSL_RECORD_LAYER *rl,
160         OSSL_RECORD_TEMPLATE *templates,
161         size_t numtempl,
162         OSSL_RECORD_TEMPLATE *prefixtempl,
163         WPACKET *pkt,
164         TLS_BUFFER *bufs,
165         size_t *wpinited);
166 
167     /* Get the actual record type to be used for a given template */
168     uint8_t (*get_record_type)(OSSL_RECORD_LAYER *rl,
169         OSSL_RECORD_TEMPLATE *template);
170 
171     /* Write the record header data to the WPACKET */
172     int (*prepare_record_header)(OSSL_RECORD_LAYER *rl, WPACKET *thispkt,
173         OSSL_RECORD_TEMPLATE *templ,
174         uint8_t rectype,
175         unsigned char **recdata);
176 
177     int (*add_record_padding)(OSSL_RECORD_LAYER *rl,
178         OSSL_RECORD_TEMPLATE *thistempl,
179         WPACKET *thispkt,
180         TLS_RL_RECORD *thiswr);
181 
182     /*
183      * This applies any mac that might be necessary, ensures that we have enough
184      * space in the WPACKET to perform the encryption and sets up the
185      * TLS_RL_RECORD ready for that encryption.
186      */
187     int (*prepare_for_encryption)(OSSL_RECORD_LAYER *rl,
188         size_t mac_size,
189         WPACKET *thispkt,
190         TLS_RL_RECORD *thiswr);
191 
192     /*
193      * Any updates required to the record after encryption has been applied. For
194      * example, adding a MAC if using encrypt-then-mac
195      */
196     int (*post_encryption_processing)(OSSL_RECORD_LAYER *rl,
197         size_t mac_size,
198         OSSL_RECORD_TEMPLATE *thistempl,
199         WPACKET *thispkt,
200         TLS_RL_RECORD *thiswr);
201 
202     /*
203      * Some record layer implementations need to do some custom preparation of
204      * the BIO before we write to it. KTLS does this to prevent coalescing of
205      * control and data messages.
206      */
207     int (*prepare_write_bio)(OSSL_RECORD_LAYER *rl, int type);
208 };
209 
210 struct ossl_record_layer_st {
211     OSSL_LIB_CTX *libctx;
212     const char *propq;
213     int isdtls;
214     int version;
215     int role;
216     int direction;
217     int level;
218     const EVP_MD *md;
219     /* DTLS only */
220     uint16_t epoch;
221 
222     /*
223      * A BIO containing any data read in the previous epoch that was destined
224      * for this epoch
225      */
226     BIO *prev;
227 
228     /* The transport BIO */
229     BIO *bio;
230 
231     /*
232      * A BIO where we will send any data read by us that is destined for the
233      * next epoch.
234      */
235     BIO *next;
236 
237     /* Types match the equivalent fields in the SSL object */
238     uint64_t options;
239     uint32_t mode;
240 
241     /* write IO goes into here */
242     TLS_BUFFER wbuf[SSL_MAX_PIPELINES + 1];
243 
244     /* Next wbuf with pending data still to write */
245     size_t nextwbuf;
246 
247     /* How many pipelines can be used to write data */
248     size_t numwpipes;
249 
250     /* read IO goes into here */
251     TLS_BUFFER rbuf;
252     /* each decoded record goes in here */
253     TLS_RL_RECORD rrec[SSL_MAX_PIPELINES];
254 
255     /* How many records have we got available in the rrec buffer */
256     size_t num_recs;
257 
258     /* The record number in the rrec buffer that can be read next */
259     size_t curr_rec;
260 
261     /* The number of records that have been released via tls_release_record */
262     size_t num_released;
263 
264     /* where we are when reading */
265     int rstate;
266 
267     /* used internally to point at a raw packet */
268     unsigned char *packet;
269     size_t packet_length;
270 
271     /* Sequence number for the next record */
272     unsigned char sequence[SEQ_NUM_SIZE];
273 
274     /* Alert code to be used if an error occurs */
275     int alert;
276 
277     /*
278      * Read as many input bytes as possible (for non-blocking reads)
279      */
280     int read_ahead;
281 
282     /* The number of consecutive empty records we have received */
283     size_t empty_record_count;
284 
285     /*
286      * Do we need to send a prefix empty record before application data as a
287      * countermeasure against known-IV weakness (necessary for SSLv3 and
288      * TLSv1.0)
289      */
290     int need_empty_fragments;
291 
292     /* cryptographic state */
293     EVP_CIPHER_CTX *enc_ctx;
294 
295     /* TLSv1.3 MAC ctx, only used with integrity-only cipher */
296     EVP_MAC_CTX *mac_ctx;
297 
298     /* Explicit IV length */
299     size_t eivlen;
300 
301     /* used for mac generation */
302     EVP_MD_CTX *md_ctx;
303 
304     /* compress/uncompress */
305     COMP_CTX *compctx;
306 
307     /* Set to 1 if this is the first handshake. 0 otherwise */
308     int is_first_handshake;
309 
310     /*
311      * The smaller of the configured and negotiated maximum fragment length
312      * or SSL3_RT_MAX_PLAIN_LENGTH if none
313      */
314     unsigned int max_frag_len;
315 
316     /* The maximum amount of early data we can receive/send */
317     uint32_t max_early_data;
318 
319     /* The amount of early data that we have sent/received */
320     size_t early_data_count;
321 
322     /* TLSv1.3 record padding */
323     size_t block_padding;
324     size_t hs_padding;
325 
326     /* Only used by SSLv3 */
327     unsigned char mac_secret[EVP_MAX_MD_SIZE];
328 
329     /* TLSv1.0/TLSv1.1/TLSv1.2 */
330     int use_etm;
331 
332     /* Flags for GOST ciphers */
333     int stream_mac;
334     int tlstree;
335 
336     /* TLSv1.3 fields */
337     unsigned char *iv; /* static IV */
338     unsigned char *nonce; /* part of static IV followed by sequence number */
339     int allow_plain_alerts;
340 
341     /* TLS "any" fields */
342     /* Set to true if this is the first record in a connection */
343     unsigned int is_first_record;
344 
345     size_t taglen;
346 
347     /* DTLS received handshake records (processed and unprocessed) */
348     struct pqueue_st *unprocessed_rcds;
349     struct pqueue_st *processed_rcds;
350 
351     /* records being received in the current epoch */
352     DTLS_BITMAP bitmap;
353     /* renegotiation starts a new set of sequence numbers */
354     DTLS_BITMAP next_bitmap;
355 
356     /*
357      * Whether we are currently in a handshake or not. Only maintained for DTLS
358      */
359     int in_init;
360 
361     /* Callbacks */
362     void *cbarg;
363     OSSL_FUNC_rlayer_skip_early_data_fn *skip_early_data;
364     OSSL_FUNC_rlayer_msg_callback_fn *msg_callback;
365     OSSL_FUNC_rlayer_security_fn *security;
366     OSSL_FUNC_rlayer_padding_fn *padding;
367 
368     size_t max_pipelines;
369 
370     /* Function pointers for version specific functions */
371     const struct record_functions_st *funcs;
372 };
373 
374 typedef struct dtls_rlayer_record_data_st {
375     unsigned char *packet;
376     size_t packet_length;
377     TLS_BUFFER rbuf;
378     TLS_RL_RECORD rrec;
379 } DTLS_RLAYER_RECORD_DATA;
380 
381 extern const struct record_functions_st ssl_3_0_funcs;
382 extern const struct record_functions_st tls_1_funcs;
383 extern const struct record_functions_st tls_1_3_funcs;
384 extern const struct record_functions_st tls_any_funcs;
385 extern const struct record_functions_st dtls_1_funcs;
386 extern const struct record_functions_st dtls_any_funcs;
387 
388 void ossl_rlayer_fatal(OSSL_RECORD_LAYER *rl, int al, int reason,
389     const char *fmt, ...);
390 
391 #define RLAYERfatal(rl, al, r) RLAYERfatal_data((rl), (al), (r), NULL)
392 #define RLAYERfatal_data                                         \
393     (ERR_new(),                                                  \
394         ERR_set_debug(OPENSSL_FILE, OPENSSL_LINE, OPENSSL_FUNC), \
395         ossl_rlayer_fatal)
396 
397 #define RLAYER_USE_EXPLICIT_IV(rl) ((rl)->version == TLS1_1_VERSION \
398     || (rl)->version == TLS1_2_VERSION                              \
399     || (rl)->version == DTLS1_BAD_VER                               \
400     || (rl)->version == DTLS1_VERSION                               \
401     || (rl)->version == DTLS1_2_VERSION)
402 
403 void ossl_tls_rl_record_set_seq_num(TLS_RL_RECORD *r,
404     const unsigned char *seq_num);
405 
406 int ossl_set_tls_provider_parameters(OSSL_RECORD_LAYER *rl,
407     EVP_CIPHER_CTX *ctx,
408     const EVP_CIPHER *ciph,
409     const EVP_MD *md);
410 
411 int tls_increment_sequence_ctr(OSSL_RECORD_LAYER *rl);
412 int tls_alloc_buffers(OSSL_RECORD_LAYER *rl);
413 int tls_free_buffers(OSSL_RECORD_LAYER *rl);
414 
415 int tls_default_read_n(OSSL_RECORD_LAYER *rl, size_t n, size_t max, int extend,
416     int clearold, size_t *readbytes);
417 int tls_get_more_records(OSSL_RECORD_LAYER *rl);
418 int dtls_get_more_records(OSSL_RECORD_LAYER *rl);
419 
420 int dtls_prepare_record_header(OSSL_RECORD_LAYER *rl,
421     WPACKET *thispkt,
422     OSSL_RECORD_TEMPLATE *templ,
423     uint8_t rectype,
424     unsigned char **recdata);
425 int dtls_post_encryption_processing(OSSL_RECORD_LAYER *rl,
426     size_t mac_size,
427     OSSL_RECORD_TEMPLATE *thistempl,
428     WPACKET *thispkt,
429     TLS_RL_RECORD *thiswr);
430 
431 int tls_default_set_protocol_version(OSSL_RECORD_LAYER *rl, int version);
432 int tls_default_validate_record_header(OSSL_RECORD_LAYER *rl, TLS_RL_RECORD *re);
433 int tls_do_compress(OSSL_RECORD_LAYER *rl, TLS_RL_RECORD *wr);
434 int tls_do_uncompress(OSSL_RECORD_LAYER *rl, TLS_RL_RECORD *rec);
435 int tls_default_post_process_record(OSSL_RECORD_LAYER *rl, TLS_RL_RECORD *rec);
436 int tls13_common_post_process_record(OSSL_RECORD_LAYER *rl, TLS_RL_RECORD *rec);
437 
438 int tls_int_new_record_layer(OSSL_LIB_CTX *libctx, const char *propq, int vers,
439     int role, int direction, int level,
440     const EVP_CIPHER *ciph, size_t taglen,
441     const EVP_MD *md, COMP_METHOD *comp, BIO *prev,
442     BIO *transport, BIO *next,
443     const OSSL_PARAM *settings, const OSSL_PARAM *options,
444     const OSSL_DISPATCH *fns, void *cbarg,
445     OSSL_RECORD_LAYER **retrl);
446 int tls_free(OSSL_RECORD_LAYER *rl);
447 int tls_unprocessed_read_pending(OSSL_RECORD_LAYER *rl);
448 int tls_processed_read_pending(OSSL_RECORD_LAYER *rl);
449 size_t tls_app_data_pending(OSSL_RECORD_LAYER *rl);
450 size_t tls_get_max_records(OSSL_RECORD_LAYER *rl, uint8_t type, size_t len,
451     size_t maxfrag, size_t *preffrag);
452 int tls_write_records(OSSL_RECORD_LAYER *rl, OSSL_RECORD_TEMPLATE *templates,
453     size_t numtempl);
454 int tls_retry_write_records(OSSL_RECORD_LAYER *rl);
455 int tls_get_alert_code(OSSL_RECORD_LAYER *rl);
456 int tls_set1_bio(OSSL_RECORD_LAYER *rl, BIO *bio);
457 int tls_read_record(OSSL_RECORD_LAYER *rl, void **rechandle, int *rversion,
458     uint8_t *type, const unsigned char **data, size_t *datalen,
459     uint16_t *epoch, unsigned char *seq_num);
460 int tls_release_record(OSSL_RECORD_LAYER *rl, void *rechandle, size_t length);
461 int tls_default_set_protocol_version(OSSL_RECORD_LAYER *rl, int version);
462 int tls_set_protocol_version(OSSL_RECORD_LAYER *rl, int version);
463 void tls_set_plain_alerts(OSSL_RECORD_LAYER *rl, int allow);
464 void tls_set_first_handshake(OSSL_RECORD_LAYER *rl, int first);
465 void tls_set_max_pipelines(OSSL_RECORD_LAYER *rl, size_t max_pipelines);
466 void tls_get_state(OSSL_RECORD_LAYER *rl, const char **shortstr,
467     const char **longstr);
468 int tls_set_options(OSSL_RECORD_LAYER *rl, const OSSL_PARAM *options);
469 const COMP_METHOD *tls_get_compression(OSSL_RECORD_LAYER *rl);
470 void tls_set_max_frag_len(OSSL_RECORD_LAYER *rl, size_t max_frag_len);
471 int tls_setup_read_buffer(OSSL_RECORD_LAYER *rl);
472 int tls_setup_write_buffer(OSSL_RECORD_LAYER *rl, size_t numwpipes,
473     size_t firstlen, size_t nextlen);
474 
475 int tls_write_records_multiblock(OSSL_RECORD_LAYER *rl,
476     OSSL_RECORD_TEMPLATE *templates,
477     size_t numtempl);
478 
479 size_t tls_get_max_records_default(OSSL_RECORD_LAYER *rl, uint8_t type,
480     size_t len,
481     size_t maxfrag, size_t *preffrag);
482 size_t tls_get_max_records_multiblock(OSSL_RECORD_LAYER *rl, uint8_t type,
483     size_t len, size_t maxfrag,
484     size_t *preffrag);
485 int tls_allocate_write_buffers_default(OSSL_RECORD_LAYER *rl,
486     OSSL_RECORD_TEMPLATE *templates,
487     size_t numtempl, size_t *prefix);
488 int tls_initialise_write_packets_default(OSSL_RECORD_LAYER *rl,
489     OSSL_RECORD_TEMPLATE *templates,
490     size_t numtempl,
491     OSSL_RECORD_TEMPLATE *prefixtempl,
492     WPACKET *pkt,
493     TLS_BUFFER *bufs,
494     size_t *wpinited);
495 int tls1_allocate_write_buffers(OSSL_RECORD_LAYER *rl,
496     OSSL_RECORD_TEMPLATE *templates,
497     size_t numtempl, size_t *prefix);
498 int tls1_initialise_write_packets(OSSL_RECORD_LAYER *rl,
499     OSSL_RECORD_TEMPLATE *templates,
500     size_t numtempl,
501     OSSL_RECORD_TEMPLATE *prefixtempl,
502     WPACKET *pkt,
503     TLS_BUFFER *bufs,
504     size_t *wpinited);
505 int tls_prepare_record_header_default(OSSL_RECORD_LAYER *rl,
506     WPACKET *thispkt,
507     OSSL_RECORD_TEMPLATE *templ,
508     uint8_t rectype,
509     unsigned char **recdata);
510 int tls_prepare_for_encryption_default(OSSL_RECORD_LAYER *rl,
511     size_t mac_size,
512     WPACKET *thispkt,
513     TLS_RL_RECORD *thiswr);
514 int tls_post_encryption_processing_default(OSSL_RECORD_LAYER *rl,
515     size_t mac_size,
516     OSSL_RECORD_TEMPLATE *thistempl,
517     WPACKET *thispkt,
518     TLS_RL_RECORD *thiswr);
519 int tls_write_records_default(OSSL_RECORD_LAYER *rl,
520     OSSL_RECORD_TEMPLATE *templates,
521     size_t numtempl);
522 
523 /* Macros/functions provided by the TLS_BUFFER component */
524 
525 #define TLS_BUFFER_get_buf(b) ((b)->buf)
526 #define TLS_BUFFER_set_buf(b, n) ((b)->buf = (n))
527 #define TLS_BUFFER_get_len(b) ((b)->len)
528 #define TLS_BUFFER_get_left(b) ((b)->left)
529 #define TLS_BUFFER_set_left(b, l) ((b)->left = (l))
530 #define TLS_BUFFER_sub_left(b, l) ((b)->left -= (l))
531 #define TLS_BUFFER_get_offset(b) ((b)->offset)
532 #define TLS_BUFFER_set_offset(b, o) ((b)->offset = (o))
533 #define TLS_BUFFER_add_offset(b, o) ((b)->offset += (o))
534 #define TLS_BUFFER_set_app_buffer(b, l) ((b)->app_buffer = (l))
535 #define TLS_BUFFER_is_app_buffer(b) ((b)->app_buffer)
536 
537 void ossl_tls_buffer_release(TLS_BUFFER *b);
538