Coverage Report

Created: 2025-07-01 07:00

/src/openssh/sshbuf-getput-basic.c
Line
Count
Source (jump to first uncovered line)
1
/*  $OpenBSD: sshbuf-getput-basic.c,v 1.13 2022/05/25 06:03:44 djm Exp $  */
2
/*
3
 * Copyright (c) 2011 Damien Miller
4
 *
5
 * Permission to use, copy, modify, and distribute this software for any
6
 * purpose with or without fee is hereby granted, provided that the above
7
 * copyright notice and this permission notice appear in all copies.
8
 *
9
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16
 */
17
18
#define SSHBUF_INTERNAL
19
#include "includes.h"
20
21
#include <sys/types.h>
22
23
#include <stdarg.h>
24
#include <stdlib.h>
25
#include <stdio.h>
26
#include <string.h>
27
#ifdef HAVE_STDINT_H
28
# include <stdint.h>
29
#endif
30
31
#include "ssherr.h"
32
#include "sshbuf.h"
33
34
int
35
sshbuf_get(struct sshbuf *buf, void *v, size_t len)
36
0
{
37
0
  const u_char *p = sshbuf_ptr(buf);
38
0
  int r;
39
40
0
  if ((r = sshbuf_consume(buf, len)) < 0)
41
0
    return r;
42
0
  if (v != NULL && len != 0)
43
0
    memcpy(v, p, len);
44
0
  return 0;
45
0
}
46
47
int
48
sshbuf_get_u64(struct sshbuf *buf, u_int64_t *valp)
49
6.01k
{
50
6.01k
  const u_char *p = sshbuf_ptr(buf);
51
6.01k
  int r;
52
53
6.01k
  if ((r = sshbuf_consume(buf, 8)) < 0)
54
49
    return r;
55
5.96k
  if (valp != NULL)
56
5.96k
    *valp = PEEK_U64(p);
57
5.96k
  return 0;
58
6.01k
}
59
60
int
61
sshbuf_get_u32(struct sshbuf *buf, u_int32_t *valp)
62
2.41k
{
63
2.41k
  const u_char *p = sshbuf_ptr(buf);
64
2.41k
  int r;
65
66
2.41k
  if ((r = sshbuf_consume(buf, 4)) < 0)
67
9
    return r;
68
2.40k
  if (valp != NULL)
69
2.40k
    *valp = PEEK_U32(p);
70
2.40k
  return 0;
71
2.41k
}
72
73
int
74
sshbuf_get_u16(struct sshbuf *buf, u_int16_t *valp)
75
0
{
76
0
  const u_char *p = sshbuf_ptr(buf);
77
0
  int r;
78
79
0
  if ((r = sshbuf_consume(buf, 2)) < 0)
80
0
    return r;
81
0
  if (valp != NULL)
82
0
    *valp = PEEK_U16(p);
83
0
  return 0;
84
0
}
85
86
int
87
sshbuf_get_u8(struct sshbuf *buf, u_char *valp)
88
367
{
89
367
  const u_char *p = sshbuf_ptr(buf);
90
367
  int r;
91
92
367
  if ((r = sshbuf_consume(buf, 1)) < 0)
93
2
    return r;
94
365
  if (valp != NULL)
95
365
    *valp = (u_int8_t)*p;
96
365
  return 0;
97
367
}
98
99
static int
100
check_offset(const struct sshbuf *buf, int wr, size_t offset, size_t len)
101
0
{
102
0
  if (sshbuf_ptr(buf) == NULL) /* calls sshbuf_check_sanity() */
103
0
    return SSH_ERR_INTERNAL_ERROR;
104
0
  if (offset >= SIZE_MAX - len)
105
0
    return SSH_ERR_INVALID_ARGUMENT;
106
0
  if (offset + len > sshbuf_len(buf)) {
107
0
    return wr ?
108
0
        SSH_ERR_NO_BUFFER_SPACE : SSH_ERR_MESSAGE_INCOMPLETE;
109
0
  }
110
0
  return 0;
111
0
}
112
113
static int
114
check_roffset(const struct sshbuf *buf, size_t offset, size_t len,
115
    const u_char **p)
116
0
{
117
0
  int r;
118
119
0
  *p = NULL;
120
0
  if ((r = check_offset(buf, 0, offset, len)) != 0)
121
0
    return r;
122
0
  *p = sshbuf_ptr(buf) + offset;
123
0
  return 0;
124
0
}
125
126
int
127
sshbuf_peek_u64(const struct sshbuf *buf, size_t offset, u_int64_t *valp)
128
0
{
129
0
  const u_char *p = NULL;
130
0
  int r;
131
132
0
  if (valp != NULL)
133
0
    *valp = 0;
134
0
  if ((r = check_roffset(buf, offset, 8, &p)) != 0)
135
0
    return r;
136
0
  if (valp != NULL)
137
0
    *valp = PEEK_U64(p);
138
0
  return 0;
139
0
}
140
141
int
142
sshbuf_peek_u32(const struct sshbuf *buf, size_t offset, u_int32_t *valp)
143
0
{
144
0
  const u_char *p = NULL;
145
0
  int r;
146
147
0
  if (valp != NULL)
148
0
    *valp = 0;
149
0
  if ((r = check_roffset(buf, offset, 4, &p)) != 0)
150
0
    return r;
151
0
  if (valp != NULL)
152
0
    *valp = PEEK_U32(p);
153
0
  return 0;
154
0
}
155
156
int
157
sshbuf_peek_u16(const struct sshbuf *buf, size_t offset, u_int16_t *valp)
158
0
{
159
0
  const u_char *p = NULL;
160
0
  int r;
161
162
0
  if (valp != NULL)
163
0
    *valp = 0;
164
0
  if ((r = check_roffset(buf, offset, 2, &p)) != 0)
165
0
    return r;
166
0
  if (valp != NULL)
167
0
    *valp = PEEK_U16(p);
168
0
  return 0;
169
0
}
170
171
int
172
sshbuf_peek_u8(const struct sshbuf *buf, size_t offset, u_char *valp)
173
0
{
174
0
  const u_char *p = NULL;
175
0
  int r;
176
177
0
  if (valp != NULL)
178
0
    *valp = 0;
179
0
  if ((r = check_roffset(buf, offset, 1, &p)) != 0)
180
0
    return r;
181
0
  if (valp != NULL)
182
0
    *valp = *p;
183
0
  return 0;
184
0
}
185
186
int
187
sshbuf_get_string(struct sshbuf *buf, u_char **valp, size_t *lenp)
188
4.77k
{
189
4.77k
  const u_char *val;
190
4.77k
  size_t len;
191
4.77k
  int r;
192
193
4.77k
  if (valp != NULL)
194
4.77k
    *valp = NULL;
195
4.77k
  if (lenp != NULL)
196
4.77k
    *lenp = 0;
197
4.77k
  if ((r = sshbuf_get_string_direct(buf, &val, &len)) < 0)
198
96
    return r;
199
4.68k
  if (valp != NULL) {
200
4.68k
    if ((*valp = malloc(len + 1)) == NULL) {
201
0
      SSHBUF_DBG(("SSH_ERR_ALLOC_FAIL"));
202
0
      return SSH_ERR_ALLOC_FAIL;
203
0
    }
204
4.68k
    if (len != 0)
205
4.34k
      memcpy(*valp, val, len);
206
4.68k
    (*valp)[len] = '\0';
207
4.68k
  }
208
4.68k
  if (lenp != NULL)
209
4.68k
    *lenp = len;
210
4.68k
  return 0;
211
4.68k
}
212
213
int
214
sshbuf_get_string_direct(struct sshbuf *buf, const u_char **valp, size_t *lenp)
215
28.0k
{
216
28.0k
  size_t len;
217
28.0k
  const u_char *p;
218
28.0k
  int r;
219
220
28.0k
  if (valp != NULL)
221
5.37k
    *valp = NULL;
222
28.0k
  if (lenp != NULL)
223
5.37k
    *lenp = 0;
224
28.0k
  if ((r = sshbuf_peek_string_direct(buf, &p, &len)) < 0)
225
281
    return r;
226
27.7k
  if (valp != NULL)
227
5.26k
    *valp = p;
228
27.7k
  if (lenp != NULL)
229
5.26k
    *lenp = len;
230
27.7k
  if (sshbuf_consume(buf, len + 4) != 0) {
231
    /* Shouldn't happen */
232
0
    SSHBUF_DBG(("SSH_ERR_INTERNAL_ERROR"));
233
0
    SSHBUF_ABORT();
234
0
    return SSH_ERR_INTERNAL_ERROR;
235
0
  }
236
27.7k
  return 0;
237
27.7k
}
238
239
int
240
sshbuf_peek_string_direct(const struct sshbuf *buf, const u_char **valp,
241
    size_t *lenp)
242
53.7k
{
243
53.7k
  u_int32_t len;
244
53.7k
  const u_char *p = sshbuf_ptr(buf);
245
246
53.7k
  if (valp != NULL)
247
53.7k
    *valp = NULL;
248
53.7k
  if (lenp != NULL)
249
53.7k
    *lenp = 0;
250
53.7k
  if (sshbuf_len(buf) < 4) {
251
297
    SSHBUF_DBG(("SSH_ERR_MESSAGE_INCOMPLETE"));
252
297
    return SSH_ERR_MESSAGE_INCOMPLETE;
253
297
  }
254
53.4k
  len = PEEK_U32(p);
255
53.4k
  if (len > SSHBUF_SIZE_MAX - 4) {
256
300
    SSHBUF_DBG(("SSH_ERR_STRING_TOO_LARGE"));
257
300
    return SSH_ERR_STRING_TOO_LARGE;
258
300
  }
259
53.1k
  if (sshbuf_len(buf) - 4 < len) {
260
351
    SSHBUF_DBG(("SSH_ERR_MESSAGE_INCOMPLETE"));
261
351
    return SSH_ERR_MESSAGE_INCOMPLETE;
262
351
  }
263
52.8k
  if (valp != NULL)
264
52.8k
    *valp = p + 4;
265
52.8k
  if (lenp != NULL)
266
52.8k
    *lenp = len;
267
52.8k
  return 0;
268
53.1k
}
269
270
int
271
sshbuf_get_cstring(struct sshbuf *buf, char **valp, size_t *lenp)
272
14.9k
{
273
14.9k
  size_t len;
274
14.9k
  const u_char *p, *z;
275
14.9k
  int r;
276
277
14.9k
  if (valp != NULL)
278
14.9k
    *valp = NULL;
279
14.9k
  if (lenp != NULL)
280
2.05k
    *lenp = 0;
281
14.9k
  if ((r = sshbuf_peek_string_direct(buf, &p, &len)) != 0)
282
343
    return r;
283
  /* Allow a \0 only at the end of the string */
284
14.6k
  if (len > 0 &&
285
14.6k
      (z = memchr(p , '\0', len)) != NULL && z < p + len - 1) {
286
12
    SSHBUF_DBG(("SSH_ERR_INVALID_FORMAT"));
287
12
    return SSH_ERR_INVALID_FORMAT;
288
12
  }
289
14.6k
  if ((r = sshbuf_skip_string(buf)) != 0)
290
0
    return -1;
291
14.6k
  if (valp != NULL) {
292
14.6k
    if ((*valp = malloc(len + 1)) == NULL) {
293
0
      SSHBUF_DBG(("SSH_ERR_ALLOC_FAIL"));
294
0
      return SSH_ERR_ALLOC_FAIL;
295
0
    }
296
14.6k
    if (len != 0)
297
8.00k
      memcpy(*valp, p, len);
298
14.6k
    (*valp)[len] = '\0';
299
14.6k
  }
300
14.6k
  if (lenp != NULL)
301
2.04k
    *lenp = (size_t)len;
302
14.6k
  return 0;
303
14.6k
}
304
305
int
306
sshbuf_get_stringb(struct sshbuf *buf, struct sshbuf *v)
307
0
{
308
0
  u_int32_t len;
309
0
  u_char *p;
310
0
  int r;
311
312
  /*
313
   * Use sshbuf_peek_string_direct() to figure out if there is
314
   * a complete string in 'buf' and copy the string directly
315
   * into 'v'.
316
   */
317
0
  if ((r = sshbuf_peek_string_direct(buf, NULL, NULL)) != 0 ||
318
0
      (r = sshbuf_get_u32(buf, &len)) != 0 ||
319
0
      (r = sshbuf_reserve(v, len, &p)) != 0 ||
320
0
      (r = sshbuf_get(buf, p, len)) != 0)
321
0
    return r;
322
0
  return 0;
323
0
}
324
325
int
326
sshbuf_put(struct sshbuf *buf, const void *v, size_t len)
327
6.39k
{
328
6.39k
  u_char *p;
329
6.39k
  int r;
330
331
6.39k
  if ((r = sshbuf_reserve(buf, len, &p)) < 0)
332
0
    return r;
333
6.39k
  if (len != 0)
334
2.88k
    memcpy(p, v, len);
335
6.39k
  return 0;
336
6.39k
}
337
338
int
339
sshbuf_putb(struct sshbuf *buf, const struct sshbuf *v)
340
5.78k
{
341
5.78k
  if (v == NULL)
342
9
    return 0;
343
5.77k
  return sshbuf_put(buf, sshbuf_ptr(v), sshbuf_len(v));
344
5.78k
}
345
346
int
347
sshbuf_putf(struct sshbuf *buf, const char *fmt, ...)
348
0
{
349
0
  va_list ap;
350
0
  int r;
351
352
0
  va_start(ap, fmt);
353
0
  r = sshbuf_putfv(buf, fmt, ap);
354
0
  va_end(ap);
355
0
  return r;
356
0
}
357
358
int
359
sshbuf_putfv(struct sshbuf *buf, const char *fmt, va_list ap)
360
0
{
361
0
  va_list ap2;
362
0
  int r, len;
363
0
  u_char *p;
364
365
0
  VA_COPY(ap2, ap);
366
0
  if ((len = vsnprintf(NULL, 0, fmt, ap2)) < 0) {
367
0
    r = SSH_ERR_INVALID_ARGUMENT;
368
0
    goto out;
369
0
  }
370
0
  if (len == 0) {
371
0
    r = 0;
372
0
    goto out; /* Nothing to do */
373
0
  }
374
0
  va_end(ap2);
375
0
  VA_COPY(ap2, ap);
376
0
  if ((r = sshbuf_reserve(buf, (size_t)len + 1, &p)) < 0)
377
0
    goto out;
378
0
  if ((r = vsnprintf((char *)p, len + 1, fmt, ap2)) != len) {
379
0
    r = SSH_ERR_INTERNAL_ERROR;
380
0
    goto out; /* Shouldn't happen */
381
0
  }
382
  /* Consume terminating \0 */
383
0
  if ((r = sshbuf_consume_end(buf, 1)) != 0)
384
0
    goto out;
385
0
  r = 0;
386
0
 out:
387
0
  va_end(ap2);
388
0
  return r;
389
0
}
390
391
int
392
sshbuf_put_u64(struct sshbuf *buf, u_int64_t val)
393
0
{
394
0
  u_char *p;
395
0
  int r;
396
397
0
  if ((r = sshbuf_reserve(buf, 8, &p)) < 0)
398
0
    return r;
399
0
  POKE_U64(p, val);
400
0
  return 0;
401
0
}
402
403
int
404
sshbuf_put_u32(struct sshbuf *buf, u_int32_t val)
405
25
{
406
25
  u_char *p;
407
25
  int r;
408
409
25
  if ((r = sshbuf_reserve(buf, 4, &p)) < 0)
410
0
    return r;
411
25
  POKE_U32(p, val);
412
25
  return 0;
413
25
}
414
415
int
416
sshbuf_put_u16(struct sshbuf *buf, u_int16_t val)
417
0
{
418
0
  u_char *p;
419
0
  int r;
420
421
0
  if ((r = sshbuf_reserve(buf, 2, &p)) < 0)
422
0
    return r;
423
0
  POKE_U16(p, val);
424
0
  return 0;
425
0
}
426
427
int
428
sshbuf_put_u8(struct sshbuf *buf, u_char val)
429
25
{
430
25
  u_char *p;
431
25
  int r;
432
433
25
  if ((r = sshbuf_reserve(buf, 1, &p)) < 0)
434
0
    return r;
435
25
  p[0] = val;
436
25
  return 0;
437
25
}
438
439
static int
440
check_woffset(struct sshbuf *buf, size_t offset, size_t len, u_char **p)
441
0
{
442
0
  int r;
443
444
0
  *p = NULL;
445
0
  if ((r = check_offset(buf, 1, offset, len)) != 0)
446
0
    return r;
447
0
  if (sshbuf_mutable_ptr(buf) == NULL)
448
0
    return SSH_ERR_BUFFER_READ_ONLY;
449
0
  *p = sshbuf_mutable_ptr(buf) + offset;
450
0
  return 0;
451
0
}
452
453
int
454
sshbuf_poke_u64(struct sshbuf *buf, size_t offset, u_int64_t val)
455
0
{
456
0
  u_char *p = NULL;
457
0
  int r;
458
459
0
  if ((r = check_woffset(buf, offset, 8, &p)) != 0)
460
0
    return r;
461
0
  POKE_U64(p, val);
462
0
  return 0;
463
0
}
464
465
int
466
sshbuf_poke_u32(struct sshbuf *buf, size_t offset, u_int32_t val)
467
0
{
468
0
  u_char *p = NULL;
469
0
  int r;
470
471
0
  if ((r = check_woffset(buf, offset, 4, &p)) != 0)
472
0
    return r;
473
0
  POKE_U32(p, val);
474
0
  return 0;
475
0
}
476
477
int
478
sshbuf_poke_u16(struct sshbuf *buf, size_t offset, u_int16_t val)
479
0
{
480
0
  u_char *p = NULL;
481
0
  int r;
482
483
0
  if ((r = check_woffset(buf, offset, 2, &p)) != 0)
484
0
    return r;
485
0
  POKE_U16(p, val);
486
0
  return 0;
487
0
}
488
489
int
490
sshbuf_poke_u8(struct sshbuf *buf, size_t offset, u_char val)
491
0
{
492
0
  u_char *p = NULL;
493
0
  int r;
494
495
0
  if ((r = check_woffset(buf, offset, 1, &p)) != 0)
496
0
    return r;
497
0
  *p = val;
498
0
  return 0;
499
0
}
500
501
int
502
sshbuf_poke(struct sshbuf *buf, size_t offset, void *v, size_t len)
503
0
{
504
0
  u_char *p = NULL;
505
0
  int r;
506
507
0
  if ((r = check_woffset(buf, offset, len, &p)) != 0)
508
0
    return r;
509
0
  memcpy(p, v, len);
510
0
  return 0;
511
0
}
512
513
int
514
sshbuf_put_string(struct sshbuf *buf, const void *v, size_t len)
515
0
{
516
0
  u_char *d;
517
0
  int r;
518
519
0
  if (len > SSHBUF_SIZE_MAX - 4) {
520
0
    SSHBUF_DBG(("SSH_ERR_NO_BUFFER_SPACE"));
521
0
    return SSH_ERR_NO_BUFFER_SPACE;
522
0
  }
523
0
  if ((r = sshbuf_reserve(buf, len + 4, &d)) < 0)
524
0
    return r;
525
0
  POKE_U32(d, len);
526
0
  if (len != 0)
527
0
    memcpy(d + 4, v, len);
528
0
  return 0;
529
0
}
530
531
int
532
sshbuf_put_cstring(struct sshbuf *buf, const char *v)
533
0
{
534
0
  return sshbuf_put_string(buf, v, v == NULL ? 0 : strlen(v));
535
0
}
536
537
int
538
sshbuf_put_stringb(struct sshbuf *buf, const struct sshbuf *v)
539
0
{
540
0
  if (v == NULL)
541
0
    return sshbuf_put_string(buf, NULL, 0);
542
543
0
  return sshbuf_put_string(buf, sshbuf_ptr(v), sshbuf_len(v));
544
0
}
545
546
int
547
sshbuf_froms(struct sshbuf *buf, struct sshbuf **bufp)
548
8.45k
{
549
8.45k
  const u_char *p;
550
8.45k
  size_t len;
551
8.45k
  struct sshbuf *ret;
552
8.45k
  int r;
553
554
8.45k
  if (buf == NULL || bufp == NULL)
555
0
    return SSH_ERR_INVALID_ARGUMENT;
556
8.45k
  *bufp = NULL;
557
8.45k
  if ((r = sshbuf_peek_string_direct(buf, &p, &len)) != 0)
558
94
    return r;
559
8.36k
  if ((ret = sshbuf_from(p, len)) == NULL)
560
0
    return SSH_ERR_ALLOC_FAIL;
561
8.36k
  if ((r = sshbuf_consume(buf, len + 4)) != 0 ||  /* Shouldn't happen */
562
8.36k
      (r = sshbuf_set_parent(ret, buf)) != 0) {
563
0
    sshbuf_free(ret);
564
0
    return r;
565
0
  }
566
8.36k
  *bufp = ret;
567
8.36k
  return 0;
568
8.36k
}
569
570
int
571
sshbuf_put_bignum2_bytes(struct sshbuf *buf, const void *v, size_t len)
572
0
{
573
0
  u_char *d;
574
0
  const u_char *s = (const u_char *)v;
575
0
  int r, prepend;
576
577
0
  if (len > SSHBUF_SIZE_MAX - 5) {
578
0
    SSHBUF_DBG(("SSH_ERR_NO_BUFFER_SPACE"));
579
0
    return SSH_ERR_NO_BUFFER_SPACE;
580
0
  }
581
  /* Skip leading zero bytes */
582
0
  for (; len > 0 && *s == 0; len--, s++)
583
0
    ;
584
  /*
585
   * If most significant bit is set then prepend a zero byte to
586
   * avoid interpretation as a negative number.
587
   */
588
0
  prepend = len > 0 && (s[0] & 0x80) != 0;
589
0
  if ((r = sshbuf_reserve(buf, len + 4 + prepend, &d)) < 0)
590
0
    return r;
591
0
  POKE_U32(d, len + prepend);
592
0
  if (prepend)
593
0
    d[4] = 0;
594
0
  if (len != 0)
595
0
    memcpy(d + 4 + prepend, s, len);
596
0
  return 0;
597
0
}
598
599
int
600
sshbuf_get_bignum2_bytes_direct(struct sshbuf *buf,
601
    const u_char **valp, size_t *lenp)
602
1.47k
{
603
1.47k
  const u_char *d;
604
1.47k
  size_t len, olen;
605
1.47k
  int r;
606
607
1.47k
  if ((r = sshbuf_peek_string_direct(buf, &d, &olen)) < 0)
608
158
    return r;
609
1.31k
  len = olen;
610
  /* Refuse negative (MSB set) bignums */
611
1.31k
  if ((len != 0 && (*d & 0x80) != 0))
612
16
    return SSH_ERR_BIGNUM_IS_NEGATIVE;
613
  /* Refuse overlong bignums, allow prepended \0 to avoid MSB set */
614
1.30k
  if (len > SSHBUF_MAX_BIGNUM + 1 ||
615
1.30k
      (len == SSHBUF_MAX_BIGNUM + 1 && *d != 0))
616
16
    return SSH_ERR_BIGNUM_TOO_LARGE;
617
  /* Trim leading zeros */
618
2.52k
  while (len > 0 && *d == 0x00) {
619
1.24k
    d++;
620
1.24k
    len--;
621
1.24k
  }
622
1.28k
  if (valp != NULL)
623
1.28k
    *valp = d;
624
1.28k
  if (lenp != NULL)
625
1.28k
    *lenp = len;
626
1.28k
  if (sshbuf_consume(buf, olen + 4) != 0) {
627
    /* Shouldn't happen */
628
0
    SSHBUF_DBG(("SSH_ERR_INTERNAL_ERROR"));
629
0
    SSHBUF_ABORT();
630
0
    return SSH_ERR_INTERNAL_ERROR;
631
0
  }
632
1.28k
  return 0;
633
1.28k
}