Bug Summary

File:epan/tvbuff.c
Warning:line 491, column 10
Potential leak of memory pointed to by 'buf'

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name tvbuff.c -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 2 -fhalf-no-semantic-interposition -fno-delete-null-pointer-checks -mframe-pointer=all -relaxed-aliasing -fmath-errno -ffp-contract=on -fno-rounding-math -ffloat16-excess-precision=fast -fbfloat16-excess-precision=fast -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/builds/wireshark/wireshark/build -fcoverage-compilation-dir=/builds/wireshark/wireshark/build -resource-dir /usr/lib/llvm-20/lib/clang/20 -isystem /usr/include/glib-2.0 -isystem /usr/lib/x86_64-linux-gnu/glib-2.0/include -isystem /builds/wireshark/wireshark/epan -isystem /builds/wireshark/wireshark/build/epan -isystem /usr/include/mit-krb5 -isystem /usr/include/libxml2 -isystem /usr/include/lua5.4 -D G_DISABLE_DEPRECATED -D G_DISABLE_SINGLE_INCLUDES -D WS_BUILD_DLL -D WS_DEBUG -D WS_DEBUG_UTF_8 -D epan_EXPORTS -I /builds/wireshark/wireshark/build -I /builds/wireshark/wireshark -I /builds/wireshark/wireshark/include -I /builds/wireshark/wireshark/wiretap -D _GLIBCXX_ASSERTIONS -internal-isystem /usr/lib/llvm-20/lib/clang/20/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fmacro-prefix-map=/builds/wireshark/wireshark/= -fmacro-prefix-map=/builds/wireshark/wireshark/build/= -fmacro-prefix-map=../= -Wno-format-truncation -Wno-format-nonliteral -Wno-pointer-sign -std=gnu11 -ferror-limit 19 -fvisibility=hidden -fwrapv -fwrapv-pointer -fstrict-flex-arrays=3 -stack-protector 2 -fstack-clash-protection -fcf-protection=full -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fexceptions -fcolor-diagnostics -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /builds/wireshark/wireshark/sbout/2025-09-10-100354-3933-1 -x c /builds/wireshark/wireshark/epan/tvbuff.c
1/* tvbuff.c
2 *
3 * Testy, Virtual(-izable) Buffer of uint8_t*'s
4 *
5 * "Testy" -- the buffer gets mad when an attempt to access data
6 * beyond the bounds of the buffer. An exception is thrown.
7 *
8 * "Virtual" -- the buffer can have its own data, can use a subset of
9 * the data of a backing tvbuff, or can be a composite of
10 * other tvbuffs.
11 *
12 * Copyright (c) 2000 by Gilbert Ramirez <[email protected]>
13 *
14 * Code to convert IEEE floating point formats to native floating point
15 * derived from code Copyright (c) Ashok Narayanan, 2000
16 *
17 * Wireshark - Network traffic analyzer
18 * By Gerald Combs <[email protected]>
19 * Copyright 1998 Gerald Combs
20 *
21 * SPDX-License-Identifier: GPL-2.0-or-later
22 */
23
24#include "config.h"
25
26#include <string.h>
27#include <stdio.h>
28#include <errno(*__errno_location ()).h>
29
30#include <glib.h>
31
32#include "wsutil/pint.h"
33#include "wsutil/sign_ext.h"
34#include "wsutil/strtoi.h"
35#include "wsutil/unicode-utils.h"
36#include "wsutil/nstime.h"
37#include "wsutil/time_util.h"
38#include <wsutil/ws_assert.h>
39#include "tvbuff.h"
40#include "tvbuff-int.h"
41#include "strutil.h"
42#include "to_str.h"
43#include "charsets.h"
44#include "proto.h" /* XXX - only used for DISSECTOR_ASSERT, probably a new header file? */
45#include "exceptions.h"
46
47#include <time.h>
48
49static uint64_t
50_tvb_get_bits64(tvbuff_t *tvb, unsigned bit_offset, const int total_no_of_bits);
51
52static uint64_t
53_tvb_get_bits64_le(tvbuff_t *tvb, unsigned bit_offset, const int total_no_of_bits);
54
55static inline int
56_tvb_captured_length_remaining(const tvbuff_t *tvb, const int offset);
57
58static inline const uint8_t*
59ensure_contiguous(tvbuff_t *tvb, const int offset, const int length);
60
61static inline uint8_t *
62tvb_get_raw_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, const int length);
63
64tvbuff_t *
65tvb_new(const struct tvb_ops *ops)
66{
67 tvbuff_t *tvb;
68 size_t size = ops->tvb_size;
69
70 ws_assert(size >= sizeof(*tvb))do { if ((1) && !(size >= sizeof(*tvb))) ws_log_fatal_full
("", LOG_LEVEL_ERROR, "epan/tvbuff.c", 70, __func__, "assertion failed: %s"
, "size >= sizeof(*tvb)"); } while (0)
;
71
72 tvb = (tvbuff_t *) g_slice_alloc(size);
73
74 tvb->next = NULL((void*)0);
75 tvb->ops = ops;
76 tvb->initialized = false0;
77 tvb->flags = 0;
78 tvb->length = 0;
79 tvb->reported_length = 0;
80 tvb->contained_length = 0;
81 tvb->real_data = NULL((void*)0);
82 tvb->raw_offset = -1;
83 tvb->ds_tvb = NULL((void*)0);
84
85 return tvb;
86}
87
88static void
89tvb_free_internal(tvbuff_t *tvb)
90{
91 size_t size;
92
93 DISSECTOR_ASSERT(tvb)((void) ((tvb) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/tvbuff.c", 93, "tvb"))))
;
94
95 if (tvb->ops->tvb_free)
96 tvb->ops->tvb_free(tvb);
97
98 size = tvb->ops->tvb_size;
99
100 g_slice_free1(size, tvb);
101}
102
103/* XXX: just call tvb_free_chain();
104 * Not removed so that existing dissectors using tvb_free() need not be changed.
105 * I'd argue that existing calls to tvb_free() should have actually beeen
106 * calls to tvb_free_chain() although the calls were OK as long as no
107 * subsets, etc had been created on the tvb. */
108void
109tvb_free(tvbuff_t *tvb)
110{
111 tvb_free_chain(tvb);
112}
113
114void
115tvb_free_chain(tvbuff_t *tvb)
116{
117 tvbuff_t *next_tvb;
118 DISSECTOR_ASSERT(tvb)((void) ((tvb) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/tvbuff.c", 118, "tvb"))))
;
119 while (tvb) {
120 next_tvb = tvb->next;
121 tvb_free_internal(tvb);
122 tvb = next_tvb;
123 }
124}
125
126tvbuff_t *
127tvb_new_chain(tvbuff_t *parent, tvbuff_t *backing)
128{
129 tvbuff_t *tvb = tvb_new_proxy(backing);
130
131 tvb_add_to_chain(parent, tvb);
132 return tvb;
133}
134
135void
136tvb_add_to_chain(tvbuff_t *parent, tvbuff_t *child)
137{
138 tvbuff_t *tmp;
139
140 DISSECTOR_ASSERT(parent)((void) ((parent) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/tvbuff.c", 140, "parent"))))
;
141 DISSECTOR_ASSERT(child)((void) ((child) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/tvbuff.c", 141, "child"))))
;
142
143 while (child) {
144 tmp = child;
145 child = child->next;
146
147 tmp->next = parent->next;
148 parent->next = tmp;
149 }
150}
151
152/*
153 * Check whether that offset goes more than one byte past the
154 * end of the buffer.
155 *
156 * If not, return 0; otherwise, return exception
157 */
158static inline int
159validate_offset(const tvbuff_t *tvb, const unsigned abs_offset)
160{
161 if (G_LIKELY(abs_offset <= tvb->length)(abs_offset <= tvb->length)) {
162 /* It's OK. */
163 return 0;
164 }
165
166 /*
167 * It's not OK, but why? Which boundaries is it
168 * past?
169 */
170 if (abs_offset <= tvb->contained_length) {
171 /*
172 * It's past the captured length, but not past
173 * the reported end of any parent tvbuffs from
174 * which this is constructed, or the reported
175 * end of this tvbuff, so it's out of bounds
176 * solely because we're past the end of the
177 * captured data.
178 */
179 return BoundsError1;
180 }
181
182 /*
183 * There's some actual packet boundary, not just the
184 * artificial boundary imposed by packet slicing, that
185 * we're past.
186 */
187
188 if (tvb->flags & TVBUFF_FRAGMENT0x00000001) {
189 /*
190 * This tvbuff is the first fragment of a larger
191 * packet that hasn't been reassembled, so we
192 * assume that's the source of the problem - if
193 * we'd reassembled the packet, we wouldn't have
194 * gone past the end.
195 *
196 * That might not be true, but for at least
197 * some forms of reassembly, such as IP
198 * reassembly, you don't know how big the
199 * reassembled packet is unless you reassemble
200 * it, so, in those cases, we can't determine
201 * whether we would have gone past the end
202 * had we reassembled the packet.
203 */
204 return FragmentBoundsError4;
205 }
206
207 /* OK, we're not an unreassembled fragment (that we know of). */
208 if (abs_offset <= tvb->reported_length) {
209 /*
210 * We're within the bounds of what this tvbuff
211 * purportedly contains, based on some length
212 * value, but we're not within the bounds of
213 * something from which this tvbuff was
214 * extracted, so that length value ran past
215 * the end of some parent tvbuff.
216 */
217 return ContainedBoundsError2;
218 }
219
220 /*
221 * OK, it looks as if we ran past the claimed length
222 * of data.
223 */
224 return ReportedBoundsError3;
225}
226
227static inline int
228compute_offset(const tvbuff_t *tvb, const int offset, unsigned *offset_ptr)
229{
230 if (offset >= 0) {
231 /* Positive offset - relative to the beginning of the packet. */
232 if (G_LIKELY((unsigned) offset <= tvb->length)((unsigned) offset <= tvb->length)) {
233 *offset_ptr = offset;
234 } else if ((unsigned) offset <= tvb->contained_length) {
235 return BoundsError1;
236 } else if (tvb->flags & TVBUFF_FRAGMENT0x00000001) {
237 return FragmentBoundsError4;
238 } else if ((unsigned) offset <= tvb->reported_length) {
239 return ContainedBoundsError2;
240 } else {
241 return ReportedBoundsError3;
242 }
243 }
244 else {
245 /* Negative offset - relative to the end of the packet. */
246 if (G_LIKELY((unsigned) -offset <= tvb->length)((unsigned) -offset <= tvb->length)) {
247 *offset_ptr = tvb->length + offset;
248 } else if ((unsigned) -offset <= tvb->contained_length) {
249 return BoundsError1;
250 } else if (tvb->flags & TVBUFF_FRAGMENT0x00000001) {
251 return FragmentBoundsError4;
252 } else if ((unsigned) -offset <= tvb->reported_length) {
253 return ContainedBoundsError2;
254 } else {
255 return ReportedBoundsError3;
256 }
257 }
258
259 return 0;
260}
261
262static inline int
263compute_offset_and_remaining(const tvbuff_t *tvb, const int offset, unsigned *offset_ptr, unsigned *rem_len)
264{
265 int exception;
266
267 exception = compute_offset(tvb, offset, offset_ptr);
268 if (!exception)
269 *rem_len = tvb->length - *offset_ptr;
270
271 return exception;
272}
273
274/* Computes the absolute offset and length based on a possibly-negative offset
275 * and a length that is possible -1 (which means "to the end of the data").
276 * Returns integer indicating whether the offset is in bounds (0) or
277 * not (exception number). The integer ptrs are modified with the new offset,
278 * captured (available) length, and contained length (amount that's present
279 * in the parent tvbuff based on its reported length).
280 * No exception is thrown; on success, we return 0, otherwise we return an
281 * exception for the caller to throw if appropriate.
282 *
283 * XXX - we return success (0), if the offset is positive and right
284 * after the end of the tvbuff (i.e., equal to the length). We do this
285 * so that a dissector constructing a subset tvbuff for the next protocol
286 * will get a zero-length tvbuff, not an exception, if there's no data
287 * left for the next protocol - we want the next protocol to be the one
288 * that gets an exception, so the error is reported as an error in that
289 * protocol rather than the containing protocol. */
290static inline int
291check_offset_length_no_exception(const tvbuff_t *tvb,
292 const int offset, int const length_val,
293 unsigned *offset_ptr, unsigned *length_ptr)
294{
295 unsigned end_offset;
296 int exception;
297
298 DISSECTOR_ASSERT(offset_ptr)((void) ((offset_ptr) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 298, "offset_ptr"
))))
;
299 DISSECTOR_ASSERT(length_ptr)((void) ((length_ptr) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 299, "length_ptr"
))))
;
300
301 /* Compute the offset */
302 exception = compute_offset(tvb, offset, offset_ptr);
303 if (exception)
304 return exception;
305
306 if (length_val < -1) {
307 /* XXX - ReportedBoundsError? */
308 return BoundsError1;
309 }
310
311 /* Compute the length */
312 if (length_val == -1)
313 *length_ptr = tvb->length - *offset_ptr;
314 else
315 *length_ptr = length_val;
316
317 /*
318 * Compute the offset of the first byte past the length.
319 */
320 end_offset = *offset_ptr + *length_ptr;
321
322 /*
323 * Check for an overflow
324 */
325 if (end_offset < *offset_ptr)
326 return BoundsError1;
327
328 return validate_offset(tvb, end_offset);
329}
330
331/* Checks (+/-) offset and length and throws an exception if
332 * either is out of bounds. Sets integer ptrs to the new offset
333 * and length. */
334static inline void
335check_offset_length(const tvbuff_t *tvb,
336 const int offset, int const length_val,
337 unsigned *offset_ptr, unsigned *length_ptr)
338{
339 int exception;
340
341 exception = check_offset_length_no_exception(tvb, offset, length_val, offset_ptr, length_ptr);
342 if (exception)
343 THROW(exception)except_throw(1, (exception), ((void*)0));
344}
345
346void
347tvb_check_offset_length(const tvbuff_t *tvb,
348 const int offset, int const length_val,
349 unsigned *offset_ptr, unsigned *length_ptr)
350{
351 check_offset_length(tvb, offset, length_val, offset_ptr, length_ptr);
352}
353
354static const unsigned char left_aligned_bitmask[] = {
355 0xff,
356 0x80,
357 0xc0,
358 0xe0,
359 0xf0,
360 0xf8,
361 0xfc,
362 0xfe
363};
364
365tvbuff_t *
366tvb_new_octet_aligned(tvbuff_t *tvb, uint32_t bit_offset, int32_t no_of_bits)
367{
368 tvbuff_t *sub_tvb = NULL((void*)0);
369 uint32_t byte_offset;
370 int32_t datalen, i;
371 uint8_t left, right, remaining_bits, *buf;
372 const uint8_t *data;
373
374 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 374, "tvb && tvb->initialized"
))))
;
375
376 byte_offset = bit_offset >> 3;
377 left = bit_offset % 8; /* for left-shifting */
378 right = 8 - left; /* for right-shifting */
379
380 if (no_of_bits == -1) {
381 datalen = _tvb_captured_length_remaining(tvb, byte_offset);
382 remaining_bits = 0;
383 } else {
384 datalen = no_of_bits >> 3;
385 remaining_bits = no_of_bits % 8;
386 if (remaining_bits) {
387 datalen++;
388 }
389 }
390
391 /* already aligned -> shortcut */
392 if ((left == 0) && (remaining_bits == 0)) {
393 return tvb_new_subset_length_caplen(tvb, byte_offset, datalen, datalen);
394 }
395
396 DISSECTOR_ASSERT(datalen>0)((void) ((datalen>0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 396, "datalen>0"
))))
;
397
398 /* if at least one trailing byte is available, we must use the content
399 * of that byte for the last shift (i.e. tvb_get_ptr() must use datalen + 1
400 * if non extra byte is available, the last shifted byte requires
401 * special treatment
402 */
403 if (_tvb_captured_length_remaining(tvb, byte_offset) > datalen) {
404 data = ensure_contiguous(tvb, byte_offset, datalen + 1); /* tvb_get_ptr */
405
406 /* Do this allocation AFTER tvb_get_ptr() (which could throw an exception) */
407 buf = (uint8_t *)g_malloc(datalen);
408
409 /* shift tvb data bit_offset bits to the left */
410 for (i = 0; i < datalen; i++)
411 buf[i] = (data[i] << left) | (data[i+1] >> right);
412 } else {
413 data = ensure_contiguous(tvb, byte_offset, datalen); /* tvb_get_ptr() */
414
415 /* Do this allocation AFTER tvb_get_ptr() (which could throw an exception) */
416 buf = (uint8_t *)g_malloc(datalen);
417
418 /* shift tvb data bit_offset bits to the left */
419 for (i = 0; i < (datalen-1); i++)
420 buf[i] = (data[i] << left) | (data[i+1] >> right);
421 buf[datalen-1] = data[datalen-1] << left; /* set last octet */
422 }
423 buf[datalen-1] &= left_aligned_bitmask[remaining_bits];
424
425 sub_tvb = tvb_new_child_real_data(tvb, buf, datalen, datalen);
426 tvb_set_free_cb(sub_tvb, g_free);
427
428 return sub_tvb;
429}
430
431tvbuff_t *
432tvb_new_octet_right_aligned(tvbuff_t *tvb, uint32_t bit_offset, int32_t no_of_bits)
433{
434 tvbuff_t *sub_tvb = NULL((void*)0);
435 uint32_t byte_offset;
436 int src_len, dst_len, i;
437 uint8_t left, right, remaining_bits, *buf;
438 const uint8_t *data;
439
440 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 440, "tvb && tvb->initialized"
))))
;
4
Assuming 'tvb' is non-null
5
Assuming field 'initialized' is true
6
'?' condition is true
441
442 byte_offset = bit_offset / 8;
443 /* right shift to put bits in place and discard least significant bits */
444 right = bit_offset % 8;
445 /* left shift to get most significant bits from next octet */
446 left = 8 - right;
447
448 if (no_of_bits == -1) {
7
Assuming the condition is false
8
Taking false branch
449 dst_len = _tvb_captured_length_remaining(tvb, byte_offset);
450 remaining_bits = 0;
451 } else {
452 dst_len = no_of_bits / 8;
453 remaining_bits = no_of_bits % 8;
454 if (remaining_bits) {
9
Assuming 'remaining_bits' is 0
455 dst_len++;
456 }
457 }
458
459 /* already aligned -> shortcut */
460 if ((right == 0) && (remaining_bits == 0)) {
10
Assuming 'right' is not equal to 0
461 return tvb_new_subset_length_caplen(tvb, byte_offset, dst_len, dst_len);
462 }
463
464 DISSECTOR_ASSERT(dst_len>0)((void) ((dst_len>0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 464, "dst_len>0"
))))
;
11
Assuming 'dst_len' is > 0
12
'?' condition is true
465
466 if (_tvb_captured_length_remaining(tvb, byte_offset) > dst_len) {
13
Taking false branch
467 /* last octet will get data from trailing octet */
468 src_len = dst_len + 1;
469 } else {
470 /* last octet will be zero padded */
471 src_len = dst_len;
472 }
473
474 data = ensure_contiguous(tvb, byte_offset, src_len); /* tvb_get_ptr */
475
476 /* Do this allocation AFTER tvb_get_ptr() (which could throw an exception) */
477 buf = (uint8_t *)g_malloc(dst_len);
14
Memory is allocated
478
479 for (i = 0; i < (dst_len - 1); i++)
15
Assuming the condition is false
16
Loop condition is false. Execution continues on line 483
480 buf[i] = (data[i] >> right) | (data[i+1] << left);
481
482 /* Special handling for last octet */
483 buf[i] = (data[i] >> right);
17
Assuming right operand of bit shift is less than 32
484 /* Shift most significant bits from trailing octet if available */
485 if (src_len
17.1
'src_len' is <= 'dst_len'
> dst_len)
18
Taking false branch
486 buf[i] |= (data[i+1] << left);
487 /* Preserve only remaining bits in last octet if not multiple of 8 */
488 if (remaining_bits
18.1
'remaining_bits' is 0
)
19
Taking false branch
489 buf[i] &= ((1 << remaining_bits) - 1);
490
491 sub_tvb = tvb_new_child_real_data(tvb, buf, dst_len, dst_len);
20
Potential leak of memory pointed to by 'buf'
492 tvb_set_free_cb(sub_tvb, g_free);
493
494 return sub_tvb;
495}
496
497static tvbuff_t *
498tvb_generic_clone_offset_len(tvbuff_t *tvb, unsigned offset, unsigned len)
499{
500 tvbuff_t *cloned_tvb;
501 uint8_t *data;
502
503 DISSECTOR_ASSERT(tvb_bytes_exist(tvb, offset, len))((void) ((tvb_bytes_exist(tvb, offset, len)) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 503, "tvb_bytes_exist(tvb, offset, len)"
))))
;
504
505 data = (uint8_t *) g_malloc(len);
506
507 tvb_memcpy(tvb, data, offset, len);
508
509 cloned_tvb = tvb_new_real_data(data, len, len);
510 tvb_set_free_cb(cloned_tvb, g_free);
511
512 return cloned_tvb;
513}
514
515tvbuff_t *
516tvb_clone_offset_len(tvbuff_t *tvb, unsigned offset, unsigned len)
517{
518 if (tvb->ops->tvb_clone) {
519 tvbuff_t *cloned_tvb;
520
521 cloned_tvb = tvb->ops->tvb_clone(tvb, offset, len);
522 if (cloned_tvb)
523 return cloned_tvb;
524 }
525
526 return tvb_generic_clone_offset_len(tvb, offset, len);
527}
528
529tvbuff_t *
530tvb_clone(tvbuff_t *tvb)
531{
532 return tvb_clone_offset_len(tvb, 0, tvb->length);
533}
534
535unsigned
536tvb_captured_length(const tvbuff_t *tvb)
537{
538 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 538, "tvb && tvb->initialized"
))))
;
539
540 return tvb->length;
541}
542
543/* For tvbuff internal use */
544static inline int
545_tvb_captured_length_remaining(const tvbuff_t *tvb, const int offset)
546{
547 unsigned abs_offset = 0, rem_length;
548 int exception;
549
550 exception = compute_offset_and_remaining(tvb, offset, &abs_offset, &rem_length);
551 if (exception)
552 return 0;
553
554 return rem_length;
555}
556
557int
558tvb_captured_length_remaining(const tvbuff_t *tvb, const int offset)
559{
560 unsigned abs_offset = 0, rem_length;
561 int exception;
562
563 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 563, "tvb && tvb->initialized"
))))
;
564
565 exception = compute_offset_and_remaining(tvb, offset, &abs_offset, &rem_length);
566 if (exception)
567 return 0;
568
569 return rem_length;
570}
571
572unsigned
573tvb_ensure_captured_length_remaining(const tvbuff_t *tvb, const int offset)
574{
575 unsigned abs_offset = 0, rem_length = 0;
576 int exception;
577
578 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 578, "tvb && tvb->initialized"
))))
;
579
580 exception = compute_offset_and_remaining(tvb, offset, &abs_offset, &rem_length);
581 if (exception)
582 THROW(exception)except_throw(1, (exception), ((void*)0));
583
584 if (rem_length == 0) {
585 /*
586 * This routine ensures there's at least one byte available.
587 * There aren't any bytes available, so throw the appropriate
588 * exception.
589 */
590 if (abs_offset < tvb->contained_length) {
591 THROW(BoundsError)except_throw(1, (1), ((void*)0));
592 } else if (tvb->flags & TVBUFF_FRAGMENT0x00000001) {
593 THROW(FragmentBoundsError)except_throw(1, (4), ((void*)0));
594 } else if (abs_offset < tvb->reported_length) {
595 THROW(ContainedBoundsError)except_throw(1, (2), ((void*)0));
596 } else {
597 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
598 }
599 }
600 return rem_length;
601}
602
603/* Validates that 'length' bytes are available starting from
604 * offset (pos/neg). Does not throw an exception. */
605bool_Bool
606tvb_bytes_exist(const tvbuff_t *tvb, const int offset, const int length)
607{
608 unsigned abs_offset = 0, abs_length;
609 int exception;
610
611 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 611, "tvb && tvb->initialized"
))))
;
612
613 /*
614 * Negative lengths are not possible and indicate a bug (e.g. arithmetic
615 * error or an overly large value from packet data).
616 */
617 if (length < 0)
618 return false0;
619
620 exception = check_offset_length_no_exception(tvb, offset, length, &abs_offset, &abs_length);
621 if (exception)
622 return false0;
623
624 return true1;
625}
626
627/* Validates that 'length' bytes, where 'length' is a 64-bit unsigned
628 * integer, are available starting from offset (pos/neg). Throws an
629 * exception if they aren't. */
630void
631tvb_ensure_bytes_exist64(const tvbuff_t *tvb, const int offset, const uint64_t length)
632{
633 /*
634 * Make sure the value fits in a signed integer; if not, assume
635 * that means that it's too big.
636 */
637 if (length > INT_MAX2147483647) {
638 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
639 }
640
641 /* OK, now cast it and try it with tvb_ensure_bytes_exist(). */
642 tvb_ensure_bytes_exist(tvb, offset, (int)length);
643}
644
645/* Validates that 'length' bytes are available starting from
646 * offset (pos/neg). Throws an exception if they aren't. */
647void
648tvb_ensure_bytes_exist(const tvbuff_t *tvb, const int offset, const int length)
649{
650 unsigned real_offset, end_offset;
651
652 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 652, "tvb && tvb->initialized"
))))
;
653
654 /*
655 * -1 doesn't mean "until end of buffer", as that's pointless
656 * for this routine. We must treat it as a Really Large Positive
657 * Number, so that we throw an exception; we throw
658 * ReportedBoundsError, as if it were past even the end of a
659 * reassembled packet, and past the end of even the data we
660 * didn't capture.
661 *
662 * We do the same with other negative lengths.
663 */
664 if (length < 0) {
665 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
666 }
667
668 /* XXX: Below this point could be replaced with a call to
669 * check_offset_length with no functional change, however this is a
670 * *very* hot path and check_offset_length is not well-optimized for
671 * this case, so we eat some code duplication for a lot of speedup. */
672
673 if (offset >= 0) {
674 /* Positive offset - relative to the beginning of the packet. */
675 if (G_LIKELY((unsigned) offset <= tvb->length)((unsigned) offset <= tvb->length)) {
676 real_offset = offset;
677 } else if ((unsigned) offset <= tvb->contained_length) {
678 THROW(BoundsError)except_throw(1, (1), ((void*)0));
679 } else if (tvb->flags & TVBUFF_FRAGMENT0x00000001) {
680 THROW(FragmentBoundsError)except_throw(1, (4), ((void*)0));
681 } else if ((unsigned) offset <= tvb->reported_length) {
682 THROW(ContainedBoundsError)except_throw(1, (2), ((void*)0));
683 } else {
684 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
685 }
686 }
687 else {
688 /* Negative offset - relative to the end of the packet. */
689 if (G_LIKELY((unsigned) -offset <= tvb->length)((unsigned) -offset <= tvb->length)) {
690 real_offset = tvb->length + offset;
691 } else if ((unsigned) -offset <= tvb->contained_length) {
692 THROW(BoundsError)except_throw(1, (1), ((void*)0));
693 } else if (tvb->flags & TVBUFF_FRAGMENT0x00000001) {
694 THROW(FragmentBoundsError)except_throw(1, (4), ((void*)0));
695 } else if ((unsigned) -offset <= tvb->reported_length) {
696 THROW(ContainedBoundsError)except_throw(1, (2), ((void*)0));
697 } else {
698 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
699 }
700 }
701
702 /*
703 * Compute the offset of the first byte past the length.
704 */
705 end_offset = real_offset + length;
706
707 /*
708 * Check for an overflow
709 */
710 if (end_offset < real_offset)
711 THROW(BoundsError)except_throw(1, (1), ((void*)0));
712
713 if (G_LIKELY(end_offset <= tvb->length)(end_offset <= tvb->length))
714 return;
715 else if (end_offset <= tvb->contained_length)
716 THROW(BoundsError)except_throw(1, (1), ((void*)0));
717 else if (tvb->flags & TVBUFF_FRAGMENT0x00000001)
718 THROW(FragmentBoundsError)except_throw(1, (4), ((void*)0));
719 else if (end_offset <= tvb->reported_length)
720 THROW(ContainedBoundsError)except_throw(1, (2), ((void*)0));
721 else
722 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
723}
724
725bool_Bool
726tvb_offset_exists(const tvbuff_t *tvb, const int offset)
727{
728 unsigned abs_offset = 0;
729 int exception;
730
731 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 731, "tvb && tvb->initialized"
))))
;
732
733 exception = compute_offset(tvb, offset, &abs_offset);
734 if (exception)
735 return false0;
736
737 /* compute_offset only throws an exception on >, not >= because of the
738 * comment above check_offset_length_no_exception, but here we want the
739 * opposite behaviour so we check ourselves... */
740 return abs_offset < tvb->length;
741}
742
743unsigned
744tvb_reported_length(const tvbuff_t *tvb)
745{
746 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 746, "tvb && tvb->initialized"
))))
;
747
748 return tvb->reported_length;
749}
750
751int
752tvb_reported_length_remaining(const tvbuff_t *tvb, const int offset)
753{
754 unsigned abs_offset = 0;
755 int exception;
756
757 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 757, "tvb && tvb->initialized"
))))
;
758
759 exception = compute_offset(tvb, offset, &abs_offset);
760 if (exception)
761 return 0;
762
763 if (tvb->reported_length >= abs_offset)
764 return tvb->reported_length - abs_offset;
765 else
766 return 0;
767}
768
769unsigned
770tvb_ensure_reported_length_remaining(const tvbuff_t *tvb, const int offset)
771{
772 unsigned abs_offset = 0;
773 int exception;
774
775 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 775, "tvb && tvb->initialized"
))))
;
776
777 exception = compute_offset(tvb, offset, &abs_offset);
778 if (exception)
779 THROW(exception)except_throw(1, (exception), ((void*)0));
780
781 if (tvb->reported_length >= abs_offset)
782 return tvb->reported_length - abs_offset;
783 else
784 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
785}
786
787/* Set the reported length of a tvbuff to a given value; used for protocols
788 * whose headers contain an explicit length and where the calling
789 * dissector's payload may include padding as well as the packet for
790 * this protocol.
791 * Also adjusts the available and contained length. */
792void
793tvb_set_reported_length(tvbuff_t *tvb, const unsigned reported_length)
794{
795 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 795, "tvb && tvb->initialized"
))))
;
796
797 if (reported_length > tvb->reported_length)
798 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
799
800 tvb->reported_length = reported_length;
801 if (reported_length < tvb->length)
802 tvb->length = reported_length;
803 if (reported_length < tvb->contained_length)
804 tvb->contained_length = reported_length;
805}
806
807/* Repair a tvbuff where the captured length is greater than the
808 * reported length; such a tvbuff makes no sense, as it's impossible
809 * to capture more data than is in the packet.
810 */
811void
812tvb_fix_reported_length(tvbuff_t *tvb)
813{
814 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 814, "tvb && tvb->initialized"
))))
;
815 DISSECTOR_ASSERT(tvb->reported_length < tvb->length)((void) ((tvb->reported_length < tvb->length) ? (void
)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/tvbuff.c", 815, "tvb->reported_length < tvb->length"
))))
;
816
817 tvb->reported_length = tvb->length;
818 if (tvb->contained_length < tvb->length)
819 tvb->contained_length = tvb->length;
820}
821
822unsigned
823tvb_offset_from_real_beginning_counter(const tvbuff_t *tvb, const unsigned counter)
824{
825 if (tvb->ops->tvb_offset)
826 return tvb->ops->tvb_offset(tvb, counter);
827
828 DISSECTOR_ASSERT_NOT_REACHED()(proto_report_dissector_bug("%s:%u: failed assertion \"DISSECTOR_ASSERT_NOT_REACHED\""
, "epan/tvbuff.c", 828))
;
829 return 0;
830}
831
832unsigned
833tvb_offset_from_real_beginning(const tvbuff_t *tvb)
834{
835 return tvb_offset_from_real_beginning_counter(tvb, 0);
836}
837
838static inline const uint8_t*
839ensure_contiguous_no_exception(tvbuff_t *tvb, const int offset, const int length, int *pexception)
840{
841 unsigned abs_offset = 0, abs_length = 0;
842 int exception;
843
844 exception = check_offset_length_no_exception(tvb, offset, length, &abs_offset, &abs_length);
845 if (exception) {
846 if (pexception)
847 *pexception = exception;
848 return NULL((void*)0);
849 }
850
851 /*
852 * Special case: if the caller (e.g. tvb_get_ptr) requested no data,
853 * then it is acceptable to have an empty tvb (!tvb->real_data).
854 */
855 if (length == 0) {
856 return NULL((void*)0);
857 }
858
859 /*
860 * We know that all the data is present in the tvbuff, so
861 * no exceptions should be thrown.
862 */
863 if (tvb->real_data)
864 return tvb->real_data + abs_offset;
865
866 if (tvb->ops->tvb_get_ptr)
867 return tvb->ops->tvb_get_ptr(tvb, abs_offset, abs_length);
868
869 DISSECTOR_ASSERT_NOT_REACHED()(proto_report_dissector_bug("%s:%u: failed assertion \"DISSECTOR_ASSERT_NOT_REACHED\""
, "epan/tvbuff.c", 869))
;
870 return NULL((void*)0);
871}
872
873static inline const uint8_t*
874ensure_contiguous(tvbuff_t *tvb, const int offset, const int length)
875{
876 int exception = 0;
877 const uint8_t *p;
878
879 p = ensure_contiguous_no_exception(tvb, offset, length, &exception);
880 if (p == NULL((void*)0) && length != 0) {
881 DISSECTOR_ASSERT(exception > 0)((void) ((exception > 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 881, "exception > 0"
))))
;
882 THROW(exception)except_throw(1, (exception), ((void*)0));
883 }
884 return p;
885}
886
887static inline const uint8_t*
888fast_ensure_contiguous(tvbuff_t *tvb, const int offset, const unsigned length)
889{
890 unsigned end_offset;
891 unsigned u_offset;
892
893 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 893, "tvb && tvb->initialized"
))))
;
894 /* We don't check for overflow in this fast path so we only handle simple types */
895 DISSECTOR_ASSERT(length <= 8)((void) ((length <= 8) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 895, "length <= 8"
))))
;
896
897 if (offset < 0 || !tvb->real_data) {
898 return ensure_contiguous(tvb, offset, length);
899 }
900
901 u_offset = offset;
902 end_offset = u_offset + length;
903
904 if (G_LIKELY(end_offset <= tvb->length)(end_offset <= tvb->length)) {
905 return tvb->real_data + u_offset;
906 } else if (end_offset <= tvb->contained_length) {
907 THROW(BoundsError)except_throw(1, (1), ((void*)0));
908 } else if (tvb->flags & TVBUFF_FRAGMENT0x00000001) {
909 THROW(FragmentBoundsError)except_throw(1, (4), ((void*)0));
910 } else if (end_offset <= tvb->reported_length) {
911 THROW(ContainedBoundsError)except_throw(1, (2), ((void*)0));
912 } else {
913 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
914 }
915 /* not reached */
916 return NULL((void*)0);
917}
918
919
920
921/************** ACCESSORS **************/
922
923void *
924tvb_memcpy(tvbuff_t *tvb, void *target, const int offset, size_t length)
925{
926 unsigned abs_offset = 0, abs_length = 0;
927
928 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 928, "tvb && tvb->initialized"
))))
;
929
930 /*
931 * XXX - we should eliminate the "length = -1 means 'to the end
932 * of the tvbuff'" convention, and use other means to achieve
933 * that; this would let us eliminate a bunch of checks for
934 * negative lengths in cases where the protocol has a 32-bit
935 * length field.
936 *
937 * Allowing -1 but throwing an assertion on other negative
938 * lengths is a bit more work with the length being a size_t;
939 * instead, we check for a length <= 2^31-1.
940 */
941 DISSECTOR_ASSERT(length <= 0x7FFFFFFF)((void) ((length <= 0x7FFFFFFF) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 941, "length <= 0x7FFFFFFF"
))))
;
942 check_offset_length(tvb, offset, (int) length, &abs_offset, &abs_length);
943
944 if (target && tvb->real_data) {
945 return memcpy(target, tvb->real_data + abs_offset, abs_length);
946 }
947
948 if (target && tvb->ops->tvb_memcpy)
949 return tvb->ops->tvb_memcpy(tvb, target, abs_offset, abs_length);
950
951 /*
952 * If the length is 0, there's nothing to do.
953 * (tvb->real_data could be null if it's allocated with
954 * a size of length.)
955 */
956 if (length != 0) {
957 /*
958 * XXX, fallback to slower method
959 */
960 DISSECTOR_ASSERT_NOT_REACHED()(proto_report_dissector_bug("%s:%u: failed assertion \"DISSECTOR_ASSERT_NOT_REACHED\""
, "epan/tvbuff.c", 960))
;
961 }
962 return NULL((void*)0);
963}
964
965
966/*
967 * XXX - this doesn't treat a length of -1 as an error.
968 * If it did, this could replace some code that calls
969 * "tvb_ensure_bytes_exist()" and then allocates a buffer and copies
970 * data to it.
971 *
972 * "composite_get_ptr()" depends on -1 not being
973 * an error; does anything else depend on this routine treating -1 as
974 * meaning "to the end of the buffer"?
975 *
976 * If scope is NULL, memory is allocated with g_malloc() and user must
977 * explicitly free it with g_free().
978 * If scope is not NULL, memory is allocated with the corresponding pool
979 * lifetime.
980 */
981void *
982tvb_memdup(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, size_t length)
983{
984 unsigned abs_offset = 0, abs_length = 0;
985 void *duped;
986
987 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 987, "tvb && tvb->initialized"
))))
;
988
989 check_offset_length(tvb, offset, (int) length, &abs_offset, &abs_length);
990
991 if (abs_length == 0)
992 return NULL((void*)0);
993
994 duped = wmem_alloc(scope, abs_length);
995 return tvb_memcpy(tvb, duped, abs_offset, abs_length);
996}
997
998
999
1000const uint8_t*
1001tvb_get_ptr(tvbuff_t *tvb, const int offset, const int length)
1002{
1003 return ensure_contiguous(tvb, offset, length);
1004}
1005
1006/* ---------------- */
1007uint8_t
1008tvb_get_uint8(tvbuff_t *tvb, const int offset)
1009{
1010 const uint8_t *ptr;
1011
1012 ptr = fast_ensure_contiguous(tvb, offset, 1);
1013 return *ptr;
1014}
1015
1016int8_t
1017tvb_get_int8(tvbuff_t *tvb, const int offset)
1018{
1019 const uint8_t *ptr;
1020
1021 ptr = fast_ensure_contiguous(tvb, offset, 1);
1022 return *ptr;
1023}
1024
1025uint16_t
1026tvb_get_ntohs(tvbuff_t *tvb, const int offset)
1027{
1028 const uint8_t *ptr;
1029
1030 ptr = fast_ensure_contiguous(tvb, offset, 2);
1031 return pntohu16(ptr);
1032}
1033
1034int16_t
1035tvb_get_ntohis(tvbuff_t *tvb, const int offset)
1036{
1037 const uint8_t *ptr;
1038
1039 ptr = fast_ensure_contiguous(tvb, offset, 2);
1040 return pntohu16(ptr);
1041}
1042
1043uint32_t
1044tvb_get_ntoh24(tvbuff_t *tvb, const int offset)
1045{
1046 const uint8_t *ptr;
1047
1048 ptr = fast_ensure_contiguous(tvb, offset, 3);
1049 return pntohu24(ptr);
1050}
1051
1052int32_t
1053tvb_get_ntohi24(tvbuff_t *tvb, const int offset)
1054{
1055 uint32_t ret;
1056
1057 ret = ws_sign_ext32(tvb_get_ntoh24(tvb, offset), 24);
1058
1059 return (int32_t)ret;
1060}
1061
1062uint32_t
1063tvb_get_ntohl(tvbuff_t *tvb, const int offset)
1064{
1065 const uint8_t *ptr;
1066
1067 ptr = fast_ensure_contiguous(tvb, offset, 4);
1068 return pntohu32(ptr);
1069}
1070
1071int32_t
1072tvb_get_ntohil(tvbuff_t *tvb, const int offset)
1073{
1074 const uint8_t *ptr;
1075
1076 ptr = fast_ensure_contiguous(tvb, offset, 4);
1077 return pntohu32(ptr);
1078}
1079
1080uint64_t
1081tvb_get_ntoh40(tvbuff_t *tvb, const int offset)
1082{
1083 const uint8_t *ptr;
1084
1085 ptr = fast_ensure_contiguous(tvb, offset, 5);
1086 return pntohu40(ptr);
1087}
1088
1089int64_t
1090tvb_get_ntohi40(tvbuff_t *tvb, const int offset)
1091{
1092 uint64_t ret;
1093
1094 ret = ws_sign_ext64(tvb_get_ntoh40(tvb, offset), 40);
1095
1096 return (int64_t)ret;
1097}
1098
1099uint64_t
1100tvb_get_ntoh48(tvbuff_t *tvb, const int offset)
1101{
1102 const uint8_t *ptr;
1103
1104 ptr = fast_ensure_contiguous(tvb, offset, 6);
1105 return pntohu48(ptr);
1106}
1107
1108int64_t
1109tvb_get_ntohi48(tvbuff_t *tvb, const int offset)
1110{
1111 uint64_t ret;
1112
1113 ret = ws_sign_ext64(tvb_get_ntoh48(tvb, offset), 48);
1114
1115 return (int64_t)ret;
1116}
1117
1118uint64_t
1119tvb_get_ntoh56(tvbuff_t *tvb, const int offset)
1120{
1121 const uint8_t *ptr;
1122
1123 ptr = fast_ensure_contiguous(tvb, offset, 7);
1124 return pntohu56(ptr);
1125}
1126
1127int64_t
1128tvb_get_ntohi56(tvbuff_t *tvb, const int offset)
1129{
1130 uint64_t ret;
1131
1132 ret = ws_sign_ext64(tvb_get_ntoh56(tvb, offset), 56);
1133
1134 return (int64_t)ret;
1135}
1136
1137uint64_t
1138tvb_get_ntoh64(tvbuff_t *tvb, const int offset)
1139{
1140 const uint8_t *ptr;
1141
1142 ptr = fast_ensure_contiguous(tvb, offset, 8);
1143 return pntohu64(ptr);
1144}
1145
1146int64_t
1147tvb_get_ntohi64(tvbuff_t *tvb, const int offset)
1148{
1149 const uint8_t *ptr;
1150
1151 ptr = fast_ensure_contiguous(tvb, offset, 8);
1152 return pntohu64(ptr);
1153}
1154
1155uint16_t
1156tvb_get_uint16(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1157 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1158 return tvb_get_letohs(tvb, offset);
1159 } else {
1160 return tvb_get_ntohs(tvb, offset);
1161 }
1162}
1163
1164int16_t
1165tvb_get_int16(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1166 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1167 return tvb_get_letohis(tvb, offset);
1168 } else {
1169 return tvb_get_ntohis(tvb, offset);
1170 }
1171}
1172
1173uint32_t
1174tvb_get_uint24(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1175 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1176 return tvb_get_letoh24(tvb, offset);
1177 } else {
1178 return tvb_get_ntoh24(tvb, offset);
1179 }
1180}
1181
1182int32_t
1183tvb_get_int24(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1184 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1185 return tvb_get_letohi24(tvb, offset);
1186 } else {
1187 return tvb_get_ntohi24(tvb, offset);
1188 }
1189}
1190
1191uint32_t
1192tvb_get_uint32(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1193 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1194 return tvb_get_letohl(tvb, offset);
1195 } else {
1196 return tvb_get_ntohl(tvb, offset);
1197 }
1198}
1199
1200int32_t
1201tvb_get_int32(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1202 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1203 return tvb_get_letohil(tvb, offset);
1204 } else {
1205 return tvb_get_ntohil(tvb, offset);
1206 }
1207}
1208
1209uint64_t
1210tvb_get_uint40(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1211 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1212 return tvb_get_letoh40(tvb, offset);
1213 } else {
1214 return tvb_get_ntoh40(tvb, offset);
1215 }
1216}
1217
1218int64_t
1219tvb_get_int40(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1220 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1221 return tvb_get_letohi40(tvb, offset);
1222 } else {
1223 return tvb_get_ntohi40(tvb, offset);
1224 }
1225}
1226
1227uint64_t
1228tvb_get_uint48(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1229 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1230 return tvb_get_letoh48(tvb, offset);
1231 } else {
1232 return tvb_get_ntoh48(tvb, offset);
1233 }
1234}
1235
1236int64_t
1237tvb_get_int48(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1238 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1239 return tvb_get_letohi48(tvb, offset);
1240 } else {
1241 return tvb_get_ntohi48(tvb, offset);
1242 }
1243}
1244
1245uint64_t
1246tvb_get_uint56(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1247 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1248 return tvb_get_letoh56(tvb, offset);
1249 } else {
1250 return tvb_get_ntoh56(tvb, offset);
1251 }
1252}
1253
1254int64_t
1255tvb_get_int56(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1256 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1257 return tvb_get_letohi56(tvb, offset);
1258 } else {
1259 return tvb_get_ntohi56(tvb, offset);
1260 }
1261}
1262
1263uint64_t
1264tvb_get_uint64(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1265 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1266 return tvb_get_letoh64(tvb, offset);
1267 } else {
1268 return tvb_get_ntoh64(tvb, offset);
1269 }
1270}
1271
1272uint64_t
1273tvb_get_uint64_with_length(tvbuff_t *tvb, const int offset, unsigned length, const unsigned encoding)
1274{
1275 uint64_t value;
1276
1277 switch (length) {
1278
1279 case 1:
1280 value = tvb_get_uint8(tvb, offset);
1281 break;
1282
1283 case 2:
1284 value = (encoding & ENC_LITTLE_ENDIAN0x80000000) ? tvb_get_letohs(tvb, offset)
1285 : tvb_get_ntohs(tvb, offset);
1286 break;
1287
1288 case 3:
1289 value = (encoding & ENC_LITTLE_ENDIAN0x80000000) ? tvb_get_letoh24(tvb, offset)
1290 : tvb_get_ntoh24(tvb, offset);
1291 break;
1292
1293 case 4:
1294 value = (encoding & ENC_LITTLE_ENDIAN0x80000000) ? tvb_get_letohl(tvb, offset)
1295 : tvb_get_ntohl(tvb, offset);
1296 break;
1297
1298 case 5:
1299 value = (encoding & ENC_LITTLE_ENDIAN0x80000000) ? tvb_get_letoh40(tvb, offset)
1300 : tvb_get_ntoh40(tvb, offset);
1301 break;
1302
1303 case 6:
1304 value = (encoding & ENC_LITTLE_ENDIAN0x80000000) ? tvb_get_letoh48(tvb, offset)
1305 : tvb_get_ntoh48(tvb, offset);
1306 break;
1307
1308 case 7:
1309 value = (encoding & ENC_LITTLE_ENDIAN0x80000000) ? tvb_get_letoh56(tvb, offset)
1310 : tvb_get_ntoh56(tvb, offset);
1311 break;
1312
1313 case 8:
1314 value = (encoding & ENC_LITTLE_ENDIAN0x80000000) ? tvb_get_letoh64(tvb, offset)
1315 : tvb_get_ntoh64(tvb, offset);
1316 break;
1317
1318 default:
1319 if (length < 1) {
1320 value = 0;
1321 } else {
1322 value = (encoding & ENC_LITTLE_ENDIAN0x80000000) ? tvb_get_letoh64(tvb, offset)
1323 : tvb_get_ntoh64(tvb, offset);
1324 }
1325 break;
1326 }
1327 return value;
1328}
1329
1330int64_t
1331tvb_get_int64(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1332 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1333 return tvb_get_letohi64(tvb, offset);
1334 } else {
1335 return tvb_get_ntohi64(tvb, offset);
1336 }
1337}
1338
1339float
1340tvb_get_ieee_float(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1341 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1342 return tvb_get_letohieee_float(tvb, offset);
1343 } else {
1344 return tvb_get_ntohieee_float(tvb, offset);
1345 }
1346}
1347
1348double
1349tvb_get_ieee_double(tvbuff_t *tvb, const int offset, const unsigned encoding) {
1350 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1351 return tvb_get_letohieee_double(tvb, offset);
1352 } else {
1353 return tvb_get_ntohieee_double(tvb, offset);
1354 }
1355}
1356
1357/*
1358 * Stuff for IEEE float handling on platforms that don't have IEEE
1359 * format as the native floating-point format.
1360 *
1361 * For now, we treat only the VAX as such a platform.
1362 *
1363 * XXX - other non-IEEE boxes that can run UN*X include some Crays,
1364 * and possibly other machines. However, I don't know whether there
1365 * are any other machines that could run Wireshark and that don't use
1366 * IEEE format. As far as I know, all of the main current and past
1367 * commercial microprocessor families on which OSes that support
1368 * Wireshark can run use IEEE format (x86, ARM, 68k, SPARC, MIPS,
1369 * PA-RISC, Alpha, IA-64, and so on), and it appears that the official
1370 * Linux port to System/390 and zArchitecture uses IEEE format floating-
1371 * point rather than IBM hex floating-point (not a huge surprise), so
1372 * I'm not sure that leaves any 32-bit or larger UN*X or Windows boxes,
1373 * other than VAXes, that don't use IEEE format. If you're not running
1374 * UN*X or Windows, the floating-point format is probably going to be
1375 * the least of your problems in a port.
1376 */
1377
1378#if defined(vax)
1379
1380#include <math.h>
1381
1382/*
1383 * Single-precision.
1384 */
1385#define IEEE_SP_NUMBER_WIDTH 32 /* bits in number */
1386#define IEEE_SP_EXP_WIDTH 8 /* bits in exponent */
1387#define IEEE_SP_MANTISSA_WIDTH 23 /* IEEE_SP_NUMBER_WIDTH - 1 - IEEE_SP_EXP_WIDTH */
1388
1389#define IEEE_SP_SIGN_MASK 0x80000000
1390#define IEEE_SP_EXPONENT_MASK 0x7F800000
1391#define IEEE_SP_MANTISSA_MASK 0x007FFFFF
1392#define IEEE_SP_INFINITY IEEE_SP_EXPONENT_MASK
1393
1394#define IEEE_SP_IMPLIED_BIT (1 << IEEE_SP_MANTISSA_WIDTH)
1395#define IEEE_SP_INFINITE ((1 << IEEE_SP_EXP_WIDTH) - 1)
1396#define IEEE_SP_BIAS ((1 << (IEEE_SP_EXP_WIDTH - 1)) - 1)
1397
1398static int
1399ieee_float_is_zero(const uint32_t w)
1400{
1401 return ((w & ~IEEE_SP_SIGN_MASK) == 0);
1402}
1403
1404static float
1405get_ieee_float(const uint32_t w)
1406{
1407 long sign;
1408 long exponent;
1409 long mantissa;
1410
1411 sign = w & IEEE_SP_SIGN_MASK;
1412 exponent = w & IEEE_SP_EXPONENT_MASK;
1413 mantissa = w & IEEE_SP_MANTISSA_MASK;
1414
1415 if (ieee_float_is_zero(w)) {
1416 /* number is zero, unnormalized, or not-a-number */
1417 return 0.0;
1418 }
1419#if 0
1420 /*
1421 * XXX - how to handle this?
1422 */
1423 if (IEEE_SP_INFINITY == exponent) {
1424 /*
1425 * number is positive or negative infinity, or a special value
1426 */
1427 return (sign? MINUS_INFINITY: PLUS_INFINITY);
1428 }
1429#endif
1430
1431 exponent = ((exponent >> IEEE_SP_MANTISSA_WIDTH) - IEEE_SP_BIAS) -
1432 IEEE_SP_MANTISSA_WIDTH;
1433 mantissa |= IEEE_SP_IMPLIED_BIT;
1434
1435 if (sign)
1436 return -mantissa * pow(2, exponent);
1437 else
1438 return mantissa * pow(2, exponent);
1439}
1440
1441/*
1442 * Double-precision.
1443 * We assume that if you don't have IEEE floating-point, you have a
1444 * compiler that understands 64-bit integral quantities.
1445 */
1446#define IEEE_DP_NUMBER_WIDTH 64 /* bits in number */
1447#define IEEE_DP_EXP_WIDTH 11 /* bits in exponent */
1448#define IEEE_DP_MANTISSA_WIDTH 52 /* IEEE_DP_NUMBER_WIDTH - 1 - IEEE_DP_EXP_WIDTH */
1449
1450#define IEEE_DP_SIGN_MASK INT64_C(0x8000000000000000)0x8000000000000000L
1451#define IEEE_DP_EXPONENT_MASK INT64_C(0x7FF0000000000000)0x7FF0000000000000L
1452#define IEEE_DP_MANTISSA_MASK INT64_C(0x000FFFFFFFFFFFFF)0x000FFFFFFFFFFFFFL
1453#define IEEE_DP_INFINITY IEEE_DP_EXPONENT_MASK
1454
1455#define IEEE_DP_IMPLIED_BIT (INT64_C(1)1L << IEEE_DP_MANTISSA_WIDTH)
1456#define IEEE_DP_INFINITE ((1 << IEEE_DP_EXP_WIDTH) - 1)
1457#define IEEE_DP_BIAS ((1 << (IEEE_DP_EXP_WIDTH - 1)) - 1)
1458
1459static int
1460ieee_double_is_zero(const uint64_t w)
1461{
1462 return ((w & ~IEEE_SP_SIGN_MASK) == 0);
1463}
1464
1465static double
1466get_ieee_double(const uint64_t w)
1467{
1468 int64_t sign;
1469 int64_t exponent;
1470 int64_t mantissa;
1471
1472 sign = w & IEEE_DP_SIGN_MASK;
1473 exponent = w & IEEE_DP_EXPONENT_MASK;
1474 mantissa = w & IEEE_DP_MANTISSA_MASK;
1475
1476 if (ieee_double_is_zero(w)) {
1477 /* number is zero, unnormalized, or not-a-number */
1478 return 0.0;
1479 }
1480#if 0
1481 /*
1482 * XXX - how to handle this?
1483 */
1484 if (IEEE_DP_INFINITY == exponent) {
1485 /*
1486 * number is positive or negative infinity, or a special value
1487 */
1488 return (sign? MINUS_INFINITY: PLUS_INFINITY);
1489 }
1490#endif
1491
1492 exponent = ((exponent >> IEEE_DP_MANTISSA_WIDTH) - IEEE_DP_BIAS) -
1493 IEEE_DP_MANTISSA_WIDTH;
1494 mantissa |= IEEE_DP_IMPLIED_BIT;
1495
1496 if (sign)
1497 return -mantissa * pow(2, exponent);
1498 else
1499 return mantissa * pow(2, exponent);
1500}
1501#endif
1502
1503/*
1504 * Fetches an IEEE single-precision floating-point number, in
1505 * big-endian form, and returns a "float".
1506 *
1507 * XXX - should this be "double", in case there are IEEE single-
1508 * precision numbers that won't fit in some platform's native
1509 * "float" format?
1510 */
1511float
1512tvb_get_ntohieee_float(tvbuff_t *tvb, const int offset)
1513{
1514#if defined(vax)
1515 return get_ieee_float(tvb_get_ntohl(tvb, offset));
1516#else
1517 union {
1518 float f;
1519 uint32_t w;
1520 } ieee_fp_union;
1521
1522 ieee_fp_union.w = tvb_get_ntohl(tvb, offset);
1523 return ieee_fp_union.f;
1524#endif
1525}
1526
1527/*
1528 * Fetches an IEEE double-precision floating-point number, in
1529 * big-endian form, and returns a "double".
1530 */
1531double
1532tvb_get_ntohieee_double(tvbuff_t *tvb, const int offset)
1533{
1534#if defined(vax)
1535 union {
1536 uint32_t w[2];
1537 uint64_t dw;
1538 } ieee_fp_union;
1539#else
1540 union {
1541 double d;
1542 uint32_t w[2];
1543 } ieee_fp_union;
1544#endif
1545
1546#if G_BYTE_ORDER1234 == G_BIG_ENDIAN4321
1547 ieee_fp_union.w[0] = tvb_get_ntohl(tvb, offset);
1548 ieee_fp_union.w[1] = tvb_get_ntohl(tvb, offset+4);
1549#else
1550 ieee_fp_union.w[0] = tvb_get_ntohl(tvb, offset+4);
1551 ieee_fp_union.w[1] = tvb_get_ntohl(tvb, offset);
1552#endif
1553#if defined(vax)
1554 return get_ieee_double(ieee_fp_union.dw);
1555#else
1556 return ieee_fp_union.d;
1557#endif
1558}
1559
1560uint16_t
1561tvb_get_letohs(tvbuff_t *tvb, const int offset)
1562{
1563 const uint8_t *ptr;
1564
1565 ptr = fast_ensure_contiguous(tvb, offset, 2);
1566 return pletohu16(ptr);
1567}
1568
1569int16_t
1570tvb_get_letohis(tvbuff_t *tvb, const int offset)
1571{
1572 const uint8_t *ptr;
1573
1574 ptr = fast_ensure_contiguous(tvb, offset, 2);
1575 return pletohu16(ptr);
1576}
1577
1578uint32_t
1579tvb_get_letoh24(tvbuff_t *tvb, const int offset)
1580{
1581 const uint8_t *ptr;
1582
1583 ptr = fast_ensure_contiguous(tvb, offset, 3);
1584 return pletohu24(ptr);
1585}
1586
1587int32_t
1588tvb_get_letohi24(tvbuff_t *tvb, const int offset)
1589{
1590 uint32_t ret;
1591
1592 ret = ws_sign_ext32(tvb_get_letoh24(tvb, offset), 24);
1593
1594 return (int32_t)ret;
1595}
1596
1597uint32_t
1598tvb_get_letohl(tvbuff_t *tvb, const int offset)
1599{
1600 const uint8_t *ptr;
1601
1602 ptr = fast_ensure_contiguous(tvb, offset, 4);
1603 return pletohu32(ptr);
1604}
1605
1606int32_t
1607tvb_get_letohil(tvbuff_t *tvb, const int offset)
1608{
1609 const uint8_t *ptr;
1610
1611 ptr = fast_ensure_contiguous(tvb, offset, 4);
1612 return pletohu32(ptr);
1613}
1614
1615uint64_t
1616tvb_get_letoh40(tvbuff_t *tvb, const int offset)
1617{
1618 const uint8_t *ptr;
1619
1620 ptr = fast_ensure_contiguous(tvb, offset, 5);
1621 return pletohu40(ptr);
1622}
1623
1624int64_t
1625tvb_get_letohi40(tvbuff_t *tvb, const int offset)
1626{
1627 uint64_t ret;
1628
1629 ret = ws_sign_ext64(tvb_get_letoh40(tvb, offset), 40);
1630
1631 return (int64_t)ret;
1632}
1633
1634uint64_t
1635tvb_get_letoh48(tvbuff_t *tvb, const int offset)
1636{
1637 const uint8_t *ptr;
1638
1639 ptr = fast_ensure_contiguous(tvb, offset, 6);
1640 return pletohu48(ptr);
1641}
1642
1643int64_t
1644tvb_get_letohi48(tvbuff_t *tvb, const int offset)
1645{
1646 uint64_t ret;
1647
1648 ret = ws_sign_ext64(tvb_get_letoh48(tvb, offset), 48);
1649
1650 return (int64_t)ret;
1651}
1652
1653uint64_t
1654tvb_get_letoh56(tvbuff_t *tvb, const int offset)
1655{
1656 const uint8_t *ptr;
1657
1658 ptr = fast_ensure_contiguous(tvb, offset, 7);
1659 return pletohu56(ptr);
1660}
1661
1662int64_t
1663tvb_get_letohi56(tvbuff_t *tvb, const int offset)
1664{
1665 uint64_t ret;
1666
1667 ret = ws_sign_ext64(tvb_get_letoh56(tvb, offset), 56);
1668
1669 return (int64_t)ret;
1670}
1671
1672uint64_t
1673tvb_get_letoh64(tvbuff_t *tvb, const int offset)
1674{
1675 const uint8_t *ptr;
1676
1677 ptr = fast_ensure_contiguous(tvb, offset, 8);
1678 return pletohu64(ptr);
1679}
1680
1681int64_t
1682tvb_get_letohi64(tvbuff_t *tvb, const int offset)
1683{
1684 const uint8_t *ptr;
1685
1686 ptr = fast_ensure_contiguous(tvb, offset, 8);
1687 return pletohu64(ptr);
1688}
1689
1690/*
1691 * Fetches an IEEE single-precision floating-point number, in
1692 * little-endian form, and returns a "float".
1693 *
1694 * XXX - should this be "double", in case there are IEEE single-
1695 * precision numbers that won't fit in some platform's native
1696 * "float" format?
1697 */
1698float
1699tvb_get_letohieee_float(tvbuff_t *tvb, const int offset)
1700{
1701#if defined(vax)
1702 return get_ieee_float(tvb_get_letohl(tvb, offset));
1703#else
1704 union {
1705 float f;
1706 uint32_t w;
1707 } ieee_fp_union;
1708
1709 ieee_fp_union.w = tvb_get_letohl(tvb, offset);
1710 return ieee_fp_union.f;
1711#endif
1712}
1713
1714/*
1715 * Fetches an IEEE double-precision floating-point number, in
1716 * little-endian form, and returns a "double".
1717 */
1718double
1719tvb_get_letohieee_double(tvbuff_t *tvb, const int offset)
1720{
1721#if defined(vax)
1722 union {
1723 uint32_t w[2];
1724 uint64_t dw;
1725 } ieee_fp_union;
1726#else
1727 union {
1728 double d;
1729 uint32_t w[2];
1730 } ieee_fp_union;
1731#endif
1732
1733#if G_BYTE_ORDER1234 == G_BIG_ENDIAN4321
1734 ieee_fp_union.w[0] = tvb_get_letohl(tvb, offset+4);
1735 ieee_fp_union.w[1] = tvb_get_letohl(tvb, offset);
1736#else
1737 ieee_fp_union.w[0] = tvb_get_letohl(tvb, offset);
1738 ieee_fp_union.w[1] = tvb_get_letohl(tvb, offset+4);
1739#endif
1740#if defined(vax)
1741 return get_ieee_double(ieee_fp_union.dw);
1742#else
1743 return ieee_fp_union.d;
1744#endif
1745}
1746
1747/* This function is a slight misnomer. It accepts all encodings that are
1748 * ASCII "enough", which means encodings that are the same as US-ASCII
1749 * for textual representations of dates and hex bytes; i.e., the same
1750 * for the hex digits and Z (in practice, all alphanumerics), and the
1751 * four separators ':' '-' '.' and ' '
1752 * That means that any encoding that keeps the ISO/IEC 646 invariant
1753 * characters the same (including the T.61 8 bit encoding and multibyte
1754 * encodings like EUC-KR and GB18030) are OK, even if they replace characters
1755 * like '$' '#' and '\' with national variants, but not encodings like UTF-16
1756 * that include extra null bytes.
1757 * For our current purposes, the unpacked GSM 7-bit default alphabet (but not
1758 * all National Language Shift Tables) also satisfies this requirement, but
1759 * note that it does *not* keep all ISO/IEC 646 invariant characters the same.
1760 * If this internal function gets used for additional purposes than currently,
1761 * the set of encodings that it accepts could change.
1762 * */
1763static inline void
1764validate_single_byte_ascii_encoding(const unsigned encoding)
1765{
1766 const unsigned enc = encoding & ~ENC_CHARENCODING_MASK0x0000FFFE;
1767
1768 switch (enc) {
1769 case ENC_UTF_160x00000004:
1770 case ENC_UCS_20x00000006:
1771 case ENC_UCS_40x00000008:
1772 case ENC_3GPP_TS_23_038_7BITS_PACKED0x0000002C:
1773 case ENC_ASCII_7BITS0x00000034:
1774 case ENC_EBCDIC0x0000002E:
1775 case ENC_EBCDIC_CP0370x00000038:
1776 case ENC_EBCDIC_CP5000x00000060:
1777 case ENC_BCD_DIGITS_0_90x00000044:
1778 case ENC_KEYPAD_ABC_TBCD0x00000046:
1779 case ENC_KEYPAD_BC_TBCD0x00000048:
1780 case ENC_ETSI_TS_102_221_ANNEX_A0x0000004E:
1781 case ENC_APN_STR0x00000054:
1782 case ENC_DECT_STANDARD_4BITS_TBCD0x00000058:
1783 REPORT_DISSECTOR_BUG("Invalid string encoding type passed to tvb_get_string_XXX")proto_report_dissector_bug("Invalid string encoding type passed to tvb_get_string_XXX"
)
;
1784 break;
1785 default:
1786 break;
1787 }
1788 /* make sure something valid was set */
1789 if (enc == 0)
1790 REPORT_DISSECTOR_BUG("No string encoding type passed to tvb_get_string_XXX")proto_report_dissector_bug("No string encoding type passed to tvb_get_string_XXX"
)
;
1791}
1792
1793GByteArray*
1794tvb_get_string_bytes(tvbuff_t *tvb, const int offset, const int length,
1795 const unsigned encoding, GByteArray *bytes, int *endoff)
1796{
1797 char *ptr;
1798 const char *begin;
1799 const char *end = NULL((void*)0);
1800 GByteArray *retval = NULL((void*)0);
1801
1802 validate_single_byte_ascii_encoding(encoding);
1803
1804 ptr = (char*) tvb_get_raw_string(NULL((void*)0), tvb, offset, length);
1805 begin = ptr;
1806
1807 if (endoff) *endoff = offset;
1808
1809 while (*begin == ' ') begin++;
1810
1811 if (*begin && bytes) {
1812 if (hex_str_to_bytes_encoding(begin, bytes, &end, encoding, false0)) {
1813 if (bytes->len > 0) {
1814 if (endoff) *endoff = offset + (int)(end - ptr);
1815 retval = bytes;
1816 }
1817 }
1818 }
1819
1820 wmem_free(NULL((void*)0), ptr);
1821
1822 return retval;
1823}
1824
1825static bool_Bool
1826parse_month_name(const char *name, int *tm_mon)
1827{
1828 static const char months[][4] = { "Jan", "Feb", "Mar", "Apr", "May",
1829 "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
1830 for (int i = 0; i < 12; i++) {
1831 if (memcmp(months[i], name, 4) == 0) {
1832 *tm_mon = i;
1833 return true1;
1834 }
1835 }
1836 return false0;
1837}
1838
1839/*
1840 * Is the character a WSP character, as per RFC 5234? (space or tab).
1841 */
1842#define IS_WSP(c)((c) == ' ' || (c) == '\t') ((c) == ' ' || (c) == '\t')
1843
1844/* support hex-encoded time values? */
1845nstime_t*
1846tvb_get_string_time(tvbuff_t *tvb, const int offset, const int length,
1847 const unsigned encoding, nstime_t *ns, int *endoff)
1848{
1849 char *begin;
1850 const char *ptr;
1851 const char *end = NULL((void*)0);
1852 int num_chars = 0;
1853 int utc_offset = 0;
1854
1855 validate_single_byte_ascii_encoding(encoding);
1856
1857 DISSECTOR_ASSERT(ns)((void) ((ns) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/tvbuff.c", 1857, "ns"))))
;
1858
1859 begin = (char*) tvb_get_raw_string(NULL((void*)0), tvb, offset, length);
1860 ptr = begin;
1861
1862 while (IS_WSP(*ptr)((*ptr) == ' ' || (*ptr) == '\t'))
1863 ptr++;
1864
1865 if (*ptr) {
1866 if ((encoding & ENC_ISO_8601_DATE_TIME0x00030000) == ENC_ISO_8601_DATE_TIME0x00030000) {
1867 if (!(end = iso8601_to_nstime(ns, ptr, ISO8601_DATETIME))) {
1868
1869
1870 goto fail;
1871 }
1872 } else if ((encoding & ENC_ISO_8601_DATE_TIME_BASIC0x00100000) == ENC_ISO_8601_DATE_TIME_BASIC0x00100000) {
1873 if (!(end = iso8601_to_nstime(ns, ptr, ISO8601_DATETIME_BASIC))) {
1874
1875
1876 goto fail;
1877 }
1878 } else {
1879 struct tm tm;
1880
1881 memset(&tm, 0, sizeof(tm));
1882 tm.tm_isdst = -1;
1883 ns->secs = 0;
1884 ns->nsecs = 0;
1885
1886 /* note: sscanf is known to be inconsistent across platforms with respect
1887 to whether a %n is counted as a return value or not, so we have to use
1888 '>=' a lot */
1889 if (encoding & ENC_ISO_8601_DATE0x00010000) {
1890 /* 2014-04-07 */
1891 if (sscanf(ptr, "%d-%d-%d%n",
1892 &tm.tm_year,
1893 &tm.tm_mon,
1894 &tm.tm_mday,
1895 &num_chars) >= 3)
1896 {
1897 end = ptr + num_chars;
1898 tm.tm_mon--;
1899 if (tm.tm_year > 1900) tm.tm_year -= 1900;
1900 } else {
1901 goto fail;
1902 }
1903 }
1904 else if (encoding & ENC_ISO_8601_TIME0x00020000) {
1905 /* 2014-04-07 */
1906 if (sscanf(ptr, "%d:%d:%d%n",
1907 &tm.tm_hour,
1908 &tm.tm_min,
1909 &tm.tm_sec,
1910 &num_chars) >= 2)
1911 {
1912 /* what should we do about day/month/year? */
1913 /* setting it to "now" for now */
1914 time_t time_now = time(NULL((void*)0));
1915 struct tm *tm_now = gmtime(&time_now);
1916 if (tm_now != NULL((void*)0)) {
1917 tm.tm_year = tm_now->tm_year;
1918 tm.tm_mon = tm_now->tm_mon;
1919 tm.tm_mday = tm_now->tm_mday;
1920 } else {
1921 /* The second before the Epoch */
1922 tm.tm_year = 69;
1923 tm.tm_mon = 12;
1924 tm.tm_mday = 31;
1925 }
1926 end = ptr + num_chars;
1927 } else {
1928 goto fail;
1929 }
1930 }
1931 else if (encoding & ENC_IMF_DATE_TIME0x00040000) {
1932 /*
1933 * Match [dow,] day month year hh:mm[:ss] with
1934 * two-digit years (RFC 822) or four-digit
1935 * years (RFCs 1123, 2822, 5822). Skip
1936 * the day of week since it is locale
1937 * dependent and does not affect the resulting
1938 * date anyway.
1939 */
1940 if (g_ascii_isalpha(ptr[0])((g_ascii_table[(guchar) (ptr[0])] & G_ASCII_ALPHA) != 0) && g_ascii_isalpha(ptr[1])((g_ascii_table[(guchar) (ptr[1])] & G_ASCII_ALPHA) != 0) && g_ascii_isalpha(ptr[2])((g_ascii_table[(guchar) (ptr[2])] & G_ASCII_ALPHA) != 0) && ptr[3] == ',')
1941 ptr += 4; /* Skip day of week. */
1942
1943 /*
1944 * Parse the day-of-month and month
1945 * name.
1946 */
1947 char month_name[4] = { 0 };
1948
1949 if (sscanf(ptr, "%d %3s%n",
1950 &tm.tm_mday,
1951 month_name,
1952 &num_chars) < 2)
1953 {
1954 /* Not matched. */
1955 goto fail;
1956 }
1957 if (!parse_month_name(month_name, &tm.tm_mon)) {
1958 goto fail;
1959 }
1960 ptr += num_chars;
1961 while (IS_WSP(*ptr)((*ptr) == ' ' || (*ptr) == '\t'))
1962 ptr++;
1963
1964 /*
1965 * Scan the year. Treat 2-digit years
1966 * differently from 4-digit years.
1967 */
1968 uint32_t year;
1969 const char *yearendp;
1970
1971 if (!ws_strtou32(ptr, &yearendp, &year)) {
1972 goto fail;
1973 }
1974 if (!IS_WSP(*yearendp)((*yearendp) == ' ' || (*yearendp) == '\t')) {
1975 /* Not followed by WSP. */
1976 goto fail;
1977 }
1978 if (yearendp - ptr < 2) {
1979 /* 1-digit year. Error. */
1980 goto fail;
1981 }
1982 if (yearendp - ptr == 2) {
1983 /*
1984 * 2-digit year.
1985 *
1986 * Match RFC 2822/RFC 5322 behavior;
1987 * add 2000 to years from 0 to
1988 * 49 and 1900 to uears from 50
1989 * to 99.
1990 */
1991 if (year <= 49) {
1992 year += 2000;
1993 } else {
1994 year += 1900;
1995 }
1996 } else if (yearendp - ptr == 3) {
1997 /*
1998 * 3-digit year.
1999 *
2000 * Match RFC 2822/RFC 5322 behavior;
2001 * add 1900 to the year.
2002 */
2003 year += 1900;
2004 }
2005 tm.tm_year = year - 1900;
2006 ptr = yearendp;
2007 while (IS_WSP(*ptr)((*ptr) == ' ' || (*ptr) == '\t'))
2008 ptr++;
2009
2010 /* Parse the time. */
2011 if (sscanf(ptr, "%d:%d%n:%d%n",
2012 &tm.tm_hour,
2013 &tm.tm_min,
2014 &num_chars,
2015 &tm.tm_sec,
2016 &num_chars) < 2)
2017 {
2018 goto fail;
2019 }
2020 ptr += num_chars;
2021 while (IS_WSP(*ptr)((*ptr) == ' ' || (*ptr) == '\t'))
2022 ptr++;
2023
2024 /*
2025 * Parse the time zone.
2026 * Check for obs-zone values first.
2027 */
2028 if (g_ascii_strncasecmp(ptr, "UT", 2) == 0)
2029 {
2030 ptr += 2;
2031 }
2032 else if (g_ascii_strncasecmp(ptr, "GMT", 3) == 0)
2033 {
2034 ptr += 3;
2035 }
2036 else
2037 {
2038 char sign;
2039 int off_hr;
2040 int off_min;
2041
2042 if (sscanf(ptr, "%c%2d%2d%n",
2043 &sign,
2044 &off_hr,
2045 &off_min,
2046 &num_chars) < 3)
2047 {
2048 goto fail;
2049 }
2050
2051 /*
2052 * If sign is '+', there's a positive
2053 * UTC offset.
2054 *
2055 * If sign is '-', there's a negative
2056 * UTC offset.
2057 *
2058 * Otherwise, that's an invalid UTC
2059 * offset string.
2060 */
2061 if (sign == '+')
2062 utc_offset += (off_hr * 3600) + (off_min * 60);
2063 else if (sign == '-')
2064 utc_offset -= (off_hr * 3600) + (off_min * 60);
2065 else {
2066 /* Sign must be + or - */
2067 goto fail;
2068 }
2069 ptr += num_chars;
2070 }
2071 end = ptr;
2072 }
2073 ns->secs = mktime_utc(&tm);
2074 if (ns->secs == (time_t)-1 && errno(*__errno_location ()) != 0) {
2075 goto fail;
2076 }
2077 ns->secs += utc_offset;
2078 }
2079 } else {
2080 /* Empty string */
2081 goto fail;
2082 }
2083
2084 if (endoff)
2085 *endoff = (int)(offset + (end - begin));
2086 wmem_free(NULL((void*)0), begin);
2087 return ns;
2088
2089fail:
2090 wmem_free(NULL((void*)0), begin);
2091 return NULL((void*)0);
2092}
2093
2094/* Fetch an IPv4 address, in network byte order.
2095 * We do *not* convert them to host byte order; we leave them in
2096 * network byte order. */
2097uint32_t
2098tvb_get_ipv4(tvbuff_t *tvb, const int offset)
2099{
2100 const uint8_t *ptr;
2101 uint32_t addr;
2102
2103 ptr = fast_ensure_contiguous(tvb, offset, sizeof(uint32_t));
2104 memcpy(&addr, ptr, sizeof addr);
2105 return addr;
2106}
2107
2108/* Fetch an IPv6 address. */
2109void
2110tvb_get_ipv6(tvbuff_t *tvb, const int offset, ws_in6_addr *addr)
2111{
2112 const uint8_t *ptr;
2113
2114 ptr = ensure_contiguous(tvb, offset, sizeof(*addr));
2115 memcpy(addr, ptr, sizeof *addr);
2116}
2117
2118/*
2119 * These routines return the length of the address in bytes on success
2120 * and -1 if the prefix length is too long.
2121 */
2122int
2123tvb_get_ipv4_addr_with_prefix_len(tvbuff_t *tvb, int offset, ws_in4_addr *addr,
2124 uint32_t prefix_len)
2125{
2126 uint8_t addr_len;
2127
2128 if (prefix_len > 32)
2129 return -1;
2130
2131 addr_len = (prefix_len + 7) / 8;
2132 *addr = 0;
2133 tvb_memcpy(tvb, addr, offset, addr_len);
2134 if (prefix_len % 8)
2135 ((uint8_t*)addr)[addr_len - 1] &= ((0xff00 >> (prefix_len % 8)) & 0xff);
2136 return addr_len;
2137}
2138
2139/*
2140 * These routines return the length of the address in bytes on success
2141 * and -1 if the prefix length is too long.
2142 */
2143int
2144tvb_get_ipv6_addr_with_prefix_len(tvbuff_t *tvb, int offset, ws_in6_addr *addr,
2145 uint32_t prefix_len)
2146{
2147 uint32_t addr_len;
2148
2149 if (prefix_len > 128)
2150 return -1;
2151
2152 addr_len = (prefix_len + 7) / 8;
2153 memset(addr->bytes, 0, 16);
2154 tvb_memcpy(tvb, addr->bytes, offset, addr_len);
2155 if (prefix_len % 8) {
2156 addr->bytes[addr_len - 1] &=
2157 ((0xff00 >> (prefix_len % 8)) & 0xff);
2158 }
2159
2160 return addr_len;
2161}
2162
2163/* Fetch a GUID. */
2164void
2165tvb_get_ntohguid(tvbuff_t *tvb, const int offset, e_guid_t *guid)
2166{
2167 const uint8_t *ptr = ensure_contiguous(tvb, offset, GUID_LEN16);
2168
2169 guid->data1 = pntohu32(ptr + 0);
2170 guid->data2 = pntohu16(ptr + 4);
2171 guid->data3 = pntohu16(ptr + 6);
2172 memcpy(guid->data4, ptr + 8, sizeof guid->data4);
2173}
2174
2175void
2176tvb_get_letohguid(tvbuff_t *tvb, const int offset, e_guid_t *guid)
2177{
2178 const uint8_t *ptr = ensure_contiguous(tvb, offset, GUID_LEN16);
2179
2180 guid->data1 = pletohu32(ptr + 0);
2181 guid->data2 = pletohu16(ptr + 4);
2182 guid->data3 = pletohu16(ptr + 6);
2183 memcpy(guid->data4, ptr + 8, sizeof guid->data4);
2184}
2185
2186void
2187tvb_get_guid(tvbuff_t *tvb, const int offset, e_guid_t *guid, const unsigned encoding)
2188{
2189 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
2190 tvb_get_letohguid(tvb, offset, guid);
2191 } else {
2192 tvb_get_ntohguid(tvb, offset, guid);
2193 }
2194}
2195
2196static const uint8_t bit_mask8[] = {
2197 0x00,
2198 0x01,
2199 0x03,
2200 0x07,
2201 0x0f,
2202 0x1f,
2203 0x3f,
2204 0x7f,
2205 0xff
2206};
2207
2208
2209/* Get a variable amount of bits
2210 *
2211 * Return a byte array with bit limited data.
2212 * When encoding is ENC_BIG_ENDIAN, the data is aligned to the left.
2213 * When encoding is ENC_LITTLE_ENDIAN, the data is aligned to the right.
2214 */
2215uint8_t *
2216tvb_get_bits_array(wmem_allocator_t *scope, tvbuff_t *tvb, const int bit_offset,
2217 size_t no_of_bits, size_t *data_length, const unsigned encoding)
2218{
2219 tvbuff_t *sub_tvb;
2220 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
1
Assuming the condition is true
2
Taking true branch
2221 sub_tvb = tvb_new_octet_right_aligned(tvb, bit_offset, (int32_t) no_of_bits);
3
Calling 'tvb_new_octet_right_aligned'
2222 } else {
2223 sub_tvb = tvb_new_octet_aligned(tvb, bit_offset, (int32_t) no_of_bits);
2224 }
2225 *data_length = tvb_reported_length(sub_tvb);
2226 return (uint8_t*)tvb_memdup(scope, sub_tvb, 0, *data_length);
2227}
2228
2229/* Get 1 - 8 bits */
2230uint8_t
2231tvb_get_bits8(tvbuff_t *tvb, unsigned bit_offset, const int no_of_bits)
2232{
2233 DISSECTOR_ASSERT_HINT(no_of_bits <= 8, "Too many bits requested for 8-bit return type")((void) ((no_of_bits <= 8) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\" (%s)", "epan/tvbuff.c", 2233
, "no_of_bits <= 8", "Too many bits requested for 8-bit return type"
))))
;
2234 return (uint8_t)_tvb_get_bits64(tvb, bit_offset, no_of_bits);
2235}
2236
2237/* Get 1 - 16 bits */
2238uint16_t
2239tvb_get_bits16(tvbuff_t *tvb, unsigned bit_offset, const int no_of_bits, const unsigned encoding)
2240{
2241 DISSECTOR_ASSERT_HINT(no_of_bits <= 16, "Too many bits requested for 16-bit return type")((void) ((no_of_bits <= 16) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\" (%s)", "epan/tvbuff.c", 2241
, "no_of_bits <= 16", "Too many bits requested for 16-bit return type"
))))
;
2242 return (uint16_t)tvb_get_bits64(tvb, bit_offset, no_of_bits, encoding);
2243}
2244
2245/* Get 1 - 32 bits */
2246uint32_t
2247tvb_get_bits32(tvbuff_t *tvb, unsigned bit_offset, const int no_of_bits, const unsigned encoding)
2248{
2249 DISSECTOR_ASSERT_HINT(no_of_bits <= 32, "Too many bits requested for 32-bit return type")((void) ((no_of_bits <= 32) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\" (%s)", "epan/tvbuff.c", 2249
, "no_of_bits <= 32", "Too many bits requested for 32-bit return type"
))))
;
2250 return (uint32_t)tvb_get_bits64(tvb, bit_offset, no_of_bits, encoding);
2251}
2252
2253/* Get 1 - 64 bits */
2254uint64_t
2255tvb_get_bits64(tvbuff_t *tvb, unsigned bit_offset, const int no_of_bits, const unsigned encoding)
2256{
2257 DISSECTOR_ASSERT_HINT(no_of_bits <= 64, "Too many bits requested for 64-bit return type")((void) ((no_of_bits <= 64) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\" (%s)", "epan/tvbuff.c", 2257
, "no_of_bits <= 64", "Too many bits requested for 64-bit return type"
))))
;
2258
2259 /* encoding determines bit numbering within octet array */
2260 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
2261 return _tvb_get_bits64_le(tvb, bit_offset, no_of_bits);
2262 } else {
2263 return _tvb_get_bits64(tvb, bit_offset, no_of_bits);
2264 }
2265}
2266
2267/*
2268 * This function will dissect a sequence of bits that does not need to be byte aligned; the bits
2269 * set will be shown in the tree as ..10 10.. and the integer value returned if return_value is set.
2270 * Offset should be given in bits from the start of the tvb.
2271 * Bits within octet are numbered from MSB (0) to LSB (7). Bit at bit_offset is return value most significant bit.
2272 * The function tolerates requests for more than 64 bits, but will only return the least significant 64 bits.
2273 */
2274static uint64_t
2275_tvb_get_bits64(tvbuff_t *tvb, unsigned bit_offset, const int total_no_of_bits)
2276{
2277 uint64_t value;
2278 unsigned octet_offset = bit_offset >> 3;
2279 uint8_t required_bits_in_first_octet = 8 - (bit_offset % 8);
2280
2281 if(required_bits_in_first_octet > total_no_of_bits)
2282 {
2283 /* the required bits don't extend to the end of the first octet */
2284 uint8_t right_shift = required_bits_in_first_octet - total_no_of_bits;
2285 value = (tvb_get_uint8(tvb, octet_offset) >> right_shift) & bit_mask8[total_no_of_bits % 8];
2286 }
2287 else
2288 {
2289 uint8_t remaining_bit_length = total_no_of_bits;
2290
2291 /* get the bits up to the first octet boundary */
2292 value = 0;
2293 required_bits_in_first_octet %= 8;
2294 if(required_bits_in_first_octet != 0)
2295 {
2296 value = tvb_get_uint8(tvb, octet_offset) & bit_mask8[required_bits_in_first_octet];
2297 remaining_bit_length -= required_bits_in_first_octet;
2298 octet_offset ++;
2299 }
2300 /* take the biggest words, shorts or octets that we can */
2301 while (remaining_bit_length > 7)
2302 {
2303 switch (remaining_bit_length >> 4)
2304 {
2305 case 0:
2306 /* 8 - 15 bits. (note that 0 - 7 would have dropped out of the while() loop) */
2307 value <<= 8;
2308 value += tvb_get_uint8(tvb, octet_offset);
2309 remaining_bit_length -= 8;
2310 octet_offset ++;
2311 break;
2312
2313 case 1:
2314 /* 16 - 31 bits */
2315 value <<= 16;
2316 value += tvb_get_ntohs(tvb, octet_offset);
2317 remaining_bit_length -= 16;
2318 octet_offset += 2;
2319 break;
2320
2321 case 2:
2322 case 3:
2323 /* 32 - 63 bits */
2324 value <<= 32;
2325 value += tvb_get_ntohl(tvb, octet_offset);
2326 remaining_bit_length -= 32;
2327 octet_offset += 4;
2328 break;
2329
2330 default:
2331 /* 64 bits (or more???) */
2332 value = tvb_get_ntoh64(tvb, octet_offset);
2333 remaining_bit_length -= 64;
2334 octet_offset += 8;
2335 break;
2336 }
2337 }
2338 /* get bits from any partial octet at the tail */
2339 if(remaining_bit_length)
2340 {
2341 value <<= remaining_bit_length;
2342 value += (tvb_get_uint8(tvb, octet_offset) >> (8 - remaining_bit_length));
2343 }
2344 }
2345 return value;
2346}
2347
2348/*
2349 * Offset should be given in bits from the start of the tvb.
2350 * Bits within octet are numbered from LSB (0) to MSB (7). Bit at bit_offset is return value least significant bit.
2351 * The function tolerates requests for more than 64 bits, but will only return the least significant 64 bits.
2352 */
2353static uint64_t
2354_tvb_get_bits64_le(tvbuff_t *tvb, unsigned bit_offset, const int total_no_of_bits)
2355{
2356 uint64_t value = 0;
2357 unsigned octet_offset = bit_offset / 8;
2358 int remaining_bits = total_no_of_bits;
2359 int shift = 0;
2360
2361 if (remaining_bits > 64)
2362 {
2363 remaining_bits = 64;
2364 }
2365
2366 if (bit_offset % 8)
2367 {
2368 /* not aligned, extract bits from first octet */
2369 shift = 8 - (bit_offset % 8);
2370 value = tvb_get_uint8(tvb, octet_offset) >> (bit_offset % 8);
2371 if (shift > remaining_bits)
2372 {
2373 /* keep only the requested bits */
2374 value &= (UINT64_C(1)1UL << remaining_bits) - 1;
2375 remaining_bits = 0;
2376 }
2377 else
2378 {
2379 remaining_bits -= shift;
2380 }
2381 octet_offset++;
2382 }
2383
2384 while (remaining_bits > 0)
2385 {
2386 /* take the biggest words, shorts or octets that we can */
2387 if (remaining_bits >= 32)
2388 {
2389 value |= ((uint64_t)tvb_get_letohl(tvb, octet_offset) << shift);
2390 shift += 32;
2391 remaining_bits -= 32;
2392 octet_offset += 4;
2393 }
2394 else if (remaining_bits >= 16)
2395 {
2396 value |= ((uint64_t)tvb_get_letohs(tvb, octet_offset) << shift);
2397 shift += 16;
2398 remaining_bits -= 16;
2399 octet_offset += 2;
2400 }
2401 else if (remaining_bits >= 8)
2402 {
2403 value |= ((uint64_t)tvb_get_uint8(tvb, octet_offset) << shift);
2404 shift += 8;
2405 remaining_bits -= 8;
2406 octet_offset += 1;
2407 }
2408 else
2409 {
2410 unsigned mask = (1 << remaining_bits) - 1;
2411 value |= (((uint64_t)tvb_get_uint8(tvb, octet_offset) & mask) << shift);
2412 shift += remaining_bits;
2413 remaining_bits = 0;
2414 octet_offset += 1;
2415 }
2416 }
2417 return value;
2418}
2419
2420/* Get 1 - 32 bits (should be deprecated as same as tvb_get_bits32??) */
2421uint32_t
2422tvb_get_bits(tvbuff_t *tvb, const unsigned bit_offset, const int no_of_bits, const unsigned encoding)
2423{
2424 return (uint32_t)tvb_get_bits64(tvb, bit_offset, no_of_bits, encoding);
2425}
2426
2427static int
2428tvb_find_uint8_generic(tvbuff_t *tvb, unsigned abs_offset, unsigned limit, uint8_t needle)
2429{
2430 const uint8_t *ptr;
2431 const uint8_t *result;
2432
2433 ptr = ensure_contiguous(tvb, abs_offset, limit); /* tvb_get_ptr() */
2434 if (!ptr)
2435 return -1;
2436
2437 result = (const uint8_t *) memchr(ptr, needle, limit);
2438 if (!result)
2439 return -1;
2440
2441 return (int) ((result - ptr) + abs_offset);
2442}
2443
2444/* Find first occurrence of needle in tvbuff, starting at offset. Searches
2445 * at most maxlength number of bytes; if maxlength is -1, searches to
2446 * end of tvbuff.
2447 * Returns the offset of the found needle, or -1 if not found.
2448 * Will not throw an exception, even if maxlength exceeds boundary of tvbuff;
2449 * in that case, -1 will be returned if the boundary is reached before
2450 * finding needle. */
2451int
2452tvb_find_uint8(tvbuff_t *tvb, const int offset, const int maxlength, const uint8_t needle)
2453{
2454 const uint8_t *result;
2455 unsigned abs_offset = 0;
2456 unsigned limit = 0;
2457 int exception;
2458
2459 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2459, "tvb && tvb->initialized"
))))
;
2460
2461 exception = compute_offset_and_remaining(tvb, offset, &abs_offset, &limit);
2462 if (exception)
2463 THROW(exception)except_throw(1, (exception), ((void*)0));
2464
2465 /* Only search to end of tvbuff, w/o throwing exception. */
2466 if (maxlength >= 0 && limit > (unsigned) maxlength) {
2467 /* Maximum length doesn't go past end of tvbuff; search
2468 to that value. */
2469 limit = (unsigned) maxlength;
2470 }
2471
2472 /* If we have real data, perform our search now. */
2473 if (tvb->real_data) {
2474 result = (const uint8_t *)memchr(tvb->real_data + abs_offset, needle, limit);
2475 if (result == NULL((void*)0)) {
2476 return -1;
2477 }
2478 else {
2479 return (int) (result - tvb->real_data);
2480 }
2481 }
2482
2483 if (tvb->ops->tvb_find_uint8)
2484 return tvb->ops->tvb_find_uint8(tvb, abs_offset, limit, needle);
2485
2486 return tvb_find_uint8_generic(tvb, offset, limit, needle);
2487}
2488
2489/* Same as tvb_find_uint8() with 16bit needle. */
2490int
2491tvb_find_uint16(tvbuff_t *tvb, const int offset, const int maxlength,
2492 const uint16_t needle)
2493{
2494 unsigned abs_offset = 0;
2495 unsigned limit = 0;
2496 int exception;
2497
2498 exception = compute_offset_and_remaining(tvb, offset, &abs_offset, &limit);
2499 if (exception)
2500 THROW(exception)except_throw(1, (exception), ((void*)0));
2501
2502 /* Only search to end of tvbuff, w/o throwing exception. */
2503 if (maxlength >= 0 && limit > (unsigned) maxlength) {
2504 /* Maximum length doesn't go past end of tvbuff; search
2505 to that value. */
2506 limit = (unsigned) maxlength;
2507 }
2508
2509 const uint8_t needle1 = ((needle & 0xFF00) >> 8);
2510 const uint8_t needle2 = ((needle & 0x00FF) >> 0);
2511 unsigned searched_bytes = 0;
2512 unsigned pos = abs_offset;
2513
2514 do {
2515 int offset1 =
2516 tvb_find_uint8(tvb, pos, limit - searched_bytes, needle1);
2517 int offset2 = -1;
2518
2519 if (offset1 == -1) {
2520 return -1;
2521 }
2522
2523 searched_bytes = (unsigned)offset1 - abs_offset + 1;
2524
2525 if (searched_bytes >= limit) {
2526 return -1;
2527 }
2528
2529 offset2 = tvb_find_uint8(tvb, offset1 + 1, 1, needle2);
2530
2531 searched_bytes += 1;
2532
2533 if (offset2 != -1) {
2534 if (searched_bytes > limit) {
2535 return -1;
2536 }
2537 return offset1;
2538 }
2539
2540 pos = offset1 + 1;
2541 } while (searched_bytes < limit);
2542
2543 return -1;
2544}
2545
2546static inline int
2547tvb_ws_mempbrk_uint8_generic(tvbuff_t *tvb, unsigned abs_offset, unsigned limit, const ws_mempbrk_pattern* pattern, unsigned char *found_needle)
2548{
2549 const uint8_t *ptr;
2550 const uint8_t *result;
2551
2552 ptr = ensure_contiguous(tvb, abs_offset, limit); /* tvb_get_ptr */
2553 if (!ptr)
2554 return -1;
2555
2556 result = ws_mempbrk_exec(ptr, limit, pattern, found_needle);
2557 if (!result)
2558 return -1;
2559
2560 return (int) ((result - ptr) + abs_offset);
2561}
2562
2563
2564/* Find first occurrence of any of the pattern chars in tvbuff, starting at offset.
2565 * Searches at most maxlength number of bytes; if maxlength is -1, searches
2566 * to end of tvbuff.
2567 * Returns the offset of the found needle, or -1 if not found.
2568 * Will not throw an exception, even if maxlength exceeds boundary of tvbuff;
2569 * in that case, -1 will be returned if the boundary is reached before
2570 * finding needle. */
2571int
2572tvb_ws_mempbrk_pattern_uint8(tvbuff_t *tvb, const int offset, const int maxlength,
2573 const ws_mempbrk_pattern* pattern, unsigned char *found_needle)
2574{
2575 const uint8_t *result;
2576 unsigned abs_offset = 0;
2577 unsigned limit = 0;
2578 int exception;
2579
2580 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2580, "tvb && tvb->initialized"
))))
;
2581
2582 exception = compute_offset_and_remaining(tvb, offset, &abs_offset, &limit);
2583 if (exception)
2584 THROW(exception)except_throw(1, (exception), ((void*)0));
2585
2586 /* Only search to end of tvbuff, w/o throwing exception. */
2587 if (limit > (unsigned) maxlength) {
2588 /* Maximum length doesn't go past end of tvbuff; search
2589 to that value. */
2590 limit = maxlength;
2591 }
2592
2593 /* If we have real data, perform our search now. */
2594 if (tvb->real_data) {
2595 result = ws_mempbrk_exec(tvb->real_data + abs_offset, limit, pattern, found_needle);
2596 if (result == NULL((void*)0)) {
2597 return -1;
2598 }
2599 else {
2600 return (int) (result - tvb->real_data);
2601 }
2602 }
2603
2604 if (tvb->ops->tvb_ws_mempbrk_pattern_uint8)
2605 return tvb->ops->tvb_ws_mempbrk_pattern_uint8(tvb, abs_offset, limit, pattern, found_needle);
2606
2607 return tvb_ws_mempbrk_uint8_generic(tvb, abs_offset, limit, pattern, found_needle);
2608}
2609
2610/* Find size of stringz (NUL-terminated string) by looking for terminating
2611 * NUL. The size of the string includes the terminating NUL.
2612 *
2613 * If the NUL isn't found, it throws the appropriate exception.
2614 */
2615unsigned
2616tvb_strsize(tvbuff_t *tvb, const int offset)
2617{
2618 unsigned abs_offset = 0, junk_length;
2619 int nul_offset;
2620
2621 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2621, "tvb && tvb->initialized"
))))
;
2622
2623 check_offset_length(tvb, offset, 0, &abs_offset, &junk_length);
2624 nul_offset = tvb_find_uint8(tvb, abs_offset, -1, 0);
2625 if (nul_offset == -1) {
2626 /*
2627 * OK, we hit the end of the tvbuff, so we should throw
2628 * an exception.
2629 */
2630 if (tvb->length < tvb->contained_length) {
2631 THROW(BoundsError)except_throw(1, (1), ((void*)0));
2632 } else if (tvb->flags & TVBUFF_FRAGMENT0x00000001) {
2633 THROW(FragmentBoundsError)except_throw(1, (4), ((void*)0));
2634 } else if (tvb->length < tvb->reported_length) {
2635 THROW(ContainedBoundsError)except_throw(1, (2), ((void*)0));
2636 } else {
2637 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
2638 }
2639 }
2640 return (nul_offset - abs_offset) + 1;
2641}
2642
2643/* UTF-16/UCS-2 version of tvb_strsize */
2644/* Returns number of bytes including the (two-bytes) null terminator */
2645unsigned
2646tvb_unicode_strsize(tvbuff_t *tvb, const int offset)
2647{
2648 unsigned i = 0;
2649 gunichar2 uchar;
2650
2651 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2651, "tvb && tvb->initialized"
))))
;
2652
2653 do {
2654 /* Endianness doesn't matter when looking for null */
2655 uchar = tvb_get_ntohs(tvb, offset + i);
2656 i += 2;
2657 } while(uchar != 0);
2658
2659 return i;
2660}
2661
2662/* Find length of string by looking for end of string ('\0'), up to
2663 * 'maxlength' characters'; if 'maxlength' is -1, searches to end
2664 * of tvbuff.
2665 * Returns -1 if 'maxlength' reached before finding EOS. */
2666int
2667tvb_strnlen(tvbuff_t *tvb, const int offset, const unsigned maxlength)
2668{
2669 int result_offset;
2670 unsigned abs_offset = 0, junk_length;
2671
2672 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2672, "tvb && tvb->initialized"
))))
;
2673
2674 check_offset_length(tvb, offset, 0, &abs_offset, &junk_length);
2675
2676 result_offset = tvb_find_uint8(tvb, abs_offset, maxlength, 0);
2677
2678 if (result_offset == -1) {
2679 return -1;
2680 }
2681 else {
2682 return result_offset - abs_offset;
2683 }
2684}
2685
2686/*
2687 * Implement strneql etc
2688 */
2689
2690/*
2691 * Call strncmp after checking if enough chars left, returning 0 if
2692 * it returns 0 (meaning "equal") and -1 otherwise, otherwise return -1.
2693 */
2694int
2695tvb_strneql(tvbuff_t *tvb, const int offset, const char *str, const size_t size)
2696{
2697 const uint8_t *ptr;
2698
2699 ptr = ensure_contiguous_no_exception(tvb, offset, (int)size, NULL((void*)0));
2700
2701 if (ptr) {
2702 int cmp = strncmp((const char *)ptr, str, size);
2703
2704 /*
2705 * Return 0 if equal, -1 otherwise.
2706 */
2707 return (cmp == 0 ? 0 : -1);
2708 } else {
2709 /*
2710 * Not enough characters in the tvbuff to match the
2711 * string.
2712 */
2713 return -1;
2714 }
2715}
2716
2717/*
2718 * Call g_ascii_strncasecmp after checking if enough chars left, returning
2719 * 0 if it returns 0 (meaning "equal") and -1 otherwise, otherwise return -1.
2720 */
2721int
2722tvb_strncaseeql(tvbuff_t *tvb, const int offset, const char *str, const size_t size)
2723{
2724 const uint8_t *ptr;
2725
2726 ptr = ensure_contiguous_no_exception(tvb, offset, (int)size, NULL((void*)0));
2727
2728 if (ptr) {
2729 int cmp = g_ascii_strncasecmp((const char *)ptr, str, size);
2730
2731 /*
2732 * Return 0 if equal, -1 otherwise.
2733 */
2734 return (cmp == 0 ? 0 : -1);
2735 } else {
2736 /*
2737 * Not enough characters in the tvbuff to match the
2738 * string.
2739 */
2740 return -1;
2741 }
2742}
2743
2744/*
2745 * Check that the tvbuff contains at least size bytes, starting at
2746 * offset, and that those bytes are equal to str. Return 0 for success
2747 * and -1 for error. This function does not throw an exception.
2748 */
2749int
2750tvb_memeql(tvbuff_t *tvb, const int offset, const uint8_t *str, size_t size)
2751{
2752 const uint8_t *ptr;
2753
2754 ptr = ensure_contiguous_no_exception(tvb, offset, (int) size, NULL((void*)0));
2755
2756 if (ptr) {
2757 int cmp = memcmp(ptr, str, size);
2758
2759 /*
2760 * Return 0 if equal, -1 otherwise.
2761 */
2762 return (cmp == 0 ? 0 : -1);
2763 } else {
2764 /*
2765 * Not enough characters in the tvbuff to match the
2766 * string.
2767 */
2768 return -1;
2769 }
2770}
2771
2772/**
2773 * Format the data in the tvb from offset for size.
2774 */
2775char *
2776tvb_format_text(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, const int size)
2777{
2778 const uint8_t *ptr;
2779 int len;
2780
2781 len = (size > 0) ? size : 0;
2782
2783 ptr = ensure_contiguous(tvb, offset, size);
2784 return format_text(scope, ptr, len);
2785}
2786
2787/*
2788 * Format the data in the tvb from offset for length ...
2789 */
2790char *
2791tvb_format_text_wsp(wmem_allocator_t* allocator, tvbuff_t *tvb, const int offset, const int size)
2792{
2793 const uint8_t *ptr;
2794 int len;
2795
2796 len = (size > 0) ? size : 0;
2797
2798 ptr = ensure_contiguous(tvb, offset, size);
2799 return format_text_wsp(allocator, ptr, len);
2800}
2801
2802/**
2803 * Like "tvb_format_text()", but for null-padded strings; don't show
2804 * the null padding characters as "\000".
2805 */
2806char *
2807tvb_format_stringzpad(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, const int size)
2808{
2809 const uint8_t *ptr, *p;
2810 int len;
2811 int stringlen;
2812
2813 len = (size > 0) ? size : 0;
2814
2815 ptr = ensure_contiguous(tvb, offset, size);
2816 for (p = ptr, stringlen = 0; stringlen < len && *p != '\0'; p++, stringlen++)
2817 ;
2818 return format_text(scope, ptr, stringlen);
2819}
2820
2821/*
2822 * Like "tvb_format_text_wsp()", but for null-padded strings; don't show
2823 * the null padding characters as "\000".
2824 */
2825char *
2826tvb_format_stringzpad_wsp(wmem_allocator_t* allocator, tvbuff_t *tvb, const int offset, const int size)
2827{
2828 const uint8_t *ptr, *p;
2829 int len;
2830 int stringlen;
2831
2832 len = (size > 0) ? size : 0;
2833
2834 ptr = ensure_contiguous(tvb, offset, size);
2835 for (p = ptr, stringlen = 0; stringlen < len && *p != '\0'; p++, stringlen++)
2836 ;
2837 return format_text_wsp(allocator, ptr, stringlen);
2838}
2839
2840/*
2841 * All string functions below take a scope as an argument.
2842 *
2843 *
2844 * If scope is NULL, memory is allocated with g_malloc() and user must
2845 * explicitly free it with g_free().
2846 * If scope is not NULL, memory is allocated with the corresponding pool
2847 * lifetime.
2848 *
2849 * All functions throw an exception if the tvbuff ends before the string
2850 * does.
2851 */
2852
2853/*
2854 * Given a wmem scope, a tvbuff, an offset, and a length, treat the string
2855 * of bytes referred to by the tvbuff, offset, and length as an ASCII string,
2856 * with all bytes with the high-order bit set being invalid, and return a
2857 * pointer to a UTF-8 string, allocated using the wmem scope.
2858 *
2859 * Octets with the highest bit set will be converted to the Unicode
2860 * REPLACEMENT CHARACTER.
2861 */
2862static uint8_t *
2863tvb_get_ascii_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length)
2864{
2865 const uint8_t *ptr;
2866
2867 ptr = ensure_contiguous(tvb, offset, length);
2868 return get_ascii_string(scope, ptr, length);
2869}
2870
2871/*
2872 * Given a wmem scope, a tvbuff, an offset, a length, and a translation table,
2873 * treat the string of bytes referred to by the tvbuff, offset, and length
2874 * as a string encoded using one octet per character, with octets with the
2875 * high-order bit clear being mapped by the translation table to 2-byte
2876 * Unicode Basic Multilingual Plane characters (including REPLACEMENT
2877 * CHARACTER) and octets with the high-order bit set being mapped to
2878 * REPLACEMENT CHARACTER, and return a pointer to a UTF-8 string,
2879 * allocated using the wmem scope.
2880 *
2881 * Octets with the highest bit set will be converted to the Unicode
2882 * REPLACEMENT CHARACTER.
2883 */
2884static uint8_t *
2885tvb_get_iso_646_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length, const gunichar2 table[0x80])
2886{
2887 const uint8_t *ptr;
2888
2889 ptr = ensure_contiguous(tvb, offset, length);
2890 return get_iso_646_string(scope, ptr, length, table);
2891}
2892
2893/*
2894 * Given a wmem scope, a tvbuff, an offset, and a length, treat the string
2895 * of bytes referred to by the tvbuff, the offset. and the length as a UTF-8
2896 * string, and return a pointer to a UTF-8 string, allocated using the wmem
2897 * scope, with all ill-formed sequences replaced with the Unicode REPLACEMENT
2898 * CHARACTER according to the recommended "best practices" given in the Unicode
2899 * Standard and specified by W3C/WHATWG.
2900 *
2901 * Note that in conformance with the Unicode Standard, this treats three
2902 * byte sequences corresponding to UTF-16 surrogate halves (paired or unpaired)
2903 * and two byte overlong encodings of 7-bit ASCII characters as invalid and
2904 * substitutes REPLACEMENT CHARACTER for them. Explicit support for nonstandard
2905 * derivative encoding formats (e.g. CESU-8, Java Modified UTF-8, WTF-8) could
2906 * be added later.
2907 */
2908static uint8_t *
2909tvb_get_utf_8_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, const int length)
2910{
2911 const uint8_t *ptr;
2912
2913 ptr = ensure_contiguous(tvb, offset, length);
2914 return get_utf_8_string(scope, ptr, length);
2915}
2916
2917/*
2918 * Given a wmem scope, a tvbuff, an offset, and a length, treat the string
2919 * of bytes referred to by the tvbuff, the offset, and the length as a
2920 * raw string, and return a pointer to that string, allocated using the
2921 * wmem scope. This means a null is appended at the end, but no replacement
2922 * checking is done otherwise, unlike tvb_get_utf_8_string().
2923 *
2924 * Also, this one allows a length of -1 to mean get all, but does not
2925 * allow a negative offset.
2926 */
2927static inline uint8_t *
2928tvb_get_raw_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, const int length)
2929{
2930 uint8_t *strbuf;
2931 int abs_length = length;
2932
2933 DISSECTOR_ASSERT(offset >= 0)((void) ((offset >= 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2933, "offset >= 0"
))))
;
2934 DISSECTOR_ASSERT(abs_length >= -1)((void) ((abs_length >= -1) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2934, "abs_length >= -1"
))))
;
2935
2936 if (abs_length < 0)
2937 abs_length = tvb->length - offset;
2938
2939 tvb_ensure_bytes_exist(tvb, offset, abs_length);
2940 strbuf = (uint8_t *)wmem_alloc(scope, abs_length + 1);
2941 tvb_memcpy(tvb, strbuf, offset, abs_length);
2942 strbuf[abs_length] = '\0';
2943 return strbuf;
2944}
2945
2946/*
2947 * Given a wmem scope, a tvbuff, an offset, and a length, treat the string
2948 * of bytes referred to by the tvbuff, the offset, and the length as an
2949 * ISO 8859/1 string, and return a pointer to a UTF-8 string, allocated
2950 * using the wmem scope.
2951 */
2952static uint8_t *
2953tvb_get_string_8859_1(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length)
2954{
2955 const uint8_t *ptr;
2956
2957 ptr = ensure_contiguous(tvb, offset, length);
2958 return get_8859_1_string(scope, ptr, length);
2959}
2960
2961/*
2962 * Given a wmem scope, a tvbuff, an offset, a length, and a translation
2963 * table, treat the string of bytes referred to by the tvbuff, the offset,
2964 * and the length as a string encoded using one octet per character, with
2965 * octets with the high-order bit clear being ASCII and octets with the
2966 * high-order bit set being mapped by the translation table to 2-byte
2967 * Unicode Basic Multilingual Plane characters (including REPLACEMENT
2968 * CHARACTER), and return a pointer to a UTF-8 string, allocated with the
2969 * wmem scope.
2970 */
2971static uint8_t *
2972tvb_get_string_unichar2(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length, const gunichar2 table[0x80])
2973{
2974 const uint8_t *ptr;
2975
2976 ptr = ensure_contiguous(tvb, offset, length);
2977 return get_unichar2_string(scope, ptr, length, table);
2978}
2979
2980/*
2981 * Given a wmem scope, a tvbuff, an offset, a length, and an encoding
2982 * giving the byte order, treat the string of bytes referred to by the
2983 * tvbuff, the offset, and the length as a UCS-2 encoded string in
2984 * the byte order in question, containing characters from the Basic
2985 * Multilingual Plane (plane 0) of Unicode, and return a pointer to a
2986 * UTF-8 string, allocated with the wmem scope.
2987 *
2988 * Encoding parameter should be ENC_BIG_ENDIAN or ENC_LITTLE_ENDIAN.
2989 *
2990 * Specify length in bytes.
2991 *
2992 * XXX - should map lead and trail surrogate values to REPLACEMENT
2993 * CHARACTERs (0xFFFD)?
2994 * XXX - if there are an odd number of bytes, should put a
2995 * REPLACEMENT CHARACTER at the end.
2996 */
2997static uint8_t *
2998tvb_get_ucs_2_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int length, const unsigned encoding)
2999{
3000 const uint8_t *ptr;
3001
3002 ptr = ensure_contiguous(tvb, offset, length);
3003 return get_ucs_2_string(scope, ptr, length, encoding);
3004}
3005
3006/*
3007 * Given a wmem scope, a tvbuff, an offset, a length, and an encoding
3008 * giving the byte order, treat the string of bytes referred to by the
3009 * tvbuff, the offset, and the length as a UTF-16 encoded string in
3010 * the byte order in question, and return a pointer to a UTF-8 string,
3011 * allocated with the wmem scope.
3012 *
3013 * Encoding parameter should be ENC_BIG_ENDIAN or ENC_LITTLE_ENDIAN.
3014 *
3015 * Specify length in bytes.
3016 *
3017 * XXX - should map surrogate errors to REPLACEMENT CHARACTERs (0xFFFD).
3018 * XXX - should map code points > 10FFFF to REPLACEMENT CHARACTERs.
3019 * XXX - if there are an odd number of bytes, should put a
3020 * REPLACEMENT CHARACTER at the end.
3021 */
3022static uint8_t *
3023tvb_get_utf_16_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int length, const unsigned encoding)
3024{
3025 const uint8_t *ptr;
3026
3027 ptr = ensure_contiguous(tvb, offset, length);
3028 return get_utf_16_string(scope, ptr, length, encoding);
3029}
3030
3031/*
3032 * Given a wmem scope, a tvbuff, an offset, a length, and an encoding
3033 * giving the byte order, treat the string of bytes referred to by the
3034 * tvbuff, the offset, and the length as a UCS-4 encoded string in
3035 * the byte order in question, and return a pointer to a UTF-8 string,
3036 * allocated with the wmem scope.
3037 *
3038 * Encoding parameter should be ENC_BIG_ENDIAN or ENC_LITTLE_ENDIAN
3039 *
3040 * Specify length in bytes
3041 *
3042 * XXX - should map lead and trail surrogate values to a "substitute"
3043 * UTF-8 character?
3044 * XXX - should map code points > 10FFFF to REPLACEMENT CHARACTERs.
3045 * XXX - if the number of bytes isn't a multiple of 4, should put a
3046 * REPLACEMENT CHARACTER at the end.
3047 */
3048static char *
3049tvb_get_ucs_4_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int length, const unsigned encoding)
3050{
3051 const uint8_t *ptr;
3052
3053 ptr = ensure_contiguous(tvb, offset, length);
3054 return get_ucs_4_string(scope, ptr, length, encoding);
3055}
3056
3057char *
3058tvb_get_ts_23_038_7bits_string_packed(wmem_allocator_t *scope, tvbuff_t *tvb,
3059 const int bit_offset, int no_of_chars)
3060{
3061 int in_offset = bit_offset >> 3; /* Current pointer to the input buffer */
3062 int length = ((no_of_chars + 1) * 7 + (bit_offset & 0x07)) >> 3;
3063 const uint8_t *ptr;
3064
3065 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 3065, "tvb && tvb->initialized"
))))
;
3066
3067 ptr = ensure_contiguous(tvb, in_offset, length);
3068 return get_ts_23_038_7bits_string_packed(scope, ptr, bit_offset, no_of_chars);
3069}
3070
3071char *
3072tvb_get_ts_23_038_7bits_string_unpacked(wmem_allocator_t *scope, tvbuff_t *tvb,
3073 const int offset, int length)
3074{
3075 const uint8_t *ptr;
3076
3077 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 3077, "tvb && tvb->initialized"
))))
;
3078
3079 ptr = ensure_contiguous(tvb, offset, length);
3080 return get_ts_23_038_7bits_string_unpacked(scope, ptr, length);
3081}
3082
3083char *
3084tvb_get_etsi_ts_102_221_annex_a_string(wmem_allocator_t *scope, tvbuff_t *tvb,
3085 const int offset, int length)
3086{
3087 const uint8_t *ptr;
3088
3089 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 3089, "tvb && tvb->initialized"
))))
;
3090
3091 ptr = ensure_contiguous(tvb, offset, length);
3092 return get_etsi_ts_102_221_annex_a_string(scope, ptr, length);
3093}
3094
3095char *
3096tvb_get_ascii_7bits_string(wmem_allocator_t *scope, tvbuff_t *tvb,
3097 const int bit_offset, int no_of_chars)
3098{
3099 int in_offset = bit_offset >> 3; /* Current pointer to the input buffer */
3100 int length = ((no_of_chars + 1) * 7 + (bit_offset & 0x07)) >> 3;
3101 const uint8_t *ptr;
3102
3103 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 3103, "tvb && tvb->initialized"
))))
;
3104
3105 ptr = ensure_contiguous(tvb, in_offset, length);
3106 return get_ascii_7bits_string(scope, ptr, bit_offset, no_of_chars);
3107}
3108
3109/*
3110 * Given a wmem scope, a tvbuff, an offset, a length, and a translation
3111 * table, treat the string of bytes referred to by the tvbuff, the offset,
3112 * and the length as a string encoded using one octet per character, with
3113 * octets being mapped by the translation table to 2-byte Unicode Basic
3114 * Multilingual Plane characters (including REPLACEMENT CHARACTER), and
3115 * return a pointer to a UTF-8 string, allocated with the wmem scope.
3116 */
3117static uint8_t *
3118tvb_get_nonascii_unichar2_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length, const gunichar2 table[256])
3119{
3120 const uint8_t *ptr;
3121
3122 ptr = ensure_contiguous(tvb, offset, length);
3123 return get_nonascii_unichar2_string(scope, ptr, length, table);
3124}
3125
3126/*
3127 * Given a wmem scope, a tvbuff, an offset, and a length, treat the bytes
3128 * referred to by the tvbuff, offset, and length as a GB18030 encoded string,
3129 * and return a pointer to a UTF-8 string, allocated with the wmem scope,
3130 * converted having substituted REPLACEMENT CHARACTER according to the
3131 * Unicode Standard 5.22 U+FFFD Substitution for Conversion.
3132 * ( https://www.unicode.org/versions/Unicode13.0.0/ch05.pdf )
3133 *
3134 * As expected, this will also decode GBK and GB2312 strings.
3135 */
3136static uint8_t *
3137tvb_get_gb18030_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length)
3138{
3139 const uint8_t *ptr;
3140
3141 ptr = ensure_contiguous(tvb, offset, length);
3142 return get_gb18030_string(scope, ptr, length);
3143}
3144
3145/*
3146 * Given a wmem scope, a tvbuff, an offset, and a length, treat the bytes
3147 * referred to by the tvbuff, offset, and length as a EUC-KR encoded string,
3148 * and return a pointer to a UTF-8 string, allocated with the wmem scope,
3149 * converted having substituted REPLACEMENT CHARACTER according to the
3150 * Unicode Standard 5.22 U+FFFD Substitution for Conversion.
3151 * ( https://www.unicode.org/versions/Unicode13.0.0/ch05.pdf )
3152 */
3153static uint8_t *
3154tvb_get_euc_kr_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length)
3155{
3156 const uint8_t *ptr;
3157
3158 ptr = ensure_contiguous(tvb, offset, length);
3159 return get_euc_kr_string(scope, ptr, length);
3160}
3161
3162static uint8_t *
3163tvb_get_t61_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length)
3164{
3165 const uint8_t *ptr;
3166
3167 ptr = ensure_contiguous(tvb, offset, length);
3168 return get_t61_string(scope, ptr, length);
3169}
3170
3171/*
3172 * Encoding tables for BCD strings.
3173 */
3174static const dgt_set_t Dgt0_9_bcd = {
3175 {
3176 /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
3177 '0','1','2','3','4','5','6','7','8','9','?','?','?','?','?','?'
3178 }
3179};
3180
3181static const dgt_set_t Dgt_keypad_abc_tbcd = {
3182 {
3183 /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
3184 '0','1','2','3','4','5','6','7','8','9','*','#','a','b','c','?'
3185 }
3186};
3187
3188static const dgt_set_t Dgt_ansi_tbcd = {
3189 {
3190 /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
3191 '0','1','2','3','4','5','6','7','8','9','?','B','C','*','#','?'
3192 }
3193};
3194
3195static const dgt_set_t Dgt_dect_standard_4bits_tbcd = {
3196 {
3197 /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
3198 '0','1','2','3','4','5','6','7','8','9','?',' ','?','?','?','?'
3199 }
3200};
3201
3202static uint8_t *
3203tvb_get_apn_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset,
3204 int length)
3205{
3206 wmem_strbuf_t *str;
3207
3208 /*
3209 * This is a domain name.
3210 *
3211 * 3GPP TS 23.003, section 19.4.2 "Fully Qualified Domain Names
3212 * (FQDNs)", subsection 19.4.2.1 "General", says:
3213 *
3214 * The encoding of any identifier used as part of a Fully
3215 * Qualifed Domain Name (FQDN) shall follow the Name Syntax
3216 * defined in IETF RFC 2181 [18], IETF RFC 1035 [19] and
3217 * IETF RFC 1123 [20]. An FQDN consists of one or more
3218 * labels. Each label is coded as a one octet length field
3219 * followed by that number of octets coded as 8 bit ASCII
3220 * characters.
3221 *
3222 * so this does not appear to use full-blown DNS compression -
3223 * the upper 2 bits of the length don't indicate that it's a
3224 * pointer or an extended label (RFC 2673).
3225 */
3226 str = wmem_strbuf_new_sized(scope, length + 1);
3227 if (length > 0) {
3228 const uint8_t *ptr;
3229
3230 ptr = ensure_contiguous(tvb, offset, length);
3231
3232 for (;;) {
3233 unsigned label_len;
3234
3235 /*
3236 * Process this label.
3237 */
3238 label_len = *ptr;
3239 ptr++;
3240 length--;
3241
3242 while (label_len != 0) {
3243 uint8_t ch;
3244
3245 if (length == 0)
3246 goto end;
3247
3248 ch = *ptr;
3249 if (ch < 0x80)
3250 wmem_strbuf_append_c(str, ch);
3251 else
3252 wmem_strbuf_append_unichar_repl(str)wmem_strbuf_append_unichar(str, 0x00FFFD);
3253 ptr++;
3254 label_len--;
3255 length--;
3256 }
3257
3258 if (length == 0)
3259 goto end;
3260
3261 wmem_strbuf_append_c(str, '.');
3262 }
3263 }
3264
3265end:
3266 return (uint8_t *) wmem_strbuf_finalize(str);
3267}
3268
3269static uint8_t *
3270tvb_get_dect_standard_8bits_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length)
3271{
3272 const uint8_t *ptr;
3273
3274 ptr = ensure_contiguous(tvb, offset, length);
3275 return get_dect_standard_8bits_string(scope, ptr, length);
3276}
3277
3278/*
3279 * Given a tvbuff, an offset, a length, and an encoding, allocate a
3280 * buffer big enough to hold a non-null-terminated string of that length
3281 * at that offset, plus a trailing '\0', copy into the buffer the
3282 * string as converted from the appropriate encoding to UTF-8, and
3283 * return a pointer to the string.
3284 */
3285uint8_t *
3286tvb_get_string_enc(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset,
3287 const int length, const unsigned encoding)
3288{
3289 uint8_t *strptr;
3290 bool_Bool odd, skip_first;
3291
3292 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 3292, "tvb && tvb->initialized"
))))
;
3293
3294 /* make sure length = -1 fails */
3295 if (length < 0) {
3296 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
3297 }
3298
3299 switch (encoding & ENC_CHARENCODING_MASK0x0000FFFE) {
3300
3301 case ENC_ASCII0x00000000:
3302 default:
3303 /*
3304 * For now, we treat bogus values as meaning
3305 * "ASCII" rather than reporting an error,
3306 * for the benefit of old dissectors written
3307 * when the last argument to proto_tree_add_item()
3308 * was a bool for the byte order, not an
3309 * encoding value, and passed non-zero values
3310 * other than true to mean "little-endian".
3311 */
3312 strptr = tvb_get_ascii_string(scope, tvb, offset, length);
3313 break;
3314
3315 case ENC_UTF_80x00000002:
3316 strptr = tvb_get_utf_8_string(scope, tvb, offset, length);
3317 break;
3318
3319 case ENC_UTF_160x00000004:
3320 strptr = tvb_get_utf_16_string(scope, tvb, offset, length,
3321 encoding & (ENC_LITTLE_ENDIAN0x80000000|ENC_BOM0x20000000));
3322 break;
3323
3324 case ENC_UCS_20x00000006:
3325 strptr = tvb_get_ucs_2_string(scope, tvb, offset, length,
3326 encoding & (ENC_LITTLE_ENDIAN0x80000000|ENC_BOM0x20000000));
3327 break;
3328
3329 case ENC_UCS_40x00000008:
3330 strptr = tvb_get_ucs_4_string(scope, tvb, offset, length,
3331 encoding & (ENC_LITTLE_ENDIAN0x80000000|ENC_BOM0x20000000));
3332 break;
3333
3334 case ENC_ISO_8859_10x0000000A:
3335 /*
3336 * ISO 8859-1 printable code point values are equal
3337 * to the equivalent Unicode code point value, so
3338 * no translation table is needed.
3339 */
3340 strptr = tvb_get_string_8859_1(scope, tvb, offset, length);
3341 break;
3342
3343 case ENC_ISO_8859_20x0000000C:
3344 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_2);
3345 break;
3346
3347 case ENC_ISO_8859_30x0000000E:
3348 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_3);
3349 break;
3350
3351 case ENC_ISO_8859_40x00000010:
3352 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_4);
3353 break;
3354
3355 case ENC_ISO_8859_50x00000012:
3356 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_5);
3357 break;
3358
3359 case ENC_ISO_8859_60x00000014:
3360 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_6);
3361 break;
3362
3363 case ENC_ISO_8859_70x00000016:
3364 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_7);
3365 break;
3366
3367 case ENC_ISO_8859_80x00000018:
3368 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_8);
3369 break;
3370
3371 case ENC_ISO_8859_90x0000001A:
3372 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_9);
3373 break;
3374
3375 case ENC_ISO_8859_100x0000001C:
3376 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_10);
3377 break;
3378
3379 case ENC_ISO_8859_110x0000001E:
3380 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_11);
3381 break;
3382
3383 case ENC_ISO_8859_130x00000022:
3384 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_13);
3385 break;
3386
3387 case ENC_ISO_8859_140x00000024:
3388 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_14);
3389 break;
3390
3391 case ENC_ISO_8859_150x00000026:
3392 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_15);
3393 break;
3394
3395 case ENC_ISO_8859_160x00000028:
3396 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_16);
3397 break;
3398
3399 case ENC_WINDOWS_12500x0000002A:
3400 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_cp1250);
3401 break;
3402
3403 case ENC_WINDOWS_12510x0000003C:
3404 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_cp1251);
3405 break;
3406
3407 case ENC_WINDOWS_12520x0000003A:
3408 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_cp1252);
3409 break;
3410
3411 case ENC_MAC_ROMAN0x00000030:
3412 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_mac_roman);
3413 break;
3414
3415 case ENC_CP4370x00000032:
3416 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_cp437);
3417 break;
3418
3419 case ENC_CP8550x0000003E:
3420 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_cp855);
3421 break;
3422
3423 case ENC_CP8660x00000040:
3424 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_cp866);
3425 break;
3426
3427 case ENC_ISO_646_BASIC0x00000042:
3428 strptr = tvb_get_iso_646_string(scope, tvb, offset, length, charset_table_iso_646_basic);
3429 break;
3430
3431 case ENC_3GPP_TS_23_038_7BITS_PACKED0x0000002C:
3432 {
3433 int bit_offset = offset << 3;
3434 int no_of_chars = (length << 3) / 7;
3435 strptr = tvb_get_ts_23_038_7bits_string_packed(scope, tvb, bit_offset, no_of_chars);
3436 }
3437 break;
3438
3439 case ENC_ASCII_7BITS0x00000034:
3440 {
3441 int bit_offset = offset << 3;
3442 int no_of_chars = (length << 3) / 7;
3443 strptr = tvb_get_ascii_7bits_string(scope, tvb, bit_offset, no_of_chars);
3444 }
3445 break;
3446
3447 case ENC_EBCDIC0x0000002E:
3448 /*
3449 * "Common" EBCDIC, covering all characters with the
3450 * same code point in all Roman-alphabet EBCDIC code
3451 * pages.
3452 */
3453 strptr = tvb_get_nonascii_unichar2_string(scope, tvb, offset, length, charset_table_ebcdic);
3454 break;
3455
3456 case ENC_EBCDIC_CP0370x00000038:
3457 /*
3458 * EBCDIC code page 037.
3459 */
3460 strptr = tvb_get_nonascii_unichar2_string(scope, tvb, offset, length, charset_table_ebcdic_cp037);
3461 break;
3462
3463 case ENC_EBCDIC_CP5000x00000060:
3464 /*
3465 * EBCDIC code page 500.
3466 */
3467 strptr = tvb_get_nonascii_unichar2_string(scope, tvb, offset, length, charset_table_ebcdic_cp500);
3468 break;
3469
3470 case ENC_T610x00000036:
3471 strptr = tvb_get_t61_string(scope, tvb, offset, length);
3472 break;
3473
3474 case ENC_BCD_DIGITS_0_90x00000044:
3475 /*
3476 * Packed BCD, with digits 0-9.
3477 */
3478 odd = (encoding & ENC_BCD_ODD_NUM_DIG0x00010000) >> 16;
3479 skip_first = (encoding & ENC_BCD_SKIP_FIRST0x00020000) >> 17;
3480 strptr = tvb_get_bcd_string(scope, tvb, offset, length, &Dgt0_9_bcd, skip_first, odd, !(encoding & ENC_LITTLE_ENDIAN0x80000000));
3481 break;
3482
3483 case ENC_KEYPAD_ABC_TBCD0x00000046:
3484 /*
3485 * Keypad-with-a/b/c "telephony BCD" - packed BCD, with
3486 * digits 0-9 and symbols *, #, a, b, and c.
3487 */
3488 odd = (encoding & ENC_BCD_ODD_NUM_DIG0x00010000) >> 16;
3489 skip_first = (encoding & ENC_BCD_SKIP_FIRST0x00020000) >> 17;
3490 strptr = tvb_get_bcd_string(scope, tvb, offset, length, &Dgt_keypad_abc_tbcd, skip_first, odd, !(encoding & ENC_LITTLE_ENDIAN0x80000000));
3491 break;
3492
3493 case ENC_KEYPAD_BC_TBCD0x00000048:
3494 /*
3495 * Keypad-with-B/C "telephony BCD" - packed BCD, with
3496 * digits 0-9 and symbols B, C, *, and #.
3497 */
3498 odd = (encoding & ENC_BCD_ODD_NUM_DIG0x00010000) >> 16;
3499 skip_first = (encoding & ENC_BCD_SKIP_FIRST0x00020000) >> 17;
3500 strptr = tvb_get_bcd_string(scope, tvb, offset, length, &Dgt_ansi_tbcd, skip_first, odd, !(encoding & ENC_LITTLE_ENDIAN0x80000000));
3501 break;
3502
3503 case ENC_3GPP_TS_23_038_7BITS_UNPACKED0x0000004C:
3504 strptr = tvb_get_ts_23_038_7bits_string_unpacked(scope, tvb, offset, length);
3505 break;
3506
3507 case ENC_ETSI_TS_102_221_ANNEX_A0x0000004E:
3508 strptr = tvb_get_etsi_ts_102_221_annex_a_string(scope, tvb, offset, length);
3509 break;
3510
3511 case ENC_GB180300x00000050:
3512 strptr = tvb_get_gb18030_string(scope, tvb, offset, length);
3513 break;
3514
3515 case ENC_EUC_KR0x00000052:
3516 strptr = tvb_get_euc_kr_string(scope, tvb, offset, length);
3517 break;
3518
3519 case ENC_APN_STR0x00000054:
3520 strptr = tvb_get_apn_string(scope, tvb, offset, length);
3521 break;
3522
3523 case ENC_DECT_STANDARD_8BITS0x00000056:
3524 strptr = tvb_get_dect_standard_8bits_string(scope, tvb, offset, length);
3525 break;
3526
3527 case ENC_DECT_STANDARD_4BITS_TBCD0x00000058:
3528 /*
3529 * DECT standard 4bits "telephony BCD" - packed BCD, with
3530 * digits 0-9 and symbol SPACE for 0xb.
3531 */
3532 odd = (encoding & ENC_BCD_ODD_NUM_DIG0x00010000) >> 16;
3533 skip_first = (encoding & ENC_BCD_SKIP_FIRST0x00020000) >> 17;
3534 strptr = tvb_get_bcd_string(scope, tvb, offset, length, &Dgt_dect_standard_4bits_tbcd, skip_first, odd, false0);
3535 break;
3536 }
3537 return strptr;
3538}
3539
3540/*
3541 * This is like tvb_get_string_enc(), except that it handles null-padded
3542 * strings.
3543 *
3544 * Currently, string values are stored as UTF-8 null-terminated strings,
3545 * so nothing needs to be done differently for null-padded strings; we
3546 * could save a little memory by not storing the null padding.
3547 *
3548 * If we ever store string values differently, in a fashion that doesn't
3549 * involve null termination, that might change.
3550 */
3551uint8_t *
3552tvb_get_stringzpad(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset,
3553 const int length, const unsigned encoding)
3554{
3555 return tvb_get_string_enc(scope, tvb, offset, length, encoding);
3556}
3557
3558/*
3559 * These routines are like the above routines, except that they handle
3560 * null-terminated strings. They find the length of that string (and
3561 * throw an exception if the tvbuff ends before we find the null), and
3562 * also return through a pointer the length of the string, in bytes,
3563 * including the terminating null (the terminating null being 2 bytes
3564 * for UCS-2 and UTF-16, 4 bytes for UCS-4, and 1 byte for other
3565 * encodings).
3566 */
3567static uint8_t *
3568tvb_get_ascii_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp)
3569{
3570 unsigned size;
3571 const uint8_t *ptr;
3572
3573 size = tvb_strsize(tvb, offset);
3574 ptr = ensure_contiguous(tvb, offset, size);
3575 /* XXX, conversion between signed/unsigned integer */
3576 if (lengthp)
3577 *lengthp = size;
3578 return get_ascii_string(scope, ptr, size);
3579}
3580
3581static uint8_t *
3582tvb_get_iso_646_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp, const gunichar2 table[0x80])
3583{
3584 unsigned size;
3585 const uint8_t *ptr;
3586
3587 size = tvb_strsize(tvb, offset);
3588 ptr = ensure_contiguous(tvb, offset, size);
3589 /* XXX, conversion between signed/unsigned integer */
3590 if (lengthp)
3591 *lengthp = size;
3592 return get_iso_646_string(scope, ptr, size, table);
3593}
3594
3595static uint8_t *
3596tvb_get_utf_8_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int *lengthp)
3597{
3598 unsigned size;
3599 const uint8_t *ptr;
3600
3601 size = tvb_strsize(tvb, offset);
3602 ptr = ensure_contiguous(tvb, offset, size);
3603 /* XXX, conversion between signed/unsigned integer */
3604 if (lengthp)
3605 *lengthp = size;
3606 return get_utf_8_string(scope, ptr, size);
3607}
3608
3609static uint8_t *
3610tvb_get_stringz_8859_1(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp)
3611{
3612 unsigned size;
3613 const uint8_t *ptr;
3614
3615 size = tvb_strsize(tvb, offset);
3616 ptr = ensure_contiguous(tvb, offset, size);
3617 /* XXX, conversion between signed/unsigned integer */
3618 if (lengthp)
3619 *lengthp = size;
3620 return get_8859_1_string(scope, ptr, size);
3621}
3622
3623static uint8_t *
3624tvb_get_stringz_unichar2(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp, const gunichar2 table[0x80])
3625{
3626 unsigned size;
3627 const uint8_t *ptr;
3628
3629 size = tvb_strsize(tvb, offset);
3630 ptr = ensure_contiguous(tvb, offset, size);
3631 /* XXX, conversion between signed/unsigned integer */
3632 if (lengthp)
3633 *lengthp = size;
3634 return get_unichar2_string(scope, ptr, size, table);
3635}
3636
3637/*
3638 * Given a tvbuff and an offset, with the offset assumed to refer to
3639 * a null-terminated string, find the length of that string (and throw
3640 * an exception if the tvbuff ends before we find the null), ensure that
3641 * the TVB is flat, and return a pointer to the string (in the TVB).
3642 * Also return the length of the string (including the terminating null)
3643 * through a pointer.
3644 *
3645 * As long as we aren't using composite TVBs, this saves the cycles used
3646 * (often unnecessariliy) in allocating a buffer and copying the string into
3647 * it. (If we do start using composite TVBs, we may want to replace this
3648 * function with the _ephemeral version.)
3649 */
3650const uint8_t *
3651tvb_get_const_stringz(tvbuff_t *tvb, const int offset, int *lengthp)
3652{
3653 unsigned size;
3654 const uint8_t *strptr;
3655
3656 size = tvb_strsize(tvb, offset);
3657 strptr = ensure_contiguous(tvb, offset, size);
3658 if (lengthp)
3659 *lengthp = size;
3660 return strptr;
3661}
3662
3663static char *
3664tvb_get_ucs_2_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int *lengthp, const unsigned encoding)
3665{
3666 int size; /* Number of bytes in string */
3667 const uint8_t *ptr;
3668
3669 size = tvb_unicode_strsize(tvb, offset);
3670 ptr = ensure_contiguous(tvb, offset, size);
3671 /* XXX, conversion between signed/unsigned integer */
3672 if (lengthp)
3673 *lengthp = size;
3674 return get_ucs_2_string(scope, ptr, size, encoding);
3675}
3676
3677static char *
3678tvb_get_utf_16_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int *lengthp, const unsigned encoding)
3679{
3680 int size;
3681 const uint8_t *ptr;
3682
3683 size = tvb_unicode_strsize(tvb, offset);
3684 ptr = ensure_contiguous(tvb, offset, size);
3685 /* XXX, conversion between signed/unsigned integer */
3686 if (lengthp)
3687 *lengthp = size;
3688 return get_utf_16_string(scope, ptr, size, encoding);
3689}
3690
3691static char *
3692tvb_get_ucs_4_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int *lengthp, const unsigned encoding)
3693{
3694 int size;
3695 gunichar uchar;
3696 const uint8_t *ptr;
3697
3698 size = 0;
3699 do {
3700 /* Endianness doesn't matter when looking for null */
3701 uchar = tvb_get_ntohl(tvb, offset + size);
3702 size += 4;
3703 } while(uchar != 0);
3704
3705 ptr = ensure_contiguous(tvb, offset, size);
3706 /* XXX, conversion between signed/unsigned integer */
3707 if (lengthp)
3708 *lengthp = size;
3709 return get_ucs_4_string(scope, ptr, size, encoding);
3710}
3711
3712static uint8_t *
3713tvb_get_nonascii_unichar2_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp, const gunichar2 table[256])
3714{
3715 unsigned size;
3716 const uint8_t *ptr;
3717
3718 size = tvb_strsize(tvb, offset);
3719 ptr = ensure_contiguous(tvb, offset, size);
3720 /* XXX, conversion between signed/unsigned integer */
3721 if (lengthp)
3722 *lengthp = size;
3723 return get_nonascii_unichar2_string(scope, ptr, size, table);
3724}
3725
3726static uint8_t *
3727tvb_get_t61_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp)
3728{
3729 unsigned size;
3730 const uint8_t *ptr;
3731
3732 size = tvb_strsize(tvb, offset);
3733 ptr = ensure_contiguous(tvb, offset, size);
3734 /* XXX, conversion between signed/unsigned integer */
3735 if (lengthp)
3736 *lengthp = size;
3737 return get_t61_string(scope, ptr, size);
3738}
3739
3740static uint8_t *
3741tvb_get_gb18030_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp)
3742{
3743 unsigned size;
3744 const uint8_t *ptr;
3745
3746 size = tvb_strsize(tvb, offset);
3747 ptr = ensure_contiguous(tvb, offset, size);
3748 /* XXX, conversion between signed/unsigned integer */
3749 if (lengthp)
3750 *lengthp = size;
3751 return get_gb18030_string(scope, ptr, size);
3752}
3753
3754static uint8_t *
3755tvb_get_euc_kr_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp)
3756{
3757 unsigned size;
3758 const uint8_t *ptr;
3759
3760 size = tvb_strsize(tvb, offset);
3761 ptr = ensure_contiguous(tvb, offset, size);
3762 /* XXX, conversion between signed/unsigned integer */
3763 if (lengthp)
3764 *lengthp = size;
3765 return get_euc_kr_string(scope, ptr, size);
3766}
3767
3768static uint8_t *
3769tvb_get_dect_standard_8bits_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp)
3770{
3771 unsigned size;
3772 const uint8_t *ptr;
3773
3774 size = tvb_strsize(tvb, offset);
3775 ptr = ensure_contiguous(tvb, offset, size);
3776 /* XXX, conversion between signed/unsigned integer */
3777 if (lengthp)
3778 *lengthp = size;
3779 return get_dect_standard_8bits_string(scope, ptr, size);
3780}
3781
3782uint8_t *
3783tvb_get_stringz_enc(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int *lengthp, const unsigned encoding)
3784{
3785 uint8_t *strptr;
3786
3787 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 3787, "tvb && tvb->initialized"
))))
;
3788
3789 switch (encoding & ENC_CHARENCODING_MASK0x0000FFFE) {
3790
3791 case ENC_ASCII0x00000000:
3792 default:
3793 /*
3794 * For now, we treat bogus values as meaning
3795 * "ASCII" rather than reporting an error,
3796 * for the benefit of old dissectors written
3797 * when the last argument to proto_tree_add_item()
3798 * was a bool for the byte order, not an
3799 * encoding value, and passed non-zero values
3800 * other than true to mean "little-endian".
3801 */
3802 strptr = tvb_get_ascii_stringz(scope, tvb, offset, lengthp);
3803 break;
3804
3805 case ENC_UTF_80x00000002:
3806 /*
3807 * XXX - should map all invalid UTF-8 sequences
3808 * to a "substitute" UTF-8 character.
3809 * XXX - should map code points > 10FFFF to REPLACEMENT
3810 * CHARACTERs.
3811 */
3812 strptr = tvb_get_utf_8_stringz(scope, tvb, offset, lengthp);
3813 break;
3814
3815 case ENC_UTF_160x00000004:
3816 strptr = tvb_get_utf_16_stringz(scope, tvb, offset, lengthp,
3817 encoding & (ENC_LITTLE_ENDIAN0x80000000|ENC_BOM0x20000000));
3818 break;
3819
3820 case ENC_UCS_20x00000006:
3821 strptr = tvb_get_ucs_2_stringz(scope, tvb, offset, lengthp,
3822 encoding & (ENC_LITTLE_ENDIAN0x80000000|ENC_BOM0x20000000));
3823 break;
3824
3825 case ENC_UCS_40x00000008:
3826 strptr = tvb_get_ucs_4_stringz(scope, tvb, offset, lengthp,
3827 encoding & (ENC_LITTLE_ENDIAN0x80000000|ENC_BOM0x20000000));
3828 break;
3829
3830 case ENC_ISO_8859_10x0000000A:
3831 /*
3832 * ISO 8859-1 printable code point values are equal
3833 * to the equivalent Unicode code point value, so
3834 * no translation table is needed.
3835 */
3836 strptr = tvb_get_stringz_8859_1(scope, tvb, offset, lengthp);
3837 break;
3838
3839 case ENC_ISO_8859_20x0000000C:
3840 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_2);
3841 break;
3842
3843 case ENC_ISO_8859_30x0000000E:
3844 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_3);
3845 break;
3846
3847 case ENC_ISO_8859_40x00000010:
3848 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_4);
3849 break;
3850
3851 case ENC_ISO_8859_50x00000012:
3852 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_5);
3853 break;
3854
3855 case ENC_ISO_8859_60x00000014:
3856 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_6);
3857 break;
3858
3859 case ENC_ISO_8859_70x00000016:
3860 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_7);
3861 break;
3862
3863 case ENC_ISO_8859_80x00000018:
3864 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_8);
3865 break;
3866
3867 case ENC_ISO_8859_90x0000001A:
3868 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_9);
3869 break;
3870
3871 case ENC_ISO_8859_100x0000001C:
3872 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_10);
3873 break;
3874
3875 case ENC_ISO_8859_110x0000001E:
3876 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_11);
3877 break;
3878
3879 case ENC_ISO_8859_130x00000022:
3880 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_13);
3881 break;
3882
3883 case ENC_ISO_8859_140x00000024:
3884 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_14);
3885 break;
3886
3887 case ENC_ISO_8859_150x00000026:
3888 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_15);
3889 break;
3890
3891 case ENC_ISO_8859_160x00000028:
3892 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_16);
3893 break;
3894
3895 case ENC_WINDOWS_12500x0000002A:
3896 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_cp1250);
3897 break;
3898
3899 case ENC_WINDOWS_12510x0000003C:
3900 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_cp1251);
3901 break;
3902
3903 case ENC_WINDOWS_12520x0000003A:
3904 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_cp1252);
3905 break;
3906
3907 case ENC_MAC_ROMAN0x00000030:
3908 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_mac_roman);
3909 break;
3910
3911 case ENC_CP4370x00000032:
3912 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_cp437);
3913 break;
3914
3915 case ENC_CP8550x0000003E:
3916 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_cp855);
3917 break;
3918
3919 case ENC_CP8660x00000040:
3920 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_cp866);
3921 break;
3922
3923 case ENC_ISO_646_BASIC0x00000042:
3924 strptr = tvb_get_iso_646_stringz(scope, tvb, offset, lengthp, charset_table_iso_646_basic);
3925 break;
3926
3927 case ENC_3GPP_TS_23_038_7BITS_PACKED0x0000002C:
3928 case ENC_3GPP_TS_23_038_7BITS_UNPACKED0x0000004C:
3929 case ENC_ETSI_TS_102_221_ANNEX_A0x0000004E:
3930 REPORT_DISSECTOR_BUG("TS 23.038 7bits has no null character and doesn't support null-terminated strings")proto_report_dissector_bug("TS 23.038 7bits has no null character and doesn't support null-terminated strings"
)
;
3931 break;
3932
3933 case ENC_ASCII_7BITS0x00000034:
3934 REPORT_DISSECTOR_BUG("tvb_get_stringz_enc function with ENC_ASCII_7BITS not implemented yet")proto_report_dissector_bug("tvb_get_stringz_enc function with ENC_ASCII_7BITS not implemented yet"
)
;
3935 break;
3936
3937 case ENC_EBCDIC0x0000002E:
3938 /*
3939 * "Common" EBCDIC, covering all characters with the
3940 * same code point in all Roman-alphabet EBCDIC code
3941 * pages.
3942 */
3943 strptr = tvb_get_nonascii_unichar2_stringz(scope, tvb, offset, lengthp, charset_table_ebcdic);
3944 break;
3945
3946 case ENC_EBCDIC_CP0370x00000038:
3947 /*
3948 * EBCDIC code page 037.
3949 */
3950 strptr = tvb_get_nonascii_unichar2_stringz(scope, tvb, offset, lengthp, charset_table_ebcdic_cp037);
3951 break;
3952
3953 case ENC_EBCDIC_CP5000x00000060:
3954 /*
3955 * EBCDIC code page 500.
3956 */
3957 strptr = tvb_get_nonascii_unichar2_stringz(scope, tvb, offset, lengthp, charset_table_ebcdic_cp500);
3958 break;
3959
3960 case ENC_T610x00000036:
3961 strptr = tvb_get_t61_stringz(scope, tvb, offset, lengthp);
3962 break;
3963
3964 case ENC_GB180300x00000050:
3965 strptr = tvb_get_gb18030_stringz(scope, tvb, offset, lengthp);
3966 break;
3967
3968 case ENC_EUC_KR0x00000052:
3969 strptr = tvb_get_euc_kr_stringz(scope, tvb, offset, lengthp);
3970 break;
3971
3972 case ENC_DECT_STANDARD_8BITS0x00000056:
3973 strptr = tvb_get_dect_standard_8bits_stringz(scope, tvb, offset, lengthp);
3974 break;
3975 }
3976
3977 return strptr;
3978}
3979
3980/* Looks for a stringz (NUL-terminated string) in tvbuff and copies
3981 * no more than bufsize number of bytes, including terminating NUL, to buffer.
3982 * Returns length of string (not including terminating NUL), or -1 if the string was
3983 * truncated in the buffer due to not having reached the terminating NUL.
3984 * In this way, it acts like snprintf().
3985 *
3986 * bufsize MUST be greater than 0.
3987 *
3988 * When processing a packet where the remaining number of bytes is less
3989 * than bufsize, an exception is not thrown if the end of the packet
3990 * is reached before the NUL is found. If no NUL is found before reaching
3991 * the end of the short packet, -1 is still returned, and the string
3992 * is truncated with a NUL, albeit not at buffer[bufsize - 1], but
3993 * at the correct spot, terminating the string.
3994 *
3995 * *bytes_copied will contain the number of bytes actually copied,
3996 * including the terminating-NUL.
3997 */
3998static int
3999_tvb_get_raw_bytes_as_stringz(tvbuff_t *tvb, const int offset, const unsigned bufsize, uint8_t* buffer, int *bytes_copied)
4000{
4001 int stringlen;
4002 unsigned abs_offset = 0;
4003 int limit, len = 0;
4004 bool_Bool decreased_max = false0;
4005
4006 /* Only read to end of tvbuff, w/o throwing exception. */
4007 check_offset_length(tvb, offset, -1, &abs_offset, &len);
4008
4009 /* There must at least be room for the terminating NUL. */
4010 DISSECTOR_ASSERT(bufsize != 0)((void) ((bufsize != 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4010, "bufsize != 0"
))))
;
4011
4012 /* If there's no room for anything else, just return the NUL. */
4013 if (bufsize == 1) {
4014 buffer[0] = 0;
4015 *bytes_copied = 1;
4016 return 0;
4017 }
4018
4019 /* check_offset_length() won't throw an exception if we're
4020 * looking at the byte immediately after the end of the tvbuff. */
4021 if (len == 0) {
4022 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
4023 }
4024
4025 /* This should not happen because check_offset_length() would
4026 * have already thrown an exception if 'offset' were out-of-bounds.
4027 */
4028 DISSECTOR_ASSERT(len != -1)((void) ((len != -1) ? (void)0 : (proto_report_dissector_bug(
"%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4028, "len != -1"
))))
;
4029
4030 /*
4031 * If we've been passed a negative number, bufsize will
4032 * be huge.
4033 */
4034 DISSECTOR_ASSERT(bufsize <= INT_MAX)((void) ((bufsize <= 2147483647) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4034, "bufsize <= 2147483647"
))))
;
4035
4036 if ((unsigned)len < bufsize) {
4037 limit = len;
4038 decreased_max = true1;
4039 }
4040 else {
4041 limit = bufsize;
4042 }
4043
4044 stringlen = tvb_strnlen(tvb, abs_offset, limit - 1);
4045 /* If NUL wasn't found, copy the data and return -1 */
4046 if (stringlen == -1) {
4047 tvb_memcpy(tvb, buffer, abs_offset, limit);
4048 if (decreased_max) {
4049 buffer[limit] = 0;
4050 /* Add 1 for the extra NUL that we set at buffer[limit],
4051 * pretending that it was copied as part of the string. */
4052 *bytes_copied = limit + 1;
4053 }
4054 else {
4055 *bytes_copied = limit;
4056 }
4057 return -1;
4058 }
4059
4060 /* Copy the string to buffer */
4061 tvb_memcpy(tvb, buffer, abs_offset, stringlen + 1);
4062 *bytes_copied = stringlen + 1;
4063 return stringlen;
4064}
4065
4066int
4067tvb_get_raw_bytes_as_stringz(tvbuff_t *tvb, const int offset, const unsigned bufsize, uint8_t* buffer)
4068{
4069 int len, bytes_copied;
4070
4071 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4071, "tvb && tvb->initialized"
))))
;
4072
4073 len = _tvb_get_raw_bytes_as_stringz(tvb, offset, bufsize, buffer, &bytes_copied);
4074
4075 if (len == -1) {
4076 buffer[bufsize - 1] = 0;
4077 return bytes_copied - 1;
4078 }
4079 else {
4080 return len;
4081 }
4082}
4083
4084/*
4085 * Given a tvbuff, an offset into the tvbuff, a buffer, and a buffer size,
4086 * extract as many raw bytes from the tvbuff, starting at the offset,
4087 * as 1) are available in the tvbuff and 2) will fit in the buffer, leaving
4088 * room for a terminating NUL.
4089 */
4090int
4091tvb_get_raw_bytes_as_string(tvbuff_t *tvb, const int offset, char *buffer, size_t bufsize)
4092{
4093 int len = 0;
4094
4095 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4095, "tvb && tvb->initialized"
))))
;
4096
4097 /* There must be room for the string and the terminating NUL. */
4098 DISSECTOR_ASSERT(bufsize > 0)((void) ((bufsize > 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4098, "bufsize > 0"
))))
;
4099
4100 DISSECTOR_ASSERT(bufsize - 1 < INT_MAX)((void) ((bufsize - 1 < 2147483647) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4100, "bufsize - 1 < 2147483647"
))))
;
4101
4102 len = tvb_captured_length_remaining(tvb, offset);
4103 if (len <= 0) {
4104 buffer[0] = '\0';
4105 return 0;
4106 }
4107 if (len > (int)(bufsize - 1))
4108 len = (int)(bufsize - 1);
4109
4110 /* Copy the string to buffer */
4111 tvb_memcpy(tvb, buffer, offset, len);
4112 buffer[len] = '\0';
4113 return len;
4114}
4115
4116bool_Bool
4117tvb_ascii_isprint(tvbuff_t *tvb, const int offset, const int length)
4118{
4119 const uint8_t* buf = tvb_get_ptr(tvb, offset, length);
4120 unsigned abs_offset, abs_length = length;
4121
4122 if (length == -1) {
4123 /* tvb_get_ptr has already checked for exceptions. */
4124 compute_offset_and_remaining(tvb, offset, &abs_offset, &abs_length);
4125 }
4126 for (unsigned i = 0; i < abs_length; i++, buf++)
4127 if (!g_ascii_isprint(*buf)((g_ascii_table[(guchar) (*buf)] & G_ASCII_PRINT) != 0))
4128 return false0;
4129
4130 return true1;
4131}
4132
4133bool_Bool
4134tvb_utf_8_isprint(tvbuff_t *tvb, const int offset, const int length)
4135{
4136 const uint8_t* buf = tvb_get_ptr(tvb, offset, length);
4137 unsigned abs_offset, abs_length = length;
4138
4139 if (length == -1) {
4140 /* tvb_get_ptr has already checked for exceptions. */
4141 compute_offset_and_remaining(tvb, offset, &abs_offset, &abs_length);
4142 }
4143
4144 return isprint_utf8_string(buf, abs_length);
4145}
4146
4147bool_Bool
4148tvb_ascii_isdigit(tvbuff_t *tvb, const int offset, const int length)
4149{
4150 const uint8_t* buf = tvb_get_ptr(tvb, offset, length);
4151 unsigned abs_offset, abs_length = length;
4152
4153 if (length == -1) {
4154 /* tvb_get_ptr has already checked for exceptions. */
4155 compute_offset_and_remaining(tvb, offset, &abs_offset, &abs_length);
4156 }
4157 for (unsigned i = 0; i < abs_length; i++, buf++)
4158 if (!g_ascii_isdigit(*buf)((g_ascii_table[(guchar) (*buf)] & G_ASCII_DIGIT) != 0))
4159 return false0;
4160
4161 return true1;
4162}
4163
4164static ws_mempbrk_pattern pbrk_crlf;
4165/*
4166 * Given a tvbuff, an offset into the tvbuff, and a length that starts
4167 * at that offset (which may be -1 for "all the way to the end of the
4168 * tvbuff"), find the end of the (putative) line that starts at the
4169 * specified offset in the tvbuff, going no further than the specified
4170 * length.
4171 *
4172 * Return the length of the line (not counting the line terminator at
4173 * the end), or, if we don't find a line terminator:
4174 *
4175 * if "desegment" is true, return -1;
4176 *
4177 * if "desegment" is false, return the amount of data remaining in
4178 * the buffer.
4179 *
4180 * If "next_offset" is not NULL, set "*next_offset" to the offset of the
4181 * character past the line terminator, or past the end of the buffer if
4182 * we don't find a line terminator. (It's not set if we return -1.)
4183 */
4184int
4185tvb_find_line_end(tvbuff_t *tvb, const int offset, int len, int *next_offset, const bool_Bool desegment)
4186{
4187 int eob_offset;
4188 int eol_offset;
4189 int linelen;
4190 unsigned char found_needle = 0;
4191 static bool_Bool compiled = false0;
4192
4193 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4193, "tvb && tvb->initialized"
))))
;
4194
4195 if (len == -1) {
4196 len = _tvb_captured_length_remaining(tvb, offset);
4197 /* if offset is past the end of the tvbuff, len is now 0 */
4198 }
4199
4200 eob_offset = offset + len;
4201
4202 if (!compiled) {
4203 ws_mempbrk_compile(&pbrk_crlf, "\r\n");
4204 compiled = true1;
4205 }
4206
4207 /*
4208 * Look either for a CR or an LF.
4209 */
4210 eol_offset = tvb_ws_mempbrk_pattern_uint8(tvb, offset, len, &pbrk_crlf, &found_needle);
4211 if (eol_offset == -1) {
4212 /*
4213 * No CR or LF - line is presumably continued in next packet.
4214 */
4215 if (desegment) {
4216 /*
4217 * Tell our caller we saw no EOL, so they can
4218 * try to desegment and get the entire line
4219 * into one tvbuff.
4220 */
4221 return -1;
4222 } else {
4223 /*
4224 * Pretend the line runs to the end of the tvbuff.
4225 */
4226 linelen = eob_offset - offset;
4227 if (next_offset)
4228 *next_offset = eob_offset;
4229 }
4230 } else {
4231 /*
4232 * Find the number of bytes between the starting offset
4233 * and the CR or LF.
4234 */
4235 linelen = eol_offset - offset;
4236
4237 /*
4238 * Is it a CR?
4239 */
4240 if (found_needle == '\r') {
4241 /*
4242 * Yes - is it followed by an LF?
4243 */
4244 if (eol_offset + 1 >= eob_offset) {
4245 /*
4246 * Dunno - the next byte isn't in this
4247 * tvbuff.
4248 */
4249 if (desegment) {
4250 /*
4251 * We'll return -1, although that
4252 * runs the risk that if the line
4253 * really *is* terminated with a CR,
4254 * we won't properly dissect this
4255 * tvbuff.
4256 *
4257 * It's probably more likely that
4258 * the line ends with CR-LF than
4259 * that it ends with CR by itself.
4260 */
4261 return -1;
4262 }
4263 } else {
4264 /*
4265 * Well, we can at least look at the next
4266 * byte.
4267 */
4268 if (tvb_get_uint8(tvb, eol_offset + 1) == '\n') {
4269 /*
4270 * It's an LF; skip over the CR.
4271 */
4272 eol_offset++;
4273 }
4274 }
4275 }
4276
4277 /*
4278 * Return the offset of the character after the last
4279 * character in the line, skipping over the last character
4280 * in the line terminator.
4281 */
4282 if (next_offset)
4283 *next_offset = eol_offset + 1;
4284 }
4285 return linelen;
4286}
4287
4288static ws_mempbrk_pattern pbrk_crlf_dquote;
4289/*
4290 * Given a tvbuff, an offset into the tvbuff, and a length that starts
4291 * at that offset (which may be -1 for "all the way to the end of the
4292 * tvbuff"), find the end of the (putative) line that starts at the
4293 * specified offset in the tvbuff, going no further than the specified
4294 * length.
4295 *
4296 * However, treat quoted strings inside the buffer specially - don't
4297 * treat newlines in quoted strings as line terminators.
4298 *
4299 * Return the length of the line (not counting the line terminator at
4300 * the end), or the amount of data remaining in the buffer if we don't
4301 * find a line terminator.
4302 *
4303 * If "next_offset" is not NULL, set "*next_offset" to the offset of the
4304 * character past the line terminator, or past the end of the buffer if
4305 * we don't find a line terminator.
4306 */
4307int
4308tvb_find_line_end_unquoted(tvbuff_t *tvb, const int offset, int len, int *next_offset)
4309{
4310 int cur_offset, char_offset;
4311 bool_Bool is_quoted;
4312 unsigned char c = 0;
4313 int eob_offset;
4314 int linelen;
4315 static bool_Bool compiled = false0;
4316
4317 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4317, "tvb && tvb->initialized"
))))
;
4318
4319 if (len == -1)
4320 len = _tvb_captured_length_remaining(tvb, offset);
4321
4322 if (!compiled) {
4323 ws_mempbrk_compile(&pbrk_crlf_dquote, "\r\n\"");
4324 compiled = true1;
4325 }
4326
4327 /*
4328 * XXX - what if "len" is still -1, meaning "offset is past the
4329 * end of the tvbuff"?
4330 */
4331 eob_offset = offset + len;
4332
4333 cur_offset = offset;
4334 is_quoted = false0;
4335 for (;;) {
4336 /*
4337 * Is this part of the string quoted?
4338 */
4339 if (is_quoted) {
4340 /*
4341 * Yes - look only for the terminating quote.
4342 */
4343 char_offset = tvb_find_uint8(tvb, cur_offset, len,
4344 '"');
4345 } else {
4346 /*
4347 * Look either for a CR, an LF, or a '"'.
4348 */
4349 char_offset = tvb_ws_mempbrk_pattern_uint8(tvb, cur_offset, len, &pbrk_crlf_dquote, &c);
4350 }
4351 if (char_offset == -1) {
4352 /*
4353 * Not found - line is presumably continued in
4354 * next packet.
4355 * We pretend the line runs to the end of the tvbuff.
4356 */
4357 linelen = eob_offset - offset;
4358 if (next_offset)
4359 *next_offset = eob_offset;
4360 break;
4361 }
4362
4363 if (is_quoted) {
4364 /*
4365 * We're processing a quoted string.
4366 * We only looked for ", so we know it's a ";
4367 * as we're processing a quoted string, it's a
4368 * closing quote.
4369 */
4370 is_quoted = false0;
4371 } else {
4372 /*
4373 * OK, what is it?
4374 */
4375 if (c == '"') {
4376 /*
4377 * Un-quoted "; it begins a quoted
4378 * string.
4379 */
4380 is_quoted = true1;
4381 } else {
4382 /*
4383 * It's a CR or LF; we've found a line
4384 * terminator.
4385 *
4386 * Find the number of bytes between the
4387 * starting offset and the CR or LF.
4388 */
4389 linelen = char_offset - offset;
4390
4391 /*
4392 * Is it a CR?
4393 */
4394 if (c == '\r') {
4395 /*
4396 * Yes; is it followed by an LF?
4397 */
4398 if (char_offset + 1 < eob_offset &&
4399 tvb_get_uint8(tvb, char_offset + 1)
4400 == '\n') {
4401 /*
4402 * Yes; skip over the CR.
4403 */
4404 char_offset++;
4405 }
4406 }
4407
4408 /*
4409 * Return the offset of the character after
4410 * the last character in the line, skipping
4411 * over the last character in the line
4412 * terminator, and quit.
4413 */
4414 if (next_offset)
4415 *next_offset = char_offset + 1;
4416 break;
4417 }
4418 }
4419
4420 /*
4421 * Step past the character we found.
4422 */
4423 cur_offset = char_offset + 1;
4424 if (cur_offset >= eob_offset) {
4425 /*
4426 * The character we found was the last character
4427 * in the tvbuff - line is presumably continued in
4428 * next packet.
4429 * We pretend the line runs to the end of the tvbuff.
4430 */
4431 linelen = eob_offset - offset;
4432 if (next_offset)
4433 *next_offset = eob_offset;
4434 break;
4435 }
4436 }
4437 return linelen;
4438}
4439
4440/*
4441 * Copied from the mgcp dissector. (This function should be moved to /epan )
4442 * tvb_skip_wsp - Returns the position in tvb of the first non-whitespace
4443 * character following offset or offset + maxlength -1 whichever
4444 * is smaller.
4445 *
4446 * Parameters:
4447 * tvb - The tvbuff in which we are skipping whitespace.
4448 * offset - The offset in tvb from which we begin trying to skip whitespace.
4449 * maxlength - The maximum distance from offset that we may try to skip
4450 * whitespace.
4451 *
4452 * Returns: The position in tvb of the first non-whitespace
4453 * character following offset or offset + maxlength -1 whichever
4454 * is smaller.
4455 */
4456int
4457tvb_skip_wsp(tvbuff_t *tvb, const int offset, const int maxlength)
4458{
4459 int counter;
4460 int end, tvb_len;
4461 uint8_t tempchar;
4462
4463 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4463, "tvb && tvb->initialized"
))))
;
4464
4465 /* Get the length remaining */
4466 /*tvb_len = tvb_captured_length(tvb);*/
4467 tvb_len = tvb->length;
4468
4469 end = offset + maxlength;
4470 if (end >= tvb_len)
4471 {
4472 end = tvb_len;
4473 }
4474
4475 /* Skip past spaces, tabs, CRs and LFs until run out or meet something else */
4476 for (counter = offset;
4477 counter < end &&
4478 ((tempchar = tvb_get_uint8(tvb,counter)) == ' ' ||
4479 tempchar == '\t' || tempchar == '\r' || tempchar == '\n');
4480 counter++);
4481
4482 return (counter);
4483}
4484
4485int
4486tvb_skip_wsp_return(tvbuff_t *tvb, const int offset)
4487{
4488 int counter;
4489 uint8_t tempchar;
4490
4491 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4491, "tvb && tvb->initialized"
))))
;
4492
4493 for (counter = offset; counter > 0 &&
4494 ((tempchar = tvb_get_uint8(tvb,counter)) == ' ' ||
4495 tempchar == '\t' || tempchar == '\n' || tempchar == '\r'); counter--);
4496 counter++;
4497
4498 return (counter);
4499}
4500
4501int
4502tvb_skip_uint8(tvbuff_t *tvb, int offset, const int maxlength, const uint8_t ch)
4503{
4504 int end, tvb_len;
4505
4506 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4506, "tvb && tvb->initialized"
))))
;
4507
4508 /* Get the length remaining */
4509 /*tvb_len = tvb_captured_length(tvb);*/
4510 tvb_len = tvb->length;
4511
4512 end = offset + maxlength;
4513 if (end >= tvb_len)
4514 end = tvb_len;
4515
4516 while (offset < end) {
4517 uint8_t tempch = tvb_get_uint8(tvb, offset);
4518
4519 if (tempch != ch)
4520 break;
4521 offset++;
4522 }
4523
4524 return offset;
4525}
4526
4527static ws_mempbrk_pattern pbrk_whitespace;
4528
4529int tvb_get_token_len(tvbuff_t *tvb, const int offset, int len, int *next_offset, const bool_Bool desegment)
4530{
4531 int eob_offset;
4532 int eot_offset;
4533 int tokenlen;
4534 unsigned char found_needle = 0;
4535 static bool_Bool compiled = false0;
4536
4537 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4537, "tvb && tvb->initialized"
))))
;
4538
4539 if (len == -1) {
4540 len = _tvb_captured_length_remaining(tvb, offset);
4541 /* if offset is past the end of the tvbuff, len is now 0 */
4542 }
4543
4544 eob_offset = offset + len;
4545
4546 if (!compiled) {
4547 ws_mempbrk_compile(&pbrk_whitespace, " \r\n");
4548 compiled = true1;
4549 }
4550
4551 /*
4552 * Look either for a space, CR, or LF.
4553 */
4554 eot_offset = tvb_ws_mempbrk_pattern_uint8(tvb, offset, len, &pbrk_whitespace, &found_needle);
4555 if (eot_offset == -1) {
4556 /*
4557 * No space, CR or LF - token is presumably continued in next packet.
4558 */
4559 if (desegment) {
4560 /*
4561 * Tell our caller we saw no whitespace, so they can
4562 * try to desegment and get the entire line
4563 * into one tvbuff.
4564 */
4565 return -1;
4566 }
4567 else {
4568 /*
4569 * Pretend the token runs to the end of the tvbuff.
4570 */
4571 tokenlen = eob_offset - offset;
4572 if (next_offset)
4573 *next_offset = eob_offset;
4574 }
4575 }
4576 else {
4577 /*
4578 * Find the number of bytes between the starting offset
4579 * and the space, CR or LF.
4580 */
4581 tokenlen = eot_offset - offset;
4582
4583 /*
4584 * Return the offset of the character after the last
4585 * character in the line, skipping over the last character
4586 * in the line terminator.
4587 */
4588 if (next_offset)
4589 *next_offset = eot_offset + 1;
4590 }
4591 return tokenlen;
4592}
4593
4594/*
4595 * Format a bunch of data from a tvbuff as bytes, returning a pointer
4596 * to the string with the formatted data, with "punct" as a byte
4597 * separator.
4598 */
4599char *
4600tvb_bytes_to_str_punct(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, const int len, const char punct)
4601{
4602 DISSECTOR_ASSERT(len >= 0)((void) ((len >= 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4602, "len >= 0"
))))
;
4603 return bytes_to_str_punct(scope, ensure_contiguous(tvb, offset, len), len, punct)bytes_to_str_punct_maxlen(scope, ensure_contiguous(tvb, offset
, len), len, punct, 24)
;
4604}
4605
4606/*
4607 * Given a wmem scope, a tvbuff, an offset, a length, an input digit
4608 * set, and a boolean indicator, fetch BCD-encoded digits from a
4609 * tvbuff starting from either the low or high half byte of the
4610 * first byte depending on the boolean indicator (true means "start
4611 * with the high half byte, ignoring the low half byte", and false
4612 * means "start with the low half byte and proceed to the high half
4613 * byte), formating the digits into characters according to the
4614 * input digit set, and return a pointer to a UTF-8 string, allocated
4615 * using the wmem scope. A nibble of 0xf is considered a 'filler'
4616 * and will end the conversion. Similarly if odd is set the last
4617 * high nibble will be omitted. (Note that if both skip_first and
4618 * odd are true, then both the first and last semi-octet are skipped,
4619 * i.e. an even number of nibbles are considered.)
4620 */
4621char *
4622tvb_get_bcd_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int len, const dgt_set_t *dgt, bool_Bool skip_first, bool_Bool odd, bool_Bool bigendian)
4623{
4624 const uint8_t *ptr;
4625 int i = 0;
4626 char *digit_str;
4627 uint8_t octet, nibble;
4628
4629 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4629, "tvb && tvb->initialized"
))))
;
4630
4631 if (len == -1) {
4632 /*
4633 * Run to the end of the captured data.
4634 *
4635 * XXX - captured, or total?
4636 */
4637 /*length = tvb_captured_length(tvb);*/
4638 len = tvb->length;
4639 if (len < offset) {
4640 return (char *)"";
4641 }
4642 len -= offset;
4643 }
4644
4645 ptr = ensure_contiguous(tvb, offset, len);
4646
4647 /*
4648 * XXX - map illegal digits (digits that map to 0) to REPLACEMENT
4649 * CHARACTER, and have all the tables in epan/tvbuff.c use 0 rather
4650 * than '?'?
4651 */
4652 digit_str = (char *)wmem_alloc(scope, len*2 + 1);
4653
4654 while (len > 0) {
4655 octet = *ptr;
4656 if (!skip_first) {
4657 if (bigendian) {
4658 nibble = (octet >> 4) & 0x0f;
4659 } else {
4660 nibble = octet & 0x0f;
4661 }
4662 if (nibble == 0x0f) {
4663 /*
4664 * Stop digit.
4665 */
4666 break;
4667 }
4668 digit_str[i] = dgt->out[nibble];
4669 i++;
4670 }
4671 skip_first = false0;
4672
4673 /*
4674 * unpack second value in byte
4675 */
4676 if (bigendian) {
4677 nibble = octet & 0x0f;
4678 } else {
4679 nibble = octet >> 4;
4680 }
4681
4682 if (nibble == 0x0f) {
4683 /*
4684 * This is the stop digit or a filler digit. Ignore
4685 * it.
4686 */
4687 break;
4688 }
4689 if ((len == 1) && (odd == true1 )){
4690 /* Last octet, skip last high nibble in case of odd number of digits */
4691 break;
4692 }
4693 digit_str[i] = dgt->out[nibble];
4694 i++;
4695
4696 ptr++;
4697 len--;
4698 }
4699 digit_str[i] = '\0';
4700 return digit_str;
4701}
4702
4703/* XXXX Fix me - needs odd indicator added */
4704const char *
4705tvb_bcd_dig_to_str(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, const int len, const dgt_set_t *dgt, bool_Bool skip_first)
4706{
4707 if (!dgt)
4708 dgt = &Dgt0_9_bcd;
4709
4710 return tvb_get_bcd_string(scope, tvb, offset, len, dgt, skip_first, false0, false0);
4711}
4712
4713const char *
4714tvb_bcd_dig_to_str_be(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, const int len, const dgt_set_t *dgt, bool_Bool skip_first)
4715{
4716 if (!dgt)
4717 dgt = &Dgt0_9_bcd;
4718
4719 return tvb_get_bcd_string(scope, tvb, offset, len, dgt, skip_first, false0, true1);
4720}
4721
4722/*
4723 * Format a bunch of data from a tvbuff as bytes, returning a pointer
4724 * to the string with the formatted data.
4725 */
4726char *tvb_bytes_to_str(wmem_allocator_t *allocator, tvbuff_t *tvb,
4727 const int offset, const int len)
4728{
4729 DISSECTOR_ASSERT(len >= 0)((void) ((len >= 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4729, "len >= 0"
))))
;
4730 return bytes_to_str(allocator, ensure_contiguous(tvb, offset, len), len)bytes_to_str_maxlen(allocator, ensure_contiguous(tvb, offset,
len), len, 36)
;
4731}
4732
4733/* Find a needle tvbuff within a haystack tvbuff. */
4734int
4735tvb_find_tvb(tvbuff_t *haystack_tvb, tvbuff_t *needle_tvb, const int haystack_offset)
4736{
4737 unsigned haystack_abs_offset = 0, haystack_abs_length = 0;
4738 const uint8_t *haystack_data;
4739 const uint8_t *needle_data;
4740 const unsigned needle_len = needle_tvb->length;
4741 const uint8_t *location;
4742
4743 DISSECTOR_ASSERT(haystack_tvb && haystack_tvb->initialized)((void) ((haystack_tvb && haystack_tvb->initialized
) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/tvbuff.c", 4743, "haystack_tvb && haystack_tvb->initialized"
))))
;
4744
4745 if (haystack_tvb->length < 1 || needle_tvb->length < 1) {
4746 return -1;
4747 }
4748
4749 /* Get pointers to the tvbuffs' data. */
4750 haystack_data = ensure_contiguous(haystack_tvb, 0, -1);
4751 needle_data = ensure_contiguous(needle_tvb, 0, -1);
4752
4753 check_offset_length(haystack_tvb, haystack_offset, -1,
4754 &haystack_abs_offset, &haystack_abs_length);
4755
4756 location = ws_memmem(haystack_data + haystack_abs_offset, haystack_abs_length,
4757 needle_data, needle_len);
4758
4759 if (location) {
4760 return (int) (location - haystack_data);
4761 }
4762
4763 return -1;
4764}
4765
4766int
4767tvb_raw_offset(tvbuff_t *tvb)
4768{
4769 return ((tvb->raw_offset==-1) ? (tvb->raw_offset = tvb_offset_from_real_beginning(tvb)) : tvb->raw_offset);
4770}
4771
4772void
4773tvb_set_fragment(tvbuff_t *tvb)
4774{
4775 tvb->flags |= TVBUFF_FRAGMENT0x00000001;
4776}
4777
4778struct tvbuff *
4779tvb_get_ds_tvb(tvbuff_t *tvb)
4780{
4781 return(tvb->ds_tvb);
4782}
4783
4784unsigned
4785tvb_get_varint(tvbuff_t *tvb, unsigned offset, unsigned maxlen, uint64_t *value, const unsigned encoding)
4786{
4787 *value = 0;
4788
4789 switch (encoding & ENC_VARINT_MASK(0x00000002|0x00000004|0x00000008|0x00000010)) {
4790 case ENC_VARINT_PROTOBUF0x00000002:
4791 {
4792 unsigned i;
4793 uint64_t b; /* current byte */
4794
4795 for (i = 0; ((i < FT_VARINT_MAX_LEN10) && (i < maxlen)); ++i) {
4796 b = tvb_get_uint8(tvb, offset++);
4797 *value |= ((b & 0x7F) << (i * 7)); /* add lower 7 bits to val */
4798
4799 if (b < 0x80) {
4800 /* end successfully because of last byte's msb(most significant bit) is zero */
4801 return i + 1;
4802 }
4803 }
4804 break;
4805 }
4806
4807 case ENC_VARINT_ZIGZAG0x00000008:
4808 {
4809 unsigned i;
4810 uint64_t b; /* current byte */
4811
4812 for (i = 0; ((i < FT_VARINT_MAX_LEN10) && (i < maxlen)); ++i) {
4813 b = tvb_get_uint8(tvb, offset++);
4814 *value |= ((b & 0x7F) << (i * 7)); /* add lower 7 bits to val */
4815
4816 if (b < 0x80) {
4817 /* end successfully because of last byte's msb(most significant bit) is zero */
4818 *value = (*value >> 1) ^ ((*value & 1) ? -1 : 0);
4819 return i + 1;
4820 }
4821 }
4822 break;
4823 }
4824
4825 case ENC_VARINT_SDNV0x00000010:
4826 {
4827 /* Decodes similar to protobuf but in MSByte order */
4828 unsigned i;
4829 uint64_t b; /* current byte */
4830
4831 for (i = 0; ((i < FT_VARINT_MAX_LEN10) && (i < maxlen)); ++i) {
4832 b = tvb_get_uint8(tvb, offset++);
4833 if ((i == 9) && (*value >= UINT64_C(1)1UL<<(64-7))) {
4834 // guaranteed overflow, not valid SDNV
4835 return 0;
4836 }
4837 *value <<= 7;
4838 *value |= (b & 0x7F); /* add lower 7 bits to val */
4839
4840 if (b < 0x80) {
4841 /* end successfully because of last byte's msb(most significant bit) is zero */
4842 return i + 1;
4843 }
4844 }
4845 break;
4846 }
4847
4848 case ENC_VARINT_QUIC0x00000004:
4849 {
4850 /* calculate variable length */
4851 *value = tvb_get_uint8(tvb, offset);
4852 switch((*value) >> 6) {
4853 case 0: /* 0b00 => 1 byte length (6 bits Usable) */
4854 (*value) &= 0x3F;
4855 return 1;
4856 case 1: /* 0b01 => 2 bytes length (14 bits Usable) */
4857 *value = tvb_get_ntohs(tvb, offset) & 0x3FFF;
4858 return 2;
4859 case 2: /* 0b10 => 4 bytes length (30 bits Usable) */
4860 *value = tvb_get_ntohl(tvb, offset) & 0x3FFFFFFF;
4861 return 4;
4862 case 3: /* 0b11 => 8 bytes length (62 bits Usable) */
4863 *value = tvb_get_ntoh64(tvb, offset) & UINT64_C(0x3FFFFFFFFFFFFFFF)0x3FFFFFFFFFFFFFFFUL;
4864 return 8;
4865 default: /* No Possible */
4866 ws_assert_not_reached()ws_log_fatal_full("", LOG_LEVEL_ERROR, "epan/tvbuff.c", 4866,
__func__, "assertion \"not reached\" failed")
;
4867 break;
4868 }
4869 break;
4870 }
4871
4872 default:
4873 DISSECTOR_ASSERT_NOT_REACHED()(proto_report_dissector_bug("%s:%u: failed assertion \"DISSECTOR_ASSERT_NOT_REACHED\""
, "epan/tvbuff.c", 4873))
;
4874 }
4875
4876 return 0; /* 10 bytes scanned, but no bytes' msb is zero */
4877}
4878
4879/*
4880 * Editor modelines - https://www.wireshark.org/tools/modelines.html
4881 *
4882 * Local variables:
4883 * c-basic-offset: 8
4884 * tab-width: 8
4885 * indent-tabs-mode: t
4886 * End:
4887 *
4888 * vi: set shiftwidth=8 tabstop=8 noexpandtab:
4889 * :indentSize=8:tabSize=8:noTabs=false:
4890 */