Bug Summary

File:builds/wireshark/wireshark/epan/tvbuff.c
Warning:line 2397, column 58
The result of left shift is undefined because the right operand is not smaller than 64, the capacity of 'uint64_t'

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-18/lib/clang/18 -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/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-18/lib/clang/18/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 -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 -dwarf-debug-flags /usr/lib/llvm-18/bin/clang -### --analyze -x c -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 -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/libxml2 -isystem /usr/include/lua5.4 -fvisibility=hidden -fexcess-precision=fast -fstrict-flex-arrays=3 -fstack-clash-protection -fcf-protection=full -D _GLIBCXX_ASSERTIONS -fstack-protector-strong -fno-delete-null-pointer-checks -fno-strict-overflow -fno-strict-aliasing -fexceptions -Wno-format-truncation -Wno-format-nonliteral -fdiagnostics-color=always -Wno-pointer-sign -fmacro-prefix-map=/builds/wireshark/wireshark/= -fmacro-prefix-map=/builds/wireshark/wireshark/build/= -fmacro-prefix-map=../= -std=gnu11 -fPIC /builds/wireshark/wireshark/epan/tvbuff.c -o /builds/wireshark/wireshark/sbout/2024-11-17-100340-3912-1 -Xclang -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /builds/wireshark/wireshark/sbout/2024-11-17-100340-3912-1 -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"
))))
;
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) {
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) {
455 dst_len++;
456 }
457 }
458
459 /* already aligned -> shortcut */
460 if ((right == 0) && (remaining_bits == 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"
))))
;
465
466 if (_tvb_captured_length_remaining(tvb, byte_offset) > dst_len) {
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);
478
479 for (i = 0; i < (dst_len - 1); i++)
480 buf[i] = (data[i] >> right) | (data[i+1] << left);
481
482 /* Special handling for last octet */
483 buf[i] = (data[i] >> right);
484 /* Shift most significant bits from trailing octet if available */
485 if (src_len > dst_len)
486 buf[i] |= (data[i+1] << left);
487 /* Preserve only remaining bits in last octet if not multiple of 8 */
488 if (remaining_bits)
489 buf[i] &= ((1 << remaining_bits) - 1);
490
491 sub_tvb = tvb_new_child_real_data(tvb, buf, dst_len, dst_len);
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 pntoh16(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 pntoh16(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 pntoh24(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 pntoh32(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 pntoh32(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 pntoh40(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 pntoh48(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 pntoh56(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 pntoh64(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 pntoh64(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 pletoh16(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 pletoh16(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 pletoh24(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 pletoh32(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 pletoh32(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 pletoh40(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 pletoh48(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 pletoh56(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 pletoh64(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 pletoh64(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 = pntoh32(ptr + 0);
2170 guid->data2 = pntoh16(ptr + 4);
2171 guid->data3 = pntoh16(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 = pletoh32(ptr + 0);
2181 guid->data2 = pletoh16(ptr + 4);
2182 guid->data3 = pletoh16(ptr + 6);
2183 memcpy(guid->data4, ptr + 8, sizeof guid->data4);
2184}
2185
2186/*
2187 * NOTE: to support code written when proto_tree_add_item() took a
2188 * bool as its last argument, with false meaning "big-endian"
2189 * and true meaning "little-endian", we treat any non-zero value of
2190 * "encoding" as meaning "little-endian".
2191 */
2192void
2193tvb_get_guid(tvbuff_t *tvb, const int offset, e_guid_t *guid, const unsigned encoding)
2194{
2195 if (encoding) {
2196 tvb_get_letohguid(tvb, offset, guid);
2197 } else {
2198 tvb_get_ntohguid(tvb, offset, guid);
2199 }
2200}
2201
2202static const uint8_t bit_mask8[] = {
2203 0x00,
2204 0x01,
2205 0x03,
2206 0x07,
2207 0x0f,
2208 0x1f,
2209 0x3f,
2210 0x7f,
2211 0xff
2212};
2213
2214
2215/* Get a variable amount of bits
2216 *
2217 * Return a byte array with bit limited data.
2218 * When encoding is ENC_BIG_ENDIAN, the data is aligned to the left.
2219 * When encoding is ENC_LITTLE_ENDIAN, the data is aligned to the right.
2220 */
2221uint8_t *
2222tvb_get_bits_array(wmem_allocator_t *scope, tvbuff_t *tvb, const int bit_offset,
2223 size_t no_of_bits, size_t *data_length, const unsigned encoding)
2224{
2225 tvbuff_t *sub_tvb;
2226 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
2227 sub_tvb = tvb_new_octet_right_aligned(tvb, bit_offset, (int32_t) no_of_bits);
2228 } else {
2229 sub_tvb = tvb_new_octet_aligned(tvb, bit_offset, (int32_t) no_of_bits);
2230 }
2231 *data_length = tvb_reported_length(sub_tvb);
2232 return (uint8_t*)tvb_memdup(scope, sub_tvb, 0, *data_length);
2233}
2234
2235/* Get 1 - 8 bits */
2236uint8_t
2237tvb_get_bits8(tvbuff_t *tvb, unsigned bit_offset, const int no_of_bits)
2238{
2239 return (uint8_t)_tvb_get_bits64(tvb, bit_offset, no_of_bits);
2240}
2241
2242/* Get 1 - 16 bits */
2243uint16_t
2244tvb_get_bits16(tvbuff_t *tvb, unsigned bit_offset, const int no_of_bits, const unsigned encoding)
2245{
2246 return (uint16_t)tvb_get_bits64(tvb, bit_offset, no_of_bits, encoding);
2247}
2248
2249/* Get 1 - 32 bits */
2250uint32_t
2251tvb_get_bits32(tvbuff_t *tvb, unsigned bit_offset, const int no_of_bits, const unsigned encoding)
2252{
2253 return (uint32_t)tvb_get_bits64(tvb, bit_offset, no_of_bits, encoding);
2254}
2255
2256/* Get 1 - 64 bits */
2257uint64_t
2258tvb_get_bits64(tvbuff_t *tvb, unsigned bit_offset, const int no_of_bits, const unsigned encoding)
2259{
2260 /* encoding determines bit numbering within octet array */
2261 if (encoding & ENC_LITTLE_ENDIAN0x80000000) {
2
Assuming the condition is true
3
Taking true branch
2262 return _tvb_get_bits64_le(tvb, bit_offset, no_of_bits);
4
Calling '_tvb_get_bits64_le'
2263 } else {
2264 return _tvb_get_bits64(tvb, bit_offset, no_of_bits);
2265 }
2266}
2267
2268/*
2269 * This function will dissect a sequence of bits that does not need to be byte aligned; the bits
2270 * set will be shown in the tree as ..10 10.. and the integer value returned if return_value is set.
2271 * Offset should be given in bits from the start of the tvb.
2272 * Bits within octet are numbered from MSB (0) to LSB (7). Bit at bit_offset is return value most significant bit.
2273 * The function tolerates requests for more than 64 bits, but will only return the least significant 64 bits.
2274 */
2275static uint64_t
2276_tvb_get_bits64(tvbuff_t *tvb, unsigned bit_offset, const int total_no_of_bits)
2277{
2278 uint64_t value;
2279 unsigned octet_offset = bit_offset >> 3;
2280 uint8_t required_bits_in_first_octet = 8 - (bit_offset % 8);
2281
2282 if(required_bits_in_first_octet > total_no_of_bits)
2283 {
2284 /* the required bits don't extend to the end of the first octet */
2285 uint8_t right_shift = required_bits_in_first_octet - total_no_of_bits;
2286 value = (tvb_get_uint8(tvb, octet_offset) >> right_shift) & bit_mask8[total_no_of_bits % 8];
2287 }
2288 else
2289 {
2290 uint8_t remaining_bit_length = total_no_of_bits;
2291
2292 /* get the bits up to the first octet boundary */
2293 value = 0;
2294 required_bits_in_first_octet %= 8;
2295 if(required_bits_in_first_octet != 0)
2296 {
2297 value = tvb_get_uint8(tvb, octet_offset) & bit_mask8[required_bits_in_first_octet];
2298 remaining_bit_length -= required_bits_in_first_octet;
2299 octet_offset ++;
2300 }
2301 /* take the biggest words, shorts or octets that we can */
2302 while (remaining_bit_length > 7)
2303 {
2304 switch (remaining_bit_length >> 4)
2305 {
2306 case 0:
2307 /* 8 - 15 bits. (note that 0 - 7 would have dropped out of the while() loop) */
2308 value <<= 8;
2309 value += tvb_get_uint8(tvb, octet_offset);
2310 remaining_bit_length -= 8;
2311 octet_offset ++;
2312 break;
2313
2314 case 1:
2315 /* 16 - 31 bits */
2316 value <<= 16;
2317 value += tvb_get_ntohs(tvb, octet_offset);
2318 remaining_bit_length -= 16;
2319 octet_offset += 2;
2320 break;
2321
2322 case 2:
2323 case 3:
2324 /* 32 - 63 bits */
2325 value <<= 32;
2326 value += tvb_get_ntohl(tvb, octet_offset);
2327 remaining_bit_length -= 32;
2328 octet_offset += 4;
2329 break;
2330
2331 default:
2332 /* 64 bits (or more???) */
2333 value = tvb_get_ntoh64(tvb, octet_offset);
2334 remaining_bit_length -= 64;
2335 octet_offset += 8;
2336 break;
2337 }
2338 }
2339 /* get bits from any partial octet at the tail */
2340 if(remaining_bit_length)
2341 {
2342 value <<= remaining_bit_length;
2343 value += (tvb_get_uint8(tvb, octet_offset) >> (8 - remaining_bit_length));
2344 }
2345 }
2346 return value;
2347}
2348
2349/*
2350 * Offset should be given in bits from the start of the tvb.
2351 * Bits within octet are numbered from LSB (0) to MSB (7). Bit at bit_offset is return value least significant bit.
2352 * The function tolerates requests for more than 64 bits, but will only return the least significant 64 bits.
2353 */
2354static uint64_t
2355_tvb_get_bits64_le(tvbuff_t *tvb, unsigned bit_offset, const int total_no_of_bits)
2356{
2357 uint64_t value = 0;
2358 unsigned octet_offset = bit_offset / 8;
2359 int remaining_bits = total_no_of_bits;
2360 int shift = 0;
2361
2362 if (remaining_bits > 64)
5
Assuming 'remaining_bits' is <= 64
6
Taking false branch
2363 {
2364 remaining_bits = 64;
2365 }
2366
2367 if (bit_offset % 8)
7
Assuming the condition is true
8
Taking true branch
2368 {
2369 /* not aligned, extract bits from first octet */
2370 shift = 8 - (bit_offset % 8);
2371 value = tvb_get_uint8(tvb, octet_offset) >> (bit_offset % 8);
2372 if (shift > remaining_bits)
9
Assuming 'shift' is <= 'remaining_bits'
10
Taking false branch
2373 {
2374 /* keep only the requested bits */
2375 value &= (UINT64_C(1)1UL << remaining_bits) - 1;
2376 remaining_bits = 0;
2377 }
2378 else
2379 {
2380 remaining_bits -= shift;
2381 }
2382 octet_offset++;
2383 }
2384
2385 while (remaining_bits > 0)
11
Assuming 'remaining_bits' is > 0
12
Loop condition is true. Entering loop body
16
Assuming 'remaining_bits' is > 0
17
Loop condition is true. Entering loop body
22
Assuming 'remaining_bits' is > 0
23
Loop condition is true. Entering loop body
2386 {
2387 /* take the biggest words, shorts or octets that we can */
2388 if (remaining_bits >= 32)
13
Assuming 'remaining_bits' is >= 32
14
Taking true branch
18
Assuming 'remaining_bits' is >= 32
19
Taking true branch
24
Assuming 'remaining_bits' is < 32
25
Taking false branch
2389 {
2390 value |= ((uint64_t)tvb_get_letohl(tvb, octet_offset) << shift);
15
Assuming right operand of bit shift is less than 64
20
Assuming right operand of bit shift is less than 64
2391 shift += 32;
21
Value assigned to 'shift'
2392 remaining_bits -= 32;
2393 octet_offset += 4;
2394 }
2395 else if (remaining_bits >= 16)
26
Assuming 'remaining_bits' is >= 16
27
Taking true branch
2396 {
2397 value |= ((uint64_t)tvb_get_letohs(tvb, octet_offset) << shift);
28
The result of left shift is undefined because the right operand is not smaller than 64, the capacity of 'uint64_t'
2398 shift += 16;
2399 remaining_bits -= 16;
2400 octet_offset += 2;
2401 }
2402 else if (remaining_bits >= 8)
2403 {
2404 value |= ((uint64_t)tvb_get_uint8(tvb, octet_offset) << shift);
2405 shift += 8;
2406 remaining_bits -= 8;
2407 octet_offset += 1;
2408 }
2409 else
2410 {
2411 unsigned mask = (1 << remaining_bits) - 1;
2412 value |= (((uint64_t)tvb_get_uint8(tvb, octet_offset) & mask) << shift);
2413 shift += remaining_bits;
2414 remaining_bits = 0;
2415 octet_offset += 1;
2416 }
2417 }
2418 return value;
2419}
2420
2421/* Get 1 - 32 bits (should be deprecated as same as tvb_get_bits32??) */
2422uint32_t
2423tvb_get_bits(tvbuff_t *tvb, const unsigned bit_offset, const int no_of_bits, const unsigned encoding)
2424{
2425 return (uint32_t)tvb_get_bits64(tvb, bit_offset, no_of_bits, encoding);
1
Calling 'tvb_get_bits64'
2426}
2427
2428static int
2429tvb_find_uint8_generic(tvbuff_t *tvb, unsigned abs_offset, unsigned limit, uint8_t needle)
2430{
2431 const uint8_t *ptr;
2432 const uint8_t *result;
2433
2434 ptr = ensure_contiguous(tvb, abs_offset, limit); /* tvb_get_ptr() */
2435 if (!ptr)
2436 return -1;
2437
2438 result = (const uint8_t *) memchr(ptr, needle, limit);
2439 if (!result)
2440 return -1;
2441
2442 return (int) ((result - ptr) + abs_offset);
2443}
2444
2445/* Find first occurrence of needle in tvbuff, starting at offset. Searches
2446 * at most maxlength number of bytes; if maxlength is -1, searches to
2447 * end of tvbuff.
2448 * Returns the offset of the found needle, or -1 if not found.
2449 * Will not throw an exception, even if maxlength exceeds boundary of tvbuff;
2450 * in that case, -1 will be returned if the boundary is reached before
2451 * finding needle. */
2452int
2453tvb_find_uint8(tvbuff_t *tvb, const int offset, const int maxlength, const uint8_t needle)
2454{
2455 const uint8_t *result;
2456 unsigned abs_offset = 0;
2457 unsigned limit = 0;
2458 int exception;
2459
2460 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2460, "tvb && tvb->initialized"
))))
;
2461
2462 exception = compute_offset_and_remaining(tvb, offset, &abs_offset, &limit);
2463 if (exception)
2464 THROW(exception)except_throw(1, (exception), ((void*)0));
2465
2466 /* Only search to end of tvbuff, w/o throwing exception. */
2467 if (maxlength >= 0 && limit > (unsigned) maxlength) {
2468 /* Maximum length doesn't go past end of tvbuff; search
2469 to that value. */
2470 limit = (unsigned) maxlength;
2471 }
2472
2473 /* If we have real data, perform our search now. */
2474 if (tvb->real_data) {
2475 result = (const uint8_t *)memchr(tvb->real_data + abs_offset, needle, limit);
2476 if (result == NULL((void*)0)) {
2477 return -1;
2478 }
2479 else {
2480 return (int) (result - tvb->real_data);
2481 }
2482 }
2483
2484 if (tvb->ops->tvb_find_uint8)
2485 return tvb->ops->tvb_find_uint8(tvb, abs_offset, limit, needle);
2486
2487 return tvb_find_uint8_generic(tvb, offset, limit, needle);
2488}
2489
2490/* Same as tvb_find_uint8() with 16bit needle. */
2491int
2492tvb_find_uint16(tvbuff_t *tvb, const int offset, const int maxlength,
2493 const uint16_t needle)
2494{
2495 unsigned abs_offset = 0;
2496 unsigned limit = 0;
2497 int exception;
2498
2499 exception = compute_offset_and_remaining(tvb, offset, &abs_offset, &limit);
2500 if (exception)
2501 THROW(exception)except_throw(1, (exception), ((void*)0));
2502
2503 /* Only search to end of tvbuff, w/o throwing exception. */
2504 if (maxlength >= 0 && limit > (unsigned) maxlength) {
2505 /* Maximum length doesn't go past end of tvbuff; search
2506 to that value. */
2507 limit = (unsigned) maxlength;
2508 }
2509
2510 const uint8_t needle1 = ((needle & 0xFF00) >> 8);
2511 const uint8_t needle2 = ((needle & 0x00FF) >> 0);
2512 unsigned searched_bytes = 0;
2513 unsigned pos = abs_offset;
2514
2515 do {
2516 int offset1 =
2517 tvb_find_uint8(tvb, pos, limit - searched_bytes, needle1);
2518 int offset2 = -1;
2519
2520 if (offset1 == -1) {
2521 return -1;
2522 }
2523
2524 searched_bytes = (unsigned)offset1 - abs_offset + 1;
2525
2526 if (searched_bytes >= limit) {
2527 return -1;
2528 }
2529
2530 offset2 = tvb_find_uint8(tvb, offset1 + 1, 1, needle2);
2531
2532 searched_bytes += 1;
2533
2534 if (offset2 != -1) {
2535 if (searched_bytes > limit) {
2536 return -1;
2537 }
2538 return offset1;
2539 }
2540
2541 pos = offset1 + 1;
2542 } while (searched_bytes < limit);
2543
2544 return -1;
2545}
2546
2547static inline int
2548tvb_ws_mempbrk_uint8_generic(tvbuff_t *tvb, unsigned abs_offset, unsigned limit, const ws_mempbrk_pattern* pattern, unsigned char *found_needle)
2549{
2550 const uint8_t *ptr;
2551 const uint8_t *result;
2552
2553 ptr = ensure_contiguous(tvb, abs_offset, limit); /* tvb_get_ptr */
2554 if (!ptr)
2555 return -1;
2556
2557 result = ws_mempbrk_exec(ptr, limit, pattern, found_needle);
2558 if (!result)
2559 return -1;
2560
2561 return (int) ((result - ptr) + abs_offset);
2562}
2563
2564
2565/* Find first occurrence of any of the pattern chars in tvbuff, starting at offset.
2566 * Searches at most maxlength number of bytes; if maxlength is -1, searches
2567 * to end of tvbuff.
2568 * Returns the offset of the found needle, or -1 if not found.
2569 * Will not throw an exception, even if maxlength exceeds boundary of tvbuff;
2570 * in that case, -1 will be returned if the boundary is reached before
2571 * finding needle. */
2572int
2573tvb_ws_mempbrk_pattern_uint8(tvbuff_t *tvb, const int offset, const int maxlength,
2574 const ws_mempbrk_pattern* pattern, unsigned char *found_needle)
2575{
2576 const uint8_t *result;
2577 unsigned abs_offset = 0;
2578 unsigned limit = 0;
2579 int exception;
2580
2581 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2581, "tvb && tvb->initialized"
))))
;
2582
2583 exception = compute_offset_and_remaining(tvb, offset, &abs_offset, &limit);
2584 if (exception)
2585 THROW(exception)except_throw(1, (exception), ((void*)0));
2586
2587 /* Only search to end of tvbuff, w/o throwing exception. */
2588 if (limit > (unsigned) maxlength) {
2589 /* Maximum length doesn't go past end of tvbuff; search
2590 to that value. */
2591 limit = maxlength;
2592 }
2593
2594 /* If we have real data, perform our search now. */
2595 if (tvb->real_data) {
2596 result = ws_mempbrk_exec(tvb->real_data + abs_offset, limit, pattern, found_needle);
2597 if (result == NULL((void*)0)) {
2598 return -1;
2599 }
2600 else {
2601 return (int) (result - tvb->real_data);
2602 }
2603 }
2604
2605 if (tvb->ops->tvb_ws_mempbrk_pattern_uint8)
2606 return tvb->ops->tvb_ws_mempbrk_pattern_uint8(tvb, abs_offset, limit, pattern, found_needle);
2607
2608 return tvb_ws_mempbrk_uint8_generic(tvb, abs_offset, limit, pattern, found_needle);
2609}
2610
2611/* Find size of stringz (NUL-terminated string) by looking for terminating
2612 * NUL. The size of the string includes the terminating NUL.
2613 *
2614 * If the NUL isn't found, it throws the appropriate exception.
2615 */
2616unsigned
2617tvb_strsize(tvbuff_t *tvb, const int offset)
2618{
2619 unsigned abs_offset = 0, junk_length;
2620 int nul_offset;
2621
2622 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2622, "tvb && tvb->initialized"
))))
;
2623
2624 check_offset_length(tvb, offset, 0, &abs_offset, &junk_length);
2625 nul_offset = tvb_find_uint8(tvb, abs_offset, -1, 0);
2626 if (nul_offset == -1) {
2627 /*
2628 * OK, we hit the end of the tvbuff, so we should throw
2629 * an exception.
2630 */
2631 if (tvb->length < tvb->contained_length) {
2632 THROW(BoundsError)except_throw(1, (1), ((void*)0));
2633 } else if (tvb->flags & TVBUFF_FRAGMENT0x00000001) {
2634 THROW(FragmentBoundsError)except_throw(1, (4), ((void*)0));
2635 } else if (tvb->length < tvb->reported_length) {
2636 THROW(ContainedBoundsError)except_throw(1, (2), ((void*)0));
2637 } else {
2638 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
2639 }
2640 }
2641 return (nul_offset - abs_offset) + 1;
2642}
2643
2644/* UTF-16/UCS-2 version of tvb_strsize */
2645/* Returns number of bytes including the (two-bytes) null terminator */
2646unsigned
2647tvb_unicode_strsize(tvbuff_t *tvb, const int offset)
2648{
2649 unsigned i = 0;
2650 gunichar2 uchar;
2651
2652 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2652, "tvb && tvb->initialized"
))))
;
2653
2654 do {
2655 /* Endianness doesn't matter when looking for null */
2656 uchar = tvb_get_ntohs(tvb, offset + i);
2657 i += 2;
2658 } while(uchar != 0);
2659
2660 return i;
2661}
2662
2663/* Find length of string by looking for end of string ('\0'), up to
2664 * 'maxlength' characters'; if 'maxlength' is -1, searches to end
2665 * of tvbuff.
2666 * Returns -1 if 'maxlength' reached before finding EOS. */
2667int
2668tvb_strnlen(tvbuff_t *tvb, const int offset, const unsigned maxlength)
2669{
2670 int result_offset;
2671 unsigned abs_offset = 0, junk_length;
2672
2673 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2673, "tvb && tvb->initialized"
))))
;
2674
2675 check_offset_length(tvb, offset, 0, &abs_offset, &junk_length);
2676
2677 result_offset = tvb_find_uint8(tvb, abs_offset, maxlength, 0);
2678
2679 if (result_offset == -1) {
2680 return -1;
2681 }
2682 else {
2683 return result_offset - abs_offset;
2684 }
2685}
2686
2687/*
2688 * Implement strneql etc
2689 */
2690
2691/*
2692 * Call strncmp after checking if enough chars left, returning 0 if
2693 * it returns 0 (meaning "equal") and -1 otherwise, otherwise return -1.
2694 */
2695int
2696tvb_strneql(tvbuff_t *tvb, const int offset, const char *str, const size_t size)
2697{
2698 const uint8_t *ptr;
2699
2700 ptr = ensure_contiguous_no_exception(tvb, offset, (int)size, NULL((void*)0));
2701
2702 if (ptr) {
2703 int cmp = strncmp((const char *)ptr, str, size);
2704
2705 /*
2706 * Return 0 if equal, -1 otherwise.
2707 */
2708 return (cmp == 0 ? 0 : -1);
2709 } else {
2710 /*
2711 * Not enough characters in the tvbuff to match the
2712 * string.
2713 */
2714 return -1;
2715 }
2716}
2717
2718/*
2719 * Call g_ascii_strncasecmp after checking if enough chars left, returning
2720 * 0 if it returns 0 (meaning "equal") and -1 otherwise, otherwise return -1.
2721 */
2722int
2723tvb_strncaseeql(tvbuff_t *tvb, const int offset, const char *str, const size_t size)
2724{
2725 const uint8_t *ptr;
2726
2727 ptr = ensure_contiguous_no_exception(tvb, offset, (int)size, NULL((void*)0));
2728
2729 if (ptr) {
2730 int cmp = g_ascii_strncasecmp((const char *)ptr, str, size);
2731
2732 /*
2733 * Return 0 if equal, -1 otherwise.
2734 */
2735 return (cmp == 0 ? 0 : -1);
2736 } else {
2737 /*
2738 * Not enough characters in the tvbuff to match the
2739 * string.
2740 */
2741 return -1;
2742 }
2743}
2744
2745/*
2746 * Check that the tvbuff contains at least size bytes, starting at
2747 * offset, and that those bytes are equal to str. Return 0 for success
2748 * and -1 for error. This function does not throw an exception.
2749 */
2750int
2751tvb_memeql(tvbuff_t *tvb, const int offset, const uint8_t *str, size_t size)
2752{
2753 const uint8_t *ptr;
2754
2755 ptr = ensure_contiguous_no_exception(tvb, offset, (int) size, NULL((void*)0));
2756
2757 if (ptr) {
2758 int cmp = memcmp(ptr, str, size);
2759
2760 /*
2761 * Return 0 if equal, -1 otherwise.
2762 */
2763 return (cmp == 0 ? 0 : -1);
2764 } else {
2765 /*
2766 * Not enough characters in the tvbuff to match the
2767 * string.
2768 */
2769 return -1;
2770 }
2771}
2772
2773/**
2774 * Format the data in the tvb from offset for size.
2775 */
2776char *
2777tvb_format_text(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, const int size)
2778{
2779 const uint8_t *ptr;
2780 int len;
2781
2782 len = (size > 0) ? size : 0;
2783
2784 ptr = ensure_contiguous(tvb, offset, size);
2785 return format_text(scope, ptr, len);
2786}
2787
2788/*
2789 * Format the data in the tvb from offset for length ...
2790 */
2791char *
2792tvb_format_text_wsp(wmem_allocator_t* allocator, tvbuff_t *tvb, const int offset, const int size)
2793{
2794 const uint8_t *ptr;
2795 int len;
2796
2797 len = (size > 0) ? size : 0;
2798
2799 ptr = ensure_contiguous(tvb, offset, size);
2800 return format_text_wsp(allocator, ptr, len);
2801}
2802
2803/**
2804 * Like "tvb_format_text()", but for null-padded strings; don't show
2805 * the null padding characters as "\000".
2806 */
2807char *
2808tvb_format_stringzpad(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, const int size)
2809{
2810 const uint8_t *ptr, *p;
2811 int len;
2812 int stringlen;
2813
2814 len = (size > 0) ? size : 0;
2815
2816 ptr = ensure_contiguous(tvb, offset, size);
2817 for (p = ptr, stringlen = 0; stringlen < len && *p != '\0'; p++, stringlen++)
2818 ;
2819 return format_text(scope, ptr, stringlen);
2820}
2821
2822/*
2823 * Like "tvb_format_text_wsp()", but for null-padded strings; don't show
2824 * the null padding characters as "\000".
2825 */
2826char *
2827tvb_format_stringzpad_wsp(wmem_allocator_t* allocator, tvbuff_t *tvb, const int offset, const int size)
2828{
2829 const uint8_t *ptr, *p;
2830 int len;
2831 int stringlen;
2832
2833 len = (size > 0) ? size : 0;
2834
2835 ptr = ensure_contiguous(tvb, offset, size);
2836 for (p = ptr, stringlen = 0; stringlen < len && *p != '\0'; p++, stringlen++)
2837 ;
2838 return format_text_wsp(allocator, ptr, stringlen);
2839}
2840
2841/*
2842 * All string functions below take a scope as an argument.
2843 *
2844 *
2845 * If scope is NULL, memory is allocated with g_malloc() and user must
2846 * explicitly free it with g_free().
2847 * If scope is not NULL, memory is allocated with the corresponding pool
2848 * lifetime.
2849 *
2850 * All functions throw an exception if the tvbuff ends before the string
2851 * does.
2852 */
2853
2854/*
2855 * Given a wmem scope, a tvbuff, an offset, and a length, treat the string
2856 * of bytes referred to by the tvbuff, offset, and length as an ASCII string,
2857 * with all bytes with the high-order bit set being invalid, and return a
2858 * pointer to a UTF-8 string, allocated using the wmem scope.
2859 *
2860 * Octets with the highest bit set will be converted to the Unicode
2861 * REPLACEMENT CHARACTER.
2862 */
2863static uint8_t *
2864tvb_get_ascii_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length)
2865{
2866 const uint8_t *ptr;
2867
2868 ptr = ensure_contiguous(tvb, offset, length);
2869 return get_ascii_string(scope, ptr, length);
2870}
2871
2872/*
2873 * Given a wmem scope, a tvbuff, an offset, a length, and a translation table,
2874 * treat the string of bytes referred to by the tvbuff, offset, and length
2875 * as a string encoded using one octet per character, with octets with the
2876 * high-order bit clear being mapped by the translation table to 2-byte
2877 * Unicode Basic Multilingual Plane characters (including REPLACEMENT
2878 * CHARACTER) and octets with the high-order bit set being mapped to
2879 * REPLACEMENT CHARACTER, and return a pointer to a UTF-8 string,
2880 * allocated using the wmem scope.
2881 *
2882 * Octets with the highest bit set will be converted to the Unicode
2883 * REPLACEMENT CHARACTER.
2884 */
2885static uint8_t *
2886tvb_get_iso_646_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length, const gunichar2 table[0x80])
2887{
2888 const uint8_t *ptr;
2889
2890 ptr = ensure_contiguous(tvb, offset, length);
2891 return get_iso_646_string(scope, ptr, length, table);
2892}
2893
2894/*
2895 * Given a wmem scope, a tvbuff, an offset, and a length, treat the string
2896 * of bytes referred to by the tvbuff, the offset. and the length as a UTF-8
2897 * string, and return a pointer to a UTF-8 string, allocated using the wmem
2898 * scope, with all ill-formed sequences replaced with the Unicode REPLACEMENT
2899 * CHARACTER according to the recommended "best practices" given in the Unicode
2900 * Standard and specified by W3C/WHATWG.
2901 *
2902 * Note that in conformance with the Unicode Standard, this treats three
2903 * byte sequences corresponding to UTF-16 surrogate halves (paired or unpaired)
2904 * and two byte overlong encodings of 7-bit ASCII characters as invalid and
2905 * substitutes REPLACEMENT CHARACTER for them. Explicit support for nonstandard
2906 * derivative encoding formats (e.g. CESU-8, Java Modified UTF-8, WTF-8) could
2907 * be added later.
2908 */
2909static uint8_t *
2910tvb_get_utf_8_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, const int length)
2911{
2912 const uint8_t *ptr;
2913
2914 ptr = ensure_contiguous(tvb, offset, length);
2915 return get_utf_8_string(scope, ptr, length);
2916}
2917
2918/*
2919 * Given a wmem scope, a tvbuff, an offset, and a length, treat the string
2920 * of bytes referred to by the tvbuff, the offset, and the length as a
2921 * raw string, and return a pointer to that string, allocated using the
2922 * wmem scope. This means a null is appended at the end, but no replacement
2923 * checking is done otherwise, unlike tvb_get_utf_8_string().
2924 *
2925 * Also, this one allows a length of -1 to mean get all, but does not
2926 * allow a negative offset.
2927 */
2928static inline uint8_t *
2929tvb_get_raw_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, const int length)
2930{
2931 uint8_t *strbuf;
2932 int abs_length = length;
2933
2934 DISSECTOR_ASSERT(offset >= 0)((void) ((offset >= 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2934, "offset >= 0"
))))
;
2935 DISSECTOR_ASSERT(abs_length >= -1)((void) ((abs_length >= -1) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 2935, "abs_length >= -1"
))))
;
2936
2937 if (abs_length < 0)
2938 abs_length = tvb->length - offset;
2939
2940 tvb_ensure_bytes_exist(tvb, offset, abs_length);
2941 strbuf = (uint8_t *)wmem_alloc(scope, abs_length + 1);
2942 tvb_memcpy(tvb, strbuf, offset, abs_length);
2943 strbuf[abs_length] = '\0';
2944 return strbuf;
2945}
2946
2947/*
2948 * Given a wmem scope, a tvbuff, an offset, and a length, treat the string
2949 * of bytes referred to by the tvbuff, the offset, and the length as an
2950 * ISO 8859/1 string, and return a pointer to a UTF-8 string, allocated
2951 * using the wmem scope.
2952 */
2953static uint8_t *
2954tvb_get_string_8859_1(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length)
2955{
2956 const uint8_t *ptr;
2957
2958 ptr = ensure_contiguous(tvb, offset, length);
2959 return get_8859_1_string(scope, ptr, length);
2960}
2961
2962/*
2963 * Given a wmem scope, a tvbuff, an offset, a length, and a translation
2964 * table, treat the string of bytes referred to by the tvbuff, the offset,
2965 * and the length as a string encoded using one octet per character, with
2966 * octets with the high-order bit clear being ASCII and octets with the
2967 * high-order bit set being mapped by the translation table to 2-byte
2968 * Unicode Basic Multilingual Plane characters (including REPLACEMENT
2969 * CHARACTER), and return a pointer to a UTF-8 string, allocated with the
2970 * wmem scope.
2971 */
2972static uint8_t *
2973tvb_get_string_unichar2(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length, const gunichar2 table[0x80])
2974{
2975 const uint8_t *ptr;
2976
2977 ptr = ensure_contiguous(tvb, offset, length);
2978 return get_unichar2_string(scope, ptr, length, table);
2979}
2980
2981/*
2982 * Given a wmem scope, a tvbuff, an offset, a length, and an encoding
2983 * giving the byte order, treat the string of bytes referred to by the
2984 * tvbuff, the offset, and the length as a UCS-2 encoded string in
2985 * the byte order in question, containing characters from the Basic
2986 * Multilingual Plane (plane 0) of Unicode, and return a pointer to a
2987 * UTF-8 string, allocated with the wmem scope.
2988 *
2989 * Encoding parameter should be ENC_BIG_ENDIAN or ENC_LITTLE_ENDIAN.
2990 *
2991 * Specify length in bytes.
2992 *
2993 * XXX - should map lead and trail surrogate values to REPLACEMENT
2994 * CHARACTERs (0xFFFD)?
2995 * XXX - if there are an odd number of bytes, should put a
2996 * REPLACEMENT CHARACTER at the end.
2997 */
2998static uint8_t *
2999tvb_get_ucs_2_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int length, const unsigned encoding)
3000{
3001 const uint8_t *ptr;
3002
3003 ptr = ensure_contiguous(tvb, offset, length);
3004 return get_ucs_2_string(scope, ptr, length, encoding);
3005}
3006
3007/*
3008 * Given a wmem scope, a tvbuff, an offset, a length, and an encoding
3009 * giving the byte order, treat the string of bytes referred to by the
3010 * tvbuff, the offset, and the length as a UTF-16 encoded string in
3011 * the byte order in question, and return a pointer to a UTF-8 string,
3012 * allocated with the wmem scope.
3013 *
3014 * Encoding parameter should be ENC_BIG_ENDIAN or ENC_LITTLE_ENDIAN.
3015 *
3016 * Specify length in bytes.
3017 *
3018 * XXX - should map surrogate errors to REPLACEMENT CHARACTERs (0xFFFD).
3019 * XXX - should map code points > 10FFFF to REPLACEMENT CHARACTERs.
3020 * XXX - if there are an odd number of bytes, should put a
3021 * REPLACEMENT CHARACTER at the end.
3022 */
3023static uint8_t *
3024tvb_get_utf_16_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int length, const unsigned encoding)
3025{
3026 const uint8_t *ptr;
3027
3028 ptr = ensure_contiguous(tvb, offset, length);
3029 return get_utf_16_string(scope, ptr, length, encoding);
3030}
3031
3032/*
3033 * Given a wmem scope, a tvbuff, an offset, a length, and an encoding
3034 * giving the byte order, treat the string of bytes referred to by the
3035 * tvbuff, the offset, and the length as a UCS-4 encoded string in
3036 * the byte order in question, and return a pointer to a UTF-8 string,
3037 * allocated with the wmem scope.
3038 *
3039 * Encoding parameter should be ENC_BIG_ENDIAN or ENC_LITTLE_ENDIAN
3040 *
3041 * Specify length in bytes
3042 *
3043 * XXX - should map lead and trail surrogate values to a "substitute"
3044 * UTF-8 character?
3045 * XXX - should map code points > 10FFFF to REPLACEMENT CHARACTERs.
3046 * XXX - if the number of bytes isn't a multiple of 4, should put a
3047 * REPLACEMENT CHARACTER at the end.
3048 */
3049static char *
3050tvb_get_ucs_4_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int length, const unsigned encoding)
3051{
3052 const uint8_t *ptr;
3053
3054 ptr = ensure_contiguous(tvb, offset, length);
3055 return get_ucs_4_string(scope, ptr, length, encoding);
3056}
3057
3058char *
3059tvb_get_ts_23_038_7bits_string_packed(wmem_allocator_t *scope, tvbuff_t *tvb,
3060 const int bit_offset, int no_of_chars)
3061{
3062 int in_offset = bit_offset >> 3; /* Current pointer to the input buffer */
3063 int length = ((no_of_chars + 1) * 7 + (bit_offset & 0x07)) >> 3;
3064 const uint8_t *ptr;
3065
3066 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 3066, "tvb && tvb->initialized"
))))
;
3067
3068 ptr = ensure_contiguous(tvb, in_offset, length);
3069 return get_ts_23_038_7bits_string_packed(scope, ptr, bit_offset, no_of_chars);
3070}
3071
3072char *
3073tvb_get_ts_23_038_7bits_string_unpacked(wmem_allocator_t *scope, tvbuff_t *tvb,
3074 const int offset, int length)
3075{
3076 const uint8_t *ptr;
3077
3078 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 3078, "tvb && tvb->initialized"
))))
;
3079
3080 ptr = ensure_contiguous(tvb, offset, length);
3081 return get_ts_23_038_7bits_string_unpacked(scope, ptr, length);
3082}
3083
3084char *
3085tvb_get_etsi_ts_102_221_annex_a_string(wmem_allocator_t *scope, tvbuff_t *tvb,
3086 const int offset, int length)
3087{
3088 const uint8_t *ptr;
3089
3090 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 3090, "tvb && tvb->initialized"
))))
;
3091
3092 ptr = ensure_contiguous(tvb, offset, length);
3093 return get_etsi_ts_102_221_annex_a_string(scope, ptr, length);
3094}
3095
3096char *
3097tvb_get_ascii_7bits_string(wmem_allocator_t *scope, tvbuff_t *tvb,
3098 const int bit_offset, int no_of_chars)
3099{
3100 int in_offset = bit_offset >> 3; /* Current pointer to the input buffer */
3101 int length = ((no_of_chars + 1) * 7 + (bit_offset & 0x07)) >> 3;
3102 const uint8_t *ptr;
3103
3104 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 3104, "tvb && tvb->initialized"
))))
;
3105
3106 ptr = ensure_contiguous(tvb, in_offset, length);
3107 return get_ascii_7bits_string(scope, ptr, bit_offset, no_of_chars);
3108}
3109
3110/*
3111 * Given a wmem scope, a tvbuff, an offset, a length, and a translation
3112 * table, treat the string of bytes referred to by the tvbuff, the offset,
3113 * and the length as a string encoded using one octet per character, with
3114 * octets being mapped by the translation table to 2-byte Unicode Basic
3115 * Multilingual Plane characters (including REPLACEMENT CHARACTER), and
3116 * return a pointer to a UTF-8 string, allocated with the wmem scope.
3117 */
3118static uint8_t *
3119tvb_get_nonascii_unichar2_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length, const gunichar2 table[256])
3120{
3121 const uint8_t *ptr;
3122
3123 ptr = ensure_contiguous(tvb, offset, length);
3124 return get_nonascii_unichar2_string(scope, ptr, length, table);
3125}
3126
3127/*
3128 * Given a wmem scope, a tvbuff, an offset, and a length, treat the bytes
3129 * referred to by the tvbuff, offset, and length as a GB18030 encoded string,
3130 * and return a pointer to a UTF-8 string, allocated with the wmem scope,
3131 * converted having substituted REPLACEMENT CHARACTER according to the
3132 * Unicode Standard 5.22 U+FFFD Substitution for Conversion.
3133 * ( https://www.unicode.org/versions/Unicode13.0.0/ch05.pdf )
3134 *
3135 * As expected, this will also decode GBK and GB2312 strings.
3136 */
3137static uint8_t *
3138tvb_get_gb18030_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length)
3139{
3140 const uint8_t *ptr;
3141
3142 ptr = ensure_contiguous(tvb, offset, length);
3143 return get_gb18030_string(scope, ptr, length);
3144}
3145
3146/*
3147 * Given a wmem scope, a tvbuff, an offset, and a length, treat the bytes
3148 * referred to by the tvbuff, offset, and length as a EUC-KR encoded string,
3149 * and return a pointer to a UTF-8 string, allocated with the wmem scope,
3150 * converted having substituted REPLACEMENT CHARACTER according to the
3151 * Unicode Standard 5.22 U+FFFD Substitution for Conversion.
3152 * ( https://www.unicode.org/versions/Unicode13.0.0/ch05.pdf )
3153 */
3154static uint8_t *
3155tvb_get_euc_kr_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length)
3156{
3157 const uint8_t *ptr;
3158
3159 ptr = ensure_contiguous(tvb, offset, length);
3160 return get_euc_kr_string(scope, ptr, length);
3161}
3162
3163static uint8_t *
3164tvb_get_t61_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length)
3165{
3166 const uint8_t *ptr;
3167
3168 ptr = ensure_contiguous(tvb, offset, length);
3169 return get_t61_string(scope, ptr, length);
3170}
3171
3172/*
3173 * Encoding tables for BCD strings.
3174 */
3175static const dgt_set_t Dgt0_9_bcd = {
3176 {
3177 /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
3178 '0','1','2','3','4','5','6','7','8','9','?','?','?','?','?','?'
3179 }
3180};
3181
3182static const dgt_set_t Dgt_keypad_abc_tbcd = {
3183 {
3184 /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
3185 '0','1','2','3','4','5','6','7','8','9','*','#','a','b','c','?'
3186 }
3187};
3188
3189static const dgt_set_t Dgt_ansi_tbcd = {
3190 {
3191 /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
3192 '0','1','2','3','4','5','6','7','8','9','?','B','C','*','#','?'
3193 }
3194};
3195
3196static const dgt_set_t Dgt_dect_standard_4bits_tbcd = {
3197 {
3198 /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
3199 '0','1','2','3','4','5','6','7','8','9','?',' ','?','?','?','?'
3200 }
3201};
3202
3203static uint8_t *
3204tvb_get_apn_string(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset,
3205 int length)
3206{
3207 wmem_strbuf_t *str;
3208
3209 /*
3210 * This is a domain name.
3211 *
3212 * 3GPP TS 23.003, section 19.4.2 "Fully Qualified Domain Names
3213 * (FQDNs)", subsection 19.4.2.1 "General", says:
3214 *
3215 * The encoding of any identifier used as part of a Fully
3216 * Qualifed Domain Name (FQDN) shall follow the Name Syntax
3217 * defined in IETF RFC 2181 [18], IETF RFC 1035 [19] and
3218 * IETF RFC 1123 [20]. An FQDN consists of one or more
3219 * labels. Each label is coded as a one octet length field
3220 * followed by that number of octets coded as 8 bit ASCII
3221 * characters.
3222 *
3223 * so this does not appear to use full-blown DNS compression -
3224 * the upper 2 bits of the length don't indicate that it's a
3225 * pointer or an extended label (RFC 2673).
3226 */
3227 str = wmem_strbuf_new_sized(scope, length + 1);
3228 if (length > 0) {
3229 const uint8_t *ptr;
3230
3231 ptr = ensure_contiguous(tvb, offset, length);
3232
3233 for (;;) {
3234 unsigned label_len;
3235
3236 /*
3237 * Process this label.
3238 */
3239 label_len = *ptr;
3240 ptr++;
3241 length--;
3242
3243 while (label_len != 0) {
3244 uint8_t ch;
3245
3246 if (length == 0)
3247 goto end;
3248
3249 ch = *ptr;
3250 if (ch < 0x80)
3251 wmem_strbuf_append_c(str, ch);
3252 else
3253 wmem_strbuf_append_unichar_repl(str)wmem_strbuf_append_unichar(str, 0x00FFFD);
3254 ptr++;
3255 label_len--;
3256 length--;
3257 }
3258
3259 if (length == 0)
3260 goto end;
3261
3262 wmem_strbuf_append_c(str, '.');
3263 }
3264 }
3265
3266end:
3267 return (uint8_t *) wmem_strbuf_finalize(str);
3268}
3269
3270static uint8_t *
3271tvb_get_dect_standard_8bits_string(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int length)
3272{
3273 const uint8_t *ptr;
3274
3275 ptr = ensure_contiguous(tvb, offset, length);
3276 return get_dect_standard_8bits_string(scope, ptr, length);
3277}
3278
3279/*
3280 * Given a tvbuff, an offset, a length, and an encoding, allocate a
3281 * buffer big enough to hold a non-null-terminated string of that length
3282 * at that offset, plus a trailing '\0', copy into the buffer the
3283 * string as converted from the appropriate encoding to UTF-8, and
3284 * return a pointer to the string.
3285 */
3286uint8_t *
3287tvb_get_string_enc(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset,
3288 const int length, const unsigned encoding)
3289{
3290 uint8_t *strptr;
3291 bool_Bool odd, skip_first;
3292
3293 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 3293, "tvb && tvb->initialized"
))))
;
3294
3295 /* make sure length = -1 fails */
3296 if (length < 0) {
3297 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
3298 }
3299
3300 switch (encoding & ENC_CHARENCODING_MASK0x0000FFFE) {
3301
3302 case ENC_ASCII0x00000000:
3303 default:
3304 /*
3305 * For now, we treat bogus values as meaning
3306 * "ASCII" rather than reporting an error,
3307 * for the benefit of old dissectors written
3308 * when the last argument to proto_tree_add_item()
3309 * was a bool for the byte order, not an
3310 * encoding value, and passed non-zero values
3311 * other than true to mean "little-endian".
3312 */
3313 strptr = tvb_get_ascii_string(scope, tvb, offset, length);
3314 break;
3315
3316 case ENC_UTF_80x00000002:
3317 strptr = tvb_get_utf_8_string(scope, tvb, offset, length);
3318 break;
3319
3320 case ENC_UTF_160x00000004:
3321 strptr = tvb_get_utf_16_string(scope, tvb, offset, length,
3322 encoding & (ENC_LITTLE_ENDIAN0x80000000|ENC_BOM0x20000000));
3323 break;
3324
3325 case ENC_UCS_20x00000006:
3326 strptr = tvb_get_ucs_2_string(scope, tvb, offset, length,
3327 encoding & (ENC_LITTLE_ENDIAN0x80000000|ENC_BOM0x20000000));
3328 break;
3329
3330 case ENC_UCS_40x00000008:
3331 strptr = tvb_get_ucs_4_string(scope, tvb, offset, length,
3332 encoding & (ENC_LITTLE_ENDIAN0x80000000|ENC_BOM0x20000000));
3333 break;
3334
3335 case ENC_ISO_8859_10x0000000A:
3336 /*
3337 * ISO 8859-1 printable code point values are equal
3338 * to the equivalent Unicode code point value, so
3339 * no translation table is needed.
3340 */
3341 strptr = tvb_get_string_8859_1(scope, tvb, offset, length);
3342 break;
3343
3344 case ENC_ISO_8859_20x0000000C:
3345 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_2);
3346 break;
3347
3348 case ENC_ISO_8859_30x0000000E:
3349 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_3);
3350 break;
3351
3352 case ENC_ISO_8859_40x00000010:
3353 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_4);
3354 break;
3355
3356 case ENC_ISO_8859_50x00000012:
3357 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_5);
3358 break;
3359
3360 case ENC_ISO_8859_60x00000014:
3361 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_6);
3362 break;
3363
3364 case ENC_ISO_8859_70x00000016:
3365 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_7);
3366 break;
3367
3368 case ENC_ISO_8859_80x00000018:
3369 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_8);
3370 break;
3371
3372 case ENC_ISO_8859_90x0000001A:
3373 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_9);
3374 break;
3375
3376 case ENC_ISO_8859_100x0000001C:
3377 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_10);
3378 break;
3379
3380 case ENC_ISO_8859_110x0000001E:
3381 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_11);
3382 break;
3383
3384 case ENC_ISO_8859_130x00000022:
3385 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_13);
3386 break;
3387
3388 case ENC_ISO_8859_140x00000024:
3389 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_14);
3390 break;
3391
3392 case ENC_ISO_8859_150x00000026:
3393 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_15);
3394 break;
3395
3396 case ENC_ISO_8859_160x00000028:
3397 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_iso_8859_16);
3398 break;
3399
3400 case ENC_WINDOWS_12500x0000002A:
3401 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_cp1250);
3402 break;
3403
3404 case ENC_WINDOWS_12510x0000003C:
3405 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_cp1251);
3406 break;
3407
3408 case ENC_WINDOWS_12520x0000003A:
3409 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_cp1252);
3410 break;
3411
3412 case ENC_MAC_ROMAN0x00000030:
3413 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_mac_roman);
3414 break;
3415
3416 case ENC_CP4370x00000032:
3417 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_cp437);
3418 break;
3419
3420 case ENC_CP8550x0000003E:
3421 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_cp855);
3422 break;
3423
3424 case ENC_CP8660x00000040:
3425 strptr = tvb_get_string_unichar2(scope, tvb, offset, length, charset_table_cp866);
3426 break;
3427
3428 case ENC_ISO_646_BASIC0x00000042:
3429 strptr = tvb_get_iso_646_string(scope, tvb, offset, length, charset_table_iso_646_basic);
3430 break;
3431
3432 case ENC_3GPP_TS_23_038_7BITS_PACKED0x0000002C:
3433 {
3434 int bit_offset = offset << 3;
3435 int no_of_chars = (length << 3) / 7;
3436 strptr = tvb_get_ts_23_038_7bits_string_packed(scope, tvb, bit_offset, no_of_chars);
3437 }
3438 break;
3439
3440 case ENC_ASCII_7BITS0x00000034:
3441 {
3442 int bit_offset = offset << 3;
3443 int no_of_chars = (length << 3) / 7;
3444 strptr = tvb_get_ascii_7bits_string(scope, tvb, bit_offset, no_of_chars);
3445 }
3446 break;
3447
3448 case ENC_EBCDIC0x0000002E:
3449 /*
3450 * "Common" EBCDIC, covering all characters with the
3451 * same code point in all Roman-alphabet EBCDIC code
3452 * pages.
3453 */
3454 strptr = tvb_get_nonascii_unichar2_string(scope, tvb, offset, length, charset_table_ebcdic);
3455 break;
3456
3457 case ENC_EBCDIC_CP0370x00000038:
3458 /*
3459 * EBCDIC code page 037.
3460 */
3461 strptr = tvb_get_nonascii_unichar2_string(scope, tvb, offset, length, charset_table_ebcdic_cp037);
3462 break;
3463
3464 case ENC_EBCDIC_CP5000x00000060:
3465 /*
3466 * EBCDIC code page 500.
3467 */
3468 strptr = tvb_get_nonascii_unichar2_string(scope, tvb, offset, length, charset_table_ebcdic_cp500);
3469 break;
3470
3471 case ENC_T610x00000036:
3472 strptr = tvb_get_t61_string(scope, tvb, offset, length);
3473 break;
3474
3475 case ENC_BCD_DIGITS_0_90x00000044:
3476 /*
3477 * Packed BCD, with digits 0-9.
3478 */
3479 odd = (encoding & ENC_BCD_ODD_NUM_DIG0x00010000) >> 16;
3480 skip_first = (encoding & ENC_BCD_SKIP_FIRST0x00020000) >> 17;
3481 strptr = tvb_get_bcd_string(scope, tvb, offset, length, &Dgt0_9_bcd, skip_first, odd, !(encoding & ENC_LITTLE_ENDIAN0x80000000));
3482 break;
3483
3484 case ENC_KEYPAD_ABC_TBCD0x00000046:
3485 /*
3486 * Keypad-with-a/b/c "telephony BCD" - packed BCD, with
3487 * digits 0-9 and symbols *, #, a, b, and c.
3488 */
3489 odd = (encoding & ENC_BCD_ODD_NUM_DIG0x00010000) >> 16;
3490 skip_first = (encoding & ENC_BCD_SKIP_FIRST0x00020000) >> 17;
3491 strptr = tvb_get_bcd_string(scope, tvb, offset, length, &Dgt_keypad_abc_tbcd, skip_first, odd, !(encoding & ENC_LITTLE_ENDIAN0x80000000));
3492 break;
3493
3494 case ENC_KEYPAD_BC_TBCD0x00000048:
3495 /*
3496 * Keypad-with-B/C "telephony BCD" - packed BCD, with
3497 * digits 0-9 and symbols B, C, *, and #.
3498 */
3499 odd = (encoding & ENC_BCD_ODD_NUM_DIG0x00010000) >> 16;
3500 skip_first = (encoding & ENC_BCD_SKIP_FIRST0x00020000) >> 17;
3501 strptr = tvb_get_bcd_string(scope, tvb, offset, length, &Dgt_ansi_tbcd, skip_first, odd, !(encoding & ENC_LITTLE_ENDIAN0x80000000));
3502 break;
3503
3504 case ENC_3GPP_TS_23_038_7BITS_UNPACKED0x0000004C:
3505 strptr = tvb_get_ts_23_038_7bits_string_unpacked(scope, tvb, offset, length);
3506 break;
3507
3508 case ENC_ETSI_TS_102_221_ANNEX_A0x0000004E:
3509 strptr = tvb_get_etsi_ts_102_221_annex_a_string(scope, tvb, offset, length);
3510 break;
3511
3512 case ENC_GB180300x00000050:
3513 strptr = tvb_get_gb18030_string(scope, tvb, offset, length);
3514 break;
3515
3516 case ENC_EUC_KR0x00000052:
3517 strptr = tvb_get_euc_kr_string(scope, tvb, offset, length);
3518 break;
3519
3520 case ENC_APN_STR0x00000054:
3521 strptr = tvb_get_apn_string(scope, tvb, offset, length);
3522 break;
3523
3524 case ENC_DECT_STANDARD_8BITS0x00000056:
3525 strptr = tvb_get_dect_standard_8bits_string(scope, tvb, offset, length);
3526 break;
3527
3528 case ENC_DECT_STANDARD_4BITS_TBCD0x00000058:
3529 /*
3530 * DECT standard 4bits "telephony BCD" - packed BCD, with
3531 * digits 0-9 and symbol SPACE for 0xb.
3532 */
3533 odd = (encoding & ENC_BCD_ODD_NUM_DIG0x00010000) >> 16;
3534 skip_first = (encoding & ENC_BCD_SKIP_FIRST0x00020000) >> 17;
3535 strptr = tvb_get_bcd_string(scope, tvb, offset, length, &Dgt_dect_standard_4bits_tbcd, skip_first, odd, false0);
3536 break;
3537 }
3538 return strptr;
3539}
3540
3541/*
3542 * This is like tvb_get_string_enc(), except that it handles null-padded
3543 * strings.
3544 *
3545 * Currently, string values are stored as UTF-8 null-terminated strings,
3546 * so nothing needs to be done differently for null-padded strings; we
3547 * could save a little memory by not storing the null padding.
3548 *
3549 * If we ever store string values differently, in a fashion that doesn't
3550 * involve null termination, that might change.
3551 */
3552uint8_t *
3553tvb_get_stringzpad(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset,
3554 const int length, const unsigned encoding)
3555{
3556 return tvb_get_string_enc(scope, tvb, offset, length, encoding);
3557}
3558
3559/*
3560 * These routines are like the above routines, except that they handle
3561 * null-terminated strings. They find the length of that string (and
3562 * throw an exception if the tvbuff ends before we find the null), and
3563 * also return through a pointer the length of the string, in bytes,
3564 * including the terminating null (the terminating null being 2 bytes
3565 * for UCS-2 and UTF-16, 4 bytes for UCS-4, and 1 byte for other
3566 * encodings).
3567 */
3568static uint8_t *
3569tvb_get_ascii_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp)
3570{
3571 unsigned size;
3572 const uint8_t *ptr;
3573
3574 size = tvb_strsize(tvb, offset);
3575 ptr = ensure_contiguous(tvb, offset, size);
3576 /* XXX, conversion between signed/unsigned integer */
3577 if (lengthp)
3578 *lengthp = size;
3579 return get_ascii_string(scope, ptr, size);
3580}
3581
3582static uint8_t *
3583tvb_get_iso_646_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp, const gunichar2 table[0x80])
3584{
3585 unsigned size;
3586 const uint8_t *ptr;
3587
3588 size = tvb_strsize(tvb, offset);
3589 ptr = ensure_contiguous(tvb, offset, size);
3590 /* XXX, conversion between signed/unsigned integer */
3591 if (lengthp)
3592 *lengthp = size;
3593 return get_iso_646_string(scope, ptr, size, table);
3594}
3595
3596static uint8_t *
3597tvb_get_utf_8_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int *lengthp)
3598{
3599 unsigned size;
3600 const uint8_t *ptr;
3601
3602 size = tvb_strsize(tvb, offset);
3603 ptr = ensure_contiguous(tvb, offset, size);
3604 /* XXX, conversion between signed/unsigned integer */
3605 if (lengthp)
3606 *lengthp = size;
3607 return get_utf_8_string(scope, ptr, size);
3608}
3609
3610static uint8_t *
3611tvb_get_stringz_8859_1(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp)
3612{
3613 unsigned size;
3614 const uint8_t *ptr;
3615
3616 size = tvb_strsize(tvb, offset);
3617 ptr = ensure_contiguous(tvb, offset, size);
3618 /* XXX, conversion between signed/unsigned integer */
3619 if (lengthp)
3620 *lengthp = size;
3621 return get_8859_1_string(scope, ptr, size);
3622}
3623
3624static uint8_t *
3625tvb_get_stringz_unichar2(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp, const gunichar2 table[0x80])
3626{
3627 unsigned size;
3628 const uint8_t *ptr;
3629
3630 size = tvb_strsize(tvb, offset);
3631 ptr = ensure_contiguous(tvb, offset, size);
3632 /* XXX, conversion between signed/unsigned integer */
3633 if (lengthp)
3634 *lengthp = size;
3635 return get_unichar2_string(scope, ptr, size, table);
3636}
3637
3638/*
3639 * Given a tvbuff and an offset, with the offset assumed to refer to
3640 * a null-terminated string, find the length of that string (and throw
3641 * an exception if the tvbuff ends before we find the null), ensure that
3642 * the TVB is flat, and return a pointer to the string (in the TVB).
3643 * Also return the length of the string (including the terminating null)
3644 * through a pointer.
3645 *
3646 * As long as we aren't using composite TVBs, this saves the cycles used
3647 * (often unnecessariliy) in allocating a buffer and copying the string into
3648 * it. (If we do start using composite TVBs, we may want to replace this
3649 * function with the _ephemeral version.)
3650 */
3651const uint8_t *
3652tvb_get_const_stringz(tvbuff_t *tvb, const int offset, int *lengthp)
3653{
3654 unsigned size;
3655 const uint8_t *strptr;
3656
3657 size = tvb_strsize(tvb, offset);
3658 strptr = ensure_contiguous(tvb, offset, size);
3659 if (lengthp)
3660 *lengthp = size;
3661 return strptr;
3662}
3663
3664static char *
3665tvb_get_ucs_2_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int *lengthp, const unsigned encoding)
3666{
3667 int size; /* Number of bytes in string */
3668 const uint8_t *ptr;
3669
3670 size = tvb_unicode_strsize(tvb, offset);
3671 ptr = ensure_contiguous(tvb, offset, size);
3672 /* XXX, conversion between signed/unsigned integer */
3673 if (lengthp)
3674 *lengthp = size;
3675 return get_ucs_2_string(scope, ptr, size, encoding);
3676}
3677
3678static char *
3679tvb_get_utf_16_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int *lengthp, const unsigned encoding)
3680{
3681 int size;
3682 const uint8_t *ptr;
3683
3684 size = tvb_unicode_strsize(tvb, offset);
3685 ptr = ensure_contiguous(tvb, offset, size);
3686 /* XXX, conversion between signed/unsigned integer */
3687 if (lengthp)
3688 *lengthp = size;
3689 return get_utf_16_string(scope, ptr, size, encoding);
3690}
3691
3692static char *
3693tvb_get_ucs_4_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int *lengthp, const unsigned encoding)
3694{
3695 int size;
3696 gunichar uchar;
3697 const uint8_t *ptr;
3698
3699 size = 0;
3700 do {
3701 /* Endianness doesn't matter when looking for null */
3702 uchar = tvb_get_ntohl(tvb, offset + size);
3703 size += 4;
3704 } while(uchar != 0);
3705
3706 ptr = ensure_contiguous(tvb, offset, size);
3707 /* XXX, conversion between signed/unsigned integer */
3708 if (lengthp)
3709 *lengthp = size;
3710 return get_ucs_4_string(scope, ptr, size, encoding);
3711}
3712
3713static uint8_t *
3714tvb_get_nonascii_unichar2_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp, const gunichar2 table[256])
3715{
3716 unsigned size;
3717 const uint8_t *ptr;
3718
3719 size = tvb_strsize(tvb, offset);
3720 ptr = ensure_contiguous(tvb, offset, size);
3721 /* XXX, conversion between signed/unsigned integer */
3722 if (lengthp)
3723 *lengthp = size;
3724 return get_nonascii_unichar2_string(scope, ptr, size, table);
3725}
3726
3727static uint8_t *
3728tvb_get_t61_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp)
3729{
3730 unsigned size;
3731 const uint8_t *ptr;
3732
3733 size = tvb_strsize(tvb, offset);
3734 ptr = ensure_contiguous(tvb, offset, size);
3735 /* XXX, conversion between signed/unsigned integer */
3736 if (lengthp)
3737 *lengthp = size;
3738 return get_t61_string(scope, ptr, size);
3739}
3740
3741static uint8_t *
3742tvb_get_gb18030_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp)
3743{
3744 unsigned size;
3745 const uint8_t *ptr;
3746
3747 size = tvb_strsize(tvb, offset);
3748 ptr = ensure_contiguous(tvb, offset, size);
3749 /* XXX, conversion between signed/unsigned integer */
3750 if (lengthp)
3751 *lengthp = size;
3752 return get_gb18030_string(scope, ptr, size);
3753}
3754
3755static uint8_t *
3756tvb_get_euc_kr_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp)
3757{
3758 unsigned size;
3759 const uint8_t *ptr;
3760
3761 size = tvb_strsize(tvb, offset);
3762 ptr = ensure_contiguous(tvb, offset, size);
3763 /* XXX, conversion between signed/unsigned integer */
3764 if (lengthp)
3765 *lengthp = size;
3766 return get_euc_kr_string(scope, ptr, size);
3767}
3768
3769static uint8_t *
3770tvb_get_dect_standard_8bits_stringz(wmem_allocator_t *scope, tvbuff_t *tvb, int offset, int *lengthp)
3771{
3772 unsigned size;
3773 const uint8_t *ptr;
3774
3775 size = tvb_strsize(tvb, offset);
3776 ptr = ensure_contiguous(tvb, offset, size);
3777 /* XXX, conversion between signed/unsigned integer */
3778 if (lengthp)
3779 *lengthp = size;
3780 return get_t61_string(scope, ptr, size);
3781}
3782
3783uint8_t *
3784tvb_get_stringz_enc(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, int *lengthp, const unsigned encoding)
3785{
3786 uint8_t *strptr;
3787
3788 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 3788, "tvb && tvb->initialized"
))))
;
3789
3790 switch (encoding & ENC_CHARENCODING_MASK0x0000FFFE) {
3791
3792 case ENC_ASCII0x00000000:
3793 default:
3794 /*
3795 * For now, we treat bogus values as meaning
3796 * "ASCII" rather than reporting an error,
3797 * for the benefit of old dissectors written
3798 * when the last argument to proto_tree_add_item()
3799 * was a bool for the byte order, not an
3800 * encoding value, and passed non-zero values
3801 * other than true to mean "little-endian".
3802 */
3803 strptr = tvb_get_ascii_stringz(scope, tvb, offset, lengthp);
3804 break;
3805
3806 case ENC_UTF_80x00000002:
3807 /*
3808 * XXX - should map all invalid UTF-8 sequences
3809 * to a "substitute" UTF-8 character.
3810 * XXX - should map code points > 10FFFF to REPLACEMENT
3811 * CHARACTERs.
3812 */
3813 strptr = tvb_get_utf_8_stringz(scope, tvb, offset, lengthp);
3814 break;
3815
3816 case ENC_UTF_160x00000004:
3817 strptr = tvb_get_utf_16_stringz(scope, tvb, offset, lengthp,
3818 encoding & (ENC_LITTLE_ENDIAN0x80000000|ENC_BOM0x20000000));
3819 break;
3820
3821 case ENC_UCS_20x00000006:
3822 strptr = tvb_get_ucs_2_stringz(scope, tvb, offset, lengthp,
3823 encoding & (ENC_LITTLE_ENDIAN0x80000000|ENC_BOM0x20000000));
3824 break;
3825
3826 case ENC_UCS_40x00000008:
3827 strptr = tvb_get_ucs_4_stringz(scope, tvb, offset, lengthp,
3828 encoding & (ENC_LITTLE_ENDIAN0x80000000|ENC_BOM0x20000000));
3829 break;
3830
3831 case ENC_ISO_8859_10x0000000A:
3832 /*
3833 * ISO 8859-1 printable code point values are equal
3834 * to the equivalent Unicode code point value, so
3835 * no translation table is needed.
3836 */
3837 strptr = tvb_get_stringz_8859_1(scope, tvb, offset, lengthp);
3838 break;
3839
3840 case ENC_ISO_8859_20x0000000C:
3841 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_2);
3842 break;
3843
3844 case ENC_ISO_8859_30x0000000E:
3845 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_3);
3846 break;
3847
3848 case ENC_ISO_8859_40x00000010:
3849 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_4);
3850 break;
3851
3852 case ENC_ISO_8859_50x00000012:
3853 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_5);
3854 break;
3855
3856 case ENC_ISO_8859_60x00000014:
3857 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_6);
3858 break;
3859
3860 case ENC_ISO_8859_70x00000016:
3861 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_7);
3862 break;
3863
3864 case ENC_ISO_8859_80x00000018:
3865 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_8);
3866 break;
3867
3868 case ENC_ISO_8859_90x0000001A:
3869 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_9);
3870 break;
3871
3872 case ENC_ISO_8859_100x0000001C:
3873 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_10);
3874 break;
3875
3876 case ENC_ISO_8859_110x0000001E:
3877 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_11);
3878 break;
3879
3880 case ENC_ISO_8859_130x00000022:
3881 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_13);
3882 break;
3883
3884 case ENC_ISO_8859_140x00000024:
3885 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_14);
3886 break;
3887
3888 case ENC_ISO_8859_150x00000026:
3889 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_15);
3890 break;
3891
3892 case ENC_ISO_8859_160x00000028:
3893 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_iso_8859_16);
3894 break;
3895
3896 case ENC_WINDOWS_12500x0000002A:
3897 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_cp1250);
3898 break;
3899
3900 case ENC_WINDOWS_12510x0000003C:
3901 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_cp1251);
3902 break;
3903
3904 case ENC_WINDOWS_12520x0000003A:
3905 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_cp1252);
3906 break;
3907
3908 case ENC_MAC_ROMAN0x00000030:
3909 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_mac_roman);
3910 break;
3911
3912 case ENC_CP4370x00000032:
3913 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_cp437);
3914 break;
3915
3916 case ENC_CP8550x0000003E:
3917 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_cp855);
3918 break;
3919
3920 case ENC_CP8660x00000040:
3921 strptr = tvb_get_stringz_unichar2(scope, tvb, offset, lengthp, charset_table_cp866);
3922 break;
3923
3924 case ENC_ISO_646_BASIC0x00000042:
3925 strptr = tvb_get_iso_646_stringz(scope, tvb, offset, lengthp, charset_table_iso_646_basic);
3926 break;
3927
3928 case ENC_3GPP_TS_23_038_7BITS_PACKED0x0000002C:
3929 case ENC_3GPP_TS_23_038_7BITS_UNPACKED0x0000004C:
3930 case ENC_ETSI_TS_102_221_ANNEX_A0x0000004E:
3931 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"
)
;
3932 break;
3933
3934 case ENC_ASCII_7BITS0x00000034:
3935 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"
)
;
3936 break;
3937
3938 case ENC_EBCDIC0x0000002E:
3939 /*
3940 * "Common" EBCDIC, covering all characters with the
3941 * same code point in all Roman-alphabet EBCDIC code
3942 * pages.
3943 */
3944 strptr = tvb_get_nonascii_unichar2_stringz(scope, tvb, offset, lengthp, charset_table_ebcdic);
3945 break;
3946
3947 case ENC_EBCDIC_CP0370x00000038:
3948 /*
3949 * EBCDIC code page 037.
3950 */
3951 strptr = tvb_get_nonascii_unichar2_stringz(scope, tvb, offset, lengthp, charset_table_ebcdic_cp037);
3952 break;
3953
3954 case ENC_EBCDIC_CP5000x00000060:
3955 /*
3956 * EBCDIC code page 500.
3957 */
3958 strptr = tvb_get_nonascii_unichar2_stringz(scope, tvb, offset, lengthp, charset_table_ebcdic_cp500);
3959 break;
3960
3961 case ENC_T610x00000036:
3962 strptr = tvb_get_t61_stringz(scope, tvb, offset, lengthp);
3963 break;
3964
3965 case ENC_GB180300x00000050:
3966 strptr = tvb_get_gb18030_stringz(scope, tvb, offset, lengthp);
3967 break;
3968
3969 case ENC_EUC_KR0x00000052:
3970 strptr = tvb_get_euc_kr_stringz(scope, tvb, offset, lengthp);
3971 break;
3972
3973 case ENC_DECT_STANDARD_8BITS0x00000056:
3974 strptr = tvb_get_dect_standard_8bits_stringz(scope, tvb, offset, lengthp);
3975 break;
3976 }
3977
3978 return strptr;
3979}
3980
3981/* Looks for a stringz (NUL-terminated string) in tvbuff and copies
3982 * no more than bufsize number of bytes, including terminating NUL, to buffer.
3983 * Returns length of string (not including terminating NUL), or -1 if the string was
3984 * truncated in the buffer due to not having reached the terminating NUL.
3985 * In this way, it acts like snprintf().
3986 *
3987 * bufsize MUST be greater than 0.
3988 *
3989 * When processing a packet where the remaining number of bytes is less
3990 * than bufsize, an exception is not thrown if the end of the packet
3991 * is reached before the NUL is found. If no NUL is found before reaching
3992 * the end of the short packet, -1 is still returned, and the string
3993 * is truncated with a NUL, albeit not at buffer[bufsize - 1], but
3994 * at the correct spot, terminating the string.
3995 *
3996 * *bytes_copied will contain the number of bytes actually copied,
3997 * including the terminating-NUL.
3998 */
3999static int
4000_tvb_get_raw_bytes_as_stringz(tvbuff_t *tvb, const int offset, const unsigned bufsize, uint8_t* buffer, int *bytes_copied)
4001{
4002 int stringlen;
4003 unsigned abs_offset = 0;
4004 int limit, len = 0;
4005 bool_Bool decreased_max = false0;
4006
4007 /* Only read to end of tvbuff, w/o throwing exception. */
4008 check_offset_length(tvb, offset, -1, &abs_offset, &len);
4009
4010 /* There must at least be room for the terminating NUL. */
4011 DISSECTOR_ASSERT(bufsize != 0)((void) ((bufsize != 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4011, "bufsize != 0"
))))
;
4012
4013 /* If there's no room for anything else, just return the NUL. */
4014 if (bufsize == 1) {
4015 buffer[0] = 0;
4016 *bytes_copied = 1;
4017 return 0;
4018 }
4019
4020 /* check_offset_length() won't throw an exception if we're
4021 * looking at the byte immediately after the end of the tvbuff. */
4022 if (len == 0) {
4023 THROW(ReportedBoundsError)except_throw(1, (3), ((void*)0));
4024 }
4025
4026 /* This should not happen because check_offset_length() would
4027 * have already thrown an exception if 'offset' were out-of-bounds.
4028 */
4029 DISSECTOR_ASSERT(len != -1)((void) ((len != -1) ? (void)0 : (proto_report_dissector_bug(
"%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4029, "len != -1"
))))
;
4030
4031 /*
4032 * If we've been passed a negative number, bufsize will
4033 * be huge.
4034 */
4035 DISSECTOR_ASSERT(bufsize <= INT_MAX)((void) ((bufsize <= 2147483647) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4035, "bufsize <= 2147483647"
))))
;
4036
4037 if ((unsigned)len < bufsize) {
4038 limit = len;
4039 decreased_max = true1;
4040 }
4041 else {
4042 limit = bufsize;
4043 }
4044
4045 stringlen = tvb_strnlen(tvb, abs_offset, limit - 1);
4046 /* If NUL wasn't found, copy the data and return -1 */
4047 if (stringlen == -1) {
4048 tvb_memcpy(tvb, buffer, abs_offset, limit);
4049 if (decreased_max) {
4050 buffer[limit] = 0;
4051 /* Add 1 for the extra NUL that we set at buffer[limit],
4052 * pretending that it was copied as part of the string. */
4053 *bytes_copied = limit + 1;
4054 }
4055 else {
4056 *bytes_copied = limit;
4057 }
4058 return -1;
4059 }
4060
4061 /* Copy the string to buffer */
4062 tvb_memcpy(tvb, buffer, abs_offset, stringlen + 1);
4063 *bytes_copied = stringlen + 1;
4064 return stringlen;
4065}
4066
4067int
4068tvb_get_raw_bytes_as_stringz(tvbuff_t *tvb, const int offset, const unsigned bufsize, uint8_t* buffer)
4069{
4070 int len, bytes_copied;
4071
4072 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4072, "tvb && tvb->initialized"
))))
;
4073
4074 len = _tvb_get_raw_bytes_as_stringz(tvb, offset, bufsize, buffer, &bytes_copied);
4075
4076 if (len == -1) {
4077 buffer[bufsize - 1] = 0;
4078 return bytes_copied - 1;
4079 }
4080 else {
4081 return len;
4082 }
4083}
4084
4085/*
4086 * Given a tvbuff, an offset into the tvbuff, a buffer, and a buffer size,
4087 * extract as many raw bytes from the tvbuff, starting at the offset,
4088 * as 1) are available in the tvbuff and 2) will fit in the buffer, leaving
4089 * room for a terminating NUL.
4090 */
4091int
4092tvb_get_raw_bytes_as_string(tvbuff_t *tvb, const int offset, char *buffer, size_t bufsize)
4093{
4094 int len = 0;
4095
4096 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4096, "tvb && tvb->initialized"
))))
;
4097
4098 /* There must be room for the string and the terminating NUL. */
4099 DISSECTOR_ASSERT(bufsize > 0)((void) ((bufsize > 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4099, "bufsize > 0"
))))
;
4100
4101 DISSECTOR_ASSERT(bufsize - 1 < INT_MAX)((void) ((bufsize - 1 < 2147483647) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4101, "bufsize - 1 < 2147483647"
))))
;
4102
4103 len = tvb_captured_length_remaining(tvb, offset);
4104 if (len <= 0) {
4105 buffer[0] = '\0';
4106 return 0;
4107 }
4108 if (len > (int)(bufsize - 1))
4109 len = (int)(bufsize - 1);
4110
4111 /* Copy the string to buffer */
4112 tvb_memcpy(tvb, buffer, offset, len);
4113 buffer[len] = '\0';
4114 return len;
4115}
4116
4117bool_Bool
4118tvb_ascii_isprint(tvbuff_t *tvb, const int offset, const int length)
4119{
4120 const uint8_t* buf = tvb_get_ptr(tvb, offset, length);
4121 unsigned abs_offset, abs_length = length;
4122
4123 if (length == -1) {
4124 /* tvb_get_ptr has already checked for exceptions. */
4125 compute_offset_and_remaining(tvb, offset, &abs_offset, &abs_length);
4126 }
4127 for (unsigned i = 0; i < abs_length; i++, buf++)
4128 if (!g_ascii_isprint(*buf)((g_ascii_table[(guchar) (*buf)] & G_ASCII_PRINT) != 0))
4129 return false0;
4130
4131 return true1;
4132}
4133
4134bool_Bool
4135tvb_utf_8_isprint(tvbuff_t *tvb, const int offset, const int length)
4136{
4137 const uint8_t* buf = tvb_get_ptr(tvb, offset, length);
4138 unsigned abs_offset, abs_length = length;
4139
4140 if (length == -1) {
4141 /* tvb_get_ptr has already checked for exceptions. */
4142 compute_offset_and_remaining(tvb, offset, &abs_offset, &abs_length);
4143 }
4144
4145 return isprint_utf8_string(buf, abs_length);
4146}
4147
4148bool_Bool
4149tvb_ascii_isdigit(tvbuff_t *tvb, const int offset, const int length)
4150{
4151 const uint8_t* buf = tvb_get_ptr(tvb, offset, length);
4152 unsigned abs_offset, abs_length = length;
4153
4154 if (length == -1) {
4155 /* tvb_get_ptr has already checked for exceptions. */
4156 compute_offset_and_remaining(tvb, offset, &abs_offset, &abs_length);
4157 }
4158 for (unsigned i = 0; i < abs_length; i++, buf++)
4159 if (!g_ascii_isdigit(*buf)((g_ascii_table[(guchar) (*buf)] & G_ASCII_DIGIT) != 0))
4160 return false0;
4161
4162 return true1;
4163}
4164
4165static ws_mempbrk_pattern pbrk_crlf;
4166/*
4167 * Given a tvbuff, an offset into the tvbuff, and a length that starts
4168 * at that offset (which may be -1 for "all the way to the end of the
4169 * tvbuff"), find the end of the (putative) line that starts at the
4170 * specified offset in the tvbuff, going no further than the specified
4171 * length.
4172 *
4173 * Return the length of the line (not counting the line terminator at
4174 * the end), or, if we don't find a line terminator:
4175 *
4176 * if "desegment" is true, return -1;
4177 *
4178 * if "desegment" is false, return the amount of data remaining in
4179 * the buffer.
4180 *
4181 * If "next_offset" is not NULL, set "*next_offset" to the offset of the
4182 * character past the line terminator, or past the end of the buffer if
4183 * we don't find a line terminator. (It's not set if we return -1.)
4184 */
4185int
4186tvb_find_line_end(tvbuff_t *tvb, const int offset, int len, int *next_offset, const bool_Bool desegment)
4187{
4188 int eob_offset;
4189 int eol_offset;
4190 int linelen;
4191 unsigned char found_needle = 0;
4192 static bool_Bool compiled = false0;
4193
4194 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4194, "tvb && tvb->initialized"
))))
;
4195
4196 if (len == -1) {
4197 len = _tvb_captured_length_remaining(tvb, offset);
4198 /* if offset is past the end of the tvbuff, len is now 0 */
4199 }
4200
4201 eob_offset = offset + len;
4202
4203 if (!compiled) {
4204 ws_mempbrk_compile(&pbrk_crlf, "\r\n");
4205 compiled = true1;
4206 }
4207
4208 /*
4209 * Look either for a CR or an LF.
4210 */
4211 eol_offset = tvb_ws_mempbrk_pattern_uint8(tvb, offset, len, &pbrk_crlf, &found_needle);
4212 if (eol_offset == -1) {
4213 /*
4214 * No CR or LF - line is presumably continued in next packet.
4215 */
4216 if (desegment) {
4217 /*
4218 * Tell our caller we saw no EOL, so they can
4219 * try to desegment and get the entire line
4220 * into one tvbuff.
4221 */
4222 return -1;
4223 } else {
4224 /*
4225 * Pretend the line runs to the end of the tvbuff.
4226 */
4227 linelen = eob_offset - offset;
4228 if (next_offset)
4229 *next_offset = eob_offset;
4230 }
4231 } else {
4232 /*
4233 * Find the number of bytes between the starting offset
4234 * and the CR or LF.
4235 */
4236 linelen = eol_offset - offset;
4237
4238 /*
4239 * Is it a CR?
4240 */
4241 if (found_needle == '\r') {
4242 /*
4243 * Yes - is it followed by an LF?
4244 */
4245 if (eol_offset + 1 >= eob_offset) {
4246 /*
4247 * Dunno - the next byte isn't in this
4248 * tvbuff.
4249 */
4250 if (desegment) {
4251 /*
4252 * We'll return -1, although that
4253 * runs the risk that if the line
4254 * really *is* terminated with a CR,
4255 * we won't properly dissect this
4256 * tvbuff.
4257 *
4258 * It's probably more likely that
4259 * the line ends with CR-LF than
4260 * that it ends with CR by itself.
4261 */
4262 return -1;
4263 }
4264 } else {
4265 /*
4266 * Well, we can at least look at the next
4267 * byte.
4268 */
4269 if (tvb_get_uint8(tvb, eol_offset + 1) == '\n') {
4270 /*
4271 * It's an LF; skip over the CR.
4272 */
4273 eol_offset++;
4274 }
4275 }
4276 }
4277
4278 /*
4279 * Return the offset of the character after the last
4280 * character in the line, skipping over the last character
4281 * in the line terminator.
4282 */
4283 if (next_offset)
4284 *next_offset = eol_offset + 1;
4285 }
4286 return linelen;
4287}
4288
4289static ws_mempbrk_pattern pbrk_crlf_dquote;
4290/*
4291 * Given a tvbuff, an offset into the tvbuff, and a length that starts
4292 * at that offset (which may be -1 for "all the way to the end of the
4293 * tvbuff"), find the end of the (putative) line that starts at the
4294 * specified offset in the tvbuff, going no further than the specified
4295 * length.
4296 *
4297 * However, treat quoted strings inside the buffer specially - don't
4298 * treat newlines in quoted strings as line terminators.
4299 *
4300 * Return the length of the line (not counting the line terminator at
4301 * the end), or the amount of data remaining in the buffer if we don't
4302 * find a line terminator.
4303 *
4304 * If "next_offset" is not NULL, set "*next_offset" to the offset of the
4305 * character past the line terminator, or past the end of the buffer if
4306 * we don't find a line terminator.
4307 */
4308int
4309tvb_find_line_end_unquoted(tvbuff_t *tvb, const int offset, int len, int *next_offset)
4310{
4311 int cur_offset, char_offset;
4312 bool_Bool is_quoted;
4313 unsigned char c = 0;
4314 int eob_offset;
4315 int linelen;
4316 static bool_Bool compiled = false0;
4317
4318 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4318, "tvb && tvb->initialized"
))))
;
4319
4320 if (len == -1)
4321 len = _tvb_captured_length_remaining(tvb, offset);
4322
4323 if (!compiled) {
4324 ws_mempbrk_compile(&pbrk_crlf_dquote, "\r\n\"");
4325 compiled = true1;
4326 }
4327
4328 /*
4329 * XXX - what if "len" is still -1, meaning "offset is past the
4330 * end of the tvbuff"?
4331 */
4332 eob_offset = offset + len;
4333
4334 cur_offset = offset;
4335 is_quoted = false0;
4336 for (;;) {
4337 /*
4338 * Is this part of the string quoted?
4339 */
4340 if (is_quoted) {
4341 /*
4342 * Yes - look only for the terminating quote.
4343 */
4344 char_offset = tvb_find_uint8(tvb, cur_offset, len,
4345 '"');
4346 } else {
4347 /*
4348 * Look either for a CR, an LF, or a '"'.
4349 */
4350 char_offset = tvb_ws_mempbrk_pattern_uint8(tvb, cur_offset, len, &pbrk_crlf_dquote, &c);
4351 }
4352 if (char_offset == -1) {
4353 /*
4354 * Not found - line is presumably continued in
4355 * next packet.
4356 * We pretend the line runs to the end of the tvbuff.
4357 */
4358 linelen = eob_offset - offset;
4359 if (next_offset)
4360 *next_offset = eob_offset;
4361 break;
4362 }
4363
4364 if (is_quoted) {
4365 /*
4366 * We're processing a quoted string.
4367 * We only looked for ", so we know it's a ";
4368 * as we're processing a quoted string, it's a
4369 * closing quote.
4370 */
4371 is_quoted = false0;
4372 } else {
4373 /*
4374 * OK, what is it?
4375 */
4376 if (c == '"') {
4377 /*
4378 * Un-quoted "; it begins a quoted
4379 * string.
4380 */
4381 is_quoted = true1;
4382 } else {
4383 /*
4384 * It's a CR or LF; we've found a line
4385 * terminator.
4386 *
4387 * Find the number of bytes between the
4388 * starting offset and the CR or LF.
4389 */
4390 linelen = char_offset - offset;
4391
4392 /*
4393 * Is it a CR?
4394 */
4395 if (c == '\r') {
4396 /*
4397 * Yes; is it followed by an LF?
4398 */
4399 if (char_offset + 1 < eob_offset &&
4400 tvb_get_uint8(tvb, char_offset + 1)
4401 == '\n') {
4402 /*
4403 * Yes; skip over the CR.
4404 */
4405 char_offset++;
4406 }
4407 }
4408
4409 /*
4410 * Return the offset of the character after
4411 * the last character in the line, skipping
4412 * over the last character in the line
4413 * terminator, and quit.
4414 */
4415 if (next_offset)
4416 *next_offset = char_offset + 1;
4417 break;
4418 }
4419 }
4420
4421 /*
4422 * Step past the character we found.
4423 */
4424 cur_offset = char_offset + 1;
4425 if (cur_offset >= eob_offset) {
4426 /*
4427 * The character we found was the last character
4428 * in the tvbuff - line is presumably continued in
4429 * next packet.
4430 * We pretend the line runs to the end of the tvbuff.
4431 */
4432 linelen = eob_offset - offset;
4433 if (next_offset)
4434 *next_offset = eob_offset;
4435 break;
4436 }
4437 }
4438 return linelen;
4439}
4440
4441/*
4442 * Copied from the mgcp dissector. (This function should be moved to /epan )
4443 * tvb_skip_wsp - Returns the position in tvb of the first non-whitespace
4444 * character following offset or offset + maxlength -1 whichever
4445 * is smaller.
4446 *
4447 * Parameters:
4448 * tvb - The tvbuff in which we are skipping whitespace.
4449 * offset - The offset in tvb from which we begin trying to skip whitespace.
4450 * maxlength - The maximum distance from offset that we may try to skip
4451 * whitespace.
4452 *
4453 * Returns: The position in tvb of the first non-whitespace
4454 * character following offset or offset + maxlength -1 whichever
4455 * is smaller.
4456 */
4457int
4458tvb_skip_wsp(tvbuff_t *tvb, const int offset, const int maxlength)
4459{
4460 int counter;
4461 int end, tvb_len;
4462 uint8_t tempchar;
4463
4464 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4464, "tvb && tvb->initialized"
))))
;
4465
4466 /* Get the length remaining */
4467 /*tvb_len = tvb_captured_length(tvb);*/
4468 tvb_len = tvb->length;
4469
4470 end = offset + maxlength;
4471 if (end >= tvb_len)
4472 {
4473 end = tvb_len;
4474 }
4475
4476 /* Skip past spaces, tabs, CRs and LFs until run out or meet something else */
4477 for (counter = offset;
4478 counter < end &&
4479 ((tempchar = tvb_get_uint8(tvb,counter)) == ' ' ||
4480 tempchar == '\t' || tempchar == '\r' || tempchar == '\n');
4481 counter++);
4482
4483 return (counter);
4484}
4485
4486int
4487tvb_skip_wsp_return(tvbuff_t *tvb, const int offset)
4488{
4489 int counter;
4490 uint8_t tempchar;
4491
4492 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4492, "tvb && tvb->initialized"
))))
;
4493
4494 for (counter = offset; counter > 0 &&
4495 ((tempchar = tvb_get_uint8(tvb,counter)) == ' ' ||
4496 tempchar == '\t' || tempchar == '\n' || tempchar == '\r'); counter--);
4497 counter++;
4498
4499 return (counter);
4500}
4501
4502int
4503tvb_skip_uint8(tvbuff_t *tvb, int offset, const int maxlength, const uint8_t ch)
4504{
4505 int end, tvb_len;
4506
4507 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4507, "tvb && tvb->initialized"
))))
;
4508
4509 /* Get the length remaining */
4510 /*tvb_len = tvb_captured_length(tvb);*/
4511 tvb_len = tvb->length;
4512
4513 end = offset + maxlength;
4514 if (end >= tvb_len)
4515 end = tvb_len;
4516
4517 while (offset < end) {
4518 uint8_t tempch = tvb_get_uint8(tvb, offset);
4519
4520 if (tempch != ch)
4521 break;
4522 offset++;
4523 }
4524
4525 return offset;
4526}
4527
4528static ws_mempbrk_pattern pbrk_whitespace;
4529
4530int tvb_get_token_len(tvbuff_t *tvb, const int offset, int len, int *next_offset, const bool_Bool desegment)
4531{
4532 int eob_offset;
4533 int eot_offset;
4534 int tokenlen;
4535 unsigned char found_needle = 0;
4536 static bool_Bool compiled = false0;
4537
4538 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4538, "tvb && tvb->initialized"
))))
;
4539
4540 if (len == -1) {
4541 len = _tvb_captured_length_remaining(tvb, offset);
4542 /* if offset is past the end of the tvbuff, len is now 0 */
4543 }
4544
4545 eob_offset = offset + len;
4546
4547 if (!compiled) {
4548 ws_mempbrk_compile(&pbrk_whitespace, " \r\n");
4549 compiled = true1;
4550 }
4551
4552 /*
4553 * Look either for a space, CR, or LF.
4554 */
4555 eot_offset = tvb_ws_mempbrk_pattern_uint8(tvb, offset, len, &pbrk_whitespace, &found_needle);
4556 if (eot_offset == -1) {
4557 /*
4558 * No space, CR or LF - token is presumably continued in next packet.
4559 */
4560 if (desegment) {
4561 /*
4562 * Tell our caller we saw no whitespace, so they can
4563 * try to desegment and get the entire line
4564 * into one tvbuff.
4565 */
4566 return -1;
4567 }
4568 else {
4569 /*
4570 * Pretend the token runs to the end of the tvbuff.
4571 */
4572 tokenlen = eob_offset - offset;
4573 if (next_offset)
4574 *next_offset = eob_offset;
4575 }
4576 }
4577 else {
4578 /*
4579 * Find the number of bytes between the starting offset
4580 * and the space, CR or LF.
4581 */
4582 tokenlen = eot_offset - offset;
4583
4584 /*
4585 * Return the offset of the character after the last
4586 * character in the line, skipping over the last character
4587 * in the line terminator.
4588 */
4589 if (next_offset)
4590 *next_offset = eot_offset + 1;
4591 }
4592 return tokenlen;
4593}
4594
4595/*
4596 * Format a bunch of data from a tvbuff as bytes, returning a pointer
4597 * to the string with the formatted data, with "punct" as a byte
4598 * separator.
4599 */
4600char *
4601tvb_bytes_to_str_punct(wmem_allocator_t *scope, tvbuff_t *tvb, const int offset, const int len, const char punct)
4602{
4603 DISSECTOR_ASSERT(len > 0)((void) ((len > 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4603, "len > 0"
))))
;
4604 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)
;
4605}
4606
4607/*
4608 * Given a wmem scope, a tvbuff, an offset, a length, an input digit
4609 * set, and a boolean indicator, fetch BCD-encoded digits from a
4610 * tvbuff starting from either the low or high half byte of the
4611 * first byte depending on the boolean indicator (true means "start
4612 * with the high half byte, ignoring the low half byte", and false
4613 * means "start with the low half byte and proceed to the high half
4614 * byte), formating the digits into characters according to the
4615 * input digit set, and return a pointer to a UTF-8 string, allocated
4616 * using the wmem scope. A nibble of 0xf is considered a 'filler'
4617 * and will end the conversion. Similarly if odd is set the last
4618 * high nibble will be omitted. (Note that if both skip_first and
4619 * odd are true, then both the first and last semi-octet are skipped,
4620 * i.e. an even number of nibbles are considered.)
4621 */
4622char *
4623tvb_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)
4624{
4625 const uint8_t *ptr;
4626 int i = 0;
4627 char *digit_str;
4628 uint8_t octet, nibble;
4629
4630 DISSECTOR_ASSERT(tvb && tvb->initialized)((void) ((tvb && tvb->initialized) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4630, "tvb && tvb->initialized"
))))
;
4631
4632 if (len == -1) {
4633 /*
4634 * Run to the end of the captured data.
4635 *
4636 * XXX - captured, or total?
4637 */
4638 /*length = tvb_captured_length(tvb);*/
4639 len = tvb->length;
4640 if (len < offset) {
4641 return (char *)"";
4642 }
4643 len -= offset;
4644 }
4645
4646 ptr = ensure_contiguous(tvb, offset, len);
4647
4648 /*
4649 * XXX - map illegal digits (digits that map to 0) to REPLACEMENT
4650 * CHARACTER, and have all the tables in epan/tvbuff.c use 0 rather
4651 * than '?'?
4652 */
4653 digit_str = (char *)wmem_alloc(scope, len*2 + 1);
4654
4655 while (len > 0) {
4656 octet = *ptr;
4657 if (!skip_first) {
4658 if (bigendian) {
4659 nibble = (octet >> 4) & 0x0f;
4660 } else {
4661 nibble = octet & 0x0f;
4662 }
4663 if (nibble == 0x0f) {
4664 /*
4665 * Stop digit.
4666 */
4667 break;
4668 }
4669 digit_str[i] = dgt->out[nibble];
4670 i++;
4671 }
4672 skip_first = false0;
4673
4674 /*
4675 * unpack second value in byte
4676 */
4677 if (bigendian) {
4678 nibble = octet & 0x0f;
4679 } else {
4680 nibble = octet >> 4;
4681 }
4682
4683 if (nibble == 0x0f) {
4684 /*
4685 * This is the stop digit or a filler digit. Ignore
4686 * it.
4687 */
4688 break;
4689 }
4690 if ((len == 1) && (odd == true1 )){
4691 /* Last octet, skip last high nibble in case of odd number of digits */
4692 break;
4693 }
4694 digit_str[i] = dgt->out[nibble];
4695 i++;
4696
4697 ptr++;
4698 len--;
4699 }
4700 digit_str[i] = '\0';
4701 return digit_str;
4702}
4703
4704/* XXXX Fix me - needs odd indicator added */
4705const char *
4706tvb_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)
4707{
4708 if (!dgt)
4709 dgt = &Dgt0_9_bcd;
4710
4711 return tvb_get_bcd_string(scope, tvb, offset, len, dgt, skip_first, false0, false0);
4712}
4713
4714const char *
4715tvb_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)
4716{
4717 if (!dgt)
4718 dgt = &Dgt0_9_bcd;
4719
4720 return tvb_get_bcd_string(scope, tvb, offset, len, dgt, skip_first, false0, true1);
4721}
4722
4723/*
4724 * Format a bunch of data from a tvbuff as bytes, returning a pointer
4725 * to the string with the formatted data.
4726 */
4727char *tvb_bytes_to_str(wmem_allocator_t *allocator, tvbuff_t *tvb,
4728 const int offset, const int len)
4729{
4730 DISSECTOR_ASSERT(len > 0)((void) ((len > 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/tvbuff.c", 4730, "len > 0"
))))
;
4731 return bytes_to_str(allocator, ensure_contiguous(tvb, offset, len), len)bytes_to_str_maxlen(allocator, ensure_contiguous(tvb, offset,
len), len, 36)
;
4732}
4733
4734/* Find a needle tvbuff within a haystack tvbuff. */
4735int
4736tvb_find_tvb(tvbuff_t *haystack_tvb, tvbuff_t *needle_tvb, const int haystack_offset)
4737{
4738 unsigned haystack_abs_offset = 0, haystack_abs_length = 0;
4739 const uint8_t *haystack_data;
4740 const uint8_t *needle_data;
4741 const unsigned needle_len = needle_tvb->length;
4742 const uint8_t *location;
4743
4744 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", 4744, "haystack_tvb && haystack_tvb->initialized"
))))
;
4745
4746 if (haystack_tvb->length < 1 || needle_tvb->length < 1) {
4747 return -1;
4748 }
4749
4750 /* Get pointers to the tvbuffs' data. */
4751 haystack_data = ensure_contiguous(haystack_tvb, 0, -1);
4752 needle_data = ensure_contiguous(needle_tvb, 0, -1);
4753
4754 check_offset_length(haystack_tvb, haystack_offset, -1,
4755 &haystack_abs_offset, &haystack_abs_length);
4756
4757 location = ws_memmem(haystack_data + haystack_abs_offset, haystack_abs_length,
4758 needle_data, needle_len);
4759
4760 if (location) {
4761 return (int) (location - haystack_data);
4762 }
4763
4764 return -1;
4765}
4766
4767int
4768tvb_raw_offset(tvbuff_t *tvb)
4769{
4770 return ((tvb->raw_offset==-1) ? (tvb->raw_offset = tvb_offset_from_real_beginning(tvb)) : tvb->raw_offset);
4771}
4772
4773void
4774tvb_set_fragment(tvbuff_t *tvb)
4775{
4776 tvb->flags |= TVBUFF_FRAGMENT0x00000001;
4777}
4778
4779struct tvbuff *
4780tvb_get_ds_tvb(tvbuff_t *tvb)
4781{
4782 return(tvb->ds_tvb);
4783}
4784
4785unsigned
4786tvb_get_varint(tvbuff_t *tvb, unsigned offset, unsigned maxlen, uint64_t *value, const unsigned encoding)
4787{
4788 *value = 0;
4789
4790 switch (encoding & ENC_VARINT_MASK(0x00000002|0x00000004|0x00000008|0x00000010)) {
4791 case ENC_VARINT_PROTOBUF0x00000002:
4792 {
4793 unsigned i;
4794 uint64_t b; /* current byte */
4795
4796 for (i = 0; ((i < FT_VARINT_MAX_LEN10) && (i < maxlen)); ++i) {
4797 b = tvb_get_uint8(tvb, offset++);
4798 *value |= ((b & 0x7F) << (i * 7)); /* add lower 7 bits to val */
4799
4800 if (b < 0x80) {
4801 /* end successfully becauseof last byte's msb(most significant bit) is zero */
4802 return i + 1;
4803 }
4804 }
4805 break;
4806 }
4807
4808 case ENC_VARINT_ZIGZAG0x00000008:
4809 {
4810 unsigned i;
4811 uint64_t b; /* current byte */
4812
4813 for (i = 0; ((i < FT_VARINT_MAX_LEN10) && (i < maxlen)); ++i) {
4814 b = tvb_get_uint8(tvb, offset++);
4815 *value |= ((b & 0x7F) << (i * 7)); /* add lower 7 bits to val */
4816
4817 if (b < 0x80) {
4818 /* end successfully becauseof last byte's msb(most significant bit) is zero */
4819 *value = (*value >> 1) ^ ((*value & 1) ? -1 : 0);
4820 return i + 1;
4821 }
4822 }
4823 break;
4824 }
4825
4826 case ENC_VARINT_SDNV0x00000010:
4827 {
4828 /* Decodes similar to protobuf but in MSByte order */
4829 unsigned i;
4830 uint64_t b; /* current byte */
4831
4832 for (i = 0; ((i < FT_VARINT_MAX_LEN10) && (i < maxlen)); ++i) {
4833 b = tvb_get_uint8(tvb, offset++);
4834 if ((i == 9) && (*value >= UINT64_C(1)1UL<<(64-7))) {
4835 // guaranteed overflow, not valid SDNV
4836 return 0;
4837 }
4838 *value <<= 7;
4839 *value |= (b & 0x7F); /* add lower 7 bits to val */
4840
4841 if (b < 0x80) {
4842 /* end successfully because of last byte's msb(most significant bit) is zero */
4843 return i + 1;
4844 }
4845 }
4846 break;
4847 }
4848
4849 case ENC_VARINT_QUIC0x00000004:
4850 {
4851 /* calculate variable length */
4852 *value = tvb_get_uint8(tvb, offset);
4853 switch((*value) >> 6) {
4854 case 0: /* 0b00 => 1 byte length (6 bits Usable) */
4855 (*value) &= 0x3F;
4856 return 1;
4857 case 1: /* 0b01 => 2 bytes length (14 bits Usable) */
4858 *value = tvb_get_ntohs(tvb, offset) & 0x3FFF;
4859 return 2;
4860 case 2: /* 0b10 => 4 bytes length (30 bits Usable) */
4861 *value = tvb_get_ntohl(tvb, offset) & 0x3FFFFFFF;
4862 return 4;
4863 case 3: /* 0b11 => 8 bytes length (62 bits Usable) */
4864 *value = tvb_get_ntoh64(tvb, offset) & UINT64_C(0x3FFFFFFFFFFFFFFF)0x3FFFFFFFFFFFFFFFUL;
4865 return 8;
4866 default: /* No Possible */
4867 ws_assert_not_reached()ws_log_fatal_full("", LOG_LEVEL_ERROR, "epan/tvbuff.c", 4867,
__func__, "assertion \"not reached\" failed")
;
4868 break;
4869 }
4870 break;
4871 }
4872
4873 default:
4874 DISSECTOR_ASSERT_NOT_REACHED()(proto_report_dissector_bug("%s:%u: failed assertion \"DISSECTOR_ASSERT_NOT_REACHED\""
, "epan/tvbuff.c", 4874))
;
4875 }
4876
4877 return 0; /* 10 bytes scanned, but no bytes' msb is zero */
4878}
4879
4880/*
4881 * Editor modelines - https://www.wireshark.org/tools/modelines.html
4882 *
4883 * Local variables:
4884 * c-basic-offset: 8
4885 * tab-width: 8
4886 * indent-tabs-mode: t
4887 * End:
4888 *
4889 * vi: set shiftwidth=8 tabstop=8 noexpandtab:
4890 * :indentSize=8:tabSize=8:noTabs=false:
4891 */