Bug Summary

File:builds/wireshark/wireshark/epan/reassemble.c
Warning:line 1995, column 6
Potential leak of memory pointed to by 'data'

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 reassemble.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-22/lib/clang/22 -isystem /usr/include/glib-2.0 -isystem /usr/lib/x86_64-linux-gnu/glib-2.0/include -isystem /builds/wireshark/wireshark/epan -isystem /builds/wireshark/wireshark/build/epan -isystem /usr/include/mit-krb5 -isystem /usr/include/lua5.5 -isystem /usr/include/libxml2 -D CARES_NO_DEPRECATED -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-22/lib/clang/22/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/16/../../../../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-nonliteral -std=gnu17 -ferror-limit 19 -fvisibility=hidden -fwrapv -fwrapv-pointer -fstrict-flex-arrays=3 -stack-protector 2 -fstack-clash-protection -fcf-protection=full -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fexceptions -fcolor-diagnostics -analyzer-output=html -faddrsig -fdwarf2-cfi-asm -o /builds/wireshark/wireshark/sbout/2026-07-07-100348-3595-1 -x c /builds/wireshark/wireshark/epan/reassemble.c
1/* reassemble.c
2 * Routines for {fragment,segment} reassembly
3 *
4 * Wireshark - Network traffic analyzer
5 * By Gerald Combs <gerald@wireshark.org>
6 * Copyright 1998 Gerald Combs
7 *
8 * SPDX-License-Identifier: GPL-2.0-or-later
9 */
10
11#include "config.h"
12
13#include <string.h>
14
15#include <epan/packet.h>
16#include <epan/exceptions.h>
17#include <epan/reassemble.h>
18#include <epan/tvbuff-int.h>
19
20#include <wsutil/str_util.h>
21#include <wsutil/ws_assert.h>
22
23/*
24 * Functions for reassembly tables where the endpoint addresses, and a
25 * fragment ID, are used as the key.
26 */
27typedef struct _fragment_addresses_key {
28 address src;
29 address dst;
30 uint32_t id;
31} fragment_addresses_key;
32
33static GList* reassembly_table_list;
34
35static unsigned
36fragment_addresses_hash(const void *k)
37{
38 const fragment_addresses_key* key = (const fragment_addresses_key*) k;
39 unsigned hash_val;
40/*
41 int i;
42*/
43
44 hash_val = 0;
45
46/* More than likely: in most captures src and dst addresses are the
47 same, and would hash the same.
48 We only use id as the hash as an optimization.
49
50 for (i = 0; i < key->src.len; i++)
51 hash_val += key->src.data[i];
52 for (i = 0; i < key->dst.len; i++)
53 hash_val += key->dst.data[i];
54*/
55
56 hash_val += key->id;
57
58 return hash_val;
59}
60
61static int
62fragment_addresses_equal(const void *k1, const void *k2)
63{
64 const fragment_addresses_key* key1 = (const fragment_addresses_key*) k1;
65 const fragment_addresses_key* key2 = (const fragment_addresses_key*) k2;
66
67 /*
68 * key.id is the first item to compare since it's the item most
69 * likely to differ between sessions, thus short-circuiting
70 * the comparison of addresses.
71 */
72 return (key1->id == key2->id) &&
73 (addresses_equal(&key1->src, &key2->src)) &&
74 (addresses_equal(&key1->dst, &key2->dst));
75}
76
77/*
78 * Create a fragment key for temporary use; it can point to non-
79 * persistent data, and so must only be used to look up and
80 * delete entries, not to add them.
81 */
82static void *
83fragment_addresses_temporary_key(const packet_info *pinfo, const uint32_t id,
84 const void *data _U___attribute__((unused)))
85{
86 fragment_addresses_key *key = g_slice_new(fragment_addresses_key)((fragment_addresses_key*) g_slice_alloc ((sizeof (fragment_addresses_key
) > 0 ? sizeof (fragment_addresses_key) : 1)))
;
87
88 /*
89 * Do a shallow copy of the addresses.
90 */
91 copy_address_shallow(&key->src, &pinfo->src);
92 copy_address_shallow(&key->dst, &pinfo->dst);
93 key->id = id;
94
95 return (void *)key;
96}
97
98/*
99 * Create a fragment key for permanent use; it must point to persistent
100 * data, so that it can be used to add entries.
101 */
102static void *
103fragment_addresses_persistent_key(const packet_info *pinfo, const uint32_t id,
104 const void *data _U___attribute__((unused)))
105{
106 fragment_addresses_key *key = g_slice_new(fragment_addresses_key)((fragment_addresses_key*) g_slice_alloc ((sizeof (fragment_addresses_key
) > 0 ? sizeof (fragment_addresses_key) : 1)))
;
107
108 /*
109 * Do a deep copy of the addresses.
110 */
111 copy_address(&key->src, &pinfo->src);
112 copy_address(&key->dst, &pinfo->dst);
113 key->id = id;
114
115 return (void *)key;
116}
117
118static void
119fragment_addresses_free_temporary_key(void *ptr)
120{
121 fragment_addresses_key *key = (fragment_addresses_key *)ptr;
122 g_slice_free(fragment_addresses_key, key)do { if (1) g_slice_free1 (sizeof (fragment_addresses_key), (
key)); else (void) ((fragment_addresses_key*) 0 == (key)); } while
(0)
;
123}
124
125static void
126fragment_addresses_free_persistent_key(void *ptr)
127{
128 fragment_addresses_key *key = (fragment_addresses_key *)ptr;
129
130 if(key){
131 /*
132 * Free up the copies of the addresses from the old key.
133 */
134 free_address(&key->src);
135 free_address(&key->dst);
136
137 g_slice_free(fragment_addresses_key, key)do { if (1) g_slice_free1 (sizeof (fragment_addresses_key), (
key)); else (void) ((fragment_addresses_key*) 0 == (key)); } while
(0)
;
138 }
139}
140
141const reassembly_table_functions
142addresses_reassembly_table_functions = {
143 fragment_addresses_hash,
144 fragment_addresses_equal,
145 fragment_addresses_temporary_key,
146 fragment_addresses_persistent_key,
147 fragment_addresses_free_temporary_key,
148 fragment_addresses_free_persistent_key
149};
150
151/*
152 * Functions for reassembly tables where the endpoint addresses and ports,
153 * and a fragment ID, are used as the key.
154 */
155typedef struct _fragment_addresses_ports_key {
156 address src_addr;
157 address dst_addr;
158 uint32_t src_port;
159 uint32_t dst_port;
160 uint32_t id;
161} fragment_addresses_ports_key;
162
163static unsigned
164fragment_addresses_ports_hash(const void *k)
165{
166 const fragment_addresses_ports_key* key = (const fragment_addresses_ports_key*) k;
167 unsigned hash_val;
168/*
169 int i;
170*/
171
172 hash_val = 0;
173
174/* More than likely: in most captures src and dst addresses and ports
175 are the same, and would hash the same.
176 We only use id as the hash as an optimization.
177
178 for (i = 0; i < key->src.len; i++)
179 hash_val += key->src_addr.data[i];
180 for (i = 0; i < key->dst.len; i++)
181 hash_val += key->dst_addr.data[i];
182 hash_val += key->src_port;
183 hash_val += key->dst_port;
184*/
185
186 hash_val += key->id;
187
188 return hash_val;
189}
190
191static int
192fragment_addresses_ports_equal(const void *k1, const void *k2)
193{
194 const fragment_addresses_ports_key* key1 = (const fragment_addresses_ports_key*) k1;
195 const fragment_addresses_ports_key* key2 = (const fragment_addresses_ports_key*) k2;
196
197 /*
198 * key.id is the first item to compare since it's the item most
199 * likely to differ between sessions, thus short-circuiting
200 * the comparison of addresses and ports.
201 */
202 return (key1->id == key2->id) &&
203 (addresses_equal(&key1->src_addr, &key2->src_addr)) &&
204 (addresses_equal(&key1->dst_addr, &key2->dst_addr)) &&
205 (key1->src_port == key2->src_port) &&
206 (key1->dst_port == key2->dst_port);
207}
208
209/*
210 * Create a fragment key for temporary use; it can point to non-
211 * persistent data, and so must only be used to look up and
212 * delete entries, not to add them.
213 */
214static void *
215fragment_addresses_ports_temporary_key(const packet_info *pinfo, const uint32_t id,
216 const void *data _U___attribute__((unused)))
217{
218 fragment_addresses_ports_key *key = g_slice_new(fragment_addresses_ports_key)((fragment_addresses_ports_key*) g_slice_alloc ((sizeof (fragment_addresses_ports_key
) > 0 ? sizeof (fragment_addresses_ports_key) : 1)))
;
219
220 /*
221 * Do a shallow copy of the addresses.
222 */
223 copy_address_shallow(&key->src_addr, &pinfo->src);
224 copy_address_shallow(&key->dst_addr, &pinfo->dst);
225 key->src_port = pinfo->srcport;
226 key->dst_port = pinfo->destport;
227 key->id = id;
228
229 return (void *)key;
230}
231
232/*
233 * Create a fragment key for permanent use; it must point to persistent
234 * data, so that it can be used to add entries.
235 */
236static void *
237fragment_addresses_ports_persistent_key(const packet_info *pinfo,
238 const uint32_t id, const void *data _U___attribute__((unused)))
239{
240 fragment_addresses_ports_key *key = g_slice_new(fragment_addresses_ports_key)((fragment_addresses_ports_key*) g_slice_alloc ((sizeof (fragment_addresses_ports_key
) > 0 ? sizeof (fragment_addresses_ports_key) : 1)))
;
241
242 /*
243 * Do a deep copy of the addresses.
244 */
245 copy_address(&key->src_addr, &pinfo->src);
246 copy_address(&key->dst_addr, &pinfo->dst);
247 key->src_port = pinfo->srcport;
248 key->dst_port = pinfo->destport;
249 key->id = id;
250
251 return (void *)key;
252}
253
254static void
255fragment_addresses_ports_free_temporary_key(void *ptr)
256{
257 fragment_addresses_ports_key *key = (fragment_addresses_ports_key *)ptr;
258 g_slice_free(fragment_addresses_ports_key, key)do { if (1) g_slice_free1 (sizeof (fragment_addresses_ports_key
), (key)); else (void) ((fragment_addresses_ports_key*) 0 == (
key)); } while (0)
;
259}
260
261static void
262fragment_addresses_ports_free_persistent_key(void *ptr)
263{
264 fragment_addresses_ports_key *key = (fragment_addresses_ports_key *)ptr;
265
266 if(key){
267 /*
268 * Free up the copies of the addresses from the old key.
269 */
270 free_address(&key->src_addr);
271 free_address(&key->dst_addr);
272
273 g_slice_free(fragment_addresses_ports_key, key)do { if (1) g_slice_free1 (sizeof (fragment_addresses_ports_key
), (key)); else (void) ((fragment_addresses_ports_key*) 0 == (
key)); } while (0)
;
274 }
275}
276
277const reassembly_table_functions
278addresses_ports_reassembly_table_functions = {
279 fragment_addresses_ports_hash,
280 fragment_addresses_ports_equal,
281 fragment_addresses_ports_temporary_key,
282 fragment_addresses_ports_persistent_key,
283 fragment_addresses_ports_free_temporary_key,
284 fragment_addresses_ports_free_persistent_key
285};
286
287typedef struct _reassembled_key {
288 uint32_t id;
289 uint32_t frame;
290} reassembled_key;
291
292static int
293reassembled_equal(const void *k1, const void *k2)
294{
295 const reassembled_key* key1 = (const reassembled_key*) k1;
296 const reassembled_key* key2 = (const reassembled_key*) k2;
297
298 /*
299 * We assume that the frame numbers are unlikely to be equal,
300 * so we check them first.
301 */
302 return key1->frame == key2->frame && key1->id == key2->id;
303}
304
305static unsigned
306reassembled_hash(const void *k)
307{
308 const reassembled_key* key = (const reassembled_key*) k;
309
310 return key->frame;
311}
312
313static void
314reassembled_key_free(void *ptr)
315{
316 g_slice_free(reassembled_key, (reassembled_key *)ptr)do { if (1) g_slice_free1 (sizeof (reassembled_key), ((reassembled_key
*)ptr)); else (void) ((reassembled_key*) 0 == ((reassembled_key
*)ptr)); } while (0)
;
317}
318
319/* --------------fragment_item functions ----------- */
320static fragment_item*
321new_fragment_item(uint32_t frame, uint32_t offset, uint32_t len)
322{
323 fragment_item *fd;
324
325 fd = g_slice_new(fragment_item)((fragment_item*) g_slice_alloc ((sizeof (fragment_item) >
0 ? sizeof (fragment_item) : 1)))
;
326 fd->next = NULL((void*)0);
327 fd->flags = 0;
328 fd->frame = frame;
329 fd->offset = offset;
330 fd->len = len;
331 fd->tvb_data = NULL((void*)0);
332
333 return fd;
334}
335
336static void
337fragment_item_free_tvb(fragment_item *fd_i)
338{
339 /* If this is a subset of the tvb created for the head after
340 * dissembly, don't free it (that would cause memory errors;
341 * the parent will be freed later.) */
342 if (fd_i->flags & FD_SUBSET_TVB0x0020)
343 fd_i->flags &= ~FD_SUBSET_TVB0x0020;
344 else if (fd_i->tvb_data)
345 tvb_free(fd_i->tvb_data);
346
347 fd_i->tvb_data=NULL((void*)0);
348}
349
350/* Returns the pointer to the next item so that the list can be freed. */
351static fragment_item*
352fragment_item_free(fragment_item *fd_i)
353{
354 fragment_item *fd_next = fd_i->next;
355 fragment_item_free_tvb(fd_i);
356 g_slice_free(fragment_item, fd_i)do { if (1) g_slice_free1 (sizeof (fragment_item), (fd_i)); else
(void) ((fragment_item*) 0 == (fd_i)); } while (0)
;
357 return fd_next;
358}
359
360/* ------------------------- */
361static fragment_head *new_head(const uint32_t flags)
362{
363 fragment_head *fd_head;
364 /* If head/first structure in list only holds no other data than
365 * 'datalen' then we don't have to change the head of the list
366 * even if we want to keep it sorted
367 */
368 fd_head=g_slice_new0(fragment_head)((fragment_head*) g_slice_alloc0 ((sizeof (fragment_head) >
0 ? sizeof (fragment_head) : 1)))
;
369
370 fd_head->flags=flags;
371 return fd_head;
372}
373
374/*
375 * For a reassembled-packet hash table entry, free the fragment data
376 * to which the value refers. (The key is freed by reassembled_key_free.)
377 */
378static void
379free_fd_head(fragment_head *fd_head)
380{
381 fragment_item *fd_i;
382
383 if (fd_head->flags & FD_SUBSET_TVB0x0020)
384 fd_head->tvb_data = NULL((void*)0);
385 if (fd_head->tvb_data)
386 tvb_free(fd_head->tvb_data);
387 fd_i = fd_head->next;
388 while (fd_i != NULL((void*)0)) {
389 fd_i = fragment_item_free(fd_i);
390 }
391 g_slice_free(fragment_head, fd_head)do { if (1) g_slice_free1 (sizeof (fragment_head), (fd_head))
; else (void) ((fragment_head*) 0 == (fd_head)); } while (0)
;
392}
393
394static void
395unref_fd_head(void *data)
396{
397 fragment_head *fd_head = (fragment_head *) data;
398 fd_head->ref_count--;
399
400 if (fd_head->ref_count == 0) {
401 free_fd_head(fd_head);
402 }
403}
404
405/*
406 * For a fragment hash table entry, free the associated fragments.
407 * The entry value (fd_chain) is freed herein and the entry is freed
408 * when the key freeing routine is called (as a consequence of returning
409 * true from this function).
410 */
411static gboolean
412free_all_fragments(void *key_arg _U___attribute__((unused)), void *value, void *user_data _U___attribute__((unused)))
413{
414 fragment_head *fd_head;
415
416 /* g_hash_table_new_full() was used to supply a function
417 * to free the key and anything to which it points
418 */
419 fd_head = (fragment_head *)value;
420 free_fd_head(fd_head);
421
422 return TRUE(!(0));
423}
424
425static void
426reassembled_table_insert(GHashTable *reassembled_table, reassembled_key *key, fragment_head *fd_head)
427{
428 fragment_head *old_fd_head;
429 fd_head->ref_count++;
430 if ((old_fd_head = g_hash_table_lookup(reassembled_table, key)) != NULL((void*)0)) {
431 if (old_fd_head->ref_count == 1) {
432 /* We're replacing the last entry in the reassembled
433 * table for an old reassembly. Does it have a tvb?
434 * We might still be using that tvb's memory for an
435 * address via set_address_tvb(). (See #19094.)
436 */
437 if (old_fd_head->tvb_data && fd_head->tvb_data) {
438 /* Free it when the new tvb is freed */
439 tvb_set_child_real_data_tvbuff(fd_head->tvb_data, old_fd_head->tvb_data);
440 }
441 /* XXX: Set the old data to NULL regardless. If we
442 * have old data but not new data, that is odd (we're
443 * replacing a reassembly with tvb data with something
444 * with no tvb data, possibly because a zero length or
445 * null tvb was passed into a defragment function,
446 * which is a dissector bug.)
447 * This leaks the tvb data if we couldn't add it to
448 * a new tvb's chain, but we might not be able to free
449 * it yet if set_address_tvb() was used.
450 */
451 old_fd_head->tvb_data = NULL((void*)0);
452 }
453 }
454 g_hash_table_insert(reassembled_table, key, fd_head);
455}
456
457typedef struct register_reassembly_table {
458 reassembly_table *table;
459 const reassembly_table_functions *funcs;
460} register_reassembly_table_t;
461
462/*
463 * Register a reassembly table.
464 */
465void
466reassembly_table_register(reassembly_table *table,
467 const reassembly_table_functions *funcs)
468{
469 register_reassembly_table_t* reg_table;
470
471 DISSECTOR_ASSERT(table)((void) ((table) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/reassemble.c", 471, "table"))))
;
472 DISSECTOR_ASSERT(funcs)((void) ((funcs) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/reassemble.c", 472, "funcs"))))
;
473
474 reg_table = g_new(register_reassembly_table_t,1)((register_reassembly_table_t *) g_malloc_n ((1), sizeof (register_reassembly_table_t
)))
;
475
476 reg_table->table = table;
477 reg_table->funcs = funcs;
478
479 reassembly_table_list = g_list_prepend(reassembly_table_list, reg_table);
480}
481
482/*
483 * Initialize a reassembly table, with specified functions.
484 */
485void
486reassembly_table_init(reassembly_table *table,
487 const reassembly_table_functions *funcs)
488{
489 if (table->temporary_key_func == NULL((void*)0))
490 table->temporary_key_func = funcs->temporary_key_func;
491 if (table->persistent_key_func == NULL((void*)0))
492 table->persistent_key_func = funcs->persistent_key_func;
493 if (table->free_temporary_key_func == NULL((void*)0))
494 table->free_temporary_key_func = funcs->free_temporary_key_func;
495 if (table->fragment_table != NULL((void*)0)) {
496 /*
497 * The fragment hash table exists.
498 *
499 * Remove all entries and free fragment data for each entry.
500 *
501 * The keys, and anything to which they point, are freed by
502 * calling the table's key freeing function. The values
503 * are freed in free_all_fragments().
504 */
505 g_hash_table_foreach_remove(table->fragment_table,
506 free_all_fragments, NULL((void*)0));
507 } else {
508 /* The fragment table does not exist. Create it */
509 table->fragment_table = g_hash_table_new_full(funcs->hash_func,
510 funcs->equal_func, funcs->free_persistent_key_func, NULL((void*)0));
511 }
512
513 if (table->reassembled_table != NULL((void*)0)) {
514 /*
515 * The reassembled-packet hash table exists.
516 *
517 * Remove all entries and free reassembled packet
518 * data and key for each entry.
519 */
520 g_hash_table_remove_all(table->reassembled_table);
521 } else {
522 /* The fragment table does not exist. Create it */
523 table->reassembled_table = g_hash_table_new_full(reassembled_hash,
524 reassembled_equal, reassembled_key_free, unref_fd_head);
525 }
526}
527
528/*
529 * Destroy a reassembly table.
530 */
531void
532reassembly_table_destroy(reassembly_table *table)
533{
534 /*
535 * Clear the function pointers.
536 */
537 table->temporary_key_func = NULL((void*)0);
538 table->persistent_key_func = NULL((void*)0);
539 table->free_temporary_key_func = NULL((void*)0);
540 if (table->fragment_table != NULL((void*)0)) {
541 /*
542 * The fragment hash table exists.
543 *
544 * Remove all entries and free fragment data for each entry.
545 *
546 * The keys, and anything to which they point, are freed by
547 * calling the table's key freeing function. The values
548 * are freed in free_all_fragments().
549 */
550 g_hash_table_foreach_remove(table->fragment_table,
551 free_all_fragments, NULL((void*)0));
552
553 /*
554 * Now destroy the hash table.
555 */
556 g_hash_table_destroy(table->fragment_table);
557 table->fragment_table = NULL((void*)0);
558 }
559 if (table->reassembled_table != NULL((void*)0)) {
560 /*
561 * The reassembled-packet hash table exists.
562 *
563 * Remove all entries and free reassembled packet
564 * data and key for each entry.
565 */
566
567 g_hash_table_remove_all(table->reassembled_table);
568
569 /*
570 * Now destroy the hash table.
571 */
572 g_hash_table_destroy(table->reassembled_table);
573 table->reassembled_table = NULL((void*)0);
574 }
575}
576
577/*
578 * Look up an fd_head in the fragment table, optionally returning the key
579 * for it.
580 */
581static fragment_head *
582lookup_fd_head(reassembly_table *table, const packet_info *pinfo,
583 const uint32_t id, const void *data, void * *orig_keyp)
584{
585 void *key;
586 void *value;
587
588 /* Create key to search hash with */
589 key = table->temporary_key_func(pinfo, id, data);
590
591 /*
592 * Look up the reassembly in the fragment table.
593 */
594 if (!g_hash_table_lookup_extended(table->fragment_table, key, orig_keyp,
595 &value))
596 value = NULL((void*)0);
597 /* Free the key */
598 table->free_temporary_key_func(key);
599
600 return (fragment_head *)value;
601}
602
603/*
604 * Insert an fd_head into the fragment table, and return the key used.
605 */
606static void *
607insert_fd_head(reassembly_table *table, fragment_head *fd_head,
608 const packet_info *pinfo, const uint32_t id, const void *data)
609{
610 void *key;
611
612 /*
613 * We're going to use the key to insert the fragment,
614 * so make a persistent version of it.
615 */
616 key = table->persistent_key_func(pinfo, id, data);
617 g_hash_table_insert(table->fragment_table, key, fd_head);
618 return key;
619}
620
621/* This function cleans up the stored state and removes the reassembly data and
622 * (with one exception) all allocated memory for matching reassembly.
623 *
624 * The exception is :
625 * If the PDU was already completely reassembled, then the tvbuff containing the
626 * reassembled data WILL NOT be free()d, and the pointer to that tvbuff will be
627 * returned.
628 * Othervise the function will return NULL.
629 *
630 * So, if you call fragment_delete and it returns non-NULL, YOU are responsible
631 * to tvb_free() that tvbuff.
632 */
633tvbuff_t *
634fragment_delete(reassembly_table *table, const packet_info *pinfo,
635 const uint32_t id, const void *data)
636{
637 fragment_head *fd_head;
638 fragment_item *fd;
639 tvbuff_t *fd_tvb_data=NULL((void*)0);
640 void *key;
641
642 fd_head = lookup_fd_head(table, pinfo, id, data, &key);
643 if(fd_head==NULL((void*)0)){
644 /* We do not recognize this as a PDU we have seen before. return */
645 return NULL((void*)0);
646 }
647
648 fd_tvb_data=fd_head->tvb_data;
649 /* loop over all partial fragments and free any tvbuffs */
650 fd = fd_head->next;
651 while (fd != NULL((void*)0)) {
652 fd = fragment_item_free(fd);
653 }
654 g_slice_free(fragment_head, fd_head)do { if (1) g_slice_free1 (sizeof (fragment_head), (fd_head))
; else (void) ((fragment_head*) 0 == (fd_head)); } while (0)
;
655 g_hash_table_remove(table->fragment_table, key);
656
657 return fd_tvb_data;
658}
659
660/* This function is used to check if there is partial or completed reassembly state
661 * matching this packet. I.e. Is there reassembly going on or not for this packet?
662 */
663fragment_head *
664fragment_get(reassembly_table *table, const packet_info *pinfo,
665 const uint32_t id, const void *data)
666{
667 return lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
668}
669
670fragment_head *
671fragment_get_reassembled_id(reassembly_table *table, const packet_info *pinfo,
672 const uint32_t id)
673{
674 fragment_head *fd_head;
675 reassembled_key key;
676
677 /* create key to search hash with */
678 key.frame = pinfo->num;
679 key.id = id;
680 fd_head = (fragment_head *)g_hash_table_lookup(table->reassembled_table, &key);
681
682 return fd_head;
683}
684
685/* To specify the offset for the fragment numbering, the first fragment is added with 0, and
686 * afterwards this offset is set. All additional calls to off_seq_check will calculate
687 * the number in sequence in regards to the offset */
688void
689fragment_add_seq_offset(reassembly_table *table, const packet_info *pinfo, const uint32_t id,
690 const void *data, const uint32_t fragment_offset)
691{
692 fragment_head *fd_head;
693
694 fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
695 if (!fd_head)
696 return;
697
698 /* Resetting the offset is not allowed */
699 if ( fd_head->fragment_nr_offset != 0 )
700 return;
701
702 fd_head->fragment_nr_offset = fragment_offset;
703}
704
705static void
706update_first_gap(fragment_head *fd_head, fragment_item *inserted, bool_Bool multi_insert)
707{
708 uint32_t frag_end = inserted->offset + inserted->len;
709 fragment_item *iter;
710 uint32_t contiguous;
711
712 if (inserted->offset > fd_head->contiguous_len) {
713 /* first inserted node is after first gap */
714 return;
715 } else if (fd_head->first_gap == NULL((void*)0)) {
716 /* we haven't seen first fragment yet */
717 if (inserted->offset != 0) {
718 /* inserted node is not first fragment */
719 return;
720 }
721 contiguous = inserted->len;
722 iter = inserted;
723 } else {
724 contiguous = MAX(fd_head->contiguous_len, frag_end)(((fd_head->contiguous_len) > (frag_end)) ? (fd_head->
contiguous_len) : (frag_end))
;
725 iter = multi_insert ? inserted : fd_head->first_gap;
726 }
727
728 while (iter->next) {
729 if (iter->next->offset > contiguous) {
730 break;
731 }
732 iter = iter->next;
733 contiguous = MAX(contiguous, iter->offset + iter->len)(((contiguous) > (iter->offset + iter->len)) ? (contiguous
) : (iter->offset + iter->len))
;
734 }
735
736 /* iter is either pointing to last fragment before gap or tail */
737 fd_head->first_gap = iter;
738 fd_head->contiguous_len = contiguous;
739}
740
741/*
742 * Keeping first gap and contiguous length in sync significantly speeds up
743 * LINK_FRAG() when fragments in capture file are mostly ordered. However, when
744 * fragments are removed from the list, the first gap can point to fragments
745 * that were either moved to another list or freed. Therefore when any fragment
746 * before first gap is removed, the first gap (and contiguous length) must be
747 * invalidated.
748 */
749static void fragment_reset_first_gap(fragment_head *fd_head)
750{
751 fd_head->first_gap = NULL((void*)0);
752 fd_head->contiguous_len = 0;
753 if (fd_head->next) {
754 bool_Bool multi_insert = (fd_head->next->next != NULL((void*)0));
755 update_first_gap(fd_head, fd_head->next, multi_insert);
756 }
757}
758
759/*
760 * Determines whether list modification requires first gap reset. On entry
761 * modified is NULL if all elements were removed, otherwise it points to
762 * element (reachable from fd_head) whose next pointer was changed.
763 */
764static void fragment_items_removed(fragment_head *fd_head, fragment_item *modified)
765{
766 if ((fd_head->first_gap == modified) ||
767 ((modified != NULL((void*)0)) && (modified->offset > fd_head->contiguous_len))) {
768 /* Removed elements were after first gap */
769 return;
770 }
771 fragment_reset_first_gap(fd_head);
772}
773
774/*
775 * For use with fragment_add (and not the fragment_add_seq functions).
776 * When the reassembled result is wrong (perhaps it needs to be extended), this
777 * function clears any previous reassembly result, allowing the new reassembled
778 * length to be set again.
779 */
780static void
781fragment_reset_defragmentation(fragment_head *fd_head)
782{
783 /* Caller must ensure that this function is only called when
784 * defragmentation is safe to undo. */
785 DISSECTOR_ASSERT(fd_head->flags & FD_DEFRAGMENTED)((void) ((fd_head->flags & 0x0001) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 785, "fd_head->flags & 0x0001"
))))
;
786
787 fd_head->flags &= ~(FD_DEFRAGMENTED0x0001|FD_PARTIAL_REASSEMBLY0x0040|FD_DATALEN_SET0x0400);
788 /* We have to clear TOOLONGFRAGMENT and MULTIPLETAILS because they
789 * might change when extending the reassembly. If those flags weren't
790 * set on the head, they're not set on any item. */
791 if (fd_head->flags & (FD_TOOLONGFRAGMENT0x0010|FD_MULTIPLETAILS0x0008)) {
792 for (fragment_item *fd_i = fd_head->next; fd_i; fd_i = fd_i->next) {
793 fd_i->flags &= (~FD_TOOLONGFRAGMENT0x0010) & (~FD_MULTIPLETAILS0x0008);
794 }
795 fd_head->flags &= ~(FD_TOOLONGFRAGMENT0x0010|FD_MULTIPLETAILS0x0008);
796 }
797 fd_head->datalen = 0;
798 fd_head->reassembled_in = 0;
799 fd_head->reas_in_layer_num = 0;
800}
801
802/* This function can be used to explicitly set the total length (if known)
803 * for reassembly of a PDU.
804 * This is useful for reassembly of PDUs where one may have the total length specified
805 * in the first fragment instead of as for, say, IPv4 where a flag indicates which
806 * is the last fragment.
807 *
808 * Such protocols might fragment_add with a more_frags==true for every fragment
809 * and just tell the reassembly engine the expected total length of the reassembled data
810 * using fragment_set_tot_len immediately after doing fragment_add for the first packet.
811 *
812 * Note that for FD_BLOCKSEQUENCE tot_len is the index for the tail fragment.
813 * i.e. since the block numbers start at 0, if we specify tot_len==2, that
814 * actually means we want to defragment 3 blocks, block 0, 1 and 2.
815 */
816void
817fragment_set_tot_len(reassembly_table *table, const packet_info *pinfo,
818 const uint32_t id, const void *data, const uint32_t tot_len)
819{
820 fragment_head *fd_head;
821 fragment_item *fd;
822 uint32_t max_offset = 0;
823
824 fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
825 if (!fd_head)
826 return;
827
828 /* If we're setting a block sequence number, verify that it
829 * doesn't conflict with values set by existing fragments.
830 * XXX - eliminate this check?
831 */
832 if (fd_head->flags & FD_BLOCKSEQUENCE0x0100) {
833 for (fd = fd_head->next; fd; fd = fd->next) {
834 if (fd->offset > max_offset) {
835 max_offset = fd->offset;
836 if (max_offset > tot_len) {
837 fd_head->error = "Bad total reassembly block count";
838 THROW_MESSAGE(ReassemblyError, fd_head->error)except_throw(1, (9), (fd_head->error));
839 }
840 }
841 }
842 }
843
844 if (fd_head->flags & FD_DEFRAGMENTED0x0001) {
845 if (max_offset != tot_len) {
846 fd_head->error = "Defragmented complete but total length not satisfied";
847 THROW_MESSAGE(ReassemblyError, fd_head->error)except_throw(1, (9), (fd_head->error));
848 }
849 }
850
851 /* We got this far so the value is sane. */
852 fd_head->datalen = tot_len;
853 fd_head->flags |= FD_DATALEN_SET0x0400;
854}
855
856void
857fragment_reset_tot_len(reassembly_table *table, const packet_info *pinfo,
858 const uint32_t id, const void *data, const uint32_t tot_len)
859{
860 fragment_head *fd_head;
861
862 fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
863 if (!fd_head)
864 return;
865
866 /*
867 * If FD_PARTIAL_REASSEMBLY is set, it would make the next fragment_add
868 * call set the reassembled length based on the fragment offset and
869 * length. As the length is known now, be sure to disable that magic.
870 */
871 fd_head->flags &= ~FD_PARTIAL_REASSEMBLY0x0040;
872
873 /* If the length is already as expected, there is nothing else to do. */
874 if (tot_len == fd_head->datalen)
875 return;
876
877 if (fd_head->flags & FD_DEFRAGMENTED0x0001) {
878 /*
879 * Fragments were reassembled before, clear it to allow
880 * increasing the reassembled length.
881 */
882 fragment_reset_defragmentation(fd_head);
883 }
884
885 fd_head->datalen = tot_len;
886 fd_head->flags |= FD_DATALEN_SET0x0400;
887}
888
889void
890fragment_truncate(reassembly_table *table, const packet_info *pinfo,
891 const uint32_t id, const void *data, const uint32_t tot_len)
892
893{
894 tvbuff_t *old_tvb_data;
895 fragment_head *fd_head;
896
897 fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
898 if (!fd_head)
899 return;
900
901 /* Caller must ensure that this function is only called when
902 * we are defragmented. */
903 DISSECTOR_ASSERT(fd_head->flags & FD_DEFRAGMENTED)((void) ((fd_head->flags & 0x0001) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 903, "fd_head->flags & 0x0001"
))))
;
904
905 /*
906 * If FD_PARTIAL_REASSEMBLY is set, it would make the next fragment_add
907 * call set the reassembled length based on the fragment offset and
908 * length. As the length is known now, be sure to disable that magic.
909 */
910 fd_head->flags &= ~FD_PARTIAL_REASSEMBLY0x0040;
911
912 /* If the length is already as expected, there is nothing else to do. */
913 if (tot_len == fd_head->datalen)
914 return;
915
916 DISSECTOR_ASSERT(fd_head->datalen > tot_len)((void) ((fd_head->datalen > tot_len) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 916, "fd_head->datalen > tot_len"
))))
;
917
918 old_tvb_data=fd_head->tvb_data;
919 fd_head->tvb_data = tvb_clone_offset_len(old_tvb_data, 0, tot_len);
920 tvb_set_free_cb(fd_head->tvb_data, g_free);
921
922 if (old_tvb_data)
923 tvb_add_to_chain(fd_head->tvb_data, old_tvb_data);
924 fd_head->datalen = tot_len;
925
926 /* Keep the fragments before the split point, dividing any if
927 * necessary.
928 * XXX: In rare cases, there might be fragments marked as overlap that
929 * have data both before and after the split point, and which only
930 * overlap after the split point. In that case, after dividing the
931 * fragments the first part no longer overlap.
932 * However, at this point we can't test for overlap conflicts,
933 * so we'll just leave the overlap flags as-is.
934 */
935 fd_head->flags &= ~(FD_OVERLAP0x0002|FD_OVERLAPCONFLICT0x0004|FD_TOOLONGFRAGMENT0x0010|FD_MULTIPLETAILS0x0008);
936 fragment_item *fd_i, *prev_fd = NULL((void*)0);
937 for (fd_i = fd_head->next; fd_i && (fd_i->offset < tot_len); fd_i = fd_i->next) {
938 fd_i->flags &= ~(FD_TOOLONGFRAGMENT0x0010|FD_MULTIPLETAILS0x0008);
939 /* Check for the split point occurring in the middle of the
940 * fragment. */
941 if (fd_i->offset + fd_i->len > tot_len) {
942 fd_i->len = tot_len - fd_i->offset;
943 }
944 fd_head->flags |= fd_i->flags & (FD_OVERLAP0x0002|FD_OVERLAPCONFLICT0x0004);
945 prev_fd = fd_i;
946
947 /* Below should do nothing since this is already defragmented */
948 fragment_item_free_tvb(fd_i);
949 }
950
951 /* Remove all the other fragments, as they are past the split point. */
952 if (prev_fd) {
953 prev_fd->next = NULL((void*)0);
954 } else {
955 fd_head->next = NULL((void*)0);
956 }
957 fd_head->contiguous_len = MIN(fd_head->contiguous_len, tot_len)(((fd_head->contiguous_len) < (tot_len)) ? (fd_head->
contiguous_len) : (tot_len))
;
958 fragment_items_removed(fd_head, prev_fd);
959 while (fd_i != NULL((void*)0)) {
960 fd_i = fragment_item_free(fd_i);
961 }
962}
963
964uint32_t
965fragment_get_tot_len(reassembly_table *table, const packet_info *pinfo,
966 const uint32_t id, const void *data)
967{
968 fragment_head *fd_head;
969
970 fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
971
972 if(fd_head){
973 return fd_head->datalen;
974 }
975
976 return 0;
977}
978
979/* This function will set the partial reassembly flag for a fh.
980 When this function is called, the fh MUST already exist, i.e.
981 the fh MUST be created by the initial call to fragment_add() before
982 this function is called.
983 Also note that this function MUST be called to indicate a fh will be
984 extended (increase the already stored data)
985*/
986
987void
988fragment_set_partial_reassembly(reassembly_table *table,
989 const packet_info *pinfo, const uint32_t id,
990 const void *data)
991{
992 fragment_head *fd_head;
993
994 fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
995
996 /*
997 * XXX - why not do all the stuff done early in "fragment_add_work()",
998 * turning off FD_DEFRAGMENTED and pointing the fragments' data
999 * pointers to the appropriate part of the already-reassembled
1000 * data, and clearing the data length and "reassembled in" frame
1001 * number, here? We currently have a hack in the TCP dissector
1002 * not to set the "reassembled in" value if the "partial reassembly"
1003 * flag is set, so that in the first pass through the packets
1004 * we don't falsely set a packet as reassembled in that packet
1005 * if the dissector decided that even more reassembly was needed.
1006 */
1007 if(fd_head){
1008 fd_head->flags |= FD_PARTIAL_REASSEMBLY0x0040;
1009 }
1010}
1011
1012/*
1013 * This function gets rid of an entry from a fragment table, given
1014 * a pointer to the key for that entry.
1015 *
1016 * The key freeing routine will be called by g_hash_table_remove().
1017 */
1018static void
1019fragment_unhash(reassembly_table *table, void *key)
1020{
1021 /*
1022 * Remove the entry from the fragment table.
1023 */
1024 g_hash_table_remove(table->fragment_table, key);
1025}
1026
1027/*
1028 * This function adds fragment_head structure to a reassembled-packet
1029 * hash table, using the frame numbers of each of the frames from
1030 * which it was reassembled as keys, and sets the "reassembled_in"
1031 * frame number.
1032 */
1033static void
1034fragment_reassembled(reassembly_table *table, fragment_head *fd_head,
1035 const packet_info *pinfo, const uint32_t id)
1036{
1037 reassembled_key *new_key;
1038 fragment_item *fd;
1039
1040 fd_head->ref_count = 0;
1041 if (fd_head->next == NULL((void*)0)) {
1042 /*
1043 * This was not fragmented, so there's no fragment
1044 * table; just hash it using the current frame number.
1045 */
1046 new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc ((sizeof (reassembled_key) >
0 ? sizeof (reassembled_key) : 1)))
;
1047 new_key->frame = pinfo->num;
1048 new_key->id = id;
1049 reassembled_table_insert(table->reassembled_table, new_key, fd_head);
1050 } else {
1051 /*
1052 * Hash it with the frame numbers for all the frames.
1053 */
1054 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next){
1055 new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc ((sizeof (reassembled_key) >
0 ? sizeof (reassembled_key) : 1)))
;
1056 new_key->frame = fd->frame;
1057 new_key->id = id;
1058 reassembled_table_insert(table->reassembled_table, new_key, fd_head);
1059 }
1060 }
1061 fd_head->flags |= FD_DEFRAGMENTED0x0001;
1062 fd_head->reassembled_in = pinfo->num;
1063 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
1064}
1065
1066/*
1067 * This function is a variant of the above for the single sequence
1068 * case, using id+offset (i.e., the original sequence number) for the id
1069 * in the key.
1070 */
1071static void
1072fragment_reassembled_single(reassembly_table *table, fragment_head *fd_head,
1073 const packet_info *pinfo, const uint32_t id)
1074{
1075 reassembled_key *new_key;
1076 fragment_item *fd;
1077
1078 fd_head->ref_count = 0;
1079 if (fd_head->next == NULL((void*)0)) {
1080 /*
1081 * This was not fragmented, so there's no fragment
1082 * table; just hash it using the current frame number.
1083 */
1084 new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc ((sizeof (reassembled_key) >
0 ? sizeof (reassembled_key) : 1)))
;
1085 new_key->frame = pinfo->num;
1086 new_key->id = id;
1087 reassembled_table_insert(table->reassembled_table, new_key, fd_head);
1088 } else {
1089 /*
1090 * Hash it with the frame numbers for all the frames.
1091 */
1092 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next){
1093 new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc ((sizeof (reassembled_key) >
0 ? sizeof (reassembled_key) : 1)))
;
1094 new_key->frame = fd->frame;
1095 new_key->id = id + fd->offset;
1096 reassembled_table_insert(table->reassembled_table, new_key, fd_head);
1097 }
1098 }
1099 fd_head->flags |= FD_DEFRAGMENTED0x0001;
1100 fd_head->reassembled_in = pinfo->num;
1101 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
1102}
1103
1104static void
1105LINK_FRAG(fragment_head *fd_head,fragment_item *fd)
1106{
1107 fragment_item *fd_i;
1108
1109 /* add fragment to list, keep list sorted */
1110 /* It is important that new fragments are added *after* any
1111 * fragments with the same offset (as currently done.) */
1112 if (fd_head->next == NULL((void*)0) || fd->offset < fd_head->next->offset) {
1113 /* New first fragment */
1114 fd->next = fd_head->next;
1115 fd_head->next = fd;
1116 } else {
1117 fd_i = fd_head->next;
1118 if (fd_head->first_gap != NULL((void*)0)) {
1119 if (fd->offset >= fd_head->first_gap->offset) {
1120 /* fragment is after first gap */
1121 fd_i = fd_head->first_gap;
1122 }
1123 }
1124 for(; fd_i->next; fd_i=fd_i->next) {
1125 if (fd->offset < fd_i->next->offset )
1126 break;
1127 }
1128 fd->next = fd_i->next;
1129 fd_i->next = fd;
1130 }
1131
1132 update_first_gap(fd_head, fd, false0);
1133}
1134
1135static void
1136MERGE_FRAG(fragment_head *fd_head, fragment_item *fd)
1137{
1138 fragment_item *fd_i, *tmp, *inserted = fd;
1139 bool_Bool multi_insert;
1140
1141 if (fd == NULL((void*)0)) return;
1142
1143 multi_insert = (fd->next != NULL((void*)0));
1144
1145 if (fd_head->next == NULL((void*)0)) {
1146 fd_head->next = fd;
1147 update_first_gap(fd_head, fd, multi_insert);
1148 return;
1149 }
1150
1151 if ((fd_head->first_gap != NULL((void*)0)) &&
1152 (fd->offset >= fd_head->first_gap->offset)) {
1153 /* all new fragments go after first gap */
1154 fd_i = fd_head->first_gap;
1155 } else {
1156 /* at least one new fragment goes before first gap */
1157 if (fd->offset < fd_head->next->offset) {
1158 /* inserted fragment is new head, "swap" the lists */
1159 tmp = fd_head->next;
1160 fd_head->next = fd;
1161 fd = tmp;
1162 }
1163 fd_i = fd_head->next;
1164 }
1165
1166 /* Traverse the list linked to fragment head ("main" list), checking if
1167 * fd pointer ("merge" list) should go before or after fd_i->next. Swap
1168 * fd_i->next ("main") and fd pointers ("merge") if "merge" list should
1169 * go before iterated element (fd_i). After the swap what formerly was
1170 * "merge" list essentially becomes part of "main" list (just detached
1171 * element, i.e. fd, is now head of new "merge list").
1172 */
1173 for(; fd_i->next; fd_i=fd_i->next) {
1174 if (fd->offset < fd_i->next->offset) {
1175 tmp = fd_i->next;
1176 fd_i->next = fd;
1177 fd = tmp;
1178 }
1179 }
1180 /* Reached "main" list end, attach remaining elements */
1181 fd_i->next = fd;
1182
1183 update_first_gap(fd_head, inserted, multi_insert);
1184}
1185
1186/*
1187 * This function adds a new fragment to the fragment hash table.
1188 * If this is the first fragment seen for this datagram, a new entry
1189 * is created in the hash table, otherwise this fragment is just added
1190 * to the linked list of fragments for this packet.
1191 * The list of fragments for a specific datagram is kept sorted for
1192 * easier handling.
1193 *
1194 * Returns a pointer to the head of the fragment data list if we have all the
1195 * fragments, NULL otherwise.
1196 *
1197 * This function assumes frag_offset being a byte offset into the defragment
1198 * packet.
1199 *
1200 * 01-2002
1201 * Once the fh is defragmented (= FD_DEFRAGMENTED set), it can be
1202 * extended using the FD_PARTIAL_REASSEMBLY flag. This flag should be set
1203 * using fragment_set_partial_reassembly() before calling fragment_add
1204 * with the new fragment. FD_TOOLONGFRAGMENT and FD_MULTIPLETAILS flags
1205 * are lowered when a new extension process is started.
1206 */
1207static bool_Bool
1208fragment_add_work(fragment_head *fd_head, tvbuff_t *tvb, const int offset,
1209 const packet_info *pinfo, const uint32_t frag_offset,
1210 const uint32_t frag_data_len, const bool_Bool more_frags,
1211 const uint32_t frag_frame, const bool_Bool allow_overlaps)
1212{
1213 fragment_item *fd;
1214 fragment_item *fd_i;
1215 uint32_t dfpos, fraglen, overlap;
1216 tvbuff_t *old_tvb_data;
1217 uint8_t *data;
1218
1219 /* create new fd describing this fragment */
1220 fd = new_fragment_item(frag_frame, frag_offset, frag_data_len);
1221
1222 /*
1223 * Are we adding to an already-completed reassembly?
1224 */
1225 if (fd_head->flags & FD_DEFRAGMENTED0x0001) {
1226 /*
1227 * Yes. Does this fragment go past the end of the results
1228 * of that reassembly?
1229 */
1230 if (frag_offset + frag_data_len > fd_head->datalen) {
1231 /*
1232 * Yes. Have we been requested to continue reassembly?
1233 */
1234 if (fd_head->flags & FD_PARTIAL_REASSEMBLY0x0040) {
1235 /*
1236 * Yes. Set flag in already empty fds &
1237 * point old fds to malloc'ed data.
1238 */
1239 fragment_reset_defragmentation(fd_head);
1240 } else if (!allow_overlaps) {
1241 /*
1242 * No. Bail out since we have no idea what to
1243 * do with this fragment (and if we keep going
1244 * we'll run past the end of a buffer sooner
1245 * or later).
1246 */
1247 g_slice_free(fragment_item, fd)do { if (1) g_slice_free1 (sizeof (fragment_item), (fd)); else
(void) ((fragment_item*) 0 == (fd)); } while (0)
;
1248
1249 /*
1250 * This is an attempt to add a fragment to a
1251 * reassembly that had already completed.
1252 * If it had no error, we don't want to
1253 * mark it with an error, and if it had an
1254 * error, we don't want to overwrite it, so
1255 * we don't set fd_head->error.
1256 */
1257 if (frag_offset >= fd_head->datalen) {
1258 /*
1259 * The fragment starts past the end
1260 * of the reassembled data.
1261 */
1262 THROW_MESSAGE(ReassemblyError, "New fragment past old data limits")except_throw(1, (9), ("New fragment past old data limits"));
1263 } else {
1264 /*
1265 * The fragment starts before the end
1266 * of the reassembled data, but
1267 * runs past the end. That could
1268 * just be a retransmission with extra
1269 * data, but the calling dissector
1270 * didn't set FD_PARTIAL_REASSEMBLY
1271 * so it won't be handled correctly.
1272 *
1273 * XXX: We could set FD_TOOLONGFRAGMENT
1274 * below instead.
1275 */
1276 THROW_MESSAGE(ReassemblyError, "New fragment overlaps old data (retransmission?)")except_throw(1, (9), ("New fragment overlaps old data (retransmission?)"
))
;
1277 }
1278 }
1279 } else {
1280 /*
1281 * No. That means it overlaps the completed reassembly.
1282 * This is probably a retransmission and normal
1283 * behavior. (If not, it's because the dissector
1284 * doesn't handle reused sequence numbers correctly,
1285 * e.g. #10503). Handle below.
1286 */
1287 }
1288 }
1289
1290 /* Do this after we may have bailed out (above) so that we don't leave
1291 * fd_head->frame in a bad state if we do */
1292 if (fd->frame > fd_head->frame)
1293 fd_head->frame = fd->frame;
1294
1295 if (!more_frags) {
1296 /*
1297 * This is the tail fragment in the sequence.
1298 */
1299 if (fd_head->flags & FD_DATALEN_SET0x0400) {
1300 /* ok we have already seen other tails for this packet
1301 * it might be a duplicate.
1302 */
1303 if (fd_head->datalen != (fd->offset + fd->len) ){
1304 /* Oops, this tail indicates a different packet
1305 * len than the previous ones. Something's wrong.
1306 */
1307 fd->flags |= FD_MULTIPLETAILS0x0008;
1308 fd_head->flags |= FD_MULTIPLETAILS0x0008;
1309 }
1310 } else {
1311 /* This was the first tail fragment; now we know
1312 * what the length of the packet should be.
1313 */
1314 fd_head->datalen = fd->offset + fd->len;
1315 fd_head->flags |= FD_DATALEN_SET0x0400;
1316 }
1317 }
1318
1319
1320
1321 /* If the packet is already defragmented, this MUST be an overlap.
1322 * The entire defragmented packet is in fd_head->data.
1323 * Even if we have previously defragmented this packet, we still
1324 * check it. Someone might play overlap and TTL games.
1325 */
1326 if (fd_head->flags & FD_DEFRAGMENTED0x0001) {
1327 uint32_t end_offset = fd->offset + fd->len;
1328 fd->flags |= FD_OVERLAP0x0002|FD_DEFRAGMENTED0x0001;
1329 fd_head->flags |= FD_OVERLAP0x0002;
1330 /* make sure it's not too long */
1331 /* XXX: We probably don't call this, unlike the _seq()
1332 * functions, because we throw an exception above.
1333 */
1334 if (end_offset > fd_head->datalen || end_offset < fd->offset || end_offset < fd->len) {
1335 fd->flags |= FD_TOOLONGFRAGMENT0x0010;
1336 fd_head->flags |= FD_TOOLONGFRAGMENT0x0010;
1337 }
1338 /* make sure it doesn't conflict with previous data */
1339 else if ( tvb_memeql(fd_head->tvb_data, fd->offset,
1340 tvb_get_ptr(tvb,offset,fd->len),fd->len) ){
1341 fd->flags |= FD_OVERLAPCONFLICT0x0004;
1342 fd_head->flags |= FD_OVERLAPCONFLICT0x0004;
1343 }
1344 /* it was just an overlap, link it and return */
1345 LINK_FRAG(fd_head,fd);
1346 return true1;
1347 }
1348
1349
1350
1351 /* If we have reached this point, the packet is not defragmented yet.
1352 * Save all payload in a buffer until we can defragment.
1353 */
1354 if (!tvb_bytes_exist(tvb, offset, fd->len)) {
1355 g_slice_free(fragment_item, fd)do { if (1) g_slice_free1 (sizeof (fragment_item), (fd)); else
(void) ((fragment_item*) 0 == (fd)); } while (0)
;
1356 THROW(BoundsError)except_throw(1, (1), ((void*)0));
1357 }
1358 fd->tvb_data = tvb_clone_offset_len(tvb, offset, fd->len);
1359 LINK_FRAG(fd_head,fd);
1360
1361
1362 if( !(fd_head->flags & FD_DATALEN_SET0x0400) ){
1363 /* if we don't know the datalen, there are still missing
1364 * packets. Cheaper than the check below.
1365 */
1366 return false0;
1367 }
1368
1369 /* Check if we have received the entire fragment. */
1370 if (fd_head->contiguous_len < fd_head->datalen) {
1371 /*
1372 * The amount of contiguous data we have is less than the
1373 * amount of data we're trying to reassemble, so we haven't
1374 * received all packets yet.
1375 */
1376 return false0;
1377 }
1378
1379 /* we have received an entire packet, defragment it and
1380 * free all fragments
1381 */
1382 /* store old data just in case */
1383 old_tvb_data=fd_head->tvb_data;
1384 data = (uint8_t *) g_malloc(fd_head->datalen);
1385 fd_head->tvb_data = tvb_new_real_data(data, fd_head->datalen, fd_head->datalen);
1386 tvb_set_free_cb(fd_head->tvb_data, g_free);
1387
1388 dfpos = old_tvb_data ? tvb_captured_length(old_tvb_data) : 0;
1389 if (dfpos) {
1390 memcpy(data, tvb_get_ptr(old_tvb_data, 0, dfpos), MIN(fd_head->datalen, dfpos)(((fd_head->datalen) < (dfpos)) ? (fd_head->datalen)
: (dfpos))
);
1391 }
1392 /* add all data fragments that have not already been added, i.e.,
1393 * if the defragmentation was reset after partial reassembly,
1394 * but we have to check the previously added ones as well for
1395 * TOOLONGFRAGMENT as the datalen has changed. */
1396 for (fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
1397 if (fd_i->len) {
1398 /*
1399 * The contiguous length check above also
1400 * ensures that the only gaps that exist here
1401 * are ones where a fragment starts past the
1402 * end of the reassembled datagram, and there's
1403 * a gap between the previous fragment and
1404 * that fragment.
1405 *
1406 * A "DESEGMENT_UNTIL_FIN" was involved wherein the
1407 * FIN packet had an offset less than the highest
1408 * fragment offset seen. [Seen from a fuzz-test:
1409 * bug #2470]).
1410 *
1411 * Note that the "overlap" compare must only be
1412 * done for fragments with (offset+len) <= fd_head->datalen
1413 * and thus within the newly g_malloc'd buffer.
1414 */
1415
1416 if (fd_i->offset >= fd_head->datalen) {
1417 /*
1418 * Fragment starts after the end
1419 * of the reassembled packet.
1420 *
1421 * This can happen if the length was
1422 * set after the offending fragment
1423 * was added to the reassembly.
1424 *
1425 * Flag this fragment, but don't
1426 * try to extract any data from
1427 * it, as there's no place to put
1428 * it.
1429 *
1430 * XXX - add different flag value
1431 * for this.
1432 */
1433 fd_i->flags |= FD_TOOLONGFRAGMENT0x0010;
1434 fd_head->flags |= FD_TOOLONGFRAGMENT0x0010;
1435 } else if (fd_i->offset + fd_i->len < fd_i->offset) {
1436 /* Integer overflow, unhandled by rest of
1437 * code so error out. This check handles
1438 * all possible remaining overflows.
1439 */
1440 fd_head->error = "offset + len < offset";
1441 } else {
1442 fraglen = fd_i->len;
1443 if (fd_i->offset + fraglen > fd_head->datalen) {
1444 /*
1445 * Fragment goes past the end
1446 * of the packet, as indicated
1447 * by the last fragment.
1448 *
1449 * This can happen if the
1450 * length was set after the
1451 * offending fragment was
1452 * added to the reassembly.
1453 *
1454 * Mark it as such, and only
1455 * copy from it what fits in
1456 * the packet.
1457 */
1458 fd_i->flags |= FD_TOOLONGFRAGMENT0x0010;
1459 fd_head->flags |= FD_TOOLONGFRAGMENT0x0010;
1460 fraglen = fd_head->datalen - fd_i->offset;
1461 }
1462 if (fd_i->flags & FD_DEFRAGMENTED0x0001) {
1463 /* If we already added the item the
1464 * previous time, we're done. */
1465 continue;
1466 }
1467 if (!fd_i->tvb_data) {
1468 /* We check this here because
1469 * previously added items now
1470 * have no data (not an error). */
1471 fd_head->error = "no data";
1472 continue;
1473 }
1474 overlap = 0;
1475 if (fd_i->offset < dfpos) {
1476 /* The new item's begins before the
1477 * existing end. How much overlap? */
1478 overlap = dfpos - fd_i->offset;
1479 /* duplicate/retransmission/overlap */
1480 uint32_t cmp_len = MIN(fd_i->len,overlap)(((fd_i->len) < (overlap)) ? (fd_i->len) : (overlap)
)
;
1481
1482 fd_i->flags |= FD_OVERLAP0x0002;
1483 fd_head->flags |= FD_OVERLAP0x0002;
1484 if ( memcmp(data + fd_i->offset,
1485 tvb_get_ptr(fd_i->tvb_data, 0, cmp_len),
1486 cmp_len)
1487 ) {
1488 fd_i->flags |= FD_OVERLAPCONFLICT0x0004;
1489 fd_head->flags |= FD_OVERLAPCONFLICT0x0004;
1490 }
1491 }
1492 /* XXX: As in the fragment_add_seq funcs
1493 * like fragment_defragment_and_free() the
1494 * existing behavior does not overwrite
1495 * overlapping bytes even if there is a
1496 * conflict. It only adds new bytes.
1497 *
1498 * Since we only add fragments to a reassembly
1499 * if the reassembly isn't complete, the most
1500 * common case for overlap conflicts is when
1501 * an earlier reassembly isn't fully contained
1502 * in the capture, and we've reused an
1503 * identification number / wrapped around
1504 * offset sequence numbers much later in the
1505 * capture. In that case, we probably *do*
1506 * want to overwrite conflicting bytes, since
1507 * the earlier fragments didn't form a complete
1508 * reassembly and should be effectively thrown
1509 * out rather than mixed with the new ones?
1510 */
1511 if (fd_i->offset + fraglen > dfpos) {
1512 memcpy(data+dfpos,
1513 tvb_get_ptr(fd_i->tvb_data, overlap, fraglen-overlap),
1514 fraglen-overlap);
1515 dfpos = fd_i->offset + fraglen;
1516 }
1517 }
1518 /* Mark that this fragment as used and clear data. */
1519 fd_i->flags |= FD_DEFRAGMENTED0x0001;
1520 fragment_item_free_tvb(fd_i);
1521 }
1522 }
1523
1524 if (old_tvb_data)
1525 tvb_add_to_chain(tvb, old_tvb_data);
1526 /* mark this packet as defragmented.
1527 allows us to skip any trailing fragments */
1528 fd_head->flags |= FD_DEFRAGMENTED0x0001;
1529 fd_head->reassembled_in=pinfo->num;
1530 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
1531
1532 /* we don't throw until here to avoid leaking old_data and others */
1533 if (fd_head->error) {
1534 THROW_MESSAGE(ReassemblyError, fd_head->error)except_throw(1, (9), (fd_head->error));
1535 }
1536
1537 return true1;
1538}
1539
1540static fragment_head *
1541fragment_add_common(reassembly_table *table, tvbuff_t *tvb, const int offset,
1542 const packet_info *pinfo, const uint32_t id,
1543 const void *data, const uint32_t frag_offset,
1544 const uint32_t frag_data_len, const bool_Bool more_frags,
1545 const bool_Bool check_already_added,
1546 const uint32_t frag_frame)
1547{
1548 fragment_head *fd_head;
1549 fragment_item *fd_item;
1550 bool_Bool already_added;
1551
1552
1553 /*
1554 * Dissector shouldn't give us garbage tvb info.
1555 *
1556 * XXX - should this code take responsibility for preventing
1557 * reassembly if data is missing due to the packets being
1558 * sliced, rather than leaving it up to dissectors?
1559 */
1560 DISSECTOR_ASSERT(tvb_bytes_exist(tvb, offset, frag_data_len))((void) ((tvb_bytes_exist(tvb, offset, frag_data_len)) ? (void
)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/reassemble.c", 1560, "tvb_bytes_exist(tvb, offset, frag_data_len)"
))))
;
1561
1562 fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
1563
1564#if 0
1565 /* debug output of associated fragments. */
1566 /* leave it here for future debugging sessions */
1567 if(strcmp(pinfo->current_proto, "DCERPC") == 0) {
1568 printf("proto:%s num:%u id:%u offset:%u len:%u more:%u visited:%u\n",
1569 pinfo->current_proto, pinfo->num, id, frag_offset, frag_data_len, more_frags, pinfo->fd->visited);
1570 if(fd_head != NULL((void*)0)) {
1571 for(fd_item=fd_head->next;fd_item;fd_item=fd_item->next){
1572 printf("fd_frame:%u fd_offset:%u len:%u datalen:%u\n",
1573 fd_item->frame, fd_item->offset, fd_item->len, fd_item->datalen);
1574 }
1575 }
1576 }
1577#endif
1578
1579 /*
1580 * Is this the first pass through the capture?
1581 */
1582 if (!pinfo->fd->visited) {
1583 /*
1584 * Yes, so we could be doing reassembly. If
1585 * "check_already_added" is true, and fd_head is non-null,
1586 * meaning that this fragment would be added to an
1587 * in-progress reassembly, check if we have seen this
1588 * fragment before, i.e., if we have already added it to
1589 * that reassembly. That can be true even on the first pass
1590 * since we sometimes might call a subdissector multiple
1591 * times.
1592 *
1593 * We check both the frame number and the fragment offset,
1594 * so that we support multiple fragments from the same
1595 * frame being added to the same reassembled PDU.
1596 */
1597 if (check_already_added && fd_head != NULL((void*)0)) {
1598 /*
1599 * fd_head->frame is the maximum of the frame
1600 * numbers of all the fragments added to this
1601 * reassembly; if this frame is later than that
1602 * frame, we know it hasn't been added yet.
1603 */
1604 if (frag_frame <= fd_head->frame) {
1605 already_added = false0;
1606 /*
1607 * The first item in the reassembly list
1608 * is not a fragment, it's a data structure
1609 * for the reassembled packet, so we
1610 * start checking with the next item.
1611 */
1612 for (fd_item = fd_head->next; fd_item;
1613 fd_item = fd_item->next) {
1614 if (frag_frame == fd_item->frame &&
1615 frag_offset == fd_item->offset) {
1616 already_added = true1;
1617 break;
1618 }
1619 }
1620 if (already_added) {
1621 /*
1622 * Have we already finished
1623 * reassembling?
1624 */
1625 if (fd_head->flags & FD_DEFRAGMENTED0x0001) {
1626 /*
1627 * Yes.
1628 * XXX - can this ever happen?
1629 */
1630 THROW_MESSAGE(ReassemblyError,except_throw(1, (9), ("Frame already added in first pass"))
1631 "Frame already added in first pass")except_throw(1, (9), ("Frame already added in first pass"));
1632 } else {
1633 /*
1634 * No.
1635 */
1636 return NULL((void*)0);
1637 }
1638 }
1639 }
1640 }
1641 } else {
1642 /*
1643 * No, so we've already done all the reassembly and added
1644 * all the fragments. Do we have a reassembly and, if so,
1645 * have we finished reassembling?
1646 */
1647 if (fd_head != NULL((void*)0) && fd_head->flags & FD_DEFRAGMENTED0x0001) {
1648 /*
1649 * Yes. This is probably being done after the
1650 * first pass, and we've already done the work
1651 * on the first pass.
1652 *
1653 * If the reassembly got a fatal error, throw that
1654 * error again.
1655 */
1656 if (fd_head->error)
1657 THROW_MESSAGE(ReassemblyError, fd_head->error)except_throw(1, (9), (fd_head->error));
1658
1659 /*
1660 * Is it later in the capture than all of the
1661 * fragments in the reassembly?
1662 */
1663 if (frag_frame > fd_head->frame) {
1664 /*
1665 * Yes, so report this as a problem,
1666 * possibly a retransmission.
1667 */
1668 THROW_MESSAGE(ReassemblyError, "New fragment overlaps old data (retransmission?)")except_throw(1, (9), ("New fragment overlaps old data (retransmission?)"
))
;
1669 }
1670
1671 /*
1672 * Does this fragment go past the end of the
1673 * results of that reassembly?
1674 */
1675 if (frag_offset + frag_data_len > fd_head->datalen) {
1676 /*
1677 * Yes.
1678 */
1679 if (frag_offset >= fd_head->datalen) {
1680 /*
1681 * The fragment starts past the
1682 * end of the reassembled data.
1683 */
1684 THROW_MESSAGE(ReassemblyError, "New fragment past old data limits")except_throw(1, (9), ("New fragment past old data limits"));
1685 } else {
1686 /*
1687 * The fragment starts before the end
1688 * of the reassembled data, but
1689 * runs past the end. That could
1690 * just be a retransmission.
1691 */
1692 THROW_MESSAGE(ReassemblyError, "New fragment overlaps old data (retransmission?)")except_throw(1, (9), ("New fragment overlaps old data (retransmission?)"
))
;
1693 }
1694 }
1695
1696 return fd_head;
1697 } else {
1698 /*
1699 * No.
1700 */
1701 return NULL((void*)0);
1702 }
1703 }
1704
1705 if (fd_head==NULL((void*)0)){
1706 /* not found, this must be the first snooped fragment for this
1707 * packet. Create list-head.
1708 */
1709 fd_head = new_head(0);
1710
1711 /*
1712 * Insert it into the hash table.
1713 */
1714 insert_fd_head(table, fd_head, pinfo, id, data);
1715 }
1716
1717 if (fragment_add_work(fd_head, tvb, offset, pinfo, frag_offset,
1718 frag_data_len, more_frags, frag_frame, false0)) {
1719 /*
1720 * Reassembly is complete.
1721 */
1722 return fd_head;
1723 } else {
1724 /*
1725 * Reassembly isn't complete.
1726 */
1727 return NULL((void*)0);
1728 }
1729}
1730
1731fragment_head *
1732fragment_add(reassembly_table *table, tvbuff_t *tvb, const int offset,
1733 const packet_info *pinfo, const uint32_t id, const void *data,
1734 const uint32_t frag_offset, const uint32_t frag_data_len,
1735 const bool_Bool more_frags)
1736{
1737 return fragment_add_common(table, tvb, offset, pinfo, id, data,
1738 frag_offset, frag_data_len, more_frags, true1, pinfo->num);
1739}
1740
1741/*
1742 * For use when you can have multiple fragments in the same frame added
1743 * to the same reassembled PDU, e.g. with ONC RPC-over-TCP.
1744 */
1745fragment_head *
1746fragment_add_multiple_ok(reassembly_table *table, tvbuff_t *tvb,
1747 const int offset, const packet_info *pinfo,
1748 const uint32_t id, const void *data,
1749 const uint32_t frag_offset,
1750 const uint32_t frag_data_len, const bool_Bool more_frags)
1751{
1752 return fragment_add_common(table, tvb, offset, pinfo, id, data,
1753 frag_offset, frag_data_len, more_frags, false0, pinfo->num);
1754}
1755
1756/*
1757 * For use in protocols like TCP when you are adding an out of order segment
1758 * that arrived in an earlier frame because the correct fragment id could not
1759 * be determined until later. By allowing fd->frame to be different than
1760 * pinfo->num, show_fragment_tree will display the correct fragment numbers.
1761 *
1762 * Note that pinfo is still used to set reassembled_in if we have all the
1763 * fragments, so that results on subsequent passes can be the same as the
1764 * first pass.
1765 */
1766fragment_head *
1767fragment_add_out_of_order(reassembly_table *table, tvbuff_t *tvb,
1768 const int offset, const packet_info *pinfo,
1769 const uint32_t id, const void *data,
1770 const uint32_t frag_offset,
1771 const uint32_t frag_data_len,
1772 const bool_Bool more_frags, const uint32_t frag_frame)
1773{
1774 return fragment_add_common(table, tvb, offset, pinfo, id, data,
1775 frag_offset, frag_data_len, more_frags, true1, frag_frame);
1776}
1777
1778
1779static fragment_head *
1780fragment_add_check_common(reassembly_table *table, tvbuff_t *tvb, const int offset,
1781 const packet_info *pinfo, const uint32_t id,
1782 const void *data, uint32_t frag_offset,
1783 const uint32_t frag_data_len, const bool_Bool more_frags,
1784 const uint32_t flags, const uint32_t fallback_frame)
1785{
1786 reassembled_key reass_key;
1787 fragment_head *fd_head;
1788 void *orig_key;
1789 bool_Bool late_retransmission = false0;
1790
1791 /*
1792 * If this isn't the first pass, look for this frame in the table
1793 * of reassembled packets.
1794 */
1795 if (pinfo->fd->visited) {
1796 reass_key.frame = pinfo->num;
1797 reass_key.id = id;
1798 return (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
1799 }
1800
1801 /* Looks up a key in the GHashTable, returning the original key and the associated value
1802 * and a bool which is true if the key was found. This is useful if you need to free
1803 * the memory allocated for the original key, for example before calling g_hash_table_remove()
1804 */
1805 fd_head = lookup_fd_head(table, pinfo, id, data, &orig_key);
1806 if ((fd_head == NULL((void*)0)) && (fallback_frame != pinfo->num)) {
1807 /* Check if there is completed reassembly reachable from fallback frame */
1808 reass_key.frame = fallback_frame;
1809 reass_key.id = id;
1810 fd_head = (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
1811 if (fd_head != NULL((void*)0)) {
1812 /* Found completely reassembled packet, hash it with current frame number */
1813 reassembled_key *new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc ((sizeof (reassembled_key) >
0 ? sizeof (reassembled_key) : 1)))
;
1814 new_key->frame = pinfo->num;
1815 new_key->id = id;
1816 reassembled_table_insert(table->reassembled_table, new_key, fd_head);
1817 late_retransmission = true1;
1818 }
1819 }
1820 if (fd_head == NULL((void*)0)) {
1821 /* not found, this must be the first snooped fragment for this
1822 * packet. Create list-head.
1823 */
1824 fd_head = new_head(0);
1825
1826 if((flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001)
1827 && !more_frags) {
1828 /*
1829 * This is the last fragment for this packet, and
1830 * is the only one we've seen.
1831 *
1832 * We assume this is the first and only fragment for
1833 * this packet; just add the head of the list to
1834 * the table of reassembled packets.
1835 */
1836 /* To save memory, we don't actually copy the
1837 * fragment from the tvbuff to the fragment, and in
1838 * process_reassembled_data just return back a subset
1839 * of the original tvbuff (which must be passed in).
1840 */
1841 fd_head->datalen = frag_data_len;
1842 fd_head->reassembled_in=pinfo->num;
1843 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
1844 /*
1845 * Add this item to the table of reassembled packets.
1846 */
1847 fragment_reassembled(table, fd_head, pinfo, id);
1848 return fd_head;
1849 }
1850 /*
1851 * Save the key, for unhashing it later.
1852 */
1853 orig_key = insert_fd_head(table, fd_head, pinfo, id, data);
1854
1855 if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001)
1856 frag_offset = 0;
1857 } else {
1858 if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001) {
1859 /* There are no gaps by construction, so we can
1860 * simply use the contiguous length. */
1861 frag_offset = fd_head->contiguous_len;
1862 }
1863 }
1864
1865 /*
1866 * If this is a short frame, then we can't, and don't, do
1867 * reassembly on it. We just give up.
1868 */
1869 if (!tvb_bytes_exist(tvb, offset, frag_data_len)) {
1870 return NULL((void*)0);
1871 }
1872
1873 if (fragment_add_work(fd_head, tvb, offset, pinfo, frag_offset,
1874 frag_data_len, more_frags, pinfo->num, late_retransmission)) {
1875 /* Nothing left to do if it was a late retransmission */
1876 if (late_retransmission) {
1877 return fd_head;
1878 }
1879 /*
1880 * Reassembly is complete.
1881 * Remove this from the table of in-progress
1882 * reassemblies, add it to the table of
1883 * reassembled packets, and return it.
1884 */
1885
1886 /*
1887 * Remove this from the table of in-progress reassemblies,
1888 * and free up any memory used for it in that table.
1889 */
1890 fragment_unhash(table, orig_key);
1891
1892 /*
1893 * Add this item to the table of reassembled packets.
1894 */
1895 fragment_reassembled(table, fd_head, pinfo, id);
1896 return fd_head;
1897 } else {
1898 /*
1899 * Reassembly isn't complete.
1900 */
1901 return NULL((void*)0);
1902 }
1903}
1904
1905fragment_head *
1906fragment_add_check_with_fallback(reassembly_table *table, tvbuff_t *tvb, const int offset,
1907 const packet_info *pinfo, const uint32_t id,
1908 const void *data, const uint32_t frag_offset,
1909 const uint32_t frag_data_len, const bool_Bool more_frags,
1910 const uint32_t fallback_frame)
1911{
1912 return fragment_add_check_common(table, tvb, offset, pinfo, id, data,
1913 frag_offset, frag_data_len, more_frags, 0, fallback_frame);
1914}
1915
1916fragment_head *
1917fragment_add_check(reassembly_table *table, tvbuff_t *tvb, const int offset,
1918 const packet_info *pinfo, const uint32_t id,
1919 const void *data, const uint32_t frag_offset,
1920 const uint32_t frag_data_len, const bool_Bool more_frags)
1921{
1922 return fragment_add_check_common(table, tvb, offset, pinfo, id, data,
1923 frag_offset, frag_data_len, more_frags, 0, pinfo->num);
1924}
1925
1926fragment_head *
1927fragment_add_check_next(reassembly_table *table, tvbuff_t *tvb, const int offset,
1928 const packet_info *pinfo, const uint32_t id,
1929 const void *data,
1930 const uint32_t frag_data_len, const bool_Bool more_frags)
1931{
1932 return fragment_add_check_common(table, tvb, offset, pinfo, id, data,
1933 0, frag_data_len, more_frags, REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001, pinfo->num);
1934}
1935
1936static void
1937fragment_defragment_and_free (fragment_head *fd_head, const packet_info *pinfo)
1938{
1939 fragment_item *fd_i = NULL((void*)0);
1940 fragment_item *last_fd = NULL((void*)0);
1941 uint32_t dfpos = 0, old_dfpos = 0, size = 0;
1942 tvbuff_t *old_tvb_data = NULL((void*)0);
1943 uint8_t *data;
1944
1945 for(fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
7
Loop condition is false. Execution continues on line 1953
1946 if(!last_fd || last_fd->offset!=fd_i->offset){
1947 size+=fd_i->len;
1948 }
1949 last_fd=fd_i;
1950 }
1951
1952 /* store old data in case the fd_i->data pointers refer to it */
1953 old_tvb_data=fd_head->tvb_data;
1954 data = (uint8_t *) g_malloc(size);
8
Memory is allocated
1955 fd_head->tvb_data = tvb_new_real_data(data, size, size);
1956 tvb_set_free_cb(fd_head->tvb_data, g_free);
1957 fd_head->len = size; /* record size for caller */
1958
1959 if (old_tvb_data) {
9
Assuming 'old_tvb_data' is null
10
Taking false branch
1960 dfpos = tvb_captured_length(old_tvb_data);
1961 memcpy(data, tvb_get_ptr(old_tvb_data, 0, dfpos), MIN(size, dfpos)(((size) < (dfpos)) ? (size) : (dfpos)));
1962 }
1963
1964 /* add all data fragments */
1965 last_fd=NULL((void*)0);
1966 dfpos = 0;
1967 for (fd_i=fd_head->next; fd_i; fd_i=fd_i->next) {
11
Loop condition is false. Execution jumps to the end of the function
1968 if (fd_i->len) {
1969 if(!last_fd || last_fd->offset != fd_i->offset) {
1970 /* First fragment or in-sequence fragment */
1971 if (!(fd_i->flags & FD_DEFRAGMENTED0x0001)) {
1972 /* Already copied on the first pass */
1973 memcpy(data+dfpos, tvb_get_ptr(fd_i->tvb_data, 0, fd_i->len), fd_i->len);
1974 }
1975 /* But we need the position for overlap calculation of new fragments */
1976 old_dfpos = dfpos;
1977 dfpos += fd_i->len;
1978 } else if (!(fd_i->flags & FD_DEFRAGMENTED0x0001)){
1979 /* duplicate/retransmission/overlap */
1980 /* Note that overlaps of old fragments were already calculated. */
1981 fd_i->flags |= FD_OVERLAP0x0002;
1982 fd_head->flags |= FD_OVERLAP0x0002;
1983 if((old_dfpos + fd_i->len != dfpos)
1984 || tvb_memeql(fd_i->tvb_data, 0, data+old_dfpos, fd_i->len) ) {
1985 fd_i->flags |= FD_OVERLAPCONFLICT0x0004;
1986 fd_head->flags |= FD_OVERLAPCONFLICT0x0004;
1987 }
1988 }
1989 fragment_item_free_tvb(fd_i);
1990 fd_i->flags |= FD_DEFRAGMENTED0x0001;
1991 }
1992 last_fd=fd_i;
1993 }
1994
1995 if (old_tvb_data)
12
Potential leak of memory pointed to by 'data'
1996 tvb_free(old_tvb_data);
1997
1998 /* mark this packet as defragmented.
1999 * allows us to skip any trailing fragments.
2000 */
2001 fd_head->flags |= FD_DEFRAGMENTED0x0001;
2002 fd_head->reassembled_in=pinfo->num;
2003 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
2004}
2005
2006/*
2007 * This function adds a new fragment to the entry for a reassembly
2008 * operation.
2009 *
2010 * The list of fragments for a specific datagram is kept sorted for
2011 * easier handling.
2012 *
2013 * Returns true if we have all the fragments, false otherwise.
2014 *
2015 * This function assumes frag_number being a block sequence number.
2016 * The bsn for the first block is 0.
2017 */
2018static bool_Bool
2019fragment_add_seq_work(fragment_head *fd_head, tvbuff_t *tvb, const int offset,
2020 const packet_info *pinfo, const uint32_t frag_number,
2021 const uint32_t frag_data_len, const bool_Bool more_frags)
2022{
2023 fragment_item *fd;
2024 fragment_item *fd_i;
2025 fragment_item *last_fd;
2026 uint32_t max, dfpos;
2027 uint32_t frag_number_work;
2028
2029 /* Enables the use of fragment sequence numbers, which do not start with 0 */
2030 frag_number_work = frag_number;
2031 if ( fd_head->fragment_nr_offset != 0 )
2032 if ( frag_number_work >= fd_head->fragment_nr_offset )
2033 frag_number_work = frag_number - fd_head->fragment_nr_offset;
2034
2035 /* if the partial reassembly flag has been set, and we are extending
2036 * the pdu, un-reassemble the pdu. This means pointing old fds to malloc'ed data.
2037 */
2038 if(fd_head->flags & FD_DEFRAGMENTED0x0001 && frag_number_work >= fd_head->datalen &&
2039 fd_head->flags & FD_PARTIAL_REASSEMBLY0x0040){
2040
2041 fragment_reset_defragmentation(fd_head);
2042 }
2043
2044
2045 /* create new fd describing this fragment */
2046 fd = new_fragment_item(pinfo->num, frag_number_work, frag_data_len);
2047
2048 /* fd_head->frame is the maximum of the frame numbers of all the
2049 * fragments added to the reassembly. */
2050 if (fd->frame > fd_head->frame)
2051 fd_head->frame = fd->frame;
2052
2053 if (!more_frags) {
2054 /*
2055 * This is the tail fragment in the sequence.
2056 */
2057 if (fd_head->flags&FD_DATALEN_SET0x0400) {
2058 /* ok we have already seen other tails for this packet
2059 * it might be a duplicate.
2060 */
2061 if (fd_head->datalen != fd->offset ){
2062 /* Oops, this tail indicates a different packet
2063 * len than the previous ones. Something's wrong.
2064 */
2065 fd->flags |= FD_MULTIPLETAILS0x0008;
2066 fd_head->flags |= FD_MULTIPLETAILS0x0008;
2067 }
2068 } else {
2069 /* this was the first tail fragment, now we know the
2070 * sequence number of that fragment (which is NOT
2071 * the length of the packet!)
2072 */
2073 fd_head->datalen = fd->offset;
2074 fd_head->flags |= FD_DATALEN_SET0x0400;
2075 }
2076 }
2077
2078 /* If the packet is already defragmented, this MUST be an overlap.
2079 * The entire defragmented packet is in fd_head->data
2080 * Even if we have previously defragmented this packet, we still check
2081 * check it. Someone might play overlap and TTL games.
2082 */
2083 if (fd_head->flags & FD_DEFRAGMENTED0x0001) {
2084 fd->flags |= FD_OVERLAP0x0002|FD_DEFRAGMENTED0x0001;
2085 fd_head->flags |= FD_OVERLAP0x0002;
2086
2087 /* make sure it's not past the end */
2088 if (fd->offset > fd_head->datalen) {
2089 /* new fragment comes after the end */
2090 fd->flags |= FD_TOOLONGFRAGMENT0x0010;
2091 fd_head->flags |= FD_TOOLONGFRAGMENT0x0010;
2092 LINK_FRAG(fd_head,fd);
2093 return true1;
2094 }
2095 /* make sure it doesn't conflict with previous data */
2096 dfpos=0;
2097 last_fd=NULL((void*)0);
2098 for (fd_i=fd_head->next;fd_i && (fd_i->offset!=fd->offset);fd_i=fd_i->next) {
2099 if (!last_fd || last_fd->offset!=fd_i->offset){
2100 dfpos += fd_i->len;
2101 }
2102 last_fd=fd_i;
2103 }
2104 if(fd_i){
2105 /* new fragment overlaps existing fragment */
2106 if(fd_i->len!=fd->len){
2107 /*
2108 * They have different lengths; this
2109 * is definitely a conflict.
2110 */
2111 fd->flags |= FD_OVERLAPCONFLICT0x0004;
2112 fd_head->flags |= FD_OVERLAPCONFLICT0x0004;
2113 LINK_FRAG(fd_head,fd);
2114 return true1;
2115 }
2116 DISSECTOR_ASSERT(fd_head->len >= dfpos + fd->len)((void) ((fd_head->len >= dfpos + fd->len) ? (void)0
: (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/reassemble.c", 2116, "fd_head->len >= dfpos + fd->len"
))))
;
2117 if (tvb_memeql(fd_head->tvb_data, dfpos,
2118 tvb_get_ptr(tvb,offset,fd->len),fd->len) ){
2119 /*
2120 * They have the same length, but the
2121 * data isn't the same.
2122 */
2123 fd->flags |= FD_OVERLAPCONFLICT0x0004;
2124 fd_head->flags |= FD_OVERLAPCONFLICT0x0004;
2125 LINK_FRAG(fd_head,fd);
2126 return true1;
2127 }
2128 /* it was just an overlap, link it and return */
2129 LINK_FRAG(fd_head,fd);
2130 return true1;
2131 } else {
2132 /*
2133 * New fragment doesn't overlap an existing
2134 * fragment - there was presumably a gap in
2135 * the sequence number space.
2136 *
2137 * XXX - what should we do here? Is it always
2138 * the case that there are no gaps, or are there
2139 * protcols using sequence numbers where there
2140 * can be gaps?
2141 *
2142 * If the former, the check below for having
2143 * received all the fragments should check for
2144 * holes in the sequence number space and for the
2145 * first sequence number being 0. If we do that,
2146 * the only way we can get here is if this fragment
2147 * is past the end of the sequence number space -
2148 * but the check for "fd->offset > fd_head->datalen"
2149 * would have caught that above, so it can't happen.
2150 *
2151 * If the latter, we don't have a good way of
2152 * knowing whether reassembly is complete if we
2153 * get packet out of order such that the "last"
2154 * fragment doesn't show up last - but, unless
2155 * in-order reliable delivery of fragments is
2156 * guaranteed, an implementation of the protocol
2157 * has no way of knowing whether reassembly is
2158 * complete, either.
2159 *
2160 * For now, we just link the fragment in and
2161 * return.
2162 */
2163 LINK_FRAG(fd_head,fd);
2164 return true1;
2165 }
2166 }
2167
2168 /* If we have reached this point, the packet is not defragmented yet.
2169 * Save all payload in a buffer until we can defragment.
2170 */
2171 /* check len, there may be a fragment with 0 len, that is actually the tail */
2172 if (fd->len) {
2173 if (!tvb_bytes_exist(tvb, offset, fd->len)) {
2174 /* abort if we didn't capture the entire fragment due
2175 * to a too-short snapshot length */
2176 g_slice_free(fragment_item, fd)do { if (1) g_slice_free1 (sizeof (fragment_item), (fd)); else
(void) ((fragment_item*) 0 == (fd)); } while (0)
;
2177 return false0;
2178 }
2179
2180 fd->tvb_data = tvb_clone_offset_len(tvb, offset, fd->len);
2181 }
2182 LINK_FRAG(fd_head,fd);
2183
2184
2185 if( !(fd_head->flags & FD_DATALEN_SET0x0400) ){
2186 /* if we don't know the sequence number of the last fragment,
2187 * there are definitely still missing packets. Cheaper than
2188 * the check below.
2189 */
2190 return false0;
2191 }
2192
2193
2194 /* check if we have received the entire fragment
2195 * this is easy since the list is sorted and the head is faked.
2196 * common case the whole list is scanned.
2197 */
2198 max = 0;
2199 for(fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
2200 if ( fd_i->offset==max ){
2201 max++;
2202 }
2203 }
2204 /* max will now be datalen+1 if all fragments have been seen */
2205
2206 if (max <= fd_head->datalen) {
2207 /* we have not received all packets yet */
2208 return false0;
2209 }
2210
2211
2212 if (max > (fd_head->datalen+1)) {
2213 /* oops, too long fragment detected */
2214 fd->flags |= FD_TOOLONGFRAGMENT0x0010;
2215 fd_head->flags |= FD_TOOLONGFRAGMENT0x0010;
2216 }
2217
2218
2219 /* we have received an entire packet, defragment it and
2220 * free all fragments
2221 */
2222 fragment_defragment_and_free(fd_head, pinfo);
2223
2224 return true1;
2225}
2226
2227/*
2228 * This function adds a new fragment to the fragment hash table.
2229 * If this is the first fragment seen for this datagram, a new entry
2230 * is created in the hash table, otherwise this fragment is just added
2231 * to the linked list of fragments for this packet.
2232 *
2233 * Returns a pointer to the head of the fragment data list if we have all the
2234 * fragments, NULL otherwise.
2235 *
2236 * This function assumes frag_number being a block sequence number.
2237 * The bsn for the first block is 0.
2238 */
2239static fragment_head *
2240fragment_add_seq_common(reassembly_table *table, tvbuff_t *tvb,
2241 const int offset, const packet_info *pinfo,
2242 const uint32_t id, const void *data,
2243 uint32_t frag_number, const uint32_t frag_data_len,
2244 const bool_Bool more_frags, const uint32_t flags,
2245 void * *orig_keyp)
2246{
2247 fragment_head *fd_head;
2248 void *orig_key;
2249
2250 fd_head = lookup_fd_head(table, pinfo, id, data, &orig_key);
2251
2252 /* have we already seen this frame ?*/
2253 if (pinfo->fd->visited) {
2254 if (fd_head != NULL((void*)0) && fd_head->flags & FD_DEFRAGMENTED0x0001) {
2255 if (orig_keyp != NULL((void*)0))
2256 *orig_keyp = orig_key;
2257 return fd_head;
2258 } else {
2259 return NULL((void*)0);
2260 }
2261 }
2262
2263 if (fd_head==NULL((void*)0)){
2264 /* not found, this must be the first snooped fragment for this
2265 * packet. Create list-head.
2266 */
2267 fd_head = new_head(FD_BLOCKSEQUENCE0x0100);
2268
2269 if((flags & (REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001|REASSEMBLE_FLAGS_802_11_HACK0x0002))
2270 && !more_frags) {
2271 /*
2272 * This is the last fragment for this packet, and
2273 * is the only one we've seen.
2274 *
2275 * Either we don't have sequence numbers, in which
2276 * case we assume this is the first fragment for
2277 * this packet, or we're doing special 802.11
2278 * processing, in which case we assume it's one
2279 * of those reassembled packets with a non-zero
2280 * fragment number (see packet-80211.c); just
2281 * return a pointer to the head of the list;
2282 * fragment_add_seq_check will then add it to the table
2283 * of reassembled packets.
2284 */
2285 if (orig_keyp != NULL((void*)0))
2286 *orig_keyp = NULL((void*)0);
2287 /* To save memory, we don't actually copy the
2288 * fragment from the tvbuff to the fragment, and in
2289 * process_reassembled_data just return back a subset
2290 * of the original tvbuff (which must be passed in).
2291 */
2292 fd_head->len = frag_data_len;
2293 fd_head->reassembled_in=pinfo->num;
2294 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
2295 return fd_head;
2296 }
2297
2298 orig_key = insert_fd_head(table, fd_head, pinfo, id, data);
2299 if (orig_keyp != NULL((void*)0))
2300 *orig_keyp = orig_key;
2301
2302 /*
2303 * If we weren't given an initial fragment number,
2304 * make it 0.
2305 */
2306 if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001)
2307 frag_number = 0;
2308 } else {
2309 if (orig_keyp != NULL((void*)0))
2310 *orig_keyp = orig_key;
2311
2312 /*
2313 * XXX If fd_head exists, but nothing has been added to it,
2314 * i.e. it was created with a known datalen with
2315 * fragment_start_seq_check, we should also be able to
2316 * do the memory saving trick as in the case above
2317 * when first creating it.
2318 */
2319 if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001) {
2320 fragment_item *fd;
2321 /*
2322 * If we weren't given an initial fragment number,
2323 * use the next expected fragment number as the fragment
2324 * number for this fragment.
2325 *
2326 * XXX - Use fd_head->first_gap to speed this up?
2327 */
2328 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next) {
2329 if (fd->next == NULL((void*)0))
2330 frag_number = fd->offset + 1;
2331 }
2332 }
2333 }
2334
2335 if (fragment_add_seq_work(fd_head, tvb, offset, pinfo,
2336 frag_number, frag_data_len, more_frags)) {
2337 /*
2338 * Reassembly is complete.
2339 */
2340 return fd_head;
2341 } else {
2342 /*
2343 * Reassembly isn't complete.
2344 */
2345 return NULL((void*)0);
2346 }
2347}
2348
2349fragment_head *
2350fragment_add_seq(reassembly_table *table, tvbuff_t *tvb, const int offset,
2351 const packet_info *pinfo, const uint32_t id, const void *data,
2352 const uint32_t frag_number, const uint32_t frag_data_len,
2353 const bool_Bool more_frags, const uint32_t flags)
2354{
2355 return fragment_add_seq_common(table, tvb, offset, pinfo, id, data,
2356 frag_number, frag_data_len,
2357 more_frags, flags, NULL((void*)0));
2358}
2359
2360/*
2361 * This does the work for "fragment_add_seq_check()" and
2362 * "fragment_add_seq_next()".
2363 *
2364 * This function assumes frag_number being a block sequence number.
2365 * The bsn for the first block is 0.
2366 *
2367 * If REASSEMBLE_FLAGS_NO_FRAG_NUMBER, it uses the next expected fragment number
2368 * as the fragment number if there is a reassembly in progress, otherwise
2369 * it uses 0.
2370 *
2371 * If not REASSEMBLE_FLAGS_NO_FRAG_NUMBER, it uses the "frag_number" argument as
2372 * the fragment number.
2373 *
2374 * If this is the first fragment seen for this datagram, a new
2375 * "fragment_head" structure is allocated to refer to the reassembled
2376 * packet.
2377 *
2378 * This fragment is added to the linked list of fragments for this packet.
2379 *
2380 * If "more_frags" is false and REASSEMBLE_FLAGS_802_11_HACK (as the name
2381 * implies, a special hack for 802.11) or REASSEMBLE_FLAGS_NO_FRAG_NUMBER
2382 * (implying messages must be in order since there's no sequence number) are
2383 * set in "flags", then this (one element) list is returned.
2384 *
2385 * If, after processing this fragment, we have all the fragments,
2386 * "fragment_add_seq_check_work()" removes that from the fragment hash
2387 * table if necessary and adds it to the table of reassembled fragments,
2388 * and returns a pointer to the head of the fragment list.
2389 *
2390 * Otherwise, it returns NULL.
2391 *
2392 * XXX - Should we simply return NULL for zero-length fragments?
2393 */
2394static fragment_head *
2395fragment_add_seq_check_work(reassembly_table *table, tvbuff_t *tvb,
2396 const int offset, const packet_info *pinfo,
2397 const uint32_t id, const void *data,
2398 const uint32_t frag_number,
2399 const uint32_t frag_data_len,
2400 const bool_Bool more_frags, const uint32_t flags)
2401{
2402 reassembled_key reass_key;
2403 fragment_head *fd_head;
2404 void *orig_key;
2405
2406 /*
2407 * Have we already seen this frame?
2408 * If so, look for it in the table of reassembled packets.
2409 */
2410 if (pinfo->fd->visited) {
2411 reass_key.frame = pinfo->num;
2412 reass_key.id = id;
2413 return (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
2414 }
2415
2416 fd_head = fragment_add_seq_common(table, tvb, offset, pinfo, id, data,
2417 frag_number, frag_data_len,
2418 more_frags,
2419 flags,
2420 &orig_key);
2421 if (fd_head) {
2422 /*
2423 * Reassembly is complete.
2424 *
2425 * If this is in the table of in-progress reassemblies,
2426 * remove it from that table. (It could be that this
2427 * was the first and last fragment, so that no
2428 * reassembly was done.)
2429 */
2430 if (orig_key != NULL((void*)0))
2431 fragment_unhash(table, orig_key);
2432
2433 /*
2434 * Add this item to the table of reassembled packets.
2435 */
2436 fragment_reassembled(table, fd_head, pinfo, id);
2437 return fd_head;
2438 } else {
2439 /*
2440 * Reassembly isn't complete.
2441 */
2442 return NULL((void*)0);
2443 }
2444}
2445
2446fragment_head *
2447fragment_add_seq_check(reassembly_table *table, tvbuff_t *tvb, const int offset,
2448 const packet_info *pinfo, const uint32_t id,
2449 const void *data,
2450 const uint32_t frag_number, const uint32_t frag_data_len,
2451 const bool_Bool more_frags)
2452{
2453 return fragment_add_seq_check_work(table, tvb, offset, pinfo, id, data,
2454 frag_number, frag_data_len,
2455 more_frags, 0);
2456}
2457
2458fragment_head *
2459fragment_add_seq_802_11(reassembly_table *table, tvbuff_t *tvb,
2460 const int offset, const packet_info *pinfo,
2461 const uint32_t id, const void *data,
2462 const uint32_t frag_number, const uint32_t frag_data_len,
2463 const bool_Bool more_frags)
2464{
2465 return fragment_add_seq_check_work(table, tvb, offset, pinfo, id, data,
2466 frag_number, frag_data_len,
2467 more_frags,
2468 REASSEMBLE_FLAGS_802_11_HACK0x0002);
2469}
2470
2471fragment_head *
2472fragment_add_seq_next(reassembly_table *table, tvbuff_t *tvb, const int offset,
2473 const packet_info *pinfo, const uint32_t id,
2474 const void *data, const uint32_t frag_data_len,
2475 const bool_Bool more_frags)
2476{
2477 /* Use a dummy frag_number (0), it is ignored since
2478 * REASSEMBLE_FLAGS_NO_FRAG_NUMBER is set. */
2479 return fragment_add_seq_check_work(table, tvb, offset, pinfo, id, data,
2480 0, frag_data_len, more_frags,
2481 REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001);
2482}
2483
2484static void
2485fragment_add_seq_single_move(reassembly_table *table, const packet_info *pinfo,
2486 const uint32_t id, const void *data,
2487 const uint32_t offset)
2488{
2489 fragment_head *fh, *new_fh;
2490 fragment_item *fd, *prev_fd;
2491 tvbuff_t *old_tvb_data;
2492 if (offset == 0) {
2493 return;
2494 }
2495 fh = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
2496 if (fh == NULL((void*)0)) {
2497 /* Shouldn't be called this way.
2498 * Probably wouldn't hurt to just create fh in this case. */
2499 ws_assert_not_reached()ws_log_fatal_full("", LOG_LEVEL_ERROR, "epan/reassemble.c", 2499
, __func__, "assertion \"not reached\" failed")
;
2500 return;
2501 }
2502 if (fh->flags & FD_DATALEN_SET0x0400 && fh->datalen <= offset) {
2503 /* Don't take from past the end. <= because we don't
2504 * want to take a First fragment from the next one
2505 * either */
2506 return;
2507 }
2508 new_fh = lookup_fd_head(table, pinfo, id+offset, data, NULL((void*)0));
2509 if (new_fh != NULL((void*)0)) {
2510 /* Attach to the end of the sorted list. */
2511 prev_fd = NULL((void*)0);
2512 for(fd = fh->next; fd != NULL((void*)0); fd=fd->next) {
2513 prev_fd = fd;
2514 }
2515 /* Don't take a reassembly starting with a First fragment. */
2516 fd = new_fh->next;
2517 if (fd && fd->offset != 0) {
2518 fragment_item *inserted = fd;
2519 bool_Bool multi_insert = (inserted->next != NULL((void*)0));
2520 if (prev_fd) {
2521 prev_fd->next = fd;
2522 } else {
2523 fh->next = fd;
2524 }
2525 for (; fd; fd=fd->next) {
2526 fd->offset += offset;
2527 if (fh->frame < fd->frame) {
2528 fh->frame = fd->frame;
2529 }
2530 }
2531 update_first_gap(fh, inserted, multi_insert);
2532 /* If previously found a Last fragment,
2533 * transfer that info to the new one. */
2534 if (new_fh->flags & FD_DATALEN_SET0x0400) {
2535 fh->flags |= FD_DATALEN_SET0x0400;
2536 fh->datalen = new_fh->datalen + offset;
2537 }
2538 /* Now remove and delete */
2539 new_fh->next = NULL((void*)0);
2540 old_tvb_data = fragment_delete(table, pinfo, id+offset, data);
2541 if (old_tvb_data)
2542 tvb_free(old_tvb_data);
2543 }
2544 }
2545}
2546
2547static fragment_head *
2548fragment_add_seq_single_work(reassembly_table *table, tvbuff_t *tvb,
2549 const int offset, const packet_info *pinfo,
2550 const uint32_t id, const void* data,
2551 const uint32_t frag_data_len,
2552 const bool_Bool first, const bool_Bool last,
2553 const uint32_t max_frags, const uint32_t max_age,
2554 const uint32_t flags)
2555{
2556 reassembled_key reass_key;
2557 tvbuff_t *old_tvb_data;
2558 void *orig_key;
2559 fragment_head *fh, *new_fh;
2560 fragment_item *fd, *prev_fd;
2561 uint32_t frag_number, tmp_offset;
2562 /* Have we already seen this frame?
2563 * If so, look for it in the table of reassembled packets.
2564 * Note here we store in the reassembly table by the single sequence
2565 * number rather than the sequence number of the First fragment. */
2566 if (pinfo->fd->visited) {
2567 reass_key.frame = pinfo->num;
2568 reass_key.id = id;
2569 fh = (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
2570 return fh;
2571 }
2572 /* First let's figure out where we want to add our new fragment */
2573 fh = NULL((void*)0);
2574 if (first) {
2575 frag_number = 0;
2576 fh = lookup_fd_head(table, pinfo, id-frag_number, data, NULL((void*)0));
2577 if ((flags & REASSEMBLE_FLAGS_AGING0x0001) &&
2578 fh && ((fh->frame + max_age) < pinfo->num)) {
2579 old_tvb_data = fragment_delete(table, pinfo, id-frag_number, data);
2580 if (old_tvb_data)
2581 tvb_free(old_tvb_data);
2582 fh = NULL((void*)0);
2583 }
2584 if (fh == NULL((void*)0)) {
2585 /* Not found. Create list-head. */
2586 fh = new_head(FD_BLOCKSEQUENCE0x0100);
2587 insert_fd_head(table, fh, pinfo, id-frag_number, data);
2588 }
2589 /* As this is the first fragment, we might have added segments
2590 * for this reassembly to the previous one in-progress. */
2591 fd = NULL((void*)0);
2592 for (frag_number=1; frag_number < max_frags; frag_number++) {
2593 new_fh = lookup_fd_head(table, pinfo, id-frag_number, data, NULL((void*)0));
2594 if (new_fh != NULL((void*)0)) {
2595 prev_fd = NULL((void*)0);
2596 new_fh->frame = 0;
2597 for (fd=new_fh->next; fd && fd->offset < frag_number; fd=fd->next) {
2598 prev_fd = fd;
2599 if (new_fh->frame < fd->frame) {
2600 new_fh->frame = fd->frame;
2601 }
2602 }
2603 if (prev_fd) {
2604 prev_fd->next = NULL((void*)0);
2605 } else {
2606 new_fh->next = NULL((void*)0);
2607 }
2608 fragment_items_removed(new_fh, prev_fd);
2609 break;
2610 }
2611 }
2612 if (fd != NULL((void*)0)) {
2613 tmp_offset = 0;
2614 for (prev_fd = fd; prev_fd; prev_fd = prev_fd->next) {
2615 prev_fd->offset -= frag_number;
2616 tmp_offset = prev_fd->offset;
2617 if (fh->frame < prev_fd->frame) {
2618 fh->frame = prev_fd->frame;
2619 }
2620 }
2621 MERGE_FRAG(fh, fd);
2622 if (new_fh != NULL((void*)0)) {
2623 /* If we've moved a Last packet, change datalen.
2624 * Second part of this test prob. redundant? */
2625 if (new_fh->flags & FD_DATALEN_SET0x0400 &&
2626 new_fh->datalen >= frag_number) {
2627 fh->flags |= FD_DATALEN_SET0x0400;
2628 fh->datalen = new_fh->datalen - frag_number;
2629 new_fh->flags &= ~FD_DATALEN_SET0x0400;
2630 new_fh->datalen = 0;
2631 }
2632 /* If we've moved all the fragments,
2633 * delete the old head */
2634 if (new_fh->next == NULL((void*)0)) {
2635 old_tvb_data = fragment_delete(table, pinfo, id-frag_number, data);
2636 if (old_tvb_data)
2637 tvb_free(old_tvb_data);
2638 }
2639 } else {
2640 /* Look forward and take off the next (this is
2641 * necessary in some edge cases where max_frags
2642 * prevented some fragments from going on the
2643 * previous First, but they can go on this one. */
2644 fragment_add_seq_single_move(table, pinfo, id,
2645 data, tmp_offset);
2646 }
2647 }
2648 frag_number = 0; /* For the rest of the function */
2649 } else {
2650 for (frag_number=1; frag_number < max_frags; frag_number++) {
2651 fh = lookup_fd_head(table, pinfo, id-frag_number, data, NULL((void*)0));
2652 if ((flags & REASSEMBLE_FLAGS_AGING0x0001) &&
2653 fh && ((fh->frame + max_age) < pinfo->num)) {
2654 old_tvb_data = fragment_delete(table, pinfo, id-frag_number, data);
2655 if (old_tvb_data)
2656 tvb_free(old_tvb_data);
2657 fh = NULL((void*)0);
2658 }
2659 if (fh != NULL((void*)0)) {
2660 if (fh->flags & FD_DATALEN_SET0x0400 &&
2661 fh->datalen < frag_number) {
2662 /* This fragment is after the Last
2663 * fragment, so must go after here. */
2664 fh = NULL((void*)0);
2665 }
2666 break;
2667 }
2668 }
2669 if (fh == NULL((void*)0)) { /* Didn't find location, use default */
2670 frag_number = 1;
2671 /* Already looked for frag_number 1, so just create */
2672 fh = new_head(FD_BLOCKSEQUENCE0x0100);
2673 insert_fd_head(table, fh, pinfo, id-frag_number, data);
2674 }
2675 }
2676 if (last) {
2677 /* Look for fragments past the end set by this Last fragment. */
2678 prev_fd = NULL((void*)0);
2679 for (fd=fh->next; fd && fd->offset <= frag_number; fd=fd->next) {
2680 prev_fd = fd;
2681 }
2682 /* fd is now all fragments offset > frag_number (the Last).
2683 * It shouldn't have a fragment with offset frag_number+1,
2684 * as that would be a First fragment not marked as such.
2685 * However, this can happen if we had unreassembled fragments
2686 * (missing, or at the start of the capture) and we've also
2687 * looped around on the sequence numbers. It can also happen
2688 * if bit errors mess up Last or First. */
2689 if (fd != NULL((void*)0)) {
2690 if (prev_fd) {
2691 prev_fd->next = NULL((void*)0);
2692 } else {
2693 fh->next = NULL((void*)0);
2694 }
2695 fragment_items_removed(fh, prev_fd);
2696 fh->frame = 0;
2697 for (prev_fd=fh->next; prev_fd; prev_fd=prev_fd->next) {
2698 if (fh->frame < prev_fd->frame) {
2699 fh->frame = prev_fd->frame;
2700 }
2701 }
2702 while (fd && fd->offset == frag_number+1) {
2703 /* Definitely have bad data here. Best to
2704 * delete these and leave unreassembled. */
2705 fd = fragment_item_free(fd);
2706 }
2707 }
2708 if (fd != NULL((void*)0)) {
2709 /* Move these onto the next frame. */
2710 new_fh = lookup_fd_head(table, pinfo, id+1, data, NULL((void*)0));
2711 if (new_fh==NULL((void*)0)) {
2712 /* Not found. Create list-head. */
2713 new_fh = new_head(FD_BLOCKSEQUENCE0x0100);
2714 insert_fd_head(table, new_fh, pinfo, id+1, data);
2715 }
2716 tmp_offset = 0;
2717 for (prev_fd = fd; prev_fd; prev_fd = prev_fd->next) {
2718 prev_fd->offset -= (frag_number+1);
2719 tmp_offset = prev_fd->offset;
2720 if (new_fh->frame < fd->frame) {
2721 new_fh->frame = fd->frame;
2722 }
2723 }
2724 MERGE_FRAG(new_fh, fd);
2725 /* If we previously found a different Last fragment,
2726 * transfer that information to the new reassembly. */
2727 if (fh->flags & FD_DATALEN_SET0x0400 &&
2728 fh->datalen > frag_number) {
2729 new_fh->flags |= FD_DATALEN_SET0x0400;
2730 new_fh->datalen = fh->datalen - (frag_number+1);
2731 fh->flags &= ~FD_DATALEN_SET0x0400;
2732 fh->datalen = 0;
2733 } else {
2734 /* Look forward and take off the next (this is
2735 * necessary in some edge cases where max_frags
2736 * prevented some fragments from going on the
2737 * previous First, but they can go on this one. */
2738 fragment_add_seq_single_move(table, pinfo, id+1,
2739 data, tmp_offset);
2740 }
2741 }
2742 } else {
2743 fragment_add_seq_single_move(table, pinfo, id-frag_number, data,
2744 frag_number+1);
2745 }
2746 /* Having cleaned up everything, finally ready to add our new
2747 * fragment. Note that only this will ever complete a reassembly. */
2748 fh = fragment_add_seq_common(table, tvb, offset, pinfo,
2749 id-frag_number, data,
2750 frag_number, frag_data_len,
2751 !last, 0, &orig_key);
2752 if (fh) {
2753 /*
2754 * Reassembly is complete.
2755 *
2756 * If this is in the table of in-progress reassemblies,
2757 * remove it from that table. (It could be that this
2758 * was the first and last fragment, so that no
2759 * reassembly was done.)
2760 */
2761 if (orig_key != NULL((void*)0))
2762 fragment_unhash(table, orig_key);
2763
2764 /*
2765 * Add this item to the table of reassembled packets.
2766 */
2767 fragment_reassembled_single(table, fh, pinfo, id-frag_number);
2768 return fh;
2769 } else {
2770 /*
2771 * Reassembly isn't complete.
2772 */
2773 return NULL((void*)0);
2774 }
2775}
2776
2777fragment_head *
2778fragment_add_seq_single(reassembly_table *table, tvbuff_t *tvb,
2779 const int offset, const packet_info *pinfo,
2780 const uint32_t id, const void* data,
2781 const uint32_t frag_data_len,
2782 const bool_Bool first, const bool_Bool last,
2783 const uint32_t max_frags)
2784{
2785 return fragment_add_seq_single_work(table, tvb, offset, pinfo,
2786 id, data, frag_data_len,
2787 first, last, max_frags, 0, 0);
2788}
2789
2790fragment_head *
2791fragment_add_seq_single_aging(reassembly_table *table, tvbuff_t *tvb,
2792 const int offset, const packet_info *pinfo,
2793 const uint32_t id, const void* data,
2794 const uint32_t frag_data_len,
2795 const bool_Bool first, const bool_Bool last,
2796 const uint32_t max_frags, const uint32_t max_age)
2797{
2798 return fragment_add_seq_single_work(table, tvb, offset, pinfo,
2799 id, data, frag_data_len,
2800 first, last, max_frags, max_age,
2801 REASSEMBLE_FLAGS_AGING0x0001);
2802}
2803
2804void
2805fragment_start_seq_check(reassembly_table *table, const packet_info *pinfo,
2806 const uint32_t id, const void *data,
2807 const uint32_t tot_len)
2808{
2809 fragment_head *fd_head;
2810
2811 /* Have we already seen this frame ?*/
2812 if (pinfo->fd->visited) {
2813 return;
2814 }
2815
2816 /* Check if fragment data exists */
2817 fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
2818
2819 if (fd_head == NULL((void*)0)) {
2820 /* Create list-head. */
2821 fd_head = new_head(FD_BLOCKSEQUENCE0x0100|FD_DATALEN_SET0x0400);
2822 fd_head->datalen = tot_len;
2823
2824 insert_fd_head(table, fd_head, pinfo, id, data);
2825 }
2826}
2827
2828fragment_head *
2829fragment_end_seq_next(reassembly_table *table, const packet_info *pinfo,
2830 const uint32_t id, const void *data)
2831{
2832 reassembled_key reass_key;
2833 reassembled_key *new_key;
2834 fragment_head *fd_head;
2835 fragment_item *fd;
2836 void *orig_key;
2837 uint32_t max_offset = 0;
2838
2839 /*
2840 * Have we already seen this frame?
2841 * If so, look for it in the table of reassembled packets.
2842 */
2843 if (pinfo->fd->visited) {
1
Assuming field 'visited' is 0
2
Taking false branch
2844 reass_key.frame = pinfo->num;
2845 reass_key.id = id;
2846 return (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
2847 }
2848
2849 fd_head = lookup_fd_head(table, pinfo, id, data, &orig_key);
2850
2851 if (fd_head) {
3
Assuming 'fd_head' is non-null
4
Taking true branch
2852 for (fd = fd_head->next; fd; fd = fd->next) {
5
Loop condition is false. Execution continues on line 2857
2853 if (fd->offset > max_offset) {
2854 max_offset = fd->offset;
2855 }
2856 }
2857 fd_head->datalen = max_offset;
2858 fd_head->flags |= FD_DATALEN_SET0x0400;
2859
2860 fragment_defragment_and_free (fd_head, pinfo);
6
Calling 'fragment_defragment_and_free'
2861
2862 /*
2863 * Remove this from the table of in-progress reassemblies,
2864 * and free up any memory used for it in that table.
2865 */
2866 fragment_unhash(table, orig_key);
2867
2868 /*
2869 * Add this item to the table of reassembled packets.
2870 */
2871 fragment_reassembled(table, fd_head, pinfo, id);
2872 if (fd_head->next != NULL((void*)0)) {
2873 new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc ((sizeof (reassembled_key) >
0 ? sizeof (reassembled_key) : 1)))
;
2874 new_key->frame = pinfo->num;
2875 new_key->id = id;
2876 reassembled_table_insert(table->reassembled_table, new_key, fd_head);
2877 }
2878
2879 return fd_head;
2880 } else {
2881 /*
2882 * Fragment data not found.
2883 */
2884 return NULL((void*)0);
2885 }
2886}
2887
2888/*
2889 * Process reassembled data; if we're on the frame in which the data
2890 * was reassembled, put the fragment information into the protocol
2891 * tree, and construct a tvbuff with the reassembled data, otherwise
2892 * just put a "reassembled in" item into the protocol tree.
2893 * offset from start of tvb, result up to end of tvb
2894 */
2895tvbuff_t *
2896process_reassembled_data(tvbuff_t *tvb, const int offset, packet_info *pinfo,
2897 const char *name, fragment_head *fd_head, const fragment_items *fit,
2898 bool_Bool *update_col_infop, proto_tree *tree)
2899{
2900 tvbuff_t *next_tvb;
2901 bool_Bool update_col_info;
2902 proto_item *frag_tree_item;
2903
2904 if (fd_head != NULL((void*)0) && pinfo->num == fd_head->reassembled_in && pinfo->curr_layer_num == fd_head->reas_in_layer_num) {
2905 /*
2906 * OK, we've reassembled this.
2907 * Is this something that's been reassembled from more
2908 * than one fragment?
2909 */
2910 if (fd_head->next != NULL((void*)0)) {
2911 /*
2912 * Yes.
2913 * Allocate a new tvbuff, referring to the
2914 * reassembled payload, and set
2915 * the tvbuff to the list of tvbuffs to which
2916 * the tvbuff we were handed refers, so it'll get
2917 * cleaned up when that tvbuff is cleaned up.
2918 */
2919 next_tvb = tvb_new_chain(tvb, fd_head->tvb_data);
2920
2921 /* Add the defragmented data to the data source list. */
2922 add_new_data_source(pinfo, next_tvb, name);
2923
2924 /* show all fragments */
2925 if (fd_head->flags & FD_BLOCKSEQUENCE0x0100) {
2926 update_col_info = !show_fragment_seq_tree(
2927 fd_head, fit, tree, pinfo, next_tvb, &frag_tree_item);
2928 } else {
2929 update_col_info = !show_fragment_tree(fd_head,
2930 fit, tree, pinfo, next_tvb, &frag_tree_item);
2931 }
2932 } else {
2933 /*
2934 * No.
2935 * Return a tvbuff with the payload, a subset of the
2936 * tvbuff passed in. (The dissector SHOULD pass in
2937 * the correct tvbuff and offset.)
2938 */
2939 int len;
2940 /* For FD_BLOCKSEQUENCE, len is the length in bytes,
2941 * datalen is the number of fragments.
2942 */
2943 if (fd_head->flags & FD_BLOCKSEQUENCE0x0100) {
2944 len = fd_head->len;
2945 } else {
2946 len = fd_head->datalen;
2947 }
2948 next_tvb = tvb_new_subset_length(tvb, offset, len);
2949 pinfo->fragmented = false0; /* one-fragment packet */
2950 update_col_info = true1;
2951 }
2952 if (update_col_infop != NULL((void*)0))
2953 *update_col_infop = update_col_info;
2954 } else {
2955 /*
2956 * We don't have the complete reassembled payload, or this
2957 * isn't the final frame of that payload.
2958 */
2959 next_tvb = NULL((void*)0);
2960
2961 /*
2962 * If we know what frame this was reassembled in,
2963 * and if there's a field to use for the number of
2964 * the frame in which the packet was reassembled,
2965 * add it to the protocol tree.
2966 */
2967 if (fd_head != NULL((void*)0) && fit->hf_reassembled_in != NULL((void*)0)) {
2968 proto_item *fei = proto_tree_add_uint(tree,
2969 *(fit->hf_reassembled_in), tvb,
2970 0, 0, fd_head->reassembled_in);
2971 proto_item_set_generated(fei);
2972 }
2973 }
2974 return next_tvb;
2975}
2976
2977/*
2978 * Show a single fragment in a fragment subtree, and put information about
2979 * it in the top-level item for that subtree.
2980 */
2981static void
2982show_fragment(fragment_item *fd, const int offset, const fragment_items *fit,
2983 proto_tree *ft, proto_item *fi, const bool_Bool first_frag,
2984 const uint32_t count, tvbuff_t *tvb, packet_info *pinfo)
2985{
2986 proto_item *fei=NULL((void*)0);
2987 int hf;
2988
2989 if (first_frag) {
2990 char *name;
2991 if (count == 1) {
2992 name = g_strdup(proto_registrar_get_name(*(fit->hf_fragment)))g_strdup_inline (proto_registrar_get_name(*(fit->hf_fragment
)))
;
2993 } else {
2994 name = g_strdup(proto_registrar_get_name(*(fit->hf_fragments)))g_strdup_inline (proto_registrar_get_name(*(fit->hf_fragments
)))
;
2995 }
2996 proto_item_set_text(fi, "%u %s (%u byte%s): ", count, name, tvb_captured_length(tvb),
2997 plurality(tvb_captured_length(tvb), "", "s")((tvb_captured_length(tvb)) == 1 ? ("") : ("s")));
2998 g_free(name)(__builtin_object_size ((name), 0) != ((size_t) - 1)) ? g_free_sized
(name, __builtin_object_size ((name), 0)) : (g_free) (name)
;
2999 } else {
3000 proto_item_append_text(fi, ", ");
3001 }
3002 proto_item_append_text(fi, "#%u(%u)", fd->frame, fd->len);
3003
3004 if (fd->flags & (FD_OVERLAPCONFLICT0x0004
3005 |FD_MULTIPLETAILS0x0008|FD_TOOLONGFRAGMENT0x0010) ) {
3006 hf = *(fit->hf_fragment_error);
3007 } else {
3008 hf = *(fit->hf_fragment);
3009 }
3010 if (fd->len == 0) {
3011 fei = proto_tree_add_uint_format(ft, hf,
3012 tvb, offset, fd->len,
3013 fd->frame,
3014 "Frame: %u (no data)",
3015 fd->frame);
3016 } else {
3017 fei = proto_tree_add_uint_format(ft, hf,
3018 tvb, offset, fd->len,
3019 fd->frame,
3020 "Frame: %u, payload: %u-%u (%u byte%s)",
3021 fd->frame,
3022 offset,
3023 offset+fd->len-1,
3024 fd->len,
3025 plurality(fd->len, "", "s")((fd->len) == 1 ? ("") : ("s")));
3026 }
3027 proto_item_set_generated(fei);
3028 mark_frame_as_depended_upon(pinfo->fd, fd->frame);
3029 if (fd->flags & (FD_OVERLAP0x0002|FD_OVERLAPCONFLICT0x0004
3030 |FD_MULTIPLETAILS0x0008|FD_TOOLONGFRAGMENT0x0010) ) {
3031 /* this fragment has some flags set, create a subtree
3032 * for it and display the flags.
3033 */
3034 proto_tree *fet=NULL((void*)0);
3035
3036 fet = proto_item_add_subtree(fei, *(fit->ett_fragment));
3037 if (fd->flags&FD_OVERLAP0x0002) {
3038 fei=proto_tree_add_boolean(fet,
3039 *(fit->hf_fragment_overlap),
3040 tvb, 0, 0,
3041 true1);
3042 proto_item_set_generated(fei);
3043 }
3044 if (fd->flags&FD_OVERLAPCONFLICT0x0004) {
3045 fei=proto_tree_add_boolean(fet,
3046 *(fit->hf_fragment_overlap_conflict),
3047 tvb, 0, 0,
3048 true1);
3049 proto_item_set_generated(fei);
3050 }
3051 if (fd->flags&FD_MULTIPLETAILS0x0008) {
3052 fei=proto_tree_add_boolean(fet,
3053 *(fit->hf_fragment_multiple_tails),
3054 tvb, 0, 0,
3055 true1);
3056 proto_item_set_generated(fei);
3057 }
3058 if (fd->flags&FD_TOOLONGFRAGMENT0x0010) {
3059 fei=proto_tree_add_boolean(fet,
3060 *(fit->hf_fragment_too_long_fragment),
3061 tvb, 0, 0,
3062 true1);
3063 proto_item_set_generated(fei);
3064 }
3065 }
3066}
3067
3068static bool_Bool
3069show_fragment_errs_in_col(fragment_head *fd_head, const fragment_items *fit,
3070 packet_info *pinfo)
3071{
3072 if (fd_head->flags & (FD_OVERLAPCONFLICT0x0004
3073 |FD_MULTIPLETAILS0x0008|FD_TOOLONGFRAGMENT0x0010) ) {
3074 col_add_fstr(pinfo->cinfo, COL_INFO, "[Illegal %s]", fit->tag);
3075 return true1;
3076 }
3077
3078 return false0;
3079}
3080
3081/* This function will build the fragment subtree; it's for fragments
3082 reassembled with "fragment_add()".
3083
3084 It will return true if there were fragmentation errors
3085 or false if fragmentation was ok.
3086*/
3087bool_Bool
3088show_fragment_tree(fragment_head *fd_head, const fragment_items *fit,
3089 proto_tree *tree, packet_info *pinfo, tvbuff_t *tvb, proto_item **fi)
3090{
3091 fragment_item *fd;
3092 proto_tree *ft;
3093 bool_Bool first_frag;
3094 uint32_t count = 0;
3095 /* It's not fragmented. */
3096 pinfo->fragmented = false0;
3097
3098 *fi = proto_tree_add_item(tree, *(fit->hf_fragments), tvb, 0, -1, ENC_NA0x00000000);
3099 proto_item_set_generated(*fi);
3100
3101 ft = proto_item_add_subtree(*fi, *(fit->ett_fragments));
3102 first_frag = true1;
3103 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next) {
3104 count++;
3105 }
3106 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next) {
3107 show_fragment(fd, fd->offset, fit, ft, *fi, first_frag, count, tvb, pinfo);
3108 first_frag = false0;
3109 }
3110
3111 if (fit->hf_fragment_count) {
3112 proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_fragment_count),
3113 tvb, 0, 0, count);
3114 proto_item_set_generated(fli);
3115 }
3116
3117 if (fit->hf_reassembled_length) {
3118 proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_reassembled_length),
3119 tvb, 0, 0, tvb_captured_length (tvb));
3120 proto_item_set_generated(fli);
3121 }
3122
3123 if (fit->hf_reassembled_data) {
3124 proto_item *fli = proto_tree_add_item(ft, *(fit->hf_reassembled_data),
3125 tvb, 0, tvb_captured_length(tvb), ENC_NA0x00000000);
3126 proto_item_set_generated(fli);
3127 }
3128
3129 return show_fragment_errs_in_col(fd_head, fit, pinfo);
3130}
3131
3132/* This function will build the fragment subtree; it's for fragments
3133 reassembled with "fragment_add_seq()" or "fragment_add_seq_check()".
3134
3135 It will return true if there were fragmentation errors
3136 or false if fragmentation was ok.
3137*/
3138bool_Bool
3139show_fragment_seq_tree(fragment_head *fd_head, const fragment_items *fit,
3140 proto_tree *tree, packet_info *pinfo, tvbuff_t *tvb, proto_item **fi)
3141{
3142 uint32_t offset, next_offset, count = 0;
3143 fragment_item *fd, *last_fd;
3144 proto_tree *ft;
3145 bool_Bool first_frag;
3146
3147 /* It's not fragmented. */
3148 pinfo->fragmented = false0;
3149
3150 *fi = proto_tree_add_item(tree, *(fit->hf_fragments), tvb, 0, -1, ENC_NA0x00000000);
3151 proto_item_set_generated(*fi);
3152
3153 ft = proto_item_add_subtree(*fi, *(fit->ett_fragments));
3154 offset = 0;
3155 next_offset = 0;
3156 last_fd = NULL((void*)0);
3157 first_frag = true1;
3158 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next){
3159 count++;
3160 }
3161 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next){
3162 if (last_fd == NULL((void*)0) || last_fd->offset != fd->offset) {
3163 offset = next_offset;
3164 next_offset += fd->len;
3165 }
3166 last_fd = fd;
3167 show_fragment(fd, offset, fit, ft, *fi, first_frag, count, tvb, pinfo);
3168 first_frag = false0;
3169 }
3170
3171 if (fit->hf_fragment_count) {
3172 proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_fragment_count),
3173 tvb, 0, 0, count);
3174 proto_item_set_generated(fli);
3175 }
3176
3177 if (fit->hf_reassembled_length) {
3178 proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_reassembled_length),
3179 tvb, 0, 0, tvb_captured_length (tvb));
3180 proto_item_set_generated(fli);
3181 }
3182
3183 if (fit->hf_reassembled_data) {
3184 proto_item *fli = proto_tree_add_item(ft, *(fit->hf_reassembled_data),
3185 tvb, 0, tvb_captured_length(tvb), ENC_NA0x00000000);
3186 proto_item_set_generated(fli);
3187 }
3188
3189 return show_fragment_errs_in_col(fd_head, fit, pinfo);
3190}
3191
3192static void
3193reassembly_table_init_reg_table(void *p, void *user_data _U___attribute__((unused)))
3194{
3195 register_reassembly_table_t* reg_table = (register_reassembly_table_t*)p;
3196 reassembly_table_init(reg_table->table, reg_table->funcs);
3197}
3198
3199static void
3200reassembly_table_init_reg_tables(void)
3201{
3202 g_list_foreach(reassembly_table_list, reassembly_table_init_reg_table, NULL((void*)0));
3203}
3204
3205static void
3206reassembly_table_cleanup_reg_table(void *p, void *user_data _U___attribute__((unused)))
3207{
3208 register_reassembly_table_t* reg_table = (register_reassembly_table_t*)p;
3209 reassembly_table_destroy(reg_table->table);
3210}
3211
3212static void
3213reassembly_table_cleanup_reg_tables(void)
3214{
3215 g_list_foreach(reassembly_table_list, reassembly_table_cleanup_reg_table, NULL((void*)0));
3216}
3217
3218void reassembly_tables_init(void)
3219{
3220 register_init_routine(&reassembly_table_init_reg_tables);
3221 register_cleanup_routine(&reassembly_table_cleanup_reg_tables);
3222}
3223
3224static void
3225reassembly_table_free(void *p, void *user_data _U___attribute__((unused)))
3226{
3227 register_reassembly_table_t* reg_table = (register_reassembly_table_t*)p;
3228 reassembly_table_destroy(reg_table->table);
3229 g_free(reg_table)(__builtin_object_size ((reg_table), 0) != ((size_t) - 1)) ? g_free_sized
(reg_table, __builtin_object_size ((reg_table), 0)) : (g_free
) (reg_table)
;
3230}
3231
3232void
3233reassembly_table_cleanup(void)
3234{
3235 g_list_foreach(reassembly_table_list, reassembly_table_free, NULL((void*)0));
3236 g_list_free(reassembly_table_list);
3237}
3238
3239/* One instance of this structure is created for each pdu that spans across
3240 * multiple segments. (MSP) */
3241typedef struct _multisegment_pdu_t {
3242 uint64_t first_frame;
3243 uint64_t last_frame;
3244 unsigned start_offset_at_first_frame;
3245 unsigned end_offset_at_last_frame;
3246 int length; /* length of this MSP */
3247 uint32_t streaming_reassembly_id;
3248 /* pointer to previous multisegment_pdu */
3249 struct _multisegment_pdu_t* prev_msp;
3250} multisegment_pdu_t;
3251
3252/* struct for keeping the reassembly information of each stream */
3253struct streaming_reassembly_info_t {
3254 /* This map is keyed by frame num and keeps track of all MSPs for this
3255 * stream. Different frames will point to the same MSP if they contain
3256 * part data of this MSP. If a frame contains data that
3257 * belongs to two MSPs, it will point to the second MSP. */
3258 wmem_map_t* multisegment_pdus;
3259 /* This map is keyed by frame num and keeps track of the frag_offset
3260 * of the first byte of frames for fragment_add() after first scan. */
3261 wmem_map_t* frame_num_frag_offset_map;
3262 /* how many bytes the current uncompleted MSP still needs. (only valid for first scan) */
3263 int prev_deseg_len;
3264 /* the current uncompleted MSP (only valid for first scan) */
3265 multisegment_pdu_t* last_msp;
3266};
3267
3268static uint32_t
3269create_streaming_reassembly_id(void)
3270{
3271 static uint32_t global_streaming_reassembly_id = 0;
3272 return ++global_streaming_reassembly_id;
3273}
3274
3275streaming_reassembly_info_t*
3276streaming_reassembly_info_new(void)
3277{
3278 return wmem_new0(wmem_file_scope(), streaming_reassembly_info_t)((streaming_reassembly_info_t*)wmem_alloc0((wmem_file_scope()
), sizeof(streaming_reassembly_info_t)))
;
3279}
3280
3281/* Following is an example of ProtoA and ProtoB protocols from the declaration of this function in 'reassemble.h':
3282 *
3283 * +------------------ A Multisegment PDU of ProtoB ----------------------+
3284 * | |
3285 * +--- ProtoA payload1 ---+ +- payload2 -+ +- Payload3 -+ +- Payload4 -+ +- ProtoA payload5 -+
3286 * | EoMSP | OmNFP | BoMSP | | MoMSP | | MoMSP | | MoMSP | | EoMSP | BoMSP |
3287 * +-------+-------+-------+ +------------+ +------------+ +------------+ +---------+---------+
3288 * | |
3289 * +----------------------------------------------------------------------+
3290 *
3291 * For a ProtoA payload composed of EoMSP + OmNFP + BoMSP will call fragment_add() twice on EoMSP and BoMSP; and call
3292 * process_reassembled_data() once for generating tvb of a MSP to which EoMSP belongs; and call subdissector twice on
3293 * reassembled MSP of EoMSP and OmNFP + BoMSP. After that finds BoMSP is a beginning of a MSP at first scan.
3294 *
3295 * The rules are:
3296 *
3297 * - If a ProtoA payload contains EoMSP, we will need call fragment_add(), process_reassembled_data() and subdissector
3298 * once on it to end a MSP. (May run twice or more times at first scan, because subdissector may only return the
3299 * head length of message by pinfo->desegment_len. We need run second time for subdissector to determine the length
3300 * of entire message).
3301 *
3302 * - If a ProtoA payload contains OmNFP, we will need only call subdissector once on it. The subdissector need dissect
3303 * all non-fragment PDUs in it. (no desegment_len should output)
3304 *
3305 * - If a ProtoA payload contains BoMSP, we will need call subdissector once on BoMSP or OmNFP+BoMSP (because unknown
3306 * during first scan). The subdissector will output desegment_len (!= 0). Then we will call fragment_add()
3307 * with a new reassembly id on BoMSP for starting a new MSP.
3308 *
3309 * - If a ProtoA payload only contains MoMSP (entire payload is part of a MSP), we will only call fragment_add() once
3310 * or twice (at first scan) on it. The subdissector will not be called.
3311 *
3312 * In this implementation, only multisegment PDUs are recorded in multisegment_pdus map keyed by the numbers (uint64_t)
3313 * of frames belongs to MSPs. Each MSP in the map has a pointer referred to previous MSP, because we may need
3314 * two MSPs to dissect a ProtoA payload that contains EoMSP + BoMSP at the same time. The multisegment_pdus map is built
3315 * during first scan (pinfo->visited == false) with help of prev_deseg_len and last_msp fields of streaming_reassembly_info_t
3316 * for each direction of a ProtoA STREAM. The prev_deseg_len record how many bytes of subsequent ProtoA payloads belong to
3317 * previous PDU during first scan. The last_msp member of streaming_reassembly_info_t is always point to last MSP which
3318 * is created during scan previous or early ProtoA payloads. Since subdissector might return only the head length of entire
3319 * message (by pinfo->desegment_len) when there is not enough data to determine the message length, we need to reopen
3320 * reassembly fragments for adding more bytes during scanning the next ProtoA payload. We have to use fragment_add()
3321 * instead of fragment_add_check() or fragment_add_seq_next().
3322 *
3323 * Read more: please refer to comments of the declaration of this function in 'reassemble.h'.
3324 */
3325int
3326reassemble_streaming_data_and_call_subdissector(
3327 tvbuff_t* tvb, packet_info* pinfo, unsigned offset, int length,
3328 proto_tree* segment_tree, proto_tree* reassembled_tree, reassembly_table streaming_reassembly_table,
3329 streaming_reassembly_info_t* reassembly_info, uint64_t cur_frame_num,
3330 dissector_handle_t subdissector_handle, proto_tree* subdissector_tree, void* subdissector_data,
3331 const char* label, const fragment_items* frag_hf_items, int hf_segment_data
3332)
3333{
3334 int orig_length = length;
3335 int datalen = 0;
3336 int bytes_belong_to_prev_msp = 0; /* bytes belong to previous MSP */
3337 uint32_t reassembly_id = 0, frag_offset = 0;
3338 fragment_head* head = NULL((void*)0);
3339 bool_Bool need_more = false0;
3340 bool_Bool found_BoMSP = false0;
3341 multisegment_pdu_t* cur_msp = NULL((void*)0), * prev_msp = NULL((void*)0);
3342 uint16_t save_can_desegment;
3343 int save_desegment_offset;
3344 uint32_t save_desegment_len;
3345 uint64_t* frame_ptr;
3346
3347 save_can_desegment = pinfo->can_desegment;
3348 save_desegment_offset = pinfo->desegment_offset;
3349 save_desegment_len = pinfo->desegment_len;
3350
3351 /* calculate how many bytes of this payload belongs to previous MSP (EoMSP) */
3352 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3353 /* this is first scan */
3354 if (reassembly_info->prev_deseg_len == DESEGMENT_ONE_MORE_SEGMENT0x0fffffff) {
3355 /* assuming the entire tvb belongs to the previous MSP */
3356 bytes_belong_to_prev_msp = length;
3357 reassembly_info->prev_deseg_len = length;
3358 } else if (reassembly_info->prev_deseg_len > 0) {
3359 /* part or all of current payload belong to previous MSP */
3360 bytes_belong_to_prev_msp = MIN(reassembly_info->prev_deseg_len, length)(((reassembly_info->prev_deseg_len) < (length)) ? (reassembly_info
->prev_deseg_len) : (length))
;
3361 reassembly_info->prev_deseg_len -= bytes_belong_to_prev_msp;
3362 need_more = (reassembly_info->prev_deseg_len > 0);
3363 } /* else { beginning of a new PDU (might be a NFP or MSP) } */
3364
3365 if (bytes_belong_to_prev_msp > 0) {
3366 DISSECTOR_ASSERT(reassembly_info->last_msp != NULL)((void) ((reassembly_info->last_msp != ((void*)0)) ? (void
)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/reassemble.c", 3366, "reassembly_info->last_msp != ((void*)0)"
))))
;
3367 reassembly_id = reassembly_info->last_msp->streaming_reassembly_id;
3368 frag_offset = reassembly_info->last_msp->length;
3369 if (reassembly_info->frame_num_frag_offset_map == NULL((void*)0)) {
3370 reassembly_info->frame_num_frag_offset_map = wmem_map_new(wmem_file_scope(), g_int64_hash, g_int64_equal);
3371 }
3372 frame_ptr = (uint64_t*)wmem_memdup(wmem_file_scope(), &cur_frame_num, sizeof(uint64_t));
3373 wmem_map_insert(reassembly_info->frame_num_frag_offset_map, frame_ptr, GUINT_TO_POINTER(frag_offset)((gpointer) (gulong) (frag_offset)));
3374 /* This payload contains the data of previous msp, so we point to it. That may be overridden late. */
3375 wmem_map_insert(reassembly_info->multisegment_pdus, frame_ptr, reassembly_info->last_msp);
3376 }
3377 } else {
3378 /* not first scan, use information of multisegment_pdus built during first scan */
3379 if (reassembly_info->multisegment_pdus) {
3380 cur_msp = (multisegment_pdu_t*)wmem_map_lookup(reassembly_info->multisegment_pdus, &cur_frame_num);
3381 }
3382 if (cur_msp) {
3383 if (cur_msp->first_frame == cur_frame_num) {
3384 /* Current payload contains a beginning of a MSP. (BoMSP)
3385 * The cur_msp contains information about the beginning MSP.
3386 * If prev_msp is not null, that means this payload also contains
3387 * the last part of previous MSP. (EoMSP) */
3388 prev_msp = cur_msp->prev_msp;
3389 } else {
3390 /* Current payload is not a first frame of a MSP (not include BoMSP). */
3391 prev_msp = cur_msp;
3392 cur_msp = NULL((void*)0);
3393 }
3394 }
3395
3396 if (prev_msp && prev_msp->last_frame >= cur_frame_num) {
3397 if (prev_msp->last_frame == cur_frame_num) {
3398 /* this payload contains part of previous MSP (contains EoMSP) */
3399 bytes_belong_to_prev_msp = prev_msp->end_offset_at_last_frame - offset;
3400 } else { /* if (prev_msp->last_frame > cur_frame_num) */
3401 /* this payload all belongs to previous MSP */
3402 bytes_belong_to_prev_msp = length;
3403 need_more = true1;
3404 }
3405 reassembly_id = prev_msp->streaming_reassembly_id;
3406 }
3407 if (reassembly_info->frame_num_frag_offset_map) {
3408 frag_offset = GPOINTER_TO_UINT(wmem_map_lookup(reassembly_info->frame_num_frag_offset_map, &cur_frame_num))((guint) (gulong) (wmem_map_lookup(reassembly_info->frame_num_frag_offset_map
, &cur_frame_num)))
;
3409 }
3410 }
3411
3412 /* handling EoMSP or MoMSP (entire payload being middle part of a MSP) */
3413 while (bytes_belong_to_prev_msp > 0) {
3414 tvbuff_t* reassembled_tvb = NULL((void*)0);
3415 DISSECTOR_ASSERT(reassembly_id > 0)((void) ((reassembly_id > 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3415,
"reassembly_id > 0"))))
;
3416 pinfo->can_desegment = 2; /* this will be decreased one while passing to subdissector */
3417 pinfo->desegment_offset = 0;
3418 pinfo->desegment_len = 0;
3419
3420 head = fragment_add(&streaming_reassembly_table, tvb, offset, pinfo, reassembly_id, NULL((void*)0),
3421 frag_offset, bytes_belong_to_prev_msp, need_more);
3422
3423 if (head) {
3424 if (frag_hf_items->hf_reassembled_in) {
3425 proto_item_set_generated(
3426 proto_tree_add_uint(segment_tree, *(frag_hf_items->hf_reassembled_in), tvb, offset,
3427 bytes_belong_to_prev_msp, head->reassembled_in)
3428 );
3429 }
3430
3431 if (!need_more) {
3432 reassembled_tvb = process_reassembled_data(tvb, offset, pinfo,
3433 wmem_strdup_printf(pinfo->pool, "Reassembled %s", label),
3434 head, frag_hf_items, NULL((void*)0), reassembled_tree);
3435 }
3436 }
3437
3438 proto_tree_add_bytes_format(segment_tree, hf_segment_data, tvb, offset,
3439 bytes_belong_to_prev_msp, NULL((void*)0), "%s Segment data (%u byte%s)", label,
3440 bytes_belong_to_prev_msp, plurality(bytes_belong_to_prev_msp, "", "s")((bytes_belong_to_prev_msp) == 1 ? ("") : ("s")));
3441
3442 if (reassembled_tvb) {
3443 /* normally, this stage will dissect one or more completed pdus */
3444 /* Note, don't call_dissector_with_data because sometime the pinfo->curr_layer_num will changed
3445 * after calling that will make reassembly failed! */
3446 call_dissector_only(subdissector_handle, reassembled_tvb, pinfo, subdissector_tree, subdissector_data);
3447 }
3448
3449 if (pinfo->desegment_len) {
3450 /* that must only happen during first scan the reassembly_info->prev_deseg_len might be only the
3451 * head length of entire message. */
3452 DISSECTOR_ASSERT(!PINFO_FD_VISITED(pinfo))((void) ((!((pinfo)->fd->visited)) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3452,
"!((pinfo)->fd->visited)"))))
;
3453 DISSECTOR_ASSERT_HINT(pinfo->desegment_len != DESEGMENT_UNTIL_FIN, "Subdissector MUST NOT "((void) ((pinfo->desegment_len != 0x0ffffffe) ? (void)0 : (
proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)"
, "epan/reassemble.c", 3455, "pinfo->desegment_len != 0x0ffffffe"
, "Subdissector MUST NOT " "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to "
" DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined."
))))
3454 "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to "((void) ((pinfo->desegment_len != 0x0ffffffe) ? (void)0 : (
proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)"
, "epan/reassemble.c", 3455, "pinfo->desegment_len != 0x0ffffffe"
, "Subdissector MUST NOT " "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to "
" DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined."
))))
3455 " DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined.")((void) ((pinfo->desegment_len != 0x0ffffffe) ? (void)0 : (
proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)"
, "epan/reassemble.c", 3455, "pinfo->desegment_len != 0x0ffffffe"
, "Subdissector MUST NOT " "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to "
" DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined."
))))
;
3456
3457 if (pinfo->desegment_offset > 0) {
3458 DISSECTOR_ASSERT_HINT(pinfo->desegment_offset > reassembly_info->last_msp->length((void) ((pinfo->desegment_offset > reassembly_info->
last_msp->length && pinfo->desegment_offset <
reassembly_info->last_msp->length + bytes_belong_to_prev_msp
) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)"
, "epan/reassemble.c", 3462, "pinfo->desegment_offset > reassembly_info->last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp"
, wmem_strdup_printf(pinfo->pool, "Subdissector MUST NOT set pinfo->desegment_offset(%d) in previous or next part of MSP, must between (%d, %d)."
, pinfo->desegment_offset, reassembly_info->last_msp->
length, reassembly_info->last_msp->length + bytes_belong_to_prev_msp
)))))
3459 && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp,((void) ((pinfo->desegment_offset > reassembly_info->
last_msp->length && pinfo->desegment_offset <
reassembly_info->last_msp->length + bytes_belong_to_prev_msp
) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)"
, "epan/reassemble.c", 3462, "pinfo->desegment_offset > reassembly_info->last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp"
, wmem_strdup_printf(pinfo->pool, "Subdissector MUST NOT set pinfo->desegment_offset(%d) in previous or next part of MSP, must between (%d, %d)."
, pinfo->desegment_offset, reassembly_info->last_msp->
length, reassembly_info->last_msp->length + bytes_belong_to_prev_msp
)))))
3460 wmem_strdup_printf(pinfo->pool,((void) ((pinfo->desegment_offset > reassembly_info->
last_msp->length && pinfo->desegment_offset <
reassembly_info->last_msp->length + bytes_belong_to_prev_msp
) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)"
, "epan/reassemble.c", 3462, "pinfo->desegment_offset > reassembly_info->last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp"
, wmem_strdup_printf(pinfo->pool, "Subdissector MUST NOT set pinfo->desegment_offset(%d) in previous or next part of MSP, must between (%d, %d)."
, pinfo->desegment_offset, reassembly_info->last_msp->
length, reassembly_info->last_msp->length + bytes_belong_to_prev_msp
)))))
3461 "Subdissector MUST NOT set pinfo->desegment_offset(%d) in previous or next part of MSP, must between (%d, %d).",((void) ((pinfo->desegment_offset > reassembly_info->
last_msp->length && pinfo->desegment_offset <
reassembly_info->last_msp->length + bytes_belong_to_prev_msp
) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)"
, "epan/reassemble.c", 3462, "pinfo->desegment_offset > reassembly_info->last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp"
, wmem_strdup_printf(pinfo->pool, "Subdissector MUST NOT set pinfo->desegment_offset(%d) in previous or next part of MSP, must between (%d, %d)."
, pinfo->desegment_offset, reassembly_info->last_msp->
length, reassembly_info->last_msp->length + bytes_belong_to_prev_msp
)))))
3462 pinfo->desegment_offset, reassembly_info->last_msp->length, reassembly_info->last_msp->length + bytes_belong_to_prev_msp))((void) ((pinfo->desegment_offset > reassembly_info->
last_msp->length && pinfo->desegment_offset <
reassembly_info->last_msp->length + bytes_belong_to_prev_msp
) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)"
, "epan/reassemble.c", 3462, "pinfo->desegment_offset > reassembly_info->last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp"
, wmem_strdup_printf(pinfo->pool, "Subdissector MUST NOT set pinfo->desegment_offset(%d) in previous or next part of MSP, must between (%d, %d)."
, pinfo->desegment_offset, reassembly_info->last_msp->
length, reassembly_info->last_msp->length + bytes_belong_to_prev_msp
)))))
;
3463
3464 /* shorten the bytes_belong_to_prev_msp and just truncate the reassembled tvb */
3465 bytes_belong_to_prev_msp = pinfo->desegment_offset - reassembly_info->last_msp->length;
3466 fragment_truncate(&streaming_reassembly_table, pinfo, reassembly_id, NULL((void*)0), pinfo->desegment_offset);
3467 found_BoMSP = true1;
3468 } else {
3469 if (pinfo->desegment_len == DESEGMENT_ONE_MORE_SEGMENT0x0fffffff) {
3470 /* just need more bytes, all remaining bytes belongs to previous MSP (to run fragment_add again) */
3471 bytes_belong_to_prev_msp = length;
3472 }
3473
3474 /* Remove the data added by previous fragment_add(), and reopen fragments for adding more bytes. */
3475 fragment_truncate(&streaming_reassembly_table, pinfo, reassembly_id, NULL((void*)0), reassembly_info->last_msp->length);
3476 fragment_set_partial_reassembly(&streaming_reassembly_table, pinfo, reassembly_id, NULL((void*)0));
3477
3478 reassembly_info->prev_deseg_len = bytes_belong_to_prev_msp + pinfo->desegment_len;
3479 bytes_belong_to_prev_msp = MIN(reassembly_info->prev_deseg_len, length)(((reassembly_info->prev_deseg_len) < (length)) ? (reassembly_info
->prev_deseg_len) : (length))
;
3480 reassembly_info->prev_deseg_len -= bytes_belong_to_prev_msp;
3481 need_more = (reassembly_info->prev_deseg_len > 0);
3482 continue;
3483 }
3484 }
3485
3486 if (pinfo->desegment_len == 0 || found_BoMSP) {
3487 /* We will arrive here, only when the MSP is defragmented and dissected or this
3488 * payload all belongs to previous MSP (only fragment_add() with need_more=true called)
3489 * or BoMSP is parsed while pinfo->desegment_offset > 0 and pinfo->desegment_len != 0
3490 */
3491 offset += bytes_belong_to_prev_msp;
3492 length -= bytes_belong_to_prev_msp;
3493 DISSECTOR_ASSERT(length >= 0)((void) ((length >= 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3493,
"length >= 0"))))
;
3494 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3495 reassembly_info->last_msp->length += bytes_belong_to_prev_msp;
3496 }
3497
3498 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited) && reassembled_tvb) {
3499 /* completed current msp */
3500 reassembly_info->last_msp->last_frame = cur_frame_num;
3501 reassembly_info->last_msp->end_offset_at_last_frame = offset;
3502 reassembly_info->prev_deseg_len = pinfo->desegment_len;
3503 }
3504 bytes_belong_to_prev_msp = 0; /* break */
3505 }
3506 }
3507
3508 /* to find and handle OmNFP, and find BoMSP at first scan. */
3509 if (length > 0 && !found_BoMSP) {
3510 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3511 /* It is first scan, to dissect remaining bytes to find whether it is OmNFP only, or BoMSP only or OmNFP + BoMSP. */
3512 datalen = length;
3513 DISSECTOR_ASSERT(cur_msp == NULL)((void) ((cur_msp == ((void*)0)) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3513,
"cur_msp == ((void*)0)"))))
;
3514 } else {
3515 /* Not first scan */
3516 if (cur_msp) {
3517 /* There's a BoMSP. Let's calculate the length of OmNFP between EoMSP and BoMSP */
3518 datalen = cur_msp->start_offset_at_first_frame - offset; /* if result is zero that means no OmNFP */
3519 } else {
3520 /* This payload is not a beginning of MSP. The remaining bytes all belong to OmNFP without BoMSP */
3521 datalen = length;
3522 }
3523 }
3524 DISSECTOR_ASSERT(datalen >= 0)((void) ((datalen >= 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3524,
"datalen >= 0"))))
;
3525
3526 /* Dissect the remaining of this payload. If (datalen == 0) means remaining only have one BoMSP without OmNFP. */
3527 if (datalen > 0) {
3528 /* we dissect if it is not dissected before or it is a non-fragment pdu (between two multisegment pdus) */
3529 pinfo->can_desegment = 2;
3530 pinfo->desegment_offset = 0;
3531 pinfo->desegment_len = 0;
3532
3533 call_dissector_only(subdissector_handle, tvb_new_subset_length(tvb, offset, datalen),
3534 pinfo, subdissector_tree, subdissector_data);
3535
3536 if (pinfo->desegment_len) {
3537 DISSECTOR_ASSERT_HINT(pinfo->desegment_len != DESEGMENT_UNTIL_FIN, "Subdissector MUST NOT "((void) ((pinfo->desegment_len != 0x0ffffffe) ? (void)0 : (
proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)"
, "epan/reassemble.c", 3539, "pinfo->desegment_len != 0x0ffffffe"
, "Subdissector MUST NOT " "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to "
" DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined."
))))
3538 "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to "((void) ((pinfo->desegment_len != 0x0ffffffe) ? (void)0 : (
proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)"
, "epan/reassemble.c", 3539, "pinfo->desegment_len != 0x0ffffffe"
, "Subdissector MUST NOT " "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to "
" DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined."
))))
3539 " DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined.")((void) ((pinfo->desegment_len != 0x0ffffffe) ? (void)0 : (
proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)"
, "epan/reassemble.c", 3539, "pinfo->desegment_len != 0x0ffffffe"
, "Subdissector MUST NOT " "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to "
" DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined."
))))
;
3540 /* only happen during first scan */
3541 DISSECTOR_ASSERT(!PINFO_FD_VISITED(pinfo) && datalen == length)((void) ((!((pinfo)->fd->visited) && datalen ==
length) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/reassemble.c", 3541, "!((pinfo)->fd->visited) && datalen == length"
))))
;
3542 offset += pinfo->desegment_offset;
3543 length -= pinfo->desegment_offset;
3544 } else {
3545 /* all remaining bytes are consumed by subdissector */
3546 offset += datalen;
3547 length -= datalen;
3548 }
3549 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3550 reassembly_info->prev_deseg_len = pinfo->desegment_len;
3551 }
3552 } /* else all remaining bytes (BoMSP) belong to a new MSP */
3553 DISSECTOR_ASSERT(length >= 0)((void) ((length >= 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3553,
"length >= 0"))))
;
3554 }
3555
3556 /* handling BoMSP */
3557 if (length > 0) {
3558 col_append_sep_fstr(pinfo->cinfo, COL_INFO, " ", "[%s segment of a reassembled PDU] ", label);
3559 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3560 /* create a msp for current frame during first scan */
3561 cur_msp = wmem_new0(wmem_file_scope(), multisegment_pdu_t)((multisegment_pdu_t*)wmem_alloc0((wmem_file_scope()), sizeof
(multisegment_pdu_t)))
;
3562 cur_msp->first_frame = cur_frame_num;
3563 cur_msp->last_frame = UINT64_MAX(18446744073709551615UL);
3564 cur_msp->start_offset_at_first_frame = offset;
3565 cur_msp->length = length;
3566 cur_msp->streaming_reassembly_id = reassembly_id = create_streaming_reassembly_id();
3567 cur_msp->prev_msp = reassembly_info->last_msp;
3568 reassembly_info->last_msp = cur_msp;
3569 if (reassembly_info->multisegment_pdus == NULL((void*)0)) {
3570 reassembly_info->multisegment_pdus = wmem_map_new(wmem_file_scope(), g_int64_hash, g_int64_equal);
3571 }
3572 frame_ptr = (uint64_t*)wmem_memdup(wmem_file_scope(), &cur_frame_num, sizeof(uint64_t));
3573 wmem_map_insert(reassembly_info->multisegment_pdus, frame_ptr, cur_msp);
3574 } else {
3575 DISSECTOR_ASSERT(cur_msp && cur_msp->start_offset_at_first_frame == offset)((void) ((cur_msp && cur_msp->start_offset_at_first_frame
== offset) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/reassemble.c", 3575, "cur_msp && cur_msp->start_offset_at_first_frame == offset"
))))
;
3576 reassembly_id = cur_msp->streaming_reassembly_id;
3577 }
3578 /* add first fragment of the new MSP to reassembly table */
3579 head = fragment_add(&streaming_reassembly_table, tvb, offset, pinfo, reassembly_id,
3580 NULL((void*)0), 0, length, true1);
3581
3582 if (head && frag_hf_items->hf_reassembled_in) {
3583 proto_item_set_generated(
3584 proto_tree_add_uint(segment_tree, *(frag_hf_items->hf_reassembled_in),
3585 tvb, offset, length, head->reassembled_in)
3586 );
3587 }
3588 proto_tree_add_bytes_format(segment_tree, hf_segment_data, tvb, offset, length,
3589 NULL((void*)0), "%s Segment data (%u byte%s)", label, length, plurality(length, "", "s")((length) == 1 ? ("") : ("s")));
3590 }
3591
3592 pinfo->can_desegment = save_can_desegment;
3593 pinfo->desegment_offset = save_desegment_offset;
3594 pinfo->desegment_len = save_desegment_len;
3595
3596 return orig_length;
3597}
3598
3599int
3600additional_bytes_expected_to_complete_reassembly(streaming_reassembly_info_t* reassembly_info)
3601{
3602 return reassembly_info->prev_deseg_len;
3603}
3604
3605/*
3606 * Editor modelines - https://www.wireshark.org/tools/modelines.html
3607 *
3608 * Local variables:
3609 * c-basic-offset: 8
3610 * tab-width: 8
3611 * indent-tabs-mode: t
3612 * End:
3613 *
3614 * vi: set shiftwidth=8 tabstop=8 noexpandtab:
3615 * :indentSize=8:tabSize=8:noTabs=false:
3616 */