Bug Summary

File:builds/wireshark/wireshark/epan/reassemble.c
Warning:line 1527, 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 REX_API=extern -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/2026-10-31-100332-3661-1 -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) {
10
Assuming the condition is false
11
Taking false branch
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)
12
Assuming 'fd->frame' is <= 'fd_head->frame'
13
Taking false branch
1293 fd_head->frame = fd->frame;
1294
1295 if (!more_frags) {
14
Assuming 'more_frags' is true
15
Taking false branch
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) {
16
Taking false branch
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)) {
17
Assuming the condition is false
18
Taking false branch
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) ){
19
Assuming the condition is false
20
Taking false branch
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) {
21
Assuming field 'contiguous_len' is >= field 'datalen'
22
Taking false branch
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);
23
Memory is allocated
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;
24
Assuming 'old_tvb_data' is null
25
'?' condition is false
1389 if (dfpos
25.1
'dfpos' is 0
) {
26
Taking false branch
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) {
27
Loop condition is false. Execution jumps to the end of the function
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 existing end. */
1477 /* duplicate/retransmission/overlap */
1478 fd_i->flags |= FD_OVERLAP0x0002;
1479 fd_head->flags |= FD_OVERLAP0x0002;
1480
1481 /* How much overlap is there with data in the buffer?
1482 * (It's possible that multiple fragments conflict in
1483 * data past the given datalen; we don't check that.) */
1484 overlap = MIN(dfpos, fd_head->datalen)(((dfpos) < (fd_head->datalen)) ? (dfpos) : (fd_head->
datalen))
- fd_i->offset;
1485 uint32_t cmp_len = MIN(fd_i->len,overlap)(((fd_i->len) < (overlap)) ? (fd_i->len) : (overlap)
)
;
1486
1487 if ( cmp_len && memcmp(data + fd_i->offset,
1488 tvb_get_ptr(fd_i->tvb_data, 0, cmp_len),
1489 cmp_len)
1490 ) {
1491 fd_i->flags |= FD_OVERLAPCONFLICT0x0004;
1492 fd_head->flags |= FD_OVERLAPCONFLICT0x0004;
1493 }
1494 }
1495 /* XXX: As in the fragment_add_seq funcs
1496 * like fragment_defragment_and_free() the
1497 * existing behavior does not overwrite
1498 * overlapping bytes even if there is a
1499 * conflict. It only adds new bytes.
1500 *
1501 * Since we only add fragments to a reassembly
1502 * if the reassembly isn't complete, the most
1503 * common case for overlap conflicts is when
1504 * an earlier reassembly isn't fully contained
1505 * in the capture, and we've reused an
1506 * identification number / wrapped around
1507 * offset sequence numbers much later in the
1508 * capture. In that case, we probably *do*
1509 * want to overwrite conflicting bytes, since
1510 * the earlier fragments didn't form a complete
1511 * reassembly and should be effectively thrown
1512 * out rather than mixed with the new ones?
1513 */
1514 if (fd_i->offset + fraglen > dfpos) {
1515 memcpy(data+dfpos,
1516 tvb_get_ptr(fd_i->tvb_data, overlap, fraglen-overlap),
1517 fraglen-overlap);
1518 dfpos = fd_i->offset + fraglen;
1519 }
1520 }
1521 /* Mark that this fragment as used and clear data. */
1522 fd_i->flags |= FD_DEFRAGMENTED0x0001;
1523 fragment_item_free_tvb(fd_i);
1524 }
1525 }
1526
1527 if (old_tvb_data)
28
Potential leak of memory pointed to by 'data'
1528 tvb_add_to_chain(tvb, old_tvb_data);
1529 /* mark this packet as defragmented.
1530 allows us to skip any trailing fragments */
1531 fd_head->flags |= FD_DEFRAGMENTED0x0001;
1532 fd_head->reassembled_in=pinfo->num;
1533 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
1534
1535 /* we don't throw until here to avoid leaking old_data and others */
1536 if (fd_head->error) {
1537 THROW_MESSAGE(ReassemblyError, fd_head->error)except_throw(1, (9), (fd_head->error));
1538 }
1539
1540 return true1;
1541}
1542
1543static fragment_head *
1544fragment_add_common(reassembly_table *table, tvbuff_t *tvb, const int offset,
1545 const packet_info *pinfo, const uint32_t id,
1546 const void *data, const uint32_t frag_offset,
1547 const uint32_t frag_data_len, const bool_Bool more_frags,
1548 const bool_Bool check_already_added,
1549 const uint32_t frag_frame)
1550{
1551 fragment_head *fd_head;
1552 fragment_item *fd_item;
1553 bool_Bool already_added;
1554
1555
1556 /*
1557 * Dissector shouldn't give us garbage tvb info.
1558 *
1559 * XXX - should this code take responsibility for preventing
1560 * reassembly if data is missing due to the packets being
1561 * sliced, rather than leaving it up to dissectors?
1562 */
1563 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", 1563, "tvb_bytes_exist(tvb, offset, frag_data_len)"
))))
;
1564
1565 fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
1566
1567#if 0
1568 /* debug output of associated fragments. */
1569 /* leave it here for future debugging sessions */
1570 if(strcmp(pinfo->current_proto, "DCERPC") == 0) {
1571 printf("proto:%s num:%u id:%u offset:%u len:%u more:%u visited:%u\n",
1572 pinfo->current_proto, pinfo->num, id, frag_offset, frag_data_len, more_frags, pinfo->fd->visited);
1573 if(fd_head != NULL((void*)0)) {
1574 for(fd_item=fd_head->next;fd_item;fd_item=fd_item->next){
1575 printf("fd_frame:%u fd_offset:%u len:%u datalen:%u\n",
1576 fd_item->frame, fd_item->offset, fd_item->len, fd_item->datalen);
1577 }
1578 }
1579 }
1580#endif
1581
1582 /*
1583 * Is this the first pass through the capture?
1584 */
1585 if (!pinfo->fd->visited) {
1586 /*
1587 * Yes, so we could be doing reassembly. If
1588 * "check_already_added" is true, and fd_head is non-null,
1589 * meaning that this fragment would be added to an
1590 * in-progress reassembly, check if we have seen this
1591 * fragment before, i.e., if we have already added it to
1592 * that reassembly. That can be true even on the first pass
1593 * since we sometimes might call a subdissector multiple
1594 * times.
1595 *
1596 * We check both the frame number and the fragment offset,
1597 * so that we support multiple fragments from the same
1598 * frame being added to the same reassembled PDU.
1599 */
1600 if (check_already_added && fd_head != NULL((void*)0)) {
1601 /*
1602 * fd_head->frame is the maximum of the frame
1603 * numbers of all the fragments added to this
1604 * reassembly; if this frame is later than that
1605 * frame, we know it hasn't been added yet.
1606 */
1607 if (frag_frame <= fd_head->frame) {
1608 already_added = false0;
1609 /*
1610 * The first item in the reassembly list
1611 * is not a fragment, it's a data structure
1612 * for the reassembled packet, so we
1613 * start checking with the next item.
1614 */
1615 for (fd_item = fd_head->next; fd_item;
1616 fd_item = fd_item->next) {
1617 if (frag_frame == fd_item->frame &&
1618 frag_offset == fd_item->offset) {
1619 already_added = true1;
1620 break;
1621 }
1622 }
1623 if (already_added) {
1624 /*
1625 * Have we already finished
1626 * reassembling?
1627 */
1628 if (fd_head->flags & FD_DEFRAGMENTED0x0001) {
1629 /*
1630 * Yes.
1631 * XXX - can this ever happen?
1632 */
1633 THROW_MESSAGE(ReassemblyError,except_throw(1, (9), ("Frame already added in first pass"))
1634 "Frame already added in first pass")except_throw(1, (9), ("Frame already added in first pass"));
1635 } else {
1636 /*
1637 * No.
1638 */
1639 return NULL((void*)0);
1640 }
1641 }
1642 }
1643 }
1644 } else {
1645 /*
1646 * No, so we've already done all the reassembly and added
1647 * all the fragments. Do we have a reassembly and, if so,
1648 * have we finished reassembling?
1649 */
1650 if (fd_head != NULL((void*)0) && fd_head->flags & FD_DEFRAGMENTED0x0001) {
1651 /*
1652 * Yes. This is probably being done after the
1653 * first pass, and we've already done the work
1654 * on the first pass.
1655 *
1656 * If the reassembly got a fatal error, throw that
1657 * error again.
1658 */
1659 if (fd_head->error)
1660 THROW_MESSAGE(ReassemblyError, fd_head->error)except_throw(1, (9), (fd_head->error));
1661
1662 /*
1663 * Is it later in the capture than all of the
1664 * fragments in the reassembly?
1665 */
1666 if (frag_frame > fd_head->frame) {
1667 /*
1668 * Yes, so report this as a problem,
1669 * possibly a retransmission.
1670 */
1671 THROW_MESSAGE(ReassemblyError, "New fragment overlaps old data (retransmission?)")except_throw(1, (9), ("New fragment overlaps old data (retransmission?)"
))
;
1672 }
1673
1674 /*
1675 * Does this fragment go past the end of the
1676 * results of that reassembly?
1677 */
1678 if (frag_offset + frag_data_len > fd_head->datalen) {
1679 /*
1680 * Yes.
1681 */
1682 if (frag_offset >= fd_head->datalen) {
1683 /*
1684 * The fragment starts past the
1685 * end of the reassembled data.
1686 */
1687 THROW_MESSAGE(ReassemblyError, "New fragment past old data limits")except_throw(1, (9), ("New fragment past old data limits"));
1688 } else {
1689 /*
1690 * The fragment starts before the end
1691 * of the reassembled data, but
1692 * runs past the end. That could
1693 * just be a retransmission.
1694 */
1695 THROW_MESSAGE(ReassemblyError, "New fragment overlaps old data (retransmission?)")except_throw(1, (9), ("New fragment overlaps old data (retransmission?)"
))
;
1696 }
1697 }
1698
1699 return fd_head;
1700 } else {
1701 /*
1702 * No.
1703 */
1704 return NULL((void*)0);
1705 }
1706 }
1707
1708 if (fd_head==NULL((void*)0)){
1709 /* not found, this must be the first snooped fragment for this
1710 * packet. Create list-head.
1711 */
1712 fd_head = new_head(0);
1713
1714 /*
1715 * Insert it into the hash table.
1716 */
1717 insert_fd_head(table, fd_head, pinfo, id, data);
1718 }
1719
1720 if (fragment_add_work(fd_head, tvb, offset, pinfo, frag_offset,
1721 frag_data_len, more_frags, frag_frame, false0)) {
1722 /*
1723 * Reassembly is complete.
1724 */
1725 return fd_head;
1726 } else {
1727 /*
1728 * Reassembly isn't complete.
1729 */
1730 return NULL((void*)0);
1731 }
1732}
1733
1734fragment_head *
1735fragment_add(reassembly_table *table, tvbuff_t *tvb, const int offset,
1736 const packet_info *pinfo, const uint32_t id, const void *data,
1737 const uint32_t frag_offset, const uint32_t frag_data_len,
1738 const bool_Bool more_frags)
1739{
1740 return fragment_add_common(table, tvb, offset, pinfo, id, data,
1741 frag_offset, frag_data_len, more_frags, true1, pinfo->num);
1742}
1743
1744/*
1745 * For use when you can have multiple fragments in the same frame added
1746 * to the same reassembled PDU, e.g. with ONC RPC-over-TCP.
1747 */
1748fragment_head *
1749fragment_add_multiple_ok(reassembly_table *table, tvbuff_t *tvb,
1750 const int offset, const packet_info *pinfo,
1751 const uint32_t id, const void *data,
1752 const uint32_t frag_offset,
1753 const uint32_t frag_data_len, const bool_Bool more_frags)
1754{
1755 return fragment_add_common(table, tvb, offset, pinfo, id, data,
1756 frag_offset, frag_data_len, more_frags, false0, pinfo->num);
1757}
1758
1759/*
1760 * For use in protocols like TCP when you are adding an out of order segment
1761 * that arrived in an earlier frame because the correct fragment id could not
1762 * be determined until later. By allowing fd->frame to be different than
1763 * pinfo->num, show_fragment_tree will display the correct fragment numbers.
1764 *
1765 * Note that pinfo is still used to set reassembled_in if we have all the
1766 * fragments, so that results on subsequent passes can be the same as the
1767 * first pass.
1768 */
1769fragment_head *
1770fragment_add_out_of_order(reassembly_table *table, tvbuff_t *tvb,
1771 const int offset, const packet_info *pinfo,
1772 const uint32_t id, const void *data,
1773 const uint32_t frag_offset,
1774 const uint32_t frag_data_len,
1775 const bool_Bool more_frags, const uint32_t frag_frame)
1776{
1777 return fragment_add_common(table, tvb, offset, pinfo, id, data,
1778 frag_offset, frag_data_len, more_frags, true1, frag_frame);
1779}
1780
1781
1782static fragment_head *
1783fragment_add_check_common(reassembly_table *table, tvbuff_t *tvb, const int offset,
1784 const packet_info *pinfo, const uint32_t id,
1785 const void *data, uint32_t frag_offset,
1786 const uint32_t frag_data_len, const bool_Bool more_frags,
1787 const uint32_t flags, const uint32_t fallback_frame)
1788{
1789 reassembled_key reass_key;
1790 fragment_head *fd_head;
1791 void *orig_key;
1792 bool_Bool late_retransmission = false0;
1793
1794 /*
1795 * If this isn't the first pass, look for this frame in the table
1796 * of reassembled packets.
1797 */
1798 if (pinfo->fd->visited) {
2
Assuming field 'visited' is 0
3
Taking false branch
1799 reass_key.frame = pinfo->num;
1800 reass_key.id = id;
1801 return (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
1802 }
1803
1804 /* Looks up a key in the GHashTable, returning the original key and the associated value
1805 * and a bool which is true if the key was found. This is useful if you need to free
1806 * the memory allocated for the original key, for example before calling g_hash_table_remove()
1807 */
1808 fd_head = lookup_fd_head(table, pinfo, id, data, &orig_key);
1809 if ((fd_head == NULL((void*)0)) && (fallback_frame != pinfo->num)) {
4
Assuming 'fd_head' is not equal to NULL
1810 /* Check if there is completed reassembly reachable from fallback frame */
1811 reass_key.frame = fallback_frame;
1812 reass_key.id = id;
1813 fd_head = (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
1814 if (fd_head != NULL((void*)0)) {
1815 /* Found completely reassembled packet, hash it with current frame number */
1816 reassembled_key *new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc ((sizeof (reassembled_key) >
0 ? sizeof (reassembled_key) : 1)))
;
1817 new_key->frame = pinfo->num;
1818 new_key->id = id;
1819 reassembled_table_insert(table->reassembled_table, new_key, fd_head);
1820 late_retransmission = true1;
1821 }
1822 }
1823 if (fd_head
4.1
'fd_head' is not equal to NULL
== NULL((void*)0)) {
5
Taking false branch
1824 /* not found, this must be the first snooped fragment for this
1825 * packet. Create list-head.
1826 */
1827 fd_head = new_head(0);
1828
1829 if((flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001)
1830 && !more_frags) {
1831 /*
1832 * This is the last fragment for this packet, and
1833 * is the only one we've seen.
1834 *
1835 * We assume this is the first and only fragment for
1836 * this packet; just add the head of the list to
1837 * the table of reassembled packets.
1838 */
1839 /* To save memory, we don't actually copy the
1840 * fragment from the tvbuff to the fragment, and in
1841 * process_reassembled_data just return back a subset
1842 * of the original tvbuff (which must be passed in).
1843 */
1844 fd_head->datalen = frag_data_len;
1845 fd_head->reassembled_in=pinfo->num;
1846 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
1847 /*
1848 * Add this item to the table of reassembled packets.
1849 */
1850 fragment_reassembled(table, fd_head, pinfo, id);
1851 return fd_head;
1852 }
1853 /*
1854 * Save the key, for unhashing it later.
1855 */
1856 orig_key = insert_fd_head(table, fd_head, pinfo, id, data);
1857
1858 if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001)
1859 frag_offset = 0;
1860 } else {
1861 if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001) {
6
Taking true branch
1862 /* There are no gaps by construction, so we can
1863 * simply use the contiguous length. */
1864 frag_offset = fd_head->contiguous_len;
1865 }
1866 }
1867
1868 /*
1869 * If this is a short frame, then we can't, and don't, do
1870 * reassembly on it. We just give up.
1871 */
1872 if (!tvb_bytes_exist(tvb, offset, frag_data_len)) {
7
Assuming the condition is false
8
Taking false branch
1873 return NULL((void*)0);
1874 }
1875
1876 if (fragment_add_work(fd_head, tvb, offset, pinfo, frag_offset,
9
Calling 'fragment_add_work'
1877 frag_data_len, more_frags, pinfo->num, late_retransmission)) {
1878 /* Nothing left to do if it was a late retransmission */
1879 if (late_retransmission) {
1880 return fd_head;
1881 }
1882 /*
1883 * Reassembly is complete.
1884 * Remove this from the table of in-progress
1885 * reassemblies, add it to the table of
1886 * reassembled packets, and return it.
1887 */
1888
1889 /*
1890 * Remove this from the table of in-progress reassemblies,
1891 * and free up any memory used for it in that table.
1892 */
1893 fragment_unhash(table, orig_key);
1894
1895 /*
1896 * Add this item to the table of reassembled packets.
1897 */
1898 fragment_reassembled(table, fd_head, pinfo, id);
1899 return fd_head;
1900 } else {
1901 /*
1902 * Reassembly isn't complete.
1903 */
1904 return NULL((void*)0);
1905 }
1906}
1907
1908fragment_head *
1909fragment_add_check_with_fallback(reassembly_table *table, tvbuff_t *tvb, const int offset,
1910 const packet_info *pinfo, const uint32_t id,
1911 const void *data, const uint32_t frag_offset,
1912 const uint32_t frag_data_len, const bool_Bool more_frags,
1913 const uint32_t fallback_frame)
1914{
1915 return fragment_add_check_common(table, tvb, offset, pinfo, id, data,
1916 frag_offset, frag_data_len, more_frags, 0, fallback_frame);
1917}
1918
1919fragment_head *
1920fragment_add_check(reassembly_table *table, tvbuff_t *tvb, const int offset,
1921 const packet_info *pinfo, const uint32_t id,
1922 const void *data, const uint32_t frag_offset,
1923 const uint32_t frag_data_len, const bool_Bool more_frags)
1924{
1925 return fragment_add_check_common(table, tvb, offset, pinfo, id, data,
1926 frag_offset, frag_data_len, more_frags, 0, pinfo->num);
1927}
1928
1929fragment_head *
1930fragment_add_check_next(reassembly_table *table, tvbuff_t *tvb, const int offset,
1931 const packet_info *pinfo, const uint32_t id,
1932 const void *data,
1933 const uint32_t frag_data_len, const bool_Bool more_frags)
1934{
1935 return fragment_add_check_common(table, tvb, offset, pinfo, id, data,
1
Calling 'fragment_add_check_common'
1936 0, frag_data_len, more_frags, REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001, pinfo->num);
1937}
1938
1939static void
1940fragment_defragment_and_free (fragment_head *fd_head, const packet_info *pinfo)
1941{
1942 fragment_item *fd_i = NULL((void*)0);
1943 fragment_item *last_fd = NULL((void*)0);
1944 uint32_t dfpos = 0, old_dfpos = 0, size = 0;
1945 tvbuff_t *old_tvb_data = NULL((void*)0);
1946 uint8_t *data;
1947
1948 for(fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
1949 if(!last_fd || last_fd->offset!=fd_i->offset){
1950 if (ckd_add(&size, size, fd_i->len)__builtin_add_overflow((size), (fd_i->len), (&size)) || size > INT32_MAX(2147483647)) {
1951 /* Change this maximum size when unsigned lengths
1952 * are fully supported (#20103). */
1953 size = INT32_MAX(2147483647);
1954 break;
1955 }
1956 }
1957 last_fd=fd_i;
1958 }
1959
1960 /* store old data in case the fd_i->data pointers refer to it */
1961 old_tvb_data=fd_head->tvb_data;
1962 data = (uint8_t *) g_malloc(size);
1963 fd_head->tvb_data = tvb_new_real_data(data, size, size);
1964 tvb_set_free_cb(fd_head->tvb_data, g_free);
1965 fd_head->len = size; /* record size for caller */
1966
1967 if (old_tvb_data) {
1968 dfpos = tvb_captured_length(old_tvb_data);
1969 memcpy(data, tvb_get_ptr(old_tvb_data, 0, dfpos), MIN(size, dfpos)(((size) < (dfpos)) ? (size) : (dfpos)));
1970 }
1971
1972 /* add all data fragments */
1973 last_fd=NULL((void*)0);
1974 dfpos = 0;
1975 for (fd_i=fd_head->next; fd_i; fd_i=fd_i->next) {
1976 if (fd_i->len) {
1977 if (dfpos >= size) {
1978 fd_i->flags |= FD_TOOLONGFRAGMENT0x0010; // FD_OVERFLOW?
1979 fd_head->flags |= FD_TOOLONGFRAGMENT0x0010; // FD_OVERFLOW?
1980 } else if (!last_fd || last_fd->offset != fd_i->offset) {
1981 /* First fragment or in-sequence fragment */
1982 /* We need the position for overlap calculation of new fragments */
1983 uint32_t copy_len = fd_i->len;
1984 old_dfpos = dfpos;
1985 if (ckd_add(&dfpos, dfpos, fd_i->len)__builtin_add_overflow((dfpos), (fd_i->len), (&dfpos)) || dfpos > size) {
1986 copy_len = size - old_dfpos;
1987 dfpos = size;
1988 fd_i->flags |= FD_TOOLONGFRAGMENT0x0010; // FD_OVERFLOW?
1989 fd_head->flags |= FD_TOOLONGFRAGMENT0x0010; // FD_OVERFLOW?
1990 }
1991 if (!(fd_i->flags & FD_DEFRAGMENTED0x0001)) {
1992 /* Copy if not already copied on the first pass */
1993 memcpy(data + old_dfpos, tvb_get_ptr(fd_i->tvb_data, 0, fd_i->len), copy_len);
1994 }
1995 } else if (!(fd_i->flags & FD_DEFRAGMENTED0x0001)){
1996 /* duplicate/retransmission/overlap */
1997 /* Note that overlaps of old fragments were already calculated. */
1998 fd_i->flags |= FD_OVERLAP0x0002;
1999 fd_head->flags |= FD_OVERLAP0x0002;
2000 if((old_dfpos + fd_i->len != dfpos)
2001 || tvb_memeql(fd_i->tvb_data, 0, data+old_dfpos, fd_i->len) ) {
2002 fd_i->flags |= FD_OVERLAPCONFLICT0x0004;
2003 fd_head->flags |= FD_OVERLAPCONFLICT0x0004;
2004 }
2005 }
2006 fragment_item_free_tvb(fd_i);
2007 fd_i->flags |= FD_DEFRAGMENTED0x0001;
2008 }
2009 last_fd=fd_i;
2010 }
2011
2012 if (old_tvb_data)
2013 tvb_free(old_tvb_data);
2014
2015 /* mark this packet as defragmented.
2016 * allows us to skip any trailing fragments.
2017 */
2018 fd_head->flags |= FD_DEFRAGMENTED0x0001;
2019 fd_head->reassembled_in=pinfo->num;
2020 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
2021}
2022
2023/*
2024 * This function adds a new fragment to the entry for a reassembly
2025 * operation.
2026 *
2027 * The list of fragments for a specific datagram is kept sorted for
2028 * easier handling.
2029 *
2030 * Returns true if we have all the fragments, false otherwise.
2031 *
2032 * This function assumes frag_number being a block sequence number.
2033 * The bsn for the first block is 0.
2034 */
2035static bool_Bool
2036fragment_add_seq_work(fragment_head *fd_head, tvbuff_t *tvb, const int offset,
2037 const packet_info *pinfo, const uint32_t frag_number,
2038 const uint32_t frag_data_len, const bool_Bool more_frags)
2039{
2040 fragment_item *fd;
2041 fragment_item *fd_i;
2042 fragment_item *last_fd;
2043 uint32_t max, dfpos;
2044 uint32_t frag_number_work;
2045
2046 /* Enables the use of fragment sequence numbers, which do not start with 0 */
2047 frag_number_work = frag_number;
2048 if ( fd_head->fragment_nr_offset != 0 )
2049 if ( frag_number_work >= fd_head->fragment_nr_offset )
2050 frag_number_work = frag_number - fd_head->fragment_nr_offset;
2051
2052 /* if the partial reassembly flag has been set, and we are extending
2053 * the pdu, un-reassemble the pdu. This means pointing old fds to malloc'ed data.
2054 */
2055 if(fd_head->flags & FD_DEFRAGMENTED0x0001 && frag_number_work >= fd_head->datalen &&
2056 fd_head->flags & FD_PARTIAL_REASSEMBLY0x0040){
2057
2058 fragment_reset_defragmentation(fd_head);
2059 }
2060
2061
2062 /* create new fd describing this fragment */
2063 fd = new_fragment_item(pinfo->num, frag_number_work, frag_data_len);
2064
2065 /* fd_head->frame is the maximum of the frame numbers of all the
2066 * fragments added to the reassembly. */
2067 if (fd->frame > fd_head->frame)
2068 fd_head->frame = fd->frame;
2069
2070 if (!more_frags) {
2071 /*
2072 * This is the tail fragment in the sequence.
2073 */
2074 if (fd_head->flags&FD_DATALEN_SET0x0400) {
2075 /* ok we have already seen other tails for this packet
2076 * it might be a duplicate.
2077 */
2078 if (fd_head->datalen != fd->offset ){
2079 /* Oops, this tail indicates a different packet
2080 * len than the previous ones. Something's wrong.
2081 */
2082 fd->flags |= FD_MULTIPLETAILS0x0008;
2083 fd_head->flags |= FD_MULTIPLETAILS0x0008;
2084 }
2085 } else {
2086 /* this was the first tail fragment, now we know the
2087 * sequence number of that fragment (which is NOT
2088 * the length of the packet!)
2089 */
2090 fd_head->datalen = fd->offset;
2091 fd_head->flags |= FD_DATALEN_SET0x0400;
2092 }
2093 }
2094
2095 /* If the packet is already defragmented, this MUST be an overlap.
2096 * The entire defragmented packet is in fd_head->data
2097 * Even if we have previously defragmented this packet, we still check
2098 * check it. Someone might play overlap and TTL games.
2099 */
2100 if (fd_head->flags & FD_DEFRAGMENTED0x0001) {
2101 fd->flags |= FD_OVERLAP0x0002|FD_DEFRAGMENTED0x0001;
2102 fd_head->flags |= FD_OVERLAP0x0002;
2103
2104 /* make sure it's not past the end */
2105 if (fd->offset > fd_head->datalen) {
2106 /* new fragment comes after the end */
2107 fd->flags |= FD_TOOLONGFRAGMENT0x0010;
2108 fd_head->flags |= FD_TOOLONGFRAGMENT0x0010;
2109 LINK_FRAG(fd_head,fd);
2110 return true1;
2111 }
2112 /* make sure it doesn't conflict with previous data */
2113 dfpos=0;
2114 last_fd=NULL((void*)0);
2115 for (fd_i=fd_head->next;fd_i && (fd_i->offset!=fd->offset);fd_i=fd_i->next) {
2116 if (!last_fd || last_fd->offset!=fd_i->offset){
2117 dfpos += fd_i->len;
2118 }
2119 last_fd=fd_i;
2120 }
2121 if(fd_i){
2122 /* new fragment overlaps existing fragment */
2123 if(fd_i->len!=fd->len){
2124 /*
2125 * They have different lengths; this
2126 * is definitely a conflict.
2127 */
2128 fd->flags |= FD_OVERLAPCONFLICT0x0004;
2129 fd_head->flags |= FD_OVERLAPCONFLICT0x0004;
2130 LINK_FRAG(fd_head,fd);
2131 return true1;
2132 }
2133 /* Link the fragment first so it is owned by fd_head
2134 * and not leaked if the assertion or the tvb accesses
2135 * below throw an exception. */
2136 LINK_FRAG(fd_head,fd);
2137 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", 2137, "fd_head->len >= dfpos + fd->len"
))))
;
2138 if (tvb_memeql(fd_head->tvb_data, dfpos,
2139 tvb_get_ptr(tvb,offset,fd->len),fd->len) ){
2140 /*
2141 * They have the same length, but the
2142 * data isn't the same.
2143 */
2144 fd->flags |= FD_OVERLAPCONFLICT0x0004;
2145 fd_head->flags |= FD_OVERLAPCONFLICT0x0004;
2146 }
2147 /* otherwise it was just an overlap */
2148 return true1;
2149 } else {
2150 /*
2151 * New fragment doesn't overlap an existing
2152 * fragment - there was presumably a gap in
2153 * the sequence number space.
2154 *
2155 * XXX - what should we do here? Is it always
2156 * the case that there are no gaps, or are there
2157 * protcols using sequence numbers where there
2158 * can be gaps?
2159 *
2160 * If the former, the check below for having
2161 * received all the fragments should check for
2162 * holes in the sequence number space and for the
2163 * first sequence number being 0. If we do that,
2164 * the only way we can get here is if this fragment
2165 * is past the end of the sequence number space -
2166 * but the check for "fd->offset > fd_head->datalen"
2167 * would have caught that above, so it can't happen.
2168 *
2169 * If the latter, we don't have a good way of
2170 * knowing whether reassembly is complete if we
2171 * get packet out of order such that the "last"
2172 * fragment doesn't show up last - but, unless
2173 * in-order reliable delivery of fragments is
2174 * guaranteed, an implementation of the protocol
2175 * has no way of knowing whether reassembly is
2176 * complete, either.
2177 *
2178 * For now, we just link the fragment in and
2179 * return.
2180 */
2181 LINK_FRAG(fd_head,fd);
2182 return true1;
2183 }
2184 }
2185
2186 /* If we have reached this point, the packet is not defragmented yet.
2187 * Save all payload in a buffer until we can defragment.
2188 */
2189 /* check len, there may be a fragment with 0 len, that is actually the tail */
2190 if (fd->len) {
2191 if (!tvb_bytes_exist(tvb, offset, fd->len)) {
2192 /* abort if we didn't capture the entire fragment due
2193 * to a too-short snapshot length */
2194 g_slice_free(fragment_item, fd)do { if (1) g_slice_free1 (sizeof (fragment_item), (fd)); else
(void) ((fragment_item*) 0 == (fd)); } while (0)
;
2195 return false0;
2196 }
2197
2198 fd->tvb_data = tvb_clone_offset_len(tvb, offset, fd->len);
2199 }
2200 LINK_FRAG(fd_head,fd);
2201
2202
2203 if( !(fd_head->flags & FD_DATALEN_SET0x0400) ){
2204 /* if we don't know the sequence number of the last fragment,
2205 * there are definitely still missing packets. Cheaper than
2206 * the check below.
2207 */
2208 return false0;
2209 }
2210
2211
2212 /* check if we have received the entire fragment
2213 * this is easy since the list is sorted and the head is faked.
2214 * common case the whole list is scanned.
2215 */
2216 max = 0;
2217 for(fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
2218 if ( fd_i->offset==max ){
2219 max++;
2220 }
2221 }
2222 /* max will now be datalen+1 if all fragments have been seen */
2223
2224 if (max <= fd_head->datalen) {
2225 /* we have not received all packets yet */
2226 return false0;
2227 }
2228
2229
2230 if (max > (fd_head->datalen+1)) {
2231 /* oops, too long fragment detected */
2232 fd->flags |= FD_TOOLONGFRAGMENT0x0010;
2233 fd_head->flags |= FD_TOOLONGFRAGMENT0x0010;
2234 }
2235
2236
2237 /* we have received an entire packet, defragment it and
2238 * free all fragments
2239 */
2240 fragment_defragment_and_free(fd_head, pinfo);
2241
2242 return true1;
2243}
2244
2245/*
2246 * This function adds a new fragment to the fragment hash table.
2247 * If this is the first fragment seen for this datagram, a new entry
2248 * is created in the hash table, otherwise this fragment is just added
2249 * to the linked list of fragments for this packet.
2250 *
2251 * Returns a pointer to the head of the fragment data list if we have all the
2252 * fragments, NULL otherwise.
2253 *
2254 * This function assumes frag_number being a block sequence number.
2255 * The bsn for the first block is 0.
2256 */
2257static fragment_head *
2258fragment_add_seq_common(reassembly_table *table, tvbuff_t *tvb,
2259 const int offset, const packet_info *pinfo,
2260 const uint32_t id, const void *data,
2261 uint32_t frag_number, const uint32_t frag_data_len,
2262 const bool_Bool more_frags, const uint32_t flags,
2263 void * *orig_keyp)
2264{
2265 fragment_head *fd_head;
2266 void *orig_key;
2267
2268 fd_head = lookup_fd_head(table, pinfo, id, data, &orig_key);
2269
2270 /* have we already seen this frame ?*/
2271 if (pinfo->fd->visited) {
2272 if (fd_head != NULL((void*)0) && fd_head->flags & FD_DEFRAGMENTED0x0001) {
2273 if (orig_keyp != NULL((void*)0))
2274 *orig_keyp = orig_key;
2275 return fd_head;
2276 } else {
2277 return NULL((void*)0);
2278 }
2279 }
2280
2281 if (fd_head==NULL((void*)0)){
2282 /* not found, this must be the first snooped fragment for this
2283 * packet. Create list-head.
2284 */
2285 fd_head = new_head(FD_BLOCKSEQUENCE0x0100);
2286
2287 if((flags & (REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001|REASSEMBLE_FLAGS_802_11_HACK0x0002))
2288 && !more_frags) {
2289 /*
2290 * This is the last fragment for this packet, and
2291 * is the only one we've seen.
2292 *
2293 * Either we don't have sequence numbers, in which
2294 * case we assume this is the first fragment for
2295 * this packet, or we're doing special 802.11
2296 * processing, in which case we assume it's one
2297 * of those reassembled packets with a non-zero
2298 * fragment number (see packet-80211.c); just
2299 * return a pointer to the head of the list;
2300 * fragment_add_seq_check will then add it to the table
2301 * of reassembled packets.
2302 */
2303 if (orig_keyp != NULL((void*)0))
2304 *orig_keyp = NULL((void*)0);
2305 /* To save memory, we don't actually copy the
2306 * fragment from the tvbuff to the fragment, and in
2307 * process_reassembled_data just return back a subset
2308 * of the original tvbuff (which must be passed in).
2309 */
2310 fd_head->len = frag_data_len;
2311 fd_head->reassembled_in=pinfo->num;
2312 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
2313 return fd_head;
2314 }
2315
2316 orig_key = insert_fd_head(table, fd_head, pinfo, id, data);
2317 if (orig_keyp != NULL((void*)0))
2318 *orig_keyp = orig_key;
2319
2320 /*
2321 * If we weren't given an initial fragment number,
2322 * make it 0.
2323 */
2324 if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001)
2325 frag_number = 0;
2326 } else {
2327 if (orig_keyp != NULL((void*)0))
2328 *orig_keyp = orig_key;
2329
2330 /*
2331 * XXX If fd_head exists, but nothing has been added to it,
2332 * i.e. it was created with a known datalen with
2333 * fragment_start_seq_check, we should also be able to
2334 * do the memory saving trick as in the case above
2335 * when first creating it.
2336 */
2337 if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001) {
2338 fragment_item *fd;
2339 /*
2340 * If we weren't given an initial fragment number,
2341 * use the next expected fragment number as the fragment
2342 * number for this fragment.
2343 *
2344 * XXX - Use fd_head->first_gap to speed this up?
2345 */
2346 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next) {
2347 if (fd->next == NULL((void*)0))
2348 frag_number = fd->offset + 1;
2349 }
2350 }
2351 }
2352
2353 if (fragment_add_seq_work(fd_head, tvb, offset, pinfo,
2354 frag_number, frag_data_len, more_frags)) {
2355 /*
2356 * Reassembly is complete.
2357 */
2358 return fd_head;
2359 } else {
2360 /*
2361 * Reassembly isn't complete.
2362 */
2363 return NULL((void*)0);
2364 }
2365}
2366
2367fragment_head *
2368fragment_add_seq(reassembly_table *table, tvbuff_t *tvb, const int offset,
2369 const packet_info *pinfo, const uint32_t id, const void *data,
2370 const uint32_t frag_number, const uint32_t frag_data_len,
2371 const bool_Bool more_frags, const uint32_t flags)
2372{
2373 return fragment_add_seq_common(table, tvb, offset, pinfo, id, data,
2374 frag_number, frag_data_len,
2375 more_frags, flags, NULL((void*)0));
2376}
2377
2378/*
2379 * This does the work for "fragment_add_seq_check()" and
2380 * "fragment_add_seq_next()".
2381 *
2382 * This function assumes frag_number being a block sequence number.
2383 * The bsn for the first block is 0.
2384 *
2385 * If REASSEMBLE_FLAGS_NO_FRAG_NUMBER, it uses the next expected fragment number
2386 * as the fragment number if there is a reassembly in progress, otherwise
2387 * it uses 0.
2388 *
2389 * If not REASSEMBLE_FLAGS_NO_FRAG_NUMBER, it uses the "frag_number" argument as
2390 * the fragment number.
2391 *
2392 * If this is the first fragment seen for this datagram, a new
2393 * "fragment_head" structure is allocated to refer to the reassembled
2394 * packet.
2395 *
2396 * This fragment is added to the linked list of fragments for this packet.
2397 *
2398 * If "more_frags" is false and REASSEMBLE_FLAGS_802_11_HACK (as the name
2399 * implies, a special hack for 802.11) or REASSEMBLE_FLAGS_NO_FRAG_NUMBER
2400 * (implying messages must be in order since there's no sequence number) are
2401 * set in "flags", then this (one element) list is returned.
2402 *
2403 * If, after processing this fragment, we have all the fragments,
2404 * "fragment_add_seq_check_work()" removes that from the fragment hash
2405 * table if necessary and adds it to the table of reassembled fragments,
2406 * and returns a pointer to the head of the fragment list.
2407 *
2408 * Otherwise, it returns NULL.
2409 *
2410 * XXX - Should we simply return NULL for zero-length fragments?
2411 */
2412static fragment_head *
2413fragment_add_seq_check_work(reassembly_table *table, tvbuff_t *tvb,
2414 const int offset, const packet_info *pinfo,
2415 const uint32_t id, const void *data,
2416 const uint32_t frag_number,
2417 const uint32_t frag_data_len,
2418 const bool_Bool more_frags, const uint32_t flags)
2419{
2420 reassembled_key reass_key;
2421 fragment_head *fd_head;
2422 void *orig_key;
2423
2424 /*
2425 * Have we already seen this frame?
2426 * If so, look for it in the table of reassembled packets.
2427 */
2428 if (pinfo->fd->visited) {
2429 reass_key.frame = pinfo->num;
2430 reass_key.id = id;
2431 return (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
2432 }
2433
2434 fd_head = fragment_add_seq_common(table, tvb, offset, pinfo, id, data,
2435 frag_number, frag_data_len,
2436 more_frags,
2437 flags,
2438 &orig_key);
2439 if (fd_head) {
2440 /*
2441 * Reassembly is complete.
2442 *
2443 * If this is in the table of in-progress reassemblies,
2444 * remove it from that table. (It could be that this
2445 * was the first and last fragment, so that no
2446 * reassembly was done.)
2447 */
2448 if (orig_key != NULL((void*)0))
2449 fragment_unhash(table, orig_key);
2450
2451 /*
2452 * Add this item to the table of reassembled packets.
2453 */
2454 fragment_reassembled(table, fd_head, pinfo, id);
2455 return fd_head;
2456 } else {
2457 /*
2458 * Reassembly isn't complete.
2459 */
2460 return NULL((void*)0);
2461 }
2462}
2463
2464fragment_head *
2465fragment_add_seq_check(reassembly_table *table, tvbuff_t *tvb, const int offset,
2466 const packet_info *pinfo, const uint32_t id,
2467 const void *data,
2468 const uint32_t frag_number, const uint32_t frag_data_len,
2469 const bool_Bool more_frags)
2470{
2471 return fragment_add_seq_check_work(table, tvb, offset, pinfo, id, data,
2472 frag_number, frag_data_len,
2473 more_frags, 0);
2474}
2475
2476fragment_head *
2477fragment_add_seq_802_11(reassembly_table *table, tvbuff_t *tvb,
2478 const int offset, const packet_info *pinfo,
2479 const uint32_t id, const void *data,
2480 const uint32_t frag_number, const uint32_t frag_data_len,
2481 const bool_Bool more_frags)
2482{
2483 return fragment_add_seq_check_work(table, tvb, offset, pinfo, id, data,
2484 frag_number, frag_data_len,
2485 more_frags,
2486 REASSEMBLE_FLAGS_802_11_HACK0x0002);
2487}
2488
2489fragment_head *
2490fragment_add_seq_next(reassembly_table *table, tvbuff_t *tvb, const int offset,
2491 const packet_info *pinfo, const uint32_t id,
2492 const void *data, const uint32_t frag_data_len,
2493 const bool_Bool more_frags)
2494{
2495 /* Use a dummy frag_number (0), it is ignored since
2496 * REASSEMBLE_FLAGS_NO_FRAG_NUMBER is set. */
2497 return fragment_add_seq_check_work(table, tvb, offset, pinfo, id, data,
2498 0, frag_data_len, more_frags,
2499 REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001);
2500}
2501
2502static void
2503fragment_add_seq_single_move(reassembly_table *table, const packet_info *pinfo,
2504 const uint32_t id, const void *data,
2505 const uint32_t offset)
2506{
2507 fragment_head *fh, *new_fh;
2508 fragment_item *fd, *prev_fd;
2509 tvbuff_t *old_tvb_data;
2510 if (offset == 0) {
2511 return;
2512 }
2513 fh = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
2514 if (fh == NULL((void*)0)) {
2515 /* Shouldn't be called this way.
2516 * Probably wouldn't hurt to just create fh in this case. */
2517 ws_assert_not_reached()ws_log_fatal_full("", LOG_LEVEL_ERROR, "epan/reassemble.c", 2517
, __func__, "assertion \"not reached\" failed")
;
2518 return;
2519 }
2520 if (fh->flags & FD_DATALEN_SET0x0400 && fh->datalen <= offset) {
2521 /* Don't take from past the end. <= because we don't
2522 * want to take a First fragment from the next one
2523 * either */
2524 return;
2525 }
2526 new_fh = lookup_fd_head(table, pinfo, id+offset, data, NULL((void*)0));
2527 if (new_fh != NULL((void*)0)) {
2528 /* Attach to the end of the sorted list. */
2529 prev_fd = NULL((void*)0);
2530 for(fd = fh->next; fd != NULL((void*)0); fd=fd->next) {
2531 prev_fd = fd;
2532 }
2533 /* Don't take a reassembly starting with a First fragment. */
2534 fd = new_fh->next;
2535 if (fd && fd->offset != 0) {
2536 fragment_item *inserted = fd;
2537 bool_Bool multi_insert = (inserted->next != NULL((void*)0));
2538 if (prev_fd) {
2539 prev_fd->next = fd;
2540 } else {
2541 fh->next = fd;
2542 }
2543 for (; fd; fd=fd->next) {
2544 fd->offset += offset;
2545 if (fh->frame < fd->frame) {
2546 fh->frame = fd->frame;
2547 }
2548 }
2549 update_first_gap(fh, inserted, multi_insert);
2550 /* If previously found a Last fragment,
2551 * transfer that info to the new one. */
2552 if (new_fh->flags & FD_DATALEN_SET0x0400) {
2553 fh->flags |= FD_DATALEN_SET0x0400;
2554 fh->datalen = new_fh->datalen + offset;
2555 }
2556 /* Now remove and delete */
2557 new_fh->next = NULL((void*)0);
2558 old_tvb_data = fragment_delete(table, pinfo, id+offset, data);
2559 if (old_tvb_data)
2560 tvb_free(old_tvb_data);
2561 }
2562 }
2563}
2564
2565static fragment_head *
2566fragment_add_seq_single_work(reassembly_table *table, tvbuff_t *tvb,
2567 const int offset, const packet_info *pinfo,
2568 const uint32_t id, const void* data,
2569 const uint32_t frag_data_len,
2570 const bool_Bool first, const bool_Bool last,
2571 const uint32_t max_frags, const uint32_t max_age,
2572 const uint32_t flags)
2573{
2574 reassembled_key reass_key;
2575 tvbuff_t *old_tvb_data;
2576 void *orig_key;
2577 fragment_head *fh, *new_fh;
2578 fragment_item *fd, *prev_fd;
2579 uint32_t frag_number, tmp_offset;
2580 /* Have we already seen this frame?
2581 * If so, look for it in the table of reassembled packets.
2582 * Note here we store in the reassembly table by the single sequence
2583 * number rather than the sequence number of the First fragment. */
2584 if (pinfo->fd->visited) {
2585 reass_key.frame = pinfo->num;
2586 reass_key.id = id;
2587 fh = (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
2588 return fh;
2589 }
2590 /* First let's figure out where we want to add our new fragment */
2591 fh = NULL((void*)0);
2592 if (first) {
2593 frag_number = 0;
2594 fh = lookup_fd_head(table, pinfo, id-frag_number, data, NULL((void*)0));
2595 if ((flags & REASSEMBLE_FLAGS_AGING0x0001) &&
2596 fh && ((fh->frame + max_age) < pinfo->num)) {
2597 old_tvb_data = fragment_delete(table, pinfo, id-frag_number, data);
2598 if (old_tvb_data)
2599 tvb_free(old_tvb_data);
2600 fh = NULL((void*)0);
2601 }
2602 if (fh == NULL((void*)0)) {
2603 /* Not found. Create list-head. */
2604 fh = new_head(FD_BLOCKSEQUENCE0x0100);
2605 insert_fd_head(table, fh, pinfo, id-frag_number, data);
2606 }
2607 /* As this is the first fragment, we might have added segments
2608 * for this reassembly to the previous one in-progress. */
2609 fd = NULL((void*)0);
2610 for (frag_number=1; frag_number < max_frags; frag_number++) {
2611 new_fh = lookup_fd_head(table, pinfo, id-frag_number, data, NULL((void*)0));
2612 if (new_fh != NULL((void*)0)) {
2613 prev_fd = NULL((void*)0);
2614 new_fh->frame = 0;
2615 for (fd=new_fh->next; fd && fd->offset < frag_number; fd=fd->next) {
2616 prev_fd = fd;
2617 if (new_fh->frame < fd->frame) {
2618 new_fh->frame = fd->frame;
2619 }
2620 }
2621 if (prev_fd) {
2622 prev_fd->next = NULL((void*)0);
2623 } else {
2624 new_fh->next = NULL((void*)0);
2625 }
2626 fragment_items_removed(new_fh, prev_fd);
2627 break;
2628 }
2629 }
2630 if (fd != NULL((void*)0)) {
2631 tmp_offset = 0;
2632 for (prev_fd = fd; prev_fd; prev_fd = prev_fd->next) {
2633 prev_fd->offset -= frag_number;
2634 tmp_offset = prev_fd->offset;
2635 if (fh->frame < prev_fd->frame) {
2636 fh->frame = prev_fd->frame;
2637 }
2638 }
2639 MERGE_FRAG(fh, fd);
2640 if (new_fh != NULL((void*)0)) {
2641 /* If we've moved a Last packet, change datalen.
2642 * Second part of this test prob. redundant? */
2643 if (new_fh->flags & FD_DATALEN_SET0x0400 &&
2644 new_fh->datalen >= frag_number) {
2645 fh->flags |= FD_DATALEN_SET0x0400;
2646 fh->datalen = new_fh->datalen - frag_number;
2647 new_fh->flags &= ~FD_DATALEN_SET0x0400;
2648 new_fh->datalen = 0;
2649 }
2650 /* If we've moved all the fragments,
2651 * delete the old head */
2652 if (new_fh->next == NULL((void*)0)) {
2653 old_tvb_data = fragment_delete(table, pinfo, id-frag_number, data);
2654 if (old_tvb_data)
2655 tvb_free(old_tvb_data);
2656 }
2657 } else {
2658 /* Look forward and take off the next (this is
2659 * necessary in some edge cases where max_frags
2660 * prevented some fragments from going on the
2661 * previous First, but they can go on this one. */
2662 fragment_add_seq_single_move(table, pinfo, id,
2663 data, tmp_offset);
2664 }
2665 }
2666 frag_number = 0; /* For the rest of the function */
2667 } else {
2668 for (frag_number=1; frag_number < max_frags; frag_number++) {
2669 fh = lookup_fd_head(table, pinfo, id-frag_number, data, NULL((void*)0));
2670 if ((flags & REASSEMBLE_FLAGS_AGING0x0001) &&
2671 fh && ((fh->frame + max_age) < pinfo->num)) {
2672 old_tvb_data = fragment_delete(table, pinfo, id-frag_number, data);
2673 if (old_tvb_data)
2674 tvb_free(old_tvb_data);
2675 fh = NULL((void*)0);
2676 }
2677 if (fh != NULL((void*)0)) {
2678 if (fh->flags & FD_DATALEN_SET0x0400 &&
2679 fh->datalen < frag_number) {
2680 /* This fragment is after the Last
2681 * fragment, so must go after here. */
2682 fh = NULL((void*)0);
2683 }
2684 break;
2685 }
2686 }
2687 if (fh == NULL((void*)0)) { /* Didn't find location, use default */
2688 frag_number = 1;
2689 /* Already looked for frag_number 1, so just create */
2690 fh = new_head(FD_BLOCKSEQUENCE0x0100);
2691 insert_fd_head(table, fh, pinfo, id-frag_number, data);
2692 }
2693 }
2694 if (last) {
2695 /* Look for fragments past the end set by this Last fragment. */
2696 prev_fd = NULL((void*)0);
2697 for (fd=fh->next; fd && fd->offset <= frag_number; fd=fd->next) {
2698 prev_fd = fd;
2699 }
2700 /* fd is now all fragments offset > frag_number (the Last).
2701 * It shouldn't have a fragment with offset frag_number+1,
2702 * as that would be a First fragment not marked as such.
2703 * However, this can happen if we had unreassembled fragments
2704 * (missing, or at the start of the capture) and we've also
2705 * looped around on the sequence numbers. It can also happen
2706 * if bit errors mess up Last or First. */
2707 if (fd != NULL((void*)0)) {
2708 if (prev_fd) {
2709 prev_fd->next = NULL((void*)0);
2710 } else {
2711 fh->next = NULL((void*)0);
2712 }
2713 fragment_items_removed(fh, prev_fd);
2714 fh->frame = 0;
2715 for (prev_fd=fh->next; prev_fd; prev_fd=prev_fd->next) {
2716 if (fh->frame < prev_fd->frame) {
2717 fh->frame = prev_fd->frame;
2718 }
2719 }
2720 while (fd && fd->offset == frag_number+1) {
2721 /* Definitely have bad data here. Best to
2722 * delete these and leave unreassembled. */
2723 fd = fragment_item_free(fd);
2724 }
2725 }
2726 if (fd != NULL((void*)0)) {
2727 /* Move these onto the next frame. */
2728 new_fh = lookup_fd_head(table, pinfo, id+1, data, NULL((void*)0));
2729 if (new_fh==NULL((void*)0)) {
2730 /* Not found. Create list-head. */
2731 new_fh = new_head(FD_BLOCKSEQUENCE0x0100);
2732 insert_fd_head(table, new_fh, pinfo, id+1, data);
2733 }
2734 tmp_offset = 0;
2735 for (prev_fd = fd; prev_fd; prev_fd = prev_fd->next) {
2736 prev_fd->offset -= (frag_number+1);
2737 tmp_offset = prev_fd->offset;
2738 if (new_fh->frame < fd->frame) {
2739 new_fh->frame = fd->frame;
2740 }
2741 }
2742 MERGE_FRAG(new_fh, fd);
2743 /* If we previously found a different Last fragment,
2744 * transfer that information to the new reassembly. */
2745 if (fh->flags & FD_DATALEN_SET0x0400 &&
2746 fh->datalen > frag_number) {
2747 new_fh->flags |= FD_DATALEN_SET0x0400;
2748 new_fh->datalen = fh->datalen - (frag_number+1);
2749 fh->flags &= ~FD_DATALEN_SET0x0400;
2750 fh->datalen = 0;
2751 } else {
2752 /* Look forward and take off the next (this is
2753 * necessary in some edge cases where max_frags
2754 * prevented some fragments from going on the
2755 * previous First, but they can go on this one. */
2756 fragment_add_seq_single_move(table, pinfo, id+1,
2757 data, tmp_offset);
2758 }
2759 }
2760 } else {
2761 fragment_add_seq_single_move(table, pinfo, id-frag_number, data,
2762 frag_number+1);
2763 }
2764 /* Having cleaned up everything, finally ready to add our new
2765 * fragment. Note that only this will ever complete a reassembly. */
2766 fh = fragment_add_seq_common(table, tvb, offset, pinfo,
2767 id-frag_number, data,
2768 frag_number, frag_data_len,
2769 !last, 0, &orig_key);
2770 if (fh) {
2771 /*
2772 * Reassembly is complete.
2773 *
2774 * If this is in the table of in-progress reassemblies,
2775 * remove it from that table. (It could be that this
2776 * was the first and last fragment, so that no
2777 * reassembly was done.)
2778 */
2779 if (orig_key != NULL((void*)0))
2780 fragment_unhash(table, orig_key);
2781
2782 /*
2783 * Add this item to the table of reassembled packets.
2784 */
2785 fragment_reassembled_single(table, fh, pinfo, id-frag_number);
2786 return fh;
2787 } else {
2788 /*
2789 * Reassembly isn't complete.
2790 */
2791 return NULL((void*)0);
2792 }
2793}
2794
2795fragment_head *
2796fragment_add_seq_single(reassembly_table *table, tvbuff_t *tvb,
2797 const int offset, const packet_info *pinfo,
2798 const uint32_t id, const void* data,
2799 const uint32_t frag_data_len,
2800 const bool_Bool first, const bool_Bool last,
2801 const uint32_t max_frags)
2802{
2803 return fragment_add_seq_single_work(table, tvb, offset, pinfo,
2804 id, data, frag_data_len,
2805 first, last, max_frags, 0, 0);
2806}
2807
2808fragment_head *
2809fragment_add_seq_single_aging(reassembly_table *table, tvbuff_t *tvb,
2810 const int offset, const packet_info *pinfo,
2811 const uint32_t id, const void* data,
2812 const uint32_t frag_data_len,
2813 const bool_Bool first, const bool_Bool last,
2814 const uint32_t max_frags, const uint32_t max_age)
2815{
2816 return fragment_add_seq_single_work(table, tvb, offset, pinfo,
2817 id, data, frag_data_len,
2818 first, last, max_frags, max_age,
2819 REASSEMBLE_FLAGS_AGING0x0001);
2820}
2821
2822void
2823fragment_start_seq_check(reassembly_table *table, const packet_info *pinfo,
2824 const uint32_t id, const void *data,
2825 const uint32_t tot_len)
2826{
2827 fragment_head *fd_head;
2828
2829 /* Have we already seen this frame ?*/
2830 if (pinfo->fd->visited) {
2831 return;
2832 }
2833
2834 /* Check if fragment data exists */
2835 fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
2836
2837 if (fd_head == NULL((void*)0)) {
2838 /* Create list-head. */
2839 fd_head = new_head(FD_BLOCKSEQUENCE0x0100|FD_DATALEN_SET0x0400);
2840 fd_head->datalen = tot_len;
2841
2842 insert_fd_head(table, fd_head, pinfo, id, data);
2843 }
2844}
2845
2846fragment_head *
2847fragment_end_seq_next(reassembly_table *table, const packet_info *pinfo,
2848 const uint32_t id, const void *data)
2849{
2850 reassembled_key reass_key;
2851 reassembled_key *new_key;
2852 fragment_head *fd_head;
2853 fragment_item *fd;
2854 void *orig_key;
2855 uint32_t max_offset = 0;
2856
2857 /*
2858 * Have we already seen this frame?
2859 * If so, look for it in the table of reassembled packets.
2860 */
2861 if (pinfo->fd->visited) {
2862 reass_key.frame = pinfo->num;
2863 reass_key.id = id;
2864 return (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
2865 }
2866
2867 fd_head = lookup_fd_head(table, pinfo, id, data, &orig_key);
2868
2869 if (fd_head) {
2870 for (fd = fd_head->next; fd; fd = fd->next) {
2871 if (fd->offset > max_offset) {
2872 max_offset = fd->offset;
2873 }
2874 }
2875 fd_head->datalen = max_offset;
2876 fd_head->flags |= FD_DATALEN_SET0x0400;
2877
2878 fragment_defragment_and_free (fd_head, pinfo);
2879
2880 /*
2881 * Remove this from the table of in-progress reassemblies,
2882 * and free up any memory used for it in that table.
2883 */
2884 fragment_unhash(table, orig_key);
2885
2886 /*
2887 * Add this item to the table of reassembled packets.
2888 */
2889 fragment_reassembled(table, fd_head, pinfo, id);
2890 if (fd_head->next != NULL((void*)0)) {
2891 new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc ((sizeof (reassembled_key) >
0 ? sizeof (reassembled_key) : 1)))
;
2892 new_key->frame = pinfo->num;
2893 new_key->id = id;
2894 reassembled_table_insert(table->reassembled_table, new_key, fd_head);
2895 }
2896
2897 return fd_head;
2898 } else {
2899 /*
2900 * Fragment data not found.
2901 */
2902 return NULL((void*)0);
2903 }
2904}
2905
2906/*
2907 * Process reassembled data; if we're on the frame in which the data
2908 * was reassembled, put the fragment information into the protocol
2909 * tree, and construct a tvbuff with the reassembled data, otherwise
2910 * just put a "reassembled in" item into the protocol tree.
2911 * offset from start of tvb, result up to end of tvb
2912 */
2913tvbuff_t *
2914process_reassembled_data(tvbuff_t *tvb, const int offset, packet_info *pinfo,
2915 const char *name, fragment_head *fd_head, const fragment_items *fit,
2916 bool_Bool *update_col_infop, proto_tree *tree)
2917{
2918 tvbuff_t *next_tvb;
2919 bool_Bool update_col_info;
2920 proto_item *frag_tree_item;
2921
2922 if (fd_head != NULL((void*)0) && pinfo->num == fd_head->reassembled_in && pinfo->curr_layer_num == fd_head->reas_in_layer_num) {
2923 /*
2924 * OK, we've reassembled this.
2925 * Is this something that's been reassembled from more
2926 * than one fragment?
2927 */
2928 if (fd_head->next != NULL((void*)0)) {
2929 /*
2930 * Yes.
2931 * Allocate a new tvbuff, referring to the
2932 * reassembled payload, and set
2933 * the tvbuff to the list of tvbuffs to which
2934 * the tvbuff we were handed refers, so it'll get
2935 * cleaned up when that tvbuff is cleaned up.
2936 */
2937 next_tvb = tvb_new_chain(tvb, fd_head->tvb_data);
2938
2939 /* Add the defragmented data to the data source list. */
2940 add_new_data_source(pinfo, next_tvb, name);
2941
2942 /* show all fragments */
2943 if (fd_head->flags & FD_BLOCKSEQUENCE0x0100) {
2944 update_col_info = !show_fragment_seq_tree(
2945 fd_head, fit, tree, pinfo, next_tvb, &frag_tree_item);
2946 } else {
2947 update_col_info = !show_fragment_tree(fd_head,
2948 fit, tree, pinfo, next_tvb, &frag_tree_item);
2949 }
2950 } else {
2951 /*
2952 * No.
2953 * Return a tvbuff with the payload, a subset of the
2954 * tvbuff passed in. (The dissector SHOULD pass in
2955 * the correct tvbuff and offset.)
2956 */
2957 int len;
2958 /* For FD_BLOCKSEQUENCE, len is the length in bytes,
2959 * datalen is the number of fragments.
2960 */
2961 if (fd_head->flags & FD_BLOCKSEQUENCE0x0100) {
2962 len = fd_head->len;
2963 } else {
2964 len = fd_head->datalen;
2965 }
2966 next_tvb = tvb_new_subset_length(tvb, offset, len);
2967 pinfo->fragmented = false0; /* one-fragment packet */
2968 update_col_info = true1;
2969 }
2970 if (update_col_infop != NULL((void*)0))
2971 *update_col_infop = update_col_info;
2972 } else {
2973 /*
2974 * We don't have the complete reassembled payload, or this
2975 * isn't the final frame of that payload.
2976 */
2977 next_tvb = NULL((void*)0);
2978
2979 /*
2980 * If we know what frame this was reassembled in,
2981 * and if there's a field to use for the number of
2982 * the frame in which the packet was reassembled,
2983 * add it to the protocol tree.
2984 */
2985 if (fd_head != NULL((void*)0) && fit->hf_reassembled_in != NULL((void*)0)) {
2986 proto_item *fei = proto_tree_add_uint(tree,
2987 *(fit->hf_reassembled_in), tvb,
2988 0, 0, fd_head->reassembled_in);
2989 proto_item_set_generated(fei);
2990 }
2991 }
2992 return next_tvb;
2993}
2994
2995/*
2996 * Show a single fragment in a fragment subtree, and put information about
2997 * it in the top-level item for that subtree.
2998 */
2999static void
3000show_fragment(fragment_item *fd, const int offset, const fragment_items *fit,
3001 proto_tree *ft, proto_item *fi, const bool_Bool first_frag,
3002 const uint32_t count, tvbuff_t *tvb, packet_info *pinfo)
3003{
3004 proto_item *fei=NULL((void*)0);
3005 int hf;
3006
3007 if (first_frag) {
3008 char *name;
3009 if (count == 1) {
3010 name = g_strdup(proto_registrar_get_name(*(fit->hf_fragment)))g_strdup_inline (proto_registrar_get_name(*(fit->hf_fragment
)))
;
3011 } else {
3012 name = g_strdup(proto_registrar_get_name(*(fit->hf_fragments)))g_strdup_inline (proto_registrar_get_name(*(fit->hf_fragments
)))
;
3013 }
3014 proto_item_set_text(fi, "%u %s (%u byte%s): ", count, name, tvb_captured_length(tvb),
3015 plurality(tvb_captured_length(tvb), "", "s")((tvb_captured_length(tvb)) == 1 ? ("") : ("s")));
3016 g_free(name)(__builtin_object_size ((name), 0) != ((size_t) - 1)) ? g_free_sized
(name, __builtin_object_size ((name), 0)) : (g_free) (name)
;
3017 } else {
3018 proto_item_append_text(fi, ", ");
3019 }
3020 proto_item_append_text(fi, "#%u(%u)", fd->frame, fd->len);
3021
3022 if (fd->flags & (FD_OVERLAPCONFLICT0x0004
3023 |FD_MULTIPLETAILS0x0008|FD_TOOLONGFRAGMENT0x0010) ) {
3024 hf = *(fit->hf_fragment_error);
3025 } else {
3026 hf = *(fit->hf_fragment);
3027 }
3028 if (fd->len == 0) {
3029 fei = proto_tree_add_uint_format(ft, hf,
3030 tvb, offset, fd->len,
3031 fd->frame,
3032 "Frame: %u (no data)",
3033 fd->frame);
3034 } else {
3035 fei = proto_tree_add_uint_format(ft, hf,
3036 tvb, offset, fd->len,
3037 fd->frame,
3038 "Frame: %u, payload: %u-%u (%u byte%s)",
3039 fd->frame,
3040 offset,
3041 offset+fd->len-1,
3042 fd->len,
3043 plurality(fd->len, "", "s")((fd->len) == 1 ? ("") : ("s")));
3044 }
3045 proto_item_set_generated(fei);
3046 mark_frame_as_depended_upon(pinfo->fd, fd->frame);
3047 if (fd->flags & (FD_OVERLAP0x0002|FD_OVERLAPCONFLICT0x0004
3048 |FD_MULTIPLETAILS0x0008|FD_TOOLONGFRAGMENT0x0010) ) {
3049 /* this fragment has some flags set, create a subtree
3050 * for it and display the flags.
3051 */
3052 proto_tree *fet=NULL((void*)0);
3053
3054 fet = proto_item_add_subtree(fei, *(fit->ett_fragment));
3055 if (fd->flags&FD_OVERLAP0x0002) {
3056 fei=proto_tree_add_boolean(fet,
3057 *(fit->hf_fragment_overlap),
3058 tvb, 0, 0,
3059 true1);
3060 proto_item_set_generated(fei);
3061 }
3062 if (fd->flags&FD_OVERLAPCONFLICT0x0004) {
3063 fei=proto_tree_add_boolean(fet,
3064 *(fit->hf_fragment_overlap_conflict),
3065 tvb, 0, 0,
3066 true1);
3067 proto_item_set_generated(fei);
3068 }
3069 if (fd->flags&FD_MULTIPLETAILS0x0008) {
3070 fei=proto_tree_add_boolean(fet,
3071 *(fit->hf_fragment_multiple_tails),
3072 tvb, 0, 0,
3073 true1);
3074 proto_item_set_generated(fei);
3075 }
3076 if (fd->flags&FD_TOOLONGFRAGMENT0x0010) {
3077 fei=proto_tree_add_boolean(fet,
3078 *(fit->hf_fragment_too_long_fragment),
3079 tvb, 0, 0,
3080 true1);
3081 proto_item_set_generated(fei);
3082 }
3083 }
3084}
3085
3086static bool_Bool
3087show_fragment_errs_in_col(fragment_head *fd_head, const fragment_items *fit,
3088 packet_info *pinfo)
3089{
3090 if (fd_head->flags & (FD_OVERLAPCONFLICT0x0004
3091 |FD_MULTIPLETAILS0x0008|FD_TOOLONGFRAGMENT0x0010) ) {
3092 col_add_fstr(pinfo->cinfo, COL_INFO, "[Illegal %s]", fit->tag);
3093 return true1;
3094 }
3095
3096 return false0;
3097}
3098
3099/* This function will build the fragment subtree; it's for fragments
3100 reassembled with "fragment_add()".
3101
3102 It will return true if there were fragmentation errors
3103 or false if fragmentation was ok.
3104*/
3105bool_Bool
3106show_fragment_tree(fragment_head *fd_head, const fragment_items *fit,
3107 proto_tree *tree, packet_info *pinfo, tvbuff_t *tvb, proto_item **fi)
3108{
3109 fragment_item *fd;
3110 proto_tree *ft;
3111 bool_Bool first_frag;
3112 uint32_t count = 0;
3113 /* It's not fragmented. */
3114 pinfo->fragmented = false0;
3115
3116 *fi = proto_tree_add_item(tree, *(fit->hf_fragments), tvb, 0, -1, ENC_NA0x00000000);
3117 proto_item_set_generated(*fi);
3118
3119 ft = proto_item_add_subtree(*fi, *(fit->ett_fragments));
3120 first_frag = true1;
3121 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next) {
3122 count++;
3123 }
3124 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next) {
3125 show_fragment(fd, fd->offset, fit, ft, *fi, first_frag, count, tvb, pinfo);
3126 first_frag = false0;
3127 }
3128
3129 if (fit->hf_fragment_count) {
3130 proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_fragment_count),
3131 tvb, 0, 0, count);
3132 proto_item_set_generated(fli);
3133 }
3134
3135 if (fit->hf_reassembled_length) {
3136 proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_reassembled_length),
3137 tvb, 0, 0, tvb_captured_length (tvb));
3138 proto_item_set_generated(fli);
3139 }
3140
3141 if (fit->hf_reassembled_data) {
3142 proto_item *fli = proto_tree_add_item(ft, *(fit->hf_reassembled_data),
3143 tvb, 0, tvb_captured_length(tvb), ENC_NA0x00000000);
3144 proto_item_set_generated(fli);
3145 }
3146
3147 return show_fragment_errs_in_col(fd_head, fit, pinfo);
3148}
3149
3150/* This function will build the fragment subtree; it's for fragments
3151 reassembled with "fragment_add_seq()" or "fragment_add_seq_check()".
3152
3153 It will return true if there were fragmentation errors
3154 or false if fragmentation was ok.
3155*/
3156bool_Bool
3157show_fragment_seq_tree(fragment_head *fd_head, const fragment_items *fit,
3158 proto_tree *tree, packet_info *pinfo, tvbuff_t *tvb, proto_item **fi)
3159{
3160 uint32_t offset, next_offset, count = 0;
3161 fragment_item *fd, *last_fd;
3162 proto_tree *ft;
3163 bool_Bool first_frag;
3164
3165 /* It's not fragmented. */
3166 pinfo->fragmented = false0;
3167
3168 *fi = proto_tree_add_item(tree, *(fit->hf_fragments), tvb, 0, -1, ENC_NA0x00000000);
3169 proto_item_set_generated(*fi);
3170
3171 ft = proto_item_add_subtree(*fi, *(fit->ett_fragments));
3172 offset = 0;
3173 next_offset = 0;
3174 last_fd = NULL((void*)0);
3175 first_frag = true1;
3176 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next){
3177 count++;
3178 }
3179 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next){
3180 if (last_fd == NULL((void*)0) || last_fd->offset != fd->offset) {
3181 offset = next_offset;
3182 next_offset += fd->len;
3183 }
3184 last_fd = fd;
3185 show_fragment(fd, offset, fit, ft, *fi, first_frag, count, tvb, pinfo);
3186 first_frag = false0;
3187 }
3188
3189 if (fit->hf_fragment_count) {
3190 proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_fragment_count),
3191 tvb, 0, 0, count);
3192 proto_item_set_generated(fli);
3193 }
3194
3195 if (fit->hf_reassembled_length) {
3196 proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_reassembled_length),
3197 tvb, 0, 0, tvb_captured_length (tvb));
3198 proto_item_set_generated(fli);
3199 }
3200
3201 if (fit->hf_reassembled_data) {
3202 proto_item *fli = proto_tree_add_item(ft, *(fit->hf_reassembled_data),
3203 tvb, 0, tvb_captured_length(tvb), ENC_NA0x00000000);
3204 proto_item_set_generated(fli);
3205 }
3206
3207 return show_fragment_errs_in_col(fd_head, fit, pinfo);
3208}
3209
3210static void
3211reassembly_table_init_reg_table(void *p, void *user_data _U___attribute__((unused)))
3212{
3213 register_reassembly_table_t* reg_table = (register_reassembly_table_t*)p;
3214 reassembly_table_init(reg_table->table, reg_table->funcs);
3215}
3216
3217static void
3218reassembly_table_init_reg_tables(void)
3219{
3220 g_list_foreach(reassembly_table_list, reassembly_table_init_reg_table, NULL((void*)0));
3221}
3222
3223static void
3224reassembly_table_cleanup_reg_table(void *p, void *user_data _U___attribute__((unused)))
3225{
3226 register_reassembly_table_t* reg_table = (register_reassembly_table_t*)p;
3227 reassembly_table_destroy(reg_table->table);
3228}
3229
3230static void
3231reassembly_table_cleanup_reg_tables(void)
3232{
3233 g_list_foreach(reassembly_table_list, reassembly_table_cleanup_reg_table, NULL((void*)0));
3234}
3235
3236void reassembly_tables_init(void)
3237{
3238 register_init_routine(&reassembly_table_init_reg_tables);
3239 register_cleanup_routine(&reassembly_table_cleanup_reg_tables);
3240}
3241
3242static void
3243reassembly_table_free(void *p, void *user_data _U___attribute__((unused)))
3244{
3245 register_reassembly_table_t* reg_table = (register_reassembly_table_t*)p;
3246 reassembly_table_destroy(reg_table->table);
3247 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)
;
3248}
3249
3250void
3251reassembly_table_cleanup(void)
3252{
3253 g_list_foreach(reassembly_table_list, reassembly_table_free, NULL((void*)0));
3254 g_list_free(reassembly_table_list);
3255}
3256
3257/* One instance of this structure is created for each pdu that spans across
3258 * multiple segments. (MSP) */
3259typedef struct _multisegment_pdu_t {
3260 uint64_t first_frame;
3261 uint64_t last_frame;
3262 unsigned start_offset_at_first_frame;
3263 unsigned end_offset_at_last_frame;
3264 int length; /* length of this MSP */
3265 uint32_t streaming_reassembly_id;
3266 /* pointer to previous multisegment_pdu */
3267 struct _multisegment_pdu_t* prev_msp;
3268} multisegment_pdu_t;
3269
3270/* struct for keeping the reassembly information of each stream */
3271struct streaming_reassembly_info_t {
3272 /* This map is keyed by frame num and keeps track of all MSPs for this
3273 * stream. Different frames will point to the same MSP if they contain
3274 * part data of this MSP. If a frame contains data that
3275 * belongs to two MSPs, it will point to the second MSP. */
3276 wmem_map_t* multisegment_pdus;
3277 /* This map is keyed by frame num and keeps track of the frag_offset
3278 * of the first byte of frames for fragment_add() after first scan. */
3279 wmem_map_t* frame_num_frag_offset_map;
3280 /* how many bytes the current uncompleted MSP still needs. (only valid for first scan) */
3281 int prev_deseg_len;
3282 /* the current uncompleted MSP (only valid for first scan) */
3283 multisegment_pdu_t* last_msp;
3284};
3285
3286static uint32_t
3287create_streaming_reassembly_id(void)
3288{
3289 static uint32_t global_streaming_reassembly_id = 0;
3290 return ++global_streaming_reassembly_id;
3291}
3292
3293streaming_reassembly_info_t*
3294streaming_reassembly_info_new(void)
3295{
3296 return wmem_new0(wmem_file_scope(), streaming_reassembly_info_t)((streaming_reassembly_info_t*)wmem_alloc0((wmem_file_scope()
), sizeof(streaming_reassembly_info_t)))
;
3297}
3298
3299/* Following is an example of ProtoA and ProtoB protocols from the declaration of this function in 'reassemble.h':
3300 *
3301 * +------------------ A Multisegment PDU of ProtoB ----------------------+
3302 * | |
3303 * +--- ProtoA payload1 ---+ +- payload2 -+ +- Payload3 -+ +- Payload4 -+ +- ProtoA payload5 -+
3304 * | EoMSP | OmNFP | BoMSP | | MoMSP | | MoMSP | | MoMSP | | EoMSP | BoMSP |
3305 * +-------+-------+-------+ +------------+ +------------+ +------------+ +---------+---------+
3306 * | |
3307 * +----------------------------------------------------------------------+
3308 *
3309 * For a ProtoA payload composed of EoMSP + OmNFP + BoMSP will call fragment_add() twice on EoMSP and BoMSP; and call
3310 * process_reassembled_data() once for generating tvb of a MSP to which EoMSP belongs; and call subdissector twice on
3311 * reassembled MSP of EoMSP and OmNFP + BoMSP. After that finds BoMSP is a beginning of a MSP at first scan.
3312 *
3313 * The rules are:
3314 *
3315 * - If a ProtoA payload contains EoMSP, we will need call fragment_add(), process_reassembled_data() and subdissector
3316 * once on it to end a MSP. (May run twice or more times at first scan, because subdissector may only return the
3317 * head length of message by pinfo->desegment_len. We need run second time for subdissector to determine the length
3318 * of entire message).
3319 *
3320 * - If a ProtoA payload contains OmNFP, we will need only call subdissector once on it. The subdissector need dissect
3321 * all non-fragment PDUs in it. (no desegment_len should output)
3322 *
3323 * - If a ProtoA payload contains BoMSP, we will need call subdissector once on BoMSP or OmNFP+BoMSP (because unknown
3324 * during first scan). The subdissector will output desegment_len (!= 0). Then we will call fragment_add()
3325 * with a new reassembly id on BoMSP for starting a new MSP.
3326 *
3327 * - If a ProtoA payload only contains MoMSP (entire payload is part of a MSP), we will only call fragment_add() once
3328 * or twice (at first scan) on it. The subdissector will not be called.
3329 *
3330 * In this implementation, only multisegment PDUs are recorded in multisegment_pdus map keyed by the numbers (uint64_t)
3331 * of frames belongs to MSPs. Each MSP in the map has a pointer referred to previous MSP, because we may need
3332 * two MSPs to dissect a ProtoA payload that contains EoMSP + BoMSP at the same time. The multisegment_pdus map is built
3333 * during first scan (pinfo->visited == false) with help of prev_deseg_len and last_msp fields of streaming_reassembly_info_t
3334 * for each direction of a ProtoA STREAM. The prev_deseg_len record how many bytes of subsequent ProtoA payloads belong to
3335 * previous PDU during first scan. The last_msp member of streaming_reassembly_info_t is always point to last MSP which
3336 * is created during scan previous or early ProtoA payloads. Since subdissector might return only the head length of entire
3337 * message (by pinfo->desegment_len) when there is not enough data to determine the message length, we need to reopen
3338 * reassembly fragments for adding more bytes during scanning the next ProtoA payload. We have to use fragment_add()
3339 * instead of fragment_add_check() or fragment_add_seq_next().
3340 *
3341 * Read more: please refer to comments of the declaration of this function in 'reassemble.h'.
3342 */
3343int
3344reassemble_streaming_data_and_call_subdissector(
3345 tvbuff_t* tvb, packet_info* pinfo, unsigned offset, int length,
3346 proto_tree* segment_tree, proto_tree* reassembled_tree, reassembly_table streaming_reassembly_table,
3347 streaming_reassembly_info_t* reassembly_info, uint64_t cur_frame_num,
3348 dissector_handle_t subdissector_handle, proto_tree* subdissector_tree, void* subdissector_data,
3349 const char* label, const fragment_items* frag_hf_items, int hf_segment_data
3350)
3351{
3352 int orig_length = length;
3353 int datalen = 0;
3354 int bytes_belong_to_prev_msp = 0; /* bytes belong to previous MSP */
3355 uint32_t reassembly_id = 0, frag_offset = 0;
3356 fragment_head* head = NULL((void*)0);
3357 bool_Bool need_more = false0;
3358 bool_Bool found_BoMSP = false0;
3359 multisegment_pdu_t* cur_msp = NULL((void*)0), * prev_msp = NULL((void*)0);
3360 uint16_t save_can_desegment;
3361 int save_desegment_offset;
3362 uint32_t save_desegment_len;
3363 uint64_t* frame_ptr;
3364
3365 save_can_desegment = pinfo->can_desegment;
3366 save_desegment_offset = pinfo->desegment_offset;
3367 save_desegment_len = pinfo->desegment_len;
3368
3369 /* calculate how many bytes of this payload belongs to previous MSP (EoMSP) */
3370 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3371 /* this is first scan */
3372 if (reassembly_info->prev_deseg_len == DESEGMENT_ONE_MORE_SEGMENT0x0fffffff) {
3373 /* assuming the entire tvb belongs to the previous MSP */
3374 bytes_belong_to_prev_msp = length;
3375 reassembly_info->prev_deseg_len = length;
3376 } else if (reassembly_info->prev_deseg_len > 0) {
3377 /* part or all of current payload belong to previous MSP */
3378 bytes_belong_to_prev_msp = MIN(reassembly_info->prev_deseg_len, length)(((reassembly_info->prev_deseg_len) < (length)) ? (reassembly_info
->prev_deseg_len) : (length))
;
3379 reassembly_info->prev_deseg_len -= bytes_belong_to_prev_msp;
3380 need_more = (reassembly_info->prev_deseg_len > 0);
3381 } /* else { beginning of a new PDU (might be a NFP or MSP) } */
3382
3383 if (bytes_belong_to_prev_msp > 0) {
3384 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", 3384, "reassembly_info->last_msp != ((void*)0)"
))))
;
3385 reassembly_id = reassembly_info->last_msp->streaming_reassembly_id;
3386 frag_offset = reassembly_info->last_msp->length;
3387 if (reassembly_info->frame_num_frag_offset_map == NULL((void*)0)) {
3388 reassembly_info->frame_num_frag_offset_map = wmem_map_new(wmem_file_scope(), g_int64_hash, g_int64_equal);
3389 }
3390 frame_ptr = (uint64_t*)wmem_memdup(wmem_file_scope(), &cur_frame_num, sizeof(uint64_t));
3391 wmem_map_insert(reassembly_info->frame_num_frag_offset_map, frame_ptr, GUINT_TO_POINTER(frag_offset)((gpointer) (gulong) (frag_offset)));
3392 /* This payload contains the data of previous msp, so we point to it. That may be overridden late. */
3393 wmem_map_insert(reassembly_info->multisegment_pdus, frame_ptr, reassembly_info->last_msp);
3394 }
3395 } else {
3396 /* not first scan, use information of multisegment_pdus built during first scan */
3397 if (reassembly_info->multisegment_pdus) {
3398 cur_msp = (multisegment_pdu_t*)wmem_map_lookup(reassembly_info->multisegment_pdus, &cur_frame_num);
3399 }
3400 if (cur_msp) {
3401 if (cur_msp->first_frame == cur_frame_num) {
3402 /* Current payload contains a beginning of a MSP. (BoMSP)
3403 * The cur_msp contains information about the beginning MSP.
3404 * If prev_msp is not null, that means this payload also contains
3405 * the last part of previous MSP. (EoMSP) */
3406 prev_msp = cur_msp->prev_msp;
3407 } else {
3408 /* Current payload is not a first frame of a MSP (not include BoMSP). */
3409 prev_msp = cur_msp;
3410 cur_msp = NULL((void*)0);
3411 }
3412 }
3413
3414 if (prev_msp && prev_msp->last_frame >= cur_frame_num) {
3415 if (prev_msp->last_frame == cur_frame_num) {
3416 /* this payload contains part of previous MSP (contains EoMSP) */
3417 bytes_belong_to_prev_msp = prev_msp->end_offset_at_last_frame - offset;
3418 } else { /* if (prev_msp->last_frame > cur_frame_num) */
3419 /* this payload all belongs to previous MSP */
3420 bytes_belong_to_prev_msp = length;
3421 need_more = true1;
3422 }
3423 reassembly_id = prev_msp->streaming_reassembly_id;
3424 }
3425 if (reassembly_info->frame_num_frag_offset_map) {
3426 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)))
;
3427 }
3428 }
3429
3430 /* handling EoMSP or MoMSP (entire payload being middle part of a MSP) */
3431 while (bytes_belong_to_prev_msp > 0) {
3432 tvbuff_t* reassembled_tvb = NULL((void*)0);
3433 DISSECTOR_ASSERT(reassembly_id > 0)((void) ((reassembly_id > 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3433,
"reassembly_id > 0"))))
;
3434 pinfo->can_desegment = 2; /* this will be decreased one while passing to subdissector */
3435 pinfo->desegment_offset = 0;
3436 pinfo->desegment_len = 0;
3437
3438 head = fragment_add(&streaming_reassembly_table, tvb, offset, pinfo, reassembly_id, NULL((void*)0),
3439 frag_offset, bytes_belong_to_prev_msp, need_more);
3440
3441 if (head) {
3442 if (frag_hf_items->hf_reassembled_in) {
3443 proto_item_set_generated(
3444 proto_tree_add_uint(segment_tree, *(frag_hf_items->hf_reassembled_in), tvb, offset,
3445 bytes_belong_to_prev_msp, head->reassembled_in)
3446 );
3447 }
3448
3449 if (!need_more) {
3450 reassembled_tvb = process_reassembled_data(tvb, offset, pinfo,
3451 wmem_strdup_printf(pinfo->pool, "Reassembled %s", label),
3452 head, frag_hf_items, NULL((void*)0), reassembled_tree);
3453 }
3454 }
3455
3456 proto_tree_add_bytes_format(segment_tree, hf_segment_data, tvb, offset,
3457 bytes_belong_to_prev_msp, NULL((void*)0), "%s Segment data (%u byte%s)", label,
3458 bytes_belong_to_prev_msp, plurality(bytes_belong_to_prev_msp, "", "s")((bytes_belong_to_prev_msp) == 1 ? ("") : ("s")));
3459
3460 if (reassembled_tvb) {
3461 /* normally, this stage will dissect one or more completed pdus */
3462 /* Note, don't call_dissector_with_data because sometime the pinfo->curr_layer_num will changed
3463 * after calling that will make reassembly failed! */
3464 call_dissector_only(subdissector_handle, reassembled_tvb, pinfo, subdissector_tree, subdissector_data);
3465 }
3466
3467 if (pinfo->desegment_len) {
3468 /* that must only happen during first scan the reassembly_info->prev_deseg_len might be only the
3469 * head length of entire message. */
3470 DISSECTOR_ASSERT(!PINFO_FD_VISITED(pinfo))((void) ((!((pinfo)->fd->visited)) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3470,
"!((pinfo)->fd->visited)"))))
;
3471 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", 3473, "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."
))))
3472 "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", 3473, "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."
))))
3473 " 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", 3473, "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."
))))
;
3474
3475 if (pinfo->desegment_offset > 0) {
3476 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", 3480, "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
)))))
3477 && 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", 3480, "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
)))))
3478 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", 3480, "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
)))))
3479 "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", 3480, "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
)))))
3480 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", 3480, "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
)))))
;
3481
3482 /* shorten the bytes_belong_to_prev_msp and just truncate the reassembled tvb */
3483 bytes_belong_to_prev_msp = pinfo->desegment_offset - reassembly_info->last_msp->length;
3484 fragment_truncate(&streaming_reassembly_table, pinfo, reassembly_id, NULL((void*)0), pinfo->desegment_offset);
3485 found_BoMSP = true1;
3486 } else {
3487 if (pinfo->desegment_len == DESEGMENT_ONE_MORE_SEGMENT0x0fffffff) {
3488 /* just need more bytes, all remaining bytes belongs to previous MSP (to run fragment_add again) */
3489 bytes_belong_to_prev_msp = length;
3490 }
3491
3492 /* Remove the data added by previous fragment_add(), and reopen fragments for adding more bytes. */
3493 fragment_truncate(&streaming_reassembly_table, pinfo, reassembly_id, NULL((void*)0), reassembly_info->last_msp->length);
3494 fragment_set_partial_reassembly(&streaming_reassembly_table, pinfo, reassembly_id, NULL((void*)0));
3495
3496 reassembly_info->prev_deseg_len = bytes_belong_to_prev_msp + pinfo->desegment_len;
3497 bytes_belong_to_prev_msp = MIN(reassembly_info->prev_deseg_len, length)(((reassembly_info->prev_deseg_len) < (length)) ? (reassembly_info
->prev_deseg_len) : (length))
;
3498 reassembly_info->prev_deseg_len -= bytes_belong_to_prev_msp;
3499 need_more = (reassembly_info->prev_deseg_len > 0);
3500 continue;
3501 }
3502 }
3503
3504 if (pinfo->desegment_len == 0 || found_BoMSP) {
3505 /* We will arrive here, only when the MSP is defragmented and dissected or this
3506 * payload all belongs to previous MSP (only fragment_add() with need_more=true called)
3507 * or BoMSP is parsed while pinfo->desegment_offset > 0 and pinfo->desegment_len != 0
3508 */
3509 offset += bytes_belong_to_prev_msp;
3510 length -= bytes_belong_to_prev_msp;
3511 DISSECTOR_ASSERT(length >= 0)((void) ((length >= 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3511,
"length >= 0"))))
;
3512 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3513 reassembly_info->last_msp->length += bytes_belong_to_prev_msp;
3514 }
3515
3516 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited) && reassembled_tvb) {
3517 /* completed current msp */
3518 reassembly_info->last_msp->last_frame = cur_frame_num;
3519 reassembly_info->last_msp->end_offset_at_last_frame = offset;
3520 reassembly_info->prev_deseg_len = pinfo->desegment_len;
3521 }
3522 bytes_belong_to_prev_msp = 0; /* break */
3523 }
3524 }
3525
3526 /* to find and handle OmNFP, and find BoMSP at first scan. */
3527 if (length > 0 && !found_BoMSP) {
3528 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3529 /* It is first scan, to dissect remaining bytes to find whether it is OmNFP only, or BoMSP only or OmNFP + BoMSP. */
3530 datalen = length;
3531 DISSECTOR_ASSERT(cur_msp == NULL)((void) ((cur_msp == ((void*)0)) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3531,
"cur_msp == ((void*)0)"))))
;
3532 } else {
3533 /* Not first scan */
3534 if (cur_msp) {
3535 /* There's a BoMSP. Let's calculate the length of OmNFP between EoMSP and BoMSP */
3536 datalen = cur_msp->start_offset_at_first_frame - offset; /* if result is zero that means no OmNFP */
3537 } else {
3538 /* This payload is not a beginning of MSP. The remaining bytes all belong to OmNFP without BoMSP */
3539 datalen = length;
3540 }
3541 }
3542 DISSECTOR_ASSERT(datalen >= 0)((void) ((datalen >= 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3542,
"datalen >= 0"))))
;
3543
3544 /* Dissect the remaining of this payload. If (datalen == 0) means remaining only have one BoMSP without OmNFP. */
3545 if (datalen > 0) {
3546 /* we dissect if it is not dissected before or it is a non-fragment pdu (between two multisegment pdus) */
3547 pinfo->can_desegment = 2;
3548 pinfo->desegment_offset = 0;
3549 pinfo->desegment_len = 0;
3550
3551 call_dissector_only(subdissector_handle, tvb_new_subset_length(tvb, offset, datalen),
3552 pinfo, subdissector_tree, subdissector_data);
3553
3554 if (pinfo->desegment_len) {
3555 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", 3557, "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."
))))
3556 "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", 3557, "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."
))))
3557 " 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", 3557, "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."
))))
;
3558 /* only happen during first scan */
3559 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", 3559, "!((pinfo)->fd->visited) && datalen == length"
))))
;
3560 offset += pinfo->desegment_offset;
3561 length -= pinfo->desegment_offset;
3562 } else {
3563 /* all remaining bytes are consumed by subdissector */
3564 offset += datalen;
3565 length -= datalen;
3566 }
3567 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3568 reassembly_info->prev_deseg_len = pinfo->desegment_len;
3569 }
3570 } /* else all remaining bytes (BoMSP) belong to a new MSP */
3571 DISSECTOR_ASSERT(length >= 0)((void) ((length >= 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3571,
"length >= 0"))))
;
3572 }
3573
3574 /* handling BoMSP */
3575 if (length > 0) {
3576 col_append_sep_fstr(pinfo->cinfo, COL_INFO, " ", "[%s segment of a reassembled PDU] ", label);
3577 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3578 /* create a msp for current frame during first scan */
3579 cur_msp = wmem_new0(wmem_file_scope(), multisegment_pdu_t)((multisegment_pdu_t*)wmem_alloc0((wmem_file_scope()), sizeof
(multisegment_pdu_t)))
;
3580 cur_msp->first_frame = cur_frame_num;
3581 cur_msp->last_frame = UINT64_MAX(18446744073709551615UL);
3582 cur_msp->start_offset_at_first_frame = offset;
3583 cur_msp->length = length;
3584 cur_msp->streaming_reassembly_id = reassembly_id = create_streaming_reassembly_id();
3585 cur_msp->prev_msp = reassembly_info->last_msp;
3586 reassembly_info->last_msp = cur_msp;
3587 if (reassembly_info->multisegment_pdus == NULL((void*)0)) {
3588 reassembly_info->multisegment_pdus = wmem_map_new(wmem_file_scope(), g_int64_hash, g_int64_equal);
3589 }
3590 frame_ptr = (uint64_t*)wmem_memdup(wmem_file_scope(), &cur_frame_num, sizeof(uint64_t));
3591 wmem_map_insert(reassembly_info->multisegment_pdus, frame_ptr, cur_msp);
3592 } else {
3593 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", 3593, "cur_msp && cur_msp->start_offset_at_first_frame == offset"
))))
;
3594 reassembly_id = cur_msp->streaming_reassembly_id;
3595 }
3596 /* add first fragment of the new MSP to reassembly table */
3597 head = fragment_add(&streaming_reassembly_table, tvb, offset, pinfo, reassembly_id,
3598 NULL((void*)0), 0, length, true1);
3599
3600 if (head && frag_hf_items->hf_reassembled_in) {
3601 proto_item_set_generated(
3602 proto_tree_add_uint(segment_tree, *(frag_hf_items->hf_reassembled_in),
3603 tvb, offset, length, head->reassembled_in)
3604 );
3605 }
3606 proto_tree_add_bytes_format(segment_tree, hf_segment_data, tvb, offset, length,
3607 NULL((void*)0), "%s Segment data (%u byte%s)", label, length, plurality(length, "", "s")((length) == 1 ? ("") : ("s")));
3608 }
3609
3610 pinfo->can_desegment = save_can_desegment;
3611 pinfo->desegment_offset = save_desegment_offset;
3612 pinfo->desegment_len = save_desegment_len;
3613
3614 return orig_length;
3615}
3616
3617int
3618additional_bytes_expected_to_complete_reassembly(streaming_reassembly_info_t* reassembly_info)
3619{
3620 return reassembly_info->prev_deseg_len;
3621}
3622
3623/*
3624 * Editor modelines - https://www.wireshark.org/tools/modelines.html
3625 *
3626 * Local variables:
3627 * c-basic-offset: 8
3628 * tab-width: 8
3629 * indent-tabs-mode: t
3630 * End:
3631 *
3632 * vi: set shiftwidth=8 tabstop=8 noexpandtab:
3633 * :indentSize=8:tabSize=8:noTabs=false:
3634 */