Bug Summary

File:builds/wireshark/wireshark/epan/reassemble.c
Warning:line 1524, column 6
Potential leak of memory pointed to by 'data'

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name reassemble.c -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 2 -fhalf-no-semantic-interposition -fno-delete-null-pointer-checks -mframe-pointer=all -relaxed-aliasing -fmath-errno -ffp-contract=on -fno-rounding-math -ffloat16-excess-precision=fast -fbfloat16-excess-precision=fast -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/builds/wireshark/wireshark/build -fcoverage-compilation-dir=/builds/wireshark/wireshark/build -resource-dir /usr/lib/llvm-22/lib/clang/22 -isystem /usr/include/glib-2.0 -isystem /usr/lib/x86_64-linux-gnu/glib-2.0/include -isystem /builds/wireshark/wireshark/epan -isystem /builds/wireshark/wireshark/build/epan -isystem /usr/include/mit-krb5 -isystem /usr/include/lua5.5 -isystem /usr/include/libxml2 -D CARES_NO_DEPRECATED -D G_DISABLE_DEPRECATED -D G_DISABLE_SINGLE_INCLUDES -D WS_BUILD_DLL -D WS_DEBUG -D WS_DEBUG_UTF_8 -D epan_EXPORTS -I /builds/wireshark/wireshark/build -I /builds/wireshark/wireshark -I /builds/wireshark/wireshark/include -I /builds/wireshark/wireshark/wiretap -D _GLIBCXX_ASSERTIONS -internal-isystem /usr/lib/llvm-22/lib/clang/22/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/16/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fmacro-prefix-map=/builds/wireshark/wireshark/= -fmacro-prefix-map=/builds/wireshark/wireshark/build/= -fmacro-prefix-map=../= -Wno-format-nonliteral -std=gnu17 -ferror-limit 19 -fvisibility=hidden -fwrapv -fwrapv-pointer -fstrict-flex-arrays=3 -stack-protector 2 -fstack-clash-protection -fcf-protection=full -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fexceptions -fcolor-diagnostics -analyzer-output=html -faddrsig -fdwarf2-cfi-asm -o /builds/wireshark/wireshark/sbout/2026-07-06-100400-3595-1 -x c /builds/wireshark/wireshark/epan/reassemble.c
1/* reassemble.c
2 * Routines for {fragment,segment} reassembly
3 *
4 * Wireshark - Network traffic analyzer
5 * By Gerald Combs <[email protected]>
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
1477 * existing end. How much overlap? */
1478 overlap = dfpos - fd_i->offset;
1479 /* duplicate/retransmission/overlap */
1480 uint32_t cmp_len = MIN(fd_i->len,overlap)(((fd_i->len) < (overlap)) ? (fd_i->len) : (overlap)
)
;
1481
1482 fd_i->flags |= FD_OVERLAP0x0002;
1483 fd_head->flags |= FD_OVERLAP0x0002;
1484 if ( memcmp(data + fd_i->offset,
1485 tvb_get_ptr(fd_i->tvb_data, 0, cmp_len),
1486 cmp_len)
1487 ) {
1488 fd_i->flags |= FD_OVERLAPCONFLICT0x0004;
1489 fd_head->flags |= FD_OVERLAPCONFLICT0x0004;
1490 }
1491 }
1492 /* XXX: As in the fragment_add_seq funcs
1493 * like fragment_defragment_and_free() the
1494 * existing behavior does not overwrite
1495 * overlapping bytes even if there is a
1496 * conflict. It only adds new bytes.
1497 *
1498 * Since we only add fragments to a reassembly
1499 * if the reassembly isn't complete, the most
1500 * common case for overlap conflicts is when
1501 * an earlier reassembly isn't fully contained
1502 * in the capture, and we've reused an
1503 * identification number / wrapped around
1504 * offset sequence numbers much later in the
1505 * capture. In that case, we probably *do*
1506 * want to overwrite conflicting bytes, since
1507 * the earlier fragments didn't form a complete
1508 * reassembly and should be effectively thrown
1509 * out rather than mixed with the new ones?
1510 */
1511 if (fd_i->offset + fraglen > dfpos) {
1512 memcpy(data+dfpos,
1513 tvb_get_ptr(fd_i->tvb_data, overlap, fraglen-overlap),
1514 fraglen-overlap);
1515 dfpos = fd_i->offset + fraglen;
1516 }
1517 }
1518 /* Mark that this fragment as used and clear data. */
1519 fd_i->flags |= FD_DEFRAGMENTED0x0001;
1520 fragment_item_free_tvb(fd_i);
1521 }
1522 }
1523
1524 if (old_tvb_data)
28
Potential leak of memory pointed to by 'data'
1525 tvb_add_to_chain(tvb, old_tvb_data);
1526 /* mark this packet as defragmented.
1527 allows us to skip any trailing fragments */
1528 fd_head->flags |= FD_DEFRAGMENTED0x0001;
1529 fd_head->reassembled_in=pinfo->num;
1530 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
1531
1532 /* we don't throw until here to avoid leaking old_data and others */
1533 if (fd_head->error) {
1534 THROW_MESSAGE(ReassemblyError, fd_head->error)except_throw(1, (9), (fd_head->error));
1535 }
1536
1537 return true1;
1538}
1539
1540static fragment_head *
1541fragment_add_common(reassembly_table *table, tvbuff_t *tvb, const int offset,
1542 const packet_info *pinfo, const uint32_t id,
1543 const void *data, const uint32_t frag_offset,
1544 const uint32_t frag_data_len, const bool_Bool more_frags,
1545 const bool_Bool check_already_added,
1546 const uint32_t frag_frame)
1547{
1548 fragment_head *fd_head;
1549 fragment_item *fd_item;
1550 bool_Bool already_added;
1551
1552
1553 /*
1554 * Dissector shouldn't give us garbage tvb info.
1555 *
1556 * XXX - should this code take responsibility for preventing
1557 * reassembly if data is missing due to the packets being
1558 * sliced, rather than leaving it up to dissectors?
1559 */
1560 DISSECTOR_ASSERT(tvb_bytes_exist(tvb, offset, frag_data_len))((void) ((tvb_bytes_exist(tvb, offset, frag_data_len)) ? (void
)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/reassemble.c", 1560, "tvb_bytes_exist(tvb, offset, frag_data_len)"
))))
;
1561
1562 fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
1563
1564#if 0
1565 /* debug output of associated fragments. */
1566 /* leave it here for future debugging sessions */
1567 if(strcmp(pinfo->current_proto, "DCERPC") == 0) {
1568 printf("proto:%s num:%u id:%u offset:%u len:%u more:%u visited:%u\n",
1569 pinfo->current_proto, pinfo->num, id, frag_offset, frag_data_len, more_frags, pinfo->fd->visited);
1570 if(fd_head != NULL((void*)0)) {
1571 for(fd_item=fd_head->next;fd_item;fd_item=fd_item->next){
1572 printf("fd_frame:%u fd_offset:%u len:%u datalen:%u\n",
1573 fd_item->frame, fd_item->offset, fd_item->len, fd_item->datalen);
1574 }
1575 }
1576 }
1577#endif
1578
1579 /*
1580 * Is this the first pass through the capture?
1581 */
1582 if (!pinfo->fd->visited) {
1583 /*
1584 * Yes, so we could be doing reassembly. If
1585 * "check_already_added" is true, and fd_head is non-null,
1586 * meaning that this fragment would be added to an
1587 * in-progress reassembly, check if we have seen this
1588 * fragment before, i.e., if we have already added it to
1589 * that reassembly. That can be true even on the first pass
1590 * since we sometimes might call a subdissector multiple
1591 * times.
1592 *
1593 * We check both the frame number and the fragment offset,
1594 * so that we support multiple fragments from the same
1595 * frame being added to the same reassembled PDU.
1596 */
1597 if (check_already_added && fd_head != NULL((void*)0)) {
1598 /*
1599 * fd_head->frame is the maximum of the frame
1600 * numbers of all the fragments added to this
1601 * reassembly; if this frame is later than that
1602 * frame, we know it hasn't been added yet.
1603 */
1604 if (frag_frame <= fd_head->frame) {
1605 already_added = false0;
1606 /*
1607 * The first item in the reassembly list
1608 * is not a fragment, it's a data structure
1609 * for the reassembled packet, so we
1610 * start checking with the next item.
1611 */
1612 for (fd_item = fd_head->next; fd_item;
1613 fd_item = fd_item->next) {
1614 if (frag_frame == fd_item->frame &&
1615 frag_offset == fd_item->offset) {
1616 already_added = true1;
1617 break;
1618 }
1619 }
1620 if (already_added) {
1621 /*
1622 * Have we already finished
1623 * reassembling?
1624 */
1625 if (fd_head->flags & FD_DEFRAGMENTED0x0001) {
1626 /*
1627 * Yes.
1628 * XXX - can this ever happen?
1629 */
1630 THROW_MESSAGE(ReassemblyError,except_throw(1, (9), ("Frame already added in first pass"))
1631 "Frame already added in first pass")except_throw(1, (9), ("Frame already added in first pass"));
1632 } else {
1633 /*
1634 * No.
1635 */
1636 return NULL((void*)0);
1637 }
1638 }
1639 }
1640 }
1641 } else {
1642 /*
1643 * No, so we've already done all the reassembly and added
1644 * all the fragments. Do we have a reassembly and, if so,
1645 * have we finished reassembling?
1646 */
1647 if (fd_head != NULL((void*)0) && fd_head->flags & FD_DEFRAGMENTED0x0001) {
1648 /*
1649 * Yes. This is probably being done after the
1650 * first pass, and we've already done the work
1651 * on the first pass.
1652 *
1653 * If the reassembly got a fatal error, throw that
1654 * error again.
1655 */
1656 if (fd_head->error)
1657 THROW_MESSAGE(ReassemblyError, fd_head->error)except_throw(1, (9), (fd_head->error));
1658
1659 /*
1660 * Is it later in the capture than all of the
1661 * fragments in the reassembly?
1662 */
1663 if (frag_frame > fd_head->frame) {
1664 /*
1665 * Yes, so report this as a problem,
1666 * possibly a retransmission.
1667 */
1668 THROW_MESSAGE(ReassemblyError, "New fragment overlaps old data (retransmission?)")except_throw(1, (9), ("New fragment overlaps old data (retransmission?)"
))
;
1669 }
1670
1671 /*
1672 * Does this fragment go past the end of the
1673 * results of that reassembly?
1674 */
1675 if (frag_offset + frag_data_len > fd_head->datalen) {
1676 /*
1677 * Yes.
1678 */
1679 if (frag_offset >= fd_head->datalen) {
1680 /*
1681 * The fragment starts past the
1682 * end of the reassembled data.
1683 */
1684 THROW_MESSAGE(ReassemblyError, "New fragment past old data limits")except_throw(1, (9), ("New fragment past old data limits"));
1685 } else {
1686 /*
1687 * The fragment starts before the end
1688 * of the reassembled data, but
1689 * runs past the end. That could
1690 * just be a retransmission.
1691 */
1692 THROW_MESSAGE(ReassemblyError, "New fragment overlaps old data (retransmission?)")except_throw(1, (9), ("New fragment overlaps old data (retransmission?)"
))
;
1693 }
1694 }
1695
1696 return fd_head;
1697 } else {
1698 /*
1699 * No.
1700 */
1701 return NULL((void*)0);
1702 }
1703 }
1704
1705 if (fd_head==NULL((void*)0)){
1706 /* not found, this must be the first snooped fragment for this
1707 * packet. Create list-head.
1708 */
1709 fd_head = new_head(0);
1710
1711 /*
1712 * Insert it into the hash table.
1713 */
1714 insert_fd_head(table, fd_head, pinfo, id, data);
1715 }
1716
1717 if (fragment_add_work(fd_head, tvb, offset, pinfo, frag_offset,
1718 frag_data_len, more_frags, frag_frame, false0)) {
1719 /*
1720 * Reassembly is complete.
1721 */
1722 return fd_head;
1723 } else {
1724 /*
1725 * Reassembly isn't complete.
1726 */
1727 return NULL((void*)0);
1728 }
1729}
1730
1731fragment_head *
1732fragment_add(reassembly_table *table, tvbuff_t *tvb, const int offset,
1733 const packet_info *pinfo, const uint32_t id, const void *data,
1734 const uint32_t frag_offset, const uint32_t frag_data_len,
1735 const bool_Bool more_frags)
1736{
1737 return fragment_add_common(table, tvb, offset, pinfo, id, data,
1738 frag_offset, frag_data_len, more_frags, true1, pinfo->num);
1739}
1740
1741/*
1742 * For use when you can have multiple fragments in the same frame added
1743 * to the same reassembled PDU, e.g. with ONC RPC-over-TCP.
1744 */
1745fragment_head *
1746fragment_add_multiple_ok(reassembly_table *table, tvbuff_t *tvb,
1747 const int offset, const packet_info *pinfo,
1748 const uint32_t id, const void *data,
1749 const uint32_t frag_offset,
1750 const uint32_t frag_data_len, const bool_Bool more_frags)
1751{
1752 return fragment_add_common(table, tvb, offset, pinfo, id, data,
1753 frag_offset, frag_data_len, more_frags, false0, pinfo->num);
1754}
1755
1756/*
1757 * For use in protocols like TCP when you are adding an out of order segment
1758 * that arrived in an earlier frame because the correct fragment id could not
1759 * be determined until later. By allowing fd->frame to be different than
1760 * pinfo->num, show_fragment_tree will display the correct fragment numbers.
1761 *
1762 * Note that pinfo is still used to set reassembled_in if we have all the
1763 * fragments, so that results on subsequent passes can be the same as the
1764 * first pass.
1765 */
1766fragment_head *
1767fragment_add_out_of_order(reassembly_table *table, tvbuff_t *tvb,
1768 const int offset, const packet_info *pinfo,
1769 const uint32_t id, const void *data,
1770 const uint32_t frag_offset,
1771 const uint32_t frag_data_len,
1772 const bool_Bool more_frags, const uint32_t frag_frame)
1773{
1774 return fragment_add_common(table, tvb, offset, pinfo, id, data,
1775 frag_offset, frag_data_len, more_frags, true1, frag_frame);
1776}
1777
1778
1779static fragment_head *
1780fragment_add_check_common(reassembly_table *table, tvbuff_t *tvb, const int offset,
1781 const packet_info *pinfo, const uint32_t id,
1782 const void *data, uint32_t frag_offset,
1783 const uint32_t frag_data_len, const bool_Bool more_frags,
1784 const uint32_t flags, const uint32_t fallback_frame)
1785{
1786 reassembled_key reass_key;
1787 fragment_head *fd_head;
1788 void *orig_key;
1789 bool_Bool late_retransmission = false0;
1790
1791 /*
1792 * If this isn't the first pass, look for this frame in the table
1793 * of reassembled packets.
1794 */
1795 if (pinfo->fd->visited) {
2
Assuming field 'visited' is 0
3
Taking false branch
1796 reass_key.frame = pinfo->num;
1797 reass_key.id = id;
1798 return (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
1799 }
1800
1801 /* Looks up a key in the GHashTable, returning the original key and the associated value
1802 * and a bool which is true if the key was found. This is useful if you need to free
1803 * the memory allocated for the original key, for example before calling g_hash_table_remove()
1804 */
1805 fd_head = lookup_fd_head(table, pinfo, id, data, &orig_key);
1806 if ((fd_head == NULL((void*)0)) && (fallback_frame != pinfo->num)) {
4
Assuming 'fd_head' is not equal to NULL
1807 /* Check if there is completed reassembly reachable from fallback frame */
1808 reass_key.frame = fallback_frame;
1809 reass_key.id = id;
1810 fd_head = (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
1811 if (fd_head != NULL((void*)0)) {
1812 /* Found completely reassembled packet, hash it with current frame number */
1813 reassembled_key *new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc ((sizeof (reassembled_key) >
0 ? sizeof (reassembled_key) : 1)))
;
1814 new_key->frame = pinfo->num;
1815 new_key->id = id;
1816 reassembled_table_insert(table->reassembled_table, new_key, fd_head);
1817 late_retransmission = true1;
1818 }
1819 }
1820 if (fd_head
4.1
'fd_head' is not equal to NULL
== NULL((void*)0)) {
5
Taking false branch
1821 /* not found, this must be the first snooped fragment for this
1822 * packet. Create list-head.
1823 */
1824 fd_head = new_head(0);
1825
1826 if((flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001)
1827 && !more_frags) {
1828 /*
1829 * This is the last fragment for this packet, and
1830 * is the only one we've seen.
1831 *
1832 * We assume this is the first and only fragment for
1833 * this packet; just add the head of the list to
1834 * the table of reassembled packets.
1835 */
1836 /* To save memory, we don't actually copy the
1837 * fragment from the tvbuff to the fragment, and in
1838 * process_reassembled_data just return back a subset
1839 * of the original tvbuff (which must be passed in).
1840 */
1841 fd_head->datalen = frag_data_len;
1842 fd_head->reassembled_in=pinfo->num;
1843 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
1844 /*
1845 * Add this item to the table of reassembled packets.
1846 */
1847 fragment_reassembled(table, fd_head, pinfo, id);
1848 return fd_head;
1849 }
1850 /*
1851 * Save the key, for unhashing it later.
1852 */
1853 orig_key = insert_fd_head(table, fd_head, pinfo, id, data);
1854
1855 if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001)
1856 frag_offset = 0;
1857 } else {
1858 if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001) {
6
Taking true branch
1859 /* There are no gaps by construction, so we can
1860 * simply use the contiguous length. */
1861 frag_offset = fd_head->contiguous_len;
1862 }
1863 }
1864
1865 /*
1866 * If this is a short frame, then we can't, and don't, do
1867 * reassembly on it. We just give up.
1868 */
1869 if (!tvb_bytes_exist(tvb, offset, frag_data_len)) {
7
Assuming the condition is false
8
Taking false branch
1870 return NULL((void*)0);
1871 }
1872
1873 if (fragment_add_work(fd_head, tvb, offset, pinfo, frag_offset,
9
Calling 'fragment_add_work'
1874 frag_data_len, more_frags, pinfo->num, late_retransmission)) {
1875 /* Nothing left to do if it was a late retransmission */
1876 if (late_retransmission) {
1877 return fd_head;
1878 }
1879 /*
1880 * Reassembly is complete.
1881 * Remove this from the table of in-progress
1882 * reassemblies, add it to the table of
1883 * reassembled packets, and return it.
1884 */
1885
1886 /*
1887 * Remove this from the table of in-progress reassemblies,
1888 * and free up any memory used for it in that table.
1889 */
1890 fragment_unhash(table, orig_key);
1891
1892 /*
1893 * Add this item to the table of reassembled packets.
1894 */
1895 fragment_reassembled(table, fd_head, pinfo, id);
1896 return fd_head;
1897 } else {
1898 /*
1899 * Reassembly isn't complete.
1900 */
1901 return NULL((void*)0);
1902 }
1903}
1904
1905fragment_head *
1906fragment_add_check_with_fallback(reassembly_table *table, tvbuff_t *tvb, const int offset,
1907 const packet_info *pinfo, const uint32_t id,
1908 const void *data, const uint32_t frag_offset,
1909 const uint32_t frag_data_len, const bool_Bool more_frags,
1910 const uint32_t fallback_frame)
1911{
1912 return fragment_add_check_common(table, tvb, offset, pinfo, id, data,
1913 frag_offset, frag_data_len, more_frags, 0, fallback_frame);
1914}
1915
1916fragment_head *
1917fragment_add_check(reassembly_table *table, tvbuff_t *tvb, const int offset,
1918 const packet_info *pinfo, const uint32_t id,
1919 const void *data, const uint32_t frag_offset,
1920 const uint32_t frag_data_len, const bool_Bool more_frags)
1921{
1922 return fragment_add_check_common(table, tvb, offset, pinfo, id, data,
1923 frag_offset, frag_data_len, more_frags, 0, pinfo->num);
1924}
1925
1926fragment_head *
1927fragment_add_check_next(reassembly_table *table, tvbuff_t *tvb, const int offset,
1928 const packet_info *pinfo, const uint32_t id,
1929 const void *data,
1930 const uint32_t frag_data_len, const bool_Bool more_frags)
1931{
1932 return fragment_add_check_common(table, tvb, offset, pinfo, id, data,
1
Calling 'fragment_add_check_common'
1933 0, frag_data_len, more_frags, REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001, pinfo->num);
1934}
1935
1936static void
1937fragment_defragment_and_free (fragment_head *fd_head, const packet_info *pinfo)
1938{
1939 fragment_item *fd_i = NULL((void*)0);
1940 fragment_item *last_fd = NULL((void*)0);
1941 uint32_t dfpos = 0, old_dfpos = 0, size = 0;
1942 tvbuff_t *old_tvb_data = NULL((void*)0);
1943 uint8_t *data;
1944
1945 for(fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
1946 if(!last_fd || last_fd->offset!=fd_i->offset){
1947 size+=fd_i->len;
1948 }
1949 last_fd=fd_i;
1950 }
1951
1952 /* store old data in case the fd_i->data pointers refer to it */
1953 old_tvb_data=fd_head->tvb_data;
1954 data = (uint8_t *) g_malloc(size);
1955 fd_head->tvb_data = tvb_new_real_data(data, size, size);
1956 tvb_set_free_cb(fd_head->tvb_data, g_free);
1957 fd_head->len = size; /* record size for caller */
1958
1959 if (old_tvb_data) {
1960 dfpos = tvb_captured_length(old_tvb_data);
1961 memcpy(data, tvb_get_ptr(old_tvb_data, 0, dfpos), MIN(size, dfpos)(((size) < (dfpos)) ? (size) : (dfpos)));
1962 }
1963
1964 /* add all data fragments */
1965 last_fd=NULL((void*)0);
1966 dfpos = 0;
1967 for (fd_i=fd_head->next; fd_i; fd_i=fd_i->next) {
1968 if (fd_i->len) {
1969 if(!last_fd || last_fd->offset != fd_i->offset) {
1970 /* First fragment or in-sequence fragment */
1971 if (!(fd_i->flags & FD_DEFRAGMENTED0x0001)) {
1972 /* Already copied on the first pass */
1973 memcpy(data+dfpos, tvb_get_ptr(fd_i->tvb_data, 0, fd_i->len), fd_i->len);
1974 }
1975 /* But we need the position for overlap calculation of new fragments */
1976 old_dfpos = dfpos;
1977 dfpos += fd_i->len;
1978 } else if (!(fd_i->flags & FD_DEFRAGMENTED0x0001)){
1979 /* duplicate/retransmission/overlap */
1980 /* Note that overlaps of old fragments were already calculated. */
1981 fd_i->flags |= FD_OVERLAP0x0002;
1982 fd_head->flags |= FD_OVERLAP0x0002;
1983 if((old_dfpos + fd_i->len != dfpos)
1984 || tvb_memeql(fd_i->tvb_data, 0, data+old_dfpos, fd_i->len) ) {
1985 fd_i->flags |= FD_OVERLAPCONFLICT0x0004;
1986 fd_head->flags |= FD_OVERLAPCONFLICT0x0004;
1987 }
1988 }
1989 fragment_item_free_tvb(fd_i);
1990 fd_i->flags |= FD_DEFRAGMENTED0x0001;
1991 }
1992 last_fd=fd_i;
1993 }
1994
1995 if (old_tvb_data)
1996 tvb_free(old_tvb_data);
1997
1998 /* mark this packet as defragmented.
1999 * allows us to skip any trailing fragments.
2000 */
2001 fd_head->flags |= FD_DEFRAGMENTED0x0001;
2002 fd_head->reassembled_in=pinfo->num;
2003 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
2004}
2005
2006/*
2007 * This function adds a new fragment to the entry for a reassembly
2008 * operation.
2009 *
2010 * The list of fragments for a specific datagram is kept sorted for
2011 * easier handling.
2012 *
2013 * Returns true if we have all the fragments, false otherwise.
2014 *
2015 * This function assumes frag_number being a block sequence number.
2016 * The bsn for the first block is 0.
2017 */
2018static bool_Bool
2019fragment_add_seq_work(fragment_head *fd_head, tvbuff_t *tvb, const int offset,
2020 const packet_info *pinfo, const uint32_t frag_number,
2021 const uint32_t frag_data_len, const bool_Bool more_frags)
2022{
2023 fragment_item *fd;
2024 fragment_item *fd_i;
2025 fragment_item *last_fd;
2026 uint32_t max, dfpos;
2027 uint32_t frag_number_work;
2028
2029 /* Enables the use of fragment sequence numbers, which do not start with 0 */
2030 frag_number_work = frag_number;
2031 if ( fd_head->fragment_nr_offset != 0 )
2032 if ( frag_number_work >= fd_head->fragment_nr_offset )
2033 frag_number_work = frag_number - fd_head->fragment_nr_offset;
2034
2035 /* if the partial reassembly flag has been set, and we are extending
2036 * the pdu, un-reassemble the pdu. This means pointing old fds to malloc'ed data.
2037 */
2038 if(fd_head->flags & FD_DEFRAGMENTED0x0001 && frag_number_work >= fd_head->datalen &&
2039 fd_head->flags & FD_PARTIAL_REASSEMBLY0x0040){
2040
2041 fragment_reset_defragmentation(fd_head);
2042 }
2043
2044
2045 /* create new fd describing this fragment */
2046 fd = new_fragment_item(pinfo->num, frag_number_work, frag_data_len);
2047
2048 /* fd_head->frame is the maximum of the frame numbers of all the
2049 * fragments added to the reassembly. */
2050 if (fd->frame > fd_head->frame)
2051 fd_head->frame = fd->frame;
2052
2053 if (!more_frags) {
2054 /*
2055 * This is the tail fragment in the sequence.
2056 */
2057 if (fd_head->flags&FD_DATALEN_SET0x0400) {
2058 /* ok we have already seen other tails for this packet
2059 * it might be a duplicate.
2060 */
2061 if (fd_head->datalen != fd->offset ){
2062 /* Oops, this tail indicates a different packet
2063 * len than the previous ones. Something's wrong.
2064 */
2065 fd->flags |= FD_MULTIPLETAILS0x0008;
2066 fd_head->flags |= FD_MULTIPLETAILS0x0008;
2067 }
2068 } else {
2069 /* this was the first tail fragment, now we know the
2070 * sequence number of that fragment (which is NOT
2071 * the length of the packet!)
2072 */
2073 fd_head->datalen = fd->offset;
2074 fd_head->flags |= FD_DATALEN_SET0x0400;
2075 }
2076 }
2077
2078 /* If the packet is already defragmented, this MUST be an overlap.
2079 * The entire defragmented packet is in fd_head->data
2080 * Even if we have previously defragmented this packet, we still check
2081 * check it. Someone might play overlap and TTL games.
2082 */
2083 if (fd_head->flags & FD_DEFRAGMENTED0x0001) {
2084 fd->flags |= FD_OVERLAP0x0002|FD_DEFRAGMENTED0x0001;
2085 fd_head->flags |= FD_OVERLAP0x0002;
2086
2087 /* make sure it's not past the end */
2088 if (fd->offset > fd_head->datalen) {
2089 /* new fragment comes after the end */
2090 fd->flags |= FD_TOOLONGFRAGMENT0x0010;
2091 fd_head->flags |= FD_TOOLONGFRAGMENT0x0010;
2092 LINK_FRAG(fd_head,fd);
2093 return true1;
2094 }
2095 /* make sure it doesn't conflict with previous data */
2096 dfpos=0;
2097 last_fd=NULL((void*)0);
2098 for (fd_i=fd_head->next;fd_i && (fd_i->offset!=fd->offset);fd_i=fd_i->next) {
2099 if (!last_fd || last_fd->offset!=fd_i->offset){
2100 dfpos += fd_i->len;
2101 }
2102 last_fd=fd_i;
2103 }
2104 if(fd_i){
2105 /* new fragment overlaps existing fragment */
2106 if(fd_i->len!=fd->len){
2107 /*
2108 * They have different lengths; this
2109 * is definitely a conflict.
2110 */
2111 fd->flags |= FD_OVERLAPCONFLICT0x0004;
2112 fd_head->flags |= FD_OVERLAPCONFLICT0x0004;
2113 LINK_FRAG(fd_head,fd);
2114 return true1;
2115 }
2116 DISSECTOR_ASSERT(fd_head->len >= dfpos + fd->len)((void) ((fd_head->len >= dfpos + fd->len) ? (void)0
: (proto_report_dissector_bug("%s:%u: failed assertion \"%s\""
, "epan/reassemble.c", 2116, "fd_head->len >= dfpos + fd->len"
))))
;
2117 if (tvb_memeql(fd_head->tvb_data, dfpos,
2118 tvb_get_ptr(tvb,offset,fd->len),fd->len) ){
2119 /*
2120 * They have the same length, but the
2121 * data isn't the same.
2122 */
2123 fd->flags |= FD_OVERLAPCONFLICT0x0004;
2124 fd_head->flags |= FD_OVERLAPCONFLICT0x0004;
2125 LINK_FRAG(fd_head,fd);
2126 return true1;
2127 }
2128 /* it was just an overlap, link it and return */
2129 LINK_FRAG(fd_head,fd);
2130 return true1;
2131 } else {
2132 /*
2133 * New fragment doesn't overlap an existing
2134 * fragment - there was presumably a gap in
2135 * the sequence number space.
2136 *
2137 * XXX - what should we do here? Is it always
2138 * the case that there are no gaps, or are there
2139 * protcols using sequence numbers where there
2140 * can be gaps?
2141 *
2142 * If the former, the check below for having
2143 * received all the fragments should check for
2144 * holes in the sequence number space and for the
2145 * first sequence number being 0. If we do that,
2146 * the only way we can get here is if this fragment
2147 * is past the end of the sequence number space -
2148 * but the check for "fd->offset > fd_head->datalen"
2149 * would have caught that above, so it can't happen.
2150 *
2151 * If the latter, we don't have a good way of
2152 * knowing whether reassembly is complete if we
2153 * get packet out of order such that the "last"
2154 * fragment doesn't show up last - but, unless
2155 * in-order reliable delivery of fragments is
2156 * guaranteed, an implementation of the protocol
2157 * has no way of knowing whether reassembly is
2158 * complete, either.
2159 *
2160 * For now, we just link the fragment in and
2161 * return.
2162 */
2163 LINK_FRAG(fd_head,fd);
2164 return true1;
2165 }
2166 }
2167
2168 /* If we have reached this point, the packet is not defragmented yet.
2169 * Save all payload in a buffer until we can defragment.
2170 */
2171 /* check len, there may be a fragment with 0 len, that is actually the tail */
2172 if (fd->len) {
2173 if (!tvb_bytes_exist(tvb, offset, fd->len)) {
2174 /* abort if we didn't capture the entire fragment due
2175 * to a too-short snapshot length */
2176 g_slice_free(fragment_item, fd)do { if (1) g_slice_free1 (sizeof (fragment_item), (fd)); else
(void) ((fragment_item*) 0 == (fd)); } while (0)
;
2177 return false0;
2178 }
2179
2180 fd->tvb_data = tvb_clone_offset_len(tvb, offset, fd->len);
2181 }
2182 LINK_FRAG(fd_head,fd);
2183
2184
2185 if( !(fd_head->flags & FD_DATALEN_SET0x0400) ){
2186 /* if we don't know the sequence number of the last fragment,
2187 * there are definitely still missing packets. Cheaper than
2188 * the check below.
2189 */
2190 return false0;
2191 }
2192
2193
2194 /* check if we have received the entire fragment
2195 * this is easy since the list is sorted and the head is faked.
2196 * common case the whole list is scanned.
2197 */
2198 max = 0;
2199 for(fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
2200 if ( fd_i->offset==max ){
2201 max++;
2202 }
2203 }
2204 /* max will now be datalen+1 if all fragments have been seen */
2205
2206 if (max <= fd_head->datalen) {
2207 /* we have not received all packets yet */
2208 return false0;
2209 }
2210
2211
2212 if (max > (fd_head->datalen+1)) {
2213 /* oops, too long fragment detected */
2214 fd->flags |= FD_TOOLONGFRAGMENT0x0010;
2215 fd_head->flags |= FD_TOOLONGFRAGMENT0x0010;
2216 }
2217
2218
2219 /* we have received an entire packet, defragment it and
2220 * free all fragments
2221 */
2222 fragment_defragment_and_free(fd_head, pinfo);
2223
2224 return true1;
2225}
2226
2227/*
2228 * This function adds a new fragment to the fragment hash table.
2229 * If this is the first fragment seen for this datagram, a new entry
2230 * is created in the hash table, otherwise this fragment is just added
2231 * to the linked list of fragments for this packet.
2232 *
2233 * Returns a pointer to the head of the fragment data list if we have all the
2234 * fragments, NULL otherwise.
2235 *
2236 * This function assumes frag_number being a block sequence number.
2237 * The bsn for the first block is 0.
2238 */
2239static fragment_head *
2240fragment_add_seq_common(reassembly_table *table, tvbuff_t *tvb,
2241 const int offset, const packet_info *pinfo,
2242 const uint32_t id, const void *data,
2243 uint32_t frag_number, const uint32_t frag_data_len,
2244 const bool_Bool more_frags, const uint32_t flags,
2245 void * *orig_keyp)
2246{
2247 fragment_head *fd_head;
2248 void *orig_key;
2249
2250 fd_head = lookup_fd_head(table, pinfo, id, data, &orig_key);
2251
2252 /* have we already seen this frame ?*/
2253 if (pinfo->fd->visited) {
2254 if (fd_head != NULL((void*)0) && fd_head->flags & FD_DEFRAGMENTED0x0001) {
2255 if (orig_keyp != NULL((void*)0))
2256 *orig_keyp = orig_key;
2257 return fd_head;
2258 } else {
2259 return NULL((void*)0);
2260 }
2261 }
2262
2263 if (fd_head==NULL((void*)0)){
2264 /* not found, this must be the first snooped fragment for this
2265 * packet. Create list-head.
2266 */
2267 fd_head = new_head(FD_BLOCKSEQUENCE0x0100);
2268
2269 if((flags & (REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001|REASSEMBLE_FLAGS_802_11_HACK0x0002))
2270 && !more_frags) {
2271 /*
2272 * This is the last fragment for this packet, and
2273 * is the only one we've seen.
2274 *
2275 * Either we don't have sequence numbers, in which
2276 * case we assume this is the first fragment for
2277 * this packet, or we're doing special 802.11
2278 * processing, in which case we assume it's one
2279 * of those reassembled packets with a non-zero
2280 * fragment number (see packet-80211.c); just
2281 * return a pointer to the head of the list;
2282 * fragment_add_seq_check will then add it to the table
2283 * of reassembled packets.
2284 */
2285 if (orig_keyp != NULL((void*)0))
2286 *orig_keyp = NULL((void*)0);
2287 /* To save memory, we don't actually copy the
2288 * fragment from the tvbuff to the fragment, and in
2289 * process_reassembled_data just return back a subset
2290 * of the original tvbuff (which must be passed in).
2291 */
2292 fd_head->len = frag_data_len;
2293 fd_head->reassembled_in=pinfo->num;
2294 fd_head->reas_in_layer_num = pinfo->curr_layer_num;
2295 return fd_head;
2296 }
2297
2298 orig_key = insert_fd_head(table, fd_head, pinfo, id, data);
2299 if (orig_keyp != NULL((void*)0))
2300 *orig_keyp = orig_key;
2301
2302 /*
2303 * If we weren't given an initial fragment number,
2304 * make it 0.
2305 */
2306 if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001)
2307 frag_number = 0;
2308 } else {
2309 if (orig_keyp != NULL((void*)0))
2310 *orig_keyp = orig_key;
2311
2312 if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001) {
2313 fragment_item *fd;
2314 /*
2315 * If we weren't given an initial fragment number,
2316 * use the next expected fragment number as the fragment
2317 * number for this fragment.
2318 *
2319 * XXX - Use fd_head->first_gap to speed this up?
2320 */
2321 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next) {
2322 if (fd->next == NULL((void*)0))
2323 frag_number = fd->offset + 1;
2324 }
2325 }
2326 }
2327
2328 if (fragment_add_seq_work(fd_head, tvb, offset, pinfo,
2329 frag_number, frag_data_len, more_frags)) {
2330 /*
2331 * Reassembly is complete.
2332 */
2333 return fd_head;
2334 } else {
2335 /*
2336 * Reassembly isn't complete.
2337 */
2338 return NULL((void*)0);
2339 }
2340}
2341
2342fragment_head *
2343fragment_add_seq(reassembly_table *table, tvbuff_t *tvb, const int offset,
2344 const packet_info *pinfo, const uint32_t id, const void *data,
2345 const uint32_t frag_number, const uint32_t frag_data_len,
2346 const bool_Bool more_frags, const uint32_t flags)
2347{
2348 return fragment_add_seq_common(table, tvb, offset, pinfo, id, data,
2349 frag_number, frag_data_len,
2350 more_frags, flags, NULL((void*)0));
2351}
2352
2353/*
2354 * This does the work for "fragment_add_seq_check()" and
2355 * "fragment_add_seq_next()".
2356 *
2357 * This function assumes frag_number being a block sequence number.
2358 * The bsn for the first block is 0.
2359 *
2360 * If REASSEMBLE_FLAGS_NO_FRAG_NUMBER, it uses the next expected fragment number
2361 * as the fragment number if there is a reassembly in progress, otherwise
2362 * it uses 0.
2363 *
2364 * If not REASSEMBLE_FLAGS_NO_FRAG_NUMBER, it uses the "frag_number" argument as
2365 * the fragment number.
2366 *
2367 * If this is the first fragment seen for this datagram, a new
2368 * "fragment_head" structure is allocated to refer to the reassembled
2369 * packet.
2370 *
2371 * This fragment is added to the linked list of fragments for this packet.
2372 *
2373 * If "more_frags" is false and REASSEMBLE_FLAGS_802_11_HACK (as the name
2374 * implies, a special hack for 802.11) or REASSEMBLE_FLAGS_NO_FRAG_NUMBER
2375 * (implying messages must be in order since there's no sequence number) are
2376 * set in "flags", then this (one element) list is returned.
2377 *
2378 * If, after processing this fragment, we have all the fragments,
2379 * "fragment_add_seq_check_work()" removes that from the fragment hash
2380 * table if necessary and adds it to the table of reassembled fragments,
2381 * and returns a pointer to the head of the fragment list.
2382 *
2383 * Otherwise, it returns NULL.
2384 *
2385 * XXX - Should we simply return NULL for zero-length fragments?
2386 */
2387static fragment_head *
2388fragment_add_seq_check_work(reassembly_table *table, tvbuff_t *tvb,
2389 const int offset, const packet_info *pinfo,
2390 const uint32_t id, const void *data,
2391 const uint32_t frag_number,
2392 const uint32_t frag_data_len,
2393 const bool_Bool more_frags, const uint32_t flags)
2394{
2395 reassembled_key reass_key;
2396 fragment_head *fd_head;
2397 void *orig_key;
2398
2399 /*
2400 * Have we already seen this frame?
2401 * If so, look for it in the table of reassembled packets.
2402 */
2403 if (pinfo->fd->visited) {
2404 reass_key.frame = pinfo->num;
2405 reass_key.id = id;
2406 return (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
2407 }
2408
2409 fd_head = fragment_add_seq_common(table, tvb, offset, pinfo, id, data,
2410 frag_number, frag_data_len,
2411 more_frags,
2412 flags,
2413 &orig_key);
2414 if (fd_head) {
2415 /*
2416 * Reassembly is complete.
2417 *
2418 * If this is in the table of in-progress reassemblies,
2419 * remove it from that table. (It could be that this
2420 * was the first and last fragment, so that no
2421 * reassembly was done.)
2422 */
2423 if (orig_key != NULL((void*)0))
2424 fragment_unhash(table, orig_key);
2425
2426 /*
2427 * Add this item to the table of reassembled packets.
2428 */
2429 fragment_reassembled(table, fd_head, pinfo, id);
2430 return fd_head;
2431 } else {
2432 /*
2433 * Reassembly isn't complete.
2434 */
2435 return NULL((void*)0);
2436 }
2437}
2438
2439fragment_head *
2440fragment_add_seq_check(reassembly_table *table, tvbuff_t *tvb, const int offset,
2441 const packet_info *pinfo, const uint32_t id,
2442 const void *data,
2443 const uint32_t frag_number, const uint32_t frag_data_len,
2444 const bool_Bool more_frags)
2445{
2446 return fragment_add_seq_check_work(table, tvb, offset, pinfo, id, data,
2447 frag_number, frag_data_len,
2448 more_frags, 0);
2449}
2450
2451fragment_head *
2452fragment_add_seq_802_11(reassembly_table *table, tvbuff_t *tvb,
2453 const int offset, const packet_info *pinfo,
2454 const uint32_t id, const void *data,
2455 const uint32_t frag_number, const uint32_t frag_data_len,
2456 const bool_Bool more_frags)
2457{
2458 return fragment_add_seq_check_work(table, tvb, offset, pinfo, id, data,
2459 frag_number, frag_data_len,
2460 more_frags,
2461 REASSEMBLE_FLAGS_802_11_HACK0x0002);
2462}
2463
2464fragment_head *
2465fragment_add_seq_next(reassembly_table *table, tvbuff_t *tvb, const int offset,
2466 const packet_info *pinfo, const uint32_t id,
2467 const void *data, const uint32_t frag_data_len,
2468 const bool_Bool more_frags)
2469{
2470 /* Use a dummy frag_number (0), it is ignored since
2471 * REASSEMBLE_FLAGS_NO_FRAG_NUMBER is set. */
2472 return fragment_add_seq_check_work(table, tvb, offset, pinfo, id, data,
2473 0, frag_data_len, more_frags,
2474 REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001);
2475}
2476
2477static void
2478fragment_add_seq_single_move(reassembly_table *table, const packet_info *pinfo,
2479 const uint32_t id, const void *data,
2480 const uint32_t offset)
2481{
2482 fragment_head *fh, *new_fh;
2483 fragment_item *fd, *prev_fd;
2484 tvbuff_t *old_tvb_data;
2485 if (offset == 0) {
2486 return;
2487 }
2488 fh = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
2489 if (fh == NULL((void*)0)) {
2490 /* Shouldn't be called this way.
2491 * Probably wouldn't hurt to just create fh in this case. */
2492 ws_assert_not_reached()ws_log_fatal_full("", LOG_LEVEL_ERROR, "epan/reassemble.c", 2492
, __func__, "assertion \"not reached\" failed")
;
2493 return;
2494 }
2495 if (fh->flags & FD_DATALEN_SET0x0400 && fh->datalen <= offset) {
2496 /* Don't take from past the end. <= because we don't
2497 * want to take a First fragment from the next one
2498 * either */
2499 return;
2500 }
2501 new_fh = lookup_fd_head(table, pinfo, id+offset, data, NULL((void*)0));
2502 if (new_fh != NULL((void*)0)) {
2503 /* Attach to the end of the sorted list. */
2504 prev_fd = NULL((void*)0);
2505 for(fd = fh->next; fd != NULL((void*)0); fd=fd->next) {
2506 prev_fd = fd;
2507 }
2508 /* Don't take a reassembly starting with a First fragment. */
2509 fd = new_fh->next;
2510 if (fd && fd->offset != 0) {
2511 fragment_item *inserted = fd;
2512 bool_Bool multi_insert = (inserted->next != NULL((void*)0));
2513 if (prev_fd) {
2514 prev_fd->next = fd;
2515 } else {
2516 fh->next = fd;
2517 }
2518 for (; fd; fd=fd->next) {
2519 fd->offset += offset;
2520 if (fh->frame < fd->frame) {
2521 fh->frame = fd->frame;
2522 }
2523 }
2524 update_first_gap(fh, inserted, multi_insert);
2525 /* If previously found a Last fragment,
2526 * transfer that info to the new one. */
2527 if (new_fh->flags & FD_DATALEN_SET0x0400) {
2528 fh->flags |= FD_DATALEN_SET0x0400;
2529 fh->datalen = new_fh->datalen + offset;
2530 }
2531 /* Now remove and delete */
2532 new_fh->next = NULL((void*)0);
2533 old_tvb_data = fragment_delete(table, pinfo, id+offset, data);
2534 if (old_tvb_data)
2535 tvb_free(old_tvb_data);
2536 }
2537 }
2538}
2539
2540static fragment_head *
2541fragment_add_seq_single_work(reassembly_table *table, tvbuff_t *tvb,
2542 const int offset, const packet_info *pinfo,
2543 const uint32_t id, const void* data,
2544 const uint32_t frag_data_len,
2545 const bool_Bool first, const bool_Bool last,
2546 const uint32_t max_frags, const uint32_t max_age,
2547 const uint32_t flags)
2548{
2549 reassembled_key reass_key;
2550 tvbuff_t *old_tvb_data;
2551 void *orig_key;
2552 fragment_head *fh, *new_fh;
2553 fragment_item *fd, *prev_fd;
2554 uint32_t frag_number, tmp_offset;
2555 /* Have we already seen this frame?
2556 * If so, look for it in the table of reassembled packets.
2557 * Note here we store in the reassembly table by the single sequence
2558 * number rather than the sequence number of the First fragment. */
2559 if (pinfo->fd->visited) {
2560 reass_key.frame = pinfo->num;
2561 reass_key.id = id;
2562 fh = (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
2563 return fh;
2564 }
2565 /* First let's figure out where we want to add our new fragment */
2566 fh = NULL((void*)0);
2567 if (first) {
2568 frag_number = 0;
2569 fh = lookup_fd_head(table, pinfo, id-frag_number, data, NULL((void*)0));
2570 if ((flags & REASSEMBLE_FLAGS_AGING0x0001) &&
2571 fh && ((fh->frame + max_age) < pinfo->num)) {
2572 old_tvb_data = fragment_delete(table, pinfo, id-frag_number, data);
2573 if (old_tvb_data)
2574 tvb_free(old_tvb_data);
2575 fh = NULL((void*)0);
2576 }
2577 if (fh == NULL((void*)0)) {
2578 /* Not found. Create list-head. */
2579 fh = new_head(FD_BLOCKSEQUENCE0x0100);
2580 insert_fd_head(table, fh, pinfo, id-frag_number, data);
2581 }
2582 /* As this is the first fragment, we might have added segments
2583 * for this reassembly to the previous one in-progress. */
2584 fd = NULL((void*)0);
2585 for (frag_number=1; frag_number < max_frags; frag_number++) {
2586 new_fh = lookup_fd_head(table, pinfo, id-frag_number, data, NULL((void*)0));
2587 if (new_fh != NULL((void*)0)) {
2588 prev_fd = NULL((void*)0);
2589 new_fh->frame = 0;
2590 for (fd=new_fh->next; fd && fd->offset < frag_number; fd=fd->next) {
2591 prev_fd = fd;
2592 if (new_fh->frame < fd->frame) {
2593 new_fh->frame = fd->frame;
2594 }
2595 }
2596 if (prev_fd) {
2597 prev_fd->next = NULL((void*)0);
2598 } else {
2599 new_fh->next = NULL((void*)0);
2600 }
2601 fragment_items_removed(new_fh, prev_fd);
2602 break;
2603 }
2604 }
2605 if (fd != NULL((void*)0)) {
2606 tmp_offset = 0;
2607 for (prev_fd = fd; prev_fd; prev_fd = prev_fd->next) {
2608 prev_fd->offset -= frag_number;
2609 tmp_offset = prev_fd->offset;
2610 if (fh->frame < prev_fd->frame) {
2611 fh->frame = prev_fd->frame;
2612 }
2613 }
2614 MERGE_FRAG(fh, fd);
2615 if (new_fh != NULL((void*)0)) {
2616 /* If we've moved a Last packet, change datalen.
2617 * Second part of this test prob. redundant? */
2618 if (new_fh->flags & FD_DATALEN_SET0x0400 &&
2619 new_fh->datalen >= frag_number) {
2620 fh->flags |= FD_DATALEN_SET0x0400;
2621 fh->datalen = new_fh->datalen - frag_number;
2622 new_fh->flags &= ~FD_DATALEN_SET0x0400;
2623 new_fh->datalen = 0;
2624 }
2625 /* If we've moved all the fragments,
2626 * delete the old head */
2627 if (new_fh->next == NULL((void*)0)) {
2628 old_tvb_data = fragment_delete(table, pinfo, id-frag_number, data);
2629 if (old_tvb_data)
2630 tvb_free(old_tvb_data);
2631 }
2632 } else {
2633 /* Look forward and take off the next (this is
2634 * necessary in some edge cases where max_frags
2635 * prevented some fragments from going on the
2636 * previous First, but they can go on this one. */
2637 fragment_add_seq_single_move(table, pinfo, id,
2638 data, tmp_offset);
2639 }
2640 }
2641 frag_number = 0; /* For the rest of the function */
2642 } else {
2643 for (frag_number=1; frag_number < max_frags; frag_number++) {
2644 fh = lookup_fd_head(table, pinfo, id-frag_number, data, NULL((void*)0));
2645 if ((flags & REASSEMBLE_FLAGS_AGING0x0001) &&
2646 fh && ((fh->frame + max_age) < pinfo->num)) {
2647 old_tvb_data = fragment_delete(table, pinfo, id-frag_number, data);
2648 if (old_tvb_data)
2649 tvb_free(old_tvb_data);
2650 fh = NULL((void*)0);
2651 }
2652 if (fh != NULL((void*)0)) {
2653 if (fh->flags & FD_DATALEN_SET0x0400 &&
2654 fh->datalen < frag_number) {
2655 /* This fragment is after the Last
2656 * fragment, so must go after here. */
2657 fh = NULL((void*)0);
2658 }
2659 break;
2660 }
2661 }
2662 if (fh == NULL((void*)0)) { /* Didn't find location, use default */
2663 frag_number = 1;
2664 /* Already looked for frag_number 1, so just create */
2665 fh = new_head(FD_BLOCKSEQUENCE0x0100);
2666 insert_fd_head(table, fh, pinfo, id-frag_number, data);
2667 }
2668 }
2669 if (last) {
2670 /* Look for fragments past the end set by this Last fragment. */
2671 prev_fd = NULL((void*)0);
2672 for (fd=fh->next; fd && fd->offset <= frag_number; fd=fd->next) {
2673 prev_fd = fd;
2674 }
2675 /* fd is now all fragments offset > frag_number (the Last).
2676 * It shouldn't have a fragment with offset frag_number+1,
2677 * as that would be a First fragment not marked as such.
2678 * However, this can happen if we had unreassembled fragments
2679 * (missing, or at the start of the capture) and we've also
2680 * looped around on the sequence numbers. It can also happen
2681 * if bit errors mess up Last or First. */
2682 if (fd != NULL((void*)0)) {
2683 if (prev_fd) {
2684 prev_fd->next = NULL((void*)0);
2685 } else {
2686 fh->next = NULL((void*)0);
2687 }
2688 fragment_items_removed(fh, prev_fd);
2689 fh->frame = 0;
2690 for (prev_fd=fh->next; prev_fd; prev_fd=prev_fd->next) {
2691 if (fh->frame < prev_fd->frame) {
2692 fh->frame = prev_fd->frame;
2693 }
2694 }
2695 while (fd && fd->offset == frag_number+1) {
2696 /* Definitely have bad data here. Best to
2697 * delete these and leave unreassembled. */
2698 fd = fragment_item_free(fd);
2699 }
2700 }
2701 if (fd != NULL((void*)0)) {
2702 /* Move these onto the next frame. */
2703 new_fh = lookup_fd_head(table, pinfo, id+1, data, NULL((void*)0));
2704 if (new_fh==NULL((void*)0)) {
2705 /* Not found. Create list-head. */
2706 new_fh = new_head(FD_BLOCKSEQUENCE0x0100);
2707 insert_fd_head(table, new_fh, pinfo, id+1, data);
2708 }
2709 tmp_offset = 0;
2710 for (prev_fd = fd; prev_fd; prev_fd = prev_fd->next) {
2711 prev_fd->offset -= (frag_number+1);
2712 tmp_offset = prev_fd->offset;
2713 if (new_fh->frame < fd->frame) {
2714 new_fh->frame = fd->frame;
2715 }
2716 }
2717 MERGE_FRAG(new_fh, fd);
2718 /* If we previously found a different Last fragment,
2719 * transfer that information to the new reassembly. */
2720 if (fh->flags & FD_DATALEN_SET0x0400 &&
2721 fh->datalen > frag_number) {
2722 new_fh->flags |= FD_DATALEN_SET0x0400;
2723 new_fh->datalen = fh->datalen - (frag_number+1);
2724 fh->flags &= ~FD_DATALEN_SET0x0400;
2725 fh->datalen = 0;
2726 } else {
2727 /* Look forward and take off the next (this is
2728 * necessary in some edge cases where max_frags
2729 * prevented some fragments from going on the
2730 * previous First, but they can go on this one. */
2731 fragment_add_seq_single_move(table, pinfo, id+1,
2732 data, tmp_offset);
2733 }
2734 }
2735 } else {
2736 fragment_add_seq_single_move(table, pinfo, id-frag_number, data,
2737 frag_number+1);
2738 }
2739 /* Having cleaned up everything, finally ready to add our new
2740 * fragment. Note that only this will ever complete a reassembly. */
2741 fh = fragment_add_seq_common(table, tvb, offset, pinfo,
2742 id-frag_number, data,
2743 frag_number, frag_data_len,
2744 !last, 0, &orig_key);
2745 if (fh) {
2746 /*
2747 * Reassembly is complete.
2748 *
2749 * If this is in the table of in-progress reassemblies,
2750 * remove it from that table. (It could be that this
2751 * was the first and last fragment, so that no
2752 * reassembly was done.)
2753 */
2754 if (orig_key != NULL((void*)0))
2755 fragment_unhash(table, orig_key);
2756
2757 /*
2758 * Add this item to the table of reassembled packets.
2759 */
2760 fragment_reassembled_single(table, fh, pinfo, id-frag_number);
2761 return fh;
2762 } else {
2763 /*
2764 * Reassembly isn't complete.
2765 */
2766 return NULL((void*)0);
2767 }
2768}
2769
2770fragment_head *
2771fragment_add_seq_single(reassembly_table *table, tvbuff_t *tvb,
2772 const int offset, const packet_info *pinfo,
2773 const uint32_t id, const void* data,
2774 const uint32_t frag_data_len,
2775 const bool_Bool first, const bool_Bool last,
2776 const uint32_t max_frags)
2777{
2778 return fragment_add_seq_single_work(table, tvb, offset, pinfo,
2779 id, data, frag_data_len,
2780 first, last, max_frags, 0, 0);
2781}
2782
2783fragment_head *
2784fragment_add_seq_single_aging(reassembly_table *table, tvbuff_t *tvb,
2785 const int offset, const packet_info *pinfo,
2786 const uint32_t id, const void* data,
2787 const uint32_t frag_data_len,
2788 const bool_Bool first, const bool_Bool last,
2789 const uint32_t max_frags, const uint32_t max_age)
2790{
2791 return fragment_add_seq_single_work(table, tvb, offset, pinfo,
2792 id, data, frag_data_len,
2793 first, last, max_frags, max_age,
2794 REASSEMBLE_FLAGS_AGING0x0001);
2795}
2796
2797void
2798fragment_start_seq_check(reassembly_table *table, const packet_info *pinfo,
2799 const uint32_t id, const void *data,
2800 const uint32_t tot_len)
2801{
2802 fragment_head *fd_head;
2803
2804 /* Have we already seen this frame ?*/
2805 if (pinfo->fd->visited) {
2806 return;
2807 }
2808
2809 /* Check if fragment data exists */
2810 fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0));
2811
2812 if (fd_head == NULL((void*)0)) {
2813 /* Create list-head. */
2814 fd_head = new_head(FD_BLOCKSEQUENCE0x0100|FD_DATALEN_SET0x0400);
2815 fd_head->datalen = tot_len;
2816
2817 insert_fd_head(table, fd_head, pinfo, id, data);
2818 }
2819}
2820
2821fragment_head *
2822fragment_end_seq_next(reassembly_table *table, const packet_info *pinfo,
2823 const uint32_t id, const void *data)
2824{
2825 reassembled_key reass_key;
2826 reassembled_key *new_key;
2827 fragment_head *fd_head;
2828 fragment_item *fd;
2829 void *orig_key;
2830 uint32_t max_offset = 0;
2831
2832 /*
2833 * Have we already seen this frame?
2834 * If so, look for it in the table of reassembled packets.
2835 */
2836 if (pinfo->fd->visited) {
2837 reass_key.frame = pinfo->num;
2838 reass_key.id = id;
2839 return (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key);
2840 }
2841
2842 fd_head = lookup_fd_head(table, pinfo, id, data, &orig_key);
2843
2844 if (fd_head) {
2845 for (fd = fd_head->next; fd; fd = fd->next) {
2846 if (fd->offset > max_offset) {
2847 max_offset = fd->offset;
2848 }
2849 }
2850 fd_head->datalen = max_offset;
2851 fd_head->flags |= FD_DATALEN_SET0x0400;
2852
2853 fragment_defragment_and_free (fd_head, pinfo);
2854
2855 /*
2856 * Remove this from the table of in-progress reassemblies,
2857 * and free up any memory used for it in that table.
2858 */
2859 fragment_unhash(table, orig_key);
2860
2861 /*
2862 * Add this item to the table of reassembled packets.
2863 */
2864 fragment_reassembled(table, fd_head, pinfo, id);
2865 if (fd_head->next != NULL((void*)0)) {
2866 new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc ((sizeof (reassembled_key) >
0 ? sizeof (reassembled_key) : 1)))
;
2867 new_key->frame = pinfo->num;
2868 new_key->id = id;
2869 reassembled_table_insert(table->reassembled_table, new_key, fd_head);
2870 }
2871
2872 return fd_head;
2873 } else {
2874 /*
2875 * Fragment data not found.
2876 */
2877 return NULL((void*)0);
2878 }
2879}
2880
2881/*
2882 * Process reassembled data; if we're on the frame in which the data
2883 * was reassembled, put the fragment information into the protocol
2884 * tree, and construct a tvbuff with the reassembled data, otherwise
2885 * just put a "reassembled in" item into the protocol tree.
2886 * offset from start of tvb, result up to end of tvb
2887 */
2888tvbuff_t *
2889process_reassembled_data(tvbuff_t *tvb, const int offset, packet_info *pinfo,
2890 const char *name, fragment_head *fd_head, const fragment_items *fit,
2891 bool_Bool *update_col_infop, proto_tree *tree)
2892{
2893 tvbuff_t *next_tvb;
2894 bool_Bool update_col_info;
2895 proto_item *frag_tree_item;
2896
2897 if (fd_head != NULL((void*)0) && pinfo->num == fd_head->reassembled_in && pinfo->curr_layer_num == fd_head->reas_in_layer_num) {
2898 /*
2899 * OK, we've reassembled this.
2900 * Is this something that's been reassembled from more
2901 * than one fragment?
2902 */
2903 if (fd_head->next != NULL((void*)0)) {
2904 /*
2905 * Yes.
2906 * Allocate a new tvbuff, referring to the
2907 * reassembled payload, and set
2908 * the tvbuff to the list of tvbuffs to which
2909 * the tvbuff we were handed refers, so it'll get
2910 * cleaned up when that tvbuff is cleaned up.
2911 */
2912 next_tvb = tvb_new_chain(tvb, fd_head->tvb_data);
2913
2914 /* Add the defragmented data to the data source list. */
2915 add_new_data_source(pinfo, next_tvb, name);
2916
2917 /* show all fragments */
2918 if (fd_head->flags & FD_BLOCKSEQUENCE0x0100) {
2919 update_col_info = !show_fragment_seq_tree(
2920 fd_head, fit, tree, pinfo, next_tvb, &frag_tree_item);
2921 } else {
2922 update_col_info = !show_fragment_tree(fd_head,
2923 fit, tree, pinfo, next_tvb, &frag_tree_item);
2924 }
2925 } else {
2926 /*
2927 * No.
2928 * Return a tvbuff with the payload, a subset of the
2929 * tvbuff passed in. (The dissector SHOULD pass in
2930 * the correct tvbuff and offset.)
2931 */
2932 int len;
2933 /* For FD_BLOCKSEQUENCE, len is the length in bytes,
2934 * datalen is the number of fragments.
2935 */
2936 if (fd_head->flags & FD_BLOCKSEQUENCE0x0100) {
2937 len = fd_head->len;
2938 } else {
2939 len = fd_head->datalen;
2940 }
2941 next_tvb = tvb_new_subset_length(tvb, offset, len);
2942 pinfo->fragmented = false0; /* one-fragment packet */
2943 update_col_info = true1;
2944 }
2945 if (update_col_infop != NULL((void*)0))
2946 *update_col_infop = update_col_info;
2947 } else {
2948 /*
2949 * We don't have the complete reassembled payload, or this
2950 * isn't the final frame of that payload.
2951 */
2952 next_tvb = NULL((void*)0);
2953
2954 /*
2955 * If we know what frame this was reassembled in,
2956 * and if there's a field to use for the number of
2957 * the frame in which the packet was reassembled,
2958 * add it to the protocol tree.
2959 */
2960 if (fd_head != NULL((void*)0) && fit->hf_reassembled_in != NULL((void*)0)) {
2961 proto_item *fei = proto_tree_add_uint(tree,
2962 *(fit->hf_reassembled_in), tvb,
2963 0, 0, fd_head->reassembled_in);
2964 proto_item_set_generated(fei);
2965 }
2966 }
2967 return next_tvb;
2968}
2969
2970/*
2971 * Show a single fragment in a fragment subtree, and put information about
2972 * it in the top-level item for that subtree.
2973 */
2974static void
2975show_fragment(fragment_item *fd, const int offset, const fragment_items *fit,
2976 proto_tree *ft, proto_item *fi, const bool_Bool first_frag,
2977 const uint32_t count, tvbuff_t *tvb, packet_info *pinfo)
2978{
2979 proto_item *fei=NULL((void*)0);
2980 int hf;
2981
2982 if (first_frag) {
2983 char *name;
2984 if (count == 1) {
2985 name = g_strdup(proto_registrar_get_name(*(fit->hf_fragment)))g_strdup_inline (proto_registrar_get_name(*(fit->hf_fragment
)))
;
2986 } else {
2987 name = g_strdup(proto_registrar_get_name(*(fit->hf_fragments)))g_strdup_inline (proto_registrar_get_name(*(fit->hf_fragments
)))
;
2988 }
2989 proto_item_set_text(fi, "%u %s (%u byte%s): ", count, name, tvb_captured_length(tvb),
2990 plurality(tvb_captured_length(tvb), "", "s")((tvb_captured_length(tvb)) == 1 ? ("") : ("s")));
2991 g_free(name)(__builtin_object_size ((name), 0) != ((size_t) - 1)) ? g_free_sized
(name, __builtin_object_size ((name), 0)) : (g_free) (name)
;
2992 } else {
2993 proto_item_append_text(fi, ", ");
2994 }
2995 proto_item_append_text(fi, "#%u(%u)", fd->frame, fd->len);
2996
2997 if (fd->flags & (FD_OVERLAPCONFLICT0x0004
2998 |FD_MULTIPLETAILS0x0008|FD_TOOLONGFRAGMENT0x0010) ) {
2999 hf = *(fit->hf_fragment_error);
3000 } else {
3001 hf = *(fit->hf_fragment);
3002 }
3003 if (fd->len == 0) {
3004 fei = proto_tree_add_uint_format(ft, hf,
3005 tvb, offset, fd->len,
3006 fd->frame,
3007 "Frame: %u (no data)",
3008 fd->frame);
3009 } else {
3010 fei = proto_tree_add_uint_format(ft, hf,
3011 tvb, offset, fd->len,
3012 fd->frame,
3013 "Frame: %u, payload: %u-%u (%u byte%s)",
3014 fd->frame,
3015 offset,
3016 offset+fd->len-1,
3017 fd->len,
3018 plurality(fd->len, "", "s")((fd->len) == 1 ? ("") : ("s")));
3019 }
3020 proto_item_set_generated(fei);
3021 mark_frame_as_depended_upon(pinfo->fd, fd->frame);
3022 if (fd->flags & (FD_OVERLAP0x0002|FD_OVERLAPCONFLICT0x0004
3023 |FD_MULTIPLETAILS0x0008|FD_TOOLONGFRAGMENT0x0010) ) {
3024 /* this fragment has some flags set, create a subtree
3025 * for it and display the flags.
3026 */
3027 proto_tree *fet=NULL((void*)0);
3028
3029 fet = proto_item_add_subtree(fei, *(fit->ett_fragment));
3030 if (fd->flags&FD_OVERLAP0x0002) {
3031 fei=proto_tree_add_boolean(fet,
3032 *(fit->hf_fragment_overlap),
3033 tvb, 0, 0,
3034 true1);
3035 proto_item_set_generated(fei);
3036 }
3037 if (fd->flags&FD_OVERLAPCONFLICT0x0004) {
3038 fei=proto_tree_add_boolean(fet,
3039 *(fit->hf_fragment_overlap_conflict),
3040 tvb, 0, 0,
3041 true1);
3042 proto_item_set_generated(fei);
3043 }
3044 if (fd->flags&FD_MULTIPLETAILS0x0008) {
3045 fei=proto_tree_add_boolean(fet,
3046 *(fit->hf_fragment_multiple_tails),
3047 tvb, 0, 0,
3048 true1);
3049 proto_item_set_generated(fei);
3050 }
3051 if (fd->flags&FD_TOOLONGFRAGMENT0x0010) {
3052 fei=proto_tree_add_boolean(fet,
3053 *(fit->hf_fragment_too_long_fragment),
3054 tvb, 0, 0,
3055 true1);
3056 proto_item_set_generated(fei);
3057 }
3058 }
3059}
3060
3061static bool_Bool
3062show_fragment_errs_in_col(fragment_head *fd_head, const fragment_items *fit,
3063 packet_info *pinfo)
3064{
3065 if (fd_head->flags & (FD_OVERLAPCONFLICT0x0004
3066 |FD_MULTIPLETAILS0x0008|FD_TOOLONGFRAGMENT0x0010) ) {
3067 col_add_fstr(pinfo->cinfo, COL_INFO, "[Illegal %s]", fit->tag);
3068 return true1;
3069 }
3070
3071 return false0;
3072}
3073
3074/* This function will build the fragment subtree; it's for fragments
3075 reassembled with "fragment_add()".
3076
3077 It will return true if there were fragmentation errors
3078 or false if fragmentation was ok.
3079*/
3080bool_Bool
3081show_fragment_tree(fragment_head *fd_head, const fragment_items *fit,
3082 proto_tree *tree, packet_info *pinfo, tvbuff_t *tvb, proto_item **fi)
3083{
3084 fragment_item *fd;
3085 proto_tree *ft;
3086 bool_Bool first_frag;
3087 uint32_t count = 0;
3088 /* It's not fragmented. */
3089 pinfo->fragmented = false0;
3090
3091 *fi = proto_tree_add_item(tree, *(fit->hf_fragments), tvb, 0, -1, ENC_NA0x00000000);
3092 proto_item_set_generated(*fi);
3093
3094 ft = proto_item_add_subtree(*fi, *(fit->ett_fragments));
3095 first_frag = true1;
3096 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next) {
3097 count++;
3098 }
3099 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next) {
3100 show_fragment(fd, fd->offset, fit, ft, *fi, first_frag, count, tvb, pinfo);
3101 first_frag = false0;
3102 }
3103
3104 if (fit->hf_fragment_count) {
3105 proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_fragment_count),
3106 tvb, 0, 0, count);
3107 proto_item_set_generated(fli);
3108 }
3109
3110 if (fit->hf_reassembled_length) {
3111 proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_reassembled_length),
3112 tvb, 0, 0, tvb_captured_length (tvb));
3113 proto_item_set_generated(fli);
3114 }
3115
3116 if (fit->hf_reassembled_data) {
3117 proto_item *fli = proto_tree_add_item(ft, *(fit->hf_reassembled_data),
3118 tvb, 0, tvb_captured_length(tvb), ENC_NA0x00000000);
3119 proto_item_set_generated(fli);
3120 }
3121
3122 return show_fragment_errs_in_col(fd_head, fit, pinfo);
3123}
3124
3125/* This function will build the fragment subtree; it's for fragments
3126 reassembled with "fragment_add_seq()" or "fragment_add_seq_check()".
3127
3128 It will return true if there were fragmentation errors
3129 or false if fragmentation was ok.
3130*/
3131bool_Bool
3132show_fragment_seq_tree(fragment_head *fd_head, const fragment_items *fit,
3133 proto_tree *tree, packet_info *pinfo, tvbuff_t *tvb, proto_item **fi)
3134{
3135 uint32_t offset, next_offset, count = 0;
3136 fragment_item *fd, *last_fd;
3137 proto_tree *ft;
3138 bool_Bool first_frag;
3139
3140 /* It's not fragmented. */
3141 pinfo->fragmented = false0;
3142
3143 *fi = proto_tree_add_item(tree, *(fit->hf_fragments), tvb, 0, -1, ENC_NA0x00000000);
3144 proto_item_set_generated(*fi);
3145
3146 ft = proto_item_add_subtree(*fi, *(fit->ett_fragments));
3147 offset = 0;
3148 next_offset = 0;
3149 last_fd = NULL((void*)0);
3150 first_frag = true1;
3151 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next){
3152 count++;
3153 }
3154 for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next){
3155 if (last_fd == NULL((void*)0) || last_fd->offset != fd->offset) {
3156 offset = next_offset;
3157 next_offset += fd->len;
3158 }
3159 last_fd = fd;
3160 show_fragment(fd, offset, fit, ft, *fi, first_frag, count, tvb, pinfo);
3161 first_frag = false0;
3162 }
3163
3164 if (fit->hf_fragment_count) {
3165 proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_fragment_count),
3166 tvb, 0, 0, count);
3167 proto_item_set_generated(fli);
3168 }
3169
3170 if (fit->hf_reassembled_length) {
3171 proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_reassembled_length),
3172 tvb, 0, 0, tvb_captured_length (tvb));
3173 proto_item_set_generated(fli);
3174 }
3175
3176 if (fit->hf_reassembled_data) {
3177 proto_item *fli = proto_tree_add_item(ft, *(fit->hf_reassembled_data),
3178 tvb, 0, tvb_captured_length(tvb), ENC_NA0x00000000);
3179 proto_item_set_generated(fli);
3180 }
3181
3182 return show_fragment_errs_in_col(fd_head, fit, pinfo);
3183}
3184
3185static void
3186reassembly_table_init_reg_table(void *p, void *user_data _U___attribute__((unused)))
3187{
3188 register_reassembly_table_t* reg_table = (register_reassembly_table_t*)p;
3189 reassembly_table_init(reg_table->table, reg_table->funcs);
3190}
3191
3192static void
3193reassembly_table_init_reg_tables(void)
3194{
3195 g_list_foreach(reassembly_table_list, reassembly_table_init_reg_table, NULL((void*)0));
3196}
3197
3198static void
3199reassembly_table_cleanup_reg_table(void *p, void *user_data _U___attribute__((unused)))
3200{
3201 register_reassembly_table_t* reg_table = (register_reassembly_table_t*)p;
3202 reassembly_table_destroy(reg_table->table);
3203}
3204
3205static void
3206reassembly_table_cleanup_reg_tables(void)
3207{
3208 g_list_foreach(reassembly_table_list, reassembly_table_cleanup_reg_table, NULL((void*)0));
3209}
3210
3211void reassembly_tables_init(void)
3212{
3213 register_init_routine(&reassembly_table_init_reg_tables);
3214 register_cleanup_routine(&reassembly_table_cleanup_reg_tables);
3215}
3216
3217static void
3218reassembly_table_free(void *p, void *user_data _U___attribute__((unused)))
3219{
3220 register_reassembly_table_t* reg_table = (register_reassembly_table_t*)p;
3221 reassembly_table_destroy(reg_table->table);
3222 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)
;
3223}
3224
3225void
3226reassembly_table_cleanup(void)
3227{
3228 g_list_foreach(reassembly_table_list, reassembly_table_free, NULL((void*)0));
3229 g_list_free(reassembly_table_list);
3230}
3231
3232/* One instance of this structure is created for each pdu that spans across
3233 * multiple segments. (MSP) */
3234typedef struct _multisegment_pdu_t {
3235 uint64_t first_frame;
3236 uint64_t last_frame;
3237 unsigned start_offset_at_first_frame;
3238 unsigned end_offset_at_last_frame;
3239 int length; /* length of this MSP */
3240 uint32_t streaming_reassembly_id;
3241 /* pointer to previous multisegment_pdu */
3242 struct _multisegment_pdu_t* prev_msp;
3243} multisegment_pdu_t;
3244
3245/* struct for keeping the reassembly information of each stream */
3246struct streaming_reassembly_info_t {
3247 /* This map is keyed by frame num and keeps track of all MSPs for this
3248 * stream. Different frames will point to the same MSP if they contain
3249 * part data of this MSP. If a frame contains data that
3250 * belongs to two MSPs, it will point to the second MSP. */
3251 wmem_map_t* multisegment_pdus;
3252 /* This map is keyed by frame num and keeps track of the frag_offset
3253 * of the first byte of frames for fragment_add() after first scan. */
3254 wmem_map_t* frame_num_frag_offset_map;
3255 /* how many bytes the current uncompleted MSP still needs. (only valid for first scan) */
3256 int prev_deseg_len;
3257 /* the current uncompleted MSP (only valid for first scan) */
3258 multisegment_pdu_t* last_msp;
3259};
3260
3261static uint32_t
3262create_streaming_reassembly_id(void)
3263{
3264 static uint32_t global_streaming_reassembly_id = 0;
3265 return ++global_streaming_reassembly_id;
3266}
3267
3268streaming_reassembly_info_t*
3269streaming_reassembly_info_new(void)
3270{
3271 return wmem_new0(wmem_file_scope(), streaming_reassembly_info_t)((streaming_reassembly_info_t*)wmem_alloc0((wmem_file_scope()
), sizeof(streaming_reassembly_info_t)))
;
3272}
3273
3274/* Following is an example of ProtoA and ProtoB protocols from the declaration of this function in 'reassemble.h':
3275 *
3276 * +------------------ A Multisegment PDU of ProtoB ----------------------+
3277 * | |
3278 * +--- ProtoA payload1 ---+ +- payload2 -+ +- Payload3 -+ +- Payload4 -+ +- ProtoA payload5 -+
3279 * | EoMSP | OmNFP | BoMSP | | MoMSP | | MoMSP | | MoMSP | | EoMSP | BoMSP |
3280 * +-------+-------+-------+ +------------+ +------------+ +------------+ +---------+---------+
3281 * | |
3282 * +----------------------------------------------------------------------+
3283 *
3284 * For a ProtoA payload composed of EoMSP + OmNFP + BoMSP will call fragment_add() twice on EoMSP and BoMSP; and call
3285 * process_reassembled_data() once for generating tvb of a MSP to which EoMSP belongs; and call subdissector twice on
3286 * reassembled MSP of EoMSP and OmNFP + BoMSP. After that finds BoMSP is a beginning of a MSP at first scan.
3287 *
3288 * The rules are:
3289 *
3290 * - If a ProtoA payload contains EoMSP, we will need call fragment_add(), process_reassembled_data() and subdissector
3291 * once on it to end a MSP. (May run twice or more times at first scan, because subdissector may only return the
3292 * head length of message by pinfo->desegment_len. We need run second time for subdissector to determine the length
3293 * of entire message).
3294 *
3295 * - If a ProtoA payload contains OmNFP, we will need only call subdissector once on it. The subdissector need dissect
3296 * all non-fragment PDUs in it. (no desegment_len should output)
3297 *
3298 * - If a ProtoA payload contains BoMSP, we will need call subdissector once on BoMSP or OmNFP+BoMSP (because unknown
3299 * during first scan). The subdissector will output desegment_len (!= 0). Then we will call fragment_add()
3300 * with a new reassembly id on BoMSP for starting a new MSP.
3301 *
3302 * - If a ProtoA payload only contains MoMSP (entire payload is part of a MSP), we will only call fragment_add() once
3303 * or twice (at first scan) on it. The subdissector will not be called.
3304 *
3305 * In this implementation, only multisegment PDUs are recorded in multisegment_pdus map keyed by the numbers (uint64_t)
3306 * of frames belongs to MSPs. Each MSP in the map has a pointer referred to previous MSP, because we may need
3307 * two MSPs to dissect a ProtoA payload that contains EoMSP + BoMSP at the same time. The multisegment_pdus map is built
3308 * during first scan (pinfo->visited == false) with help of prev_deseg_len and last_msp fields of streaming_reassembly_info_t
3309 * for each direction of a ProtoA STREAM. The prev_deseg_len record how many bytes of subsequent ProtoA payloads belong to
3310 * previous PDU during first scan. The last_msp member of streaming_reassembly_info_t is always point to last MSP which
3311 * is created during scan previous or early ProtoA payloads. Since subdissector might return only the head length of entire
3312 * message (by pinfo->desegment_len) when there is not enough data to determine the message length, we need to reopen
3313 * reassembly fragments for adding more bytes during scanning the next ProtoA payload. We have to use fragment_add()
3314 * instead of fragment_add_check() or fragment_add_seq_next().
3315 *
3316 * Read more: please refer to comments of the declaration of this function in 'reassemble.h'.
3317 */
3318int
3319reassemble_streaming_data_and_call_subdissector(
3320 tvbuff_t* tvb, packet_info* pinfo, unsigned offset, int length,
3321 proto_tree* segment_tree, proto_tree* reassembled_tree, reassembly_table streaming_reassembly_table,
3322 streaming_reassembly_info_t* reassembly_info, uint64_t cur_frame_num,
3323 dissector_handle_t subdissector_handle, proto_tree* subdissector_tree, void* subdissector_data,
3324 const char* label, const fragment_items* frag_hf_items, int hf_segment_data
3325)
3326{
3327 int orig_length = length;
3328 int datalen = 0;
3329 int bytes_belong_to_prev_msp = 0; /* bytes belong to previous MSP */
3330 uint32_t reassembly_id = 0, frag_offset = 0;
3331 fragment_head* head = NULL((void*)0);
3332 bool_Bool need_more = false0;
3333 bool_Bool found_BoMSP = false0;
3334 multisegment_pdu_t* cur_msp = NULL((void*)0), * prev_msp = NULL((void*)0);
3335 uint16_t save_can_desegment;
3336 int save_desegment_offset;
3337 uint32_t save_desegment_len;
3338 uint64_t* frame_ptr;
3339
3340 save_can_desegment = pinfo->can_desegment;
3341 save_desegment_offset = pinfo->desegment_offset;
3342 save_desegment_len = pinfo->desegment_len;
3343
3344 /* calculate how many bytes of this payload belongs to previous MSP (EoMSP) */
3345 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3346 /* this is first scan */
3347 if (reassembly_info->prev_deseg_len == DESEGMENT_ONE_MORE_SEGMENT0x0fffffff) {
3348 /* assuming the entire tvb belongs to the previous MSP */
3349 bytes_belong_to_prev_msp = length;
3350 reassembly_info->prev_deseg_len = length;
3351 } else if (reassembly_info->prev_deseg_len > 0) {
3352 /* part or all of current payload belong to previous MSP */
3353 bytes_belong_to_prev_msp = MIN(reassembly_info->prev_deseg_len, length)(((reassembly_info->prev_deseg_len) < (length)) ? (reassembly_info
->prev_deseg_len) : (length))
;
3354 reassembly_info->prev_deseg_len -= bytes_belong_to_prev_msp;
3355 need_more = (reassembly_info->prev_deseg_len > 0);
3356 } /* else { beginning of a new PDU (might be a NFP or MSP) } */
3357
3358 if (bytes_belong_to_prev_msp > 0) {
3359 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", 3359, "reassembly_info->last_msp != ((void*)0)"
))))
;
3360 reassembly_id = reassembly_info->last_msp->streaming_reassembly_id;
3361 frag_offset = reassembly_info->last_msp->length;
3362 if (reassembly_info->frame_num_frag_offset_map == NULL((void*)0)) {
3363 reassembly_info->frame_num_frag_offset_map = wmem_map_new(wmem_file_scope(), g_int64_hash, g_int64_equal);
3364 }
3365 frame_ptr = (uint64_t*)wmem_memdup(wmem_file_scope(), &cur_frame_num, sizeof(uint64_t));
3366 wmem_map_insert(reassembly_info->frame_num_frag_offset_map, frame_ptr, GUINT_TO_POINTER(frag_offset)((gpointer) (gulong) (frag_offset)));
3367 /* This payload contains the data of previous msp, so we point to it. That may be overridden late. */
3368 wmem_map_insert(reassembly_info->multisegment_pdus, frame_ptr, reassembly_info->last_msp);
3369 }
3370 } else {
3371 /* not first scan, use information of multisegment_pdus built during first scan */
3372 if (reassembly_info->multisegment_pdus) {
3373 cur_msp = (multisegment_pdu_t*)wmem_map_lookup(reassembly_info->multisegment_pdus, &cur_frame_num);
3374 }
3375 if (cur_msp) {
3376 if (cur_msp->first_frame == cur_frame_num) {
3377 /* Current payload contains a beginning of a MSP. (BoMSP)
3378 * The cur_msp contains information about the beginning MSP.
3379 * If prev_msp is not null, that means this payload also contains
3380 * the last part of previous MSP. (EoMSP) */
3381 prev_msp = cur_msp->prev_msp;
3382 } else {
3383 /* Current payload is not a first frame of a MSP (not include BoMSP). */
3384 prev_msp = cur_msp;
3385 cur_msp = NULL((void*)0);
3386 }
3387 }
3388
3389 if (prev_msp && prev_msp->last_frame >= cur_frame_num) {
3390 if (prev_msp->last_frame == cur_frame_num) {
3391 /* this payload contains part of previous MSP (contains EoMSP) */
3392 bytes_belong_to_prev_msp = prev_msp->end_offset_at_last_frame - offset;
3393 } else { /* if (prev_msp->last_frame > cur_frame_num) */
3394 /* this payload all belongs to previous MSP */
3395 bytes_belong_to_prev_msp = length;
3396 need_more = true1;
3397 }
3398 reassembly_id = prev_msp->streaming_reassembly_id;
3399 }
3400 if (reassembly_info->frame_num_frag_offset_map) {
3401 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)))
;
3402 }
3403 }
3404
3405 /* handling EoMSP or MoMSP (entire payload being middle part of a MSP) */
3406 while (bytes_belong_to_prev_msp > 0) {
3407 tvbuff_t* reassembled_tvb = NULL((void*)0);
3408 DISSECTOR_ASSERT(reassembly_id > 0)((void) ((reassembly_id > 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3408,
"reassembly_id > 0"))))
;
3409 pinfo->can_desegment = 2; /* this will be decreased one while passing to subdissector */
3410 pinfo->desegment_offset = 0;
3411 pinfo->desegment_len = 0;
3412
3413 head = fragment_add(&streaming_reassembly_table, tvb, offset, pinfo, reassembly_id, NULL((void*)0),
3414 frag_offset, bytes_belong_to_prev_msp, need_more);
3415
3416 if (head) {
3417 if (frag_hf_items->hf_reassembled_in) {
3418 proto_item_set_generated(
3419 proto_tree_add_uint(segment_tree, *(frag_hf_items->hf_reassembled_in), tvb, offset,
3420 bytes_belong_to_prev_msp, head->reassembled_in)
3421 );
3422 }
3423
3424 if (!need_more) {
3425 reassembled_tvb = process_reassembled_data(tvb, offset, pinfo,
3426 wmem_strdup_printf(pinfo->pool, "Reassembled %s", label),
3427 head, frag_hf_items, NULL((void*)0), reassembled_tree);
3428 }
3429 }
3430
3431 proto_tree_add_bytes_format(segment_tree, hf_segment_data, tvb, offset,
3432 bytes_belong_to_prev_msp, NULL((void*)0), "%s Segment data (%u byte%s)", label,
3433 bytes_belong_to_prev_msp, plurality(bytes_belong_to_prev_msp, "", "s")((bytes_belong_to_prev_msp) == 1 ? ("") : ("s")));
3434
3435 if (reassembled_tvb) {
3436 /* normally, this stage will dissect one or more completed pdus */
3437 /* Note, don't call_dissector_with_data because sometime the pinfo->curr_layer_num will changed
3438 * after calling that will make reassembly failed! */
3439 call_dissector_only(subdissector_handle, reassembled_tvb, pinfo, subdissector_tree, subdissector_data);
3440 }
3441
3442 if (pinfo->desegment_len) {
3443 /* that must only happen during first scan the reassembly_info->prev_deseg_len might be only the
3444 * head length of entire message. */
3445 DISSECTOR_ASSERT(!PINFO_FD_VISITED(pinfo))((void) ((!((pinfo)->fd->visited)) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3445,
"!((pinfo)->fd->visited)"))))
;
3446 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", 3448, "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."
))))
3447 "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", 3448, "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."
))))
3448 " 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", 3448, "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."
))))
;
3449
3450 if (pinfo->desegment_offset > 0) {
3451 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", 3455, "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
)))))
3452 && 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", 3455, "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
)))))
3453 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", 3455, "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
)))))
3454 "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", 3455, "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
)))))
3455 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", 3455, "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
)))))
;
3456
3457 /* shorten the bytes_belong_to_prev_msp and just truncate the reassembled tvb */
3458 bytes_belong_to_prev_msp = pinfo->desegment_offset - reassembly_info->last_msp->length;
3459 fragment_truncate(&streaming_reassembly_table, pinfo, reassembly_id, NULL((void*)0), pinfo->desegment_offset);
3460 found_BoMSP = true1;
3461 } else {
3462 if (pinfo->desegment_len == DESEGMENT_ONE_MORE_SEGMENT0x0fffffff) {
3463 /* just need more bytes, all remaining bytes belongs to previous MSP (to run fragment_add again) */
3464 bytes_belong_to_prev_msp = length;
3465 }
3466
3467 /* Remove the data added by previous fragment_add(), and reopen fragments for adding more bytes. */
3468 fragment_truncate(&streaming_reassembly_table, pinfo, reassembly_id, NULL((void*)0), reassembly_info->last_msp->length);
3469 fragment_set_partial_reassembly(&streaming_reassembly_table, pinfo, reassembly_id, NULL((void*)0));
3470
3471 reassembly_info->prev_deseg_len = bytes_belong_to_prev_msp + pinfo->desegment_len;
3472 bytes_belong_to_prev_msp = MIN(reassembly_info->prev_deseg_len, length)(((reassembly_info->prev_deseg_len) < (length)) ? (reassembly_info
->prev_deseg_len) : (length))
;
3473 reassembly_info->prev_deseg_len -= bytes_belong_to_prev_msp;
3474 need_more = (reassembly_info->prev_deseg_len > 0);
3475 continue;
3476 }
3477 }
3478
3479 if (pinfo->desegment_len == 0 || found_BoMSP) {
3480 /* We will arrive here, only when the MSP is defragmented and dissected or this
3481 * payload all belongs to previous MSP (only fragment_add() with need_more=true called)
3482 * or BoMSP is parsed while pinfo->desegment_offset > 0 and pinfo->desegment_len != 0
3483 */
3484 offset += bytes_belong_to_prev_msp;
3485 length -= bytes_belong_to_prev_msp;
3486 DISSECTOR_ASSERT(length >= 0)((void) ((length >= 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3486,
"length >= 0"))))
;
3487 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3488 reassembly_info->last_msp->length += bytes_belong_to_prev_msp;
3489 }
3490
3491 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited) && reassembled_tvb) {
3492 /* completed current msp */
3493 reassembly_info->last_msp->last_frame = cur_frame_num;
3494 reassembly_info->last_msp->end_offset_at_last_frame = offset;
3495 reassembly_info->prev_deseg_len = pinfo->desegment_len;
3496 }
3497 bytes_belong_to_prev_msp = 0; /* break */
3498 }
3499 }
3500
3501 /* to find and handle OmNFP, and find BoMSP at first scan. */
3502 if (length > 0 && !found_BoMSP) {
3503 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3504 /* It is first scan, to dissect remaining bytes to find whether it is OmNFP only, or BoMSP only or OmNFP + BoMSP. */
3505 datalen = length;
3506 DISSECTOR_ASSERT(cur_msp == NULL)((void) ((cur_msp == ((void*)0)) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3506,
"cur_msp == ((void*)0)"))))
;
3507 } else {
3508 /* Not first scan */
3509 if (cur_msp) {
3510 /* There's a BoMSP. Let's calculate the length of OmNFP between EoMSP and BoMSP */
3511 datalen = cur_msp->start_offset_at_first_frame - offset; /* if result is zero that means no OmNFP */
3512 } else {
3513 /* This payload is not a beginning of MSP. The remaining bytes all belong to OmNFP without BoMSP */
3514 datalen = length;
3515 }
3516 }
3517 DISSECTOR_ASSERT(datalen >= 0)((void) ((datalen >= 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3517,
"datalen >= 0"))))
;
3518
3519 /* Dissect the remaining of this payload. If (datalen == 0) means remaining only have one BoMSP without OmNFP. */
3520 if (datalen > 0) {
3521 /* we dissect if it is not dissected before or it is a non-fragment pdu (between two multisegment pdus) */
3522 pinfo->can_desegment = 2;
3523 pinfo->desegment_offset = 0;
3524 pinfo->desegment_len = 0;
3525
3526 call_dissector_only(subdissector_handle, tvb_new_subset_length(tvb, offset, datalen),
3527 pinfo, subdissector_tree, subdissector_data);
3528
3529 if (pinfo->desegment_len) {
3530 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", 3532, "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."
))))
3531 "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", 3532, "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."
))))
3532 " 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", 3532, "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."
))))
;
3533 /* only happen during first scan */
3534 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", 3534, "!((pinfo)->fd->visited) && datalen == length"
))))
;
3535 offset += pinfo->desegment_offset;
3536 length -= pinfo->desegment_offset;
3537 } else {
3538 /* all remaining bytes are consumed by subdissector */
3539 offset += datalen;
3540 length -= datalen;
3541 }
3542 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3543 reassembly_info->prev_deseg_len = pinfo->desegment_len;
3544 }
3545 } /* else all remaining bytes (BoMSP) belong to a new MSP */
3546 DISSECTOR_ASSERT(length >= 0)((void) ((length >= 0) ? (void)0 : (proto_report_dissector_bug
("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3546,
"length >= 0"))))
;
3547 }
3548
3549 /* handling BoMSP */
3550 if (length > 0) {
3551 col_append_sep_fstr(pinfo->cinfo, COL_INFO, " ", "[%s segment of a reassembled PDU] ", label);
3552 if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) {
3553 /* create a msp for current frame during first scan */
3554 cur_msp = wmem_new0(wmem_file_scope(), multisegment_pdu_t)((multisegment_pdu_t*)wmem_alloc0((wmem_file_scope()), sizeof
(multisegment_pdu_t)))
;
3555 cur_msp->first_frame = cur_frame_num;
3556 cur_msp->last_frame = UINT64_MAX(18446744073709551615UL);
3557 cur_msp->start_offset_at_first_frame = offset;
3558 cur_msp->length = length;
3559 cur_msp->streaming_reassembly_id = reassembly_id = create_streaming_reassembly_id();
3560 cur_msp->prev_msp = reassembly_info->last_msp;
3561 reassembly_info->last_msp = cur_msp;
3562 if (reassembly_info->multisegment_pdus == NULL((void*)0)) {
3563 reassembly_info->multisegment_pdus = wmem_map_new(wmem_file_scope(), g_int64_hash, g_int64_equal);
3564 }
3565 frame_ptr = (uint64_t*)wmem_memdup(wmem_file_scope(), &cur_frame_num, sizeof(uint64_t));
3566 wmem_map_insert(reassembly_info->multisegment_pdus, frame_ptr, cur_msp);
3567 } else {
3568 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", 3568, "cur_msp && cur_msp->start_offset_at_first_frame == offset"
))))
;
3569 reassembly_id = cur_msp->streaming_reassembly_id;
3570 }
3571 /* add first fragment of the new MSP to reassembly table */
3572 head = fragment_add(&streaming_reassembly_table, tvb, offset, pinfo, reassembly_id,
3573 NULL((void*)0), 0, length, true1);
3574
3575 if (head && frag_hf_items->hf_reassembled_in) {
3576 proto_item_set_generated(
3577 proto_tree_add_uint(segment_tree, *(frag_hf_items->hf_reassembled_in),
3578 tvb, offset, length, head->reassembled_in)
3579 );
3580 }
3581 proto_tree_add_bytes_format(segment_tree, hf_segment_data, tvb, offset, length,
3582 NULL((void*)0), "%s Segment data (%u byte%s)", label, length, plurality(length, "", "s")((length) == 1 ? ("") : ("s")));
3583 }
3584
3585 pinfo->can_desegment = save_can_desegment;
3586 pinfo->desegment_offset = save_desegment_offset;
3587 pinfo->desegment_len = save_desegment_len;
3588
3589 return orig_length;
3590}
3591
3592int
3593additional_bytes_expected_to_complete_reassembly(streaming_reassembly_info_t* reassembly_info)
3594{
3595 return reassembly_info->prev_deseg_len;
3596}
3597
3598/*
3599 * Editor modelines - https://www.wireshark.org/tools/modelines.html
3600 *
3601 * Local variables:
3602 * c-basic-offset: 8
3603 * tab-width: 8
3604 * indent-tabs-mode: t
3605 * End:
3606 *
3607 * vi: set shiftwidth=8 tabstop=8 noexpandtab:
3608 * :indentSize=8:tabSize=8:noTabs=false:
3609 */