### Bug Summary

File: | builds/wireshark/wireshark/epan/reassemble.c
Warning: | line 1905, column 12 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-21/lib/clang/21 -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/lua5.4 -isystem /usr/include/libxml2 -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-21/lib/clang/21/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fmacro-prefix-map=/builds/wireshark/wireshark/= -fmacro-prefix-map=/builds/wireshark/wireshark/build/= -fmacro-prefix-map=../= -Wno-format-nonliteral -std=gnu11 -ferror-limit 19 -fvisibility=hidden -fwrapv -fwrapv-pointer -fstrict-flex-arrays=3 -stack-protector 2 -fstack-clash-protection -fcf-protection=full -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fexceptions -fcolor-diagnostics -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /builds/wireshark/wireshark/sbout/2026-04-26-100332-3641-1 -x c /builds/wireshark/wireshark/epan/reassemble.c

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