2 * Implements a tvbuff for frame
4 * Wireshark - Network traffic analyzer
5 * By Gerald Combs <gerald@wireshark.org>
6 * Copyright 1998 Gerald Combs
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version 2
11 * of the License, or (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
27 #include <epan/packet.h>
28 #include <epan/tvbuff-int.h>
29 #include <epan/tvbuff.h>
31 #include "frame_tvbuff.h"
34 #include "wtap-int.h" /* for ->random_fh */
39 Buffer *buf; /* Packet data */
41 wtap *wth; /**< Wiretap session */
42 gint64 file_off; /**< File offset */
48 frame_read(struct tvb_frame *frame_tvb, struct wtap_pkthdr *phdr, Buffer *buf)
53 /* sanity check, capture file was closed? */
54 if (cfile.wth != frame_tvb->wth)
57 /* XXX, what if phdr->caplen isn't equal to
58 * frame_tvb->tvb.length + frame_tvb->offset?
60 if (!wtap_seek_read(frame_tvb->wth, frame_tvb->file_off, phdr, buf, &err, &err_info)) {
61 /* XXX - report error! */
63 case WTAP_ERR_BAD_FILE:
73 frame_cache(struct tvb_frame *frame_tvb)
75 struct wtap_pkthdr phdr; /* Packet header */
77 wtap_phdr_init(&phdr);
79 if (frame_tvb->buf == NULL) {
80 frame_tvb->buf = (struct Buffer *) g_malloc(sizeof(struct Buffer));
82 /* XXX, register frame_tvb to some list which frees from time to time not used buffers :] */
83 ws_buffer_init(frame_tvb->buf, frame_tvb->tvb.length + frame_tvb->offset);
85 if (!frame_read(frame_tvb, &phdr, frame_tvb->buf))
86 { /* TODO: THROW(???); */ }
89 frame_tvb->tvb.real_data = ws_buffer_start_ptr(frame_tvb->buf) + frame_tvb->offset;
91 wtap_phdr_cleanup(&phdr);
95 frame_free(tvbuff_t *tvb)
97 struct tvb_frame *frame_tvb = (struct tvb_frame *) tvb;
100 ws_buffer_free(frame_tvb->buf);
102 g_free(frame_tvb->buf);
106 static const guint8 *
107 frame_get_ptr(tvbuff_t *tvb, guint abs_offset, guint abs_length _U_)
109 struct tvb_frame *frame_tvb = (struct tvb_frame *) tvb;
111 frame_cache(frame_tvb);
113 return tvb->real_data + abs_offset;
117 frame_memcpy(tvbuff_t *tvb, void *target, guint abs_offset, guint abs_length)
119 struct tvb_frame *frame_tvb = (struct tvb_frame *) tvb;
121 frame_cache(frame_tvb);
123 return memcpy(target, tvb->real_data + abs_offset, abs_length);
127 frame_find_guint8(tvbuff_t *tvb, guint abs_offset, guint limit, guint8 needle)
129 struct tvb_frame *frame_tvb = (struct tvb_frame *) tvb;
130 const guint8 *result;
132 frame_cache(frame_tvb);
134 result = (const guint8 *)memchr(tvb->real_data + abs_offset, needle, limit);
136 return (gint) (result - tvb->real_data);
142 frame_pbrk_guint8(tvbuff_t *tvb, guint abs_offset, guint limit, const ws_mempbrk_pattern* pattern, guchar *found_needle)
144 struct tvb_frame *frame_tvb = (struct tvb_frame *) tvb;
146 frame_cache(frame_tvb);
148 return tvb_ws_mempbrk_pattern_guint8(tvb, abs_offset, limit, pattern, found_needle);
152 frame_offset(const tvbuff_t *tvb _U_, const guint counter)
154 /* XXX: frame_tvb->offset */
158 static tvbuff_t *frame_clone(tvbuff_t *tvb, guint abs_offset, guint abs_length);
160 static const struct tvb_ops tvb_frame_ops = {
161 sizeof(struct tvb_frame), /* size */
163 frame_free, /* free */
164 frame_offset, /* offset */
165 frame_get_ptr, /* get_ptr */
166 frame_memcpy, /* memcpy */
167 frame_find_guint8, /* find_guint8 */
168 frame_pbrk_guint8, /* pbrk_guint8 */
169 frame_clone, /* clone */
172 /* based on tvb_new_real_data() */
174 frame_tvbuff_new(const frame_data *fd, const guint8 *buf)
176 struct tvb_frame *frame_tvb;
179 tvb = tvb_new(&tvb_frame_ops);
182 * XXX - currently, the length arguments in
183 * tvbuff structure are signed, but the captured
184 * and reported length values are unsigned; this means
185 * that length values > 2^31 - 1 will appear as
188 * Captured length values that large will already
189 * have been filtered out by the Wiretap modules
190 * (the file will be reported as corrupted), to
191 * avoid trying to allocate large chunks of data.
193 * Reported length values will not have been
194 * filtered out, and should not be filtered out,
195 * as those lengths are not necessarily invalid.
197 * For now, we clip the reported length at G_MAXINT
199 * (XXX, is this still a problem?) There was an exception when we call
200 * tvb_new_real_data() now there's no one
203 tvb->real_data = buf;
204 tvb->length = fd->cap_len;
205 tvb->reported_length = fd->pkt_len > G_MAXINT ? G_MAXINT : fd->pkt_len;
206 tvb->initialized = TRUE;
209 * This is the top-level real tvbuff for this data source,
210 * so its data source tvbuff is itself.
214 frame_tvb = (struct tvb_frame *) tvb;
216 /* XXX, wtap_can_seek() */
217 if (cfile.wth && cfile.wth->random_fh
218 #ifdef WANT_PACKET_EDITOR
219 && fd->file_off != -1 /* generic clone for modified packets */
222 frame_tvb->wth = cfile.wth;
223 frame_tvb->file_off = fd->file_off;
224 frame_tvb->offset = 0;
226 frame_tvb->wth = NULL;
228 frame_tvb->buf = NULL;
234 frame_tvbuff_new_buffer(const frame_data *fd, Buffer *buf)
236 return frame_tvbuff_new(fd, ws_buffer_start_ptr(buf));
240 frame_clone(tvbuff_t *tvb, guint abs_offset, guint abs_length)
242 struct tvb_frame *frame_tvb = (struct tvb_frame *) tvb;
244 tvbuff_t *cloned_tvb;
245 struct tvb_frame *cloned_frame_tvb;
247 /* file not seekable */
251 abs_offset += frame_tvb->offset;
253 cloned_tvb = tvb_new(&tvb_frame_ops);
255 /* data will be read when needed */
256 cloned_tvb->real_data = NULL;
257 cloned_tvb->length = abs_length;
258 cloned_tvb->reported_length = abs_length; /* XXX? */
259 cloned_tvb->initialized = TRUE;
262 * This is the top-level real tvbuff for this data source,
263 * so its data source tvbuff is itself.
265 cloned_tvb->ds_tvb = cloned_tvb;
267 cloned_frame_tvb = (struct tvb_frame *) cloned_tvb;
268 cloned_frame_tvb->wth = frame_tvb->wth;
269 cloned_frame_tvb->file_off = frame_tvb->file_off;
270 cloned_frame_tvb->offset = abs_offset;
271 cloned_frame_tvb->buf = NULL;
277 /* based on tvb_new_real_data() */
279 file_tvbuff_new(const frame_data *fd, const guint8 *buf)
281 struct tvb_frame *frame_tvb;
284 tvb = tvb_new(&tvb_frame_ops);
287 * XXX - currently, the length arguments in
288 * tvbuff structure are signed, but the captured
289 * and reported length values are unsigned; this means
290 * that length values > 2^31 - 1 will appear as
293 * Captured length values that large will already
294 * have been filtered out by the Wiretap modules
295 * (the file will be reported as corrupted), to
296 * avoid trying to allocate large chunks of data.
298 * Reported length values will not have been
299 * filtered out, and should not be filtered out,
300 * as those lengths are not necessarily invalid.
302 * For now, we clip the reported length at G_MAXINT
304 * (XXX, is this still a problem?) There was an exception when we call
305 * tvb_new_real_data() now there's no one
308 tvb->real_data = buf;
309 tvb->length = fd->cap_len;
310 tvb->reported_length = fd->pkt_len > G_MAXINT ? G_MAXINT : fd->pkt_len;
311 tvb->initialized = TRUE;
314 * This is the top-level real tvbuff for this data source,
315 * so its data source tvbuff is itself.
319 frame_tvb = (struct tvb_frame *) tvb;
321 /* XXX, wtap_can_seek() */
322 if (cfile.wth && cfile.wth->random_fh
323 #ifdef WANT_PACKET_EDITOR
324 && fd->file_off != -1 /* generic clone for modified packets */
327 frame_tvb->wth = cfile.wth;
328 frame_tvb->file_off = fd->file_off;
329 frame_tvb->offset = 0;
331 frame_tvb->wth = NULL;
333 frame_tvb->buf = NULL;
339 file_tvbuff_new_buffer(const frame_data *fd, Buffer *buf)
341 return frame_tvbuff_new(fd, ws_buffer_start_ptr(buf));
345 * Editor modelines - http://www.wireshark.org/tools/modelines.html
350 * indent-tabs-mode: t
353 * vi: set shiftwidth=8 tabstop=8 noexpandtab:
354 * :indentSize=8:tabSize=8:noTabs=false: