xref: /qemu/net/dump.c (revision 7a4e543d) 
1 /*
2  * QEMU System Emulator
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include "qemu/osdep.h"
26 #include "clients.h"
27 #include "qemu-common.h"
28 #include "qemu/error-report.h"
29 #include "qemu/iov.h"
30 #include "qemu/log.h"
31 #include "qemu/timer.h"
32 #include "qapi/visitor.h"
33 #include "net/filter.h"
34 
35 typedef struct DumpState {
36     int64_t start_ts;
37     int fd;
38     int pcap_caplen;
39 } DumpState;
40 
41 #define PCAP_MAGIC 0xa1b2c3d4
42 
43 struct pcap_file_hdr {
44     uint32_t magic;
45     uint16_t version_major;
46     uint16_t version_minor;
47     int32_t thiszone;
48     uint32_t sigfigs;
49     uint32_t snaplen;
50     uint32_t linktype;
51 };
52 
53 struct pcap_sf_pkthdr {
54     struct {
55         int32_t tv_sec;
56         int32_t tv_usec;
57     } ts;
58     uint32_t caplen;
59     uint32_t len;
60 };
61 
62 static ssize_t dump_receive_iov(DumpState *s, const struct iovec *iov, int cnt)
63 {
64     struct pcap_sf_pkthdr hdr;
65     int64_t ts;
66     int caplen;
67     size_t size = iov_size(iov, cnt);
68     struct iovec dumpiov[cnt + 1];
69 
70     /* Early return in case of previous error. */
71     if (s->fd < 0) {
72         return size;
73     }
74 
75     ts = qemu_clock_get_us(QEMU_CLOCK_VIRTUAL);
76     caplen = size > s->pcap_caplen ? s->pcap_caplen : size;
77 
78     hdr.ts.tv_sec = ts / 1000000 + s->start_ts;
79     hdr.ts.tv_usec = ts % 1000000;
80     hdr.caplen = caplen;
81     hdr.len = size;
82 
83     dumpiov[0].iov_base = &hdr;
84     dumpiov[0].iov_len = sizeof(hdr);
85     cnt = iov_copy(&dumpiov[1], cnt, iov, cnt, 0, caplen);
86 
87     if (writev(s->fd, dumpiov, cnt + 1) != sizeof(hdr) + caplen) {
88         error_report("network dump write error - stopping dump");
89         close(s->fd);
90         s->fd = -1;
91     }
92 
93     return size;
94 }
95 
96 static void dump_cleanup(DumpState *s)
97 {
98     close(s->fd);
99     s->fd = -1;
100 }
101 
102 static int net_dump_state_init(DumpState *s, const char *filename,
103                                int len, Error **errp)
104 {
105     struct pcap_file_hdr hdr;
106     struct tm tm;
107     int fd;
108 
109     fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY | O_BINARY, 0644);
110     if (fd < 0) {
111         error_setg_errno(errp, errno, "-net dump: can't open %s", filename);
112         return -1;
113     }
114 
115     hdr.magic = PCAP_MAGIC;
116     hdr.version_major = 2;
117     hdr.version_minor = 4;
118     hdr.thiszone = 0;
119     hdr.sigfigs = 0;
120     hdr.snaplen = len;
121     hdr.linktype = 1;
122 
123     if (write(fd, &hdr, sizeof(hdr)) < sizeof(hdr)) {
124         error_setg_errno(errp, errno, "-net dump write error");
125         close(fd);
126         return -1;
127     }
128 
129     s->fd = fd;
130     s->pcap_caplen = len;
131 
132     qemu_get_timedate(&tm, 0);
133     s->start_ts = mktime(&tm);
134 
135     return 0;
136 }
137 
138 /* Dumping via VLAN netclient */
139 
140 struct DumpNetClient {
141     NetClientState nc;
142     DumpState ds;
143 };
144 typedef struct DumpNetClient DumpNetClient;
145 
146 static ssize_t dumpclient_receive(NetClientState *nc, const uint8_t *buf,
147                                   size_t size)
148 {
149     DumpNetClient *dc = DO_UPCAST(DumpNetClient, nc, nc);
150     struct iovec iov = {
151         .iov_base = (void *)buf,
152         .iov_len = size
153     };
154 
155     return dump_receive_iov(&dc->ds, &iov, 1);
156 }
157 
158 static ssize_t dumpclient_receive_iov(NetClientState *nc,
159                                       const struct iovec *iov, int cnt)
160 {
161     DumpNetClient *dc = DO_UPCAST(DumpNetClient, nc, nc);
162 
163     return dump_receive_iov(&dc->ds, iov, cnt);
164 }
165 
166 static void dumpclient_cleanup(NetClientState *nc)
167 {
168     DumpNetClient *dc = DO_UPCAST(DumpNetClient, nc, nc);
169 
170     dump_cleanup(&dc->ds);
171 }
172 
173 static NetClientInfo net_dump_info = {
174     .type = NET_CLIENT_OPTIONS_KIND_DUMP,
175     .size = sizeof(DumpNetClient),
176     .receive = dumpclient_receive,
177     .receive_iov = dumpclient_receive_iov,
178     .cleanup = dumpclient_cleanup,
179 };
180 
181 int net_init_dump(const NetClientOptions *opts, const char *name,
182                   NetClientState *peer, Error **errp)
183 {
184     int len, rc;
185     const char *file;
186     char def_file[128];
187     const NetdevDumpOptions *dump;
188     NetClientState *nc;
189     DumpNetClient *dnc;
190 
191     assert(opts->type == NET_CLIENT_OPTIONS_KIND_DUMP);
192     dump = opts->u.dump;
193 
194     assert(peer);
195 
196     if (dump->has_file) {
197         file = dump->file;
198     } else {
199         int id;
200         int ret;
201 
202         ret = net_hub_id_for_client(peer, &id);
203         assert(ret == 0); /* peer must be on a hub */
204 
205         snprintf(def_file, sizeof(def_file), "qemu-vlan%d.pcap", id);
206         file = def_file;
207     }
208 
209     if (dump->has_len) {
210         if (dump->len > INT_MAX) {
211             error_setg(errp, "invalid length: %"PRIu64, dump->len);
212             return -1;
213         }
214         len = dump->len;
215     } else {
216         len = 65536;
217     }
218 
219     nc = qemu_new_net_client(&net_dump_info, peer, "dump", name);
220     snprintf(nc->info_str, sizeof(nc->info_str),
221              "dump to %s (len=%d)", file, len);
222 
223     dnc = DO_UPCAST(DumpNetClient, nc, nc);
224     rc = net_dump_state_init(&dnc->ds, file, len, errp);
225     if (rc) {
226         qemu_del_net_client(nc);
227     }
228     return rc;
229 }
230 
231 /* Dumping via filter */
232 
233 #define TYPE_FILTER_DUMP "filter-dump"
234 
235 #define FILTER_DUMP(obj) \
236     OBJECT_CHECK(NetFilterDumpState, (obj), TYPE_FILTER_DUMP)
237 
238 struct NetFilterDumpState {
239     NetFilterState nfs;
240     DumpState ds;
241     char *filename;
242     uint32_t maxlen;
243 };
244 typedef struct NetFilterDumpState NetFilterDumpState;
245 
246 static ssize_t filter_dump_receive_iov(NetFilterState *nf, NetClientState *sndr,
247                                        unsigned flags, const struct iovec *iov,
248                                        int iovcnt, NetPacketSent *sent_cb)
249 {
250     NetFilterDumpState *nfds = FILTER_DUMP(nf);
251 
252     dump_receive_iov(&nfds->ds, iov, iovcnt);
253     return 0;
254 }
255 
256 static void filter_dump_cleanup(NetFilterState *nf)
257 {
258     NetFilterDumpState *nfds = FILTER_DUMP(nf);
259 
260     dump_cleanup(&nfds->ds);
261 }
262 
263 static void filter_dump_setup(NetFilterState *nf, Error **errp)
264 {
265     NetFilterDumpState *nfds = FILTER_DUMP(nf);
266 
267     if (!nfds->filename) {
268         error_setg(errp, "dump filter needs 'file' property set!");
269         return;
270     }
271 
272     net_dump_state_init(&nfds->ds, nfds->filename, nfds->maxlen, errp);
273 }
274 
275 static void filter_dump_get_maxlen(Object *obj, Visitor *v, const char *name,
276                                    void *opaque, Error **errp)
277 {
278     NetFilterDumpState *nfds = FILTER_DUMP(obj);
279     uint32_t value = nfds->maxlen;
280 
281     visit_type_uint32(v, name, &value, errp);
282 }
283 
284 static void filter_dump_set_maxlen(Object *obj, Visitor *v, const char *name,
285                                    void *opaque, Error **errp)
286 {
287     NetFilterDumpState *nfds = FILTER_DUMP(obj);
288     Error *local_err = NULL;
289     uint32_t value;
290 
291     visit_type_uint32(v, name, &value, &local_err);
292     if (local_err) {
293         goto out;
294     }
295     if (value == 0) {
296         error_setg(&local_err, "Property '%s.%s' doesn't take value '%u'",
297                    object_get_typename(obj), name, value);
298         goto out;
299     }
300     nfds->maxlen = value;
301 
302 out:
303     error_propagate(errp, local_err);
304 }
305 
306 static char *file_dump_get_filename(Object *obj, Error **errp)
307 {
308     NetFilterDumpState *nfds = FILTER_DUMP(obj);
309 
310     return g_strdup(nfds->filename);
311 }
312 
313 static void file_dump_set_filename(Object *obj, const char *value, Error **errp)
314 {
315    NetFilterDumpState *nfds = FILTER_DUMP(obj);
316 
317     g_free(nfds->filename);
318     nfds->filename = g_strdup(value);
319 }
320 
321 static void filter_dump_instance_init(Object *obj)
322 {
323     NetFilterDumpState *nfds = FILTER_DUMP(obj);
324 
325     nfds->maxlen = 65536;
326 
327     object_property_add(obj, "maxlen", "int", filter_dump_get_maxlen,
328                         filter_dump_set_maxlen, NULL, NULL, NULL);
329     object_property_add_str(obj, "file", file_dump_get_filename,
330                             file_dump_set_filename, NULL);
331 }
332 
333 static void filter_dump_instance_finalize(Object *obj)
334 {
335     NetFilterDumpState *nfds = FILTER_DUMP(obj);
336 
337     g_free(nfds->filename);
338 }
339 
340 static void filter_dump_class_init(ObjectClass *oc, void *data)
341 {
342     NetFilterClass *nfc = NETFILTER_CLASS(oc);
343 
344     nfc->setup = filter_dump_setup;
345     nfc->cleanup = filter_dump_cleanup;
346     nfc->receive_iov = filter_dump_receive_iov;
347 }
348 
349 static const TypeInfo filter_dump_info = {
350     .name = TYPE_FILTER_DUMP,
351     .parent = TYPE_NETFILTER,
352     .class_init = filter_dump_class_init,
353     .instance_init = filter_dump_instance_init,
354     .instance_finalize = filter_dump_instance_finalize,
355     .instance_size = sizeof(NetFilterDumpState),
356 };
357 
358 static void filter_dump_register_types(void)
359 {
360     type_register_static(&filter_dump_info);
361 }
362 
363 type_init(filter_dump_register_types);
364