xref: /qemu/net/dump.c (revision 9c4218e9) 
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 "clients.h"
26 #include "qemu-common.h"
27 #include "qemu/error-report.h"
28 #include "qemu/iov.h"
29 #include "qemu/log.h"
30 #include "qemu/timer.h"
31 #include "qapi/visitor.h"
32 #include "net/filter.h"
33 
34 typedef struct DumpState {
35     int64_t start_ts;
36     int fd;
37     int pcap_caplen;
38 } DumpState;
39 
40 #define PCAP_MAGIC 0xa1b2c3d4
41 
42 struct pcap_file_hdr {
43     uint32_t magic;
44     uint16_t version_major;
45     uint16_t version_minor;
46     int32_t thiszone;
47     uint32_t sigfigs;
48     uint32_t snaplen;
49     uint32_t linktype;
50 };
51 
52 struct pcap_sf_pkthdr {
53     struct {
54         int32_t tv_sec;
55         int32_t tv_usec;
56     } ts;
57     uint32_t caplen;
58     uint32_t len;
59 };
60 
61 static ssize_t dump_receive_iov(DumpState *s, const struct iovec *iov, int cnt)
62 {
63     struct pcap_sf_pkthdr hdr;
64     int64_t ts;
65     int caplen;
66     size_t size = iov_size(iov, cnt);
67     struct iovec dumpiov[cnt + 1];
68 
69     /* Early return in case of previous error. */
70     if (s->fd < 0) {
71         return size;
72     }
73 
74     ts = qemu_clock_get_us(QEMU_CLOCK_VIRTUAL);
75     caplen = size > s->pcap_caplen ? s->pcap_caplen : size;
76 
77     hdr.ts.tv_sec = ts / 1000000 + s->start_ts;
78     hdr.ts.tv_usec = ts % 1000000;
79     hdr.caplen = caplen;
80     hdr.len = size;
81 
82     dumpiov[0].iov_base = &hdr;
83     dumpiov[0].iov_len = sizeof(hdr);
84     cnt = iov_copy(&dumpiov[1], cnt, iov, cnt, 0, caplen);
85 
86     if (writev(s->fd, dumpiov, cnt + 1) != sizeof(hdr) + caplen) {
87         error_report("network dump write error - stopping dump");
88         close(s->fd);
89         s->fd = -1;
90     }
91 
92     return size;
93 }
94 
95 static void dump_cleanup(DumpState *s)
96 {
97     close(s->fd);
98     s->fd = -1;
99 }
100 
101 static int net_dump_state_init(DumpState *s, const char *filename,
102                                int len, Error **errp)
103 {
104     struct pcap_file_hdr hdr;
105     struct tm tm;
106     int fd;
107 
108     fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY | O_BINARY, 0644);
109     if (fd < 0) {
110         error_setg_errno(errp, errno, "-net dump: can't open %s", filename);
111         return -1;
112     }
113 
114     hdr.magic = PCAP_MAGIC;
115     hdr.version_major = 2;
116     hdr.version_minor = 4;
117     hdr.thiszone = 0;
118     hdr.sigfigs = 0;
119     hdr.snaplen = len;
120     hdr.linktype = 1;
121 
122     if (write(fd, &hdr, sizeof(hdr)) < sizeof(hdr)) {
123         error_setg_errno(errp, errno, "-net dump write error");
124         close(fd);
125         return -1;
126     }
127 
128     s->fd = fd;
129     s->pcap_caplen = len;
130 
131     qemu_get_timedate(&tm, 0);
132     s->start_ts = mktime(&tm);
133 
134     return 0;
135 }
136 
137 /* Dumping via VLAN netclient */
138 
139 struct DumpNetClient {
140     NetClientState nc;
141     DumpState ds;
142 };
143 typedef struct DumpNetClient DumpNetClient;
144 
145 static ssize_t dumpclient_receive(NetClientState *nc, const uint8_t *buf,
146                                   size_t size)
147 {
148     DumpNetClient *dc = DO_UPCAST(DumpNetClient, nc, nc);
149     struct iovec iov = {
150         .iov_base = (void *)buf,
151         .iov_len = size
152     };
153 
154     return dump_receive_iov(&dc->ds, &iov, 1);
155 }
156 
157 static ssize_t dumpclient_receive_iov(NetClientState *nc,
158                                       const struct iovec *iov, int cnt)
159 {
160     DumpNetClient *dc = DO_UPCAST(DumpNetClient, nc, nc);
161 
162     return dump_receive_iov(&dc->ds, iov, cnt);
163 }
164 
165 static void dumpclient_cleanup(NetClientState *nc)
166 {
167     DumpNetClient *dc = DO_UPCAST(DumpNetClient, nc, nc);
168 
169     dump_cleanup(&dc->ds);
170 }
171 
172 static NetClientInfo net_dump_info = {
173     .type = NET_CLIENT_OPTIONS_KIND_DUMP,
174     .size = sizeof(DumpNetClient),
175     .receive = dumpclient_receive,
176     .receive_iov = dumpclient_receive_iov,
177     .cleanup = dumpclient_cleanup,
178 };
179 
180 int net_init_dump(const NetClientOptions *opts, const char *name,
181                   NetClientState *peer, Error **errp)
182 {
183     int len, rc;
184     const char *file;
185     char def_file[128];
186     const NetdevDumpOptions *dump;
187     NetClientState *nc;
188     DumpNetClient *dnc;
189 
190     assert(opts->type == NET_CLIENT_OPTIONS_KIND_DUMP);
191     dump = opts->u.dump;
192 
193     assert(peer);
194 
195     if (dump->has_file) {
196         file = dump->file;
197     } else {
198         int id;
199         int ret;
200 
201         ret = net_hub_id_for_client(peer, &id);
202         assert(ret == 0); /* peer must be on a hub */
203 
204         snprintf(def_file, sizeof(def_file), "qemu-vlan%d.pcap", id);
205         file = def_file;
206     }
207 
208     if (dump->has_len) {
209         if (dump->len > INT_MAX) {
210             error_setg(errp, "invalid length: %"PRIu64, dump->len);
211             return -1;
212         }
213         len = dump->len;
214     } else {
215         len = 65536;
216     }
217 
218     nc = qemu_new_net_client(&net_dump_info, peer, "dump", name);
219     snprintf(nc->info_str, sizeof(nc->info_str),
220              "dump to %s (len=%d)", file, len);
221 
222     dnc = DO_UPCAST(DumpNetClient, nc, nc);
223     rc = net_dump_state_init(&dnc->ds, file, len, errp);
224     if (rc) {
225         qemu_del_net_client(nc);
226     }
227     return rc;
228 }
229 
230 /* Dumping via filter */
231 
232 #define TYPE_FILTER_DUMP "filter-dump"
233 
234 #define FILTER_DUMP(obj) \
235     OBJECT_CHECK(NetFilterDumpState, (obj), TYPE_FILTER_DUMP)
236 
237 struct NetFilterDumpState {
238     NetFilterState nfs;
239     DumpState ds;
240     char *filename;
241     uint32_t maxlen;
242 };
243 typedef struct NetFilterDumpState NetFilterDumpState;
244 
245 static ssize_t filter_dump_receive_iov(NetFilterState *nf, NetClientState *sndr,
246                                        unsigned flags, const struct iovec *iov,
247                                        int iovcnt, NetPacketSent *sent_cb)
248 {
249     NetFilterDumpState *nfds = FILTER_DUMP(nf);
250 
251     dump_receive_iov(&nfds->ds, iov, iovcnt);
252     return 0;
253 }
254 
255 static void filter_dump_cleanup(NetFilterState *nf)
256 {
257     NetFilterDumpState *nfds = FILTER_DUMP(nf);
258 
259     dump_cleanup(&nfds->ds);
260 }
261 
262 static void filter_dump_setup(NetFilterState *nf, Error **errp)
263 {
264     NetFilterDumpState *nfds = FILTER_DUMP(nf);
265 
266     if (!nfds->filename) {
267         error_setg(errp, "dump filter needs 'file' property set!");
268         return;
269     }
270 
271     net_dump_state_init(&nfds->ds, nfds->filename, nfds->maxlen, errp);
272 }
273 
274 static void filter_dump_get_maxlen(Object *obj, Visitor *v, void *opaque,
275                                    const char *name, Error **errp)
276 {
277     NetFilterDumpState *nfds = FILTER_DUMP(obj);
278     uint32_t value = nfds->maxlen;
279 
280     visit_type_uint32(v, &value, name, errp);
281 }
282 
283 static void filter_dump_set_maxlen(Object *obj, Visitor *v, void *opaque,
284                                    const char *name, Error **errp)
285 {
286     NetFilterDumpState *nfds = FILTER_DUMP(obj);
287     Error *local_err = NULL;
288     uint32_t value;
289 
290     visit_type_uint32(v, &value, name, &local_err);
291     if (local_err) {
292         goto out;
293     }
294     if (value == 0) {
295         error_setg(&local_err, "Property '%s.%s' doesn't take value '%u'",
296                    object_get_typename(obj), name, value);
297         goto out;
298     }
299     nfds->maxlen = value;
300 
301 out:
302     error_propagate(errp, local_err);
303 }
304 
305 static char *file_dump_get_filename(Object *obj, Error **errp)
306 {
307     NetFilterDumpState *nfds = FILTER_DUMP(obj);
308 
309     return g_strdup(nfds->filename);
310 }
311 
312 static void file_dump_set_filename(Object *obj, const char *value, Error **errp)
313 {
314    NetFilterDumpState *nfds = FILTER_DUMP(obj);
315 
316     g_free(nfds->filename);
317     nfds->filename = g_strdup(value);
318 }
319 
320 static void filter_dump_instance_init(Object *obj)
321 {
322     NetFilterDumpState *nfds = FILTER_DUMP(obj);
323 
324     nfds->maxlen = 65536;
325 
326     object_property_add(obj, "maxlen", "int", filter_dump_get_maxlen,
327                         filter_dump_set_maxlen, NULL, NULL, NULL);
328     object_property_add_str(obj, "file", file_dump_get_filename,
329                             file_dump_set_filename, NULL);
330 }
331 
332 static void filter_dump_instance_finalize(Object *obj)
333 {
334     NetFilterDumpState *nfds = FILTER_DUMP(obj);
335 
336     g_free(nfds->filename);
337 }
338 
339 static void filter_dump_class_init(ObjectClass *oc, void *data)
340 {
341     NetFilterClass *nfc = NETFILTER_CLASS(oc);
342 
343     nfc->setup = filter_dump_setup;
344     nfc->cleanup = filter_dump_cleanup;
345     nfc->receive_iov = filter_dump_receive_iov;
346 }
347 
348 static const TypeInfo filter_dump_info = {
349     .name = TYPE_FILTER_DUMP,
350     .parent = TYPE_NETFILTER,
351     .class_init = filter_dump_class_init,
352     .instance_init = filter_dump_instance_init,
353     .instance_finalize = filter_dump_instance_finalize,
354     .instance_size = sizeof(NetFilterDumpState),
355 };
356 
357 static void filter_dump_register_types(void)
358 {
359     type_register_static(&filter_dump_info);
360 }
361 
362 type_init(filter_dump_register_types);
363