xref: /openbmc/qemu/net/dump.c (revision 1f7685fa)
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 "qapi/error.h"
28 #include "qemu-common.h"
29 #include "qemu/error-report.h"
30 #include "qemu/iov.h"
31 #include "qemu/log.h"
32 #include "qemu/timer.h"
33 #include "qapi/visitor.h"
34 #include "net/filter.h"
35 
36 typedef struct DumpState {
37     int64_t start_ts;
38     int fd;
39     int pcap_caplen;
40 } DumpState;
41 
42 #define PCAP_MAGIC 0xa1b2c3d4
43 
44 struct pcap_file_hdr {
45     uint32_t magic;
46     uint16_t version_major;
47     uint16_t version_minor;
48     int32_t thiszone;
49     uint32_t sigfigs;
50     uint32_t snaplen;
51     uint32_t linktype;
52 };
53 
54 struct pcap_sf_pkthdr {
55     struct {
56         int32_t tv_sec;
57         int32_t tv_usec;
58     } ts;
59     uint32_t caplen;
60     uint32_t len;
61 };
62 
63 static ssize_t dump_receive_iov(DumpState *s, const struct iovec *iov, int cnt)
64 {
65     struct pcap_sf_pkthdr hdr;
66     int64_t ts;
67     int caplen;
68     size_t size = iov_size(iov, cnt);
69     struct iovec dumpiov[cnt + 1];
70 
71     /* Early return in case of previous error. */
72     if (s->fd < 0) {
73         return size;
74     }
75 
76     ts = qemu_clock_get_us(QEMU_CLOCK_VIRTUAL);
77     caplen = size > s->pcap_caplen ? s->pcap_caplen : size;
78 
79     hdr.ts.tv_sec = ts / 1000000 + s->start_ts;
80     hdr.ts.tv_usec = ts % 1000000;
81     hdr.caplen = caplen;
82     hdr.len = size;
83 
84     dumpiov[0].iov_base = &hdr;
85     dumpiov[0].iov_len = sizeof(hdr);
86     cnt = iov_copy(&dumpiov[1], cnt, iov, cnt, 0, caplen);
87 
88     if (writev(s->fd, dumpiov, cnt + 1) != sizeof(hdr) + caplen) {
89         error_report("network dump write error - stopping dump");
90         close(s->fd);
91         s->fd = -1;
92     }
93 
94     return size;
95 }
96 
97 static void dump_cleanup(DumpState *s)
98 {
99     close(s->fd);
100     s->fd = -1;
101 }
102 
103 static int net_dump_state_init(DumpState *s, const char *filename,
104                                int len, Error **errp)
105 {
106     struct pcap_file_hdr hdr;
107     struct tm tm;
108     int fd;
109 
110     fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY | O_BINARY, 0644);
111     if (fd < 0) {
112         error_setg_errno(errp, errno, "-net dump: can't open %s", filename);
113         return -1;
114     }
115 
116     hdr.magic = PCAP_MAGIC;
117     hdr.version_major = 2;
118     hdr.version_minor = 4;
119     hdr.thiszone = 0;
120     hdr.sigfigs = 0;
121     hdr.snaplen = len;
122     hdr.linktype = 1;
123 
124     if (write(fd, &hdr, sizeof(hdr)) < sizeof(hdr)) {
125         error_setg_errno(errp, errno, "-net dump write error");
126         close(fd);
127         return -1;
128     }
129 
130     s->fd = fd;
131     s->pcap_caplen = len;
132 
133     qemu_get_timedate(&tm, 0);
134     s->start_ts = mktime(&tm);
135 
136     return 0;
137 }
138 
139 /* Dumping via VLAN netclient */
140 
141 struct DumpNetClient {
142     NetClientState nc;
143     DumpState ds;
144 };
145 typedef struct DumpNetClient DumpNetClient;
146 
147 static ssize_t dumpclient_receive(NetClientState *nc, const uint8_t *buf,
148                                   size_t size)
149 {
150     DumpNetClient *dc = DO_UPCAST(DumpNetClient, nc, nc);
151     struct iovec iov = {
152         .iov_base = (void *)buf,
153         .iov_len = size
154     };
155 
156     return dump_receive_iov(&dc->ds, &iov, 1);
157 }
158 
159 static ssize_t dumpclient_receive_iov(NetClientState *nc,
160                                       const struct iovec *iov, int cnt)
161 {
162     DumpNetClient *dc = DO_UPCAST(DumpNetClient, nc, nc);
163 
164     return dump_receive_iov(&dc->ds, iov, cnt);
165 }
166 
167 static void dumpclient_cleanup(NetClientState *nc)
168 {
169     DumpNetClient *dc = DO_UPCAST(DumpNetClient, nc, nc);
170 
171     dump_cleanup(&dc->ds);
172 }
173 
174 static NetClientInfo net_dump_info = {
175     .type = NET_CLIENT_OPTIONS_KIND_DUMP,
176     .size = sizeof(DumpNetClient),
177     .receive = dumpclient_receive,
178     .receive_iov = dumpclient_receive_iov,
179     .cleanup = dumpclient_cleanup,
180 };
181 
182 int net_init_dump(const NetClientOptions *opts, const char *name,
183                   NetClientState *peer, Error **errp)
184 {
185     int len, rc;
186     const char *file;
187     char def_file[128];
188     const NetdevDumpOptions *dump;
189     NetClientState *nc;
190     DumpNetClient *dnc;
191 
192     assert(opts->type == NET_CLIENT_OPTIONS_KIND_DUMP);
193     dump = opts->u.dump.data;
194 
195     assert(peer);
196 
197     if (dump->has_file) {
198         file = dump->file;
199     } else {
200         int id;
201         int ret;
202 
203         ret = net_hub_id_for_client(peer, &id);
204         assert(ret == 0); /* peer must be on a hub */
205 
206         snprintf(def_file, sizeof(def_file), "qemu-vlan%d.pcap", id);
207         file = def_file;
208     }
209 
210     if (dump->has_len) {
211         if (dump->len > INT_MAX) {
212             error_setg(errp, "invalid length: %"PRIu64, dump->len);
213             return -1;
214         }
215         len = dump->len;
216     } else {
217         len = 65536;
218     }
219 
220     nc = qemu_new_net_client(&net_dump_info, peer, "dump", name);
221     snprintf(nc->info_str, sizeof(nc->info_str),
222              "dump to %s (len=%d)", file, len);
223 
224     dnc = DO_UPCAST(DumpNetClient, nc, nc);
225     rc = net_dump_state_init(&dnc->ds, file, len, errp);
226     if (rc) {
227         qemu_del_net_client(nc);
228     }
229     return rc;
230 }
231 
232 /* Dumping via filter */
233 
234 #define TYPE_FILTER_DUMP "filter-dump"
235 
236 #define FILTER_DUMP(obj) \
237     OBJECT_CHECK(NetFilterDumpState, (obj), TYPE_FILTER_DUMP)
238 
239 struct NetFilterDumpState {
240     NetFilterState nfs;
241     DumpState ds;
242     char *filename;
243     uint32_t maxlen;
244 };
245 typedef struct NetFilterDumpState NetFilterDumpState;
246 
247 static ssize_t filter_dump_receive_iov(NetFilterState *nf, NetClientState *sndr,
248                                        unsigned flags, const struct iovec *iov,
249                                        int iovcnt, NetPacketSent *sent_cb)
250 {
251     NetFilterDumpState *nfds = FILTER_DUMP(nf);
252 
253     dump_receive_iov(&nfds->ds, iov, iovcnt);
254     return 0;
255 }
256 
257 static void filter_dump_cleanup(NetFilterState *nf)
258 {
259     NetFilterDumpState *nfds = FILTER_DUMP(nf);
260 
261     dump_cleanup(&nfds->ds);
262 }
263 
264 static void filter_dump_setup(NetFilterState *nf, Error **errp)
265 {
266     NetFilterDumpState *nfds = FILTER_DUMP(nf);
267 
268     if (!nfds->filename) {
269         error_setg(errp, "dump filter needs 'file' property set!");
270         return;
271     }
272 
273     net_dump_state_init(&nfds->ds, nfds->filename, nfds->maxlen, errp);
274 }
275 
276 static void filter_dump_get_maxlen(Object *obj, Visitor *v, const char *name,
277                                    void *opaque, Error **errp)
278 {
279     NetFilterDumpState *nfds = FILTER_DUMP(obj);
280     uint32_t value = nfds->maxlen;
281 
282     visit_type_uint32(v, name, &value, errp);
283 }
284 
285 static void filter_dump_set_maxlen(Object *obj, Visitor *v, const char *name,
286                                    void *opaque, Error **errp)
287 {
288     NetFilterDumpState *nfds = FILTER_DUMP(obj);
289     Error *local_err = NULL;
290     uint32_t value;
291 
292     visit_type_uint32(v, name, &value, &local_err);
293     if (local_err) {
294         goto out;
295     }
296     if (value == 0) {
297         error_setg(&local_err, "Property '%s.%s' doesn't take value '%u'",
298                    object_get_typename(obj), name, value);
299         goto out;
300     }
301     nfds->maxlen = value;
302 
303 out:
304     error_propagate(errp, local_err);
305 }
306 
307 static char *file_dump_get_filename(Object *obj, Error **errp)
308 {
309     NetFilterDumpState *nfds = FILTER_DUMP(obj);
310 
311     return g_strdup(nfds->filename);
312 }
313 
314 static void file_dump_set_filename(Object *obj, const char *value, Error **errp)
315 {
316    NetFilterDumpState *nfds = FILTER_DUMP(obj);
317 
318     g_free(nfds->filename);
319     nfds->filename = g_strdup(value);
320 }
321 
322 static void filter_dump_instance_init(Object *obj)
323 {
324     NetFilterDumpState *nfds = FILTER_DUMP(obj);
325 
326     nfds->maxlen = 65536;
327 
328     object_property_add(obj, "maxlen", "int", filter_dump_get_maxlen,
329                         filter_dump_set_maxlen, NULL, NULL, NULL);
330     object_property_add_str(obj, "file", file_dump_get_filename,
331                             file_dump_set_filename, NULL);
332 }
333 
334 static void filter_dump_instance_finalize(Object *obj)
335 {
336     NetFilterDumpState *nfds = FILTER_DUMP(obj);
337 
338     g_free(nfds->filename);
339 }
340 
341 static void filter_dump_class_init(ObjectClass *oc, void *data)
342 {
343     NetFilterClass *nfc = NETFILTER_CLASS(oc);
344 
345     nfc->setup = filter_dump_setup;
346     nfc->cleanup = filter_dump_cleanup;
347     nfc->receive_iov = filter_dump_receive_iov;
348 }
349 
350 static const TypeInfo filter_dump_info = {
351     .name = TYPE_FILTER_DUMP,
352     .parent = TYPE_NETFILTER,
353     .class_init = filter_dump_class_init,
354     .instance_init = filter_dump_instance_init,
355     .instance_finalize = filter_dump_instance_finalize,
356     .instance_size = sizeof(NetFilterDumpState),
357 };
358 
359 static void filter_dump_register_types(void)
360 {
361     type_register_static(&filter_dump_info);
362 }
363 
364 type_init(filter_dump_register_types);
365