xref: /openbmc/qemu/net/filter-mirror.c (revision 922a01a013d2270682a188258cbccacfecf8129c)
1 /*
2  * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
3  * Copyright (c) 2016 FUJITSU LIMITED
4  * Copyright (c) 2016 Intel Corporation
5  *
6  * Author: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
7  *
8  * This work is licensed under the terms of the GNU GPL, version 2 or
9  * later.  See the COPYING file in the top-level directory.
10  */
11 
12 #include "qemu/osdep.h"
13 #include "net/filter.h"
14 #include "net/net.h"
15 #include "qemu-common.h"
16 #include "qapi/error.h"
17 #include "qapi-visit.h"
18 #include "qom/object.h"
19 #include "qemu/main-loop.h"
20 #include "qemu/error-report.h"
21 #include "trace.h"
22 #include "chardev/char-fe.h"
23 #include "qemu/iov.h"
24 #include "qemu/sockets.h"
25 
26 #define FILTER_MIRROR(obj) \
27     OBJECT_CHECK(MirrorState, (obj), TYPE_FILTER_MIRROR)
28 
29 #define FILTER_REDIRECTOR(obj) \
30     OBJECT_CHECK(MirrorState, (obj), TYPE_FILTER_REDIRECTOR)
31 
32 #define TYPE_FILTER_MIRROR "filter-mirror"
33 #define TYPE_FILTER_REDIRECTOR "filter-redirector"
34 #define REDIRECTOR_MAX_LEN NET_BUFSIZE
35 
36 typedef struct MirrorState {
37     NetFilterState parent_obj;
38     char *indev;
39     char *outdev;
40     CharBackend chr_in;
41     CharBackend chr_out;
42     SocketReadState rs;
43     bool vnet_hdr;
44 } MirrorState;
45 
46 static int filter_send(MirrorState *s,
47                        const struct iovec *iov,
48                        int iovcnt)
49 {
50     NetFilterState *nf = NETFILTER(s);
51     int ret = 0;
52     ssize_t size = 0;
53     uint32_t len = 0;
54     char *buf;
55 
56     size = iov_size(iov, iovcnt);
57     if (!size) {
58         return 0;
59     }
60 
61     len = htonl(size);
62     ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)&len, sizeof(len));
63     if (ret != sizeof(len)) {
64         goto err;
65     }
66 
67     if (s->vnet_hdr) {
68         /*
69          * If vnet_hdr = on, we send vnet header len to make other
70          * module(like colo-compare) know how to parse net
71          * packet correctly.
72          */
73         ssize_t vnet_hdr_len;
74 
75         vnet_hdr_len = nf->netdev->vnet_hdr_len;
76 
77         len = htonl(vnet_hdr_len);
78         ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)&len, sizeof(len));
79         if (ret != sizeof(len)) {
80             goto err;
81         }
82     }
83 
84     buf = g_malloc(size);
85     iov_to_buf(iov, iovcnt, 0, buf, size);
86     ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)buf, size);
87     g_free(buf);
88     if (ret != size) {
89         goto err;
90     }
91 
92     return 0;
93 
94 err:
95     return ret < 0 ? ret : -EIO;
96 }
97 
98 static void redirector_to_filter(NetFilterState *nf,
99                                  const uint8_t *buf,
100                                  int len)
101 {
102     struct iovec iov = {
103         .iov_base = (void *)buf,
104         .iov_len = len,
105     };
106 
107     if (nf->direction == NET_FILTER_DIRECTION_ALL ||
108         nf->direction == NET_FILTER_DIRECTION_TX) {
109         qemu_netfilter_pass_to_next(nf->netdev, 0, &iov, 1, nf);
110     }
111 
112     if (nf->direction == NET_FILTER_DIRECTION_ALL ||
113         nf->direction == NET_FILTER_DIRECTION_RX) {
114         qemu_netfilter_pass_to_next(nf->netdev->peer, 0, &iov, 1, nf);
115      }
116 }
117 
118 static int redirector_chr_can_read(void *opaque)
119 {
120     return REDIRECTOR_MAX_LEN;
121 }
122 
123 static void redirector_chr_read(void *opaque, const uint8_t *buf, int size)
124 {
125     NetFilterState *nf = opaque;
126     MirrorState *s = FILTER_REDIRECTOR(nf);
127     int ret;
128 
129     ret = net_fill_rstate(&s->rs, buf, size);
130 
131     if (ret == -1) {
132         qemu_chr_fe_set_handlers(&s->chr_in, NULL, NULL, NULL,
133                                  NULL, NULL, NULL, true);
134     }
135 }
136 
137 static void redirector_chr_event(void *opaque, int event)
138 {
139     NetFilterState *nf = opaque;
140     MirrorState *s = FILTER_REDIRECTOR(nf);
141 
142     switch (event) {
143     case CHR_EVENT_CLOSED:
144         qemu_chr_fe_set_handlers(&s->chr_in, NULL, NULL, NULL,
145                                  NULL, NULL, NULL, true);
146         break;
147     default:
148         break;
149     }
150 }
151 
152 static ssize_t filter_mirror_receive_iov(NetFilterState *nf,
153                                          NetClientState *sender,
154                                          unsigned flags,
155                                          const struct iovec *iov,
156                                          int iovcnt,
157                                          NetPacketSent *sent_cb)
158 {
159     MirrorState *s = FILTER_MIRROR(nf);
160     int ret;
161 
162     ret = filter_send(s, iov, iovcnt);
163     if (ret) {
164         error_report("filter mirror send failed(%s)", strerror(-ret));
165     }
166 
167     /*
168      * we don't hope this error interrupt the normal
169      * path of net packet, so we always return zero.
170      */
171     return 0;
172 }
173 
174 static ssize_t filter_redirector_receive_iov(NetFilterState *nf,
175                                              NetClientState *sender,
176                                              unsigned flags,
177                                              const struct iovec *iov,
178                                              int iovcnt,
179                                              NetPacketSent *sent_cb)
180 {
181     MirrorState *s = FILTER_REDIRECTOR(nf);
182     int ret;
183 
184     if (qemu_chr_fe_backend_connected(&s->chr_out)) {
185         ret = filter_send(s, iov, iovcnt);
186         if (ret) {
187             error_report("filter redirector send failed(%s)", strerror(-ret));
188         }
189         return iov_size(iov, iovcnt);
190     } else {
191         return 0;
192     }
193 }
194 
195 static void filter_mirror_cleanup(NetFilterState *nf)
196 {
197     MirrorState *s = FILTER_MIRROR(nf);
198 
199     qemu_chr_fe_deinit(&s->chr_out, false);
200 }
201 
202 static void filter_redirector_cleanup(NetFilterState *nf)
203 {
204     MirrorState *s = FILTER_REDIRECTOR(nf);
205 
206     qemu_chr_fe_deinit(&s->chr_in, false);
207     qemu_chr_fe_deinit(&s->chr_out, false);
208 }
209 
210 static void filter_mirror_setup(NetFilterState *nf, Error **errp)
211 {
212     MirrorState *s = FILTER_MIRROR(nf);
213     Chardev *chr;
214 
215     if (s->outdev == NULL) {
216         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND, "filter-mirror parameter"\
217                   " 'outdev' cannot be empty");
218         return;
219     }
220 
221     chr = qemu_chr_find(s->outdev);
222     if (chr == NULL) {
223         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
224                   "Device '%s' not found", s->outdev);
225         return;
226     }
227 
228     qemu_chr_fe_init(&s->chr_out, chr, errp);
229 }
230 
231 static void redirector_rs_finalize(SocketReadState *rs)
232 {
233     MirrorState *s = container_of(rs, MirrorState, rs);
234     NetFilterState *nf = NETFILTER(s);
235 
236     redirector_to_filter(nf, rs->buf, rs->packet_len);
237 }
238 
239 static void filter_redirector_setup(NetFilterState *nf, Error **errp)
240 {
241     MirrorState *s = FILTER_REDIRECTOR(nf);
242     Chardev *chr;
243 
244     if (!s->indev && !s->outdev) {
245         error_setg(errp, "filter redirector needs 'indev' or "
246                    "'outdev' at least one property set");
247         return;
248     } else if (s->indev && s->outdev) {
249         if (!strcmp(s->indev, s->outdev)) {
250             error_setg(errp, "'indev' and 'outdev' could not be same "
251                        "for filter redirector");
252             return;
253         }
254     }
255 
256     net_socket_rs_init(&s->rs, redirector_rs_finalize, s->vnet_hdr);
257 
258     if (s->indev) {
259         chr = qemu_chr_find(s->indev);
260         if (chr == NULL) {
261             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
262                       "IN Device '%s' not found", s->indev);
263             return;
264         }
265 
266         if (!qemu_chr_fe_init(&s->chr_in, chr, errp)) {
267             return;
268         }
269 
270         qemu_chr_fe_set_handlers(&s->chr_in, redirector_chr_can_read,
271                                  redirector_chr_read, redirector_chr_event,
272                                  NULL, nf, NULL, true);
273     }
274 
275     if (s->outdev) {
276         chr = qemu_chr_find(s->outdev);
277         if (chr == NULL) {
278             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
279                       "OUT Device '%s' not found", s->outdev);
280             return;
281         }
282         if (!qemu_chr_fe_init(&s->chr_out, chr, errp)) {
283             return;
284         }
285     }
286 }
287 
288 static void filter_mirror_class_init(ObjectClass *oc, void *data)
289 {
290     NetFilterClass *nfc = NETFILTER_CLASS(oc);
291 
292     nfc->setup = filter_mirror_setup;
293     nfc->cleanup = filter_mirror_cleanup;
294     nfc->receive_iov = filter_mirror_receive_iov;
295 }
296 
297 static void filter_redirector_class_init(ObjectClass *oc, void *data)
298 {
299     NetFilterClass *nfc = NETFILTER_CLASS(oc);
300 
301     nfc->setup = filter_redirector_setup;
302     nfc->cleanup = filter_redirector_cleanup;
303     nfc->receive_iov = filter_redirector_receive_iov;
304 }
305 
306 static char *filter_redirector_get_indev(Object *obj, Error **errp)
307 {
308     MirrorState *s = FILTER_REDIRECTOR(obj);
309 
310     return g_strdup(s->indev);
311 }
312 
313 static void filter_redirector_set_indev(Object *obj,
314                                         const char *value,
315                                         Error **errp)
316 {
317     MirrorState *s = FILTER_REDIRECTOR(obj);
318 
319     g_free(s->indev);
320     s->indev = g_strdup(value);
321 }
322 
323 static char *filter_mirror_get_outdev(Object *obj, Error **errp)
324 {
325     MirrorState *s = FILTER_MIRROR(obj);
326 
327     return g_strdup(s->outdev);
328 }
329 
330 static void filter_mirror_set_outdev(Object *obj,
331                                      const char *value,
332                                      Error **errp)
333 {
334     MirrorState *s = FILTER_MIRROR(obj);
335 
336     g_free(s->outdev);
337     s->outdev = g_strdup(value);
338     if (!s->outdev) {
339         error_setg(errp, "filter mirror needs 'outdev' "
340                    "property set");
341         return;
342     }
343 }
344 
345 static bool filter_mirror_get_vnet_hdr(Object *obj, Error **errp)
346 {
347     MirrorState *s = FILTER_MIRROR(obj);
348 
349     return s->vnet_hdr;
350 }
351 
352 static void filter_mirror_set_vnet_hdr(Object *obj, bool value, Error **errp)
353 {
354     MirrorState *s = FILTER_MIRROR(obj);
355 
356     s->vnet_hdr = value;
357 }
358 
359 static char *filter_redirector_get_outdev(Object *obj, Error **errp)
360 {
361     MirrorState *s = FILTER_REDIRECTOR(obj);
362 
363     return g_strdup(s->outdev);
364 }
365 
366 static void filter_redirector_set_outdev(Object *obj,
367                                          const char *value,
368                                          Error **errp)
369 {
370     MirrorState *s = FILTER_REDIRECTOR(obj);
371 
372     g_free(s->outdev);
373     s->outdev = g_strdup(value);
374 }
375 
376 static bool filter_redirector_get_vnet_hdr(Object *obj, Error **errp)
377 {
378     MirrorState *s = FILTER_REDIRECTOR(obj);
379 
380     return s->vnet_hdr;
381 }
382 
383 static void filter_redirector_set_vnet_hdr(Object *obj,
384                                            bool value,
385                                            Error **errp)
386 {
387     MirrorState *s = FILTER_REDIRECTOR(obj);
388 
389     s->vnet_hdr = value;
390 }
391 
392 static void filter_mirror_init(Object *obj)
393 {
394     MirrorState *s = FILTER_MIRROR(obj);
395 
396     object_property_add_str(obj, "outdev", filter_mirror_get_outdev,
397                             filter_mirror_set_outdev, NULL);
398 
399     s->vnet_hdr = false;
400     object_property_add_bool(obj, "vnet_hdr_support",
401                              filter_mirror_get_vnet_hdr,
402                              filter_mirror_set_vnet_hdr, NULL);
403 }
404 
405 static void filter_redirector_init(Object *obj)
406 {
407     MirrorState *s = FILTER_REDIRECTOR(obj);
408 
409     object_property_add_str(obj, "indev", filter_redirector_get_indev,
410                             filter_redirector_set_indev, NULL);
411     object_property_add_str(obj, "outdev", filter_redirector_get_outdev,
412                             filter_redirector_set_outdev, NULL);
413 
414     s->vnet_hdr = false;
415     object_property_add_bool(obj, "vnet_hdr_support",
416                              filter_redirector_get_vnet_hdr,
417                              filter_redirector_set_vnet_hdr, NULL);
418 }
419 
420 static void filter_mirror_fini(Object *obj)
421 {
422     MirrorState *s = FILTER_MIRROR(obj);
423 
424     g_free(s->outdev);
425 }
426 
427 static void filter_redirector_fini(Object *obj)
428 {
429     MirrorState *s = FILTER_REDIRECTOR(obj);
430 
431     g_free(s->indev);
432     g_free(s->outdev);
433 }
434 
435 static const TypeInfo filter_redirector_info = {
436     .name = TYPE_FILTER_REDIRECTOR,
437     .parent = TYPE_NETFILTER,
438     .class_init = filter_redirector_class_init,
439     .instance_init = filter_redirector_init,
440     .instance_finalize = filter_redirector_fini,
441     .instance_size = sizeof(MirrorState),
442 };
443 
444 static const TypeInfo filter_mirror_info = {
445     .name = TYPE_FILTER_MIRROR,
446     .parent = TYPE_NETFILTER,
447     .class_init = filter_mirror_class_init,
448     .instance_init = filter_mirror_init,
449     .instance_finalize = filter_mirror_fini,
450     .instance_size = sizeof(MirrorState),
451 };
452 
453 static void register_types(void)
454 {
455     type_register_static(&filter_mirror_info);
456     type_register_static(&filter_redirector_info);
457 }
458 
459 type_init(register_types);
460