xref: /openbmc/qemu/net/filter-mirror.c (revision d695918f)
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 "qapi/error.h"
16 #include "qom/object.h"
17 #include "qemu/main-loop.h"
18 #include "qemu/error-report.h"
19 #include "trace.h"
20 #include "chardev/char-fe.h"
21 #include "qemu/iov.h"
22 #include "qemu/sockets.h"
23 #include "block/aio-wait.h"
24 
25 #define TYPE_FILTER_MIRROR "filter-mirror"
26 typedef struct MirrorState MirrorState;
27 DECLARE_INSTANCE_CHECKER(MirrorState, FILTER_MIRROR,
28                          TYPE_FILTER_MIRROR)
29 
30 #define TYPE_FILTER_REDIRECTOR "filter-redirector"
31 DECLARE_INSTANCE_CHECKER(MirrorState, FILTER_REDIRECTOR,
32                          TYPE_FILTER_REDIRECTOR)
33 
34 #define REDIRECTOR_MAX_LEN NET_BUFSIZE
35 
36 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 };
45 
46 typedef struct FilterSendCo {
47     MirrorState *s;
48     char *buf;
49     ssize_t size;
50     bool done;
51     int ret;
52 } FilterSendCo;
53 
54 static int _filter_send(MirrorState *s,
55                        char *buf,
56                        ssize_t size)
57 {
58     NetFilterState *nf = NETFILTER(s);
59     int ret = 0;
60     uint32_t len = 0;
61 
62     len = htonl(size);
63     ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)&len, sizeof(len));
64     if (ret != sizeof(len)) {
65         goto err;
66     }
67 
68     if (s->vnet_hdr) {
69         /*
70          * If vnet_hdr = on, we send vnet header len to make other
71          * module(like colo-compare) know how to parse net
72          * packet correctly.
73          */
74         ssize_t vnet_hdr_len;
75 
76         vnet_hdr_len = nf->netdev->vnet_hdr_len;
77 
78         len = htonl(vnet_hdr_len);
79         ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)&len, sizeof(len));
80         if (ret != sizeof(len)) {
81             goto err;
82         }
83     }
84 
85     ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)buf, size);
86     if (ret != size) {
87         goto err;
88     }
89 
90     return size;
91 
92 err:
93     return ret < 0 ? ret : -EIO;
94 }
95 
96 static void coroutine_fn filter_send_co(void *opaque)
97 {
98     FilterSendCo *data = opaque;
99 
100     data->ret = _filter_send(data->s, data->buf, data->size);
101     data->done = true;
102     g_free(data->buf);
103     aio_wait_kick();
104 }
105 
106 static int filter_send(MirrorState *s,
107                        const struct iovec *iov,
108                        int iovcnt)
109 {
110     ssize_t size = iov_size(iov, iovcnt);
111     char *buf = NULL;
112 
113     if (!size) {
114         return 0;
115     }
116 
117     buf = g_malloc(size);
118     iov_to_buf(iov, iovcnt, 0, buf, size);
119 
120     FilterSendCo data = {
121         .s = s,
122         .size = size,
123         .buf = buf,
124         .ret = 0,
125     };
126 
127     Coroutine *co = qemu_coroutine_create(filter_send_co, &data);
128     qemu_coroutine_enter(co);
129 
130     while (!data.done) {
131         aio_poll(qemu_get_aio_context(), true);
132     }
133 
134     return data.ret;
135 }
136 
137 static void redirector_to_filter(NetFilterState *nf,
138                                  const uint8_t *buf,
139                                  int len)
140 {
141     struct iovec iov = {
142         .iov_base = (void *)buf,
143         .iov_len = len,
144     };
145 
146     if (nf->direction == NET_FILTER_DIRECTION_ALL ||
147         nf->direction == NET_FILTER_DIRECTION_TX) {
148         qemu_netfilter_pass_to_next(nf->netdev, 0, &iov, 1, nf);
149     }
150 
151     if (nf->direction == NET_FILTER_DIRECTION_ALL ||
152         nf->direction == NET_FILTER_DIRECTION_RX) {
153         qemu_netfilter_pass_to_next(nf->netdev->peer, 0, &iov, 1, nf);
154      }
155 }
156 
157 static int redirector_chr_can_read(void *opaque)
158 {
159     return REDIRECTOR_MAX_LEN;
160 }
161 
162 static void redirector_chr_read(void *opaque, const uint8_t *buf, int size)
163 {
164     NetFilterState *nf = opaque;
165     MirrorState *s = FILTER_REDIRECTOR(nf);
166     int ret;
167 
168     ret = net_fill_rstate(&s->rs, buf, size);
169 
170     if (ret == -1) {
171         qemu_chr_fe_set_handlers(&s->chr_in, NULL, NULL, NULL,
172                                  NULL, NULL, NULL, true);
173     }
174 }
175 
176 static void redirector_chr_event(void *opaque, QEMUChrEvent event)
177 {
178     NetFilterState *nf = opaque;
179     MirrorState *s = FILTER_REDIRECTOR(nf);
180 
181     switch (event) {
182     case CHR_EVENT_CLOSED:
183         qemu_chr_fe_set_handlers(&s->chr_in, NULL, NULL, NULL,
184                                  NULL, NULL, NULL, true);
185         break;
186     default:
187         break;
188     }
189 }
190 
191 static ssize_t filter_mirror_receive_iov(NetFilterState *nf,
192                                          NetClientState *sender,
193                                          unsigned flags,
194                                          const struct iovec *iov,
195                                          int iovcnt,
196                                          NetPacketSent *sent_cb)
197 {
198     MirrorState *s = FILTER_MIRROR(nf);
199     int ret;
200 
201     ret = filter_send(s, iov, iovcnt);
202     if (ret < 0) {
203         error_report("filter mirror send failed(%s)", strerror(-ret));
204     }
205 
206     /*
207      * we don't hope this error interrupt the normal
208      * path of net packet, so we always return zero.
209      */
210     return 0;
211 }
212 
213 static ssize_t filter_redirector_receive_iov(NetFilterState *nf,
214                                              NetClientState *sender,
215                                              unsigned flags,
216                                              const struct iovec *iov,
217                                              int iovcnt,
218                                              NetPacketSent *sent_cb)
219 {
220     MirrorState *s = FILTER_REDIRECTOR(nf);
221     int ret;
222 
223     if (qemu_chr_fe_backend_connected(&s->chr_out)) {
224         ret = filter_send(s, iov, iovcnt);
225         if (ret < 0) {
226             error_report("filter redirector send failed(%s)", strerror(-ret));
227         }
228         return ret;
229     } else {
230         return 0;
231     }
232 }
233 
234 static void filter_mirror_cleanup(NetFilterState *nf)
235 {
236     MirrorState *s = FILTER_MIRROR(nf);
237 
238     qemu_chr_fe_deinit(&s->chr_out, false);
239 }
240 
241 static void filter_redirector_cleanup(NetFilterState *nf)
242 {
243     MirrorState *s = FILTER_REDIRECTOR(nf);
244 
245     qemu_chr_fe_deinit(&s->chr_in, false);
246     qemu_chr_fe_deinit(&s->chr_out, false);
247 }
248 
249 static void filter_mirror_setup(NetFilterState *nf, Error **errp)
250 {
251     MirrorState *s = FILTER_MIRROR(nf);
252     Chardev *chr;
253 
254     if (s->outdev == NULL) {
255         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND, "filter-mirror parameter"\
256                   " 'outdev' cannot be empty");
257         return;
258     }
259 
260     chr = qemu_chr_find(s->outdev);
261     if (chr == NULL) {
262         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
263                   "Device '%s' not found", s->outdev);
264         return;
265     }
266 
267     qemu_chr_fe_init(&s->chr_out, chr, errp);
268 }
269 
270 static void redirector_rs_finalize(SocketReadState *rs)
271 {
272     MirrorState *s = container_of(rs, MirrorState, rs);
273     NetFilterState *nf = NETFILTER(s);
274 
275     redirector_to_filter(nf, rs->buf, rs->packet_len);
276 }
277 
278 static void filter_redirector_setup(NetFilterState *nf, Error **errp)
279 {
280     MirrorState *s = FILTER_REDIRECTOR(nf);
281     Chardev *chr;
282 
283     if (!s->indev && !s->outdev) {
284         error_setg(errp, "filter redirector needs 'indev' or "
285                    "'outdev' at least one property set");
286         return;
287     } else if (s->indev && s->outdev) {
288         if (!strcmp(s->indev, s->outdev)) {
289             error_setg(errp, "'indev' and 'outdev' could not be same "
290                        "for filter redirector");
291             return;
292         }
293     }
294 
295     net_socket_rs_init(&s->rs, redirector_rs_finalize, s->vnet_hdr);
296 
297     if (s->indev) {
298         chr = qemu_chr_find(s->indev);
299         if (chr == NULL) {
300             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
301                       "IN Device '%s' not found", s->indev);
302             return;
303         }
304 
305         if (!qemu_chr_fe_init(&s->chr_in, chr, errp)) {
306             return;
307         }
308 
309         qemu_chr_fe_set_handlers(&s->chr_in, redirector_chr_can_read,
310                                  redirector_chr_read, redirector_chr_event,
311                                  NULL, nf, NULL, true);
312     }
313 
314     if (s->outdev) {
315         chr = qemu_chr_find(s->outdev);
316         if (chr == NULL) {
317             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
318                       "OUT Device '%s' not found", s->outdev);
319             return;
320         }
321         if (!qemu_chr_fe_init(&s->chr_out, chr, errp)) {
322             return;
323         }
324     }
325 }
326 
327 static char *filter_redirector_get_indev(Object *obj, Error **errp)
328 {
329     MirrorState *s = FILTER_REDIRECTOR(obj);
330 
331     return g_strdup(s->indev);
332 }
333 
334 static void filter_redirector_set_indev(Object *obj,
335                                         const char *value,
336                                         Error **errp)
337 {
338     MirrorState *s = FILTER_REDIRECTOR(obj);
339 
340     g_free(s->indev);
341     s->indev = g_strdup(value);
342 }
343 
344 static char *filter_mirror_get_outdev(Object *obj, Error **errp)
345 {
346     MirrorState *s = FILTER_MIRROR(obj);
347 
348     return g_strdup(s->outdev);
349 }
350 
351 static void filter_mirror_set_outdev(Object *obj,
352                                      const char *value,
353                                      Error **errp)
354 {
355     MirrorState *s = FILTER_MIRROR(obj);
356 
357     g_free(s->outdev);
358     s->outdev = g_strdup(value);
359     if (!s->outdev) {
360         error_setg(errp, "filter mirror needs 'outdev' "
361                    "property set");
362         return;
363     }
364 }
365 
366 static bool filter_mirror_get_vnet_hdr(Object *obj, Error **errp)
367 {
368     MirrorState *s = FILTER_MIRROR(obj);
369 
370     return s->vnet_hdr;
371 }
372 
373 static void filter_mirror_set_vnet_hdr(Object *obj, bool value, Error **errp)
374 {
375     MirrorState *s = FILTER_MIRROR(obj);
376 
377     s->vnet_hdr = value;
378 }
379 
380 static char *filter_redirector_get_outdev(Object *obj, Error **errp)
381 {
382     MirrorState *s = FILTER_REDIRECTOR(obj);
383 
384     return g_strdup(s->outdev);
385 }
386 
387 static void filter_redirector_set_outdev(Object *obj,
388                                          const char *value,
389                                          Error **errp)
390 {
391     MirrorState *s = FILTER_REDIRECTOR(obj);
392 
393     g_free(s->outdev);
394     s->outdev = g_strdup(value);
395 }
396 
397 static bool filter_redirector_get_vnet_hdr(Object *obj, Error **errp)
398 {
399     MirrorState *s = FILTER_REDIRECTOR(obj);
400 
401     return s->vnet_hdr;
402 }
403 
404 static void filter_redirector_set_vnet_hdr(Object *obj,
405                                            bool value,
406                                            Error **errp)
407 {
408     MirrorState *s = FILTER_REDIRECTOR(obj);
409 
410     s->vnet_hdr = value;
411 }
412 
413 static void filter_mirror_class_init(ObjectClass *oc, void *data)
414 {
415     NetFilterClass *nfc = NETFILTER_CLASS(oc);
416 
417     object_class_property_add_str(oc, "outdev", filter_mirror_get_outdev,
418                                   filter_mirror_set_outdev);
419     object_class_property_add_bool(oc, "vnet_hdr_support",
420                                    filter_mirror_get_vnet_hdr,
421                                    filter_mirror_set_vnet_hdr);
422 
423     nfc->setup = filter_mirror_setup;
424     nfc->cleanup = filter_mirror_cleanup;
425     nfc->receive_iov = filter_mirror_receive_iov;
426 }
427 
428 static void filter_redirector_class_init(ObjectClass *oc, void *data)
429 {
430     NetFilterClass *nfc = NETFILTER_CLASS(oc);
431 
432     object_class_property_add_str(oc, "indev", filter_redirector_get_indev,
433                                   filter_redirector_set_indev);
434     object_class_property_add_str(oc, "outdev", filter_redirector_get_outdev,
435                                   filter_redirector_set_outdev);
436     object_class_property_add_bool(oc, "vnet_hdr_support",
437                                    filter_redirector_get_vnet_hdr,
438                                    filter_redirector_set_vnet_hdr);
439 
440     nfc->setup = filter_redirector_setup;
441     nfc->cleanup = filter_redirector_cleanup;
442     nfc->receive_iov = filter_redirector_receive_iov;
443 }
444 
445 static void filter_mirror_init(Object *obj)
446 {
447     MirrorState *s = FILTER_MIRROR(obj);
448 
449     s->vnet_hdr = false;
450 }
451 
452 static void filter_redirector_init(Object *obj)
453 {
454     MirrorState *s = FILTER_REDIRECTOR(obj);
455 
456     s->vnet_hdr = false;
457 }
458 
459 static void filter_mirror_fini(Object *obj)
460 {
461     MirrorState *s = FILTER_MIRROR(obj);
462 
463     g_free(s->outdev);
464 }
465 
466 static void filter_redirector_fini(Object *obj)
467 {
468     MirrorState *s = FILTER_REDIRECTOR(obj);
469 
470     g_free(s->indev);
471     g_free(s->outdev);
472 }
473 
474 static const TypeInfo filter_redirector_info = {
475     .name = TYPE_FILTER_REDIRECTOR,
476     .parent = TYPE_NETFILTER,
477     .class_init = filter_redirector_class_init,
478     .instance_init = filter_redirector_init,
479     .instance_finalize = filter_redirector_fini,
480     .instance_size = sizeof(MirrorState),
481 };
482 
483 static const TypeInfo filter_mirror_info = {
484     .name = TYPE_FILTER_MIRROR,
485     .parent = TYPE_NETFILTER,
486     .class_init = filter_mirror_class_init,
487     .instance_init = filter_mirror_init,
488     .instance_finalize = filter_mirror_fini,
489     .instance_size = sizeof(MirrorState),
490 };
491 
492 static void register_types(void)
493 {
494     type_register_static(&filter_mirror_info);
495     type_register_static(&filter_redirector_info);
496 }
497 
498 type_init(register_types);
499