xref: /qemu/net/filter-mirror.c (revision e3a6e0da) 
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 
24 #define TYPE_FILTER_MIRROR "filter-mirror"
25 typedef struct MirrorState MirrorState;
26 DECLARE_INSTANCE_CHECKER(MirrorState, FILTER_MIRROR,
27                          TYPE_FILTER_MIRROR)
28 
29 #define TYPE_FILTER_REDIRECTOR "filter-redirector"
30 DECLARE_INSTANCE_CHECKER(MirrorState, FILTER_REDIRECTOR,
31                          TYPE_FILTER_REDIRECTOR)
32 
33 #define REDIRECTOR_MAX_LEN NET_BUFSIZE
34 
35 struct MirrorState {
36     NetFilterState parent_obj;
37     char *indev;
38     char *outdev;
39     CharBackend chr_in;
40     CharBackend chr_out;
41     SocketReadState rs;
42     bool vnet_hdr;
43 };
44 
45 static int filter_send(MirrorState *s,
46                        const struct iovec *iov,
47                        int iovcnt)
48 {
49     NetFilterState *nf = NETFILTER(s);
50     int ret = 0;
51     ssize_t size = 0;
52     uint32_t len = 0;
53     char *buf;
54 
55     size = iov_size(iov, iovcnt);
56     if (!size) {
57         return 0;
58     }
59 
60     len = htonl(size);
61     ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)&len, sizeof(len));
62     if (ret != sizeof(len)) {
63         goto err;
64     }
65 
66     if (s->vnet_hdr) {
67         /*
68          * If vnet_hdr = on, we send vnet header len to make other
69          * module(like colo-compare) know how to parse net
70          * packet correctly.
71          */
72         ssize_t vnet_hdr_len;
73 
74         vnet_hdr_len = nf->netdev->vnet_hdr_len;
75 
76         len = htonl(vnet_hdr_len);
77         ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)&len, sizeof(len));
78         if (ret != sizeof(len)) {
79             goto err;
80         }
81     }
82 
83     buf = g_malloc(size);
84     iov_to_buf(iov, iovcnt, 0, buf, size);
85     ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)buf, size);
86     g_free(buf);
87     if (ret != size) {
88         goto err;
89     }
90 
91     return 0;
92 
93 err:
94     return ret < 0 ? ret : -EIO;
95 }
96 
97 static void redirector_to_filter(NetFilterState *nf,
98                                  const uint8_t *buf,
99                                  int len)
100 {
101     struct iovec iov = {
102         .iov_base = (void *)buf,
103         .iov_len = len,
104     };
105 
106     if (nf->direction == NET_FILTER_DIRECTION_ALL ||
107         nf->direction == NET_FILTER_DIRECTION_TX) {
108         qemu_netfilter_pass_to_next(nf->netdev, 0, &iov, 1, nf);
109     }
110 
111     if (nf->direction == NET_FILTER_DIRECTION_ALL ||
112         nf->direction == NET_FILTER_DIRECTION_RX) {
113         qemu_netfilter_pass_to_next(nf->netdev->peer, 0, &iov, 1, nf);
114      }
115 }
116 
117 static int redirector_chr_can_read(void *opaque)
118 {
119     return REDIRECTOR_MAX_LEN;
120 }
121 
122 static void redirector_chr_read(void *opaque, const uint8_t *buf, int size)
123 {
124     NetFilterState *nf = opaque;
125     MirrorState *s = FILTER_REDIRECTOR(nf);
126     int ret;
127 
128     ret = net_fill_rstate(&s->rs, buf, size);
129 
130     if (ret == -1) {
131         qemu_chr_fe_set_handlers(&s->chr_in, NULL, NULL, NULL,
132                                  NULL, NULL, NULL, true);
133     }
134 }
135 
136 static void redirector_chr_event(void *opaque, QEMUChrEvent event)
137 {
138     NetFilterState *nf = opaque;
139     MirrorState *s = FILTER_REDIRECTOR(nf);
140 
141     switch (event) {
142     case CHR_EVENT_CLOSED:
143         qemu_chr_fe_set_handlers(&s->chr_in, NULL, NULL, NULL,
144                                  NULL, NULL, NULL, true);
145         break;
146     default:
147         break;
148     }
149 }
150 
151 static ssize_t filter_mirror_receive_iov(NetFilterState *nf,
152                                          NetClientState *sender,
153                                          unsigned flags,
154                                          const struct iovec *iov,
155                                          int iovcnt,
156                                          NetPacketSent *sent_cb)
157 {
158     MirrorState *s = FILTER_MIRROR(nf);
159     int ret;
160 
161     ret = filter_send(s, iov, iovcnt);
162     if (ret) {
163         error_report("filter mirror send failed(%s)", strerror(-ret));
164     }
165 
166     /*
167      * we don't hope this error interrupt the normal
168      * path of net packet, so we always return zero.
169      */
170     return 0;
171 }
172 
173 static ssize_t filter_redirector_receive_iov(NetFilterState *nf,
174                                              NetClientState *sender,
175                                              unsigned flags,
176                                              const struct iovec *iov,
177                                              int iovcnt,
178                                              NetPacketSent *sent_cb)
179 {
180     MirrorState *s = FILTER_REDIRECTOR(nf);
181     int ret;
182 
183     if (qemu_chr_fe_backend_connected(&s->chr_out)) {
184         ret = filter_send(s, iov, iovcnt);
185         if (ret) {
186             error_report("filter redirector send failed(%s)", strerror(-ret));
187         }
188         return iov_size(iov, iovcnt);
189     } else {
190         return 0;
191     }
192 }
193 
194 static void filter_mirror_cleanup(NetFilterState *nf)
195 {
196     MirrorState *s = FILTER_MIRROR(nf);
197 
198     qemu_chr_fe_deinit(&s->chr_out, false);
199 }
200 
201 static void filter_redirector_cleanup(NetFilterState *nf)
202 {
203     MirrorState *s = FILTER_REDIRECTOR(nf);
204 
205     qemu_chr_fe_deinit(&s->chr_in, false);
206     qemu_chr_fe_deinit(&s->chr_out, false);
207 }
208 
209 static void filter_mirror_setup(NetFilterState *nf, Error **errp)
210 {
211     MirrorState *s = FILTER_MIRROR(nf);
212     Chardev *chr;
213 
214     if (s->outdev == NULL) {
215         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND, "filter-mirror parameter"\
216                   " 'outdev' cannot be empty");
217         return;
218     }
219 
220     chr = qemu_chr_find(s->outdev);
221     if (chr == NULL) {
222         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
223                   "Device '%s' not found", s->outdev);
224         return;
225     }
226 
227     qemu_chr_fe_init(&s->chr_out, chr, errp);
228 }
229 
230 static void redirector_rs_finalize(SocketReadState *rs)
231 {
232     MirrorState *s = container_of(rs, MirrorState, rs);
233     NetFilterState *nf = NETFILTER(s);
234 
235     redirector_to_filter(nf, rs->buf, rs->packet_len);
236 }
237 
238 static void filter_redirector_setup(NetFilterState *nf, Error **errp)
239 {
240     MirrorState *s = FILTER_REDIRECTOR(nf);
241     Chardev *chr;
242 
243     if (!s->indev && !s->outdev) {
244         error_setg(errp, "filter redirector needs 'indev' or "
245                    "'outdev' at least one property set");
246         return;
247     } else if (s->indev && s->outdev) {
248         if (!strcmp(s->indev, s->outdev)) {
249             error_setg(errp, "'indev' and 'outdev' could not be same "
250                        "for filter redirector");
251             return;
252         }
253     }
254 
255     net_socket_rs_init(&s->rs, redirector_rs_finalize, s->vnet_hdr);
256 
257     if (s->indev) {
258         chr = qemu_chr_find(s->indev);
259         if (chr == NULL) {
260             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
261                       "IN Device '%s' not found", s->indev);
262             return;
263         }
264 
265         if (!qemu_chr_fe_init(&s->chr_in, chr, errp)) {
266             return;
267         }
268 
269         qemu_chr_fe_set_handlers(&s->chr_in, redirector_chr_can_read,
270                                  redirector_chr_read, redirector_chr_event,
271                                  NULL, nf, NULL, true);
272     }
273 
274     if (s->outdev) {
275         chr = qemu_chr_find(s->outdev);
276         if (chr == NULL) {
277             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
278                       "OUT Device '%s' not found", s->outdev);
279             return;
280         }
281         if (!qemu_chr_fe_init(&s->chr_out, chr, errp)) {
282             return;
283         }
284     }
285 }
286 
287 static void filter_mirror_class_init(ObjectClass *oc, void *data)
288 {
289     NetFilterClass *nfc = NETFILTER_CLASS(oc);
290 
291     nfc->setup = filter_mirror_setup;
292     nfc->cleanup = filter_mirror_cleanup;
293     nfc->receive_iov = filter_mirror_receive_iov;
294 }
295 
296 static void filter_redirector_class_init(ObjectClass *oc, void *data)
297 {
298     NetFilterClass *nfc = NETFILTER_CLASS(oc);
299 
300     nfc->setup = filter_redirector_setup;
301     nfc->cleanup = filter_redirector_cleanup;
302     nfc->receive_iov = filter_redirector_receive_iov;
303 }
304 
305 static char *filter_redirector_get_indev(Object *obj, Error **errp)
306 {
307     MirrorState *s = FILTER_REDIRECTOR(obj);
308 
309     return g_strdup(s->indev);
310 }
311 
312 static void filter_redirector_set_indev(Object *obj,
313                                         const char *value,
314                                         Error **errp)
315 {
316     MirrorState *s = FILTER_REDIRECTOR(obj);
317 
318     g_free(s->indev);
319     s->indev = g_strdup(value);
320 }
321 
322 static char *filter_mirror_get_outdev(Object *obj, Error **errp)
323 {
324     MirrorState *s = FILTER_MIRROR(obj);
325 
326     return g_strdup(s->outdev);
327 }
328 
329 static void filter_mirror_set_outdev(Object *obj,
330                                      const char *value,
331                                      Error **errp)
332 {
333     MirrorState *s = FILTER_MIRROR(obj);
334 
335     g_free(s->outdev);
336     s->outdev = g_strdup(value);
337     if (!s->outdev) {
338         error_setg(errp, "filter mirror needs 'outdev' "
339                    "property set");
340         return;
341     }
342 }
343 
344 static bool filter_mirror_get_vnet_hdr(Object *obj, Error **errp)
345 {
346     MirrorState *s = FILTER_MIRROR(obj);
347 
348     return s->vnet_hdr;
349 }
350 
351 static void filter_mirror_set_vnet_hdr(Object *obj, bool value, Error **errp)
352 {
353     MirrorState *s = FILTER_MIRROR(obj);
354 
355     s->vnet_hdr = value;
356 }
357 
358 static char *filter_redirector_get_outdev(Object *obj, Error **errp)
359 {
360     MirrorState *s = FILTER_REDIRECTOR(obj);
361 
362     return g_strdup(s->outdev);
363 }
364 
365 static void filter_redirector_set_outdev(Object *obj,
366                                          const char *value,
367                                          Error **errp)
368 {
369     MirrorState *s = FILTER_REDIRECTOR(obj);
370 
371     g_free(s->outdev);
372     s->outdev = g_strdup(value);
373 }
374 
375 static bool filter_redirector_get_vnet_hdr(Object *obj, Error **errp)
376 {
377     MirrorState *s = FILTER_REDIRECTOR(obj);
378 
379     return s->vnet_hdr;
380 }
381 
382 static void filter_redirector_set_vnet_hdr(Object *obj,
383                                            bool value,
384                                            Error **errp)
385 {
386     MirrorState *s = FILTER_REDIRECTOR(obj);
387 
388     s->vnet_hdr = value;
389 }
390 
391 static void filter_mirror_init(Object *obj)
392 {
393     MirrorState *s = FILTER_MIRROR(obj);
394 
395     object_property_add_str(obj, "outdev", filter_mirror_get_outdev,
396                             filter_mirror_set_outdev);
397 
398     s->vnet_hdr = false;
399     object_property_add_bool(obj, "vnet_hdr_support",
400                              filter_mirror_get_vnet_hdr,
401                              filter_mirror_set_vnet_hdr);
402 }
403 
404 static void filter_redirector_init(Object *obj)
405 {
406     MirrorState *s = FILTER_REDIRECTOR(obj);
407 
408     object_property_add_str(obj, "indev", filter_redirector_get_indev,
409                             filter_redirector_set_indev);
410     object_property_add_str(obj, "outdev", filter_redirector_get_outdev,
411                             filter_redirector_set_outdev);
412 
413     s->vnet_hdr = false;
414     object_property_add_bool(obj, "vnet_hdr_support",
415                              filter_redirector_get_vnet_hdr,
416                              filter_redirector_set_vnet_hdr);
417 }
418 
419 static void filter_mirror_fini(Object *obj)
420 {
421     MirrorState *s = FILTER_MIRROR(obj);
422 
423     g_free(s->outdev);
424 }
425 
426 static void filter_redirector_fini(Object *obj)
427 {
428     MirrorState *s = FILTER_REDIRECTOR(obj);
429 
430     g_free(s->indev);
431     g_free(s->outdev);
432 }
433 
434 static const TypeInfo filter_redirector_info = {
435     .name = TYPE_FILTER_REDIRECTOR,
436     .parent = TYPE_NETFILTER,
437     .class_init = filter_redirector_class_init,
438     .instance_init = filter_redirector_init,
439     .instance_finalize = filter_redirector_fini,
440     .instance_size = sizeof(MirrorState),
441 };
442 
443 static const TypeInfo filter_mirror_info = {
444     .name = TYPE_FILTER_MIRROR,
445     .parent = TYPE_NETFILTER,
446     .class_init = filter_mirror_class_init,
447     .instance_init = filter_mirror_init,
448     .instance_finalize = filter_mirror_fini,
449     .instance_size = sizeof(MirrorState),
450 };
451 
452 static void register_types(void)
453 {
454     type_register_static(&filter_mirror_info);
455     type_register_static(&filter_redirector_info);
456 }
457 
458 type_init(register_types);
459