xref: /openbmc/qemu/net/filter-mirror.c (revision ccb23709) 
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 FILTER_MIRROR(obj) \
25     OBJECT_CHECK(MirrorState, (obj), TYPE_FILTER_MIRROR)
26 
27 #define FILTER_REDIRECTOR(obj) \
28     OBJECT_CHECK(MirrorState, (obj), TYPE_FILTER_REDIRECTOR)
29 
30 #define TYPE_FILTER_MIRROR "filter-mirror"
31 #define TYPE_FILTER_REDIRECTOR "filter-redirector"
32 #define REDIRECTOR_MAX_LEN NET_BUFSIZE
33 
34 typedef struct MirrorState {
35     NetFilterState parent_obj;
36     char *indev;
37     char *outdev;
38     CharBackend chr_in;
39     CharBackend chr_out;
40     SocketReadState rs;
41     bool vnet_hdr;
42 } MirrorState;
43 
44 static int filter_send(MirrorState *s,
45                        const struct iovec *iov,
46                        int iovcnt)
47 {
48     NetFilterState *nf = NETFILTER(s);
49     int ret = 0;
50     ssize_t size = 0;
51     uint32_t len = 0;
52     char *buf;
53 
54     size = iov_size(iov, iovcnt);
55     if (!size) {
56         return 0;
57     }
58 
59     len = htonl(size);
60     ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)&len, sizeof(len));
61     if (ret != sizeof(len)) {
62         goto err;
63     }
64 
65     if (s->vnet_hdr) {
66         /*
67          * If vnet_hdr = on, we send vnet header len to make other
68          * module(like colo-compare) know how to parse net
69          * packet correctly.
70          */
71         ssize_t vnet_hdr_len;
72 
73         vnet_hdr_len = nf->netdev->vnet_hdr_len;
74 
75         len = htonl(vnet_hdr_len);
76         ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)&len, sizeof(len));
77         if (ret != sizeof(len)) {
78             goto err;
79         }
80     }
81 
82     buf = g_malloc(size);
83     iov_to_buf(iov, iovcnt, 0, buf, size);
84     ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)buf, size);
85     g_free(buf);
86     if (ret != size) {
87         goto err;
88     }
89 
90     return 0;
91 
92 err:
93     return ret < 0 ? ret : -EIO;
94 }
95 
96 static void redirector_to_filter(NetFilterState *nf,
97                                  const uint8_t *buf,
98                                  int len)
99 {
100     struct iovec iov = {
101         .iov_base = (void *)buf,
102         .iov_len = len,
103     };
104 
105     if (nf->direction == NET_FILTER_DIRECTION_ALL ||
106         nf->direction == NET_FILTER_DIRECTION_TX) {
107         qemu_netfilter_pass_to_next(nf->netdev, 0, &iov, 1, nf);
108     }
109 
110     if (nf->direction == NET_FILTER_DIRECTION_ALL ||
111         nf->direction == NET_FILTER_DIRECTION_RX) {
112         qemu_netfilter_pass_to_next(nf->netdev->peer, 0, &iov, 1, nf);
113      }
114 }
115 
116 static int redirector_chr_can_read(void *opaque)
117 {
118     return REDIRECTOR_MAX_LEN;
119 }
120 
121 static void redirector_chr_read(void *opaque, const uint8_t *buf, int size)
122 {
123     NetFilterState *nf = opaque;
124     MirrorState *s = FILTER_REDIRECTOR(nf);
125     int ret;
126 
127     ret = net_fill_rstate(&s->rs, buf, size);
128 
129     if (ret == -1) {
130         qemu_chr_fe_set_handlers(&s->chr_in, NULL, NULL, NULL,
131                                  NULL, NULL, NULL, true);
132     }
133 }
134 
135 static void redirector_chr_event(void *opaque, QEMUChrEvent event)
136 {
137     NetFilterState *nf = opaque;
138     MirrorState *s = FILTER_REDIRECTOR(nf);
139 
140     switch (event) {
141     case CHR_EVENT_CLOSED:
142         qemu_chr_fe_set_handlers(&s->chr_in, NULL, NULL, NULL,
143                                  NULL, NULL, NULL, true);
144         break;
145     default:
146         break;
147     }
148 }
149 
150 static ssize_t filter_mirror_receive_iov(NetFilterState *nf,
151                                          NetClientState *sender,
152                                          unsigned flags,
153                                          const struct iovec *iov,
154                                          int iovcnt,
155                                          NetPacketSent *sent_cb)
156 {
157     MirrorState *s = FILTER_MIRROR(nf);
158     int ret;
159 
160     ret = filter_send(s, iov, iovcnt);
161     if (ret) {
162         error_report("filter mirror send failed(%s)", strerror(-ret));
163     }
164 
165     /*
166      * we don't hope this error interrupt the normal
167      * path of net packet, so we always return zero.
168      */
169     return 0;
170 }
171 
172 static ssize_t filter_redirector_receive_iov(NetFilterState *nf,
173                                              NetClientState *sender,
174                                              unsigned flags,
175                                              const struct iovec *iov,
176                                              int iovcnt,
177                                              NetPacketSent *sent_cb)
178 {
179     MirrorState *s = FILTER_REDIRECTOR(nf);
180     int ret;
181 
182     if (qemu_chr_fe_backend_connected(&s->chr_out)) {
183         ret = filter_send(s, iov, iovcnt);
184         if (ret) {
185             error_report("filter redirector send failed(%s)", strerror(-ret));
186         }
187         return iov_size(iov, iovcnt);
188     } else {
189         return 0;
190     }
191 }
192 
193 static void filter_mirror_cleanup(NetFilterState *nf)
194 {
195     MirrorState *s = FILTER_MIRROR(nf);
196 
197     qemu_chr_fe_deinit(&s->chr_out, false);
198 }
199 
200 static void filter_redirector_cleanup(NetFilterState *nf)
201 {
202     MirrorState *s = FILTER_REDIRECTOR(nf);
203 
204     qemu_chr_fe_deinit(&s->chr_in, false);
205     qemu_chr_fe_deinit(&s->chr_out, false);
206 }
207 
208 static void filter_mirror_setup(NetFilterState *nf, Error **errp)
209 {
210     MirrorState *s = FILTER_MIRROR(nf);
211     Chardev *chr;
212 
213     if (s->outdev == NULL) {
214         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND, "filter-mirror parameter"\
215                   " 'outdev' cannot be empty");
216         return;
217     }
218 
219     chr = qemu_chr_find(s->outdev);
220     if (chr == NULL) {
221         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
222                   "Device '%s' not found", s->outdev);
223         return;
224     }
225 
226     qemu_chr_fe_init(&s->chr_out, chr, errp);
227 }
228 
229 static void redirector_rs_finalize(SocketReadState *rs)
230 {
231     MirrorState *s = container_of(rs, MirrorState, rs);
232     NetFilterState *nf = NETFILTER(s);
233 
234     redirector_to_filter(nf, rs->buf, rs->packet_len);
235 }
236 
237 static void filter_redirector_setup(NetFilterState *nf, Error **errp)
238 {
239     MirrorState *s = FILTER_REDIRECTOR(nf);
240     Chardev *chr;
241 
242     if (!s->indev && !s->outdev) {
243         error_setg(errp, "filter redirector needs 'indev' or "
244                    "'outdev' at least one property set");
245         return;
246     } else if (s->indev && s->outdev) {
247         if (!strcmp(s->indev, s->outdev)) {
248             error_setg(errp, "'indev' and 'outdev' could not be same "
249                        "for filter redirector");
250             return;
251         }
252     }
253 
254     net_socket_rs_init(&s->rs, redirector_rs_finalize, s->vnet_hdr);
255 
256     if (s->indev) {
257         chr = qemu_chr_find(s->indev);
258         if (chr == NULL) {
259             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
260                       "IN Device '%s' not found", s->indev);
261             return;
262         }
263 
264         if (!qemu_chr_fe_init(&s->chr_in, chr, errp)) {
265             return;
266         }
267 
268         qemu_chr_fe_set_handlers(&s->chr_in, redirector_chr_can_read,
269                                  redirector_chr_read, redirector_chr_event,
270                                  NULL, nf, NULL, true);
271     }
272 
273     if (s->outdev) {
274         chr = qemu_chr_find(s->outdev);
275         if (chr == NULL) {
276             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
277                       "OUT Device '%s' not found", s->outdev);
278             return;
279         }
280         if (!qemu_chr_fe_init(&s->chr_out, chr, errp)) {
281             return;
282         }
283     }
284 }
285 
286 static void filter_mirror_class_init(ObjectClass *oc, void *data)
287 {
288     NetFilterClass *nfc = NETFILTER_CLASS(oc);
289 
290     nfc->setup = filter_mirror_setup;
291     nfc->cleanup = filter_mirror_cleanup;
292     nfc->receive_iov = filter_mirror_receive_iov;
293 }
294 
295 static void filter_redirector_class_init(ObjectClass *oc, void *data)
296 {
297     NetFilterClass *nfc = NETFILTER_CLASS(oc);
298 
299     nfc->setup = filter_redirector_setup;
300     nfc->cleanup = filter_redirector_cleanup;
301     nfc->receive_iov = filter_redirector_receive_iov;
302 }
303 
304 static char *filter_redirector_get_indev(Object *obj, Error **errp)
305 {
306     MirrorState *s = FILTER_REDIRECTOR(obj);
307 
308     return g_strdup(s->indev);
309 }
310 
311 static void filter_redirector_set_indev(Object *obj,
312                                         const char *value,
313                                         Error **errp)
314 {
315     MirrorState *s = FILTER_REDIRECTOR(obj);
316 
317     g_free(s->indev);
318     s->indev = g_strdup(value);
319 }
320 
321 static char *filter_mirror_get_outdev(Object *obj, Error **errp)
322 {
323     MirrorState *s = FILTER_MIRROR(obj);
324 
325     return g_strdup(s->outdev);
326 }
327 
328 static void filter_mirror_set_outdev(Object *obj,
329                                      const char *value,
330                                      Error **errp)
331 {
332     MirrorState *s = FILTER_MIRROR(obj);
333 
334     g_free(s->outdev);
335     s->outdev = g_strdup(value);
336     if (!s->outdev) {
337         error_setg(errp, "filter mirror needs 'outdev' "
338                    "property set");
339         return;
340     }
341 }
342 
343 static bool filter_mirror_get_vnet_hdr(Object *obj, Error **errp)
344 {
345     MirrorState *s = FILTER_MIRROR(obj);
346 
347     return s->vnet_hdr;
348 }
349 
350 static void filter_mirror_set_vnet_hdr(Object *obj, bool value, Error **errp)
351 {
352     MirrorState *s = FILTER_MIRROR(obj);
353 
354     s->vnet_hdr = value;
355 }
356 
357 static char *filter_redirector_get_outdev(Object *obj, Error **errp)
358 {
359     MirrorState *s = FILTER_REDIRECTOR(obj);
360 
361     return g_strdup(s->outdev);
362 }
363 
364 static void filter_redirector_set_outdev(Object *obj,
365                                          const char *value,
366                                          Error **errp)
367 {
368     MirrorState *s = FILTER_REDIRECTOR(obj);
369 
370     g_free(s->outdev);
371     s->outdev = g_strdup(value);
372 }
373 
374 static bool filter_redirector_get_vnet_hdr(Object *obj, Error **errp)
375 {
376     MirrorState *s = FILTER_REDIRECTOR(obj);
377 
378     return s->vnet_hdr;
379 }
380 
381 static void filter_redirector_set_vnet_hdr(Object *obj,
382                                            bool value,
383                                            Error **errp)
384 {
385     MirrorState *s = FILTER_REDIRECTOR(obj);
386 
387     s->vnet_hdr = value;
388 }
389 
390 static void filter_mirror_init(Object *obj)
391 {
392     MirrorState *s = FILTER_MIRROR(obj);
393 
394     object_property_add_str(obj, "outdev", filter_mirror_get_outdev,
395                             filter_mirror_set_outdev);
396 
397     s->vnet_hdr = false;
398     object_property_add_bool(obj, "vnet_hdr_support",
399                              filter_mirror_get_vnet_hdr,
400                              filter_mirror_set_vnet_hdr);
401 }
402 
403 static void filter_redirector_init(Object *obj)
404 {
405     MirrorState *s = FILTER_REDIRECTOR(obj);
406 
407     object_property_add_str(obj, "indev", filter_redirector_get_indev,
408                             filter_redirector_set_indev);
409     object_property_add_str(obj, "outdev", filter_redirector_get_outdev,
410                             filter_redirector_set_outdev);
411 
412     s->vnet_hdr = false;
413     object_property_add_bool(obj, "vnet_hdr_support",
414                              filter_redirector_get_vnet_hdr,
415                              filter_redirector_set_vnet_hdr);
416 }
417 
418 static void filter_mirror_fini(Object *obj)
419 {
420     MirrorState *s = FILTER_MIRROR(obj);
421 
422     g_free(s->outdev);
423 }
424 
425 static void filter_redirector_fini(Object *obj)
426 {
427     MirrorState *s = FILTER_REDIRECTOR(obj);
428 
429     g_free(s->indev);
430     g_free(s->outdev);
431 }
432 
433 static const TypeInfo filter_redirector_info = {
434     .name = TYPE_FILTER_REDIRECTOR,
435     .parent = TYPE_NETFILTER,
436     .class_init = filter_redirector_class_init,
437     .instance_init = filter_redirector_init,
438     .instance_finalize = filter_redirector_fini,
439     .instance_size = sizeof(MirrorState),
440 };
441 
442 static const TypeInfo filter_mirror_info = {
443     .name = TYPE_FILTER_MIRROR,
444     .parent = TYPE_NETFILTER,
445     .class_init = filter_mirror_class_init,
446     .instance_init = filter_mirror_init,
447     .instance_finalize = filter_mirror_fini,
448     .instance_size = sizeof(MirrorState),
449 };
450 
451 static void register_types(void)
452 {
453     type_register_static(&filter_mirror_info);
454     type_register_static(&filter_redirector_info);
455 }
456 
457 type_init(register_types);
458