xref: /openbmc/qemu/net/filter-mirror.c (revision c39860e6dc90f6ee2e82ee078f978c5d7f3df86a)
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/qmp/qerror.h"
18 #include "qapi-visit.h"
19 #include "qom/object.h"
20 #include "qemu/main-loop.h"
21 #include "qemu/error-report.h"
22 #include "trace.h"
23 #include "sysemu/char.h"
24 #include "qemu/iov.h"
25 #include "qemu/sockets.h"
26 
27 #define FILTER_MIRROR(obj) \
28     OBJECT_CHECK(MirrorState, (obj), TYPE_FILTER_MIRROR)
29 
30 #define FILTER_REDIRECTOR(obj) \
31     OBJECT_CHECK(MirrorState, (obj), TYPE_FILTER_REDIRECTOR)
32 
33 #define TYPE_FILTER_MIRROR "filter-mirror"
34 #define TYPE_FILTER_REDIRECTOR "filter-redirector"
35 #define REDIRECTOR_MAX_LEN NET_BUFSIZE
36 
37 typedef struct MirrorState {
38     NetFilterState parent_obj;
39     char *indev;
40     char *outdev;
41     CharBackend chr_in;
42     CharBackend chr_out;
43     SocketReadState rs;
44 } MirrorState;
45 
46 static int filter_mirror_send(CharBackend *chr_out,
47                               const struct iovec *iov,
48                               int iovcnt)
49 {
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(chr_out, (uint8_t *)&len, sizeof(len));
62     if (ret != sizeof(len)) {
63         goto err;
64     }
65 
66     buf = g_malloc(size);
67     iov_to_buf(iov, iovcnt, 0, buf, size);
68     ret = qemu_chr_fe_write_all(chr_out, (uint8_t *)buf, size);
69     g_free(buf);
70     if (ret != size) {
71         goto err;
72     }
73 
74     return 0;
75 
76 err:
77     return ret < 0 ? ret : -EIO;
78 }
79 
80 static void
81 redirector_to_filter(NetFilterState *nf, const uint8_t *buf, int len)
82 {
83     struct iovec iov = {
84         .iov_base = (void *)buf,
85         .iov_len = len,
86     };
87 
88     if (nf->direction == NET_FILTER_DIRECTION_ALL ||
89         nf->direction == NET_FILTER_DIRECTION_TX) {
90         qemu_netfilter_pass_to_next(nf->netdev, 0, &iov, 1, nf);
91     }
92 
93     if (nf->direction == NET_FILTER_DIRECTION_ALL ||
94         nf->direction == NET_FILTER_DIRECTION_RX) {
95         qemu_netfilter_pass_to_next(nf->netdev->peer, 0, &iov, 1, nf);
96      }
97 }
98 
99 static int redirector_chr_can_read(void *opaque)
100 {
101     return REDIRECTOR_MAX_LEN;
102 }
103 
104 static void redirector_chr_read(void *opaque, const uint8_t *buf, int size)
105 {
106     NetFilterState *nf = opaque;
107     MirrorState *s = FILTER_REDIRECTOR(nf);
108     int ret;
109 
110     ret = net_fill_rstate(&s->rs, buf, size);
111 
112     if (ret == -1) {
113         qemu_chr_fe_set_handlers(&s->chr_in, NULL, NULL, NULL, NULL, NULL);
114     }
115 }
116 
117 static void redirector_chr_event(void *opaque, int event)
118 {
119     NetFilterState *nf = opaque;
120     MirrorState *s = FILTER_REDIRECTOR(nf);
121 
122     switch (event) {
123     case CHR_EVENT_CLOSED:
124         qemu_chr_fe_set_handlers(&s->chr_in, NULL, NULL, NULL, NULL, NULL);
125         break;
126     default:
127         break;
128     }
129 }
130 
131 static ssize_t filter_mirror_receive_iov(NetFilterState *nf,
132                                          NetClientState *sender,
133                                          unsigned flags,
134                                          const struct iovec *iov,
135                                          int iovcnt,
136                                          NetPacketSent *sent_cb)
137 {
138     MirrorState *s = FILTER_MIRROR(nf);
139     int ret;
140 
141     ret = filter_mirror_send(&s->chr_out, iov, iovcnt);
142     if (ret) {
143         error_report("filter_mirror_send failed(%s)", strerror(-ret));
144     }
145 
146     /*
147      * we don't hope this error interrupt the normal
148      * path of net packet, so we always return zero.
149      */
150     return 0;
151 }
152 
153 static ssize_t filter_redirector_receive_iov(NetFilterState *nf,
154                                              NetClientState *sender,
155                                              unsigned flags,
156                                              const struct iovec *iov,
157                                              int iovcnt,
158                                              NetPacketSent *sent_cb)
159 {
160     MirrorState *s = FILTER_REDIRECTOR(nf);
161     int ret;
162 
163     if (qemu_chr_fe_get_driver(&s->chr_out)) {
164         ret = filter_mirror_send(&s->chr_out, iov, iovcnt);
165         if (ret) {
166             error_report("filter_mirror_send failed(%s)", strerror(-ret));
167         }
168         return iov_size(iov, iovcnt);
169     } else {
170         return 0;
171     }
172 }
173 
174 static void filter_mirror_cleanup(NetFilterState *nf)
175 {
176     MirrorState *s = FILTER_MIRROR(nf);
177 
178     qemu_chr_fe_deinit(&s->chr_out);
179 }
180 
181 static void filter_redirector_cleanup(NetFilterState *nf)
182 {
183     MirrorState *s = FILTER_REDIRECTOR(nf);
184 
185     qemu_chr_fe_deinit(&s->chr_in);
186     qemu_chr_fe_deinit(&s->chr_out);
187 }
188 
189 static void filter_mirror_setup(NetFilterState *nf, Error **errp)
190 {
191     MirrorState *s = FILTER_MIRROR(nf);
192     CharDriverState *chr;
193 
194     if (!s->outdev) {
195         error_setg(errp, "filter mirror needs 'outdev' "
196                    "property set");
197         return;
198     }
199 
200     chr = qemu_chr_find(s->outdev);
201     if (chr == NULL) {
202         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
203                   "Device '%s' not found", s->outdev);
204         return;
205     }
206 
207     qemu_chr_fe_init(&s->chr_out, chr, errp);
208 }
209 
210 static void redirector_rs_finalize(SocketReadState *rs)
211 {
212     MirrorState *s = container_of(rs, MirrorState, rs);
213     NetFilterState *nf = NETFILTER(s);
214 
215     redirector_to_filter(nf, rs->buf, rs->packet_len);
216 }
217 
218 static void filter_redirector_setup(NetFilterState *nf, Error **errp)
219 {
220     MirrorState *s = FILTER_REDIRECTOR(nf);
221     CharDriverState *chr;
222 
223     if (!s->indev && !s->outdev) {
224         error_setg(errp, "filter redirector needs 'indev' or "
225                    "'outdev' at least one property set");
226         return;
227     } else if (s->indev && s->outdev) {
228         if (!strcmp(s->indev, s->outdev)) {
229             error_setg(errp, "'indev' and 'outdev' could not be same "
230                        "for filter redirector");
231             return;
232         }
233     }
234 
235     net_socket_rs_init(&s->rs, redirector_rs_finalize);
236 
237     if (s->indev) {
238         chr = qemu_chr_find(s->indev);
239         if (chr == NULL) {
240             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
241                       "IN Device '%s' not found", s->indev);
242             return;
243         }
244 
245         if (!qemu_chr_fe_init(&s->chr_in, chr, errp)) {
246             return;
247         }
248 
249         qemu_chr_fe_set_handlers(&s->chr_in, redirector_chr_can_read,
250                                  redirector_chr_read, redirector_chr_event,
251                                  nf, NULL);
252     }
253 
254     if (s->outdev) {
255         chr = qemu_chr_find(s->outdev);
256         if (chr == NULL) {
257             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
258                       "OUT Device '%s' not found", s->outdev);
259             return;
260         }
261         if (!qemu_chr_fe_init(&s->chr_out, chr, errp)) {
262             return;
263         }
264     }
265 }
266 
267 static void filter_mirror_class_init(ObjectClass *oc, void *data)
268 {
269     NetFilterClass *nfc = NETFILTER_CLASS(oc);
270 
271     nfc->setup = filter_mirror_setup;
272     nfc->cleanup = filter_mirror_cleanup;
273     nfc->receive_iov = filter_mirror_receive_iov;
274 }
275 
276 static void filter_redirector_class_init(ObjectClass *oc, void *data)
277 {
278     NetFilterClass *nfc = NETFILTER_CLASS(oc);
279 
280     nfc->setup = filter_redirector_setup;
281     nfc->cleanup = filter_redirector_cleanup;
282     nfc->receive_iov = filter_redirector_receive_iov;
283 }
284 
285 static char *filter_redirector_get_indev(Object *obj, Error **errp)
286 {
287     MirrorState *s = FILTER_REDIRECTOR(obj);
288 
289     return g_strdup(s->indev);
290 }
291 
292 static void
293 filter_redirector_set_indev(Object *obj, const char *value, Error **errp)
294 {
295     MirrorState *s = FILTER_REDIRECTOR(obj);
296 
297     g_free(s->indev);
298     s->indev = g_strdup(value);
299 }
300 
301 static char *filter_mirror_get_outdev(Object *obj, Error **errp)
302 {
303     MirrorState *s = FILTER_MIRROR(obj);
304 
305     return g_strdup(s->outdev);
306 }
307 
308 static void
309 filter_mirror_set_outdev(Object *obj, const char *value, Error **errp)
310 {
311     MirrorState *s = FILTER_MIRROR(obj);
312 
313     g_free(s->outdev);
314     s->outdev = g_strdup(value);
315     if (!s->outdev) {
316         error_setg(errp, "filter mirror needs 'outdev' "
317                    "property set");
318         return;
319     }
320 }
321 
322 static char *filter_redirector_get_outdev(Object *obj, Error **errp)
323 {
324     MirrorState *s = FILTER_REDIRECTOR(obj);
325 
326     return g_strdup(s->outdev);
327 }
328 
329 static void
330 filter_redirector_set_outdev(Object *obj, const char *value, Error **errp)
331 {
332     MirrorState *s = FILTER_REDIRECTOR(obj);
333 
334     g_free(s->outdev);
335     s->outdev = g_strdup(value);
336 }
337 
338 static void filter_mirror_init(Object *obj)
339 {
340     object_property_add_str(obj, "outdev", filter_mirror_get_outdev,
341                             filter_mirror_set_outdev, NULL);
342 }
343 
344 static void filter_redirector_init(Object *obj)
345 {
346     object_property_add_str(obj, "indev", filter_redirector_get_indev,
347                             filter_redirector_set_indev, NULL);
348     object_property_add_str(obj, "outdev", filter_redirector_get_outdev,
349                             filter_redirector_set_outdev, NULL);
350 }
351 
352 static void filter_mirror_fini(Object *obj)
353 {
354     MirrorState *s = FILTER_MIRROR(obj);
355 
356     g_free(s->outdev);
357 }
358 
359 static void filter_redirector_fini(Object *obj)
360 {
361     MirrorState *s = FILTER_REDIRECTOR(obj);
362 
363     g_free(s->indev);
364     g_free(s->outdev);
365 }
366 
367 static const TypeInfo filter_redirector_info = {
368     .name = TYPE_FILTER_REDIRECTOR,
369     .parent = TYPE_NETFILTER,
370     .class_init = filter_redirector_class_init,
371     .instance_init = filter_redirector_init,
372     .instance_finalize = filter_redirector_fini,
373     .instance_size = sizeof(MirrorState),
374 };
375 
376 static const TypeInfo filter_mirror_info = {
377     .name = TYPE_FILTER_MIRROR,
378     .parent = TYPE_NETFILTER,
379     .class_init = filter_mirror_class_init,
380     .instance_init = filter_mirror_init,
381     .instance_finalize = filter_mirror_fini,
382     .instance_size = sizeof(MirrorState),
383 };
384 
385 static void register_types(void)
386 {
387     type_register_static(&filter_mirror_info);
388     type_register_static(&filter_redirector_info);
389 }
390 
391 type_init(register_types);
392