xref: /openbmc/qemu/net/dump.c (revision 8f951a13f0dd801dcf95c822091a7db49b323ca2)
1  /*
2   * QEMU System Emulator
3   *
4   * Copyright (c) 2003-2008 Fabrice Bellard
5   *
6   * Permission is hereby granted, free of charge, to any person obtaining a copy
7   * of this software and associated documentation files (the "Software"), to deal
8   * in the Software without restriction, including without limitation the rights
9   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10   * copies of the Software, and to permit persons to whom the Software is
11   * furnished to do so, subject to the following conditions:
12   *
13   * The above copyright notice and this permission notice shall be included in
14   * all copies or substantial portions of the Software.
15   *
16   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19   * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22   * THE SOFTWARE.
23   */
24  
25  #include "qemu/osdep.h"
26  #include "clients.h"
27  #include "qapi/error.h"
28  #include "qemu-common.h"
29  #include "qemu/error-report.h"
30  #include "qemu/iov.h"
31  #include "qemu/log.h"
32  #include "qemu/timer.h"
33  #include "qapi/visitor.h"
34  #include "net/filter.h"
35  
36  typedef struct DumpState {
37      int64_t start_ts;
38      int fd;
39      int pcap_caplen;
40  } DumpState;
41  
42  #define PCAP_MAGIC 0xa1b2c3d4
43  
44  struct pcap_file_hdr {
45      uint32_t magic;
46      uint16_t version_major;
47      uint16_t version_minor;
48      int32_t thiszone;
49      uint32_t sigfigs;
50      uint32_t snaplen;
51      uint32_t linktype;
52  };
53  
54  struct pcap_sf_pkthdr {
55      struct {
56          int32_t tv_sec;
57          int32_t tv_usec;
58      } ts;
59      uint32_t caplen;
60      uint32_t len;
61  };
62  
63  static ssize_t dump_receive_iov(DumpState *s, const struct iovec *iov, int cnt)
64  {
65      struct pcap_sf_pkthdr hdr;
66      int64_t ts;
67      int caplen;
68      size_t size = iov_size(iov, cnt);
69      struct iovec dumpiov[cnt + 1];
70  
71      /* Early return in case of previous error. */
72      if (s->fd < 0) {
73          return size;
74      }
75  
76      ts = qemu_clock_get_us(QEMU_CLOCK_VIRTUAL);
77      caplen = size > s->pcap_caplen ? s->pcap_caplen : size;
78  
79      hdr.ts.tv_sec = ts / 1000000 + s->start_ts;
80      hdr.ts.tv_usec = ts % 1000000;
81      hdr.caplen = caplen;
82      hdr.len = size;
83  
84      dumpiov[0].iov_base = &hdr;
85      dumpiov[0].iov_len = sizeof(hdr);
86      cnt = iov_copy(&dumpiov[1], cnt, iov, cnt, 0, caplen);
87  
88      if (writev(s->fd, dumpiov, cnt + 1) != sizeof(hdr) + caplen) {
89          error_report("network dump write error - stopping dump");
90          close(s->fd);
91          s->fd = -1;
92      }
93  
94      return size;
95  }
96  
97  static void dump_cleanup(DumpState *s)
98  {
99      close(s->fd);
100      s->fd = -1;
101  }
102  
103  static int net_dump_state_init(DumpState *s, const char *filename,
104                                 int len, Error **errp)
105  {
106      struct pcap_file_hdr hdr;
107      struct tm tm;
108      int fd;
109  
110      fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY | O_BINARY, 0644);
111      if (fd < 0) {
112          error_setg_errno(errp, errno, "net dump: can't open %s", filename);
113          return -1;
114      }
115  
116      hdr.magic = PCAP_MAGIC;
117      hdr.version_major = 2;
118      hdr.version_minor = 4;
119      hdr.thiszone = 0;
120      hdr.sigfigs = 0;
121      hdr.snaplen = len;
122      hdr.linktype = 1;
123  
124      if (write(fd, &hdr, sizeof(hdr)) < sizeof(hdr)) {
125          error_setg_errno(errp, errno, "net dump write error");
126          close(fd);
127          return -1;
128      }
129  
130      s->fd = fd;
131      s->pcap_caplen = len;
132  
133      qemu_get_timedate(&tm, 0);
134      s->start_ts = mktime(&tm);
135  
136      return 0;
137  }
138  
139  #define TYPE_FILTER_DUMP "filter-dump"
140  
141  #define FILTER_DUMP(obj) \
142      OBJECT_CHECK(NetFilterDumpState, (obj), TYPE_FILTER_DUMP)
143  
144  struct NetFilterDumpState {
145      NetFilterState nfs;
146      DumpState ds;
147      char *filename;
148      uint32_t maxlen;
149  };
150  typedef struct NetFilterDumpState NetFilterDumpState;
151  
152  static ssize_t filter_dump_receive_iov(NetFilterState *nf, NetClientState *sndr,
153                                         unsigned flags, const struct iovec *iov,
154                                         int iovcnt, NetPacketSent *sent_cb)
155  {
156      NetFilterDumpState *nfds = FILTER_DUMP(nf);
157  
158      dump_receive_iov(&nfds->ds, iov, iovcnt);
159      return 0;
160  }
161  
162  static void filter_dump_cleanup(NetFilterState *nf)
163  {
164      NetFilterDumpState *nfds = FILTER_DUMP(nf);
165  
166      dump_cleanup(&nfds->ds);
167  }
168  
169  static void filter_dump_setup(NetFilterState *nf, Error **errp)
170  {
171      NetFilterDumpState *nfds = FILTER_DUMP(nf);
172  
173      if (!nfds->filename) {
174          error_setg(errp, "dump filter needs 'file' property set!");
175          return;
176      }
177  
178      net_dump_state_init(&nfds->ds, nfds->filename, nfds->maxlen, errp);
179  }
180  
181  static void filter_dump_get_maxlen(Object *obj, Visitor *v, const char *name,
182                                     void *opaque, Error **errp)
183  {
184      NetFilterDumpState *nfds = FILTER_DUMP(obj);
185      uint32_t value = nfds->maxlen;
186  
187      visit_type_uint32(v, name, &value, errp);
188  }
189  
190  static void filter_dump_set_maxlen(Object *obj, Visitor *v, const char *name,
191                                     void *opaque, Error **errp)
192  {
193      NetFilterDumpState *nfds = FILTER_DUMP(obj);
194      Error *local_err = NULL;
195      uint32_t value;
196  
197      visit_type_uint32(v, name, &value, &local_err);
198      if (local_err) {
199          goto out;
200      }
201      if (value == 0) {
202          error_setg(&local_err, "Property '%s.%s' doesn't take value '%u'",
203                     object_get_typename(obj), name, value);
204          goto out;
205      }
206      nfds->maxlen = value;
207  
208  out:
209      error_propagate(errp, local_err);
210  }
211  
212  static char *file_dump_get_filename(Object *obj, Error **errp)
213  {
214      NetFilterDumpState *nfds = FILTER_DUMP(obj);
215  
216      return g_strdup(nfds->filename);
217  }
218  
219  static void file_dump_set_filename(Object *obj, const char *value, Error **errp)
220  {
221     NetFilterDumpState *nfds = FILTER_DUMP(obj);
222  
223      g_free(nfds->filename);
224      nfds->filename = g_strdup(value);
225  }
226  
227  static void filter_dump_instance_init(Object *obj)
228  {
229      NetFilterDumpState *nfds = FILTER_DUMP(obj);
230  
231      nfds->maxlen = 65536;
232  
233      object_property_add(obj, "maxlen", "uint32", filter_dump_get_maxlen,
234                          filter_dump_set_maxlen, NULL, NULL, NULL);
235      object_property_add_str(obj, "file", file_dump_get_filename,
236                              file_dump_set_filename, NULL);
237  }
238  
239  static void filter_dump_instance_finalize(Object *obj)
240  {
241      NetFilterDumpState *nfds = FILTER_DUMP(obj);
242  
243      g_free(nfds->filename);
244  }
245  
246  static void filter_dump_class_init(ObjectClass *oc, void *data)
247  {
248      NetFilterClass *nfc = NETFILTER_CLASS(oc);
249  
250      nfc->setup = filter_dump_setup;
251      nfc->cleanup = filter_dump_cleanup;
252      nfc->receive_iov = filter_dump_receive_iov;
253  }
254  
255  static const TypeInfo filter_dump_info = {
256      .name = TYPE_FILTER_DUMP,
257      .parent = TYPE_NETFILTER,
258      .class_init = filter_dump_class_init,
259      .instance_init = filter_dump_instance_init,
260      .instance_finalize = filter_dump_instance_finalize,
261      .instance_size = sizeof(NetFilterDumpState),
262  };
263  
264  static void filter_dump_register_types(void)
265  {
266      type_register_static(&filter_dump_info);
267  }
268  
269  type_init(filter_dump_register_types);
270