xref: /openbmc/qemu/net/dump.c (revision 520e210c)
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