xref: /openbmc/qemu/net/dump.c (revision 7c08eefc) 
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/error-report.h"
29 #include "qemu/iov.h"
30 #include "qemu/module.h"
31 #include "qemu/timer.h"
32 #include "qapi/visitor.h"
33 #include "net/filter.h"
34 #include "qom/object.h"
35 #include "sysemu/rtc.h"
36 
37 typedef struct DumpState {
38     int64_t start_ts;
39     int fd;
40     int pcap_caplen;
41 } DumpState;
42 
43 #define PCAP_MAGIC 0xa1b2c3d4
44 
45 struct pcap_file_hdr {
46     uint32_t magic;
47     uint16_t version_major;
48     uint16_t version_minor;
49     int32_t thiszone;
50     uint32_t sigfigs;
51     uint32_t snaplen;
52     uint32_t linktype;
53 };
54 
55 struct pcap_sf_pkthdr {
56     struct {
57         int32_t tv_sec;
58         int32_t tv_usec;
59     } ts;
60     uint32_t caplen;
61     uint32_t len;
62 };
63 
64 static ssize_t dump_receive_iov(DumpState *s, const struct iovec *iov, int cnt,
65                                 int offset)
66 {
67     struct pcap_sf_pkthdr hdr;
68     int64_t ts;
69     int caplen;
70     size_t size = iov_size(iov, cnt) - offset;
71     g_autofree struct iovec *dumpiov = g_new(struct iovec, cnt + 1);
72 
73     /* Early return in case of previous error. */
74     if (s->fd < 0) {
75         return size;
76     }
77 
78     ts = qemu_clock_get_us(QEMU_CLOCK_VIRTUAL);
79     caplen = size > s->pcap_caplen ? s->pcap_caplen : size;
80 
81     hdr.ts.tv_sec = ts / 1000000 + s->start_ts;
82     hdr.ts.tv_usec = ts % 1000000;
83     hdr.caplen = caplen;
84     hdr.len = size;
85 
86     dumpiov[0].iov_base = &hdr;
87     dumpiov[0].iov_len = sizeof(hdr);
88     cnt = iov_copy(&dumpiov[1], cnt, iov, cnt, offset, caplen);
89 
90     if (writev(s->fd, dumpiov, cnt + 1) != sizeof(hdr) + caplen) {
91         error_report("network dump write error - stopping dump");
92         close(s->fd);
93         s->fd = -1;
94     }
95 
96     return size;
97 }
98 
99 static void dump_cleanup(DumpState *s)
100 {
101     close(s->fd);
102     s->fd = -1;
103 }
104 
105 static int net_dump_state_init(DumpState *s, const char *filename,
106                                int len, Error **errp)
107 {
108     struct pcap_file_hdr hdr;
109     struct tm tm;
110     int fd;
111 
112     fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY | O_BINARY, 0644);
113     if (fd < 0) {
114         error_setg_errno(errp, errno, "net dump: can't open %s", filename);
115         return -1;
116     }
117 
118     hdr.magic = PCAP_MAGIC;
119     hdr.version_major = 2;
120     hdr.version_minor = 4;
121     hdr.thiszone = 0;
122     hdr.sigfigs = 0;
123     hdr.snaplen = len;
124     hdr.linktype = 1;
125 
126     if (write(fd, &hdr, sizeof(hdr)) < sizeof(hdr)) {
127         error_setg_errno(errp, errno, "net dump write error");
128         close(fd);
129         return -1;
130     }
131 
132     s->fd = fd;
133     s->pcap_caplen = len;
134 
135     qemu_get_timedate(&tm, 0);
136     s->start_ts = mktime(&tm);
137 
138     return 0;
139 }
140 
141 #define TYPE_FILTER_DUMP "filter-dump"
142 
143 OBJECT_DECLARE_SIMPLE_TYPE(NetFilterDumpState, FILTER_DUMP)
144 
145 struct NetFilterDumpState {
146     NetFilterState nfs;
147     DumpState ds;
148     char *filename;
149     uint32_t maxlen;
150 };
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, qemu_get_vnet_hdr_len(nf->netdev));
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     uint32_t value;
195 
196     if (!visit_type_uint32(v, name, &value, errp)) {
197         return;
198     }
199     if (value == 0) {
200         error_setg(errp, "Property '%s.%s' doesn't take value '%u'",
201                    object_get_typename(obj), name, value);
202         return;
203     }
204     nfds->maxlen = value;
205 }
206 
207 static char *file_dump_get_filename(Object *obj, Error **errp)
208 {
209     NetFilterDumpState *nfds = FILTER_DUMP(obj);
210 
211     return g_strdup(nfds->filename);
212 }
213 
214 static void file_dump_set_filename(Object *obj, const char *value, Error **errp)
215 {
216    NetFilterDumpState *nfds = FILTER_DUMP(obj);
217 
218     g_free(nfds->filename);
219     nfds->filename = g_strdup(value);
220 }
221 
222 static void filter_dump_instance_init(Object *obj)
223 {
224     NetFilterDumpState *nfds = FILTER_DUMP(obj);
225 
226     nfds->maxlen = 65536;
227 }
228 
229 static void filter_dump_instance_finalize(Object *obj)
230 {
231     NetFilterDumpState *nfds = FILTER_DUMP(obj);
232 
233     g_free(nfds->filename);
234 }
235 
236 static void filter_dump_class_init(ObjectClass *oc, void *data)
237 {
238     NetFilterClass *nfc = NETFILTER_CLASS(oc);
239 
240     object_class_property_add(oc, "maxlen", "uint32", filter_dump_get_maxlen,
241                               filter_dump_set_maxlen, NULL, NULL);
242     object_class_property_add_str(oc, "file", file_dump_get_filename,
243                                   file_dump_set_filename);
244 
245     nfc->setup = filter_dump_setup;
246     nfc->cleanup = filter_dump_cleanup;
247     nfc->receive_iov = filter_dump_receive_iov;
248 }
249 
250 static const TypeInfo filter_dump_info = {
251     .name = TYPE_FILTER_DUMP,
252     .parent = TYPE_NETFILTER,
253     .class_init = filter_dump_class_init,
254     .instance_init = filter_dump_instance_init,
255     .instance_finalize = filter_dump_instance_finalize,
256     .instance_size = sizeof(NetFilterDumpState),
257 };
258 
259 static void filter_dump_register_types(void)
260 {
261     type_register_static(&filter_dump_info);
262 }
263 
264 type_init(filter_dump_register_types);
265