xref: /openbmc/qemu/net/dump.c (revision a68694cd)
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 "qemu-common.h"
27 #include "clients.h"
28 #include "qapi/error.h"
29 #include "qemu/error-report.h"
30 #include "qemu/iov.h"
31 #include "qemu/log.h"
32 #include "qemu/module.h"
33 #include "qemu/timer.h"
34 #include "qapi/visitor.h"
35 #include "net/filter.h"
36 #include "qom/object.h"
37 
38 typedef struct DumpState {
39     int64_t start_ts;
40     int fd;
41     int pcap_caplen;
42 } DumpState;
43 
44 #define PCAP_MAGIC 0xa1b2c3d4
45 
46 struct pcap_file_hdr {
47     uint32_t magic;
48     uint16_t version_major;
49     uint16_t version_minor;
50     int32_t thiszone;
51     uint32_t sigfigs;
52     uint32_t snaplen;
53     uint32_t linktype;
54 };
55 
56 struct pcap_sf_pkthdr {
57     struct {
58         int32_t tv_sec;
59         int32_t tv_usec;
60     } ts;
61     uint32_t caplen;
62     uint32_t len;
63 };
64 
65 static ssize_t dump_receive_iov(DumpState *s, const struct iovec *iov, int cnt)
66 {
67     struct pcap_sf_pkthdr hdr;
68     int64_t ts;
69     int caplen;
70     size_t size = iov_size(iov, cnt);
71     struct iovec dumpiov[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, 0, 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 typedef struct NetFilterDumpState NetFilterDumpState;
144 DECLARE_INSTANCE_CHECKER(NetFilterDumpState, FILTER_DUMP,
145                          TYPE_FILTER_DUMP)
146 
147 struct NetFilterDumpState {
148     NetFilterState nfs;
149     DumpState ds;
150     char *filename;
151     uint32_t maxlen;
152 };
153 
154 static ssize_t filter_dump_receive_iov(NetFilterState *nf, NetClientState *sndr,
155                                        unsigned flags, const struct iovec *iov,
156                                        int iovcnt, NetPacketSent *sent_cb)
157 {
158     NetFilterDumpState *nfds = FILTER_DUMP(nf);
159 
160     dump_receive_iov(&nfds->ds, iov, iovcnt);
161     return 0;
162 }
163 
164 static void filter_dump_cleanup(NetFilterState *nf)
165 {
166     NetFilterDumpState *nfds = FILTER_DUMP(nf);
167 
168     dump_cleanup(&nfds->ds);
169 }
170 
171 static void filter_dump_setup(NetFilterState *nf, Error **errp)
172 {
173     NetFilterDumpState *nfds = FILTER_DUMP(nf);
174 
175     if (!nfds->filename) {
176         error_setg(errp, "dump filter needs 'file' property set!");
177         return;
178     }
179 
180     net_dump_state_init(&nfds->ds, nfds->filename, nfds->maxlen, errp);
181 }
182 
183 static void filter_dump_get_maxlen(Object *obj, Visitor *v, const char *name,
184                                    void *opaque, Error **errp)
185 {
186     NetFilterDumpState *nfds = FILTER_DUMP(obj);
187     uint32_t value = nfds->maxlen;
188 
189     visit_type_uint32(v, name, &value, errp);
190 }
191 
192 static void filter_dump_set_maxlen(Object *obj, Visitor *v, const char *name,
193                                    void *opaque, Error **errp)
194 {
195     NetFilterDumpState *nfds = FILTER_DUMP(obj);
196     uint32_t value;
197 
198     if (!visit_type_uint32(v, name, &value, errp)) {
199         return;
200     }
201     if (value == 0) {
202         error_setg(errp, "Property '%s.%s' doesn't take value '%u'",
203                    object_get_typename(obj), name, value);
204         return;
205     }
206     nfds->maxlen = value;
207 }
208 
209 static char *file_dump_get_filename(Object *obj, Error **errp)
210 {
211     NetFilterDumpState *nfds = FILTER_DUMP(obj);
212 
213     return g_strdup(nfds->filename);
214 }
215 
216 static void file_dump_set_filename(Object *obj, const char *value, Error **errp)
217 {
218    NetFilterDumpState *nfds = FILTER_DUMP(obj);
219 
220     g_free(nfds->filename);
221     nfds->filename = g_strdup(value);
222 }
223 
224 static void filter_dump_instance_init(Object *obj)
225 {
226     NetFilterDumpState *nfds = FILTER_DUMP(obj);
227 
228     nfds->maxlen = 65536;
229 
230     object_property_add(obj, "maxlen", "uint32", filter_dump_get_maxlen,
231                         filter_dump_set_maxlen, NULL, NULL);
232     object_property_add_str(obj, "file", file_dump_get_filename,
233                             file_dump_set_filename);
234 }
235 
236 static void filter_dump_instance_finalize(Object *obj)
237 {
238     NetFilterDumpState *nfds = FILTER_DUMP(obj);
239 
240     g_free(nfds->filename);
241 }
242 
243 static void filter_dump_class_init(ObjectClass *oc, void *data)
244 {
245     NetFilterClass *nfc = NETFILTER_CLASS(oc);
246 
247     nfc->setup = filter_dump_setup;
248     nfc->cleanup = filter_dump_cleanup;
249     nfc->receive_iov = filter_dump_receive_iov;
250 }
251 
252 static const TypeInfo filter_dump_info = {
253     .name = TYPE_FILTER_DUMP,
254     .parent = TYPE_NETFILTER,
255     .class_init = filter_dump_class_init,
256     .instance_init = filter_dump_instance_init,
257     .instance_finalize = filter_dump_instance_finalize,
258     .instance_size = sizeof(NetFilterDumpState),
259 };
260 
261 static void filter_dump_register_types(void)
262 {
263     type_register_static(&filter_dump_info);
264 }
265 
266 type_init(filter_dump_register_types);
267