net/dump.c

   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
  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 {
  66     struct pcap_sf_pkthdr hdr;
  67     int64_t ts;
  68     int caplen;
  69     size_t size = iov_size(iov, cnt);
  70     struct iovec dumpiov[cnt + 1];
  71
  72     /* Early return in case of previous error. */
  73     if (s->fd < 0) {
  74         return size;
  75     }
  76
  77     ts = qemu_clock_get_us(QEMU_CLOCK_VIRTUAL);
  78     caplen = size > s->pcap_caplen ? s->pcap_caplen : size;
  79
  80     hdr.ts.tv_sec = ts / 1000000 + s->start_ts;
  81     hdr.ts.tv_usec = ts % 1000000;
  82     hdr.caplen = caplen;
  83     hdr.len = size;
  84
  85     dumpiov[0].iov_base = &hdr;
  86     dumpiov[0].iov_len = sizeof(hdr);
  87     cnt = iov_copy(&dumpiov[1], cnt, iov, cnt, 0, caplen);
  88
  89     if (writev(s->fd, dumpiov, cnt + 1) != sizeof(hdr) + caplen) {
  90         error_report("network dump write error - stopping dump");
  91         close(s->fd);
  92         s->fd = -1;
  93     }
  94
  95     return size;
  96 }
  97
  98 static void dump_cleanup(DumpState *s)
  99 {
 100     close(s->fd);
 101     s->fd = -1;
 102 }
 103
 104 static int net_dump_state_init(DumpState *s, const char *filename,
 105                                int len, Error **errp)
 106 {
 107     struct pcap_file_hdr hdr;
 108     struct tm tm;
 109     int fd;
 110
 111     fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY | O_BINARY, 0644);
 112     if (fd < 0) {
 113         error_setg_errno(errp, errno, "net dump: can't open %s", filename);
 114         return -1;
 115     }
 116
 117     hdr.magic = PCAP_MAGIC;
 118     hdr.version_major = 2;
 119     hdr.version_minor = 4;
 120     hdr.thiszone = 0;
 121     hdr.sigfigs = 0;
 122     hdr.snaplen = len;
 123     hdr.linktype = 1;
 124
 125     if (write(fd, &hdr, sizeof(hdr)) < sizeof(hdr)) {
 126         error_setg_errno(errp, errno, "net dump write error");
 127         close(fd);
 128         return -1;
 129     }
 130
 131     s->fd = fd;
 132     s->pcap_caplen = len;
 133
 134     qemu_get_timedate(&tm, 0);
 135     s->start_ts = mktime(&tm);
 136
 137     return 0;
 138 }
 139
 140 #define TYPE_FILTER_DUMP "filter-dump"
 141
 142 #define FILTER_DUMP(obj) \
 143     OBJECT_CHECK(NetFilterDumpState, (obj), TYPE_FILTER_DUMP)
 144
 145 struct NetFilterDumpState {
 146     NetFilterState nfs;
 147     DumpState ds;
 148     char *filename;
 149     uint32_t maxlen;
 150 };
 151 typedef struct NetFilterDumpState NetFilterDumpState;
 152
 153 static ssize_t filter_dump_receive_iov(NetFilterState *nf, NetClientState *sndr,
 154                                        unsigned flags, const struct iovec *iov,
 155                                        int iovcnt, NetPacketSent *sent_cb)
 156 {
 157     NetFilterDumpState *nfds = FILTER_DUMP(nf);
 158
 159     dump_receive_iov(&nfds->ds, iov, iovcnt);
 160     return 0;
 161 }
 162
 163 static void filter_dump_cleanup(NetFilterState *nf)
 164 {
 165     NetFilterDumpState *nfds = FILTER_DUMP(nf);
 166
 167     dump_cleanup(&nfds->ds);
 168 }
 169
 170 static void filter_dump_setup(NetFilterState *nf, Error **errp)
 171 {
 172     NetFilterDumpState *nfds = FILTER_DUMP(nf);
 173
 174     if (!nfds->filename) {
 175         error_setg(errp, "dump filter needs 'file' property set!");
 176         return;
 177     }
 178
 179     net_dump_state_init(&nfds->ds, nfds->filename, nfds->maxlen, errp);
 180 }
 181
 182 static void filter_dump_get_maxlen(Object *obj, Visitor *v, const char *name,
 183                                    void *opaque, Error **errp)
 184 {
 185     NetFilterDumpState *nfds = FILTER_DUMP(obj);
 186     uint32_t value = nfds->maxlen;
 187
 188     visit_type_uint32(v, name, &value, errp);
 189 }
 190
 191 static void filter_dump_set_maxlen(Object *obj, Visitor *v, const char *name,
 192                                    void *opaque, Error **errp)
 193 {
 194     NetFilterDumpState *nfds = FILTER_DUMP(obj);
 195     Error *local_err = NULL;
 196     uint32_t value;
 197
 198     visit_type_uint32(v, name, &value, &local_err);
 199     if (local_err) {
 200         goto out;
 201     }
 202     if (value == 0) {
 203         error_setg(&local_err, "Property '%s.%s' doesn't take value '%u'",
 204                    object_get_typename(obj), name, value);
 205         goto out;
 206     }
 207     nfds->maxlen = value;
 208
 209 out:
 210     error_propagate(errp, local_err);
 211 }
 212
 213 static char *file_dump_get_filename(Object *obj, Error **errp)
 214 {
 215     NetFilterDumpState *nfds = FILTER_DUMP(obj);
 216
 217     return g_strdup(nfds->filename);
 218 }
 219
 220 static void file_dump_set_filename(Object *obj, const char *value, Error **errp)
 221 {
 222    NetFilterDumpState *nfds = FILTER_DUMP(obj);
 223
 224     g_free(nfds->filename);
 225     nfds->filename = g_strdup(value);
 226 }
 227
 228 static void filter_dump_instance_init(Object *obj)
 229 {
 230     NetFilterDumpState *nfds = FILTER_DUMP(obj);
 231
 232     nfds->maxlen = 65536;
 233
 234     object_property_add(obj, "maxlen", "uint32", filter_dump_get_maxlen,
 235                         filter_dump_set_maxlen, NULL, NULL, NULL);
 236     object_property_add_str(obj, "file", file_dump_get_filename,
 237                             file_dump_set_filename, NULL);
 238 }
 239
 240 static void filter_dump_instance_finalize(Object *obj)
 241 {
 242     NetFilterDumpState *nfds = FILTER_DUMP(obj);
 243
 244     g_free(nfds->filename);
 245 }
 246
 247 static void filter_dump_class_init(ObjectClass *oc, void *data)
 248 {
 249     NetFilterClass *nfc = NETFILTER_CLASS(oc);
 250
 251     nfc->setup = filter_dump_setup;
 252     nfc->cleanup = filter_dump_cleanup;
 253     nfc->receive_iov = filter_dump_receive_iov;
 254 }
 255
 256 static const TypeInfo filter_dump_info = {
 257     .name = TYPE_FILTER_DUMP,
 258     .parent = TYPE_NETFILTER,
 259     .class_init = filter_dump_class_init,
 260     .instance_init = filter_dump_instance_init,
 261     .instance_finalize = filter_dump_instance_finalize,
 262     .instance_size = sizeof(NetFilterDumpState),
 263 };
 264
 265 static void filter_dump_register_types(void)
 266 {
 267     type_register_static(&filter_dump_info);
 268 }
 269
 270 type_init(filter_dump_register_types);