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 #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 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);
 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);