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 "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);