summaryrefslogtreecommitdiff
path: root/net/dump.c
blob: 0d0cbb2591ef31bc36ddecb00ba2cbc57bd6da96 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
/*
 * QEMU System Emulator
 *
 * Copyright (c) 2003-2008 Fabrice Bellard
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "dump.h"
#include "qemu-common.h"
#include "qemu-error.h"
#include "qemu-log.h"
#include "qemu-timer.h"

typedef struct DumpState {
    VLANClientState nc;
    int fd;
    int pcap_caplen;
} DumpState;

#define PCAP_MAGIC 0xa1b2c3d4

struct pcap_file_hdr {
    uint32_t magic;
    uint16_t version_major;
    uint16_t version_minor;
    int32_t thiszone;
    uint32_t sigfigs;
    uint32_t snaplen;
    uint32_t linktype;
};

struct pcap_sf_pkthdr {
    struct {
        int32_t tv_sec;
        int32_t tv_usec;
    } ts;
    uint32_t caplen;
    uint32_t len;
};

static ssize_t dump_receive(VLANClientState *nc, const uint8_t *buf, size_t size)
{
    DumpState *s = DO_UPCAST(DumpState, nc, nc);
    struct pcap_sf_pkthdr hdr;
    int64_t ts;
    int caplen;

    /* Early return in case of previous error. */
    if (s->fd < 0) {
        return size;
    }

    ts = muldiv64(qemu_get_clock_ns(vm_clock), 1000000, get_ticks_per_sec());
    caplen = size > s->pcap_caplen ? s->pcap_caplen : size;

    hdr.ts.tv_sec = ts / 1000000;
    hdr.ts.tv_usec = ts % 1000000;
    hdr.caplen = caplen;
    hdr.len = size;
    if (write(s->fd, &hdr, sizeof(hdr)) != sizeof(hdr) ||
        write(s->fd, buf, caplen) != caplen) {
        qemu_log("-net dump write error - stop dump\n");
        close(s->fd);
        s->fd = -1;
    }

    return size;
}

static void dump_cleanup(VLANClientState *nc)
{
    DumpState *s = DO_UPCAST(DumpState, nc, nc);

    close(s->fd);
}

static NetClientInfo net_dump_info = {
    .type = NET_CLIENT_TYPE_DUMP,
    .size = sizeof(DumpState),
    .receive = dump_receive,
    .cleanup = dump_cleanup,
};

static int net_dump_init(VLANState *vlan, const char *device,
                         const char *name, const char *filename, int len)
{
    struct pcap_file_hdr hdr;
    VLANClientState *nc;
    DumpState *s;
    int fd;

    fd = open(filename, O_CREAT | O_WRONLY | O_BINARY, 0644);
    if (fd < 0) {
        error_report("-net dump: can't open %s", filename);
        return -1;
    }

    hdr.magic = PCAP_MAGIC;
    hdr.version_major = 2;
    hdr.version_minor = 4;
    hdr.thiszone = 0;
    hdr.sigfigs = 0;
    hdr.snaplen = len;
    hdr.linktype = 1;

    if (write(fd, &hdr, sizeof(hdr)) < sizeof(hdr)) {
        error_report("-net dump write error: %s", strerror(errno));
        close(fd);
        return -1;
    }

    nc = qemu_new_net_client(&net_dump_info, vlan, NULL, device, name);

    snprintf(nc->info_str, sizeof(nc->info_str),
             "dump to %s (len=%d)", filename, len);

    s = DO_UPCAST(DumpState, nc, nc);

    s->fd = fd;
    s->pcap_caplen = len;

    return 0;
}

int net_init_dump(QemuOpts *opts, Monitor *mon, const char *name, VLANState *vlan)
{
    int len;
    const char *file;
    char def_file[128];

    assert(vlan);

    file = qemu_opt_get(opts, "file");
    if (!file) {
        snprintf(def_file, sizeof(def_file), "qemu-vlan%d.pcap", vlan->id);
        file = def_file;
    }

    len = qemu_opt_get_size(opts, "len", 65536);

    return net_dump_init(vlan, "dump", name, file, len);
}