xref: /illumos-kvm-cmd/net/dump.c (revision 68396ea9)
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 "dump.h"
26 #include "qemu-common.h"
27 #include "sysemu.h"
28 #include "qemu-error.h"
29 #include "qemu-log.h"
30 
31 typedef struct DumpState {
32     VLANClientState nc;
33     int fd;
34     int pcap_caplen;
35 } DumpState;
36 
37 #define PCAP_MAGIC 0xa1b2c3d4
38 
39 struct pcap_file_hdr {
40     uint32_t magic;
41     uint16_t version_major;
42     uint16_t version_minor;
43     int32_t thiszone;
44     uint32_t sigfigs;
45     uint32_t snaplen;
46     uint32_t linktype;
47 };
48 
49 struct pcap_sf_pkthdr {
50     struct {
51         int32_t tv_sec;
52         int32_t tv_usec;
53     } ts;
54     uint32_t caplen;
55     uint32_t len;
56 };
57 
dump_receive(VLANClientState * nc,const uint8_t * buf,size_t size)58 static ssize_t dump_receive(VLANClientState *nc, const uint8_t *buf, size_t size)
59 {
60     DumpState *s = DO_UPCAST(DumpState, nc, nc);
61     struct pcap_sf_pkthdr hdr;
62     int64_t ts;
63     int caplen;
64 
65     /* Early return in case of previous error. */
66     if (s->fd < 0) {
67         return size;
68     }
69 
70     ts = muldiv64(qemu_get_clock(vm_clock), 1000000, get_ticks_per_sec());
71     caplen = size > s->pcap_caplen ? s->pcap_caplen : size;
72 
73     hdr.ts.tv_sec = ts / 1000000;
74     hdr.ts.tv_usec = ts % 1000000;
75     hdr.caplen = caplen;
76     hdr.len = size;
77     if (write(s->fd, &hdr, sizeof(hdr)) != sizeof(hdr) ||
78         write(s->fd, buf, caplen) != caplen) {
79         qemu_log("-net dump write error - stop dump\n");
80         close(s->fd);
81         s->fd = -1;
82     }
83 
84     return size;
85 }
86 
dump_cleanup(VLANClientState * nc)87 static void dump_cleanup(VLANClientState *nc)
88 {
89     DumpState *s = DO_UPCAST(DumpState, nc, nc);
90 
91     close(s->fd);
92 }
93 
94 static NetClientInfo net_dump_info = {
95     .type = NET_CLIENT_TYPE_DUMP,
96     .size = sizeof(DumpState),
97     .receive = dump_receive,
98     .cleanup = dump_cleanup,
99 };
100 
net_dump_init(VLANState * vlan,const char * device,const char * name,const char * filename,int len)101 static int net_dump_init(VLANState *vlan, const char *device,
102                          const char *name, const char *filename, int len)
103 {
104     struct pcap_file_hdr hdr;
105     VLANClientState *nc;
106     DumpState *s;
107     int fd;
108 
109     fd = open(filename, O_CREAT | O_WRONLY | O_BINARY, 0644);
110     if (fd < 0) {
111         error_report("-net dump: can't open %s", filename);
112         return -1;
113     }
114 
115     hdr.magic = PCAP_MAGIC;
116     hdr.version_major = 2;
117     hdr.version_minor = 4;
118     hdr.thiszone = 0;
119     hdr.sigfigs = 0;
120     hdr.snaplen = len;
121     hdr.linktype = 1;
122 
123     if (write(fd, &hdr, sizeof(hdr)) < sizeof(hdr)) {
124         error_report("-net dump write error: %s", strerror(errno));
125         close(fd);
126         return -1;
127     }
128 
129     nc = qemu_new_net_client(&net_dump_info, vlan, NULL, device, name);
130 
131     snprintf(nc->info_str, sizeof(nc->info_str),
132              "dump to %s (len=%d)", filename, len);
133 
134     s = DO_UPCAST(DumpState, nc, nc);
135 
136     s->fd = fd;
137     s->pcap_caplen = len;
138 
139     return 0;
140 }
141 
net_init_dump(QemuOpts * opts,Monitor * mon,const char * name,VLANState * vlan)142 int net_init_dump(QemuOpts *opts, Monitor *mon, const char *name, VLANState *vlan)
143 {
144     int len;
145     const char *file;
146     char def_file[128];
147 
148     assert(vlan);
149 
150     file = qemu_opt_get(opts, "file");
151     if (!file) {
152         snprintf(def_file, sizeof(def_file), "qemu-vlan%d.pcap", vlan->id);
153         file = def_file;
154     }
155 
156     len = qemu_opt_get_size(opts, "len", 65536);
157 
158     return net_dump_init(vlan, "dump", name, file, len);
159 }
160