summaryrefslogtreecommitdiff
path: root/net/hub.c
blob: ee9d878313f5cf6df60851d63caeca68aa8988cf (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
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
/*
 * Hub net client
 *
 * Copyright IBM, Corp. 2012
 *
 * Authors:
 *  Stefan Hajnoczi   <stefanha@linux.vnet.ibm.com>
 *  Zhi Yong Wu       <wuzhy@linux.vnet.ibm.com>
 *
 * This work is licensed under the terms of the GNU LGPL, version 2 or later.
 * See the COPYING.LIB file in the top-level directory.
 *
 */

#include "monitor.h"
#include "net.h"
#include "hub.h"

/*
 * A hub broadcasts incoming packets to all its ports except the source port.
 * Hubs can be used to provide independent network segments, also confusingly
 * named the QEMU 'vlan' feature.
 */

typedef struct NetHub NetHub;

typedef struct NetHubPort {
    VLANClientState nc;
    QLIST_ENTRY(NetHubPort) next;
    NetHub *hub;
    int id;
} NetHubPort;

struct NetHub {
    int id;
    QLIST_ENTRY(NetHub) next;
    int num_ports;
    QLIST_HEAD(, NetHubPort) ports;
};

static QLIST_HEAD(, NetHub) hubs = QLIST_HEAD_INITIALIZER(&hubs);

static ssize_t net_hub_receive(NetHub *hub, NetHubPort *source_port,
                               const uint8_t *buf, size_t len)
{
    NetHubPort *port;

    QLIST_FOREACH(port, &hub->ports, next) {
        if (port == source_port) {
            continue;
        }

        qemu_send_packet(&port->nc, buf, len);
    }
    return len;
}

static ssize_t net_hub_receive_iov(NetHub *hub, NetHubPort *source_port,
                                   const struct iovec *iov, int iovcnt)
{
    NetHubPort *port;
    ssize_t ret = 0;

    QLIST_FOREACH(port, &hub->ports, next) {
        if (port == source_port) {
            continue;
        }

        ret = qemu_sendv_packet(&port->nc, iov, iovcnt);
    }
    return ret;
}

static NetHub *net_hub_new(int id)
{
    NetHub *hub;

    hub = g_malloc(sizeof(*hub));
    hub->id = id;
    hub->num_ports = 0;
    QLIST_INIT(&hub->ports);

    QLIST_INSERT_HEAD(&hubs, hub, next);

    return hub;
}

static ssize_t net_hub_port_receive(VLANClientState *nc,
                                    const uint8_t *buf, size_t len)
{
    NetHubPort *port = DO_UPCAST(NetHubPort, nc, nc);

    return net_hub_receive(port->hub, port, buf, len);
}

static ssize_t net_hub_port_receive_iov(VLANClientState *nc,
                                        const struct iovec *iov, int iovcnt)
{
    NetHubPort *port = DO_UPCAST(NetHubPort, nc, nc);

    return net_hub_receive_iov(port->hub, port, iov, iovcnt);
}

static void net_hub_port_cleanup(VLANClientState *nc)
{
    NetHubPort *port = DO_UPCAST(NetHubPort, nc, nc);

    QLIST_REMOVE(port, next);
}

static NetClientInfo net_hub_port_info = {
    .type = NET_CLIENT_OPTIONS_KIND_HUBPORT,
    .size = sizeof(NetHubPort),
    .receive = net_hub_port_receive,
    .receive_iov = net_hub_port_receive_iov,
    .cleanup = net_hub_port_cleanup,
};

static NetHubPort *net_hub_port_new(NetHub *hub, const char *name)
{
    VLANClientState *nc;
    NetHubPort *port;
    int id = hub->num_ports++;
    char default_name[128];

    if (!name) {
        snprintf(default_name, sizeof(default_name),
                 "hub%dport%d", hub->id, id);
        name = default_name;
    }

    nc = qemu_new_net_client(&net_hub_port_info, NULL, NULL, "hub", name);
    port = DO_UPCAST(NetHubPort, nc, nc);
    port->id = id;
    port->hub = hub;

    QLIST_INSERT_HEAD(&hub->ports, port, next);

    return port;
}

/**
 * Create a port on a given hub
 * @name: Net client name or NULL for default name.
 *
 * If there is no existing hub with the given id then a new hub is created.
 */
VLANClientState *net_hub_add_port(int hub_id, const char *name)
{
    NetHub *hub;
    NetHubPort *port;

    QLIST_FOREACH(hub, &hubs, next) {
        if (hub->id == hub_id) {
            break;
        }
    }

    if (!hub) {
        hub = net_hub_new(hub_id);
    }

    port = net_hub_port_new(hub, name);
    return &port->nc;
}

/**
 * Print hub configuration
 */
void net_hub_info(Monitor *mon)
{
    NetHub *hub;
    NetHubPort *port;

    QLIST_FOREACH(hub, &hubs, next) {
        monitor_printf(mon, "hub %d\n", hub->id);
        QLIST_FOREACH(port, &hub->ports, next) {
            monitor_printf(mon, "    port %d peer %s\n", port->id,
                           port->nc.peer ? port->nc.peer->name : "<none>");
        }
    }
}

/**
 * Get the hub id that a client is connected to
 *
 * @id              Pointer for hub id output, may be NULL
 */
int net_hub_id_for_client(VLANClientState *nc, int *id)
{
    NetHubPort *port;

    if (nc->info->type == NET_CLIENT_OPTIONS_KIND_HUBPORT) {
        port = DO_UPCAST(NetHubPort, nc, nc);
    } else if (nc->peer != NULL && nc->peer->info->type ==
            NET_CLIENT_OPTIONS_KIND_HUBPORT) {
        port = DO_UPCAST(NetHubPort, nc, nc->peer);
    } else {
        return -ENOENT;
    }

    if (id) {
        *id = port->hub->id;
    }
    return 0;
}

int net_init_hubport(const NetClientOptions *opts, const char *name,
                     VLANClientState *peer)
{
    const NetdevHubPortOptions *hubport;

    assert(opts->kind == NET_CLIENT_OPTIONS_KIND_HUBPORT);
    hubport = opts->hubport;

    /* Treat hub port like a backend, NIC must be the one to peer */
    if (peer) {
        return -EINVAL;
    }

    net_hub_add_port(hubport->hubid, name);
    return 0;
}