chardev/char-udp.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 "chardev/char.h"
  27 #include "io/channel-socket.h"
  28 #include "qapi/error.h"
  29 #include "qemu/option.h"
  30
  31 #include "chardev/char-io.h"
  32
  33 /***********************************************************/
  34 /* UDP Net console */
  35
  36 typedef struct {
  37     Chardev parent;
  38     QIOChannel *ioc;
  39     uint8_t buf[CHR_READ_BUF_LEN];
  40     int bufcnt;
  41     int bufptr;
  42     int max_size;
  43 } UdpChardev;
  44
  45 #define UDP_CHARDEV(obj) OBJECT_CHECK(UdpChardev, (obj), TYPE_CHARDEV_UDP)
  46
  47 /* Called with chr_write_lock held.  */
  48 static int udp_chr_write(Chardev *chr, const uint8_t *buf, int len)
  49 {
  50     UdpChardev *s = UDP_CHARDEV(chr);
  51
  52     return qio_channel_write(
  53         s->ioc, (const char *)buf, len, NULL);
  54 }
  55
  56 static void udp_chr_flush_buffer(UdpChardev *s)
  57 {
  58     Chardev *chr = CHARDEV(s);
  59
  60     while (s->max_size > 0 && s->bufptr < s->bufcnt) {
  61         int n = MIN(s->max_size, s->bufcnt - s->bufptr);
  62         qemu_chr_be_write(chr, &s->buf[s->bufptr], n);
  63         s->bufptr += n;
  64         s->max_size = qemu_chr_be_can_write(chr);
  65     }
  66 }
  67
  68 static int udp_chr_read_poll(void *opaque)
  69 {
  70     Chardev *chr = CHARDEV(opaque);
  71     UdpChardev *s = UDP_CHARDEV(opaque);
  72
  73     s->max_size = qemu_chr_be_can_write(chr);
  74
  75     /* If there were any stray characters in the queue process them
  76      * first
  77      */
  78     udp_chr_flush_buffer(s);
  79
  80     return s->max_size;
  81 }
  82
  83 static gboolean udp_chr_read(QIOChannel *chan, GIOCondition cond, void *opaque)
  84 {
  85     Chardev *chr = CHARDEV(opaque);
  86     UdpChardev *s = UDP_CHARDEV(opaque);
  87     ssize_t ret;
  88
  89     if (s->max_size == 0) {
  90         return TRUE;
  91     }
  92     ret = qio_channel_read(
  93         s->ioc, (char *)s->buf, sizeof(s->buf), NULL);
  94     if (ret <= 0) {
  95         remove_fd_in_watch(chr);
  96         return FALSE;
  97     }
  98     s->bufcnt = ret;
  99     s->bufptr = 0;
 100     udp_chr_flush_buffer(s);
 101
 102     return TRUE;
 103 }
 104
 105 static void udp_chr_update_read_handler(Chardev *chr)
 106 {
 107     UdpChardev *s = UDP_CHARDEV(chr);
 108
 109     remove_fd_in_watch(chr);
 110     if (s->ioc) {
 111         chr->gsource = io_add_watch_poll(chr, s->ioc,
 112                                            udp_chr_read_poll,
 113                                            udp_chr_read, chr,
 114                                            chr->gcontext);
 115     }
 116 }
 117
 118 static void char_udp_finalize(Object *obj)
 119 {
 120     Chardev *chr = CHARDEV(obj);
 121     UdpChardev *s = UDP_CHARDEV(obj);
 122
 123     remove_fd_in_watch(chr);
 124     if (s->ioc) {
 125         object_unref(OBJECT(s->ioc));
 126     }
 127     qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
 128 }
 129
 130 static void qemu_chr_parse_udp(QemuOpts *opts, ChardevBackend *backend,
 131                                Error **errp)
 132 {
 133     const char *host = qemu_opt_get(opts, "host");
 134     const char *port = qemu_opt_get(opts, "port");
 135     const char *localaddr = qemu_opt_get(opts, "localaddr");
 136     const char *localport = qemu_opt_get(opts, "localport");
 137     bool has_local = false;
 138     SocketAddressLegacy *addr;
 139     ChardevUdp *udp;
 140
 141     backend->type = CHARDEV_BACKEND_KIND_UDP;
 142     if (host == NULL || strlen(host) == 0) {
 143         host = "localhost";
 144     }
 145     if (port == NULL || strlen(port) == 0) {
 146         error_setg(errp, "chardev: udp: remote port not specified");
 147         return;
 148     }
 149     if (localport == NULL || strlen(localport) == 0) {
 150         localport = "0";
 151     } else {
 152         has_local = true;
 153     }
 154     if (localaddr == NULL || strlen(localaddr) == 0) {
 155         localaddr = "";
 156     } else {
 157         has_local = true;
 158     }
 159
 160     udp = backend->u.udp.data = g_new0(ChardevUdp, 1);
 161     qemu_chr_parse_common(opts, qapi_ChardevUdp_base(udp));
 162
 163     addr = g_new0(SocketAddressLegacy, 1);
 164     addr->type = SOCKET_ADDRESS_LEGACY_KIND_INET;
 165     addr->u.inet.data = g_new(InetSocketAddress, 1);
 166     *addr->u.inet.data = (InetSocketAddress) {
 167         .host = g_strdup(host),
 168         .port = g_strdup(port),
 169         .has_ipv4 = qemu_opt_get(opts, "ipv4"),
 170         .ipv4 = qemu_opt_get_bool(opts, "ipv4", 0),
 171         .has_ipv6 = qemu_opt_get(opts, "ipv6"),
 172         .ipv6 = qemu_opt_get_bool(opts, "ipv6", 0),
 173     };
 174     udp->remote = addr;
 175
 176     if (has_local) {
 177         udp->has_local = true;
 178         addr = g_new0(SocketAddressLegacy, 1);
 179         addr->type = SOCKET_ADDRESS_LEGACY_KIND_INET;
 180         addr->u.inet.data = g_new(InetSocketAddress, 1);
 181         *addr->u.inet.data = (InetSocketAddress) {
 182             .host = g_strdup(localaddr),
 183             .port = g_strdup(localport),
 184         };
 185         udp->local = addr;
 186     }
 187 }
 188
 189 static void qmp_chardev_open_udp(Chardev *chr,
 190                                  ChardevBackend *backend,
 191                                  bool *be_opened,
 192                                  Error **errp)
 193 {
 194     ChardevUdp *udp = backend->u.udp.data;
 195     SocketAddress *local_addr = socket_address_flatten(udp->local);
 196     SocketAddress *remote_addr = socket_address_flatten(udp->remote);
 197     QIOChannelSocket *sioc = qio_channel_socket_new();
 198     char *name;
 199     UdpChardev *s = UDP_CHARDEV(chr);
 200     int ret;
 201
 202     ret = qio_channel_socket_dgram_sync(sioc, local_addr, remote_addr, errp);
 203     qapi_free_SocketAddress(local_addr);
 204     qapi_free_SocketAddress(remote_addr);
 205     if (ret < 0) {
 206         object_unref(OBJECT(sioc));
 207         return;
 208     }
 209
 210     name = g_strdup_printf("chardev-udp-%s", chr->label);
 211     qio_channel_set_name(QIO_CHANNEL(sioc), name);
 212     g_free(name);
 213
 214     s->ioc = QIO_CHANNEL(sioc);
 215     /* be isn't opened until we get a connection */
 216     *be_opened = false;
 217 }
 218
 219 static void char_udp_class_init(ObjectClass *oc, void *data)
 220 {
 221     ChardevClass *cc = CHARDEV_CLASS(oc);
 222
 223     cc->parse = qemu_chr_parse_udp;
 224     cc->open = qmp_chardev_open_udp;
 225     cc->chr_write = udp_chr_write;
 226     cc->chr_update_read_handler = udp_chr_update_read_handler;
 227 }
 228
 229 static const TypeInfo char_udp_type_info = {
 230     .name = TYPE_CHARDEV_UDP,
 231     .parent = TYPE_CHARDEV,
 232     .instance_size = sizeof(UdpChardev),
 233     .instance_finalize = char_udp_finalize,
 234     .class_init = char_udp_class_init,
 235 };
 236
 237 static void register_types(void)
 238 {
 239     type_register_static(&char_udp_type_info);
 240 }
 241
 242 type_init(register_types);