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/module.h"
  30 #include "qemu/option.h"
  31
  32 #include "chardev/char-io.h"
  33 #include "qom/object.h"
  34
  35 /***********************************************************/
  36 /* UDP Net console */
  37
  38 struct UdpChardev {
  39     Chardev parent;
  40     QIOChannel *ioc;
  41     uint8_t buf[CHR_READ_BUF_LEN];
  42     int bufcnt;
  43     int bufptr;
  44     int max_size;
  45 };
  46 typedef struct UdpChardev UdpChardev;
  47
  48 DECLARE_INSTANCE_CHECKER(UdpChardev, UDP_CHARDEV,
  49                          TYPE_CHARDEV_UDP)
  50
  51 /* Called with chr_write_lock held.  */
  52 static int udp_chr_write(Chardev *chr, const uint8_t *buf, int len)
  53 {
  54     UdpChardev *s = UDP_CHARDEV(chr);
  55
  56     return qio_channel_write(
  57         s->ioc, (const char *)buf, len, NULL);
  58 }
  59
  60 static void udp_chr_flush_buffer(UdpChardev *s)
  61 {
  62     Chardev *chr = CHARDEV(s);
  63
  64     while (s->max_size > 0 && s->bufptr < s->bufcnt) {
  65         int n = MIN(s->max_size, s->bufcnt - s->bufptr);
  66         qemu_chr_be_write(chr, &s->buf[s->bufptr], n);
  67         s->bufptr += n;
  68         s->max_size = qemu_chr_be_can_write(chr);
  69     }
  70 }
  71
  72 static int udp_chr_read_poll(void *opaque)
  73 {
  74     Chardev *chr = CHARDEV(opaque);
  75     UdpChardev *s = UDP_CHARDEV(opaque);
  76
  77     s->max_size = qemu_chr_be_can_write(chr);
  78
  79     /* If there were any stray characters in the queue process them
  80      * first
  81      */
  82     udp_chr_flush_buffer(s);
  83
  84     return s->max_size;
  85 }
  86
  87 static gboolean udp_chr_read(QIOChannel *chan, GIOCondition cond, void *opaque)
  88 {
  89     Chardev *chr = CHARDEV(opaque);
  90     UdpChardev *s = UDP_CHARDEV(opaque);
  91     ssize_t ret;
  92
  93     if (s->max_size == 0) {
  94         return TRUE;
  95     }
  96     ret = qio_channel_read(
  97         s->ioc, (char *)s->buf, sizeof(s->buf), NULL);
  98     if (ret <= 0) {
  99         remove_fd_in_watch(chr);
 100         return FALSE;
 101     }
 102     s->bufcnt = ret;
 103     s->bufptr = 0;
 104     udp_chr_flush_buffer(s);
 105
 106     return TRUE;
 107 }
 108
 109 static void udp_chr_update_read_handler(Chardev *chr)
 110 {
 111     UdpChardev *s = UDP_CHARDEV(chr);
 112
 113     remove_fd_in_watch(chr);
 114     if (s->ioc) {
 115         chr->gsource = io_add_watch_poll(chr, s->ioc,
 116                                            udp_chr_read_poll,
 117                                            udp_chr_read, chr,
 118                                            chr->gcontext);
 119     }
 120 }
 121
 122 static void char_udp_finalize(Object *obj)
 123 {
 124     Chardev *chr = CHARDEV(obj);
 125     UdpChardev *s = UDP_CHARDEV(obj);
 126
 127     remove_fd_in_watch(chr);
 128     if (s->ioc) {
 129         object_unref(OBJECT(s->ioc));
 130     }
 131     qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
 132 }
 133
 134 static void qemu_chr_parse_udp(QemuOpts *opts, ChardevBackend *backend,
 135                                Error **errp)
 136 {
 137     const char *host = qemu_opt_get(opts, "host");
 138     const char *port = qemu_opt_get(opts, "port");
 139     const char *localaddr = qemu_opt_get(opts, "localaddr");
 140     const char *localport = qemu_opt_get(opts, "localport");
 141     bool has_local = false;
 142     SocketAddressLegacy *addr;
 143     ChardevUdp *udp;
 144
 145     backend->type = CHARDEV_BACKEND_KIND_UDP;
 146     if (host == NULL || strlen(host) == 0) {
 147         host = "localhost";
 148     }
 149     if (port == NULL || strlen(port) == 0) {
 150         error_setg(errp, "chardev: udp: remote port not specified");
 151         return;
 152     }
 153     if (localport == NULL || strlen(localport) == 0) {
 154         localport = "0";
 155     } else {
 156         has_local = true;
 157     }
 158     if (localaddr == NULL || strlen(localaddr) == 0) {
 159         localaddr = "";
 160     } else {
 161         has_local = true;
 162     }
 163
 164     udp = backend->u.udp.data = g_new0(ChardevUdp, 1);
 165     qemu_chr_parse_common(opts, qapi_ChardevUdp_base(udp));
 166
 167     addr = g_new0(SocketAddressLegacy, 1);
 168     addr->type = SOCKET_ADDRESS_TYPE_INET;
 169     addr->u.inet.data = g_new(InetSocketAddress, 1);
 170     *addr->u.inet.data = (InetSocketAddress) {
 171         .host = g_strdup(host),
 172         .port = g_strdup(port),
 173         .has_ipv4 = qemu_opt_get(opts, "ipv4"),
 174         .ipv4 = qemu_opt_get_bool(opts, "ipv4", 0),
 175         .has_ipv6 = qemu_opt_get(opts, "ipv6"),
 176         .ipv6 = qemu_opt_get_bool(opts, "ipv6", 0),
 177     };
 178     udp->remote = addr;
 179
 180     if (has_local) {
 181         udp->has_local = true;
 182         addr = g_new0(SocketAddressLegacy, 1);
 183         addr->type = SOCKET_ADDRESS_TYPE_INET;
 184         addr->u.inet.data = g_new(InetSocketAddress, 1);
 185         *addr->u.inet.data = (InetSocketAddress) {
 186             .host = g_strdup(localaddr),
 187             .port = g_strdup(localport),
 188         };
 189         udp->local = addr;
 190     }
 191 }
 192
 193 static void qmp_chardev_open_udp(Chardev *chr,
 194                                  ChardevBackend *backend,
 195                                  bool *be_opened,
 196                                  Error **errp)
 197 {
 198     ChardevUdp *udp = backend->u.udp.data;
 199     SocketAddress *local_addr = socket_address_flatten(udp->local);
 200     SocketAddress *remote_addr = socket_address_flatten(udp->remote);
 201     QIOChannelSocket *sioc = qio_channel_socket_new();
 202     char *name;
 203     UdpChardev *s = UDP_CHARDEV(chr);
 204     int ret;
 205
 206     ret = qio_channel_socket_dgram_sync(sioc, local_addr, remote_addr, errp);
 207     qapi_free_SocketAddress(local_addr);
 208     qapi_free_SocketAddress(remote_addr);
 209     if (ret < 0) {
 210         object_unref(OBJECT(sioc));
 211         return;
 212     }
 213
 214     name = g_strdup_printf("chardev-udp-%s", chr->label);
 215     qio_channel_set_name(QIO_CHANNEL(sioc), name);
 216     g_free(name);
 217
 218     s->ioc = QIO_CHANNEL(sioc);
 219     /* be isn't opened until we get a connection */
 220     *be_opened = false;
 221 }
 222
 223 static void char_udp_class_init(ObjectClass *oc, void *data)
 224 {
 225     ChardevClass *cc = CHARDEV_CLASS(oc);
 226
 227     cc->parse = qemu_chr_parse_udp;
 228     cc->open = qmp_chardev_open_udp;
 229     cc->chr_write = udp_chr_write;
 230     cc->chr_update_read_handler = udp_chr_update_read_handler;
 231 }
 232
 233 static const TypeInfo char_udp_type_info = {
 234     .name = TYPE_CHARDEV_UDP,
 235     .parent = TYPE_CHARDEV,
 236     .instance_size = sizeof(UdpChardev),
 237     .instance_finalize = char_udp_finalize,
 238     .class_init = char_udp_class_init,
 239 };
 240
 241 static void register_types(void)
 242 {
 243     type_register_static(&char_udp_type_info);
 244 }
 245
 246 type_init(register_types);