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