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