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