bt-host.c

   1 /*
   2  * Wrap a host Bluetooth HCI socket in a struct HCIInfo.
   3  *
   4  * Copyright (C) 2008 Andrzej Zaborowski  <balrog@zabor.org>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation; either version 2 or
   9  * (at your option) version 3 of the License.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "qemu-common.h"
  21 #include "sysemu/bt.h"
  22 #include "qemu/main-loop.h"
  23 #include "qemu/sockets.h"
  24
  25 #ifndef _WIN32
  26 # include <errno.h>
  27 # include <sys/ioctl.h>
  28 # include <sys/uio.h>
  29 # ifdef CONFIG_BLUEZ
  30 #  include <bluetooth/bluetooth.h>
  31 #  include <bluetooth/hci.h>
  32 #  include <bluetooth/hci_lib.h>
  33 # else
  34 #  include "hw/bt.h"
  35 #  define HCI_MAX_FRAME_SIZE    1028
  36 # endif
  37
  38 struct bt_host_hci_s {
  39     struct HCIInfo hci;
  40     int fd;
  41
  42     uint8_t hdr[HCI_MAX_FRAME_SIZE];
  43     int len;
  44 };
  45
  46 static void bt_host_send(struct HCIInfo *hci,
  47                 int type, const uint8_t *data, int len)
  48 {
  49     struct bt_host_hci_s *s = (struct bt_host_hci_s *) hci;
  50     uint8_t pkt = type;
  51     struct iovec iv[2];
  52
  53     iv[0].iov_base = (void *)&pkt;
  54     iv[0].iov_len  = 1;
  55     iv[1].iov_base = (void *) data;
  56     iv[1].iov_len  = len;
  57
  58     while (writev(s->fd, iv, 2) < 0) {
  59         if (errno != EAGAIN && errno != EINTR) {
  60             fprintf(stderr, "qemu: error %i writing bluetooth packet.\n",
  61                             errno);
  62             return;
  63         }
  64     }
  65 }
  66
  67 static void bt_host_cmd(struct HCIInfo *hci, const uint8_t *data, int len)
  68 {
  69     bt_host_send(hci, HCI_COMMAND_PKT, data, len);
  70 }
  71
  72 static void bt_host_acl(struct HCIInfo *hci, const uint8_t *data, int len)
  73 {
  74     bt_host_send(hci, HCI_ACLDATA_PKT, data, len);
  75 }
  76
  77 static void bt_host_sco(struct HCIInfo *hci, const uint8_t *data, int len)
  78 {
  79     bt_host_send(hci, HCI_SCODATA_PKT, data, len);
  80 }
  81
  82 static void bt_host_read(void *opaque)
  83 {
  84     struct bt_host_hci_s *s = (struct bt_host_hci_s *) opaque;
  85     uint8_t *pkt;
  86     int pktlen;
  87
  88     /* Seems that we can't read only the header first and then the amount
  89      * of data indicated in the header because Linux will discard everything
  90      * that's not been read in one go.  */
  91     s->len = read(s->fd, s->hdr, sizeof(s->hdr));
  92
  93     if (s->len < 0) {
  94         fprintf(stderr, "qemu: error %i reading HCI frame\n", errno);
  95         return;
  96     }
  97
  98     pkt = s->hdr;
  99     while (s->len --)
 100         switch (*pkt ++) {
 101         case HCI_EVENT_PKT:
 102             if (s->len < 2)
 103                 goto bad_pkt;
 104
 105             pktlen = MIN(pkt[1] + 2, s->len);
 106             s->hci.evt_recv(s->hci.opaque, pkt, pktlen);
 107             s->len -= pktlen;
 108             pkt += pktlen;
 109
 110             /* TODO: if this is an Inquiry Result event, it's also
 111              * interpreted by Linux kernel before we received it, possibly
 112              * we should clean the kernel Inquiry cache through
 113              * ioctl(s->fd, HCI_INQUIRY, ...).  */
 114             break;
 115
 116         case HCI_ACLDATA_PKT:
 117             if (s->len < 4)
 118                 goto bad_pkt;
 119
 120             pktlen = MIN(((pkt[3] << 8) | pkt[2]) + 4, s->len);
 121             s->hci.acl_recv(s->hci.opaque, pkt, pktlen);
 122             s->len -= pktlen;
 123             pkt += pktlen;
 124             break;
 125
 126         case HCI_SCODATA_PKT:
 127             if (s->len < 3)
 128                 goto bad_pkt;
 129
 130             pktlen = MIN(pkt[2] + 3, s->len);
 131             s->len -= pktlen;
 132             pkt += pktlen;
 133             break;
 134
 135         default:
 136         bad_pkt:
 137             fprintf(stderr, "qemu: bad HCI packet type %02x\n", pkt[-1]);
 138         }
 139 }
 140
 141 static int bt_host_bdaddr_set(struct HCIInfo *hci, const uint8_t *bd_addr)
 142 {
 143     return -ENOTSUP;
 144 }
 145
 146 struct HCIInfo *bt_host_hci(const char *id)
 147 {
 148     struct bt_host_hci_s *s;
 149     int fd = -1;
 150 # ifdef CONFIG_BLUEZ
 151     int dev_id = hci_devid(id);
 152     struct hci_filter flt;
 153
 154     if (dev_id < 0) {
 155         fprintf(stderr, "qemu: `%s' not available\n", id);
 156         return 0;
 157     }
 158
 159     fd = hci_open_dev(dev_id);
 160
 161     /* XXX: can we ensure nobody else has the device opened?  */
 162 # endif
 163
 164     if (fd < 0) {
 165         fprintf(stderr, "qemu: Can't open `%s': %s (%i)\n",
 166                         id, strerror(errno), errno);
 167         return NULL;
 168     }
 169
 170 # ifdef CONFIG_BLUEZ
 171     hci_filter_clear(&flt);
 172     hci_filter_all_ptypes(&flt);
 173     hci_filter_all_events(&flt);
 174
 175     if (qemu_setsockopt(fd, SOL_HCI, HCI_FILTER, &flt, sizeof(flt)) < 0) {
 176         fprintf(stderr, "qemu: Can't set HCI filter on socket (%i)\n", errno);
 177         return 0;
 178     }
 179 # endif
 180
 181     s = g_malloc0(sizeof(struct bt_host_hci_s));
 182     s->fd = fd;
 183     s->hci.cmd_send = bt_host_cmd;
 184     s->hci.sco_send = bt_host_sco;
 185     s->hci.acl_send = bt_host_acl;
 186     s->hci.bdaddr_set = bt_host_bdaddr_set;
 187
 188     qemu_set_fd_handler(s->fd, bt_host_read, NULL, s);
 189
 190     return &s->hci;
 191 }
 192 #else
 193 struct HCIInfo *bt_host_hci(const char *id)
 194 {
 195     fprintf(stderr, "qemu: bluetooth passthrough not supported (yet)\n");
 196
 197     return 0;
 198 }
 199 #endif