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 "bt/bt.h"
  22 #include "qemu/main-loop.h"
  23
  24 #ifndef _WIN32
  25 # include <errno.h>
  26 # include <sys/ioctl.h>
  27 # include <sys/uio.h>
  28 # ifdef CONFIG_BLUEZ
  29 #  include <bluetooth/bluetooth.h>
  30 #  include <bluetooth/hci.h>
  31 #  include <bluetooth/hci_lib.h>
  32 # else
  33 #  include "hw/bt.h"
  34 #  define HCI_MAX_FRAME_SIZE    1028
  35 # endif
  36
  37 struct bt_host_hci_s {
  38     struct HCIInfo hci;
  39     int fd;
  40
  41     uint8_t hdr[HCI_MAX_FRAME_SIZE];
  42     int len;
  43 };
  44
  45 static void bt_host_send(struct HCIInfo *hci,
  46                 int type, const uint8_t *data, int len)
  47 {
  48     struct bt_host_hci_s *s = (struct bt_host_hci_s *) hci;
  49     uint8_t pkt = type;
  50     struct iovec iv[2];
  51
  52     iv[0].iov_base = (void *)&pkt;
  53     iv[0].iov_len  = 1;
  54     iv[1].iov_base = (void *) data;
  55     iv[1].iov_len  = len;
  56
  57     while (writev(s->fd, iv, 2) < 0) {
  58         if (errno != EAGAIN && errno != EINTR) {
  59             fprintf(stderr, "qemu: error %i writing bluetooth packet.\n",
  60                             errno);
  61             return;
  62         }
  63     }
  64 }
  65
  66 static void bt_host_cmd(struct HCIInfo *hci, const uint8_t *data, int len)
  67 {
  68     bt_host_send(hci, HCI_COMMAND_PKT, data, len);
  69 }
  70
  71 static void bt_host_acl(struct HCIInfo *hci, const uint8_t *data, int len)
  72 {
  73     bt_host_send(hci, HCI_ACLDATA_PKT, data, len);
  74 }
  75
  76 static void bt_host_sco(struct HCIInfo *hci, const uint8_t *data, int len)
  77 {
  78     bt_host_send(hci, HCI_SCODATA_PKT, data, len);
  79 }
  80
  81 static void bt_host_read(void *opaque)
  82 {
  83     struct bt_host_hci_s *s = (struct bt_host_hci_s *) opaque;
  84     uint8_t *pkt;
  85     int pktlen;
  86
  87     /* Seems that we can't read only the header first and then the amount
  88      * of data indicated in the header because Linux will discard everything
  89      * that's not been read in one go.  */
  90     s->len = read(s->fd, s->hdr, sizeof(s->hdr));
  91
  92     if (s->len < 0) {
  93         fprintf(stderr, "qemu: error %i reading HCI frame\n", errno);
  94         return;
  95     }
  96
  97     pkt = s->hdr;
  98     while (s->len --)
  99         switch (*pkt ++) {
 100         case HCI_EVENT_PKT:
 101             if (s->len < 2)
 102                 goto bad_pkt;
 103
 104             pktlen = MIN(pkt[1] + 2, s->len);
 105             s->hci.evt_recv(s->hci.opaque, pkt, pktlen);
 106             s->len -= pktlen;
 107             pkt += pktlen;
 108
 109             /* TODO: if this is an Inquiry Result event, it's also
 110              * interpreted by Linux kernel before we received it, possibly
 111              * we should clean the kernel Inquiry cache through
 112              * ioctl(s->fd, HCI_INQUIRY, ...).  */
 113             break;
 114
 115         case HCI_ACLDATA_PKT:
 116             if (s->len < 4)
 117                 goto bad_pkt;
 118
 119             pktlen = MIN(((pkt[3] << 8) | pkt[2]) + 4, s->len);
 120             s->hci.acl_recv(s->hci.opaque, pkt, pktlen);
 121             s->len -= pktlen;
 122             pkt += pktlen;
 123             break;
 124
 125         case HCI_SCODATA_PKT:
 126             if (s->len < 3)
 127                 goto bad_pkt;
 128
 129             pktlen = MIN(pkt[2] + 3, s->len);
 130             s->len -= pktlen;
 131             pkt += pktlen;
 132             break;
 133
 134         default:
 135         bad_pkt:
 136             fprintf(stderr, "qemu: bad HCI packet type %02x\n", pkt[-1]);
 137         }
 138 }
 139
 140 static int bt_host_bdaddr_set(struct HCIInfo *hci, const uint8_t *bd_addr)
 141 {
 142     return -ENOTSUP;
 143 }
 144
 145 struct HCIInfo *bt_host_hci(const char *id)
 146 {
 147     struct bt_host_hci_s *s;
 148     int fd = -1;
 149 # ifdef CONFIG_BLUEZ
 150     int dev_id = hci_devid(id);
 151     struct hci_filter flt;
 152
 153     if (dev_id < 0) {
 154         fprintf(stderr, "qemu: `%s' not available\n", id);
 155         return 0;
 156     }
 157
 158     fd = hci_open_dev(dev_id);
 159
 160     /* XXX: can we ensure nobody else has the device opened?  */
 161 # endif
 162
 163     if (fd < 0) {
 164         fprintf(stderr, "qemu: Can't open `%s': %s (%i)\n",
 165                         id, strerror(errno), errno);
 166         return NULL;
 167     }
 168
 169 # ifdef CONFIG_BLUEZ
 170     hci_filter_clear(&flt);
 171     hci_filter_all_ptypes(&flt);
 172     hci_filter_all_events(&flt);
 173
 174     if (qemu_setsockopt(fd, SOL_HCI, HCI_FILTER, &flt, sizeof(flt)) < 0) {
 175         fprintf(stderr, "qemu: Can't set HCI filter on socket (%i)\n", errno);
 176         return 0;
 177     }
 178 # endif
 179
 180     s = g_malloc0(sizeof(struct bt_host_hci_s));
 181     s->fd = fd;
 182     s->hci.cmd_send = bt_host_cmd;
 183     s->hci.sco_send = bt_host_sco;
 184     s->hci.acl_send = bt_host_acl;
 185     s->hci.bdaddr_set = bt_host_bdaddr_set;
 186
 187     qemu_set_fd_handler(s->fd, bt_host_read, NULL, s);
 188
 189     return &s->hci;
 190 }
 191 #else
 192 struct HCIInfo *bt_host_hci(const char *id)
 193 {
 194     fprintf(stderr, "qemu: bluetooth passthrough not supported (yet)\n");
 195
 196     return 0;
 197 }
 198 #endif