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, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #include "qemu-common.h"
  22 #include "qemu-char.h"
  23 #include "sysemu.h"
  24 #include "net.h"
  25 #include "bt-host.h"
  26
  27 #ifndef _WIN32
  28 # include <errno.h>
  29 # include <sys/ioctl.h>
  30 # include <sys/uio.h>
  31 # ifdef CONFIG_BLUEZ
  32 #  include <bluetooth/bluetooth.h>
  33 #  include <bluetooth/hci.h>
  34 #  include <bluetooth/hci_lib.h>
  35 # else
  36 #  include "hw/bt.h"
  37 #  define HCI_MAX_FRAME_SIZE    1028
  38 # endif
  39
  40 struct bt_host_hci_s {
  41     struct HCIInfo hci;
  42     int fd;
  43
  44     uint8_t hdr[HCI_MAX_FRAME_SIZE];
  45     int len;
  46 };
  47
  48 static void bt_host_send(struct HCIInfo *hci,
  49                 int type, const uint8_t *data, int len)
  50 {
  51     struct bt_host_hci_s *s = (struct bt_host_hci_s *) hci;
  52     uint8_t pkt = type;
  53     struct iovec iv[2];
  54     int ret;
  55
  56     iv[0].iov_base = (void *)&pkt;
  57     iv[0].iov_len  = 1;
  58     iv[1].iov_base = (void *) data;
  59     iv[1].iov_len  = len;
  60
  61     while ((ret = writev(s->fd, iv, 2)) < 0)
  62         if (errno != EAGAIN && errno != EINTR) {
  63             fprintf(stderr, "qemu: error %i writing bluetooth packet.\n",
  64                             errno);
  65             return;
  66         }
  67 }
  68
  69 static void bt_host_cmd(struct HCIInfo *hci, const uint8_t *data, int len)
  70 {
  71     bt_host_send(hci, HCI_COMMAND_PKT, data, len);
  72 }
  73
  74 static void bt_host_acl(struct HCIInfo *hci, const uint8_t *data, int len)
  75 {
  76     bt_host_send(hci, HCI_ACLDATA_PKT, data, len);
  77 }
  78
  79 static void bt_host_sco(struct HCIInfo *hci, const uint8_t *data, int len)
  80 {
  81     bt_host_send(hci, HCI_SCODATA_PKT, data, len);
  82 }
  83
  84 static int bt_host_read_poll(void *opaque)
  85 {
  86     struct bt_host_hci_s *s = (struct bt_host_hci_s *) opaque;
  87
  88     return !!s->hci.evt_recv;
  89 }
  90
  91 static void bt_host_read(void *opaque)
  92 {
  93     struct bt_host_hci_s *s = (struct bt_host_hci_s *) opaque;
  94     uint8_t *pkt;
  95     int pktlen;
  96
  97     /* Seems that we can't read only the header first and then the amount
  98      * of data indicated in the header because Linux will discard everything
  99      * that's not been read in one go.  */
 100     s->len = read(s->fd, s->hdr, sizeof(s->hdr));
 101
 102     if (s->len < 0) {
 103         fprintf(stderr, "qemu: error %i reading HCI frame\n", errno);
 104         return;
 105     }
 106
 107     pkt = s->hdr;
 108     while (s->len --)
 109         switch (*pkt ++) {
 110         case HCI_EVENT_PKT:
 111             if (s->len < 2)
 112                 goto bad_pkt;
 113
 114             pktlen = MIN(pkt[1] + 2, s->len);
 115             s->hci.evt_recv(s->hci.opaque, pkt, pktlen);
 116             s->len -= pktlen;
 117             pkt += pktlen;
 118
 119             /* TODO: if this is an Inquiry Result event, it's also
 120              * interpreted by Linux kernel before we received it, possibly
 121              * we should clean the kernel Inquiry cache through
 122              * ioctl(s->fd, HCI_INQUIRY, ...).  */
 123             break;
 124
 125         case HCI_ACLDATA_PKT:
 126             if (s->len < 4)
 127                 goto bad_pkt;
 128
 129             pktlen = MIN(((pkt[3] << 8) | pkt[2]) + 4, s->len);
 130             s->hci.acl_recv(s->hci.opaque, pkt, pktlen);
 131             s->len -= pktlen;
 132             pkt += pktlen;
 133             break;
 134
 135         case HCI_SCODATA_PKT:
 136             if (s->len < 3)
 137                 goto bad_pkt;
 138
 139             pktlen = MIN(pkt[2] + 3, s->len);
 140             s->len -= pktlen;
 141             pkt += pktlen;
 142
 143         default:
 144         bad_pkt:
 145             fprintf(stderr, "qemu: bad HCI packet type %02x\n", pkt[-1]);
 146         }
 147 }
 148
 149 static int bt_host_bdaddr_set(struct HCIInfo *hci, const uint8_t *bd_addr)
 150 {
 151     return -ENOTSUP;
 152 }
 153
 154 struct HCIInfo *bt_host_hci(const char *id)
 155 {
 156     struct bt_host_hci_s *s;
 157     int fd = -1;
 158 # ifdef CONFIG_BLUEZ
 159     int dev_id = hci_devid(id);
 160     struct hci_filter flt;
 161
 162     if (dev_id < 0) {
 163         fprintf(stderr, "qemu: `%s' not available\n", id);
 164         return 0;
 165     }
 166
 167     fd = hci_open_dev(dev_id);
 168
 169     /* XXX: can we ensure nobody else has the device opened?  */
 170 # endif
 171
 172     if (fd < 0) {
 173         fprintf(stderr, "qemu: Can't open `%s': %s (%i)\n",
 174                         id, strerror(errno), errno);
 175         return NULL;
 176     }
 177
 178 # ifdef CONFIG_BLUEZ
 179     hci_filter_clear(&flt);
 180     hci_filter_all_ptypes(&flt);
 181     hci_filter_all_events(&flt);
 182
 183     if (setsockopt(fd, SOL_HCI, HCI_FILTER, &flt, sizeof(flt)) < 0) {
 184         fprintf(stderr, "qemu: Can't set HCI filter on socket (%i)\n", errno);
 185         return 0;
 186     }
 187 # endif
 188
 189     s = qemu_mallocz(sizeof(struct bt_host_hci_s));
 190     s->fd = fd;
 191     s->hci.cmd_send = bt_host_cmd;
 192     s->hci.sco_send = bt_host_sco;
 193     s->hci.acl_send = bt_host_acl;
 194     s->hci.bdaddr_set = bt_host_bdaddr_set;
 195
 196     qemu_set_fd_handler2(s->fd, bt_host_read_poll, bt_host_read, NULL, s);
 197
 198     return &s->hci;
 199 }
 200 #else
 201 struct HCIInfo *bt_host_hci(const char *id)
 202 {
 203     fprintf(stderr, "qemu: bluetooth passthrough not supported (yet)\n");
 204
 205     return 0;
 206 }
 207 #endif