qemu/hw/usb.c
Hans de Goede 19f3322379 usb: control buffer fixes
Windows allows control transfers to pass up to 4k of data, so raise our
control buffer size to 4k. For control out transfers the usb core code copies
the control request data to a buffer before calling the device's handle_control
callback. Add a check for overflowing the buffer before copying the data.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2011-05-04 12:25:52 +02:00

268 lines
7.1 KiB
C

/*
* QEMU USB emulation
*
* Copyright (c) 2005 Fabrice Bellard
*
* 2008 Generic packet handler rewrite by Max Krasnyansky
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu-common.h"
#include "usb.h"
void usb_attach(USBPort *port, USBDevice *dev)
{
if (dev != NULL) {
/* attach */
if (port->dev) {
usb_attach(port, NULL);
}
dev->port = port;
port->dev = dev;
port->ops->attach(port);
usb_send_msg(dev, USB_MSG_ATTACH);
} else {
/* detach */
dev = port->dev;
port->ops->detach(port);
if (dev) {
usb_send_msg(dev, USB_MSG_DETACH);
dev->port = NULL;
port->dev = NULL;
}
}
}
void usb_wakeup(USBDevice *dev)
{
if (dev->remote_wakeup && dev->port && dev->port->ops->wakeup) {
dev->port->ops->wakeup(dev);
}
}
/**********************/
/* generic USB device helpers (you are not forced to use them when
writing your USB device driver, but they help handling the
protocol)
*/
#define SETUP_STATE_IDLE 0
#define SETUP_STATE_DATA 1
#define SETUP_STATE_ACK 2
static int do_token_setup(USBDevice *s, USBPacket *p)
{
int request, value, index;
int ret = 0;
if (p->len != 8)
return USB_RET_STALL;
memcpy(s->setup_buf, p->data, 8);
s->setup_len = (s->setup_buf[7] << 8) | s->setup_buf[6];
s->setup_index = 0;
request = (s->setup_buf[0] << 8) | s->setup_buf[1];
value = (s->setup_buf[3] << 8) | s->setup_buf[2];
index = (s->setup_buf[5] << 8) | s->setup_buf[4];
if (s->setup_buf[0] & USB_DIR_IN) {
ret = s->info->handle_control(s, request, value, index,
s->setup_len, s->data_buf);
if (ret < 0)
return ret;
if (ret < s->setup_len)
s->setup_len = ret;
s->setup_state = SETUP_STATE_DATA;
} else {
if (s->setup_len > sizeof(s->data_buf)) {
fprintf(stderr,
"usb_generic_handle_packet: ctrl buffer too small (%d > %zu)\n",
s->setup_len, sizeof(s->data_buf));
return USB_RET_STALL;
}
if (s->setup_len == 0)
s->setup_state = SETUP_STATE_ACK;
else
s->setup_state = SETUP_STATE_DATA;
}
return ret;
}
static int do_token_in(USBDevice *s, USBPacket *p)
{
int request, value, index;
int ret = 0;
if (p->devep != 0)
return s->info->handle_data(s, p);
request = (s->setup_buf[0] << 8) | s->setup_buf[1];
value = (s->setup_buf[3] << 8) | s->setup_buf[2];
index = (s->setup_buf[5] << 8) | s->setup_buf[4];
switch(s->setup_state) {
case SETUP_STATE_ACK:
if (!(s->setup_buf[0] & USB_DIR_IN)) {
s->setup_state = SETUP_STATE_IDLE;
ret = s->info->handle_control(s, request, value, index,
s->setup_len, s->data_buf);
if (ret > 0)
return 0;
return ret;
}
/* return 0 byte */
return 0;
case SETUP_STATE_DATA:
if (s->setup_buf[0] & USB_DIR_IN) {
int len = s->setup_len - s->setup_index;
if (len > p->len)
len = p->len;
memcpy(p->data, s->data_buf + s->setup_index, len);
s->setup_index += len;
if (s->setup_index >= s->setup_len)
s->setup_state = SETUP_STATE_ACK;
return len;
}
s->setup_state = SETUP_STATE_IDLE;
return USB_RET_STALL;
default:
return USB_RET_STALL;
}
}
static int do_token_out(USBDevice *s, USBPacket *p)
{
if (p->devep != 0)
return s->info->handle_data(s, p);
switch(s->setup_state) {
case SETUP_STATE_ACK:
if (s->setup_buf[0] & USB_DIR_IN) {
s->setup_state = SETUP_STATE_IDLE;
/* transfer OK */
} else {
/* ignore additional output */
}
return 0;
case SETUP_STATE_DATA:
if (!(s->setup_buf[0] & USB_DIR_IN)) {
int len = s->setup_len - s->setup_index;
if (len > p->len)
len = p->len;
memcpy(s->data_buf + s->setup_index, p->data, len);
s->setup_index += len;
if (s->setup_index >= s->setup_len)
s->setup_state = SETUP_STATE_ACK;
return len;
}
s->setup_state = SETUP_STATE_IDLE;
return USB_RET_STALL;
default:
return USB_RET_STALL;
}
}
/*
* Generic packet handler.
* Called by the HC (host controller).
*
* Returns length of the transaction or one of the USB_RET_XXX codes.
*/
int usb_generic_handle_packet(USBDevice *s, USBPacket *p)
{
switch(p->pid) {
case USB_MSG_ATTACH:
s->state = USB_STATE_ATTACHED;
if (s->info->handle_attach) {
s->info->handle_attach(s);
}
return 0;
case USB_MSG_DETACH:
s->state = USB_STATE_NOTATTACHED;
return 0;
case USB_MSG_RESET:
s->remote_wakeup = 0;
s->addr = 0;
s->state = USB_STATE_DEFAULT;
if (s->info->handle_reset) {
s->info->handle_reset(s);
}
return 0;
}
/* Rest of the PIDs must match our address */
if (s->state < USB_STATE_DEFAULT || p->devaddr != s->addr)
return USB_RET_NODEV;
switch (p->pid) {
case USB_TOKEN_SETUP:
return do_token_setup(s, p);
case USB_TOKEN_IN:
return do_token_in(s, p);
case USB_TOKEN_OUT:
return do_token_out(s, p);
default:
return USB_RET_STALL;
}
}
/* XXX: fix overflow */
int set_usb_string(uint8_t *buf, const char *str)
{
int len, i;
uint8_t *q;
q = buf;
len = strlen(str);
*q++ = 2 * len + 2;
*q++ = 3;
for(i = 0; i < len; i++) {
*q++ = str[i];
*q++ = 0;
}
return q - buf;
}
/* Send an internal message to a USB device. */
void usb_send_msg(USBDevice *dev, int msg)
{
USBPacket p;
memset(&p, 0, sizeof(p));
p.pid = msg;
dev->info->handle_packet(dev, &p);
/* This _must_ be synchronous */
}