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|
/* $FreeBSD$ */
/*-
* Copyright (c) 2008 Hans Petter Selasky. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifdef LIBUSB_GLOBAL_INCLUDE_FILE
#include LIBUSB_GLOBAL_INCLUDE_FILE
#else
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <sys/queue.h>
#endif
#include "libusb20.h"
#include "libusb20_desc.h"
#include "libusb20_int.h"
static const uint32_t libusb20_me_encode_empty[2]; /* dummy */
LIBUSB20_MAKE_STRUCT_FORMAT(LIBUSB20_DEVICE_DESC);
LIBUSB20_MAKE_STRUCT_FORMAT(LIBUSB20_ENDPOINT_DESC);
LIBUSB20_MAKE_STRUCT_FORMAT(LIBUSB20_INTERFACE_DESC);
LIBUSB20_MAKE_STRUCT_FORMAT(LIBUSB20_CONFIG_DESC);
LIBUSB20_MAKE_STRUCT_FORMAT(LIBUSB20_CONTROL_SETUP);
LIBUSB20_MAKE_STRUCT_FORMAT(LIBUSB20_SS_ENDPT_COMP_DESC);
LIBUSB20_MAKE_STRUCT_FORMAT(LIBUSB20_USB_20_DEVCAP_DESC);
LIBUSB20_MAKE_STRUCT_FORMAT(LIBUSB20_SS_USB_DEVCAP_DESC);
LIBUSB20_MAKE_STRUCT_FORMAT(LIBUSB20_BOS_DESCRIPTOR);
/*------------------------------------------------------------------------*
* libusb20_parse_config_desc
*
* Return values:
* NULL: Out of memory.
* Else: A valid config structure pointer which must be passed to "free()"
*------------------------------------------------------------------------*/
struct libusb20_config *
libusb20_parse_config_desc(const void *config_desc)
{
struct libusb20_config *lub_config;
struct libusb20_interface *lub_interface;
struct libusb20_interface *lub_alt_interface;
struct libusb20_interface *last_if;
struct libusb20_endpoint *lub_endpoint;
struct libusb20_endpoint *last_ep;
struct libusb20_me_struct pcdesc;
const uint8_t *ptr;
uint32_t size;
uint16_t niface_no_alt;
uint16_t niface;
uint16_t nendpoint;
uint16_t iface_no;
ptr = config_desc;
if (ptr[1] != LIBUSB20_DT_CONFIG) {
return (NULL); /* not config descriptor */
}
/*
* The first "bInterfaceNumber" should never have the value 0xff.
* Then it is corrupt.
*/
niface_no_alt = 0;
nendpoint = 0;
niface = 0;
iface_no = 0xFFFF;
ptr = NULL;
/* get "wTotalLength" and setup "pcdesc" */
pcdesc.ptr = LIBUSB20_ADD_BYTES(config_desc, 0);
pcdesc.len =
((const uint8_t *)config_desc)[2] |
(((const uint8_t *)config_desc)[3] << 8);
pcdesc.type = LIBUSB20_ME_IS_RAW;
/* descriptor pre-scan */
while ((ptr = libusb20_desc_foreach(&pcdesc, ptr))) {
if (ptr[1] == LIBUSB20_DT_ENDPOINT) {
nendpoint++;
} else if ((ptr[1] == LIBUSB20_DT_INTERFACE) && (ptr[0] >= 4)) {
niface++;
/* check "bInterfaceNumber" */
if (ptr[2] != iface_no) {
iface_no = ptr[2];
niface_no_alt++;
}
}
}
/* sanity checking */
if (niface >= 256) {
return (NULL); /* corrupt */
}
if (nendpoint >= 256) {
return (NULL); /* corrupt */
}
size = sizeof(*lub_config) +
(niface * sizeof(*lub_interface)) +
(nendpoint * sizeof(*lub_endpoint)) +
pcdesc.len;
lub_config = malloc(size);
if (lub_config == NULL) {
return (NULL); /* out of memory */
}
/* make sure memory is initialised */
memset(lub_config, 0, size);
lub_interface = (void *)(lub_config + 1);
lub_alt_interface = (void *)(lub_interface + niface_no_alt);
lub_endpoint = (void *)(lub_interface + niface);
/*
* Make a copy of the config descriptor, so that the caller can free
* the inital config descriptor pointer!
*/
ptr = (void *)(lub_endpoint + nendpoint);
memcpy(LIBUSB20_ADD_BYTES(ptr, 0), config_desc, pcdesc.len);
pcdesc.ptr = LIBUSB20_ADD_BYTES(ptr, 0);
config_desc = LIBUSB20_ADD_BYTES(ptr, 0);
/* init config structure */
ptr = config_desc;
LIBUSB20_INIT(LIBUSB20_CONFIG_DESC, &lub_config->desc);
if (libusb20_me_decode(ptr, ptr[0], &lub_config->desc)) {
/* ignore */
}
lub_config->num_interface = 0;
lub_config->interface = lub_interface;
lub_config->extra.ptr = LIBUSB20_ADD_BYTES(ptr, ptr[0]);
lub_config->extra.len = -ptr[0];
lub_config->extra.type = LIBUSB20_ME_IS_RAW;
/* reset states */
niface = 0;
iface_no = 0xFFFF;
ptr = NULL;
lub_interface--;
lub_endpoint--;
last_if = NULL;
last_ep = NULL;
/* descriptor pre-scan */
while ((ptr = libusb20_desc_foreach(&pcdesc, ptr))) {
if (ptr[1] == LIBUSB20_DT_ENDPOINT) {
if (last_if) {
lub_endpoint++;
last_ep = lub_endpoint;
last_if->num_endpoints++;
LIBUSB20_INIT(LIBUSB20_ENDPOINT_DESC, &last_ep->desc);
if (libusb20_me_decode(ptr, ptr[0], &last_ep->desc)) {
/* ignore */
}
last_ep->extra.ptr = LIBUSB20_ADD_BYTES(ptr, ptr[0]);
last_ep->extra.len = 0;
last_ep->extra.type = LIBUSB20_ME_IS_RAW;
} else {
lub_config->extra.len += ptr[0];
}
} else if ((ptr[1] == LIBUSB20_DT_INTERFACE) && (ptr[0] >= 4)) {
if (ptr[2] != iface_no) {
/* new interface */
iface_no = ptr[2];
lub_interface++;
lub_config->num_interface++;
last_if = lub_interface;
niface++;
} else {
/* one more alternate setting */
lub_interface->num_altsetting++;
last_if = lub_alt_interface;
lub_alt_interface++;
}
LIBUSB20_INIT(LIBUSB20_INTERFACE_DESC, &last_if->desc);
if (libusb20_me_decode(ptr, ptr[0], &last_if->desc)) {
/* ignore */
}
/*
* Sometimes USB devices have corrupt interface
* descriptors and we need to overwrite the provided
* interface number!
*/
last_if->desc.bInterfaceNumber = niface - 1;
last_if->extra.ptr = LIBUSB20_ADD_BYTES(ptr, ptr[0]);
last_if->extra.len = 0;
last_if->extra.type = LIBUSB20_ME_IS_RAW;
last_if->endpoints = lub_endpoint + 1;
last_if->altsetting = lub_alt_interface;
last_if->num_altsetting = 0;
last_if->num_endpoints = 0;
last_ep = NULL;
} else {
/* unknown descriptor */
if (last_if) {
if (last_ep) {
last_ep->extra.len += ptr[0];
} else {
last_if->extra.len += ptr[0];
}
} else {
lub_config->extra.len += ptr[0];
}
}
}
return (lub_config);
}
/*------------------------------------------------------------------------*
* libusb20_desc_foreach
*
* Safe traversal of USB descriptors.
*
* Return values:
* NULL: End of descriptors
* Else: Pointer to next descriptor
*------------------------------------------------------------------------*/
const uint8_t *
libusb20_desc_foreach(const struct libusb20_me_struct *pdesc,
const uint8_t *psubdesc)
{
const uint8_t *start;
const uint8_t *end;
const uint8_t *desc_next;
/* be NULL safe */
if (pdesc == NULL)
return (NULL);
start = (const uint8_t *)pdesc->ptr;
end = LIBUSB20_ADD_BYTES(start, pdesc->len);
/* get start of next descriptor */
if (psubdesc == NULL)
psubdesc = start;
else
psubdesc = psubdesc + psubdesc[0];
/* check that the next USB descriptor is within the range */
if ((psubdesc < start) || (psubdesc >= end))
return (NULL); /* out of range, or EOD */
/* check start of the second next USB descriptor, if any */
desc_next = psubdesc + psubdesc[0];
if ((desc_next < start) || (desc_next > end))
return (NULL); /* out of range */
/* check minimum descriptor length */
if (psubdesc[0] < 3)
return (NULL); /* too short descriptor */
return (psubdesc); /* return start of next descriptor */
}
/*------------------------------------------------------------------------*
* libusb20_me_get_1 - safety wrapper to read out one byte
*------------------------------------------------------------------------*/
uint8_t
libusb20_me_get_1(const struct libusb20_me_struct *ie, uint16_t offset)
{
if (offset < ie->len) {
return (*((uint8_t *)LIBUSB20_ADD_BYTES(ie->ptr, offset)));
}
return (0);
}
/*------------------------------------------------------------------------*
* libusb20_me_get_2 - safety wrapper to read out one word
*------------------------------------------------------------------------*/
uint16_t
libusb20_me_get_2(const struct libusb20_me_struct *ie, uint16_t offset)
{
return (libusb20_me_get_1(ie, offset) |
(libusb20_me_get_1(ie, offset + 1) << 8));
}
/*------------------------------------------------------------------------*
* libusb20_me_encode - encode a message structure
*
* Description of parameters:
* "len" - maximum length of output buffer
* "ptr" - pointer to output buffer. If NULL, no data will be written
* "pd" - source structure
*
* Return values:
* 0..65535 - Number of bytes used, limited by the "len" input parameter.
*------------------------------------------------------------------------*/
uint16_t
libusb20_me_encode(void *ptr, uint16_t len, const void *pd)
{
const uint8_t *pf; /* pointer to format data */
uint8_t *buf; /* pointer to output buffer */
uint32_t pd_offset; /* decoded structure offset */
uint16_t len_old; /* old length */
uint16_t pd_count; /* decoded element count */
uint8_t me; /* message element */
/* initialise */
len_old = len;
buf = ptr;
pd_offset = sizeof(void *);
pf = (*((struct libusb20_me_format *const *)pd))->format;
/* scan */
while (1) {
/* get information element */
me = (pf[0]) & LIBUSB20_ME_MASK;
pd_count = pf[1] | (pf[2] << 8);
pf += 3;
/* encode the message element */
switch (me) {
case LIBUSB20_ME_INT8:
while (pd_count--) {
uint8_t temp;
if (len < 1) /* overflow */
goto done;
if (buf) {
temp = *((const uint8_t *)
LIBUSB20_ADD_BYTES(pd, pd_offset));
buf[0] = temp;
buf += 1;
}
pd_offset += 1;
len -= 1;
}
break;
case LIBUSB20_ME_INT16:
pd_offset = -((-pd_offset) & ~1); /* align */
while (pd_count--) {
uint16_t temp;
if (len < 2) /* overflow */
goto done;
if (buf) {
temp = *((const uint16_t *)
LIBUSB20_ADD_BYTES(pd, pd_offset));
buf[1] = (temp >> 8) & 0xFF;
buf[0] = temp & 0xFF;
buf += 2;
}
pd_offset += 2;
len -= 2;
}
break;
case LIBUSB20_ME_INT32:
pd_offset = -((-pd_offset) & ~3); /* align */
while (pd_count--) {
uint32_t temp;
if (len < 4) /* overflow */
goto done;
if (buf) {
temp = *((const uint32_t *)
LIBUSB20_ADD_BYTES(pd, pd_offset));
buf[3] = (temp >> 24) & 0xFF;
buf[2] = (temp >> 16) & 0xFF;
buf[1] = (temp >> 8) & 0xFF;
buf[0] = temp & 0xFF;
buf += 4;
}
pd_offset += 4;
len -= 4;
}
break;
case LIBUSB20_ME_INT64:
pd_offset = -((-pd_offset) & ~7); /* align */
while (pd_count--) {
uint64_t temp;
if (len < 8) /* overflow */
goto done;
if (buf) {
temp = *((const uint64_t *)
LIBUSB20_ADD_BYTES(pd, pd_offset));
buf[7] = (temp >> 56) & 0xFF;
buf[6] = (temp >> 48) & 0xFF;
buf[5] = (temp >> 40) & 0xFF;
buf[4] = (temp >> 32) & 0xFF;
buf[3] = (temp >> 24) & 0xFF;
buf[2] = (temp >> 16) & 0xFF;
buf[1] = (temp >> 8) & 0xFF;
buf[0] = temp & 0xFF;
buf += 8;
}
pd_offset += 8;
len -= 8;
}
break;
case LIBUSB20_ME_STRUCT:
pd_offset = -((-pd_offset) &
~(LIBUSB20_ME_STRUCT_ALIGN - 1)); /* align */
while (pd_count--) {
void *src_ptr;
uint16_t src_len;
struct libusb20_me_struct *ps;
ps = LIBUSB20_ADD_BYTES(pd, pd_offset);
switch (ps->type) {
case LIBUSB20_ME_IS_RAW:
src_len = ps->len;
src_ptr = ps->ptr;
break;
case LIBUSB20_ME_IS_ENCODED:
if (ps->len == 0) {
/*
* Length is encoded
* in the data itself
* and should be
* correct:
*/
ps->len = 0xFFFF;
}
src_len = libusb20_me_get_1(pd, 0);
src_ptr = LIBUSB20_ADD_BYTES(ps->ptr, 1);
if (src_len == 0xFF) {
/* length is escaped */
src_len = libusb20_me_get_2(pd, 1);
src_ptr =
LIBUSB20_ADD_BYTES(ps->ptr, 3);
}
break;
case LIBUSB20_ME_IS_DECODED:
/* reserve 3 length bytes */
src_len = libusb20_me_encode(NULL,
0xFFFF - 3, ps->ptr);
src_ptr = NULL;
break;
default: /* empty structure */
src_len = 0;
src_ptr = NULL;
break;
}
if (src_len > 0xFE) {
if (src_len > (0xFFFF - 3))
/* overflow */
goto done;
if (len < (src_len + 3))
/* overflow */
goto done;
if (buf) {
buf[0] = 0xFF;
buf[1] = (src_len & 0xFF);
buf[2] = (src_len >> 8) & 0xFF;
buf += 3;
}
len -= (src_len + 3);
} else {
if (len < (src_len + 1))
/* overflow */
goto done;
if (buf) {
buf[0] = (src_len & 0xFF);
buf += 1;
}
len -= (src_len + 1);
}
/* check for buffer and non-zero length */
if (buf && src_len) {
if (ps->type == LIBUSB20_ME_IS_DECODED) {
/*
* Repeat encode
* procedure - we have
* room for the
* complete structure:
*/
(void) libusb20_me_encode(buf,
0xFFFF - 3, ps->ptr);
} else {
bcopy(src_ptr, buf, src_len);
}
buf += src_len;
}
pd_offset += sizeof(struct libusb20_me_struct);
}
break;
default:
goto done;
}
}
done:
return (len_old - len);
}
/*------------------------------------------------------------------------*
* libusb20_me_decode - decode a message into a decoded structure
*
* Description of parameters:
* "ptr" - message pointer
* "len" - message length
* "pd" - pointer to decoded structure
*
* Returns:
* "0..65535" - number of bytes decoded, limited by "len"
*------------------------------------------------------------------------*/
uint16_t
libusb20_me_decode(const void *ptr, uint16_t len, void *pd)
{
const uint8_t *pf; /* pointer to format data */
const uint8_t *buf; /* pointer to input buffer */
uint32_t pd_offset; /* decoded structure offset */
uint16_t len_old; /* old length */
uint16_t pd_count; /* decoded element count */
uint8_t me; /* message element */
/* initialise */
len_old = len;
buf = ptr;
pd_offset = sizeof(void *);
pf = (*((struct libusb20_me_format **)pd))->format;
/* scan */
while (1) {
/* get information element */
me = (pf[0]) & LIBUSB20_ME_MASK;
pd_count = pf[1] | (pf[2] << 8);
pf += 3;
/* decode the message element by type */
switch (me) {
case LIBUSB20_ME_INT8:
while (pd_count--) {
uint8_t temp;
if (len < 1) {
len = 0;
temp = 0;
} else {
len -= 1;
temp = buf[0];
buf++;
}
*((uint8_t *)LIBUSB20_ADD_BYTES(pd,
pd_offset)) = temp;
pd_offset += 1;
}
break;
case LIBUSB20_ME_INT16:
pd_offset = -((-pd_offset) & ~1); /* align */
while (pd_count--) {
uint16_t temp;
if (len < 2) {
len = 0;
temp = 0;
} else {
len -= 2;
temp = buf[1] << 8;
temp |= buf[0];
buf += 2;
}
*((uint16_t *)LIBUSB20_ADD_BYTES(pd,
pd_offset)) = temp;
pd_offset += 2;
}
break;
case LIBUSB20_ME_INT32:
pd_offset = -((-pd_offset) & ~3); /* align */
while (pd_count--) {
uint32_t temp;
if (len < 4) {
len = 0;
temp = 0;
} else {
len -= 4;
temp = buf[3] << 24;
temp |= buf[2] << 16;
temp |= buf[1] << 8;
temp |= buf[0];
buf += 4;
}
*((uint32_t *)LIBUSB20_ADD_BYTES(pd,
pd_offset)) = temp;
pd_offset += 4;
}
break;
case LIBUSB20_ME_INT64:
pd_offset = -((-pd_offset) & ~7); /* align */
while (pd_count--) {
uint64_t temp;
if (len < 8) {
len = 0;
temp = 0;
} else {
len -= 8;
temp = ((uint64_t)buf[7]) << 56;
temp |= ((uint64_t)buf[6]) << 48;
temp |= ((uint64_t)buf[5]) << 40;
temp |= ((uint64_t)buf[4]) << 32;
temp |= buf[3] << 24;
temp |= buf[2] << 16;
temp |= buf[1] << 8;
temp |= buf[0];
buf += 8;
}
*((uint64_t *)LIBUSB20_ADD_BYTES(pd,
pd_offset)) = temp;
pd_offset += 8;
}
break;
case LIBUSB20_ME_STRUCT:
pd_offset = -((-pd_offset) &
~(LIBUSB20_ME_STRUCT_ALIGN - 1)); /* align */
while (pd_count--) {
uint16_t temp;
struct libusb20_me_struct *ps;
ps = LIBUSB20_ADD_BYTES(pd, pd_offset);
if (ps->type == LIBUSB20_ME_IS_ENCODED) {
/*
* Pre-store a de-constified
* pointer to the raw
* structure:
*/
ps->ptr = LIBUSB20_ADD_BYTES(buf, 0);
/*
* Get the correct number of
* length bytes:
*/
if (len != 0) {
if (buf[0] == 0xFF) {
ps->len = 3;
} else {
ps->len = 1;
}
} else {
ps->len = 0;
}
}
/* get the structure length */
if (len != 0) {
if (buf[0] == 0xFF) {
if (len < 3) {
len = 0;
temp = 0;
} else {
len -= 3;
temp = buf[1] |
(buf[2] << 8);
buf += 3;
}
} else {
len -= 1;
temp = buf[0];
buf += 1;
}
} else {
len = 0;
temp = 0;
}
/* check for invalid length */
if (temp > len) {
len = 0;
temp = 0;
}
/* check wanted structure type */
switch (ps->type) {
case LIBUSB20_ME_IS_ENCODED:
/* check for zero length */
if (temp == 0) {
/*
* The pointer must
* be valid:
*/
ps->ptr = LIBUSB20_ADD_BYTES(
libusb20_me_encode_empty, 0);
ps->len = 1;
} else {
ps->len += temp;
}
break;
case LIBUSB20_ME_IS_RAW:
/* update length and pointer */
ps->len = temp;
ps->ptr = LIBUSB20_ADD_BYTES(buf, 0);
break;
case LIBUSB20_ME_IS_EMPTY:
case LIBUSB20_ME_IS_DECODED:
/* check for non-zero length */
if (temp != 0) {
/* update type */
ps->type = LIBUSB20_ME_IS_DECODED;
ps->len = 0;
/*
* Recursivly decode
* the next structure
*/
(void) libusb20_me_decode(buf,
temp, ps->ptr);
} else {
/* update type */
ps->type = LIBUSB20_ME_IS_EMPTY;
ps->len = 0;
}
break;
default:
/*
* nothing to do - should
* not happen
*/
ps->ptr = NULL;
ps->len = 0;
break;
}
buf += temp;
len -= temp;
pd_offset += sizeof(struct libusb20_me_struct);
}
break;
default:
goto done;
}
}
done:
return (len_old - len);
}
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