TestMsUsb.c

#include <winpr/crt.h>
#include <winpr/stream.h>
 
#include <msusb.h>
 
/* One MSUSB interface descriptor with NumberOfPipes == 0 (12 bytes) followed by
 * the 6 byte configuration descriptor trailer that msusb_msconfig_read reads. */
static const BYTE config_one_iface[] = {
  /* interface[0] */
  0x12, 0x00,             /* Length */
  0x00, 0x00,             /* NumberOfPipesExpected */
  0x00,                   /* InterfaceNumber */
  0x00,                   /* AlternateSetting */
  0x00, 0x00,             /* padding */
  0x00, 0x00, 0x00, 0x00, /* NumberOfPipes = 0 */
  /* configuration descriptor trailer */
  0x09,       /* lenConfiguration */
  0x02,       /* typeConfiguration */
  0xef, 0xbe, /* wTotalLength = 0xBEEF */
  0x00,       /* padding */
  0x42        /* bConfigurationValue */
};
 
static int test_full_config(void)
{
  wStream sbuffer = { 0 };
  wStream* s = Stream_StaticConstInit(&sbuffer, config_one_iface, sizeof(config_one_iface));
 
  MSUSB_CONFIG_DESCRIPTOR* cfg = msusb_msconfig_read(s, 1);
  if (!cfg)
  {
    (void)fprintf(stderr, "msusb_msconfig_read rejected a complete descriptor\n");
    return -1;
  }
 
  int rc = 0;
  if ((cfg->wTotalLength != 0xBEEF) || (cfg->bConfigurationValue != 0x42) ||
      (cfg->NumInterfaces != 1))
  {
    (void)fprintf(stderr, "msusb_msconfig_read parsed wrong values\n");
    rc = -1;
  }
  msusb_msconfig_free(cfg);
  return rc;
}
 
/* The descriptor data ends right after the interface list: the 6 byte
 * configuration trailer is missing. The reader must not walk past the end of
 * the received data. */
static int test_truncated_trailer(void)
{
  wStream sbuffer = { 0 };
  wStream* s = Stream_StaticConstInit(&sbuffer, config_one_iface, 12);
 
  MSUSB_CONFIG_DESCRIPTOR* cfg = msusb_msconfig_read(s, 1);
  if (cfg)
  {
    (void)fprintf(stderr, "msusb_msconfig_read accepted a truncated trailer\n");
    msusb_msconfig_free(cfg);
    return -1;
  }
  return 0;
}
 
/* Capacity larger than the sealed length must not let the reader consume the
 * unused tail of the (recycled) buffer. */
static int test_capacity_exceeds_length(void)
{
  BYTE buffer[64] = { 0 };
  CopyMemory(buffer, config_one_iface, sizeof(config_one_iface));
 
  wStream sbuffer = { 0 };
  wStream* s = Stream_StaticInit(&sbuffer, buffer, sizeof(buffer));
  if (!Stream_SetLength(s, 12))
    return -1;
 
  MSUSB_CONFIG_DESCRIPTOR* cfg = msusb_msconfig_read(s, 1);
  if (cfg)
  {
    (void)fprintf(stderr, "msusb_msconfig_read read past the sealed length\n");
    msusb_msconfig_free(cfg);
    return -1;
  }
  return 0;
}
 
/* msusb_msinterface_read claims NumberOfPipes pipes whose data is not present. */
static int test_interface_truncated_pipes(void)
{
  const BYTE iface[] = {
    0x10, 0x00,            /* Length */
    0x01, 0x00,            /* NumberOfPipesExpected */
    0x00,                  /* InterfaceNumber */
    0x00,                  /* AlternateSetting */
    0x00, 0x00,            /* padding */
    0x04, 0x00, 0x00, 0x00 /* NumberOfPipes = 4, but no pipe data follows */
  };
  wStream sbuffer = { 0 };
  wStream* s = Stream_StaticConstInit(&sbuffer, iface, sizeof(iface));
 
  MSUSB_INTERFACE_DESCRIPTOR* desc = msusb_msinterface_read(s);
  if (desc)
  {
    (void)fprintf(stderr, "msusb_msinterface_read accepted missing pipe data\n");
    msusb_msinterface_free(desc);
    return -1;
  }
  return 0;
}
 
int TestMsUsb(int argc, char* argv[])
{
  WINPR_UNUSED(argc);
  WINPR_UNUSED(argv);
 
  if (test_full_config() != 0)
    return -1;
  if (test_truncated_trailer() != 0)
    return -1;
  if (test_capacity_exceeds_length() != 0)
    return -1;
  if (test_interface_truncated_pipes() != 0)
    return -1;
  return 0;
}