/* guid-utils.c

 * GUID handling

 *

 * Wireshark - Network traffic analyzer

 * By Gerald Combs <gerald@wireshark.org>

 *

 * Copyright 1998 Gerald Combs

 *

 * SPDX-License-Identifier: GPL-2.0-or-later

 */

#include "config.h"

#include <string.h>

#include <glib.h>

#include <epan/epan.h>

#include <wsutil/unicode-utils.h>

#include <epan/wmem_scopes.h>

#include "guid-utils.h"

#ifdef _WIN32

#include <tchar.h>

#include <windows.h>

#include <strsafe.h>

#endif

static wmem_tree_t *guid_to_name_tree;

#ifdef _WIN32

/* try to resolve an DCE/RPC interface name to its name using the Windows registry entries */

/* XXX - might be better to fill all interfaces into our database at startup instead of searching each time */

static int

ResolveWin32UUID(e_guid_t if_id, char *uuid_name, int uuid_name_max_len)

{

  TCHAR *reg_uuid_name;

  HKEY hKey = NULL;

  DWORD uuid_max_size = MAX_PATH;

  TCHAR *reg_uuid_str;

  reg_uuid_name=wmem_alloc(NULL, (MAX_PATH*sizeof(TCHAR))+1);

  reg_uuid_str=wmem_alloc(NULL, (MAX_PATH*sizeof(TCHAR))+1);

  if(uuid_name_max_len < 2){

    return 0;

  }

  reg_uuid_name[0] = '\0';

  StringCchPrintf(reg_uuid_str, MAX_PATH, _T("SOFTWARE\\Classes\\Interface\\{%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x}"),

      if_id.data1, if_id.data2, if_id.data3,

      if_id.data4[0], if_id.data4[1],

      if_id.data4[2], if_id.data4[3],

      if_id.data4[4], if_id.data4[5],

      if_id.data4[6], if_id.data4[7]);

  if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, reg_uuid_str, 0, KEY_QUERY_VALUE, &hKey) == ERROR_SUCCESS) {

    if (RegQueryValueEx(hKey, NULL, NULL, NULL, (LPBYTE)reg_uuid_name, &uuid_max_size) == ERROR_SUCCESS && uuid_max_size <= MAX_PATH) {

      snprintf(uuid_name, uuid_name_max_len, "%s", utf_16to8(reg_uuid_name));

      RegCloseKey(hKey);

      wmem_free(NULL, reg_uuid_name);

      wmem_free(NULL, reg_uuid_str);

      return (int) strlen(uuid_name);

    }

    RegCloseKey(hKey);

  }

  wmem_free(NULL, reg_uuid_name);

  wmem_free(NULL, reg_uuid_str);

  return 0; /* we didn't find anything anyhow. Please don't use the string! */

}

#endif

/* store a guid to name mapping */

void

guids_add_guid(const e_guid_t *guid, const char *name)

{

  wmem_tree_key_t guidkey[2];

  uint32_t g[4];

  g[0]=guid->data1;

  g[1]=guid->data2;

  g[1]<<=16;

  g[1]|=guid->data3;

  g[2]=guid->data4[0];

  g[2]<<=8;

  g[2]|=guid->data4[1];

  g[2]<<=8;

  g[2]|=guid->data4[2];

  g[2]<<=8;

  g[2]|=guid->data4[3];

  g[3]=guid->data4[4];

  g[3]<<=8;

  g[3]|=guid->data4[5];

  g[3]<<=8;

  g[3]|=guid->data4[6];

  g[3]<<=8;

  g[3]|=guid->data4[7];

  guidkey[0].key=g;

  guidkey[0].length=4;

  guidkey[1].length=0;

  wmem_tree_insert32_array(guid_to_name_tree, &guidkey[0], (char *) name);

}

/* remove a guid to name mapping */

void

guids_delete_guid(const e_guid_t *guid)

{

  wmem_tree_key_t guidkey[2];

  uint32_t g[4];

  g[0] = guid->data1;

  g[1] = guid->data2;

  g[1] <<= 16;

  g[1] |= guid->data3;

  g[2] = guid->data4[0];

  g[2] <<= 8;

  g[2] |= guid->data4[1];

  g[2] <<= 8;

  g[2] |= guid->data4[2];

  g[2] <<= 8;

  g[2] |= guid->data4[3];

  g[3] = guid->data4[4];

  g[3] <<= 8;

  g[3] |= guid->data4[5];

  g[3] <<= 8;

  g[3] |= guid->data4[6];

  g[3] <<= 8;

  g[3] |= guid->data4[7];

  guidkey[0].key = g;

  guidkey[0].length = 4;

  guidkey[1].length = 0;

  void *data = wmem_tree_lookup32_array(guid_to_name_tree, &guidkey[0]);

  if (data != NULL) {

    // This will "remove" the entry by setting its data to NULL

    wmem_tree_insert32_array(guid_to_name_tree, &guidkey[0], NULL);

  }

}

/* retrieve the registered name for this GUID; uses the scope for the fallback case only */

const char *

guids_get_guid_name(const e_guid_t *guid, wmem_allocator_t *scope _U_)

{

  wmem_tree_key_t guidkey[2];

  uint32_t g[4];

  char *name;

#ifdef _WIN32

  static char *uuid_name;

#endif

  g[0]=guid->data1;

  g[1]=guid->data2;

  g[1]<<=16;

  g[1]|=guid->data3;

  g[2]=guid->data4[0];

  g[2]<<=8;

  g[2]|=guid->data4[1];

  g[2]<<=8;

  g[2]|=guid->data4[2];

  g[2]<<=8;

  g[2]|=guid->data4[3];

  g[3]=guid->data4[4];

  g[3]<<=8;

  g[3]|=guid->data4[5];

  g[3]<<=8;

  g[3]|=guid->data4[6];

  g[3]<<=8;

  g[3]|=guid->data4[7];

  guidkey[0].key=g;

  guidkey[0].length=4;

  guidkey[1].length=0;

  if((name = (char *)wmem_tree_lookup32_array(guid_to_name_tree, &guidkey[0]))){

    return name;

  }

#ifdef _WIN32

  /* try to resolve the mapping from the Windows registry */

  /* XXX - prefill the resolving database with all the Windows registry entries once at init only (instead of searching each time)? */

  uuid_name=wmem_alloc(scope, 128);

  if(ResolveWin32UUID(*guid, uuid_name, 128)) {

    return uuid_name;

  }

#endif

  return NULL;

}

void

guids_init(void)

{

  guid_to_name_tree=wmem_tree_new(wmem_epan_scope());

  /* XXX here is a good place to read a config file with wellknown guids */

}

/* Tries to match a guid against its name.

   Returns the associated string ptr on a match.

   Formats uuid number and returns the resulting string via wmem scope, if name is unknown.

   (derived from val_to_str) */

const char *

guids_resolve_guid_to_str(const e_guid_t *guid, wmem_allocator_t *scope)

{

  const char *name;

  name=guids_get_guid_name(guid, scope);

  if(name){

    return name;

  }

  return wmem_strdup_printf(scope, "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",

        guid->data1, guid->data2, guid->data3,

        guid->data4[0], guid->data4[1],

        guid->data4[2], guid->data4[3],

        guid->data4[4], guid->data4[5],

        guid->data4[6], guid->data4[7]);

}

int guid_cmp(const e_guid_t *g1, const e_guid_t *g2)

{

  if (g1->data1 != g2->data1) {

    return (g1->data1 < g2->data1) ? -1 : 1;

  }

  if (g1->data2 != g2->data2) {

    return (g1->data2 < g2->data2) ? -1 : 1;

  }

  if (g1->data3 != g2->data3) {

    return (g1->data3 < g2->data3) ? -1 : 1;

  }

  return memcmp(&g1->data4[0], &g2->data4[0], 8);

}

unsigned guid_hash(const e_guid_t *guid)

{

  return g_int64_hash((const int64_t *)guid);

}

/*

 * Editor modelines  -  https://www.wireshark.org/tools/modelines.html

 *

 * Local variables:

 * c-basic-offset: 8

 * tab-width: 8

 * indent-tabs-mode: t

 * End:

 *

 * vi: set shiftwidth=8 tabstop=8 noexpandtab:

 * :indentSize=8:tabSize=8:noTabs=false:

 */