epan/guid-utils.c

   1 /* guid-utils.c
   2  * GUID handling
   3  *
   4  * Wireshark - Network traffic analyzer
   5  * By Gerald Combs <gerald@wireshark.org>
   6  *
   7  * Copyright 1998 Gerald Combs
   8  *
   9  * SPDX-License-Identifier: GPL-2.0-or-later
  10  */
  11
  12 #include "config.h"
  13
  14 #include <string.h>
  15
  16 #include <glib.h>
  17 #include <epan/epan.h>
  18 #include <wsutil/unicode-utils.h>
  19 #include <epan/wmem_scopes.h>
  20 #include "guid-utils.h"
  21
  22 #ifdef _WIN32
  23 #include <tchar.h>
  24 #include <windows.h>
  25 #include <strsafe.h>
  26 #endif
  27
  28 static wmem_tree_t *guid_to_name_tree;
  29
  30
  31 #ifdef _WIN32
  32 /* try to resolve an DCE/RPC interface name to its name using the Windows registry entries */
  33 /* XXX - might be better to fill all interfaces into our database at startup instead of searching each time */
  34 static int
  35 ResolveWin32UUID(e_guid_t if_id, char *uuid_name, int uuid_name_max_len)
  36 {
  37         TCHAR *reg_uuid_name;
  38         HKEY hKey = NULL;
  39         DWORD uuid_max_size = MAX_PATH;
  40         TCHAR *reg_uuid_str;
  41
  42         reg_uuid_name=wmem_alloc(NULL, (MAX_PATH*sizeof(TCHAR))+1);
  43         reg_uuid_str=wmem_alloc(NULL, (MAX_PATH*sizeof(TCHAR))+1);
  44
  45         if(uuid_name_max_len < 2){
  46                 return 0;
  47         }
  48         reg_uuid_name[0] = '\0';
  49         StringCchPrintf(reg_uuid_str, MAX_PATH, _T("SOFTWARE\\Classes\\Interface\\{%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x}"),
  50                         if_id.data1, if_id.data2, if_id.data3,
  51                         if_id.data4[0], if_id.data4[1],
  52                         if_id.data4[2], if_id.data4[3],
  53                         if_id.data4[4], if_id.data4[5],
  54                         if_id.data4[6], if_id.data4[7]);
  55         if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, reg_uuid_str, 0, KEY_QUERY_VALUE, &hKey) == ERROR_SUCCESS) {
  56                 if (RegQueryValueEx(hKey, NULL, NULL, NULL, (LPBYTE)reg_uuid_name, &uuid_max_size) == ERROR_SUCCESS && uuid_max_size <= MAX_PATH) {
  57                         snprintf(uuid_name, uuid_name_max_len, "%s", utf_16to8(reg_uuid_name));
  58                         RegCloseKey(hKey);
  59                         wmem_free(NULL, reg_uuid_name);
  60                         wmem_free(NULL, reg_uuid_str);
  61                         return (int) strlen(uuid_name);
  62                 }
  63                 RegCloseKey(hKey);
  64         }
  65         wmem_free(NULL, reg_uuid_name);
  66         wmem_free(NULL, reg_uuid_str);
  67         return 0; /* we didn't find anything anyhow. Please don't use the string! */
  68
  69 }
  70 #endif
  71
  72
  73 /* store a guid to name mapping */
  74 void
  75 guids_add_guid(const e_guid_t *guid, const char *name)
  76 {
  77         wmem_tree_key_t guidkey[2];
  78         uint32_t g[4];
  79
  80         g[0]=guid->data1;
  81
  82         g[1]=guid->data2;
  83         g[1]<<=16;
  84         g[1]|=guid->data3;
  85
  86         g[2]=guid->data4[0];
  87         g[2]<<=8;
  88         g[2]|=guid->data4[1];
  89         g[2]<<=8;
  90         g[2]|=guid->data4[2];
  91         g[2]<<=8;
  92         g[2]|=guid->data4[3];
  93
  94         g[3]=guid->data4[4];
  95         g[3]<<=8;
  96         g[3]|=guid->data4[5];
  97         g[3]<<=8;
  98         g[3]|=guid->data4[6];
  99         g[3]<<=8;
 100         g[3]|=guid->data4[7];
 101
 102         guidkey[0].key=g;
 103         guidkey[0].length=4;
 104         guidkey[1].length=0;
 105
 106         wmem_tree_insert32_array(guid_to_name_tree, &guidkey[0], (char *) name);
 107 }
 108
 109 /* remove a guid to name mapping */
 110 void
 111 guids_delete_guid(const e_guid_t *guid)
 112 {
 113         wmem_tree_key_t guidkey[2];
 114         uint32_t g[4];
 115
 116         g[0] = guid->data1;
 117
 118         g[1] = guid->data2;
 119         g[1] <<= 16;
 120         g[1] |= guid->data3;
 121
 122         g[2] = guid->data4[0];
 123         g[2] <<= 8;
 124         g[2] |= guid->data4[1];
 125         g[2] <<= 8;
 126         g[2] |= guid->data4[2];
 127         g[2] <<= 8;
 128         g[2] |= guid->data4[3];
 129
 130         g[3] = guid->data4[4];
 131         g[3] <<= 8;
 132         g[3] |= guid->data4[5];
 133         g[3] <<= 8;
 134         g[3] |= guid->data4[6];
 135         g[3] <<= 8;
 136         g[3] |= guid->data4[7];
 137
 138         guidkey[0].key = g;
 139         guidkey[0].length = 4;
 140         guidkey[1].length = 0;
 141
 142         void *data = wmem_tree_lookup32_array(guid_to_name_tree, &guidkey[0]);
 143
 144         if (data != NULL) {
 145                 // This will "remove" the entry by setting its data to NULL
 146                 wmem_tree_insert32_array(guid_to_name_tree, &guidkey[0], NULL);
 147         }
 148
 149 }
 150
 151 /* retrieve the registered name for this GUID; uses the scope for the fallback case only */
 152 const char *
 153 guids_get_guid_name(const e_guid_t *guid, wmem_allocator_t *scope _U_)
 154 {
 155         wmem_tree_key_t guidkey[2];
 156         uint32_t g[4];
 157         char *name;
 158 #ifdef _WIN32
 159         static char *uuid_name;
 160 #endif
 161
 162         g[0]=guid->data1;
 163
 164         g[1]=guid->data2;
 165         g[1]<<=16;
 166         g[1]|=guid->data3;
 167
 168         g[2]=guid->data4[0];
 169         g[2]<<=8;
 170         g[2]|=guid->data4[1];
 171         g[2]<<=8;
 172         g[2]|=guid->data4[2];
 173         g[2]<<=8;
 174         g[2]|=guid->data4[3];
 175
 176         g[3]=guid->data4[4];
 177         g[3]<<=8;
 178         g[3]|=guid->data4[5];
 179         g[3]<<=8;
 180         g[3]|=guid->data4[6];
 181         g[3]<<=8;
 182         g[3]|=guid->data4[7];
 183
 184         guidkey[0].key=g;
 185         guidkey[0].length=4;
 186         guidkey[1].length=0;
 187
 188         if((name = (char *)wmem_tree_lookup32_array(guid_to_name_tree, &guidkey[0]))){
 189                 return name;
 190         }
 191
 192 #ifdef _WIN32
 193         /* try to resolve the mapping from the Windows registry */
 194         /* XXX - prefill the resolving database with all the Windows registry entries once at init only (instead of searching each time)? */
 195         uuid_name=wmem_alloc(scope, 128);
 196         if(ResolveWin32UUID(*guid, uuid_name, 128)) {
 197                 return uuid_name;
 198         }
 199 #endif
 200
 201         return NULL;
 202 }
 203
 204
 205 void
 206 guids_init(void)
 207 {
 208         guid_to_name_tree=wmem_tree_new(wmem_epan_scope());
 209         /* XXX here is a good place to read a config file with wellknown guids */
 210 }
 211
 212
 213 /* Tries to match a guid against its name.
 214    Returns the associated string ptr on a match.
 215    Formats uuid number and returns the resulting string via wmem scope, if name is unknown.
 216    (derived from val_to_str) */
 217 const char *
 218 guids_resolve_guid_to_str(const e_guid_t *guid, wmem_allocator_t *scope)
 219 {
 220         const char *name;
 221
 222         name=guids_get_guid_name(guid, scope);
 223         if(name){
 224                 return name;
 225         }
 226
 227         return wmem_strdup_printf(scope, "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
 228                                 guid->data1, guid->data2, guid->data3,
 229                                 guid->data4[0], guid->data4[1],
 230                                 guid->data4[2], guid->data4[3],
 231                                 guid->data4[4], guid->data4[5],
 232                                 guid->data4[6], guid->data4[7]);
 233 }
 234
 235 int guid_cmp(const e_guid_t *g1, const e_guid_t *g2)
 236 {
 237         if (g1->data1 != g2->data1) {
 238                 return (g1->data1 < g2->data1) ? -1 : 1;
 239         }
 240
 241         if (g1->data2 != g2->data2) {
 242                 return (g1->data2 < g2->data2) ? -1 : 1;
 243         }
 244
 245         if (g1->data3 != g2->data3) {
 246                 return (g1->data3 < g2->data3) ? -1 : 1;
 247         }
 248
 249         return memcmp(&g1->data4[0], &g2->data4[0], 8);
 250 }
 251
 252 unsigned guid_hash(const e_guid_t *guid)
 253 {
 254         return g_int64_hash((const int64_t *)guid);
 255 }
 256
 257 /*
 258  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 259  *
 260  * Local variables:
 261  * c-basic-offset: 8
 262  * tab-width: 8
 263  * indent-tabs-mode: t
 264  * End:
 265  *
 266  * vi: set shiftwidth=8 tabstop=8 noexpandtab:
 267  * :indentSize=8:tabSize=8:noTabs=false:
 268  */