programs/svchost/svchost.c

   1 /*
   2  * Implementation of svchost.exe
   3  *
   4  * Copyright 2007 Google (Roy Shea)
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 /* Usage:
  22  * Starting a service group:
  23  *
  24  *      svchost /k service_group_name
  25  */
  26
  27 #include <stdarg.h>
  28
  29 #include "windef.h"
  30 #include "winbase.h"
  31 #include "winreg.h"
  32 #include "winsvc.h"
  33 #include "wine/debug.h"
  34
  35 WINE_DEFAULT_DEBUG_CHANNEL(svchost);
  36
  37 static const WCHAR service_reg_path[] = L"System\\CurrentControlSet\\Services";
  38 static const WCHAR svchost_path[] = L"Software\\Microsoft\\Windows NT\\CurrentVersion\\Svchost";
  39
  40 /* Allocate and initialize a WSTR containing the queried value */
  41 static LPWSTR GetRegValue(HKEY service_key, const WCHAR *value_name)
  42 {
  43     DWORD type;
  44     DWORD reg_size;
  45     DWORD size;
  46     LONG ret;
  47     LPWSTR value;
  48
  49     WINE_TRACE("\n");
  50
  51     ret = RegQueryValueExW(service_key, value_name, NULL, &type, NULL, &reg_size);
  52     if (ret != ERROR_SUCCESS)
  53     {
  54         return NULL;
  55     }
  56
  57     /* Add space for potentially missing NULL terminators in initial alloc.
  58      * The worst case REG_MULTI_SZ requires two NULL terminators. */
  59     size = reg_size + (2 * sizeof(WCHAR));
  60     value = HeapAlloc(GetProcessHeap(), 0, size);
  61
  62     ret = RegQueryValueExW(service_key, value_name, NULL, &type,
  63             (LPBYTE)value, &reg_size);
  64     if (ret != ERROR_SUCCESS)
  65     {
  66         HeapFree(GetProcessHeap(), 0, value);
  67         return NULL;
  68     }
  69
  70     /* Explicitly NULL terminate the result */
  71     value[size / sizeof(WCHAR) - 1] = '\0';
  72     value[size / sizeof(WCHAR) - 2] = '\0';
  73
  74     return value;
  75 }
  76
  77 /* Allocate and initialize a WSTR containing the expanded string */
  78 static LPWSTR ExpandEnv(LPWSTR string)
  79 {
  80     DWORD size;
  81     LPWSTR expanded_string;
  82
  83     WINE_TRACE("\n");
  84
  85     size = 0;
  86     size = ExpandEnvironmentStringsW(string, NULL, size);
  87     if (size == 0)
  88     {
  89         WINE_ERR("cannot expand env vars in %s: %lu\n",
  90                 wine_dbgstr_w(string), GetLastError());
  91         return NULL;
  92     }
  93     expanded_string = HeapAlloc(GetProcessHeap(), 0,
  94             (size + 1) * sizeof(WCHAR));
  95     if (ExpandEnvironmentStringsW(string, expanded_string, size) == 0)
  96     {
  97         WINE_ERR("cannot expand env vars in %s: %lu\n",
  98                 wine_dbgstr_w(string), GetLastError());
  99         HeapFree(GetProcessHeap(), 0, expanded_string);
 100         return NULL;
 101     }
 102     return expanded_string;
 103 }
 104
 105 /* Fill in service table entry for a specified service */
 106 static BOOL AddServiceElem(LPWSTR service_name,
 107         SERVICE_TABLE_ENTRYW *service_table_entry)
 108 {
 109     LONG ret;
 110     HKEY service_hkey = NULL;
 111     LPWSTR service_param_key = NULL;
 112     LPWSTR dll_name_short = NULL;
 113     LPWSTR dll_name_long = NULL;
 114     LPSTR dll_service_main = NULL;
 115     HMODULE library = NULL;
 116     LPSERVICE_MAIN_FUNCTIONW service_main_func = NULL;
 117     BOOL success = FALSE;
 118     DWORD reg_size;
 119     DWORD size;
 120
 121     WINE_TRACE("Adding element for %s\n", wine_dbgstr_w(service_name));
 122
 123     /* Construct registry path to the service's parameters key */
 124     size = lstrlenW(service_reg_path) + lstrlenW(L"\\") + lstrlenW(service_name) + lstrlenW(L"\\") +
 125            lstrlenW(L"Parameters") + 1;
 126     service_param_key = HeapAlloc(GetProcessHeap(), 0, size * sizeof(WCHAR));
 127     lstrcpyW(service_param_key, service_reg_path);
 128     lstrcatW(service_param_key, L"\\");
 129     lstrcatW(service_param_key, service_name);
 130     lstrcatW(service_param_key, L"\\");
 131     lstrcatW(service_param_key, L"Parameters");
 132     service_param_key[size - 1] = '\0';
 133     ret = RegOpenKeyExW(HKEY_LOCAL_MACHINE, service_param_key, 0,
 134             KEY_READ, &service_hkey);
 135     if (ret != ERROR_SUCCESS)
 136     {
 137         WINE_ERR("cannot open key %s, err=%ld\n",
 138                 wine_dbgstr_w(service_param_key), ret);
 139         goto cleanup;
 140     }
 141
 142     /* Find DLL associate with service from key */
 143     dll_name_short = GetRegValue(service_hkey, L"ServiceDll");
 144     if (!dll_name_short)
 145     {
 146         WINE_ERR("cannot find registry value ServiceDll for service %s\n",
 147                 wine_dbgstr_w(service_name));
 148         RegCloseKey(service_hkey);
 149         goto cleanup;
 150     }
 151
 152     /* Expand environment variables in ServiceDll name*/
 153     dll_name_long = ExpandEnv(dll_name_short);
 154     if (!dll_name_long)
 155     {
 156         WINE_ERR("failed to expand string %s\n",
 157                 wine_dbgstr_w(dll_name_short));
 158         RegCloseKey(service_hkey);
 159         goto cleanup;
 160     }
 161
 162     /* Look for alternate to default ServiceMain entry point */
 163     ret = RegQueryValueExA(service_hkey, "ServiceMain", NULL, NULL, NULL, &reg_size);
 164     if (ret == ERROR_SUCCESS)
 165     {
 166         /* Add space for potentially missing NULL terminator, allocate, and
 167          * fill with the registry value */
 168         size = reg_size + 1;
 169         dll_service_main = HeapAlloc(GetProcessHeap(), 0, size);
 170         ret = RegQueryValueExA(service_hkey, "ServiceMain", NULL, NULL,
 171                 (LPBYTE)dll_service_main, &reg_size);
 172         if (ret != ERROR_SUCCESS)
 173         {
 174             RegCloseKey(service_hkey);
 175             goto cleanup;
 176         }
 177         dll_service_main[size - 1] = '\0';
 178     }
 179     RegCloseKey(service_hkey);
 180
 181     /* Load the DLL and obtain a pointer to ServiceMain entry point */
 182     library = LoadLibraryExW(dll_name_long, NULL, LOAD_WITH_ALTERED_SEARCH_PATH);
 183     if (!library)
 184     {
 185         WINE_ERR("failed to load library %s, err=%lu\n",
 186                 wine_dbgstr_w(dll_name_long), GetLastError());
 187         goto cleanup;
 188     }
 189     if (dll_service_main)
 190     {
 191         service_main_func =
 192             (LPSERVICE_MAIN_FUNCTIONW) GetProcAddress(library, dll_service_main);
 193     }
 194     else
 195     {
 196         service_main_func =
 197             (LPSERVICE_MAIN_FUNCTIONW) GetProcAddress(library, "ServiceMain");
 198     }
 199     if (!service_main_func)
 200     {
 201         WINE_ERR("cannot locate ServiceMain procedure in DLL for %s\n",
 202                 wine_dbgstr_w(service_name));
 203         FreeLibrary(library);
 204         goto cleanup;
 205     }
 206
 207     if (GetProcAddress(library, "SvchostPushServiceGlobals"))
 208     {
 209         WINE_FIXME("library %s expects undocumented SvchostPushServiceGlobals function to be called\n",
 210                    wine_dbgstr_w(dll_name_long));
 211     }
 212
 213     /* Fill in the service table entry */
 214     service_table_entry->lpServiceName = service_name;
 215     service_table_entry->lpServiceProc = service_main_func;
 216     success = TRUE;
 217
 218 cleanup:
 219     HeapFree(GetProcessHeap(), 0, service_param_key);
 220     HeapFree(GetProcessHeap(), 0, dll_name_short);
 221     HeapFree(GetProcessHeap(), 0, dll_name_long);
 222     HeapFree(GetProcessHeap(), 0, dll_service_main);
 223     return success;
 224 }
 225
 226 /* Initialize the service table for a list (REG_MULTI_SZ) of services */
 227 static BOOL StartGroupServices(LPWSTR services)
 228 {
 229     LPWSTR service_name = NULL;
 230     SERVICE_TABLE_ENTRYW *service_table = NULL;
 231     DWORD service_count;
 232     BOOL ret;
 233
 234     /* Count the services to load */
 235     service_count = 0;
 236     service_name = services;
 237     while (*service_name != '\0')
 238     {
 239         ++service_count;
 240         service_name = service_name + lstrlenW(service_name);
 241         ++service_name;
 242     }
 243     WINE_TRACE("Service group contains %ld services\n", service_count);
 244
 245     /* Populate the service table */
 246     service_table = HeapAlloc(GetProcessHeap(), 0,
 247             (service_count + 1) * sizeof(SERVICE_TABLE_ENTRYW));
 248     service_count = 0;
 249     service_name = services;
 250     while (*service_name != '\0')
 251     {
 252         if (!AddServiceElem(service_name, &service_table[service_count]))
 253         {
 254             HeapFree(GetProcessHeap(), 0, service_table);
 255             return FALSE;
 256         }
 257         ++service_count;
 258         service_name = service_name + lstrlenW(service_name);
 259         ++service_name;
 260     }
 261     service_table[service_count].lpServiceName = NULL;
 262     service_table[service_count].lpServiceProc = NULL;
 263
 264     /* Start the services */
 265     if (!(ret = StartServiceCtrlDispatcherW(service_table)))
 266         WINE_ERR("StartServiceCtrlDispatcherW failed to start %s: %lu\n",
 267                 wine_dbgstr_w(services), GetLastError());
 268
 269     HeapFree(GetProcessHeap(), 0, service_table);
 270     return ret;
 271 }
 272
 273 /* Find the list of services associated with a group name and start those
 274  * services */
 275 static BOOL LoadGroup(PWCHAR group_name)
 276 {
 277     HKEY group_hkey = NULL;
 278     LPWSTR services = NULL;
 279     LONG ret;
 280
 281     WINE_TRACE("Loading service group for %s\n", wine_dbgstr_w(group_name));
 282
 283     /* Lookup group_name value of svchost registry entry */
 284     ret = RegOpenKeyExW(HKEY_LOCAL_MACHINE, svchost_path, 0,
 285             KEY_READ, &group_hkey);
 286     if (ret != ERROR_SUCCESS)
 287     {
 288         WINE_ERR("cannot open key %s, err=%ld\n",
 289                 wine_dbgstr_w(svchost_path), ret);
 290         return FALSE;
 291     }
 292     services = GetRegValue(group_hkey, group_name);
 293     RegCloseKey(group_hkey);
 294     if (!services)
 295     {
 296         WINE_ERR("cannot find registry value %s in %s\n",
 297                 wine_dbgstr_w(group_name), wine_dbgstr_w(svchost_path));
 298         return FALSE;
 299     }
 300
 301     /* Start services */
 302     if (!(ret = StartGroupServices(services)))
 303         WINE_TRACE("Failed to start service group\n");
 304
 305     HeapFree(GetProcessHeap(), 0, services);
 306     return ret;
 307 }
 308
 309 /* Load svchost group specified on the command line via the /k option */
 310 int __cdecl wmain(int argc, WCHAR *argv[])
 311 {
 312     int option_index;
 313
 314     WINE_TRACE("\n");
 315
 316     for (option_index = 1; option_index < argc; option_index++)
 317     {
 318         if (lstrcmpiW(argv[option_index], L"/k") == 0 || lstrcmpiW(argv[option_index], L"-k") == 0)
 319         {
 320             ++option_index;
 321             if (option_index >= argc)
 322             {
 323                 WINE_ERR("Must specify group to initialize\n");
 324                 return 0;
 325             }
 326             if (!LoadGroup(argv[option_index]))
 327             {
 328                 WINE_ERR("Failed to load requested group: %s\n",
 329                         wine_dbgstr_w(argv[option_index]));
 330                 return 0;
 331             }
 332         }
 333         else
 334         {
 335             WINE_FIXME("Unrecognized option: %s\n",
 336                     wine_dbgstr_w(argv[option_index]));
 337             return 0;
 338         }
 339     }
 340
 341     return 0;
 342 }