dlls/crypt32/context.c

   1 /*
   2  * Copyright 2006 Juan Lang
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  17  */
  18 #include <assert.h>
  19 #include <stdarg.h>
  20 #include "windef.h"
  21 #include "winbase.h"
  22 #include "wincrypt.h"
  23 #include "wine/debug.h"
  24 #include "wine/list.h"
  25 #include "crypt32_private.h"
  26
  27 WINE_DEFAULT_DEBUG_CHANNEL(crypt);
  28
  29 typedef enum _ContextType {
  30     ContextTypeData,
  31     ContextTypeLink,
  32 } ContextType;
  33
  34 typedef struct _BASE_CONTEXT
  35 {
  36     LONG        ref;
  37     ContextType type;
  38 } BASE_CONTEXT, *PBASE_CONTEXT;
  39
  40 typedef struct _DATA_CONTEXT
  41 {
  42     LONG                   ref;
  43     ContextType            type; /* always ContextTypeData */
  44     PCONTEXT_PROPERTY_LIST properties;
  45 } DATA_CONTEXT, *PDATA_CONTEXT;
  46
  47 typedef struct _LINK_CONTEXT
  48 {
  49     LONG          ref;
  50     ContextType   type; /* always ContextTypeLink */
  51     PBASE_CONTEXT linked;
  52 } LINK_CONTEXT, *PLINK_CONTEXT;
  53
  54 #define CONTEXT_FROM_BASE_CONTEXT(p, s) ((LPBYTE)(p) - (s))
  55 #define BASE_CONTEXT_FROM_CONTEXT(p, s) (PBASE_CONTEXT)((LPBYTE)(p) + (s))
  56
  57 void *Context_CreateDataContext(size_t contextSize)
  58 {
  59     void *ret = CryptMemAlloc(contextSize + sizeof(DATA_CONTEXT));
  60
  61     if (ret)
  62     {
  63         PDATA_CONTEXT context = (PDATA_CONTEXT)((LPBYTE)ret + contextSize);
  64
  65         context->ref = 1;
  66         context->type = ContextTypeData;
  67         context->properties = ContextPropertyList_Create();
  68         if (!context->properties)
  69         {
  70             CryptMemFree(ret);
  71             ret = NULL;
  72         }
  73     }
  74     TRACE("returning %p\n", ret);
  75     return ret;
  76 }
  77
  78 void *Context_CreateLinkContext(unsigned int contextSize, void *linked, unsigned int extra,
  79  BOOL addRef)
  80 {
  81     void *context = CryptMemAlloc(contextSize + sizeof(LINK_CONTEXT) + extra);
  82
  83     TRACE("(%d, %p, %d)\n", contextSize, linked, extra);
  84
  85     if (context)
  86     {
  87         PLINK_CONTEXT linkContext = (PLINK_CONTEXT)BASE_CONTEXT_FROM_CONTEXT(
  88          context, contextSize);
  89         PBASE_CONTEXT linkedBase = BASE_CONTEXT_FROM_CONTEXT(linked,
  90          contextSize);
  91
  92         memcpy(context, linked, contextSize);
  93         linkContext->ref = 1;
  94         linkContext->type = ContextTypeLink;
  95         linkContext->linked = linkedBase;
  96         if (addRef)
  97             InterlockedIncrement(&linkedBase->ref);
  98         TRACE("%p's ref count is %d\n", context, linkContext->ref);
  99     }
 100     TRACE("returning %p\n", context);
 101     return context;
 102 }
 103
 104 void Context_AddRef(void *context, size_t contextSize)
 105 {
 106     PBASE_CONTEXT baseContext = BASE_CONTEXT_FROM_CONTEXT(context, contextSize);
 107
 108     InterlockedIncrement(&baseContext->ref);
 109 }
 110
 111 void *Context_GetExtra(const void *context, size_t contextSize)
 112 {
 113     PBASE_CONTEXT baseContext = BASE_CONTEXT_FROM_CONTEXT(context, contextSize);
 114
 115     assert(baseContext->type == ContextTypeLink);
 116     return (LPBYTE)baseContext + sizeof(LINK_CONTEXT);
 117 }
 118
 119 void *Context_GetLinkedContext(void *context, size_t contextSize)
 120 {
 121     PBASE_CONTEXT baseContext = BASE_CONTEXT_FROM_CONTEXT(context, contextSize);
 122
 123     assert(baseContext->type == ContextTypeLink);
 124     return CONTEXT_FROM_BASE_CONTEXT(((PLINK_CONTEXT)baseContext)->linked,
 125      contextSize);
 126 }
 127
 128 PCONTEXT_PROPERTY_LIST Context_GetProperties(const void *context, size_t contextSize)
 129 {
 130     PBASE_CONTEXT ptr = BASE_CONTEXT_FROM_CONTEXT(context, contextSize);
 131
 132     while (ptr && ptr->type == ContextTypeLink)
 133         ptr = ((PLINK_CONTEXT)ptr)->linked;
 134     return (ptr && ptr->type == ContextTypeData) ?
 135      ((PDATA_CONTEXT)ptr)->properties : NULL;
 136 }
 137
 138 void Context_Release(void *context, size_t contextSize,
 139  ContextFreeFunc dataContextFree)
 140 {
 141     PBASE_CONTEXT base = BASE_CONTEXT_FROM_CONTEXT(context, contextSize);
 142
 143     if (InterlockedDecrement(&base->ref) == 0)
 144     {
 145         TRACE("freeing %p\n", context);
 146         switch (base->type)
 147         {
 148         case ContextTypeData:
 149             ContextPropertyList_Free(((PDATA_CONTEXT)base)->properties);
 150             dataContextFree(context);
 151             break;
 152         case ContextTypeLink:
 153             /* The linked context is of the same type as this, so release
 154              * it as well, using the same offset and data free function.
 155              */
 156             Context_Release(CONTEXT_FROM_BASE_CONTEXT(
 157              ((PLINK_CONTEXT)base)->linked, contextSize), contextSize,
 158              dataContextFree);
 159             break;
 160         default:
 161             assert(0);
 162         }
 163         CryptMemFree(context);
 164     }
 165     else
 166         TRACE("%p's ref count is %d\n", context, base->ref);
 167 }
 168
 169 void Context_CopyProperties(const void *to, const void *from,
 170  size_t contextSize)
 171 {
 172     PCONTEXT_PROPERTY_LIST toProperties, fromProperties;
 173
 174     toProperties = Context_GetProperties(to, contextSize);
 175     fromProperties = Context_GetProperties(from, contextSize);
 176     assert(toProperties && fromProperties);
 177     ContextPropertyList_Copy(toProperties, fromProperties);
 178 }
 179
 180 struct ContextList
 181 {
 182     PCWINE_CONTEXT_INTERFACE contextInterface;
 183     size_t contextSize;
 184     CRITICAL_SECTION cs;
 185     struct list contexts;
 186 };
 187
 188 struct ContextList *ContextList_Create(
 189  PCWINE_CONTEXT_INTERFACE contextInterface, size_t contextSize)
 190 {
 191     struct ContextList *list = CryptMemAlloc(sizeof(struct ContextList));
 192
 193     if (list)
 194     {
 195         list->contextInterface = contextInterface;
 196         list->contextSize = contextSize;
 197         InitializeCriticalSection(&list->cs);
 198         list->cs.DebugInfo->Spare[0] = (DWORD_PTR)(__FILE__ ": ContextList.cs");
 199         list_init(&list->contexts);
 200     }
 201     return list;
 202 }
 203
 204 static inline struct list *ContextList_ContextToEntry(const struct ContextList *list,
 205  const void *context)
 206 {
 207     struct list *ret;
 208
 209     if (context)
 210         ret = Context_GetExtra(context, list->contextSize);
 211     else
 212         ret = NULL;
 213     return ret;
 214 }
 215
 216 static inline void *ContextList_EntryToContext(const struct ContextList *list,
 217  struct list *entry)
 218 {
 219     return (LPBYTE)entry - sizeof(LINK_CONTEXT) - list->contextSize;
 220 }
 221
 222 void *ContextList_Add(struct ContextList *list, void *toLink, void *toReplace)
 223 {
 224     void *context;
 225
 226     TRACE("(%p, %p, %p)\n", list, toLink, toReplace);
 227
 228     context = Context_CreateLinkContext(list->contextSize, toLink,
 229      sizeof(struct list), TRUE);
 230     if (context)
 231     {
 232         struct list *entry = ContextList_ContextToEntry(list, context);
 233
 234         TRACE("adding %p\n", context);
 235         EnterCriticalSection(&list->cs);
 236         if (toReplace)
 237         {
 238             struct list *existing = ContextList_ContextToEntry(list, toReplace);
 239
 240             entry->prev = existing->prev;
 241             entry->next = existing->next;
 242             entry->prev->next = entry;
 243             entry->next->prev = entry;
 244             existing->prev = existing->next = existing;
 245             list->contextInterface->free(toReplace);
 246         }
 247         else
 248             list_add_head(&list->contexts, entry);
 249         LeaveCriticalSection(&list->cs);
 250     }
 251     return context;
 252 }
 253
 254 void *ContextList_Enum(struct ContextList *list, void *pPrev)
 255 {
 256     struct list *listNext;
 257     void *ret;
 258
 259     EnterCriticalSection(&list->cs);
 260     if (pPrev)
 261     {
 262         struct list *prevEntry = ContextList_ContextToEntry(list, pPrev);
 263
 264         listNext = list_next(&list->contexts, prevEntry);
 265         list->contextInterface->free(pPrev);
 266     }
 267     else
 268         listNext = list_next(&list->contexts, &list->contexts);
 269     LeaveCriticalSection(&list->cs);
 270
 271     if (listNext)
 272     {
 273         ret = ContextList_EntryToContext(list, listNext);
 274         list->contextInterface->duplicate(ret);
 275     }
 276     else
 277         ret = NULL;
 278     return ret;
 279 }
 280
 281 void ContextList_Delete(struct ContextList *list, void *context)
 282 {
 283     struct list *entry = ContextList_ContextToEntry(list, context);
 284
 285     EnterCriticalSection(&list->cs);
 286     list_remove(entry);
 287     LeaveCriticalSection(&list->cs);
 288     list->contextInterface->free(context);
 289 }
 290
 291 static void ContextList_Empty(struct ContextList *list)
 292 {
 293     struct list *entry, *next;
 294
 295     EnterCriticalSection(&list->cs);
 296     LIST_FOR_EACH_SAFE(entry, next, &list->contexts)
 297     {
 298         const void *context = ContextList_EntryToContext(list, entry);
 299
 300         TRACE("removing %p\n", context);
 301         list_remove(entry);
 302         list->contextInterface->free(context);
 303     }
 304     LeaveCriticalSection(&list->cs);
 305 }
 306
 307 void ContextList_Free(struct ContextList *list)
 308 {
 309     ContextList_Empty(list);
 310     list->cs.DebugInfo->Spare[0] = 0;
 311     DeleteCriticalSection(&list->cs);
 312     CryptMemFree(list);
 313 }