defer memory hook until after xInit

sjlombardo · sjlombardo · commit 94c88989f7c5 · 2018-10-29T17:58:34.000-04:00
diff --git a/src/crypto_impl.c b/src/crypto_impl.c
@@ -52,6 +52,7 @@ static volatile int default_plaintext_header_sz = 0;
 static volatile int default_hmac_algorithm = SQLCIPHER_HMAC_SHA512;
 static volatile int default_kdf_algorithm = SQLCIPHER_PBKDF2_HMAC_SHA512;
 static volatile int mem_security_on = 1;
+static volatile int mem_security_initialized = 0;
 static volatile int mem_security_activated = 0;
 static volatile unsigned int sqlcipher_activate_count = 0;
 static volatile sqlite3_mem_methods default_mem_methods;
@@ -147,8 +148,12 @@ static sqlite3_mem_methods sqlcipher_mem_methods = {
 };
 
 void sqlcipher_init_memmethods() {
-  sqlite3_config(SQLITE_CONFIG_GETMALLOC, &default_mem_methods);
-  sqlite3_config(SQLITE_CONFIG_MALLOC, &sqlcipher_mem_methods);
+  if(mem_security_initialized) return;
+  if(sqlite3_config(SQLITE_CONFIG_GETMALLOC, &default_mem_methods) != SQLITE_OK ||
+     sqlite3_config(SQLITE_CONFIG_MALLOC, &sqlcipher_mem_methods)  != SQLITE_OK) {
+    mem_security_on = mem_security_activated = 0;
+  }
+  mem_security_initialized = 1;
 }
 
 int sqlcipher_register_provider(sqlcipher_provider *p) {
diff --git a/src/malloc.c b/src/malloc.c
@@ -111,7 +111,17 @@ int sqlite3MallocInit(void){
   int rc;
   if( sqlite3GlobalConfig.m.xMalloc==0 ){
     sqlite3MemSetDefault();
-/* BEGIN SQLCIPHER */
+
+  memset(&mem0, 0, sizeof(mem0));
+  mem0.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
+  if( sqlite3GlobalConfig.pPage==0 || sqlite3GlobalConfig.szPage<512
+      || sqlite3GlobalConfig.nPage<=0 ){
+    sqlite3GlobalConfig.pPage = 0;
+    sqlite3GlobalConfig.szPage = 0;
+  }
+  rc = sqlite3GlobalConfig.m.xInit(sqlite3GlobalConfig.m.pAppData);
+  if( rc!=SQLITE_OK ) memset(&mem0, 0, sizeof(mem0));
+  /* BEGIN SQLCIPHER */
 #ifdef SQLITE_HAS_CODEC
     /* install wrapping functions for memory management
        that will wipe all memory allocated by SQLite
@@ -123,16 +133,6 @@ int sqlite3MallocInit(void){
 #endif
 /* END SQLCIPHER */
   }
-
-  memset(&mem0, 0, sizeof(mem0));
-  mem0.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
-  if( sqlite3GlobalConfig.pPage==0 || sqlite3GlobalConfig.szPage<512
-      || sqlite3GlobalConfig.nPage<=0 ){
-    sqlite3GlobalConfig.pPage = 0;
-    sqlite3GlobalConfig.szPage = 0;
-  }
-  rc = sqlite3GlobalConfig.m.xInit(sqlite3GlobalConfig.m.pAppData);
-  if( rc!=SQLITE_OK ) memset(&mem0, 0, sizeof(mem0));
   return rc;
 }
 
