Move utility function ot a different file

3 files changed, 79 insertions, 30 deletions

diff --git a/Frameworks/SPMySQLFramework/Source/SPMySQLConnection.m b/Frameworks/SPMySQLFramework/Source/SPMySQLConnection.m
index b143db19..d4146f58 100644
--- a/Frameworks/SPMySQLFramework/Source/SPMySQLConnection.m
+++ b/Frameworks/SPMySQLFramework/Source/SPMySQLConnection.m
@@ -34,10 +34,7 @@
 #include <pthread.h>
 #include <SystemConfiguration/SCNetworkReachability.h>
 #include <errno.h>
-#define __STDC_WANT_LIB_EXT1__ 1
 #include <string.h>
-#include <stdlib.h>
-#include <dlfcn.h>
 #import "SPMySQLUtilities.h"
 
 // Thread flag constant
@@ -56,7 +53,6 @@ const SPMySQLClientFlags SPMySQLConnectionOptions =
 const char *SPMySQLSSLPermissibleCiphers = "DHE-RSA-AES256-SHA:AES256-SHA:DHE-RSA-AES128-SHA:AES128-SHA:AES256-RMD:AES128-RMD:DES-CBC3-RMD:DHE-RSA-AES256-RMD:DHE-RSA-AES128-RMD:DHE-RSA-DES-CBC3-RMD:RC4-SHA:RC4-MD5:DES-CBC3-SHA:DES-CBC-SHA:EDH-RSA-DES-CBC3-SHA:EDH-RSA-DES-CBC-SHA";
 
 static void PasswordCallback(MYSQL *mysql, const char *plugin, void (^with_password)(const char *passwd));
-static errno_t LegacyMemsetS(void *ptr, rsize_t ignored, int value, rsize_t count);
 
 @implementation SPMySQLConnection
 
@@ -792,16 +788,8 @@ asm(".desc ___crashreporter_info__, 0x10");
 	else {
 		NSLog(@"%s: -getCString:maxLength:encoding: failed for password!", __PRETTY_FUNCTION__);
 	}
-	
-	// memset_s is 10.9+ only - if we added a link time dependency, SP wouldn't launch on older targets
-	static errno_t (*memsetPtr)(void *, rsize_t, int, rsize_t);
-	static dispatch_once_t findMemsetToken;
-	dispatch_once(&findMemsetToken, ^{
-		memsetPtr = dlsym(RTLD_DEFAULT, "memset_s");
-		if(!memsetPtr) memsetPtr = LegacyMemsetS;
-	});
-
-	memsetPtr(cBuffer, cLength, '\0', cLength); //clear password from memory
+
+	SPMySQLSafeEraseMemory(cBuffer, cLength); //clear password from memory
 	free(cBuffer);
 }
 
@@ -1240,18 +1228,3 @@ void PasswordCallback(MYSQL *mysql, const char *plugin, void (^with_password)(co
 	assert(mysql && mysql->sp_context);
 	[(SPMySQLConnection *)mysql->sp_context _mysqlConnection:mysql wantsPassword:with_password withPlugin:plugin];
 }
-
-/**
- * This function tries to emulate the important (to us) parts
- * of memset_s on pre 10.9 systems.
- *
- * The implementation is taken from the original memset_s proposal:
- *   http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1381.pdf
- */
-errno_t LegacyMemsetS(void *s, rsize_t smax __attribute__((unused)), int c, rsize_t n)
-{
-	volatile unsigned char * addr = (volatile unsigned char *)s;
-	while(n--) *addr++ = (unsigned char)c;
-	
-	return 0;
-}
diff --git a/Frameworks/SPMySQLFramework/Source/SPMySQLUtilities.h b/Frameworks/SPMySQLFramework/Source/SPMySQLUtilities.h
index 50f9d504..852ca685 100644
--- a/Frameworks/SPMySQLFramework/Source/SPMySQLUtilities.h
+++ b/Frameworks/SPMySQLFramework/Source/SPMySQLUtilities.h
@@ -1,5 +1,5 @@
 //
-//  Locking.h
+//  SPMySQLUtilities.h
 //  SPMySQLFramework
 //
 //  Created by Rowan Beentje (rowan.beent.je) on February 6, 2012
@@ -30,6 +30,16 @@
 
 #include <mach/mach_time.h>
 
+/**
+ * This function provides a memset() variant that cannot be optimized
+ * away by a compiler's dead store optimization.
+ *
+ * It will write cLength '\0' bytes to the buffer pointed to by cBuffer.
+ *
+ * @return See the documentation for memset_s in libc
+ */
+errno_t SPMySQLSafeEraseMemory(void *cBuffer, size_t cLength);
+
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wunused-function"
 
diff --git a/Frameworks/SPMySQLFramework/Source/SPMySQLUtilities.m b/Frameworks/SPMySQLFramework/Source/SPMySQLUtilities.m
new file mode 100644
index 00000000..3d147143
--- /dev/null
+++ b/Frameworks/SPMySQLFramework/Source/SPMySQLUtilities.m
@@ -0,0 +1,66 @@
+//
+//  SPMySQLUtilities.c
+//  SPMySQLFramework
+//
+//  Created by Max Lohrmann on 25.02.2018
+//  Copyright (c) 2018 Max Lohrmann. All rights reserved.
+//
+//  Permission is hereby granted, free of charge, to any person
+//  obtaining a copy of this software and associated documentation
+//  files (the "Software"), to deal in the Software without
+//  restriction, including without limitation the rights to use,
+//  copy, modify, merge, publish, distribute, sublicense, and/or sell
+//  copies of the Software, and to permit persons to whom the
+//  Software is furnished to do so, subject to the following
+//  conditions:
+//
+//  The above copyright notice and this permission notice shall be
+//  included in all copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+//  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+//  OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+//  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+//  HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+//  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+//  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+//  OTHER DEALINGS IN THE SOFTWARE.
+//
+//  More info at <https://github.com/sequelpro/sequelpro>
+
+#include <errno.h>
+#define __STDC_WANT_LIB_EXT1__ 1
+#include <string.h>
+#include <dlfcn.h>
+#include <dispatch/dispatch.h>
+
+#include "SPMySQLUtilities.h"
+
+static errno_t LegacyMemsetS(void *ptr, rsize_t ignored, int value, rsize_t count);
+
+errno_t SPMySQLSafeEraseMemory(void *cBuffer, size_t cLength) {
+	// memset_s is 10.9+ only - if we added a link time dependency, SP wouldn't launch on older targets
+	static errno_t (*memsetPtr)(void *, rsize_t, int, rsize_t);
+	static dispatch_once_t findMemsetToken;
+	dispatch_once(&findMemsetToken, ^{
+		memsetPtr = dlsym(RTLD_DEFAULT, "memset_s");
+		if(!memsetPtr) memsetPtr = &LegacyMemsetS;
+	});
+
+	return (*memsetPtr)(cBuffer, cLength, '\0', cLength);
+}
+
+/**
+ * This function tries to emulate the important (to us) parts
+ * of memset_s on pre 10.9 systems.
+ *
+ * The implementation is taken from the original memset_s proposal:
+ *   http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1381.pdf
+ */
+errno_t LegacyMemsetS(void *s, rsize_t smax __attribute__((unused)), int c, rsize_t n)
+{
+	volatile unsigned char * addr = (volatile unsigned char *)s;
+	while(n--) *addr++ = (unsigned char)c;
+
+	return 0;
+}