From 93c7f15214a15932f3ff87fd92a4388c74d98efa Mon Sep 17 00:00:00 2001
From: Anakin Zheng <anakinmac@gmail.com>
Date: Mon, 19 May 2014 22:50:16 -0400
Subject: [PATCH] Use codesign verification to do dmc check

---
 Classes/smcWrapper.m                    | 37 ++++++++++++++++---------
 smcFanControl.xcodeproj/project.pbxproj |  8 +++---
 2 files changed, 28 insertions(+), 17 deletions(-)

diff --git a/Classes/smcWrapper.m b/Classes/smcWrapper.m
index 15d6e00..0477d31 100755
--- a/Classes/smcWrapper.m
+++ b/Classes/smcWrapper.m
@@ -24,8 +24,6 @@
 #import "smcWrapper.h"
 #import <CommonCrypto/CommonDigest.h>
 
-//TODO: This is the smcFanControl 2.5ß checksum, it needs to be updated for the next release.
-NSString * const smc_checksum=@"03548c5634bd01315b19c46bf329cceb";
 static NSArray *allSensors = nil;
 
 
@@ -153,26 +151,39 @@ static NSArray *allSensors = nil;
 }	
 
 
-+ (NSString*)createCheckSum:(NSString*)path {
-    NSData *d=[NSData dataWithContentsOfMappedFile:path];
-    unsigned char result[CC_MD5_DIGEST_LENGTH];
-    CC_MD5((void *)[d bytes], [d length], result);
-    NSMutableString *ret = [NSMutableString stringWithCapacity:CC_MD5_DIGEST_LENGTH*2];
-    int i;
-    for(i = 0; i<CC_MD5_DIGEST_LENGTH; i++) {
-        [ret appendFormat:@"%02x",result[i]];
++ (BOOL)validateSMC:(NSString*)path
+{
+    SecStaticCodeRef ref = NULL;
+    
+    NSURL * url = [NSURL URLWithString:path];
+    
+    OSStatus status;
+    
+    // obtain the cert info from the executable
+    status = SecStaticCodeCreateWithPath((CFURLRef)url, kSecCSDefaultFlags, &ref);
+    
+    if (status != noErr) {
+        return false;
     }
-    return ret;
+    
+    status = SecStaticCodeCheckValidity(ref, kSecCSDefaultFlags, nil);
+    
+    if (status != noErr) {
+        NSLog(@"Codesign verification failed: Error id = %d",status);
+        return false;
+    }
+
+    return true;
 }
 
 //call smc binary with setuid rights and apply
 // The smc binary is given root permissions in FanControl.m with the setRights method.
 +(void)setKey_external:(NSString *)key value:(NSString *)value{
 	NSString *launchPath = [[NSBundle mainBundle]   pathForResource:@"smc" ofType:@""];
-	NSString *checksum=[smcWrapper createCheckSum:launchPath];
+    
     //first check if it's the right binary (security)
     // MW: Disabled smc binary checksum. This should be re-enabled in an official release.
-	if (![checksum  isEqualToString:smc_checksum]) {
+	if (![smcWrapper validateSMC:launchPath]) {
 		NSLog(@"smcFanControl: Security Error: smc-binary is not the distributed one");
 		return;
 	}
diff --git a/smcFanControl.xcodeproj/project.pbxproj b/smcFanControl.xcodeproj/project.pbxproj
index d750ef0..7f0849e 100644
--- a/smcFanControl.xcodeproj/project.pbxproj
+++ b/smcFanControl.xcodeproj/project.pbxproj
@@ -433,8 +433,8 @@
 				ALWAYS_SEARCH_USER_PATHS = NO;
 				CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
-				CODE_SIGN_IDENTITY = "Mac Developer";
-				"CODE_SIGN_IDENTITY[sdk=macosx*]" = "Mac Developer";
+				CODE_SIGN_IDENTITY = "Mac Developer: Yancheng Zheng (5FNT3EVMK3)";
+				"CODE_SIGN_IDENTITY[sdk=macosx*]" = "Mac Developer: Yancheng Zheng (5FNT3EVMK3)";
 				COPY_PHASE_STRIP = NO;
 				GCC_C_LANGUAGE_STANDARD = gnu99;
 				GCC_DYNAMIC_NO_PIC = NO;
@@ -460,8 +460,8 @@
 				ALWAYS_SEARCH_USER_PATHS = NO;
 				CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
-				CODE_SIGN_IDENTITY = "Mac Developer";
-				"CODE_SIGN_IDENTITY[sdk=macosx*]" = "Mac Developer";
+				CODE_SIGN_IDENTITY = "Mac Developer: Yancheng Zheng (5FNT3EVMK3)";
+				"CODE_SIGN_IDENTITY[sdk=macosx*]" = "Mac Developer: Yancheng Zheng (5FNT3EVMK3)";
 				COPY_PHASE_STRIP = YES;
 				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
 				GCC_C_LANGUAGE_STANDARD = gnu99;