March 2014 update

Task/SHA-256/Objective-C/sha-256.m

@@ -0,0 +1,21 @@
+#import <CommonCrypto/CommonHMAC.h>
+
+@implementation AppDelegate
+
+- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
+ NSString* key = @"secret";
+ NSString* data = @"Message";
+
+ const char *cKey = [key cStringUsingEncoding:NSASCIIStringEncoding];
+ const char *cData = [data cStringUsingEncoding:NSASCIIStringEncoding];
+ unsigned char cHMAC[CC_SHA256_DIGEST_LENGTH];
+ CCHmac(kCCHmacAlgSHA256, cKey, strlen(cKey), cData, strlen(cData), cHMAC);
+
+ NSMutableString* result = [NSMutableString stringWithCapacity:(CC_SHA256_DIGEST_LENGTH * 2)];
+	
+  for(CC_LONG i = 0; i < CC_SHA256_DIGEST_LENGTH; i++)
+   [result appendFormat:@"%02x", cHMAC[i]];
+
+  NSLog(@"Sha-256: %@", result);
+
+}