Authorization (draft) first done

AFAmazonS3Client/AFAmazonS3Client.m

@@ -21,11 +21,65 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#import <CommonCrypto/CommonHMAC.h>
 #import "AFAmazonS3Client.h"
 #import "AFXMLRequestOperation.h"
 
-NSString * const kAFAmazonS3BaseURLString = @"https://s3.amazonaws.com";
-NSString * const kAFAmazonS3BucketBaseURLFormatString = @"https://%@.s3.amazonaws.com";
+NSString * const kAFAmazonS3BaseURLString = @"http://s3.amazonaws.com";
+NSString * const kAFAmazonS3BucketBaseURLFormatString = @"http://%@.s3.amazonaws.com";
+
+static NSData * AFHMACSHA1EncodedDataFromStringWithKey(NSString *string, NSString *key) {
+    NSData *data = [string dataUsingEncoding:NSASCIIStringEncoding];
+    CCHmacContext context;
+    const char *keyCString = [key cStringUsingEncoding:NSASCIIStringEncoding];
+
+    CCHmacInit(&context, kCCHmacAlgSHA1, keyCString, strlen(keyCString));
+    CCHmacUpdate(&context, [data bytes], [data length]);
+
+    unsigned char digestRaw[CC_SHA1_DIGEST_LENGTH];
+    NSInteger digestLength = CC_SHA1_DIGEST_LENGTH;
+
+    CCHmacFinal(&context, digestRaw);
+
+    return [NSData dataWithBytes:digestRaw length:digestLength];
+}
+
+static NSString *AFRFC822FormatStringFromDate(NSDate *date) {
+    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
+    [dateFormatter setTimeZone:[NSTimeZone timeZoneWithName:@"GMT"]];
+    [dateFormatter setDateFormat:@"EEE, dd MMM yyyy HH:mm:ss z"];
+    [dateFormatter setLocale:[[NSLocale alloc] initWithLocaleIdentifier:@"en_US"]];
+
+    return [dateFormatter stringFromDate:date];
+}
+
+NSString * AFBase64EncodedStringFromData(NSData *data) {
+    NSUInteger length = [data length];
+    NSMutableData *mutableData = [NSMutableData dataWithLength:((length + 2) / 3) * 4];
+
+    uint8_t *input = (uint8_t *)[data bytes];
+    uint8_t *output = (uint8_t *)[mutableData mutableBytes];
+
+    for (NSUInteger i = 0; i < length; i += 3) {
+        NSUInteger value = 0;
+        for (NSUInteger j = i; j < (i + 3); j++) {
+            value <<= 8;
+            if (j < length) {
+                value |= (0xFF & input[j]);
+            }
+        }
+
+        static uint8_t const kAFBase64EncodingTable[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+        NSUInteger idx = (i / 3) * 4;
+        output[idx + 0] = kAFBase64EncodingTable[(value >> 18) & 0x3F];
+        output[idx + 1] = kAFBase64EncodingTable[(value >> 12) & 0x3F];
+        output[idx + 2] = (i + 1) < length ? kAFBase64EncodingTable[(value >> 6)  & 0x3F] : '=';
+        output[idx + 3] = (i + 2) < length ? kAFBase64EncodingTable[(value >> 0)  & 0x3F] : '=';
+    }
+
+    return [[NSString alloc] initWithData:mutableData encoding:NSASCIIStringEncoding];
+}
 
 #pragma mark -
 
@@ -260,4 +314,22 @@ - (void)setObjectWithMethod:(NSString *)method
     }
 }
 
+- (NSMutableURLRequest *)requestWithMethod:(NSString *)method
+                                      path:(NSString *)path
+                                parameters:(NSDictionary *)parameters
+{
+    NSMutableURLRequest *request = [super requestWithMethod:method path:path parameters:parameters];
+
+    NSString *canonicalizedResource = [NSString stringWithFormat:@"/%@%@", _bucket, path];
+    NSString *date = AFRFC822FormatStringFromDate([NSDate date]);
+    NSString *stringToSign = [NSString stringWithFormat:@"%@\n\n\n%@\n%@", method, date, canonicalizedResource];
+    NSData *hmac = AFHMACSHA1EncodedDataFromStringWithKey(stringToSign, _secret);
+    NSString *signature = AFBase64EncodedStringFromData(hmac);
+
+    [request setValue:date forHTTPHeaderField:@"Date"];
+    [request setValue:[NSString stringWithFormat:@"AWS %@:%@", _accessKey, signature] forHTTPHeaderField:@"Authorization"];
+
+    return request;
+}
+
 @end