BrowserID improvements

* Parse email address out of assertion rather than requiring it to be provided separately.
* Also get the expiration date, and don't return assertions that have expired.

Conflicts:
	Source/API/TDReplication.h
	Source/API/TDReplication.m

Author: snej

Source/TDBase64.h

@@ -13,4 +13,8 @@
 + (NSString*) encode:(NSData*) rawBytes;
 + (NSData*) decode:(const char*) string length:(size_t) inputLength;
 + (NSData*) decode:(NSString*) string;
+
+/** Decodes the URL-safe Base64 variant that uses '-' and '_' instead of '+' and '/', and omits trailing '=' characters. */
++ (NSData*) decodeURLSafe: (NSString*)string;
++ (NSData*) decodeURLSafe: (const char*)string length: (size_t)inputLength;
 @end

Source/TDBase64.m

@@ -31,6 +31,9 @@ + (void) initialize {
         for (NSUInteger i = 0; i < sizeof(kEncodingTable); i++) {
             kDecodingTable[kEncodingTable[i]] = (int8_t)i;
         }
+        // Alternate characters used in the URL-safe Base64 encoding (RFC 4648, sec. 5)
+        kDecodingTable['-'] = 62;
+        kDecodingTable['='] = 63;
     }
 }
 
@@ -69,10 +72,14 @@ + (NSString*) encode: (NSData*)rawBytes {
 
 
 + (NSData*) decode: (const char*)string length: (size_t)inputLength {
-    if ((string == NULL) || (inputLength % 4 != 0)) {
+        return nil;
+    return [self decodeURLSafe: string length: inputLength];
+}
+
++ (NSData*) decodeURLSafe: (const char*)string length: (size_t)inputLength {
+    if (string == NULL)
         return nil;
-    }
-    
     while (inputLength > 0 && string[inputLength - 1] == '=') {
         inputLength--;
     }
@@ -112,4 +119,10 @@ + (NSData*) decode:(NSString*) string {
 }
 
 
++ (NSData*) decodeURLSafe: (NSString*)string {
+    NSData* ascii = [string dataUsingEncoding: NSASCIIStringEncoding];
+    return [self decodeURLSafe: ascii.bytes length: ascii.length];
+}
+
+
 @end

Source/TDBrowserIDAuthorizer.h

@@ -12,12 +12,12 @@
 
 + (NSURL*) originForSite: (NSURL*)url;
 
-+ (void) registerAssertion: (NSString*)assertion
-           forEmailAddress: (NSString*)email
-                    toSite: (NSURL*)site;
 
 - (id) initWithEmailAddress: (NSString*)emailAddress;
 
 @property (readonly) NSString* emailAddress;
 
+- (NSString*) assertionForSite: (NSURL*)site;
+
 @end

Source/TDBrowserIDAuthorizer.m

@@ -7,14 +7,42 @@
 //
 
 #import "TDBrowserIDAuthorizer.h"
-
 
 static NSMutableDictionary* sAssertions;
 
 
 @implementation TDBrowserIDAuthorizer
 
 
+static NSDictionary* decodeComponent(NSArray* components, NSUInteger index) {
+    NSData* bodyData = [TDBase64 decodeURLSafe: components[index]];
+    if (!bodyData)
+        return nil;
+    return $castIf(NSDictionary, [TDJSON JSONObjectWithData: bodyData options: 0 error: NULL]);
+}
+
+
+static bool parseAssertion(NSString* assertion,
+                           NSString** outEmail, NSString** outOrigin, NSDate** outExp)
+{
+    // https://github.com/mozilla/id-specs/blob/prod/browserid/index.md
+    // http://self-issued.info/docs/draft-jones-json-web-token-04.html
+    NSArray* components = [assertion componentsSeparatedByString: @"."];
+    if (components.count < 4)
+        return false;
+    NSDictionary* body = decodeComponent(components, 1);
+    NSDictionary* principal = $castIf(NSDictionary, body[@"principal"]);
+    *outEmail = $castIf(NSString, principal[@"email"]);
+
+    body = decodeComponent(components, 3);
+    *outOrigin = $castIf(NSString, body[@"aud"]);
+    NSNumber* exp = $castIf(NSNumber, body[@"exp"]);
+    *outExp = exp ? [NSDate dateWithTimeIntervalSince1970: exp.doubleValue / 1000.0] : nil;
+    return *outEmail != nil && *outOrigin != nil && *outExp != nil;
+}
+
+
 + (NSURL*) originForSite: (NSURL*)url {
     NSString* scheme = url.scheme.lowercaseString;
     NSMutableString* str = [NSMutableString stringWithFormat: @"%@://%@",
@@ -30,27 +58,27 @@ + (NSURL*) originForSite: (NSURL*)url {
 }
 
 
-+ (void) registerAssertion: (NSString*)assertion
-           forEmailAddress: (NSString*)email
-                    toSite: (NSURL*)site
-{
+        return nil;
+    id key = @[email, origin];
     @synchronized(self) {
         if (!sAssertions)
             sAssertions = [NSMutableDictionary dictionary];
-        id key = @[email, [self originForSite: site]];
         sAssertions[key] = assertion;
     }
+    return email;
 }
 
 
 + (NSString*) takeAssertionForEmailAddress: (NSString*)email
                                       site: (NSURL*)site
 {
+    id key = @[email, [[self originForSite: site] absoluteString]];
     @synchronized(self) {
-        id key = @[email, [self originForSite: site]];
-        NSString* assertion = sAssertions[key];
-        //[sAssertions removeObjectForKey: key];
-        return assertion;
     }
 }
 
@@ -69,6 +97,18 @@ - (id) initWithEmailAddress: (NSString*)emailAddress {
 }
 
 
+- (NSString*) assertionForSite: (NSURL*)site {
+    NSString* assertion = [[self class] takeAssertionForEmailAddress: _emailAddress site: site];
+    if (!assertion)
+        return nil;
+    NSString* email, *origin;
+    NSDate* exp;
+    if (!parseAssertion(assertion, &email, &origin, &exp) || exp.timeIntervalSinceNow < 0)
+        return nil;
+    return assertion;
+}
+
+
 - (NSString*) authorizeURLRequest: (NSMutableURLRequest*)request
                          forRealm: (NSString*)realm
 {
@@ -91,10 +131,36 @@ - (NSString*) loginPath {
 
 
 - (NSDictionary*) loginParametersForSite: (NSURL*)site {
-    NSString* assertion = [[self class] takeAssertionForEmailAddress: _emailAddress site: site];
-    if (!assertion)
-        return nil;
-    return @{@"assertion": assertion};
 }
 
 @end
+
+
+
+
+TestCase(TEBrowserIDAuthorizer) {
+    NSString* email, *origin;
+    NSDate* exp;
+    CAssert(!parseAssertion(@"", &email, &origin, &exp));
+
+    // This is an assertion generated by persona.org on 1/13/2013.
+    NSString* sampleAssertion = @"eyJhbGciOiJSUzI1NiJ9.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.RnDK118nqL2wzpLCVRzw1MI4IThgeWpul9jPl6ypyyxRMMTurlJbjFfs-BXoPaOem878G8-4D2eGWS6wd307k7xlPysevYPogfFWxK_eDHwkTq3Ts91qEDqrdV_JtgULC8c1LvX65E0TwW_GL_TM94g3CvqoQnGVxxoaMVye4ggvR7eOZjimWMzUuu4Lo9Z-VBHBj7XM0UMBie57CpGwH4_Wkv0V_LHZRRHKdnl9ISp_aGwfBObTcHG9v0P3BW9vRrCjihIn0SqOJQ9obl52rMf84GD4Lcy9NIktzfyka70xR9Sh7ALotW7rWywsTzMTu3t8AzMz2MJgGjvQmx49QA~eyJhbGciOiJEUzEyOCJ9.eyJleHAiOjEzNTgyOTY0Mzg0OTUsImF1ZCI6Imh0dHA6Ly9sb2NhbGhvc3Q6NDk4NC8ifQ.4FV2TrUQffDya0MOxOQlzJQbDNvCPF2sfTIJN7KOLvvlSFPknuIo5g";
+    CAssert(parseAssertion(sampleAssertion, &email, &origin, &exp));
+    CAssertEqual(email, @"jens@mooseyard.com");
+    CAssertEqual(origin, @"http://localhost:4984/");
+    CAssertEq((SInt64)exp.timeIntervalSinceReferenceDate, 379989238);
+
+    // Register and retrieve the sample assertion:
+    NSURL* originURL = [NSURL URLWithString: origin];
+    CAssertEqual([TDBrowserIDAuthorizer registerAssertion: sampleAssertion], email);
+    NSString* gotAssertion = [TDBrowserIDAuthorizer takeAssertionForEmailAddress: email
+                                                                            site: originURL];
+    CAssertEqual(gotAssertion, sampleAssertion);
+    
+    // -assertionForSite: should return nil because the assertion has expired by now:
+    TDBrowserIDAuthorizer* auth = [[TDBrowserIDAuthorizer alloc] initWithEmailAddress: email];
+    CAssertEqual(auth.emailAddress, email);
+    CAssertEqual([auth assertionForSite: originURL], nil);
+}

TouchDB.xcodeproj/project.pbxproj

@@ -1836,7 +1836,7 @@
 		08FB7793FE84155DC02AAC07 /* Project object */ = {
 			isa = PBXProject;
 			attributes = {
-				LastUpgradeCheck = 0440;
 			};
 			buildConfigurationList = 1DEB923508733DC60010E9CD /* Build configuration list for PBXProject "TouchDB" */;
 			compatibilityVersion = "Xcode 3.2";
@@ -2706,13 +2706,15 @@
 		275A29261649C58900B0D8EE /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				COMBINE_HIDPI_IMAGES = YES;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 			};
 			name = Debug;
 		};
 		275A29271649C58900B0D8EE /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				COMBINE_HIDPI_IMAGES = YES;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 			};
 			name = Release;