From e10cc0c1803c598a7518b6c8b28195e20f0eb12e Mon Sep 17 00:00:00 2001
From: Michael Kirk <michael.code@endoftheworl.de>
Date: Wed, 31 May 2017 11:30:05 -0700
Subject: [PATCH 1/2] determine if recipient identity change is unseen

// FREEBIE
---
 .../TSStorageManager+IdentityKeyStore.h        |  7 +++++++
 .../TSStorageManager+IdentityKeyStore.m        | 18 ++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.h b/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.h
index 841d7997a..0244f7b03 100644
--- a/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.h
+++ b/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.h
@@ -40,6 +40,13 @@ extern NSString *const TSStorageManagerTrustedKeysCollection;
  */
 - (nullable OWSRecipientIdentity *)unconfirmedIdentityThatShouldBlockSendingForRecipientId:(NSString *)recipientId;
 
+/**
+ * @param   recipientId unique stable identifier for the recipient, e.g. e164 phone number
+ * @returns YES if the recipient's id has not been marked as seen (and it's not a TOFU situation)
+ *          NO if the recipient's current id has been seen, or if it's the users first key
+ */
+- (BOOL)hasUnseenIdentityChangeForRecipientId:(NSString *)recipientId;
+
 - (void)generateNewIdentityKey;
 - (nullable NSData *)identityKeyForRecipientId:(NSString *)recipientId;
 - (void)removeIdentityKeyForRecipient:(NSString *)receipientId;
diff --git a/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.m b/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.m
index c6ee65256..925e09567 100644
--- a/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.m
+++ b/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.m
@@ -278,6 +278,24 @@ const NSTimeInterval kIdentityKeyStoreNonBlockingSecondsThreshold = 5.0;
     }
 }
 
+
+- (BOOL)hasUnseenIdentityChangeForRecipientId:(NSString *)recipientId
+{
+    OWSAssert(recipientId != nil);
+
+    OWSRecipientIdentity *recipientIdentity = [OWSRecipientIdentity fetchObjectWithUniqueID:recipientId];
+
+    if (!recipientIdentity) {
+        return NO;
+    }
+
+    if (recipientIdentity.isFirstKnownKey) {
+        return NO;
+    }
+
+    return !recipientIdentity.wasSeen;
+}
+
 @end
 
 NS_ASSUME_NONNULL_END

From ebd4800e21a1dd3410bfa498f986706c5c71aa4c Mon Sep 17 00:00:00 2001
From: Michael Kirk <michael.code@endoftheworl.de>
Date: Wed, 31 May 2017 17:40:59 -0700
Subject: [PATCH 2/2] return unseen identity rather than bool

This turns out to be more versitile for the client app

// FREEBIE
---
 .../TSStorageManager+IdentityKeyStore.h       |  7 +--
 .../TSStorageManager+IdentityKeyStore.m       | 43 +++++++++++--------
 2 files changed, 29 insertions(+), 21 deletions(-)

diff --git a/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.h b/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.h
index 0244f7b03..e178b7f3a 100644
--- a/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.h
+++ b/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.h
@@ -42,10 +42,11 @@ extern NSString *const TSStorageManagerTrustedKeysCollection;
 
 /**
  * @param   recipientId unique stable identifier for the recipient, e.g. e164 phone number
- * @returns YES if the recipient's id has not been marked as seen (and it's not a TOFU situation)
- *          NO if the recipient's current id has been seen, or if it's the users first key
+ * @returns nil if the recipient's current id has been seen, or if it's the users first key
+ *          else returns the unseen identity
+ *
  */
-- (BOOL)hasUnseenIdentityChangeForRecipientId:(NSString *)recipientId;
+- (nullable OWSRecipientIdentity *)unseenIdentityChangeForRecipientId:(NSString *)recipientId;
 
 - (void)generateNewIdentityKey;
 - (nullable NSData *)identityKeyForRecipientId:(NSString *)recipientId;
diff --git a/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.m b/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.m
index 925e09567..2c78f6f48 100644
--- a/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.m
+++ b/src/Storage/AxolotlStore/TSStorageManager+IdentityKeyStore.m
@@ -199,6 +199,31 @@ const NSTimeInterval kIdentityKeyStoreNonBlockingSecondsThreshold = 5.0;
     }
 }
 
+- (nullable OWSRecipientIdentity *)unseenIdentityChangeForRecipientId:(NSString *)recipientId
+{
+    OWSAssert(recipientId != nil);
+
+    @synchronized([[self class] sharedIdentityKeyLock])
+    {
+        OWSRecipientIdentity *currentIdentity = [OWSRecipientIdentity fetchObjectWithUniqueID:recipientId];
+        if (currentIdentity == nil) {
+            // No preexisting key, Trust On First Use
+            return nil;
+        }
+
+        if (currentIdentity.isFirstKnownKey) {
+            return nil;
+        }
+
+        if (currentIdentity.wasSeen) {
+            return nil;
+        }
+
+        // identity not yet seen
+        return currentIdentity;
+    }
+}
+
 - (BOOL)isTrustedKey:(NSData *)identityKey forSendingToIdentity:(nullable OWSRecipientIdentity *)recipientIdentity
 {
     OWSAssert(identityKey != nil);
@@ -278,24 +303,6 @@ const NSTimeInterval kIdentityKeyStoreNonBlockingSecondsThreshold = 5.0;
     }
 }
 
-
-- (BOOL)hasUnseenIdentityChangeForRecipientId:(NSString *)recipientId
-{
-    OWSAssert(recipientId != nil);
-
-    OWSRecipientIdentity *recipientIdentity = [OWSRecipientIdentity fetchObjectWithUniqueID:recipientId];
-
-    if (!recipientIdentity) {
-        return NO;
-    }
-
-    if (recipientIdentity.isFirstKnownKey) {
-        return NO;
-    }
-
-    return !recipientIdentity.wasSeen;
-}
-
 @end
 
 NS_ASSUME_NONNULL_END