Stickers sporadically not loading

[chengw01]

• I have searched open and closed issues for duplicates
• I am submitting a bug report for existing functionality that does not work as intended
• This isn't a feature request or a discussion topic

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Bug description

Starting morning of September 14th (Eastern time) stickers sporadically fail to load with just the reload button which won't resolve the issue. This progressively got worse throughout the day until no stickers will load. It is marginally better on September 15th. There is no rhythm or rhythm on which stickers will work or not, both animated and static stickers appear to have this problem. Both parties are using Signal on iOS devices on 7.28 (328).

The debug logs at the time of receiving the stickers seem to indicate failure to download an attachment (presumably the sticker) due to failure to decrypt with a "Bad hmac" error

2024/09/14 22:10:30:884 💛 [AttachmentDownloadManagerImpl.swift:440 downloadRecord(_:)]: Downloading attachment 2158 2024/09/14 22:10:31:707 ❤️ [Cryptography.swift:597 decryptFile(at:metadata:validateHmacAndDigest:outputBlockSize:output:)]: assertionError: Bad hmac 2024/09/14 22:10:31:708 ❤️ [AttachmentDownloadManagerImpl.swift:556 downloadRecord(_:)]: Failed to validate: OWSAssertionError(description: "Bad hmac") 2024/09/14 22:10:31:708 ❤️ [AttachmentDownloadManagerImpl.swift:330 didFailToDownload(_:isRetryable:)]: Failed download of attachment 2158

Steps to reproduce

• Send stickers to recipient on iOS
• Notice some stickers fail to load on the recipient iOS device

Actual result: Stickers fail to load with a button to retry

Expected result: Stickers load and if animated, play correctly

Device info

Device: iPhone 13 Mini
iOS version: 17.6.1
Signal version: 7.28

Link to debug log

https://debuglogs.org/ios/7.28.0/57f91b2b4304300aaacedbc80ed517951741d7973849fc527f3e5dc97c4487ba.zip

[chengw01]

As a test I switched back to my old Android device (presumably changing the hmac key) and there was no issue with the stickers loading, however when I switched back to iOS the issue reoccurred. There also appears to be times where this is not a problem. It was sporadic this morning (15th), no issues in the afternoon, but persistent in the evening. Hope that helps!