935a8fe37a
Phase 2 of docs/frost-batch-signing.md. Pure refactor: proposals still carry one event, the wire is byte-identical, and every test passes unchanged -- 344 jvmTest and 217 testDebugUnitTest, none of them edited in this commit. advance() now loops over FrostSigningItem rows rather than reading the first one. One nonce per item, one aggregate per item, one Session.create per item, one partial signature per item, one signature per item. The signer set, the public shares, the tweak cache and the approval stay shared, because they are the terms that do not enter e = H(R‖P‖m). The coordinator's aggregation is the place where that distinction bites: it builds one AggregatedNonce per item, each from that item's nonce from each chosen signer. Reusing one across two items would be reusing R across two messages. ## The payload codec, early joinPayload/splitPayload land here rather than with the wire change, because at a batch of one a comma join is the identity -- the payload is the bare value it has always been. That leaves Phase 3 to the proposal encoding alone. splitPayload is strict: a payload that is not exactly the batch's length is dropped rather than truncated or padded. It runs in orderedNonces, orderedPartialSignatures and splitForSession -- never in record(), which stores payloads without parsing them so that a nonce can arrive before the proposal that would give it a length to check against. ## Two short-circuits, and one trap in the first advance() runs on every arriving message, so at a batch of k it was k native key generations, k Session.creates and k signs each time, usually to discover there was nothing left to do. - Nonces are generated by `lazy`. The obvious version -- a guard computing `ownNonce == null || (isSigner() && ownPartial == null)` -- is wrong, and wrong in a way that reads fine and fails every signing test: the coordinator settles the signer set further down the same pass, so isSigner() at the top is false on exactly the pass where the coordinator goes on to sign, and the nonces are never generated. Reproduced as IndexOutOfBounds before switching to lazy, which has no prediction to make. - A device that is neither signing nor aggregating leaves before building any FROST session, rather than building k of them to do nothing with. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
This is a Kotlin Multiplatform project targeting Android, iOS, Desktop (JVM).
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/composeApp is for code that will be shared across your Compose Multiplatform applications. It contains several subfolders:
- commonMain is for code that’s common for all targets.
- Other folders are for Kotlin code that will be compiled for only the platform indicated in the folder name. For example, if you want to use Apple’s CoreCrypto for the iOS part of your Kotlin app, the iosMain folder would be the right place for such calls. Similarly, if you want to edit the Desktop (JVM) specific part, the jvmMain folder is the appropriate location.
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/iosApp contains iOS applications. Even if you’re sharing your UI with Compose Multiplatform, you need this entry point for your iOS app. This is also where you should add SwiftUI code for your project.
Build and Run Android Application
To build and run the development version of the Android app, use the run configuration from the run widget in your IDE’s toolbar or build it directly from the terminal:
- on macOS/Linux
./gradlew :composeApp:assembleDebug - on Windows
.\gradlew.bat :composeApp:assembleDebug
Build and Run Desktop (JVM) Application
To build and run the development version of the desktop app, use the run configuration from the run widget in your IDE’s toolbar or run it directly from the terminal:
- on macOS/Linux
./gradlew :composeApp:run - on Windows
.\gradlew.bat :composeApp:run
Build and Run iOS Application
To build and run the development version of the iOS app, use the run configuration from the run widget in your IDE’s toolbar or open the /iosApp directory in Xcode and run it from there.
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