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jackandGitHub
e9275cb3d8
Split-out safe half of #1437 (the kind-1402 wire migration stays held for Android coordination). Docs (README/WHITEPAPER/PRIVACY_POLICY/privacy-assessment) now describe the actual proprietary DM construction — kind 1059 gift wrap carrying XChaCha20-Poly1305 with a 24-byte nonce, base64url v2: framing, and an HKDF that borrows the nip44-v2 info label but is not the NIP-44 key schedule — instead of claiming NIP-17/44/59. Hardens the existing legacy inbound path: 64 KiB ciphertext cap before decode (~46x the largest producible legacy envelope), outer kind/recipient-tag/signature binding, tagless kind-13 seal binding, unsigned kind-14 inner binding, inner tags restricted to the two shapes deployed clients emit (verified against every historical iOS release and a fixture frozen from Android production), SecRandomCopyBytes failure now throws, non-UTF-8 plaintext now throws instead of returning empty. Adds frozen cross-platform fixtures with hash-pinned generators; interop-reviewed with no rejection surface for deployed clients.