cpabe: Serializing ciphertext with 32-bit prefixes. #490
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bwesterb
approved these changes
Mar 20, 2024
Notice about ciphertext change and testing format. Previously, tkn20 ciphertext was encoding the ciphertext header `C1`, the envelope `env` (containing inner ciphertext), and macData using 16-bit prefixes, which caused a limitation on the maximum size allowed for encrypting plaintexts. With this change, the encoding now uses 32-bit prefixes for these three elements allowing to encrypt plaintexts longer than 2^16 bytes. So, ciphertexts produced by tkn20 package are now 12 bytes longer. Ciphertexts in the previous format are still decryptable. The following functions are backwards-compatible: - AttributeKey.Decrypt - Attributes.CouldDecrypt - Policy.ExtractFromCiphertext
bwesterb
approved these changes
Apr 16, 2024
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Serializing ciphertext with 32-bit prefixes.
Previously, tkn20 ciphertext was encoding the ciphertext header
C1, the envelopeenv(containing inner ciphertext), andmacDatausing 16-bit prefixes, which caused a limitation on the maximum size allowed for encrypting plaintexts.With this change, the encoding now uses 32-bit prefixes for these three elements allowing to encrypt plaintexts longer than 2^16 bytes. So, ciphertexts produced by tkn20 package are now 12 bytes longer.
Changes are backwards compatible, meaning that ciphertexts in the previous format are still decryptable. The following functions are backwards-compatible:
- AttributeKey.Decrypt
- Attributes.CouldDecrypt
- Policy.ExtractFromCiphertext
Note: Since the format of ciphertexts is changed, we need to release a version, once this gets merged.
Fixes #484