JWE
JSON Web Encryption
RFC7516
JSONを暗号化・複合化するための仕様
実装
Node
https://github.com/panva/jose
algにECDHを使いたい時は https://github.com/panva/jose-x25519-ecdh が必要
Node 12以降が必要なので Cloud Functions では現在使えないので注意
Go
https://godoc.org/gopkg.in/square/go-jose.v2
JWE Compact Serialization
以下の部分からなる (各部分はURL-encoded)
JWE Protected Header
JSON object that contains the Header Parameters that are integrity
protected by the authenticated encryption operation. These
parameters apply to all recipients of the JWE. For the JWE
Compact Serialization, this comprises the entire JOSE Header. For
the JWE JSON Serialization, this is one component of the JOSE
Header.
JWE Encrypted Key
JWE Initialization Vector
9. Generate a random JWE Initialization Vector of the correct size
for the content encryption algorithm (if required for the
algorithm); otherwise, let the JWE Initialization Vector be the
empty octet sequence.
これがあるので同じペイロードやキーを与えても実行する度に値は変わる
JWE Ciphertext
JWE Authentication Tag