📅 Original date posted:2016-06-27
📝 Original message:To quote:
> HMAC_SHA512(key=ecdh_secret|cipher-type,msg="encryption key").
>
> K_1 must be the left 32bytes of the HMAC_SHA512 hash.
> K_2 must be the right 32bytes of the HMAC_SHA512 hash.
This seems a weak reason to introduce SHA512 to the mix. Can we just
make:
K_1 = HMAC_SHA256(key=ecdh_secret|cipher-type,msg="header encryption key")
K_2 = HMAC_SHA256(key=ecdh_secret|cipher-type,msg="body encryption key")
Thanks,
Rusty.
Rusty Russell [ARCHIVE] /
npub1zw…hkhpx
2023-06-07 17:51:32
in reply to nevent1q…2yuz
Author Public Key
npub1zw7cc8z78v6s3grujfvcv3ckpvg6kr0w7nz9yzvwyglyg0qu5sjsqhkhpxPublished at
2023-06-07 17:51:32Event JSON
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"content": "📅 Original date posted:2016-06-27\n📝 Original message:To quote:\n\n\u003e HMAC_SHA512(key=ecdh_secret|cipher-type,msg=\"encryption key\").\n\u003e \n\u003e K_1 must be the left 32bytes of the HMAC_SHA512 hash.\n\u003e K_2 must be the right 32bytes of the HMAC_SHA512 hash.\n\nThis seems a weak reason to introduce SHA512 to the mix. Can we just\nmake:\n\nK_1 = HMAC_SHA256(key=ecdh_secret|cipher-type,msg=\"header encryption key\")\nK_2 = HMAC_SHA256(key=ecdh_secret|cipher-type,msg=\"body encryption key\")\n\nThanks,\nRusty.",
"sig": "071f7146c52b63cb996919272522e8d2981c8b76f4e965252768079b3fda80997ac139ee19608de46bac0fd32d95727b394bf1d0a8c201a17389ccdb63e7afc5"
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