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commit 7b3d7a40a0ac8f59b9f6d79205dfc53de4168f0c Author: Ian Jackson ijackson@chiark.greenend.org.uk AuthorDate: Mon Feb 6 12:51:41 2023 +0000
Use proper names for KP_hsc_desc_enc --- rend-spec-v3.txt | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/rend-spec-v3.txt b/rend-spec-v3.txt index afc2a46..805e0d9 100644 --- a/rend-spec-v3.txt +++ b/rend-spec-v3.txt @@ -1231,19 +1231,17 @@ Table of contents:
When client authorization is enabled, each "auth-client" line contains the descriptor cookie encrypted to each individual client. We assume that - each authorized client possesses a pre-shared x25519 keypair which is - used to decrypt the descriptor cookie. + each authorized client possesses a pre-shared x25519 keypair + KS/KP_hsc_desc_enc which is used to decrypt the descriptor cookie.
We now describe the descriptor cookie encryption scheme. Here are the relevant keys:
- client_x = private x25519 key of authorized client - client_X = public x25519 key of authorized client descriptor_cookie = descriptor cookie used to encrypt the descriptor
And here is what the hidden service computes:
- SECRET_SEED = x25519(KS_hs_desc_ephem, client_X) + SECRET_SEED = x25519(KS_hs_desc_ephem, KP_hsc_desc_enc) KEYS = KDF(N_hs_subcred | SECRET_SEED, 40) CLIENT-ID = fist 8 bytes of KEYS COOKIE-KEY = last 32 bytes of KEYS