From 112871b61843480f5e80612bcdada4c9aa5aed26 Mon Sep 17 00:00:00 2001 From: Nick Mathewson Date: Tue, 30 Mar 2004 19:20:11 +0000 Subject: [PATCH] Make service IDs 80 bits, not 128 svn:r1393 --- rend-spec.txt | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/rend-spec.txt b/rend-spec.txt index afe7d87..0130d49 100644 --- a/rend-spec.txt +++ b/rend-spec.txt @@ -171,16 +171,15 @@ Tor Rendezvous Spec ~16-octet hash of Bob's service's public key, computed as follows: 1. Let H = H(PK). - 2. Let H' = the first 130 bits of H, considering each octet from + 2. Let H' = the first 80 bits of H, considering each octet from most significant bit to least significant big. 2. Generate a 26-character encoding of H', taking H' 5 bits at a time, and mapping each 5-bit value to a character as follows: 0..25 map to the characters 'a'...'z', respectively. 26..31 map to the characters '0'...'5', respectively. - (We only use 130 bits instead of the 160 bits from SHA1 because we don't - need to worry about man-in-the-middle attacks. We use 130 instead of 128 - in order to have an even multiple of 5.) + (We only use 80 bits instead of the 160 bits from SHA1 because we don't + need to worry about man-in-the-middle attacks.) [Yes, numbers are allowed at the beginning. See RFC1123. -NM]