commit 2c1d626b9f86a72c41f2b0768aa3e127cb7e4cb0 Author: Mike Perry mikeperry-git@torproject.org Date: Mon Jul 6 11:32:05 2020 -0500
Document relay commands for circpad cells. --- padding-spec.txt | 11 ++++++++--- tor-spec.txt | 2 ++ 2 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/padding-spec.txt b/padding-spec.txt index b9d99b7..f6356ed 100644 --- a/padding-spec.txt +++ b/padding-spec.txt @@ -309,8 +309,12 @@ the anonymity and load-balancing implications of their choices.
Because circuit padding machines only become active at certain points in circuit lifetime, and because more than one padding machine may be active at - any given point in circuit lifetime, there is also a padding negotiation cell, - with fields as follows: + any given point in circuit lifetime, there is also a padding negotiation + cell and a negotiated response. These are relay commands 41 and 42, with + relay headers as per section 6.1 of tor-spec.txt. + + The fields of the relay cell Data payload of a negotiate request are + as follows:
const CIRCPAD_COMMAND_STOP = 1; const CIRCPAD_COMMAND_START = 2; @@ -341,7 +345,8 @@ the anonymity and load-balancing implications of their choices.
When a relay receives a circpad_negotiate cell, it checks that it supports the requested machine, and sends a circpad_negotiated cell, which is formatted - as follows: + in the data payload of a relay cell with command number 42 (see tor-spec.txt + section 6.1), as follows:
struct circpad_negotiated { u8 version IN [0]; diff --git a/tor-spec.txt b/tor-spec.txt index 40ea4cc..af16fa4 100644 --- a/tor-spec.txt +++ b/tor-spec.txt @@ -1596,6 +1596,8 @@ see tor-design.pdf.
32..40 -- Used for hidden services; see rend-spec-{v2,v3}.txt.
+ 41..42 -- Used for circuit padding; see Section 3 of padding-spec.txt. + Commands labelled as "forward" must only be sent by the originator of the circuit. Commands labelled as "backward" must only be sent by other nodes in the circuit back to the originator. Commands marked