Skip to content
GitLab
Projects Groups Snippets
  • /
  • Help
    • Help
    • Support
    • Community forum
    • Submit feedback
    • Contribute to GitLab
  • Sign in
  • Trac Trac
  • Project information
    • Project information
    • Activity
    • Labels
    • Members
  • Issues 246
    • Issues 246
    • List
    • Boards
    • Service Desk
    • Milestones
  • Monitor
    • Monitor
    • Metrics
    • Incidents
  • Analytics
    • Analytics
    • Value stream
  • Wiki
    • Wiki
  • Activity
  • Create a new issue
  • Issue Boards
Collapse sidebar
  • Legacy
  • TracTrac
  • Issues
  • #26860
Closed (moved) (moved)
Open
Issue created Jul 18, 2018 by dmr@dmr

Spec: decryption order appears to be wrongly specified

catalyst noted in #tor-dev that the decryption algorithm in 5.5:

  • won't work unless decryption is commutative (which it is for plain AES-CTR, but not for the proposal)
  • doesn't look like it'll work to handle a relay cell arriving at the OP that originates from an intermediate node

I had also noted the latter, so I postulated is the order of that line backwards? that is... should it be "For I=1...N?" and asked what does little-t tor do?

And asn noted:

in relay_decrypt_cell() it does: {{{ if (CIRCUIT_IS_ORIGIN(circ)) { /* We're at the beginning of the circuit. * We'll want to do layered decrypts. */ crypt_path_t *thishop, *cpath = TO_ORIGIN_CIRCUIT(circ)->cpath; thishop = cpath; }}} i think this is I=1...N like you say (for 1 being the hop closest to the OP)

So it looks like this is an error in the spec, rather than a problem with tor.

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information
Assignee
Assign to
Time tracking