Skip to content

GitLab

  • Projects
  • Groups
  • Snippets
  • Help
    • Loading...
  • Help
    • Help
    • Support
    • Community forum
    • Submit feedback
    • Contribute to GitLab
  • Sign in
Trac
Trac
  • Project overview
    • Project overview
    • Details
    • Activity
  • Issues 246
    • Issues 246
    • List
    • Boards
    • Labels
    • Service Desk
    • Milestones
  • Operations
    • Operations
    • Metrics
    • Incidents
  • Analytics
    • Analytics
    • Value Stream
  • Wiki
    • Wiki
  • Members
    • Members
  • Activity
  • Create a new issue
  • Issue Boards
Collapse sidebar

GitLab is used only for code review, issue tracking and project management. Canonical locations for source code are still https://gitweb.torproject.org/ https://git.torproject.org/ and git-rw.torproject.org.

  • Legacy
  • TracTrac
  • Issues
  • #33545

Closed (moved)
Open
Opened Mar 06, 2020 by Mark Smith@mcs

assertion failure when "all zero" client auth key provided

While doing some Tor Browser testing for Sponsor 27, I experienced the following after I intentionally used an incorrect client auth key for a v3 onion service:

... [err] tor_assertion_failed_: Bug: src/feature/hs/hs_descriptor.c:1423: decrypt_descriptor_cookie: Assertion !fast_mem_is_zero((char *) client_auth_sk, sizeof(*client_auth_sk)) failed; aborting. (on Tor 0.4.4.0-alpha-dev 1da0b05a5cace6ed)

As it turns out, I happened to enter a key that is consists entirely of zero bits. This is an unusual thing to do, but I do not think tor should exit.

Steps to reproduce in Tor Browser:

  1. Try to load an http or https page for a v3 onion service that requires client authentication, e.g., dgoulet's test server.
  2. Enter 56 'A's when prompted for a client auth key.

Result: tor exits due to the assertion failure. Behind the scenes, the browser installs the key via a control port command like the following:

onion_client_auth_add <onion-addr> x25519:AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=

and then tries to access the onion service again (page reload).

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information
Assignee
Assign to
Tor: 0.4.3.x-final
Milestone
Tor: 0.4.3.x-final
Assign milestone
Time tracking
None
Due date
None
Reference: legacy/trac#33545