1. About these specifications
  3. Introduction
  4. A short introduction to Tor
    1. Notation and conventions
  7. The core Tor protocol
  8. Tor Protocol Specification
    1. Preliminaries
    2. Relay keys and identities
    3. Channels
      1. Negotiating and initializing channels
        1. Obsolete channel negotiation handshakes
      3. Cells (messages on channels)
    5. Circuit management
      1. Create and Created cells
      2. Setting circuit keys
      3. Creating circuits
      4. Tearing down circuits
      5. Routing relay cells
      6. Handling relay_early cells
    7. Application connections and stream management
      1. Relay cells
      2. Opening streams and transferring data
      3. Closing streams
      4. Remote hostname lookup
    9. Flow control
    10. Subprotocol versioning
    11. Certificates in Tor
  10. Tor directory protocol, version 3
    1. Outline
    2. netdoc document meta-format
    3. Router operation and formats
      1. Uploading server descriptors and extra-info documents
      2. Server descriptor format
      3. Extra-info document format
      4. Nonterminals in server descriptors
    5. Directory authority operation and formats
      1. Creating key certificates
      2. Accepting server descriptor and extra-info document uploads
      3. Computing microdescriptors
      4. Exchanging votes
        1. Vote and consensus status document formats
        2. Assigning flags in a vote
        3. Serving bandwidth list files
      6. Downloading information from other directory authorities
      7. Computing a consensus from a set of votes
      8. Exchanging detached signatures
      9. Publishing the signed consensus
    7. Directory cache operation
    8. Client operation
    9. Standards compliance
    10. Consensus-negotiation timeline.
    11. General-use HTTP URLs
    12. Converting a curve25519 public key to an ed25519 public key
    13. Inferring missing proto lines.
    14. Limited ed diff format
    15. Tor Shared Random Subsystem Specification
      1. Introduction
      2. Overview
      3. Protocol
      4. Specification [SPEC]
      5. Security Analysis
      6. Discussion
      7. Acknowledgements
  12. Tor Path Specification
    1. General operation
    2. Building circuits
      1. When we build
      2. Path selection and constraints
      3. Cannibalizing circuits
      4. Learning when to give up ("timeout") on circuit construction
      5. Handling failure
    4. Attaching streams to circuits
    5. Hidden-service related circuits
    6. Guard nodes
    7. Server descriptor purposes
    8. Detecting route manipulation by Guard nodes (Path Bias)
  14. Tor Guard Specification
    1. State instances
    2. Circuit Creation, Entry Guard Selection (1000 foot view)
    3. The algorithm.
    4. Appendices
  16. Tor Vanguards Specification
    1. Full Vanguards
    2. Vanguards-Lite
    3. Path Construction
    4. Statistical Analysis
  18. Tor Padding Specification
    1. Overview
    2. Connection-level padding
    3. Circuit-level padding
    4. Acknowledgments
  20. Preventing Denial-Of-Service
    1. Overview
    2. Memory exhaustion
  23. Additional behaviors for clients
  24. Tor's extensions to the SOCKS protocol
  25. Special Hostnames in Tor
  27. Onion services
  28. Tor Rendezvous Specification - Version 3
    1. Hidden services: overview and preliminaries.
    2. Protocol overview
    3. Generating and publishing hidden service descriptors [HSDIR]
      1. Deriving blinded keys and subcredentials [SUBCRED]
      2. Publishing shared random values [PUB-SHAREDRANDOM]
      3. Hidden service descriptors: outer wrapper [DESC-OUTER]
      4. Hidden service descriptors: encryption format [HS-DESC-ENC]
    5. The introduction protocol [INTRO-PROTOCOL]
    6. The rendezvous protocol
    7. Encrypting data between client and host
    8. Encoding onion addresses [ONIONADDRESS]
    9. Managing streams
    10. References
    11. Appendix A: Signature scheme with key blinding [KEYBLIND]
    12. Appendix B: Selecting nodes [PICKNODES]
    13. Appendix C: Recommendations for searching for vanity .onions [VANITY]
    14. Appendix D: (removed)
    15. Appendix E: Reserved numbers
    16. Appendix F: Hidden service directory format [HIDSERVDIR-FORMAT]
    17. Appendix G: Managing restricted discovery data [RESTRICTED-DISCOVERY-MGMT]
    18. Appendix F: Two methods for managing revision counters.
    19. Appendix G: Test vectors
  30. Proof of Work for onion service introduction
    1. Motivation
    2. Common protocol
    3. Version 1, Equi-X and Blake2b
    4. Analysis and discussion
  33. Anticensorship tools and protocols
  34. Extended ORPort for pluggable transports
  35. Pluggable Transport Specification (Version 1)
    1. Introduction
    2. Architecture Overview
    3. Specification
      1. Pluggable Transport Naming
      2. Pluggable Transport Configuration Environment Variables
      3. Pluggable Transport To Parent Process Communication
      4. Pluggable Transport Shutdown
      5. Pluggable Transport Client Per-Connection Arguments
    5. Anonymity Considerations
    6. References
    7. Acknowledgments
    8. Appendix A: Example Client Pluggable Transport Session
    9. Appendix B: Example Server Pluggable Transport Session
  38. For C Tor only
  39. The Tor Control Protocol
    1. Protocol outline
    2. Message format
    3. Commands
    4. Replies
    5. Implementation notes
  41. How Tor Version Numbers Work
  43. Less commonly needed file formats
  44. Tor Bandwidth File Format
    1. Scope and preliminaries
    2. Format details
      1. Definitions
      2. Header List format
      3. Relay Line format
      4. Implementation details
    4. Sample data
    5. Scaling bandwidths
  47. Implementation details
  48. Tor Directory List Format
  50. Reserved names and numbers
  51. Tor network parameters
  52. SSH protocol extensions
  54. Unfinished
  55. Glossary
  57. Historical information
  58. Historical protocol elements and behaviours
    1. Historical netdoc Items
    2. Historical special hostnames
  60. BridgeDB specification
  62. Maintenance and and editing of the Tor Specifications
  63. About the Tor Specifications documents
  64. Style guide
  65. Permalinks