Network Status Documents¶
Parsing for Tor network status documents. This supports both the v2 and v3 dir-spec. Documents can be obtained from a few sources...
- The 'cached-consensus' file in Tor's data directory.
- Archived descriptors provided by CollecTor.
- Directory authorities and mirrors via their DirPort.
... and contain the following sections...
- document header
- list of
stem.descriptor.networkstatus.DirectoryAuthority
- list of
stem.descriptor.router_status_entry.RouterStatusEntry
- document footer
For a great graphical overview see Jordan Wright's chart describing the anatomy of the consensus.
Of these, the router status entry section can be quite large (on the order of
hundreds of kilobytes). As such we provide a couple of methods for reading
network status documents through parse_file()
.
For more information see DocumentHandler()
...
from stem.descriptor import parse_file, DocumentHandler
with open('.tor/cached-consensus', 'rb') as consensus_file:
# Processes the routers as we read them in. The routers refer to a document
# with an unset 'routers' attribute.
for router in parse_file(consensus_file, 'network-status-consensus-3 1.0', document_handler = DocumentHandler.ENTRIES):
print router.nickname
Module Overview:
NetworkStatusDocument - Network status document
|- NetworkStatusDocumentV2 - Version 2 network status document
|- NetworkStatusDocumentV3 - Version 3 network status document
+- BridgeNetworkStatusDocument - Version 3 network status document for bridges
KeyCertificate - Certificate used to authenticate an authority
DocumentSignature - Signature of a document by a directory authority
DirectoryAuthority - Directory authority as defined in a v3 network status document
-
class
stem.descriptor.networkstatus.
PackageVersion
[source]¶ Bases:
stem.descriptor.networkstatus.PackageVersion
Latest recommended version of a package that's available.
Variables: - name (str) -- name of the package
- version (str) -- latest recommended version
- url (str) -- package's url
- digests (dict) -- mapping of digest types to their value
Bases:
stem.descriptor.networkstatus.SharedRandomnessCommitment
Directory authority's commitment for generating the next shared random value.
Variables: - version (int) -- shared randomness protocol version
- algorithm (str) -- hash algorithm used to make the commitment
- identity (str) -- authority's sha1 identity fingerprint
- commit (str) -- base64 encoded commitment hash to the shared random value
- reveal (str) -- base64 encoded commitment to the shared random value, None of not provided
-
class
stem.descriptor.networkstatus.
NetworkStatusDocument
(contents, lazy_load=False)[source]¶ Bases:
stem.descriptor.Descriptor
Common parent for network status documents.
-
class
stem.descriptor.networkstatus.
NetworkStatusDocumentV2
(raw_content, validate=False)[source]¶ Bases:
stem.descriptor.networkstatus.NetworkStatusDocument
Version 2 network status document. These have been deprecated and are no longer generated by Tor.
Variables: - routers (dict) -- fingerprints to
RouterStatusEntryV2
contained in the document - version (int) -- * document version
- hostname (str) -- * hostname of the authority
- address (str) -- * authority's IP address
- dir_port (int) -- * authority's DirPort
- fingerprint (str) -- * authority's fingerprint
- contact (str) -- * authority's contact information
- signing_key (str) -- * authority's public signing key
- client_versions (list) -- list of recommended client tor version strings
- server_versions (list) -- list of recommended server tor version strings
- published (datetime) -- * time when the document was published
- options (list) -- * list of things that this authority decides
- signing_authority (str) -- * name of the authority signing the document
- signature (str) -- * authority's signature for the document
* attribute is either required when we're parsed with validation or has a default value, others are left as None if undefined
- routers (dict) -- fingerprints to
-
class
stem.descriptor.networkstatus.
NetworkStatusDocumentV3
(raw_content, validate=False, default_params=True)[source]¶ Bases:
stem.descriptor.networkstatus.NetworkStatusDocument
Version 3 network status document. This could be either a vote or consensus.
Variables: - routers (dict) -- fingerprint to
RouterStatusEntryV3
mapping for relays contained in the document - version (int) -- * document version
- version_flavor (str) -- * flavor associated with the document (such as 'microdesc')
- is_consensus (bool) -- * True if the document is a consensus
- is_vote (bool) -- * True if the document is a vote
- is_microdescriptor (bool) -- * True if this is a microdescriptor flavored document, False otherwise
- valid_after (datetime) -- * time when the consensus became valid
- fresh_until (datetime) -- * time when the next consensus should be produced
- valid_until (datetime) -- * time when this consensus becomes obsolete
- vote_delay (int) -- * number of seconds allowed for collecting votes from all authorities
- dist_delay (int) -- * number of seconds allowed for collecting signatures from all authorities
- client_versions (list) -- list of recommended client tor versions
- server_versions (list) -- list of recommended server tor versions
- packages (list) -- * list of
PackageVersion
entries - known_flags (list) -- * list of
Flag
for the router's flags - params (dict) -- * dict of parameter(str) => value(int) mappings
- directory_authorities (list) -- * list of
DirectoryAuthority
objects that have generated this document - signatures (list) -- *
DocumentSignature
of the authorities that have signed the document
Consensus Attributes:
Variables: - consensus_method (int) -- method version used to generate this consensus
- bandwidth_weights (dict) -- dict of weight(str) => value(int) mappings
- shared_randomness_current_value (str) -- base64 encoded current shared random value
- shared_randomness_previous_value (str) -- base64 encoded last shared random value
Vote Attributes:
Variables: - consensus_methods (list) -- list of ints for the supported method versions
- published (datetime) -- time when the document was published
- flag_thresholds (dict) -- * mapping of internal performance thresholds used while making the vote, values are ints or floats
- recommended_client_protocols (dict) -- recommended protocols for clients
- recommended_relay_protocols (dict) -- recommended protocols for relays
- required_client_protocols (dict) -- required protocols for clients
- required_relay_protocols (dict) -- required protocols for relays
* attribute is either required when we're parsed with validation or has a default value, others are left as None if undefined
Changed in version 1.4.0: Added the packages attribute.
Changed in version 1.5.0: Added the is_shared_randomness_participate, shared_randomness_commitments, shared_randomness_previous_reveal_count, shared_randomness_previous_value, shared_randomness_current_reveal_count, and shared_randomness_current_value attributes.
Changed in version 1.6.0: Added the recommended_client_protocols, recommended_relay_protocols, required_client_protocols, and required_relay_protocols.
Changed in version 1.6.0: The shared randomness attributes were misdocumented in the tor spec and as such never set. They're now an attribute of directory_authorities.
-
HEADER_PARSER_FOR_LINE
= {'client-versions': <function _parse at 0xf60543ac>, 'consensus-method': <function _parse_header_consensus_method_line at 0xf605409c>, 'consensus-methods': <function _parse_header_consensus_methods_line at 0xf6054064>, 'flag-thresholds': <function _parse_header_flag_thresholds_line at 0xf6054144>, 'fresh-until': <function _parse at 0xf605433c>, 'known-flags': <function _parse at 0xf6054454>, 'network-status-version': <function _parse_header_network_status_version_line at 0xf6097f0c>, 'package': <function _parse_package_line at 0xf6054224>, 'params': <function _parse_header_parameters_line at 0xf605417c>, 'published': <function _parse at 0xf6097e2c>, 'recommended-client-protocols': <function _parse at 0xf6054534>, 'recommended-relay-protocols': <function _parse at 0xf605456c>, 'required-client-protocols': <function _parse at 0xf60545a4>, 'required-relay-protocols': <function _parse at 0xf60545dc>, 'server-versions': <function _parse at 0xf60543e4>, 'shared-rand-current-value': <function _parse_shared_rand_current_value at 0xf60542cc>, 'shared-rand-previous-value': <function _parse_shared_rand_previous_value at 0xf6054294>, 'valid-after': <function _parse at 0xf6054304>, 'valid-until': <function _parse at 0xf6054374>, 'vote-status': <function _parse_header_vote_status_line at 0xf605402c>, 'voting-delay': <function _parse_header_voting_delay_line at 0xf60540d4>}¶
-
FOOTER_PARSER_FOR_LINE
= {'bandwidth-weights': <function _parse at 0xf60544c4>, 'directory-footer': <function _parse_directory_footer_line at 0xf60541b4>, 'directory-signature': <function _parse_footer_directory_signature_line at 0xf60541ec>}¶
-
classmethod
create
(attr=None, exclude=(), validate=True, sign=False, authorities=None, routers=None)[source]¶
-
validate_signatures
(key_certs)[source]¶ Validates we're properly signed by the signing certificates.
New in version 1.6.0.
Parameters: key_certs (list) -- KeyCertificates
to validate the consensus againstRaises: ValueError if an insufficient number of valid signatures are present.
-
meets_consensus_method
(method)[source]¶ Checks if we meet the given consensus-method. This works for both votes and consensuses, checking our 'consensus-method' and 'consensus-methods' entries.
Parameters: method (int) -- consensus-method to check for Returns: True if we meet the given consensus-method, and False otherwise
- routers (dict) -- fingerprint to
-
class
stem.descriptor.networkstatus.
DirectoryAuthority
(raw_content, validate=False, is_vote=False)[source]¶ Bases:
stem.descriptor.Descriptor
Directory authority information obtained from a v3 network status document.
Authorities can optionally use a legacy format. These are no longer found in practice, but have the following differences...
- The authority's nickname ends with '-legacy'.
- There's no contact or vote_digest attribute.
Variables: - nickname (str) -- * authority's nickname
- v3ident (str) -- * identity key fingerprint used to sign votes and consensus
- hostname (str) -- * hostname of the authority
- address (str) -- * authority's IP address
- dir_port (int) -- * authority's DirPort
- or_port (int) -- * authority's ORPort
- is_legacy (bool) -- * if the authority's using the legacy format
- contact (str) -- contact information, this is included if is_legacy is False
Consensus Attributes:
Variables: vote_digest (str) -- digest of the authority that contributed to the consensus, this is included if is_legacy is False Vote Attributes:
Variables: - legacy_dir_key (str) -- fingerprint of and obsolete identity key
- key_certificate (stem.descriptor.networkstatus.KeyCertificate) -- * authority's key certificate
- is_shared_randomness_participate (bool) -- * True if this authority participates in establishing a shared random value, False otherwise
- shared_randomness_commitments (list) -- * list of
SharedRandomnessCommitment
entries - shared_randomness_previous_reveal_count (int) -- number of commitments used to generate the last shared random value
- shared_randomness_previous_value (str) -- base64 encoded last shared random value
- shared_randomness_current_reveal_count (int) -- number of commitments used to generate the current shared random value
- shared_randomness_current_value (str) -- base64 encoded current shared random value
* mandatory attribute
Changed in version 1.4.0: Renamed our 'fingerprint' attribute to 'v3ident' (prior attribute exists for backward compatability, but is deprecated).
Changed in version 1.6.0: Added the is_shared_randomness_participate, shared_randomness_commitments, shared_randomness_previous_reveal_count, shared_randomness_previous_value, shared_randomness_current_reveal_count, and shared_randomness_current_value attributes.
-
class
stem.descriptor.networkstatus.
KeyCertificate
(raw_content, validate=False)[source]¶ Bases:
stem.descriptor.Descriptor
Directory key certificate for a v3 network status document.
Variables: - version (int) -- * version of the key certificate
- address (str) -- authority's IP address
- dir_port (int) -- authority's DirPort
- fingerprint (str) -- * authority's fingerprint
- identity_key (str) -- * long term authority identity key
- published (datetime) -- * time when this key was generated
- expires (datetime) -- * time after which this key becomes invalid
- signing_key (str) -- * directory server's public signing key
- crosscert (str) -- signature made using certificate's signing key
- certification (str) -- * signature of this key certificate signed with the identity key
* mandatory attribute
-
class
stem.descriptor.networkstatus.
DocumentSignature
(method, identity, key_digest, signature, validate=False)[source]¶ Bases:
object
Directory signature of a v3 network status document.
Variables: - method (str) -- algorithm used to make the signature
- identity (str) -- fingerprint of the authority that made the signature
- key_digest (str) -- digest of the signing key
- signature (str) -- document signature
Parameters: validate (bool) -- checks validity if True
Raises: ValueError if a validity check fails
-
class
stem.descriptor.networkstatus.
BridgeNetworkStatusDocument
(raw_content, validate=False)[source]¶ Bases:
stem.descriptor.networkstatus.NetworkStatusDocument
Network status document containing bridges. This is only available through the metrics site.
Variables: - routers (dict) -- fingerprint to
RouterStatusEntryV3
mapping for relays contained in the document - published (datetime) -- time when the document was published
- routers (dict) -- fingerprint to