Struct Versions

pub struct Versions { /* private fields */ }

A Versions message begins channel negotiation.

Every channel must begin by sending a Versions message. This message lists the link protocol versions that this Tor implementation supports.

Note that we should never actually send Versions cells using the usual channel cell encoding: Versions cells always use two-byte circuit IDs, whereas all the other cell types use four-byte circuit IDs [assuming a non-obsolete version is negotiated].

Implementations

impl Versions

pub fn new<B>(vs: B) -> Result<Self>

where B: Into<Vec<u16>>,

Construct a new Versions message using a provided list of link protocols.

Returns an error if the list of versions is too long.

pub fn encode_for_handshake(self) -> EncodeResult<Vec<u8>>

Encode this VERSIONS cell in the manner expected for a handshake.

(That’s different from a standard cell encoding, since we have not negotiated versions yet, and so our circuit-ID length is an obsolete 2 bytes).

pub fn best_shared_link_protocol(&self, my_protos: &[u16]) -> Option<u16>

Return the best (numerically highest) link protocol that is shared by this versions cell and my_protos.

Trait Implementations

impl Body for Versions

fn encode_onto<W: Writer + ?Sized>(self, w: &mut W) -> EncodeResult<()>

Consume this message and encode its body onto w.

fn decode_from_reader(r: &mut Reader<'_>) -> Result<Self>

Decode a channel cell body from a provided reader.

impl ChanMsg for Versions

fn cmd(&self) -> ChanCmd

Return the ChanCmd for this message.

fn encode_onto<W: Writer + ?Sized>(self, w: &mut W) -> EncodeResult<()>

Write the body of this message (not including length or command).

fn decode_from_reader(cmd: ChanCmd, r: &mut Reader<'_>) -> Result<Self>

Decode this message from a given reader, according to a specified command value. The reader must be truncated to the exact length of the body.

impl Clone for Versions

fn clone(&self) -> Versions

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Versions

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<Versions> for AnyChanMsg

fn from(m: Versions) -> AnyChanMsg

Converts to this type from the input type.

impl From<Versions> for AnyChanCell

fn from(body: Versions) -> AnyChanCell

Converts to this type from the input type.

impl Readable for Versions

fn take_from(r: &mut Reader<'_>) -> Result<Self>

Try to extract an object of this type from a Reader.