[][src]Struct sequoia_openpgp::packet::signature::subpacket::Subpacket

pub struct Subpacket { /* fields omitted */ }

Signature subpackets.

Most of a signature's attributes are not stored in fixed fields, but in so-called subpackets. These subpackets are stored in a Signature's so-called subpacket areas, which are effectively small key-value stores. The keys are subpacket tags (SubpacketTag). The values are well-structured (SubpacketValue).

In addition to their key and value, subpackets also include a critical flag. When set, this flag indicates to the OpenPGP implementation that if it doesn't understand the subpacket, it must consider the signature to be invalid. (Likewise, if it isn't set, then it means that it is safe for the implementation to ignore the subpacket.) This enables forward compatibility with security-relevant extensions.

It is possible to control how Sequoia's higher-level functionality handles unknown, critical subpackets using a Policy object. Depending on the degree of control required, it may be sufficient to customize a StandardPolicy object using, for instance, the StandardPolicy::accept_critical_subpacket method.

The subpacket system is extensible in two ways. First, although limited, the subpacket name space is not exhausted. So, it is possible to introduce new packets. Second, one of the subpackets, the Notation Data subpacket (NotationData), is explicitly designed for adding arbitrary data to signatures.

Subpackets are described in Section of RFC 4880.


impl Subpacket[src]

pub fn new(value: SubpacketValue, critical: bool) -> Result<Subpacket>[src]

Creates a new Subpacket.

pub fn critical(&self) -> bool[src]

Returns whether the critical bit is set.

pub fn tag(&self) -> SubpacketTag[src]

Returns the Subpacket's tag.

pub fn value(&self) -> &SubpacketValue[src]

Returns the Subpacket's value.

pub fn authenticated(&self) -> bool[src]

Returns whether the information in this subpacket has been authenticated.

There are three ways a subpacket can be authenticated:

  • It is in the hashed subpacket area and the signature has been verified.
  • It is in the unhashed subpacket area and the information is self-authenticating and has been authenticated by Sequoia. This is can be done for issuer information and embedded Signatures.
  • The subpacket has been authenticated by the user and marked as such using Subpacket::set_authenticated.

Note: The authentication is only valid in the context of the signature the subpacket is in. If the Subpacket is cloned, or a Subpacket is added to a SubpacketArea, the flag is cleared.

pub fn set_authenticated(&mut self, authenticated: bool) -> bool[src]

Marks the information in this subpacket as authenticated or not.

See Subpacket::authenticated for more information.

Trait Implementations

impl Clone for Subpacket[src]

impl Debug for Subpacket[src]

impl Eq for Subpacket[src]

impl Hash for Subpacket[src]

impl Marshal for Subpacket[src]

impl MarshalInto for Subpacket[src]

impl Ord for Subpacket[src]

impl PartialEq<Subpacket> for Subpacket[src]

impl PartialOrd<Subpacket> for Subpacket[src]

Auto Trait Implementations

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impl<T> From<T> for T[src]

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