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//! Keys, their associated signatures, and some useful methods. //! //! A [`KeyAmalgamation`] is similar to a [`ComponentAmalgamation`], //! but a `KeyAmalgamation` includes some additional functionality //! that is needed to correctly implement a [`Key`] component's //! semantics. In particular, unlike other components where the //! binding signature stores the component's meta-data, a Primary Key //! doesn't have a binding signature (it is the thing that other //! components are bound to!), and, as a consequence, the associated //! meta-data is stored elsewhere. //! //! Unfortunately, a primary Key's meta-data is usually not stored on //! a direct key signature, which would be convenient as it is located //! at the same place as a binding signature would be, but on the //! primary User ID's binding signature. This requires some //! acrobatics on the implementation side to realize the correct //! semantics. In particular, a `Key` needs to memorize its role //! (i.e., whether it is a primary key or a subkey) in order to know //! whether to consider its own self signatures or the primary User //! ID's self signatures when looking for its meta-data. //! //! Ideally, a `KeyAmalgamation`'s role would be encoded in its type. //! This increases safety, and reduces the run-time overhead. //! However, we want [`Cert::keys`] to return an iterator over all //! keys; we don't want the user to have to specially handle the //! primary key when that fact is not relevant. This means that //! `Cert::keys` has to erase the returned `Key`s' roles: all items in //! an iterator must have the same type. To support this, we have to //! keep track of a `KeyAmalgamation`'s role at run-time. //! //! But, just because we need to erase a `KeyAmalgamation`'s role to //! implement `Cert::keys` doesn't mean that we have to always erase //! it. To achieve this, we use three data types: //! [`PrimaryKeyAmalgamation`], [`SubordinateKeyAmalgamation`], and //! [`ErasedKeyAmalgamation`]. The first two encode the role //! information in their type, and the last one stores it at run time. //! We provide conversion functions to convert the static type //! information into dynamic type information, and vice versa. //! //! Note: `KeyBundle`s and `KeyAmalgamation`s have a notable //! difference: whereas a `KeyBundle`'s role is a marker, a //! `KeyAmalgamation`'s role determines its semantics. A consequence //! of this is that it is not possible to convert a //! `PrimaryKeyAmalgamation` into a `SubordinateAmalgamation`s, or //! vice versa even though we support changing a `KeyBundle`'s role: //! //! ``` //! # use std::convert::TryInto; //! # use sequoia_openpgp as openpgp; //! # use openpgp::cert::prelude::*; //! # use openpgp::packet::prelude::*; //! # let (cert, _) = CertBuilder::new() //! # .add_userid("Alice") //! # .add_signing_subkey() //! # .add_transport_encryption_subkey() //! # .generate().unwrap(); //! // This works: //! cert.primary_key().bundle().role_as_subordinate(); //! //! // But this doesn't: //! let ka: ErasedKeyAmalgamation<_> = cert.keys().nth(0).expect("primary key"); //! let ka: openpgp::Result<SubordinateKeyAmalgamation<key::PublicParts>> = ka.try_into(); //! assert!(ka.is_err()); //! ``` //! //! The use of the prefix `Erased` instead of `Unspecified` //! (cf. [`KeyRole::UnspecifiedRole`]) emphasizes this. //! //! # Selecting Keys //! //! It is essential to choose the right keys, and to make sure that //! they appropriate. Below, we present some guidelines for the most //! common situations. //! //! ## Encrypting and Signing Messages //! //! As a general rule of thumb, when encrypting or signing a message, //! you want to use keys that are alive, not revoked, and have the //! appropriate capabilities right now. For example, the following //! code shows how to find a key, which is appropriate for signing a //! message: //! //! ```rust //! # use sequoia_openpgp as openpgp; //! # use openpgp::Result; //! # use openpgp::cert::prelude::*; //! use openpgp::types::RevocationStatus; //! use sequoia_openpgp::policy::StandardPolicy; //! //! # fn main() { f().unwrap(); } //! # fn f() -> Result<()> { //! # let (cert, _) = //! # CertBuilder::general_purpose(None, Some("alice@example.org")) //! # .generate()?; //! # let mut i = 0; //! let p = &StandardPolicy::new(); //! //! let cert = cert.with_policy(p, None)?; //! //! if let RevocationStatus::Revoked(_) = cert.revocation_status() { //! // The certificate is revoked, don't use any keys from it. //! # unreachable!(); //! } else if let Err(_) = cert.alive() { //! // The certificate is not alive, don't use any keys from it. //! # unreachable!(); //! } else { //! for ka in cert.keys() { //! if let RevocationStatus::Revoked(_) = ka.revocation_status() { //! // The key is revoked. //! # unreachable!(); //! } else if let Err(_) = ka.alive() { //! // The key is not alive. //! # unreachable!(); //! } else if ! ka.for_signing() { //! // The key is not signing capable. //! } else { //! // Use it! //! # i += 1; //! } //! } //! } //! # assert_eq!(i, 1); //! # Ok(()) //! # } //! ``` //! //! ## Verifying a Message //! //! When verifying a message, you only want to use keys that were //! alive, not revoked, and signing capable *when the message was //! signed*. These are the keys that the signer would have used, and //! they reflect the signer's policy when they made the signature. //! (See the [`Policy` discussion] for an explanation.) //! //! For version 4 Signature packets, the `Signature Creation Time` //! subpacket indicates when the signature was allegedly created. For //! the purpose of finding the key to verify the signature, this time //! stamp should be trusted: if the key is authenticated and the //! signature is valid, then the time stamp is valid; if the signature //! is not valid, then forging the time stamp won't help an attacker. //! //! ```rust //! # use sequoia_openpgp as openpgp; //! # use openpgp::Result; //! # use openpgp::cert::prelude::*; //! use openpgp::types::RevocationStatus; //! use sequoia_openpgp::policy::StandardPolicy; //! //! # fn main() { f().unwrap(); } //! # fn f() -> Result<()> { //! let p = &StandardPolicy::new(); //! //! # let (cert, _) = //! # CertBuilder::general_purpose(None, Some("alice@example.org")) //! # .generate()?; //! # let timestamp = None; //! # let issuer = cert.fingerprint(); //! # let mut i = 0; //! let cert = cert.with_policy(p, timestamp)?; //! if let RevocationStatus::Revoked(_) = cert.revocation_status() { //! // The certificate is revoked, don't use any keys from it. //! # unreachable!(); //! } else if let Err(_) = cert.alive() { //! // The certificate is not alive, don't use any keys from it. //! # unreachable!(); //! } else { //! for ka in cert.keys().key_handle(issuer) { //! if let RevocationStatus::Revoked(_) = ka.revocation_status() { //! // The key is revoked, don't use it! //! # unreachable!(); //! } else if let Err(_) = ka.alive() { //! // The key was not alive when the signature was made! //! // Something fishy is going on. //! # unreachable!(); //! } else if ! ka.for_signing() { //! // The key was not signing capable! Better be safe //! // than sorry. //! # unreachable!(); //! } else { //! // Try verifying the message with this key. //! # i += 1; //! } //! } //! } //! # assert_eq!(i, 1); //! # Ok(()) //! # } //! ``` //! //! ## Decrypting a Message //! //! When decrypting a message, it seems like one ought to only keys //! that were alive, not revoked, and encryption-capable when the //! message was encrypted. Unfortunately, we don't know when a //! message was encrypted. But anyway, due to the slow propagation of //! revocation certificates, we can't assume that senders won't //! mistakenly use a revoked key. //! //! However, wanting to decrypt a message encrypted using an expired //! or revoked key is reasonable. If someone is trying to decrypt a //! message using an expired key, then they are the certificate //! holder, and probably attempting to access archived data using a //! key that they themselves revoked! We don't want to prevent that. //! //! We do, however, want to check whether a key is really encryption //! capable. [This discussion] explains why using a signing key to //! decrypt a message can be dangerous. Since we need a binding //! signature to determine this, but we don't have the time that the //! message was encrypted, we need a workaround. One approach would //! be to check whether the key is encryption capable now. Since a //! key's key flags don't typically change, this will correctly filter //! out keys that are not encryption capable. But, it will skip keys //! whose self signature has expired. But that is not a problem //! either: no one sets self signatures to expire; if anything, they //! set keys to expire. Thus, this will not result in incorrectly //! failing to decrypt messages in practice, and is a reasonable //! approach. //! //! ```rust //! # use sequoia_openpgp as openpgp; //! # use openpgp::Result; //! # use openpgp::cert::prelude::*; //! use sequoia_openpgp::policy::StandardPolicy; //! //! # fn main() { f().unwrap(); } //! # fn f() -> Result<()> { //! let p = &StandardPolicy::new(); //! //! # let (cert, _) = //! # CertBuilder::general_purpose(None, Some("alice@example.org")) //! # .generate()?; //! let decryption_keys = cert.keys().with_policy(p, None) //! .for_storage_encryption().for_transport_encryption() //! .collect::<Vec<_>>(); //! # Ok(()) //! # } //! ``` //! //! [`KeyAmalgamation`]: struct.KeyAmalgamation.html //! [`ComponentAmalgamation`]: ../struct.ComponentAmalgamation.html //! [`Key`]: ../../../packet/key/index.html //! [`Cert::keys`]: ../../struct.Cert.html#method.keys //! [`PrimaryKeyAmalgamation`]: ../type.PrimaryKeyAmalgamation.html //! [`SubordinateKeyAmalgamation`]: ../type.SubordinateKeyAmalgamation.html //! [`ErasedKeyAmalgamation`]: ../type.ErasedKeyAmalgamation.html //! [`KeyRole::UnspecifiedRole`]: ../../../packet/key/trait.KeyRole.html //! [`Policy` discussion]: ../index.html //! [This discussion]: https://crypto.stackexchange.com/a/12138 use std::time; use std::time::SystemTime; use std::ops::Deref; use std::borrow::Borrow; use std::convert::TryFrom; use std::convert::TryInto; use anyhow::Context; use crate::{ Cert, cert::bundle::KeyBundle, cert::amalgamation::{ ComponentAmalgamation, ValidAmalgamation, ValidateAmalgamation, }, cert::ValidCert, crypto::Signer, Error, packet::Key, packet::key, packet::Signature, packet::signature, packet::signature::subpacket::SubpacketTag, policy::Policy, Result, types::{ KeyFlags, RevocationStatus, SignatureType, }, }; mod iter; pub use iter::{ KeyAmalgamationIter, ValidKeyAmalgamationIter, }; /// Whether the key is a primary key. /// /// This trait is an implementation detail. It exists so that we can /// have a blanket implementation of [`ValidAmalgamation`] for /// [`ValidKeyAmalgamation`], for instance, even though we only have /// specialized implementations of `PrimaryKey`. /// /// [`ValidAmalgamation`]: ../trait.ValidAmalgamation.html /// [`ValidKeyAmalgamation`]: struct.ValidKeyAmalgamation.html pub trait PrimaryKey<'a, P, R> where P: 'a + key::KeyParts, R: 'a + key::KeyRole, { /// Returns whether the key amalgamation is a primary key /// amalgamation. /// /// # Examples /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// # use openpgp::policy::StandardPolicy; /// # /// # fn main() -> openpgp::Result<()> { /// # let p = &StandardPolicy::new(); /// # let (cert, _) = /// # CertBuilder::general_purpose(None, Some("alice@example.org")) /// # .generate()?; /// # let fpr = cert.fingerprint(); /// // This works if the type is concrete: /// let ka: PrimaryKeyAmalgamation<_> = cert.primary_key(); /// assert!(ka.primary()); /// /// // Or if it has been erased: /// for (i, ka) in cert.keys().enumerate() { /// let ka: ErasedKeyAmalgamation<_> = ka; /// if i == 0 { /// // The primary key is always the first key returned by /// // `Cert::keys`. /// assert!(ka.primary()); /// } else { /// // The rest are subkeys. /// assert!(! ka.primary()); /// } /// } /// # Ok(()) } /// ``` fn primary(&self) -> bool; } /// A key, and its associated data, and useful methods. /// /// A `KeyAmalgamation` is like a [`ComponentAmalgamation`], but /// specialized for keys. Due to the requirement to keep track of the /// key's role when it is erased ([see the module's documentation] for /// more details), this is a different data structure rather than a /// specialized type alias. /// /// Generally, you won't use this type directly, but instead use /// [`PrimaryKeyAmalgamation`], [`SubordinateKeyAmalgamation`], or /// [`ErasedKeyAmalgamation`]. /// /// A `KeyAmalgamation` is returned by [`Cert::primary_key`], and /// [`Cert::keys`]. /// /// `KeyAmalgamation` implements [`ValidateAmalgamation`], which /// allows you to turn a `KeyAmalgamation` into a /// [`ValidKeyAmalgamation`] using [`KeyAmalgamation::with_policy`]. /// /// # Examples /// /// Iterating over all keys: /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// # use openpgp::policy::StandardPolicy; /// # /// # fn main() -> openpgp::Result<()> { /// # let p = &StandardPolicy::new(); /// # let (cert, _) = /// # CertBuilder::general_purpose(None, Some("alice@example.org")) /// # .generate()?; /// # let fpr = cert.fingerprint(); /// for ka in cert.keys() { /// let ka: ErasedKeyAmalgamation<_> = ka; /// } /// # Ok(()) /// # } /// ``` /// /// Getting the primary key: /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// # use openpgp::policy::StandardPolicy; /// # /// # fn main() -> openpgp::Result<()> { /// # let p = &StandardPolicy::new(); /// # let (cert, _) = /// # CertBuilder::general_purpose(None, Some("alice@example.org")) /// # .generate()?; /// # let fpr = cert.fingerprint(); /// let ka: PrimaryKeyAmalgamation<_> = cert.primary_key(); /// # Ok(()) /// # } /// ``` /// /// Iterating over just the subkeys: /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// # use openpgp::policy::StandardPolicy; /// # /// # fn main() -> openpgp::Result<()> { /// # let p = &StandardPolicy::new(); /// # let (cert, _) = /// # CertBuilder::general_purpose(None, Some("alice@example.org")) /// # .generate()?; /// # let fpr = cert.fingerprint(); /// // We can skip the primary key (it's always first): /// for ka in cert.keys().skip(1) { /// let ka: ErasedKeyAmalgamation<_> = ka; /// } /// /// // Or use `subkeys`, which returns a more accurate type: /// for ka in cert.keys().subkeys() { /// let ka: SubordinateKeyAmalgamation<_> = ka; /// } /// # Ok(()) /// # } /// ``` /// /// [`ComponentAmalgamation`]: ../struct.ComponentAmalgamation.html /// [see the module's documentation]: index.html /// [`PrimaryKeyAmalgamation`]: type.PrimaryKeyAmalgamation.html /// [`SubordinateKeyAmalgamation`]: type.SubordinateKeyAmalgamation.html /// [`ErasedKeyAmalgamation`]: type.ErasedKeyAmalgamation.html /// [`Cert::primary_key`]: ../../../cert/struct.Cert.html#method.primary_key /// [`Cert::keys`]: ../../../cert/struct.Cert.html#method.keys /// [`ValidateAmalgamation`]: ../trait.ValidateAmalgamation.html /// [`ValidKeyAmalgamation`]: struct.ValidKeyAmalgamation.html /// [`KeyAmalgamation::with_policy`]: ../trait.ValidateAmalgamation.html#method.with_policy #[derive(Debug)] pub struct KeyAmalgamation<'a, P, R, R2> where P: 'a + key::KeyParts, R: 'a + key::KeyRole, { ca: ComponentAmalgamation<'a, Key<P, R>>, primary: R2, } // derive(Clone) doesn't work with generic parameters that don't // implement clone. But, we don't need to require that C implements // Clone, because we're not cloning C, just the reference. // // See: https://github.com/rust-lang/rust/issues/26925 impl<'a, P, R, R2> Clone for KeyAmalgamation<'a, P, R, R2> where P: 'a + key::KeyParts, R: 'a + key::KeyRole, R2: Copy, { fn clone(&self) -> Self { Self { ca: self.ca.clone(), primary: self.primary, } } } /// A primary key amalgamation. /// /// A specialized version of [`KeyAmalgamation`]. /// /// [`KeyAmalgamation`]: struct.KeyAmalgamation.html pub type PrimaryKeyAmalgamation<'a, P> = KeyAmalgamation<'a, P, key::PrimaryRole, ()>; /// A subordinate key amalgamation. /// /// A specialized version of [`KeyAmalgamation`]. /// /// [`KeyAmalgamation`]: struct.KeyAmalgamation.html pub type SubordinateKeyAmalgamation<'a, P> = KeyAmalgamation<'a, P, key::SubordinateRole, ()>; /// An amalgamation whose role is not known at compile time. /// /// A specialized version of [`KeyAmalgamation`]. /// /// Unlike a [`Key`] or a [`KeyBundle`] with an unspecified role, an /// `ErasedKeyAmalgamation` remembers its role; it is just not exposed /// to the type system. For details, see the [module-level /// documentation]. /// /// [`KeyAmalgamation`]: struct.KeyAmalgamation.html /// [`Key`]: ../../../packet/key/index.html /// [`KeyBundle`]: ../../bundle/index.html /// [module-level documentation]: index.html pub type ErasedKeyAmalgamation<'a, P> = KeyAmalgamation<'a, P, key::UnspecifiedRole, bool>; impl<'a, P, R, R2> Deref for KeyAmalgamation<'a, P, R, R2> where P: 'a + key::KeyParts, R: 'a + key::KeyRole, { type Target = ComponentAmalgamation<'a, Key<P, R>>; fn deref(&self) -> &Self::Target { &self.ca } } impl<'a, P> ValidateAmalgamation<'a, Key<P, key::PrimaryRole>> for PrimaryKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { type V = ValidPrimaryKeyAmalgamation<'a, P>; fn with_policy<T>(self, policy: &'a dyn Policy, time: T) -> Result<Self::V> where T: Into<Option<time::SystemTime>> { let ka : ErasedKeyAmalgamation<P> = self.into(); Ok(ka.with_policy(policy, time)? .try_into().expect("conversion is symmetric")) } } impl<'a, P> ValidateAmalgamation<'a, Key<P, key::SubordinateRole>> for SubordinateKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { type V = ValidSubordinateKeyAmalgamation<'a, P>; fn with_policy<T>(self, policy: &'a dyn Policy, time: T) -> Result<Self::V> where T: Into<Option<time::SystemTime>> { let ka : ErasedKeyAmalgamation<P> = self.into(); Ok(ka.with_policy(policy, time)? .try_into().expect("conversion is symmetric")) } } impl<'a, P> ValidateAmalgamation<'a, Key<P, key::UnspecifiedRole>> for ErasedKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { type V = ValidErasedKeyAmalgamation<'a, P>; fn with_policy<T>(self, policy: &'a dyn Policy, time: T) -> Result<Self::V> where T: Into<Option<time::SystemTime>> { let time = time.into().unwrap_or_else(SystemTime::now); // We need to make sure the certificate is okay. This means // checking the primary key. But, be careful: we don't need // to double check. if ! self.primary() { let pka = PrimaryKeyAmalgamation::new(self.cert()); pka.with_policy(policy, time).context("primary key")?; } let binding_signature = self.binding_signature(policy, time)?; let cert = self.ca.cert(); let vka = ValidErasedKeyAmalgamation { ka: KeyAmalgamation { ca: self.ca.parts_into_public(), primary: self.primary, }, // We need some black magic to avoid infinite // recursion: a ValidCert must be valid for the // specified policy and reference time. A ValidCert // is consider valid if the primary key is valid. // ValidCert::with_policy checks that by calling this // function. So, if we call ValidCert::with_policy // here we'll recurse infinitely. // // But, hope is not lost! We know that if we get // here, we've already checked that the primary key is // valid (see above), or that we're in the process of // evaluating the primary key's validity and we just // need to check the user's policy. So, it is safe to // create a ValidCert from scratch. cert: ValidCert { cert: cert, policy: policy, time: time, }, binding_signature }; policy.key(&vka)?; Ok(ValidErasedKeyAmalgamation { ka: KeyAmalgamation { ca: P::convert_key_amalgamation( vka.ka.ca.parts_into_unspecified()).expect("roundtrip"), primary: vka.ka.primary, }, cert: vka.cert, binding_signature, }) } } impl<'a, P> PrimaryKey<'a, P, key::PrimaryRole> for PrimaryKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { fn primary(&self) -> bool { true } } impl<'a, P> PrimaryKey<'a, P, key::SubordinateRole> for SubordinateKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { fn primary(&self) -> bool { false } } impl<'a, P> PrimaryKey<'a, P, key::UnspecifiedRole> for ErasedKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { fn primary(&self) -> bool { self.primary } } impl<'a, P: 'a + key::KeyParts> From<PrimaryKeyAmalgamation<'a, P>> for ErasedKeyAmalgamation<'a, P> { fn from(ka: PrimaryKeyAmalgamation<'a, P>) -> Self { ErasedKeyAmalgamation { ca: ka.ca.role_into_unspecified(), primary: true, } } } impl<'a, P: 'a + key::KeyParts> From<SubordinateKeyAmalgamation<'a, P>> for ErasedKeyAmalgamation<'a, P> { fn from(ka: SubordinateKeyAmalgamation<'a, P>) -> Self { ErasedKeyAmalgamation { ca: ka.ca.role_into_unspecified(), primary: false, } } } // We can infallibly convert part X to part Y for everything but // Public -> Secret and Unspecified -> Secret. macro_rules! impl_conversion { ($s:ident, $primary:expr, $p1:path, $p2:path) => { impl<'a> From<$s<'a, $p1>> for ErasedKeyAmalgamation<'a, $p2> { fn from(ka: $s<'a, $p1>) -> Self { ErasedKeyAmalgamation { ca: ka.ca.into(), primary: $primary, } } } } } impl_conversion!(PrimaryKeyAmalgamation, true, key::SecretParts, key::PublicParts); impl_conversion!(PrimaryKeyAmalgamation, true, key::SecretParts, key::UnspecifiedParts); impl_conversion!(PrimaryKeyAmalgamation, true, key::PublicParts, key::UnspecifiedParts); impl_conversion!(PrimaryKeyAmalgamation, true, key::UnspecifiedParts, key::PublicParts); impl_conversion!(SubordinateKeyAmalgamation, false, key::SecretParts, key::PublicParts); impl_conversion!(SubordinateKeyAmalgamation, false, key::SecretParts, key::UnspecifiedParts); impl_conversion!(SubordinateKeyAmalgamation, false, key::PublicParts, key::UnspecifiedParts); impl_conversion!(SubordinateKeyAmalgamation, false, key::UnspecifiedParts, key::PublicParts); impl<'a, P, P2> TryFrom<ErasedKeyAmalgamation<'a, P>> for PrimaryKeyAmalgamation<'a, P2> where P: 'a + key::KeyParts, P2: 'a + key::KeyParts, { type Error = anyhow::Error; fn try_from(ka: ErasedKeyAmalgamation<'a, P>) -> Result<Self> { if ka.primary { Ok(Self { ca: P2::convert_key_amalgamation( ka.ca.role_into_primary().parts_into_unspecified())?, primary: (), }) } else { Err(Error::InvalidArgument( "can't convert a SubordinateKeyAmalgamation \ to a PrimaryKeyAmalgamation".into()).into()) } } } impl<'a, P, P2> TryFrom<ErasedKeyAmalgamation<'a, P>> for SubordinateKeyAmalgamation<'a, P2> where P: 'a + key::KeyParts, P2: 'a + key::KeyParts, { type Error = anyhow::Error; fn try_from(ka: ErasedKeyAmalgamation<'a, P>) -> Result<Self> { if ka.primary { Err(Error::InvalidArgument( "can't convert a PrimaryKeyAmalgamation \ to a SubordinateKeyAmalgamation".into()).into()) } else { Ok(Self { ca: P2::convert_key_amalgamation( ka.ca.role_into_subordinate().parts_into_unspecified())?, primary: (), }) } } } impl<'a> PrimaryKeyAmalgamation<'a, key::PublicParts> { pub(crate) fn new(cert: &'a Cert) -> Self { PrimaryKeyAmalgamation { ca: ComponentAmalgamation::new(cert, &cert.primary), primary: (), } } } impl<'a, P: 'a + key::KeyParts> SubordinateKeyAmalgamation<'a, P> { pub(crate) fn new( cert: &'a Cert, bundle: &'a KeyBundle<P, key::SubordinateRole>) -> Self { SubordinateKeyAmalgamation { ca: ComponentAmalgamation::new(cert, bundle), primary: (), } } } impl<'a, P: 'a + key::KeyParts> ErasedKeyAmalgamation<'a, P> { /// Returns the key's binding signature as of the reference time, /// if any. /// /// Note: this function is not exported. Users of this interface /// should instead do: `ka.with_policy(policy, /// time)?.binding_signature()`. fn binding_signature<T>(&self, policy: &'a dyn Policy, time: T) -> Result<&'a Signature> where T: Into<Option<time::SystemTime>> { let time = time.into().unwrap_or_else(SystemTime::now); if self.primary { self.cert().primary_userid_relaxed(policy, time, false) .map(|u| u.binding_signature()) .or_else(|e0| { // Lookup of the primary user id binding failed. // Look for direct key signatures. self.cert().primary_key().bundle() .binding_signature(policy, time) .or_else(|e1| { // Both lookups failed. Keep the more // meaningful error. if let Some(Error::NoBindingSignature(_)) = e1.downcast_ref() { Err(e0) // Return the original error. } else { Err(e1) } }) }) } else { self.bundle().binding_signature(policy, time) } } } impl<'a, P, R, R2> KeyAmalgamation<'a, P, R, R2> where P: 'a + key::KeyParts, R: 'a + key::KeyRole, { /// Returns the `KeyAmalgamation`'s `ComponentAmalgamation`. pub fn component_amalgamation(&self) -> &ComponentAmalgamation<'a, Key<P, R>> { &self.ca } /// Returns the `KeyAmalgamation`'s key. /// /// Normally, a type implementing `KeyAmalgamation` eventually /// derefs to a `Key`, however, this method provides a more /// accurate lifetime. See the documentation for /// `ComponentAmalgamation::component` for an explanation. pub fn key(&self) -> &'a Key<P, R> { self.ca.component() } } /// A `KeyAmalgamation` plus a `Policy` and a reference time. /// /// In the same way that a [`ValidComponentAmalgamation`] extends a /// [`ComponentAmalgamation`], a `ValidKeyAmalgamation` extends a /// [`KeyAmalgamation`]: a `ValidKeyAmalgamation` combines a /// `KeyAmalgamation`, a [`Policy`], and a reference time. This /// allows it to implement the [`ValidAmalgamation`] trait, which /// provides methods like [`ValidAmalgamation::binding_signature`] that require a /// `Policy` and a reference time. Although `KeyAmalgamation` could /// implement these methods by requiring that the caller explicitly /// pass them in, embedding them in the `ValidKeyAmalgamation` helps /// ensure that multipart operations, even those that span multiple /// functions, use the same `Policy` and reference time. /// /// A `ValidKeyAmalgamation` can be obtained by transforming a /// `KeyAmalgamation` using [`ValidateAmalgamation::with_policy`]. A /// [`KeyAmalgamationIter`] can also be changed to yield /// `ValidKeyAmalgamation`s. /// /// A `ValidKeyAmalgamation` is guaranteed to come from a valid /// certificate, and have a valid and live *binding* signature at the /// specified reference time. Note: this only means that the binding /// signatures are live; it says nothing about whether the /// *certificate* or the *`Key`* is live and non-revoked. If you care /// about those things, you need to check them separately. /// /// # Examples: /// /// Find all non-revoked, live, signing-capable keys: /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// use openpgp::types::RevocationStatus; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// # let (cert, _) = CertBuilder::new() /// # .add_userid("Alice") /// # .add_signing_subkey() /// # .add_transport_encryption_subkey() /// # .generate().unwrap(); /// // `with_policy` ensures that the certificate and any components /// // that it returns have valid *binding signatures*. But, we still /// // need to check that the certificate and `Key` are not revoked, /// // and live. /// // /// // Note: `ValidKeyAmalgamation::revocation_status`, etc. use the /// // embedded policy and timestamp. Even though we used `None` for /// // the timestamp (i.e., now), they are guaranteed to use the same /// // timestamp, because `with_policy` eagerly transforms it into /// // the current time. /// let cert = cert.with_policy(p, None)?; /// if let RevocationStatus::Revoked(_revs) = cert.revocation_status() { /// // Revoked by the certificate holder. (If we care about /// // designated revokers, then we need to check those /// // ourselves.) /// # unreachable!(); /// } else if let Err(_err) = cert.alive() { /// // Certificate was created in the future or is expired. /// # unreachable!(); /// } else { /// // `ValidCert::keys` returns `ValidKeyAmalgamation`s. /// for ka in cert.keys() { /// if let RevocationStatus::Revoked(_revs) = ka.revocation_status() { /// // Revoked by the key owner. (If we care about /// // designated revokers, then we need to check those /// // ourselves.) /// # unreachable!(); /// } else if let Err(_err) = ka.alive() { /// // Key was created in the future or is expired. /// # unreachable!(); /// } else if ! ka.for_signing() { /// // We're looking for a signing-capable key, skip this one. /// } else { /// // Use it! /// } /// } /// } /// # Ok(()) } /// ``` /// /// [`ValidComponentAmalgamation`]: ../struct.ValidComponentAmalgamation.html /// [`ComponentAmalgamation`]: ../struct.ComponentAmalgamation.html /// [`KeyAmalgamation`]: struct.KeyAmalgamation.html /// [`Policy`]: ../../../policy/index.html /// [`ValidAmalgamation`]: ../trait.ValidAmalgamation.html /// [`ValidAmalgamation::binding_signature`]: ../trait.ValidAmalgamation.html#method.binding_signature /// [`ValidateAmalgamation::with_policy`]: ../trait.ValidateAmalgamation.html#tymethod.with_policy /// [`KeyAmalgamationIter`]: struct.KeyAmalgamationIter.html #[derive(Debug, Clone)] pub struct ValidKeyAmalgamation<'a, P, R, R2> where P: 'a + key::KeyParts, R: 'a + key::KeyRole, R2: Copy, { // Ouch, ouch, ouch! ka is a `KeyAmalgamation`, which contains a // reference to a `Cert`. `cert` is a `ValidCert` and contains a // reference to the same `Cert`! We do this so that // `ValidKeyAmalgamation` can deref to a `KeyAmalgamation` and // `ValidKeyAmalgamation::cert` can return a `&ValidCert`. ka: KeyAmalgamation<'a, P, R, R2>, cert: ValidCert<'a>, // The binding signature at time `time`. (This is just a cache.) binding_signature: &'a Signature, } /// A Valid primary Key, and its associated data. /// /// A specialized version of [`ValidKeyAmalgamation`]. /// /// [`ValidKeyAmalgamation`]: struct.ValidKeyAmalgamation.html pub type ValidPrimaryKeyAmalgamation<'a, P> = ValidKeyAmalgamation<'a, P, key::PrimaryRole, ()>; /// A Valid subkey, and its associated data. /// /// A specialized version of [`ValidKeyAmalgamation`]. /// /// [`ValidKeyAmalgamation`]: struct.ValidKeyAmalgamation.html pub type ValidSubordinateKeyAmalgamation<'a, P> = ValidKeyAmalgamation<'a, P, key::SubordinateRole, ()>; /// A valid key whose role is not known at compile time. /// /// A specialized version of [`ValidKeyAmalgamation`]. /// /// [`ValidKeyAmalgamation`]: struct.ValidKeyAmalgamation.html pub type ValidErasedKeyAmalgamation<'a, P> = ValidKeyAmalgamation<'a, P, key::UnspecifiedRole, bool>; impl<'a, P, R, R2> Deref for ValidKeyAmalgamation<'a, P, R, R2> where P: 'a + key::KeyParts, R: 'a + key::KeyRole, R2: Copy, { type Target = KeyAmalgamation<'a, P, R, R2>; fn deref(&self) -> &Self::Target { &self.ka } } impl<'a, P, R, R2> From<ValidKeyAmalgamation<'a, P, R, R2>> for KeyAmalgamation<'a, P, R, R2> where P: 'a + key::KeyParts, R: 'a + key::KeyRole, R2: Copy, { fn from(vka: ValidKeyAmalgamation<'a, P, R, R2>) -> Self { assert!(std::ptr::eq(vka.ka.cert(), vka.cert.cert())); vka.ka } } impl<'a, P: 'a + key::KeyParts> From<ValidPrimaryKeyAmalgamation<'a, P>> for ValidErasedKeyAmalgamation<'a, P> { fn from(vka: ValidPrimaryKeyAmalgamation<'a, P>) -> Self { assert!(std::ptr::eq(vka.ka.cert(), vka.cert.cert())); ValidErasedKeyAmalgamation { ka: vka.ka.into(), cert: vka.cert, binding_signature: vka.binding_signature, } } } impl<'a, P: 'a + key::KeyParts> From<&ValidPrimaryKeyAmalgamation<'a, P>> for ValidErasedKeyAmalgamation<'a, P> { fn from(vka: &ValidPrimaryKeyAmalgamation<'a, P>) -> Self { assert!(std::ptr::eq(vka.ka.cert(), vka.cert.cert())); ValidErasedKeyAmalgamation { ka: vka.ka.clone().into(), cert: vka.cert.clone(), binding_signature: vka.binding_signature, } } } impl<'a, P: 'a + key::KeyParts> From<ValidSubordinateKeyAmalgamation<'a, P>> for ValidErasedKeyAmalgamation<'a, P> { fn from(vka: ValidSubordinateKeyAmalgamation<'a, P>) -> Self { assert!(std::ptr::eq(vka.ka.cert(), vka.cert.cert())); ValidErasedKeyAmalgamation { ka: vka.ka.into(), cert: vka.cert, binding_signature: vka.binding_signature, } } } impl<'a, P: 'a + key::KeyParts> From<&ValidSubordinateKeyAmalgamation<'a, P>> for ValidErasedKeyAmalgamation<'a, P> { fn from(vka: &ValidSubordinateKeyAmalgamation<'a, P>) -> Self { assert!(std::ptr::eq(vka.ka.cert(), vka.cert.cert())); ValidErasedKeyAmalgamation { ka: vka.ka.clone().into(), cert: vka.cert.clone(), binding_signature: vka.binding_signature, } } } // We can infallibly convert part X to part Y for everything but // Public -> Secret and Unspecified -> Secret. macro_rules! impl_conversion { ($s:ident, $p1:path, $p2:path) => { impl<'a> From<$s<'a, $p1>> for ValidErasedKeyAmalgamation<'a, $p2> { fn from(vka: $s<'a, $p1>) -> Self { assert!(std::ptr::eq(vka.ka.cert(), vka.cert.cert())); ValidErasedKeyAmalgamation { ka: vka.ka.into(), cert: vka.cert, binding_signature: vka.binding_signature, } } } impl<'a> From<&$s<'a, $p1>> for ValidErasedKeyAmalgamation<'a, $p2> { fn from(vka: &$s<'a, $p1>) -> Self { assert!(std::ptr::eq(vka.ka.cert(), vka.cert.cert())); ValidErasedKeyAmalgamation { ka: vka.ka.clone().into(), cert: vka.cert.clone(), binding_signature: vka.binding_signature, } } } } } impl_conversion!(ValidPrimaryKeyAmalgamation, key::SecretParts, key::PublicParts); impl_conversion!(ValidPrimaryKeyAmalgamation, key::SecretParts, key::UnspecifiedParts); impl_conversion!(ValidPrimaryKeyAmalgamation, key::PublicParts, key::UnspecifiedParts); impl_conversion!(ValidPrimaryKeyAmalgamation, key::UnspecifiedParts, key::PublicParts); impl_conversion!(ValidSubordinateKeyAmalgamation, key::SecretParts, key::PublicParts); impl_conversion!(ValidSubordinateKeyAmalgamation, key::SecretParts, key::UnspecifiedParts); impl_conversion!(ValidSubordinateKeyAmalgamation, key::PublicParts, key::UnspecifiedParts); impl_conversion!(ValidSubordinateKeyAmalgamation, key::UnspecifiedParts, key::PublicParts); impl<'a, P, P2> TryFrom<ValidErasedKeyAmalgamation<'a, P>> for ValidPrimaryKeyAmalgamation<'a, P2> where P: 'a + key::KeyParts, P2: 'a + key::KeyParts, { type Error = anyhow::Error; fn try_from(vka: ValidErasedKeyAmalgamation<'a, P>) -> Result<Self> { assert!(std::ptr::eq(vka.ka.cert(), vka.cert.cert())); Ok(ValidPrimaryKeyAmalgamation { ka: vka.ka.try_into()?, cert: vka.cert, binding_signature: vka.binding_signature, }) } } impl<'a, P, P2> TryFrom<ValidErasedKeyAmalgamation<'a, P>> for ValidSubordinateKeyAmalgamation<'a, P2> where P: 'a + key::KeyParts, P2: 'a + key::KeyParts, { type Error = anyhow::Error; fn try_from(vka: ValidErasedKeyAmalgamation<'a, P>) -> Result<Self> { Ok(ValidSubordinateKeyAmalgamation { ka: vka.ka.try_into()?, cert: vka.cert, binding_signature: vka.binding_signature, }) } } impl<'a, P> ValidateAmalgamation<'a, Key<P, key::PrimaryRole>> for ValidPrimaryKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { type V = Self; fn with_policy<T>(self, policy: &'a dyn Policy, time: T) -> Result<Self::V> where T: Into<Option<time::SystemTime>>, Self: Sized { assert!(std::ptr::eq(self.ka.cert(), self.cert.cert())); self.ka.with_policy(policy, time) .map(|vka| { assert!(std::ptr::eq(vka.ka.cert(), vka.cert.cert())); vka }) } } impl<'a, P> ValidateAmalgamation<'a, Key<P, key::SubordinateRole>> for ValidSubordinateKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { type V = Self; fn with_policy<T>(self, policy: &'a dyn Policy, time: T) -> Result<Self::V> where T: Into<Option<time::SystemTime>>, Self: Sized { assert!(std::ptr::eq(self.ka.cert(), self.cert.cert())); self.ka.with_policy(policy, time) .map(|vka| { assert!(std::ptr::eq(vka.ka.cert(), vka.cert.cert())); vka }) } } impl<'a, P> ValidateAmalgamation<'a, Key<P, key::UnspecifiedRole>> for ValidErasedKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { type V = Self; fn with_policy<T>(self, policy: &'a dyn Policy, time: T) -> Result<Self::V> where T: Into<Option<time::SystemTime>>, Self: Sized { assert!(std::ptr::eq(self.ka.cert(), self.cert.cert())); self.ka.with_policy(policy, time) .map(|vka| { assert!(std::ptr::eq(vka.ka.cert(), vka.cert.cert())); vka }) } } impl<'a, P, R, R2> ValidAmalgamation<'a, Key<P, R>> for ValidKeyAmalgamation<'a, P, R, R2> where P: 'a + key::KeyParts, R: 'a + key::KeyRole, R2: Copy, Self: PrimaryKey<'a, P, R>, { fn cert(&self) -> &ValidCert<'a> { assert!(std::ptr::eq(self.ka.cert(), self.cert.cert())); &self.cert } fn time(&self) -> SystemTime { self.cert.time() } fn policy(&self) -> &'a dyn Policy { assert!(std::ptr::eq(self.ka.cert(), self.cert.cert())); self.cert.policy() } fn binding_signature(&self) -> &'a Signature { self.binding_signature } fn revocation_status(&self) -> RevocationStatus<'a> { if self.primary() { self.cert.revocation_status() } else { self.bundle()._revocation_status(self.policy(), self.time(), true, Some(self.binding_signature)) } } } impl<'a, P> PrimaryKey<'a, P, key::PrimaryRole> for ValidPrimaryKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { fn primary(&self) -> bool { true } } impl<'a, P> PrimaryKey<'a, P, key::SubordinateRole> for ValidSubordinateKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { fn primary(&self) -> bool { false } } impl<'a, P> PrimaryKey<'a, P, key::UnspecifiedRole> for ValidErasedKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { fn primary(&self) -> bool { self.ka.primary } } impl<'a, P, R, R2> ValidKeyAmalgamation<'a, P, R, R2> where P: 'a + key::KeyParts, R: 'a + key::KeyRole, R2: Copy, Self: ValidAmalgamation<'a, Key<P, R>>, Self: PrimaryKey<'a, P, R>, { /// Returns whether the key is alive as of the amalgamation's /// reference time. /// /// A `ValidKeyAmalgamation` is guaranteed to have a live binding /// signature. This is independent of whether the component is /// live. /// /// If the certificate is not alive as of the reference time, no /// subkey can be alive. /// /// This function considers both the binding signature and the /// direct key signature. Information in the binding signature /// takes precedence over the direct key signature. See [Section /// 5.2.3.3 of RFC 4880]. /// /// [Section 5.2.3.3 of RFC 4880]: https://tools.ietf.org/html/rfc4880#section-5.2.3.3 /// /// For a definition of liveness, see the [`key_alive`] method. /// /// [`key_alive`]: ../../../packet/signature/subpacket/struct.SubpacketAreas.html#method.key_alive /// /// # Examples /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// # let (cert, _) = CertBuilder::new() /// # .add_userid("Alice") /// # .add_signing_subkey() /// # .add_transport_encryption_subkey() /// # .generate().unwrap(); /// let ka = cert.primary_key().with_policy(p, None)?; /// if let Err(_err) = ka.alive() { /// // Not alive. /// # unreachable!(); /// } /// # Ok(()) } /// ``` pub fn alive(&self) -> Result<()> { if ! self.primary() { // First, check the certificate. self.cert().alive()?; } let sig = { let binding : &Signature = self.binding_signature(); if binding.key_validity_period().is_some() { Some(binding) } else { self.direct_key_signature().ok() } }; if let Some(sig) = sig { sig.key_alive(self.key(), self.time()) } else { // There is no key expiration time on the binding // signature. This key does not expire. Ok(()) } } /// Returns the wrapped `KeyAmalgamation`. /// /// # Examples /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// # let (cert, _) = CertBuilder::new() /// # .add_userid("Alice") /// # .add_signing_subkey() /// # .add_transport_encryption_subkey() /// # .generate().unwrap(); /// let ka = cert.primary_key(); /// /// // `with_policy` takes ownership of `ka`. /// let vka = ka.with_policy(p, None)?; /// /// // And here we get it back: /// let ka = vka.into_key_amalgamation(); /// # Ok(()) } /// ``` pub fn into_key_amalgamation(self) -> KeyAmalgamation<'a, P, R, R2> { self.ka } } impl<'a, P> ValidPrimaryKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { /// Sets the key to expire in delta seconds. /// /// Note: the time is relative to the key's creation time, not the /// current time! /// /// This function exists to facilitate testing, which is why it is /// not exported. #[cfg(test)] pub(crate) fn set_validity_period_as_of(&self, primary_signer: &mut dyn Signer, expiration: Option<time::Duration>, now: time::SystemTime) -> Result<Vec<Signature>> { ValidErasedKeyAmalgamation::<P>::from(self) .set_validity_period_as_of(primary_signer, None, expiration, now) } /// Creates signatures that cause the key to expire at the specified time. /// /// This function creates new binding signatures that cause the /// key to expire at the specified time when integrated into the /// certificate. For the primary key, it is necessary to /// create a new self-signature for each non-revoked User ID, and /// to create a direct key signature. This is needed, because the /// primary User ID is first consulted when determining the /// primary key's expiration time, and certificates can be /// distributed with a possibly empty subset of User IDs. /// /// Setting a key's expiry time means updating an existing binding /// signature---when looking up information, only one binding /// signature is normally considered, and we don't want to drop /// the other information stored in the current binding signature. /// This function uses the binding signature determined by /// `ValidKeyAmalgamation`'s policy and reference time for this. /// /// # Examples /// /// ``` /// use std::time; /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// # let t = time::SystemTime::now() - time::Duration::from_secs(10); /// # let (cert, _) = CertBuilder::new() /// # .set_creation_time(t) /// # .add_userid("Alice") /// # .add_signing_subkey() /// # .add_transport_encryption_subkey() /// # .generate().unwrap(); /// let vc = cert.with_policy(p, None)?; /// /// // Assert that the primary key is not expired. /// assert!(vc.primary_key().alive().is_ok()); /// /// // Make the primary key expire in a week. /// let t = time::SystemTime::now() /// + time::Duration::from_secs(7 * 24 * 60 * 60); /// /// // We assume that the secret key material is available, and not /// // password protected. /// let mut signer = vc.primary_key() /// .key().clone().parts_into_secret()?.into_keypair()?; /// /// let sigs = vc.primary_key().set_expiration_time(&mut signer, Some(t))?; /// let cert = cert.insert_packets(sigs)?; /// /// // The primary key isn't expired yet. /// let vc = cert.with_policy(p, None)?; /// assert!(vc.primary_key().alive().is_ok()); /// /// // But in two weeks, it will be... /// let t = time::SystemTime::now() /// + time::Duration::from_secs(2 * 7 * 24 * 60 * 60); /// let vc = cert.with_policy(p, t)?; /// assert!(vc.primary_key().alive().is_err()); /// # Ok(()) } pub fn set_expiration_time(&self, primary_signer: &mut dyn Signer, expiration: Option<time::SystemTime>) -> Result<Vec<Signature>> { ValidErasedKeyAmalgamation::<P>::from(self) .set_expiration_time(primary_signer, None, expiration) } } impl<'a, P> ValidSubordinateKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { /// Creates signatures that cause the key to expire at the specified time. /// /// This function creates new binding signatures that cause the /// key to expire at the specified time when integrated into the /// certificate. For subkeys, a single `Signature` is returned. /// /// Setting a key's expiry time means updating an existing binding /// signature---when looking up information, only one binding /// signature is normally considered, and we don't want to drop /// the other information stored in the current binding signature. /// This function uses the binding signature determined by /// `ValidKeyAmalgamation`'s policy and reference time for this. /// /// When updating the expiration time of signing-capable subkeys, /// we need to create a new [primary key binding signature]. /// Therefore, we need a signer for the subkey. If /// `subkey_signer` is `None`, and this is a signing-capable /// subkey, this function fails with [`Error::InvalidArgument`]. /// Likewise, this function fails if `subkey_signer` is not `None` /// when updating the expiration of an non signing-capable subkey. /// /// [primary key binding signature]: https://tools.ietf.org/html/rfc4880#section-5.2.1 /// [`Error::InvalidArgument`]: ../../../enum.Error.html#variant.InvalidArgument /// /// # Examples /// /// ``` /// use std::time; /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// # let t = time::SystemTime::now() - time::Duration::from_secs(10); /// # let (cert, _) = CertBuilder::new() /// # .set_creation_time(t) /// # .add_userid("Alice") /// # .add_signing_subkey() /// # .add_transport_encryption_subkey() /// # .generate().unwrap(); /// let vc = cert.with_policy(p, None)?; /// /// // Assert that the keys are not expired. /// for ka in vc.keys() { /// assert!(ka.alive().is_ok()); /// } /// /// // Make the keys expire in a week. /// let t = time::SystemTime::now() /// + time::Duration::from_secs(7 * 24 * 60 * 60); /// /// // We assume that the secret key material is available, and not /// // password protected. /// let mut primary_signer = vc.primary_key() /// .key().clone().parts_into_secret()?.into_keypair()?; /// let mut signing_subkey_signer = vc.keys().for_signing().nth(0).unwrap() /// .key().clone().parts_into_secret()?.into_keypair()?; /// /// let mut sigs = Vec::new(); /// for ka in vc.keys() { /// if ! ka.for_signing() { /// // Non-signing-capable subkeys are easy to update. /// sigs.append(&mut ka.set_expiration_time(&mut primary_signer, /// None, Some(t))?); /// } else { /// // Signing-capable subkeys need to create a primary /// // key binding signature with the subkey: /// assert!(ka.set_expiration_time(&mut primary_signer, /// None, Some(t)).is_err()); /// /// // Here, we need the subkey's signer: /// sigs.append(&mut ka.set_expiration_time(&mut primary_signer, /// Some(&mut signing_subkey_signer), /// Some(t))?); /// } /// } /// let cert = cert.insert_packets(sigs)?; /// /// // They aren't expired yet. /// let vc = cert.with_policy(p, None)?; /// for ka in vc.keys() { /// assert!(ka.alive().is_ok()); /// } /// /// // But in two weeks, they will be... /// let t = time::SystemTime::now() /// + time::Duration::from_secs(2 * 7 * 24 * 60 * 60); /// let vc = cert.with_policy(p, t)?; /// for ka in vc.keys() { /// assert!(ka.alive().is_err()); /// } /// # Ok(()) } pub fn set_expiration_time(&self, primary_signer: &mut dyn Signer, subkey_signer: Option<&mut dyn Signer>, expiration: Option<time::SystemTime>) -> Result<Vec<Signature>> { ValidErasedKeyAmalgamation::<P>::from(self) .set_expiration_time(primary_signer, subkey_signer, expiration) } } impl<'a, P> ValidErasedKeyAmalgamation<'a, P> where P: 'a + key::KeyParts { /// Sets the key to expire in delta seconds. /// /// Note: the time is relative to the key's creation time, not the /// current time! /// /// This function exists to facilitate testing, which is why it is /// not exported. pub(crate) fn set_validity_period_as_of(&self, primary_signer: &mut dyn Signer, subkey_signer: Option<&mut dyn Signer>, expiration: Option<time::Duration>, now: time::SystemTime) -> Result<Vec<Signature>> { let mut sigs = Vec::new(); // There are two cases to consider. If we are extending the // validity of the primary key, we also need to create new // binding signatures for all userids. if self.primary() { // First, update or create a direct key signature. let template = self.direct_key_signature() .map(|sig| { signature::SignatureBuilder::from(sig.clone()) }) .unwrap_or_else(|_| { let mut template = signature::SignatureBuilder::from( self.binding_signature().clone()) .set_type(SignatureType::DirectKey); // We're creating a direct signature from a User // ID self signature. Remove irrelevant packets. use SubpacketTag::*; let ha = template.hashed_area_mut(); ha.remove_all(ExportableCertification); ha.remove_all(Revocable); ha.remove_all(TrustSignature); ha.remove_all(RegularExpression); ha.remove_all(PrimaryUserID); ha.remove_all(SignersUserID); ha.remove_all(ReasonForRevocation); ha.remove_all(SignatureTarget); ha.remove_all(EmbeddedSignature); template }); let mut builder = template .set_signature_creation_time(now)? .set_key_validity_period(expiration)?; builder.hashed_area_mut().remove_all( signature::subpacket::SubpacketTag::PrimaryUserID); // Generate the signature. sigs.push(builder.sign_direct_key(primary_signer, &self.cert().primary_key())?); // Second, generate a new binding signature for every // userid. We need to be careful not to change the // primary userid, so we make it explicit using the // primary userid subpacket. for userid in self.cert().userids().revoked(false) { // To extend the validity of the subkey, create a new // binding signature with updated key validity period. let binding_signature = userid.binding_signature(); let builder = signature::SignatureBuilder::from(binding_signature.clone()) .set_signature_creation_time(now)? .set_key_validity_period(expiration)? .set_primary_userid( self.cert().primary_userid().map(|primary| { userid.userid() == primary.userid() }).unwrap_or(false))?; sigs.push(builder.sign_userid_binding(primary_signer, &self.cert().primary_key(), &userid)?); } } else { // To extend the validity of the subkey, create a new // binding signature with updated key validity period. let backsig = if self.for_certification() || self.for_signing() { if let Some(subkey_signer) = subkey_signer { Some(signature::SignatureBuilder::new( SignatureType::PrimaryKeyBinding) .set_signature_creation_time(now)? .set_hash_algo(self.binding_signature.hash_algo()) .sign_primary_key_binding( subkey_signer, &self.cert().primary_key(), self.key().role_as_subordinate())?) } else { return Err(Error::InvalidArgument( "Changing expiration of signing-capable subkeys \ requires subkey signer".into()).into()); } } else { if subkey_signer.is_some() { return Err(Error::InvalidArgument( "Subkey signer given but subkey is not signing-capable" .into()).into()); } None }; let mut sig = signature::SignatureBuilder::from( self.binding_signature().clone()) .set_signature_creation_time(now)? .set_key_validity_period(expiration)?; if let Some(bs) = backsig { sig = sig.set_embedded_signature(bs)?; } sigs.push(sig.sign_subkey_binding( primary_signer, &self.cert().primary_key(), self.key().role_as_subordinate())?); } Ok(sigs) } /// Creates signatures that cause the key to expire at the specified time. /// /// This function creates new binding signatures that cause the /// key to expire at the specified time when integrated into the /// certificate. For subkeys, only a single `Signature` is /// returned. For the primary key, however, it is necessary to /// create a new self-signature for each non-revoked User ID, and /// to create a direct key signature. This is needed, because the /// primary User ID is first consulted when determining the /// primary key's expiration time, and certificates can be /// distributed with a possibly empty subset of User IDs. /// /// Setting a key's expiry time means updating an existing binding /// signature---when looking up information, only one binding /// signature is normally considered, and we don't want to drop /// the other information stored in the current binding signature. /// This function uses the binding signature determined by /// `ValidKeyAmalgamation`'s policy and reference time for this. /// /// When updating the expiration time of signing-capable subkeys, /// we need to create a new [primary key binding signature]. /// Therefore, we need a signer for the subkey. If /// `subkey_signer` is `None`, and this is a signing-capable /// subkey, this function fails with [`Error::InvalidArgument`]. /// Likewise, this function fails if `subkey_signer` is not `None` /// when updating the expiration of the primary key, or an non /// signing-capable subkey. /// /// [primary key binding signature]: https://tools.ietf.org/html/rfc4880#section-5.2.1 /// [`Error::InvalidArgument`]: ../../../enum.Error.html#variant.InvalidArgument /// /// # Examples /// /// ``` /// use std::time; /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// # let t = time::SystemTime::now() - time::Duration::from_secs(10); /// # let (cert, _) = CertBuilder::new() /// # .set_creation_time(t) /// # .add_userid("Alice") /// # .add_signing_subkey() /// # .add_transport_encryption_subkey() /// # .generate().unwrap(); /// let vc = cert.with_policy(p, None)?; /// /// // Assert that the keys are not expired. /// for ka in vc.keys() { /// assert!(ka.alive().is_ok()); /// } /// /// // Make the keys expire in a week. /// let t = time::SystemTime::now() /// + time::Duration::from_secs(7 * 24 * 60 * 60); /// /// // We assume that the secret key material is available, and not /// // password protected. /// let mut primary_signer = vc.primary_key() /// .key().clone().parts_into_secret()?.into_keypair()?; /// let mut signing_subkey_signer = vc.keys().for_signing().nth(0).unwrap() /// .key().clone().parts_into_secret()?.into_keypair()?; /// /// let mut sigs = Vec::new(); /// for ka in vc.keys() { /// if ! ka.for_signing() { /// // Non-signing-capable subkeys are easy to update. /// sigs.append(&mut ka.set_expiration_time(&mut primary_signer, /// None, Some(t))?); /// } else { /// // Signing-capable subkeys need to create a primary /// // key binding signature with the subkey: /// assert!(ka.set_expiration_time(&mut primary_signer, /// None, Some(t)).is_err()); /// /// // Here, we need the subkey's signer: /// sigs.append(&mut ka.set_expiration_time(&mut primary_signer, /// Some(&mut signing_subkey_signer), /// Some(t))?); /// } /// } /// let cert = cert.insert_packets(sigs)?; /// /// // They aren't expired yet. /// let vc = cert.with_policy(p, None)?; /// for ka in vc.keys() { /// assert!(ka.alive().is_ok()); /// } /// /// // But in two weeks, they will be... /// let t = time::SystemTime::now() /// + time::Duration::from_secs(2 * 7 * 24 * 60 * 60); /// let vc = cert.with_policy(p, t)?; /// for ka in vc.keys() { /// assert!(ka.alive().is_err()); /// } /// # Ok(()) } pub fn set_expiration_time(&self, primary_signer: &mut dyn Signer, subkey_signer: Option<&mut dyn Signer>, expiration: Option<time::SystemTime>) -> Result<Vec<Signature>> { let expiration = if let Some(e) = expiration.map(crate::types::normalize_systemtime) { let ct = self.creation_time(); match e.duration_since(ct) { Ok(v) => Some(v), Err(_) => return Err(Error::InvalidArgument( format!("Expiration time {:?} predates creation time \ {:?}", e, ct)).into()), } } else { None }; self.set_validity_period_as_of(primary_signer, subkey_signer, expiration, time::SystemTime::now()) } } impl<'a, P, R, R2> ValidKeyAmalgamation<'a, P, R, R2> where P: 'a + key::KeyParts, R: 'a + key::KeyRole, R2: Copy, Self: ValidAmalgamation<'a, Key<P, R>> { /// Returns the key's `Key Flags`. /// /// A Key's [`Key Flags`] holds information about the key. As of /// RFC 4880, this information is primarily concerned with the /// key's capabilities (e.g., whether it may be used for signing). /// The other information that has been defined is: whether the /// key has been split using something like [SSS], and whether the /// primary key material is held by multiple parties. In /// practice, the latter two flags are ignored. /// /// As per [Section 5.2.3.3 of RFC 4880], when looking for the /// `Key Flags`, the key's binding signature is first consulted /// (in the case of the primary Key, this is the binding signature /// of the primary User ID). If the `Key Flags` subpacket is not /// present, then the direct key signature is consulted. /// /// Since the key flags are taken from the active self signature, /// a key's flags may change depending on the policy and the /// reference time. /// /// [`Key Flags`]: https://tools.ietf.org/html/rfc4880#section-5.2.3.21 /// [SSS]: https://de.wikipedia.org/wiki/Shamir%E2%80%99s_Secret_Sharing /// [Section 5.2.3.3 of RFC 4880]: https://tools.ietf.org/html/rfc4880#section-5.2.3.3 /// /// # Examples /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// # use openpgp::policy::{Policy, StandardPolicy}; /// # /// # fn main() -> openpgp::Result<()> { /// # let p: &dyn Policy = &StandardPolicy::new(); /// # let (cert, _) = /// # CertBuilder::general_purpose(None, Some("alice@example.org")) /// # .generate()?; /// # let cert = cert.with_policy(p, None)?; /// let ka = cert.primary_key(); /// println!("Primary Key's Key Flags: {:?}", ka.key_flags()); /// # assert!(ka.key_flags().unwrap().for_certification()); /// # Ok(()) } /// ``` pub fn key_flags(&self) -> Option<KeyFlags> { self.map(|s| s.key_flags()) } /// Returns whether the key has at least one of the specified key /// flags. /// /// The key flags are looked up as described in /// [`ValidKeyAmalgamation::key_flags`]. /// /// # Examples /// /// Finds keys that may be used for transport encryption (data in /// motion) *or* storage encryption (data at rest): /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// use openpgp::types::KeyFlags; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// # let (cert, _) = /// # CertBuilder::general_purpose(None, Some("alice@example.org")) /// # .generate()?; /// for ka in cert.keys().with_policy(p, None) { /// if ka.has_any_key_flag(KeyFlags::empty() /// .set_storage_encryption() /// .set_transport_encryption()) /// { /// // `ka` is encryption capable. /// } /// } /// # Ok(()) } /// ``` /// /// [`ValidKeyAmalgamation::key_flags`]: #method.key_flags pub fn has_any_key_flag<F>(&self, flags: F) -> bool where F: Borrow<KeyFlags> { let our_flags = self.key_flags().unwrap_or_else(KeyFlags::empty); !(&our_flags & flags.borrow()).is_empty() } /// Returns whether the key is certification capable. /// /// Note: [Section 12.1 of RFC 4880] says that the primary key is /// certification capable independent of the `Key Flags` /// subpacket: /// /// > In a V4 key, the primary key MUST be a key capable of /// > certification. /// /// This function only reflects what is stored in the `Key Flags` /// packet; it does not implicitly set this flag. In practice, /// there are keys whose primary key's `Key Flags` do not have the /// certification capable flag set. Some versions of netpgp, for /// instance, create keys like this. Sequoia's higher-level /// functionality correctly handles these keys by always /// considering the primary key to be certification capable. /// Users of this interface should too. /// /// The key flags are looked up as described in /// [`ValidKeyAmalgamation::key_flags`]. /// /// # Examples /// /// Finds keys that are certification capable: /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// # let (cert, _) = /// # CertBuilder::general_purpose(None, Some("alice@example.org")) /// # .generate()?; /// for ka in cert.keys().with_policy(p, None) { /// if ka.primary() || ka.for_certification() { /// // `ka` is certification capable. /// } /// } /// # Ok(()) } /// ``` /// /// [Section 12.1 of RFC 4880]: https://tools.ietf.org/html/rfc4880#section-5.2.3.21 /// [`ValidKeyAmalgamation::key_flags`]: #method.key_flags pub fn for_certification(&self) -> bool { self.has_any_key_flag(KeyFlags::empty().set_certification()) } /// Returns whether the key is signing capable. /// /// The key flags are looked up as described in /// [`ValidKeyAmalgamation::key_flags`]. /// /// # Examples /// /// Finds keys that are signing capable: /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// # let (cert, _) = /// # CertBuilder::general_purpose(None, Some("alice@example.org")) /// # .generate()?; /// for ka in cert.keys().with_policy(p, None) { /// if ka.for_signing() { /// // `ka` is signing capable. /// } /// } /// # Ok(()) } /// ``` /// /// [`ValidKeyAmalgamation::key_flags`]: #method.key_flags pub fn for_signing(&self) -> bool { self.has_any_key_flag(KeyFlags::empty().set_signing()) } /// Returns whether the key is authentication capable. /// /// The key flags are looked up as described in /// [`ValidKeyAmalgamation::key_flags`]. /// /// # Examples /// /// Finds keys that are authentication capable: /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// # let (cert, _) = /// # CertBuilder::general_purpose(None, Some("alice@example.org")) /// # .generate()?; /// for ka in cert.keys().with_policy(p, None) { /// if ka.for_authentication() { /// // `ka` is authentication capable. /// } /// } /// # Ok(()) } /// ``` /// /// [`ValidKeyAmalgamation::key_flags`]: #method.key_flags pub fn for_authentication(&self) -> bool { self.has_any_key_flag(KeyFlags::empty().set_authentication()) } /// Returns whether the key is storage-encryption capable. /// /// OpenPGP distinguishes two types of encryption keys: those for /// storage ([data at rest]) and those for transport ([data in /// transit]). Most OpenPGP implementations, however, don't /// distinguish between them in practice. Instead, when they /// create a new encryption key, they just set both flags. /// Likewise, when encrypting a message, it is not typically /// possible to indicate the type of protection that is needed. /// Sequoia supports creating keys with only one of these flags /// set, and makes it easy to select the right type of key when /// encrypting messages. /// /// The key flags are looked up as described in /// [`ValidKeyAmalgamation::key_flags`]. /// /// # Examples /// /// Finds keys that are storage-encryption capable: /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// # let (cert, _) = /// # CertBuilder::general_purpose(None, Some("alice@example.org")) /// # .generate()?; /// for ka in cert.keys().with_policy(p, None) { /// if ka.for_storage_encryption() { /// // `ka` is storage-encryption capable. /// } /// } /// # Ok(()) } /// ``` /// /// [data at rest]: https://en.wikipedia.org/wiki/Data_at_rest /// [data in transit]: https://en.wikipedia.org/wiki/Data_in_transit /// [`ValidKeyAmalgamation::key_flags`]: #method.key_flags pub fn for_storage_encryption(&self) -> bool { self.has_any_key_flag(KeyFlags::empty().set_storage_encryption()) } /// Returns whether the key is transport-encryption capable. /// /// OpenPGP distinguishes two types of encryption keys: those for /// storage ([data at rest]) and those for transport ([data in /// transit]). Most OpenPGP implementations, however, don't /// distinguish between them in practice. Instead, when they /// create a new encryption key, they just set both flags. /// Likewise, when encrypting a message, it is not typically /// possible to indicate the type of protection that is needed. /// Sequoia supports creating keys with only one of these flags /// set, and makes it easy to select the right type of key when /// encrypting messages. /// /// The key flags are looked up as described in /// [`ValidKeyAmalgamation::key_flags`]. /// /// # Examples /// /// Finds keys that are transport-encryption capable: /// /// ``` /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// # let (cert, _) = /// # CertBuilder::general_purpose(None, Some("alice@example.org")) /// # .generate()?; /// for ka in cert.keys().with_policy(p, None) { /// if ka.for_transport_encryption() { /// // `ka` is transport-encryption capable. /// } /// } /// # Ok(()) } /// ``` /// /// [data at rest]: https://en.wikipedia.org/wiki/Data_at_rest /// [data in transit]: https://en.wikipedia.org/wiki/Data_in_transit /// [`ValidKeyAmalgamation::key_flags`]: #method.key_flags pub fn for_transport_encryption(&self) -> bool { self.has_any_key_flag(KeyFlags::empty().set_transport_encryption()) } /// Returns how long the key is live. /// /// This returns how long the key is live relative to its creation /// time. Use [`ValidKeyAmalgamation::key_expiration_time`] to /// get the key's absolute expiry time. /// /// This function considers both the binding signature and the /// direct key signature. Information in the binding signature /// takes precedence over the direct key signature. See [Section /// 5.2.3.3 of RFC 4880]. /// /// # Examples /// /// ``` /// use std::time; /// use std::convert::TryInto; /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// use openpgp::types::Timestamp; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// // OpenPGP Timestamps have a one-second resolution. Since we /// // want to round trip the time, round it down. /// let now: Timestamp = time::SystemTime::now().try_into()?; /// let now: time::SystemTime = now.try_into()?; /// /// let a_week = time::Duration::from_secs(7 * 24 * 60 * 60); /// /// let (cert, _) = /// CertBuilder::general_purpose(None, Some("alice@example.org")) /// .set_creation_time(now) /// .set_validity_period(a_week) /// .generate()?; /// /// assert_eq!(cert.primary_key().with_policy(p, None)?.key_validity_period(), /// Some(a_week)); /// # Ok(()) } /// ``` /// /// [`ValidKeyAmalgamation::key_expiration_time`]: #method.key_expiration_time /// [Section 5.2.3.3 of RFC 4880]: https://tools.ietf.org/html/rfc4880#section-5.2.3.3 pub fn key_validity_period(&self) -> Option<std::time::Duration> { self.map(|s| s.key_validity_period()) } /// Returns the key's expiration time. /// /// If this function returns `None`, the key does not expire. /// /// This returns the key's expiration time. Use /// [`ValidKeyAmalgamation::key_validity_period`] to get the /// duration of the key's lifetime. /// /// This function considers both the binding signature and the /// direct key signature. Information in the binding signature /// takes precedence over the direct key signature. See [Section /// 5.2.3.3 of RFC 4880]. /// /// # Examples /// /// ``` /// use std::time; /// use std::convert::TryInto; /// # use sequoia_openpgp as openpgp; /// # use openpgp::cert::prelude::*; /// use openpgp::policy::StandardPolicy; /// use openpgp::types::Timestamp; /// /// # fn main() -> openpgp::Result<()> { /// let p = &StandardPolicy::new(); /// /// // OpenPGP Timestamps have a one-second resolution. Since we /// // want to round trip the time, round it down. /// let now: Timestamp = time::SystemTime::now().try_into()?; /// let now: time::SystemTime = now.try_into()?; // /// let a_week = time::Duration::from_secs(7 * 24 * 60 * 60); /// let a_week_later = now + a_week; /// /// let (cert, _) = /// CertBuilder::general_purpose(None, Some("alice@example.org")) /// .set_creation_time(now) /// .set_validity_period(a_week) /// .generate()?; /// /// assert_eq!(cert.primary_key().with_policy(p, None)?.key_expiration_time(), /// Some(a_week_later)); /// # Ok(()) } /// ``` /// /// [`ValidKeyAmalgamation::key_validity_period`]: #method.key_validity_period /// [Section 5.2.3.3 of RFC 4880]: https://tools.ietf.org/html/rfc4880#section-5.2.3.3 pub fn key_expiration_time(&self) -> Option<time::SystemTime> { match self.key_validity_period() { Some(vp) if vp.as_secs() > 0 => Some(self.key().creation_time() + vp), _ => None, } } // NOTE: If you add a method to ValidKeyAmalgamation that takes // ownership of self, then don't forget to write a forwarder for // it for ValidPrimaryKeyAmalgamation. } #[cfg(test)] mod test { use crate::policy::StandardPolicy as P; use crate::cert::prelude::*; use crate::packet::Packet; use super::*; #[test] fn expire_subkeys() { let p = &P::new(); // Timeline: // // -1: Key created with no key expiration. // 0: Setkeys set to expire in 1 year // 1: Subkeys expire let now = time::SystemTime::now(); let a_year = time::Duration::from_secs(365 * 24 * 60 * 60); let in_a_year = now + a_year; let in_two_years = now + 2 * a_year; let (cert, _) = CertBuilder::new() .set_creation_time(now - a_year) .add_signing_subkey() .add_transport_encryption_subkey() .generate().unwrap(); for ka in cert.keys().with_policy(p, None) { assert!(ka.alive().is_ok()); } let mut primary_signer = cert.primary_key().key().clone() .parts_into_secret().unwrap().into_keypair().unwrap(); let mut signing_subkey_signer = cert.with_policy(p, None).unwrap() .keys().for_signing().nth(0).unwrap() .key().clone().parts_into_secret().unwrap() .into_keypair().unwrap(); // Only expire the subkeys. let sigs = cert.keys().subkeys().with_policy(p, None) .flat_map(|ka| { if ! ka.for_signing() { ka.set_expiration_time(&mut primary_signer, None, Some(in_a_year)).unwrap() } else { ka.set_expiration_time(&mut primary_signer, Some(&mut signing_subkey_signer), Some(in_a_year)).unwrap() } .into_iter() .map(Into::into) }) .collect::<Vec<Packet>>(); let cert = cert.insert_packets(sigs).unwrap(); for ka in cert.keys().with_policy(p, None) { assert!(ka.alive().is_ok()); } // Primary should not be expired two years from now. assert!(cert.primary_key().with_policy(p, in_two_years).unwrap() .alive().is_ok()); // But the subkeys should be. for ka in cert.keys().subkeys().with_policy(p, in_two_years) { assert!(ka.alive().is_err()); } } /// Test that subkeys of expired certificates are also considered /// expired. #[test] fn issue_564() -> Result<()> { use crate::parse::Parse; use crate::packet::signature::subpacket::SubpacketTag; let p = &P::new(); let cert = Cert::from_bytes(crate::tests::key("testy.pgp"))?; assert!(cert.with_policy(p, None)?.alive().is_err()); let subkey = cert.with_policy(p, None)?.keys().nth(1).unwrap(); assert!(subkey.binding_signature().hashed_area() .subpacket(SubpacketTag::KeyExpirationTime).is_none()); assert!(subkey.alive().is_err()); Ok(()) } /// When setting the primary key's validity period, we create a /// direct key signature. Check that this works even when the /// original certificate doesn't have a direct key signature. #[test] fn set_expiry_on_certificate_without_direct_signature() -> Result<()> { use crate::policy::StandardPolicy; let p = &StandardPolicy::new(); let (cert, _) = CertBuilder::general_purpose(None, Some("alice@example.org")) .set_validity_period(None) .generate()?; // Remove the direct key signatures. let cert = Cert::from_packets(Vec::from(cert) .into_iter() .filter(|p| { match p { Packet::Signature(s) if s.typ() == SignatureType::DirectKey => false, _ => true, } }))?; let vc = cert.with_policy(p, None)?; // Assert that the keys are not expired. for ka in vc.keys() { assert!(ka.alive().is_ok()); } // Make the primary key expire in a week. let t = time::SystemTime::now() + time::Duration::from_secs(7 * 24 * 60 * 60); let mut signer = vc .primary_key().key().clone().parts_into_secret()? .into_keypair()?; let sigs = vc.primary_key() .set_expiration_time(&mut signer, Some(t))?; assert!(sigs.iter().any(|s| { s.typ() == SignatureType::DirectKey })); let cert = cert.insert_packets(sigs)?; // Make sure the primary key *and* all subkeys expire in a // week: the subkeys inherit the KeyExpirationTime subpacket // from the direct key signature. for ka in cert.keys() { let ka = ka.with_policy(p, None)?; assert!(ka.alive().is_ok()); let ka = ka.with_policy(p, t + std::time::Duration::new(1, 0))?; assert!(ka.alive().is_err()); } Ok(()) } }