[][src]Struct sequoia_openpgp::cert::prelude::CertParser

pub struct CertParser<'a> { /* fields omitted */ }

An iterator over a sequence of certificates, i.e., an OpenPGP keyring.

The source of packets is a fallible iterator over Packets. In this way, it is possible to propagate parse errors.

A CertParser returns each TPK or TSK that it encounters. Its behavior can be modeled using a simple state machine.

In the first and initial state, it looks for the start of a certificate, a Public Key packet or a Secret Key packet. When it encounters such a packet it buffers it, and transitions to the second state. Any other packet or an error causes it to emit an error and stay in the same state. When the source of packets is exhausted, it enters the End state.

In the second state, it looks for packets that belong to a certificate's body. If it encounters a valid body packet, then it buffers it and stays in the same state. If it encounters the start of a certificate, then it emits the buffered certificate, buffers the packet, and stays in the same state. If it encounters an invalid packet (e.g., a Literal Data packet), it emits two items, the buffered certificate, and an error, and then it transitions back to the initial state. When the source of packets is exhausted, it emits the buffered certificate and enters the end state.

In the end state, it emits None.

                      Invalid Packet / Error
                    ,------------------------.
                    v                        |
   Not a      +---------+                +---------+
   Start  .-> | Looking | -------------> | Looking | <-. Cert
 of Cert  |   |   for   |     Start      |   for   |   | Body
  Packet  |   |  Start  |    of Cert     |  Cert   |   | Packet
 / Error  `-- | of Cert |     Packet     |  Body   | --'
              +---------+            .-> +---------+
                   |                 |      |  |
                   |                 `------'  |
                   |    Start of Cert Packet   |
                   |                           |
               EOF |         +-----+           | EOF
                    `------> | End | <---------'
                             +-----+
                              |  ^
                              `--'

The parser does not recurse into containers, thus when it encounters a container like a Compressed Data Packet, it will return an error even if the container contains a valid certificate.

The parser considers unknown packets to be valid body packets. (In a Cert, these show up as Unknown components.) The goal is to provide some future compatibility.

Example

Print information about all certificates in a keyring:

use sequoia_openpgp as openpgp;
use openpgp::parse::Parse;
use openpgp::parse::PacketParser;
use openpgp::cert::prelude::*;

let ppr = PacketParser::from_bytes(&keyring)?;
for certo in CertParser::from(ppr) {
    match certo {
        Ok(cert) => {
            println!("Key: {}", cert.fingerprint());
            for ua in cert.userids() {
                println!("  User ID: {}", ua.userid());
            }
        }
        Err(err) => {
            eprintln!("Error reading keyring: {}", err);
        }
    }
}

When an invalid packet is encountered, an error is returned and parsing continues:

use sequoia_openpgp as openpgp;
use openpgp::cert::prelude::*;
use openpgp::packet::prelude::*;
use openpgp::types::DataFormat;

let mut lit = Literal::new(DataFormat::Text);
lit.set_body(b"test".to_vec());

let (alice, _) =
      CertBuilder::general_purpose(None, Some("alice@example.org"))
      .generate()?;
let (bob, _) =
      CertBuilder::general_purpose(None, Some("bob@example.org"))
      .generate()?;

let mut packets : Vec<Packet> = Vec::new();
packets.extend(alice.clone());
packets.push(lit.clone().into());
packets.push(lit.clone().into());
packets.extend(bob.clone());

let r : Vec<Result<Cert>> = CertParser::from(packets).collect();
assert_eq!(r.len(), 4);
assert_eq!(r[0].as_ref().unwrap().fingerprint(), alice.fingerprint());
assert!(r[1].is_err());
assert!(r[2].is_err());
assert_eq!(r[3].as_ref().unwrap().fingerprint(), bob.fingerprint());

Methods

impl<'a> CertParser<'a>[src]

pub fn from_iter<I, J>(iter: I) -> Self where
    I: 'a + IntoIterator<Item = J>,
    J: 'a + Into<Result<Packet>>, 
[src]

Creates a CertParser from a Result<Packet> iterator.

Note: because we implement From<Packet> for Result<Packet>, it is possible to pass in an iterator over Packets.

Examples

From a Vec<Packet>:

use sequoia_openpgp as openpgp;
use openpgp::cert::prelude::*;
use openpgp::packet::prelude::*;

for certo in CertParser::from_iter(packets) {
    match certo {
        Ok(cert) => {
            println!("Key: {}", cert.fingerprint());
            for ua in cert.userids() {
                println!("  User ID: {}", ua.userid());
            }
        }
        Err(err) => {
            eprintln!("Error reading keyring: {}", err);
        }
    }
}

pub fn unvalidated_cert_filter<F: 'a>(self, filter: F) -> Self where
    F: Fn(&Cert, bool) -> bool
[src]

Filters the Certs prior to validation.

By default, the CertParser only returns valdiated Certs. Checking that a certificate's self-signatures are valid, however, is computationally expensive, and not always necessary. For example, when looking for a small number of certificates in a large keyring, most certificates can be immediately discarded. That is, it is more efficient to filter, validate, and double check, than to validate and filter. (It is necessary to double check, because the check might have been on an invalid part. For example, if searching for a key with a particular Key ID, a matching key might not have any self signatures.)

If the CertParser gave out unvalidated Certs, and provided an interface to validate them, then the caller could implement this check-validate-double-check pattern. Giving out unvalidated Certs, however, is dangerous: inevitably, a Cert will be used without having been validated in a context where it should have been.

This function avoids this class of bugs while still providing a mechanism to filter Certs prior to validation: the caller provides a callback that is invoked on the unvalidated Cert. If the callback returns true, then the parser validates the Cert, and invokes the callback a second time to make sure the Cert is really wanted. If the callback returns false, then the Cert is skipped.

Note: calling this function multiple times on a single CertParser will not replace the existing filter, but install multiple filters.

Examples

use sequoia_openpgp as openpgp;
use openpgp::cert::prelude::*;

for certr in CertParser::from(ppr)
    .unvalidated_cert_filter(|cert, _| {
        for component in cert.keys() {
            if component.key().keyid() == some_keyid {
                return true;
            }
        }
        false
    })
{
    match certr {
        Ok(cert) => {
            // The Cert contains the subkey.
        }
        Err(err) => {
            eprintln!("Error reading keyring: {}", err);
        }
    }
}

Trait Implementations

impl<'a> Parse<'a, CertParser<'a>> for CertParser<'a>[src]

fn from_reader<R: 'a + Read>(reader: R) -> Result<Self>[src]

Initializes a CertParser from a Reader.

fn from_file<P: AsRef<Path>>(path: P) -> Result<Self>[src]

Initializes a CertParser from a File.

fn from_bytes<D: AsRef<[u8]> + ?Sized>(data: &'a D) -> Result<Self>[src]

Initializes a CertParser from a byte string.

impl<'a> From<PacketParserResult<'a>> for CertParser<'a>[src]

fn from(ppr: PacketParserResult<'a>) -> Self[src]

Initializes a CertParser from a PacketParser.

impl<'a> From<Vec<Result<Packet, Error>>> for CertParser<'a>[src]

impl<'a> From<Vec<Packet>> for CertParser<'a>[src]

impl<'a> Iterator for CertParser<'a>[src]

type Item = Result<Cert>

The type of the elements being iterated over.

fn size_hint(&self) -> (usize, Option<usize>)
1.0.0
[src]

Returns the bounds on the remaining length of the iterator. Read more

fn count(self) -> usize
1.0.0
[src]

Consumes the iterator, counting the number of iterations and returning it. Read more

fn last(self) -> Option<Self::Item>
1.0.0
[src]

Consumes the iterator, returning the last element. Read more

fn nth(&mut self, n: usize) -> Option<Self::Item>
1.0.0
[src]

Returns the nth element of the iterator. Read more

fn step_by(self, step: usize) -> StepBy<Self>
1.28.0
[src]

Creates an iterator starting at the same point, but stepping by the given amount at each iteration. Read more

fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter> where
    U: IntoIterator<Item = Self::Item>, 
1.0.0
[src]

Takes two iterators and creates a new iterator over both in sequence. Read more

fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter> where
    U: IntoIterator
1.0.0
[src]

'Zips up' two iterators into a single iterator of pairs. Read more

fn map<B, F>(self, f: F) -> Map<Self, F> where
    F: FnMut(Self::Item) -> B, 
1.0.0
[src]

Takes a closure and creates an iterator which calls that closure on each element. Read more

fn for_each<F>(self, f: F) where
    F: FnMut(Self::Item), 
1.21.0
[src]

Calls a closure on each element of an iterator. Read more

fn filter<P>(self, predicate: P) -> Filter<Self, P> where
    P: FnMut(&Self::Item) -> bool
1.0.0
[src]

Creates an iterator which uses a closure to determine if an element should be yielded. Read more

fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F> where
    F: FnMut(Self::Item) -> Option<B>, 
1.0.0
[src]

Creates an iterator that both filters and maps. Read more

fn enumerate(self) -> Enumerate<Self>
1.0.0
[src]

Creates an iterator which gives the current iteration count as well as the next value. Read more

fn peekable(self) -> Peekable<Self>
1.0.0
[src]

Creates an iterator which can use peek to look at the next element of the iterator without consuming it. Read more

fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where
    P: FnMut(&Self::Item) -> bool
1.0.0
[src]

Creates an iterator that [skip]s elements based on a predicate. Read more

fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P> where
    P: FnMut(&Self::Item) -> bool
1.0.0
[src]

Creates an iterator that yields elements based on a predicate. Read more

fn skip(self, n: usize) -> Skip<Self>
1.0.0
[src]

Creates an iterator that skips the first n elements. Read more

fn take(self, n: usize) -> Take<Self>
1.0.0
[src]

Creates an iterator that yields its first n elements. Read more

fn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F> where
    F: FnMut(&mut St, Self::Item) -> Option<B>, 
1.0.0
[src]

An iterator adaptor similar to [fold] that holds internal state and produces a new iterator. Read more

fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> where
    F: FnMut(Self::Item) -> U,
    U: IntoIterator
1.0.0
[src]

Creates an iterator that works like map, but flattens nested structure. Read more

fn flatten(self) -> Flatten<Self> where
    Self::Item: IntoIterator
1.29.0
[src]

Creates an iterator that flattens nested structure. Read more

fn fuse(self) -> Fuse<Self>
1.0.0
[src]

Creates an iterator which ends after the first [None]. Read more

fn inspect<F>(self, f: F) -> Inspect<Self, F> where
    F: FnMut(&Self::Item), 
1.0.0
[src]

Do something with each element of an iterator, passing the value on. Read more

fn by_ref(&mut self) -> &mut Self
1.0.0
[src]

Borrows an iterator, rather than consuming it. Read more

#[must_use = "if you really need to exhaust the iterator, consider `.for_each(drop)` instead"]
fn collect<B>(self) -> B where
    B: FromIterator<Self::Item>, 
1.0.0
[src]

Transforms an iterator into a collection. Read more

fn partition<B, F>(self, f: F) -> (B, B) where
    B: Default + Extend<Self::Item>,
    F: FnMut(&Self::Item) -> bool
1.0.0
[src]

Consumes an iterator, creating two collections from it. Read more

fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R where
    F: FnMut(B, Self::Item) -> R,
    R: Try<Ok = B>, 
1.27.0
[src]

An iterator method that applies a function as long as it returns successfully, producing a single, final value. Read more

fn try_for_each<F, R>(&mut self, f: F) -> R where
    F: FnMut(Self::Item) -> R,
    R: Try<Ok = ()>, 
1.27.0
[src]

An iterator method that applies a fallible function to each item in the iterator, stopping at the first error and returning that error. Read more

fn fold<B, F>(self, init: B, f: F) -> B where
    F: FnMut(B, Self::Item) -> B, 
1.0.0
[src]

An iterator method that applies a function, producing a single, final value. Read more

fn all<F>(&mut self, f: F) -> bool where
    F: FnMut(Self::Item) -> bool
1.0.0
[src]

Tests if every element of the iterator matches a predicate. Read more

fn any<F>(&mut self, f: F) -> bool where
    F: FnMut(Self::Item) -> bool
1.0.0
[src]

Tests if any element of the iterator matches a predicate. Read more

fn find<P>(&mut self, predicate: P) -> Option<Self::Item> where
    P: FnMut(&Self::Item) -> bool
1.0.0
[src]

Searches for an element of an iterator that satisfies a predicate. Read more

fn find_map<B, F>(&mut self, f: F) -> Option<B> where
    F: FnMut(Self::Item) -> Option<B>, 
1.30.0
[src]

Applies function to the elements of iterator and returns the first non-none result. Read more

fn position<P>(&mut self, predicate: P) -> Option<usize> where
    P: FnMut(Self::Item) -> bool
1.0.0
[src]

Searches for an element in an iterator, returning its index. Read more

fn rposition<P>(&mut self, predicate: P) -> Option<usize> where
    P: FnMut(Self::Item) -> bool,
    Self: ExactSizeIterator + DoubleEndedIterator
1.0.0
[src]

Searches for an element in an iterator from the right, returning its index. Read more

fn max(self) -> Option<Self::Item> where
    Self::Item: Ord
1.0.0
[src]

Returns the maximum element of an iterator. Read more

fn min(self) -> Option<Self::Item> where
    Self::Item: Ord
1.0.0
[src]

Returns the minimum element of an iterator. Read more

fn max_by_key<B, F>(self, f: F) -> Option<Self::Item> where
    B: Ord,
    F: FnMut(&Self::Item) -> B, 
1.6.0
[src]

Returns the element that gives the maximum value from the specified function. Read more

fn max_by<F>(self, compare: F) -> Option<Self::Item> where
    F: FnMut(&Self::Item, &Self::Item) -> Ordering
1.15.0
[src]

Returns the element that gives the maximum value with respect to the specified comparison function. Read more

fn min_by_key<B, F>(self, f: F) -> Option<Self::Item> where
    B: Ord,
    F: FnMut(&Self::Item) -> B, 
1.6.0
[src]

Returns the element that gives the minimum value from the specified function. Read more

fn min_by<F>(self, compare: F) -> Option<Self::Item> where
    F: FnMut(&Self::Item, &Self::Item) -> Ordering
1.15.0
[src]

Returns the element that gives the minimum value with respect to the specified comparison function. Read more

fn rev(self) -> Rev<Self> where
    Self: DoubleEndedIterator
1.0.0
[src]

Reverses an iterator's direction. Read more

fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB) where
    FromA: Default + Extend<A>,
    FromB: Default + Extend<B>,
    Self: Iterator<Item = (A, B)>, 
1.0.0
[src]

Converts an iterator of pairs into a pair of containers. Read more

fn copied<'a, T>(self) -> Copied<Self> where
    Self: Iterator<Item = &'a T>,
    T: 'a + Copy
[src]

🔬 This is a nightly-only experimental API. (iter_copied)

Creates an iterator which copies all of its elements. Read more

fn cloned<'a, T>(self) -> Cloned<Self> where
    Self: Iterator<Item = &'a T>,
    T: 'a + Clone
1.0.0
[src]

Creates an iterator which [clone]s all of its elements. Read more

fn cycle(self) -> Cycle<Self> where
    Self: Clone
1.0.0
[src]

Repeats an iterator endlessly. Read more

fn sum<S>(self) -> S where
    S: Sum<Self::Item>, 
1.11.0
[src]

Sums the elements of an iterator. Read more

fn product<P>(self) -> P where
    P: Product<Self::Item>, 
1.11.0
[src]

Iterates over the entire iterator, multiplying all the elements Read more

fn cmp<I>(self, other: I) -> Ordering where
    I: IntoIterator<Item = Self::Item>,
    Self::Item: Ord
1.5.0
[src]

Lexicographically compares the elements of this Iterator with those of another. Read more

fn partial_cmp<I>(self, other: I) -> Option<Ordering> where
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>, 
1.5.0
[src]

Lexicographically compares the elements of this Iterator with those of another. Read more

fn eq<I>(self, other: I) -> bool where
    I: IntoIterator,
    Self::Item: PartialEq<<I as IntoIterator>::Item>, 
1.5.0
[src]

Determines if the elements of this Iterator are equal to those of another. Read more

fn ne<I>(self, other: I) -> bool where
    I: IntoIterator,
    Self::Item: PartialEq<<I as IntoIterator>::Item>, 
1.5.0
[src]

Determines if the elements of this Iterator are unequal to those of another. Read more

fn lt<I>(self, other: I) -> bool where
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>, 
1.5.0
[src]

Determines if the elements of this Iterator are lexicographically less than those of another. Read more

fn le<I>(self, other: I) -> bool where
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>, 
1.5.0
[src]

Determines if the elements of this Iterator are lexicographically less or equal to those of another. Read more

fn gt<I>(self, other: I) -> bool where
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>, 
1.5.0
[src]

Determines if the elements of this Iterator are lexicographically greater than those of another. Read more

fn ge<I>(self, other: I) -> bool where
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>, 
1.5.0
[src]

Determines if the elements of this Iterator are lexicographically greater than or equal to those of another. Read more

fn is_sorted(self) -> bool where
    Self::Item: PartialOrd<Self::Item>, 
[src]

🔬 This is a nightly-only experimental API. (is_sorted)

new API

Checks if the elements of this iterator are sorted. Read more

fn is_sorted_by<F>(self, compare: F) -> bool where
    F: FnMut(&Self::Item, &Self::Item) -> Option<Ordering>, 
[src]

🔬 This is a nightly-only experimental API. (is_sorted)

new API

Checks if the elements of this iterator are sorted using the given comparator function. Read more

fn is_sorted_by_key<F, K>(self, f: F) -> bool where
    F: FnMut(&Self::Item) -> K,
    K: PartialOrd<K>, 
[src]

🔬 This is a nightly-only experimental API. (is_sorted)

new API

Checks if the elements of this iterator are sorted using the given key extraction function. Read more

impl<'a> Default for CertParser<'a>[src]

Auto Trait Implementations

impl<'a> !Send for CertParser<'a>

impl<'a> !Sync for CertParser<'a>

Blanket Implementations

impl<T> From for T[src]

impl<I> IntoIterator for I where
    I: Iterator
[src]

type Item = <I as Iterator>::Item

The type of the elements being iterated over.

type IntoIter = I

Which kind of iterator are we turning this into?

impl<T, U> Into for T where
    U: From<T>, 
[src]

impl<T, U> TryFrom for T where
    U: Into<T>, 
[src]

type Error = Infallible

The type returned in the event of a conversion error.

impl<T> Borrow for T where
    T: ?Sized
[src]

impl<T> BorrowMut for T where
    T: ?Sized
[src]

impl<T> Any for T where
    T: 'static + ?Sized
[src]

impl<T, U> TryInto for T where
    U: TryFrom<T>, 
[src]

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.