Struct Parameters 

pub struct Parameters<'a> { /* private fields */ }

Original PSS schema values, not algorithm support or signature validity.

Implementations

impl<'a> Parameters<'a>

pub fn profile<W: Work>(&self, execution: &W) -> Result<Resolution<Profile<'a>>>

Interprets already decoded fields without a second PSS schema pass.

Written digests reuse the shared digest resolver (SHA-1/SHA-2/SHA3); schema defaults impose SHA-1 without a fabricated identifier. MGF1 may use a different digest from the message. Unknown digests/mask functions or nonnegative trailers other than 1 are Unsupported, never a key mismatch. Recognition does not promise backend support. Negative trailers and invalid known digest parameters are located malformed errors. Original fields remain available for inspection. Strict versus recoverable DER spelling is determined by the caller’s earlier pss::read or pss::inspect; projection does not erase faults or turn an inspection result into conforming evidence.

Errors

Located malformed fields or terminal source/current resource refusal.

Examples

use std::sync::Arc;
use structured_asn1::{Parser, digest::Resolution, memory::{Memory, MemoryAccount}};
use structured_pkix::algorithm::{self, digest, pss};
let parser = Parser::ber(Memory::new(Arc::new(MemoryAccount::new(4096, 4096))));
// id-RSASSA-PSS, empty parameters: SHA1, MGF1-SHA1, salt 20, trailer 1.
let bytes = b"\x30\x0d\x06\x09\x2a\x86\x48\x86\xf7\x0d\x01\x01\x0a\x30\x00";
let mut reader = parser.read(bytes, 400).unwrap();
let element = reader.next_element().unwrap().unwrap();
let identifier = algorithm::read(&reader, &element, "signatureAlgorithm")?;
let fields = pss::read(identifier, parser.memory())?.unwrap();
let current = Memory::new(Arc::new(MemoryAccount::new(0, 4096)));
let Resolution::Supported(profile) = fields.profile(&current)? else { panic!("PSS") };
assert_eq!(profile.hash(), digest::Algorithm::Sha1);
assert_eq!(profile.salt().as_u64(), Some(20));
assert!(profile.allows(&profile, &current)?);

impl<'a> Parameters<'a>

pub fn element(self) -> Element<'a>

Complete original parameter SEQUENCE, without copies or normalization.

pub fn hash(self) -> Option<Written<'a, AlgorithmIdentifier<'a>>>

Written hash identifier; None is the schema’s SHA-1 default.

pub fn mask(self) -> Mask<'a>

Mask identity and original MGF1 hash, including omitted default.

pub fn salt(self) -> Number<'a>

Salt octet length (default 20, independently of the selected hash). Its applicability as an exact signature length or key minimum is a caller role decision (RFC4055 §3.3); no backend maximum is imposed here.

pub fn trailer(self) -> Number<'a>

Trailer number (default 1). Other numbers are retained for inspection; RFC8017 A.2.3 defines support only for trailer 1, not other schemes.

Trait Implementations

impl<'a> Clone for Parameters<'a>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a> Copy for Parameters<'a>

impl<'a> Debug for Parameters<'a>

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

Formats the value using the given formatter.