yubikey v0.8.0 (#518)

Replaces unwraps with `Error::AlgorithmError`

.github/workflows/ci.yml

@@ -82,7 +82,7 @@ jobs:
       - uses: actions-rs/toolchain@v1
         with:
           profile: minimal
-          toolchain: 1.65.0
+          toolchain: 1.71.0
           components: clippy
           override: true
       - run: sudo apt-get install libpcsclite-dev

CHANGELOG.md

@@ -4,11 +4,11 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## Unreleased
+## 0.8.0 (2023-08-15)
 ### Added
-- `YubiKey::disconnect`
+- `impl Debug for {Context, YubiKey}` ([#457])
-- `impl Debug for {Context, YubiKey}`
+- `YubiKey::disconnect` ([#462])
-- `Error::AppletNotFound`
+- `Error::AppletNotFound` ([#476])
 
 ### Changed
 - `Reader::open` now returns `Error::AppletNotFound` instead of `Error::Generic`
@@ -18,11 +18,35 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `Reader::open` now avoids resetting the card if an error occurs (equivalent to
   calling `YubiKey::disconnect(pcsc::Disposition::LeaveCard)` if `Reader::open`
   succeeds).
+- Raise minimum `pcsc` version to 2.3.1 and remove workaround ([#478])
+- Bump asymmetric crypto dependencies; MSRV 1.65 ([#490])
+  - `elliptic-curve` v0.13
+  - `k256` v0.13
+  - `p256` v0.13
+  - `p384` v0.13
+  - `pbkdf2` v0.12
+  - `rsa` v0.9 ([#502])
+  - `signature` v2
+- Use `x509-cert` certificate builder ([#495])
+- Make `RsaKeyData::new` fallible ([#517])
 
 ### Fixed
 - `StatusWords::code` now returns the correct code (including embedded `tries`
   count) for `StatusWords::VerifyFailError`. Previously the returned code lost
   information and was not round-trip compatible with `StatusWords::from(u16)`.
+- Parsing of serial numbers ([#466])
+- Make `YubiKey::open()` more robust ([#504])
+
+[#457]: https://github.com/iqlusioninc/yubikey.rs/pull/457
+[#462]: https://github.com/iqlusioninc/yubikey.rs/pull/462
+[#466]: https://github.com/iqlusioninc/yubikey.rs/pull/466
+[#476]: https://github.com/iqlusioninc/yubikey.rs/pull/476
+[#478]: https://github.com/iqlusioninc/yubikey.rs/pull/478
+[#490]: https://github.com/iqlusioninc/yubikey.rs/pull/490
+[#495]: https://github.com/iqlusioninc/yubikey.rs/pull/495
+[#502]: https://github.com/iqlusioninc/yubikey.rs/pull/502
+[#504]: https://github.com/iqlusioninc/yubikey.rs/pull/504
+[#517]: https://github.com/iqlusioninc/yubikey.rs/pull/517
 
 ## 0.7.0 (2022-11-14)
 ### Added

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "yubikey"
-version = "0.8.0-pre.0"
+version = "0.8.0"
 description = """
 Pure Rust cross-platform host-side driver for YubiKey devices from Yubico with
 support for hardware-backed public-key decryption and digital signatures using
@@ -19,10 +19,11 @@ rust-version = "1.65"
 [workspace]
 members = [".", "cli"]
 
+[workspace.dependencies]
+x509-cert = { version = "0.2.3", features = [ "builder", "hazmat" ] }
+
 [dependencies]
-chrono = "0.4.23"
+der = "0.7.1"
-cookie-factory = "0.3"
-der-parser = "8"
 des = "0.8"
 elliptic-curve = "0.13"
 hex = { package = "base16ct", version = "0.2", features = ["alloc"] }
@@ -32,19 +33,20 @@ nom = "7"
 num-bigint-dig = { version = "0.8", features = ["rand"] }
 num-traits = "0.2"
 num-integer = "0.1"
+ecdsa = { version = "0.16.7", features = ["digest", "pem"] }
 p256 = "0.13"
 p384 = "0.13"
 pbkdf2 = { version = "0.12", default-features = false, features = ["hmac"] }
 pcsc = "2.3.1"
 rand_core = { version = "0.6", features = ["std"] }
-rsa = "=0.9.0-pre.0"
+rsa = { version = "0.9.2", features = ["sha2"] }
 secrecy = "0.8"
 sha1 = { version = "0.10", features = ["oid"] }
 sha2 = { version = "0.10", features = ["oid"] }
+signature = "2"
 subtle = "2"
 uuid = { version = "1.2", features = ["v4"] }
-x509 = "0.2"
+x509-cert.workspace = true
-x509-parser = "0.14"
 zeroize = "1"
 
 [dev-dependencies]

cli/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "yubikey-cli"
-version = "0.7.0"
+version = "0.8.0-pre"
 description = """
 Command-line interface for performing encryption and signing using RSA/ECC keys
 stored on YubiKey devices.
@@ -22,5 +22,5 @@ log = "0.4"
 once_cell = "1"
 sha2 = "0.10"
 termcolor = "1"
-x509-parser = "0.14"
+x509-cert.workspace = true
-yubikey = { version = "0.8.0-pre.0", path = ".." }
+yubikey = { version = "0.8", path = ".." }

cli/src/terminal.rs

@@ -9,7 +9,7 @@ use std::{
     sync::Mutex,
 };
 use termcolor::{Color, ColorChoice, ColorSpec, StandardStream, StandardStreamLock, WriteColor};
-use x509_parser::parse_x509_certificate;
+use x509_cert::der::Encode;
 use yubikey::{certificate::Certificate, piv::*, YubiKey};
 
 /// Print a success status message (in green if colors are enabled)
@@ -180,52 +180,30 @@ pub fn print_cert_info(
             return Ok(());
         }
     };
-    let buf = cert.into_buffer();
+    let cert = &cert.cert;
 
-    if !buf.is_empty() {
+    let fingerprint = Sha256::digest(cert.to_der().unwrap());
-        let fingerprint = Sha256::digest(&buf);
+    let slot_id: u8 = slot.into();
-        let slot_id: u8 = slot.into();
+    print_cert_attr(stream, "Slot", format!("{:x}", slot_id))?;
-        print_cert_attr(stream, "Slot", format!("{:x}", slot_id))?;
+    print_cert_attr(
-        match parse_x509_certificate(&buf) {
+        stream,
-            Ok((_rem, cert)) => {
+        "Algorithm",
-                print_cert_attr(
+        cert.tbs_certificate.subject_public_key_info.algorithm.oid,
-                    stream,
+    )?;
-                    "Algorithm",
-                    cert.tbs_certificate.subject_pki.algorithm.algorithm,
-                )?;
 
-                print_cert_attr(stream, "Subject", cert.tbs_certificate.subject)?;
+    print_cert_attr(stream, "Subject", &cert.tbs_certificate.subject)?;
-                print_cert_attr(stream, "Issuer", cert.tbs_certificate.issuer)?;
+    print_cert_attr(stream, "Issuer", &cert.tbs_certificate.issuer)?;
-                print_cert_attr(
+    print_cert_attr(
-                    stream,
+        stream,
-                    "Fingerprint",
+        "Fingerprint",
-                    &hex::upper::encode_string(&fingerprint),
+        &hex::upper::encode_string(&fingerprint),
-                )?;
+    )?;
-                print_cert_attr(
+    print_cert_attr(
-                    stream,
+        stream,
-                    "Not Before",
+        "Not Before",
-                    cert.tbs_certificate
+        cert.tbs_certificate.validity.not_before,
-                        .validity
+    )?;
-                        .not_before
+    print_cert_attr(stream, "Not After", cert.tbs_certificate.validity.not_after)?;
-                        .to_rfc2822()
-                        .unwrap(),
-                )?;
-                print_cert_attr(
-                    stream,
-                    "Not After",
-                    cert.tbs_certificate
-                        .validity
-                        .not_after
-                        .to_rfc2822()
-                        .unwrap(),
-                )?;
-            }
-            _ => {
-                println!("Failed to parse certificate");
-                return Ok(());
-            }
-        };
-    }
 
     Ok(())
 }

src/cccid.rs

@@ -30,7 +30,7 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-use crate::{Error, Result, YubiKey};
+use crate::{Result, YubiKey};
 use rand_core::{OsRng, RngCore};
 use std::fmt::{self, Debug, Display};
 
@@ -48,6 +48,7 @@ const OBJ_CAPABILITY: u32 = 0x005f_c107;
 ///  - 0xff == Manufacturer ID (dummy)
 ///  - 0x02 == Card type (javaCard)
 ///  - next 14 bytes: card ID
+#[allow(dead_code)]
 const CCC_TMPL: &[u8] = &[
     0xf0, 0x15, 0xa0, 0x00, 0x00, 0x01, 0x16, 0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf1, 0x01, 0x21, 0xf2, 0x01, 0x21, 0xf3, 0x00, 0xf4,
@@ -90,17 +91,11 @@ impl CccId {
     pub fn get(yubikey: &mut YubiKey) -> Result<Self> {
         let txn = yubikey.begin_transaction()?;
         let response = txn.fetch_object(OBJ_CAPABILITY)?;
-
+        Ok(response[..Self::BYTE_SIZE].try_into().map(Self)?)
-        if response.len() != CCC_TMPL.len() {
-            return Err(Error::GenericError);
-        }
-
-        Ok(Self(response[..Self::BYTE_SIZE].try_into().unwrap()))
     }
 
     /// Set Cardholder Capability Container (CCC) ID
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn set(&self, yubikey: &mut YubiKey) -> Result<()> {
         let mut buf = CCC_TMPL.to_vec();
         buf[0..self.0.len()].copy_from_slice(&self.0);

src/certificate.rs

@@ -33,90 +33,27 @@
 use crate::{
     consts::CB_OBJ_MAX,
     error::{Error, Result},
-    piv::{sign_data, AlgorithmId, SlotId},
+    piv::SlotId,
     serialization::*,
     transaction::Transaction,
     yubikey::YubiKey,
     Buffer,
 };
-use chrono::{DateTime, Utc};
-use elliptic_curve::sec1::EncodedPoint as EcPublicKey;
 use log::error;
-use num_bigint_dig::BigUint;
+use x509_cert::{
-use p256::NistP256;
+    builder::{Builder, CertificateBuilder, Profile},
-use p384::NistP384;
+    der::{self, referenced::OwnedToRef, Decode, Encode},
-use rsa::{PublicKeyParts, RsaPublicKey};
+    name::Name,
-use sha2::{Digest, Sha256};
+    serial_number::SerialNumber,
-use std::fmt::Display;
+    spki::{SubjectPublicKeyInfoOwned, SubjectPublicKeyInfoRef},
-use std::{fmt, ops::DerefMut};
+    time::Validity,
-use x509::{der::Oid, RelativeDistinguishedName};
+};
-use x509_parser::{parse_x509_certificate, x509::SubjectPublicKeyInfo};
 use zeroize::Zeroizing;
 
-// TODO: Make these der_parser::oid::Oid constants when it has const fn support.
-const OID_RSA_ENCRYPTION: &str = "1.2.840.113549.1.1.1";
-const OID_EC_PUBLIC_KEY: &str = "1.2.840.10045.2.1";
-const OID_NIST_P256: &str = "1.2.840.10045.3.1.7";
-const OID_NIST_P384: &str = "1.3.132.0.34";
-
 const TAG_CERT: u8 = 0x70;
 const TAG_CERT_COMPRESS: u8 = 0x71;
 const TAG_CERT_LRC: u8 = 0xFE;
 
-/// A serial number for a [`Certificate`].
-#[derive(Clone, Debug)]
-pub struct Serial(BigUint);
-
-impl From<BigUint> for Serial {
-    fn from(num: BigUint) -> Serial {
-        Serial(num)
-    }
-}
-
-impl From<[u8; 20]> for Serial {
-    fn from(bytes: [u8; 20]) -> Serial {
-        Serial(BigUint::from_bytes_be(&bytes))
-    }
-}
-
-impl TryFrom<&[u8]> for Serial {
-    type Error = Error;
-
-    fn try_from(bytes: &[u8]) -> Result<Serial> {
-        if bytes.len() <= 20 {
-            Ok(Serial(BigUint::from_bytes_be(bytes)))
-        } else {
-            Err(Error::ParseError)
-        }
-    }
-}
-
-impl Serial {
-    fn to_bytes(&self) -> Vec<u8> {
-        self.0.to_bytes_be()
-    }
-    /// Returns itself formatted as x509 compatible hex string
-    pub fn as_x509_hex(&self) -> String {
-        let data = self.to_bytes();
-        let raw_hex_string = format!("{:02X?}", data);
-        raw_hex_string
-            .replace(", ", ":")
-            .replace([']', '['], "")
-            .to_lowercase()
-    }
-    /// Returns itself formatted as x509 compatible int string
-    pub fn as_x509_int(&self) -> String {
-        let Serial(buint) = self;
-        format!("{}", buint)
-    }
-}
-
-impl Display for Serial {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.write_str(&self.as_x509_hex())
-    }
-}
-
 /// Information about how a [`Certificate`] is stored within a YubiKey.
 #[derive(Clone, Copy, Debug, Eq, PartialEq)]
 pub enum CertInfo {
@@ -148,210 +85,11 @@ impl From<CertInfo> for u8 {
     }
 }
 
-impl x509::AlgorithmIdentifier for AlgorithmId {
-    type AlgorithmOid = &'static [u64];
-
-    fn algorithm(&self) -> Self::AlgorithmOid {
-        match self {
-            // RSA encryption
-            AlgorithmId::Rsa1024 | AlgorithmId::Rsa2048 => &[1, 2, 840, 113_549, 1, 1, 1],
-            // EC Public Key
-            AlgorithmId::EccP256 | AlgorithmId::EccP384 => &[1, 2, 840, 10045, 2, 1],
-        }
-    }
-
-    fn parameters<W: std::io::Write>(
-        &self,
-        w: cookie_factory::WriteContext<W>,
-    ) -> cookie_factory::GenResult<W> {
-        use x509::der::write::der_oid;
-
-        // From [RFC 5480](https://tools.ietf.org/html/rfc5480#section-2.1.1):
-        // ```text
-        // ECParameters ::= CHOICE {
-        //   namedCurve         OBJECT IDENTIFIER
-        //   -- implicitCurve   NULL
-        //   -- specifiedCurve  SpecifiedECDomain
-        // }
-        // ```
-        match self {
-            AlgorithmId::EccP256 => der_oid(&[1, 2, 840, 10045, 3, 1, 7][..])(w),
-            AlgorithmId::EccP384 => der_oid(&[1, 3, 132, 0, 34][..])(w),
-            _ => Ok(w),
-        }
-    }
-}
-
-/// Information about a public key within a [`Certificate`].
-#[derive(Clone, Eq, PartialEq)]
-pub enum PublicKeyInfo {
-    /// RSA keys
-    Rsa {
-        /// RSA algorithm
-        algorithm: AlgorithmId,
-
-        /// Public key
-        pubkey: RsaPublicKey,
-    },
-
-    /// EC P-256 keys
-    EcP256(EcPublicKey<NistP256>),
-
-    /// EC P-384 keys
-    EcP384(EcPublicKey<NistP384>),
-}
-
-impl fmt::Debug for PublicKeyInfo {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "PublicKeyInfo({:?})", self.algorithm())
-    }
-}
-
-impl PublicKeyInfo {
-    fn parse(subject_pki: &SubjectPublicKeyInfo<'_>) -> Result<Self> {
-        match subject_pki.algorithm.algorithm.to_string().as_str() {
-            OID_RSA_ENCRYPTION => {
-                let pubkey = read_pki::rsa_pubkey(&subject_pki.subject_public_key.data)?;
-
-                Ok(PublicKeyInfo::Rsa {
-                    algorithm: match pubkey.n().bits() {
-                        1024 => AlgorithmId::Rsa1024,
-                        2048 => AlgorithmId::Rsa2048,
-                        _ => return Err(Error::AlgorithmError),
-                    },
-                    pubkey,
-                })
-            }
-            OID_EC_PUBLIC_KEY => {
-                let key_bytes = &subject_pki.subject_public_key.data;
-                let algorithm_parameters = subject_pki
-                    .algorithm
-                    .parameters
-                    .as_ref()
-                    .ok_or(Error::InvalidObject)?;
-
-                match read_pki::ec_parameters(algorithm_parameters)? {
-                    AlgorithmId::EccP256 => EcPublicKey::<NistP256>::from_bytes(key_bytes)
-                        .map(PublicKeyInfo::EcP256)
-                        .map_err(|_| Error::InvalidObject),
-                    AlgorithmId::EccP384 => EcPublicKey::<NistP384>::from_bytes(key_bytes)
-                        .map(PublicKeyInfo::EcP384)
-                        .map_err(|_| Error::InvalidObject),
-                    _ => Err(Error::AlgorithmError),
-                }
-            }
-            _ => Err(Error::InvalidObject),
-        }
-    }
-
-    /// Returns the algorithm that this public key can be used with.
-    pub fn algorithm(&self) -> AlgorithmId {
-        match self {
-            PublicKeyInfo::Rsa { algorithm, .. } => *algorithm,
-            PublicKeyInfo::EcP256(_) => AlgorithmId::EccP256,
-            PublicKeyInfo::EcP384(_) => AlgorithmId::EccP384,
-        }
-    }
-}
-
-impl x509::SubjectPublicKeyInfo for PublicKeyInfo {
-    type AlgorithmId = AlgorithmId;
-    type SubjectPublicKey = Vec<u8>;
-
-    fn algorithm_id(&self) -> AlgorithmId {
-        self.algorithm()
-    }
-
-    fn public_key(&self) -> Vec<u8> {
-        match self {
-            PublicKeyInfo::Rsa { pubkey, .. } => {
-                cookie_factory::gen_simple(write_pki::rsa_pubkey(pubkey), vec![])
-                    .expect("can write to Vec")
-            }
-            PublicKeyInfo::EcP256(pubkey) => pubkey.as_bytes().to_vec(),
-            PublicKeyInfo::EcP384(pubkey) => pubkey.as_bytes().to_vec(),
-        }
-    }
-}
-
-/// Digest algorithms.
-///
-/// See RFC 4055 and RFC 8017.
-enum DigestId {
-    /// Secure Hash Algorithm 256 (SHA256)
-    Sha256,
-}
-
-impl x509::AlgorithmIdentifier for DigestId {
-    type AlgorithmOid = &'static [u64];
-
-    fn algorithm(&self) -> Self::AlgorithmOid {
-        match self {
-            // See https://tools.ietf.org/html/rfc4055#section-2.1
-            DigestId::Sha256 => &[2, 16, 840, 1, 101, 3, 4, 2, 1],
-        }
-    }
-
-    fn parameters<W: std::io::Write>(
-        &self,
-        w: cookie_factory::WriteContext<W>,
-    ) -> cookie_factory::GenResult<W> {
-        // Parameters are an explicit NULL
-        // See https://tools.ietf.org/html/rfc8017#appendix-A.2.4
-        x509::der::write::der_null()(w)
-    }
-}
-
-enum SignatureId {
-    /// Public-Key Cryptography Standards (PKCS) #1 version 1.5 signature algorithm with
-    /// Secure Hash Algorithm 256 (SHA256) and Rivest, Shamir and Adleman (RSA) encryption
-    ///
-    /// See RFC 4055 and RFC 8017.
-    Sha256WithRsaEncryption,
-
-    /// Elliptic Curve Digital Signature Algorithm (DSA) coupled with the Secure Hash
-    /// Algorithm 256 (SHA256) algorithm
-    ///
-    /// See RFC 5758.
-    EcdsaWithSha256,
-}
-
-impl x509::AlgorithmIdentifier for SignatureId {
-    type AlgorithmOid = &'static [u64];
-
-    fn algorithm(&self) -> Self::AlgorithmOid {
-        match self {
-            SignatureId::Sha256WithRsaEncryption => &[1, 2, 840, 113_549, 1, 1, 11],
-            SignatureId::EcdsaWithSha256 => &[1, 2, 840, 10045, 4, 3, 2],
-        }
-    }
-
-    fn parameters<W: std::io::Write>(
-        &self,
-        w: cookie_factory::WriteContext<W>,
-    ) -> cookie_factory::GenResult<W> {
-        // No parameters for any SignatureId
-        Ok(w)
-    }
-}
-
 /// Certificates
 #[derive(Clone, Debug)]
 pub struct Certificate {
-    serial: Serial,
+    /// Inner certificate
-    #[allow(dead_code)]
+    pub cert: x509_cert::Certificate,
-    issuer: String,
-    subject: String,
-    subject_pki: PublicKeyInfo,
-    data: Buffer,
-}
-
-impl<'a> TryFrom<&'a [u8]> for Certificate {
-    type Error = Error;
-
-    fn try_from(bytes: &'a [u8]) -> Result<Self> {
-        Self::from_bytes(bytes.to_vec())
-    }
 }
 
 impl Certificate {
@@ -360,112 +98,35 @@ impl Certificate {
     ///
     /// `extensions` is optional; if empty, no extensions will be included. Due to the
     /// need for an `O: Oid` type parameter, users who do not have any extensions should
-    /// use the workaround `let extensions: &[x509::Extension<'_, &[u64]>] = &[];`.
+    /// use the workaround `let extensions: &[x509_cert::Extension<'_, &[u64]>] = &[];`.
-    pub fn generate_self_signed<O: Oid>(
+    pub fn generate_self_signed<F, KT: yubikey_signer::KeyType>(
         yubikey: &mut YubiKey,
         key: SlotId,
-        serial: impl Into<Serial>,
+        serial: SerialNumber,
-        not_after: Option<DateTime<Utc>>,
+        validity: Validity,
-        subject: &[RelativeDistinguishedName<'_>],
+        subject: Name,
-        subject_pki: PublicKeyInfo,
+        subject_pki: SubjectPublicKeyInfoOwned,
-        extensions: &[x509::Extension<'_, O>],
+        extensions: F,
-    ) -> Result<Self> {
+    ) -> Result<Self>
-        let serial = serial.into();
+    where
-
+        F: FnOnce(&mut CertificateBuilder<'_, yubikey_signer::Signer<'_, KT>>) -> der::Result<()>,
-        let mut tbs_cert = Buffer::new(Vec::with_capacity(CB_OBJ_MAX));
+    {
-
+        let signer = yubikey_signer::Signer::new(yubikey, key, subject_pki.owned_to_ref())?;
-        let signature_algorithm = match subject_pki.algorithm() {
+        let mut builder = CertificateBuilder::new(
-            AlgorithmId::Rsa1024 | AlgorithmId::Rsa2048 => SignatureId::Sha256WithRsaEncryption,
+            Profile::Manual { issuer: None },
-            AlgorithmId::EccP256 | AlgorithmId::EccP384 => SignatureId::EcdsaWithSha256,
-        };
-
-        cookie_factory::gen(
-            x509::write::tbs_certificate(
-                &serial.to_bytes(),
-                &signature_algorithm,
-                // Issuer and subject are the same in self-signed certificates.
-                subject,
-                Utc::now(),
-                not_after,
-                subject,
-                &subject_pki,
-                extensions,
-            ),
-            tbs_cert.deref_mut(),
-        )
-        .expect("can serialize to Vec");
-
-        let signature = match signature_algorithm {
-            SignatureId::Sha256WithRsaEncryption => {
-                use cookie_factory::{combinator::slice, sequence::tuple};
-                use x509::{
-                    der::write::{der_octet_string, der_sequence},
-                    write::algorithm_identifier,
-                };
-
-                let em_len = if let AlgorithmId::Rsa1024 = subject_pki.algorithm() {
-                    128
-                } else {
-                    256
-                };
-
-                let h = Sha256::digest(&tbs_cert);
-
-                let t = cookie_factory::gen_simple(
-                    der_sequence((
-                        algorithm_identifier(&DigestId::Sha256),
-                        der_octet_string(&h),
-                    )),
-                    vec![],
-                )
-                .expect("can serialize into Vec");
-
-                let em = cookie_factory::gen_simple(
-                    tuple((
-                        slice(&[0x00, 0x01]),
-                        slice(&vec![0xff; em_len - t.len() - 3]),
-                        slice(&[0x00]),
-                        slice(t),
-                    )),
-                    vec![],
-                )
-                .expect("can serialize to Vec");
-
-                sign_data(yubikey, &em, subject_pki.algorithm(), key)
-            }
-            SignatureId::EcdsaWithSha256 => sign_data(
-                yubikey,
-                &Sha256::digest(&tbs_cert),
-                subject_pki.algorithm(),
-                key,
-            ),
-        }?;
-
-        let mut data = Buffer::new(Vec::with_capacity(CB_OBJ_MAX));
-
-        cookie_factory::gen(
-            x509::write::certificate(&tbs_cert, &signature_algorithm, &signature),
-            data.deref_mut(),
-        )
-        .expect("can serialize to Vec");
-
-        let (issuer, subject) = parse_x509_certificate(&data)
-            .map(|(_, cert)| {
-                (
-                    cert.tbs_certificate.issuer.to_string(),
-                    cert.tbs_certificate.subject.to_string(),
-                )
-            })
-            .expect("We just serialized this correctly");
-
-        let cert = Certificate {
             serial,
-            issuer,
+            validity,
             subject,
             subject_pki,
-            data,
+            &signer,
-        };
+        )
+        .map_err(|_| Error::KeyError)?;
 
+        // Add custom extensions
+        extensions(&mut builder)?;
+
+        let cert = builder.build().map_err(|_| Error::KeyError)?;
+        let cert = Self { cert };
         cert.write(yubikey, key, CertInfo::Uncompressed)?;
 
         Ok(cert)
@@ -480,18 +141,18 @@ impl Certificate {
             return Err(Error::InvalidObject);
         }
 
-        Certificate::from_bytes(buf)
+        Self::from_bytes(buf)
     }
 
     /// Write this certificate into the YubiKey in the given slot
     pub fn write(&self, yubikey: &mut YubiKey, slot: SlotId, certinfo: CertInfo) -> Result<()> {
         let txn = yubikey.begin_transaction()?;
-        write_certificate(&txn, slot, Some(&self.data), certinfo)
+        let data = self.cert.to_der().map_err(|_| Error::InvalidObject)?;
+        write_certificate(&txn, slot, Some(&data), certinfo)
     }
 
     /// Delete a certificate located at the given slot of the given YubiKey
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn delete(yubikey: &mut YubiKey, slot: SlotId) -> Result<()> {
         let txn = yubikey.begin_transaction()?;
         write_certificate(&txn, slot, None, CertInfo::Uncompressed)
@@ -506,55 +167,27 @@ impl Certificate {
             return Err(Error::SizeError);
         }
 
-        let parsed_cert = match parse_x509_certificate(&cert) {
+        x509_cert::Certificate::from_der(&cert)
-            Ok((_, cert)) => cert,
+            .map(|cert| Self { cert })
-            _ => return Err(Error::InvalidObject),
+            .map_err(|_| Error::InvalidObject)
-        };
-
-        let serial = Serial::try_from(parsed_cert.tbs_certificate.serial.to_bytes_be().as_slice())
-            .map_err(|_| Error::InvalidObject)?;
-        let issuer = parsed_cert.tbs_certificate.issuer.to_string();
-        let subject = parsed_cert.tbs_certificate.subject.to_string();
-        let subject_pki = PublicKeyInfo::parse(&parsed_cert.tbs_certificate.subject_pki)?;
-
-        Ok(Certificate {
-            serial,
-            issuer,
-            subject,
-            subject_pki,
-            data: cert,
-        })
-    }
-
-    /// Returns the serial number of the certificate.
-    pub fn serial(&self) -> &Serial {
-        &self.serial
     }
 
     /// Returns the Issuer field of the certificate.
-    pub fn issuer(&self) -> &str {
+    pub fn issuer(&self) -> String {
-        &self.issuer
+        self.cert.tbs_certificate.issuer.to_string()
     }
 
     /// Returns the SubjectName field of the certificate.
-    pub fn subject(&self) -> &str {
+    pub fn subject(&self) -> String {
-        &self.subject
+        self.cert.tbs_certificate.subject.to_string()
     }
 
     /// Returns the SubjectPublicKeyInfo field of the certificate.
-    pub fn subject_pki(&self) -> &PublicKeyInfo {
+    pub fn subject_pki(&self) -> SubjectPublicKeyInfoRef<'_> {
-        &self.subject_pki
+        self.cert
-    }
+            .tbs_certificate
-
+            .subject_public_key_info
-    /// Extract the inner buffer
+            .owned_to_ref()
-    pub fn into_buffer(self) -> Buffer {
-        self.data
-    }
-}
-
-impl AsRef<[u8]> for Certificate {
-    fn as_ref(&self) -> &[u8] {
-        self.data.as_ref()
     }
 }
 
@@ -590,113 +223,237 @@ pub(crate) fn write_certificate(
 ) -> Result<()> {
     let object_id = slot.object_id();
 
-    if data.is_none() {
+    if let Some(data) = data {
-        return txn.save_object(object_id, &[]);
+        let mut buf = [0u8; CB_OBJ_MAX];
+        let mut offset = Tlv::write(&mut buf, TAG_CERT, data)?;
+
+        // write compression info and LRC trailer
+        offset += Tlv::write(&mut buf[offset..], TAG_CERT_COMPRESS, &[certinfo.into()])?;
+        offset += Tlv::write(&mut buf[offset..], TAG_CERT_LRC, &[])?;
+
+        txn.save_object(object_id, &buf[..offset])
+    } else {
+        txn.save_object(object_id, &[])
     }
-
-    let data = data.unwrap();
-
-    let mut buf = [0u8; CB_OBJ_MAX];
-    let mut offset = Tlv::write(&mut buf, TAG_CERT, data)?;
-
-    // write compression info and LRC trailer
-    offset += Tlv::write(&mut buf[offset..], TAG_CERT_COMPRESS, &[certinfo.into()])?;
-    offset += Tlv::write(&mut buf[offset..], TAG_CERT_LRC, &[])?;
-
-    txn.save_object(object_id, &buf[..offset])
 }
 
-mod read_pki {
+pub mod yubikey_signer {
-    use der_parser::{
+    //! Signer implementation for yubikey
-        asn1_rs::Any,
+
-        ber::BerObjectContent,
+    use crate::{
-        der::{parse_der_integer, parse_der_sequence_defined_g, DerObject},
+        error::{Error, Result},
-        error::BerError,
+        piv::AlgorithmId,
+        piv::{sign_data, SlotId},
+        YubiKey,
+    };
+    use der::{
+        asn1::{Any, OctetString},
+        oid::db::rfc5912,
+        Encode, Sequence,
+    };
+    use sha2::{Digest, Sha256, Sha384};
+    use signature::Keypair;
+    use std::{cell::RefCell, fmt, io::Write, marker::PhantomData};
+    use x509_cert::spki::{
+        self, AlgorithmIdentifierOwned, DynSignatureAlgorithmIdentifier, EncodePublicKey,
+        SignatureBitStringEncoding, SubjectPublicKeyInfoRef,
     };
-    use nom::{combinator, sequence::pair, IResult};
-    use rsa::{BigUint, RsaPublicKey};
 
-    use super::{OID_NIST_P256, OID_NIST_P384};
+    type SigResult<T> = core::result::Result<T, signature::Error>;
-    use crate::{piv::AlgorithmId, Error, Result};
 
-    /// From [RFC 8017](https://tools.ietf.org/html/rfc8017#appendix-A.1.1):
+    /// Key to be used to sign certificates
-    /// ```text
+    pub trait KeyType {
-    /// RSAPublicKey ::= SEQUENCE {
+        /// Error returned when working with signature
-    ///     modulus           INTEGER,  -- n
+        type Error: Into<signature::Error> + fmt::Debug;
-    ///     publicExponent    INTEGER   -- e
+        /// The signature type returned by the signer
-    /// }
+        type Signature: SignatureBitStringEncoding
-    /// ```
+            + for<'s> TryFrom<&'s [u8], Error = Self::Error>
-    pub(super) fn rsa_pubkey(encoded: &[u8]) -> Result<RsaPublicKey> {
+            + fmt::Debug;
-        fn parse_rsa_pubkey(i: &[u8]) -> IResult<&[u8], (DerObject<'_>, DerObject<'_>), BerError> {
+        /// The public key used to verify signature
-            parse_der_sequence_defined_g(|i, _| pair(parse_der_integer, parse_der_integer)(i))(i)
+        type VerifyingKey: EncodePublicKey
-        }
+            + DynSignatureAlgorithmIdentifier
+            + Clone
+            + From<Self::PublicKey>;
+        /// Public key type used to load the SPKI formatted key
+        type PublicKey: for<'a> TryFrom<SubjectPublicKeyInfoRef<'a>, Error = spki::Error>;
 
-        fn rsa_pubkey_parts(i: &[u8]) -> IResult<&[u8], (BigUint, BigUint), BerError> {
+        /// The algorithm used when talking with the yubikey
-            combinator::map(parse_rsa_pubkey, |(modulus, public_exponent)| {
+        const ALGORITHM: AlgorithmId;
-                let n = match modulus.content {
-                    BerObjectContent::Integer(s) => BigUint::from_bytes_be(s),
-                    _ => panic!("expected DER integer"),
-                };
-                let e = match public_exponent.content {
-                    BerObjectContent::Integer(s) => BigUint::from_bytes_be(s),
-                    _ => panic!("expected DER integer"),
-                };
 
-                (n, e)
+        /// Prepare buffer before submitting it for signature
-            })(i)
+        fn prepare(input: &[u8]) -> SigResult<Vec<u8>>;
-        }
+        /// Read back the signature from the device
-
+        fn read_signature(input: &[u8]) -> SigResult<Self::Signature>;
-        let (n, e) = match rsa_pubkey_parts(encoded) {
-            Ok((_, res)) => res,
-            _ => return Err(Error::InvalidObject),
-        };
-
-        RsaPublicKey::new(n, e).map_err(|_| Error::InvalidObject)
     }
 
-    /// From [RFC 5480](https://tools.ietf.org/html/rfc5480#section-2.1.1):
+    impl KeyType for p256::NistP256 {
-    /// ```text
+        const ALGORITHM: AlgorithmId = AlgorithmId::EccP256;
-    /// ECParameters ::= CHOICE {
+        type Error = ecdsa::Error;
-    ///   namedCurve         OBJECT IDENTIFIER
+        type Signature = p256::ecdsa::DerSignature;
-    ///   -- implicitCurve   NULL
+        type VerifyingKey = p256::ecdsa::VerifyingKey;
-    ///   -- specifiedCurve  SpecifiedECDomain
+        type PublicKey = p256::ecdsa::VerifyingKey;
-    /// }
-    /// ```
-    pub(super) fn ec_parameters(parameters: &Any<'_>) -> Result<AlgorithmId> {
-        let curve_oid = parameters.as_oid().map_err(|_| Error::InvalidObject)?;
 
-        match curve_oid.to_string().as_str() {
+        fn prepare(input: &[u8]) -> SigResult<Vec<u8>> {
-            OID_NIST_P256 => Ok(AlgorithmId::EccP256),
+            Ok(Sha256::digest(input).to_vec())
-            OID_NIST_P384 => Ok(AlgorithmId::EccP384),
+        }
-            _ => Err(Error::AlgorithmError),
+
+        fn read_signature(input: &[u8]) -> SigResult<Self::Signature> {
+            Self::Signature::from_bytes(input)
+        }
+    }
+
+    impl KeyType for p384::NistP384 {
+        const ALGORITHM: AlgorithmId = AlgorithmId::EccP384;
+        type Error = ecdsa::Error;
+        type Signature = p384::ecdsa::DerSignature;
+        type VerifyingKey = p384::ecdsa::VerifyingKey;
+        type PublicKey = p384::ecdsa::VerifyingKey;
+
+        fn prepare(input: &[u8]) -> SigResult<Vec<u8>> {
+            Ok(Sha384::digest(input).to_vec())
+        }
+
+        fn read_signature(input: &[u8]) -> SigResult<Self::Signature> {
+            Self::Signature::from_bytes(input)
+        }
+    }
+
+    /// Trait used to handle subtypes of RSA keys
+    pub trait RsaLength {
+        /// The length of the RSA key in bits
+        const BIT_LENGTH: usize;
+        /// The algorithm to use when talking with the Yubikey.
+        const ALGORITHM: AlgorithmId;
+    }
+
+    /// RSA 1024 bits key
+    pub struct Rsa1024;
+
+    impl RsaLength for Rsa1024 {
+        const BIT_LENGTH: usize = 1024;
+        const ALGORITHM: AlgorithmId = AlgorithmId::Rsa1024;
+    }
+
+    /// RSA 2048 bits key
+    pub struct Rsa2048;
+
+    impl RsaLength for Rsa2048 {
+        const BIT_LENGTH: usize = 2048;
+        const ALGORITHM: AlgorithmId = AlgorithmId::Rsa2048;
+    }
+
+    /// RSA keys used to sign certificates
+    pub struct YubiRsa<N: RsaLength> {
+        _len: PhantomData<N>,
+    }
+
+    impl<N: RsaLength> KeyType for YubiRsa<N> {
+        type Error = signature::Error;
+        type Signature = rsa::pkcs1v15::Signature;
+        type VerifyingKey = rsa::pkcs1v15::VerifyingKey<Sha256>;
+        type PublicKey = rsa::RsaPublicKey;
+        const ALGORITHM: AlgorithmId = N::ALGORITHM;
+
+        fn prepare(input: &[u8]) -> SigResult<Vec<u8>> {
+            let hashed = Sha256::digest(input).to_vec();
+
+            OctetString::new(hashed)
+                .map_err(|e| e.into())
+                .and_then(Self::emsa_pkcs1_1_5)
+                .map_err(signature::Error::from_source)
+        }
+
+        fn read_signature(input: &[u8]) -> SigResult<Self::Signature> {
+            Self::Signature::try_from(input)
+        }
+    }
+
+    impl<N: RsaLength> YubiRsa<N> {
+        /// https://www.rfc-editor.org/rfc/rfc8017#section-9.2
+        fn emsa_pkcs1_1_5(digest: OctetString) -> Result<Vec<u8>> {
+            /// https://www.rfc-editor.org/rfc/rfc8017#appendix-A.2.4
+            #[derive(Debug, Sequence)]
+            struct DigestInfo {
+                digest_algorithm: AlgorithmIdentifierOwned,
+                digest: OctetString,
+            }
+
+            let em_len = N::BIT_LENGTH / 8;
+
+            let null = Any::null();
+
+            let t = DigestInfo {
+                digest_algorithm: AlgorithmIdentifierOwned {
+                    oid: rfc5912::ID_SHA_256,
+                    parameters: Some(null),
+                },
+                digest,
+            };
+            let t = t.to_der()?;
+
+            let ps = vec![0xff; em_len - t.len() - 3];
+            assert!(ps.len() >= 8, "spec violation");
+
+            let mut out = Vec::with_capacity(em_len);
+            out.write(&[0x00, 0x01]).map_err(|_| Error::MemoryError)?;
+            out.write(&ps).map_err(|_| Error::MemoryError)?;
+            out.write(&[0x00]).map_err(|_| Error::MemoryError)?;
+            out.write(&t).map_err(|_| Error::MemoryError)?;
+            Ok(out)
+        }
+    }
+
+    /// The entrypoint to sign data with the yubikey.
+    pub struct Signer<'y, KT: KeyType> {
+        yubikey: RefCell<&'y mut YubiKey>,
+        key: SlotId,
+        public_key: KT::VerifyingKey,
+    }
+
+    impl<'y, KT: KeyType> Signer<'y, KT> {
+        /// Create new Signer
+        pub fn new(
+            yubikey: &'y mut YubiKey,
+            key: SlotId,
+            subject_pki: SubjectPublicKeyInfoRef<'_>,
+        ) -> Result<Self> {
+            let public_key = KT::PublicKey::try_from(subject_pki).map_err(|_| Error::ParseError)?;
+            let public_key = public_key.into();
+
+            Ok(Self {
+                yubikey: RefCell::new(yubikey),
+                key,
+                public_key,
+            })
+        }
+    }
+
+    impl<'y, KT: KeyType> Keypair for Signer<'y, KT> {
+        type VerifyingKey = KT::VerifyingKey;
+        fn verifying_key(&self) -> <Self as Keypair>::VerifyingKey {
+            self.public_key.clone()
+        }
+    }
+
+    impl<'y, KT: KeyType> DynSignatureAlgorithmIdentifier for Signer<'y, KT> {
+        fn signature_algorithm_identifier(&self) -> spki::Result<AlgorithmIdentifierOwned> {
+            self.verifying_key().signature_algorithm_identifier()
+        }
+    }
+
+    impl<'y, KT: KeyType> signature::Signer<KT::Signature> for Signer<'y, KT> {
+        fn try_sign(&self, msg: &[u8]) -> SigResult<KT::Signature> {
+            let data = KT::prepare(msg)?;
+
+            let out = sign_data(
+                &mut self.yubikey.borrow_mut(),
+                &data,
+                KT::ALGORITHM,
+                self.key,
+            )
+            .map_err(signature::Error::from_source)?;
+            let out = KT::read_signature(&out)?;
+            Ok(out)
         }
     }
 }
-
-mod write_pki {
-    use cookie_factory::{SerializeFn, WriteContext};
-    use rsa::{BigUint, PublicKeyParts, RsaPublicKey};
-    use std::io::Write;
-    use x509::der::write::{der_integer, der_sequence};
-
-    /// Encodes a usize as an ASN.1 integer using DER.
-    fn der_integer_biguint<'a, W: Write + 'a>(num: &'a BigUint) -> impl SerializeFn<W> + 'a {
-        move |w: WriteContext<W>| der_integer(&num.to_bytes_be())(w)
-    }
-
-    /// From [RFC 8017](https://tools.ietf.org/html/rfc8017#appendix-A.1.1):
-    /// ```text
-    /// RSAPublicKey ::= SEQUENCE {
-    ///     modulus           INTEGER,  -- n
-    ///     publicExponent    INTEGER   -- e
-    /// }
-    /// ```
-    pub(super) fn rsa_pubkey<'a, W: Write + 'a>(
-        pubkey: &'a RsaPublicKey,
-    ) -> impl SerializeFn<W> + 'a {
-        der_sequence((
-            der_integer_biguint(pubkey.n()),
-            der_integer_biguint(pubkey.e()),
-        ))
-    }
-}

src/chuid.rs

@@ -30,7 +30,7 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-use crate::{Error, Result, YubiKey};
+use crate::{Result, YubiKey};
 use std::fmt::{self, Debug, Display};
 use uuid::Uuid;
 
@@ -61,6 +61,7 @@ const OBJ_CHUID: u32 = 0x005f_c102;
 /// - 0x35: Exp. Date (hard-coded)
 /// - 0x3e: Signature (hard-coded, empty)
 /// - 0xfe: Error Detection Code (hard-coded)
+#[allow(dead_code)]
 const CHUID_TMPL: &[u8] = &[
     0x30, 0x19, 0xd4, 0xe7, 0x39, 0xda, 0x73, 0x9c, 0xed, 0x39, 0xce, 0x73, 0x9d, 0x83, 0x68, 0x58,
     0x21, 0x08, 0x42, 0x10, 0x84, 0x21, 0xc8, 0x42, 0x10, 0xc3, 0xeb, 0x34, 0x10, 0x00, 0x00, 0x00,
@@ -86,12 +87,13 @@ impl ChuId {
     pub fn fascn(&self) -> [u8; Self::FASCN_SIZE] {
         self.0[CHUID_FASCN_OFFS..(CHUID_FASCN_OFFS + Self::FASCN_SIZE)]
             .try_into()
-            .unwrap()
+            .expect("should be FASCN_SIZE")
     }
 
     /// Return Card UUID/GUID component of CHUID
     pub fn uuid(&self) -> Uuid {
-        Uuid::from_slice(&self.0[CHUID_GUID_OFFS..(CHUID_GUID_OFFS + 16)]).unwrap()
+        Uuid::from_slice(&self.0[CHUID_GUID_OFFS..(CHUID_GUID_OFFS + 16)])
+            .expect("should be UUID-sized")
     }
 
     /// Return expiration date component of CHUID
@@ -99,24 +101,18 @@ impl ChuId {
     pub fn expiration(&self) -> [u8; Self::EXPIRATION_SIZE] {
         self.0[CHUID_EXPIRATION_OFFS..(CHUID_EXPIRATION_OFFS + Self::EXPIRATION_SIZE)]
             .try_into()
-            .unwrap()
+            .expect("should be EXPIRATION_SIZE")
     }
 
     /// Get Cardholder Unique Identifier (CHUID)
     pub fn get(yubikey: &mut YubiKey) -> Result<ChuId> {
         let txn = yubikey.begin_transaction()?;
         let response = txn.fetch_object(OBJ_CHUID)?;
-
+        Ok(response[..Self::BYTE_SIZE].try_into().map(Self)?)
-        if response.len() != CHUID_TMPL.len() {
-            return Err(Error::GenericError);
-        }
-
-        Ok(ChuId(response[..Self::BYTE_SIZE].try_into().unwrap()))
     }
 
     /// Set Cardholder Unique Identifier (CHUID)
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn set(&self, yubikey: &mut YubiKey) -> Result<()> {
         let mut buf = CHUID_TMPL.to_vec();
         buf[..Self::BYTE_SIZE].copy_from_slice(&self.0);

src/config.rs

@@ -111,7 +111,7 @@ impl Config {
                     error!("pin timestamp in admin metadata is an invalid size");
                 } else {
                     // TODO(tarcieri): double-check endianness is correct
-                    let pin_last_changed = u32::from_le_bytes(item.try_into().unwrap());
+                    let pin_last_changed = u32::from_le_bytes([item[0], item[1], item[2], item[3]]);
 
                     if pin_last_changed != 0 {
                         config.pin_last_changed =

src/error.rs

@@ -164,6 +164,18 @@ impl Display for Error {
     }
 }
 
+impl From<std::array::TryFromSliceError> for Error {
+    fn from(_: std::array::TryFromSliceError) -> Error {
+        Error::SizeError
+    }
+}
+
+impl From<std::time::SystemTimeError> for Error {
+    fn from(_: std::time::SystemTimeError) -> Error {
+        Error::GenericError
+    }
+}
+
 impl From<pcsc::Error> for Error {
     fn from(err: pcsc::Error) -> Error {
         Error::PcscError { inner: Some(err) }
@@ -179,3 +191,9 @@ impl std::error::Error for Error {
         }
     }
 }
+
+impl From<x509_cert::der::Error> for Error {
+    fn from(_err: x509_cert::der::Error) -> Error {
+        Error::ParseError
+    }
+}

src/lib.rs

@@ -2,9 +2,16 @@
 #![doc(
     html_logo_url = "https://raw.githubusercontent.com/iqlusioninc/yubikey.rs/main/img/logo-sq.png"
 )]
-#![cfg_attr(docsrs, feature(doc_cfg))]
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
 #![forbid(unsafe_code)]
-#![warn(missing_docs, rust_2018_idioms, trivial_casts, unused_qualifications)]
+#![warn(
+    clippy::mod_module_files,
+    clippy::unwrap_used,
+    missing_docs,
+    rust_2018_idioms,
+    unused_lifetimes,
+    unused_qualifications
+)]
 
 // Adapted from yubico-piv-tool:
 // <https://github.com/Yubico/yubico-piv-tool/>

src/metadata.rs

@@ -71,7 +71,7 @@ impl<T: MetadataType> Default for Metadata<T> {
     fn default() -> Self {
         Metadata {
             inner: Zeroizing::new(vec![]),
-            _marker: PhantomData::default(),
+            _marker: PhantomData,
         }
     }
 }
@@ -82,13 +82,12 @@ impl<T: MetadataType> Metadata<T> {
         let data = txn.fetch_object(T::obj_id())?;
         Ok(Metadata {
             inner: Tlv::parse_single(data, T::tag())?,
-            _marker: PhantomData::default(),
+            _marker: PhantomData,
         })
     }
 
     /// Write metadata
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub(crate) fn write(&self, txn: &Transaction<'_>) -> Result<()> {
         if self.inner.len() > CB_OBJ_MAX - CB_OBJ_TAG_MAX {
             return Err(Error::GenericError);
@@ -106,7 +105,6 @@ impl<T: MetadataType> Metadata<T> {
 
     /// Delete metadata
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub(crate) fn delete(txn: &Transaction<'_>) -> Result<()> {
         txn.save_object(T::obj_id(), &[])
     }
@@ -130,7 +128,6 @@ impl<T: MetadataType> Metadata<T> {
 
     /// Set metadata item
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub(crate) fn set_item(&mut self, tag: u8, item: &[u8]) -> Result<()> {
         let mut cb_temp: usize = 0;
         let mut tag_temp: u8 = 0;

src/mgm.rs

@@ -128,7 +128,6 @@ impl MgmKey {
 
     /// Get derived management key (MGM)
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn get_derived(yubikey: &mut YubiKey, pin: &[u8]) -> Result<Self> {
         let txn = yubikey.begin_transaction()?;
 
@@ -153,7 +152,6 @@ impl MgmKey {
 
     /// Get protected management key (MGM)
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn get_protected(yubikey: &mut YubiKey) -> Result<Self> {
         let txn = yubikey.begin_transaction()?;
 
@@ -184,7 +182,6 @@ impl MgmKey {
     ///
     /// This will wipe any metadata related to derived and PIN-protected management keys.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn set_default(yubikey: &mut YubiKey) -> Result<()> {
         MgmKey::default().set_manual(yubikey, false)
     }
@@ -196,7 +193,6 @@ impl MgmKey {
     ///
     /// This will wipe any metadata related to derived and PIN-protected management keys.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn set_manual(&self, yubikey: &mut YubiKey, require_touch: bool) -> Result<()> {
         let txn = yubikey.begin_transaction()?;
 
@@ -256,7 +252,6 @@ impl MgmKey {
     ///
     /// This enables key management operations to be performed with access to the PIN.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn set_protected(&self, yubikey: &mut YubiKey) -> Result<()> {
         let txn = yubikey.begin_transaction()?;
 

src/mscmap.rs

@@ -41,7 +41,6 @@ const TAG_MSCMAP: u8 = 0x81;
 ///
 /// Defined in Microsoft's Smart Card Minidriver Specification:
 /// <https://docs.microsoft.com/en-us/previous-versions/windows/hardware/design/dn631754(v=vs.85)>
-#[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
 #[derive(Clone, Debug)]
 pub struct MsContainer {
     /// Container name.
@@ -141,7 +140,7 @@ impl MsContainer {
         let name_bytes_len = Self::NAME_LEN * 2;
 
         for (i, chunk) in bytes[..name_bytes_len].chunks_exact(2).enumerate() {
-            name[i] = u16::from_le_bytes(chunk.try_into().unwrap());
+            name[i] = u16::from_le_bytes([chunk[0], chunk[1]]);
         }
 
         let mut cert_fingerprint = [0u8; 20];
@@ -151,11 +150,10 @@ impl MsContainer {
             name,
             slot: bytes[name_bytes_len].try_into()?,
             key_spec: bytes[name_bytes_len + 1],
-            key_size_bits: u16::from_le_bytes(
+            key_size_bits: u16::from_le_bytes([
-                bytes[(name_bytes_len + 2)..(name_bytes_len + 4)]
+                bytes[name_bytes_len + 2],
-                    .try_into()
+                bytes[name_bytes_len + 3],
-                    .unwrap(),
+            ]),
-            ),
             flags: bytes[name_bytes_len + 4],
             pin_id: bytes[name_bytes_len + 5],
             associated_echd_container: bytes[name_bytes_len + 6],
@@ -184,7 +182,10 @@ impl MsContainer {
         bytes.push(self.pin_id);
         bytes.push(self.associated_echd_container);
         bytes.extend_from_slice(&self.cert_fingerprint);
-        bytes.as_slice().try_into().unwrap()
+        bytes
+            .as_slice()
+            .try_into()
+            .expect("should be REC_LEN-sized")
     }
 }
 

src/msroots.rs

@@ -57,7 +57,6 @@ const TAG_MSROOTS_MID: u8 = 0x83;
 ///
 /// For more information, see:
 /// <https://docs.microsoft.com/en-us/windows-hardware/drivers/smartcard/developer-guidelines#-interoperability-with-msroots>
-#[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
 pub struct MsRoots(Vec<u8>);
 
 impl MsRoots {

src/piv.rs

@@ -44,7 +44,7 @@
 
 use crate::{
     apdu::{Ins, StatusWords},
-    certificate::{self, Certificate, PublicKeyInfo},
+    certificate::{self, Certificate},
     consts::CB_OBJ_MAX,
     error::{Error, Result},
     policy::{PinPolicy, TouchPolicy},
@@ -53,15 +53,16 @@ use crate::{
     yubikey::YubiKey,
     Buffer, ObjectId,
 };
-use elliptic_curve::sec1::EncodedPoint as EcPublicKey;
+use elliptic_curve::{sec1::EncodedPoint as EcPublicKey, PublicKey};
 use log::{debug, error, warn};
 use p256::NistP256;
 use p384::NistP384;
-use rsa::{BigUint, RsaPublicKey};
+use rsa::{pkcs8::EncodePublicKey, BigUint, RsaPublicKey};
 use std::{
     fmt::{Display, Formatter},
     str::FromStr,
 };
+use x509_cert::{der::Decode, spki::SubjectPublicKeyInfoOwned};
 
 #[cfg(feature = "untested")]
 use {
@@ -441,10 +442,11 @@ impl ManagementSlotId {
 }
 
 /// Personal Identity Verification (PIV) key slots
-pub const SLOTS: [SlotId; 27] = [
+pub const SLOTS: [SlotId; 28] = [
     SlotId::Authentication,
     SlotId::Signature,
     SlotId::KeyManagement,
+    SlotId::Attestation,
     SlotId::Retired(RetiredSlotId::R1),
     SlotId::Retired(RetiredSlotId::R2),
     SlotId::Retired(RetiredSlotId::R3),
@@ -519,7 +521,6 @@ impl AlgorithmId {
     }
 
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     fn get_elem_len(self) -> usize {
         match self {
             AlgorithmId::Rsa1024 => 64,
@@ -530,7 +531,6 @@ impl AlgorithmId {
     }
 
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     fn get_param_tag(self) -> u8 {
         match self {
             AlgorithmId::Rsa1024 | AlgorithmId::Rsa2048 => 0x01,
@@ -591,7 +591,7 @@ pub fn generate(
     algorithm: AlgorithmId,
     pin_policy: PinPolicy,
     touch_policy: TouchPolicy,
-) -> Result<PublicKeyInfo> {
+) -> Result<SubjectPublicKeyInfoOwned> {
     // Keygen messages
     // TODO(tarcieri): extract these into an I18N-handling type?
     const SZ_SETTING_ROCA: &str = "Enable_Unsafe_Keygen_ROCA";
@@ -701,7 +701,6 @@ pub fn generate(
 }
 
 #[cfg(feature = "untested")]
-#[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
 fn write_key(
     yubikey: &mut YubiKey,
     slot: SlotId,
@@ -750,7 +749,6 @@ fn write_key(
 
 /// The key data that makes up an RSA key.
 #[cfg(feature = "untested")]
-#[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
 pub struct RsaKeyData {
     /// The secret prime `p`.
     p: Buffer,
@@ -766,10 +764,12 @@ pub struct RsaKeyData {
 
 #[cfg(feature = "untested")]
 impl RsaKeyData {
-    /// Generates a new RSA key data set from two randomly generated, secret, primes.
+    /// Generates a new RSA key data set from two (randomly generated) secret primes.
     ///
-    /// Panics if `secret_p` or `secret_q` are invalid primes.
+    /// # Returns
-    pub fn new(secret_p: &[u8], secret_q: &[u8]) -> Self {
+    /// - `Ok(key_data)` if `secret_p` and `secret_q` are valid primes.
+    /// - `Err(Error::AlgorithmError)` if `secret_p`/`secret_q` are invalid primes.
+    pub fn new(secret_p: &[u8], secret_q: &[u8]) -> Result<Self> {
         let p = BigUint::from_bytes_be(secret_p);
         let q = BigUint::from_bytes_be(secret_q);
 
@@ -780,10 +780,10 @@ impl RsaKeyData {
             p_t.lcm(&q_t)
         };
 
-        let exp = BigUint::from_u64(KEYDATA_RSA_EXP).unwrap();
+        let exp = BigUint::from_u64(KEYDATA_RSA_EXP).ok_or(Error::AlgorithmError)?;
 
-        let d = exp.mod_inverse(&totient).unwrap();
+        let d = exp.mod_inverse(&totient).ok_or(Error::AlgorithmError)?;
-        let d = d.to_biguint().unwrap();
+        let d = d.to_biguint().ok_or(Error::AlgorithmError)?;
 
         // We calculate the optimization values ahead of time, instead of making the user
         // do so.
@@ -791,16 +791,16 @@ impl RsaKeyData {
         let dp = &d % (&p - BigUint::one());
         let dq = &d % (&q - BigUint::one());
 
-        let qinv = q.clone().mod_inverse(&p).unwrap();
+        let qinv = q.clone().mod_inverse(&p).ok_or(Error::AlgorithmError)?;
         let (_, qinv) = qinv.to_bytes_be();
 
-        RsaKeyData {
+        Ok(RsaKeyData {
             p: Zeroizing::new(p.to_bytes_be()),
             q: Zeroizing::new(q.to_bytes_be()),
             dp: Zeroizing::new(dp.to_bytes_be()),
             dq: Zeroizing::new(dq.to_bytes_be()),
             qinv: Zeroizing::new(qinv),
-        }
+        })
     }
 
     fn total_len(&self) -> usize {
@@ -812,7 +812,6 @@ impl RsaKeyData {
 ///
 /// Errors if `algorithm` isn't `AlgorithmId::Rsa1024` or `AlgorithmId::Rsa2048`.
 #[cfg(feature = "untested")]
-#[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
 pub fn import_rsa_key(
     yubikey: &mut YubiKey,
     slot: SlotId,
@@ -847,7 +846,6 @@ pub fn import_rsa_key(
 ///
 /// Errors if `algorithm` isn't `AlgorithmId::EccP256` or ` AlgorithmId::EccP384`.
 #[cfg(feature = "untested")]
-#[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
 pub fn import_ecc_key(
     yubikey: &mut YubiKey,
     slot: SlotId,
@@ -876,7 +874,6 @@ pub fn import_ecc_key(
 ///
 /// <https://developers.yubico.com/PIV/Introduction/PIV_attestation.html>
 #[cfg(feature = "untested")]
-#[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
 pub fn attest(yubikey: &mut YubiKey, key: SlotId) -> Result<Buffer> {
     let templ = [0, Ins::Attest.code(), key.into(), 0];
     let txn = yubikey.begin_transaction()?;
@@ -912,7 +909,6 @@ pub fn sign_data(
 
 /// Decrypt data using a PIV key.
 #[cfg(feature = "untested")]
-#[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
 pub fn decrypt_data(
     yubikey: &mut YubiKey,
     input: &[u8],
@@ -955,7 +951,7 @@ pub struct SlotMetadata {
     /// Imported or generated key
     pub origin: Option<Origin>,
     /// Pub key of the key
-    pub public: Option<PublicKeyInfo>,
+    pub public: Option<SubjectPublicKeyInfoOwned>,
     /// Whether PIN PUK and management key are default
     pub default: Option<bool>,
     /// Number of retries left
@@ -1110,7 +1106,7 @@ fn read_public_key(
     algorithm: AlgorithmId,
     input: &[u8],
     skip_asn1_tag: bool,
-) -> Result<PublicKeyInfo> {
+) -> Result<SubjectPublicKeyInfoOwned> {
     // TODO(str4d): Response is wrapped in an ASN.1 TLV:
     //
     //    0x7f 0x49 -> Application | Constructed | 0x49
@@ -1159,14 +1155,17 @@ fn read_public_key(
             }
             let exp = exp_tlv.value.to_vec();
 
-            Ok(PublicKeyInfo::Rsa {
+            let pubkey = RsaPublicKey::new(
-                algorithm,
+                BigUint::from_bytes_be(&modulus),
-                pubkey: RsaPublicKey::new(
+                BigUint::from_bytes_be(&exp),
-                    BigUint::from_bytes_be(&modulus),
+            )
-                    BigUint::from_bytes_be(&exp),
+            .map_err(|_| Error::InvalidObject)?;
-                )
+            Ok(SubjectPublicKeyInfoOwned::from_der(
-                .map_err(|_| Error::InvalidObject)?,
+                pubkey
-            })
+                    .to_public_key_der()
+                    .map_err(|_| Error::ParseError)?
+                    .as_bytes(),
+            )?)
         }
         AlgorithmId::EccP256 | AlgorithmId::EccP384 => {
             // 2-byte ASN.1 tag, 1-byte length (because all supported EC pubkey lengths
@@ -1194,16 +1193,22 @@ fn read_public_key(
 
             let point = tlv.value.to_vec();
 
-            match algorithm {
+            let pubkey = match algorithm {
-                AlgorithmId::EccP256 => {
+                AlgorithmId::EccP256 => PublicKey::<NistP256>::try_from(
-                    EcPublicKey::<NistP256>::from_bytes(point).map(PublicKeyInfo::EcP256)
+                    EcPublicKey::<NistP256>::from_bytes(point).map_err(|_| Error::InvalidObject)?,
-                }
+                )
-                AlgorithmId::EccP384 => {
+                .map_err(|_| Error::InvalidObject)?
-                    EcPublicKey::<NistP384>::from_bytes(point).map(PublicKeyInfo::EcP384)
+                .to_public_key_der(),
-                }
+                AlgorithmId::EccP384 => PublicKey::<NistP384>::try_from(
+                    EcPublicKey::<NistP384>::from_bytes(point).map_err(|_| Error::InvalidObject)?,
+                )
+                .map_err(|_| Error::InvalidObject)?
+                .to_public_key_der(),
                 _ => return Err(Error::AlgorithmError),
             }
-            .map_err(|_| Error::InvalidObject)
+            .map_err(|_| Error::InvalidObject)?;
+
+            Ok(SubjectPublicKeyInfoOwned::from_der(pubkey.as_bytes())?)
         }
     }
 }

src/reader.rs

@@ -1,6 +1,6 @@
 //! Support for enumerating available PC/SC card readers.
 
-use crate::{Result, YubiKey};
+use crate::{Error, Result, YubiKey};
 use std::{
     borrow::Cow,
     ffi::CStr,
@@ -43,7 +43,8 @@ impl Context {
         let Self { ctx, reader_names } = self;
 
         let reader_cstrs: Vec<_> = {
-            let c = ctx.lock().unwrap();
+            // TODO(tarcieri): better error?
+            let c = ctx.lock().map_err(|_| Error::GenericError)?;
 
             // ensure PC/SC context is valid
             c.is_valid()?;
@@ -90,7 +91,8 @@ impl<'ctx> Reader<'ctx> {
 
     /// Connect to this reader, returning its `pcsc::Card`.
     pub(crate) fn connect(&self) -> Result<pcsc::Card> {
-        let ctx = self.ctx.lock().unwrap();
+        // TODO(tarcieri): better error?
+        let ctx = self.ctx.lock().map_err(|_| Error::GenericError)?;
         Ok(ctx.connect(self.name, pcsc::ShareMode::Shared, pcsc::Protocols::T1)?)
     }
 }

src/transaction.rs

@@ -96,11 +96,7 @@ impl<'tx> Transaction<'tx> {
             return Err(Error::GenericError);
         }
 
-        if response.data().len() < 3 {
+        Ok(response.data()[..3].try_into().map(Version::new)?)
-            return Err(Error::SizeError);
-        }
-
-        Ok(Version::new(response.data()[..3].try_into().unwrap()))
     }
 
     /// Get YubiKey device serial number.

src/yubikey.rs

@@ -178,27 +178,44 @@ impl fmt::Debug for YubiKey {
 impl YubiKey {
     /// Open a connection to a YubiKey.
     ///
-    /// Returns an error if there is more than one YubiKey detected.
+    /// Returns an error if more than one YubiKey is detected (or none at all).
+    ///
+    /// NOTE: If multiple YubiKeys are connected, but we are only able to
+    /// open one of them (e.g. because the other one is in use, and the
+    /// connection doesn't allow sharing), the YubiKey that we were able to
+    /// open is returned.
     ///
     /// If you need to operate in environments with more than one YubiKey
     /// attached to the same system, use [`YubiKey::open_by_serial`] or
     /// [`yubikey::reader::Context`][`Context`] to select from the available
     /// PC/SC readers.
     pub fn open() -> Result<Self> {
+        let mut yubikey: Option<Self> = None;
+
         let mut readers = Context::open()?;
-        let mut reader_iter = readers.iter()?;
+        for reader in readers.iter()? {
+            if let Ok(yk_found) = reader.open() {
+                if let Some(yk_stored) = yubikey {
+                    // We found two YubiKeys, so we won't use either.
+                    // Don't reset them.
+                    let _ = yk_stored.disconnect(pcsc::Disposition::LeaveCard);
+                    let _ = yk_found.disconnect(pcsc::Disposition::LeaveCard);
 
-        if let Some(reader) = reader_iter.next() {
+                    error!("multiple YubiKeys detected!");
-            if reader_iter.next().is_some() {
+                    return Err(Error::PcscError { inner: None });
-                error!("multiple YubiKeys detected!");
+                } else {
-                return Err(Error::PcscError { inner: None });
+                    yubikey = Some(yk_found);
+                }
             }
-
-            return reader.open();
         }
 
-        error!("no YubiKey detected!");
+        if let Some(yubikey) = yubikey {
-        Err(Error::NotFound)
+            // We found exactly one YubiKey that we could open, so we return it.
+            Ok(yubikey)
+        } else {
+            error!("no YubiKey detected!");
+            Err(Error::NotFound)
+        }
     }
 
     /// Open a YubiKey with a specific serial number.
@@ -243,7 +260,6 @@ impl YubiKey {
 
     /// Reconnect to a YubiKey.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn reconnect(&mut self) -> Result<()> {
         info!("trying to reconnect to current reader");
 
@@ -355,7 +371,7 @@ impl YubiKey {
         }
 
         // send a response to the cards challenge and a challenge of our own.
-        let response = mgm_key.decrypt(challenge.data()[4..12].try_into().unwrap());
+        let response = mgm_key.decrypt(challenge.data()[4..12].try_into()?);
 
         let mut data = [0u8; 22];
         data[0] = TAG_DYN_AUTH;
@@ -397,7 +413,6 @@ impl YubiKey {
 
     /// Deauthenticate.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn deauthenticate(&mut self) -> Result<()> {
         let txn = self.begin_transaction()?;
 
@@ -456,7 +471,6 @@ impl YubiKey {
 
     /// Set the number of PIN retries.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn set_pin_retries(&mut self, pin_tries: u8, puk_tries: u8) -> Result<()> {
         // Special case: if either retry count is 0, it's a successful no-op
         if pin_tries == 0 || puk_tries == 0 {
@@ -481,7 +495,6 @@ impl YubiKey {
     ///
     /// The default PIN code is `123456`.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn change_pin(&mut self, current_pin: &[u8], new_pin: &[u8]) -> Result<()> {
         {
             let txn = self.begin_transaction()?;
@@ -497,7 +510,6 @@ impl YubiKey {
 
     /// Set PIN last changed.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn set_pin_last_changed(yubikey: &mut YubiKey) -> Result<()> {
         let txn = yubikey.begin_transaction()?;
 
@@ -505,8 +517,7 @@ impl YubiKey {
 
         // TODO(tarcieri): double check this is little endian
         let tnow = SystemTime::now()
-            .duration_since(UNIX_EPOCH)
+            .duration_since(UNIX_EPOCH)?
-            .unwrap()
             .as_secs()
             .to_le_bytes();
 
@@ -533,7 +544,6 @@ impl YubiKey {
     ///
     /// The default PUK code is `12345678`.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn change_puk(&mut self, current_puk: &[u8], new_puk: &[u8]) -> Result<()> {
         let txn = self.begin_transaction()?;
         txn.change_ref(ChangeRefAction::ChangePuk, current_puk, new_puk)
@@ -541,7 +551,6 @@ impl YubiKey {
 
     /// Block PUK: permanently prevent the PIN from becoming unblocked.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn block_puk(&mut self) -> Result<()> {
         let mut puk = [0x30, 0x42, 0x41, 0x44, 0x46, 0x30, 0x30, 0x44];
         let mut tries_remaining: i32 = -1;
@@ -605,7 +614,6 @@ impl YubiKey {
     /// Unblock a Personal Identification Number (PIN) using a previously
     /// configured PIN Unblocking Key (PUK).
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn unblock_pin(&mut self, puk: &[u8], new_pin: &[u8]) -> Result<()> {
         let txn = self.begin_transaction()?;
         txn.change_ref(ChangeRefAction::UnblockPin, puk, new_pin)
@@ -613,7 +621,6 @@ impl YubiKey {
 
     /// Fetch an object from the YubiKey.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn fetch_object(&mut self, object_id: ObjectId) -> Result<Buffer> {
         let txn = self.begin_transaction()?;
         txn.fetch_object(object_id)
@@ -621,7 +628,6 @@ impl YubiKey {
 
     /// Save an object.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn save_object(&mut self, object_id: ObjectId, indata: &mut [u8]) -> Result<()> {
         let txn = self.begin_transaction()?;
         txn.save_object(object_id, indata)
@@ -629,7 +635,6 @@ impl YubiKey {
 
     /// Get an auth challenge.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn get_auth_challenge(&mut self) -> Result<[u8; 8]> {
         let txn = self.begin_transaction()?;
 
@@ -642,12 +647,15 @@ impl YubiKey {
             return Err(Error::AuthenticationError);
         }
 
-        Ok(response.data()[4..12].try_into().unwrap())
+        Ok(response
+            .data()
+            .get(4..12)
+            .ok_or(Error::SizeError)?
+            .try_into()?)
     }
 
     /// Verify an auth response.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn verify_auth_response(&mut self, response: [u8; 8]) -> Result<()> {
         let mut data = [0u8; 12];
         data[0] = 0x7c;
@@ -678,7 +686,6 @@ impl YubiKey {
     ///
     /// The reset function is only available when both pins are blocked.
     #[cfg(feature = "untested")]
-    #[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
     pub fn reset_device(&mut self) -> Result<()> {
         let templ = [0, Ins::Reset.code(), 0, 0];
         let txn = self.begin_transaction()?;

tests/integration.rs

@@ -6,14 +6,15 @@
 use log::trace;
 use once_cell::sync::Lazy;
 use rand_core::{OsRng, RngCore};
-use rsa::pkcs1v15;
+use rsa::{pkcs1v15, RsaPublicKey};
 use sha2::{Digest, Sha256};
 use signature::hazmat::PrehashVerifier;
-use std::{env, str::FromStr, sync::Mutex};
+use std::{env, str::FromStr, sync::Mutex, time::Duration};
-use x509::RelativeDistinguishedName;
+use x509_cert::{der::Encode, name::Name, serial_number::SerialNumber, time::Validity};
 use yubikey::{
     certificate,
-    certificate::{Certificate, PublicKeyInfo},
+    certificate::yubikey_signer,
+    certificate::Certificate,
     piv::{self, AlgorithmId, Key, ManagementSlotId, RetiredSlotId, SlotId},
     Error, MgmKey, PinPolicy, Serial, TouchPolicy, YubiKey,
 };
@@ -147,7 +148,7 @@ fn test_set_mgmkey() {
 // Certificate support
 //
 
-fn generate_self_signed_cert(algorithm: AlgorithmId) -> Certificate {
+fn generate_self_signed_cert<KT: yubikey_signer::KeyType>() -> Certificate {
     let mut yubikey = YUBIKEY.lock().unwrap();
 
     assert!(yubikey.verify_pin(b"123456").is_ok());
@@ -159,25 +160,28 @@ fn generate_self_signed_cert(algorithm: AlgorithmId) -> Certificate {
     let generated = piv::generate(
         &mut yubikey,
         slot,
-        algorithm,
+        KT::ALGORITHM,
         PinPolicy::Default,
         TouchPolicy::Default,
     )
     .unwrap();
 
-    let mut serial = [0u8; 20];
+    // 0x80 0x00 ... (20bytes) is invalid because of high MSB (serial will keep the sign)
+    // we'll limit ourselves to 19 bytes serial.
+    let mut serial = [0u8; 19];
     OsRng.fill_bytes(&mut serial);
+    let serial = SerialNumber::new(&serial[..]).expect("serial can't be more than 20 bytes long");
+    let validity = Validity::from_now(Duration::new(500000, 0)).unwrap();
 
     // Generate a self-signed certificate for the new key.
-    let extensions: &[x509::Extension<'_, &[u64]>] = &[];
+    let cert_result = Certificate::generate_self_signed::<_, KT>(
-    let cert_result = Certificate::generate_self_signed(
         &mut yubikey,
         slot,
         serial,
-        None,
+        validity,
-        &[RelativeDistinguishedName::common_name("testSubject")],
+        Name::from_str("CN=testSubject").expect("parse name"),
         generated,
-        extensions,
+        |_builder| Ok(()),
     );
 
     assert!(cert_result.is_ok());
@@ -189,18 +193,16 @@ fn generate_self_signed_cert(algorithm: AlgorithmId) -> Certificate {
 #[test]
 #[ignore]
 fn generate_self_signed_rsa_cert() {
-    let cert = generate_self_signed_cert(AlgorithmId::Rsa1024);
+    let cert = generate_self_signed_cert::<yubikey_signer::YubiRsa<yubikey_signer::Rsa1024>>();
 
     //
     // Verify that the certificate is signed correctly
     //
 
-    let pubkey = match cert.subject_pki() {
+    let pubkey = RsaPublicKey::try_from(cert.subject_pki()).expect("valid rsa key");
-        PublicKeyInfo::Rsa { pubkey, .. } => pkcs1v15::VerifyingKey::<Sha256>::from(pubkey.clone()),
+    let pubkey = pkcs1v15::VerifyingKey::<Sha256>::new(pubkey);
-        _ => unreachable!(),
-    };
 
-    let data = cert.as_ref();
+    let data = cert.cert.to_der().expect("serialize certificate");
     let tbs_cert_len = u16::from_be_bytes(data[6..8].try_into().unwrap()) as usize;
     let msg = &data[4..8 + tbs_cert_len];
     let sig = pkcs1v15::Signature::try_from(&data[data.len() - 128..]).unwrap();
@@ -212,24 +214,20 @@ fn generate_self_signed_rsa_cert() {
 #[test]
 #[ignore]
 fn generate_self_signed_ec_cert() {
-    let cert = generate_self_signed_cert(AlgorithmId::EccP256);
+    let cert = generate_self_signed_cert::<p256::NistP256>();
 
     //
     // Verify that the certificate is signed correctly
     //
 
-    let pubkey = match cert.subject_pki() {
+    let vk = p256::ecdsa::VerifyingKey::try_from(cert.subject_pki()).expect("ecdsa key expected");
-        PublicKeyInfo::EcP256(pubkey) => pubkey,
-        _ => unreachable!(),
-    };
 
-    let data = cert.as_ref();
+    let data = cert.cert.to_der().expect("serialize certificate");
     let tbs_cert_len = data[6] as usize;
     let sig_algo_len = data[7 + tbs_cert_len + 1] as usize;
     let sig_start = 7 + tbs_cert_len + 2 + sig_algo_len + 3;
     let msg = &data[4..7 + tbs_cert_len];
     let sig = p256::ecdsa::Signature::from_der(&data[sig_start..]).unwrap();
-    let vk = p256::ecdsa::VerifyingKey::from_sec1_bytes(pubkey.as_bytes()).unwrap();
 
     use p256::ecdsa::signature::Verifier;
     assert!(vk.verify(msg, &sig).is_ok());
@@ -269,11 +267,11 @@ fn test_slot_id_display() {
 
     assert_eq!(
         format!("{}", SlotId::Management(ManagementSlotId::Pin)),
-        "PIN"
+        "Pin"
     );
     assert_eq!(
         format!("{}", SlotId::Management(ManagementSlotId::Puk)),
-        "PUK"
+        "Puk"
     );
     assert_eq!(
         format!("{}", SlotId::Management(ManagementSlotId::Management)),
@@ -305,53 +303,14 @@ fn test_read_metadata() {
     )
     .unwrap();
 
-    let metadata = piv::metadata(&mut yubikey, slot).unwrap();
+    match piv::metadata(&mut yubikey, slot) {
-
+        Ok(metadata) => assert_eq!(metadata.public, Some(generated)),
-    assert_eq!(metadata.public, Some(generated));
+        Err(Error::NotSupported) => {
-}
+            // Some YubiKeys don't support metadata
-
+            eprintln!("metadata not supported by this YubiKey");
-#[test]
+        }
-#[ignore]
+        Err(err) => panic!("{}", err),
-fn test_serial_string_conversions() {
+    }
-    //2^152+1
-    let serial: [u8; 20] = [
-        0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-        0x00, 0x00, 0x00, 0x00, 0x01,
-    ];
-
-    let s = certificate::Serial::from(serial);
-    assert_eq!(
-        s.as_x509_int(),
-        "5708990770823839524233143877797980545530986497"
-    );
-    assert_eq!(
-        s.as_x509_hex(),
-        "01:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:01"
-    );
-
-    let serial2: [u8; 20] = [
-        0xA1, 0xF3, 0x02, 0x30, 0x76, 0x01, 0x32, 0x48, 0x09, 0x9C, 0x10, 0xAA, 0x3F, 0xA0, 0x54,
-        0x0D, 0xC0, 0xB7, 0x65, 0x01,
-    ];
-
-    let s2 = certificate::Serial::from(serial2);
-    assert_eq!(
-        s2.as_x509_int(),
-        "924566785900861696177829411010986812227211191553"
-    );
-    assert_eq!(
-        s2.as_x509_hex(),
-        "a1:f3:02:30:76:01:32:48:09:9c:10:aa:3f:a0:54:0d:c0:b7:65:01"
-    );
-
-    let serial3: [u8; 20] = [
-        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xAA, 0x3F, 0xA0, 0x54,
-        0x0D, 0xC0, 0xB7, 0x65, 0x01,
-    ];
-
-    let s3 = certificate::Serial::from(serial3);
-    assert_eq!(s3.as_x509_int(), "3140531249369331492097");
-    assert_eq!(s3.as_x509_hex(), "aa:3f:a0:54:0d:c0:b7:65:01");
 }
 
 #[test]