/rust/registry/src/index.crates.io-6f17d22bba15001f/rustls-webpki-0.103.4/src/error.rs

Source (jump to first uncovered line)
// Copyright 2015 Brian Smith.
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

#[cfg(feature = "alloc")]
use alloc::string::String;
#[cfg(feature = "alloc")]
use alloc::vec::Vec;
use core::fmt;
use core::ops::ControlFlow;

use pki_types::UnixTime;
#[cfg(feature = "alloc")]
use pki_types::{AlgorithmIdentifier, ServerName};

use crate::verify_cert::RequiredEkuNotFoundContext;

/// An error that occurs during certificate validation or name validation.
#[derive(Clone, Debug, PartialEq, Eq)]
#[non_exhaustive]
pub enum Error {
    /// The encoding of some ASN.1 DER-encoded item is invalid.
    BadDer,

    /// The encoding of an ASN.1 DER-encoded time is invalid.
    BadDerTime,

    /// A CA certificate is being used as an end-entity certificate.
    CaUsedAsEndEntity,

    /// The certificate is expired; i.e. the time it is being validated for is
    /// later than the certificate's notAfter time.
    CertExpired {
        /// The validation time.
        time: UnixTime,
        /// The notAfter time of the certificate.
        not_after: UnixTime,
    },

    /// The certificate is not valid for the name it is being validated for.
    CertNotValidForName(InvalidNameContext),

    /// The certificate is not valid yet; i.e. the time it is being validated
    /// for is earlier than the certificate's notBefore time.
    CertNotValidYet {
        /// The validation time.
        time: UnixTime,
        /// The notBefore time of the certificate.
        not_before: UnixTime,
    },

    /// The certificate, or one of its issuers, has been revoked.
    CertRevoked,

    /// The CRL is expired; i.e. the verification time is not before the time
    /// in the CRL nextUpdate field.
    CrlExpired {
        /// The validation time.
        time: UnixTime,
        /// The nextUpdate time of the CRL.
        next_update: UnixTime,
    },

    /// An end-entity certificate is being used as a CA certificate.
    EndEntityUsedAsCa,

    /// An X.509 extension is invalid.
    ExtensionValueInvalid,

    /// The certificate validity period (notBefore, notAfter) is invalid; e.g.
    /// the notAfter time is earlier than the notBefore time.
    InvalidCertValidity,

    /// A CRL number extension was invalid:
    ///  - it was mis-encoded
    ///  - it was negative
    ///  - it was too long
    InvalidCrlNumber,

    /// A iPAddress name constraint was invalid:
    /// - it had a sparse network mask (ie, cannot be written in CIDR form).
    /// - it was too long or short
    InvalidNetworkMaskConstraint,

    /// A serial number was invalid:
    ///  - it was misencoded
    ///  - it was negative
    ///  - it was too long
    InvalidSerialNumber,

    /// The CRL signature is invalid for the issuer's public key.
    InvalidCrlSignatureForPublicKey,

    /// The signature is invalid for the given public key.
    InvalidSignatureForPublicKey,

    /// A CRL was signed by an issuer that has a KeyUsage bitstring that does not include
    /// the cRLSign key usage bit.
    IssuerNotCrlSigner,

    /// A presented or reference DNS identifier was malformed, potentially
    /// containing invalid characters or invalid labels.
    MalformedDnsIdentifier,

    /// The certificate extensions are malformed.
    ///
    /// In particular, webpki requires the DNS name(s) be in the subjectAltName
    /// extension as required by the CA/Browser Forum Baseline Requirements
    /// and as recommended by RFC6125.
    MalformedExtensions,

    /// A name constraint was malformed, potentially containing invalid characters or
    /// invalid labels.
    MalformedNameConstraint,

    /// The maximum number of name constraint comparisons has been reached.
    MaximumNameConstraintComparisonsExceeded,

    /// The maximum number of internal path building calls has been reached. Path complexity is too great.
    MaximumPathBuildCallsExceeded,

    /// The path search was terminated because it became too deep.
    MaximumPathDepthExceeded,

    /// The maximum number of signature checks has been reached. Path complexity is too great.
    MaximumSignatureChecksExceeded,

    /// The certificate violates one or more name constraints.
    NameConstraintViolation,

    /// The certificate violates one or more path length constraints.
    PathLenConstraintViolated,

    /// The certificate is not valid for the Extended Key Usage for which it is
    /// being validated.
    #[deprecated(since = "0.103.2", note = "use RequiredEkuNotFoundContext instead")]
    RequiredEkuNotFound,

    /// The certificate is not valid for the Extended Key Usage for which it is
    /// being validated.
    RequiredEkuNotFoundContext(RequiredEkuNotFoundContext),

    /// The algorithm in the TBSCertificate "signature" field of a certificate
    /// does not match the algorithm in the signature of the certificate.
    SignatureAlgorithmMismatch,

    /// Trailing data was found while parsing DER-encoded input for the named type.
    TrailingData(DerTypeId),

    /// A valid issuer for the certificate could not be found.
    UnknownIssuer,

    /// The certificate's revocation status could not be determined.
    UnknownRevocationStatus,

    /// The certificate is not a v3 X.509 certificate.
    ///
    /// This error may be also reported if the certificate version field
    /// is malformed.
    UnsupportedCertVersion,

    /// The certificate contains an unsupported critical extension.
    UnsupportedCriticalExtension,

    /// The CRL contains an issuing distribution point with no distribution point name,
    /// or a distribution point name relative to an issuer.
    UnsupportedCrlIssuingDistributionPoint,

    /// The CRL is not a v2 X.509 CRL.
    ///
    /// The RFC 5280 web PKI profile mandates only version 2 be used. See section
    /// 5.1.2.1 for more information.
    ///
    /// This error may also be reported if the CRL version field is malformed.
    UnsupportedCrlVersion,

    /// The CRL is an unsupported "delta" CRL.
    UnsupportedDeltaCrl,

    /// The CRL contains unsupported "indirect" entries.
    UnsupportedIndirectCrl,

    /// The `ServerName` contained an unsupported type of value.
    UnsupportedNameType,

    /// The revocation reason is not in the set of supported revocation reasons.
    UnsupportedRevocationReason,

    /// The CRL is partitioned by revocation reasons.
    UnsupportedRevocationReasonsPartitioning,

    /// The signature algorithm for a signature over a CRL is not in the set of supported
    /// signature algorithms given.
    #[deprecated(
        since = "0.103.4",
        note = "use UnsupportedCrlSignatureAlgorithmContext instead"
    )]
    UnsupportedCrlSignatureAlgorithm,

    /// The signature algorithm for a signature is not in the set of supported
    /// signature algorithms given.
    UnsupportedCrlSignatureAlgorithmContext(UnsupportedSignatureAlgorithmContext),

    /// The signature algorithm for a signature is not in the set of supported
    /// signature algorithms given.
    #[deprecated(
        since = "0.103.4",
        note = "use UnsupportedSignatureAlgorithmContext instead"
    )]
    UnsupportedSignatureAlgorithm,

    /// The signature algorithm for a signature is not in the set of supported
    /// signature algorithms given.
    UnsupportedSignatureAlgorithmContext(UnsupportedSignatureAlgorithmContext),

    /// The CRL signature's algorithm does not match the algorithm of the issuer
    /// public key it is being validated for. This may be because the public key
    /// algorithm's OID isn't recognized (e.g. DSA), or the public key
    /// algorithm's parameters don't match the supported parameters for that
    /// algorithm (e.g. ECC keys for unsupported curves), or the public key
    /// algorithm and the signature algorithm simply don't match (e.g.
    /// verifying an RSA signature with an ECC public key).
    #[deprecated(
        since = "0.103.4",
        note = "use UnsupportedCrlSignatureAlgorithmForPublicKeyContext instead"
    )]
    UnsupportedCrlSignatureAlgorithmForPublicKey,

    /// The signature's algorithm does not match the algorithm of the public
    /// key it is being validated for. This may be because the public key
    /// algorithm's OID isn't recognized (e.g. DSA), or the public key
    /// algorithm's parameters don't match the supported parameters for that
    /// algorithm (e.g. ECC keys for unsupported curves), or the public key
    /// algorithm and the signature algorithm simply don't match (e.g.
    /// verifying an RSA signature with an ECC public key).
    UnsupportedCrlSignatureAlgorithmForPublicKeyContext(
        UnsupportedSignatureAlgorithmForPublicKeyContext,
    ),

    /// The signature's algorithm does not match the algorithm of the public
    /// key it is being validated for. This may be because the public key
    /// algorithm's OID isn't recognized (e.g. DSA), or the public key
    /// algorithm's parameters don't match the supported parameters for that
    /// algorithm (e.g. ECC keys for unsupported curves), or the public key
    /// algorithm and the signature algorithm simply don't match (e.g.
    /// verifying an RSA signature with an ECC public key).
    #[deprecated(
        since = "0.103.4",
        note = "use UnsupportedSignatureAlgorithmForPublicKeyContext instead"
    )]
    UnsupportedSignatureAlgorithmForPublicKey,

    /// The signature's algorithm does not match the algorithm of the public
    /// key it is being validated for. This may be because the public key
    /// algorithm's OID isn't recognized (e.g. DSA), or the public key
    /// algorithm's parameters don't match the supported parameters for that
    /// algorithm (e.g. ECC keys for unsupported curves), or the public key
    /// algorithm and the signature algorithm simply don't match (e.g.
    /// verifying an RSA signature with an ECC public key).
    UnsupportedSignatureAlgorithmForPublicKeyContext(
        UnsupportedSignatureAlgorithmForPublicKeyContext,
    ),
}

impl Error {
    // Compare the Error with the new error by rank, returning the higher rank of the two as
    // the most specific error.
    pub(crate) fn most_specific(self, new: Self) -> Self {
        // Assign an error a numeric value ranking it by specificity.
        if self.rank() >= new.rank() { self } else { new }
    }

    // Return a numeric indication of how specific the error is, where an error with a higher rank
    // is considered more useful to an end user than an error with a lower rank. This is used by
    // Error::most_specific to compare two errors in order to return which is more specific.
    #[allow(clippy::as_conversions)] // We won't exceed u32 errors.
    pub(crate) fn rank(&self) -> u32 {
        match &self {
            // Errors related to certificate validity
            Self::CertNotValidYet { .. } | Self::CertExpired { .. } => 290,
            Self::CertNotValidForName(_) => 280,
            Self::CertRevoked | Self::UnknownRevocationStatus | Self::CrlExpired { .. } => 270,
            Self::InvalidCrlSignatureForPublicKey | Self::InvalidSignatureForPublicKey => 260,
            Self::SignatureAlgorithmMismatch => 250,
            #[allow(deprecated)]
            Self::RequiredEkuNotFound | Self::RequiredEkuNotFoundContext(_) => 240,
            Self::NameConstraintViolation => 230,
            Self::PathLenConstraintViolated => 220,
            Self::CaUsedAsEndEntity | Self::EndEntityUsedAsCa => 210,
            Self::IssuerNotCrlSigner => 200,

            // Errors related to supported features used in an invalid way.
            Self::InvalidCertValidity => 190,
            Self::InvalidNetworkMaskConstraint => 180,
            Self::InvalidSerialNumber => 170,
            Self::InvalidCrlNumber => 160,

            // Errors related to unsupported features.
            #[allow(deprecated)]
            Self::UnsupportedCrlSignatureAlgorithmForPublicKey
            | Self::UnsupportedCrlSignatureAlgorithmForPublicKeyContext(_)
            | Self::UnsupportedSignatureAlgorithmForPublicKey
            | Self::UnsupportedSignatureAlgorithmForPublicKeyContext(_) => 150,
            #[allow(deprecated)]
            Self::UnsupportedCrlSignatureAlgorithm
            | Self::UnsupportedCrlSignatureAlgorithmContext(_)
            | Self::UnsupportedSignatureAlgorithm
            | Self::UnsupportedSignatureAlgorithmContext(_) => 140,
            Self::UnsupportedCriticalExtension => 130,
            Self::UnsupportedCertVersion => 130,
            Self::UnsupportedCrlVersion => 120,
            Self::UnsupportedDeltaCrl => 110,
            Self::UnsupportedIndirectCrl => 100,
            Self::UnsupportedNameType => 95,
            Self::UnsupportedRevocationReason => 90,
            Self::UnsupportedRevocationReasonsPartitioning => 80,
            Self::UnsupportedCrlIssuingDistributionPoint => 70,
            Self::MaximumPathDepthExceeded => 61,

            // Errors related to malformed data.
            Self::MalformedDnsIdentifier => 60,
            Self::MalformedNameConstraint => 50,
            Self::MalformedExtensions | Self::TrailingData(_) => 40,
            Self::ExtensionValueInvalid => 30,

            // Generic DER errors.
            Self::BadDerTime => 20,
            Self::BadDer => 10,

            // Special case errors - not subject to ranking.
            Self::MaximumSignatureChecksExceeded => 0,
            Self::MaximumPathBuildCallsExceeded => 0,
            Self::MaximumNameConstraintComparisonsExceeded => 0,

            // Default catch all error - should be renamed in the future.
            Self::UnknownIssuer => 0,
        }
    }

    /// Returns true for errors that should be considered fatal during path building. Errors of
    /// this class should halt any further path building and be returned immediately.
    #[inline]
    pub(crate) fn is_fatal(&self) -> bool {
        matches!(
            self,
            Self::MaximumSignatureChecksExceeded
                | Self::MaximumPathBuildCallsExceeded
                | Self::MaximumNameConstraintComparisonsExceeded
        )
    }
}

impl From<Error> for ControlFlow<Error, Error> {
    fn from(value: Error) -> Self {
        match value {
            // If an error is fatal, we've exhausted the potential for continued search.
            err if err.is_fatal() => Self::Break(err),
            // Otherwise we've rejected one candidate chain, but may continue to search for others.
            err => Self::Continue(err),
        }
    }
}

impl fmt::Display for Error {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "{self:?}")
    }
}

#[cfg(feature = "std")]
impl ::std::error::Error for Error {}

/// Additional context for the `CertNotValidForName` error variant.
///
/// The contents of this type depend on whether the `alloc` feature is enabled.
#[derive(Clone, Debug, PartialEq, Eq)]
pub struct InvalidNameContext {
    /// Expected server name.
    #[cfg(feature = "alloc")]
    pub expected: ServerName<'static>,
    /// The names presented in the end entity certificate.
    ///
    /// These are the subject names as present in the leaf certificate and may contain DNS names
    /// with or without a wildcard label as well as IP address names.
    #[cfg(feature = "alloc")]
    pub presented: Vec<String>,
}

/// Additional context for the `UnsupportedSignatureAlgorithmForPublicKey` error variant.
///
/// The contents of this type depend on whether the `alloc` feature is enabled.
#[derive(Clone, Debug, PartialEq, Eq)]
pub struct UnsupportedSignatureAlgorithmForPublicKeyContext {
    /// The signature algorithm OID.
    #[cfg(feature = "alloc")]
    pub signature_algorithm_id: Vec<u8>,
    /// The public key algorithm OID.
    #[cfg(feature = "alloc")]
    pub public_key_algorithm_id: Vec<u8>,
}

/// Additional context for the `UnsupportedSignatureAlgorithm` error variant.
///
/// The contents of this type depend on whether the `alloc` feature is enabled.
#[derive(Clone, Debug, PartialEq, Eq)]
pub struct UnsupportedSignatureAlgorithmContext {
    /// The signature algorithm OID that was unsupported.
    #[cfg(feature = "alloc")]
    pub signature_algorithm_id: Vec<u8>,
    /// Supported algorithms that were available for signature verification.
    #[cfg(feature = "alloc")]
    pub supported_algorithms: Vec<AlgorithmIdentifier>,
}

/// Trailing data was found while parsing DER-encoded input for the named type.
#[allow(missing_docs)]
#[non_exhaustive]
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum DerTypeId {
    BitString,
    Bool,
    Certificate,
    CertificateExtensions,
    CertificateTbsCertificate,
    CertRevocationList,
    CertRevocationListExtension,
    CrlDistributionPoint,
    CommonNameInner,
    CommonNameOuter,
    DistributionPointName,
    Extension,
    GeneralName,
    RevocationReason,
    Signature,
    SignatureAlgorithm,
    SignedData,
    SubjectPublicKeyInfo,
    Time,
    TrustAnchorV1,
    TrustAnchorV1TbsCertificate,
    U8,
    RevokedCertificate,
    RevokedCertificateExtension,
    RevokedCertEntry,
    IssuingDistributionPoint,
}

Coverage Report

Created: 2025-08-29 06:34

Line	Count	Source (jump to first uncovered line)
1		// Copyright 2015 Brian Smith.
2		//
3		// Permission to use, copy, modify, and/or distribute this software for any
4		// purpose with or without fee is hereby granted, provided that the above
5		// copyright notice and this permission notice appear in all copies.
6		//
7		// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
8		// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9		// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
10		// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11		// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
12		// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
13		// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
14
15		#[cfg(feature = "alloc")]
16		use alloc::string::String;
17		#[cfg(feature = "alloc")]
18		use alloc::vec::Vec;
19		use core::fmt;
20		use core::ops::ControlFlow;
21
22		use pki_types::UnixTime;
23		#[cfg(feature = "alloc")]
24		use pki_types::{AlgorithmIdentifier, ServerName};
25
26		use crate::verify_cert::RequiredEkuNotFoundContext;
27
28		/// An error that occurs during certificate validation or name validation.
29		#[derive(Clone, Debug, PartialEq, Eq)]
30		#[non_exhaustive]
31		pub enum Error {
32		/// The encoding of some ASN.1 DER-encoded item is invalid.
33		BadDer,
34
35		/// The encoding of an ASN.1 DER-encoded time is invalid.
36		BadDerTime,
37
38		/// A CA certificate is being used as an end-entity certificate.
39		CaUsedAsEndEntity,
40
41		/// The certificate is expired; i.e. the time it is being validated for is
42		/// later than the certificate's notAfter time.
43		CertExpired {
44		/// The validation time.
45		time: UnixTime,
46		/// The notAfter time of the certificate.
47		not_after: UnixTime,
48		},
49
50		/// The certificate is not valid for the name it is being validated for.
51		CertNotValidForName(InvalidNameContext),
52
53		/// The certificate is not valid yet; i.e. the time it is being validated
54		/// for is earlier than the certificate's notBefore time.
55		CertNotValidYet {
56		/// The validation time.
57		time: UnixTime,
58		/// The notBefore time of the certificate.
59		not_before: UnixTime,
60		},
61
62		/// The certificate, or one of its issuers, has been revoked.
63		CertRevoked,
64
65		/// The CRL is expired; i.e. the verification time is not before the time
66		/// in the CRL nextUpdate field.
67		CrlExpired {
68		/// The validation time.
69		time: UnixTime,
70		/// The nextUpdate time of the CRL.
71		next_update: UnixTime,
72		},
73
74		/// An end-entity certificate is being used as a CA certificate.
75		EndEntityUsedAsCa,
76
77		/// An X.509 extension is invalid.
78		ExtensionValueInvalid,
79
80		/// The certificate validity period (notBefore, notAfter) is invalid; e.g.
81		/// the notAfter time is earlier than the notBefore time.
82		InvalidCertValidity,
83
84		/// A CRL number extension was invalid:
85		/// - it was mis-encoded
86		/// - it was negative
87		/// - it was too long
88		InvalidCrlNumber,
89
90		/// A iPAddress name constraint was invalid:
91		/// - it had a sparse network mask (ie, cannot be written in CIDR form).
92		/// - it was too long or short
93		InvalidNetworkMaskConstraint,
94
95		/// A serial number was invalid:
96		/// - it was misencoded
97		/// - it was negative
98		/// - it was too long
99		InvalidSerialNumber,
100
101		/// The CRL signature is invalid for the issuer's public key.
102		InvalidCrlSignatureForPublicKey,
103
104		/// The signature is invalid for the given public key.
105		InvalidSignatureForPublicKey,
106
107		/// A CRL was signed by an issuer that has a KeyUsage bitstring that does not include
108		/// the cRLSign key usage bit.
109		IssuerNotCrlSigner,
110
111		/// A presented or reference DNS identifier was malformed, potentially
112		/// containing invalid characters or invalid labels.
113		MalformedDnsIdentifier,
114
115		/// The certificate extensions are malformed.
116		///
117		/// In particular, webpki requires the DNS name(s) be in the subjectAltName
118		/// extension as required by the CA/Browser Forum Baseline Requirements
119		/// and as recommended by RFC6125.
120		MalformedExtensions,
121
122		/// A name constraint was malformed, potentially containing invalid characters or
123		/// invalid labels.
124		MalformedNameConstraint,
125
126		/// The maximum number of name constraint comparisons has been reached.
127		MaximumNameConstraintComparisonsExceeded,
128
129		/// The maximum number of internal path building calls has been reached. Path complexity is too great.
130		MaximumPathBuildCallsExceeded,
131
132		/// The path search was terminated because it became too deep.
133		MaximumPathDepthExceeded,
134
135		/// The maximum number of signature checks has been reached. Path complexity is too great.
136		MaximumSignatureChecksExceeded,
137
138		/// The certificate violates one or more name constraints.
139		NameConstraintViolation,
140
141		/// The certificate violates one or more path length constraints.
142		PathLenConstraintViolated,
143
144		/// The certificate is not valid for the Extended Key Usage for which it is
145		/// being validated.
146		#[deprecated(since = "0.103.2", note = "use RequiredEkuNotFoundContext instead")]
147		RequiredEkuNotFound,
148
149		/// The certificate is not valid for the Extended Key Usage for which it is
150		/// being validated.
151		RequiredEkuNotFoundContext(RequiredEkuNotFoundContext),
152
153		/// The algorithm in the TBSCertificate "signature" field of a certificate
154		/// does not match the algorithm in the signature of the certificate.
155		SignatureAlgorithmMismatch,
156
157		/// Trailing data was found while parsing DER-encoded input for the named type.
158		TrailingData(DerTypeId),
159
160		/// A valid issuer for the certificate could not be found.
161		UnknownIssuer,
162
163		/// The certificate's revocation status could not be determined.
164		UnknownRevocationStatus,
165
166		/// The certificate is not a v3 X.509 certificate.
167		///
168		/// This error may be also reported if the certificate version field
169		/// is malformed.
170		UnsupportedCertVersion,
171
172		/// The certificate contains an unsupported critical extension.
173		UnsupportedCriticalExtension,
174
175		/// The CRL contains an issuing distribution point with no distribution point name,
176		/// or a distribution point name relative to an issuer.
177		UnsupportedCrlIssuingDistributionPoint,
178
179		/// The CRL is not a v2 X.509 CRL.
180		///
181		/// The RFC 5280 web PKI profile mandates only version 2 be used. See section
182		/// 5.1.2.1 for more information.
183		///
184		/// This error may also be reported if the CRL version field is malformed.
185		UnsupportedCrlVersion,
186
187		/// The CRL is an unsupported "delta" CRL.
188		UnsupportedDeltaCrl,
189
190		/// The CRL contains unsupported "indirect" entries.
191		UnsupportedIndirectCrl,
192
193		/// The `ServerName` contained an unsupported type of value.
194		UnsupportedNameType,
195
196		/// The revocation reason is not in the set of supported revocation reasons.
197		UnsupportedRevocationReason,
198
199		/// The CRL is partitioned by revocation reasons.
200		UnsupportedRevocationReasonsPartitioning,
201
202		/// The signature algorithm for a signature over a CRL is not in the set of supported
203		/// signature algorithms given.
204		#[deprecated(
205		since = "0.103.4",
206		note = "use UnsupportedCrlSignatureAlgorithmContext instead"
207		)]
208		UnsupportedCrlSignatureAlgorithm,
209
210		/// The signature algorithm for a signature is not in the set of supported
211		/// signature algorithms given.
212		UnsupportedCrlSignatureAlgorithmContext(UnsupportedSignatureAlgorithmContext),
213
214		/// The signature algorithm for a signature is not in the set of supported
215		/// signature algorithms given.
216		#[deprecated(
217		since = "0.103.4",
218		note = "use UnsupportedSignatureAlgorithmContext instead"
219		)]
220		UnsupportedSignatureAlgorithm,
221
222		/// The signature algorithm for a signature is not in the set of supported
223		/// signature algorithms given.
224		UnsupportedSignatureAlgorithmContext(UnsupportedSignatureAlgorithmContext),
225
226		/// The CRL signature's algorithm does not match the algorithm of the issuer
227		/// public key it is being validated for. This may be because the public key
228		/// algorithm's OID isn't recognized (e.g. DSA), or the public key
229		/// algorithm's parameters don't match the supported parameters for that
230		/// algorithm (e.g. ECC keys for unsupported curves), or the public key
231		/// algorithm and the signature algorithm simply don't match (e.g.
232		/// verifying an RSA signature with an ECC public key).
233		#[deprecated(
234		since = "0.103.4",
235		note = "use UnsupportedCrlSignatureAlgorithmForPublicKeyContext instead"
236		)]
237		UnsupportedCrlSignatureAlgorithmForPublicKey,
238
239		/// The signature's algorithm does not match the algorithm of the public
240		/// key it is being validated for. This may be because the public key
241		/// algorithm's OID isn't recognized (e.g. DSA), or the public key
242		/// algorithm's parameters don't match the supported parameters for that
243		/// algorithm (e.g. ECC keys for unsupported curves), or the public key
244		/// algorithm and the signature algorithm simply don't match (e.g.
245		/// verifying an RSA signature with an ECC public key).
246		UnsupportedCrlSignatureAlgorithmForPublicKeyContext(
247		UnsupportedSignatureAlgorithmForPublicKeyContext,
248		),
249
250		/// The signature's algorithm does not match the algorithm of the public
251		/// key it is being validated for. This may be because the public key
252		/// algorithm's OID isn't recognized (e.g. DSA), or the public key
253		/// algorithm's parameters don't match the supported parameters for that
254		/// algorithm (e.g. ECC keys for unsupported curves), or the public key
255		/// algorithm and the signature algorithm simply don't match (e.g.
256		/// verifying an RSA signature with an ECC public key).
257		#[deprecated(
258		since = "0.103.4",
259		note = "use UnsupportedSignatureAlgorithmForPublicKeyContext instead"
260		)]
261		UnsupportedSignatureAlgorithmForPublicKey,
262
263		/// The signature's algorithm does not match the algorithm of the public
264		/// key it is being validated for. This may be because the public key
265		/// algorithm's OID isn't recognized (e.g. DSA), or the public key
266		/// algorithm's parameters don't match the supported parameters for that
267		/// algorithm (e.g. ECC keys for unsupported curves), or the public key
268		/// algorithm and the signature algorithm simply don't match (e.g.
269		/// verifying an RSA signature with an ECC public key).
270		UnsupportedSignatureAlgorithmForPublicKeyContext(
271		UnsupportedSignatureAlgorithmForPublicKeyContext,
272		),
273		}
274
275		impl Error {
276		// Compare the Error with the new error by rank, returning the higher rank of the two as
277		// the most specific error.
278	0	pub(crate) fn most_specific(self, new: Self) -> Self {
279	0	// Assign an error a numeric value ranking it by specificity.
280	0	if self.rank() >= new.rank() { self } else { new }
281	0	}
282
283		// Return a numeric indication of how specific the error is, where an error with a higher rank
284		// is considered more useful to an end user than an error with a lower rank. This is used by
285		// Error::most_specific to compare two errors in order to return which is more specific.
286		#[allow(clippy::as_conversions)] // We won't exceed u32 errors.
287	0	pub(crate) fn rank(&self) -> u32 {
288	0	match &self {
289		// Errors related to certificate validity
290	0	Self::CertNotValidYet { .. } \| Self::CertExpired { .. } => 290,
291	0	Self::CertNotValidForName(_) => 280,
292	0	Self::CertRevoked \| Self::UnknownRevocationStatus \| Self::CrlExpired { .. } => 270,
293	0	Self::InvalidCrlSignatureForPublicKey \| Self::InvalidSignatureForPublicKey => 260,
294	0	Self::SignatureAlgorithmMismatch => 250,
295		#[allow(deprecated)]
296	0	Self::RequiredEkuNotFound \| Self::RequiredEkuNotFoundContext(_) => 240,
297	0	Self::NameConstraintViolation => 230,
298	0	Self::PathLenConstraintViolated => 220,
299	0	Self::CaUsedAsEndEntity \| Self::EndEntityUsedAsCa => 210,
300	0	Self::IssuerNotCrlSigner => 200,
301
302		// Errors related to supported features used in an invalid way.
303	0	Self::InvalidCertValidity => 190,
304	0	Self::InvalidNetworkMaskConstraint => 180,
305	0	Self::InvalidSerialNumber => 170,
306	0	Self::InvalidCrlNumber => 160,
307
308		// Errors related to unsupported features.
309		#[allow(deprecated)]
310		Self::UnsupportedCrlSignatureAlgorithmForPublicKey
311		\| Self::UnsupportedCrlSignatureAlgorithmForPublicKeyContext(_)
312		\| Self::UnsupportedSignatureAlgorithmForPublicKey
313	0	\| Self::UnsupportedSignatureAlgorithmForPublicKeyContext(_) => 150,
314		#[allow(deprecated)]
315		Self::UnsupportedCrlSignatureAlgorithm
316		\| Self::UnsupportedCrlSignatureAlgorithmContext(_)
317		\| Self::UnsupportedSignatureAlgorithm
318	0	\| Self::UnsupportedSignatureAlgorithmContext(_) => 140,
319	0	Self::UnsupportedCriticalExtension => 130,
320	0	Self::UnsupportedCertVersion => 130,
321	0	Self::UnsupportedCrlVersion => 120,
322	0	Self::UnsupportedDeltaCrl => 110,
323	0	Self::UnsupportedIndirectCrl => 100,
324	0	Self::UnsupportedNameType => 95,
325	0	Self::UnsupportedRevocationReason => 90,
326	0	Self::UnsupportedRevocationReasonsPartitioning => 80,
327	0	Self::UnsupportedCrlIssuingDistributionPoint => 70,
328	0	Self::MaximumPathDepthExceeded => 61,
329
330		// Errors related to malformed data.
331	0	Self::MalformedDnsIdentifier => 60,
332	0	Self::MalformedNameConstraint => 50,
333	0	Self::MalformedExtensions \| Self::TrailingData(_) => 40,
334	0	Self::ExtensionValueInvalid => 30,
335
336		// Generic DER errors.
337	0	Self::BadDerTime => 20,
338	0	Self::BadDer => 10,
339
340		// Special case errors - not subject to ranking.
341	0	Self::MaximumSignatureChecksExceeded => 0,
342	0	Self::MaximumPathBuildCallsExceeded => 0,
343	0	Self::MaximumNameConstraintComparisonsExceeded => 0,
344
345		// Default catch all error - should be renamed in the future.
346	0	Self::UnknownIssuer => 0,
347		}
348	0	}
349
350		/// Returns true for errors that should be considered fatal during path building. Errors of
351		/// this class should halt any further path building and be returned immediately.
352		#[inline]
353	0	pub(crate) fn is_fatal(&self) -> bool {
354	0	matches!(
355	0	self,
356		Self::MaximumSignatureChecksExceeded
357		\| Self::MaximumPathBuildCallsExceeded
358		\| Self::MaximumNameConstraintComparisonsExceeded
359		)
360	0	}
361		}
362
363		impl From<Error> for ControlFlow<Error, Error> {
364	0	fn from(value: Error) -> Self {
365	0	match value {
366		// If an error is fatal, we've exhausted the potential for continued search.
367	0	err if err.is_fatal() => Self::Break(err),
368		// Otherwise we've rejected one candidate chain, but may continue to search for others.
369	0	err => Self::Continue(err),
370		}
371	0	}
372		}
373
374		impl fmt::Display for Error {
375	0	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
376	0	write!(f, "{self:?}")
377	0	}
378		}
379
380		#[cfg(feature = "std")]
381		impl ::std::error::Error for Error {}
382
383		/// Additional context for the `CertNotValidForName` error variant.
384		///
385		/// The contents of this type depend on whether the `alloc` feature is enabled.
386		#[derive(Clone, Debug, PartialEq, Eq)]
387		pub struct InvalidNameContext {
388		/// Expected server name.
389		#[cfg(feature = "alloc")]
390		pub expected: ServerName<'static>,
391		/// The names presented in the end entity certificate.
392		///
393		/// These are the subject names as present in the leaf certificate and may contain DNS names
394		/// with or without a wildcard label as well as IP address names.
395		#[cfg(feature = "alloc")]
396		pub presented: Vec<String>,
397		}
398
399		/// Additional context for the `UnsupportedSignatureAlgorithmForPublicKey` error variant.
400		///
401		/// The contents of this type depend on whether the `alloc` feature is enabled.
402		#[derive(Clone, Debug, PartialEq, Eq)]
403		pub struct UnsupportedSignatureAlgorithmForPublicKeyContext {
404		/// The signature algorithm OID.
405		#[cfg(feature = "alloc")]
406		pub signature_algorithm_id: Vec<u8>,
407		/// The public key algorithm OID.
408		#[cfg(feature = "alloc")]
409		pub public_key_algorithm_id: Vec<u8>,
410		}
411
412		/// Additional context for the `UnsupportedSignatureAlgorithm` error variant.
413		///
414		/// The contents of this type depend on whether the `alloc` feature is enabled.
415		#[derive(Clone, Debug, PartialEq, Eq)]
416		pub struct UnsupportedSignatureAlgorithmContext {
417		/// The signature algorithm OID that was unsupported.
418		#[cfg(feature = "alloc")]
419		pub signature_algorithm_id: Vec<u8>,
420		/// Supported algorithms that were available for signature verification.
421		#[cfg(feature = "alloc")]
422		pub supported_algorithms: Vec<AlgorithmIdentifier>,
423		}
424
425		/// Trailing data was found while parsing DER-encoded input for the named type.
426		#[allow(missing_docs)]
427		#[non_exhaustive]
428		#[derive(Clone, Copy, Debug, Eq, PartialEq)]
429		pub enum DerTypeId {
430		BitString,
431		Bool,
432		Certificate,
433		CertificateExtensions,
434		CertificateTbsCertificate,
435		CertRevocationList,
436		CertRevocationListExtension,
437		CrlDistributionPoint,
438		CommonNameInner,
439		CommonNameOuter,
440		DistributionPointName,
441		Extension,
442		GeneralName,
443		RevocationReason,
444		Signature,
445		SignatureAlgorithm,
446		SignedData,
447		SubjectPublicKeyInfo,
448		Time,
449		TrustAnchorV1,
450		TrustAnchorV1TbsCertificate,
451		U8,
452		RevokedCertificate,
453		RevokedCertificateExtension,
454		RevokedCertEntry,
455		IssuingDistributionPoint,
456		}