| // 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. |
| |
| use core::fmt; |
| use core::ops::ControlFlow; |
| |
| /// An error that occurs during certificate validation or name validation. |
| #[derive(Clone, Copy, 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 certificate is not valid for the name it is being validated for. |
| CertNotValidForName, |
| |
| /// 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| /// The certificate, or one of its issuers, has been revoked. |
| CertRevoked, |
| |
| /// 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. |
| RequiredEkuNotFound, |
| |
| /// The algorithm in the TBSCertificate "signature" field of a certificate |
| /// does not match the algorithm in the signature of the certificate. |
| SignatureAlgorithmMismatch, |
| |
| /// A valid issuer for the certificate could not be found. |
| UnknownIssuer, |
| |
| /// 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 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 revocation reason is not in the set of supported revocation reasons. |
| UnsupportedRevocationReason, |
| |
| /// The signature algorithm for a signature over a CRL is not in the set of supported |
| /// signature algorithms given. |
| UnsupportedCrlSignatureAlgorithm, |
| |
| /// The signature algorithm for a signature is not in the set of supported |
| /// signature algorithms given. |
| UnsupportedSignatureAlgorithm, |
| |
| /// 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). |
| 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). |
| UnsupportedSignatureAlgorithmForPublicKey, |
| } |
| |
| 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: Error) -> Error { |
| // 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 |
| Error::CertNotValidYet | Error::CertExpired => 290, |
| Error::CertNotValidForName => 280, |
| Error::CertRevoked => 270, |
| Error::InvalidCrlSignatureForPublicKey | Error::InvalidSignatureForPublicKey => 260, |
| Error::SignatureAlgorithmMismatch => 250, |
| Error::RequiredEkuNotFound => 240, |
| Error::NameConstraintViolation => 230, |
| Error::PathLenConstraintViolated => 220, |
| Error::CaUsedAsEndEntity | Error::EndEntityUsedAsCa => 210, |
| Error::IssuerNotCrlSigner => 200, |
| |
| // Errors related to supported features used in an invalid way. |
| Error::InvalidCertValidity => 190, |
| Error::InvalidNetworkMaskConstraint => 180, |
| Error::InvalidSerialNumber => 170, |
| Error::InvalidCrlNumber => 160, |
| |
| // Errors related to unsupported features. |
| Error::UnsupportedCrlSignatureAlgorithmForPublicKey |
| | Error::UnsupportedSignatureAlgorithmForPublicKey => 150, |
| Error::UnsupportedCrlSignatureAlgorithm | Error::UnsupportedSignatureAlgorithm => 140, |
| Error::UnsupportedCriticalExtension => 130, |
| Error::UnsupportedCertVersion => 130, |
| Error::UnsupportedCrlVersion => 120, |
| Error::UnsupportedDeltaCrl => 110, |
| Error::UnsupportedIndirectCrl => 100, |
| Error::UnsupportedRevocationReason => 90, |
| // Reserved for webpki 0.102.0+ usages: |
| // Error::UnsupportedRevocationReasonsPartitioning => 80, |
| // Error::UnsupportedCrlIssuingDistributionPoint => 70, |
| Error::MaximumPathDepthExceeded => 61, |
| |
| // Errors related to malformed data. |
| Error::MalformedDnsIdentifier => 60, |
| Error::MalformedNameConstraint => 50, |
| Error::MalformedExtensions => 40, |
| Error::ExtensionValueInvalid => 30, |
| |
| // Generic DER errors. |
| Error::BadDerTime => 20, |
| Error::BadDer => 10, |
| |
| // Special case errors - not subject to ranking. |
| Error::MaximumSignatureChecksExceeded => 0, |
| Error::MaximumPathBuildCallsExceeded => 0, |
| Error::MaximumNameConstraintComparisonsExceeded => 0, |
| |
| // Default catch all error - should be renamed in the future. |
| Error::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, |
| Error::MaximumSignatureChecksExceeded |
| | Error::MaximumPathBuildCallsExceeded |
| | Error::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")] |
| #[cfg_attr(docsrs, doc(cfg(feature = "std")))] |
| impl ::std::error::Error for Error {} |
| |
| impl From<untrusted::EndOfInput> for Error { |
| fn from(_: untrusted::EndOfInput) -> Self { |
| Error::BadDer |
| } |
| } |