Portability	unknown
Stability	experimental
Maintainer	Vincent Hanquez <vincent@snarc.org>
Safe Haskell	None

Data.X509.Validation

Description

X.509 Certificate checks and validations routines

Follows RFC5280 / RFC6818

Synopsis

Documentation

type FQHN = String Source

a Fully Qualified Host Name, e.g. www.example.com

data FailedReason Source

Possible reason of certificate and chain failure

Constructors

UnknownCriticalExtension	certificate contains an unknown critical extension
Expired	validity ends before checking time
InFuture	validity starts after checking time
SelfSigned	certificate is self signed
UnknownCA	unknown Certificate Authority (CA)
NotAllowedToSign	certificate is not allowed to sign
NotAnAuthority	not a CA
AuthorityTooDeep	Violation of the optional Basic constraint's path length
NoCommonName	Certificate doesn't have any common name (CN)
InvalidName String	Invalid name in certificate
NameMismatch String	connection name and certificate do not match
InvalidWildcard	invalid wildcard in certificate
LeafKeyUsageNotAllowed	the requested key usage is not compatible with the leaf certificate's key usage
LeafKeyPurposeNotAllowed	the requested key purpose is not compatible with the leaf certificate's extended key usage
LeafNotV3	Only authorized an X509.V3 certificate as leaf certificate.
EmptyChain	empty chain of certificate
InvalidSignature SignatureFailure	signature failed

Instances

Eq FailedReason
Show FailedReason

data SignatureFailure Source

Various failure possible during signature checking

Constructors

SignatureInvalid	signature doesn't verify
SignaturePubkeyMismatch	algorithm and public key mismatch, cannot proceed
SignatureUnimplemented	unimplemented signature algorithm

Instances

Eq SignatureFailure
Show SignatureFailure

data Parameters Source

Validation parameters. List all the conditions where/when we want the certificate checks to happen.

Constructors

Parameters
Fields parameterTime :: UTCTime the time when we want the certificate check to happen. usually should be the time as of now. parameterFQHN :: FQHN fqhn to match

Instances

Eq Parameters
Show Parameters

data Checks Source

A set of checks to activate or parametrize to perform on certificates.

It's recommended to use defaultChecks to create the structure, to better cope with future changes or expansion of the structure.

Constructors

Checks

Fields

checkTimeValidity :: Bool: check time validity of every certificate in the chain. the make sure that current time is between each validity bounds in the certificate
checkStrictOrdering :: Bool: Check that no certificate is included that shouldn't be included. unfortunately despite the specification violation, a lots of real world server serves useless and usually old certificates that are not relevant to the certificate sent, in their chain.
checkCAConstraints :: Bool: Check that signing certificate got the CA basic constraint. this is absolutely not recommended to turn it off.
checkExhaustive :: Bool: Check the whole certificate chain without stopping at the first failure. Allow gathering a exhaustive list of failure reasons. if this is turn off, it's absolutely not safe to ignore a failed reason even it doesn't look serious (e.g. Expired) as other more serious checks would not have been performed.
checkLeafV3 :: Bool: Check that the leaf certificate is version 3. If disable, version 2 certificate is authorized in leaf position and key usage cannot be checked.
checkLeafKeyUsage :: [ExtKeyUsageFlag]: Check that the leaf certificate is authorized to be used for certain usage. If set to empty list no check are performed, otherwise all the flags is the list need to exists in the key usage extension. If the extension is not present, the check will pass and behave as if the certificate key is not restricted to any specific usage.
checkLeafKeyPurpose :: [ExtKeyUsagePurpose]: Check that the leaf certificate is authorized to be used for certain purpose. If set to empty list no check are performed, otherwise all the flags is the list need to exists in the extended key usage extension if present. If the extension is not present, then the check will pass and behave as if the certificate is not restricted to any specific purpose.
checkFQHN :: Bool: Check the top certificate names matching the fully qualified hostname (FQHN). it's not recommended to turn this check off, if no other name checks are performed.

Instances

Eq Checks
Show Checks

data Hooks Source

A set of hooks to manipulate the way the verification works.

BEWARE, it's easy to change behavior leading to compromised security.

Constructors

Hooks

Fields

hookMatchSubjectIssuer :: DistinguishedName -> Certificate -> Bool: check the the issuer DistinguishedName match the subject DistinguishedName of a certificate.
hookValidateTime :: UTCTime -> Certificate -> [FailedReason]: validate that the parametrized time valide with the certificate in argument
hookValidateName :: FQHN -> Certificate -> [FailedReason]: validate the certificate leaf name with the DNS named used to connect

defaultChecks :: Checks Source

Default checks to perform

The default checks are: * Each certificate time is valid * CA constraints is enforced for signing certificate * Leaf certificate is X.509 v3 * Check that the FQHN match

defaultHooks :: Hooks Source

Default hooks in the validation process

validate :: Hooks -> Checks -> CertificateStore -> FQHN -> CertificateChain -> IO [FailedReason]Source

validate a certificate chain.

validateWith :: Parameters -> Hooks -> Checks -> CertificateStore -> CertificateChain -> IO [FailedReason]Source

Validate a certificate chain with explicit parameters

getFingerprint Source

Arguments

:: (Show a, Eq a, ASN1Object a)
=> SignedExact a	object to fingerprint
-> HashALG	algorithm to compute the fingerprint
-> ByteString	fingerprint in binary form

Get the fingerprint of the whole signed object using the hashing algorithm specified