Package x509

import "crypto/x509"
Overview
Index
Examples
Documentation

Overview

Package x509 parses X.509-encoded keys and certificates.

On UNIX systems the environment variables SSL_CERT_FILE and SSL_CERT_DIR can be used to override the system default locations for the SSL certificate file and SSL certificate files directory, respectively.

Index

Variables
func CreateCertificate(rand io.Reader, template, parent *Certificate, pub, priv interface{}) (cert []byte, err error)
func CreateCertificateRequest(rand io.Reader, template *CertificateRequest, priv interface{}) (csr []byte, err error)
func DecryptPEMBlock(b *pem.Block, password []byte) ([]byte, error)
func EncryptPEMBlock(rand io.Reader, blockType string, data, password []byte, alg PEMCipher) (*pem.Block, error)
func IsEncryptedPEMBlock(b *pem.Block) bool
func MarshalECPrivateKey(key *ecdsa.PrivateKey) ([]byte, error)
func MarshalPKCS1PrivateKey(key *rsa.PrivateKey) []byte
func MarshalPKCS8PrivateKey(key interface{}) ([]byte, error)
func MarshalPKIXPublicKey(pub interface{}) ([]byte, error)
func ParseCRL(crlBytes []byte) (*pkix.CertificateList, error)
func ParseDERCRL(derBytes []byte) (*pkix.CertificateList, error)
func ParseECPrivateKey(der []byte) (*ecdsa.PrivateKey, error)
func ParsePKCS1PrivateKey(der []byte) (*rsa.PrivateKey, error)
func ParsePKCS8PrivateKey(der []byte) (key interface{}, err error)
func ParsePKIXPublicKey(derBytes []byte) (pub interface{}, err error)
type CertPool
func NewCertPool() *CertPool
func SystemCertPool() (*CertPool, error)
func (s *CertPool) AddCert(cert *Certificate)
func (s *CertPool) AppendCertsFromPEM(pemCerts []byte) (ok bool)
func (s *CertPool) Subjects() [][]byte
type Certificate
func ParseCertificate(asn1Data []byte) (*Certificate, error)
func ParseCertificates(asn1Data []byte) ([]*Certificate, error)
func (c *Certificate) CheckCRLSignature(crl *pkix.CertificateList) error
func (c *Certificate) CheckSignature(algo SignatureAlgorithm, signed, signature []byte) error
func (c *Certificate) CheckSignatureFrom(parent *Certificate) error
func (c *Certificate) CreateCRL(rand io.Reader, priv interface{}, revokedCerts []pkix.RevokedCertificate, ...) (crlBytes []byte, err error)
func (c *Certificate) Equal(other *Certificate) bool
func (c *Certificate) Verify(opts VerifyOptions) (chains [][]*Certificate, err error)
func (c *Certificate) VerifyHostname(h string) error
type CertificateInvalidError
func (e CertificateInvalidError) Error() string
type CertificateRequest
func ParseCertificateRequest(asn1Data []byte) (*CertificateRequest, error)
func (c *CertificateRequest) CheckSignature() error
type ConstraintViolationError
func (ConstraintViolationError) Error() string
type ExtKeyUsage
type HostnameError
func (h HostnameError) Error() string
type InsecureAlgorithmError
func (e InsecureAlgorithmError) Error() string
type InvalidReason
type KeyUsage
type PEMCipher
type PublicKeyAlgorithm
func (algo PublicKeyAlgorithm) String() string
type SignatureAlgorithm
func (algo SignatureAlgorithm) String() string
type SystemRootsError
func (se SystemRootsError) Error() string
type UnhandledCriticalExtension
func (h UnhandledCriticalExtension) Error() string
type UnknownAuthorityError
func (e UnknownAuthorityError) Error() string
type VerifyOptions

Examples

Certificate.Verify
ParsePKIXPublicKey

Documentation

Variables

var ErrUnsupportedAlgorithm = errors.New("x509: cannot verify signature: algorithm unimplemented")

ErrUnsupportedAlgorithm results from attempting to perform an operation that involves algorithms that are not currently implemented.

var IncorrectPasswordError = errors.New("x509: decryption password incorrect")

IncorrectPasswordError is returned when an incorrect password is detected.

func CreateCertificate

func CreateCertificate(rand io.Reader, template, parent *Certificate, pub, priv interface{}) (cert []byte, err error)

CreateCertificate creates a new certificate based on a template. The following members of template are used: AuthorityKeyId, BasicConstraintsValid, DNSNames, ExcludedDNSDomains, ExtKeyUsage, IsCA, KeyUsage, MaxPathLen, MaxPathLenZero, NotAfter, NotBefore, PermittedDNSDomains, PermittedDNSDomainsCritical, SerialNumber, SignatureAlgorithm, Subject, SubjectKeyId, and UnknownExtKeyUsage.

The certificate is signed by parent. If parent is equal to template then the certificate is self-signed. The parameter pub is the public key of the signee and priv is the private key of the signer.

The returned slice is the certificate in DER encoding.

All keys types that are implemented via crypto.Signer are supported (This includes *rsa.PublicKey and *ecdsa.PublicKey.)

The AuthorityKeyId will be taken from the SubjectKeyId of parent, if any, unless the resulting certificate is self-signed. Otherwise the value from template will be used.

func CreateCertificateRequest

func CreateCertificateRequest(rand io.Reader, template *CertificateRequest, priv interface{}) (csr []byte, err error)

CreateCertificateRequest creates a new certificate request based on a template. The following members of template are used: Attributes, DNSNames, EmailAddresses, ExtraExtensions, IPAddresses, SignatureAlgorithm, and Subject. The private key is the private key of the signer.

The returned slice is the certificate request in DER encoding.

All keys types that are implemented via crypto.Signer are supported (This includes *rsa.PublicKey and *ecdsa.PublicKey.)

func DecryptPEMBlock

func DecryptPEMBlock(b *pem.Block, password []byte) ([]byte, error)

DecryptPEMBlock takes a password encrypted PEM block and the password used to encrypt it and returns a slice of decrypted DER encoded bytes. It inspects the DEK-Info header to determine the algorithm used for decryption. If no DEK-Info header is present, an error is returned. If an incorrect password is detected an IncorrectPasswordError is returned. Because of deficiencies in the encrypted-PEM format, it's not always possible to detect an incorrect password. In these cases no error will be returned but the decrypted DER bytes will be random noise.

func EncryptPEMBlock

func EncryptPEMBlock(rand io.Reader, blockType string, data, password []byte, alg PEMCipher) (*pem.Block, error)

EncryptPEMBlock returns a PEM block of the specified type holding the given DER-encoded data encrypted with the specified algorithm and password.

func IsEncryptedPEMBlock

func IsEncryptedPEMBlock(b *pem.Block) bool

IsEncryptedPEMBlock returns if the PEM block is password encrypted.

func MarshalECPrivateKey

func MarshalECPrivateKey(key *ecdsa.PrivateKey) ([]byte, error)

MarshalECPrivateKey marshals an EC private key into ASN.1, DER format.

func MarshalPKCS1PrivateKey

func MarshalPKCS1PrivateKey(key *rsa.PrivateKey) []byte

MarshalPKCS1PrivateKey converts a private key to ASN.1 DER encoded form.

func MarshalPKCS8PrivateKey

func MarshalPKCS8PrivateKey(key interface{}) ([]byte, error)

MarshalPKCS8PrivateKey converts a private key to PKCS#8 encoded form. The following key types are supported: *rsa.PrivateKey, *ecdsa.PublicKey. Unsupported key types result in an error.

See RFC 5208.

func MarshalPKIXPublicKey

func MarshalPKIXPublicKey(pub interface{}) ([]byte, error)

MarshalPKIXPublicKey serialises a public key to DER-encoded PKIX format.

func ParseCRL

func ParseCRL(crlBytes []byte) (*pkix.CertificateList, error)

ParseCRL parses a CRL from the given bytes. It's often the case that PEM encoded CRLs will appear where they should be DER encoded, so this function will transparently handle PEM encoding as long as there isn't any leading garbage.

func ParseDERCRL

func ParseDERCRL(derBytes []byte) (*pkix.CertificateList, error)

ParseDERCRL parses a DER encoded CRL from the given bytes.

func ParseECPrivateKey

func ParseECPrivateKey(der []byte) (*ecdsa.PrivateKey, error)

ParseECPrivateKey parses an ASN.1 Elliptic Curve Private Key Structure.

func ParsePKCS1PrivateKey

func ParsePKCS1PrivateKey(der []byte) (*rsa.PrivateKey, error)

ParsePKCS1PrivateKey returns an RSA private key from its ASN.1 PKCS#1 DER encoded form.

func ParsePKCS8PrivateKey

func ParsePKCS8PrivateKey(der []byte) (key interface{}, err error)

ParsePKCS8PrivateKey parses an unencrypted, PKCS#8 private key. See RFC 5208.

func ParsePKIXPublicKey

func ParsePKIXPublicKey(derBytes []byte) (pub interface{}, err error)

ParsePKIXPublicKey parses a DER encoded public key. These values are typically found in PEM blocks with "BEGIN PUBLIC KEY".

Supported key types include RSA, DSA, and ECDSA. Unknown key types result in an error.

On success, pub will be of type *rsa.PublicKey, *dsa.PublicKey, or *ecdsa.PublicKey.

Code:

const pubPEM = `
-----BEGIN PUBLIC KEY-----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-----END PUBLIC KEY-----`

block, _ := pem.Decode([]byte(pubPEM))
if block == nil {
    panic("failed to parse PEM block containing the public key")
}

pub, err := x509.ParsePKIXPublicKey(block.Bytes)
if err != nil {
    panic("failed to parse DER encoded public key: " + err.Error())
}

switch pub := pub.(type) {
case *rsa.PublicKey:
    fmt.Println("pub is of type RSA:", pub)
case *dsa.PublicKey:
    fmt.Println("pub is of type DSA:", pub)
case *ecdsa.PublicKey:
    fmt.Println("pub is of type ECDSA:", pub)
default:
    panic("unknown type of public key")
}

type CertPool

type CertPool struct {
    // contains filtered or unexported fields
}

CertPool is a set of certificates.

func NewCertPool

func NewCertPool() *CertPool

NewCertPool returns a new, empty CertPool.

func SystemCertPool

func SystemCertPool() (*CertPool, error)

SystemCertPool returns a copy of the system cert pool.

Any mutations to the returned pool are not written to disk and do not affect any other pool.

func CertPool.AddCert

func (s *CertPool) AddCert(cert *Certificate)

AddCert adds a certificate to a pool.

func CertPool.AppendCertsFromPEM

func (s *CertPool) AppendCertsFromPEM(pemCerts []byte) (ok bool)

AppendCertsFromPEM attempts to parse a series of PEM encoded certificates. It appends any certificates found to s and reports whether any certificates were successfully parsed.

On many Linux systems, /etc/ssl/cert.pem will contain the system wide set of root CAs in a format suitable for this function.

func CertPool.Subjects

func (s *CertPool) Subjects() [][]byte

Subjects returns a list of the DER-encoded subjects of all of the certificates in the pool.

type Certificate

type Certificate struct {
    Raw                     []byte // Complete ASN.1 DER content (certificate, signature algorithm and signature).
    RawTBSCertificate       []byte // Certificate part of raw ASN.1 DER content.
    RawSubjectPublicKeyInfo []byte // DER encoded SubjectPublicKeyInfo.
    RawSubject              []byte // DER encoded Subject
    RawIssuer               []byte // DER encoded Issuer

    Signature          []byte
    SignatureAlgorithm SignatureAlgorithm

    PublicKeyAlgorithm PublicKeyAlgorithm
    PublicKey          interface{}

    Version             int
    SerialNumber        *big.Int
    Issuer              pkix.Name
    Subject             pkix.Name
    NotBefore, NotAfter time.Time // Validity bounds.
    KeyUsage            KeyUsage

    // Extensions contains raw X.509 extensions. When parsing certificates,
    // this can be used to extract non-critical extensions that are not
    // parsed by this package. When marshaling certificates, the Extensions
    // field is ignored, see ExtraExtensions.
    Extensions []pkix.Extension

    // ExtraExtensions contains extensions to be copied, raw, into any
    // marshaled certificates. Values override any extensions that would
    // otherwise be produced based on the other fields. The ExtraExtensions
    // field is not populated when parsing certificates, see Extensions.
    ExtraExtensions []pkix.Extension

    // UnhandledCriticalExtensions contains a list of extension IDs that
    // were not (fully) processed when parsing. Verify will fail if this
    // slice is non-empty, unless verification is delegated to an OS
    // library which understands all the critical extensions.
    //
    // Users can access these extensions using Extensions and can remove
    // elements from this slice if they believe that they have been
    // handled.
    UnhandledCriticalExtensions []asn1.ObjectIdentifier

    ExtKeyUsage        []ExtKeyUsage           // Sequence of extended key usages.
    UnknownExtKeyUsage []asn1.ObjectIdentifier // Encountered extended key usages unknown to this package.

    // BasicConstraintsValid indicates whether IsCA, MaxPathLen,
    // and MaxPathLenZero are valid.
    BasicConstraintsValid bool
    IsCA                  bool

    // MaxPathLen and MaxPathLenZero indicate the presence and
    // value of the BasicConstraints' "pathLenConstraint".
    //
    // When parsing a certificate, a positive non-zero MaxPathLen
    // means that the field was specified, -1 means it was unset,
    // and MaxPathLenZero being true mean that the field was
    // explicitly set to zero. The case of MaxPathLen==0 with MaxPathLenZero==false
    // should be treated equivalent to -1 (unset).
    //
    // When generating a certificate, an unset pathLenConstraint
    // can be requested with either MaxPathLen == -1 or using the
    // zero value for both MaxPathLen and MaxPathLenZero.
    MaxPathLen int
    // MaxPathLenZero indicates that BasicConstraintsValid==true
    // and MaxPathLen==0 should be interpreted as an actual
    // maximum path length of zero. Otherwise, that combination is
    // interpreted as MaxPathLen not being set.
    MaxPathLenZero bool

    SubjectKeyId   []byte
    AuthorityKeyId []byte

    // RFC 5280, 4.2.2.1 (Authority Information Access)
    OCSPServer            []string
    IssuingCertificateURL []string

    // Subject Alternate Name values
    DNSNames       []string
    EmailAddresses []string
    IPAddresses    []net.IP

    // Name constraints
    PermittedDNSDomainsCritical bool // if true then the name constraints are marked critical.
    PermittedDNSDomains         []string
    ExcludedDNSDomains          []string

    // CRL Distribution Points
    CRLDistributionPoints []string

    PolicyIdentifiers []asn1.ObjectIdentifier
}

A Certificate represents an X.509 certificate.

func ParseCertificate

func ParseCertificate(asn1Data []byte) (*Certificate, error)

ParseCertificate parses a single certificate from the given ASN.1 DER data.

func ParseCertificates

func ParseCertificates(asn1Data []byte) ([]*Certificate, error)

ParseCertificates parses one or more certificates from the given ASN.1 DER data. The certificates must be concatenated with no intermediate padding.

func Certificate.CheckCRLSignature

func (c *Certificate) CheckCRLSignature(crl *pkix.CertificateList) error

CheckCRLSignature checks that the signature in crl is from c.

func Certificate.CheckSignature

func (c *Certificate) CheckSignature(algo SignatureAlgorithm, signed, signature []byte) error

CheckSignature verifies that signature is a valid signature over signed from c's public key.

func Certificate.CheckSignatureFrom

func (c *Certificate) CheckSignatureFrom(parent *Certificate) error

CheckSignatureFrom verifies that the signature on c is a valid signature from parent.

func Certificate.CreateCRL

func (c *Certificate) CreateCRL(rand io.Reader, priv interface{}, revokedCerts []pkix.RevokedCertificate, now, expiry time.Time) (crlBytes []byte, err error)

CreateCRL returns a DER encoded CRL, signed by this Certificate, that contains the given list of revoked certificates.

func Certificate.Equal

func (c *Certificate) Equal(other *Certificate) bool

func Certificate.Verify

func (c *Certificate) Verify(opts VerifyOptions) (chains [][]*Certificate, err error)

Verify attempts to verify c by building one or more chains from c to a certificate in opts.Roots, using certificates in opts.Intermediates if needed. If successful, it returns one or more chains where the first element of the chain is c and the last element is from opts.Roots.

If opts.Roots is nil and system roots are unavailable the returned error will be of type SystemRootsError.

WARNING: this doesn't do any revocation checking.

Code:

// Verifying with a custom list of root certificates.

const rootPEM = `
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----`

const certPEM = `
-----BEGIN CERTIFICATE-----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==
-----END CERTIFICATE-----`

// First, create the set of root certificates. For this example we only
// have one. It's also possible to omit this in order to use the
// default root set of the current operating system.
roots := x509.NewCertPool()
ok := roots.AppendCertsFromPEM([]byte(rootPEM))
if !ok {
    panic("failed to parse root certificate")
}

block, _ := pem.Decode([]byte(certPEM))
if block == nil {
    panic("failed to parse certificate PEM")
}
cert, err := x509.ParseCertificate(block.Bytes)
if err != nil {
    panic("failed to parse certificate: " + err.Error())
}

opts := x509.VerifyOptions{
    DNSName: "mail.google.com",
    Roots:   roots,
}

if _, err := cert.Verify(opts); err != nil {
    panic("failed to verify certificate: " + err.Error())
}

func Certificate.VerifyHostname

func (c *Certificate) VerifyHostname(h string) error

VerifyHostname returns nil if c is a valid certificate for the named host. Otherwise it returns an error describing the mismatch.

type CertificateInvalidError

type CertificateInvalidError struct {
    Cert   *Certificate
    Reason InvalidReason
}

CertificateInvalidError results when an odd error occurs. Users of this library probably want to handle all these errors uniformly.

func CertificateInvalidError.Error

func (e CertificateInvalidError) Error() string

type CertificateRequest

type CertificateRequest struct {
    Raw                      []byte // Complete ASN.1 DER content (CSR, signature algorithm and signature).
    RawTBSCertificateRequest []byte // Certificate request info part of raw ASN.1 DER content.
    RawSubjectPublicKeyInfo  []byte // DER encoded SubjectPublicKeyInfo.
    RawSubject               []byte // DER encoded Subject.

    Version            int
    Signature          []byte
    SignatureAlgorithm SignatureAlgorithm

    PublicKeyAlgorithm PublicKeyAlgorithm
    PublicKey          interface{}

    Subject pkix.Name

    // Attributes is the dried husk of a bug and shouldn't be used.
    Attributes []pkix.AttributeTypeAndValueSET

    // Extensions contains raw X.509 extensions. When parsing CSRs, this
    // can be used to extract extensions that are not parsed by this
    // package.
    Extensions []pkix.Extension

    // ExtraExtensions contains extensions to be copied, raw, into any
    // marshaled CSR. Values override any extensions that would otherwise
    // be produced based on the other fields but are overridden by any
    // extensions specified in Attributes.
    //
    // The ExtraExtensions field is not populated when parsing CSRs, see
    // Extensions.
    ExtraExtensions []pkix.Extension

    // Subject Alternate Name values.
    DNSNames       []string
    EmailAddresses []string
    IPAddresses    []net.IP
}

CertificateRequest represents a PKCS #10, certificate signature request.

func ParseCertificateRequest

func ParseCertificateRequest(asn1Data []byte) (*CertificateRequest, error)

ParseCertificateRequest parses a single certificate request from the given ASN.1 DER data.

func CertificateRequest.CheckSignature

func (c *CertificateRequest) CheckSignature() error

CheckSignature reports whether the signature on c is valid.

type ConstraintViolationError

type ConstraintViolationError struct{}

ConstraintViolationError results when a requested usage is not permitted by a certificate. For example: checking a signature when the public key isn't a certificate signing key.

func ConstraintViolationError.Error

func (ConstraintViolationError) Error() string

type ExtKeyUsage

type ExtKeyUsage int

ExtKeyUsage represents an extended set of actions that are valid for a given key. Each of the ExtKeyUsage* constants define a unique action.

const (
    ExtKeyUsageAny ExtKeyUsage = iota
    ExtKeyUsageServerAuth
    ExtKeyUsageClientAuth
    ExtKeyUsageCodeSigning
    ExtKeyUsageEmailProtection
    ExtKeyUsageIPSECEndSystem
    ExtKeyUsageIPSECTunnel
    ExtKeyUsageIPSECUser
    ExtKeyUsageTimeStamping
    ExtKeyUsageOCSPSigning
    ExtKeyUsageMicrosoftServerGatedCrypto
    ExtKeyUsageNetscapeServerGatedCrypto
)

type HostnameError

type HostnameError struct {
    Certificate *Certificate
    Host        string
}

HostnameError results when the set of authorized names doesn't match the requested name.

func HostnameError.Error

func (h HostnameError) Error() string

type InsecureAlgorithmError

type InsecureAlgorithmError SignatureAlgorithm

An InsecureAlgorithmError

func InsecureAlgorithmError.Error

func (e InsecureAlgorithmError) Error() string

type InvalidReason

type InvalidReason int
const (
    // NotAuthorizedToSign results when a certificate is signed by another
    // which isn't marked as a CA certificate.
    NotAuthorizedToSign InvalidReason = iota
    // Expired results when a certificate has expired, based on the time
    // given in the VerifyOptions.
    Expired
    // CANotAuthorizedForThisName results when an intermediate or root
    // certificate has a name constraint which doesn't include the name
    // being checked.
    CANotAuthorizedForThisName
    // TooManyIntermediates results when a path length constraint is
    // violated.
    TooManyIntermediates
    // IncompatibleUsage results when the certificate's key usage indicates
    // that it may only be used for a different purpose.
    IncompatibleUsage
    // NameMismatch results when the subject name of a parent certificate
    // does not match the issuer name in the child.
    NameMismatch
)

type KeyUsage

type KeyUsage int

KeyUsage represents the set of actions that are valid for a given key. It's a bitmap of the KeyUsage* constants.

const (
    KeyUsageDigitalSignature KeyUsage = 1 << iota
    KeyUsageContentCommitment
    KeyUsageKeyEncipherment
    KeyUsageDataEncipherment
    KeyUsageKeyAgreement
    KeyUsageCertSign
    KeyUsageCRLSign
    KeyUsageEncipherOnly
    KeyUsageDecipherOnly
)

type PEMCipher

type PEMCipher int
const (
    PEMCipherDES PEMCipher
    PEMCipher3DES
    PEMCipherAES128
    PEMCipherAES192
    PEMCipherAES256
)

Possible values for the EncryptPEMBlock encryption algorithm.

type PublicKeyAlgorithm

type PublicKeyAlgorithm int
const (
    UnknownPublicKeyAlgorithm PublicKeyAlgorithm = iota
    RSA
    DSA
    ECDSA
)

func PublicKeyAlgorithm.String

func (algo PublicKeyAlgorithm) String() string

type SignatureAlgorithm

type SignatureAlgorithm int
const (
    UnknownSignatureAlgorithm SignatureAlgorithm = iota
    MD2WithRSA
    MD5WithRSA
    SHA1WithRSA
    SHA256WithRSA
    SHA384WithRSA
    SHA512WithRSA
    DSAWithSHA1
    DSAWithSHA256
    ECDSAWithSHA1
    ECDSAWithSHA256
    ECDSAWithSHA384
    ECDSAWithSHA512
    SHA256WithRSAPSS
    SHA384WithRSAPSS
    SHA512WithRSAPSS
)

func SignatureAlgorithm.String

func (algo SignatureAlgorithm) String() string

type SystemRootsError

type SystemRootsError struct {
    Err error
}

SystemRootsError results when we fail to load the system root certificates.

func SystemRootsError.Error

func (se SystemRootsError) Error() string

type UnhandledCriticalExtension

type UnhandledCriticalExtension struct{}

func UnhandledCriticalExtension.Error

func (h UnhandledCriticalExtension) Error() string

type UnknownAuthorityError

type UnknownAuthorityError struct {
    Cert *Certificate
    // contains filtered or unexported fields
}

UnknownAuthorityError results when the certificate issuer is unknown

func UnknownAuthorityError.Error

func (e UnknownAuthorityError) Error() string

type VerifyOptions

type VerifyOptions struct {
    DNSName       string
    Intermediates *CertPool
    Roots         *CertPool // if nil, the system roots are used
    CurrentTime   time.Time // if zero, the current time is used
    // KeyUsage specifies which Extended Key Usage values are acceptable.
    // An empty list means ExtKeyUsageServerAuth. Key usage is considered a
    // constraint down the chain which mirrors Windows CryptoAPI behavior,
    // but not the spec. To accept any key usage, include ExtKeyUsageAny.
    KeyUsages []ExtKeyUsage
}

VerifyOptions contains parameters for Certificate.Verify. It's a structure because other PKIX verification APIs have ended up needing many options.