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 MarshalPKCS1PublicKey(key *rsa.PublicKey) []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 ParsePKCS1PublicKey(der []byte) (*rsa.PublicKey, error)
- func ParsePKCS8PrivateKey(der []byte) (key interface{}, err error)
- func ParsePKIXPublicKey(derBytes []byte) (pub interface{}, err error)
- type CertPool
- type Certificate
- 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
- type CertificateRequest
- type ConstraintViolationError
- type ExtKeyUsage
- type HostnameError
- type InsecureAlgorithmError
- type InvalidReason
- type KeyUsage
- type PEMCipher
- type PublicKeyAlgorithm
- type SignatureAlgorithm
- type SystemRootsError
- type UnhandledCriticalExtension
- type UnknownAuthorityError
- type VerifyOptions
Constants ¶
This section is empty.
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.
Functions ¶
func CreateCertificate ¶
func CreateCertificate(rand io.Reader, template, parent *Certificate, pub, priv interface{}) (cert []byte, err error)
CreateCertificate creates a new X.509v3 certificate based on a template. The following members of template are used:
- AuthorityKeyId
- BasicConstraintsValid
- CRLDistributionPoints
- DNSNames
- EmailAddresses
- ExcludedDNSDomains
- ExcludedEmailAddresses
- ExcludedIPRanges
- ExcludedURIDomains
- ExtKeyUsage
- ExtraExtensions
- IsCA
- IssuingCertificateURL
- KeyUsage
- MaxPathLen
- MaxPathLenZero
- NotAfter
- NotBefore
- OCSPServer
- PermittedDNSDomains
- PermittedDNSDomainsCritical
- PermittedEmailAddresses
- PermittedIPRanges
- PermittedURIDomains
- PolicyIdentifiers
- SerialNumber
- SignatureAlgorithm
- Subject
- SubjectKeyId
- URIs
- 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:
- SignatureAlgorithm
- Subject
- DNSNames
- EmailAddresses
- IPAddresses
- URIs
- ExtraExtensions
- Attributes (deprecated)
priv is the private key to sign the CSR with, and the corresponding public key will be included in the CSR. It must implement crypto.Signer and its Public() method must return a *rsa.PublicKey or a *ecdsa.PublicKey. (A *rsa.PrivateKey or *ecdsa.PrivateKey satisfies this.)
The returned slice is the certificate request in DER encoding.
func DecryptPEMBlock ¶
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 ¶
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 MarshalPKCS1PublicKey ¶
MarshalPKCS1PublicKey converts an RSA public key to PKCS#1, ASN.1 DER form.
func MarshalPKCS8PrivateKey ¶
MarshalPKCS8PrivateKey converts a private key to PKCS#8 encoded form. The following key types are supported: *rsa.PrivateKey, *ecdsa.PrivateKey. Unsupported key types result in an error.
See RFC 5208.
func MarshalPKIXPublicKey ¶
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 ParsePKCS1PublicKey ¶
ParsePKCS1PublicKey parses a PKCS#1 public key in ASN.1 DER form.
func ParsePKCS8PrivateKey ¶
ParsePKCS8PrivateKey parses an unencrypted, PKCS#8 private key. See RFC 5208.
func ParsePKIXPublicKey ¶
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.
Types ¶
type CertPool ¶
type CertPool struct {
// contains filtered or unexported fields
}
CertPool is a set of certificates.
func SystemCertPool ¶
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 returned by SystemCertPool.
New changes in the system cert pool might not be reflected in subsequent calls.
func (*CertPool) AddCert ¶
func (s *CertPool) AddCert(cert *Certificate)
AddCert adds a certificate to a pool.
func (*CertPool) AppendCertsFromPEM ¶
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.
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. (Note that these values may not be valid // if invalid values were contained within a parsed certificate. For // example, an element of DNSNames may not be a valid DNS domain name.) DNSNames []string EmailAddresses []string IPAddresses []net.IP URIs []*url.URL // Name constraints PermittedDNSDomainsCritical bool // if true then the name constraints are marked critical. PermittedDNSDomains []string ExcludedDNSDomains []string PermittedIPRanges []*net.IPNet ExcludedIPRanges []*net.IPNet PermittedEmailAddresses []string ExcludedEmailAddresses []string PermittedURIDomains []string ExcludedURIDomains []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.
Name constraints in the intermediates will be applied to all names claimed in the chain, not just opts.DNSName. Thus it is invalid for a leaf to claim example.com if an intermediate doesn't permit it, even if example.com is not the name being validated. Note that DirectoryName constraints are not supported.
Extended Key Usage values are enforced down a chain, so an intermediate or root that enumerates EKUs prevents a leaf from asserting an EKU not in that list.
WARNING: this function doesn't do any revocation checking.
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 Detail string }
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 contains the CSR attributes that can parse as // pkix.AttributeTypeAndValueSET. // // Deprecated: use Extensions and ExtraExtensions instead for parsing and // generating the requestedExtensions attribute. Attributes []pkix.AttributeTypeAndValueSET // Extensions contains all requested extensions, in raw form. 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 CSR // marshaled by CreateCertificateRequest. 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 by ParseCertificateRequest, // see Extensions instead. ExtraExtensions []pkix.Extension // Subject Alternate Name values. DNSNames []string EmailAddresses []string IPAddresses []net.IP URIs []*url.URL }
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 ExtKeyUsageMicrosoftCommercialCodeSigning ExtKeyUsageMicrosoftKernelCodeSigning )
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 permit a DNS or // other name (including IP address) in the leaf certificate. 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 // NameConstraintsWithoutSANs results when a leaf certificate doesn't // contain a Subject Alternative Name extension, but a CA certificate // contains name constraints, and the Common Name can be interpreted as // a hostname. // // You can avoid this error by setting the experimental GODEBUG environment // variable to "x509ignoreCN=1", disabling Common Name matching entirely. // This behavior might become the default in the future. NameConstraintsWithoutSANs // UnconstrainedName results when a CA certificate contains permitted // name constraints, but leaf certificate contains a name of an // unsupported or unconstrained type. UnconstrainedName // TooManyConstraints results when the number of comparison operations // needed to check a certificate exceeds the limit set by // VerifyOptions.MaxConstraintComparisions. This limit exists to // prevent pathological certificates can consuming excessive amounts of // CPU time to verify. TooManyConstraints // CANotAuthorizedForExtKeyUsage results when an intermediate or root // certificate does not permit a requested extended key usage. CANotAuthorizedForExtKeyUsage )
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.
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. A leaf // certificate is accepted if it contains any of the listed values. An empty // list means ExtKeyUsageServerAuth. To accept any key usage, include // ExtKeyUsageAny. // // Certificate chains are required to nest these extended key usage values. // (This matches the Windows CryptoAPI behavior, but not the spec.) KeyUsages []ExtKeyUsage // MaxConstraintComparisions is the maximum number of comparisons to // perform when checking a given certificate's name constraints. If // zero, a sensible default is used. This limit prevents pathological // certificates from consuming excessive amounts of CPU time when // validating. MaxConstraintComparisions int }
VerifyOptions contains parameters for Certificate.Verify. It's a structure because other PKIX verification APIs have ended up needing many options.