local-server/vendor/github.com/cloudflare/cfssl/helpers/helpers.go
2018-12-11 00:44:05 +11:00

591 lines
17 KiB
Go

// Package helpers implements utility functionality common to many
// CFSSL packages.
package helpers
import (
"bytes"
"crypto"
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rsa"
"crypto/tls"
"crypto/x509"
"crypto/x509/pkix"
"encoding/asn1"
"encoding/pem"
"errors"
"fmt"
"io/ioutil"
"os"
"github.com/google/certificate-transparency-go"
cttls "github.com/google/certificate-transparency-go/tls"
ctx509 "github.com/google/certificate-transparency-go/x509"
"golang.org/x/crypto/ocsp"
"strings"
"time"
"github.com/cloudflare/cfssl/crypto/pkcs7"
cferr "github.com/cloudflare/cfssl/errors"
"github.com/cloudflare/cfssl/helpers/derhelpers"
"github.com/cloudflare/cfssl/log"
"golang.org/x/crypto/pkcs12"
)
// OneYear is a time.Duration representing a year's worth of seconds.
const OneYear = 8760 * time.Hour
// OneDay is a time.Duration representing a day's worth of seconds.
const OneDay = 24 * time.Hour
// InclusiveDate returns the time.Time representation of a date - 1
// nanosecond. This allows time.After to be used inclusively.
func InclusiveDate(year int, month time.Month, day int) time.Time {
return time.Date(year, month, day, 0, 0, 0, 0, time.UTC).Add(-1 * time.Nanosecond)
}
// Jul2012 is the July 2012 CAB Forum deadline for when CAs must stop
// issuing certificates valid for more than 5 years.
var Jul2012 = InclusiveDate(2012, time.July, 01)
// Apr2015 is the April 2015 CAB Forum deadline for when CAs must stop
// issuing certificates valid for more than 39 months.
var Apr2015 = InclusiveDate(2015, time.April, 01)
// KeyLength returns the bit size of ECDSA or RSA PublicKey
func KeyLength(key interface{}) int {
if key == nil {
return 0
}
if ecdsaKey, ok := key.(*ecdsa.PublicKey); ok {
return ecdsaKey.Curve.Params().BitSize
} else if rsaKey, ok := key.(*rsa.PublicKey); ok {
return rsaKey.N.BitLen()
}
return 0
}
// ExpiryTime returns the time when the certificate chain is expired.
func ExpiryTime(chain []*x509.Certificate) (notAfter time.Time) {
if len(chain) == 0 {
return
}
notAfter = chain[0].NotAfter
for _, cert := range chain {
if notAfter.After(cert.NotAfter) {
notAfter = cert.NotAfter
}
}
return
}
// MonthsValid returns the number of months for which a certificate is valid.
func MonthsValid(c *x509.Certificate) int {
issued := c.NotBefore
expiry := c.NotAfter
years := (expiry.Year() - issued.Year())
months := years*12 + int(expiry.Month()) - int(issued.Month())
// Round up if valid for less than a full month
if expiry.Day() > issued.Day() {
months++
}
return months
}
// ValidExpiry determines if a certificate is valid for an acceptable
// length of time per the CA/Browser Forum baseline requirements.
// See https://cabforum.org/wp-content/uploads/CAB-Forum-BR-1.3.0.pdf
func ValidExpiry(c *x509.Certificate) bool {
issued := c.NotBefore
var maxMonths int
switch {
case issued.After(Apr2015):
maxMonths = 39
case issued.After(Jul2012):
maxMonths = 60
case issued.Before(Jul2012):
maxMonths = 120
}
if MonthsValid(c) > maxMonths {
return false
}
return true
}
// SignatureString returns the TLS signature string corresponding to
// an X509 signature algorithm.
func SignatureString(alg x509.SignatureAlgorithm) string {
switch alg {
case x509.MD2WithRSA:
return "MD2WithRSA"
case x509.MD5WithRSA:
return "MD5WithRSA"
case x509.SHA1WithRSA:
return "SHA1WithRSA"
case x509.SHA256WithRSA:
return "SHA256WithRSA"
case x509.SHA384WithRSA:
return "SHA384WithRSA"
case x509.SHA512WithRSA:
return "SHA512WithRSA"
case x509.DSAWithSHA1:
return "DSAWithSHA1"
case x509.DSAWithSHA256:
return "DSAWithSHA256"
case x509.ECDSAWithSHA1:
return "ECDSAWithSHA1"
case x509.ECDSAWithSHA256:
return "ECDSAWithSHA256"
case x509.ECDSAWithSHA384:
return "ECDSAWithSHA384"
case x509.ECDSAWithSHA512:
return "ECDSAWithSHA512"
default:
return "Unknown Signature"
}
}
// HashAlgoString returns the hash algorithm name contains in the signature
// method.
func HashAlgoString(alg x509.SignatureAlgorithm) string {
switch alg {
case x509.MD2WithRSA:
return "MD2"
case x509.MD5WithRSA:
return "MD5"
case x509.SHA1WithRSA:
return "SHA1"
case x509.SHA256WithRSA:
return "SHA256"
case x509.SHA384WithRSA:
return "SHA384"
case x509.SHA512WithRSA:
return "SHA512"
case x509.DSAWithSHA1:
return "SHA1"
case x509.DSAWithSHA256:
return "SHA256"
case x509.ECDSAWithSHA1:
return "SHA1"
case x509.ECDSAWithSHA256:
return "SHA256"
case x509.ECDSAWithSHA384:
return "SHA384"
case x509.ECDSAWithSHA512:
return "SHA512"
default:
return "Unknown Hash Algorithm"
}
}
// StringTLSVersion returns underlying enum values from human names for TLS
// versions, defaults to current golang default of TLS 1.0
func StringTLSVersion(version string) uint16 {
switch version {
case "1.2":
return tls.VersionTLS12
case "1.1":
return tls.VersionTLS11
default:
return tls.VersionTLS10
}
}
// EncodeCertificatesPEM encodes a number of x509 certificates to PEM
func EncodeCertificatesPEM(certs []*x509.Certificate) []byte {
var buffer bytes.Buffer
for _, cert := range certs {
pem.Encode(&buffer, &pem.Block{
Type: "CERTIFICATE",
Bytes: cert.Raw,
})
}
return buffer.Bytes()
}
// EncodeCertificatePEM encodes a single x509 certificates to PEM
func EncodeCertificatePEM(cert *x509.Certificate) []byte {
return EncodeCertificatesPEM([]*x509.Certificate{cert})
}
// ParseCertificatesPEM parses a sequence of PEM-encoded certificate and returns them,
// can handle PEM encoded PKCS #7 structures.
func ParseCertificatesPEM(certsPEM []byte) ([]*x509.Certificate, error) {
var certs []*x509.Certificate
var err error
certsPEM = bytes.TrimSpace(certsPEM)
for len(certsPEM) > 0 {
var cert []*x509.Certificate
cert, certsPEM, err = ParseOneCertificateFromPEM(certsPEM)
if err != nil {
return nil, cferr.New(cferr.CertificateError, cferr.ParseFailed)
} else if cert == nil {
break
}
certs = append(certs, cert...)
}
if len(certsPEM) > 0 {
return nil, cferr.New(cferr.CertificateError, cferr.DecodeFailed)
}
return certs, nil
}
// ParseCertificatesDER parses a DER encoding of a certificate object and possibly private key,
// either PKCS #7, PKCS #12, or raw x509.
func ParseCertificatesDER(certsDER []byte, password string) (certs []*x509.Certificate, key crypto.Signer, err error) {
certsDER = bytes.TrimSpace(certsDER)
pkcs7data, err := pkcs7.ParsePKCS7(certsDER)
if err != nil {
var pkcs12data interface{}
certs = make([]*x509.Certificate, 1)
pkcs12data, certs[0], err = pkcs12.Decode(certsDER, password)
if err != nil {
certs, err = x509.ParseCertificates(certsDER)
if err != nil {
return nil, nil, cferr.New(cferr.CertificateError, cferr.DecodeFailed)
}
} else {
key = pkcs12data.(crypto.Signer)
}
} else {
if pkcs7data.ContentInfo != "SignedData" {
return nil, nil, cferr.Wrap(cferr.CertificateError, cferr.DecodeFailed, errors.New("can only extract certificates from signed data content info"))
}
certs = pkcs7data.Content.SignedData.Certificates
}
if certs == nil {
return nil, key, cferr.New(cferr.CertificateError, cferr.DecodeFailed)
}
return certs, key, nil
}
// ParseSelfSignedCertificatePEM parses a PEM-encoded certificate and check if it is self-signed.
func ParseSelfSignedCertificatePEM(certPEM []byte) (*x509.Certificate, error) {
cert, err := ParseCertificatePEM(certPEM)
if err != nil {
return nil, err
}
if err := cert.CheckSignature(cert.SignatureAlgorithm, cert.RawTBSCertificate, cert.Signature); err != nil {
return nil, cferr.Wrap(cferr.CertificateError, cferr.VerifyFailed, err)
}
return cert, nil
}
// ParseCertificatePEM parses and returns a PEM-encoded certificate,
// can handle PEM encoded PKCS #7 structures.
func ParseCertificatePEM(certPEM []byte) (*x509.Certificate, error) {
certPEM = bytes.TrimSpace(certPEM)
cert, rest, err := ParseOneCertificateFromPEM(certPEM)
if err != nil {
// Log the actual parsing error but throw a default parse error message.
log.Debugf("Certificate parsing error: %v", err)
return nil, cferr.New(cferr.CertificateError, cferr.ParseFailed)
} else if cert == nil {
return nil, cferr.New(cferr.CertificateError, cferr.DecodeFailed)
} else if len(rest) > 0 {
return nil, cferr.Wrap(cferr.CertificateError, cferr.ParseFailed, errors.New("the PEM file should contain only one object"))
} else if len(cert) > 1 {
return nil, cferr.Wrap(cferr.CertificateError, cferr.ParseFailed, errors.New("the PKCS7 object in the PEM file should contain only one certificate"))
}
return cert[0], nil
}
// ParseOneCertificateFromPEM attempts to parse one PEM encoded certificate object,
// either a raw x509 certificate or a PKCS #7 structure possibly containing
// multiple certificates, from the top of certsPEM, which itself may
// contain multiple PEM encoded certificate objects.
func ParseOneCertificateFromPEM(certsPEM []byte) ([]*x509.Certificate, []byte, error) {
block, rest := pem.Decode(certsPEM)
if block == nil {
return nil, rest, nil
}
cert, err := x509.ParseCertificate(block.Bytes)
if err != nil {
pkcs7data, err := pkcs7.ParsePKCS7(block.Bytes)
if err != nil {
return nil, rest, err
}
if pkcs7data.ContentInfo != "SignedData" {
return nil, rest, errors.New("only PKCS #7 Signed Data Content Info supported for certificate parsing")
}
certs := pkcs7data.Content.SignedData.Certificates
if certs == nil {
return nil, rest, errors.New("PKCS #7 structure contains no certificates")
}
return certs, rest, nil
}
var certs = []*x509.Certificate{cert}
return certs, rest, nil
}
// LoadPEMCertPool loads a pool of PEM certificates from file.
func LoadPEMCertPool(certsFile string) (*x509.CertPool, error) {
if certsFile == "" {
return nil, nil
}
pemCerts, err := ioutil.ReadFile(certsFile)
if err != nil {
return nil, err
}
return PEMToCertPool(pemCerts)
}
// PEMToCertPool concerts PEM certificates to a CertPool.
func PEMToCertPool(pemCerts []byte) (*x509.CertPool, error) {
if len(pemCerts) == 0 {
return nil, nil
}
certPool := x509.NewCertPool()
if !certPool.AppendCertsFromPEM(pemCerts) {
return nil, errors.New("failed to load cert pool")
}
return certPool, nil
}
// ParsePrivateKeyPEM parses and returns a PEM-encoded private
// key. The private key may be either an unencrypted PKCS#8, PKCS#1,
// or elliptic private key.
func ParsePrivateKeyPEM(keyPEM []byte) (key crypto.Signer, err error) {
return ParsePrivateKeyPEMWithPassword(keyPEM, nil)
}
// ParsePrivateKeyPEMWithPassword parses and returns a PEM-encoded private
// key. The private key may be a potentially encrypted PKCS#8, PKCS#1,
// or elliptic private key.
func ParsePrivateKeyPEMWithPassword(keyPEM []byte, password []byte) (key crypto.Signer, err error) {
keyDER, err := GetKeyDERFromPEM(keyPEM, password)
if err != nil {
return nil, err
}
return derhelpers.ParsePrivateKeyDER(keyDER)
}
// GetKeyDERFromPEM parses a PEM-encoded private key and returns DER-format key bytes.
func GetKeyDERFromPEM(in []byte, password []byte) ([]byte, error) {
keyDER, _ := pem.Decode(in)
if keyDER != nil {
if procType, ok := keyDER.Headers["Proc-Type"]; ok {
if strings.Contains(procType, "ENCRYPTED") {
if password != nil {
return x509.DecryptPEMBlock(keyDER, password)
}
return nil, cferr.New(cferr.PrivateKeyError, cferr.Encrypted)
}
}
return keyDER.Bytes, nil
}
return nil, cferr.New(cferr.PrivateKeyError, cferr.DecodeFailed)
}
// ParseCSR parses a PEM- or DER-encoded PKCS #10 certificate signing request.
func ParseCSR(in []byte) (csr *x509.CertificateRequest, rest []byte, err error) {
in = bytes.TrimSpace(in)
p, rest := pem.Decode(in)
if p != nil {
if p.Type != "NEW CERTIFICATE REQUEST" && p.Type != "CERTIFICATE REQUEST" {
return nil, rest, cferr.New(cferr.CSRError, cferr.BadRequest)
}
csr, err = x509.ParseCertificateRequest(p.Bytes)
} else {
csr, err = x509.ParseCertificateRequest(in)
}
if err != nil {
return nil, rest, err
}
err = csr.CheckSignature()
if err != nil {
return nil, rest, err
}
return csr, rest, nil
}
// ParseCSRPEM parses a PEM-encoded certificate signing request.
// It does not check the signature. This is useful for dumping data from a CSR
// locally.
func ParseCSRPEM(csrPEM []byte) (*x509.CertificateRequest, error) {
block, _ := pem.Decode([]byte(csrPEM))
if block == nil {
return nil, cferr.New(cferr.CSRError, cferr.DecodeFailed)
}
csrObject, err := x509.ParseCertificateRequest(block.Bytes)
if err != nil {
return nil, err
}
return csrObject, nil
}
// SignerAlgo returns an X.509 signature algorithm from a crypto.Signer.
func SignerAlgo(priv crypto.Signer) x509.SignatureAlgorithm {
switch pub := priv.Public().(type) {
case *rsa.PublicKey:
bitLength := pub.N.BitLen()
switch {
case bitLength >= 4096:
return x509.SHA512WithRSA
case bitLength >= 3072:
return x509.SHA384WithRSA
case bitLength >= 2048:
return x509.SHA256WithRSA
default:
return x509.SHA1WithRSA
}
case *ecdsa.PublicKey:
switch pub.Curve {
case elliptic.P521():
return x509.ECDSAWithSHA512
case elliptic.P384():
return x509.ECDSAWithSHA384
case elliptic.P256():
return x509.ECDSAWithSHA256
default:
return x509.ECDSAWithSHA1
}
default:
return x509.UnknownSignatureAlgorithm
}
}
// LoadClientCertificate load key/certificate from pem files
func LoadClientCertificate(certFile string, keyFile string) (*tls.Certificate, error) {
if certFile != "" && keyFile != "" {
cert, err := tls.LoadX509KeyPair(certFile, keyFile)
if err != nil {
log.Critical("Unable to read client certificate from file: %s or key from file: %s", certFile, keyFile)
return nil, err
}
log.Debug("Client certificate loaded ")
return &cert, nil
}
return nil, nil
}
// CreateTLSConfig creates a tls.Config object from certs and roots
func CreateTLSConfig(remoteCAs *x509.CertPool, cert *tls.Certificate) *tls.Config {
var certs []tls.Certificate
if cert != nil {
certs = []tls.Certificate{*cert}
}
return &tls.Config{
Certificates: certs,
RootCAs: remoteCAs,
}
}
// SerializeSCTList serializes a list of SCTs.
func SerializeSCTList(sctList []ct.SignedCertificateTimestamp) ([]byte, error) {
list := ctx509.SignedCertificateTimestampList{}
for _, sct := range sctList {
sctBytes, err := cttls.Marshal(sct)
if err != nil {
return nil, err
}
list.SCTList = append(list.SCTList, ctx509.SerializedSCT{Val: sctBytes})
}
return cttls.Marshal(list)
}
// DeserializeSCTList deserializes a list of SCTs.
func DeserializeSCTList(serializedSCTList []byte) ([]ct.SignedCertificateTimestamp, error) {
var sctList ctx509.SignedCertificateTimestampList
rest, err := cttls.Unmarshal(serializedSCTList, &sctList)
if err != nil {
return nil, err
}
if len(rest) != 0 {
return nil, cferr.Wrap(cferr.CTError, cferr.Unknown, errors.New("serialized SCT list contained trailing garbage"))
}
list := make([]ct.SignedCertificateTimestamp, len(sctList.SCTList))
for i, serializedSCT := range sctList.SCTList {
var sct ct.SignedCertificateTimestamp
rest, err := cttls.Unmarshal(serializedSCT.Val, &sct)
if err != nil {
return nil, err
}
if len(rest) != 0 {
return nil, cferr.Wrap(cferr.CTError, cferr.Unknown, errors.New("serialized SCT contained trailing garbage"))
}
list[i] = sct
}
return list, nil
}
// SCTListFromOCSPResponse extracts the SCTList from an ocsp.Response,
// returning an empty list if the SCT extension was not found or could not be
// unmarshalled.
func SCTListFromOCSPResponse(response *ocsp.Response) ([]ct.SignedCertificateTimestamp, error) {
// This loop finds the SCTListExtension in the OCSP response.
var SCTListExtension, ext pkix.Extension
for _, ext = range response.Extensions {
// sctExtOid is the ObjectIdentifier of a Signed Certificate Timestamp.
sctExtOid := asn1.ObjectIdentifier{1, 3, 6, 1, 4, 1, 11129, 2, 4, 5}
if ext.Id.Equal(sctExtOid) {
SCTListExtension = ext
break
}
}
// This code block extracts the sctList from the SCT extension.
var sctList []ct.SignedCertificateTimestamp
var err error
if numBytes := len(SCTListExtension.Value); numBytes != 0 {
var serializedSCTList []byte
rest := make([]byte, numBytes)
copy(rest, SCTListExtension.Value)
for len(rest) != 0 {
rest, err = asn1.Unmarshal(rest, &serializedSCTList)
if err != nil {
return nil, cferr.Wrap(cferr.CTError, cferr.Unknown, err)
}
}
sctList, err = DeserializeSCTList(serializedSCTList)
}
return sctList, err
}
// ReadBytes reads a []byte either from a file or an environment variable.
// If valFile has a prefix of 'env:', the []byte is read from the environment
// using the subsequent name. If the prefix is 'file:' the []byte is read from
// the subsequent file. If no prefix is provided, valFile is assumed to be a
// file path.
func ReadBytes(valFile string) ([]byte, error) {
switch splitVal := strings.SplitN(valFile, ":", 2); len(splitVal) {
case 1:
return ioutil.ReadFile(valFile)
case 2:
switch splitVal[0] {
case "env":
return []byte(os.Getenv(splitVal[1])), nil
case "file":
return ioutil.ReadFile(splitVal[1])
default:
return nil, fmt.Errorf("unknown prefix: %s", splitVal[0])
}
default:
return nil, fmt.Errorf("multiple prefixes: %s",
strings.Join(splitVal[:len(splitVal)-1], ", "))
}
}