// Helper function to perform a remote sign or info request.
func (s *Signer) remoteOp(req interface{}, profile, target string) (resp interface{}, err error) {
jsonData, err := json.Marshal(req)
if err != nil {
return nil, cferr.Wrap(cferr.APIClientError, cferr.JSONError, err)
}
p, err := signer.Profile(s, profile)
if err != nil {
return
}
server := client.NewServer(p.RemoteServer)
if server == nil {
return nil, cferr.Wrap(cferr.PolicyError, cferr.InvalidRequest,
errors.New("failed to connect to remote"))
}
// There's no auth provider for the "info" method
if target == "info" {
resp, err = server.Info(jsonData)
} else if p.RemoteProvider != nil {
resp, err = server.AuthSign(jsonData, nil, p.RemoteProvider)
} else {
resp, err = server.Sign(jsonData)
}
if err != nil {
return nil, err
}
return
}
// Handle responds to requests for the CA to sign the certificate request
// present in the "certificate_request" parameter for the host named
// in the "hostname" parameter. The certificate should be PEM-encoded. If
// provided, subject information from the "subject" parameter will be used
// in place of the subject information from the CSR.
func (h *Handler) Handle(w http.ResponseWriter, r *http.Request) error {
log.Info("signature request received")
body, err := ioutil.ReadAll(r.Body)
if err != nil {
return err
}
r.Body.Close()
var req jsonSignRequest
err = json.Unmarshal(body, &req)
if err != nil {
return errors.NewBadRequestString("Unable to parse sign request")
}
signReq := jsonReqToTrue(req)
if req.Request == "" {
return errors.NewBadRequestString("missing parameter 'certificate_request'")
}
var cert []byte
profile, err := signer.Profile(h.signer, req.Profile)
if err != nil {
return err
}
if profile.Provider != nil {
log.Error("profile requires authentication")
return errors.NewBadRequestString("authentication required")
}
cert, err = h.signer.Sign(signReq)
if err != nil {
log.Warningf("failed to sign request: %v", err)
return err
}
result := map[string]string{"certificate": string(cert)}
log.Info("wrote response")
return api.SendResponse(w, result)
}
// Info return a populated info.Resp struct or an error.
func (s *Signer) Info(req info.Req) (resp *info.Resp, err error) {
cert, err := s.Certificate(req.Label, req.Profile)
if err != nil {
return
}
profile, err := signer.Profile(s, req.Profile)
if err != nil {
return
}
resp = new(info.Resp)
if cert.Raw != nil {
resp.Certificate = string(bytes.TrimSpace(pem.EncodeToMemory(&pem.Block{Type: "CERTIFICATE", Bytes: cert.Raw})))
}
resp.Usage = profile.Usage
resp.ExpiryString = profile.ExpiryString
return
}
// Sign signs a new certificate based on the PEM-encoded client
// certificate or certificate request with the signing profile,
// specified by profileName.
func (s *Signer) Sign(req signer.SignRequest) (cert []byte, err error) {
profile, err := signer.Profile(s, req.Profile)
if err != nil {
return
}
block, _ := pem.Decode([]byte(req.Request))
if block == nil {
return nil, cferr.New(cferr.CSRError, cferr.DecodeFailed)
}
if block.Type != "CERTIFICATE REQUEST" {
return nil, cferr.Wrap(cferr.CSRError,
cferr.BadRequest, errors.New("not a certificate or csr"))
}
csrTemplate, err := signer.ParseCertificateRequest(s, block.Bytes)
if err != nil {
return nil, err
}
// Copy out only the fields from the CSR authorized by policy.
safeTemplate := x509.Certificate{}
// If the profile contains no explicit whitelist, assume that all fields
// should be copied from the CSR.
if profile.CSRWhitelist == nil {
safeTemplate = *csrTemplate
} else {
if profile.CSRWhitelist.Subject {
safeTemplate.Subject = csrTemplate.Subject
}
if profile.CSRWhitelist.PublicKeyAlgorithm {
safeTemplate.PublicKeyAlgorithm = csrTemplate.PublicKeyAlgorithm
}
if profile.CSRWhitelist.PublicKey {
safeTemplate.PublicKey = csrTemplate.PublicKey
}
if profile.CSRWhitelist.SignatureAlgorithm {
safeTemplate.SignatureAlgorithm = csrTemplate.SignatureAlgorithm
}
if profile.CSRWhitelist.DNSNames {
safeTemplate.DNSNames = csrTemplate.DNSNames
}
if profile.CSRWhitelist.IPAddresses {
safeTemplate.IPAddresses = csrTemplate.IPAddresses
}
}
OverrideHosts(&safeTemplate, req.Hosts)
safeTemplate.Subject = PopulateSubjectFromCSR(req.Subject, safeTemplate.Subject)
// If there is a whitelist, ensure that both the Common Name and SAN DNSNames match
if profile.NameWhitelist != nil {
if safeTemplate.Subject.CommonName != "" {
if profile.NameWhitelist.Find([]byte(safeTemplate.Subject.CommonName)) == nil {
return nil, cferr.New(cferr.PolicyError, cferr.InvalidPolicy)
}
}
for _, name := range safeTemplate.DNSNames {
if profile.NameWhitelist.Find([]byte(name)) == nil {
return nil, cferr.New(cferr.PolicyError, cferr.InvalidPolicy)
}
}
}
if profile.ClientProvidesSerialNumbers {
if req.Serial == nil {
fmt.Printf("xx %#v\n", profile)
return nil, cferr.New(cferr.CertificateError, cferr.MissingSerial)
}
safeTemplate.SerialNumber = req.Serial
} else {
// RFC 5280 4.1.2.2:
// Certificate users MUST be able to handle serialNumber
// values up to 20 octets. Conforming CAs MUST NOT use
// serialNumber values longer than 20 octets.
//
// If CFSSL is providing the serial numbers, it makes
// sense to use the max supported size.
serialNumber := make([]byte, 20)
_, err = io.ReadFull(rand.Reader, serialNumber)
if err != nil {
return nil, cferr.Wrap(cferr.CertificateError, cferr.Unknown, err)
}
// SetBytes interprets buf as the bytes of a big-endian
// unsigned integer. The leading byte should be masked
// off to ensure it isn't negative.
serialNumber[0] &= 0x7F
safeTemplate.SerialNumber = new(big.Int).SetBytes(serialNumber)
}
if len(req.Extensions) > 0 {
for _, ext := range req.Extensions {
oid := asn1.ObjectIdentifier(ext.ID)
if !profile.ExtensionWhitelist[oid.String()] {
return nil, cferr.New(cferr.CertificateError, cferr.InvalidRequest)
}
rawValue, err := hex.DecodeString(ext.Value)
if err != nil {
return nil, cferr.Wrap(cferr.CertificateError, cferr.InvalidRequest, err)
}
safeTemplate.ExtraExtensions = append(safeTemplate.ExtraExtensions, pkix.Extension{
Id: oid,
Critical: ext.Critical,
Value: rawValue,
})
}
}
var certTBS = safeTemplate
if len(profile.CTLogServers) > 0 {
// Add a poison extension which prevents validation
var poisonExtension = pkix.Extension{Id: signer.CTPoisonOID, Critical: true, Value: []byte{0x05, 0x00}}
var poisonedPreCert = certTBS
poisonedPreCert.ExtraExtensions = append(safeTemplate.ExtraExtensions, poisonExtension)
cert, err = s.sign(&poisonedPreCert, profile)
if err != nil {
return
}
derCert, _ := pem.Decode(cert)
prechain := []ct.ASN1Cert{derCert.Bytes, s.ca.Raw}
var sctList []ct.SignedCertificateTimestamp
for _, server := range profile.CTLogServers {
log.Infof("submitting poisoned precertificate to %s", server)
var ctclient = client.New(server)
var resp *ct.SignedCertificateTimestamp
resp, err = ctclient.AddPreChain(prechain)
if err != nil {
return nil, cferr.Wrap(cferr.CTError, cferr.PrecertSubmissionFailed, err)
}
sctList = append(sctList, *resp)
}
var serializedSCTList []byte
serializedSCTList, err = serializeSCTList(sctList)
if err != nil {
return nil, cferr.Wrap(cferr.CTError, cferr.Unknown, err)
}
// Serialize again as an octet string before embedding
serializedSCTList, err = asn1.Marshal(serializedSCTList)
if err != nil {
return nil, cferr.Wrap(cferr.CTError, cferr.Unknown, err)
}
var SCTListExtension = pkix.Extension{Id: signer.SCTListOID, Critical: false, Value: serializedSCTList}
certTBS.ExtraExtensions = append(certTBS.ExtraExtensions, SCTListExtension)
}
var signedCert []byte
signedCert, err = s.sign(&certTBS, profile)
if err != nil {
return nil, err
}
if s.db != nil {
var certRecord = &certdb.CertificateRecord{
Serial: certTBS.SerialNumber.String(),
CALabel: req.Label,
Status: "good",
Expiry: certTBS.NotAfter,
PEM: string(signedCert),
}
err = certdb.InsertCertificate(s.db, certRecord)
if err != nil {
return nil, err
}
log.Debug("saved certificate with serial number ", certTBS.SerialNumber)
}
return signedCert, nil
}
// Handle receives the incoming request, validates it, and processes it.
func (h *AuthHandler) Handle(w http.ResponseWriter, r *http.Request) error {
log.Info("signature request received")
body, err := ioutil.ReadAll(r.Body)
if err != nil {
log.Errorf("failed to read response body: %v", err)
return err
}
r.Body.Close()
var aReq auth.AuthenticatedRequest
err = json.Unmarshal(body, &aReq)
if err != nil {
log.Errorf("failed to unmarshal authenticated request: %v", err)
return errors.NewBadRequest(err)
}
var req jsonSignRequest
err = json.Unmarshal(aReq.Request, &req)
if err != nil {
log.Errorf("failed to unmarshal request from authenticated request: %v", err)
return errors.NewBadRequestString("Unable to parse authenticated sign request")
}
// Sanity checks to ensure that we have a valid policy. This
// should have been checked in NewAuthHandler.
policy := h.signer.Policy()
if policy == nil {
log.Critical("signer was initialised without a signing policy")
return errors.NewBadRequestString("invalid policy")
}
profile, err := signer.Profile(h.signer, req.Profile)
if err != nil {
return err
}
if profile.Provider == nil {
log.Error("profile has no authentication provider")
return errors.NewBadRequestString("no authentication provider")
}
if !profile.Provider.Verify(&aReq) {
log.Warning("received authenticated request with invalid token")
return errors.NewBadRequestString("invalid token")
}
signReq := jsonReqToTrue(req)
if signReq.Request == "" {
return errors.NewBadRequestString("missing parameter 'certificate_request'")
}
cert, err := h.signer.Sign(signReq)
if err != nil {
log.Errorf("signature failed: %v", err)
return err
}
result := map[string]string{"certificate": string(cert)}
log.Info("wrote response")
return api.SendResponse(w, result)
}