/
ca.go
912 lines (820 loc) · 29.6 KB
/
ca.go
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package ca
import (
"bytes"
"context"
"crypto"
"crypto/ecdsa"
"crypto/rand"
"crypto/rsa"
"crypto/sha256"
"crypto/x509"
"encoding/asn1"
"encoding/hex"
"encoding/json"
"encoding/pem"
"errors"
"fmt"
"math/big"
"strings"
"time"
"github.com/beeker1121/goque"
cfsslConfig "github.com/cloudflare/cfssl/config"
cferr "github.com/cloudflare/cfssl/errors"
"github.com/cloudflare/cfssl/signer"
"github.com/cloudflare/cfssl/signer/local"
ct "github.com/google/certificate-transparency-go"
cttls "github.com/google/certificate-transparency-go/tls"
"github.com/jmhodges/clock"
"github.com/miekg/pkcs11"
"github.com/prometheus/client_golang/prometheus"
"golang.org/x/crypto/ocsp"
ca_config "github.com/letsencrypt/boulder/ca/config"
capb "github.com/letsencrypt/boulder/ca/proto"
"github.com/letsencrypt/boulder/core"
corepb "github.com/letsencrypt/boulder/core/proto"
csrlib "github.com/letsencrypt/boulder/csr"
berrors "github.com/letsencrypt/boulder/errors"
"github.com/letsencrypt/boulder/features"
"github.com/letsencrypt/boulder/goodkey"
blog "github.com/letsencrypt/boulder/log"
sapb "github.com/letsencrypt/boulder/sa/proto"
)
// Miscellaneous PKIX OIDs that we need to refer to
var (
// X.509 Extensions
oidAuthorityInfoAccess = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 1, 1}
oidAuthorityKeyIdentifier = asn1.ObjectIdentifier{2, 5, 29, 35}
oidBasicConstraints = asn1.ObjectIdentifier{2, 5, 29, 19}
oidCertificatePolicies = asn1.ObjectIdentifier{2, 5, 29, 32}
oidCrlDistributionPoints = asn1.ObjectIdentifier{2, 5, 29, 31}
oidExtKeyUsage = asn1.ObjectIdentifier{2, 5, 29, 37}
oidKeyUsage = asn1.ObjectIdentifier{2, 5, 29, 15}
oidSubjectAltName = asn1.ObjectIdentifier{2, 5, 29, 17}
oidSubjectKeyIdentifier = asn1.ObjectIdentifier{2, 5, 29, 14}
oidTLSFeature = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 1, 24}
// CSR attribute requesting extensions
oidExtensionRequest = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 9, 14}
)
// OID and fixed value for the "must staple" variant of the TLS Feature
// extension:
//
// Features ::= SEQUENCE OF INTEGER [RFC7633]
// enum { ... status_request(5) ...} ExtensionType; [RFC6066]
//
// DER Encoding:
// 30 03 - SEQUENCE (3 octets)
// |-- 02 01 - INTEGER (1 octet)
// | |-- 05 - 5
var (
mustStapleFeatureValue = []byte{0x30, 0x03, 0x02, 0x01, 0x05}
mustStapleExtension = signer.Extension{
ID: cfsslConfig.OID(oidTLSFeature),
Critical: false,
Value: hex.EncodeToString(mustStapleFeatureValue),
}
// https://tools.ietf.org/html/rfc6962#section-3.1
ctPoisonExtension = signer.Extension{
ID: cfsslConfig.OID(signer.CTPoisonOID),
Critical: true,
Value: "0500", // ASN.1 DER NULL, Hex encoded.
}
)
// Metrics for CA statistics
const (
csrExtensionCategory = "category"
csrExtensionBasic = "basic"
csrExtensionTLSFeature = "tls-feature"
csrExtensionTLSFeatureInvalid = "tls-feature-invalid"
csrExtensionOther = "other"
)
type certificateStorage interface {
AddCertificate(context.Context, []byte, int64, []byte, *time.Time) (string, error)
GetCertificate(context.Context, string) (core.Certificate, error)
AddPrecertificate(ctx context.Context, req *sapb.AddCertificateRequest) (*corepb.Empty, error)
AddSerial(ctx context.Context, req *sapb.AddSerialRequest) (*corepb.Empty, error)
}
type certificateType string
const (
precertType = certificateType("precertificate")
certType = certificateType("certificate")
)
// CertificateAuthorityImpl represents a CA that signs certificates, CRLs, and
// OCSP responses.
type CertificateAuthorityImpl struct {
rsaProfile string
ecdsaProfile string
// A map from issuer cert common name to an internalIssuer struct
issuers map[string]*internalIssuer
// A map from issuer ID to internalIssuer
idToIssuer map[int64]*internalIssuer
// The common name of the default issuer cert
defaultIssuer *internalIssuer
sa certificateStorage
pa core.PolicyAuthority
keyPolicy goodkey.KeyPolicy
clk clock.Clock
log blog.Logger
prefix int // Prepended to the serial number
validityPeriod time.Duration
backdate time.Duration
maxNames int
forceCNFromSAN bool
signatureCount *prometheus.CounterVec
csrExtensionCount *prometheus.CounterVec
orphanCount *prometheus.CounterVec
adoptedOrphanCount *prometheus.CounterVec
signErrorCounter *prometheus.CounterVec
orphanQueue *goque.Queue
ocspLifetime time.Duration
}
// Issuer represents a single issuer certificate, along with its key.
type Issuer struct {
Signer crypto.Signer
Cert *x509.Certificate
}
// localSigner is an interface describing the functions of a cfssl.local.Signer
// that the Boulder CA uses. It allows mocking the local.Signer in unit tests.
type localSigner interface {
Sign(signer.SignRequest) ([]byte, error)
SignFromPrecert(*x509.Certificate, []ct.SignedCertificateTimestamp) ([]byte, error)
}
// internalIssuer represents the fully initialized internal state for a single
// issuer, including the cfssl signer and OCSP signer objects.
type internalIssuer struct {
cert *x509.Certificate
eeSigner localSigner
ocspSigner crypto.Signer
}
func makeInternalIssuers(
issuers []Issuer,
policy *cfsslConfig.Signing,
lifespanOCSP time.Duration,
) (map[string]*internalIssuer, error) {
if len(issuers) == 0 {
return nil, errors.New("No issuers specified.")
}
internalIssuers := make(map[string]*internalIssuer)
for _, iss := range issuers {
if iss.Cert == nil || iss.Signer == nil {
return nil, errors.New("Issuer with nil cert or signer specified.")
}
eeSigner, err := local.NewSigner(iss.Signer, iss.Cert, x509.SHA256WithRSA, policy)
if err != nil {
return nil, err
}
cn := iss.Cert.Subject.CommonName
if internalIssuers[cn] != nil {
return nil, errors.New("Multiple issuer certs with the same CommonName are not supported")
}
internalIssuers[cn] = &internalIssuer{
cert: iss.Cert,
eeSigner: eeSigner,
ocspSigner: iss.Signer,
}
}
return internalIssuers, nil
}
// idForIssuer generates a stable ID for an issuer certificate. This
// is used for identifying which issuer issued a certificate in the
// certificateStatus table.
func idForIssuer(cert *x509.Certificate) int64 {
h := sha256.Sum256(cert.Raw)
return big.NewInt(0).SetBytes(h[:4]).Int64()
}
// NewCertificateAuthorityImpl creates a CA instance that can sign certificates
// from a single issuer (the first first in the issuers slice), and can sign OCSP
// for any of the issuer certificates provided.
func NewCertificateAuthorityImpl(
config ca_config.CAConfig,
sa certificateStorage,
pa core.PolicyAuthority,
clk clock.Clock,
stats prometheus.Registerer,
issuers []Issuer,
keyPolicy goodkey.KeyPolicy,
logger blog.Logger,
orphanQueue *goque.Queue,
) (*CertificateAuthorityImpl, error) {
var ca *CertificateAuthorityImpl
var err error
if config.SerialPrefix <= 0 || config.SerialPrefix >= 256 {
err = errors.New("Must have a positive non-zero serial prefix less than 256 for CA.")
return nil, err
}
// CFSSL requires processing JSON configs through its own LoadConfig, so we
// serialize and then deserialize.
cfsslJSON, err := json.Marshal(config.CFSSL)
if err != nil {
return nil, err
}
cfsslConfigObj, err := cfsslConfig.LoadConfig(cfsslJSON)
if err != nil {
return nil, err
}
if config.LifespanOCSP.Duration == 0 {
return nil, errors.New("Config must specify an OCSP lifespan period.")
}
for _, profile := range cfsslConfigObj.Signing.Profiles {
if len(profile.IssuerURL) > 1 {
return nil, errors.New("only one issuer_url supported")
}
}
internalIssuers, err := makeInternalIssuers(
issuers,
cfsslConfigObj.Signing,
config.LifespanOCSP.Duration)
if err != nil {
return nil, err
}
defaultIssuer := internalIssuers[issuers[0].Cert.Subject.CommonName]
rsaProfile := config.RSAProfile
ecdsaProfile := config.ECDSAProfile
if rsaProfile == "" || ecdsaProfile == "" {
return nil, errors.New("must specify rsaProfile and ecdsaProfile")
}
csrExtensionCount := prometheus.NewCounterVec(
prometheus.CounterOpts{
Name: "csr_extensions",
Help: "Number of CSRs with extensions of the given category",
},
[]string{csrExtensionCategory})
stats.MustRegister(csrExtensionCount)
signatureCount := prometheus.NewCounterVec(
prometheus.CounterOpts{
Name: "signatures",
Help: "Number of signatures",
},
[]string{"purpose"})
stats.MustRegister(signatureCount)
orphanCount := prometheus.NewCounterVec(
prometheus.CounterOpts{
Name: "orphans",
Help: "Number of orphaned certificates labelled by type (precert, cert)",
},
[]string{"type"})
stats.MustRegister(orphanCount)
adoptedOrphanCount := prometheus.NewCounterVec(
prometheus.CounterOpts{
Name: "adopted_orphans",
Help: "Number of orphaned certificates adopted from the orphan queue by type (precert, cert)",
},
[]string{"type"})
stats.MustRegister(adoptedOrphanCount)
signErrorCounter := prometheus.NewCounterVec(prometheus.CounterOpts{
Name: "signature_errors",
Help: "A counter of signature errors labelled by error type",
}, []string{"type"})
stats.MustRegister(signErrorCounter)
ca = &CertificateAuthorityImpl{
sa: sa,
pa: pa,
issuers: internalIssuers,
defaultIssuer: defaultIssuer,
rsaProfile: rsaProfile,
ecdsaProfile: ecdsaProfile,
prefix: config.SerialPrefix,
clk: clk,
log: logger,
keyPolicy: keyPolicy,
forceCNFromSAN: !config.DoNotForceCN, // Note the inversion here
signatureCount: signatureCount,
csrExtensionCount: csrExtensionCount,
orphanCount: orphanCount,
adoptedOrphanCount: adoptedOrphanCount,
orphanQueue: orphanQueue,
ocspLifetime: config.LifespanOCSP.Duration,
signErrorCounter: signErrorCounter,
}
ca.idToIssuer = make(map[int64]*internalIssuer)
for _, ii := range ca.issuers {
id := idForIssuer(ii.cert)
ca.idToIssuer[id] = ii
}
if config.Expiry == "" {
return nil, errors.New("Config must specify an expiry period.")
}
ca.validityPeriod, err = time.ParseDuration(config.Expiry)
if err != nil {
return nil, err
}
// TODO(briansmith): Make the backdate setting mandatory after the
// production ca.json has been updated to include it. Until then, manually
// default to 1h, which is the backdating duration we currently use.
ca.backdate = config.Backdate.Duration
if ca.backdate == 0 {
ca.backdate = time.Hour
}
ca.maxNames = config.MaxNames
return ca, nil
}
// noteSignError is called after operations that may cause a CFSSL
// or PKCS11 signing error.
func (ca *CertificateAuthorityImpl) noteSignError(err error) {
if _, ok := err.(*pkcs11.Error); ok {
ca.signErrorCounter.WithLabelValues("HSM").Inc()
} else if cfErr, ok := err.(*cferr.Error); ok {
ca.signErrorCounter.WithLabelValues(fmt.Sprintf("CFSSL %d", cfErr.ErrorCode)).Inc()
}
}
// Extract supported extensions from a CSR. The following extensions are
// currently supported:
//
// * 1.3.6.1.5.5.7.1.24 - TLS Feature [RFC7633], with the "must staple" value.
// Any other value will result in an error.
//
// Other requested extensions are silently ignored.
func (ca *CertificateAuthorityImpl) extensionsFromCSR(csr *x509.CertificateRequest) ([]signer.Extension, error) {
extensions := []signer.Extension{}
extensionSeen := map[string]bool{}
hasBasic := false
hasOther := false
for _, attr := range csr.Attributes {
if !attr.Type.Equal(oidExtensionRequest) {
continue
}
for _, extList := range attr.Value {
for _, ext := range extList {
if extensionSeen[ext.Type.String()] {
// Ignore duplicate certificate extensions
continue
}
extensionSeen[ext.Type.String()] = true
switch {
case ext.Type.Equal(oidTLSFeature):
ca.csrExtensionCount.With(prometheus.Labels{csrExtensionCategory: csrExtensionTLSFeature}).Inc()
value, ok := ext.Value.([]byte)
if !ok {
return nil, berrors.MalformedError("malformed extension with OID %v", ext.Type)
} else if !bytes.Equal(value, mustStapleFeatureValue) {
ca.csrExtensionCount.With(prometheus.Labels{csrExtensionCategory: csrExtensionTLSFeatureInvalid}).Inc()
return nil, berrors.MalformedError("unsupported value for extension with OID %v", ext.Type)
}
extensions = append(extensions, mustStapleExtension)
case ext.Type.Equal(oidAuthorityInfoAccess),
ext.Type.Equal(oidAuthorityKeyIdentifier),
ext.Type.Equal(oidBasicConstraints),
ext.Type.Equal(oidCertificatePolicies),
ext.Type.Equal(oidCrlDistributionPoints),
ext.Type.Equal(oidExtKeyUsage),
ext.Type.Equal(oidKeyUsage),
ext.Type.Equal(oidSubjectAltName),
ext.Type.Equal(oidSubjectKeyIdentifier):
hasBasic = true
default:
hasOther = true
}
}
}
}
if hasBasic {
ca.csrExtensionCount.With(prometheus.Labels{csrExtensionCategory: csrExtensionBasic}).Inc()
}
if hasOther {
ca.csrExtensionCount.With(prometheus.Labels{csrExtensionCategory: csrExtensionOther}).Inc()
}
return extensions, nil
}
var ocspStatusToCode = map[string]int{
"good": ocsp.Good,
"revoked": ocsp.Revoked,
"unknown": ocsp.Unknown,
}
// GenerateOCSP produces a new OCSP response and returns it
func (ca *CertificateAuthorityImpl) GenerateOCSP(ctx context.Context, req *capb.GenerateOCSPRequest) (*capb.OCSPResponse, error) {
// req.Status, req.Reason, and req.RevokedAt are often 0, for non-revoked certs.
// Either CertDER or both (Serial and IssuerID) must be non-zero.
if core.IsAnyNilOrZero(req, req.CertDER) && core.IsAnyNilOrZero(req, req.Serial, req.IssuerID) {
return nil, berrors.InternalServerError("Incomplete generate OCSP request")
}
var issuer *internalIssuer
var serial *big.Int
// Once the feature is enabled we need to support both RPCs that include
// IssuerID and those that don't as we still need to be able to update rows
// that didn't have an IssuerID set when they were created. Once this feature
// has been enabled for a full OCSP lifetime cycle we can remove this
// functionality.
if features.Enabled(features.StoreIssuerInfo) && req.IssuerID != nil {
serialInt, err := core.StringToSerial(*req.Serial)
if err != nil {
return nil, err
}
serial = serialInt
var ok bool
issuer, ok = ca.idToIssuer[*req.IssuerID]
if !ok {
return nil, fmt.Errorf("This CA doesn't have an issuer cert with ID %d", *req.IssuerID)
}
} else {
cert, err := x509.ParseCertificate(req.CertDER)
if err != nil {
ca.log.AuditErr(err.Error())
return nil, err
}
serial = cert.SerialNumber
cn := cert.Issuer.CommonName
issuer = ca.issuers[cn]
if issuer == nil {
return nil, fmt.Errorf("This CA doesn't have an issuer cert with CommonName %q", cn)
}
err = cert.CheckSignatureFrom(issuer.cert)
if err != nil {
return nil, fmt.Errorf("GenerateOCSP was asked to sign OCSP for cert "+
"%s from %q, but the cert's signature was not valid: %s.",
core.SerialToString(cert.SerialNumber), cn, err)
}
}
now := ca.clk.Now().Truncate(time.Hour)
tbsResponse := ocsp.Response{
Status: ocspStatusToCode[*req.Status],
SerialNumber: serial,
ThisUpdate: now,
NextUpdate: now.Add(ca.ocspLifetime),
}
if tbsResponse.Status == ocsp.Revoked {
tbsResponse.RevokedAt = time.Unix(0, *req.RevokedAt)
tbsResponse.RevocationReason = int(*req.Reason)
}
ocspResponse, err := ocsp.CreateResponse(issuer.cert, issuer.cert, tbsResponse, issuer.ocspSigner)
ca.noteSignError(err)
if err == nil {
ca.signatureCount.With(prometheus.Labels{"purpose": "ocsp"}).Inc()
}
return &capb.OCSPResponse{Response: ocspResponse}, err
}
func (ca *CertificateAuthorityImpl) IssuePrecertificate(ctx context.Context, issueReq *capb.IssueCertificateRequest) (*capb.IssuePrecertificateResponse, error) {
// issueReq.orderID may be zero, for ACMEv1 requests.
if core.IsAnyNilOrZero(issueReq, issueReq.Csr, issueReq.RegistrationID) {
return nil, berrors.InternalServerError("Incomplete issue certificate request")
}
serialBigInt, validity, err := ca.generateSerialNumberAndValidity()
if err != nil {
return nil, err
}
regID := *issueReq.RegistrationID
serialHex := core.SerialToString(serialBigInt)
nowNanos := ca.clk.Now().UnixNano()
expiresNanos := validity.NotAfter.UnixNano()
_, err = ca.sa.AddSerial(ctx, &sapb.AddSerialRequest{
Serial: &serialHex,
RegID: ®ID,
Created: &nowNanos,
Expires: &expiresNanos,
})
if err != nil {
return nil, err
}
precertDER, err := ca.issuePrecertificateInner(ctx, issueReq, serialBigInt, validity)
if err != nil {
return nil, err
}
status := string(core.OCSPStatusGood)
ocspResp, err := ca.GenerateOCSP(ctx, &capb.GenerateOCSPRequest{
CertDER: precertDER,
Status: &status,
})
if err != nil {
err = berrors.InternalServerError(err.Error())
ca.log.AuditInfof("OCSP Signing failure: serial=[%s] err=[%s]", serialHex, err)
return nil, err
}
req := &sapb.AddCertificateRequest{
Der: precertDER,
RegID: ®ID,
Ocsp: ocspResp.Response,
Issued: &nowNanos,
}
// we currently only use one issuer, in the future when we support multiple
// the issuer will need to be derived from issueReq
issuerID := idForIssuer(ca.defaultIssuer.cert)
req.IssuerID = &issuerID
_, err = ca.sa.AddPrecertificate(ctx, req)
if err != nil {
ca.orphanCount.With(prometheus.Labels{"type": "precert"}).Inc()
err = berrors.InternalServerError(err.Error())
// Note: This log line is parsed by cmd/orphan-finder. If you make any
// changes here, you should make sure they are reflected in orphan-finder.
ca.log.AuditErrf("Failed RPC to store at SA, orphaning precertificate: serial=[%s] cert=[%s] err=[%v], regID=[%d], orderID=[%d]",
serialHex, hex.EncodeToString(precertDER), err, *issueReq.RegistrationID, *issueReq.OrderID)
if ca.orphanQueue != nil {
ca.queueOrphan(&orphanedCert{
DER: precertDER,
RegID: regID,
OCSPResp: ocspResp.Response,
Precert: true,
})
}
return nil, err
}
return &capb.IssuePrecertificateResponse{
DER: precertDER,
}, nil
}
// IssueCertificateForPrecertificate takes a precertificate and a set
// of SCTs for that precertificate and uses the signer to create and
// sign a certificate from them. The poison extension is removed and a
// SCT list extension is inserted in its place. Except for this and the
// signature the certificate exactly matches the precertificate. After
// the certificate is signed a OCSP response is generated and the
// response and certificate are stored in the database.
//
// It's critical not to sign two different final certificates for the same
// precertificate. This can happen, for instance, if the caller provides a
// different set of SCTs on subsequent calls to IssueCertificateForPrecertificate.
// We rely on the RA not to call IssueCertificateForPrecertificate twice for the
// same serial. This is accomplished by the fact that
// IssueCertificateForPrecertificate is only ever called in a straight-through
// RPC path without retries. If there is any error, including a networking
// error, the whole certificate issuance attempt fails and any subsequent
// issuance will use a different serial number.
//
// We also check that the provided serial number does not already exist as a
// final certificate, but this is just a belt-and-suspenders measure, since
// there could be race conditions where two goroutines are issuing for the same
// serial number at the same time.
func (ca *CertificateAuthorityImpl) IssueCertificateForPrecertificate(ctx context.Context, req *capb.IssueCertificateForPrecertificateRequest) (*corepb.Certificate, error) {
// issueReq.orderID may be zero, for ACMEv1 requests.
if core.IsAnyNilOrZero(req, req.DER, req.SCTs, req.RegistrationID) {
return nil, berrors.InternalServerError("Incomplete cert for precertificate request")
}
precert, err := x509.ParseCertificate(req.DER)
if err != nil {
return nil, err
}
serialHex := core.SerialToString(precert.SerialNumber)
if _, err = ca.sa.GetCertificate(ctx, serialHex); err == nil {
err = berrors.InternalServerError("issuance of duplicate final certificate requested: %s", serialHex)
ca.log.AuditErr(err.Error())
return nil, err
} else if !berrors.Is(err, berrors.NotFound) {
return nil, fmt.Errorf("error checking for duplicate issuance of %s: %s", serialHex, err)
}
var scts []ct.SignedCertificateTimestamp
for _, sctBytes := range req.SCTs {
var sct ct.SignedCertificateTimestamp
_, err = cttls.Unmarshal(sctBytes, &sct)
if err != nil {
return nil, err
}
scts = append(scts, sct)
}
certPEM, err := ca.defaultIssuer.eeSigner.SignFromPrecert(precert, scts)
if err != nil {
return nil, err
}
ca.signatureCount.WithLabelValues(string(certType)).Inc()
block, _ := pem.Decode(certPEM)
if block == nil || block.Type != "CERTIFICATE" {
err = berrors.InternalServerError("invalid certificate value returned")
ca.log.AuditErrf("PEM decode error, aborting: serial=[%s] pem=[%s] err=[%v]", serialHex, certPEM, err)
return nil, err
}
certDER := block.Bytes
ca.log.AuditInfof("Signing success: serial=[%s] names=[%s] certificate=[%s]",
serialHex, strings.Join(precert.DNSNames, ", "), hex.EncodeToString(req.DER),
hex.EncodeToString(certDER))
err = ca.storeCertificate(ctx, *req.RegistrationID, *req.OrderID, precert.SerialNumber, certDER)
if err != nil {
return nil, err
}
serialString := core.SerialToString(precert.SerialNumber)
digest := core.Fingerprint256(certDER)
issued := precert.NotBefore.UnixNano()
expires := precert.NotAfter.UnixNano()
return &corepb.Certificate{
RegistrationID: req.RegistrationID,
Serial: &serialString,
Der: certDER,
Digest: &digest,
Issued: &issued,
Expires: &expires,
}, nil
}
type validity struct {
NotBefore time.Time
NotAfter time.Time
}
func (ca *CertificateAuthorityImpl) generateSerialNumberAndValidity() (*big.Int, validity, error) {
// We want 136 bits of random number, plus an 8-bit instance id prefix.
const randBits = 136
serialBytes := make([]byte, randBits/8+1)
serialBytes[0] = byte(ca.prefix)
_, err := rand.Read(serialBytes[1:])
if err != nil {
err = berrors.InternalServerError("failed to generate serial: %s", err)
ca.log.AuditErrf("Serial randomness failed, err=[%v]", err)
return nil, validity{}, err
}
serialBigInt := big.NewInt(0)
serialBigInt = serialBigInt.SetBytes(serialBytes)
notBefore := ca.clk.Now().Add(-1 * ca.backdate)
validity := validity{
NotBefore: notBefore,
NotAfter: notBefore.Add(ca.validityPeriod),
}
return serialBigInt, validity, nil
}
func (ca *CertificateAuthorityImpl) issuePrecertificateInner(ctx context.Context, issueReq *capb.IssueCertificateRequest, serialBigInt *big.Int, validity validity) ([]byte, error) {
csr, err := x509.ParseCertificateRequest(issueReq.Csr)
if err != nil {
return nil, err
}
if err := csrlib.VerifyCSR(
ctx,
csr,
ca.maxNames,
&ca.keyPolicy,
ca.pa,
ca.forceCNFromSAN,
*issueReq.RegistrationID,
); err != nil {
ca.log.AuditErr(err.Error())
// VerifyCSR returns berror instances that can be passed through as-is
// without wrapping.
return nil, err
}
extensions, err := ca.extensionsFromCSR(csr)
if err != nil {
return nil, err
}
issuer := ca.defaultIssuer
if issuer.cert.NotAfter.Before(validity.NotAfter) {
err = berrors.InternalServerError("cannot issue a certificate that expires after the issuer certificate")
ca.log.AuditErr(err.Error())
return nil, err
}
// Convert the CSR to PEM
csrPEM := string(pem.EncodeToMemory(&pem.Block{
Type: "CERTIFICATE REQUEST",
Bytes: csr.Raw,
}))
var profile string
switch csr.PublicKey.(type) {
case *rsa.PublicKey:
profile = ca.rsaProfile
case *ecdsa.PublicKey:
profile = ca.ecdsaProfile
default:
err = berrors.InternalServerError("unsupported key type %T", csr.PublicKey)
ca.log.AuditErr(err.Error())
return nil, err
}
// Send the cert off for signing
req := signer.SignRequest{
Request: csrPEM,
Profile: profile,
Hosts: csr.DNSNames,
Subject: &signer.Subject{
CN: csr.Subject.CommonName,
},
Serial: serialBigInt,
Extensions: extensions,
NotBefore: validity.NotBefore,
NotAfter: validity.NotAfter,
ReturnPrecert: true,
}
serialHex := core.SerialToString(serialBigInt)
if !ca.forceCNFromSAN {
req.Subject.SerialNumber = serialHex
}
ca.log.AuditInfof("Signing: serial=[%s] names=[%s] csr=[%s]",
serialHex, strings.Join(csr.DNSNames, ", "), hex.EncodeToString(csr.Raw))
certPEM, err := issuer.eeSigner.Sign(req)
ca.noteSignError(err)
if err != nil {
// If the Signing error was a pre-issuance lint error then marshal the
// linting errors to include in the audit err msg.
if lErr, ok := err.(*local.LintError); ok {
// NOTE(@cpu): We throw away the JSON marshal error here. If marshaling
// fails for some reason it's acceptable to log an empty string for the
// JSON component.
lintErrsJSON, _ := json.Marshal(lErr.ErrorResults)
ca.log.AuditErrf("Signing failed: serial=[%s] err=[%v] lintErrors=%s",
serialHex, err, string(lintErrsJSON))
return nil, berrors.InternalServerError("failed to sign certificate: %s", err)
}
err = berrors.InternalServerError("failed to sign certificate: %s", err)
ca.log.AuditErrf("Signing failed: serial=[%s] err=[%v]", serialHex, err)
return nil, err
}
ca.signatureCount.WithLabelValues(string(precertType)).Inc()
if len(certPEM) == 0 {
err = berrors.InternalServerError("no certificate returned by server")
ca.log.AuditErrf("PEM empty from Signer: serial=[%s] err=[%v]", serialHex, err)
return nil, err
}
block, _ := pem.Decode(certPEM)
if block == nil || block.Type != "CERTIFICATE" {
err = berrors.InternalServerError("invalid certificate value returned")
ca.log.AuditErrf("PEM decode error, aborting: serial=[%s] pem=[%s] err=[%v]", serialHex, certPEM, err)
return nil, err
}
certDER := block.Bytes
ca.log.AuditInfof("Signing success: serial=[%s] names=[%s] csr=[%s] precertificate=[%s]",
serialHex, strings.Join(csr.DNSNames, ", "), hex.EncodeToString(csr.Raw),
hex.EncodeToString(certDER))
return certDER, nil
}
func (ca *CertificateAuthorityImpl) storeCertificate(
ctx context.Context,
regID int64,
orderID int64,
serialBigInt *big.Int,
certDER []byte) error {
var err error
now := ca.clk.Now()
_, err = ca.sa.AddCertificate(ctx, certDER, regID, nil, &now)
if err != nil {
ca.orphanCount.With(prometheus.Labels{"type": "cert"}).Inc()
err = berrors.InternalServerError(err.Error())
// Note: This log line is parsed by cmd/orphan-finder. If you make any
// changes here, you should make sure they are reflected in orphan-finder.
ca.log.AuditErrf("Failed RPC to store at SA, orphaning certificate: serial=[%s] cert=[%s] err=[%v], regID=[%d], orderID=[%d]",
core.SerialToString(serialBigInt), hex.EncodeToString(certDER), err, regID, orderID)
if ca.orphanQueue != nil {
ca.queueOrphan(&orphanedCert{
DER: certDER,
RegID: regID,
})
}
return err
}
return nil
}
type orphanedCert struct {
DER []byte
OCSPResp []byte
RegID int64
Precert bool
}
func (ca *CertificateAuthorityImpl) queueOrphan(o *orphanedCert) {
if _, err := ca.orphanQueue.EnqueueObject(o); err != nil {
ca.log.AuditErrf("failed to queue orphan for integration: %s", err)
}
}
// OrphanIntegrationLoop runs a loop executing integrateOrphans and then waiting a minute.
// It is split out into a separate function called directly by boulder-ca in order to make
// testing the orphan queue functionality somewhat more simple.
func (ca *CertificateAuthorityImpl) OrphanIntegrationLoop() {
for {
if err := ca.integrateOrphan(); err != nil {
if err == goque.ErrEmpty {
time.Sleep(time.Minute)
continue
}
ca.log.AuditErrf("failed to integrate orphaned certs: %s", err)
time.Sleep(time.Second)
}
}
}
// integrateOrpan removes an orphan from the queue and adds it to the database. The
// item isn't dequeued until it is actually added to the database to prevent items from
// being lost if the CA is restarted between the item being dequeued and being added to
// the database. It calculates the issuance time by subtracting the backdate period from
// the notBefore time.
func (ca *CertificateAuthorityImpl) integrateOrphan() error {
item, err := ca.orphanQueue.Peek()
if err != nil {
if err == goque.ErrEmpty {
return goque.ErrEmpty
}
return fmt.Errorf("failed to peek into orphan queue: %s", err)
}
var orphan orphanedCert
if err = item.ToObject(&orphan); err != nil {
return fmt.Errorf("failed to marshal orphan: %s", err)
}
cert, err := x509.ParseCertificate(orphan.DER)
if err != nil {
return fmt.Errorf("failed to parse orphan: %s", err)
}
// When calculating the `NotBefore` at issuance time, we subtracted
// ca.backdate. Now, to calculate the actual issuance time from the NotBefore,
// we reverse the process and add ca.backdate.
issued := cert.NotBefore.Add(ca.backdate)
if orphan.Precert {
issuedNanos := issued.UnixNano()
_, err = ca.sa.AddPrecertificate(context.Background(), &sapb.AddCertificateRequest{
Der: orphan.DER,
RegID: &orphan.RegID,
Ocsp: orphan.OCSPResp,
Issued: &issuedNanos,
})
if err != nil && !berrors.Is(err, berrors.Duplicate) {
return fmt.Errorf("failed to store orphaned precertificate: %s", err)
}
} else {
_, err = ca.sa.AddCertificate(context.Background(), orphan.DER, orphan.RegID, nil, &issued)
if err != nil && !berrors.Is(err, berrors.Duplicate) {
return fmt.Errorf("failed to store orphaned certificate: %s", err)
}
}
if _, err = ca.orphanQueue.Dequeue(); err != nil {
return fmt.Errorf("failed to dequeue integrated orphaned certificate: %s", err)
}
typ := "cert"
if orphan.Precert {
typ = "precert"
}
ca.adoptedOrphanCount.With(prometheus.Labels{"type": typ}).Inc()
return nil
}