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author | TomSweeneyRedHat <tsweeney@redhat.com> | 2020-08-03 14:34:20 -0400 |
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committer | TomSweeneyRedHat <tsweeney@redhat.com> | 2020-08-03 14:34:24 -0400 |
commit | 47c91097f7b93045e9c099b52870c35577f80734 (patch) | |
tree | fd63e9de155376c5f6f8ac021045a258cf491994 /vendor/go.mozilla.org/pkcs7/sign.go | |
parent | 1709335cf04e947117d4ae4dca72f24f4095511b (diff) | |
download | podman-47c91097f7b93045e9c099b52870c35577f80734.tar.gz podman-47c91097f7b93045e9c099b52870c35577f80734.tar.bz2 podman-47c91097f7b93045e9c099b52870c35577f80734.zip |
Bump to Buildah 1.16.0-dev in upstream
Bump Buildah to v1.16.0-dev in the upstream branch
of Podman. This will allow us to get a number of new
issues into the upstream branch for use. The version of
Buildah will need to be bumped to v1.16.0 and then
vendored into Podman before we release Podman v2.0
Signed-off-by: TomSweeneyRedHat <tsweeney@redhat.com>
Diffstat (limited to 'vendor/go.mozilla.org/pkcs7/sign.go')
-rw-r--r-- | vendor/go.mozilla.org/pkcs7/sign.go | 429 |
1 files changed, 429 insertions, 0 deletions
diff --git a/vendor/go.mozilla.org/pkcs7/sign.go b/vendor/go.mozilla.org/pkcs7/sign.go new file mode 100644 index 000000000..addd76383 --- /dev/null +++ b/vendor/go.mozilla.org/pkcs7/sign.go @@ -0,0 +1,429 @@ +package pkcs7 + +import ( + "bytes" + "crypto" + "crypto/dsa" + "crypto/rand" + "crypto/x509" + "crypto/x509/pkix" + "encoding/asn1" + "errors" + "fmt" + "math/big" + "time" +) + +// SignedData is an opaque data structure for creating signed data payloads +type SignedData struct { + sd signedData + certs []*x509.Certificate + data, messageDigest []byte + digestOid asn1.ObjectIdentifier + encryptionOid asn1.ObjectIdentifier +} + +// NewSignedData takes data and initializes a PKCS7 SignedData struct that is +// ready to be signed via AddSigner. The digest algorithm is set to SHA1 by default +// and can be changed by calling SetDigestAlgorithm. +func NewSignedData(data []byte) (*SignedData, error) { + content, err := asn1.Marshal(data) + if err != nil { + return nil, err + } + ci := contentInfo{ + ContentType: OIDData, + Content: asn1.RawValue{Class: 2, Tag: 0, Bytes: content, IsCompound: true}, + } + sd := signedData{ + ContentInfo: ci, + Version: 1, + } + return &SignedData{sd: sd, data: data, digestOid: OIDDigestAlgorithmSHA1}, nil +} + +// SignerInfoConfig are optional values to include when adding a signer +type SignerInfoConfig struct { + ExtraSignedAttributes []Attribute + ExtraUnsignedAttributes []Attribute +} + +type signedData struct { + Version int `asn1:"default:1"` + DigestAlgorithmIdentifiers []pkix.AlgorithmIdentifier `asn1:"set"` + ContentInfo contentInfo + Certificates rawCertificates `asn1:"optional,tag:0"` + CRLs []pkix.CertificateList `asn1:"optional,tag:1"` + SignerInfos []signerInfo `asn1:"set"` +} + +type signerInfo struct { + Version int `asn1:"default:1"` + IssuerAndSerialNumber issuerAndSerial + DigestAlgorithm pkix.AlgorithmIdentifier + AuthenticatedAttributes []attribute `asn1:"optional,omitempty,tag:0"` + DigestEncryptionAlgorithm pkix.AlgorithmIdentifier + EncryptedDigest []byte + UnauthenticatedAttributes []attribute `asn1:"optional,omitempty,tag:1"` +} + +type attribute struct { + Type asn1.ObjectIdentifier + Value asn1.RawValue `asn1:"set"` +} + +func marshalAttributes(attrs []attribute) ([]byte, error) { + encodedAttributes, err := asn1.Marshal(struct { + A []attribute `asn1:"set"` + }{A: attrs}) + if err != nil { + return nil, err + } + + // Remove the leading sequence octets + var raw asn1.RawValue + asn1.Unmarshal(encodedAttributes, &raw) + return raw.Bytes, nil +} + +type rawCertificates struct { + Raw asn1.RawContent +} + +type issuerAndSerial struct { + IssuerName asn1.RawValue + SerialNumber *big.Int +} + +// SetDigestAlgorithm sets the digest algorithm to be used in the signing process. +// +// This should be called before adding signers +func (sd *SignedData) SetDigestAlgorithm(d asn1.ObjectIdentifier) { + sd.digestOid = d +} + +// SetEncryptionAlgorithm sets the encryption algorithm to be used in the signing process. +// +// This should be called before adding signers +func (sd *SignedData) SetEncryptionAlgorithm(d asn1.ObjectIdentifier) { + sd.encryptionOid = d +} + +// AddSigner is a wrapper around AddSignerChain() that adds a signer without any parent. +func (sd *SignedData) AddSigner(ee *x509.Certificate, pkey crypto.PrivateKey, config SignerInfoConfig) error { + var parents []*x509.Certificate + return sd.AddSignerChain(ee, pkey, parents, config) +} + +// AddSignerChain signs attributes about the content and adds certificates +// and signers infos to the Signed Data. The certificate and private key +// of the end-entity signer are used to issue the signature, and any +// parent of that end-entity that need to be added to the list of +// certifications can be specified in the parents slice. +// +// The signature algorithm used to hash the data is the one of the end-entity +// certificate. +func (sd *SignedData) AddSignerChain(ee *x509.Certificate, pkey crypto.PrivateKey, parents []*x509.Certificate, config SignerInfoConfig) error { +// Following RFC 2315, 9.2 SignerInfo type, the distinguished name of +// the issuer of the end-entity signer is stored in the issuerAndSerialNumber +// section of the SignedData.SignerInfo, alongside the serial number of +// the end-entity. + var ias issuerAndSerial + ias.SerialNumber = ee.SerialNumber + if len(parents) == 0 { + // no parent, the issuer is the end-entity cert itself + ias.IssuerName = asn1.RawValue{FullBytes: ee.RawIssuer} + } else { + err := verifyPartialChain(ee, parents) + if err != nil { + return err + } + // the first parent is the issuer + ias.IssuerName = asn1.RawValue{FullBytes: parents[0].RawSubject} + } + sd.sd.DigestAlgorithmIdentifiers = append(sd.sd.DigestAlgorithmIdentifiers, + pkix.AlgorithmIdentifier{Algorithm: sd.digestOid}, + ) + hash, err := getHashForOID(sd.digestOid) + if err != nil { + return err + } + h := hash.New() + h.Write(sd.data) + sd.messageDigest = h.Sum(nil) + encryptionOid, err := getOIDForEncryptionAlgorithm(pkey, sd.digestOid) + if err != nil { + return err + } + attrs := &attributes{} + attrs.Add(OIDAttributeContentType, sd.sd.ContentInfo.ContentType) + attrs.Add(OIDAttributeMessageDigest, sd.messageDigest) + attrs.Add(OIDAttributeSigningTime, time.Now().UTC()) + for _, attr := range config.ExtraSignedAttributes { + attrs.Add(attr.Type, attr.Value) + } + finalAttrs, err := attrs.ForMarshalling() + if err != nil { + return err + } + unsignedAttrs := &attributes{} + for _, attr := range config.ExtraUnsignedAttributes { + unsignedAttrs.Add(attr.Type, attr.Value) + } + finalUnsignedAttrs, err := unsignedAttrs.ForMarshalling() + if err != nil { + return err + } + // create signature of signed attributes + signature, err := signAttributes(finalAttrs, pkey, hash) + if err != nil { + return err + } + signer := signerInfo{ + AuthenticatedAttributes: finalAttrs, + UnauthenticatedAttributes: finalUnsignedAttrs, + DigestAlgorithm: pkix.AlgorithmIdentifier{Algorithm: sd.digestOid}, + DigestEncryptionAlgorithm: pkix.AlgorithmIdentifier{Algorithm: encryptionOid}, + IssuerAndSerialNumber: ias, + EncryptedDigest: signature, + Version: 1, + } + sd.certs = append(sd.certs, ee) + if len(parents) > 0 { + sd.certs = append(sd.certs, parents...) + } + sd.sd.SignerInfos = append(sd.sd.SignerInfos, signer) + return nil +} + +// SignWithoutAttr issues a signature on the content of the pkcs7 SignedData. +// Unlike AddSigner/AddSignerChain, it calculates the digest on the data alone +// and does not include any signed attributes like timestamp and so on. +// +// This function is needed to sign old Android APKs, something you probably +// shouldn't do unless you're maintaining backward compatibility for old +// applications. +func (sd *SignedData) SignWithoutAttr(ee *x509.Certificate, pkey crypto.PrivateKey, config SignerInfoConfig) error { + var signature []byte + sd.sd.DigestAlgorithmIdentifiers = append(sd.sd.DigestAlgorithmIdentifiers, pkix.AlgorithmIdentifier{Algorithm: sd.digestOid}) + hash, err := getHashForOID(sd.digestOid) + if err != nil { + return err + } + h := hash.New() + h.Write(sd.data) + sd.messageDigest = h.Sum(nil) + switch pkey := pkey.(type) { + case *dsa.PrivateKey: + // dsa doesn't implement crypto.Signer so we make a special case + // https://github.com/golang/go/issues/27889 + r, s, err := dsa.Sign(rand.Reader, pkey, sd.messageDigest) + if err != nil { + return err + } + signature, err = asn1.Marshal(dsaSignature{r, s}) + if err != nil { + return err + } + default: + key, ok := pkey.(crypto.Signer) + if !ok { + return errors.New("pkcs7: private key does not implement crypto.Signer") + } + signature, err = key.Sign(rand.Reader, sd.messageDigest, hash) + if err != nil { + return err + } + } + var ias issuerAndSerial + ias.SerialNumber = ee.SerialNumber + // no parent, the issue is the end-entity cert itself + ias.IssuerName = asn1.RawValue{FullBytes: ee.RawIssuer} + if sd.encryptionOid == nil { + // if the encryption algorithm wasn't set by SetEncryptionAlgorithm, + // infer it from the digest algorithm + sd.encryptionOid, err = getOIDForEncryptionAlgorithm(pkey, sd.digestOid) + } + if err != nil { + return err + } + signer := signerInfo{ + DigestAlgorithm: pkix.AlgorithmIdentifier{Algorithm: sd.digestOid}, + DigestEncryptionAlgorithm: pkix.AlgorithmIdentifier{Algorithm: sd.encryptionOid}, + IssuerAndSerialNumber: ias, + EncryptedDigest: signature, + Version: 1, + } + // create signature of signed attributes + sd.certs = append(sd.certs, ee) + sd.sd.SignerInfos = append(sd.sd.SignerInfos, signer) + return nil +} + +func (si *signerInfo) SetUnauthenticatedAttributes(extraUnsignedAttrs []Attribute) error { + unsignedAttrs := &attributes{} + for _, attr := range extraUnsignedAttrs { + unsignedAttrs.Add(attr.Type, attr.Value) + } + finalUnsignedAttrs, err := unsignedAttrs.ForMarshalling() + if err != nil { + return err + } + + si.UnauthenticatedAttributes = finalUnsignedAttrs + + return nil +} + +// AddCertificate adds the certificate to the payload. Useful for parent certificates +func (sd *SignedData) AddCertificate(cert *x509.Certificate) { + sd.certs = append(sd.certs, cert) +} + +// Detach removes content from the signed data struct to make it a detached signature. +// This must be called right before Finish() +func (sd *SignedData) Detach() { + sd.sd.ContentInfo = contentInfo{ContentType: OIDData} +} + +// GetSignedData returns the private Signed Data +func (sd *SignedData) GetSignedData() *signedData { + return &sd.sd +} + +// Finish marshals the content and its signers +func (sd *SignedData) Finish() ([]byte, error) { + sd.sd.Certificates = marshalCertificates(sd.certs) + inner, err := asn1.Marshal(sd.sd) + if err != nil { + return nil, err + } + outer := contentInfo{ + ContentType: OIDSignedData, + Content: asn1.RawValue{Class: 2, Tag: 0, Bytes: inner, IsCompound: true}, + } + return asn1.Marshal(outer) +} + +// RemoveAuthenticatedAttributes removes authenticated attributes from signedData +// similar to OpenSSL's PKCS7_NOATTR or -noattr flags +func (sd *SignedData) RemoveAuthenticatedAttributes() { + for i := range sd.sd.SignerInfos { + sd.sd.SignerInfos[i].AuthenticatedAttributes = nil + } +} + +// RemoveUnauthenticatedAttributes removes unauthenticated attributes from signedData +func (sd *SignedData) RemoveUnauthenticatedAttributes() { + for i := range sd.sd.SignerInfos { + sd.sd.SignerInfos[i].UnauthenticatedAttributes = nil + } +} + +// verifyPartialChain checks that a given cert is issued by the first parent in the list, +// then continue down the path. It doesn't require the last parent to be a root CA, +// or to be trusted in any truststore. It simply verifies that the chain provided, albeit +// partial, makes sense. +func verifyPartialChain(cert *x509.Certificate, parents []*x509.Certificate) error { + if len(parents) == 0 { + return fmt.Errorf("pkcs7: zero parents provided to verify the signature of certificate %q", cert.Subject.CommonName) + } + err := cert.CheckSignatureFrom(parents[0]) + if err != nil { + return fmt.Errorf("pkcs7: certificate signature from parent is invalid: %v", err) + } + if len(parents) == 1 { + // there is no more parent to check, return + return nil + } + return verifyPartialChain(parents[0], parents[1:]) +} + +func cert2issuerAndSerial(cert *x509.Certificate) (issuerAndSerial, error) { + var ias issuerAndSerial + // The issuer RDNSequence has to match exactly the sequence in the certificate + // We cannot use cert.Issuer.ToRDNSequence() here since it mangles the sequence + ias.IssuerName = asn1.RawValue{FullBytes: cert.RawIssuer} + ias.SerialNumber = cert.SerialNumber + + return ias, nil +} + +// signs the DER encoded form of the attributes with the private key +func signAttributes(attrs []attribute, pkey crypto.PrivateKey, digestAlg crypto.Hash) ([]byte, error) { + attrBytes, err := marshalAttributes(attrs) + if err != nil { + return nil, err + } + h := digestAlg.New() + h.Write(attrBytes) + hash := h.Sum(nil) + + // dsa doesn't implement crypto.Signer so we make a special case + // https://github.com/golang/go/issues/27889 + switch pkey := pkey.(type) { + case *dsa.PrivateKey: + r, s, err := dsa.Sign(rand.Reader, pkey, hash) + if err != nil { + return nil, err + } + return asn1.Marshal(dsaSignature{r, s}) + } + + key, ok := pkey.(crypto.Signer) + if !ok { + return nil, errors.New("pkcs7: private key does not implement crypto.Signer") + } + return key.Sign(rand.Reader, hash, digestAlg) +} + +type dsaSignature struct { + R, S *big.Int +} + +// concats and wraps the certificates in the RawValue structure +func marshalCertificates(certs []*x509.Certificate) rawCertificates { + var buf bytes.Buffer + for _, cert := range certs { + buf.Write(cert.Raw) + } + rawCerts, _ := marshalCertificateBytes(buf.Bytes()) + return rawCerts +} + +// Even though, the tag & length are stripped out during marshalling the +// RawContent, we have to encode it into the RawContent. If its missing, +// then `asn1.Marshal()` will strip out the certificate wrapper instead. +func marshalCertificateBytes(certs []byte) (rawCertificates, error) { + var val = asn1.RawValue{Bytes: certs, Class: 2, Tag: 0, IsCompound: true} + b, err := asn1.Marshal(val) + if err != nil { + return rawCertificates{}, err + } + return rawCertificates{Raw: b}, nil +} + +// DegenerateCertificate creates a signed data structure containing only the +// provided certificate or certificate chain. +func DegenerateCertificate(cert []byte) ([]byte, error) { + rawCert, err := marshalCertificateBytes(cert) + if err != nil { + return nil, err + } + emptyContent := contentInfo{ContentType: OIDData} + sd := signedData{ + Version: 1, + ContentInfo: emptyContent, + Certificates: rawCert, + CRLs: []pkix.CertificateList{}, + } + content, err := asn1.Marshal(sd) + if err != nil { + return nil, err + } + signedContent := contentInfo{ + ContentType: OIDSignedData, + Content: asn1.RawValue{Class: 2, Tag: 0, Bytes: content, IsCompound: true}, + } + return asn1.Marshal(signedContent) +} |