open-vault/builtin/credential/aws/pkcs7/pkcs7.go
2022-01-27 10:06:34 -08:00

291 lines
9.5 KiB
Go

// Package pkcs7 implements parsing and generation of some PKCS#7 structures.
package pkcs7
import (
"bytes"
"crypto"
"crypto/dsa"
"crypto/ecdsa"
"crypto/rsa"
"crypto/x509"
"crypto/x509/pkix"
"encoding/asn1"
"errors"
"fmt"
"sort"
_ "crypto/sha1" // for crypto.SHA1
)
// PKCS7 Represents a PKCS7 structure
type PKCS7 struct {
Content []byte
Certificates []*x509.Certificate
CRLs []pkix.CertificateList
Signers []signerInfo
raw interface{}
}
type contentInfo struct {
ContentType asn1.ObjectIdentifier
Content asn1.RawValue `asn1:"explicit,optional,tag:0"`
}
// ErrUnsupportedContentType is returned when a PKCS7 content is not supported.
// Currently only Data (1.2.840.113549.1.7.1), Signed Data (1.2.840.113549.1.7.2),
// and Enveloped Data are supported (1.2.840.113549.1.7.3)
var ErrUnsupportedContentType = errors.New("pkcs7: cannot parse data: unimplemented content type")
type unsignedData []byte
var (
// Signed Data OIDs
OIDData = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 7, 1}
OIDSignedData = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 7, 2}
OIDEnvelopedData = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 7, 3}
OIDEncryptedData = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 7, 6}
OIDAttributeContentType = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 9, 3}
OIDAttributeMessageDigest = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 9, 4}
OIDAttributeSigningTime = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 9, 5}
// Digest Algorithms
OIDDigestAlgorithmSHA1 = asn1.ObjectIdentifier{1, 3, 14, 3, 2, 26}
OIDDigestAlgorithmSHA256 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 1}
OIDDigestAlgorithmSHA384 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 2}
OIDDigestAlgorithmSHA512 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 3}
OIDDigestAlgorithmDSA = asn1.ObjectIdentifier{1, 2, 840, 10040, 4, 1}
OIDDigestAlgorithmDSASHA1 = asn1.ObjectIdentifier{1, 2, 840, 10040, 4, 3}
OIDDigestAlgorithmECDSASHA1 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 1}
OIDDigestAlgorithmECDSASHA256 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 2}
OIDDigestAlgorithmECDSASHA384 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 3}
OIDDigestAlgorithmECDSASHA512 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 4}
// Signature Algorithms
OIDEncryptionAlgorithmRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 1}
OIDEncryptionAlgorithmRSASHA1 = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 5}
OIDEncryptionAlgorithmRSASHA256 = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 11}
OIDEncryptionAlgorithmRSASHA384 = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 12}
OIDEncryptionAlgorithmRSASHA512 = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 13}
OIDEncryptionAlgorithmECDSAP256 = asn1.ObjectIdentifier{1, 2, 840, 10045, 3, 1, 7}
OIDEncryptionAlgorithmECDSAP384 = asn1.ObjectIdentifier{1, 3, 132, 0, 34}
OIDEncryptionAlgorithmECDSAP521 = asn1.ObjectIdentifier{1, 3, 132, 0, 35}
// Encryption Algorithms
OIDEncryptionAlgorithmDESCBC = asn1.ObjectIdentifier{1, 3, 14, 3, 2, 7}
OIDEncryptionAlgorithmDESEDE3CBC = asn1.ObjectIdentifier{1, 2, 840, 113549, 3, 7}
OIDEncryptionAlgorithmAES256CBC = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 1, 42}
OIDEncryptionAlgorithmAES128GCM = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 1, 6}
OIDEncryptionAlgorithmAES128CBC = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 1, 2}
OIDEncryptionAlgorithmAES256GCM = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 1, 46}
)
func getHashForOID(oid asn1.ObjectIdentifier) (crypto.Hash, error) {
switch {
case oid.Equal(OIDDigestAlgorithmSHA1), oid.Equal(OIDDigestAlgorithmECDSASHA1),
oid.Equal(OIDDigestAlgorithmDSA), oid.Equal(OIDDigestAlgorithmDSASHA1),
oid.Equal(OIDEncryptionAlgorithmRSA):
return crypto.SHA1, nil
case oid.Equal(OIDDigestAlgorithmSHA256), oid.Equal(OIDDigestAlgorithmECDSASHA256):
return crypto.SHA256, nil
case oid.Equal(OIDDigestAlgorithmSHA384), oid.Equal(OIDDigestAlgorithmECDSASHA384):
return crypto.SHA384, nil
case oid.Equal(OIDDigestAlgorithmSHA512), oid.Equal(OIDDigestAlgorithmECDSASHA512):
return crypto.SHA512, nil
}
return crypto.Hash(0), ErrUnsupportedAlgorithm
}
// getDigestOIDForSignatureAlgorithm takes an x509.SignatureAlgorithm
// and returns the corresponding OID digest algorithm
func getDigestOIDForSignatureAlgorithm(digestAlg x509.SignatureAlgorithm) (asn1.ObjectIdentifier, error) {
switch digestAlg {
case x509.SHA1WithRSA, x509.ECDSAWithSHA1:
return OIDDigestAlgorithmSHA1, nil
case x509.SHA256WithRSA, x509.ECDSAWithSHA256:
return OIDDigestAlgorithmSHA256, nil
case x509.SHA384WithRSA, x509.ECDSAWithSHA384:
return OIDDigestAlgorithmSHA384, nil
case x509.SHA512WithRSA, x509.ECDSAWithSHA512:
return OIDDigestAlgorithmSHA512, nil
}
return nil, fmt.Errorf("pkcs7: cannot convert hash to oid, unknown hash algorithm")
}
// getOIDForEncryptionAlgorithm takes the private key type of the signer and
// the OID of a digest algorithm to return the appropriate signerInfo.DigestEncryptionAlgorithm
func getOIDForEncryptionAlgorithm(pkey crypto.PrivateKey, OIDDigestAlg asn1.ObjectIdentifier) (asn1.ObjectIdentifier, error) {
switch pkey.(type) {
case *rsa.PrivateKey:
switch {
default:
return OIDEncryptionAlgorithmRSA, nil
case OIDDigestAlg.Equal(OIDEncryptionAlgorithmRSA):
return OIDEncryptionAlgorithmRSA, nil
case OIDDigestAlg.Equal(OIDDigestAlgorithmSHA1):
return OIDEncryptionAlgorithmRSASHA1, nil
case OIDDigestAlg.Equal(OIDDigestAlgorithmSHA256):
return OIDEncryptionAlgorithmRSASHA256, nil
case OIDDigestAlg.Equal(OIDDigestAlgorithmSHA384):
return OIDEncryptionAlgorithmRSASHA384, nil
case OIDDigestAlg.Equal(OIDDigestAlgorithmSHA512):
return OIDEncryptionAlgorithmRSASHA512, nil
}
case *ecdsa.PrivateKey:
switch {
case OIDDigestAlg.Equal(OIDDigestAlgorithmSHA1):
return OIDDigestAlgorithmECDSASHA1, nil
case OIDDigestAlg.Equal(OIDDigestAlgorithmSHA256):
return OIDDigestAlgorithmECDSASHA256, nil
case OIDDigestAlg.Equal(OIDDigestAlgorithmSHA384):
return OIDDigestAlgorithmECDSASHA384, nil
case OIDDigestAlg.Equal(OIDDigestAlgorithmSHA512):
return OIDDigestAlgorithmECDSASHA512, nil
}
case *dsa.PrivateKey:
return OIDDigestAlgorithmDSA, nil
}
return nil, fmt.Errorf("pkcs7: cannot convert encryption algorithm to oid, unknown private key type %T", pkey)
}
// Parse decodes a DER encoded PKCS7 package
func Parse(data []byte) (p7 *PKCS7, err error) {
if len(data) == 0 {
return nil, errors.New("pkcs7: input data is empty")
}
var info contentInfo
der, err := ber2der(data)
if err != nil {
return nil, err
}
rest, err := asn1.Unmarshal(der, &info)
if len(rest) > 0 {
err = asn1.SyntaxError{Msg: "trailing data"}
return
}
if err != nil {
return
}
// fmt.Printf("--> Content Type: %s", info.ContentType)
switch {
case info.ContentType.Equal(OIDSignedData):
return parseSignedData(info.Content.Bytes)
case info.ContentType.Equal(OIDEnvelopedData):
return parseEnvelopedData(info.Content.Bytes)
case info.ContentType.Equal(OIDEncryptedData):
return parseEncryptedData(info.Content.Bytes)
}
return nil, ErrUnsupportedContentType
}
func parseEnvelopedData(data []byte) (*PKCS7, error) {
var ed envelopedData
if _, err := asn1.Unmarshal(data, &ed); err != nil {
return nil, err
}
return &PKCS7{
raw: ed,
}, nil
}
func parseEncryptedData(data []byte) (*PKCS7, error) {
var ed encryptedData
if _, err := asn1.Unmarshal(data, &ed); err != nil {
return nil, err
}
return &PKCS7{
raw: ed,
}, nil
}
func (raw rawCertificates) Parse() ([]*x509.Certificate, error) {
if len(raw.Raw) == 0 {
return nil, nil
}
var val asn1.RawValue
if _, err := asn1.Unmarshal(raw.Raw, &val); err != nil {
return nil, err
}
return x509.ParseCertificates(val.Bytes)
}
func isCertMatchForIssuerAndSerial(cert *x509.Certificate, ias issuerAndSerial) bool {
return cert.SerialNumber.Cmp(ias.SerialNumber) == 0 && bytes.Equal(cert.RawIssuer, ias.IssuerName.FullBytes)
}
// Attribute represents a key value pair attribute. Value must be marshalable byte
// `encoding/asn1`
type Attribute struct {
Type asn1.ObjectIdentifier
Value interface{}
}
type attributes struct {
types []asn1.ObjectIdentifier
values []interface{}
}
// Add adds the attribute, maintaining insertion order
func (attrs *attributes) Add(attrType asn1.ObjectIdentifier, value interface{}) {
attrs.types = append(attrs.types, attrType)
attrs.values = append(attrs.values, value)
}
type sortableAttribute struct {
SortKey []byte
Attribute attribute
}
type attributeSet []sortableAttribute
func (sa attributeSet) Len() int {
return len(sa)
}
func (sa attributeSet) Less(i, j int) bool {
return bytes.Compare(sa[i].SortKey, sa[j].SortKey) < 0
}
func (sa attributeSet) Swap(i, j int) {
sa[i], sa[j] = sa[j], sa[i]
}
func (sa attributeSet) Attributes() []attribute {
attrs := make([]attribute, len(sa))
for i, attr := range sa {
attrs[i] = attr.Attribute
}
return attrs
}
func (attrs *attributes) ForMarshalling() ([]attribute, error) {
sortables := make(attributeSet, len(attrs.types))
for i := range sortables {
attrType := attrs.types[i]
attrValue := attrs.values[i]
asn1Value, err := asn1.Marshal(attrValue)
if err != nil {
return nil, err
}
attr := attribute{
Type: attrType,
Value: asn1.RawValue{Tag: 17, IsCompound: true, Bytes: asn1Value}, // 17 == SET tag
}
encoded, err := asn1.Marshal(attr)
if err != nil {
return nil, err
}
sortables[i] = sortableAttribute{
SortKey: encoded,
Attribute: attr,
}
}
sort.Sort(sortables)
return sortables.Attributes(), nil
}