wneessen/go-mail
1
1
Fork 0
mirror of https://github.com/wneessen/go-mail.git synced 2024-12-23 02:50:39 +01:00
Code Issues Projects Releases Packages Wiki Activity

feat: migrated resources from external repo to remove external dependency

Browse source
This commit is contained in:
theexiile1305 2024-10-17 15:48:42 +02:00
parent 128b2bd32e
commit efd8aa93b6
No known key found for this signature in database
GPG key ID: A1BDDE98F2BF6E40
4 changed files with 576 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
go.mod
View file

@ -7,7 +7,6 @@ module github.com/wneessen/go-mail
go 1.16
require (
go.mozilla.org/pkcs7 v0.9.0
golang.org/x/crypto v0.28.0
golang.org/x/text v0.19.0
)
)

2
go.sum
View file

@ -20,8 +20,6 @@ golang.org/x/net v0.10.0/go.mod h1:0qNGK6F8kojg2nk9dLZ2mShWaEBan6FAoqfSigmmuDg=
golang.org/x/net v0.15.0/go.mod h1:idbUs1IY1+zTqbi8yxTbhexhEEk5ur9LInksu6HrEpk=
golang.org/x/net v0.21.0/go.mod h1:bIjVDfnllIU7BJ2DNgfnXvpSvtn8VRwhlsaeUTyUS44=
golang.org/x/net v0.25.0/go.mod h1:JkAGAh7GEvH74S6FOH42FLoXpXbE/aqXSrIQjXgsiwM=
go.mozilla.org/pkcs7 v0.9.0 h1:yM4/HS9dYv7ri2biPtxt8ikvB37a980dg69/pKmS+eI=
go.mozilla.org/pkcs7 v0.9.0/go.mod h1:SNgMg+EgDFwmvSmLRTNKC5fegJjB7v23qTQ0XLGUNHk=
golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=

386
pkcs7.go Normal file
View file

@ -0,0 +1,386 @@
// SPDX-FileCopyrightText: 2022-2023 The go-mail Authors
//
// SPDX-License-Identifier: MIT
package mail
import (
"bytes"
"crypto"
"crypto/rand"
"crypto/rsa"
"crypto/x509"
"crypto/x509/pkix"
"encoding/asn1"
"errors"
"fmt"
"math/big"
"sort"
"time"
_ "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"`
}
var (
oidData = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 7, 1}
oidSignedData = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 7, 2}
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}
)
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 rawCertificates struct {
Raw asn1.RawContent
}
type attribute struct {
Type asn1.ObjectIdentifier
Value asn1.RawValue `asn1:"set"`
}
type issuerAndSerial struct {
IssuerName asn1.RawValue
SerialNumber *big.Int
}
// MessageDigestMismatchError is returned when the signer data digest does not
// match the computed digest for the contained content
type MessageDigestMismatchError struct {
ExpectedDigest []byte
ActualDigest []byte
}
func (err *MessageDigestMismatchError) Error() string {
return fmt.Sprintf("pkcs7: Message digest mismatch\n\tExpected: %X\n\tActual : %X", err.ExpectedDigest, err.ActualDigest)
}
type signerInfo struct {
Version int `asn1:"default:1"`
IssuerAndSerialNumber issuerAndSerial
DigestAlgorithm pkix.AlgorithmIdentifier
AuthenticatedAttributes []attribute `asn1:"optional,tag:0"`
DigestEncryptionAlgorithm pkix.AlgorithmIdentifier
EncryptedDigest []byte
UnauthenticatedAttributes []attribute `asn1:"optional,tag:1"`
}
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 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
}
var (
oidDigestAlgorithmSHA1 = asn1.ObjectIdentifier{1, 3, 14, 3, 2, 26}
oidSignatureSHA1WithRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 5}
)
func getCertFromCertsByIssuerAndSerial(certs []*x509.Certificate, ias issuerAndSerial) *x509.Certificate {
for _, cert := range certs {
if isCertMatchForIssuerAndSerial(cert, ias) {
return cert
}
}
return nil
}
// GetOnlySigner returns an x509.Certificate for the first signer of the signed
// data payload. If there are more or less than one signer, nil is returned
func (p7 *PKCS7) GetOnlySigner() *x509.Certificate {
if len(p7.Signers) != 1 {
return nil
}
signer := p7.Signers[0]
return getCertFromCertsByIssuerAndSerial(p7.Certificates, signer.IssuerAndSerialNumber)
}
// ErrUnsupportedAlgorithm tells you when our quick dev assumptions have failed
var ErrUnsupportedAlgorithm = errors.New("pkcs7: cannot decrypt data: only RSA, DES, DES-EDE3, AES-256-CBC and AES-128-GCM supported")
func isCertMatchForIssuerAndSerial(cert *x509.Certificate, ias issuerAndSerial) bool {
return cert.SerialNumber.Cmp(ias.SerialNumber) == 0 && bytes.Compare(cert.RawIssuer, ias.IssuerName.FullBytes) == 0
}
func unmarshalAttribute(attrs []attribute, attributeType asn1.ObjectIdentifier, out interface{}) error {
for _, attr := range attrs {
if attr.Type.Equal(attributeType) {
_, err := asn1.Unmarshal(attr.Value.Bytes, out)
return err
}
}
return errors.New("pkcs7: attribute type not in attributes")
}
// UnmarshalSignedAttribute decodes a single attribute from the signer info
func (p7 *PKCS7) UnmarshalSignedAttribute(attributeType asn1.ObjectIdentifier, out interface{}) error {
sd, ok := p7.raw.(signedData)
if !ok {
return errors.New("pkcs7: payload is not signedData content")
}
if len(sd.SignerInfos) < 1 {
return errors.New("pkcs7: payload has no signers")
}
attributes := sd.SignerInfos[0].AuthenticatedAttributes
return unmarshalAttribute(attributes, attributeType, out)
}
// SignedData is an opaque data structure for creating signed data payloads
type SignedData struct {
sd signedData
certs []*x509.Certificate
messageDigest []byte
}
// Attribute represents a key value pair attribute. Value must be marshalable byte
// `encoding/asn1`
type Attribute struct {
Type asn1.ObjectIdentifier
Value interface{}
}
// SignerInfoConfig are optional values to include when adding a signer
type SignerInfoConfig struct {
ExtraSignedAttributes []Attribute
}
// newSignedData initializes a SignedData with content
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},
}
digAlg := pkix.AlgorithmIdentifier{
Algorithm: oidDigestAlgorithmSHA1,
}
h := crypto.SHA1.New()
h.Write(data)
md := h.Sum(nil)
sd := signedData{
ContentInfo: ci,
Version: 1,
DigestAlgorithmIdentifiers: []pkix.AlgorithmIdentifier{digAlg},
}
return &SignedData{sd: sd, messageDigest: md}, nil
}
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) forMarshaling() ([]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
}
// addSigner signs attributes about the content and adds certificate to payload
func (sd *SignedData) addSigner(cert *x509.Certificate, pkey crypto.PrivateKey, config SignerInfoConfig) error {
attrs := &attributes{}
attrs.Add(oidAttributeContentType, sd.sd.ContentInfo.ContentType)
attrs.Add(oidAttributeMessageDigest, sd.messageDigest)
attrs.Add(oidAttributeSigningTime, time.Now())
for _, attr := range config.ExtraSignedAttributes {
attrs.Add(attr.Type, attr.Value)
}
finalAttrs, err := attrs.forMarshaling()
if err != nil {
return err
}
signature, err := signAttributes(finalAttrs, pkey, crypto.SHA1)
if err != nil {
return err
}
ias, err := cert2issuerAndSerial(cert)
if err != nil {
return err
}
signer := signerInfo{
AuthenticatedAttributes: finalAttrs,
DigestAlgorithm: pkix.AlgorithmIdentifier{Algorithm: oidDigestAlgorithmSHA1},
DigestEncryptionAlgorithm: pkix.AlgorithmIdentifier{Algorithm: oidSignatureSHA1WithRSA},
IssuerAndSerialNumber: ias,
EncryptedDigest: signature,
Version: 1,
}
// create signature of signed attributes
sd.certs = append(sd.certs, cert)
sd.sd.SignerInfos = append(sd.sd.SignerInfos, signer)
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}
}
// 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)
}
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, hash crypto.Hash) ([]byte, error) {
attrBytes, err := marshalAttributes(attrs)
if err != nil {
return nil, err
}
h := hash.New()
h.Write(attrBytes)
hashed := h.Sum(nil)
switch priv := pkey.(type) {
case *rsa.PrivateKey:
return rsa.SignPKCS1v15(rand.Reader, priv, crypto.SHA1, hashed)
}
return nil, ErrUnsupportedAlgorithm
}
// 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
}

189
pkcs7_test.go Normal file
View file

@ -0,0 +1,189 @@
// SPDX-FileCopyrightText: 2022-2023 The go-mail Authors
//
// SPDX-License-Identifier: MIT
package mail
import (
"crypto"
"crypto/rand"
"crypto/rsa"
"crypto/x509"
"crypto/x509/pkix"
"encoding/pem"
"fmt"
"io/ioutil"
"math/big"
"os"
"os/exec"
"testing"
"time"
)
// TestSign_E2E tests S/MIME singing as e2e
func TestSign_E2E(t *testing.T) {
cert, err := createTestCertificate()
if err != nil {
t.Fatal(err)
}
content := []byte("Hello World")
for _, testDetach := range []bool{false, true} {
toBeSigned, err := newSignedData(content)
if err != nil {
t.Fatalf("Cannot initialize signed data: %s", err)
}
if err := toBeSigned.addSigner(cert.Certificate, cert.PrivateKey, SignerInfoConfig{}); err != nil {
t.Fatalf("Cannot add signer: %s", err)
}
if testDetach {
t.Log("Testing detached signature")
toBeSigned.detach()
} else {
t.Log("Testing attached signature")
}
signed, err := toBeSigned.finish()
if err != nil {
t.Fatalf("Cannot finish signing data: %s", err)
}
if err := pem.Encode(os.Stdout, &pem.Block{Type: "PKCS7", Bytes: signed}); err != nil {
t.Fatalf("Cannot write signed data: %s", err)
}
}
}
func TestOpenSSLVerifyDetachedSignature(t *testing.T) {
rootCert, err := createTestCertificateByIssuer("PKCS7 Test Root CA", nil)
if err != nil {
t.Fatalf("Cannot generate root cert: %s", err)
}
signerCert, err := createTestCertificateByIssuer("PKCS7 Test Signer Cert", rootCert)
if err != nil {
t.Fatalf("Cannot generate signer cert: %s", err)
}
content := []byte("Hello World")
toBeSigned, err := newSignedData(content)
if err != nil {
t.Fatalf("Cannot initialize signed data: %s", err)
}
if err := toBeSigned.addSigner(signerCert.Certificate, signerCert.PrivateKey, SignerInfoConfig{}); err != nil {
t.Fatalf("Cannot add signer: %s", err)
}
toBeSigned.detach()
signed, err := toBeSigned.finish()
if err != nil {
t.Fatalf("Cannot finish signing data: %s", err)
}
// write the root cert to a temp file
tmpRootCertFile, err := ioutil.TempFile("", "pkcs7TestRootCA")
if err != nil {
t.Fatal(err)
}
defer os.Remove(tmpRootCertFile.Name()) // clean up
fd, err := os.OpenFile(tmpRootCertFile.Name(), os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0755)
if err != nil {
t.Fatal(err)
}
pem.Encode(fd, &pem.Block{Type: "CERTIFICATE", Bytes: rootCert.Certificate.Raw})
fd.Close()
// write the signature to a temp file
tmpSignatureFile, err := ioutil.TempFile("", "pkcs7Signature")
if err != nil {
t.Fatal(err)
}
defer os.Remove(tmpSignatureFile.Name()) // clean up
ioutil.WriteFile(tmpSignatureFile.Name(), signed, 0755)
// write the content to a temp file
tmpContentFile, err := ioutil.TempFile("", "pkcs7Content")
if err != nil {
t.Fatal(err)
}
defer os.Remove(tmpContentFile.Name()) // clean up
ioutil.WriteFile(tmpContentFile.Name(), content, 0755)
// call openssl to verify the signature on the content using the root
opensslCMD := exec.Command("openssl", "smime", "-verify",
"-in", tmpSignatureFile.Name(), "-inform", "DER",
"-content", tmpContentFile.Name(),
"-CAfile", tmpRootCertFile.Name())
out, err := opensslCMD.Output()
t.Logf("%s", out)
if err != nil {
t.Fatalf("openssl command failed with %s", err)
}
}
type certKeyPair struct {
Certificate *x509.Certificate
PrivateKey *rsa.PrivateKey
}
func createTestCertificate() (*certKeyPair, error) {
signer, err := createTestCertificateByIssuer("Eddard Stark", nil)
if err != nil {
return nil, err
}
fmt.Println("Created root cert")
if err := pem.Encode(os.Stdout, &pem.Block{Type: "CERTIFICATE", Bytes: signer.Certificate.Raw}); err != nil {
return nil, err
}
pair, err := createTestCertificateByIssuer("Jon Snow", signer)
if err != nil {
return nil, err
}
fmt.Println("Created signer cert")
if err := pem.Encode(os.Stdout, &pem.Block{Type: "CERTIFICATE", Bytes: pair.Certificate.Raw}); err != nil {
return nil, err
}
return pair, nil
}
func createTestCertificateByIssuer(name string, issuer *certKeyPair) (*certKeyPair, error) {
priv, err := rsa.GenerateKey(rand.Reader, 1024)
if err != nil {
return nil, err
}
serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 32)
serialNumber, err := rand.Int(rand.Reader, serialNumberLimit)
if err != nil {
return nil, err
}
template := x509.Certificate{
SerialNumber: serialNumber,
SignatureAlgorithm: x509.SHA256WithRSA,
Subject: pkix.Name{
CommonName: name,
Organization: []string{"Acme Co"},
},
NotBefore: time.Now(),
NotAfter: time.Now().AddDate(1, 0, 0),
KeyUsage: x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
ExtKeyUsage: []x509.ExtKeyUsage{x509.ExtKeyUsageEmailProtection},
}
var issuerCert *x509.Certificate
var issuerKey crypto.PrivateKey
if issuer != nil {
issuerCert = issuer.Certificate
issuerKey = issuer.PrivateKey
} else {
template.IsCA = true
template.KeyUsage |= x509.KeyUsageCertSign
issuerCert = &template
issuerKey = priv
}
cert, err := x509.CreateCertificate(rand.Reader, &template, issuerCert, priv.Public(), issuerKey)
if err != nil {
return nil, err
}
leaf, err := x509.ParseCertificate(cert)
if err != nil {
return nil, err
}
return &certKeyPair{
Certificate: leaf,
PrivateKey: priv,
}, nil
}