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keys.go
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keys.go
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// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package openpgp
import (
goerrors "errors"
"io"
"time"
"github.com/ProtonMail/go-crypto/openpgp/armor"
"github.com/ProtonMail/go-crypto/openpgp/errors"
"github.com/ProtonMail/go-crypto/openpgp/packet"
)
// PublicKeyType is the armor type for a PGP public key.
var PublicKeyType = "PGP PUBLIC KEY BLOCK"
// PrivateKeyType is the armor type for a PGP private key.
var PrivateKeyType = "PGP PRIVATE KEY BLOCK"
// An Entity represents the components of an OpenPGP key: a primary public key
// (which must be a signing key), one or more identities claimed by that key,
// and zero or more subkeys, which may be encryption keys.
type Entity struct {
PrimaryKey *packet.PublicKey
PrivateKey *packet.PrivateKey
Identities map[string]*Identity // indexed by Identity.Name
Revocations []*packet.Signature
Subkeys []Subkey
}
// An Identity represents an identity claimed by an Entity and zero or more
// assertions by other entities about that claim.
type Identity struct {
Name string // by convention, has the form "Full Name (comment) <email@example.com>"
UserId *packet.UserId
SelfSignature *packet.Signature
Revocations []*packet.Signature
Signatures []*packet.Signature // all (potentially unverified) self-signatures, revocations, and third-party signatures
}
// A Subkey is an additional public key in an Entity. Subkeys can be used for
// encryption.
type Subkey struct {
PublicKey *packet.PublicKey
PrivateKey *packet.PrivateKey
Sig *packet.Signature
Revocations []*packet.Signature
}
// A Key identifies a specific public key in an Entity. This is either the
// Entity's primary key or a subkey.
type Key struct {
Entity *Entity
PublicKey *packet.PublicKey
PrivateKey *packet.PrivateKey
SelfSignature *packet.Signature
Revocations []*packet.Signature
}
// A KeyRing provides access to public and private keys.
type KeyRing interface {
// KeysById returns the set of keys that have the given key id.
KeysById(id uint64) []Key
// KeysByIdAndUsage returns the set of keys with the given id
// that also meet the key usage given by requiredUsage.
// The requiredUsage is expressed as the bitwise-OR of
// packet.KeyFlag* values.
KeysByIdUsage(id uint64, requiredUsage byte) []Key
// DecryptionKeys returns all private keys that are valid for
// decryption.
DecryptionKeys() []Key
}
// PrimaryIdentity returns an Identity, preferring non-revoked identities,
// identities marked as primary, or the latest-created identity, in that order.
func (e *Entity) PrimaryIdentity() *Identity {
var primaryIdentity *Identity
for _, ident := range e.Identities {
if shouldPreferIdentity(primaryIdentity, ident) {
primaryIdentity = ident
}
}
return primaryIdentity
}
func shouldPreferIdentity(existingId, potentialNewId *Identity) bool {
if existingId == nil {
return true
}
if len(existingId.Revocations) > len(potentialNewId.Revocations) {
return true
}
if len(existingId.Revocations) < len(potentialNewId.Revocations) {
return false
}
if existingId.SelfSignature == nil {
return true
}
if existingId.SelfSignature.IsPrimaryId != nil && *existingId.SelfSignature.IsPrimaryId &&
!(potentialNewId.SelfSignature.IsPrimaryId != nil && *potentialNewId.SelfSignature.IsPrimaryId) {
return false
}
if !(existingId.SelfSignature.IsPrimaryId != nil && *existingId.SelfSignature.IsPrimaryId) &&
potentialNewId.SelfSignature.IsPrimaryId != nil && *potentialNewId.SelfSignature.IsPrimaryId {
return true
}
return potentialNewId.SelfSignature.CreationTime.After(existingId.SelfSignature.CreationTime)
}
// EncryptionKey returns the best candidate Key for encrypting a message to the
// given Entity.
func (e *Entity) EncryptionKey(now time.Time) (Key, bool) {
// Fail to find any encryption key if the...
i := e.PrimaryIdentity()
if e.PrimaryKey.KeyExpired(i.SelfSignature, now) || // primary key has expired
i.SelfSignature == nil || // user ID has no self-signature
i.SelfSignature.SigExpired(now) || // user ID self-signature has expired
e.Revoked(now) || // primary key has been revoked
i.Revoked(now) { // user ID has been revoked
return Key{}, false
}
// Iterate the keys to find the newest, unexpired one
candidateSubkey := -1
var maxTime time.Time
for i, subkey := range e.Subkeys {
if subkey.Sig.FlagsValid &&
subkey.Sig.FlagEncryptCommunications &&
subkey.PublicKey.PubKeyAlgo.CanEncrypt() &&
!subkey.PublicKey.KeyExpired(subkey.Sig, now) &&
!subkey.Sig.SigExpired(now) &&
!subkey.Revoked(now) &&
(maxTime.IsZero() || subkey.Sig.CreationTime.After(maxTime)) {
candidateSubkey = i
maxTime = subkey.Sig.CreationTime
}
}
if candidateSubkey != -1 {
subkey := e.Subkeys[candidateSubkey]
return Key{e, subkey.PublicKey, subkey.PrivateKey, subkey.Sig, subkey.Revocations}, true
}
// If we don't have any subkeys for encryption and the primary key
// is marked as OK to encrypt with, then we can use it.
if i.SelfSignature.FlagsValid && i.SelfSignature.FlagEncryptCommunications &&
e.PrimaryKey.PubKeyAlgo.CanEncrypt() {
return Key{e, e.PrimaryKey, e.PrivateKey, i.SelfSignature, e.Revocations}, true
}
return Key{}, false
}
// CertificationKey return the best candidate Key for certifying a key with this
// Entity.
func (e *Entity) CertificationKey(now time.Time) (Key, bool) {
return e.CertificationKeyById(now, 0)
}
// CertificationKeyById return the Key for key certification with this
// Entity and keyID.
func (e *Entity) CertificationKeyById(now time.Time, id uint64) (Key, bool) {
return e.signingKeyByIdUsage(now, id, packet.KeyFlagCertify)
}
// SigningKey return the best candidate Key for signing a message with this
// Entity.
func (e *Entity) SigningKey(now time.Time) (Key, bool) {
return e.SigningKeyById(now, 0)
}
// SigningKeyById return the Key for signing a message with this
// Entity and keyID.
func (e *Entity) SigningKeyById(now time.Time, id uint64) (Key, bool) {
return e.signingKeyByIdUsage(now, id, packet.KeyFlagSign)
}
func (e *Entity) signingKeyByIdUsage(now time.Time, id uint64, flags int) (Key, bool) {
// Fail to find any signing key if the...
i := e.PrimaryIdentity()
if e.PrimaryKey.KeyExpired(i.SelfSignature, now) || // primary key has expired
i.SelfSignature == nil || // user ID has no self-signature
i.SelfSignature.SigExpired(now) || // user ID self-signature has expired
e.Revoked(now) || // primary key has been revoked
i.Revoked(now) { // user ID has been revoked
return Key{}, false
}
// Iterate the keys to find the newest, unexpired one
candidateSubkey := -1
var maxTime time.Time
for idx, subkey := range e.Subkeys {
if subkey.Sig.FlagsValid &&
(flags&packet.KeyFlagCertify == 0 || subkey.Sig.FlagCertify) &&
(flags&packet.KeyFlagSign == 0 || subkey.Sig.FlagSign) &&
subkey.PublicKey.PubKeyAlgo.CanSign() &&
!subkey.PublicKey.KeyExpired(subkey.Sig, now) &&
!subkey.Sig.SigExpired(now) &&
!subkey.Revoked(now) &&
(maxTime.IsZero() || subkey.Sig.CreationTime.After(maxTime)) &&
(id == 0 || subkey.PublicKey.KeyId == id) {
candidateSubkey = idx
maxTime = subkey.Sig.CreationTime
}
}
if candidateSubkey != -1 {
subkey := e.Subkeys[candidateSubkey]
return Key{e, subkey.PublicKey, subkey.PrivateKey, subkey.Sig, subkey.Revocations}, true
}
// If we don't have any subkeys for signing and the primary key
// is marked as OK to sign with, then we can use it.
if i.SelfSignature.FlagsValid &&
(flags&packet.KeyFlagCertify == 0 || i.SelfSignature.FlagCertify) &&
(flags&packet.KeyFlagSign == 0 || i.SelfSignature.FlagSign) &&
e.PrimaryKey.PubKeyAlgo.CanSign() &&
(id == 0 || e.PrimaryKey.KeyId == id) {
return Key{e, e.PrimaryKey, e.PrivateKey, i.SelfSignature, e.Revocations}, true
}
// No keys with a valid Signing Flag or no keys matched the id passed in
return Key{}, false
}
func revoked(revocations []*packet.Signature, now time.Time) bool {
for _, revocation := range revocations {
if revocation.RevocationReason != nil && *revocation.RevocationReason == packet.KeyCompromised {
// If the key is compromised, the key is considered revoked even before the revocation date.
return true
}
if !revocation.SigExpired(now) {
return true
}
}
return false
}
// Revoked returns whether the entity has any direct key revocation signatures.
// Note that third-party revocation signatures are not supported.
// Note also that Identity and Subkey revocation should be checked separately.
func (e *Entity) Revoked(now time.Time) bool {
return revoked(e.Revocations, now)
}
// EncryptPrivateKeys encrypts all non-encrypted keys in the entity with the same key
// derived from the provided passphrase. Public keys and dummy keys are ignored,
// and don't cause an error to be returned.
func (e *Entity) EncryptPrivateKeys(passphrase []byte, config *packet.Config) error {
var keysToEncrypt []*packet.PrivateKey
// Add entity private key to encrypt.
if e.PrivateKey != nil && !e.PrivateKey.Dummy() && !e.PrivateKey.Encrypted {
keysToEncrypt = append(keysToEncrypt, e.PrivateKey)
}
// Add subkeys to encrypt.
for _, sub := range e.Subkeys {
if sub.PrivateKey != nil && !sub.PrivateKey.Dummy() && !sub.PrivateKey.Encrypted {
keysToEncrypt = append(keysToEncrypt, sub.PrivateKey)
}
}
return packet.EncryptPrivateKeys(keysToEncrypt, passphrase, config)
}
// DecryptPrivateKeys decrypts all encrypted keys in the entitiy with the given passphrase.
// Avoids recomputation of similar s2k key derivations. Public keys and dummy keys are ignored,
// and don't cause an error to be returned.
func (e *Entity) DecryptPrivateKeys(passphrase []byte) error {
var keysToDecrypt []*packet.PrivateKey
// Add entity private key to decrypt.
if e.PrivateKey != nil && !e.PrivateKey.Dummy() && e.PrivateKey.Encrypted {
keysToDecrypt = append(keysToDecrypt, e.PrivateKey)
}
// Add subkeys to decrypt.
for _, sub := range e.Subkeys {
if sub.PrivateKey != nil && !sub.PrivateKey.Dummy() && sub.PrivateKey.Encrypted {
keysToDecrypt = append(keysToDecrypt, sub.PrivateKey)
}
}
return packet.DecryptPrivateKeys(keysToDecrypt, passphrase)
}
// Revoked returns whether the identity has been revoked by a self-signature.
// Note that third-party revocation signatures are not supported.
func (i *Identity) Revoked(now time.Time) bool {
return revoked(i.Revocations, now)
}
// Revoked returns whether the subkey has been revoked by a self-signature.
// Note that third-party revocation signatures are not supported.
func (s *Subkey) Revoked(now time.Time) bool {
return revoked(s.Revocations, now)
}
// Revoked returns whether the key or subkey has been revoked by a self-signature.
// Note that third-party revocation signatures are not supported.
// Note also that Identity revocation should be checked separately.
// Normally, it's not necessary to call this function, except on keys returned by
// KeysById or KeysByIdUsage.
func (key *Key) Revoked(now time.Time) bool {
return revoked(key.Revocations, now)
}
// An EntityList contains one or more Entities.
type EntityList []*Entity
// KeysById returns the set of keys that have the given key id.
func (el EntityList) KeysById(id uint64) (keys []Key) {
for _, e := range el {
if e.PrimaryKey.KeyId == id {
ident := e.PrimaryIdentity()
selfSig := ident.SelfSignature
keys = append(keys, Key{e, e.PrimaryKey, e.PrivateKey, selfSig, e.Revocations})
}
for _, subKey := range e.Subkeys {
if subKey.PublicKey.KeyId == id {
keys = append(keys, Key{e, subKey.PublicKey, subKey.PrivateKey, subKey.Sig, subKey.Revocations})
}
}
}
return
}
// KeysByIdAndUsage returns the set of keys with the given id that also meet
// the key usage given by requiredUsage. The requiredUsage is expressed as
// the bitwise-OR of packet.KeyFlag* values.
func (el EntityList) KeysByIdUsage(id uint64, requiredUsage byte) (keys []Key) {
for _, key := range el.KeysById(id) {
if requiredUsage != 0 {
if key.SelfSignature == nil || !key.SelfSignature.FlagsValid {
continue
}
var usage byte
if key.SelfSignature.FlagCertify {
usage |= packet.KeyFlagCertify
}
if key.SelfSignature.FlagSign {
usage |= packet.KeyFlagSign
}
if key.SelfSignature.FlagEncryptCommunications {
usage |= packet.KeyFlagEncryptCommunications
}
if key.SelfSignature.FlagEncryptStorage {
usage |= packet.KeyFlagEncryptStorage
}
if usage&requiredUsage != requiredUsage {
continue
}
}
keys = append(keys, key)
}
return
}
// DecryptionKeys returns all private keys that are valid for decryption.
func (el EntityList) DecryptionKeys() (keys []Key) {
for _, e := range el {
for _, subKey := range e.Subkeys {
if subKey.PrivateKey != nil && subKey.Sig.FlagsValid && (subKey.Sig.FlagEncryptStorage || subKey.Sig.FlagEncryptCommunications) {
keys = append(keys, Key{e, subKey.PublicKey, subKey.PrivateKey, subKey.Sig, subKey.Revocations})
}
}
}
return
}
// ReadArmoredKeyRing reads one or more public/private keys from an armor keyring file.
func ReadArmoredKeyRing(r io.Reader) (EntityList, error) {
block, err := armor.Decode(r)
if err == io.EOF {
return nil, errors.InvalidArgumentError("no armored data found")
}
if err != nil {
return nil, err
}
if block.Type != PublicKeyType && block.Type != PrivateKeyType {
return nil, errors.InvalidArgumentError("expected public or private key block, got: " + block.Type)
}
return ReadKeyRing(block.Body)
}
// ReadKeyRing reads one or more public/private keys. Unsupported keys are
// ignored as long as at least a single valid key is found.
func ReadKeyRing(r io.Reader) (el EntityList, err error) {
packets := packet.NewReader(r)
var lastUnsupportedError error
for {
var e *Entity
e, err = ReadEntity(packets)
if err != nil {
// TODO: warn about skipped unsupported/unreadable keys
if _, ok := err.(errors.UnsupportedError); ok {
lastUnsupportedError = err
err = readToNextPublicKey(packets)
} else if _, ok := err.(errors.StructuralError); ok {
// Skip unreadable, badly-formatted keys
lastUnsupportedError = err
err = readToNextPublicKey(packets)
}
if err == io.EOF {
err = nil
break
}
if err != nil {
el = nil
break
}
} else {
el = append(el, e)
}
}
if len(el) == 0 && err == nil {
err = lastUnsupportedError
}
return
}
// readToNextPublicKey reads packets until the start of the entity and leaves
// the first packet of the new entity in the Reader.
func readToNextPublicKey(packets *packet.Reader) (err error) {
var p packet.Packet
for {
p, err = packets.Next()
if err == io.EOF {
return
} else if err != nil {
if _, ok := err.(errors.UnsupportedError); ok {
err = nil
continue
}
return
}
if pk, ok := p.(*packet.PublicKey); ok && !pk.IsSubkey {
packets.Unread(p)
return
}
}
}
// ReadEntity reads an entity (public key, identities, subkeys etc) from the
// given Reader.
func ReadEntity(packets *packet.Reader) (*Entity, error) {
e := new(Entity)
e.Identities = make(map[string]*Identity)
p, err := packets.Next()
if err != nil {
return nil, err
}
var ok bool
if e.PrimaryKey, ok = p.(*packet.PublicKey); !ok {
if e.PrivateKey, ok = p.(*packet.PrivateKey); !ok {
packets.Unread(p)
return nil, errors.StructuralError("first packet was not a public/private key")
}
e.PrimaryKey = &e.PrivateKey.PublicKey
}
if !e.PrimaryKey.PubKeyAlgo.CanSign() {
return nil, errors.StructuralError("primary key cannot be used for signatures")
}
var revocations []*packet.Signature
EachPacket:
for {
p, err := packets.Next()
if err == io.EOF {
break
} else if err != nil {
return nil, err
}
switch pkt := p.(type) {
case *packet.UserId:
if err := addUserID(e, packets, pkt); err != nil {
return nil, err
}
case *packet.Signature:
if pkt.SigType == packet.SigTypeKeyRevocation {
revocations = append(revocations, pkt)
} else if pkt.SigType == packet.SigTypeDirectSignature {
// TODO: RFC4880 5.2.1 permits signatures
// directly on keys (eg. to bind additional
// revocation keys).
}
// Else, ignoring the signature as it does not follow anything
// we would know to attach it to.
case *packet.PrivateKey:
if pkt.IsSubkey == false {
packets.Unread(p)
break EachPacket
}
err = addSubkey(e, packets, &pkt.PublicKey, pkt)
if err != nil {
return nil, err
}
case *packet.PublicKey:
if pkt.IsSubkey == false {
packets.Unread(p)
break EachPacket
}
err = addSubkey(e, packets, pkt, nil)
if err != nil {
return nil, err
}
default:
// we ignore unknown packets
}
}
if len(e.Identities) == 0 {
return nil, errors.StructuralError("entity without any identities")
}
for _, revocation := range revocations {
err = e.PrimaryKey.VerifyRevocationSignature(revocation)
if err == nil {
e.Revocations = append(e.Revocations, revocation)
} else {
// TODO: RFC 4880 5.2.3.15 defines revocation keys.
return nil, errors.StructuralError("revocation signature signed by alternate key")
}
}
return e, nil
}
func addUserID(e *Entity, packets *packet.Reader, pkt *packet.UserId) error {
// Make a new Identity object, that we might wind up throwing away.
// We'll only add it if we get a valid self-signature over this
// userID.
identity := new(Identity)
identity.Name = pkt.Id
identity.UserId = pkt
for {
p, err := packets.Next()
if err == io.EOF {
break
} else if err != nil {
return err
}
sig, ok := p.(*packet.Signature)
if !ok {
packets.Unread(p)
break
}
if sig.SigType != packet.SigTypeGenericCert &&
sig.SigType != packet.SigTypePersonaCert &&
sig.SigType != packet.SigTypeCasualCert &&
sig.SigType != packet.SigTypePositiveCert &&
sig.SigType != packet.SigTypeCertificationRevocation {
return errors.StructuralError("user ID signature with wrong type")
}
if sig.CheckKeyIdOrFingerprint(e.PrimaryKey) {
if err = e.PrimaryKey.VerifyUserIdSignature(pkt.Id, e.PrimaryKey, sig); err != nil {
return errors.StructuralError("user ID self-signature invalid: " + err.Error())
}
if sig.SigType == packet.SigTypeCertificationRevocation {
identity.Revocations = append(identity.Revocations, sig)
} else if identity.SelfSignature == nil || sig.CreationTime.After(identity.SelfSignature.CreationTime) {
identity.SelfSignature = sig
}
identity.Signatures = append(identity.Signatures, sig)
e.Identities[pkt.Id] = identity
} else {
identity.Signatures = append(identity.Signatures, sig)
}
}
return nil
}
func addSubkey(e *Entity, packets *packet.Reader, pub *packet.PublicKey, priv *packet.PrivateKey) error {
var subKey Subkey
subKey.PublicKey = pub
subKey.PrivateKey = priv
for {
p, err := packets.Next()
if err == io.EOF {
break
} else if err != nil {
return errors.StructuralError("subkey signature invalid: " + err.Error())
}
sig, ok := p.(*packet.Signature)
if !ok {
packets.Unread(p)
break
}
if sig.SigType != packet.SigTypeSubkeyBinding && sig.SigType != packet.SigTypeSubkeyRevocation {
return errors.StructuralError("subkey signature with wrong type")
}
if err := e.PrimaryKey.VerifyKeySignature(subKey.PublicKey, sig); err != nil {
return errors.StructuralError("subkey signature invalid: " + err.Error())
}
switch sig.SigType {
case packet.SigTypeSubkeyRevocation:
subKey.Revocations = append(subKey.Revocations, sig)
case packet.SigTypeSubkeyBinding:
if subKey.Sig == nil || sig.CreationTime.After(subKey.Sig.CreationTime) {
subKey.Sig = sig
}
}
}
if subKey.Sig == nil {
return errors.StructuralError("subkey packet not followed by signature")
}
e.Subkeys = append(e.Subkeys, subKey)
return nil
}
// SerializePrivate serializes an Entity, including private key material, but
// excluding signatures from other entities, to the given Writer.
// Identities and subkeys are re-signed in case they changed since NewEntry.
// If config is nil, sensible defaults will be used.
func (e *Entity) SerializePrivate(w io.Writer, config *packet.Config) (err error) {
if e.PrivateKey.Dummy() {
return errors.ErrDummyPrivateKey("dummy private key cannot re-sign identities")
}
return e.serializePrivate(w, config, true)
}
// SerializePrivateWithoutSigning serializes an Entity, including private key
// material, but excluding signatures from other entities, to the given Writer.
// Self-signatures of identities and subkeys are not re-signed. This is useful
// when serializing GNU dummy keys, among other things.
// If config is nil, sensible defaults will be used.
func (e *Entity) SerializePrivateWithoutSigning(w io.Writer, config *packet.Config) (err error) {
return e.serializePrivate(w, config, false)
}
func (e *Entity) serializePrivate(w io.Writer, config *packet.Config, reSign bool) (err error) {
if e.PrivateKey == nil {
return goerrors.New("openpgp: private key is missing")
}
err = e.PrivateKey.Serialize(w)
if err != nil {
return
}
for _, revocation := range e.Revocations {
err := revocation.Serialize(w)
if err != nil {
return err
}
}
for _, ident := range e.Identities {
err = ident.UserId.Serialize(w)
if err != nil {
return
}
if reSign {
if ident.SelfSignature == nil {
return goerrors.New("openpgp: can't re-sign identity without valid self-signature")
}
err = ident.SelfSignature.SignUserId(ident.UserId.Id, e.PrimaryKey, e.PrivateKey, config)
if err != nil {
return
}
}
for _, sig := range ident.Signatures {
err = sig.Serialize(w)
if err != nil {
return err
}
}
}
for _, subkey := range e.Subkeys {
err = subkey.PrivateKey.Serialize(w)
if err != nil {
return
}
if reSign {
err = subkey.Sig.SignKey(subkey.PublicKey, e.PrivateKey, config)
if err != nil {
return
}
if subkey.Sig.EmbeddedSignature != nil {
err = subkey.Sig.EmbeddedSignature.CrossSignKey(subkey.PublicKey, e.PrimaryKey,
subkey.PrivateKey, config)
if err != nil {
return
}
}
}
for _, revocation := range subkey.Revocations {
err := revocation.Serialize(w)
if err != nil {
return err
}
}
err = subkey.Sig.Serialize(w)
if err != nil {
return
}
}
return nil
}
// Serialize writes the public part of the given Entity to w, including
// signatures from other entities. No private key material will be output.
func (e *Entity) Serialize(w io.Writer) error {
err := e.PrimaryKey.Serialize(w)
if err != nil {
return err
}
for _, revocation := range e.Revocations {
err := revocation.Serialize(w)
if err != nil {
return err
}
}
for _, ident := range e.Identities {
err = ident.UserId.Serialize(w)
if err != nil {
return err
}
for _, sig := range ident.Signatures {
err = sig.Serialize(w)
if err != nil {
return err
}
}
}
for _, subkey := range e.Subkeys {
err = subkey.PublicKey.Serialize(w)
if err != nil {
return err
}
for _, revocation := range subkey.Revocations {
err := revocation.Serialize(w)
if err != nil {
return err
}
}
err = subkey.Sig.Serialize(w)
if err != nil {
return err
}
}
return nil
}
// SignIdentity adds a signature to e, from signer, attesting that identity is
// associated with e. The provided identity must already be an element of
// e.Identities and the private key of signer must have been decrypted if
// necessary.
// If config is nil, sensible defaults will be used.
func (e *Entity) SignIdentity(identity string, signer *Entity, config *packet.Config) error {
certificationKey, ok := signer.CertificationKey(config.Now())
if !ok {
return errors.InvalidArgumentError("no valid certification key found")
}
if certificationKey.PrivateKey.Encrypted {
return errors.InvalidArgumentError("signing Entity's private key must be decrypted")
}
ident, ok := e.Identities[identity]
if !ok {
return errors.InvalidArgumentError("given identity string not found in Entity")
}
sig := createSignaturePacket(certificationKey.PublicKey, packet.SigTypeGenericCert, config)
signingUserID := config.SigningUserId()
if signingUserID != "" {
if _, ok := signer.Identities[signingUserID]; !ok {
return errors.InvalidArgumentError("signer identity string not found in signer Entity")
}
sig.SignerUserId = &signingUserID
}
if err := sig.SignUserId(identity, e.PrimaryKey, certificationKey.PrivateKey, config); err != nil {
return err
}
ident.Signatures = append(ident.Signatures, sig)
return nil
}
// RevokeKey generates a key revocation signature (packet.SigTypeKeyRevocation) with the
// specified reason code and text (RFC4880 section-5.2.3.23).
// If config is nil, sensible defaults will be used.
func (e *Entity) RevokeKey(reason packet.ReasonForRevocation, reasonText string, config *packet.Config) error {
revSig := createSignaturePacket(e.PrimaryKey, packet.SigTypeKeyRevocation, config)
revSig.RevocationReason = &reason
revSig.RevocationReasonText = reasonText
if err := revSig.RevokeKey(e.PrimaryKey, e.PrivateKey, config); err != nil {
return err
}
e.Revocations = append(e.Revocations, revSig)
return nil
}
// RevokeSubkey generates a subkey revocation signature (packet.SigTypeSubkeyRevocation) for
// a subkey with the specified reason code and text (RFC4880 section-5.2.3.23).
// If config is nil, sensible defaults will be used.
func (e *Entity) RevokeSubkey(sk *Subkey, reason packet.ReasonForRevocation, reasonText string, config *packet.Config) error {
if err := e.PrimaryKey.VerifyKeySignature(sk.PublicKey, sk.Sig); err != nil {
return errors.InvalidArgumentError("given subkey is not associated with this key")
}
revSig := createSignaturePacket(e.PrimaryKey, packet.SigTypeSubkeyRevocation, config)
revSig.RevocationReason = &reason
revSig.RevocationReasonText = reasonText
if err := revSig.RevokeSubkey(sk.PublicKey, e.PrivateKey, config); err != nil {
return err
}
sk.Revocations = append(sk.Revocations, revSig)
return nil
}