// VerifySignatures verifies that the Action contains valid signatures from
// known investigators. It does not verify permissions.
func (a Action) VerifySignatures(keyring io.Reader) (err error) {
defer func() {
if e := recover(); e != nil {
err = fmt.Errorf("VerifySignatures() -> %v", e)
}
}()
astr, err := a.String()
if err != nil {
return errors.New("Failed to stringify action")
}
for _, sig := range a.PGPSignatures {
valid, _, err := pgp.Verify(astr, sig, keyring)
if err != nil {
return errors.New("Failed to verify PGP Signature")
}
if !valid {
return errors.New("Invalid PGP Signature")
}
}
return
}
// Validates signatures stored in the manifest against keys in keyring, returns
// the number of valid signature matches
func (m *ManifestResponse) VerifySignatures(keyring io.Reader) (validcnt int, err error) {
var sigs []string
// Copy signatures out of the response, and clear them as we do not
// include them as part of the JSON document in validation
sigs = make([]string, len(m.Signatures))
copy(sigs, m.Signatures)
m.Signatures = m.Signatures[:0]
mcopy := *m
// Also zero the loader name as it is not included in the signature
mcopy.LoaderName = ""
buf, err := json.Marshal(mcopy)
if err != nil {
return validcnt, err
}
// Create a copy of the keyring we can use during validation of each
// signature. We don't want to use the keyring directly as it is
// backed by a buffer and will be drained after verification of the
// first signature.
keycopy, err := ioutil.ReadAll(keyring)
if err != nil {
return validcnt, err
}
for _, x := range sigs {
keyreader := bytes.NewBuffer(keycopy)
valid, _, err := pgp.Verify(string(buf), x, keyreader)
if err != nil {
return validcnt, err
}
if valid {
validcnt++
}
}
return
}