Report errors during handshake stage (#1091)

Co-authored-by: Neil Alexander <neilalexander@users.noreply.github.com>
This commit is contained in:
Neil 2023-11-04 17:57:04 +00:00 committed by GitHub
parent ae997a5acb
commit ddb75700a0
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
3 changed files with 21 additions and 17 deletions

View File

@ -546,8 +546,9 @@ func (l *links) handler(linkType linkType, options linkOptions, conn net.Conn) e
}
meta = version_metadata{}
base := version_getBaseMetadata()
if !meta.decode(conn, options.password) {
return conn.Close()
if err := meta.decode(conn, options.password); err != nil {
_ = conn.Close()
return err
}
if !meta.check() {
return fmt.Errorf("remote node incompatible version (local %s, remote %s)",

View File

@ -87,22 +87,22 @@ func (m *version_metadata) encode(privateKey ed25519.PrivateKey, password []byte
}
// Decodes version metadata from its wire format into the struct.
func (m *version_metadata) decode(r io.Reader, password []byte) bool {
func (m *version_metadata) decode(r io.Reader, password []byte) error {
bh := [6]byte{}
if _, err := io.ReadFull(r, bh[:]); err != nil {
return false
return err
}
meta := [4]byte{'m', 'e', 't', 'a'}
if !bytes.Equal(bh[:4], meta[:]) {
return false
return fmt.Errorf("invalid handshake preamble")
}
bs := make([]byte, binary.BigEndian.Uint16(bh[4:6]))
hl := binary.BigEndian.Uint16(bh[4:6])
if hl < ed25519.SignatureSize {
return fmt.Errorf("invalid handshake length")
}
bs := make([]byte, hl)
if _, err := io.ReadFull(r, bs); err != nil {
return false
}
if len(bs) < ed25519.SignatureSize {
return false
return err
}
sig := bs[len(bs)-ed25519.SignatureSize:]
bs = bs[:len(bs)-ed25519.SignatureSize]
@ -132,14 +132,17 @@ func (m *version_metadata) decode(r io.Reader, password []byte) bool {
hasher, err := blake2b.New512(password)
if err != nil {
return false
return fmt.Errorf("invalid password supplied")
}
n, err := hasher.Write(m.publicKey)
if err != nil || n != ed25519.PublicKeySize {
return false
return fmt.Errorf("failed to generate hash")
}
hash := hasher.Sum(nil)
return ed25519.Verify(m.publicKey, hash, sig)
if !ed25519.Verify(m.publicKey, hash, sig) {
return fmt.Errorf("password is incorrect")
}
return nil
}
// Checks that the "meta" bytes and the version numbers are the expected values.

View File

@ -34,7 +34,7 @@ func TestVersionPasswordAuth(t *testing.T) {
}
var decoded version_metadata
if allowed := decoded.decode(bytes.NewBuffer(encoded), tt.password2); allowed != tt.allowed {
if allowed := decoded.decode(bytes.NewBuffer(encoded), tt.password2) == nil; allowed != tt.allowed {
t.Fatalf("Permutation %q -> %q should have been %v but was %v", tt.password1, tt.password2, tt.allowed, allowed)
}
}
@ -67,8 +67,8 @@ func TestVersionRoundtrip(t *testing.T) {
}
encoded := bytes.NewBuffer(meta)
decoded := &version_metadata{}
if !decoded.decode(encoded, password) {
t.Fatalf("failed to decode")
if err := decoded.decode(encoded, password); err != nil {
t.Fatalf("failed to decode: %s", err)
}
if !reflect.DeepEqual(test, decoded) {
t.Fatalf("round-trip failed\nwant: %+v\n got: %+v", test, decoded)