1 files changed, 106 insertions, 0 deletions
diff --git a/vendor/github.com/pion/dtls/v2/pkg/protocol/handshake/message_server_hello.go b/vendor/github.com/pion/dtls/v2/pkg/protocol/handshake/message_server_hello.go
new file mode 100644
index 0000000..c4b181f
--- /dev/null
+++ b/vendor/github.com/pion/dtls/v2/pkg/protocol/handshake/message_server_hello.go
@@ -0,0 +1,106 @@
+package handshake
+
+import (
+	"encoding/binary"
+
+	"github.com/pion/dtls/v2/pkg/protocol"
+	"github.com/pion/dtls/v2/pkg/protocol/extension"
+)
+
+// MessageServerHello is sent in response to a ClientHello
+// message when it was able to find an acceptable set of algorithms.
+// If it cannot find such a match, it will respond with a handshake
+// failure alert.
+//
+// https://tools.ietf.org/html/rfc5246#section-7.4.1.3
+type MessageServerHello struct {
+	Version protocol.Version
+	Random  Random
+
+	CipherSuiteID     *uint16
+	CompressionMethod *protocol.CompressionMethod
+	Extensions        []extension.Extension
+}
+
+const messageServerHelloVariableWidthStart = 2 + RandomLength
+
+// Type returns the Handshake Type
+func (m MessageServerHello) Type() Type {
+	return TypeServerHello
+}
+
+// Marshal encodes the Handshake
+func (m *MessageServerHello) Marshal() ([]byte, error) {
+	if m.CipherSuiteID == nil {
+		return nil, errCipherSuiteUnset
+	} else if m.CompressionMethod == nil {
+		return nil, errCompressionMethodUnset
+	}
+
+	out := make([]byte, messageServerHelloVariableWidthStart)
+	out[0] = m.Version.Major
+	out[1] = m.Version.Minor
+
+	rand := m.Random.MarshalFixed()
+	copy(out[2:], rand[:])
+
+	out = append(out, 0x00) // SessionID
+
+	out = append(out, []byte{0x00, 0x00}...)
+	binary.BigEndian.PutUint16(out[len(out)-2:], *m.CipherSuiteID)
+
+	out = append(out, byte(m.CompressionMethod.ID))
+
+	extensions, err := extension.Marshal(m.Extensions)
+	if err != nil {
+		return nil, err
+	}
+
+	return append(out, extensions...), nil
+}
+
+// Unmarshal populates the message from encoded data
+func (m *MessageServerHello) Unmarshal(data []byte) error {
+	if len(data) < 2+RandomLength {
+		return errBufferTooSmall
+	}
+
+	m.Version.Major = data[0]
+	m.Version.Minor = data[1]
+
+	var random [RandomLength]byte
+	copy(random[:], data[2:])
+	m.Random.UnmarshalFixed(random)
+
+	currOffset := messageServerHelloVariableWidthStart
+	currOffset += int(data[currOffset]) + 1 // SessionID
+	if len(data) < (currOffset + 2) {
+		return errBufferTooSmall
+	}
+
+	m.CipherSuiteID = new(uint16)
+	*m.CipherSuiteID = binary.BigEndian.Uint16(data[currOffset:])
+	currOffset += 2
+
+	if len(data) < currOffset {
+		return errBufferTooSmall
+	}
+	if compressionMethod, ok := protocol.CompressionMethods()[protocol.CompressionMethodID(data[currOffset])]; ok {
+		m.CompressionMethod = compressionMethod
+		currOffset++
+	} else {
+		return errInvalidCompressionMethod
+	}
+
+	if len(data) <= currOffset {
+		m.Extensions = []extension.Extension{}
+		return nil
+	}
+
+	extensions, err := extension.Unmarshal(data[currOffset:])
+	if err != nil {
+		return err
+	}
+	m.Extensions = extensions
+	return nil
+}