diff options
Diffstat (limited to 'framing/framing.go')
| -rw-r--r-- | framing/framing.go | 21 |
1 files changed, 8 insertions, 13 deletions
diff --git a/framing/framing.go b/framing/framing.go index c57189d..5518b9f 100644 --- a/framing/framing.go +++ b/framing/framing.go @@ -29,21 +29,20 @@ // Package framing implements the obfs4 link framing and cryptography. // // The Encoder/Decoder shared secret format is: -// uint8_t[32] NaCl SecretBox key -// uint8_t[24] NaCl Nonce prefix +// uint8_t[32] NaCl secretbox key +// uint8_t[16] NaCl Nonce prefix // uint8_t[16] SipHash-2-4 key (used to obfsucate length) // // The frame format is: // uint16_t length (obfsucated, big endian) -// NaCl SecretBox (Poly1305/XSalsa20) containing: -// uint8_t[16] tag (Part of the SecretBox construct) +// NaCl secretbox (Poly1305/XSalsa20) containing: +// uint8_t[16] tag (Part of the secretbox construct) // uint8_t[] payload // -// The length field is length of the NaCl SecretBox XORed with the truncated -// SipHash-2-4 digest of the previous SecretBox concatenated with the nonce -// used to seal the current SecretBox. +// The length field is length of the NaCl secretbox XORed with the truncated +// SipHash-2-4 digest of the nonce used to seal/unseal the current secretbox. // -// The NaCl SecretBox (Poly1305/XSalsa20) nonce format is: +// The NaCl secretbox (Poly1305/XSalsa20) nonce format is: // uint8_t[24] prefix (Fixed) // uint64_t counter (Big endian) // @@ -101,7 +100,7 @@ var ErrAgain = errors.New("framing: More data needed to decode") // Error returned when Decoder.Decode() failes to authenticate a frame. var ErrTagMismatch = errors.New("framing: Poly1305 tag mismatch") -// Error returned when the NaCl SecretBox nonce's counter wraps (FATAL). +// Error returned when the NaCl secretbox nonce's counter wraps (FATAL). var ErrNonceCounterWrapped = errors.New("framing: Nonce counter wrapped") // InvalidPayloadLengthError is the error returned when Encoder.Encode() @@ -203,9 +202,6 @@ func (encoder *Encoder) Encode(frame, payload []byte) (n int, err error) { length ^= binary.BigEndian.Uint16(lengthMask) binary.BigEndian.PutUint16(frame[:2], length) - // Prepare the next obfsucator. - encoder.sip.Write(box[lengthLength:]) - // Return the frame. return len(box), nil } @@ -293,7 +289,6 @@ func (decoder *Decoder) Decode(data []byte, frames *bytes.Buffer) (int, error) { if !ok { return 0, ErrTagMismatch } - decoder.sip.Write(box[:n]) // Clean up and prepare for the next frame. decoder.nextLength = 0 |