From d28e6393eda0d3c1755d1e088611bf2e5da3534e Mon Sep 17 00:00:00 2001
From: zzz <zzz@mail.i2p>
Date: Fri, 1 May 2020 11:15:12 +0000
Subject: [PATCH] Streaming and prop. 144 minor updates
---
.../144-ecies-x25519-aead-ratchet.rst | 36 ++++++++++---------
i2p2www/spec/streaming.rst | 17 ++++++---
2 files changed, 31 insertions(+), 22 deletions(-)
diff --git a/i2p2www/spec/proposals/144-ecies-x25519-aead-ratchet.rst b/i2p2www/spec/proposals/144-ecies-x25519-aead-ratchet.rst
index 9e89cf4cf..f367ad5a6 100644
--- a/i2p2www/spec/proposals/144-ecies-x25519-aead-ratchet.rst
+++ b/i2p2www/spec/proposals/144-ecies-x25519-aead-ratchet.rst
@@ -5,7 +5,7 @@ ECIES-X25519-AEAD-Ratchet
:author: zzz, chisana, orignal
:created: 2018-11-22
:thread: http://zzz.i2p/topics/2639
- :lastupdated: 2020-04-28
+ :lastupdated: 2020-05-01
:status: Open
:target: 0.9.46
:implementedin: 0.9.46
@@ -2134,7 +2134,7 @@ Inputs:
Generated:
2) input_key_material = SESSTAG_CONSTANT
- Must be unique for this chain (generated from chain key),
+ Must be unique for this tag set (generated from chain key),
so that the sequence isn't predictable, since session tags
go out on the wire in plaintext.
@@ -3265,17 +3265,18 @@ ElGamal block:
- 2 byte tag count
- 1024 bytes of tags (32 typical)
- 4 byte payload size
- - 16 byte I2NP header
- - 15 byte msg cert, id, exp.
- - 33 byte Garlic deliv. inst.
- - 15 byte clove cert, id, exp.
- 32 byte hash of payload
- 1 byte flags
- - 8 byte (average) padding to 16 bytes
- 1150 total
+ - 1 byte clove count
+ - 33 byte Garlic deliv. inst.
+ - 16 byte I2NP header
+ - 15 byte clove cert, id, exp.
+ - 15 byte msg cert, id, exp.
+ - 0 byte padding assuming 1936 byte message
+ 1143 total
Total:
- 1664 bytes
+ 1657 bytes
{% endhighlight %}
Existing session messages, same each direction:
@@ -3287,19 +3288,20 @@ AES block:
- 32 byte session tag
- 2 byte tag count
- 4 byte payload size
+ - 32 byte hash of payload
+ - 1 byte flags
+ - 1 byte clove count
+ - 33 byte Garlic deliv. inst.
- 16 byte I2NP header
- 15 byte msg cert, id, exp.
- - 33 byte Garlic deliv. inst.
- 15 byte clove cert, id, exp.
- - 32 byte hash of payload
- - 1 byte flags
- - 8 byte (average) padding to 16 bytes
- 158 total
+ - 0 byte padding assuming 1936 byte message
+ 151 total
{% endhighlight %}
{% highlight lang='text' %}
Four message total (two each direction)
- 3644 bytes overhead
+ 3616 bytes overhead
{% endhighlight %}
@@ -3374,7 +3376,7 @@ Handshake only:
.. raw:: html
{% highlight lang='text' %}
-ElGamal: 1664 + 1664 = 3328 bytes
+ElGamal: 1657 + 1657 = 3314 bytes
Ratchet: 148 _ 117 = 265 bytes
92% (approx. 12x) reduction compared to ElGamal/AES+SessionTags
{% endhighlight %}
@@ -3384,7 +3386,7 @@ Long-term total (ignoring handshakes):
.. raw:: html
{% highlight lang='text' %}
-ElGamal: 158 + 32 byte tag sent previously = 190 bytes
+ElGamal: 151 + 32 byte tag sent previously = 183 bytes
Ratchet: 69 bytes
64% (approx. 3x) reduction compared to ElGamal/AES+SessionTags
{% endhighlight %}
diff --git a/i2p2www/spec/streaming.rst b/i2p2www/spec/streaming.rst
index 91ac75178..2b15b4b0a 100644
--- a/i2p2www/spec/streaming.rst
+++ b/i2p2www/spec/streaming.rst
@@ -3,8 +3,8 @@ Streaming Library Specification
===============================
.. meta::
:category: Protocols
- :lastupdated: February 2019
- :accuratefor: 0.9.39
+ :lastupdated: May 2020
+ :accuratefor: 0.9.46
.. contents::
@@ -59,7 +59,12 @@ Protocol Specification
Packet Format
-------------
-The format of a single packet in the streaming protocol is:
+The format of a single packet in the streaming protocol is shown below.
+The minimum header size, without NACKs or option data, is 22 bytes.
+
+There is no length field in the streaming protocol.
+Framing is provided by the lower layers - I2CP and I2NP.
+
.. raw:: html
@@ -69,15 +74,17 @@ The format of a single packet in the streaming protocol is:
+----+----+----+----+----+----+----+----+
| sequence Num | ack Through |
+----+----+----+----+----+----+----+----+
- | nc | NACKs ...
+ | nc | nc*4 bytes of NACKs (optional)
+----+----+----+----+----+----+----+----+
| rd | flags | opt size| opt data
+----+----+----+----+----+----+----+----+
- ... |
+ ... (optional, see below) |
+----+----+----+----+----+----+----+----+
| payload ...
+----+----+----+-//
+
+
sendStreamId :: 4 byte `Integer`
Random number selected by the packet recipient before sending
the first SYN reply packet and constant for the life of the
--
GitLab