From 0f1db4c616eb39a560258da8e362233e952196ea Mon Sep 17 00:00:00 2001
From: Michiel de Jong <michiel@ripple.com>
Date: Thu, 26 Oct 2017 15:16:56 +0200
Subject: [PATCH] feat: forwarded payments

---
 .../0003-interledger-protocol.md              | 31 +++++++++++++++++--
 asn1/InterledgerPacket.asn                    |  8 +++--
 asn1/InterledgerProtocol.asn                  | 12 +++++++
 3 files changed, 46 insertions(+), 5 deletions(-)

diff --git a/0003-interledger-protocol/0003-interledger-protocol.md b/0003-interledger-protocol/0003-interledger-protocol.md
index fa14b398..471f478d 100644
--- a/0003-interledger-protocol/0003-interledger-protocol.md
+++ b/0003-interledger-protocol/0003-interledger-protocol.md
@@ -1,6 +1,6 @@
 ---
 title: The Interledger Protocol (ILP)
-draft: 6
+draft: 7
 ---
 # Interledger Protocol (ILP)
 
@@ -152,7 +152,12 @@ See below for the [ILP Error Format](#ilp-error-format) and [ILP Error Codes](#i
 
 ### ILP Payment Packet Format
 
-Here is a summary of the fields in the ILP payment packet format:
+There are two types of payment packets: delivered and forwarded. A delivered payment specifies the amount that should arrive at the destination, a forwarded payment doesn't.
+Note that forwarded payments are still experimental, and their definition may change or get deprecated at any time.
+
+Here is a summary of the fields in the delivered and forwarded ILP payment packet formats:
+
+#### Delivered Payment Packet
 
 | Field | Type | Short Description |
 |:--|:--|:--|
@@ -163,7 +168,7 @@ Here is a summary of the fields in the ILP payment packet format:
 | data | OCTET STRING | Transport layer data attached to the payment |
 | extensions | Length Determinant | Always `0`
 
-#### Example
+Here's an example:
 
 | Type | Length, 8+(1+14)+(1+3)+1=28 | Amount (123,000,000) ... |
 |:--|:--|:--|
@@ -182,6 +187,26 @@ Here is a summary of the fields in the ILP payment packet format:
 |:--|:--|:--|:--|
 | 98 | 3      | 4 16 65 | 0          |
 
+### Forwarded Payment Packet (experimental)
+
+| Field | Type | Short Description |
+|:--|:--|:--|
+| type | UInt8 | Always `10`, indicates that this ILP packet is an ILP Forwarded Payment Packet (type 10) |
+| length | Length Determinant | Indicates how many bytes the rest of the packet has |
+| account | Address | Address corresponding to the destination account |
+| data | OCTET STRING | Transport layer data attached to the payment |
+| extensions | Length Determinant | Always `0`
+
+Example:
+
+| Type | Length, (1+14)+(1+3)+1=20 | Length | Address ... ('g.us.nexus.bo')
+|:--|:--|:--|:--|
+| 10   |  20                       | 14     | 103 46 117 115 46 110 101 120 117 115 46 98 111 |
+
+| ... Address ('b') | length | data    | extensions |
+|:--|:--|:--|:--|
+| 98 | 3      | 4 16 65 | 0          |
+
 
 Let's look more closely at the three important fields: `amount`, `address`, and `data`.
 
diff --git a/asn1/InterledgerPacket.asn b/asn1/InterledgerPacket.asn
index e66564c4..25ee0e51 100644
--- a/asn1/InterledgerPacket.asn
+++ b/asn1/InterledgerPacket.asn
@@ -9,7 +9,9 @@ IMPORTS
     FROM GenericTypes
 
     InterledgerProtocolPaymentData,
-    InterledgerProtocolErrorData
+    ForwardedPaymentData, -- experimental
+    InterledgerProtocolErrorData,
+    InterledgerProtocolFulfillmentData
     FROM InterledgerProtocol
 
     QuoteLiquidityRequestData,
@@ -34,7 +36,9 @@ PacketSet PACKET ::= {
     {5 QuoteBySourceAmountResponseData} |
     {6 QuoteByDestinationAmountRequestData} |
     {7 QuoteByDestinationAmountResponseData} |
-    {8 InterledgerProtocolErrorData}
+    {8 InterledgerProtocolErrorData} |
+    {9 InterledgerProtocolFulfillmentData } |
+    {10 ForwardedPaymentData} -- experimental
 }
 
 InterledgerPacket ::= SEQUENCE {
diff --git a/asn1/InterledgerProtocol.asn b/asn1/InterledgerProtocol.asn
index b2b476ed..7cd08a16 100644
--- a/asn1/InterledgerProtocol.asn
+++ b/asn1/InterledgerProtocol.asn
@@ -12,6 +12,18 @@ IMPORTS
     FROM InterledgerTypes
 ;
 
+-- the following packet type is experimental and may still change
+ForwardedPaymentData ::= SEQUENCE {
+    -- Destination ILP Address
+    account Address,
+    -- Information for recipient (transport layer information)
+    data OCTET STRING (SIZE (0..32767)),
+    -- Enable ASN.1 Extensibility
+    extensions SEQUENCE {
+        ...
+    }
+}
+
 InterledgerProtocolPaymentData ::= SEQUENCE {
     -- Amount which must be received at the destination
     amount UInt64,