From 84f326092afa341fd1828b6e3aec4c54a7c25351 Mon Sep 17 00:00:00 2001
From: Chevdor <chevdor@gmail.com>
Date: Mon, 30 May 2022 12:06:37 +0200
Subject: [PATCH] Allow user overriding the Parachain Pallet Id

fix #45
---
 README.md                                     | 16 ++++++-----
 README_src.adoc                               |  2 ++
 .../Cargo.toml                                |  2 +-
 .../src/lib.rs                                | 28 +++++++++++++++++--
 4 files changed, 37 insertions(+), 11 deletions(-)

diff --git a/README.md b/README.md
index a322835..e747698 100644
--- a/README.md
+++ b/README.md
@@ -63,7 +63,7 @@ MacOS Homebrew users can use:
 
 ### Command: --help
 
-    subwasm 0.17.0
+    subwasm 0.17.1
     chevdor <chevdor@gmail.com>:Wilfried Kopp <wilfried@parity.io
     `subwasm` allows fetching, parsing and calling some methods on WASM runtimes of Substrate based
     chains
@@ -92,7 +92,7 @@ MacOS Homebrew users can use:
 
 ### Command: get
 
-    subwasm-get 0.17.0
+    subwasm-get 0.17.1
     chevdor <chevdor@gmail.com>:Wilfried Kopp <wilfried@parity.io
     Get/Download the runtime wasm from a running node through rpc
 
@@ -122,7 +122,7 @@ MacOS Homebrew users can use:
 
 ### Command: info
 
-    subwasm-info 0.17.0
+    subwasm-info 0.17.1
     chevdor <chevdor@gmail.com>:Wilfried Kopp <wilfried@parity.io
     The `info` command returns summarized information about a runtime
 
@@ -145,9 +145,11 @@ MacOS Homebrew users can use:
         -j, --json             Output as json
         -V, --version          Print version information
 
+By default, the ID for the Parachain pallet is expected to be `0x01`. This default behavior can be overriden by setting the `PARACHAIN_PALLET_ID_ENV` to the ID of your parachain pallet.
+
 ### Command: meta
 
-    subwasm-metadata 0.17.0
+    subwasm-metadata 0.17.1
     chevdor <chevdor@gmail.com>:Wilfried Kopp <wilfried@parity.io
     Returns the metadata as a json object. You may also use the "meta" alias
 
@@ -176,7 +178,7 @@ MacOS Homebrew users can use:
 
 ### Command: diff
 
-    subwasm-diff 0.17.0
+    subwasm-diff 0.17.1
     chevdor <chevdor@gmail.com>:Wilfried Kopp <wilfried@parity.io
     Compare 2 runtimes
 
@@ -200,7 +202,7 @@ MacOS Homebrew users can use:
 
 ### Command: compress
 
-    subwasm-compress 0.17.0
+    subwasm-compress 0.17.1
     chevdor <chevdor@gmail.com>:Wilfried Kopp <wilfried@parity.io
     Compress a given runtime wasm file. You will get an error if you try compressing a runtime that is
     already compressed
@@ -219,7 +221,7 @@ MacOS Homebrew users can use:
 
 ### Command: decompress
 
-    subwasm-decompress 0.17.0
+    subwasm-decompress 0.17.1
     chevdor <chevdor@gmail.com>:Wilfried Kopp <wilfried@parity.io
     Decompress a given runtime wasm file. You may pass a runtime that is uncompressed already. In that
     case, you will get the same content as output. This is useful if you want to decompress "no matter
diff --git a/README_src.adoc b/README_src.adoc
index 1ab9fbe..12cbc2d 100644
--- a/README_src.adoc
+++ b/README_src.adoc
@@ -85,6 +85,8 @@ include::doc/usage_get.adoc[]
 include::doc/usage_info.adoc[]
 ----
 
+NOTE: By default, the ID for the Parachain pallet is expected to be `0x01`. This default behavior can be overriden by setting the `PARACHAIN_PALLET_ID_ENV` to the ID of your parachain pallet.
+
 === Command: meta
 ----
 include::doc/usage_meta.adoc[]
diff --git a/libs/substrate-runtime-proposal-hash/Cargo.toml b/libs/substrate-runtime-proposal-hash/Cargo.toml
index 67b448c..1cbd275 100644
--- a/libs/substrate-runtime-proposal-hash/Cargo.toml
+++ b/libs/substrate-runtime-proposal-hash/Cargo.toml
@@ -13,7 +13,7 @@ version = "0.17.0"
 blake2 = "0.10"
 codec = {version = "2.3", package = "parity-scale-codec"}
 frame-metadata = {version = "14", package = "frame-metadata", features = ["v12", "v13", "v14", "std"]}
-hex = "0.4"
+hex = "0.4.3"
 sc-executor = "0.9"
 sp-core = "3.0"
 sp-io = "3.0"
diff --git a/libs/substrate-runtime-proposal-hash/src/lib.rs b/libs/substrate-runtime-proposal-hash/src/lib.rs
index e2263f0..b5f9b1c 100644
--- a/libs/substrate-runtime-proposal-hash/src/lib.rs
+++ b/libs/substrate-runtime-proposal-hash/src/lib.rs
@@ -1,8 +1,10 @@
 use blake2::digest::{Update, VariableOutput};
 use blake2::Blake2bVar;
 use codec::Encode;
+use hex::FromHex;
 use sp_core::Hasher;
 use sp_runtime::traits::BlakeTwo256;
+use std::env;
 
 /// Expected size of the hash
 pub const SIZE: usize = 32;
@@ -14,7 +16,7 @@ type Prefix = (u8, u8);
 
 /// The PREFIX is prepended to the data before hashing
 pub const PREFIX_SYSTEM_SETCODE: Prefix = (0x00, 0x03);
-pub const PREFIX_PARACHAINSYSTEM_AUTHORIZE_UPGRADE: Prefix = (0x01, 0x03);
+const PARACHAIN_PALLET_ID_ENV: &str = "PARACHAIN_PALLET_ID";
 
 /// This struct is a container for whatever we calculated.
 #[derive(Debug)]
@@ -59,8 +61,12 @@ pub fn get_system_setcode(wasm_blob: &[u8]) -> CalllHash {
 }
 
 pub fn get_parachainsystem_authorize_upgrade(wasm_blob: &[u8]) -> CalllHash {
+	let s = env::var(PARACHAIN_PALLET_ID_ENV).unwrap_or_else(|_| String::from("0x01")).replace("0x", "");
+	let decoded = <[u8; 1]>::from_hex(s).expect("Decoding failed");
+	let parachain_pallet_id = *decoded.first().expect("Failure while fecthing the Parachain Pallet ID");
+	let prefix_parachainsystem_authorize_upgrade: Prefix = (parachain_pallet_id, 0x03);
 	let code_hash = BlakeTwo256::hash(wasm_blob);
-	get_call_hash(PREFIX_PARACHAINSYSTEM_AUTHORIZE_UPGRADE, code_hash.as_bytes())
+	get_call_hash(prefix_parachainsystem_authorize_upgrade, code_hash.as_bytes())
 }
 
 fn get_call_hash(prefix: Prefix, wasm_blob: &[u8]) -> CalllHash {
@@ -72,8 +78,9 @@ fn get_call_hash(prefix: Prefix, wasm_blob: &[u8]) -> CalllHash {
 }
 
 #[cfg(test)]
-mod tests {
+mod prop_hash_tests {
 	use super::*;
+	use std::env;
 
 	#[test]
 	fn test_proposal_hash() {
@@ -99,6 +106,7 @@ mod tests {
 
 	#[test]
 	fn test_parachain_upgrade() {
+		env::set_var(PARACHAIN_PALLET_ID_ENV, "0x01");
 		assert_eq!(
 			get_parachainsystem_authorize_upgrade(&[
 				0x00, 0x61, 0x73, 0x6d, 0x01, 0x00, 0x00, 0x00, 0x01, 0x97, 0x03, 0x39, 0x60, 0x03, 0x7f, 0x7f
@@ -110,6 +118,20 @@ mod tests {
 		);
 	}
 
+	#[test]
+	fn test_custom_parachain_upgrade() {
+		env::set_var(PARACHAIN_PALLET_ID_ENV, "0x32");
+		assert_eq!(
+			get_parachainsystem_authorize_upgrade(&[
+				0x00, 0x61, 0x73, 0x6d, 0x01, 0x00, 0x00, 0x00, 0x01, 0x97, 0x03, 0x39, 0x60, 0x03, 0x7f, 0x7f
+			]),
+			[
+				29, 53, 127, 234, 110, 75, 67, 238, 243, 171, 65, 93, 187, 246, 0, 84, 166, 88, 161, 205, 95, 62, 135,
+				99, 121, 139, 154, 39, 207, 121, 98, 87
+			]
+		);
+	}
+
 	#[test]
 	fn test_hash_length() {
 		assert_eq!(32, get_proposal_hash(&[0]).len());