From 44f59b0502547a9a8d74934dcb2424a39e9b783a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20H=C3=BCsers?= <aur@huesers.de>
Date: Sun, 9 Jun 2024 21:50:07 +0200
Subject: [PATCH] upgpkg: discord-electron 0.0.55-1: refactor, replace krisp
 patcher

* upstream release
* Slight refactor of package function and launcher script
* Replace Krisp patcher with more robust Python script
* Add support for DISCORD_USER_DATA_DIR env var
---
 discord-electron/.SRCINFO                 | 14 ++--
 discord-electron/PKGBUILD                 | 36 +++++-----
 discord-electron/discord-electron.install | 15 +++-
 discord-electron/discord-launcher.sh      | 16 ++---
 discord-electron/krisp-patcher.py         | 83 +++++++++++++++++++++++
 discord-electron/update-package.sh        | 57 ++++++++++++++++
 6 files changed, 186 insertions(+), 35 deletions(-)
 create mode 100644 discord-electron/krisp-patcher.py
 create mode 100755 discord-electron/update-package.sh

diff --git a/discord-electron/.SRCINFO b/discord-electron/.SRCINFO
index a25909c..c07b47d 100644
--- a/discord-electron/.SRCINFO
+++ b/discord-electron/.SRCINFO
@@ -1,6 +1,6 @@
 pkgbase = discord-electron
 	pkgdesc = Discord using system provided electron (v30) for increased security and performance
-	pkgver = 0.0.54
+	pkgver = 0.0.55
 	pkgrel = 1
 	url = https://discord.com
 	install = discord-electron.install
@@ -11,16 +11,20 @@ pkgbase = discord-electron
 	makedepends = python-html2text
 	depends = electron30
 	depends = libxss
+	depends = python
 	optdepends = libpulse: Pulseaudio support
 	optdepends = libappindicator-gtk3: Systray indicator support
 	optdepends = xdg-utils: Open files
-	optdepends = rizin: Allow patching Krisp support
+	optdepends = python-pyelftools: Required for Krisp patcher
+	optdepends = python-capstone: Required for Krisp patcher
 	provides = discord
 	conflicts = discord
 	options = !strip
-	source = https://dl.discordapp.net/apps/linux/0.0.54/discord-0.0.54.tar.gz
+	source = https://dl.discordapp.net/apps/linux/0.0.55/discord-0.0.55.tar.gz
 	source = discord-launcher.sh
-	sha512sums = ceb6265e846fafd27e3c2941f00f0a2d4e045abe5471a2691b070bedb330ef345edee838a706b27ff65ecce40aec46b1a1dd9c4bb9763dadaa907ec181c1a222
-	sha512sums = 9d00f9d2e05c2ba31c930c066f247954700bb0f96f2fc605e61c3973d7dacf962bf372659b71e05e5d8d4e152cc884bf12ec1fb5ecbfc4da55d22ab2591c4c40
+	source = krisp-patcher.py
+	sha512sums = c12365109cb4db94033fda101073d2a3d6af7bdc9728e025494ee8d44ebf5f27623861879ec38bb7dd88d40de7cddede268e0f5e44bfeb586fc12713a3758c5b
+	sha512sums = fc25a6ac9ca2881a94158ed972039a4dcc082db91a8ba072f2f896b65a788c9decb4456c71da977ac2976e72d081c6c66aa4bb27b5d58cf946dfea6086b0d557
+	sha512sums = 3c1021592fa856f3561072c76b5ee0b5a34a53bc230336e6d36827efb4866c9d801ef7abb24650d3a7210c61dd57f35e2812ae89226fc157cc8d9ffce032155f
 
 pkgname = discord-electron
diff --git a/discord-electron/PKGBUILD b/discord-electron/PKGBUILD
index 825a770..16c4084 100644
--- a/discord-electron/PKGBUILD
+++ b/discord-electron/PKGBUILD
@@ -1,6 +1,6 @@
 pkgname=discord-electron
 _pkgname=discord
-pkgver=0.0.54
+pkgver=0.0.55
 pkgrel=1
 _electronver=30
 _electronname="electron${_electronver}"
@@ -12,27 +12,27 @@ url='https://discord.com'
 license=('custom')
 options=('!strip')
 install="$pkgname.install"
-depends=("${_electronname}" 'libxss')
+depends=("${_electronname}" 'libxss' 'python')
 makedepends=('asar' 'curl' 'python-html2text')
 optdepends=(
 	'libpulse: Pulseaudio support'
 	'libappindicator-gtk3: Systray indicator support'
 	'xdg-utils: Open files'
-	'rizin: Allow patching Krisp support'
+	'python-pyelftools: Required for Krisp patcher'
+	'python-capstone: Required for Krisp patcher'
 )
 source=("https://dl.discordapp.net/apps/linux/${pkgver}/${_pkgname}-${pkgver}.tar.gz"
-	'discord-launcher.sh')
-sha512sums=('ceb6265e846fafd27e3c2941f00f0a2d4e045abe5471a2691b070bedb330ef345edee838a706b27ff65ecce40aec46b1a1dd9c4bb9763dadaa907ec181c1a222'
-            '9d00f9d2e05c2ba31c930c066f247954700bb0f96f2fc605e61c3973d7dacf962bf372659b71e05e5d8d4e152cc884bf12ec1fb5ecbfc4da55d22ab2591c4c40')
-
-_krisp_b2sum='c4e49b1a0be64cacd23474c5e474130084755f2de36af01686ce94c6eceea67426b6d6aa81889a418f9d08476476e99d63479b6131d1f7eaef987ecf4d779cf9'
+	'discord-launcher.sh'
+	'krisp-patcher.py') # original: https://github.com/sersorrel/sys/blob/main/hm/discord/krisp-patcher.py
+sha512sums=('c12365109cb4db94033fda101073d2a3d6af7bdc9728e025494ee8d44ebf5f27623861879ec38bb7dd88d40de7cddede268e0f5e44bfeb586fc12713a3758c5b'
+            'fc25a6ac9ca2881a94158ed972039a4dcc082db91a8ba072f2f896b65a788c9decb4456c71da977ac2976e72d081c6c66aa4bb27b5d58cf946dfea6086b0d557'
+            '3c1021592fa856f3561072c76b5ee0b5a34a53bc230336e6d36827efb4866c9d801ef7abb24650d3a7210c61dd57f35e2812ae89226fc157cc8d9ffce032155f')
 
 prepare() {
 	# prepare launcher script
 	sed -i -e "s|@PKGNAME@|${_pkgname}|g" \
 		-e "s|@PKGVER@|${pkgver}|g" \
 		-e "s|@ELECTRON@|${_electronname}|g" \
-		-e "s|@KRISPB2@|${_krisp_b2sum}|g" \
 		discord-launcher.sh
 
 	# fix the .desktop file
@@ -62,20 +62,22 @@ build() {
 
 package() {
 	# create necessary directories
-	install -d "${pkgdir}"/usr/{lib/$_pkgname,bin}
-	install -d "${pkgdir}"/usr/share/{pixmaps,applications,licenses/$_pkgname}
+	install -d "${pkgdir}"/usr/lib/$_pkgname
 
 	# copy relevant data
 	cp -r ${_pkgname^}/resources "${pkgdir}"/usr/lib/$_pkgname/
-	cp ${_pkgname^}/$_pkgname.png \
-		"${pkgdir}"/usr/share/pixmaps/$_pkgname.png
-	cp ${_pkgname^}/$_pkgname.desktop \
-		"${pkgdir}"/usr/share/applications/$_pkgname.desktop
+
+	# intall icon and desktop file
+	install -Dm 644 ${_pkgname^}/$_pkgname.png "${pkgdir}"/usr/share/pixmaps/$_pkgname.png
+	install -Dm 644 ${_pkgname^}/$_pkgname.desktop "${pkgdir}"/usr/share/applications/$_pkgname.desktop
 
 	# install the launch script
 	install -Dm 755 discord-launcher.sh "${pkgdir}"/usr/bin/$_pkgname
 
+	# install krisp patcher
+	install -Dm 644 krisp-patcher.py "${pkgdir}"/usr/lib/${_pkgname}/
+
 	# install licenses
-	install -Dm 644 LICENSE.md "${pkgdir}"/usr/share/licenses/$_pkgname/
-	install -Dm 644 OSS-LICENSES.md "${pkgdir}"/usr/share/licenses/$_pkgname/
+	install -Dm 644 LICENSE.md "${pkgdir}"/usr/share/licenses/$_pkgname/LICENSE.md
+	install -Dm 644 OSS-LICENSES.md "${pkgdir}"/usr/share/licenses/$_pkgname/OSS-LICENSES.md
 }
diff --git a/discord-electron/discord-electron.install b/discord-electron/discord-electron.install
index 193b455..fe95226 100644
--- a/discord-electron/discord-electron.install
+++ b/discord-electron/discord-electron.install
@@ -1,4 +1,13 @@
 post_upgrade() {
+	# return if old package version is greater than or equal to 0.0.55-1...
+	(( $(vercmp $2 '0.0.55-1') >= 0 )) && return
+
+	cat <<EOF
+==> Instead of using 'rizin' to patch Krisp support a patcher written in Python
+    is now used. Consider installing the necessary optional dependencies to use
+    this feature.
+EOF
+
 	# return if old package version is greater than or equal to 0.0.39-2...
 	(( $(vercmp $2 '0.0.39-2') >= 0 )) && return
 
@@ -26,9 +35,9 @@ EOF
 
 post_install() {
 	cat <<EOF
-==> For Krisp noise suppression support consider installing 'rizin' and
-    setting 'PATCH_KRISP=true' in '~/.config/discord.conf'. Restart your
-    Discord client afterwards to apply the patch.
+==> For Krisp noise suppression support consider installing the necessary optional
+    dependencies and setting 'PATCH_KRISP=true' in '~/.config/discord.conf'.
+    Restart your Discord client afterwards to apply the patch.
 ==> In case of performance problems consider setting additional flags
     in '~/.config/discord-flags.conf'.
 EOF
diff --git a/discord-electron/discord-launcher.sh b/discord-electron/discord-launcher.sh
index c63b91c..e0604e2 100644
--- a/discord-electron/discord-launcher.sh
+++ b/discord-electron/discord-launcher.sh
@@ -1,22 +1,18 @@
 #!/usr/bin/env bash
 
-set -eo pipefail
+set -euo pipefail
 
 declare -a flags
-
+declare -l PATCH_KRISP
 
 [[ -r "${XDG_CONFIG_HOME:-$HOME/.config}/@PKGNAME@.conf" ]] && source "${XDG_CONFIG_HOME:-$HOME/.config}/@PKGNAME@.conf"
 
 flags_file="${XDG_CONFIG_HOME:-$HOME/.config}/@PKGNAME@-flags.conf"
-krisp_bin="${XDG_CONFIG_HOME:-$HOME/.config}/@PKGNAME@/@PKGVER@/modules/@PKGNAME@_krisp/@PKGNAME@_krisp.node"
-krisp_b2=@KRISPB2@
+krisp_bin="${DISCORD_USER_DATA_DIR:-${XDG_CONFIG_HOME:-$HOME/.config}/@PKGNAME@}/@PKGVER@/modules/@PKGNAME@_krisp/@PKGNAME@_krisp.node"
 
-if hash rizin &> /dev/null && [[ "${PATCH_KRISP}" == true ]]; then
+if [[ "${PATCH_KRISP}" == true ]] && [[ -w "${krisp_bin}" ]] && python -c "import capstone; import elftools" &> /dev/null; then
 	# Patch Krisp binary to ignore signature check
-	if [[ -w "${krisp_bin}" && $(b2sum "${krisp_bin}" | head -c 128) == $krisp_b2 ]]; then
-		addr=$(rz-find -x '4881ec00010000' "${krisp_bin}" | head -n1)
-		rizin -q -w -c "s $addr + 0x30 ; wao nop" "${krisp_bin}" &> /dev/null
-	fi
+	python /usr/lib/@PKGNAME@/krisp-patcher.py "${krisp_bin}"
 fi
 
 if [[ -r "${flags_file}" ]]; then
@@ -33,7 +29,7 @@ for line in "${MAPFILE[@]}"; do
 	fi
 done
 
-unset flags_file krisp_bin krisp_b2
+unset flags_file krisp_bin
 
 
 exec /usr/lib/@ELECTRON@/electron \
diff --git a/discord-electron/krisp-patcher.py b/discord-electron/krisp-patcher.py
new file mode 100644
index 0000000..5597290
--- /dev/null
+++ b/discord-electron/krisp-patcher.py
@@ -0,0 +1,83 @@
+import sys
+import shutil
+
+from elftools.elf.elffile import ELFFile
+from capstone import *
+from capstone.x86 import *
+
+if len(sys.argv) < 2:
+    print(f"Usage: {sys.argv[0]} [path to discord_krisp.node]")
+    # "Unix programs generally use 2 for command line syntax errors and 1 for all other kind of errors."
+    sys.exit(2)
+
+executable = sys.argv[1]
+
+elf = ELFFile(open(executable, "rb"))
+symtab = elf.get_section_by_name('.symtab')
+
+krisp_initialize_address = symtab.get_symbol_by_name("_ZN7discord15KrispInitializeEv")[0].entry.st_value
+isSignedByDiscord_address = symtab.get_symbol_by_name("_ZN7discord4util17IsSignedByDiscordERKNSt4__Cr12basic_stringIcNS1_11char_traitsIcEENS1_9allocatorIcEEEE")[0].entry.st_value
+
+text = elf.get_section_by_name('.text')
+text_start = text['sh_addr']
+text_start_file = text['sh_offset']
+# This seems to always be zero (.text starts at the right offset in the file). Do it just in case?
+address_to_file = text_start_file - text_start
+
+# Done with the ELF now.
+# elf.close()
+
+krisp_initialize_offset = krisp_initialize_address - address_to_file
+isSignedByDiscord_offset = krisp_initialize_address - address_to_file
+
+f = open(executable, "rb")
+f.seek(krisp_initialize_offset)
+krisp_initialize = f.read(64)
+f.close()
+
+# States
+found_issigned_by_discord_call = False
+found_issigned_by_discord_test = False
+found_issigned_by_discord_je = False
+found_already_patched = False
+je_location = None
+
+# We are looking for a call to IsSignedByDiscord, followed by a test, followed by a je.
+# Then we patch the je into a two byte nop.
+
+md = Cs(CS_ARCH_X86, CS_MODE_64)
+md.detail = True
+for i in md.disasm(krisp_initialize, krisp_initialize_address):
+    if i.id == X86_INS_CALL:
+        if i.operands[0].type == X86_OP_IMM:
+            if i.operands[0].imm == isSignedByDiscord_address:
+                found_issigned_by_discord_call = True
+
+    if i.id == X86_INS_TEST:
+        if found_issigned_by_discord_call:
+            found_issigned_by_discord_test = True
+
+    if i.id == X86_INS_JE:
+        if found_issigned_by_discord_test:
+            found_issigned_by_discord_je = True
+            je_location = i.address
+            break
+
+    if i.id == X86_INS_NOP:
+        if found_issigned_by_discord_test:
+            found_already_patched = True
+            break
+
+if je_location:
+    print(f"Found patch location: 0x{je_location:x}")
+
+    shutil.copyfile(executable, executable + ".orig")
+    f = open(executable, 'rb+')
+    f.seek(je_location - address_to_file)
+    f.write(b'\x66\x90')  # Two byte NOP
+    f.close()
+else:
+    if found_already_patched:
+        print("Couldn't find patch location - already patched.")
+    else:
+        print("Couldn't find patch location - review manually. Sorry.")
diff --git a/discord-electron/update-package.sh b/discord-electron/update-package.sh
new file mode 100755
index 0000000..90cdc1e
--- /dev/null
+++ b/discord-electron/update-package.sh
@@ -0,0 +1,57 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+readonly all_off="$(tput sgr0)"
+readonly bold="${all_off}$(tput bold)"
+readonly white="${bold}$(tput setaf 7)"
+readonly blue="${bold}$(tput setaf 4)"
+readonly red="${bold}$(tput setaf 1)"
+
+msg() {
+	printf "${blue}::${white} $1${all_off}\n"
+}
+
+error() {
+	printf "${red}::${white} $1${all_off}\n"
+}
+
+msgbegin() {
+	printf "${blue}::${white} $1"
+}
+
+msgend() {
+	printf "$1${all_off}\n"
+}
+
+
+readonly krisp_zip='discord_krisp-1.zip'
+readonly krisp_bin='discord_krisp.node'
+
+# head to directory of this script
+cd $(dirname "$0")
+
+# update package to version used in PKGBUILD
+source PKGBUILD
+
+msg "Running updpkgsums (Updating checksums)"
+updpkgsums
+
+msg "Running mksrcinfo (Updating SRCINFO file)"
+makepkg --printsrcinfo > .SRCINFO
+
+msg "Getting Krisp module"
+curl -O "https://dl.discordapp.net/apps/linux/${_pkgver:-${pkgver}}/modules/${krisp_zip}"
+unzip "${krisp_zip}" "${krisp_bin}"
+
+msg "Checking if Krisp module is patchable (watch output)"
+python krisp-patcher.py "${krisp_bin}"
+
+#msg "Updating Krisp module checksum"
+#readonly chcksm=$(b2sum "${krisp_bin}.orig" | head -c 128)
+#sed -i "s/^_krisp_b2sum='.*'$/_krisp_b2sum='${chcksm}'/" PKGBUILD
+
+msgbegin "Cleaning up... "
+rm -f "${krisp_zip}" "${krisp_bin}" "${krisp_bin}.orig"
+
+msgend "Done"