From 4bd08afc915945d6662cbabd19bc98b1af1c1abc Mon Sep 17 00:00:00 2001
From: Anthony Rodriguez <anthony@nezia.dev>
Date: Thu, 6 Feb 2025 14:57:06 +0100
Subject: [PATCH] programs/discord: move to directory to use canary and apply
 krisp-patcher

---
 modules/programs/default.nix                  |  2 +-
 .../{discord.nix => discord/default.nix}      | 18 +++-
 modules/programs/discord/krisp-patcher.py     | 91 +++++++++++++++++++
 3 files changed, 108 insertions(+), 3 deletions(-)
 rename modules/programs/{discord.nix => discord/default.nix} (88%)
 create mode 100644 modules/programs/discord/krisp-patcher.py

diff --git a/modules/programs/default.nix b/modules/programs/default.nix
index 18f7bfe..c063199 100644
--- a/modules/programs/default.nix
+++ b/modules/programs/default.nix
@@ -1,12 +1,12 @@
 {
   imports = [
     ./anyrun
+    ./discord
     ./editors
     ./hypr
     ./media
     ./terminal
 
-    ./discord.nix
     ./fastfetch.nix
     ./firefox.nix
     ./games.nix
diff --git a/modules/programs/discord.nix b/modules/programs/discord/default.nix
similarity index 88%
rename from modules/programs/discord.nix
rename to modules/programs/discord/default.nix
index 23dc832..b857f06 100644
--- a/modules/programs/discord.nix
+++ b/modules/programs/discord/default.nix
@@ -7,11 +7,25 @@
   inherit (lib) mkIf;
   inherit (config.local.systemVars) username;
   styleCfg = config.local.style;
+  discord = pkgs.discord-canary.override {
+    withOpenASAR = true;
+    withVencord = true;
+  };
+
+  # run once with krisp-patcher ~/.config/discordcanary/*/modules/discord_krisp/discord_krisp.node
+  krisp-patcher = pkgs.writers.writePython3Bin "krisp-patcher" {
+    libraries = with pkgs.python3Packages; [capstone pyelftools];
+    flakeIgnore = [
+      "E501" # line too long (82 > 79 characters)
+      "F403" # ‘from module import *’ used; unable to detect undefined names
+      "F405" # name may be undefined, or defined from star imports: module
+    ];
+  } (builtins.readFile ./krisp-patcher.py);
 in {
   config = mkIf config.local.profiles.desktop.enable {
     hjem.users.${username} = {
-      packages = [pkgs.vesktop];
-      files.".config/vesktop/themes/midnight-base16.css".text = with styleCfg.scheme.palette;
+      packages = [discord krisp-patcher];
+      files.".config/Vencord/themes/midnight-base16.css".text = with styleCfg.scheme.palette;
         mkIf styleCfg.enable ''
           /**
            * @name Midnight-base16
diff --git a/modules/programs/discord/krisp-patcher.py b/modules/programs/discord/krisp-patcher.py
new file mode 100644
index 0000000..2f33be5
--- /dev/null
+++ b/modules/programs/discord/krisp-patcher.py
@@ -0,0 +1,91 @@
+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(
+    "_ZN7discordL17DoKrispInitializeEv"
+)[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(256)
+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
+je_size = 0
+
+# We are looking for a call to IsSignedByDiscord, followed by a test, followed by a je.
+# Then we replace the je with nops.
+
+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
+            je_size = len(i.bytes)
+            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"\x90" * je_size
+    )  # je can be larger than 2 bytes given a large enough displacement :(
+    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.")