From 077949be20fb693f78d7c94d8d38df78262b1cdb Mon Sep 17 00:00:00 2001
From: tangowithfoxtrot <5676771+tangowithfoxtrot@users.noreply.github.com>
Date: Fri, 15 Nov 2024 14:27:19 -0800
Subject: [PATCH] fix: cross-compiled bin not working without emulation on
 host; static link libc

---
 crates/bws/Dockerfile | 35 ++++++++++++++++++++---------------
 1 file changed, 20 insertions(+), 15 deletions(-)

diff --git a/crates/bws/Dockerfile b/crates/bws/Dockerfile
index 07f9f3a79..061f7e6a3 100644
--- a/crates/bws/Dockerfile
+++ b/crates/bws/Dockerfile
@@ -1,7 +1,7 @@
 ###############################################
 #                 Build stage                 #
 ###############################################
-FROM --platform=$BUILDPLATFORM rust:1.81 AS build
+FROM rust:1.81 AS build
 
 # Docker buildx supplies the value for this arg
 ARG TARGETPLATFORM
@@ -13,16 +13,26 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
 # Copy required project files
 COPY . /app
 
+# Set required args for build
+ENV CARGO_TARGET_DIR='./target'
+ENV RUSTFLAGS='-C target-feature=+crt-static'
+
 # Build project
 WORKDIR /app/crates/bws
-RUN cargo build --release --bin bws
-
-# Bundle bws dependencies
-RUN mkdir /lib-bws
-RUN mkdir /lib64-bws
-
-RUN ldd /app/target/release/bws | tr -s '[:blank:]' '\n' | grep '^/lib' | xargs -I % cp % /lib-bws
-RUN ldd /app/target/release/bws | tr -s '[:blank:]' '\n' | grep '^/lib64' | xargs -I % cp % /lib64-bws
+RUN <<EOF
+  # Explicit target args are required: https://github.com/rust-lang/rust/issues/78210#issuecomment-714776007
+  case "$TARGETPLATFORM" in
+    *"linux/amd64"*)
+      cargo build --release --bin bws --target x86_64-unknown-linux-gnu
+      mv ./target/x86_64-unknown-linux-gnu/release/bws ./target/release/bws;;
+    *"linux/arm64"*)
+      cargo build --release --bin bws --target aarch64-unknown-linux-gnu
+      mv ./target/aarch64-unknown-linux-gnu/release/bws ./target/release/bws;;
+    *)
+      echo "Unsupported target platform: $TARGETPLATFORM";
+      exit 1;;
+  esac
+EOF
 
 # Make a user and HOME directory for the app stage
 RUN useradd -m app
@@ -32,7 +42,6 @@ RUN useradd -m app
 ###############################################
 FROM scratch
 
-ARG TARGETPLATFORM
 LABEL com.bitwarden.product="bitwarden"
 
 # Set a HOME directory and copy the user file
@@ -45,13 +54,9 @@ WORKDIR /home/app
 USER app
 
 # Copy built project from the build stage
-COPY --from=build /app/target/release/bws /bin/bws
+COPY --from=build /app/crates/bws/target/release/bws /bin/bws
 
 # Copy certs
 COPY --from=build /etc/ssl/certs /etc/ssl/certs
 
-# Copy bws dependencies
-COPY --from=build /lib-bws /lib
-COPY --from=build /lib64-bws /lib64
-
 ENTRYPOINT ["bws"]