Fix UID/GID mismatch and SSH key permissions in container

- Entrypoint now runs as root to remap the container's claude user
  UID/GID to match the host user, fixing bind mount permission errors
  on WSL
- SSH keys are mounted read-only to a staging path (/tmp/.host-ssh)
  and copied to ~/.ssh with correct permissions by the entrypoint
- Exec sessions explicitly run as the claude user
- Host UID/GID detected automatically and passed as env vars

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

container/Dockerfile

@@ -88,7 +88,9 @@ RUN mkdir -p /home/claude/.claude /home/claude/.ssh
 
 WORKDIR /workspace
 
-COPY --chown=claude:claude entrypoint.sh /home/claude/entrypoint.sh
-RUN chmod +x /home/claude/entrypoint.sh
+# ── Switch back to root for entrypoint (handles UID/GID remapping) ─────────
+USER root
+COPY entrypoint.sh /usr/local/bin/entrypoint.sh
+RUN chmod +x /usr/local/bin/entrypoint.sh
 
-ENTRYPOINT ["/home/claude/entrypoint.sh"]
+ENTRYPOINT ["/usr/local/bin/entrypoint.sh"]

container/entrypoint.sh

@@ -1,49 +1,75 @@
 #!/bin/bash
 set -e
 
-# ── SSH key permissions ──────────────────────────────────────────────────────
-# If SSH keys were mounted, fix permissions (bind mounts may have wrong perms)
-if [ -d /home/claude/.ssh ]; then
+# ── UID/GID remapping ──────────────────────────────────────────────────────
+# Match the container's claude user to the host user's UID/GID so that
+# bind-mounted files (project dir, docker socket) have correct ownership.
+if [ -n "$HOST_UID" ] && [ "$HOST_UID" != "$(id -u claude)" ]; then
+    usermod -u "$HOST_UID" claude
+fi
+if [ -n "$HOST_GID" ] && [ "$HOST_GID" != "$(id -g claude)" ]; then
+    groupmod -g "$HOST_GID" claude
+fi
+
+# Fix ownership of home directory after UID/GID change
+chown -R claude:claude /home/claude
+
+# ── SSH key setup ──────────────────────────────────────────────────────────
+# Host SSH dir is mounted read-only at /tmp/.host-ssh.
+# Copy to /home/claude/.ssh so we can fix permissions.
+if [ -d /tmp/.host-ssh ]; then
+    rm -rf /home/claude/.ssh
+    cp -a /tmp/.host-ssh /home/claude/.ssh
+    chown -R claude:claude /home/claude/.ssh
     chmod 700 /home/claude/.ssh
     find /home/claude/.ssh -type f -name "id_*" ! -name "*.pub" -exec chmod 600 {} \;
     find /home/claude/.ssh -type f -name "*.pub" -exec chmod 644 {} \;
-    # Write known_hosts fresh (not append) to avoid duplicates across restarts
-    ssh-keyscan -t ed25519,rsa github.com gitlab.com bitbucket.org > /home/claude/.ssh/known_hosts 2>/dev/null || true
-    chmod 644 /home/claude/.ssh/known_hosts
+    if [ -f /home/claude/.ssh/known_hosts ]; then
+        chmod 644 /home/claude/.ssh/known_hosts
+    fi
+    if [ -f /home/claude/.ssh/config ]; then
+        chmod 600 /home/claude/.ssh/config
+    fi
 fi
 
+# Append common host keys (avoid duplicates)
+su -s /bin/bash claude -c '
+    mkdir -p /home/claude/.ssh
+    ssh-keyscan -t ed25519,rsa github.com gitlab.com bitbucket.org >> /home/claude/.ssh/known_hosts 2>/dev/null || true
+    sort -u -o /home/claude/.ssh/known_hosts /home/claude/.ssh/known_hosts
+'
+
 # ── Git credential helper (for HTTPS token) ─────────────────────────────────
 if [ -n "$GIT_TOKEN" ]; then
-    # Use git credential-store with a protected file instead of embedding in config
     CRED_FILE="/home/claude/.git-credentials"
     : > "$CRED_FILE"
     chmod 600 "$CRED_FILE"
+    chown claude:claude "$CRED_FILE"
     echo "https://oauth2:${GIT_TOKEN}@github.com" >> "$CRED_FILE"
     echo "https://oauth2:${GIT_TOKEN}@gitlab.com" >> "$CRED_FILE"
     echo "https://oauth2:${GIT_TOKEN}@bitbucket.org" >> "$CRED_FILE"
-    git config --global credential.helper "store --file=$CRED_FILE"
-    # Clear the env var so it's not visible in /proc/*/environ
+    su -s /bin/bash claude -c "git config --global credential.helper 'store --file=$CRED_FILE'"
     unset GIT_TOKEN
 fi
 
 # ── Git user config ──────────────────────────────────────────────────────────
 if [ -n "$GIT_USER_NAME" ]; then
-    git config --global user.name "$GIT_USER_NAME"
+    su -s /bin/bash claude -c "git config --global user.name '$GIT_USER_NAME'"
 fi
 if [ -n "$GIT_USER_EMAIL" ]; then
-    git config --global user.email "$GIT_USER_EMAIL"
+    su -s /bin/bash claude -c "git config --global user.email '$GIT_USER_EMAIL'"
 fi
 
 # ── Docker socket permissions ────────────────────────────────────────────────
 if [ -S /var/run/docker.sock ]; then
     DOCKER_GID=$(stat -c '%g' /var/run/docker.sock)
     if ! getent group "$DOCKER_GID" > /dev/null 2>&1; then
-        sudo groupadd -g "$DOCKER_GID" docker-host
+        groupadd -g "$DOCKER_GID" docker-host
     fi
     DOCKER_GROUP=$(getent group "$DOCKER_GID" | cut -d: -f1)
-    sudo usermod -aG "$DOCKER_GROUP" claude
+    usermod -aG "$DOCKER_GROUP" claude
 fi
 
-# ── Stay alive ───────────────────────────────────────────────────────────────
+# ── Stay alive as claude ─────────────────────────────────────────────────────
 echo "Triple-C container ready."
-exec sleep infinity
+exec su -s /bin/bash claude -c "exec sleep infinity"