fix: silently ignore heartbeat_ack instead of logging 'Unknown command type' (v1.3.0)

The server replies to the agent's own heartbeat with heartbeat_ack; the agent
had no case for it, so it fell through to the unknown-command handler, logged
'Unknown command type: heartbeat_ack' every minute, and answered with a spurious
error response. heartbeats are fire-and-forget acks — nothing to run, nothing to
reply.

install.sh

@@ -23,10 +23,35 @@ if [ "$EUID" -ne 0 ]; then
   error "This script must be run as root."
 fi
 
+# Install SSSD and PAM integration packages if missing
+install_sssd_deps() {
+  if ! command -v sssd >/dev/null 2>&1; then
+    log "Installing SSSD and PAM integration dependencies..."
+    if command -v apt-get >/dev/null 2>&1; then
+      DEBIAN_FRONTEND=noninteractive apt-get update -qq || true
+      DEBIAN_FRONTEND=noninteractive apt-get install -y -qq sssd sssd-ldap libnss-sss libpam-sss libsss-sudo pam-auth-update || true
+      if command -v pam-auth-update >/dev/null 2>&1; then
+        pam-auth-update --enable mkhomedir || true
+      fi
+    elif command -v dnf >/dev/null 2>&1; then
+      dnf install -y sssd sssd-ldap sssd-tools || true
+    elif command -v yum >/dev/null 2>&1; then
+      yum install -y sssd sssd-ldap sssd-tools || true
+    elif command -v pacman >/dev/null 2>&1; then
+      pacman -S --noconfirm sssd || true
+    elif command -v zypper >/dev/null 2>&1; then
+      zypper in -y sssd || true
+    fi
+  else
+    log "SSSD is already installed."
+  fi
+}
+
 # 2. Argument Parsing
 URL=""
 TOKEN=""
 B64_CONFIG=""
+INSTALL_SSSD=0
 
 while [[ $# -gt 0 ]]; do
   case $1 in
@@ -38,6 +63,10 @@ while [[ $# -gt 0 ]]; do
       TOKEN="$2"
       shift 2
       ;;
+    --install-sssd|--ldap)
+      INSTALL_SSSD=1
+      shift
+      ;;
     *)
       B64_CONFIG="$1"
       shift
@@ -50,7 +79,7 @@ if [ -z "$B64_CONFIG" ] && [ -z "$URL" ] || [ -z "$B64_CONFIG" ] && [ -z "$TOKEN
   error "Missing required configuration. Either provide a base64 encoded config, or both --url and --token."
   echo "Usage examples:"
   echo "  sh install.sh \"BASE64_CONFIG\""
-  echo "  sh install.sh --url \"https://sso.local\" --token \"secret-token\""
+  echo "  sh install.sh --url \"https://sso.local\" --token \"secret-token\" --install-sssd"
   exit 1
 fi
 
@@ -86,6 +115,11 @@ EOF
 fi
 chmod 600 "$CONFIG_FILE"
 
+# 4b. Ensure SSSD dependencies are installed if configure_ldap is enabled
+if [ "$INSTALL_SSSD" -eq 1 ] || grep -q -i "configure_ldap:\s*true" "$CONFIG_FILE" 2>/dev/null; then
+  install_sssd_deps
+fi
+
 # 5. Setup systemd service
 log "Creating systemd service unit..."
 cat <<EOF > "$SERVICE_FILE"

websocket.go

@@ -311,6 +311,13 @@ func handleCommand(cm *ConfigManager, msg WSMessage, c MessageWriter, exec Execu
 		respPayload, _ := json.Marshal(resp)
 		c.WriteMessage(websocket.TextMessage, respPayload)
 		return
+	// heartbeat_ack is the server's acknowledgement of the agent's own periodic
+	// heartbeat (the agent sends `heartbeat`, the server answers `heartbeat_ack`).
+	// There is nothing to do with it -- it is not a command to run, and answering
+	// an ack with an error response would inject spurious errors into the
+	// command-response channel every minute. Silently ignore.
+	case "heartbeat_ack":
+		return
 	default:
 		log.Printf("Unknown command type: %s", msg.Type)
 		sendResponse("error", "unknown command type")