main: simplify warnings

Makefile

@@ -1,24 +1,10 @@
 PREFIX ?= /usr
 DESTDIR ?=
 BINDIR ?= $(PREFIX)/bin
-export GOPATH ?= $(CURDIR)/.gopath
 export GO111MODULE := on
 
 all: generate-version-and-build
 
-ifeq ($(shell go env GOOS)|$(wildcard .git),linux|)
-$(error Do not build this for Linux. Instead use the Linux kernel module. See wireguard.com/install/ for more info.)
-else ifeq ($(shell go env GOOS),linux)
-ireallywantobuildon_linux.go:
-	@printf "WARNING: This software is meant for use on non-Linux\nsystems. For Linux, please use the kernel module\ninstead. See wireguard.com/install/ for more info.\n\n" >&2
-	@printf 'package main\nconst UseTheKernelModuleInstead = 0xdeadbabe\n' > "$@"
-clean-ireallywantobuildon_linux.go:
-	@rm -f ireallywantobuildon_linux.go
-.PHONY: clean-ireallywantobuildon_linux.go
-clean: clean-ireallywantobuildon_linux.go
-wireguard-go: ireallywantobuildon_linux.go
-endif
-
 MAKEFLAGS += --no-print-directory
 
 generate-version-and-build:

main.go

@@ -40,31 +40,19 @@ func warning() {
 	if runtime.GOOS != "linux" || os.Getenv(ENV_WG_PROCESS_FOREGROUND) == "1" {
 		return
 	}
-	shouldQuit := os.Getenv("WG_I_PREFER_BUGGY_USERSPACE_TO_POLISHED_KMOD") != "1"
 
 	fmt.Fprintln(os.Stderr, "WARNING WARNING WARNING WARNING WARNING WARNING WARNING")
 	fmt.Fprintln(os.Stderr, "W                                                     G")
 	fmt.Fprintln(os.Stderr, "W   You are running this software on a Linux kernel,  G")
-	fmt.Fprintln(os.Stderr, "W   which is probably unnecessary and foolish. This   G")
+	fmt.Fprintln(os.Stderr, "W   which is probably unnecessary and misguided. This G")
 	fmt.Fprintln(os.Stderr, "W   is because the Linux kernel has built-in first    G")
 	fmt.Fprintln(os.Stderr, "W   class support for WireGuard, and this support is  G")
 	fmt.Fprintln(os.Stderr, "W   much more refined than this slower userspace      G")
 	fmt.Fprintln(os.Stderr, "W   implementation. For more information on           G")
 	fmt.Fprintln(os.Stderr, "W   installing the kernel module, please visit:       G")
 	fmt.Fprintln(os.Stderr, "W           https://www.wireguard.com/install         G")
-	if shouldQuit {
-		fmt.Fprintln(os.Stderr, "W                                                     G")
-		fmt.Fprintln(os.Stderr, "W   If you still want to use this program, against    G")
-		fmt.Fprintln(os.Stderr, "W   the advice here, please first export this         G")
-		fmt.Fprintln(os.Stderr, "W   environment variable:                             G")
-		fmt.Fprintln(os.Stderr, "W   WG_I_PREFER_BUGGY_USERSPACE_TO_POLISHED_KMOD=1    G")
-	}
 	fmt.Fprintln(os.Stderr, "W                                                     G")
 	fmt.Fprintln(os.Stderr, "WARNING WARNING WARNING WARNING WARNING WARNING WARNING")
-
-	if shouldQuit {
-		os.Exit(1)
-	}
 }
 
 func main() {
@@ -75,8 +63,6 @@ func main() {
 
 	warning()
 
-	// parse arguments
-
 	var foreground bool
 	var interfaceName string
 	if len(os.Args) < 2 || len(os.Args) > 3 {