1 files changed, 95 insertions, 0 deletions
diff --git a/netinstall-gui.c b/netinstall-gui.c
new file mode 100644
index 000000000000..e5d1bcc48d68
--- /dev/null
+++ b/netinstall-gui.c
@@ -0,0 +1,95 @@
+/*
+ * (C) 2020-2021 by Christian Hesse <mail@eworm.de>
+ *
+ * This software may be used and distributed according to the terms
+ * of the GNU General Public License, incorporated herein by reference.
+ *
+ * Running Mikrotik netinstall with unprivileged user requires ambient
+ * capability CAP_NET_BIND_SERVICE. This is a wrapper to run it in wine.
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/capability.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#define WINE_PATH		"/usr/bin/wine"
+#define NETINSTALL_EXE_PATH	"/usr/lib/netinstall/netinstall.exe"
+
+int main(int argc, char ** argv) {
+  cap_t caps;
+  cap_flag_value_t cap_effective = 0, cap_permitted = 0;
+  const cap_value_t cap = CAP_NET_BIND_SERVICE;
+
+  if (!CAP_IS_SUPPORTED(cap)) {
+    fprintf(stderr, "Capability CAP_NET_BIND_SERVICE is not supported.\n");
+    goto out10;
+  }
+  if ((caps = cap_get_proc()) == NULL) {
+    perror("cap_get_proc");
+    goto out10;
+  }
+  if (cap_get_flag(caps, cap, CAP_EFFECTIVE, &cap_effective) == -1 ||
+      cap_get_flag(caps, cap, CAP_PERMITTED, &cap_permitted) == -1 ||
+      cap_effective == 0 || cap_permitted == 0) {
+    fprintf(stderr, "Capability CAP_NET_BIND_SERVICE is not available. Set it with setcap(8).\n");
+    goto out20;
+  }
+  if (cap_set_flag(caps, CAP_INHERITABLE, 1, &cap, CAP_SET) == -1) {
+    perror("cap_set_flag: setting CAP_INHERITABLE for CAP_NET_BIND_SERVICE");
+    goto out20;
+  }
+  if (cap_set_proc(caps) == -1) {
+    perror("cap_set_proc");
+    goto out20;
+  }
+  if (cap_free(caps) == -1) {
+    perror("cap_free");
+    goto out10;
+  }
+  if (cap_set_ambient(cap, CAP_SET) == -1) {
+    perror("cap_set_ambient: setting CAP_NET_BIND_SERVICE");
+    goto out10;
+  }
+
+  struct stat st;
+  const char *home = getenv("HOME");
+  char wineprefix[256];
+  snprintf(wineprefix, sizeof(wineprefix), "%s/.netinstall/wine/", home);
+
+  setenv("WINEPREFIX", wineprefix, 1);
+  setenv("WINEARCH", "win64", 1);
+  setenv("WINEDLLOVERRIDES", "mscoree=", 1);
+  setenv("WINEDEBUG", "-all", 1);
+
+  if (chdir(home) == -1) {
+    perror("chdir: changing to home directory");
+    goto out10;
+  }
+
+  if (stat(".netinstall/", &st) == -1) {
+    if (mkdir(".netinstall/", 0777) == -1) {
+      perror("mkdir: creating directory '.netinstall/'");
+      goto out10;
+    }
+
+    if (system("wineboot -u") != 0) {
+      perror("system: running wineboot");
+      goto out10;
+    }
+  }
+
+  char * const newargv[] = { "wine", NETINSTALL_EXE_PATH, NULL };
+  execv(WINE_PATH, newargv);
+
+  /* execv() returns only on error */
+  perror("execv");
+
+out20:
+  cap_free(caps);
+
+out10:
+  return EXIT_FAILURE;
+}