add a vt monitor test, move getfd to sysdeps, add a check for the root user

1 files changed, 113 insertions, 1 deletions

diff --git a/src/ck-sysdeps-unix.c b/src/ck-sysdeps-unix.c
index aadca48..4bad4b6 100644
--- a/src/ck-sysdeps-unix.c
+++ b/src/ck-sysdeps-unix.c
@@ -25,10 +25,15 @@
 #include <fcntl.h>
 #include <unistd.h>
 #include <string.h>
+#include <errno.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/socket.h>
-#include <errno.h>
+#include <sys/ioctl.h>
+
+#ifdef __linux__
+#include <linux/kd.h>
+#endif
 
 #ifdef HAVE_GETPEERUCRED
 #include <ucred.h>
@@ -96,3 +101,110 @@ ck_get_socket_peer_credentials   (int      socket_fd,
 
         return ret;
 }
+
+
+/*
+ * getfd.c
+ *
+ * Get an fd for use with kbd/console ioctls.
+ * We try several things because opening /dev/console will fail
+ * if someone else used X (which does a chown on /dev/console).
+ */
+
+gboolean
+ck_fd_is_a_console (int fd)
+{
+        char arg;
+        int  kb_ok;
+
+        arg = 0;
+
+#ifdef __linux__
+        kb_ok = (ioctl (fd, KDGKBTYPE, &arg) == 0
+                 && ((arg == KB_101) || (arg == KB_84)));
+#else
+        kb_ok = 1;
+#endif
+
+        return (isatty (fd) && kb_ok);
+}
+
+static int
+open_a_console (char *fnam)
+{
+        int fd;
+
+        fd = open (fnam, O_RDONLY | O_NOCTTY);
+        if (fd < 0 && errno == EACCES)
+                fd = open (fnam, O_WRONLY | O_NOCTTY);
+
+        if (fd < 0)
+                return -1;
+
+        if (! ck_fd_is_a_console (fd)) {
+                close (fd);
+                fd = -1;
+        }
+
+        return fd;
+}
+
+int
+ck_get_a_console_fd (void)
+{
+        int fd;
+
+#ifdef _PATH_TTY
+        fd = open_a_console (_PATH_TTY);
+        if (fd >= 0)
+                return fd;
+#endif
+
+        fd = open_a_console ("/dev/tty");
+        if (fd >= 0)
+                return fd;
+
+#ifdef _PATH_CONSOLE
+        fd = open_a_console (_PATH_CONSOLE);
+        if (fd >= 0)
+                return fd;
+#endif
+
+        fd = open_a_console ("/dev/console");
+        if (fd >= 0)
+                return fd;
+
+        for (fd = 0; fd < 3; fd++) {
+                if (ck_fd_is_a_console (fd)) {
+                        return fd;
+                }
+        }
+
+        return -1;
+}
+
+gboolean
+ck_is_root_user (void)
+{
+#ifndef G_OS_WIN32
+        uid_t ruid, euid, suid; /* Real, effective and saved user ID's */
+        gid_t rgid, egid, sgid; /* Real, effective and saved group ID's */
+
+#ifdef HAVE_GETRESUID
+        if (getresuid (&ruid, &euid, &suid) != 0 ||
+            getresgid (&rgid, &egid, &sgid) != 0)
+#endif /* HAVE_GETRESUID */
+                {
+                        suid = ruid = getuid ();
+                        sgid = rgid = getgid ();
+                        euid = geteuid ();
+                        egid = getegid ();
+                }
+
+        if (ruid == 0) {
+                return TRUE;
+        }
+
+#endif
+        return FALSE;
+}