login: cleanup work by Walter Harms. No logic changes.

1 files changed, 56 insertions, 46 deletions

diff --git a/loginutils/login.c b/loginutils/login.c
index af871436a..d9e9b532b 100644
--- a/loginutils/login.c
+++ b/loginutils/login.c
@@ -165,6 +165,56 @@ static int check_securetty(void)
 static ALWAYS_INLINE int check_securetty(void) { return 1; }
 #endif
 
+#if ENABLE_SELINUX
+static void initselinux(char *username, char *full_tty,
+                                                security_context_t *user_sid)
+{
+        security_context_t old_tty_sid, new_tty_sid;
+
+        if (!is_selinux_enabled())
+                return;
+
+        if (get_default_context(username, NULL, user_sid)) {
+                bb_error_msg_and_die("cannot get SID for %s", username);
+        }
+        if (getfilecon(full_tty, &old_tty_sid) < 0) {
+                bb_perror_msg_and_die("getfilecon(%s) failed", full_tty);
+        }
+        if (security_compute_relabel(user_sid, old_tty_sid,
+                                SECCLASS_CHR_FILE, &new_tty_sid) != 0) {
+                bb_perror_msg_and_die("security_change_sid(%s) failed", full_tty);
+        }
+        if (setfilecon(full_tty, new_tty_sid) != 0) {
+                bb_perror_msg_and_die("chsid(%s, %s) failed", full_tty, new_tty_sid);
+        }
+}
+#endif
+
+#if ENABLE_LOGIN_SCRIPTS
+static void run_login_script(struct passwd *pw, char *full_tty)
+{
+        char *t_argv[2];
+
+        t_argv[0] = getenv("LOGIN_PRE_SUID_SCRIPT");
+        if (t_argv[0]) {
+                t_argv[1] = NULL;
+                xsetenv("LOGIN_TTY", full_tty);
+                xsetenv("LOGIN_USER", pw->pw_name);
+                xsetenv("LOGIN_UID", utoa(pw->pw_uid));
+                xsetenv("LOGIN_GID", utoa(pw->pw_gid));
+                xsetenv("LOGIN_SHELL", pw->pw_shell);
+                spawn_and_wait(t_argv); /* NOMMU-friendly */
+                unsetenv("LOGIN_TTY");
+                unsetenv("LOGIN_USER");
+                unsetenv("LOGIN_UID");
+                unsetenv("LOGIN_GID");
+                unsetenv("LOGIN_SHELL");
+        }
+}
+#else
+void run_login_script(struct passwd *pw, char *full_tty);
+#endif
+
 static void get_username_or_die(char *buf, int size_buf)
 {
         int c, cntdown;
@@ -285,8 +335,7 @@ int login_main(int argc UNUSED_PARAM, char **argv)
         read_or_build_utent(&utent, run_by_root);
 
         if (opt & LOGIN_OPT_h) {
-                if (ENABLE_FEATURE_UTMP)
-                        safe_strncpy(utent.ut_host, opt_host, sizeof(utent.ut_host));
+                USE_FEATURE_UTMP(safe_strncpy(utent.ut_host, opt_host, sizeof(utent.ut_host));)
                 fromhost = xasprintf(" on '%s' from '%s'", short_tty, opt_host);
         } else {
                 fromhost = xasprintf(" on '%s'", short_tty);
@@ -410,54 +459,16 @@ int login_main(int argc UNUSED_PARAM, char **argv)
 
         write_utent(&utent, username);
 
-#if ENABLE_SELINUX
-        if (is_selinux_enabled()) {
-                security_context_t old_tty_sid, new_tty_sid;
+        USE_SELINUX(initselinux(username, full_tty, &user_sid));
 
-                if (get_default_context(username, NULL, &user_sid)) {
-                        bb_error_msg_and_die("cannot get SID for %s",
-                                        username);
-                }
-                if (getfilecon(full_tty, &old_tty_sid) < 0) {
-                        bb_perror_msg_and_die("getfilecon(%s) failed",
-                                        full_tty);
-                }
-                if (security_compute_relabel(user_sid, old_tty_sid,
-                                        SECCLASS_CHR_FILE, &new_tty_sid) != 0) {
-                        bb_perror_msg_and_die("security_change_sid(%s) failed",
-                                        full_tty);
-                }
-                if (setfilecon(full_tty, new_tty_sid) != 0) {
-                        bb_perror_msg_and_die("chsid(%s, %s) failed",
-                                        full_tty, new_tty_sid);
-                }
-        }
-#endif
         /* Try these, but don't complain if they fail.
          * _f_chown is safe wrt race t=ttyname(0);...;chown(t); */
         fchown(0, pw->pw_uid, pw->pw_gid);
         fchmod(0, 0600);
 
         /* We trust environment only if we run by root */
-        if (ENABLE_LOGIN_SCRIPTS && run_by_root) {
-                char *t_argv[2];
-
-                t_argv[0] = getenv("LOGIN_PRE_SUID_SCRIPT");
-                if (t_argv[0]) {
-                        t_argv[1] = NULL;
-                        xsetenv("LOGIN_TTY", full_tty);
-                        xsetenv("LOGIN_USER", pw->pw_name);
-                        xsetenv("LOGIN_UID", utoa(pw->pw_uid));
-                        xsetenv("LOGIN_GID", utoa(pw->pw_gid));
-                        xsetenv("LOGIN_SHELL", pw->pw_shell);
-                        spawn_and_wait(t_argv); /* NOMMU-friendly */
-                        unsetenv("LOGIN_TTY"  );
-                        unsetenv("LOGIN_USER" );
-                        unsetenv("LOGIN_UID"  );
-                        unsetenv("LOGIN_GID"  );
-                        unsetenv("LOGIN_SHELL");
-                }
-        }
+        if (ENABLE_LOGIN_SCRIPTS && run_by_root) 
+                run_login_script(pw, full_tty);
 
         change_identity(pw);
         tmp = pw->pw_shell;
@@ -470,11 +481,10 @@ int login_main(int argc UNUSED_PARAM, char **argv)
 
         if (pw->pw_uid == 0)
                 syslog(LOG_INFO, "root login%s", fromhost);
-#if ENABLE_SELINUX
+
         /* well, a simple setexeccon() here would do the job as well,
          * but let's play the game for now */
-        set_current_security_context(user_sid);
-#endif
+        USE_SELINUX(set_current_security_context(user_sid);)
 
         // util-linux login also does:
         // /* start new session */