utmp: update update_utmp()

Remove `utmp` structure as an argument and include its logic inside the
function. This will help remove any reference to utmp from login.

Signed-off-by: Iker Pedrosa <ipedrosa@redhat.com>

lib/prototypes.h

@@ -23,7 +23,6 @@
 
 #include <sys/socket.h>
 #include <sys/stat.h>
-#include <utmp.h>
 #include <sys/types.h>
 #include <pwd.h>
 #include <grp.h>
@@ -485,30 +484,32 @@ extern int user_busy (const char *name, uid_t uid);
  *         another value on error.
  */
 extern int get_session_host (char **out);
-extern /*@null@*/struct utmp *get_current_utmp (void);
-extern struct utmp *prepare_utmp (const char *name,
-                                  const char *line,
-                                  const char *host,
-                                  /*@null@*/const struct utmp *ut);
-/*
- * failtmp - update the cumulative failure log
- *
- *	failtmp updates the (struct utmp) formatted failure log which
- *	maintains a record of all login failures.
- */
-extern void failtmp (const char *username, const struct utmp *);
+#ifndef ENABLE_LOGIND
 /**
  * @brief Update or create an utmp entry in utmp, wtmp, utmpw, or wtmpx
  *
  * @param[in] user username
  * @param[in] tty tty
  * @param[in] host hostname
- * @param[in] utent utmp entry
+ *
+ * @return 0 if utmp was updated properly,
+ *         1 on error.
  */
-extern void update_utmp (const char *user,
-                         const char *tty,
-                         const char *host,
-                         /*@null@*/const struct utmp *utent);
+extern int update_utmp (const char *user,
+                        const char *tty,
+                        const char *host);
+/**
+ * @brief Update the cumulative failure log
+ *
+ * @param[in] failent_user username
+ * @param[in] tty tty
+ * @param[in] host hostname
+ *
+ */
+extern void record_failure(const char *failent_user,
+                           const char *tty,
+                           const char *hostname);
+#endif /* ENABLE_LOGIND */
 
 /* valid.c */
 extern bool valid (const char *, const struct passwd *);

libmisc/utmp.c

@@ -61,7 +61,7 @@ static bool is_my_tty (const char tty[UT_LINESIZE])
  *	failtmp updates the (struct utmp) formatted failure log which
  *	maintains a record of all login failures.
  */
-void failtmp (const char *username, const struct utmp *failent)
+static void failtmp (const char *username, const struct utmp *failent)
 {
 	const char *ftmp;
 	int fd;
@@ -120,6 +120,7 @@ void failtmp (const char *username, const struct utmp *failent)
  *
  *	Return NULL if no entries exist in utmp for the current process.
  */
+static
 /*@null@*/ /*@only@*/struct utmp *get_current_utmp (void)
 {
 	struct utmp *ut;
@@ -220,6 +221,7 @@ static void updwtmp (const char *filename, const struct utmp *ut)
  *
  *	The returned structure shall be freed by the caller.
  */
+static
 /*@only@*/struct utmp *prepare_utmp (const char *name,
                                      const char *line,
                                      const char *host,
@@ -359,13 +361,37 @@ static int setutmp (struct utmp *ut)
 	return err;
 }
 
-void update_utmp (const char *user,
-                  const char *tty,
-                  const char *host,
-                  /*@null@*/const struct utmp *utent)
+int update_utmp (const char *user,
+                 const char *tty,
+                 const char *host)
 {
-	struct utmp  *ut  = prepare_utmp  (user, tty, host, utent);
+	struct utmp *utent, *ut;
+
+	utent = get_current_utmp ();
+	if (utent == NULL) {
+		return -1;
+	}
+
+	ut = prepare_utmp  (user, tty, host, utent);
 
 	(void) setutmp  (ut);	/* make entry in the utmp & wtmp files */
+	free (utent);
 	free (ut);
+
+	return 1;
+}
+
+void record_failure(const char *failent_user,
+                    const char *tty,
+                    const char *hostname)
+{
+	struct utmp *utent, *failent;
+
+	if (getdef_str ("FTMP_FILE") != NULL) {
+		utent = get_current_utmp ();
+		failent = prepare_utmp (failent_user, tty, hostname, utent);
+		failtmp (failent_user, failent);
+		free (utent);
+		free (failent);
+	}
 }

src/login.c

@@ -498,7 +498,7 @@ int main (int argc, char **argv)
 	struct passwd *pwd = NULL;
 	char **envp = environ;
 	const char *failent_user;
-	/*@null@*/struct utmp *utent;
+	char *host = NULL;
 
 #ifdef USE_PAM
 	int retcode;
@@ -535,19 +535,17 @@ int main (int argc, char **argv)
 		exit (1);	/* must be a terminal */
 	}
 
-	utent = get_current_utmp ();
+	err = get_session_host(&host);
 	/*
 	 * Be picky if run by normal users (possible if installed setuid
-	 * root), but not if run by root. This way it still allows logins
-	 * even if your getty is broken, or if something corrupts utmp,
-	 * but users must "exec login" which will use the existing utmp
-	 * entry (will not overwrite remote hostname).  --marekm
+	 * root), but not if run by root.
 	 */
-	if (!amroot && (NULL == utent)) {
-		(void) puts (_("No utmp entry.  You must exec \"login\" from the lowest level \"sh\""));
+	if (!amroot && (err != 0)) {
+		SYSLOG ((LOG_ERR,
+				 "No session entry, error %d.  You must exec \"login\" from the lowest level \"sh\"",
+				 err));
 		exit (1);
 	}
-	/* NOTE: utent might be NULL afterwards */
 
 	tmptty = ttyname (0);
 	if (NULL == tmptty) {
@@ -642,10 +640,8 @@ int main (int argc, char **argv)
 
 	if (rflg || hflg) {
 		cp = hostname;
-#if defined(HAVE_STRUCT_UTMP_UT_HOST)
-	} else if ((NULL != utent) && ('\0' != utent->ut_host[0])) {
-		cp = utent->ut_host;
-#endif				/* HAVE_STRUCT_UTMP_UT_HOST */
+	} else if ((host != NULL) && (host[0] != '\0')) {
+		cp = host;
 	} else {
 		cp = "";
 	}
@@ -657,6 +653,7 @@ int main (int argc, char **argv)
 		snprintf (fromhost, sizeof fromhost,
 		          " on '%.100s'", tty);
 	}
+	free(host);
 
       top:
 	/* only allow ALARM sec. for login */
@@ -1004,15 +1001,9 @@ int main (int argc, char **argv)
 		if ((NULL != pwd) && getdef_bool ("FAILLOG_ENAB")) {
 			failure (pwd->pw_uid, tty, &faillog);
 		}
-		if (getdef_str ("FTMP_FILE") != NULL) {
-			struct utmp *failent =
-				prepare_utmp (failent_user,
-				              tty,
-				              hostname,
-				              utent);
-			failtmp (failent_user, failent);
-			free (failent);
-		}
+#ifndef ENABLE_LOGIND
+		record_failure(failent_user, tty, hostname);
+#endif /* ENABLE_LOGIND */
 
 		retries--;
 		if (retries <= 0) {
@@ -1183,11 +1174,16 @@ int main (int argc, char **argv)
 		}
 	}
 
+#ifndef ENABLE_LOGIND
 	/*
 	 * The utmp entry needs to be updated to indicate the new status
 	 * of the session, the new PID and SID.
 	 */
-	update_utmp (username, tty, hostname, utent);
+	err = update_utmp (username, tty, hostname);
+	if (err != 0) {
+		SYSLOG ((LOG_WARN, "Unable to update utmp entry for %s", username));
+	}
+#endif /* ENABLE_LOGIND */
 
 	/* The pwd and spwd entries for the user have been copied.
 	 *