login: fix warning "dereferencing type-punned pointer will break strict-aliasing...

This patch fix problems with odd pam_get_iten( ..., void **) API.
(tested by gcc-4.1.2-42.el5.i386)

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/login-utils/login.c b/login-utils/login.c
index 230121316d953c59e7842c1325f6e9f326a37608..16bbba8df3fd52115c59114fbe959614bb8d538f 100644 (file)
--- a/login-utils/login.c
+++ b/login-utils/login.c
@@ -342,6 +342,19 @@ logaudit(const char *tty, const char *username, const char *hostname,
 # define logaudit(tty, username, hostname, pwd, status)
 #endif /* HAVE_LIBAUDIT */
 
+#ifdef HAVE_SECURITY_PAM_MISC_H
+/* encapsulate stupid "void **" pam_get_item() API */
+int
+get_pam_username(pam_handle_t *pamh, char **name)
+{
+       const void *item = (void *) *name;
+       int rc;
+       rc = pam_get_item(pamh, PAM_USER, &item);
+       *name = (char *) item;
+       return rc;
+}
+#endif
+
 int
 main(int argc, char **argv)
 {
@@ -591,7 +604,7 @@ main(int argc, char **argv)
        int failcount=0;
 
        /* if we didn't get a user on the command line, set it to NULL */
-       pam_get_item(pamh,  PAM_USER, (const void **) &username);
+       get_pam_username(pamh, &username);
 
        /* there may be better ways to deal with some of these
           conditions, but at least this way I don't think we'll
@@ -605,7 +618,7 @@ main(int argc, char **argv)
               (retcode == PAM_USER_UNKNOWN) ||
               (retcode == PAM_CRED_INSUFFICIENT) ||
               (retcode == PAM_AUTHINFO_UNAVAIL))) {
-           pam_get_item(pamh, PAM_USER, (const void **) &username);
+           get_pam_username(pamh, &username);
 
            syslog(LOG_NOTICE,_("FAILED LOGIN %d FROM %s FOR %s, %s"),
                   failcount, hostname, username, pam_strerror(pamh, retcode));
@@ -618,7 +631,7 @@ main(int argc, char **argv)
        }
 
        if (retcode != PAM_SUCCESS) {
-           pam_get_item(pamh, PAM_USER, (const void **) &username);
+           get_pam_username(pamh, &username);
 
            if (retcode == PAM_MAXTRIES)
                syslog(LOG_NOTICE,_("TOO MANY LOGIN TRIES (%d) FROM %s FOR "
@@ -654,7 +667,7 @@ main(int argc, char **argv)
      * Grab the user information out of the password file for future usage
      * First get the username that we are actually using, though.
      */
-    retcode = pam_get_item(pamh, PAM_USER, (const void **) &username);
+    retcode = get_pam_username(pamh, &username);
     PAM_FAIL_CHECK;
 
     if (!username || !*username) {