pam_localuser: do not call pam_sm_authenticate

Calling an exported function from the module is unsafe as there is no
guarantee that the function that will be actually called is the one that
is provided by the module.

* modules/pam_localuser/pam_localuser.c (pam_sm_authenticate): Rename
to pam_localuser, add static qualifier, remove "flags" argument.
Update all callers.  Add a new pam_sm_authenticate as a thin wrapper
around pam_localuser.

1 files changed, 21 insertions, 11 deletions

diff --git a/modules/pam_localuser/pam_localuser.c b/modules/pam_localuser/pam_localuser.c
index a9f2233c..e47bb00f 100644
--- a/modules/pam_localuser/pam_localuser.c
+++ b/modules/pam_localuser/pam_localuser.c
@@ -49,9 +49,8 @@
 #include <security/pam_ext.h>
 #include "pam_inline.h"
 
-int
-pam_sm_authenticate(pam_handle_t *pamh, int flags UNUSED,
-		    int argc, const char **argv)
+static int
+pam_localuser(pam_handle_t *pamh, int argc, const char **argv)
 {
 	int i;
 	int rc;
@@ -102,25 +101,36 @@ pam_sm_setcred(pam_handle_t *pamh UNUSED, int flags UNUSED,
 }
 
 int
-pam_sm_acct_mgmt(pam_handle_t *pamh, int flags, int argc, const char **argv)
+pam_sm_authenticate(pam_handle_t *pamh, int flags UNUSED,
+		    int argc, const char **argv)
+{
+	return pam_localuser(pamh, argc, argv);
+}
+
+int
+pam_sm_acct_mgmt(pam_handle_t *pamh, int flags UNUSED,
+		 int argc, const char **argv)
 {
-	return pam_sm_authenticate(pamh, flags, argc, argv);
+	return pam_localuser(pamh, argc, argv);
 }
 
 int
-pam_sm_open_session(pam_handle_t *pamh, int flags, int argc, const char **argv)
+pam_sm_open_session(pam_handle_t *pamh, int flags UNUSED,
+		    int argc, const char **argv)
 {
-	return pam_sm_authenticate(pamh, flags, argc, argv);
+	return pam_localuser(pamh, argc, argv);
 }
 
 int
-pam_sm_close_session(pam_handle_t *pamh, int flags, int argc, const char **argv)
+pam_sm_close_session(pam_handle_t *pamh, int flags UNUSED,
+		     int argc, const char **argv)
 {
-	return pam_sm_authenticate(pamh, flags, argc, argv);
+	return pam_localuser(pamh, argc, argv);
 }
 
 int
-pam_sm_chauthtok(pam_handle_t *pamh, int flags, int argc, const char **argv)
+pam_sm_chauthtok(pam_handle_t *pamh, int flags UNUSED,
+		 int argc, const char **argv)
 {
-	return pam_sm_authenticate(pamh, flags, argc, argv);
+	return pam_localuser(pamh, argc, argv);
 }