diff -up Linux-PAM-0.99.8.1/modules/pam_unix/unix_chkpwd.c.blankpass Linux-PAM-0.99.8.1/modules/pam_unix/unix_chkpwd.c --- Linux-PAM-0.99.8.1/modules/pam_unix/unix_chkpwd.c.blankpass 2007-09-18 13:50:40.000000000 +0200 +++ Linux-PAM-0.99.8.1/modules/pam_unix/unix_chkpwd.c 2007-09-18 13:50:40.000000000 +0200 @@ -50,7 +50,7 @@ int main(int argc, char *argv[]) char pass[MAXPASS + 1]; char *option; int npass, nullok; - int force_failure = 0; + int blankpass = 0; int retval = PAM_AUTH_ERR; char *user; char *passwords[] = { pass }; @@ -115,6 +115,10 @@ int main(int argc, char *argv[]) if (npass != 1) { /* is it a valid password? */ _log_err(LOG_DEBUG, "no valid password supplied"); } + + if (*pass == '\0') { + blankpass = 1; + } retval = _unix_verify_password(user, pass, nullok); @@ -122,8 +126,11 @@ int main(int argc, char *argv[]) /* return pass or fail */ - if ((retval != PAM_SUCCESS) || force_failure) { - _log_err(LOG_NOTICE, "password check failed for user (%s)", user); + if (retval != PAM_SUCCESS) { + /* don't log if it is a test for blank password */ + if (!blankpass) { + _log_err(LOG_NOTICE, "password check failed for user (%s)", user); + } return PAM_AUTH_ERR; } else { return PAM_SUCCESS; diff -up Linux-PAM-0.99.8.1/modules/pam_unix/support.c.blankpass Linux-PAM-0.99.8.1/modules/pam_unix/support.c --- Linux-PAM-0.99.8.1/modules/pam_unix/support.c.blankpass 2007-09-18 13:50:40.000000000 +0200 +++ Linux-PAM-0.99.8.1/modules/pam_unix/support.c 2007-09-18 17:56:57.000000000 +0200 @@ -38,6 +38,9 @@ const char app_name[]="pam_unix"; +static int _unix_run_helper_binary(pam_handle_t *pamh, const char *passwd, + unsigned int ctrl, const char *user); + /* this is a front-end for module-application conversations */ int _make_remark(pam_handle_t * pamh, unsigned int ctrl, @@ -442,6 +445,13 @@ _unix_blankpasswd (pam_handle_t *pamh, u * ...and shadow password file entry for this user, * if shadowing is enabled */ + if (geteuid() || SELINUX_ENABLED) { + /* We do not have direct access to shadow. Run helper. */ + D(("running helper binary")); + if (_unix_run_helper_binary(pamh, "", ctrl, name) == PAM_SUCCESS) + return 1; + return 0; + } spwdent = pam_modutil_getspnam(pamh, name); } if (spwdent)