1 files changed, 70 insertions, 0 deletions
diff --git a/modules/pam_securetty/pam_securetty.c b/modules/pam_securetty/pam_securetty.c
index e69de29..bd81ea5 100644
--- a/modules/pam_securetty/pam_securetty.c
+++ b/modules/pam_securetty/pam_securetty.c
@@ -0,0 +1,70 @@
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <string.h>
+#include <ttyent.h>
+#include <pwd.h>
+
+
+#define PAM_SM_ACCOUNT
+
+#include <security/pam_appl.h>
+#include <security/pam_modules.h>
+#include <security/pam_mod_misc.h>
+
+#define TTY_PREFIX      "/dev/"
+
+
+PAM_EXTERN int
+pam_sm_acct_mgmt(pam_handle_t * pamh, int flags,
+		int argc, const char * argv[]) 
+{
+	struct passwd *pwd;
+	struct ttyent *ttyinfo;
+	const char *user;
+	const char *tty; 
+	int pam_err;
+
+	if ( ( (pam_err = pam_get_user(pamh, &user, NULL)) != PAM_SUCCESS ) 
+			|| ( user == NULL ) )  {
+		PAM_ERROR("Error recovering username.");
+		return (pam_err);
+	}
+
+	if ( (pwd = getpwnam(user)) == NULL ) { 
+		PAM_ERROR("Could not get passwd entry for user [%s]",user);
+		return (PAM_SERVICE_ERR);
+	}
+
+	if ( pwd->pw_uid  != 0 ) { 
+		/* secure tty applies only to root */
+		return (PAM_SUCCESS);
+	}
+
+	if ( (pam_err = pam_get_item(pamh, PAM_TTY,(void *) &tty) ) != PAM_SUCCESS ) { 
+		return (pam_err);
+	}	
+
+	if (tty != NULL && strncmp(TTY_PREFIX, tty, sizeof(TTY_PREFIX)) == 0) {
+		PAM_LOG("tty starts with " TTY_PREFIX);
+		/* skip prefix */
+		tty = (const char *)tty + sizeof(TTY_PREFIX) - 1;
+	}
+
+	/*
+	 * Linux-PAM, before checking the actual tty, 
+	 * opens /etc/securettys to check if it's world
+	 * writable or not a normal file and only continues 
+	 * if neither is correct. Sounds like a good idea - 
+	 * maybe it should be done here as well...
+	 */
+
+
+	if ( tty != NULL && (ttyinfo = getttynam(tty)) != NULL && 
+			(ttyinfo->ty_status & TTY_SECURE) != 0) 
+		return (PAM_SUCCESS);
+
+	PAM_ERROR("Access denied: tty %s is not secure", tty);
+	return (PAM_AUTH_ERR);
+}
+
+PAM_MODULE_ENTRY("pam_securetty");