1 files changed, 116 insertions, 0 deletions
diff --git a/sys/contrib/lomac/syscall_gate.c b/sys/contrib/lomac/syscall_gate.c
new file mode 100644
index 0000000..d979263
--- /dev/null
+++ b/sys/contrib/lomac/syscall_gate.c
@@ -0,0 +1,116 @@
+/*-
+ * Copyright (c) 2001 Networks Associates Technology, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $Id: syscall_gate.c,v 1.4 2001/11/05 21:23:12 bfeldman Exp $
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/conf.h>
+#include <sys/kernel.h>
+#include <sys/module.h>
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#include <sys/proc.h>
+#include <sys/syscall.h>
+#include <sys/sysent.h>
+
+#include <machine/frame.h>
+
+#include "syscall_gate.h"
+void syscall_gate_init(void);
+int syscall_gate(struct thread *td, caddr_t params);
+
+static struct syscall_gate sg;
+
+void
+syscall_gate_init(void) {
+
+	sg.sg_table = curthread->td_proc->p_sysent->sv_table;
+	bzero(sg.sg_oldsyscalls, sizeof(sg.sg_oldsyscalls));
+}
+
+int
+syscall_gate_register(int offset, sy_call_t *call, int narg, int mpsafe) {
+	struct sysent *se;
+	int error = 0;
+
+	if (offset <= 0 || offset >= SYS_MAXSYSCALL) {
+		error = EINVAL;
+		goto out;
+	}
+	if (sg.sg_oldsyscalls[offset].sy_call != NULL) {
+		error = EEXIST;
+		goto out;
+	}
+	se = &sg.sg_table[offset];
+	sg.sg_oldsyscalls[offset] = *se;
+	se->sy_call = (sy_call_t *)call;
+	se->sy_narg = narg | (mpsafe ? SYF_MPSAFE : 0);
+out:
+	return (error);
+}
+
+void
+syscall_gate_deregister(int offset) {
+	KASSERT(offset > 0 && offset < SYS_MAXSYSCALL, ("syscall offset %d out of range",
+	    offset));
+	KASSERT(sg.sg_oldsyscalls[offset].sy_call != NULL, ("deregistering nonexistant syscall %d",
+	    offset));
+	sg.sg_table[offset] = sg.sg_oldsyscalls[offset];
+	sg.sg_oldsyscalls[offset].sy_call = NULL;
+	sg.sg_oldsyscalls[offset].sy_narg = 0;
+}
+
+static int
+syscall_gate_modevent(module_t module, int event, void *unused) {
+	int i;
+
+	switch ((enum modeventtype)event) {
+	case MOD_LOAD:
+		syscall_gate_init();
+		break;
+	case MOD_UNLOAD:
+		for (i = 1; i < SYS_MAXSYSCALL; i++) {
+			struct sysent *se;
+
+			se = &sg.sg_oldsyscalls[i];
+			if (se->sy_call != NULL)
+				sg.sg_table[i] = *se;
+		}
+		break;
+	case MOD_SHUTDOWN:
+		break;
+	}
+	return (0);
+}
+
+static moduledata_t syscall_gate_moduledata = {
+	"syscall_gate",
+	&syscall_gate_modevent,
+	NULL
+};
+DECLARE_MODULE(syscall_gate, syscall_gate_moduledata, SI_SUB_DRIVERS, SI_ORDER_ANY);
+MODULE_VERSION(syscall_gate, 1);