diff options
Diffstat (limited to 'sys/security/lomac/syscall_gate.c')
-rw-r--r-- | sys/security/lomac/syscall_gate.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/sys/security/lomac/syscall_gate.c b/sys/security/lomac/syscall_gate.c new file mode 100644 index 0000000..56817fc --- /dev/null +++ b/sys/security/lomac/syscall_gate.c @@ -0,0 +1,125 @@ +/*- + * Copyright (c) 2001 Networks Associates Technologies, Inc. + * All rights reserved. + * + * This software was developed for the FreeBSD Project by NAI Labs, the + * Security Research Division of Network Associates, Inc. under + * DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA + * CHATS research program. + * + * 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. + * 3. The name of the author may not be used to endorse or promote + * products derived from this software without specific prior written + * permission. + * + * 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. + * + * $Id$ + * $FreeBSD$ + */ + +#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); |