PERFORCE change 40057 for review
Robert Watson
rwatson at FreeBSD.org
Mon Oct 20 19:05:38 PDT 2003
http://perforce.freebsd.org/chv.cgi?CH=40057
Change 40057 by rwatson at rwatson_tislabs on 2003/10/20 19:05:22
Move credential/process/vm-related MAC entry points and
infrastructure from kern_mac.c to mac_process.c. Split of
functionality also still not perfect: had to export
mac_enforce_vm since kern_mac relies on it during credential
changes due to system calls.
Affected files ...
.. //depot/projects/trustedbsd/mac/sys/conf/files#91 edit
.. //depot/projects/trustedbsd/mac/sys/kern/kern_mac.c#419 edit
.. //depot/projects/trustedbsd/mac/sys/security/mac/mac_internal.h#7 edit
.. //depot/projects/trustedbsd/mac/sys/security/mac/mac_process.c#2 edit
Differences ...
==== //depot/projects/trustedbsd/mac/sys/conf/files#91 (text+ko) ====
@@ -1592,6 +1592,7 @@
security/mac/mac_net.c optional mac
security/mac/mac_pipe.c optional mac
security/mac/mac_posix_sem.c optional mac
+security/mac/mac_process.c optional mac
security/mac/mac_system.c optional mac
security/mac/mac_sysv_msg.c optional mac
security/mac/mac_sysv_sem.c optional mac
==== //depot/projects/trustedbsd/mac/sys/kern/kern_mac.c#419 (text+ko) ====
@@ -130,46 +130,13 @@
int mac_labelmbufs = 0;
#endif
-int mac_enforce_process = 1;
-SYSCTL_INT(_security_mac, OID_AUTO, enforce_process, CTLFLAG_RW,
- &mac_enforce_process, 0, "Enforce MAC policy on inter-process operations");
-TUNABLE_INT("security.mac.enforce_process", &mac_enforce_process);
-
-static int mac_enforce_vm = 1;
-SYSCTL_INT(_security_mac, OID_AUTO, enforce_vm, CTLFLAG_RW,
- &mac_enforce_vm, 0, "Enforce MAC policy on vm operations");
-TUNABLE_INT("security.mac.enforce_vm", &mac_enforce_vm);
-
-static int mac_mmap_revocation = 0;
-SYSCTL_INT(_security_mac, OID_AUTO, mmap_revocation, CTLFLAG_RW,
- &mac_mmap_revocation, 0, "Revoke mmap access to files on subject "
- "relabel");
-
-static int mac_mmap_revocation_via_cow = 1;
-SYSCTL_INT(_security_mac, OID_AUTO, mmap_revocation_via_cow, CTLFLAG_RW,
- &mac_mmap_revocation_via_cow, 0, "Revoke mmap access to files via "
- "copy-on-write semantics, or by removing all write access");
-
#ifdef MAC_DEBUG
SYSCTL_NODE(_security_mac, OID_AUTO, debug, CTLFLAG_RW, 0,
"TrustedBSD MAC debug info");
-
-static int mac_debug_label_fallback = 0;
-SYSCTL_INT(_security_mac_debug, OID_AUTO, label_fallback, CTLFLAG_RW,
- &mac_debug_label_fallback, 0, "Filesystems should fall back to fs label"
- "when label is corrupted.");
-TUNABLE_INT("security.mac.debug_label_fallback",
- &mac_debug_label_fallback);
-
SYSCTL_NODE(_security_mac_debug, OID_AUTO, counters, CTLFLAG_RW, 0,
"TrustedBSD MAC object counters");
-static unsigned int nmaccreds, nmactemp, nmacprocs;
-
-SYSCTL_UINT(_security_mac_debug_counters, OID_AUTO, creds, CTLFLAG_RD,
- &nmaccreds, 0, "number of ucreds in use");
-SYSCTL_UINT(_security_mac_debug_counters, OID_AUTO, procs, CTLFLAG_RD,
- &nmacprocs, 0, "number of procs in use");
+static unsigned int nmactemp;
SYSCTL_UINT(_security_mac_debug_counters, OID_AUTO, temp, CTLFLAG_RD,
&nmactemp, 0, "number of temporary labels in use");
#endif
@@ -177,9 +144,6 @@
static int mac_policy_register(struct mac_policy_conf *mpc);
static int mac_policy_unregister(struct mac_policy_conf *mpc);
-static void mac_cred_mmapped_drop_perms_recurse(struct thread *td,
- struct ucred *cred, struct vm_map *map);
-
MALLOC_DEFINE(M_MACTEMP, "mactemp", "MAC temporary label storage");
/*
@@ -575,56 +539,6 @@
/* implicit: label->l_flags &= ~MAC_FLAG_INITIALIZED; */
}
-static void
-mac_init_cred_label(struct label *label)
-{
-
- mac_init_label(label);
- MAC_PERFORM(init_cred_label, label);
- MAC_DEBUG_COUNTER_INC(&nmaccreds);
-}
-
-void
-mac_init_cred(struct ucred *cred)
-{
-
- mac_init_cred_label(&cred->cr_label);
-}
-
-void
-mac_init_proc(struct proc *p)
-{
-
- mac_init_label(&p->p_label);
- MAC_PERFORM(init_proc_label, &p->p_label);
- MAC_DEBUG_COUNTER_INC(&nmacprocs);
-}
-
-static void
-mac_destroy_cred_label(struct label *label)
-{
-
- MAC_PERFORM(destroy_cred_label, label);
- mac_destroy_label(label);
- MAC_DEBUG_COUNTER_DEC(&nmaccreds);
-}
-
-void
-mac_destroy_cred(struct ucred *cred)
-{
-
- mac_destroy_cred_label(&cred->cr_label);
-}
-
-void
-mac_destroy_proc(struct proc *p)
-{
-
- MAC_PERFORM(destroy_proc_label, &p->p_label);
- mac_destroy_label(&p->p_label);
- MAC_DEBUG_COUNTER_DEC(&nmacprocs);
-}
-
int
mac_check_structmac_consistent(struct mac *mac)
{
@@ -636,367 +550,6 @@
return (0);
}
-static int
-mac_externalize_cred_label(struct label *label, char *elements,
- char *outbuf, size_t outbuflen, int flags)
-{
- int error;
-
- MAC_EXTERNALIZE(cred_label, label, elements, outbuf, outbuflen);
-
- return (error);
-}
-
-static int
-mac_internalize_cred_label(struct label *label, char *string)
-{
- int error;
-
- MAC_INTERNALIZE(cred_label, label, string);
-
- return (error);
-}
-
-/*
- * Initialize MAC label for the first kernel process, from which other
- * kernel processes and threads are spawned.
- */
-void
-mac_create_proc0(struct ucred *cred)
-{
-
- MAC_PERFORM(create_proc0, cred);
-}
-
-/*
- * Initialize MAC label for the first userland process, from which other
- * userland processes and threads are spawned.
- */
-void
-mac_create_proc1(struct ucred *cred)
-{
-
- MAC_PERFORM(create_proc1, cred);
-}
-
-void
-mac_thread_userret(struct thread *td)
-{
-
- MAC_PERFORM(thread_userret, td);
-}
-
-/*
- * When a new process is created, its label must be initialized. Generally,
- * this involves inheritence from the parent process, modulo possible
- * deltas. This function allows that processing to take place.
- */
-void
-mac_create_cred(struct ucred *parent_cred, struct ucred *child_cred)
-{
-
- MAC_PERFORM(create_cred, parent_cred, child_cred);
-}
-
-int
-mac_execve_enter(struct image_params *imgp, struct mac *mac_p,
- struct label *execlabelstorage)
-{
- struct mac mac;
- char *buffer;
- int error;
-
- if (mac_p == NULL)
- return (0);
-
- error = copyin(mac_p, &mac, sizeof(mac));
- if (error)
- return (error);
-
- error = mac_check_structmac_consistent(&mac);
- if (error)
- return (error);
-
- buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
- error = copyinstr(mac.m_string, buffer, mac.m_buflen, NULL);
- if (error) {
- free(buffer, M_MACTEMP);
- return (error);
- }
-
- mac_init_cred_label(execlabelstorage);
- error = mac_internalize_cred_label(execlabelstorage, buffer);
- free(buffer, M_MACTEMP);
- if (error) {
- mac_destroy_cred_label(execlabelstorage);
- return (error);
- }
- imgp->execlabel = execlabelstorage;
- return (0);
-}
-
-void
-mac_execve_exit(struct image_params *imgp)
-{
- if (imgp->execlabel != NULL)
- mac_destroy_cred_label(imgp->execlabel);
-}
-
-/*
- * When relabeling a process, call out to the policies for the maximum
- * permission allowed for each object type we know about in its
- * memory space, and revoke access (in the least surprising ways we
- * know) when necessary. The process lock is not held here.
- */
-void
-mac_cred_mmapped_drop_perms(struct thread *td, struct ucred *cred)
-{
-
- /* XXX freeze all other threads */
- mac_cred_mmapped_drop_perms_recurse(td, cred,
- &td->td_proc->p_vmspace->vm_map);
- /* XXX allow other threads to continue */
-}
-
-static __inline const char *
-prot2str(vm_prot_t prot)
-{
-
- switch (prot & VM_PROT_ALL) {
- case VM_PROT_READ:
- return ("r--");
- case VM_PROT_READ | VM_PROT_WRITE:
- return ("rw-");
- case VM_PROT_READ | VM_PROT_EXECUTE:
- return ("r-x");
- case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE:
- return ("rwx");
- case VM_PROT_WRITE:
- return ("-w-");
- case VM_PROT_EXECUTE:
- return ("--x");
- case VM_PROT_WRITE | VM_PROT_EXECUTE:
- return ("-wx");
- default:
- return ("---");
- }
-}
-
-static void
-mac_cred_mmapped_drop_perms_recurse(struct thread *td, struct ucred *cred,
- struct vm_map *map)
-{
- struct vm_map_entry *vme;
- int result;
- vm_prot_t revokeperms;
- vm_object_t object;
- vm_ooffset_t offset;
- struct vnode *vp;
-
- if (!mac_mmap_revocation)
- return;
-
- vm_map_lock_read(map);
- for (vme = map->header.next; vme != &map->header; vme = vme->next) {
- if (vme->eflags & MAP_ENTRY_IS_SUB_MAP) {
- mac_cred_mmapped_drop_perms_recurse(td, cred,
- vme->object.sub_map);
- continue;
- }
- /*
- * Skip over entries that obviously are not shared.
- */
- if (vme->eflags & (MAP_ENTRY_COW | MAP_ENTRY_NOSYNC) ||
- !vme->max_protection)
- continue;
- /*
- * Drill down to the deepest backing object.
- */
- offset = vme->offset;
- object = vme->object.vm_object;
- if (object == NULL)
- continue;
- while (object->backing_object != NULL) {
- object = object->backing_object;
- offset += object->backing_object_offset;
- }
- /*
- * At the moment, vm_maps and objects aren't considered
- * by the MAC system, so only things with backing by a
- * normal object (read: vnodes) are checked.
- */
- if (object->type != OBJT_VNODE)
- continue;
- vp = (struct vnode *)object->handle;
- vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
- result = vme->max_protection;
- mac_check_vnode_mmap_downgrade(cred, vp, &result);
- VOP_UNLOCK(vp, 0, td);
- /*
- * Find out what maximum protection we may be allowing
- * now but a policy needs to get removed.
- */
- revokeperms = vme->max_protection & ~result;
- if (!revokeperms)
- continue;
- printf("pid %ld: revoking %s perms from %#lx:%ld "
- "(max %s/cur %s)\n", (long)td->td_proc->p_pid,
- prot2str(revokeperms), (u_long)vme->start,
- (long)(vme->end - vme->start),
- prot2str(vme->max_protection), prot2str(vme->protection));
- vm_map_lock_upgrade(map);
- /*
- * This is the really simple case: if a map has more
- * max_protection than is allowed, but it's not being
- * actually used (that is, the current protection is
- * still allowed), we can just wipe it out and do
- * nothing more.
- */
- if ((vme->protection & revokeperms) == 0) {
- vme->max_protection -= revokeperms;
- } else {
- if (revokeperms & VM_PROT_WRITE) {
- /*
- * In the more complicated case, flush out all
- * pending changes to the object then turn it
- * copy-on-write.
- */
- vm_object_reference(object);
- vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
- VM_OBJECT_LOCK(object);
- vm_object_page_clean(object,
- OFF_TO_IDX(offset),
- OFF_TO_IDX(offset + vme->end - vme->start +
- PAGE_MASK),
- OBJPC_SYNC);
- VM_OBJECT_UNLOCK(object);
- VOP_UNLOCK(vp, 0, td);
- vm_object_deallocate(object);
- /*
- * Why bother if there's no read permissions
- * anymore? For the rest, we need to leave
- * the write permissions on for COW, or
- * remove them entirely if configured to.
- */
- if (!mac_mmap_revocation_via_cow) {
- vme->max_protection &= ~VM_PROT_WRITE;
- vme->protection &= ~VM_PROT_WRITE;
- } if ((revokeperms & VM_PROT_READ) == 0)
- vme->eflags |= MAP_ENTRY_COW |
- MAP_ENTRY_NEEDS_COPY;
- }
- if (revokeperms & VM_PROT_EXECUTE) {
- vme->max_protection &= ~VM_PROT_EXECUTE;
- vme->protection &= ~VM_PROT_EXECUTE;
- }
- if (revokeperms & VM_PROT_READ) {
- vme->max_protection = 0;
- vme->protection = 0;
- }
- pmap_protect(map->pmap, vme->start, vme->end,
- vme->protection & ~revokeperms);
- vm_map_simplify_entry(map, vme);
- }
- vm_map_lock_downgrade(map);
- }
- vm_map_unlock_read(map);
-}
-
-/*
- * When the subject's label changes, it may require revocation of privilege
- * to mapped objects. This can't be done on-the-fly later with a unified
- * buffer cache.
- */
-static void
-mac_relabel_cred(struct ucred *cred, struct label *newlabel)
-{
-
- MAC_PERFORM(relabel_cred, cred, newlabel);
-}
-
-static int
-mac_check_cred_relabel(struct ucred *cred, struct label *newlabel)
-{
- int error;
-
- MAC_CHECK(check_cred_relabel, cred, newlabel);
-
- return (error);
-}
-
-int
-mac_check_cred_visible(struct ucred *u1, struct ucred *u2)
-{
- int error;
-
- if (!mac_enforce_process)
- return (0);
-
- MAC_CHECK(check_cred_visible, u1, u2);
-
- return (error);
-}
-
-int
-mac_check_proc_debug(struct ucred *cred, struct proc *proc)
-{
- int error;
-
- PROC_LOCK_ASSERT(proc, MA_OWNED);
-
- if (!mac_enforce_process)
- return (0);
-
- MAC_CHECK(check_proc_debug, cred, proc);
-
- return (error);
-}
-
-int
-mac_check_proc_sched(struct ucred *cred, struct proc *proc)
-{
- int error;
-
- PROC_LOCK_ASSERT(proc, MA_OWNED);
-
- if (!mac_enforce_process)
- return (0);
-
- MAC_CHECK(check_proc_sched, cred, proc);
-
- return (error);
-}
-
-int
-mac_check_proc_signal(struct ucred *cred, struct proc *proc, int signum)
-{
- int error;
-
- PROC_LOCK_ASSERT(proc, MA_OWNED);
-
- if (!mac_enforce_process)
- return (0);
-
- MAC_CHECK(check_proc_signal, cred, proc, signum);
-
- return (error);
-}
-
-int
-mac_check_proc_wait(struct ucred *cred, struct proc *proc)
-{
- int error;
-
- PROC_LOCK_ASSERT(proc, MA_OWNED);
-
- if (!mac_enforce_process)
- return (0);
-
- MAC_CHECK(check_proc_wait, cred, proc);
-
- return (error);
-}
-
int
__mac_get_pid(struct thread *td, struct __mac_get_pid_args *uap)
{
==== //depot/projects/trustedbsd/mac/sys/security/mac/mac_internal.h#7 (text+ko) ====
@@ -57,6 +57,7 @@
extern int mac_late;
extern int mac_enforce_process;
extern int mac_enforce_sysv;
+extern int mac_enforce_vm;
#ifndef MAC_ALWAYS_LABEL_MBUF
extern int mac_labelmbufs;
#endif
@@ -100,6 +101,15 @@
* the namespaces, etc, should work for these, so for now, sort by
* object type.
*/
+int mac_check_cred_relabel(struct ucred *cred, struct label *newlabel);
+void mac_destroy_cred_label(struct label *label);
+int mac_externalize_cred_label(struct label *label, char *elements,
+ char *outbuf, size_t outbuflen, int flags);
+void mac_init_cred_label(struct label *label);
+int mac_internalize_cred_label(struct label *label, char *string);
+void mac_relabel_cred(struct ucred *cred, struct label *newlabel);
+
+
void mac_copy_pipe_label(struct label *src, struct label *dest);
void mac_destroy_pipe_label(struct label *label);
int mac_externalize_pipe_label(struct label *label, char *elements,
==== //depot/projects/trustedbsd/mac/sys/security/mac/mac_process.c#2 (text+ko) ====
@@ -34,39 +34,26 @@
* SUCH DAMAGE.
*/
-/*
- * Framework for extensible kernel access control. Kernel and userland
- * interface to the framework, policy registration and composition.
- */
-
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/sys/kern/kern_mac.c,v 1.99 2003/09/29 18:35:17 rwatson Exp $");
#include "opt_mac.h"
-#include "opt_devfs.h"
#include <sys/param.h>
#include <sys/condvar.h>
-#include <sys/extattr.h>
#include <sys/imgact.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/mac.h>
-#include <sys/module.h>
#include <sys/proc.h>
#include <sys/sbuf.h>
#include <sys/systm.h>
-#include <sys/sysproto.h>
-#include <sys/sysent.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/file.h>
#include <sys/namei.h>
-#include <sys/socket.h>
-#include <sys/pipe.h>
-#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <vm/vm.h>
@@ -76,66 +63,14 @@
#include <sys/mac_policy.h>
-#include <fs/devfs/devfs.h>
-
-#include <net/bpfdesc.h>
-#include <net/if.h>
-#include <net/if_var.h>
-
-#include <netinet/in.h>
-#include <netinet/ip_var.h>
-
#include <security/mac/mac_internal.h>
-#ifdef MAC
-
-/*
- * Declare that the kernel provides MAC support, version 1. This permits
- * modules to refuse to be loaded if the necessary support isn't present,
- * even if it's pre-boot.
- */
-MODULE_VERSION(kernel_mac_support, 1);
-
-SYSCTL_NODE(_security, OID_AUTO, mac, CTLFLAG_RW, 0,
- "TrustedBSD MAC policy controls");
-
-#if MAC_MAX_SLOTS > 32
-#error "MAC_MAX_SLOTS too large"
-#endif
-
-static unsigned int mac_max_slots = MAC_MAX_SLOTS;
-static unsigned int mac_slot_offsets_free = (1 << MAC_MAX_SLOTS) - 1;
-SYSCTL_UINT(_security_mac, OID_AUTO, max_slots, CTLFLAG_RD,
- &mac_max_slots, 0, "");
-
-/*
- * Has the kernel started generating labeled objects yet? All read/write
- * access to this variable is serialized during the boot process. Following
- * the end of serialization, we don't update this flag; no locking.
- */
-int mac_late = 0;
-
-/*
- * Flag to indicate whether or not we should allocate label storage for
- * new mbufs. Since most dynamic policies we currently work with don't
- * rely on mbuf labeling, try to avoid paying the cost of mtag allocation
- * unless specifically notified of interest. One result of this is
- * that if a dynamically loaded policy requests mbuf labels, it must
- * be able to deal with a NULL label being returned on any mbufs that
- * were already in flight when the policy was loaded. Since the policy
- * already has to deal with uninitialized labels, this probably won't
- * be a problem. Note: currently no locking. Will this be a problem?
- */
-#ifndef MAC_ALWAYS_LABEL_MBUF
-int mac_labelmbufs = 0;
-#endif
-
int mac_enforce_process = 1;
SYSCTL_INT(_security_mac, OID_AUTO, enforce_process, CTLFLAG_RW,
&mac_enforce_process, 0, "Enforce MAC policy on inter-process operations");
TUNABLE_INT("security.mac.enforce_process", &mac_enforce_process);
-static int mac_enforce_vm = 1;
+int mac_enforce_vm = 1;
SYSCTL_INT(_security_mac, OID_AUTO, enforce_vm, CTLFLAG_RW,
&mac_enforce_vm, 0, "Enforce MAC policy on vm operations");
TUNABLE_INT("security.mac.enforce_vm", &mac_enforce_vm);
@@ -151,431 +86,17 @@
"copy-on-write semantics, or by removing all write access");
#ifdef MAC_DEBUG
-SYSCTL_NODE(_security_mac, OID_AUTO, debug, CTLFLAG_RW, 0,
- "TrustedBSD MAC debug info");
-
-static int mac_debug_label_fallback = 0;
-SYSCTL_INT(_security_mac_debug, OID_AUTO, label_fallback, CTLFLAG_RW,
- &mac_debug_label_fallback, 0, "Filesystems should fall back to fs label"
- "when label is corrupted.");
-TUNABLE_INT("security.mac.debug_label_fallback",
- &mac_debug_label_fallback);
-
-SYSCTL_NODE(_security_mac_debug, OID_AUTO, counters, CTLFLAG_RW, 0,
- "TrustedBSD MAC object counters");
-
-static unsigned int nmaccreds, nmactemp, nmacprocs;
-
+static unsigned int nmaccreds, nmacprocs;
SYSCTL_UINT(_security_mac_debug_counters, OID_AUTO, creds, CTLFLAG_RD,
&nmaccreds, 0, "number of ucreds in use");
SYSCTL_UINT(_security_mac_debug_counters, OID_AUTO, procs, CTLFLAG_RD,
&nmacprocs, 0, "number of procs in use");
-SYSCTL_UINT(_security_mac_debug_counters, OID_AUTO, temp, CTLFLAG_RD,
- &nmactemp, 0, "number of temporary labels in use");
#endif
-static int mac_policy_register(struct mac_policy_conf *mpc);
-static int mac_policy_unregister(struct mac_policy_conf *mpc);
-
static void mac_cred_mmapped_drop_perms_recurse(struct thread *td,
struct ucred *cred, struct vm_map *map);
-MALLOC_DEFINE(M_MACTEMP, "mactemp", "MAC temporary label storage");
-
-/*
- * mac_static_policy_list holds a list of policy modules that are not
- * loaded while the system is "live", and cannot be unloaded. These
- * policies can be invoked without holding the busy count.
- *
- * mac_policy_list stores the list of dynamic policies. A busy count is
- * maintained for the list, stored in mac_policy_busy. The busy count
- * is protected by mac_policy_mtx; the list may be modified only
- * while the busy count is 0, requiring that the lock be held to
- * prevent new references to the list from being acquired. For almost
- * all operations, incrementing the busy count is sufficient to
- * guarantee consistency, as the list cannot be modified while the
- * busy count is elevated. For a few special operations involving a
- * change to the list of active policies, the mtx itself must be held.
- * A condition variable, mac_policy_cv, is used to signal potential
- * exclusive consumers that they should try to acquire the lock if a
- * first attempt at exclusive access fails.
- */
-#ifndef MAC_STATIC
-static struct mtx mac_policy_mtx;
-static struct cv mac_policy_cv;
-static int mac_policy_count;
-#endif
-struct mac_policy_list_head mac_policy_list;
-struct mac_policy_list_head mac_static_policy_list;
-
-/*
- * We manually invoke WITNESS_WARN() to allow Witness to generate
- * warnings even if we don't end up ever triggering the wait at
- * run-time. The consumer of the exclusive interface must not hold
- * any locks (other than potentially Giant) since we may sleep for
- * long (potentially indefinite) periods of time waiting for the
- * framework to become quiescent so that a policy list change may
- * be made.
- */
-void
-mac_policy_grab_exclusive(void)
-{
-
-#ifndef MAC_STATIC
- WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
- "mac_policy_grab_exclusive() at %s:%d", __FILE__, __LINE__);
- mtx_lock(&mac_policy_mtx);
- while (mac_policy_count != 0)
- cv_wait(&mac_policy_cv, &mac_policy_mtx);
-#endif
-}
-
-void
-mac_policy_assert_exclusive(void)
-{
-
-#ifndef MAC_STATIC
- mtx_assert(&mac_policy_mtx, MA_OWNED);
- KASSERT(mac_policy_count == 0,
- ("mac_policy_assert_exclusive(): not exclusive"));
-#endif
-}
-
-void
-mac_policy_release_exclusive(void)
-{
-
-#ifndef MAC_STATIC
- KASSERT(mac_policy_count == 0,
- ("mac_policy_release_exclusive(): not exclusive"));
- mtx_unlock(&mac_policy_mtx);
- cv_signal(&mac_policy_cv);
-#endif
-}
-
-void
-mac_policy_list_busy(void)
-{
-
-#ifndef MAC_STATIC
- mtx_lock(&mac_policy_mtx);
- mac_policy_count++;
- mtx_unlock(&mac_policy_mtx);
-#endif
-}
-
-int
-mac_policy_list_conditional_busy(void)
-{
-#ifndef MAC_STATIC
- int ret;
-
- mtx_lock(&mac_policy_mtx);
- if (!LIST_EMPTY(&mac_policy_list)) {
- mac_policy_count++;
- ret = 1;
- } else
- ret = 0;
- mtx_unlock(&mac_policy_mtx);
- return (ret);
-#else
- return (0);
-#endif
-}
-
-void
-mac_policy_list_unbusy(void)
-{
-
-#ifndef MAC_STATIC
- mtx_lock(&mac_policy_mtx);
- mac_policy_count--;
- KASSERT(mac_policy_count >= 0, ("MAC_POLICY_LIST_LOCK"));
- if (mac_policy_count == 0)
- cv_signal(&mac_policy_cv);
- mtx_unlock(&mac_policy_mtx);
-#endif
-}
-
-/*
- * Initialize the MAC subsystem, including appropriate SMP locks.
- */
-static void
-mac_init(void)
-{
-
- LIST_INIT(&mac_static_policy_list);
- LIST_INIT(&mac_policy_list);
-
-#ifndef MAC_STATIC
- mtx_init(&mac_policy_mtx, "mac_policy_mtx", NULL, MTX_DEF);
- cv_init(&mac_policy_cv, "mac_policy_cv");
-#endif
-}
-
-/*
- * For the purposes of modules that want to know if they were loaded
- * "early", set the mac_late flag once we've processed modules either
- * linked into the kernel, or loaded before the kernel startup.
- */
-static void
-mac_late_init(void)
-{
-
- mac_late = 1;
-}
-
-/*
- * After the policy list has changed, walk the list to update any global
- * flags. Currently, we support only one flag, and it's conditionally
- * defined; as a result, the entire function is conditional. Eventually,
- * the #else case might also iterate across the policies.
- */
-static void
-mac_policy_updateflags(void)
-{
-#ifndef MAC_ALWAYS_LABEL_MBUF
- struct mac_policy_conf *tmpc;
- int labelmbufs;
-
- mac_policy_assert_exclusive();
-
- labelmbufs = 0;
- LIST_FOREACH(tmpc, &mac_static_policy_list, mpc_list) {
- if (tmpc->mpc_loadtime_flags & MPC_LOADTIME_FLAG_LABELMBUFS)
- labelmbufs++;
- }
- LIST_FOREACH(tmpc, &mac_policy_list, mpc_list) {
- if (tmpc->mpc_loadtime_flags & MPC_LOADTIME_FLAG_LABELMBUFS)
- labelmbufs++;
- }
- mac_labelmbufs = (labelmbufs != 0);
-#endif
-}
-
-/*
- * Allow MAC policy modules to register during boot, etc.
- */
-int
-mac_policy_modevent(module_t mod, int type, void *data)
-{
- struct mac_policy_conf *mpc;
- int error;
-
- error = 0;
- mpc = (struct mac_policy_conf *) data;
-
-#ifdef MAC_STATIC
- if (mac_late) {
- printf("mac_policy_modevent: MAC_STATIC and late\n");
- return (EBUSY);
- }
-#endif
-
- switch (type) {
- case MOD_LOAD:
- if (mpc->mpc_loadtime_flags & MPC_LOADTIME_FLAG_NOTLATE &&
- mac_late) {
- printf("mac_policy_modevent: can't load %s policy "
- "after booting\n", mpc->mpc_name);
- error = EBUSY;
- break;
- }
- error = mac_policy_register(mpc);
- break;
- case MOD_UNLOAD:
- /* Don't unregister the module if it was never registered. */
- if ((mpc->mpc_runtime_flags & MPC_RUNTIME_FLAG_REGISTERED)
- != 0)
- error = mac_policy_unregister(mpc);
- else
- error = 0;
- break;
- default:
- break;
- }
-
- return (error);
-}
-
-static int
-mac_policy_register(struct mac_policy_conf *mpc)
-{
- struct mac_policy_conf *tmpc;
- int error, slot, static_entry;
-
- error = 0;
-
- /*
- * We don't technically need exclusive access while !mac_late,
- * but hold it for assertion consistency.
- */
- mac_policy_grab_exclusive();
-
- /*
- * If the module can potentially be unloaded, or we're loading
- * late, we have to stick it in the non-static list and pay
- * an extra performance overhead. Otherwise, we can pay a
- * light locking cost and stick it in the static list.
- */
- static_entry = (!mac_late &&
- !(mpc->mpc_loadtime_flags & MPC_LOADTIME_FLAG_UNLOADOK));
-
- if (static_entry) {
- LIST_FOREACH(tmpc, &mac_static_policy_list, mpc_list) {
- if (strcmp(tmpc->mpc_name, mpc->mpc_name) == 0) {
- error = EEXIST;
- goto out;
- }
- }
- } else {
- LIST_FOREACH(tmpc, &mac_policy_list, mpc_list) {
- if (strcmp(tmpc->mpc_name, mpc->mpc_name) == 0) {
- error = EEXIST;
- goto out;
- }
- }
- }
- if (mpc->mpc_field_off != NULL) {
- slot = ffs(mac_slot_offsets_free);
- if (slot == 0) {
- error = ENOMEM;
- goto out;
- }
- slot--;
- mac_slot_offsets_free &= ~(1 << slot);
- *mpc->mpc_field_off = slot;
- }
- mpc->mpc_runtime_flags |= MPC_RUNTIME_FLAG_REGISTERED;
-
- /*
- * If we're loading a MAC module after the framework has
- * initialized, it has to go into the dynamic list. If
- * we're loading it before we've finished initializing,
- * it can go into the static list with weaker locker
- * requirements.
- */
- if (static_entry)
- LIST_INSERT_HEAD(&mac_static_policy_list, mpc, mpc_list);
- else
- LIST_INSERT_HEAD(&mac_policy_list, mpc, mpc_list);
-
- /* Per-policy initialization. */
- if (mpc->mpc_ops->mpo_init != NULL)
- (*(mpc->mpc_ops->mpo_init))(mpc);
- mac_policy_updateflags();
-
- printf("Security policy loaded: %s (%s)\n", mpc->mpc_fullname,
- mpc->mpc_name);
-
-out:
- mac_policy_release_exclusive();
- return (error);
-}
-
-static int
-mac_policy_unregister(struct mac_policy_conf *mpc)
-{
-
- /*
- * If we fail the load, we may get a request to unload. Check
- * to see if we did the run-time registration, and if not,
- * silently succeed.
- */
- mac_policy_grab_exclusive();
- if ((mpc->mpc_runtime_flags & MPC_RUNTIME_FLAG_REGISTERED) == 0) {
- mac_policy_release_exclusive();
- return (0);
- }
-#if 0
- /*
- * Don't allow unloading modules with private data.
- */
- if (mpc->mpc_field_off != NULL) {
- MAC_POLICY_LIST_UNLOCK();
- return (EBUSY);
- }
>>> TRUNCATED FOR MAIL (1000 lines) <<<
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