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authorrwatson <rwatson@FreeBSD.org>2006-12-28 20:52:02 +0000
committerrwatson <rwatson@FreeBSD.org>2006-12-28 20:52:02 +0000
commit4a9f23955f54f39d915cf9362bf2870bb64b1715 (patch)
tree53e8f56870b8285f7517c10466171ff5af5f7f81 /sys/security
parent3f705f77655e039b66a3fb2c37ac772b17f9a128 (diff)
downloadFreeBSD-src-4a9f23955f54f39d915cf9362bf2870bb64b1715.zip
FreeBSD-src-4a9f23955f54f39d915cf9362bf2870bb64b1715.tar.gz
Break contents of kern_mac.c out into two files following a repo-copy:
mac_framework.c Contains basic MAC Framework functions, policy registration, sysinits, etc. mac_syscalls.c Contains implementations of various MAC system calls, including ENOSYS stubs when compiling without options MAC. Obtained from: TrustedBSD Project
Diffstat (limited to 'sys/security')
-rw-r--r--sys/security/mac/mac_framework.c672
-rw-r--r--sys/security/mac/mac_syscalls.c537
2 files changed, 0 insertions, 1209 deletions
diff --git a/sys/security/mac/mac_framework.c b/sys/security/mac/mac_framework.c
index 7047db1..1b3b8f0 100644
--- a/sys/security/mac/mac_framework.c
+++ b/sys/security/mac/mac_framework.c
@@ -65,8 +65,6 @@
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
-#include "opt_mac.h"
-
#include <sys/param.h>
#include <sys/condvar.h>
#include <sys/extattr.h>
@@ -109,8 +107,6 @@ __FBSDID("$FreeBSD$");
#include <security/mac/mac_internal.h>
#include <security/mac/mac_policy.h>
-#ifdef MAC
-
/*
* Root sysctl node for all MAC and MAC policy controls.
*/
@@ -621,673 +617,5 @@ mac_check_structmac_consistent(struct mac *mac)
return (0);
}
-/*
- * MPSAFE
- */
-int
-__mac_get_pid(struct thread *td, struct __mac_get_pid_args *uap)
-{
- char *elements, *buffer;
- struct mac mac;
- struct proc *tproc;
- struct ucred *tcred;
- int error;
-
- error = copyin(uap->mac_p, &mac, sizeof(mac));
- if (error)
- return (error);
-
- error = mac_check_structmac_consistent(&mac);
- if (error)
- return (error);
-
- tproc = pfind(uap->pid);
- if (tproc == NULL)
- return (ESRCH);
-
- tcred = NULL; /* Satisfy gcc. */
- error = p_cansee(td, tproc);
- if (error == 0)
- tcred = crhold(tproc->p_ucred);
- PROC_UNLOCK(tproc);
- if (error)
- return (error);
-
- elements = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
- error = copyinstr(mac.m_string, elements, mac.m_buflen, NULL);
- if (error) {
- free(elements, M_MACTEMP);
- crfree(tcred);
- return (error);
- }
-
- buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
- error = mac_externalize_cred_label(tcred->cr_label, elements,
- buffer, mac.m_buflen);
- if (error == 0)
- error = copyout(buffer, mac.m_string, strlen(buffer)+1);
-
- free(buffer, M_MACTEMP);
- free(elements, M_MACTEMP);
- crfree(tcred);
- return (error);
-}
-
-/*
- * MPSAFE
- */
-int
-__mac_get_proc(struct thread *td, struct __mac_get_proc_args *uap)
-{
- char *elements, *buffer;
- struct mac mac;
- int error;
-
- error = copyin(uap->mac_p, &mac, sizeof(mac));
- if (error)
- return (error);
-
- error = mac_check_structmac_consistent(&mac);
- if (error)
- return (error);
-
- elements = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
- error = copyinstr(mac.m_string, elements, mac.m_buflen, NULL);
- if (error) {
- free(elements, M_MACTEMP);
- return (error);
- }
-
- buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
- error = mac_externalize_cred_label(td->td_ucred->cr_label,
- elements, buffer, mac.m_buflen);
- if (error == 0)
- error = copyout(buffer, mac.m_string, strlen(buffer)+1);
-
- free(buffer, M_MACTEMP);
- free(elements, M_MACTEMP);
- return (error);
-}
-
-/*
- * MPSAFE
- */
-int
-__mac_set_proc(struct thread *td, struct __mac_set_proc_args *uap)
-{
- struct ucred *newcred, *oldcred;
- struct label *intlabel;
- struct proc *p;
- struct mac mac;
- char *buffer;
- int error;
-
- error = copyin(uap->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);
- }
-
- intlabel = mac_cred_label_alloc();
- error = mac_internalize_cred_label(intlabel, buffer);
- free(buffer, M_MACTEMP);
- if (error)
- goto out;
-
- newcred = crget();
-
- p = td->td_proc;
- PROC_LOCK(p);
- oldcred = p->p_ucred;
-
- error = mac_check_cred_relabel(oldcred, intlabel);
- if (error) {
- PROC_UNLOCK(p);
- crfree(newcred);
- goto out;
- }
-
- setsugid(p);
- crcopy(newcred, oldcred);
- mac_relabel_cred(newcred, intlabel);
- p->p_ucred = newcred;
-
- /*
- * Grab additional reference for use while revoking mmaps, prior to
- * releasing the proc lock and sharing the cred.
- */
- crhold(newcred);
- PROC_UNLOCK(p);
-
- mac_cred_mmapped_drop_perms(td, newcred);
-
- crfree(newcred); /* Free revocation reference. */
- crfree(oldcred);
-
-out:
- mac_cred_label_free(intlabel);
- return (error);
-}
-
-/*
- * MPSAFE
- */
-int
-__mac_get_fd(struct thread *td, struct __mac_get_fd_args *uap)
-{
- char *elements, *buffer;
- struct label *intlabel;
- struct file *fp;
- struct mac mac;
- struct vnode *vp;
- struct pipe *pipe;
- struct socket *so;
- short label_type;
- int vfslocked, error;
-
- error = copyin(uap->mac_p, &mac, sizeof(mac));
- if (error)
- return (error);
-
- error = mac_check_structmac_consistent(&mac);
- if (error)
- return (error);
-
- elements = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
- error = copyinstr(mac.m_string, elements, mac.m_buflen, NULL);
- if (error) {
- free(elements, M_MACTEMP);
- return (error);
- }
-
- buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
- error = fget(td, uap->fd, &fp);
- if (error)
- goto out;
-
- label_type = fp->f_type;
- switch (fp->f_type) {
- case DTYPE_FIFO:
- case DTYPE_VNODE:
- vp = fp->f_vnode;
- intlabel = mac_vnode_label_alloc();
- vfslocked = VFS_LOCK_GIANT(vp->v_mount);
- vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
- mac_copy_vnode_label(vp->v_label, intlabel);
- VOP_UNLOCK(vp, 0, td);
- VFS_UNLOCK_GIANT(vfslocked);
- error = mac_externalize_vnode_label(intlabel, elements,
- buffer, mac.m_buflen);
- mac_vnode_label_free(intlabel);
- break;
-
- case DTYPE_PIPE:
- pipe = fp->f_data;
- intlabel = mac_pipe_label_alloc();
- PIPE_LOCK(pipe);
- mac_copy_pipe_label(pipe->pipe_pair->pp_label, intlabel);
- PIPE_UNLOCK(pipe);
- error = mac_externalize_pipe_label(intlabel, elements,
- buffer, mac.m_buflen);
- mac_pipe_label_free(intlabel);
- break;
-
- case DTYPE_SOCKET:
- so = fp->f_data;
- intlabel = mac_socket_label_alloc(M_WAITOK);
- NET_LOCK_GIANT();
- SOCK_LOCK(so);
- mac_copy_socket_label(so->so_label, intlabel);
- SOCK_UNLOCK(so);
- NET_UNLOCK_GIANT();
- error = mac_externalize_socket_label(intlabel, elements,
- buffer, mac.m_buflen);
- mac_socket_label_free(intlabel);
- break;
-
- default:
- error = EINVAL;
- }
- fdrop(fp, td);
- if (error == 0)
- error = copyout(buffer, mac.m_string, strlen(buffer)+1);
-
-out:
- free(buffer, M_MACTEMP);
- free(elements, M_MACTEMP);
- return (error);
-}
-
-/*
- * MPSAFE
- */
-int
-__mac_get_file(struct thread *td, struct __mac_get_file_args *uap)
-{
- char *elements, *buffer;
- struct nameidata nd;
- struct label *intlabel;
- struct mac mac;
- int vfslocked, error;
-
- error = copyin(uap->mac_p, &mac, sizeof(mac));
- if (error)
- return (error);
-
- error = mac_check_structmac_consistent(&mac);
- if (error)
- return (error);
-
- elements = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
- error = copyinstr(mac.m_string, elements, mac.m_buflen, NULL);
- if (error) {
- free(elements, M_MACTEMP);
- return (error);
- }
-
- buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
- NDINIT(&nd, LOOKUP, MPSAFE | LOCKLEAF | FOLLOW, UIO_USERSPACE,
- uap->path_p, td);
- error = namei(&nd);
- if (error)
- goto out;
-
- intlabel = mac_vnode_label_alloc();
- vfslocked = NDHASGIANT(&nd);
- mac_copy_vnode_label(nd.ni_vp->v_label, intlabel);
- error = mac_externalize_vnode_label(intlabel, elements, buffer,
- mac.m_buflen);
-
- NDFREE(&nd, 0);
- VFS_UNLOCK_GIANT(vfslocked);
- mac_vnode_label_free(intlabel);
- if (error == 0)
- error = copyout(buffer, mac.m_string, strlen(buffer)+1);
-
-out:
- free(buffer, M_MACTEMP);
- free(elements, M_MACTEMP);
-
- return (error);
-}
-
-/*
- * MPSAFE
- */
-int
-__mac_get_link(struct thread *td, struct __mac_get_link_args *uap)
-{
- char *elements, *buffer;
- struct nameidata nd;
- struct label *intlabel;
- struct mac mac;
- int vfslocked, error;
-
- error = copyin(uap->mac_p, &mac, sizeof(mac));
- if (error)
- return (error);
-
- error = mac_check_structmac_consistent(&mac);
- if (error)
- return (error);
-
- elements = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
- error = copyinstr(mac.m_string, elements, mac.m_buflen, NULL);
- if (error) {
- free(elements, M_MACTEMP);
- return (error);
- }
-
- buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
- NDINIT(&nd, LOOKUP, MPSAFE | LOCKLEAF | NOFOLLOW, UIO_USERSPACE,
- uap->path_p, td);
- error = namei(&nd);
- if (error)
- goto out;
-
- intlabel = mac_vnode_label_alloc();
- vfslocked = NDHASGIANT(&nd);
- mac_copy_vnode_label(nd.ni_vp->v_label, intlabel);
- error = mac_externalize_vnode_label(intlabel, elements, buffer,
- mac.m_buflen);
- NDFREE(&nd, 0);
- VFS_UNLOCK_GIANT(vfslocked);
- mac_vnode_label_free(intlabel);
-
- if (error == 0)
- error = copyout(buffer, mac.m_string, strlen(buffer)+1);
-
-out:
- free(buffer, M_MACTEMP);
- free(elements, M_MACTEMP);
-
- return (error);
-}
-
-/*
- * MPSAFE
- */
-int
-__mac_set_fd(struct thread *td, struct __mac_set_fd_args *uap)
-{
- struct label *intlabel;
- struct pipe *pipe;
- struct socket *so;
- struct file *fp;
- struct mount *mp;
- struct vnode *vp;
- struct mac mac;
- char *buffer;
- int error, vfslocked;
-
- error = copyin(uap->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);
- }
-
- error = fget(td, uap->fd, &fp);
- if (error)
- goto out;
-
- switch (fp->f_type) {
- case DTYPE_FIFO:
- case DTYPE_VNODE:
- intlabel = mac_vnode_label_alloc();
- error = mac_internalize_vnode_label(intlabel, buffer);
- if (error) {
- mac_vnode_label_free(intlabel);
- break;
- }
- vp = fp->f_vnode;
- vfslocked = VFS_LOCK_GIANT(vp->v_mount);
- error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
- if (error != 0) {
- VFS_UNLOCK_GIANT(vfslocked);
- mac_vnode_label_free(intlabel);
- break;
- }
- vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
- error = vn_setlabel(vp, intlabel, td->td_ucred);
- VOP_UNLOCK(vp, 0, td);
- vn_finished_write(mp);
- VFS_UNLOCK_GIANT(vfslocked);
- mac_vnode_label_free(intlabel);
- break;
-
- case DTYPE_PIPE:
- intlabel = mac_pipe_label_alloc();
- error = mac_internalize_pipe_label(intlabel, buffer);
- if (error == 0) {
- pipe = fp->f_data;
- PIPE_LOCK(pipe);
- error = mac_pipe_label_set(td->td_ucred,
- pipe->pipe_pair, intlabel);
- PIPE_UNLOCK(pipe);
- }
- mac_pipe_label_free(intlabel);
- break;
-
- case DTYPE_SOCKET:
- intlabel = mac_socket_label_alloc(M_WAITOK);
- error = mac_internalize_socket_label(intlabel, buffer);
- if (error == 0) {
- so = fp->f_data;
- NET_LOCK_GIANT();
- error = mac_socket_label_set(td->td_ucred, so,
- intlabel);
- NET_UNLOCK_GIANT();
- }
- mac_socket_label_free(intlabel);
- break;
-
- default:
- error = EINVAL;
- }
- fdrop(fp, td);
-out:
- free(buffer, M_MACTEMP);
- return (error);
-}
-
-/*
- * MPSAFE
- */
-int
-__mac_set_file(struct thread *td, struct __mac_set_file_args *uap)
-{
- struct label *intlabel;
- struct nameidata nd;
- struct mount *mp;
- struct mac mac;
- char *buffer;
- int vfslocked, error;
-
- error = copyin(uap->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);
- }
-
- intlabel = mac_vnode_label_alloc();
- error = mac_internalize_vnode_label(intlabel, buffer);
- free(buffer, M_MACTEMP);
- if (error)
- goto out;
-
- NDINIT(&nd, LOOKUP, MPSAFE | LOCKLEAF | FOLLOW, UIO_USERSPACE,
- uap->path_p, td);
- error = namei(&nd);
- vfslocked = NDHASGIANT(&nd);
- if (error == 0) {
- error = vn_start_write(nd.ni_vp, &mp, V_WAIT | PCATCH);
- if (error == 0) {
- error = vn_setlabel(nd.ni_vp, intlabel,
- td->td_ucred);
- vn_finished_write(mp);
- }
- }
-
- NDFREE(&nd, 0);
- VFS_UNLOCK_GIANT(vfslocked);
-out:
- mac_vnode_label_free(intlabel);
- return (error);
-}
-
-/*
- * MPSAFE
- */
-int
-__mac_set_link(struct thread *td, struct __mac_set_link_args *uap)
-{
- struct label *intlabel;
- struct nameidata nd;
- struct mount *mp;
- struct mac mac;
- char *buffer;
- int vfslocked, error;
-
- error = copyin(uap->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);
- }
-
- intlabel = mac_vnode_label_alloc();
- error = mac_internalize_vnode_label(intlabel, buffer);
- free(buffer, M_MACTEMP);
- if (error)
- goto out;
-
- NDINIT(&nd, LOOKUP, MPSAFE | LOCKLEAF | NOFOLLOW, UIO_USERSPACE,
- uap->path_p, td);
- error = namei(&nd);
- vfslocked = NDHASGIANT(&nd);
- if (error == 0) {
- error = vn_start_write(nd.ni_vp, &mp, V_WAIT | PCATCH);
- if (error == 0) {
- error = vn_setlabel(nd.ni_vp, intlabel,
- td->td_ucred);
- vn_finished_write(mp);
- }
- }
-
- NDFREE(&nd, 0);
- VFS_UNLOCK_GIANT(vfslocked);
-out:
- mac_vnode_label_free(intlabel);
- return (error);
-}
-
-/*
- * MPSAFE
- */
-int
-mac_syscall(struct thread *td, struct mac_syscall_args *uap)
-{
- struct mac_policy_conf *mpc;
- char target[MAC_MAX_POLICY_NAME];
- int entrycount, error;
-
- error = copyinstr(uap->policy, target, sizeof(target), NULL);
- if (error)
- return (error);
-
- error = ENOSYS;
- LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) {
- if (strcmp(mpc->mpc_name, target) == 0 &&
- mpc->mpc_ops->mpo_syscall != NULL) {
- error = mpc->mpc_ops->mpo_syscall(td,
- uap->call, uap->arg);
- goto out;
- }
- }
-
- if ((entrycount = mac_policy_list_conditional_busy()) != 0) {
- LIST_FOREACH(mpc, &mac_policy_list, mpc_list) {
- if (strcmp(mpc->mpc_name, target) == 0 &&
- mpc->mpc_ops->mpo_syscall != NULL) {
- error = mpc->mpc_ops->mpo_syscall(td,
- uap->call, uap->arg);
- break;
- }
- }
- mac_policy_list_unbusy();
- }
-out:
- return (error);
-}
-
SYSINIT(mac, SI_SUB_MAC, SI_ORDER_FIRST, mac_init, NULL);
SYSINIT(mac_late, SI_SUB_MAC_LATE, SI_ORDER_FIRST, mac_late_init, NULL);
-
-#else /* !MAC */
-
-int
-__mac_get_pid(struct thread *td, struct __mac_get_pid_args *uap)
-{
-
- return (ENOSYS);
-}
-
-int
-__mac_get_proc(struct thread *td, struct __mac_get_proc_args *uap)
-{
-
- return (ENOSYS);
-}
-
-int
-__mac_set_proc(struct thread *td, struct __mac_set_proc_args *uap)
-{
-
- return (ENOSYS);
-}
-
-int
-__mac_get_fd(struct thread *td, struct __mac_get_fd_args *uap)
-{
-
- return (ENOSYS);
-}
-
-int
-__mac_get_file(struct thread *td, struct __mac_get_file_args *uap)
-{
-
- return (ENOSYS);
-}
-
-int
-__mac_get_link(struct thread *td, struct __mac_get_link_args *uap)
-{
-
- return (ENOSYS);
-}
-
-int
-__mac_set_fd(struct thread *td, struct __mac_set_fd_args *uap)
-{
-
- return (ENOSYS);
-}
-
-int
-__mac_set_file(struct thread *td, struct __mac_set_file_args *uap)
-{
-
- return (ENOSYS);
-}
-
-int
-__mac_set_link(struct thread *td, struct __mac_set_link_args *uap)
-{
-
- return (ENOSYS);
-}
-
-int
-mac_syscall(struct thread *td, struct mac_syscall_args *uap)
-{
-
- return (ENOSYS);
-}
-
-#endif /* !MAC */
diff --git a/sys/security/mac/mac_syscalls.c b/sys/security/mac/mac_syscalls.c
index 7047db1..d5aa2b8 100644
--- a/sys/security/mac/mac_syscalls.c
+++ b/sys/security/mac/mac_syscalls.c
@@ -38,30 +38,6 @@
* SUCH DAMAGE.
*/
-/*-
- * Framework for extensible kernel access control. This file contains core
- * kernel infrastructure for the TrustedBSD MAC Framework, including policy
- * registration, versioning, locking, error composition operator, and system
- * calls.
- *
- * The MAC Framework implements three programming interfaces:
- *
- * - The kernel MAC interface, defined in mac_framework.h, and invoked
- * throughout the kernel to request security decisions, notify of security
- * related events, etc.
- *
- * - The MAC policy module interface, defined in mac_policy.h, which is
- * implemented by MAC policy modules and invoked by the MAC Framework to
- * forward kernel security requests and notifications to policy modules.
- *
- * - The user MAC API, defined in mac.h, which allows user programs to query
- * and set label state on objects.
- *
- * The majority of the MAC Framework implementation may be found in
- * src/sys/security/mac. Sample policy modules may be found in
- * src/sys/security/mac_*.
- */
-
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
@@ -112,516 +88,6 @@ __FBSDID("$FreeBSD$");
#ifdef MAC
/*
- * Root sysctl node for all MAC and MAC policy controls.
- */
-SYSCTL_NODE(_security, OID_AUTO, mac, CTLFLAG_RW, 0,
- "TrustedBSD MAC policy controls");
-
-/*
- * Declare that the kernel provides MAC support, version 3 (FreeBSD 7.x).
- * This permits modules to refuse to be loaded if the necessary support isn't
- * present, even if it's pre-boot.
- */
-#define MAC_VERSION 3
-static unsigned int mac_version = MAC_VERSION;
-
-MODULE_VERSION(kernel_mac_support, MAC_VERSION);
-SYSCTL_UINT(_security_mac, OID_AUTO, version, CTLFLAG_RD, &mac_version, 0,
- "");
-
-/*
- * Labels consist of a indexed set of "slots", which are allocated policies
- * as required. The MAC Framework maintains a bitmask of slots allocated so
- * far to prevent reuse. Slots cannot be reused, as the MAC Framework
- * guarantees that newly allocated slots in labels will be NULL unless
- * otherwise initialized, and because we do not have a mechanism to garbage
- * collect slots on policy unload. As labeled policies tend to be statically
- * loaded during boot, and not frequently unloaded and reloaded, this is not
- * generally an issue.
- */
-#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?
- *
- * In the future, we may want to allow objects to request labeling on a per-
- * object type basis, rather than globally for all objects.
- */
-#ifndef MAC_ALWAYS_LABEL_MBUF
-int mac_labelmbufs = 0;
-#endif
-
-static int mac_policy_register(struct mac_policy_conf *mpc);
-static int mac_policy_unregister(struct mac_policy_conf *mpc);
-
-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.
- *
- * This design intentionally avoids fairness, and may starve attempts to
- * acquire an exclusive lock on a busy system. This is required because we
- * do not ever want acquiring a read reference to perform an unbounded length
- * sleep. Read references are acquired in ithreads, network isrs, etc, and
- * any unbounded blocking could lead quickly to deadlock.
- *
- * Another reason for never blocking on read references is that the MAC
- * Framework may recurse: if a policy calls a VOP, for example, this might
- * lead to vnode life cycle operations (such as init/destroy).
- *
- * If the kernel option MAC_STATIC has been compiled in, all locking becomes
- * a no-op, and the global list of policies is not allowed to change after
- * early boot.
- */
-#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
- if (!mac_late)
- return;
-
- 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
- if (!mac_late)
- return;
-
- 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
- if (!mac_late)
- return;
-
- 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
- if (!mac_late)
- return;
-
- 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;
-
- if (!mac_late)
- return (1);
-
- 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
- if (!mac_late)
- return (1);
-
- return (1);
-#endif
-}
-
-void
-mac_policy_list_unbusy(void)
-{
-
-#ifndef MAC_STATIC
- if (!mac_late)
- return;
-
- 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);
- mac_labelzone_init();
-
-#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:
- error = EOPNOTSUPP;
- 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. Currently, this takes place under the
- * exclusive lock, so policies must not sleep in their init method.
- * In the future, we may want to separate "init" from "start", with
- * "init" occuring without the lock held. Likewise, on tear-down,
- * breaking out "stop" from "destroy".
- */
- 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);
- }
-#endif
- /*
- * Only allow the unload to proceed if the module is unloadable by
- * its own definition.
- */
- if ((mpc->mpc_loadtime_flags & MPC_LOADTIME_FLAG_UNLOADOK) == 0) {
- mac_policy_release_exclusive();
- return (EBUSY);
- }
- if (mpc->mpc_ops->mpo_destroy != NULL)
- (*(mpc->mpc_ops->mpo_destroy))(mpc);
-
- LIST_REMOVE(mpc, mpc_list);
- mpc->mpc_runtime_flags &= ~MPC_RUNTIME_FLAG_REGISTERED;
- mac_policy_updateflags();
-
- mac_policy_release_exclusive();
-
- printf("Security policy unload: %s (%s)\n", mpc->mpc_fullname,
- mpc->mpc_name);
-
- return (0);
-}
-
-/*
- * Define an error value precedence, and given two arguments, selects the
- * value with the higher precedence.
- */
-int
-mac_error_select(int error1, int error2)
-{
-
- /* Certain decision-making errors take top priority. */
- if (error1 == EDEADLK || error2 == EDEADLK)
- return (EDEADLK);
-
- /* Invalid arguments should be reported where possible. */
- if (error1 == EINVAL || error2 == EINVAL)
- return (EINVAL);
-
- /* Precedence goes to "visibility", with both process and file. */
- if (error1 == ESRCH || error2 == ESRCH)
- return (ESRCH);
-
- if (error1 == ENOENT || error2 == ENOENT)
- return (ENOENT);
-
- /* Precedence goes to DAC/MAC protections. */
- if (error1 == EACCES || error2 == EACCES)
- return (EACCES);
-
- /* Precedence goes to privilege. */
- if (error1 == EPERM || error2 == EPERM)
- return (EPERM);
-
- /* Precedence goes to error over success; otherwise, arbitrary. */
- if (error1 != 0)
- return (error1);
- return (error2);
-}
-
-void
-mac_init_label(struct label *label)
-{
-
- bzero(label, sizeof(*label));
- label->l_flags = MAC_FLAG_INITIALIZED;
-}
-
-void
-mac_destroy_label(struct label *label)
-{
-
- KASSERT(label->l_flags & MAC_FLAG_INITIALIZED,
- ("destroying uninitialized label"));
-
- bzero(label, sizeof(*label));
- /* implicit: label->l_flags &= ~MAC_FLAG_INITIALIZED; */
-}
-
-int
-mac_check_structmac_consistent(struct mac *mac)
-{
-
- if (mac->m_buflen < 0 ||
- mac->m_buflen > MAC_MAX_LABEL_BUF_LEN)
- return (EINVAL);
-
- return (0);
-}
-
-/*
* MPSAFE
*/
int
@@ -1215,9 +681,6 @@ out:
return (error);
}
-SYSINIT(mac, SI_SUB_MAC, SI_ORDER_FIRST, mac_init, NULL);
-SYSINIT(mac_late, SI_SUB_MAC_LATE, SI_ORDER_FIRST, mac_late_init, NULL);
-
#else /* !MAC */
int
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