freebsd-dev/sys/security/mac/mac_policy.h

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/*-
* Copyright (c) 1999, 2000, 2001, 2002 Robert N. M. Watson
* Copyright (c) 2001, 2002, 2003 Networks Associates Technology, Inc.
* All rights reserved.
*
* This software was developed by Robert Watson for the TrustedBSD Project.
*
* This software was developed for the FreeBSD Project in part by Network
* Associates Laboratories, 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.
*
* 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.
*
* $FreeBSD$
*/
/*
* Kernel interface for MAC policy modules.
*/
#ifndef _SYS_MAC_POLICY_H
#define _SYS_MAC_POLICY_H
/*-
* Pluggable access control policy definition structure.
*
* List of operations that are performed as part of the implementation
* of a MAC policy. Policy implementors declare operations with a
* mac_policy_ops structure, and using the MAC_POLICY_SET() macro.
* If an entry point is not declared, then then the policy will be ignored
* during evaluation of that event or check.
*
* Operations are sorted first by general class of operation, then
* alphabetically.
*/
struct acl;
struct componentname;
struct devfs_dirent;
struct ipq;
struct label;
struct mac_policy_conf;
struct mbuf;
struct mount;
struct pipe;
struct sbuf;
struct socket;
struct ucred;
struct uio;
struct vnode;
struct mac_policy_ops {
/*
* Policy module operations.
*/
void (*mpo_destroy)(struct mac_policy_conf *mpc);
void (*mpo_init)(struct mac_policy_conf *mpc);
/*
* General policy-directed security system call so that policies
* may implement new services without reserving explicit
* system call numbers.
*/
int (*mpo_syscall)(struct thread *td, int call, void *arg);
/*
* Label operations.
*/
void (*mpo_init_bpfdesc_label)(struct label *label);
void (*mpo_init_cred_label)(struct label *label);
void (*mpo_init_devfsdirent_label)(struct label *label);
void (*mpo_init_ifnet_label)(struct label *label);
int (*mpo_init_ipq_label)(struct label *label, int flag);
int (*mpo_init_mbuf_label)(struct label *label, int flag);
void (*mpo_init_mount_label)(struct label *label);
void (*mpo_init_mount_fs_label)(struct label *label);
int (*mpo_init_socket_label)(struct label *label, int flag);
int (*mpo_init_socket_peer_label)(struct label *label, int flag);
void (*mpo_init_pipe_label)(struct label *label);
void (*mpo_init_proc_label)(struct label *label);
void (*mpo_init_vnode_label)(struct label *label);
void (*mpo_destroy_bpfdesc_label)(struct label *label);
void (*mpo_destroy_cred_label)(struct label *label);
void (*mpo_destroy_devfsdirent_label)(struct label *label);
void (*mpo_destroy_ifnet_label)(struct label *label);
void (*mpo_destroy_ipq_label)(struct label *label);
void (*mpo_destroy_mbuf_label)(struct label *label);
void (*mpo_destroy_mount_label)(struct label *label);
void (*mpo_destroy_mount_fs_label)(struct label *label);
void (*mpo_destroy_socket_label)(struct label *label);
void (*mpo_destroy_socket_peer_label)(struct label *label);
void (*mpo_destroy_pipe_label)(struct label *label);
void (*mpo_destroy_proc_label)(struct label *label);
void (*mpo_destroy_vnode_label)(struct label *label);
Move MAC label storage for mbufs into m_tags from the m_pkthdr structure, returning some additional room in the first mbuf in a chain, and avoiding feature-specific contents in the mbuf header. To do this: - Modify mbuf_to_label() to extract the tag, returning NULL if not found. - Introduce mac_init_mbuf_tag() which does most of the work mac_init_mbuf() used to do, except on an m_tag rather than an mbuf. - Scale back mac_init_mbuf() to perform m_tag allocation and invoke mac_init_mbuf_tag(). - Replace mac_destroy_mbuf() with mac_destroy_mbuf_tag(), since m_tag's are now GC'd deep in the m_tag/mbuf code rather than at a higher level when mbufs are directly free()'d. - Add mac_copy_mbuf_tag() to support m_copy_pkthdr() and related notions. - Generally change all references to mbuf labels so that they use mbuf_to_label() rather than &mbuf->m_pkthdr.label. This required no changes in the MAC policies (yay!). - Tweak mbuf release routines to not call mac_destroy_mbuf(), tag destruction takes care of it for us now. - Remove MAC magic from m_copy_pkthdr() and m_move_pkthdr() -- the existing m_tag support does all this for us. Note that we can no longer just zero the m_tag list on the target mbuf, rather, we have to delete the chain because m_tag's will already be hung off freshly allocated mbuf's. - Tweak m_tag copying routines so that if we're copying a MAC m_tag, we don't do a binary copy, rather, we initialize the new storage and do a deep copy of the label. - Remove use of MAC_FLAG_INITIALIZED in a few bizarre places having to do with mbuf header copies previously. - When an mbuf is copied in ip_input(), we no longer need to explicitly copy the label because it will get handled by the m_tag code now. - No longer any weird handling of MAC labels in if_loop.c during header copies. - Add MPC_LOADTIME_FLAG_LABELMBUFS flag to Biba, MLS, mac_test. In mac_test, handle the label==NULL case, since it can be dynamically loaded. In order to improve performance with this change, introduce the notion of "lazy MAC label allocation" -- only allocate m_tag storage for MAC labels if we're running with a policy that uses MAC labels on mbufs. Policies declare this intent by setting the MPC_LOADTIME_FLAG_LABELMBUFS flag in their load-time flags field during declaration. Note: this opens up the possibility of post-boot policy modules getting back NULL slot entries even though they have policy invariants of non-NULL slot entries, as the policy might have been loaded after the mbuf was allocated, leaving the mbuf without label storage. Policies that cannot handle this case must be declared as NOTLATE, or must be modified. - mac_labelmbufs holds the current cumulative status as to whether any policies require mbuf labeling or not. This is updated whenever the active policy set changes by the function mac_policy_updateflags(). The function iterates the list and checks whether any have the flag set. Write access to this variable is protected by the policy list; read access is currently not protected for performance reasons. This might change if it causes problems. - Add MAC_POLICY_LIST_ASSERT_EXCLUSIVE() to permit the flags update function to assert appropriate locks. - This makes allocation in mac_init_mbuf() conditional on the flag. Reviewed by: sam Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-04-14 20:39:06 +00:00
void (*mpo_copy_mbuf_label)(struct label *src,
struct label *dest);
void (*mpo_copy_pipe_label)(struct label *src,
struct label *dest);
void (*mpo_copy_vnode_label)(struct label *src,
struct label *dest);
int (*mpo_externalize_cred_label)(struct label *label,
char *element_name, struct sbuf *sb, int *claimed);
int (*mpo_externalize_ifnet_label)(struct label *label,
char *element_name, struct sbuf *sb, int *claimed);
int (*mpo_externalize_pipe_label)(struct label *label,
char *element_name, struct sbuf *sb, int *claimed);
int (*mpo_externalize_socket_label)(struct label *label,
char *element_name, struct sbuf *sb, int *claimed);
int (*mpo_externalize_socket_peer_label)(struct label *label,
char *element_name, struct sbuf *sb, int *claimed);
int (*mpo_externalize_vnode_label)(struct label *label,
char *element_name, struct sbuf *sb, int *claimed);
int (*mpo_internalize_cred_label)(struct label *label,
char *element_name, char *element_data, int *claimed);
int (*mpo_internalize_ifnet_label)(struct label *label,
char *element_name, char *element_data, int *claimed);
int (*mpo_internalize_pipe_label)(struct label *label,
char *element_name, char *element_data, int *claimed);
int (*mpo_internalize_socket_label)(struct label *label,
char *element_name, char *element_data, int *claimed);
int (*mpo_internalize_vnode_label)(struct label *label,
char *element_name, char *element_data, int *claimed);
/*
* Labeling event operations: file system objects, and things that
* look a lot like file system objects.
*/
void (*mpo_associate_vnode_devfs)(struct mount *mp,
struct label *fslabel, struct devfs_dirent *de,
struct label *delabel, struct vnode *vp,
struct label *vlabel);
int (*mpo_associate_vnode_extattr)(struct mount *mp,
struct label *fslabel, struct vnode *vp,
struct label *vlabel);
void (*mpo_associate_vnode_singlelabel)(struct mount *mp,
struct label *fslabel, struct vnode *vp,
struct label *vlabel);
void (*mpo_create_devfs_device)(struct mount *mp, dev_t dev,
struct devfs_dirent *de, struct label *label);
void (*mpo_create_devfs_directory)(struct mount *mp, char *dirname,
int dirnamelen, struct devfs_dirent *de,
struct label *label);
void (*mpo_create_devfs_symlink)(struct ucred *cred,
struct mount *mp, struct devfs_dirent *dd,
struct label *ddlabel, struct devfs_dirent *de,
struct label *delabel);
int (*mpo_create_vnode_extattr)(struct ucred *cred,
struct mount *mp, struct label *fslabel,
struct vnode *dvp, struct label *dlabel,
struct vnode *vp, struct label *vlabel,
struct componentname *cnp);
void (*mpo_create_mount)(struct ucred *cred, struct mount *mp,
struct label *mntlabel, struct label *fslabel);
void (*mpo_create_root_mount)(struct ucred *cred, struct mount *mp,
struct label *mountlabel, struct label *fslabel);
void (*mpo_relabel_vnode)(struct ucred *cred, struct vnode *vp,
struct label *vnodelabel, struct label *label);
int (*mpo_setlabel_vnode_extattr)(struct ucred *cred,
struct vnode *vp, struct label *vlabel,
struct label *intlabel);
void (*mpo_update_devfsdirent)(struct mount *mp,
struct devfs_dirent *devfs_dirent,
struct label *direntlabel, struct vnode *vp,
struct label *vnodelabel);
/*
* Labeling event operations: IPC objects.
*/
void (*mpo_create_mbuf_from_socket)(struct socket *so,
struct label *socketlabel, struct mbuf *m,
struct label *mbuflabel);
void (*mpo_create_socket)(struct ucred *cred, struct socket *so,
struct label *socketlabel);
void (*mpo_create_socket_from_socket)(struct socket *oldsocket,
struct label *oldsocketlabel, struct socket *newsocket,
struct label *newsocketlabel);
void (*mpo_relabel_socket)(struct ucred *cred, struct socket *so,
struct label *oldlabel, struct label *newlabel);
void (*mpo_relabel_pipe)(struct ucred *cred, struct pipe *pipe,
struct label *oldlabel, struct label *newlabel);
void (*mpo_set_socket_peer_from_mbuf)(struct mbuf *mbuf,
struct label *mbuflabel, struct socket *so,
struct label *socketpeerlabel);
void (*mpo_set_socket_peer_from_socket)(struct socket *oldsocket,
struct label *oldsocketlabel, struct socket *newsocket,
struct label *newsocketpeerlabel);
void (*mpo_create_pipe)(struct ucred *cred, struct pipe *pipe,
struct label *pipelabel);
/*
* Labeling event operations: network objects.
*/
void (*mpo_create_bpfdesc)(struct ucred *cred, struct bpf_d *bpf_d,
struct label *bpflabel);
void (*mpo_create_ifnet)(struct ifnet *ifnet,
struct label *ifnetlabel);
void (*mpo_create_ipq)(struct mbuf *fragment,
struct label *fragmentlabel, struct ipq *ipq,
struct label *ipqlabel);
void (*mpo_create_datagram_from_ipq)
(struct ipq *ipq, struct label *ipqlabel,
struct mbuf *datagram, struct label *datagramlabel);
void (*mpo_create_fragment)(struct mbuf *datagram,
struct label *datagramlabel, struct mbuf *fragment,
struct label *fragmentlabel);
void (*mpo_create_mbuf_from_mbuf)(struct mbuf *oldmbuf,
struct label *oldlabel, struct mbuf *newmbuf,
struct label *newlabel);
void (*mpo_create_mbuf_linklayer)(struct ifnet *ifnet,
struct label *ifnetlabel, struct mbuf *mbuf,
struct label *mbuflabel);
void (*mpo_create_mbuf_from_bpfdesc)(struct bpf_d *bpf_d,
struct label *bpflabel, struct mbuf *mbuf,
struct label *mbuflabel);
void (*mpo_create_mbuf_from_ifnet)(struct ifnet *ifnet,
struct label *ifnetlabel, struct mbuf *mbuf,
struct label *mbuflabel);
void (*mpo_create_mbuf_multicast_encap)(struct mbuf *oldmbuf,
struct label *oldmbuflabel, struct ifnet *ifnet,
struct label *ifnetlabel, struct mbuf *newmbuf,
struct label *newmbuflabel);
void (*mpo_create_mbuf_netlayer)(struct mbuf *oldmbuf,
struct label *oldmbuflabel, struct mbuf *newmbuf,
struct label *newmbuflabel);
int (*mpo_fragment_match)(struct mbuf *fragment,
struct label *fragmentlabel, struct ipq *ipq,
struct label *ipqlabel);
void (*mpo_relabel_ifnet)(struct ucred *cred, struct ifnet *ifnet,
struct label *ifnetlabel, struct label *newlabel);
void (*mpo_update_ipq)(struct mbuf *fragment,
struct label *fragmentlabel, struct ipq *ipq,
struct label *ipqlabel);
/*
* Labeling event operations: processes.
*/
void (*mpo_create_cred)(struct ucred *parent_cred,
struct ucred *child_cred);
void (*mpo_execve_transition)(struct ucred *old, struct ucred *new,
struct vnode *vp, struct label *vnodelabel,
struct label *interpvnodelabel,
struct image_params *imgp, struct label *execlabel);
int (*mpo_execve_will_transition)(struct ucred *old,
struct vnode *vp, struct label *vnodelabel,
struct label *interpvnodelabel,
struct image_params *imgp, struct label *execlabel);
void (*mpo_create_proc0)(struct ucred *cred);
void (*mpo_create_proc1)(struct ucred *cred);
void (*mpo_relabel_cred)(struct ucred *cred,
struct label *newlabel);
void (*mpo_thread_userret)(struct thread *thread);
/*
* Access control checks.
*/
int (*mpo_check_bpfdesc_receive)(struct bpf_d *bpf_d,
struct label *bpflabel, struct ifnet *ifnet,
struct label *ifnetlabel);
int (*mpo_check_cred_relabel)(struct ucred *cred,
struct label *newlabel);
int (*mpo_check_cred_visible)(struct ucred *u1, struct ucred *u2);
int (*mpo_check_ifnet_relabel)(struct ucred *cred,
struct ifnet *ifnet, struct label *ifnetlabel,
struct label *newlabel);
int (*mpo_check_ifnet_transmit)(struct ifnet *ifnet,
struct label *ifnetlabel, struct mbuf *m,
struct label *mbuflabel);
int (*mpo_check_kenv_dump)(struct ucred *cred);
int (*mpo_check_kenv_get)(struct ucred *cred, char *name);
int (*mpo_check_kenv_set)(struct ucred *cred, char *name,
char *value);
int (*mpo_check_kenv_unset)(struct ucred *cred, char *name);
int (*mpo_check_kld_load)(struct ucred *cred, struct vnode *vp,
struct label *vlabel);
int (*mpo_check_kld_stat)(struct ucred *cred);
int (*mpo_check_kld_unload)(struct ucred *cred);
int (*mpo_check_mount_stat)(struct ucred *cred, struct mount *mp,
struct label *mntlabel);
int (*mpo_check_pipe_ioctl)(struct ucred *cred, struct pipe *pipe,
struct label *pipelabel, unsigned long cmd, void *data);
int (*mpo_check_pipe_poll)(struct ucred *cred, struct pipe *pipe,
struct label *pipelabel);
int (*mpo_check_pipe_read)(struct ucred *cred, struct pipe *pipe,
struct label *pipelabel);
int (*mpo_check_pipe_relabel)(struct ucred *cred,
struct pipe *pipe, struct label *pipelabel,
struct label *newlabel);
int (*mpo_check_pipe_stat)(struct ucred *cred, struct pipe *pipe,
struct label *pipelabel);
int (*mpo_check_pipe_write)(struct ucred *cred, struct pipe *pipe,
struct label *pipelabel);
int (*mpo_check_proc_debug)(struct ucred *cred,
struct proc *proc);
int (*mpo_check_proc_sched)(struct ucred *cred,
struct proc *proc);
int (*mpo_check_proc_signal)(struct ucred *cred,
struct proc *proc, int signum);
int (*mpo_check_socket_bind)(struct ucred *cred,
struct socket *so, struct label *socketlabel,
struct sockaddr *sockaddr);
int (*mpo_check_socket_connect)(struct ucred *cred,
struct socket *so, struct label *socketlabel,
struct sockaddr *sockaddr);
int (*mpo_check_socket_deliver)(struct socket *so,
struct label *socketlabel, struct mbuf *m,
struct label *mbuflabel);
int (*mpo_check_socket_listen)(struct ucred *cred,
struct socket *so, struct label *socketlabel);
int (*mpo_check_socket_receive)(struct ucred *cred,
struct socket *so, struct label *socketlabel);
int (*mpo_check_socket_relabel)(struct ucred *cred,
struct socket *so, struct label *socketlabel,
struct label *newlabel);
int (*mpo_check_socket_send)(struct ucred *cred,
struct socket *so, struct label *socketlabel);
int (*mpo_check_socket_visible)(struct ucred *cred,
struct socket *so, struct label *socketlabel);
int (*mpo_check_sysarch_ioperm)(struct ucred *cred);
int (*mpo_check_system_acct)(struct ucred *cred,
struct vnode *vp, struct label *vlabel);
int (*mpo_check_system_nfsd)(struct ucred *cred);
int (*mpo_check_system_reboot)(struct ucred *cred, int howto);
int (*mpo_check_system_settime)(struct ucred *cred);
int (*mpo_check_system_swapon)(struct ucred *cred,
struct vnode *vp, struct label *label);
int (*mpo_check_system_swapoff)(struct ucred *cred,
struct vnode *vp, struct label *label);
int (*mpo_check_system_sysctl)(struct ucred *cred, int *name,
u_int namelen, void *old, size_t *oldlenp, int inkernel,
void *new, size_t newlen);
int (*mpo_check_vnode_access)(struct ucred *cred,
struct vnode *vp, struct label *label, int acc_mode);
int (*mpo_check_vnode_chdir)(struct ucred *cred,
struct vnode *dvp, struct label *dlabel);
int (*mpo_check_vnode_chroot)(struct ucred *cred,
struct vnode *dvp, struct label *dlabel);
int (*mpo_check_vnode_create)(struct ucred *cred,
struct vnode *dvp, struct label *dlabel,
struct componentname *cnp, struct vattr *vap);
int (*mpo_check_vnode_delete)(struct ucred *cred,
struct vnode *dvp, struct label *dlabel,
struct vnode *vp, struct label *label,
struct componentname *cnp);
int (*mpo_check_vnode_deleteacl)(struct ucred *cred,
struct vnode *vp, struct label *label, acl_type_t type);
int (*mpo_check_vnode_exec)(struct ucred *cred, struct vnode *vp,
struct label *label, struct image_params *imgp,
struct label *execlabel);
int (*mpo_check_vnode_getacl)(struct ucred *cred,
struct vnode *vp, struct label *label, acl_type_t type);
int (*mpo_check_vnode_getextattr)(struct ucred *cred,
struct vnode *vp, struct label *label, int attrnamespace,
const char *name, struct uio *uio);
int (*mpo_check_vnode_link)(struct ucred *cred, struct vnode *dvp,
struct label *dlabel, struct vnode *vp,
struct label *label, struct componentname *cnp);
int (*mpo_check_vnode_lookup)(struct ucred *cred,
struct vnode *dvp, struct label *dlabel,
struct componentname *cnp);
int (*mpo_check_vnode_mmap)(struct ucred *cred, struct vnode *vp,
struct label *label, int prot);
void (*mpo_check_vnode_mmap_downgrade)(struct ucred *cred,
struct vnode *vp, struct label *label, int *prot);
int (*mpo_check_vnode_mprotect)(struct ucred *cred,
struct vnode *vp, struct label *label, int prot);
int (*mpo_check_vnode_open)(struct ucred *cred, struct vnode *vp,
struct label *label, int acc_mode);
int (*mpo_check_vnode_poll)(struct ucred *active_cred,
struct ucred *file_cred, struct vnode *vp,
struct label *label);
int (*mpo_check_vnode_read)(struct ucred *active_cred,
struct ucred *file_cred, struct vnode *vp,
struct label *label);
int (*mpo_check_vnode_readdir)(struct ucred *cred,
struct vnode *dvp, struct label *dlabel);
int (*mpo_check_vnode_readlink)(struct ucred *cred,
struct vnode *vp, struct label *label);
int (*mpo_check_vnode_relabel)(struct ucred *cred,
struct vnode *vp, struct label *vnodelabel,
struct label *newlabel);
int (*mpo_check_vnode_rename_from)(struct ucred *cred,
struct vnode *dvp, struct label *dlabel, struct vnode *vp,
struct label *label, struct componentname *cnp);
int (*mpo_check_vnode_rename_to)(struct ucred *cred,
struct vnode *dvp, struct label *dlabel, struct vnode *vp,
struct label *label, int samedir,
struct componentname *cnp);
int (*mpo_check_vnode_revoke)(struct ucred *cred,
struct vnode *vp, struct label *label);
int (*mpo_check_vnode_setacl)(struct ucred *cred,
struct vnode *vp, struct label *label, acl_type_t type,
struct acl *acl);
int (*mpo_check_vnode_setextattr)(struct ucred *cred,
struct vnode *vp, struct label *label, int attrnamespace,
const char *name, struct uio *uio);
int (*mpo_check_vnode_setflags)(struct ucred *cred,
struct vnode *vp, struct label *label, u_long flags);
int (*mpo_check_vnode_setmode)(struct ucred *cred,
struct vnode *vp, struct label *label, mode_t mode);
int (*mpo_check_vnode_setowner)(struct ucred *cred,
struct vnode *vp, struct label *label, uid_t uid,
gid_t gid);
int (*mpo_check_vnode_setutimes)(struct ucred *cred,
struct vnode *vp, struct label *label,
struct timespec atime, struct timespec mtime);
int (*mpo_check_vnode_stat)(struct ucred *active_cred,
struct ucred *file_cred, struct vnode *vp,
struct label *label);
int (*mpo_check_vnode_write)(struct ucred *active_cred,
struct ucred *file_cred, struct vnode *vp,
struct label *label);
};
struct mac_policy_conf {
char *mpc_name; /* policy name */
char *mpc_fullname; /* policy full name */
struct mac_policy_ops *mpc_ops; /* policy operations */
int mpc_loadtime_flags; /* flags */
int *mpc_field_off; /* security field */
int mpc_runtime_flags; /* flags */
LIST_ENTRY(mac_policy_conf) mpc_list; /* global list */
};
/* Flags for the mpc_loadtime_flags field. */
#define MPC_LOADTIME_FLAG_NOTLATE 0x00000001
#define MPC_LOADTIME_FLAG_UNLOADOK 0x00000002
Move MAC label storage for mbufs into m_tags from the m_pkthdr structure, returning some additional room in the first mbuf in a chain, and avoiding feature-specific contents in the mbuf header. To do this: - Modify mbuf_to_label() to extract the tag, returning NULL if not found. - Introduce mac_init_mbuf_tag() which does most of the work mac_init_mbuf() used to do, except on an m_tag rather than an mbuf. - Scale back mac_init_mbuf() to perform m_tag allocation and invoke mac_init_mbuf_tag(). - Replace mac_destroy_mbuf() with mac_destroy_mbuf_tag(), since m_tag's are now GC'd deep in the m_tag/mbuf code rather than at a higher level when mbufs are directly free()'d. - Add mac_copy_mbuf_tag() to support m_copy_pkthdr() and related notions. - Generally change all references to mbuf labels so that they use mbuf_to_label() rather than &mbuf->m_pkthdr.label. This required no changes in the MAC policies (yay!). - Tweak mbuf release routines to not call mac_destroy_mbuf(), tag destruction takes care of it for us now. - Remove MAC magic from m_copy_pkthdr() and m_move_pkthdr() -- the existing m_tag support does all this for us. Note that we can no longer just zero the m_tag list on the target mbuf, rather, we have to delete the chain because m_tag's will already be hung off freshly allocated mbuf's. - Tweak m_tag copying routines so that if we're copying a MAC m_tag, we don't do a binary copy, rather, we initialize the new storage and do a deep copy of the label. - Remove use of MAC_FLAG_INITIALIZED in a few bizarre places having to do with mbuf header copies previously. - When an mbuf is copied in ip_input(), we no longer need to explicitly copy the label because it will get handled by the m_tag code now. - No longer any weird handling of MAC labels in if_loop.c during header copies. - Add MPC_LOADTIME_FLAG_LABELMBUFS flag to Biba, MLS, mac_test. In mac_test, handle the label==NULL case, since it can be dynamically loaded. In order to improve performance with this change, introduce the notion of "lazy MAC label allocation" -- only allocate m_tag storage for MAC labels if we're running with a policy that uses MAC labels on mbufs. Policies declare this intent by setting the MPC_LOADTIME_FLAG_LABELMBUFS flag in their load-time flags field during declaration. Note: this opens up the possibility of post-boot policy modules getting back NULL slot entries even though they have policy invariants of non-NULL slot entries, as the policy might have been loaded after the mbuf was allocated, leaving the mbuf without label storage. Policies that cannot handle this case must be declared as NOTLATE, or must be modified. - mac_labelmbufs holds the current cumulative status as to whether any policies require mbuf labeling or not. This is updated whenever the active policy set changes by the function mac_policy_updateflags(). The function iterates the list and checks whether any have the flag set. Write access to this variable is protected by the policy list; read access is currently not protected for performance reasons. This might change if it causes problems. - Add MAC_POLICY_LIST_ASSERT_EXCLUSIVE() to permit the flags update function to assert appropriate locks. - This makes allocation in mac_init_mbuf() conditional on the flag. Reviewed by: sam Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-04-14 20:39:06 +00:00
#define MPC_LOADTIME_FLAG_LABELMBUFS 0x00000004
/* Flags for the mpc_runtime_flags field. */
#define MPC_RUNTIME_FLAG_REGISTERED 0x00000001
#define MAC_POLICY_SET(mpops, mpname, mpfullname, mpflags, privdata_wanted) \
static struct mac_policy_conf mpname##_mac_policy_conf = { \
#mpname, \
mpfullname, \
mpops, \
mpflags, \
privdata_wanted, \
0, \
}; \
static moduledata_t mpname##_mod = { \
#mpname, \
mac_policy_modevent, \
&mpname##_mac_policy_conf \
}; \
MODULE_DEPEND(mpname, kernel_mac_support, 1, 1, 1); \
DECLARE_MODULE(mpname, mpname##_mod, SI_SUB_MAC_POLICY, \
SI_ORDER_MIDDLE)
int mac_policy_modevent(module_t mod, int type, void *data);
#define LABEL_TO_SLOT(l, s) (l)->l_perpolicy[s]
#endif /* !_SYS_MAC_POLICY_H */