diff options
Diffstat (limited to 'sys/security/mac_bsdextended/mac_bsdextended.c')
-rw-r--r-- | sys/security/mac_bsdextended/mac_bsdextended.c | 749 |
1 files changed, 749 insertions, 0 deletions
diff --git a/sys/security/mac_bsdextended/mac_bsdextended.c b/sys/security/mac_bsdextended/mac_bsdextended.c new file mode 100644 index 0000000..f0f6cee --- /dev/null +++ b/sys/security/mac_bsdextended/mac_bsdextended.c @@ -0,0 +1,749 @@ +/*- + * Copyright (c) 1999, 2000, 2001, 2002 Robert N. M. Watson + * Copyright (c) 2001, 2002 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 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 names of the authors 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. + * + * $FreeBSD$ + */ +/* + * Developed by the TrustedBSD Project. + * "BSD Extended" MAC policy, allowing the administrator to impose + * mandatory rules regarding users and some system objects. + * + * XXX: Much locking support required here. + */ + +#include <sys/types.h> +#include <sys/param.h> +#include <sys/acl.h> +#include <sys/conf.h> +#include <sys/kernel.h> +#include <sys/mac.h> +#include <sys/malloc.h> +#include <sys/mount.h> +#include <sys/proc.h> +#include <sys/systm.h> +#include <sys/sysproto.h> +#include <sys/sysent.h> +#include <sys/vnode.h> +#include <sys/file.h> +#include <sys/socket.h> +#include <sys/socketvar.h> +#include <sys/sysctl.h> + +#include <net/bpfdesc.h> +#include <net/if.h> +#include <net/if_types.h> +#include <net/if_var.h> + +#include <vm/vm.h> + +#include <sys/mac_policy.h> + +#include <security/mac_bsdextended/mac_bsdextended.h> + +SYSCTL_DECL(_security_mac); + +SYSCTL_NODE(_security_mac, OID_AUTO, bsdextended, CTLFLAG_RW, 0, + "TrustedBSD extended BSD MAC policy controls"); + +static int mac_bsdextended_enabled = 1; +SYSCTL_INT(_security_mac_bsdextended, OID_AUTO, enabled, CTLFLAG_RW, + &mac_bsdextended_enabled, 0, "Enforce extended BSD policy"); +TUNABLE_INT("security.mac.bsdextended.enabled", &mac_bsdextended_enabled); + +MALLOC_DEFINE(M_MACBSDEXTENDED, "mac_bsdextended", "BSD Extended MAC rule"); + +#define MAC_BSDEXTENDED_MAXRULES 250 +static struct mac_bsdextended_rule *rules[MAC_BSDEXTENDED_MAXRULES]; +static int rule_count = 0; +static int rule_slots = 0; + +SYSCTL_INT(_security_mac_bsdextended, OID_AUTO, rule_count, CTLFLAG_RD, + &rule_count, 0, "Number of defined rules\n"); +SYSCTL_INT(_security_mac_bsdextended, OID_AUTO, rule_slots, CTLFLAG_RD, + &rule_slots, 0, "Number of used rule slots\n"); + +static int mac_bsdextended_debugging; +SYSCTL_INT(_security_mac_bsdextended, OID_AUTO, debugging, CTLFLAG_RW, + &mac_bsdextended_debugging, 0, "Enable debugging on failure"); + +static int +mac_bsdextended_rule_valid(struct mac_bsdextended_rule *rule) +{ + + if ((rule->mbr_subject.mbi_flags | MBI_BITS) != MBI_BITS) + return (EINVAL); + + if ((rule->mbr_object.mbi_flags | MBI_BITS) != MBI_BITS) + return (EINVAL); + + if ((rule->mbr_mode | VALLPERM) != VALLPERM) + return (EINVAL); + + return (0); +} + +static int +sysctl_rule(SYSCTL_HANDLER_ARGS) +{ + struct mac_bsdextended_rule temprule, *ruleptr; + u_int namelen; + int error, index, *name; + + name = (int *)arg1; + namelen = arg2; + + /* printf("bsdextended sysctl handler (namelen %d)\n", namelen); */ + + if (namelen != 1) + return (EINVAL); + + index = name[0]; + if (index < 0 || index > rule_slots + 1) + return (ENOENT); + if (rule_slots >= MAC_BSDEXTENDED_MAXRULES) + return (ENOENT); + + if (req->oldptr) { + if (rules[index] == NULL) + return (ENOENT); + + error = SYSCTL_OUT(req, rules[index], sizeof(*rules[index])); + if (error) + return (error); + } + + if (req->newptr) { + if (req->newlen == 0) { + /* printf("deletion\n"); */ + ruleptr = rules[index]; + if (ruleptr == NULL) + return (ENOENT); + rule_count--; + rules[index] = NULL; + FREE(ruleptr, M_MACBSDEXTENDED); + return(0); + } + error = SYSCTL_IN(req, &temprule, sizeof(temprule)); + if (error) + return (error); + + error = mac_bsdextended_rule_valid(&temprule); + if (error) + return (error); + + if (rules[index] == NULL) { + /* printf("addition\n"); */ + MALLOC(ruleptr, struct mac_bsdextended_rule *, + sizeof(*ruleptr), M_MACBSDEXTENDED, M_WAITOK | + M_ZERO); + *ruleptr = temprule; + rules[index] = ruleptr; + if (index+1 > rule_slots) + rule_slots = index+1; + rule_count++; + } else { + /* printf("replacement\n"); */ + *rules[index] = temprule; + } + } + + return (0); +} + +SYSCTL_NODE(_security_mac_bsdextended, OID_AUTO, rules, + CTLFLAG_RW, sysctl_rule, "BSD extended MAC rules"); + +static void +mac_bsdextended_init(struct mac_policy_conf *mpc) +{ + + /* Initialize ruleset lock. */ + /* Register dynamic sysctl's for rules. */ +} + +static void +mac_bsdextended_destroy(struct mac_policy_conf *mpc) +{ + + /* Tear down sysctls. */ + /* Destroy ruleset lock. */ +} + +static int +mac_bsdextended_rulecheck(struct mac_bsdextended_rule *rule, + struct ucred *cred, uid_t object_uid, gid_t object_gid, mode_t acc_mode) +{ + int match; + + /* + * Is there a subject match? + */ + if (rule->mbr_subject.mbi_flags & MBI_UID_DEFINED) { + match = (rule->mbr_subject.mbi_uid == cred->cr_uid || + rule->mbr_subject.mbi_uid == cred->cr_ruid || + rule->mbr_subject.mbi_uid == cred->cr_svuid); + + if (rule->mbr_subject.mbi_flags & MBI_NEGATED) + match = !match; + + if (!match) + return (0); + } + + if (rule->mbr_subject.mbi_flags & MBI_GID_DEFINED) { + match = (groupmember(rule->mbr_subject.mbi_gid, cred) || + rule->mbr_subject.mbi_gid == cred->cr_rgid || + rule->mbr_subject.mbi_gid == cred->cr_svgid); + + if (rule->mbr_subject.mbi_flags & MBI_NEGATED) + match = !match; + + if (!match) + return (0); + } + + /* + * Is there an object match? + */ + if (rule->mbr_object.mbi_flags & MBI_UID_DEFINED) { + match = (rule->mbr_object.mbi_uid == object_uid); + + if (rule->mbr_object.mbi_flags & MBI_NEGATED) + match = !match; + + if (!match) + return (0); + } + + if (rule->mbr_object.mbi_flags & MBI_GID_DEFINED) { + match = (rule->mbr_object.mbi_gid == object_gid); + + if (rule->mbr_object.mbi_flags & MBI_NEGATED) + match = !match; + + if (!match) + return (0); + } + + /* + * Is the access permitted? + */ + if ((rule->mbr_mode & acc_mode) != acc_mode) { + if (mac_bsdextended_debugging) + printf("mac_bsdextended: %d:%d request %d on %d:%d" + " fails\n", cred->cr_ruid, cred->cr_rgid, + acc_mode, object_uid, object_gid); + return (EACCES); + } + + return (0); +} + +static int +mac_bsdextended_check(struct ucred *cred, uid_t object_uid, gid_t object_gid, + mode_t acc_mode) +{ + int error, i; + + for (i = 0; i < rule_slots; i++) { + if (rules[i] == NULL) + continue; + + error = mac_bsdextended_rulecheck(rules[i], cred, object_uid, + object_gid, acc_mode); + if (error) + return (error); + } + + return (0); +} + +static int +mac_bsdextended_check_vnode_access(struct ucred *cred, struct vnode *vp, + struct label *label, mode_t flags) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, flags)); +} + +static int +mac_bsdextended_check_vnode_chdir(struct ucred *cred, struct vnode *dvp, + struct label *dlabel) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(dvp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VEXEC)); +} + +static int +mac_bsdextended_check_vnode_chroot(struct ucred *cred, struct vnode *dvp, + struct label *dlabel) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(dvp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VEXEC)); +} + +static int +mac_bsdextended_check_create_vnode(struct ucred *cred, struct vnode *dvp, + struct label *dlabel, struct componentname *cnp, struct vattr *vap) +{ + struct vattr dvap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(dvp, &dvap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, dvap.va_uid, dvap.va_gid, VWRITE)); +} + +static int +mac_bsdextended_check_vnode_delete(struct ucred *cred, struct vnode *dvp, + struct label *dlabel, struct vnode *vp, struct label *label, + struct componentname *cnp) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(dvp, &vap, cred, curthread); + if (error) + return (error); + error = mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VWRITE); + if (error) + return (error); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VWRITE)); +} + +static int +mac_bsdextended_check_vnode_deleteacl(struct ucred *cred, struct vnode *vp, + struct label *label, acl_type_t type) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VADMIN)); +} + +static int +mac_bsdextended_check_vnode_exec(struct ucred *cred, struct vnode *vp, + struct label *label) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, + VREAD|VEXEC)); +} + +static int +mac_bsdextended_check_vnode_getacl(struct ucred *cred, struct vnode *vp, + struct label *label, acl_type_t type) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VSTAT)); +} + +static int +mac_bsdextended_check_vnode_getextattr(struct ucred *cred, struct vnode *vp, + struct label *label, int attrnamespace, const char *name, struct uio *uio) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VREAD)); +} + +static int +mac_bsdextended_check_vnode_lookup(struct ucred *cred, struct vnode *dvp, + struct label *dlabel, struct componentname *cnp) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(dvp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VEXEC)); +} + +static int +mac_bsdextended_check_vnode_open(struct ucred *cred, struct vnode *vp, + struct label *filelabel, mode_t acc_mode) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, acc_mode)); +} + +static int +mac_bsdextended_check_vnode_readdir(struct ucred *cred, struct vnode *dvp, + struct label *dlabel) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(dvp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VREAD)); +} + +static int +mac_bsdextended_check_vnode_readdlink(struct ucred *cred, struct vnode *vp, + struct label *label) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VREAD)); +} + +static int +mac_bsdextended_check_vnode_rename_from(struct ucred *cred, struct vnode *dvp, + struct label *dlabel, struct vnode *vp, struct label *label, + struct componentname *cnp) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(dvp, &vap, cred, curthread); + if (error) + return (error); + error = mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VWRITE); + if (error) + return (error); + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + error = mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VWRITE); + + return (error); +} + +static int +mac_bsdextended_check_vnode_rename_to(struct ucred *cred, struct vnode *dvp, + struct label *dlabel, struct vnode *vp, struct label *label, int samedir, + struct componentname *cnp) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(dvp, &vap, cred, curthread); + if (error) + return (error); + error = mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VWRITE); + if (error) + return (error); + + if (vp != NULL) { + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + error = mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, + VWRITE); + } + + return (error); +} + +static int +mac_bsdextended_check_vnode_revoke(struct ucred *cred, struct vnode *vp, + struct label *label) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VADMIN)); +} + +static int +mac_bsdextended_check_setacl_vnode(struct ucred *cred, struct vnode *vp, + struct label *label, acl_type_t type, struct acl *acl) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VADMIN)); +} + +static int +mac_bsdextended_check_vnode_setextattr(struct ucred *cred, struct vnode *vp, + struct label *label, int attrnamespace, const char *name, struct uio *uio) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VWRITE)); +} + +static int +mac_bsdextended_check_vnode_setflags(struct ucred *cred, struct vnode *vp, + struct label *label, u_long flags) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VADMIN)); +} + +static int +mac_bsdextended_check_vnode_setmode(struct ucred *cred, struct vnode *vp, + struct label *label, mode_t mode) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VADMIN)); +} + +static int +mac_bsdextended_check_vnode_setowner(struct ucred *cred, struct vnode *vp, + struct label *label, uid_t uid, gid_t gid) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VADMIN)); +} + +static int +mac_bsdextended_check_vnode_setutimes(struct ucred *cred, struct vnode *vp, + struct label *label, struct timespec atime, struct timespec utime) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VADMIN)); +} + +static int +mac_bsdextended_check_vnode_stat(struct ucred *cred, struct vnode *vp, + struct label *label) +{ + struct vattr vap; + int error; + + if (!mac_bsdextended_enabled) + return (0); + + error = VOP_GETATTR(vp, &vap, cred, curthread); + if (error) + return (error); + return (mac_bsdextended_check(cred, vap.va_uid, vap.va_gid, VSTAT)); +} + +static struct mac_policy_op_entry mac_bsdextended_ops[] = +{ + { MAC_DESTROY, + (macop_t)mac_bsdextended_destroy }, + { MAC_INIT, + (macop_t)mac_bsdextended_init }, + { MAC_CHECK_VNODE_ACCESS, + (macop_t)mac_bsdextended_check_vnode_access }, + { MAC_CHECK_VNODE_CHDIR, + (macop_t)mac_bsdextended_check_vnode_chdir }, + { MAC_CHECK_VNODE_CHROOT, + (macop_t)mac_bsdextended_check_vnode_chroot }, + { MAC_CHECK_VNODE_CREATE, + (macop_t)mac_bsdextended_check_create_vnode }, + { MAC_CHECK_VNODE_DELETE, + (macop_t)mac_bsdextended_check_vnode_delete }, + { MAC_CHECK_VNODE_DELETEACL, + (macop_t)mac_bsdextended_check_vnode_deleteacl }, + { MAC_CHECK_VNODE_EXEC, + (macop_t)mac_bsdextended_check_vnode_exec }, + { MAC_CHECK_VNODE_GETACL, + (macop_t)mac_bsdextended_check_vnode_getacl }, + { MAC_CHECK_VNODE_GETEXTATTR, + (macop_t)mac_bsdextended_check_vnode_getextattr }, + { MAC_CHECK_VNODE_LOOKUP, + (macop_t)mac_bsdextended_check_vnode_lookup }, + { MAC_CHECK_VNODE_OPEN, + (macop_t)mac_bsdextended_check_vnode_open }, + { MAC_CHECK_VNODE_READDIR, + (macop_t)mac_bsdextended_check_vnode_readdir }, + { MAC_CHECK_VNODE_READLINK, + (macop_t)mac_bsdextended_check_vnode_readdlink }, + { MAC_CHECK_VNODE_RENAME_FROM, + (macop_t)mac_bsdextended_check_vnode_rename_from }, + { MAC_CHECK_VNODE_RENAME_TO, + (macop_t)mac_bsdextended_check_vnode_rename_to }, + { MAC_CHECK_VNODE_REVOKE, + (macop_t)mac_bsdextended_check_vnode_revoke }, + { MAC_CHECK_VNODE_SETACL, + (macop_t)mac_bsdextended_check_setacl_vnode }, + { MAC_CHECK_VNODE_SETEXTATTR, + (macop_t)mac_bsdextended_check_vnode_setextattr }, + { MAC_CHECK_VNODE_SETFLAGS, + (macop_t)mac_bsdextended_check_vnode_setflags }, + { MAC_CHECK_VNODE_SETMODE, + (macop_t)mac_bsdextended_check_vnode_setmode }, + { MAC_CHECK_VNODE_SETOWNER, + (macop_t)mac_bsdextended_check_vnode_setowner }, + { MAC_CHECK_VNODE_SETUTIMES, + (macop_t)mac_bsdextended_check_vnode_setutimes }, + { MAC_CHECK_VNODE_STAT, + (macop_t)mac_bsdextended_check_vnode_stat }, + { MAC_OP_LAST, NULL } +}; + +MAC_POLICY_SET(mac_bsdextended_ops, trustedbsd_mac_bsdextended, + "TrustedBSD MAC/BSD Extended", MPC_LOADTIME_FLAG_UNLOADOK, NULL); |