mirror of
https://gitlab.com/apparmor/apparmor.git
synced 2025-03-04 16:35:02 +01:00
938 lines
27 KiB
Diff
938 lines
27 KiB
Diff
From 4429c3f9522b608300cfe1ae148dc6cdadf3d76c Mon Sep 17 00:00:00 2001
|
|
From: John Johansen <john.johansen@canonical.com>
|
|
Date: Wed, 16 May 2012 10:58:05 -0700
|
|
Subject: [PATCH 3/3] UBUNTU: SAUCE: apparmor: Add the ability to mediate mount
|
|
|
|
Add the ability for apparmor to do mediation of mount operations. Mount
|
|
rules require an updated apparmor_parser (2.8 series) for policy compilation.
|
|
|
|
The basic form of the rules are.
|
|
|
|
[audit] [deny] mount [conds]* [device] [ -> [conds] path],
|
|
[audit] [deny] remount [conds]* [path],
|
|
[audit] [deny] umount [conds]* [path],
|
|
[audit] [deny] pivotroot [oldroot=<value>] <path>
|
|
|
|
remount is just a short cut for mount options=remount
|
|
|
|
where [conds] can be
|
|
fstype=<expr>
|
|
options=<expr>
|
|
|
|
Example mount commands
|
|
mount, # allow all mounts, but not umount or pivotroot
|
|
|
|
mount fstype=procfs, # allow mounting procfs anywhere
|
|
|
|
mount options=(bind, ro) /foo -> /bar, # readonly bind mount
|
|
|
|
mount /dev/sda -> /mnt,
|
|
|
|
mount /dev/sd** -> /mnt/**,
|
|
|
|
mount fstype=overlayfs options=(rw,upperdir=/tmp/upper/,lowerdir=/) -> /mnt/
|
|
|
|
umount,
|
|
|
|
umount /m*,
|
|
|
|
See the apparmor userspace for full documentation
|
|
|
|
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
Acked-by: Kees Cook <kees@ubuntu.com>
|
|
---
|
|
security/apparmor/Makefile | 2 +-
|
|
security/apparmor/apparmorfs.c | 13 +
|
|
security/apparmor/domain.c | 2 +-
|
|
security/apparmor/include/apparmor.h | 3 +-
|
|
security/apparmor/include/audit.h | 11 +
|
|
security/apparmor/include/domain.h | 2 +
|
|
security/apparmor/include/mount.h | 54 +++
|
|
security/apparmor/lsm.c | 60 ++++
|
|
security/apparmor/mount.c | 616 +++++++++++++++++++++++++++++++++++
|
|
9 files changed, 760 insertions(+), 3 deletions(-)
|
|
create mode 100644 security/apparmor/include/mount.h
|
|
create mode 100644 security/apparmor/mount.c
|
|
|
|
diff --git a/security/apparmor/Makefile b/security/apparmor/Makefile
|
|
index a7dc10be232d..01368441f230 100644
|
|
--- a/security/apparmor/Makefile
|
|
+++ b/security/apparmor/Makefile
|
|
@@ -4,7 +4,7 @@ obj-$(CONFIG_SECURITY_APPARMOR) += apparmor.o
|
|
|
|
apparmor-y := apparmorfs.o audit.o capability.o context.o ipc.o lib.o match.o \
|
|
path.o domain.o policy.o policy_unpack.o procattr.o lsm.o \
|
|
- resource.o secid.o file.o policy_ns.o net.o
|
|
+ resource.o secid.o file.o policy_ns.o net.o mount.o
|
|
apparmor-$(CONFIG_SECURITY_APPARMOR_HASH) += crypto.o
|
|
|
|
clean-files := capability_names.h rlim_names.h net_names.h
|
|
diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c
|
|
index 4d236736cfb8..2e8d09e2368b 100644
|
|
--- a/security/apparmor/apparmorfs.c
|
|
+++ b/security/apparmor/apparmorfs.c
|
|
@@ -1205,11 +1205,24 @@ static struct aa_fs_entry aa_fs_entry_policy[] = {
|
|
{ }
|
|
};
|
|
|
|
+static struct aa_fs_entry aa_fs_entry_mount[] = {
|
|
+ AA_FS_FILE_STRING("mask", "mount umount"),
|
|
+ { }
|
|
+};
|
|
+
|
|
+static struct aa_fs_entry aa_fs_entry_namespaces[] = {
|
|
+ AA_FS_FILE_BOOLEAN("profile", 1),
|
|
+ AA_FS_FILE_BOOLEAN("pivot_root", 1),
|
|
+ { }
|
|
+};
|
|
+
|
|
static struct aa_fs_entry aa_fs_entry_features[] = {
|
|
AA_FS_DIR("policy", aa_fs_entry_policy),
|
|
AA_FS_DIR("domain", aa_fs_entry_domain),
|
|
AA_FS_DIR("file", aa_fs_entry_file),
|
|
AA_FS_DIR("network", aa_fs_entry_network),
|
|
+ AA_FS_DIR("mount", aa_fs_entry_mount),
|
|
+ AA_FS_DIR("namespaces", aa_fs_entry_namespaces),
|
|
AA_FS_FILE_U64("capability", VFS_CAP_FLAGS_MASK),
|
|
AA_FS_DIR("rlimit", aa_fs_entry_rlimit),
|
|
AA_FS_DIR("caps", aa_fs_entry_caps),
|
|
diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c
|
|
index 001e133a3c8c..708b7e22b9b5 100644
|
|
--- a/security/apparmor/domain.c
|
|
+++ b/security/apparmor/domain.c
|
|
@@ -237,7 +237,7 @@ static const char *next_name(int xtype, const char *name)
|
|
*
|
|
* Returns: refcounted profile, or NULL on failure (MAYBE NULL)
|
|
*/
|
|
-static struct aa_profile *x_table_lookup(struct aa_profile *profile, u32 xindex)
|
|
+struct aa_profile *x_table_lookup(struct aa_profile *profile, u32 xindex)
|
|
{
|
|
struct aa_profile *new_profile = NULL;
|
|
struct aa_ns *ns = profile->ns;
|
|
diff --git a/security/apparmor/include/apparmor.h b/security/apparmor/include/apparmor.h
|
|
index 1750cc0721c1..3383dc66f30f 100644
|
|
--- a/security/apparmor/include/apparmor.h
|
|
+++ b/security/apparmor/include/apparmor.h
|
|
@@ -27,8 +27,9 @@
|
|
#define AA_CLASS_NET 4
|
|
#define AA_CLASS_RLIMITS 5
|
|
#define AA_CLASS_DOMAIN 6
|
|
+#define AA_CLASS_MOUNT 7
|
|
|
|
-#define AA_CLASS_LAST AA_CLASS_DOMAIN
|
|
+#define AA_CLASS_LAST AA_CLASS_MOUNT
|
|
|
|
/* Control parameters settable through module/boot flags */
|
|
extern enum audit_mode aa_g_audit;
|
|
diff --git a/security/apparmor/include/audit.h b/security/apparmor/include/audit.h
|
|
index 0df708e8748b..41374ad89547 100644
|
|
--- a/security/apparmor/include/audit.h
|
|
+++ b/security/apparmor/include/audit.h
|
|
@@ -70,6 +70,10 @@ enum audit_type {
|
|
#define OP_FMMAP "file_mmap"
|
|
#define OP_FMPROT "file_mprotect"
|
|
|
|
+#define OP_PIVOTROOT "pivotroot"
|
|
+#define OP_MOUNT "mount"
|
|
+#define OP_UMOUNT "umount"
|
|
+
|
|
#define OP_CREATE "create"
|
|
#define OP_POST_CREATE "post_create"
|
|
#define OP_BIND "bind"
|
|
@@ -127,6 +131,13 @@ struct apparmor_audit_data {
|
|
int rlim;
|
|
unsigned long max;
|
|
} rlim;
|
|
+ struct {
|
|
+ const char *src_name;
|
|
+ const char *type;
|
|
+ const char *trans;
|
|
+ const char *data;
|
|
+ unsigned long flags;
|
|
+ } mnt;
|
|
struct {
|
|
int type, protocol;
|
|
struct sock *sk;
|
|
diff --git a/security/apparmor/include/domain.h b/security/apparmor/include/domain.h
|
|
index 30544729878a..7bd21d20a2bd 100644
|
|
--- a/security/apparmor/include/domain.h
|
|
+++ b/security/apparmor/include/domain.h
|
|
@@ -23,6 +23,8 @@ struct aa_domain {
|
|
char **table;
|
|
};
|
|
|
|
+struct aa_profile *x_table_lookup(struct aa_profile *profile, u32 xindex);
|
|
+
|
|
int apparmor_bprm_set_creds(struct linux_binprm *bprm);
|
|
int apparmor_bprm_secureexec(struct linux_binprm *bprm);
|
|
void apparmor_bprm_committing_creds(struct linux_binprm *bprm);
|
|
diff --git a/security/apparmor/include/mount.h b/security/apparmor/include/mount.h
|
|
new file mode 100644
|
|
index 000000000000..a43b1d62e428
|
|
--- /dev/null
|
|
+++ b/security/apparmor/include/mount.h
|
|
@@ -0,0 +1,54 @@
|
|
+/*
|
|
+ * AppArmor security module
|
|
+ *
|
|
+ * This file contains AppArmor file mediation function definitions.
|
|
+ *
|
|
+ * Copyright 2012 Canonical Ltd.
|
|
+ *
|
|
+ * This program is free software; you can redistribute it and/or
|
|
+ * modify it under the terms of the GNU General Public License as
|
|
+ * published by the Free Software Foundation, version 2 of the
|
|
+ * License.
|
|
+ */
|
|
+
|
|
+#ifndef __AA_MOUNT_H
|
|
+#define __AA_MOUNT_H
|
|
+
|
|
+#include <linux/fs.h>
|
|
+#include <linux/path.h>
|
|
+
|
|
+#include "domain.h"
|
|
+#include "policy.h"
|
|
+
|
|
+/* mount perms */
|
|
+#define AA_MAY_PIVOTROOT 0x01
|
|
+#define AA_MAY_MOUNT 0x02
|
|
+#define AA_MAY_UMOUNT 0x04
|
|
+#define AA_AUDIT_DATA 0x40
|
|
+#define AA_CONT_MATCH 0x40
|
|
+
|
|
+#define AA_MS_IGNORE_MASK (MS_KERNMOUNT | MS_NOSEC | MS_ACTIVE | MS_BORN)
|
|
+
|
|
+int aa_remount(struct aa_profile *profile, const struct path *path,
|
|
+ unsigned long flags, void *data);
|
|
+
|
|
+int aa_bind_mount(struct aa_profile *profile, const struct path *path,
|
|
+ const char *old_name, unsigned long flags);
|
|
+
|
|
+
|
|
+int aa_mount_change_type(struct aa_profile *profile, const struct path *path,
|
|
+ unsigned long flags);
|
|
+
|
|
+int aa_move_mount(struct aa_profile *profile, const struct path *path,
|
|
+ const char *old_name);
|
|
+
|
|
+int aa_new_mount(struct aa_profile *profile, const char *dev_name,
|
|
+ const struct path *path, const char *type, unsigned long flags,
|
|
+ void *data);
|
|
+
|
|
+int aa_umount(struct aa_profile *profile, struct vfsmount *mnt, int flags);
|
|
+
|
|
+int aa_pivotroot(struct aa_profile *profile, const struct path *old_path,
|
|
+ const struct path *new_path);
|
|
+
|
|
+#endif /* __AA_MOUNT_H */
|
|
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
|
|
index e3017129a404..ee58a2cca74f 100644
|
|
--- a/security/apparmor/lsm.c
|
|
+++ b/security/apparmor/lsm.c
|
|
@@ -38,6 +38,7 @@
|
|
#include "include/policy.h"
|
|
#include "include/policy_ns.h"
|
|
#include "include/procattr.h"
|
|
+#include "include/mount.h"
|
|
|
|
/* Flag indicating whether initialization completed */
|
|
int apparmor_initialized __initdata;
|
|
@@ -479,6 +480,61 @@ static int apparmor_file_mprotect(struct vm_area_struct *vma,
|
|
!(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
|
|
}
|
|
|
|
+static int apparmor_sb_mount(const char *dev_name, const struct path *path,
|
|
+ const char *type, unsigned long flags, void *data)
|
|
+{
|
|
+ struct aa_profile *profile;
|
|
+ int error = 0;
|
|
+
|
|
+ /* Discard magic */
|
|
+ if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
|
|
+ flags &= ~MS_MGC_MSK;
|
|
+
|
|
+ flags &= ~AA_MS_IGNORE_MASK;
|
|
+
|
|
+ profile = __aa_current_profile();
|
|
+ if (!unconfined(profile)) {
|
|
+ if (flags & MS_REMOUNT)
|
|
+ error = aa_remount(profile, path, flags, data);
|
|
+ else if (flags & MS_BIND)
|
|
+ error = aa_bind_mount(profile, path, dev_name, flags);
|
|
+ else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
|
|
+ MS_UNBINDABLE))
|
|
+ error = aa_mount_change_type(profile, path, flags);
|
|
+ else if (flags & MS_MOVE)
|
|
+ error = aa_move_mount(profile, path, dev_name);
|
|
+ else
|
|
+ error = aa_new_mount(profile, dev_name, path, type,
|
|
+ flags, data);
|
|
+ }
|
|
+ return error;
|
|
+}
|
|
+
|
|
+static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
|
|
+{
|
|
+ struct aa_profile *profile;
|
|
+ int error = 0;
|
|
+
|
|
+ profile = __aa_current_profile();
|
|
+ if (!unconfined(profile))
|
|
+ error = aa_umount(profile, mnt, flags);
|
|
+
|
|
+ return error;
|
|
+}
|
|
+
|
|
+static int apparmor_sb_pivotroot(const struct path *old_path,
|
|
+ const struct path *new_path)
|
|
+{
|
|
+ struct aa_profile *profile;
|
|
+ int error = 0;
|
|
+
|
|
+ profile = __aa_current_profile();
|
|
+ if (!unconfined(profile))
|
|
+ error = aa_pivotroot(profile, old_path, new_path);
|
|
+
|
|
+ return error;
|
|
+}
|
|
+
|
|
static int apparmor_getprocattr(struct task_struct *task, char *name,
|
|
char **value)
|
|
{
|
|
@@ -692,6 +748,10 @@ static struct security_hook_list apparmor_hooks[] = {
|
|
LSM_HOOK_INIT(capget, apparmor_capget),
|
|
LSM_HOOK_INIT(capable, apparmor_capable),
|
|
|
|
+ LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
|
|
+ LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
|
|
+ LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),
|
|
+
|
|
LSM_HOOK_INIT(path_link, apparmor_path_link),
|
|
LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
|
|
LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
|
|
diff --git a/security/apparmor/mount.c b/security/apparmor/mount.c
|
|
new file mode 100644
|
|
index 000000000000..9e95a41c015c
|
|
--- /dev/null
|
|
+++ b/security/apparmor/mount.c
|
|
@@ -0,0 +1,616 @@
|
|
+/*
|
|
+ * AppArmor security module
|
|
+ *
|
|
+ * This file contains AppArmor mediation of files
|
|
+ *
|
|
+ * Copyright (C) 1998-2008 Novell/SUSE
|
|
+ * Copyright 2009-2012 Canonical Ltd.
|
|
+ *
|
|
+ * This program is free software; you can redistribute it and/or
|
|
+ * modify it under the terms of the GNU General Public License as
|
|
+ * published by the Free Software Foundation, version 2 of the
|
|
+ * License.
|
|
+ */
|
|
+
|
|
+#include <linux/fs.h>
|
|
+#include <linux/mount.h>
|
|
+#include <linux/namei.h>
|
|
+
|
|
+#include "include/apparmor.h"
|
|
+#include "include/audit.h"
|
|
+#include "include/context.h"
|
|
+#include "include/domain.h"
|
|
+#include "include/file.h"
|
|
+#include "include/match.h"
|
|
+#include "include/mount.h"
|
|
+#include "include/path.h"
|
|
+#include "include/policy.h"
|
|
+
|
|
+
|
|
+static void audit_mnt_flags(struct audit_buffer *ab, unsigned long flags)
|
|
+{
|
|
+ if (flags & MS_RDONLY)
|
|
+ audit_log_format(ab, "ro");
|
|
+ else
|
|
+ audit_log_format(ab, "rw");
|
|
+ if (flags & MS_NOSUID)
|
|
+ audit_log_format(ab, ", nosuid");
|
|
+ if (flags & MS_NODEV)
|
|
+ audit_log_format(ab, ", nodev");
|
|
+ if (flags & MS_NOEXEC)
|
|
+ audit_log_format(ab, ", noexec");
|
|
+ if (flags & MS_SYNCHRONOUS)
|
|
+ audit_log_format(ab, ", sync");
|
|
+ if (flags & MS_REMOUNT)
|
|
+ audit_log_format(ab, ", remount");
|
|
+ if (flags & MS_MANDLOCK)
|
|
+ audit_log_format(ab, ", mand");
|
|
+ if (flags & MS_DIRSYNC)
|
|
+ audit_log_format(ab, ", dirsync");
|
|
+ if (flags & MS_NOATIME)
|
|
+ audit_log_format(ab, ", noatime");
|
|
+ if (flags & MS_NODIRATIME)
|
|
+ audit_log_format(ab, ", nodiratime");
|
|
+ if (flags & MS_BIND)
|
|
+ audit_log_format(ab, flags & MS_REC ? ", rbind" : ", bind");
|
|
+ if (flags & MS_MOVE)
|
|
+ audit_log_format(ab, ", move");
|
|
+ if (flags & MS_SILENT)
|
|
+ audit_log_format(ab, ", silent");
|
|
+ if (flags & MS_POSIXACL)
|
|
+ audit_log_format(ab, ", acl");
|
|
+ if (flags & MS_UNBINDABLE)
|
|
+ audit_log_format(ab, flags & MS_REC ? ", runbindable" :
|
|
+ ", unbindable");
|
|
+ if (flags & MS_PRIVATE)
|
|
+ audit_log_format(ab, flags & MS_REC ? ", rprivate" :
|
|
+ ", private");
|
|
+ if (flags & MS_SLAVE)
|
|
+ audit_log_format(ab, flags & MS_REC ? ", rslave" :
|
|
+ ", slave");
|
|
+ if (flags & MS_SHARED)
|
|
+ audit_log_format(ab, flags & MS_REC ? ", rshared" :
|
|
+ ", shared");
|
|
+ if (flags & MS_RELATIME)
|
|
+ audit_log_format(ab, ", relatime");
|
|
+ if (flags & MS_I_VERSION)
|
|
+ audit_log_format(ab, ", iversion");
|
|
+ if (flags & MS_STRICTATIME)
|
|
+ audit_log_format(ab, ", strictatime");
|
|
+ if (flags & MS_NOUSER)
|
|
+ audit_log_format(ab, ", nouser");
|
|
+}
|
|
+
|
|
+/**
|
|
+ * audit_cb - call back for mount specific audit fields
|
|
+ * @ab: audit_buffer (NOT NULL)
|
|
+ * @va: audit struct to audit values of (NOT NULL)
|
|
+ */
|
|
+static void audit_cb(struct audit_buffer *ab, void *va)
|
|
+{
|
|
+ struct common_audit_data *sa = va;
|
|
+
|
|
+ if (aad(sa)->mnt.type) {
|
|
+ audit_log_format(ab, " fstype=");
|
|
+ audit_log_untrustedstring(ab, aad(sa)->mnt.type);
|
|
+ }
|
|
+ if (aad(sa)->mnt.src_name) {
|
|
+ audit_log_format(ab, " srcname=");
|
|
+ audit_log_untrustedstring(ab, aad(sa)->mnt.src_name);
|
|
+ }
|
|
+ if (aad(sa)->mnt.trans) {
|
|
+ audit_log_format(ab, " trans=");
|
|
+ audit_log_untrustedstring(ab, aad(sa)->mnt.trans);
|
|
+ }
|
|
+ if (aad(sa)->mnt.flags) {
|
|
+ audit_log_format(ab, " flags=\"");
|
|
+ audit_mnt_flags(ab, aad(sa)->mnt.flags);
|
|
+ audit_log_format(ab, "\"");
|
|
+ }
|
|
+ if (aad(sa)->mnt.data) {
|
|
+ audit_log_format(ab, " options=");
|
|
+ audit_log_untrustedstring(ab, aad(sa)->mnt.data);
|
|
+ }
|
|
+}
|
|
+
|
|
+/**
|
|
+ * audit_mount - handle the auditing of mount operations
|
|
+ * @profile: the profile being enforced (NOT NULL)
|
|
+ * @gfp: allocation flags
|
|
+ * @op: operation being mediated (NOT NULL)
|
|
+ * @name: name of object being mediated (MAYBE NULL)
|
|
+ * @src_name: src_name of object being mediated (MAYBE_NULL)
|
|
+ * @type: type of filesystem (MAYBE_NULL)
|
|
+ * @trans: name of trans (MAYBE NULL)
|
|
+ * @flags: filesystem idependent mount flags
|
|
+ * @data: filesystem mount flags
|
|
+ * @request: permissions requested
|
|
+ * @perms: the permissions computed for the request (NOT NULL)
|
|
+ * @info: extra information message (MAYBE NULL)
|
|
+ * @error: 0 if operation allowed else failure error code
|
|
+ *
|
|
+ * Returns: %0 or error on failure
|
|
+ */
|
|
+static int audit_mount(struct aa_profile *profile, gfp_t gfp, const char *op,
|
|
+ const char *name, const char *src_name,
|
|
+ const char *type, const char *trans,
|
|
+ unsigned long flags, const void *data, u32 request,
|
|
+ struct file_perms *perms, const char *info, int error)
|
|
+{
|
|
+ int audit_type = AUDIT_APPARMOR_AUTO;
|
|
+ DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, op);
|
|
+
|
|
+ if (likely(!error)) {
|
|
+ u32 mask = perms->audit;
|
|
+
|
|
+ if (unlikely(AUDIT_MODE(profile) == AUDIT_ALL))
|
|
+ mask = 0xffff;
|
|
+
|
|
+ /* mask off perms that are not being force audited */
|
|
+ request &= mask;
|
|
+
|
|
+ if (likely(!request))
|
|
+ return 0;
|
|
+ audit_type = AUDIT_APPARMOR_AUDIT;
|
|
+ } else {
|
|
+ /* only report permissions that were denied */
|
|
+ request = request & ~perms->allow;
|
|
+
|
|
+ if (request & perms->kill)
|
|
+ audit_type = AUDIT_APPARMOR_KILL;
|
|
+
|
|
+ /* quiet known rejects, assumes quiet and kill do not overlap */
|
|
+ if ((request & perms->quiet) &&
|
|
+ AUDIT_MODE(profile) != AUDIT_NOQUIET &&
|
|
+ AUDIT_MODE(profile) != AUDIT_ALL)
|
|
+ request &= ~perms->quiet;
|
|
+
|
|
+ if (!request)
|
|
+ return COMPLAIN_MODE(profile) ?
|
|
+ complain_error(error) : error;
|
|
+ }
|
|
+
|
|
+ aad(&sa)->name = name;
|
|
+ aad(&sa)->mnt.src_name = src_name;
|
|
+ aad(&sa)->mnt.type = type;
|
|
+ aad(&sa)->mnt.trans = trans;
|
|
+ aad(&sa)->mnt.flags = flags;
|
|
+ if (data && (perms->audit & AA_AUDIT_DATA))
|
|
+ aad(&sa)->mnt.data = data;
|
|
+ aad(&sa)->info = info;
|
|
+ aad(&sa)->error = error;
|
|
+
|
|
+ return aa_audit(audit_type, profile, &sa, audit_cb);
|
|
+}
|
|
+
|
|
+/**
|
|
+ * match_mnt_flags - Do an ordered match on mount flags
|
|
+ * @dfa: dfa to match against
|
|
+ * @state: state to start in
|
|
+ * @flags: mount flags to match against
|
|
+ *
|
|
+ * Mount flags are encoded as an ordered match. This is done instead of
|
|
+ * checking against a simple bitmask, to allow for logical operations
|
|
+ * on the flags.
|
|
+ *
|
|
+ * Returns: next state after flags match
|
|
+ */
|
|
+static unsigned int match_mnt_flags(struct aa_dfa *dfa, unsigned int state,
|
|
+ unsigned long flags)
|
|
+{
|
|
+ unsigned int i;
|
|
+
|
|
+ for (i = 0; i <= 31 ; ++i) {
|
|
+ if ((1 << i) & flags)
|
|
+ state = aa_dfa_next(dfa, state, i + 1);
|
|
+ }
|
|
+
|
|
+ return state;
|
|
+}
|
|
+
|
|
+/**
|
|
+ * compute_mnt_perms - compute mount permission associated with @state
|
|
+ * @dfa: dfa to match against (NOT NULL)
|
|
+ * @state: state match finished in
|
|
+ *
|
|
+ * Returns: mount permissions
|
|
+ */
|
|
+static struct file_perms compute_mnt_perms(struct aa_dfa *dfa,
|
|
+ unsigned int state)
|
|
+{
|
|
+ struct file_perms perms;
|
|
+
|
|
+ perms.kill = 0;
|
|
+ perms.allow = dfa_user_allow(dfa, state);
|
|
+ perms.audit = dfa_user_audit(dfa, state);
|
|
+ perms.quiet = dfa_user_quiet(dfa, state);
|
|
+ perms.xindex = dfa_user_xindex(dfa, state);
|
|
+
|
|
+ return perms;
|
|
+}
|
|
+
|
|
+static const char *mnt_info_table[] = {
|
|
+ "match succeeded",
|
|
+ "failed mntpnt match",
|
|
+ "failed srcname match",
|
|
+ "failed type match",
|
|
+ "failed flags match",
|
|
+ "failed data match"
|
|
+};
|
|
+
|
|
+/*
|
|
+ * Returns 0 on success else element that match failed in, this is the
|
|
+ * index into the mnt_info_table above
|
|
+ */
|
|
+static int do_match_mnt(struct aa_dfa *dfa, unsigned int start,
|
|
+ const char *mntpnt, const char *devname,
|
|
+ const char *type, unsigned long flags,
|
|
+ void *data, bool binary, struct file_perms *perms)
|
|
+{
|
|
+ unsigned int state;
|
|
+
|
|
+ state = aa_dfa_match(dfa, start, mntpnt);
|
|
+ state = aa_dfa_null_transition(dfa, state);
|
|
+ if (!state)
|
|
+ return 1;
|
|
+
|
|
+ if (devname)
|
|
+ state = aa_dfa_match(dfa, state, devname);
|
|
+ state = aa_dfa_null_transition(dfa, state);
|
|
+ if (!state)
|
|
+ return 2;
|
|
+
|
|
+ if (type)
|
|
+ state = aa_dfa_match(dfa, state, type);
|
|
+ state = aa_dfa_null_transition(dfa, state);
|
|
+ if (!state)
|
|
+ return 3;
|
|
+
|
|
+ state = match_mnt_flags(dfa, state, flags);
|
|
+ if (!state)
|
|
+ return 4;
|
|
+ *perms = compute_mnt_perms(dfa, state);
|
|
+ if (perms->allow & AA_MAY_MOUNT)
|
|
+ return 0;
|
|
+
|
|
+ /* only match data if not binary and the DFA flags data is expected */
|
|
+ if (data && !binary && (perms->allow & AA_CONT_MATCH)) {
|
|
+ state = aa_dfa_null_transition(dfa, state);
|
|
+ if (!state)
|
|
+ return 4;
|
|
+
|
|
+ state = aa_dfa_match(dfa, state, data);
|
|
+ if (!state)
|
|
+ return 5;
|
|
+ *perms = compute_mnt_perms(dfa, state);
|
|
+ if (perms->allow & AA_MAY_MOUNT)
|
|
+ return 0;
|
|
+ }
|
|
+
|
|
+ /* failed at end of flags match */
|
|
+ return 4;
|
|
+}
|
|
+
|
|
+/**
|
|
+ * match_mnt - handle path matching for mount
|
|
+ * @profile: the confining profile
|
|
+ * @mntpnt: string for the mntpnt (NOT NULL)
|
|
+ * @devname: string for the devname/src_name (MAYBE NULL)
|
|
+ * @type: string for the dev type (MAYBE NULL)
|
|
+ * @flags: mount flags to match
|
|
+ * @data: fs mount data (MAYBE NULL)
|
|
+ * @binary: whether @data is binary
|
|
+ * @perms: Returns: permission found by the match
|
|
+ * @info: Returns: infomation string about the match for logging
|
|
+ *
|
|
+ * Returns: 0 on success else error
|
|
+ */
|
|
+static int match_mnt(struct aa_profile *profile, const char *mntpnt,
|
|
+ const char *devname, const char *type,
|
|
+ unsigned long flags, void *data, bool binary,
|
|
+ struct file_perms *perms, const char **info)
|
|
+{
|
|
+ int pos;
|
|
+
|
|
+ if (!profile->policy.dfa)
|
|
+ return -EACCES;
|
|
+
|
|
+ pos = do_match_mnt(profile->policy.dfa,
|
|
+ profile->policy.start[AA_CLASS_MOUNT],
|
|
+ mntpnt, devname, type, flags, data, binary, perms);
|
|
+ if (pos) {
|
|
+ *info = mnt_info_table[pos];
|
|
+ return -EACCES;
|
|
+ }
|
|
+
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+static int path_flags(struct aa_profile *profile, const struct path *path)
|
|
+{
|
|
+ return profile->path_flags |
|
|
+ S_ISDIR(path->dentry->d_inode->i_mode) ? PATH_IS_DIR : 0;
|
|
+}
|
|
+
|
|
+int aa_remount(struct aa_profile *profile, const struct path *path,
|
|
+ unsigned long flags, void *data)
|
|
+{
|
|
+ struct file_perms perms = { };
|
|
+ const char *name, *info = NULL;
|
|
+ char *buffer = NULL;
|
|
+ int binary, error;
|
|
+
|
|
+ binary = path->dentry->d_sb->s_type->fs_flags & FS_BINARY_MOUNTDATA;
|
|
+
|
|
+ error = aa_path_name(path, path_flags(profile, path), &buffer, &name,
|
|
+ &info);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+
|
|
+ error = match_mnt(profile, name, NULL, NULL, flags, data, binary,
|
|
+ &perms, &info);
|
|
+
|
|
+audit:
|
|
+ error = audit_mount(profile, GFP_KERNEL, OP_MOUNT, name, NULL, NULL,
|
|
+ NULL, flags, data, AA_MAY_MOUNT, &perms, info,
|
|
+ error);
|
|
+ kfree(buffer);
|
|
+
|
|
+ return error;
|
|
+}
|
|
+
|
|
+int aa_bind_mount(struct aa_profile *profile, const struct path *path,
|
|
+ const char *dev_name, unsigned long flags)
|
|
+{
|
|
+ struct file_perms perms = { };
|
|
+ char *buffer = NULL, *old_buffer = NULL;
|
|
+ const char *name, *old_name = NULL, *info = NULL;
|
|
+ struct path old_path;
|
|
+ int error;
|
|
+
|
|
+ if (!dev_name || !*dev_name)
|
|
+ return -EINVAL;
|
|
+
|
|
+ flags &= MS_REC | MS_BIND;
|
|
+
|
|
+ error = aa_path_name(path, path_flags(profile, path), &buffer, &name,
|
|
+ &info);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+
|
|
+ error = kern_path(dev_name, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &old_path);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+
|
|
+ error = aa_path_name(&old_path, path_flags(profile, &old_path),
|
|
+ &old_buffer, &old_name, &info);
|
|
+ path_put(&old_path);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+
|
|
+ error = match_mnt(profile, name, old_name, NULL, flags, NULL, 0,
|
|
+ &perms, &info);
|
|
+
|
|
+audit:
|
|
+ error = audit_mount(profile, GFP_KERNEL, OP_MOUNT, name, old_name,
|
|
+ NULL, NULL, flags, NULL, AA_MAY_MOUNT, &perms,
|
|
+ info, error);
|
|
+ kfree(buffer);
|
|
+ kfree(old_buffer);
|
|
+
|
|
+ return error;
|
|
+}
|
|
+
|
|
+int aa_mount_change_type(struct aa_profile *profile, const struct path *path,
|
|
+ unsigned long flags)
|
|
+{
|
|
+ struct file_perms perms = { };
|
|
+ char *buffer = NULL;
|
|
+ const char *name, *info = NULL;
|
|
+ int error;
|
|
+
|
|
+ /* These are the flags allowed by do_change_type() */
|
|
+ flags &= (MS_REC | MS_SILENT | MS_SHARED | MS_PRIVATE | MS_SLAVE |
|
|
+ MS_UNBINDABLE);
|
|
+
|
|
+ error = aa_path_name(path, path_flags(profile, path), &buffer, &name,
|
|
+ &info);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+
|
|
+ error = match_mnt(profile, name, NULL, NULL, flags, NULL, 0, &perms,
|
|
+ &info);
|
|
+
|
|
+audit:
|
|
+ error = audit_mount(profile, GFP_KERNEL, OP_MOUNT, name, NULL, NULL,
|
|
+ NULL, flags, NULL, AA_MAY_MOUNT, &perms, info,
|
|
+ error);
|
|
+ kfree(buffer);
|
|
+
|
|
+ return error;
|
|
+}
|
|
+
|
|
+int aa_move_mount(struct aa_profile *profile, const struct path *path,
|
|
+ const char *orig_name)
|
|
+{
|
|
+ struct file_perms perms = { };
|
|
+ char *buffer = NULL, *old_buffer = NULL;
|
|
+ const char *name, *old_name = NULL, *info = NULL;
|
|
+ struct path old_path;
|
|
+ int error;
|
|
+
|
|
+ if (!orig_name || !*orig_name)
|
|
+ return -EINVAL;
|
|
+
|
|
+ error = aa_path_name(path, path_flags(profile, path), &buffer, &name,
|
|
+ &info);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+
|
|
+ error = kern_path(orig_name, LOOKUP_FOLLOW, &old_path);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+
|
|
+ error = aa_path_name(&old_path, path_flags(profile, &old_path),
|
|
+ &old_buffer, &old_name, &info);
|
|
+ path_put(&old_path);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+
|
|
+ error = match_mnt(profile, name, old_name, NULL, MS_MOVE, NULL, 0,
|
|
+ &perms, &info);
|
|
+
|
|
+audit:
|
|
+ error = audit_mount(profile, GFP_KERNEL, OP_MOUNT, name, old_name,
|
|
+ NULL, NULL, MS_MOVE, NULL, AA_MAY_MOUNT, &perms,
|
|
+ info, error);
|
|
+ kfree(buffer);
|
|
+ kfree(old_buffer);
|
|
+
|
|
+ return error;
|
|
+}
|
|
+
|
|
+int aa_new_mount(struct aa_profile *profile, const char *orig_dev_name,
|
|
+ const struct path *path, const char *type, unsigned long flags,
|
|
+ void *data)
|
|
+{
|
|
+ struct file_perms perms = { };
|
|
+ char *buffer = NULL, *dev_buffer = NULL;
|
|
+ const char *name = NULL, *dev_name = NULL, *info = NULL;
|
|
+ int binary = 1;
|
|
+ int error;
|
|
+
|
|
+ dev_name = orig_dev_name;
|
|
+ if (type) {
|
|
+ int requires_dev;
|
|
+ struct file_system_type *fstype = get_fs_type(type);
|
|
+ if (!fstype)
|
|
+ return -ENODEV;
|
|
+
|
|
+ binary = fstype->fs_flags & FS_BINARY_MOUNTDATA;
|
|
+ requires_dev = fstype->fs_flags & FS_REQUIRES_DEV;
|
|
+ put_filesystem(fstype);
|
|
+
|
|
+ if (requires_dev) {
|
|
+ struct path dev_path;
|
|
+
|
|
+ if (!dev_name || !*dev_name) {
|
|
+ error = -ENOENT;
|
|
+ goto out;
|
|
+ }
|
|
+
|
|
+ error = kern_path(dev_name, LOOKUP_FOLLOW, &dev_path);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+
|
|
+ error = aa_path_name(&dev_path,
|
|
+ path_flags(profile, &dev_path),
|
|
+ &dev_buffer, &dev_name, &info);
|
|
+ path_put(&dev_path);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+ }
|
|
+ }
|
|
+
|
|
+ error = aa_path_name(path, path_flags(profile, path), &buffer, &name,
|
|
+ &info);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+
|
|
+ error = match_mnt(profile, name, dev_name, type, flags, data, binary,
|
|
+ &perms, &info);
|
|
+
|
|
+audit:
|
|
+ error = audit_mount(profile, GFP_KERNEL, OP_MOUNT, name, dev_name,
|
|
+ type, NULL, flags, data, AA_MAY_MOUNT, &perms, info,
|
|
+ error);
|
|
+ kfree(buffer);
|
|
+ kfree(dev_buffer);
|
|
+
|
|
+out:
|
|
+ return error;
|
|
+
|
|
+}
|
|
+
|
|
+int aa_umount(struct aa_profile *profile, struct vfsmount *mnt, int flags)
|
|
+{
|
|
+ struct file_perms perms = { };
|
|
+ char *buffer = NULL;
|
|
+ const char *name, *info = NULL;
|
|
+ int error;
|
|
+
|
|
+ struct path path = { mnt, mnt->mnt_root };
|
|
+ error = aa_path_name(&path, path_flags(profile, &path), &buffer, &name,
|
|
+ &info);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+
|
|
+ if (!error && profile->policy.dfa) {
|
|
+ unsigned int state;
|
|
+ state = aa_dfa_match(profile->policy.dfa,
|
|
+ profile->policy.start[AA_CLASS_MOUNT],
|
|
+ name);
|
|
+ perms = compute_mnt_perms(profile->policy.dfa, state);
|
|
+ }
|
|
+
|
|
+ if (AA_MAY_UMOUNT & ~perms.allow)
|
|
+ error = -EACCES;
|
|
+
|
|
+audit:
|
|
+ error = audit_mount(profile, GFP_KERNEL, OP_UMOUNT, name, NULL, NULL,
|
|
+ NULL, 0, NULL, AA_MAY_UMOUNT, &perms, info, error);
|
|
+ kfree(buffer);
|
|
+
|
|
+ return error;
|
|
+}
|
|
+
|
|
+int aa_pivotroot(struct aa_profile *profile, const struct path *old_path,
|
|
+ const struct path *new_path)
|
|
+{
|
|
+ struct file_perms perms = { };
|
|
+ struct aa_profile *target = NULL;
|
|
+ char *old_buffer = NULL, *new_buffer = NULL;
|
|
+ const char *old_name, *new_name = NULL, *info = NULL;
|
|
+ int error;
|
|
+
|
|
+ error = aa_path_name(old_path, path_flags(profile, old_path),
|
|
+ &old_buffer, &old_name, &info);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+
|
|
+ error = aa_path_name(new_path, path_flags(profile, new_path),
|
|
+ &new_buffer, &new_name, &info);
|
|
+ if (error)
|
|
+ goto audit;
|
|
+
|
|
+ if (profile->policy.dfa) {
|
|
+ unsigned int state;
|
|
+ state = aa_dfa_match(profile->policy.dfa,
|
|
+ profile->policy.start[AA_CLASS_MOUNT],
|
|
+ new_name);
|
|
+ state = aa_dfa_null_transition(profile->policy.dfa, state);
|
|
+ state = aa_dfa_match(profile->policy.dfa, state, old_name);
|
|
+ perms = compute_mnt_perms(profile->policy.dfa, state);
|
|
+ }
|
|
+
|
|
+ if (AA_MAY_PIVOTROOT & perms.allow) {
|
|
+ if ((perms.xindex & AA_X_TYPE_MASK) == AA_X_TABLE) {
|
|
+ target = x_table_lookup(profile, perms.xindex);
|
|
+ if (!target)
|
|
+ error = -ENOENT;
|
|
+ else
|
|
+ error = aa_replace_current_profile(target);
|
|
+ }
|
|
+ } else
|
|
+ error = -EACCES;
|
|
+
|
|
+audit:
|
|
+ error = audit_mount(profile, GFP_KERNEL, OP_PIVOTROOT, new_name,
|
|
+ old_name, NULL, target ? target->base.name : NULL,
|
|
+ 0, NULL, AA_MAY_PIVOTROOT, &perms, info, error);
|
|
+ aa_put_profile(target);
|
|
+ kfree(old_buffer);
|
|
+ kfree(new_buffer);
|
|
+
|
|
+ return error;
|
|
+}
|
|
--
|
|
2.11.0
|
|
|