2 files changed, 674 insertions, 0 deletions

diff --git a/security/apparmor/file.c b/security/apparmor/file.c
new file mode 100644
index 000000000000..7312db741219
--- /dev/null
+++ b/security/apparmor/file.c
@@ -0,0 +1,457 @@
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor mediation of files
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2010 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 "include/apparmor.h"
+#include "include/audit.h"
+#include "include/file.h"
+#include "include/match.h"
+#include "include/path.h"
+#include "include/policy.h"
+
+struct file_perms nullperms;
+
+
+/**
+ * audit_file_mask - convert mask to permission string
+ * @buffer: buffer to write string to (NOT NULL)
+ * @mask: permission mask to convert
+ */
+static void audit_file_mask(struct audit_buffer *ab, u32 mask)
+{
+        char str[10];
+
+        char *m = str;
+
+        if (mask & AA_EXEC_MMAP)
+                *m++ = 'm';
+        if (mask & (MAY_READ | AA_MAY_META_READ))
+                *m++ = 'r';
+        if (mask & (MAY_WRITE | AA_MAY_META_WRITE | AA_MAY_CHMOD |
+                    AA_MAY_CHOWN))
+                *m++ = 'w';
+        else if (mask & MAY_APPEND)
+                *m++ = 'a';
+        if (mask & AA_MAY_CREATE)
+                *m++ = 'c';
+        if (mask & AA_MAY_DELETE)
+                *m++ = 'd';
+        if (mask & AA_MAY_LINK)
+                *m++ = 'l';
+        if (mask & AA_MAY_LOCK)
+                *m++ = 'k';
+        if (mask & MAY_EXEC)
+                *m++ = 'x';
+        *m = '\0';
+
+        audit_log_string(ab, str);
+}
+
+/**
+ * file_audit_cb - call back for file specific audit fields
+ * @ab: audit_buffer  (NOT NULL)
+ * @va: audit struct to audit values of  (NOT NULL)
+ */
+static void file_audit_cb(struct audit_buffer *ab, void *va)
+{
+        struct common_audit_data *sa = va;
+        uid_t fsuid = current_fsuid();
+
+        if (sa->aad.fs.request & AA_AUDIT_FILE_MASK) {
+                audit_log_format(ab, " requested_mask=");
+                audit_file_mask(ab, sa->aad.fs.request);
+        }
+        if (sa->aad.fs.denied & AA_AUDIT_FILE_MASK) {
+                audit_log_format(ab, " denied_mask=");
+                audit_file_mask(ab, sa->aad.fs.denied);
+        }
+        if (sa->aad.fs.request & AA_AUDIT_FILE_MASK) {
+                audit_log_format(ab, " fsuid=%d", fsuid);
+                audit_log_format(ab, " ouid=%d", sa->aad.fs.ouid);
+        }
+
+        if (sa->aad.fs.target) {
+                audit_log_format(ab, " target=");
+                audit_log_untrustedstring(ab, sa->aad.fs.target);
+        }
+}
+
+/**
+ * aa_audit_file - handle the auditing of file operations
+ * @profile: the profile being enforced  (NOT NULL)
+ * @perms: the permissions computed for the request (NOT NULL)
+ * @gfp: allocation flags
+ * @op: operation being mediated
+ * @request: permissions requested
+ * @name: name of object being mediated (MAYBE NULL)
+ * @target: name of target (MAYBE NULL)
+ * @ouid: object uid
+ * @info: extra information message (MAYBE NULL)
+ * @error: 0 if operation allowed else failure error code
+ *
+ * Returns: %0 or error on failure
+ */
+int aa_audit_file(struct aa_profile *profile, struct file_perms *perms,
+                  gfp_t gfp, int op, u32 request, const char *name,
+                  const char *target, uid_t ouid, const char *info, int error)
+{
+        int type = AUDIT_APPARMOR_AUTO;
+        struct common_audit_data sa;
+        COMMON_AUDIT_DATA_INIT(&sa, NONE);
+        sa.aad.op = op,
+        sa.aad.fs.request = request;
+        sa.aad.name = name;
+        sa.aad.fs.target = target;
+        sa.aad.fs.ouid = ouid;
+        sa.aad.info = info;
+        sa.aad.error = error;
+
+        if (likely(!sa.aad.error)) {
+                u32 mask = perms->audit;
+
+                if (unlikely(AUDIT_MODE(profile) == AUDIT_ALL))
+                        mask = 0xffff;
+
+                /* mask off perms that are not being force audited */
+                sa.aad.fs.request &= mask;
+
+                if (likely(!sa.aad.fs.request))
+                        return 0;
+                type = AUDIT_APPARMOR_AUDIT;
+        } else {
+                /* only report permissions that were denied */
+                sa.aad.fs.request = sa.aad.fs.request & ~perms->allow;
+
+                if (sa.aad.fs.request & perms->kill)
+                        type = AUDIT_APPARMOR_KILL;
+
+                /* quiet known rejects, assumes quiet and kill do not overlap */
+                if ((sa.aad.fs.request & perms->quiet) &&
+                    AUDIT_MODE(profile) != AUDIT_NOQUIET &&
+                    AUDIT_MODE(profile) != AUDIT_ALL)
+                        sa.aad.fs.request &= ~perms->quiet;
+
+                if (!sa.aad.fs.request)
+                        return COMPLAIN_MODE(profile) ? 0 : sa.aad.error;
+        }
+
+        sa.aad.fs.denied = sa.aad.fs.request & ~perms->allow;
+        return aa_audit(type, profile, gfp, &sa, file_audit_cb);
+}
+
+/**
+ * map_old_perms - map old file perms layout to the new layout
+ * @old: permission set in old mapping
+ *
+ * Returns: new permission mapping
+ */
+static u32 map_old_perms(u32 old)
+{
+        u32 new = old & 0xf;
+        if (old & MAY_READ)
+                new |= AA_MAY_META_READ;
+        if (old & MAY_WRITE)
+                new |= AA_MAY_META_WRITE | AA_MAY_CREATE | AA_MAY_DELETE |
+                        AA_MAY_CHMOD | AA_MAY_CHOWN;
+        if (old & 0x10)
+                new |= AA_MAY_LINK;
+        /* the old mapping lock and link_subset flags where overlaid
+         * and use was determined by part of a pair that they were in
+         */
+        if (old & 0x20)
+                new |= AA_MAY_LOCK | AA_LINK_SUBSET;
+        if (old & 0x40) /* AA_EXEC_MMAP */
+                new |= AA_EXEC_MMAP;
+
+        new |= AA_MAY_META_READ;
+
+        return new;
+}
+
+/**
+ * compute_perms - convert dfa compressed perms to internal perms
+ * @dfa: dfa to compute perms for   (NOT NULL)
+ * @state: state in dfa
+ * @cond:  conditions to consider  (NOT NULL)
+ *
+ * TODO: convert from dfa + state to permission entry, do computation conversion
+ *       at load time.
+ *
+ * Returns: computed permission set
+ */
+static struct file_perms compute_perms(struct aa_dfa *dfa, unsigned int state,
+                                       struct path_cond *cond)
+{
+        struct file_perms perms;
+
+        /* FIXME: change over to new dfa format
+         * currently file perms are encoded in the dfa, new format
+         * splits the permissions from the dfa.  This mapping can be
+         * done at profile load
+         */
+        perms.kill = 0;
+
+        if (current_fsuid() == cond->uid) {
+                perms.allow = map_old_perms(dfa_user_allow(dfa, state));
+                perms.audit = map_old_perms(dfa_user_audit(dfa, state));
+                perms.quiet = map_old_perms(dfa_user_quiet(dfa, state));
+                perms.xindex = dfa_user_xindex(dfa, state);
+        } else {
+                perms.allow = map_old_perms(dfa_other_allow(dfa, state));
+                perms.audit = map_old_perms(dfa_other_audit(dfa, state));
+                perms.quiet = map_old_perms(dfa_other_quiet(dfa, state));
+                perms.xindex = dfa_other_xindex(dfa, state);
+        }
+
+        /* change_profile wasn't determined by ownership in old mapping */
+        if (ACCEPT_TABLE(dfa)[state] & 0x80000000)
+                perms.allow |= AA_MAY_CHANGE_PROFILE;
+
+        return perms;
+}
+
+/**
+ * aa_str_perms - find permission that match @name
+ * @dfa: to match against  (MAYBE NULL)
+ * @state: state to start matching in
+ * @name: string to match against dfa  (NOT NULL)
+ * @cond: conditions to consider for permission set computation  (NOT NULL)
+ * @perms: Returns - the permissions found when matching @name
+ *
+ * Returns: the final state in @dfa when beginning @start and walking @name
+ */
+unsigned int aa_str_perms(struct aa_dfa *dfa, unsigned int start,
+                          const char *name, struct path_cond *cond,
+                          struct file_perms *perms)
+{
+        unsigned int state;
+        if (!dfa) {
+                *perms = nullperms;
+                return DFA_NOMATCH;
+        }
+
+        state = aa_dfa_match(dfa, start, name);
+        *perms = compute_perms(dfa, state, cond);
+
+        return state;
+}
+
+/**
+ * is_deleted - test if a file has been completely unlinked
+ * @dentry: dentry of file to test for deletion  (NOT NULL)
+ *
+ * Returns: %1 if deleted else %0
+ */
+static inline bool is_deleted(struct dentry *dentry)
+{
+        if (d_unlinked(dentry) && dentry->d_inode->i_nlink == 0)
+                return 1;
+        return 0;
+}
+
+/**
+ * aa_path_perm - do permissions check & audit for @path
+ * @op: operation being checked
+ * @profile: profile being enforced  (NOT NULL)
+ * @path: path to check permissions of  (NOT NULL)
+ * @flags: any additional path flags beyond what the profile specifies
+ * @request: requested permissions
+ * @cond: conditional info for this request  (NOT NULL)
+ *
+ * Returns: %0 else error if access denied or other error
+ */
+int aa_path_perm(int op, struct aa_profile *profile, struct path *path,
+                 int flags, u32 request, struct path_cond *cond)
+{
+        char *buffer = NULL;
+        struct file_perms perms = {};
+        const char *name, *info = NULL;
+        int error;
+
+        flags |= profile->path_flags | (S_ISDIR(cond->mode) ? PATH_IS_DIR : 0);
+        error = aa_get_name(path, flags, &buffer, &name);
+        if (error) {
+                if (error == -ENOENT && is_deleted(path->dentry)) {
+                        /* Access to open files that are deleted are
+                         * give a pass (implicit delegation)
+                         */
+                        error = 0;
+                        perms.allow = request;
+                } else if (error == -ENOENT)
+                        info = "Failed name lookup - deleted entry";
+                else if (error == -ESTALE)
+                        info = "Failed name lookup - disconnected path";
+                else if (error == -ENAMETOOLONG)
+                        info = "Failed name lookup - name too long";
+                else
+                        info = "Failed name lookup";
+        } else {
+                aa_str_perms(profile->file.dfa, profile->file.start, name, cond,
+                             &perms);
+                if (request & ~perms.allow)
+                        error = -EACCES;
+        }
+        error = aa_audit_file(profile, &perms, GFP_KERNEL, op, request, name,
+                              NULL, cond->uid, info, error);
+        kfree(buffer);
+
+        return error;
+}
+
+/**
+ * xindex_is_subset - helper for aa_path_link
+ * @link: link permission set
+ * @target: target permission set
+ *
+ * test target x permissions are equal OR a subset of link x permissions
+ * this is done as part of the subset test, where a hardlink must have
+ * a subset of permissions that the target has.
+ *
+ * Returns: %1 if subset else %0
+ */
+static inline bool xindex_is_subset(u32 link, u32 target)
+{
+        if (((link & ~AA_X_UNSAFE) != (target & ~AA_X_UNSAFE)) ||
+            ((link & AA_X_UNSAFE) && !(target & AA_X_UNSAFE)))
+                return 0;
+
+        return 1;
+}
+
+/**
+ * aa_path_link - Handle hard link permission check
+ * @profile: the profile being enforced  (NOT NULL)
+ * @old_dentry: the target dentry  (NOT NULL)
+ * @new_dir: directory the new link will be created in  (NOT NULL)
+ * @new_dentry: the link being created  (NOT NULL)
+ *
+ * Handle the permission test for a link & target pair.  Permission
+ * is encoded as a pair where the link permission is determined
+ * first, and if allowed, the target is tested.  The target test
+ * is done from the point of the link match (not start of DFA)
+ * making the target permission dependent on the link permission match.
+ *
+ * The subset test if required forces that permissions granted
+ * on link are a subset of the permission granted to target.
+ *
+ * Returns: %0 if allowed else error
+ */
+int aa_path_link(struct aa_profile *profile, struct dentry *old_dentry,
+                 struct path *new_dir, struct dentry *new_dentry)
+{
+        struct path link = { new_dir->mnt, new_dentry };
+        struct path target = { new_dir->mnt, old_dentry };
+        struct path_cond cond = {
+                old_dentry->d_inode->i_uid,
+                old_dentry->d_inode->i_mode
+        };
+        char *buffer = NULL, *buffer2 = NULL;
+        const char *lname, *tname = NULL, *info = NULL;
+        struct file_perms lperms, perms;
+        u32 request = AA_MAY_LINK;
+        unsigned int state;
+        int error;
+
+        lperms = nullperms;
+
+        /* buffer freed below, lname is pointer in buffer */
+        error = aa_get_name(&link, profile->path_flags, &buffer, &lname);
+        if (error)
+                goto audit;
+
+        /* buffer2 freed below, tname is pointer in buffer2 */
+        error = aa_get_name(&target, profile->path_flags, &buffer2, &tname);
+        if (error)
+                goto audit;
+
+        error = -EACCES;
+        /* aa_str_perms - handles the case of the dfa being NULL */
+        state = aa_str_perms(profile->file.dfa, profile->file.start, lname,
+                             &cond, &lperms);
+
+        if (!(lperms.allow & AA_MAY_LINK))
+                goto audit;
+
+        /* test to see if target can be paired with link */
+        state = aa_dfa_null_transition(profile->file.dfa, state);
+        aa_str_perms(profile->file.dfa, state, tname, &cond, &perms);
+
+        /* force audit/quiet masks for link are stored in the second entry
+         * in the link pair.
+         */
+        lperms.audit = perms.audit;
+        lperms.quiet = perms.quiet;
+        lperms.kill = perms.kill;
+
+        if (!(perms.allow & AA_MAY_LINK)) {
+                info = "target restricted";
+                goto audit;
+        }
+
+        /* done if link subset test is not required */
+        if (!(perms.allow & AA_LINK_SUBSET))
+                goto done_tests;
+
+        /* Do link perm subset test requiring allowed permission on link are a
+         * subset of the allowed permissions on target.
+         */
+        aa_str_perms(profile->file.dfa, profile->file.start, tname, &cond,
+                     &perms);
+
+        /* AA_MAY_LINK is not considered in the subset test */
+        request = lperms.allow & ~AA_MAY_LINK;
+        lperms.allow &= perms.allow | AA_MAY_LINK;
+
+        request |= AA_AUDIT_FILE_MASK & (lperms.allow & ~perms.allow);
+        if (request & ~lperms.allow) {
+                goto audit;
+        } else if ((lperms.allow & MAY_EXEC) &&
+                   !xindex_is_subset(lperms.xindex, perms.xindex)) {
+                lperms.allow &= ~MAY_EXEC;
+                request |= MAY_EXEC;
+                info = "link not subset of target";
+                goto audit;
+        }
+
+done_tests:
+        error = 0;
+
+audit:
+        error = aa_audit_file(profile, &lperms, GFP_KERNEL, OP_LINK, request,
+                              lname, tname, cond.uid, info, error);
+        kfree(buffer);
+        kfree(buffer2);
+
+        return error;
+}
+
+/**
+ * aa_file_perm - do permission revalidation check & audit for @file
+ * @op: operation being checked
+ * @profile: profile being enforced   (NOT NULL)
+ * @file: file to revalidate access permissions on  (NOT NULL)
+ * @request: requested permissions
+ *
+ * Returns: %0 if access allowed else error
+ */
+int aa_file_perm(int op, struct aa_profile *profile, struct file *file,
+                 u32 request)
+{
+        struct path_cond cond = {
+                .uid = file->f_path.dentry->d_inode->i_uid,
+                .mode = file->f_path.dentry->d_inode->i_mode
+        };
+
+        return aa_path_perm(op, profile, &file->f_path, PATH_DELEGATE_DELETED,
+                            request, &cond);
+}
diff --git a/security/apparmor/include/file.h b/security/apparmor/include/file.h
new file mode 100644
index 000000000000..be36feabb16a
--- /dev/null
+++ b/security/apparmor/include/file.h
@@ -0,0 +1,217 @@
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor file mediation function definitions.
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2010 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_FILE_H
+#define __AA_FILE_H
+
+#include <linux/path.h>
+
+#include "domain.h"
+#include "match.h"
+
+struct aa_profile;
+
+/*
+ * We use MAY_EXEC, MAY_WRITE, MAY_READ, MAY_APPEND and the following flags
+ * for profile permissions
+ */
+#define AA_MAY_CREATE                  0x0010
+#define AA_MAY_DELETE                  0x0020
+#define AA_MAY_META_WRITE              0x0040
+#define AA_MAY_META_READ               0x0080
+
+#define AA_MAY_CHMOD                   0x0100
+#define AA_MAY_CHOWN                   0x0200
+#define AA_MAY_LOCK                    0x0400
+#define AA_EXEC_MMAP                   0x0800
+
+#define AA_MAY_LINK                     0x1000
+#define AA_LINK_SUBSET                  AA_MAY_LOCK     /* overlaid */
+#define AA_MAY_ONEXEC                   0x40000000      /* exec allows onexec */
+#define AA_MAY_CHANGE_PROFILE           0x80000000
+#define AA_MAY_CHANGEHAT                0x80000000      /* ctrl auditing only */
+
+#define AA_AUDIT_FILE_MASK      (MAY_READ | MAY_WRITE | MAY_EXEC | MAY_APPEND |\
+                                 AA_MAY_CREATE | AA_MAY_DELETE |        \
+                                 AA_MAY_META_READ | AA_MAY_META_WRITE | \
+                                 AA_MAY_CHMOD | AA_MAY_CHOWN | AA_MAY_LOCK | \
+                                 AA_EXEC_MMAP | AA_MAY_LINK)
+
+/*
+ * The xindex is broken into 3 parts
+ * - index - an index into either the exec name table or the variable table
+ * - exec type - which determines how the executable name and index are used
+ * - flags - which modify how the destination name is applied
+ */
+#define AA_X_INDEX_MASK         0x03ff
+
+#define AA_X_TYPE_MASK          0x0c00
+#define AA_X_TYPE_SHIFT         10
+#define AA_X_NONE               0x0000
+#define AA_X_NAME               0x0400  /* use executable name px */
+#define AA_X_TABLE              0x0800  /* use a specified name ->n# */
+
+#define AA_X_UNSAFE             0x1000
+#define AA_X_CHILD              0x2000  /* make >AA_X_NONE apply to children */
+#define AA_X_INHERIT            0x4000
+#define AA_X_UNCONFINED         0x8000
+
+/* AA_SECURE_X_NEEDED - is passed in the bprm->unsafe field */
+#define AA_SECURE_X_NEEDED      0x8000
+
+/* need to make conditional which ones are being set */
+struct path_cond {
+        uid_t uid;
+        umode_t mode;
+};
+
+/* struct file_perms - file permission
+ * @allow: mask of permissions that are allowed
+ * @audit: mask of permissions to force an audit message for
+ * @quiet: mask of permissions to quiet audit messages for
+ * @kill: mask of permissions that when matched will kill the task
+ * @xindex: exec transition index if @allow contains MAY_EXEC
+ *
+ * The @audit and @queit mask should be mutually exclusive.
+ */
+struct file_perms {
+        u32 allow;
+        u32 audit;
+        u32 quiet;
+        u32 kill;
+        u16 xindex;
+};
+
+extern struct file_perms nullperms;
+
+#define COMBINED_PERM_MASK(X) ((X).allow | (X).audit | (X).quiet | (X).kill)
+
+/* FIXME: split perms from dfa and match this to description
+ *        also add delegation info.
+ */
+static inline u16 dfa_map_xindex(u16 mask)
+{
+        u16 old_index = (mask >> 10) & 0xf;
+        u16 index = 0;
+
+        if (mask & 0x100)
+                index |= AA_X_UNSAFE;
+        if (mask & 0x200)
+                index |= AA_X_INHERIT;
+        if (mask & 0x80)
+                index |= AA_X_UNCONFINED;
+
+        if (old_index == 1) {
+                index |= AA_X_UNCONFINED;
+        } else if (old_index == 2) {
+                index |= AA_X_NAME;
+        } else if (old_index == 3) {
+                index |= AA_X_NAME | AA_X_CHILD;
+        } else {
+                index |= AA_X_TABLE;
+                index |= old_index - 4;
+        }
+
+        return index;
+}
+
+/*
+ * map old dfa inline permissions to new format
+ */
+#define dfa_user_allow(dfa, state) (((ACCEPT_TABLE(dfa)[state]) & 0x7f) | \
+                                    ((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
+#define dfa_user_audit(dfa, state) ((ACCEPT_TABLE2(dfa)[state]) & 0x7f)
+#define dfa_user_quiet(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 7) & 0x7f)
+#define dfa_user_xindex(dfa, state) \
+        (dfa_map_xindex(ACCEPT_TABLE(dfa)[state] & 0x3fff))
+
+#define dfa_other_allow(dfa, state) ((((ACCEPT_TABLE(dfa)[state]) >> 14) & \
+                                      0x7f) |                           \
+                                     ((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
+#define dfa_other_audit(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 14) & 0x7f)
+#define dfa_other_quiet(dfa, state) \
+        ((((ACCEPT_TABLE2(dfa)[state]) >> 7) >> 14) & 0x7f)
+#define dfa_other_xindex(dfa, state) \
+        dfa_map_xindex((ACCEPT_TABLE(dfa)[state] >> 14) & 0x3fff)
+
+int aa_audit_file(struct aa_profile *profile, struct file_perms *perms,
+                  gfp_t gfp, int op, u32 request, const char *name,
+                  const char *target, uid_t ouid, const char *info, int error);
+
+/**
+ * struct aa_file_rules - components used for file rule permissions
+ * @dfa: dfa to match path names and conditionals against
+ * @perms: permission table indexed by the matched state accept entry of @dfa
+ * @trans: transition table for indexed by named x transitions
+ *
+ * File permission are determined by matching a path against @dfa and then
+ * then using the value of the accept entry for the matching state as
+ * an index into @perms.  If a named exec transition is required it is
+ * looked up in the transition table.
+ */
+struct aa_file_rules {
+        unsigned int start;
+        struct aa_dfa *dfa;
+        /* struct perms perms; */
+        struct aa_domain trans;
+        /* TODO: add delegate table */
+};
+
+unsigned int aa_str_perms(struct aa_dfa *dfa, unsigned int start,
+                          const char *name, struct path_cond *cond,
+                          struct file_perms *perms);
+
+int aa_path_perm(int op, struct aa_profile *profile, struct path *path,
+                 int flags, u32 request, struct path_cond *cond);
+
+int aa_path_link(struct aa_profile *profile, struct dentry *old_dentry,
+                 struct path *new_dir, struct dentry *new_dentry);
+
+int aa_file_perm(int op, struct aa_profile *profile, struct file *file,
+                 u32 request);
+
+static inline void aa_free_file_rules(struct aa_file_rules *rules)
+{
+        aa_put_dfa(rules->dfa);
+        aa_free_domain_entries(&rules->trans);
+}
+
+#define ACC_FMODE(x) (("\000\004\002\006"[(x)&O_ACCMODE]) | (((x) << 1) & 0x40))
+
+/* from namei.c */
+#define MAP_OPEN_FLAGS(x) ((((x) + 1) & O_ACCMODE) ? (x) + 1 : (x))
+
+/**
+ * aa_map_file_perms - map file flags to AppArmor permissions
+ * @file: open file to map flags to AppArmor permissions
+ *
+ * Returns: apparmor permission set for the file
+ */
+static inline u32 aa_map_file_to_perms(struct file *file)
+{
+        int flags = MAP_OPEN_FLAGS(file->f_flags);
+        u32 perms = ACC_FMODE(file->f_mode);
+
+        if ((flags & O_APPEND) && (perms & MAY_WRITE))
+                perms = (perms & ~MAY_WRITE) | MAY_APPEND;
+        /* trunc implies write permission */
+        if (flags & O_TRUNC)
+                perms |= MAY_WRITE;
+        if (flags & O_CREAT)
+                perms |= AA_MAY_CREATE;
+
+        return perms;
+}
+
+#endif /* __AA_FILE_H */