security/apparmor/include/file.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * AppArmor security module
   4  *
   5  * This file contains AppArmor file mediation function definitions.
   6  *
   7  * Copyright (C) 1998-2008 Novell/SUSE
   8  * Copyright 2009-2010 Canonical Ltd.
   9  */
  10
  11 #ifndef __AA_FILE_H
  12 #define __AA_FILE_H
  13
  14 #include <linux/spinlock.h>
  15
  16 #include "domain.h"
  17 #include "match.h"
  18 #include "perms.h"
  19
  20 struct aa_policydb;
  21 struct aa_profile;
  22 struct path;
  23
  24 #define mask_mode_t(X) (X & (MAY_EXEC | MAY_WRITE | MAY_READ | MAY_APPEND))
  25
  26 #define AA_AUDIT_FILE_MASK      (MAY_READ | MAY_WRITE | MAY_EXEC | MAY_APPEND |\
  27                                  AA_MAY_CREATE | AA_MAY_DELETE |        \
  28                                  AA_MAY_GETATTR | AA_MAY_SETATTR | \
  29                                  AA_MAY_CHMOD | AA_MAY_CHOWN | AA_MAY_LOCK | \
  30                                  AA_EXEC_MMAP | AA_MAY_LINK)
  31
  32 static inline struct aa_file_ctx *file_ctx(struct file *file)
  33 {
  34         return file->f_security + apparmor_blob_sizes.lbs_file;
  35 }
  36
  37 /* struct aa_file_ctx - the AppArmor context the file was opened in
  38  * @lock: lock to update the ctx
  39  * @label: label currently cached on the ctx
  40  * @perms: the permission the file was opened with
  41  */
  42 struct aa_file_ctx {
  43         spinlock_t lock;
  44         struct aa_label __rcu *label;
  45         u32 allow;
  46 };
  47
  48 /*
  49  * The xindex is broken into 3 parts
  50  * - index - an index into either the exec name table or the variable table
  51  * - exec type - which determines how the executable name and index are used
  52  * - flags - which modify how the destination name is applied
  53  */
  54 #define AA_X_INDEX_MASK         AA_INDEX_MASK
  55
  56 #define AA_X_TYPE_MASK          0x0c000000
  57 #define AA_X_NONE               AA_INDEX_NONE
  58 #define AA_X_NAME               0x04000000 /* use executable name px */
  59 #define AA_X_TABLE              0x08000000 /* use a specified name ->n# */
  60
  61 #define AA_X_UNSAFE             0x10000000
  62 #define AA_X_CHILD              0x20000000
  63 #define AA_X_INHERIT            0x40000000
  64 #define AA_X_UNCONFINED         0x80000000
  65
  66 /* need to make conditional which ones are being set */
  67 struct path_cond {
  68         kuid_t uid;
  69         umode_t mode;
  70 };
  71
  72 #define COMBINED_PERM_MASK(X) ((X).allow | (X).audit | (X).quiet | (X).kill)
  73
  74 int aa_audit_file(const struct cred *cred,
  75                   struct aa_profile *profile, struct aa_perms *perms,
  76                   const char *op, u32 request, const char *name,
  77                   const char *target, struct aa_label *tlabel, kuid_t ouid,
  78                   const char *info, int error);
  79
  80 struct aa_perms *aa_lookup_fperms(struct aa_policydb *file_rules,
  81                                   aa_state_t state, struct path_cond *cond);
  82 aa_state_t aa_str_perms(struct aa_policydb *file_rules, aa_state_t start,
  83                         const char *name, struct path_cond *cond,
  84                         struct aa_perms *perms);
  85
  86 int aa_path_perm(const char *op, const struct cred *subj_cred,
  87                  struct aa_label *label, const struct path *path,
  88                  int flags, u32 request, struct path_cond *cond);
  89
  90 int aa_path_link(const struct cred *subj_cred, struct aa_label *label,
  91                  struct dentry *old_dentry, const struct path *new_dir,
  92                  struct dentry *new_dentry);
  93
  94 int aa_file_perm(const char *op, const struct cred *subj_cred,
  95                  struct aa_label *label, struct file *file,
  96                  u32 request, bool in_atomic);
  97
  98 void aa_inherit_files(const struct cred *cred, struct files_struct *files);
  99
 100
 101 /**
 102  * aa_map_file_perms - map file flags to AppArmor permissions
 103  * @file: open file to map flags to AppArmor permissions
 104  *
 105  * Returns: apparmor permission set for the file
 106  */
 107 static inline u32 aa_map_file_to_perms(struct file *file)
 108 {
 109         int flags = file->f_flags;
 110         u32 perms = 0;
 111
 112         if (file->f_mode & FMODE_WRITE)
 113                 perms |= MAY_WRITE;
 114         if (file->f_mode & FMODE_READ)
 115                 perms |= MAY_READ;
 116
 117         if ((flags & O_APPEND) && (perms & MAY_WRITE))
 118                 perms = (perms & ~MAY_WRITE) | MAY_APPEND;
 119         /* trunc implies write permission */
 120         if (flags & O_TRUNC)
 121                 perms |= MAY_WRITE;
 122         if (flags & O_CREAT)
 123                 perms |= AA_MAY_CREATE;
 124
 125         return perms;
 126 }
 127
 128 #endif /* __AA_FILE_H */