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 * aa_alloc_file_ctx - allocate file_ctx 50 * @label: initial label of task creating the file 51 * @gfp: gfp flags for allocation 52 * 53 * Returns: file_ctx or NULL on failure 54 */ 55 static inline struct aa_file_ctx *aa_alloc_file_ctx(struct aa_label *label, 56 gfp_t gfp) 57 { 58 struct aa_file_ctx *ctx; 59 60 ctx = kzalloc(sizeof(struct aa_file_ctx), gfp); 61 if (ctx) { 62 spin_lock_init(&ctx->lock); 63 rcu_assign_pointer(ctx->label, aa_get_label(label)); 64 } 65 return ctx; 66 } 67 68 /** 69 * aa_free_file_ctx - free a file_ctx 70 * @ctx: file_ctx to free (MAYBE_NULL) 71 */ 72 static inline void aa_free_file_ctx(struct aa_file_ctx *ctx) 73 { 74 if (ctx) { 75 aa_put_label(rcu_access_pointer(ctx->label)); 76 kfree_sensitive(ctx); 77 } 78 } 79 80 static inline struct aa_label *aa_get_file_label(struct aa_file_ctx *ctx) 81 { 82 return aa_get_label_rcu(&ctx->label); 83 } 84 85 /* 86 * The xindex is broken into 3 parts 87 * - index - an index into either the exec name table or the variable table 88 * - exec type - which determines how the executable name and index are used 89 * - flags - which modify how the destination name is applied 90 */ 91 #define AA_X_INDEX_MASK AA_INDEX_MASK 92 93 #define AA_X_TYPE_MASK 0x0c000000 94 #define AA_X_NONE AA_INDEX_NONE 95 #define AA_X_NAME 0x04000000 /* use executable name px */ 96 #define AA_X_TABLE 0x08000000 /* use a specified name ->n# */ 97 98 #define AA_X_UNSAFE 0x10000000 99 #define AA_X_CHILD 0x20000000 100 #define AA_X_INHERIT 0x40000000 101 #define AA_X_UNCONFINED 0x80000000 102 103 /* need to make conditional which ones are being set */ 104 struct path_cond { 105 kuid_t uid; 106 umode_t mode; 107 }; 108 109 #define COMBINED_PERM_MASK(X) ((X).allow | (X).audit | (X).quiet | (X).kill) 110 111 int aa_audit_file(struct aa_profile *profile, struct aa_perms *perms, 112 const char *op, u32 request, const char *name, 113 const char *target, struct aa_label *tlabel, kuid_t ouid, 114 const char *info, int error); 115 116 struct aa_perms *aa_lookup_fperms(struct aa_policydb *file_rules, 117 aa_state_t state, struct path_cond *cond); 118 aa_state_t aa_str_perms(struct aa_policydb *file_rules, aa_state_t start, 119 const char *name, struct path_cond *cond, 120 struct aa_perms *perms); 121 122 int aa_path_perm(const char *op, struct aa_label *label, 123 const struct path *path, int flags, u32 request, 124 struct path_cond *cond); 125 126 int aa_path_link(struct aa_label *label, struct dentry *old_dentry, 127 const struct path *new_dir, struct dentry *new_dentry); 128 129 int aa_file_perm(const char *op, struct aa_label *label, struct file *file, 130 u32 request, bool in_atomic); 131 132 void aa_inherit_files(const struct cred *cred, struct files_struct *files); 133 134 135 /** 136 * aa_map_file_perms - map file flags to AppArmor permissions 137 * @file: open file to map flags to AppArmor permissions 138 * 139 * Returns: apparmor permission set for the file 140 */ 141 static inline u32 aa_map_file_to_perms(struct file *file) 142 { 143 int flags = file->f_flags; 144 u32 perms = 0; 145 146 if (file->f_mode & FMODE_WRITE) 147 perms |= MAY_WRITE; 148 if (file->f_mode & FMODE_READ) 149 perms |= MAY_READ; 150 151 if ((flags & O_APPEND) && (perms & MAY_WRITE)) 152 perms = (perms & ~MAY_WRITE) | MAY_APPEND; 153 /* trunc implies write permission */ 154 if (flags & O_TRUNC) 155 perms |= MAY_WRITE; 156 if (flags & O_CREAT) 157 perms |= AA_MAY_CREATE; 158 159 return perms; 160 } 161 162 #endif /* __AA_FILE_H */ 163