// SPDX-License-Identifier: GPL-2.0-only /* * AppArmor security module * * This file contains AppArmor mediation of files * * Copyright (C) 1998-2008 Novell/SUSE * Copyright 2009-2010 Canonical Ltd. */ #include <linux/tty.h> #include <linux/fdtable.h> #include <linux/file.h> #include <linux/fs.h> #include <linux/mount.h> #include "include/apparmor.h" #include "include/audit.h" #include "include/cred.h" #include "include/file.h" #include "include/match.h" #include "include/net.h" #include "include/path.h" #include "include/policy.h" #include "include/label.h" static u32 map_mask_to_chr_mask(u32 mask) { … } /** * 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) { … } /** * aa_audit_file - handle the auditing of file operations * @subj_cred: cred of the subject * @profile: the profile being enforced (NOT NULL) * @perms: the permissions computed for the request (NOT NULL) * @op: operation being mediated * @request: permissions requested * @name: name of object being mediated (MAYBE NULL) * @target: name of target (MAYBE NULL) * @tlabel: target label (MAY BE 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(const struct cred *subj_cred, struct aa_profile *profile, struct aa_perms *perms, const char *op, u32 request, const char *name, const char *target, struct aa_label *tlabel, kuid_t ouid, const char *info, int error) { … } static int path_name(const char *op, const struct cred *subj_cred, struct aa_label *label, const struct path *path, int flags, char *buffer, const char **name, struct path_cond *cond, u32 request) { … } struct aa_perms default_perms = …; /** * aa_lookup_fperms - convert dfa compressed perms to internal perms * @file_rules: the aa_policydb to lookup perms for (NOT NULL) * @state: state in dfa * @cond: conditions to consider (NOT NULL) * * TODO: convert from dfa + state to permission entry * * Returns: a pointer to a file permission set */ struct aa_perms *aa_lookup_fperms(struct aa_policydb *file_rules, aa_state_t state, struct path_cond *cond) { … } /** * aa_str_perms - find permission that match @name * @file_rules: the aa_policydb to match against (NOT NULL) * @start: 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 */ aa_state_t aa_str_perms(struct aa_policydb *file_rules, aa_state_t start, const char *name, struct path_cond *cond, struct aa_perms *perms) { … } static int __aa_path_perm(const char *op, const struct cred *subj_cred, struct aa_profile *profile, const char *name, u32 request, struct path_cond *cond, int flags, struct aa_perms *perms) { … } static int profile_path_perm(const char *op, const struct cred *subj_cred, struct aa_profile *profile, const struct path *path, char *buffer, u32 request, struct path_cond *cond, int flags, struct aa_perms *perms) { … } /** * aa_path_perm - do permissions check & audit for @path * @op: operation being checked * @subj_cred: subject cred * @label: 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(const char *op, const struct cred *subj_cred, struct aa_label *label, const struct path *path, int flags, u32 request, struct path_cond *cond) { … } /** * 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: true if subset else false */ static inline bool xindex_is_subset(u32 link, u32 target) { … } static int profile_path_link(const struct cred *subj_cred, struct aa_profile *profile, const struct path *link, char *buffer, const struct path *target, char *buffer2, struct path_cond *cond) { … } /** * aa_path_link - Handle hard link permission check * @subj_cred: subject cred * @label: the label 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(const struct cred *subj_cred, struct aa_label *label, struct dentry *old_dentry, const struct path *new_dir, struct dentry *new_dentry) { … } static void update_file_ctx(struct aa_file_ctx *fctx, struct aa_label *label, u32 request) { … } static int __file_path_perm(const char *op, const struct cred *subj_cred, struct aa_label *label, struct aa_label *flabel, struct file *file, u32 request, u32 denied, bool in_atomic) { … } static int __file_sock_perm(const char *op, const struct cred *subj_cred, struct aa_label *label, struct aa_label *flabel, struct file *file, u32 request, u32 denied) { … } /** * aa_file_perm - do permission revalidation check & audit for @file * @op: operation being checked * @subj_cred: subject cred * @label: label being enforced (NOT NULL) * @file: file to revalidate access permissions on (NOT NULL) * @request: requested permissions * @in_atomic: whether allocations need to be done in atomic context * * Returns: %0 if access allowed else error */ int aa_file_perm(const char *op, const struct cred *subj_cred, struct aa_label *label, struct file *file, u32 request, bool in_atomic) { … } static void revalidate_tty(const struct cred *subj_cred, struct aa_label *label) { … } struct cred_label { … }; static int match_file(const void *p, struct file *file, unsigned int fd) { … } /* based on selinux's flush_unauthorized_files */ void aa_inherit_files(const struct cred *cred, struct files_struct *files) { … }