linux/security/apparmor/task.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * AppArmor security module
 *
 * This file contains AppArmor task related definitions and mediation
 *
 * Copyright 2017 Canonical Ltd.
 *
 * TODO
 * If a task uses change_hat it currently does not return to the old
 * cred or task context but instead creates a new one.  Ideally the task
 * should return to the previous cred if it has not been modified.
 */

#include <linux/gfp.h>
#include <linux/ptrace.h>

#include "include/audit.h"
#include "include/cred.h"
#include "include/policy.h"
#include "include/task.h"

/**
 * aa_get_task_label - Get another task's label
 * @task: task to query  (NOT NULL)
 *
 * Returns: counted reference to @task's label
 */
struct aa_label *aa_get_task_label(struct task_struct *task)
{ … }

/**
 * aa_replace_current_label - replace the current tasks label
 * @label: new label  (NOT NULL)
 *
 * Returns: 0 or error on failure
 */
int aa_replace_current_label(struct aa_label *label)
{ … }


/**
 * aa_set_current_onexec - set the tasks change_profile to happen onexec
 * @label: system label to set at exec  (MAYBE NULL to clear value)
 * @stack: whether stacking should be done
 */
void aa_set_current_onexec(struct aa_label *label, bool stack)
{ … }

/**
 * aa_set_current_hat - set the current tasks hat
 * @label: label to set as the current hat  (NOT NULL)
 * @token: token value that must be specified to change from the hat
 *
 * Do switch of tasks hat.  If the task is currently in a hat
 * validate the token to match.
 *
 * Returns: 0 or error on failure
 */
int aa_set_current_hat(struct aa_label *label, u64 token)
{ … }

/**
 * aa_restore_previous_label - exit from hat context restoring previous label
 * @token: the token that must be matched to exit hat context
 *
 * Attempt to return out of a hat to the previous label.  The token
 * must match the stored token value.
 *
 * Returns: 0 or error of failure
 */
int aa_restore_previous_label(u64 token)
{ … }

/**
 * audit_ptrace_mask - convert mask to permission string
 * @mask: permission mask to convert
 *
 * Returns: pointer to static string
 */
static const char *audit_ptrace_mask(u32 mask)
{ … }

/* call back to audit ptrace fields */
static void audit_ptrace_cb(struct audit_buffer *ab, void *va)
{ … }

/* assumes check for RULE_MEDIATES is already done */
/* TODO: conditionals */
static int profile_ptrace_perm(const struct cred *cred,
			       struct aa_profile *profile,
			       struct aa_label *peer, u32 request,
			       struct apparmor_audit_data *ad)
{ … }

static int profile_tracee_perm(const struct cred *cred,
			       struct aa_profile *tracee,
			       struct aa_label *tracer, u32 request,
			       struct apparmor_audit_data *ad)
{ … }

static int profile_tracer_perm(const struct cred *cred,
			       struct aa_profile *tracer,
			       struct aa_label *tracee, u32 request,
			       struct apparmor_audit_data *ad)
{ … }

/**
 * aa_may_ptrace - test if tracer task can trace the tracee
 * @tracer_cred: cred of task doing the tracing  (NOT NULL)
 * @tracer: label of the task doing the tracing  (NOT NULL)
 * @tracee_cred: cred of task to be traced
 * @tracee: task label to be traced
 * @request: permission request
 *
 * Returns: %0 else error code if permission denied or error
 */
int aa_may_ptrace(const struct cred *tracer_cred, struct aa_label *tracer,
		  const struct cred *tracee_cred, struct aa_label *tracee,
		  u32 request)
{ … }

/* call back to audit ptrace fields */
static void audit_ns_cb(struct audit_buffer *ab, void *va)
{ … }

int aa_profile_ns_perm(struct aa_profile *profile,
		       struct apparmor_audit_data *ad,
		       u32 request)
{ … }