Signed-off-by: John Johansen <john.johansen@canonical.com> Acked-by: Steve Beattie <sbeattie@ubuntu.com>
		
			
				
	
	
		
			112 lines
		
	
	
	
		
			3.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			112 lines
		
	
	
	
		
			3.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * AppArmor security module
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 *
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 * This file contains AppArmor ipc mediation
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 *
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 * Copyright (C) 1998-2008 Novell/SUSE
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 * Copyright 2009-2010 Canonical Ltd.
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 *
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 * This program is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU General Public License as
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 * published by the Free Software Foundation, version 2 of the
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 * License.
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 */
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#include <linux/gfp.h>
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#include <linux/ptrace.h>
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#include "include/audit.h"
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#include "include/capability.h"
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#include "include/context.h"
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#include "include/policy.h"
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#include "include/ipc.h"
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/* call back to audit ptrace fields */
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static void audit_cb(struct audit_buffer *ab, void *va)
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{
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	struct common_audit_data *sa = va;
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	audit_log_format(ab, " target=");
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	audit_log_untrustedstring(ab, sa->aad->target);
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}
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/**
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 * aa_audit_ptrace - do auditing for ptrace
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 * @profile: profile being enforced  (NOT NULL)
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 * @target: profile being traced (NOT NULL)
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 * @error: error condition
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 *
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 * Returns: %0 or error code
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 */
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static int aa_audit_ptrace(struct aa_profile *profile,
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			   struct aa_profile *target, int error)
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{
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	struct common_audit_data sa;
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	struct apparmor_audit_data aad = {0,};
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	sa.type = LSM_AUDIT_DATA_NONE;
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	sa.aad = &aad;
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	aad.op = OP_PTRACE;
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	aad.target = target;
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	aad.error = error;
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	return aa_audit(AUDIT_APPARMOR_AUTO, profile, GFP_ATOMIC, &sa,
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			audit_cb);
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}
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/**
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 * aa_may_ptrace - test if tracer task can trace the tracee
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 * @tracer_task: task who will do the tracing  (NOT NULL)
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 * @tracer: profile of the task doing the tracing  (NOT NULL)
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 * @tracee: task to be traced
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 * @mode: whether PTRACE_MODE_READ || PTRACE_MODE_ATTACH
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 *
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 * Returns: %0 else error code if permission denied or error
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 */
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int aa_may_ptrace(struct task_struct *tracer_task, struct aa_profile *tracer,
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		  struct aa_profile *tracee, unsigned int mode)
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{
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	/* TODO: currently only based on capability, not extended ptrace
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	 *       rules,
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	 *       Test mode for PTRACE_MODE_READ || PTRACE_MODE_ATTACH
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	 */
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	if (unconfined(tracer) || tracer == tracee)
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		return 0;
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	/* log this capability request */
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	return aa_capable(tracer_task, tracer, CAP_SYS_PTRACE, 1);
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}
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/**
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 * aa_ptrace - do ptrace permission check and auditing
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 * @tracer: task doing the tracing (NOT NULL)
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 * @tracee: task being traced (NOT NULL)
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 * @mode: ptrace mode either PTRACE_MODE_READ || PTRACE_MODE_ATTACH
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 *
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 * Returns: %0 else error code if permission denied or error
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 */
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int aa_ptrace(struct task_struct *tracer, struct task_struct *tracee,
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	      unsigned int mode)
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{
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	/*
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	 * tracer can ptrace tracee when
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	 * - tracer is unconfined ||
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	 *   - tracer is in complain mode
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	 *   - tracer has rules allowing it to trace tracee currently this is:
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	 *       - confined by the same profile ||
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	 *       - tracer profile has CAP_SYS_PTRACE
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	 */
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	struct aa_profile *tracer_p = aa_get_task_profile(tracer);
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	int error = 0;
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	if (!unconfined(tracer_p)) {
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		struct aa_profile *tracee_p = aa_get_task_profile(tracee);
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		error = aa_may_ptrace(tracer, tracer_p, tracee_p, mode);
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		error = aa_audit_ptrace(tracer_p, tracee_p, error);
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		aa_put_profile(tracee_p);
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	}
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	aa_put_profile(tracer_p);
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	return error;
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}
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