 dd0c6e86f6
			
		
	
	
	dd0c6e86f6
	
	
	
		
			
			Mediation is based off of the cred but auditing includes the current task which may not be related to the actual request. Signed-off-by: John Johansen <john.johansen@canonical.com>
		
			
				
	
	
		
			143 lines
		
	
	
	
		
			3.7 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			143 lines
		
	
	
	
		
			3.7 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * AppArmor security module
 | |
|  *
 | |
|  * This file contains AppArmor capability mediation functions
 | |
|  *
 | |
|  * Copyright (C) 1998-2008 Novell/SUSE
 | |
|  * Copyright 2009-2010 Canonical Ltd.
 | |
|  *
 | |
|  * This program is free software; you can redistribute it and/or
 | |
|  * modify it under the terms of the GNU General Public License as
 | |
|  * published by the Free Software Foundation, version 2 of the
 | |
|  * License.
 | |
|  */
 | |
| 
 | |
| #include <linux/capability.h>
 | |
| #include <linux/errno.h>
 | |
| #include <linux/gfp.h>
 | |
| 
 | |
| #include "include/apparmor.h"
 | |
| #include "include/capability.h"
 | |
| #include "include/context.h"
 | |
| #include "include/policy.h"
 | |
| #include "include/audit.h"
 | |
| 
 | |
| /*
 | |
|  * Table of capability names: we generate it from capabilities.h.
 | |
|  */
 | |
| #include "capability_names.h"
 | |
| 
 | |
| struct aa_fs_entry aa_fs_entry_caps[] = {
 | |
| 	AA_FS_FILE_STRING("mask", AA_FS_CAPS_MASK),
 | |
| 	{ }
 | |
| };
 | |
| 
 | |
| struct audit_cache {
 | |
| 	struct aa_profile *profile;
 | |
| 	kernel_cap_t caps;
 | |
| };
 | |
| 
 | |
| static DEFINE_PER_CPU(struct audit_cache, audit_cache);
 | |
| 
 | |
| /**
 | |
|  * audit_cb - call back for capability components of audit struct
 | |
|  * @ab - audit buffer   (NOT NULL)
 | |
|  * @va - audit struct to audit data from  (NOT NULL)
 | |
|  */
 | |
| static void audit_cb(struct audit_buffer *ab, void *va)
 | |
| {
 | |
| 	struct common_audit_data *sa = va;
 | |
| 	audit_log_format(ab, " capname=");
 | |
| 	audit_log_untrustedstring(ab, capability_names[sa->u.cap]);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * audit_caps - audit a capability
 | |
|  * @profile: profile being tested for confinement (NOT NULL)
 | |
|  * @cap: capability tested
 | |
|  * @error: error code returned by test
 | |
|  *
 | |
|  * Do auditing of capability and handle, audit/complain/kill modes switching
 | |
|  * and duplicate message elimination.
 | |
|  *
 | |
|  * Returns: 0 or sa->error on success,  error code on failure
 | |
|  */
 | |
| static int audit_caps(struct aa_profile *profile, int cap, int error)
 | |
| {
 | |
| 	struct audit_cache *ent;
 | |
| 	int type = AUDIT_APPARMOR_AUTO;
 | |
| 	struct common_audit_data sa;
 | |
| 	struct apparmor_audit_data aad = {0,};
 | |
| 	sa.type = LSM_AUDIT_DATA_CAP;
 | |
| 	sa.aad = &aad;
 | |
| 	sa.u.cap = cap;
 | |
| 	sa.aad->op = OP_CAPABLE;
 | |
| 	sa.aad->error = error;
 | |
| 
 | |
| 	if (likely(!error)) {
 | |
| 		/* test if auditing is being forced */
 | |
| 		if (likely((AUDIT_MODE(profile) != AUDIT_ALL) &&
 | |
| 			   !cap_raised(profile->caps.audit, cap)))
 | |
| 			return 0;
 | |
| 		type = AUDIT_APPARMOR_AUDIT;
 | |
| 	} else if (KILL_MODE(profile) ||
 | |
| 		   cap_raised(profile->caps.kill, cap)) {
 | |
| 		type = AUDIT_APPARMOR_KILL;
 | |
| 	} else if (cap_raised(profile->caps.quiet, cap) &&
 | |
| 		   AUDIT_MODE(profile) != AUDIT_NOQUIET &&
 | |
| 		   AUDIT_MODE(profile) != AUDIT_ALL) {
 | |
| 		/* quiet auditing */
 | |
| 		return error;
 | |
| 	}
 | |
| 
 | |
| 	/* Do simple duplicate message elimination */
 | |
| 	ent = &get_cpu_var(audit_cache);
 | |
| 	if (profile == ent->profile && cap_raised(ent->caps, cap)) {
 | |
| 		put_cpu_var(audit_cache);
 | |
| 		if (COMPLAIN_MODE(profile))
 | |
| 			return complain_error(error);
 | |
| 		return error;
 | |
| 	} else {
 | |
| 		aa_put_profile(ent->profile);
 | |
| 		ent->profile = aa_get_profile(profile);
 | |
| 		cap_raise(ent->caps, cap);
 | |
| 	}
 | |
| 	put_cpu_var(audit_cache);
 | |
| 
 | |
| 	return aa_audit(type, profile, GFP_ATOMIC, &sa, audit_cb);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * profile_capable - test if profile allows use of capability @cap
 | |
|  * @profile: profile being enforced    (NOT NULL, NOT unconfined)
 | |
|  * @cap: capability to test if allowed
 | |
|  *
 | |
|  * Returns: 0 if allowed else -EPERM
 | |
|  */
 | |
| static int profile_capable(struct aa_profile *profile, int cap)
 | |
| {
 | |
| 	return cap_raised(profile->caps.allow, cap) ? 0 : -EPERM;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * aa_capable - test permission to use capability
 | |
|  * @profile: profile being tested against (NOT NULL)
 | |
|  * @cap: capability to be tested
 | |
|  * @audit: whether an audit record should be generated
 | |
|  *
 | |
|  * Look up capability in profile capability set.
 | |
|  *
 | |
|  * Returns: 0 on success, or else an error code.
 | |
|  */
 | |
| int aa_capable(struct aa_profile *profile, int cap, int audit)
 | |
| {
 | |
| 	int error = profile_capable(profile, cap);
 | |
| 
 | |
| 	if (!audit) {
 | |
| 		if (COMPLAIN_MODE(profile))
 | |
| 			return complain_error(error);
 | |
| 		return error;
 | |
| 	}
 | |
| 
 | |
| 	return audit_caps(profile, cap, error);
 | |
| }
 |