109 lines
2.9 KiB
C
109 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* AppArmor security module
|
|
*
|
|
* This file contains AppArmor ipc mediation
|
|
*
|
|
* Copyright (C) 1998-2008 Novell/SUSE
|
|
* Copyright 2009-2017 Canonical Ltd.
|
|
*/
|
|
|
|
#include <linux/gfp.h>
|
|
|
|
#include "include/audit.h"
|
|
#include "include/capability.h"
|
|
#include "include/cred.h"
|
|
#include "include/policy.h"
|
|
#include "include/ipc.h"
|
|
#include "include/sig_names.h"
|
|
|
|
|
|
static inline int map_signal_num(int sig)
|
|
{
|
|
if (sig > SIGRTMAX)
|
|
return SIGUNKNOWN;
|
|
else if (sig >= SIGRTMIN)
|
|
return sig - SIGRTMIN + SIGRT_BASE;
|
|
else if (sig < MAXMAPPED_SIG)
|
|
return sig_map[sig];
|
|
return SIGUNKNOWN;
|
|
}
|
|
|
|
/**
|
|
* audit_signal_mask - convert mask to permission string
|
|
* @mask: permission mask to convert
|
|
*
|
|
* Returns: pointer to static string
|
|
*/
|
|
static const char *audit_signal_mask(u32 mask)
|
|
{
|
|
if (mask & MAY_READ)
|
|
return "receive";
|
|
if (mask & MAY_WRITE)
|
|
return "send";
|
|
return "";
|
|
}
|
|
|
|
/**
|
|
* audit_cb - call back for signal specific audit fields
|
|
* @ab: audit_buffer (NOT NULL)
|
|
* @va: audit struct to audit values of (NOT NULL)
|
|
*/
|
|
static void audit_signal_cb(struct audit_buffer *ab, void *va)
|
|
{
|
|
struct common_audit_data *sa = va;
|
|
|
|
if (aad(sa)->request & AA_SIGNAL_PERM_MASK) {
|
|
audit_log_format(ab, " requested_mask=\"%s\"",
|
|
audit_signal_mask(aad(sa)->request));
|
|
if (aad(sa)->denied & AA_SIGNAL_PERM_MASK) {
|
|
audit_log_format(ab, " denied_mask=\"%s\"",
|
|
audit_signal_mask(aad(sa)->denied));
|
|
}
|
|
}
|
|
if (aad(sa)->signal == SIGUNKNOWN)
|
|
audit_log_format(ab, "signal=unknown(%d)",
|
|
aad(sa)->unmappedsig);
|
|
else if (aad(sa)->signal < MAXMAPPED_SIGNAME)
|
|
audit_log_format(ab, " signal=%s", sig_names[aad(sa)->signal]);
|
|
else
|
|
audit_log_format(ab, " signal=rtmin+%d",
|
|
aad(sa)->signal - SIGRT_BASE);
|
|
audit_log_format(ab, " peer=");
|
|
aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,
|
|
FLAGS_NONE, GFP_ATOMIC);
|
|
}
|
|
|
|
static int profile_signal_perm(struct aa_profile *profile,
|
|
struct aa_label *peer, u32 request,
|
|
struct common_audit_data *sa)
|
|
{
|
|
struct aa_perms perms;
|
|
unsigned int state;
|
|
|
|
if (profile_unconfined(profile) ||
|
|
!PROFILE_MEDIATES(profile, AA_CLASS_SIGNAL))
|
|
return 0;
|
|
|
|
aad(sa)->peer = peer;
|
|
/* TODO: secondary cache check <profile, profile, perm> */
|
|
state = aa_dfa_next(profile->policy.dfa,
|
|
profile->policy.start[AA_CLASS_SIGNAL],
|
|
aad(sa)->signal);
|
|
aa_label_match(profile, peer, state, false, request, &perms);
|
|
aa_apply_modes_to_perms(profile, &perms);
|
|
return aa_check_perms(profile, &perms, request, sa, audit_signal_cb);
|
|
}
|
|
|
|
int aa_may_signal(struct aa_label *sender, struct aa_label *target, int sig)
|
|
{
|
|
struct aa_profile *profile;
|
|
DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SIGNAL);
|
|
|
|
aad(&sa)->signal = map_signal_num(sig);
|
|
aad(&sa)->unmappedsig = sig;
|
|
return xcheck_labels(sender, target, profile,
|
|
profile_signal_perm(profile, target, MAY_WRITE, &sa),
|
|
profile_signal_perm(profile, sender, MAY_READ, &sa));
|
|
}
|