apparmor/parser/libapparmor_re/aare_rules.h
John Johansen 444b8e3836 parser: change xattr encoding and allow append_rule to embedd permissions
The current encoding makes every xattr optional and uses this to
propogate the permission from the tail to the individual rule match
points.

This however is wrong. Instead change the encoding so that an xattr
(unless optional) is required to be matched before allowing moving
onto the next xattr match.

The permission is carried on the end on each rule portion file match,
xattr 1, xattr 2, ...

Signed-off-by: John Johansen <john.johansen@canonical.com>
2019-11-26 21:32:08 -08:00

111 lines
2.9 KiB
C++

/*
* (C) 2006, 2007 Andreas Gruenbacher <agruen@suse.de>
* Copyright (c) 2003-2008 Novell, Inc. (All rights reserved)
* Copyright 2009-2012 Canonical Ltd.
*
* The libapparmor library is licensed under the terms of the GNU
* Lesser General Public License, version 2.1. Please see the file
* COPYING.LGPL.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*
* Wrapper around the dfa to convert aa rules into a dfa
*/
#ifndef __LIBAA_RE_RULES_H
#define __LIBAA_RE_RULES_H
#include <stdint.h>
#include "apparmor_re.h"
#include "expr-tree.h"
class UniquePerm {
public:
bool deny;
bool exact_match;
uint32_t perms;
uint32_t audit;
bool operator<(UniquePerm const &rhs)const
{
if (deny == rhs.deny) {
if (exact_match == rhs.exact_match) {
if (perms == rhs.perms)
return audit < rhs.audit;
return perms < rhs.perms;
}
return exact_match;
}
return deny;
}
};
class UniquePermsCache {
public:
typedef map<UniquePerm, Node*> UniquePermMap;
typedef UniquePermMap::iterator iterator;
UniquePermMap nodes;
UniquePermsCache(void) { };
~UniquePermsCache() { clear(); }
void clear()
{
for (iterator i = nodes.begin(); i != nodes.end(); i++) {
delete i->second;
}
nodes.clear();
}
Node *insert(bool deny, uint32_t perms, uint32_t audit,
bool exact_match)
{
UniquePerm tmp = { deny, exact_match, perms, audit };
iterator res = nodes.find(tmp);
if (res == nodes.end()) {
Node *node;
if (deny)
node = new DenyMatchFlag(perms, audit);
else if (exact_match)
node = new ExactMatchFlag(perms, audit);
else
node = new MatchFlag(perms, audit);
pair<iterator, bool> val = nodes.insert(make_pair(tmp, node));
if (val.second == false)
return val.first->second;
return node;
}
return res->second;
}
};
typedef std::map<Node *, Node *> PermExprMap;
class aare_rules {
Node *root;
void add_to_rules(Node *tree, Node *perms);
UniquePermsCache unique_perms;
PermExprMap expr_map;
public:
int reverse;
int rule_count;
aare_rules(void): root(NULL), unique_perms(), expr_map(), reverse(0), rule_count(0) { };
aare_rules(int reverse): root(NULL), unique_perms(), expr_map(), reverse(reverse), rule_count(0) { };
~aare_rules();
bool add_rule(const char *rule, int deny, uint32_t perms,
uint32_t audit, dfaflags_t flags);
bool add_rule_vec(int deny, uint32_t perms, uint32_t audit, int count,
const char **rulev, dfaflags_t flags, bool oob);
bool append_rule(const char *rule, bool oob, bool with_perm, dfaflags_t flags);
void *create_dfa(size_t *size, int *min_match_len, dfaflags_t flags);
};
#endif /* __LIBAA_RE_RULES_H */