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-rw-r--r--security/apparmor/include/match.h141
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diff --git a/security/apparmor/include/match.h b/security/apparmor/include/match.h
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+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor policy dfa matching engine definitions.
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2012 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.
+ */
+
+#ifndef __AA_MATCH_H
+#define __AA_MATCH_H
+
+#include <linux/kref.h>
+
+#define DFA_NOMATCH 0
+#define DFA_START 1
+
+
+/**
+ * The format used for transition tables is based on the GNU flex table
+ * file format (--tables-file option; see Table File Format in the flex
+ * info pages and the flex sources for documentation). The magic number
+ * used in the header is 0x1B5E783D instead of 0xF13C57B1 though, because
+ * new tables have been defined and others YY_ID_CHK (check) and YY_ID_DEF
+ * (default) tables are used slightly differently (see the apparmor-parser
+ * package).
+ *
+ *
+ * The data in the packed dfa is stored in network byte order, and the tables
+ * are arranged for flexibility. We convert the table data to host native
+ * byte order.
+ *
+ * The dfa begins with a table set header, and is followed by the actual
+ * tables.
+ */
+
+#define YYTH_MAGIC 0x1B5E783D
+
+struct table_set_header {
+ u32 th_magic; /* YYTH_MAGIC */
+ u32 th_hsize;
+ u32 th_ssize;
+ u16 th_flags;
+ char th_version[];
+};
+
+/* The YYTD_ID are one less than flex table mappings. The flex id
+ * has 1 subtracted at table load time, this allows us to directly use the
+ * ID's as indexes.
+ */
+#define YYTD_ID_ACCEPT 0
+#define YYTD_ID_BASE 1
+#define YYTD_ID_CHK 2
+#define YYTD_ID_DEF 3
+#define YYTD_ID_EC 4
+#define YYTD_ID_META 5
+#define YYTD_ID_ACCEPT2 6
+#define YYTD_ID_NXT 7
+#define YYTD_ID_TSIZE 8
+
+#define YYTD_DATA8 1
+#define YYTD_DATA16 2
+#define YYTD_DATA32 4
+#define YYTD_DATA64 8
+
+/* ACCEPT & ACCEPT2 tables gets 6 dedicated flags, YYTD_DATAX define the
+ * first flags
+ */
+#define ACCEPT1_FLAGS(X) ((X) & 0x3f)
+#define ACCEPT2_FLAGS(X) ACCEPT1_FLAGS((X) >> YYTD_ID_ACCEPT2)
+#define TO_ACCEPT1_FLAG(X) ACCEPT1_FLAGS(X)
+#define TO_ACCEPT2_FLAG(X) (ACCEPT1_FLAGS(X) << YYTD_ID_ACCEPT2)
+#define DFA_FLAG_VERIFY_STATES 0x1000
+
+struct table_header {
+ u16 td_id;
+ u16 td_flags;
+ u32 td_hilen;
+ u32 td_lolen;
+ char td_data[];
+};
+
+#define DEFAULT_TABLE(DFA) ((u16 *)((DFA)->tables[YYTD_ID_DEF]->td_data))
+#define BASE_TABLE(DFA) ((u32 *)((DFA)->tables[YYTD_ID_BASE]->td_data))
+#define NEXT_TABLE(DFA) ((u16 *)((DFA)->tables[YYTD_ID_NXT]->td_data))
+#define CHECK_TABLE(DFA) ((u16 *)((DFA)->tables[YYTD_ID_CHK]->td_data))
+#define EQUIV_TABLE(DFA) ((u8 *)((DFA)->tables[YYTD_ID_EC]->td_data))
+#define ACCEPT_TABLE(DFA) ((u32 *)((DFA)->tables[YYTD_ID_ACCEPT]->td_data))
+#define ACCEPT_TABLE2(DFA) ((u32 *)((DFA)->tables[YYTD_ID_ACCEPT2]->td_data))
+
+struct aa_dfa {
+ struct kref count;
+ u16 flags;
+ struct table_header *tables[YYTD_ID_TSIZE];
+};
+
+#define byte_to_byte(X) (X)
+
+#define UNPACK_ARRAY(TABLE, BLOB, LEN, TYPE, NTOHX) \
+ do { \
+ typeof(LEN) __i; \
+ TYPE *__t = (TYPE *) TABLE; \
+ TYPE *__b = (TYPE *) BLOB; \
+ for (__i = 0; __i < LEN; __i++) { \
+ __t[__i] = NTOHX(__b[__i]); \
+ } \
+ } while (0)
+
+static inline size_t table_size(size_t len, size_t el_size)
+{
+ return ALIGN(sizeof(struct table_header) + len * el_size, 8);
+}
+
+struct aa_dfa *aa_dfa_unpack(void *blob, size_t size, int flags);
+unsigned int aa_dfa_match_len(struct aa_dfa *dfa, unsigned int start,
+ const char *str, int len);
+unsigned int aa_dfa_match(struct aa_dfa *dfa, unsigned int start,
+ const char *str);
+unsigned int aa_dfa_next(struct aa_dfa *dfa, unsigned int state,
+ const char c);
+
+void aa_dfa_free_kref(struct kref *kref);
+
+/**
+ * aa_put_dfa - put a dfa refcount
+ * @dfa: dfa to put refcount (MAYBE NULL)
+ *
+ * Requires: if @dfa != NULL that a valid refcount be held
+ */
+static inline void aa_put_dfa(struct aa_dfa *dfa)
+{
+ if (dfa)
+ kref_put(&dfa->count, aa_dfa_free_kref);
+}
+
+#endif /* __AA_MATCH_H */