verified_exec.h revision 1.10 1 /* $NetBSD: verified_exec.h,v 1.10 2005/05/22 22:34:01 elad Exp $ */
2
3 /*-
4 * Copyright 2005 Elad Efrat <elad (at) bsd.org.il>
5 * Copyright 2005 Brett Lymn <blymn (at) netbsd.org>
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Brett Lymn and Elad Efrat
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Neither the name of The NetBSD Foundation nor the names of its
16 * contributors may be used to endorse or promote products derived
17 * from this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: verified_exec.h,v 1.10 2005/05/22 22:34:01 elad Exp $");
34
35 /*
36 *
37 * Definitions for the Verified Executables kernel function.
38 *
39 */
40 #include <sys/param.h>
41 #include <sys/hash.h>
42
43 #ifndef V_EXEC_H
44 #define V_EXEC_H 1
45
46 /* Max length of the fingerprint type string, including terminating \0 char */
47 #define VERIEXEC_TYPE_MAXLEN 9
48
49 struct veriexec_params {
50 unsigned char type;
51 unsigned char fp_type[VERIEXEC_TYPE_MAXLEN]; /* type of fingerprint
52 this is */
53 char file[MAXPATHLEN];
54 unsigned int size; /* number of bytes in the fingerprint */
55 unsigned char *fingerprint;
56 };
57
58 struct veriexec_sizing_params {
59 dev_t dev;
60 size_t hash_size;
61 };
62
63 /*
64 * Types of veriexec inodes we can have
65 */
66 #define VERIEXEC_DIRECT 0 /* Allow direct execution */
67 #define VERIEXEC_INDIRECT 1 /* Only allow indirect execution */
68 #define VERIEXEC_FILE 2 /* Fingerprint of a plain file */
69
70 #define VERIEXEC_LOAD _IOW('S', 0x1, struct veriexec_params)
71 #define VERIEXEC_TABLESIZE _IOW('S', 0x2, struct veriexec_sizing_params)
72
73 /* Verified exec sysctl objects. */
74 #define VERIEXEC_VERBOSE 1 /* Verbosity level. */
75 #define VERIEXEC_STRICT 2 /* Strict mode level. */
76 #define VERIEXEC_ALGORITHMS 3 /* Supported hashing algorithms. */
77 #define VERIEXEC_COUNT 4 /* # of fingerprinted files on device. */
78
79 #ifdef _KERNEL
80 void veriexecattach(struct device *, struct device *, void *);
81 int veriexecopen(dev_t, int, int, struct proc *);
82 int veriexecclose(dev_t, int, int, struct proc *);
83 int veriexecioctl(dev_t, u_long, caddr_t, int, struct proc *);
84
85 /* defined in kern_verifiedexec.c */
86 extern char *veriexec_fp_names;
87 extern int veriexec_verbose;
88 extern int veriexec_strict;
89 /* this one requires sysctl.h to be included before verified_exec.h */
90 #ifdef VERIEXEC_NEED_NODE
91 extern struct sysctlnode *veriexec_count_node;
92 #endif /* VERIEXEC_NEED_NODE */
93
94 /*
95 * Operations vector for verified exec, this defines the characteristics
96 * for the fingerprint type.
97 */
98
99 /* Function types: init, update, final. */
100 typedef void (*VERIEXEC_INIT_FN)(void *);
101 typedef void (*VERIEXEC_UPDATE_FN)(void *, u_char *, u_int);
102 typedef void (*VERIEXEC_FINAL_FN)(u_char *, void *);
103
104 struct veriexec_fp_ops {
105 char type[VERIEXEC_TYPE_MAXLEN];
106 size_t hash_len;
107 size_t context_size;
108 VERIEXEC_INIT_FN init;
109 VERIEXEC_UPDATE_FN update;
110 VERIEXEC_FINAL_FN final;
111 LIST_ENTRY(veriexec_fp_ops) entries;
112 };
113
114 /*
115 * list structure definitions - needed in kern_exec.c
116 */
117
118 /* An entry in the per-device hash table. */
119 struct veriexec_hash_entry {
120 ino_t inode; /* Inode number. */
121 unsigned char type; /* Entry type. */
122 unsigned char *fp; /* Fingerprint. */
123 struct veriexec_fp_ops *ops; /* Fingerprint ops vector*/
124 LIST_ENTRY(veriexec_hash_entry) entries; /* List pointer. */
125 };
126
127 LIST_HEAD(veriexec_hashhead, veriexec_hash_entry) *hash_tbl;
128
129 /* Veriexec hash table information. */
130 struct veriexec_hashtbl {
131 struct veriexec_hashhead *hash_tbl;
132 size_t hash_size; /* Number of slots in the table. */
133 dev_t hash_dev; /* Device ID the hash table refers to. */
134 uint64_t hash_count; /* # of fingerprinted files in table. */
135 LIST_ENTRY(veriexec_hashtbl) hash_list;
136 };
137
138 /* Global list of hash tables. */
139 LIST_HEAD(, veriexec_hashtbl) veriexec_tables;
140
141 /* Mask to ensure bounded access to elements in the hash table. */
142 #define VERIEXEC_HASH_MASK(tbl) ((tbl)->hash_size - 1)
143
144 /* Readable values for veriexec_report(). */
145 #define REPORT_NOVERBOSE 0
146 #define REPORT_VERBOSE 1
147 #define REPORT_NOPANIC 0
148 #define REPORT_PANIC 1
149 #define REPORT_NOALARM 0
150 #define REPORT_ALARM 1
151
152 /*
153 * Hashing function: Takes an inode number modulus the mask to give back
154 * an index into the hash table.
155 */
156 #define VERIEXEC_HASH(tbl, inode) \
157 (hash32_buf(&(inode), sizeof((inode)), HASH32_BUF_INIT) \
158 & VERIEXEC_HASH_MASK(tbl))
159
160 void veriexec_init_fp_ops(void);
161 struct veriexec_fp_ops *veriexec_find_ops(u_char *name);
162 int veriexec_fp_calc(struct proc *, struct vnode *,
163 struct veriexec_hash_entry *, uint64_t, u_char *);
164 int veriexec_fp_cmp(struct veriexec_hash_entry *, u_char *);
165
166 struct veriexec_hashtbl *veriexec_tblfind(dev_t);
167 struct veriexec_hash_entry *veriexec_lookup(dev_t, ino_t);
168 int veriexec_hashadd(struct veriexec_hashtbl *, struct veriexec_hash_entry *);
169
170 int veriexec_verify(struct proc *, struct vnode *, struct vattr *,
171 const u_char *, int);
172 int veriexec_removechk(struct proc *, struct vnode *, const char *);
173 void veriexec_init_fp_ops(void);
174 void veriexec_report(const u_char *, const u_char *, struct vattr *,
175 struct proc *, int, int, int);
176
177 #endif
178
179 #ifdef VERIFIED_EXEC_DEBUG
180 #define veriexec_dprintf(x) printf x
181 #else
182 #define veriexec_dprintf(x)
183 #endif /* VERIFIED_EXEC_DEBUG */
184
185 #endif
186