1 /*
2 * Copyright (C) 2005,2006,2007,2008 IBM Corporation
3 *
4 * Authors:
5 * Reiner Sailer <sailer@watson.ibm.com>
6 * Mimi Zohar <zohar@us.ibm.com>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation, version 2 of the
11 * License.
12 *
13 * File: ima.h
14 * internal Integrity Measurement Architecture (IMA) definitions
15 */
16
17 #ifndef __LINUX_IMA_H
18 #define __LINUX_IMA_H
19
20 #include <linux/types.h>
21 #include <linux/crypto.h>
22 #include <linux/security.h>
23 #include <linux/hash.h>
24 #include <linux/tpm.h>
25 #include <linux/audit.h>
26
27 enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_ASCII };
28 enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
29
30 /* digest size for IMA, fits SHA1 or MD5 */
31 #define IMA_DIGEST_SIZE 20
32 #define IMA_EVENT_NAME_LEN_MAX 255
33
34 #define IMA_HASH_BITS 9
35 #define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS)
36
37 /* set during initialization */
38 extern int iint_initialized;
39 extern int ima_initialized;
40 extern int ima_used_chip;
41 extern char *ima_hash;
42
43 /* IMA inode template definition */
44 struct ima_template_data {
45 u8 digest[IMA_DIGEST_SIZE]; /* sha1/md5 measurement hash */
46 char file_name[IMA_EVENT_NAME_LEN_MAX + 1]; /* name + \0 */
47 };
48
49 struct ima_template_entry {
50 u8 digest[IMA_DIGEST_SIZE]; /* sha1 or md5 measurement hash */
51 const char *template_name;
52 int template_len;
53 struct ima_template_data template;
54 };
55
56 struct ima_queue_entry {
57 struct hlist_node hnext; /* place in hash collision list */
58 struct list_head later; /* place in ima_measurements list */
59 struct ima_template_entry *entry;
60 };
61 extern struct list_head ima_measurements; /* list of all measurements */
62
63 /* declarations */
64 void integrity_audit_msg(int audit_msgno, struct inode *inode,
65 const unsigned char *fname, const char *op,
66 const char *cause, int result, int info);
67
68 /* Internal IMA function definitions */
69 int ima_init(void);
70 void ima_cleanup(void);
71 int ima_fs_init(void);
72 void ima_fs_cleanup(void);
73 int ima_inode_alloc(struct inode *inode);
74 int ima_add_template_entry(struct ima_template_entry *entry, int violation,
75 const char *op, struct inode *inode);
76 int ima_calc_hash(struct file *file, char *digest);
77 int ima_calc_template_hash(int template_len, void *template, char *digest);
78 int ima_calc_boot_aggregate(char *digest);
79 void ima_add_violation(struct inode *inode, const unsigned char *filename,
80 const char *op, const char *cause);
81
82 /*
83 * used to protect h_table and sha_table
84 */
85 extern spinlock_t ima_queue_lock;
86
87 struct ima_h_table {
88 atomic_long_t len; /* number of stored measurements in the list */
89 atomic_long_t violations;
90 struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE];
91 };
92 extern struct ima_h_table ima_htable;
93
ima_hash_key(u8 * digest)94 static inline unsigned long ima_hash_key(u8 *digest)
95 {
96 return hash_long(*digest, IMA_HASH_BITS);
97 }
98
99 /* iint cache flags */
100 #define IMA_MEASURED 0x01
101
102 /* integrity data associated with an inode */
103 struct ima_iint_cache {
104 struct rb_node rb_node; /* rooted in ima_iint_tree */
105 struct inode *inode; /* back pointer to inode in question */
106 u64 version; /* track inode changes */
107 unsigned char flags;
108 u8 digest[IMA_DIGEST_SIZE];
109 struct mutex mutex; /* protects: version, flags, digest */
110 };
111
112 /* LIM API function definitions */
113 int ima_must_measure(struct inode *inode, int mask, int function);
114 int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file);
115 void ima_store_measurement(struct ima_iint_cache *iint, struct file *file,
116 const unsigned char *filename);
117 int ima_store_template(struct ima_template_entry *entry, int violation,
118 struct inode *inode);
119 void ima_template_show(struct seq_file *m, void *e,
120 enum ima_show_type show);
121
122 /* rbtree tree calls to lookup, insert, delete
123 * integrity data associated with an inode.
124 */
125 struct ima_iint_cache *ima_iint_insert(struct inode *inode);
126 struct ima_iint_cache *ima_iint_find(struct inode *inode);
127
128 /* IMA policy related functions */
129 enum ima_hooks { FILE_CHECK = 1, FILE_MMAP, BPRM_CHECK };
130
131 int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask);
132 void ima_init_policy(void);
133 void ima_update_policy(void);
134 ssize_t ima_parse_add_rule(char *);
135 void ima_delete_rules(void);
136
137 /* LSM based policy rules require audit */
138 #ifdef CONFIG_IMA_LSM_RULES
139
140 #define security_filter_rule_init security_audit_rule_init
141 #define security_filter_rule_match security_audit_rule_match
142
143 #else
144
security_filter_rule_init(u32 field,u32 op,char * rulestr,void ** lsmrule)145 static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr,
146 void **lsmrule)
147 {
148 return -EINVAL;
149 }
150
security_filter_rule_match(u32 secid,u32 field,u32 op,void * lsmrule,struct audit_context * actx)151 static inline int security_filter_rule_match(u32 secid, u32 field, u32 op,
152 void *lsmrule,
153 struct audit_context *actx)
154 {
155 return -EINVAL;
156 }
157 #endif /* CONFIG_IMA_LSM_RULES */
158 #endif
159