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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#include "../integrity.h"
28
29enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
30		     IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
31enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
32
33/* digest size for IMA, fits SHA1 or MD5 */
34#define IMA_DIGEST_SIZE		SHA1_DIGEST_SIZE
35#define IMA_EVENT_NAME_LEN_MAX	255
36
37#define IMA_HASH_BITS 9
38#define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS)
39
40#define IMA_TEMPLATE_FIELD_ID_MAX_LEN	16
41#define IMA_TEMPLATE_NUM_FIELDS_MAX	15
42
43#define IMA_TEMPLATE_IMA_NAME "ima"
44#define IMA_TEMPLATE_IMA_FMT "d|n"
45
46/* current content of the policy */
47extern int ima_policy_flag;
48
49/* set during initialization */
50extern int ima_initialized;
51extern int ima_used_chip;
52extern int ima_hash_algo;
53extern int ima_appraise;
54
55/* IMA template field data definition */
56struct ima_field_data {
57	u8 *data;
58	u32 len;
59};
60
61/* IMA template field definition */
62struct ima_template_field {
63	const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN];
64	int (*field_init) (struct integrity_iint_cache *iint, struct file *file,
65			   const unsigned char *filename,
66			   struct evm_ima_xattr_data *xattr_value,
67			   int xattr_len, struct ima_field_data *field_data);
68	void (*field_show) (struct seq_file *m, enum ima_show_type show,
69			    struct ima_field_data *field_data);
70};
71
72/* IMA template descriptor definition */
73struct ima_template_desc {
74	char *name;
75	char *fmt;
76	int num_fields;
77	struct ima_template_field **fields;
78};
79
80struct ima_template_entry {
81	u8 digest[TPM_DIGEST_SIZE];	/* sha1 or md5 measurement hash */
82	struct ima_template_desc *template_desc; /* template descriptor */
83	u32 template_data_len;
84	struct ima_field_data template_data[0];	/* template related data */
85};
86
87struct ima_queue_entry {
88	struct hlist_node hnext;	/* place in hash collision list */
89	struct list_head later;		/* place in ima_measurements list */
90	struct ima_template_entry *entry;
91};
92extern struct list_head ima_measurements;	/* list of all measurements */
93
94/* Internal IMA function definitions */
95int ima_init(void);
96int ima_fs_init(void);
97int ima_add_template_entry(struct ima_template_entry *entry, int violation,
98			   const char *op, struct inode *inode,
99			   const unsigned char *filename);
100int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash);
101int ima_calc_field_array_hash(struct ima_field_data *field_data,
102			      struct ima_template_desc *desc, int num_fields,
103			      struct ima_digest_data *hash);
104int __init ima_calc_boot_aggregate(struct ima_digest_data *hash);
105void ima_add_violation(struct file *file, const unsigned char *filename,
106		       const char *op, const char *cause);
107int ima_init_crypto(void);
108void ima_putc(struct seq_file *m, void *data, int datalen);
109void ima_print_digest(struct seq_file *m, u8 *digest, u32 size);
110struct ima_template_desc *ima_template_desc_current(void);
111int ima_init_template(void);
112
113/*
114 * used to protect h_table and sha_table
115 */
116extern spinlock_t ima_queue_lock;
117
118struct ima_h_table {
119	atomic_long_t len;	/* number of stored measurements in the list */
120	atomic_long_t violations;
121	struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE];
122};
123extern struct ima_h_table ima_htable;
124
125static inline unsigned long ima_hash_key(u8 *digest)
126{
127	return hash_long(*digest, IMA_HASH_BITS);
128}
129
130/* LIM API function definitions */
131int ima_get_action(struct inode *inode, int mask, int function);
132int ima_must_measure(struct inode *inode, int mask, int function);
133int ima_collect_measurement(struct integrity_iint_cache *iint,
134			    struct file *file,
135			    struct evm_ima_xattr_data **xattr_value,
136			    int *xattr_len);
137void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
138			   const unsigned char *filename,
139			   struct evm_ima_xattr_data *xattr_value,
140			   int xattr_len);
141void ima_audit_measurement(struct integrity_iint_cache *iint,
142			   const unsigned char *filename);
143int ima_alloc_init_template(struct integrity_iint_cache *iint,
144			    struct file *file, const unsigned char *filename,
145			    struct evm_ima_xattr_data *xattr_value,
146			    int xattr_len, struct ima_template_entry **entry);
147int ima_store_template(struct ima_template_entry *entry, int violation,
148		       struct inode *inode, const unsigned char *filename);
149void ima_free_template_entry(struct ima_template_entry *entry);
150const char *ima_d_path(struct path *path, char **pathbuf);
151
152/* IMA policy related functions */
153enum ima_hooks { FILE_CHECK = 1, MMAP_CHECK, BPRM_CHECK, MODULE_CHECK, FIRMWARE_CHECK, POST_SETATTR };
154
155int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask,
156		     int flags);
157void ima_init_policy(void);
158void ima_update_policy(void);
159void ima_update_policy_flag(void);
160ssize_t ima_parse_add_rule(char *);
161void ima_delete_rules(void);
162
163/* Appraise integrity measurements */
164#define IMA_APPRAISE_ENFORCE	0x01
165#define IMA_APPRAISE_FIX	0x02
166#define IMA_APPRAISE_LOG	0x04
167#define IMA_APPRAISE_MODULES	0x08
168#define IMA_APPRAISE_FIRMWARE	0x10
169
170#ifdef CONFIG_IMA_APPRAISE
171int ima_appraise_measurement(int func, struct integrity_iint_cache *iint,
172			     struct file *file, const unsigned char *filename,
173			     struct evm_ima_xattr_data *xattr_value,
174			     int xattr_len, int opened);
175int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func);
176void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file);
177enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
178					   int func);
179void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len,
180		       struct ima_digest_data *hash);
181int ima_read_xattr(struct dentry *dentry,
182		   struct evm_ima_xattr_data **xattr_value);
183
184#else
185static inline int ima_appraise_measurement(int func,
186					   struct integrity_iint_cache *iint,
187					   struct file *file,
188					   const unsigned char *filename,
189					   struct evm_ima_xattr_data *xattr_value,
190					   int xattr_len, int opened)
191{
192	return INTEGRITY_UNKNOWN;
193}
194
195static inline int ima_must_appraise(struct inode *inode, int mask,
196				    enum ima_hooks func)
197{
198	return 0;
199}
200
201static inline void ima_update_xattr(struct integrity_iint_cache *iint,
202				    struct file *file)
203{
204}
205
206static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache
207							 *iint, int func)
208{
209	return INTEGRITY_UNKNOWN;
210}
211
212static inline void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value,
213				     int xattr_len,
214				     struct ima_digest_data *hash)
215{
216}
217
218static inline int ima_read_xattr(struct dentry *dentry,
219				 struct evm_ima_xattr_data **xattr_value)
220{
221	return 0;
222}
223
224#endif
225
226/* LSM based policy rules require audit */
227#ifdef CONFIG_IMA_LSM_RULES
228
229#define security_filter_rule_init security_audit_rule_init
230#define security_filter_rule_match security_audit_rule_match
231
232#else
233
234static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr,
235					    void **lsmrule)
236{
237	return -EINVAL;
238}
239
240static inline int security_filter_rule_match(u32 secid, u32 field, u32 op,
241					     void *lsmrule,
242					     struct audit_context *actx)
243{
244	return -EINVAL;
245}
246#endif /* CONFIG_IMA_LSM_RULES */
247
248#ifdef CONFIG_IMA_TRUSTED_KEYRING
249static inline int ima_init_keyring(const unsigned int id)
250{
251	return integrity_init_keyring(id);
252}
253#else
254static inline int ima_init_keyring(const unsigned int id)
255{
256	return 0;
257}
258#endif /* CONFIG_IMA_TRUSTED_KEYRING */
259#endif
260