2 * Copyright (C) 2005,2006,2007,2008 IBM Corporation
5 * Kylene Hall <kjhall@us.ibm.com>
6 * Reiner Sailer <sailer@us.ibm.com>
7 * Mimi Zohar <zohar@us.ibm.com>
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation, version 2 of the
15 * implemenents security file system for reporting
16 * current measurement list and IMA statistics
18 #include <linux/fcntl.h>
19 #include <linux/slab.h>
20 #include <linux/module.h>
21 #include <linux/seq_file.h>
22 #include <linux/rculist.h>
23 #include <linux/rcupdate.h>
24 #include <linux/parser.h>
28 static int valid_policy
= 1;
30 static ssize_t
ima_show_htable_value(char __user
*buf
, size_t count
,
31 loff_t
*ppos
, atomic_long_t
*val
)
33 char tmpbuf
[TMPBUFLEN
];
36 len
= scnprintf(tmpbuf
, TMPBUFLEN
, "%li\n", atomic_long_read(val
));
37 return simple_read_from_buffer(buf
, count
, ppos
, tmpbuf
, len
);
40 static ssize_t
ima_show_htable_violations(struct file
*filp
,
42 size_t count
, loff_t
*ppos
)
44 return ima_show_htable_value(buf
, count
, ppos
, &ima_htable
.violations
);
47 static const struct file_operations ima_htable_violations_ops
= {
48 .read
= ima_show_htable_violations
51 static ssize_t
ima_show_measurements_count(struct file
*filp
,
53 size_t count
, loff_t
*ppos
)
55 return ima_show_htable_value(buf
, count
, ppos
, &ima_htable
.len
);
59 static const struct file_operations ima_measurements_count_ops
= {
60 .read
= ima_show_measurements_count
63 /* returns pointer to hlist_node */
64 static void *ima_measurements_start(struct seq_file
*m
, loff_t
*pos
)
67 struct ima_queue_entry
*qe
;
69 /* we need a lock since pos could point beyond last element */
71 list_for_each_entry_rcu(qe
, &ima_measurements
, later
) {
81 static void *ima_measurements_next(struct seq_file
*m
, void *v
, loff_t
*pos
)
83 struct ima_queue_entry
*qe
= v
;
85 /* lock protects when reading beyond last element
86 * against concurrent list-extension
89 qe
= list_entry_rcu(qe
->later
.next
,
90 struct ima_queue_entry
, later
);
94 return (&qe
->later
== &ima_measurements
) ? NULL
: qe
;
97 static void ima_measurements_stop(struct seq_file
*m
, void *v
)
101 static void ima_putc(struct seq_file
*m
, void *data
, int datalen
)
104 seq_putc(m
, *(char *)data
++);
109 * char[20]=template digest
110 * 32bit-le=template name size
111 * char[n]=template name
112 * eventdata[n]=template specific data
114 static int ima_measurements_show(struct seq_file
*m
, void *v
)
116 /* the list never shrinks, so we don't need a lock here */
117 struct ima_queue_entry
*qe
= v
;
118 struct ima_template_entry
*e
;
120 u32 pcr
= CONFIG_IMA_MEASURE_PCR_IDX
;
129 * PCR used is always the same (config option) in
130 * little-endian format
132 ima_putc(m
, &pcr
, sizeof pcr
);
134 /* 2nd: template digest */
135 ima_putc(m
, e
->digest
, IMA_DIGEST_SIZE
);
137 /* 3rd: template name size */
138 namelen
= strlen(e
->template_name
);
139 ima_putc(m
, &namelen
, sizeof namelen
);
141 /* 4th: template name */
142 ima_putc(m
, (void *)e
->template_name
, namelen
);
144 /* 5th: template specific data */
145 ima_template_show(m
, (struct ima_template_data
*)&e
->template,
150 static const struct seq_operations ima_measurments_seqops
= {
151 .start
= ima_measurements_start
,
152 .next
= ima_measurements_next
,
153 .stop
= ima_measurements_stop
,
154 .show
= ima_measurements_show
157 static int ima_measurements_open(struct inode
*inode
, struct file
*file
)
159 return seq_open(file
, &ima_measurments_seqops
);
162 static const struct file_operations ima_measurements_ops
= {
163 .open
= ima_measurements_open
,
166 .release
= seq_release
,
169 static void ima_print_digest(struct seq_file
*m
, u8
*digest
)
173 for (i
= 0; i
< IMA_DIGEST_SIZE
; i
++)
174 seq_printf(m
, "%02x", *(digest
+ i
));
177 void ima_template_show(struct seq_file
*m
, void *e
, enum ima_show_type show
)
179 struct ima_template_data
*entry
= e
;
184 ima_print_digest(m
, entry
->digest
);
185 seq_printf(m
, " %s\n", entry
->file_name
);
187 case IMA_SHOW_BINARY
:
188 ima_putc(m
, entry
->digest
, IMA_DIGEST_SIZE
);
190 namelen
= strlen(entry
->file_name
);
191 ima_putc(m
, &namelen
, sizeof namelen
);
192 ima_putc(m
, entry
->file_name
, namelen
);
199 static int ima_ascii_measurements_show(struct seq_file
*m
, void *v
)
201 /* the list never shrinks, so we don't need a lock here */
202 struct ima_queue_entry
*qe
= v
;
203 struct ima_template_entry
*e
;
210 /* 1st: PCR used (config option) */
211 seq_printf(m
, "%2d ", CONFIG_IMA_MEASURE_PCR_IDX
);
213 /* 2nd: SHA1 template hash */
214 ima_print_digest(m
, e
->digest
);
216 /* 3th: template name */
217 seq_printf(m
, " %s ", e
->template_name
);
219 /* 4th: template specific data */
220 ima_template_show(m
, (struct ima_template_data
*)&e
->template,
225 static const struct seq_operations ima_ascii_measurements_seqops
= {
226 .start
= ima_measurements_start
,
227 .next
= ima_measurements_next
,
228 .stop
= ima_measurements_stop
,
229 .show
= ima_ascii_measurements_show
232 static int ima_ascii_measurements_open(struct inode
*inode
, struct file
*file
)
234 return seq_open(file
, &ima_ascii_measurements_seqops
);
237 static const struct file_operations ima_ascii_measurements_ops
= {
238 .open
= ima_ascii_measurements_open
,
241 .release
= seq_release
,
244 static ssize_t
ima_write_policy(struct file
*file
, const char __user
*buf
,
245 size_t datalen
, loff_t
*ppos
)
250 if (datalen
>= PAGE_SIZE
)
253 /* No partial writes. */
256 data
= kmalloc(datalen
+ 1, GFP_KERNEL
);
260 if (copy_from_user(data
, buf
, datalen
)) {
264 *(data
+ datalen
) = '\0';
265 rc
= ima_parse_add_rule(data
);
275 static struct dentry
*ima_dir
;
276 static struct dentry
*binary_runtime_measurements
;
277 static struct dentry
*ascii_runtime_measurements
;
278 static struct dentry
*runtime_measurements_count
;
279 static struct dentry
*violations
;
280 static struct dentry
*ima_policy
;
282 static atomic_t policy_opencount
= ATOMIC_INIT(1);
284 * ima_open_policy: sequentialize access to the policy file
286 int ima_open_policy(struct inode
* inode
, struct file
* filp
)
288 /* No point in being allowed to open it if you aren't going to write */
289 if (!(filp
->f_flags
& O_WRONLY
))
291 if (atomic_dec_and_test(&policy_opencount
))
297 * ima_release_policy - start using the new measure policy rules.
299 * Initially, ima_measure points to the default policy rules, now
300 * point to the new policy rules, and remove the securityfs policy file,
301 * assuming a valid policy.
303 static int ima_release_policy(struct inode
*inode
, struct file
*file
)
308 atomic_set(&policy_opencount
, 1);
312 securityfs_remove(ima_policy
);
317 static const struct file_operations ima_measure_policy_ops
= {
318 .open
= ima_open_policy
,
319 .write
= ima_write_policy
,
320 .release
= ima_release_policy
323 int __init
ima_fs_init(void)
325 ima_dir
= securityfs_create_dir("ima", NULL
);
329 binary_runtime_measurements
=
330 securityfs_create_file("binary_runtime_measurements",
331 S_IRUSR
| S_IRGRP
, ima_dir
, NULL
,
332 &ima_measurements_ops
);
333 if (IS_ERR(binary_runtime_measurements
))
336 ascii_runtime_measurements
=
337 securityfs_create_file("ascii_runtime_measurements",
338 S_IRUSR
| S_IRGRP
, ima_dir
, NULL
,
339 &ima_ascii_measurements_ops
);
340 if (IS_ERR(ascii_runtime_measurements
))
343 runtime_measurements_count
=
344 securityfs_create_file("runtime_measurements_count",
345 S_IRUSR
| S_IRGRP
, ima_dir
, NULL
,
346 &ima_measurements_count_ops
);
347 if (IS_ERR(runtime_measurements_count
))
351 securityfs_create_file("violations", S_IRUSR
| S_IRGRP
,
352 ima_dir
, NULL
, &ima_htable_violations_ops
);
353 if (IS_ERR(violations
))
356 ima_policy
= securityfs_create_file("policy",
359 &ima_measure_policy_ops
);
360 if (IS_ERR(ima_policy
))
365 securityfs_remove(runtime_measurements_count
);
366 securityfs_remove(ascii_runtime_measurements
);
367 securityfs_remove(binary_runtime_measurements
);
368 securityfs_remove(ima_dir
);
369 securityfs_remove(ima_policy
);
373 void __exit
ima_fs_cleanup(void)
375 securityfs_remove(violations
);
376 securityfs_remove(runtime_measurements_count
);
377 securityfs_remove(ascii_runtime_measurements
);
378 securityfs_remove(binary_runtime_measurements
);
379 securityfs_remove(ima_dir
);
380 securityfs_remove(ima_policy
);