1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Creating audit records for mapped devices.
4 *
5 * Copyright (C) 2021 Fraunhofer AISEC. All rights reserved.
6 *
7 * Authors: Michael Weiß <michael.weiss@aisec.fraunhofer.de>
8 */
9
10 #include <linux/audit.h>
11 #include <linux/module.h>
12 #include <linux/device-mapper.h>
13 #include <linux/bio.h>
14 #include <linux/blkdev.h>
15
16 #include "dm-audit.h"
17 #include "dm-core.h"
18
dm_audit_log_start(int audit_type,const char * dm_msg_prefix,const char * op)19 static struct audit_buffer *dm_audit_log_start(int audit_type,
20 const char *dm_msg_prefix,
21 const char *op)
22 {
23 struct audit_buffer *ab;
24
25 if (audit_enabled == AUDIT_OFF)
26 return NULL;
27
28 ab = audit_log_start(audit_context(), GFP_KERNEL, audit_type);
29 if (unlikely(!ab))
30 return NULL;
31
32 audit_log_format(ab, "module=%s op=%s", dm_msg_prefix, op);
33 return ab;
34 }
35
dm_audit_log_ti(int audit_type,const char * dm_msg_prefix,const char * op,struct dm_target * ti,int result)36 void dm_audit_log_ti(int audit_type, const char *dm_msg_prefix, const char *op,
37 struct dm_target *ti, int result)
38 {
39 struct audit_buffer *ab = NULL;
40 struct mapped_device *md = dm_table_get_md(ti->table);
41 int dev_major = dm_disk(md)->major;
42 int dev_minor = dm_disk(md)->first_minor;
43
44 switch (audit_type) {
45 case AUDIT_DM_CTRL:
46 ab = dm_audit_log_start(audit_type, dm_msg_prefix, op);
47 if (unlikely(!ab))
48 return;
49 audit_log_task_info(ab);
50 audit_log_format(ab, " dev=%d:%d error_msg='%s'", dev_major,
51 dev_minor, !result ? ti->error : "success");
52 break;
53 case AUDIT_DM_EVENT:
54 ab = dm_audit_log_start(audit_type, dm_msg_prefix, op);
55 if (unlikely(!ab))
56 return;
57 audit_log_format(ab, " dev=%d:%d sector=?", dev_major,
58 dev_minor);
59 break;
60 default: /* unintended use */
61 return;
62 }
63
64 audit_log_format(ab, " res=%d", result);
65 audit_log_end(ab);
66 }
67 EXPORT_SYMBOL_GPL(dm_audit_log_ti);
68
dm_audit_log_bio(const char * dm_msg_prefix,const char * op,struct bio * bio,sector_t sector,int result)69 void dm_audit_log_bio(const char *dm_msg_prefix, const char *op,
70 struct bio *bio, sector_t sector, int result)
71 {
72 struct audit_buffer *ab;
73 int dev_major = MAJOR(bio->bi_bdev->bd_dev);
74 int dev_minor = MINOR(bio->bi_bdev->bd_dev);
75
76 ab = dm_audit_log_start(AUDIT_DM_EVENT, dm_msg_prefix, op);
77 if (unlikely(!ab))
78 return;
79
80 audit_log_format(ab, " dev=%d:%d sector=%llu res=%d",
81 dev_major, dev_minor, sector, result);
82 audit_log_end(ab);
83 }
84 EXPORT_SYMBOL_GPL(dm_audit_log_bio);
85