summaryrefslogtreecommitdiff
path: root/security/apparmor/audit.c
blob: 6933cb2f679b0b816be5151a550a3d668ae1dd65 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
// SPDX-License-Identifier: GPL-2.0-only
/*
 * AppArmor security module
 *
 * This file contains AppArmor auditing functions
 *
 * Copyright (C) 1998-2008 Novell/SUSE
 * Copyright 2009-2010 Canonical Ltd.
 */

#include <linux/audit.h>
#include <linux/socket.h>

#include "include/apparmor.h"
#include "include/audit.h"
#include "include/policy.h"
#include "include/policy_ns.h"
#include "include/secid.h"

const char *const audit_mode_names[] = {
	"normal",
	"quiet_denied",
	"quiet",
	"noquiet",
	"all"
};

static const char *const aa_audit_type[] = {
	"AUDIT",
	"ALLOWED",
	"DENIED",
	"HINT",
	"STATUS",
	"ERROR",
	"KILLED",
	"AUTO"
};

static const char *const aa_class_names[] = {
	"none",
	"unknown",
	"file",
	"cap",
	"net",
	"rlimits",
	"domain",
	"mount",
	"unknown",
	"ptrace",
	"signal",
	"xmatch",
	"unknown",
	"unknown",
	"net",
	"unknown",
	"label",
	"posix_mqueue",
	"io_uring",
	"module",
	"lsm",
	"unknown",
	"unknown",
	"unknown",
	"unknown",
	"unknown",
	"unknown",
	"unknown",
	"unknown",
	"unknown",
	"unknown",
	"X",
	"dbus",
};


/*
 * Currently AppArmor auditing is fed straight into the audit framework.
 *
 * TODO:
 * netlink interface for complain mode
 * user auditing, - send user auditing to netlink interface
 * system control of whether user audit messages go to system log
 */

/**
 * audit_pre() - core AppArmor function.
 * @ab: audit buffer to fill (NOT NULL)
 * @va: audit structure containing data to audit (NOT NULL)
 *
 * Record common AppArmor audit data from @va
 */
static void audit_pre(struct audit_buffer *ab, void *va)
{
	struct apparmor_audit_data *ad = aad_of_va(va);

	if (aa_g_audit_header) {
		audit_log_format(ab, "apparmor=\"%s\"",
				 aa_audit_type[ad->type]);
	}

	if (ad->op)
		audit_log_format(ab, " operation=\"%s\"", ad->op);

	if (ad->class)
		audit_log_format(ab, " class=\"%s\"",
				 ad->class <= AA_CLASS_LAST ?
				 aa_class_names[ad->class] :
				 "unknown");

	if (ad->info) {
		audit_log_format(ab, " info=\"%s\"", ad->info);
		if (ad->error)
			audit_log_format(ab, " error=%d", ad->error);
	}

	if (ad->subj_label) {
		struct aa_label *label = ad->subj_label;

		if (label_isprofile(label)) {
			struct aa_profile *profile = labels_profile(label);

			if (profile->ns != root_ns) {
				audit_log_format(ab, " namespace=");
				audit_log_untrustedstring(ab,
						       profile->ns->base.hname);
			}
			audit_log_format(ab, " profile=");
			audit_log_untrustedstring(ab, profile->base.hname);
		} else {
			audit_log_format(ab, " label=");
			aa_label_xaudit(ab, root_ns, label, FLAG_VIEW_SUBNS,
					GFP_ATOMIC);
		}
	}

	if (ad->name) {
		audit_log_format(ab, " name=");
		audit_log_untrustedstring(ab, ad->name);
	}
}

/**
 * aa_audit_msg - Log a message to the audit subsystem
 * @type: audit type for the message
 * @ad: audit event structure (NOT NULL)
 * @cb: optional callback fn for type specific fields (MAYBE NULL)
 */
void aa_audit_msg(int type, struct apparmor_audit_data *ad,
		  void (*cb) (struct audit_buffer *, void *))
{
	ad->type = type;
	common_lsm_audit(&ad->common, audit_pre, cb);
}

/**
 * aa_audit - Log a profile based audit event to the audit subsystem
 * @type: audit type for the message
 * @profile: profile to check against (NOT NULL)
 * @ad: audit event (NOT NULL)
 * @cb: optional callback fn for type specific fields (MAYBE NULL)
 *
 * Handle default message switching based off of audit mode flags
 *
 * Returns: error on failure
 */
int aa_audit(int type, struct aa_profile *profile,
	     struct apparmor_audit_data *ad,
	     void (*cb) (struct audit_buffer *, void *))
{
	AA_BUG(!profile);

	if (type == AUDIT_APPARMOR_AUTO) {
		if (likely(!ad->error)) {
			if (AUDIT_MODE(profile) != AUDIT_ALL)
				return 0;
			type = AUDIT_APPARMOR_AUDIT;
		} else if (COMPLAIN_MODE(profile))
			type = AUDIT_APPARMOR_ALLOWED;
		else
			type = AUDIT_APPARMOR_DENIED;
	}
	if (AUDIT_MODE(profile) == AUDIT_QUIET ||
	    (type == AUDIT_APPARMOR_DENIED &&
	     AUDIT_MODE(profile) == AUDIT_QUIET_DENIED))
		return ad->error;

	if (KILL_MODE(profile) && type == AUDIT_APPARMOR_DENIED)
		type = AUDIT_APPARMOR_KILL;

	ad->subj_label = &profile->label;

	aa_audit_msg(type, ad, cb);

	if (ad->type == AUDIT_APPARMOR_KILL)
		(void)send_sig_info(SIGKILL, NULL,
			ad->common.type == LSM_AUDIT_DATA_TASK &&
			ad->common.u.tsk ? ad->common.u.tsk : current);

	if (ad->type == AUDIT_APPARMOR_ALLOWED)
		return complain_error(ad->error);

	return ad->error;
}

struct aa_audit_rule {
	struct aa_label *label;
};

void aa_audit_rule_free(void *vrule)
{
	struct aa_audit_rule *rule = vrule;

	if (rule) {
		if (!IS_ERR(rule->label))
			aa_put_label(rule->label);
		kfree(rule);
	}
}

int aa_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
{
	struct aa_audit_rule *rule;

	switch (field) {
	case AUDIT_SUBJ_ROLE:
		if (op != Audit_equal && op != Audit_not_equal)
			return -EINVAL;
		break;
	default:
		return -EINVAL;
	}

	rule = kzalloc(sizeof(struct aa_audit_rule), GFP_KERNEL);

	if (!rule)
		return -ENOMEM;

	/* Currently rules are treated as coming from the root ns */
	rule->label = aa_label_parse(&root_ns->unconfined->label, rulestr,
				     GFP_KERNEL, true, false);
	if (IS_ERR(rule->label)) {
		int err = PTR_ERR(rule->label);
		aa_audit_rule_free(rule);
		return err;
	}

	*vrule = rule;
	return 0;
}

int aa_audit_rule_known(struct audit_krule *rule)
{
	int i;

	for (i = 0; i < rule->field_count; i++) {
		struct audit_field *f = &rule->fields[i];

		switch (f->type) {
		case AUDIT_SUBJ_ROLE:
			return 1;
		}
	}

	return 0;
}

int aa_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule)
{
	struct aa_audit_rule *rule = vrule;
	struct aa_label *label;
	int found = 0;

	label = aa_secid_to_label(sid);

	if (!label)
		return -ENOENT;

	if (aa_label_is_subset(label, rule->label))
		found = 1;

	switch (field) {
	case AUDIT_SUBJ_ROLE:
		switch (op) {
		case Audit_equal:
			return found;
		case Audit_not_equal:
			return !found;
		}
	}
	return 0;
}