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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AppArmor security module
4 *
5 * This file contains AppArmor ipc mediation
6 *
7 * Copyright (C) 1998-2008 Novell/SUSE
8 * Copyright 2009-2017 Canonical Ltd.
9 */
10
11#include <linux/gfp.h>
12#include <linux/ptrace.h>
13
14#include "include/audit.h"
15#include "include/capability.h"
16#include "include/cred.h"
17#include "include/policy.h"
18#include "include/ipc.h"
19#include "include/sig_names.h"
20
21/**
22 * audit_ptrace_mask - convert mask to permission string
23 * @buffer: buffer to write string to (NOT NULL)
24 * @mask: permission mask to convert
25 */
26static void audit_ptrace_mask(struct audit_buffer *ab, u32 mask)
27{
28 switch (mask) {
29 case MAY_READ:
30 audit_log_string(ab, "read");
31 break;
32 case MAY_WRITE:
33 audit_log_string(ab, "trace");
34 break;
35 case AA_MAY_BE_READ:
36 audit_log_string(ab, "readby");
37 break;
38 case AA_MAY_BE_TRACED:
39 audit_log_string(ab, "tracedby");
40 break;
41 }
42}
43
44/* call back to audit ptrace fields */
45static void audit_ptrace_cb(struct audit_buffer *ab, void *va)
46{
47 struct common_audit_data *sa = va;
48
49 if (aad(sa)->request & AA_PTRACE_PERM_MASK) {
50 audit_log_format(ab, " requested_mask=");
51 audit_ptrace_mask(ab, aad(sa)->request);
52
53 if (aad(sa)->denied & AA_PTRACE_PERM_MASK) {
54 audit_log_format(ab, " denied_mask=");
55 audit_ptrace_mask(ab, aad(sa)->denied);
56 }
57 }
58 audit_log_format(ab, " peer=");
59 aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,
60 FLAGS_NONE, GFP_ATOMIC);
61}
62
63/* assumes check for PROFILE_MEDIATES is already done */
64/* TODO: conditionals */
65static int profile_ptrace_perm(struct aa_profile *profile,
66 struct aa_label *peer, u32 request,
67 struct common_audit_data *sa)
68{
69 struct aa_perms perms = { };
70
71 aad(sa)->peer = peer;
72 aa_profile_match_label(profile, peer, AA_CLASS_PTRACE, request,
73 &perms);
74 aa_apply_modes_to_perms(profile, &perms);
75 return aa_check_perms(profile, &perms, request, sa, audit_ptrace_cb);
76}
77
78static int profile_tracee_perm(struct aa_profile *tracee,
79 struct aa_label *tracer, u32 request,
80 struct common_audit_data *sa)
81{
82 if (profile_unconfined(tracee) || unconfined(tracer) ||
83 !PROFILE_MEDIATES(tracee, AA_CLASS_PTRACE))
84 return 0;
85
86 return profile_ptrace_perm(tracee, tracer, request, sa);
87}
88
89static int profile_tracer_perm(struct aa_profile *tracer,
90 struct aa_label *tracee, u32 request,
91 struct common_audit_data *sa)
92{
93 if (profile_unconfined(tracer))
94 return 0;
95
96 if (PROFILE_MEDIATES(tracer, AA_CLASS_PTRACE))
97 return profile_ptrace_perm(tracer, tracee, request, sa);
98
99 /* profile uses the old style capability check for ptrace */
100 if (&tracer->label == tracee)
101 return 0;
102
103 aad(sa)->label = &tracer->label;
104 aad(sa)->peer = tracee;
105 aad(sa)->request = 0;
106 aad(sa)->error = aa_capable(&tracer->label, CAP_SYS_PTRACE,
107 CAP_OPT_NONE);
108
109 return aa_audit(AUDIT_APPARMOR_AUTO, tracer, sa, audit_ptrace_cb);
110}
111
112/**
113 * aa_may_ptrace - test if tracer task can trace the tracee
114 * @tracer: label of the task doing the tracing (NOT NULL)
115 * @tracee: task label to be traced
116 * @request: permission request
117 *
118 * Returns: %0 else error code if permission denied or error
119 */
120int aa_may_ptrace(struct aa_label *tracer, struct aa_label *tracee,
121 u32 request)
122{
123 struct aa_profile *profile;
124 u32 xrequest = request << PTRACE_PERM_SHIFT;
125 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_PTRACE);
126
127 return xcheck_labels(tracer, tracee, profile,
128 profile_tracer_perm(profile, tracee, request, &sa),
129 profile_tracee_perm(profile, tracer, xrequest, &sa));
130}
131
132
133static inline int map_signal_num(int sig)
134{
135 if (sig > SIGRTMAX)
136 return SIGUNKNOWN;
137 else if (sig >= SIGRTMIN)
138 return sig - SIGRTMIN + SIGRT_BASE;
139 else if (sig < MAXMAPPED_SIG)
140 return sig_map[sig];
141 return SIGUNKNOWN;
142}
143
144/**
145 * audit_file_mask - convert mask to permission string
146 * @buffer: buffer to write string to (NOT NULL)
147 * @mask: permission mask to convert
148 */
149static void audit_signal_mask(struct audit_buffer *ab, u32 mask)
150{
151 if (mask & MAY_READ)
152 audit_log_string(ab, "receive");
153 if (mask & MAY_WRITE)
154 audit_log_string(ab, "send");
155}
156
157/**
158 * audit_cb - call back for signal specific audit fields
159 * @ab: audit_buffer (NOT NULL)
160 * @va: audit struct to audit values of (NOT NULL)
161 */
162static void audit_signal_cb(struct audit_buffer *ab, void *va)
163{
164 struct common_audit_data *sa = va;
165
166 if (aad(sa)->request & AA_SIGNAL_PERM_MASK) {
167 audit_log_format(ab, " requested_mask=");
168 audit_signal_mask(ab, aad(sa)->request);
169 if (aad(sa)->denied & AA_SIGNAL_PERM_MASK) {
170 audit_log_format(ab, " denied_mask=");
171 audit_signal_mask(ab, aad(sa)->denied);
172 }
173 }
174 if (aad(sa)->signal == SIGUNKNOWN)
175 audit_log_format(ab, "signal=unknown(%d)",
176 aad(sa)->unmappedsig);
177 else if (aad(sa)->signal < MAXMAPPED_SIGNAME)
178 audit_log_format(ab, " signal=%s", sig_names[aad(sa)->signal]);
179 else
180 audit_log_format(ab, " signal=rtmin+%d",
181 aad(sa)->signal - SIGRT_BASE);
182 audit_log_format(ab, " peer=");
183 aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,
184 FLAGS_NONE, GFP_ATOMIC);
185}
186
187static int profile_signal_perm(struct aa_profile *profile,
188 struct aa_label *peer, u32 request,
189 struct common_audit_data *sa)
190{
191 struct aa_perms perms;
192 unsigned int state;
193
194 if (profile_unconfined(profile) ||
195 !PROFILE_MEDIATES(profile, AA_CLASS_SIGNAL))
196 return 0;
197
198 aad(sa)->peer = peer;
199 /* TODO: secondary cache check <profile, profile, perm> */
200 state = aa_dfa_next(profile->policy.dfa,
201 profile->policy.start[AA_CLASS_SIGNAL],
202 aad(sa)->signal);
203 aa_label_match(profile, peer, state, false, request, &perms);
204 aa_apply_modes_to_perms(profile, &perms);
205 return aa_check_perms(profile, &perms, request, sa, audit_signal_cb);
206}
207
208int aa_may_signal(struct aa_label *sender, struct aa_label *target, int sig)
209{
210 struct aa_profile *profile;
211 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SIGNAL);
212
213 aad(&sa)->signal = map_signal_num(sig);
214 aad(&sa)->unmappedsig = sig;
215 return xcheck_labels(sender, target, profile,
216 profile_signal_perm(profile, target, MAY_WRITE, &sa),
217 profile_signal_perm(profile, sender, MAY_READ, &sa));
218}
1/*
2 * AppArmor security module
3 *
4 * This file contains AppArmor ipc mediation
5 *
6 * Copyright (C) 1998-2008 Novell/SUSE
7 * Copyright 2009-2017 Canonical Ltd.
8 *
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
12 * License.
13 */
14
15#include <linux/gfp.h>
16#include <linux/ptrace.h>
17
18#include "include/audit.h"
19#include "include/capability.h"
20#include "include/cred.h"
21#include "include/policy.h"
22#include "include/ipc.h"
23#include "include/sig_names.h"
24
25/**
26 * audit_ptrace_mask - convert mask to permission string
27 * @buffer: buffer to write string to (NOT NULL)
28 * @mask: permission mask to convert
29 */
30static void audit_ptrace_mask(struct audit_buffer *ab, u32 mask)
31{
32 switch (mask) {
33 case MAY_READ:
34 audit_log_string(ab, "read");
35 break;
36 case MAY_WRITE:
37 audit_log_string(ab, "trace");
38 break;
39 case AA_MAY_BE_READ:
40 audit_log_string(ab, "readby");
41 break;
42 case AA_MAY_BE_TRACED:
43 audit_log_string(ab, "tracedby");
44 break;
45 }
46}
47
48/* call back to audit ptrace fields */
49static void audit_ptrace_cb(struct audit_buffer *ab, void *va)
50{
51 struct common_audit_data *sa = va;
52
53 if (aad(sa)->request & AA_PTRACE_PERM_MASK) {
54 audit_log_format(ab, " requested_mask=");
55 audit_ptrace_mask(ab, aad(sa)->request);
56
57 if (aad(sa)->denied & AA_PTRACE_PERM_MASK) {
58 audit_log_format(ab, " denied_mask=");
59 audit_ptrace_mask(ab, aad(sa)->denied);
60 }
61 }
62 audit_log_format(ab, " peer=");
63 aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,
64 FLAGS_NONE, GFP_ATOMIC);
65}
66
67/* assumes check for PROFILE_MEDIATES is already done */
68/* TODO: conditionals */
69static int profile_ptrace_perm(struct aa_profile *profile,
70 struct aa_label *peer, u32 request,
71 struct common_audit_data *sa)
72{
73 struct aa_perms perms = { };
74
75 aad(sa)->peer = peer;
76 aa_profile_match_label(profile, peer, AA_CLASS_PTRACE, request,
77 &perms);
78 aa_apply_modes_to_perms(profile, &perms);
79 return aa_check_perms(profile, &perms, request, sa, audit_ptrace_cb);
80}
81
82static int profile_tracee_perm(struct aa_profile *tracee,
83 struct aa_label *tracer, u32 request,
84 struct common_audit_data *sa)
85{
86 if (profile_unconfined(tracee) || unconfined(tracer) ||
87 !PROFILE_MEDIATES(tracee, AA_CLASS_PTRACE))
88 return 0;
89
90 return profile_ptrace_perm(tracee, tracer, request, sa);
91}
92
93static int profile_tracer_perm(struct aa_profile *tracer,
94 struct aa_label *tracee, u32 request,
95 struct common_audit_data *sa)
96{
97 if (profile_unconfined(tracer))
98 return 0;
99
100 if (PROFILE_MEDIATES(tracer, AA_CLASS_PTRACE))
101 return profile_ptrace_perm(tracer, tracee, request, sa);
102
103 /* profile uses the old style capability check for ptrace */
104 if (&tracer->label == tracee)
105 return 0;
106
107 aad(sa)->label = &tracer->label;
108 aad(sa)->peer = tracee;
109 aad(sa)->request = 0;
110 aad(sa)->error = aa_capable(&tracer->label, CAP_SYS_PTRACE, 1);
111
112 return aa_audit(AUDIT_APPARMOR_AUTO, tracer, sa, audit_ptrace_cb);
113}
114
115/**
116 * aa_may_ptrace - test if tracer task can trace the tracee
117 * @tracer: label of the task doing the tracing (NOT NULL)
118 * @tracee: task label to be traced
119 * @request: permission request
120 *
121 * Returns: %0 else error code if permission denied or error
122 */
123int aa_may_ptrace(struct aa_label *tracer, struct aa_label *tracee,
124 u32 request)
125{
126 struct aa_profile *profile;
127 u32 xrequest = request << PTRACE_PERM_SHIFT;
128 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_PTRACE);
129
130 return xcheck_labels(tracer, tracee, profile,
131 profile_tracer_perm(profile, tracee, request, &sa),
132 profile_tracee_perm(profile, tracer, xrequest, &sa));
133}
134
135
136static inline int map_signal_num(int sig)
137{
138 if (sig > SIGRTMAX)
139 return SIGUNKNOWN;
140 else if (sig >= SIGRTMIN)
141 return sig - SIGRTMIN + SIGRT_BASE;
142 else if (sig < MAXMAPPED_SIG)
143 return sig_map[sig];
144 return SIGUNKNOWN;
145}
146
147/**
148 * audit_file_mask - convert mask to permission string
149 * @buffer: buffer to write string to (NOT NULL)
150 * @mask: permission mask to convert
151 */
152static void audit_signal_mask(struct audit_buffer *ab, u32 mask)
153{
154 if (mask & MAY_READ)
155 audit_log_string(ab, "receive");
156 if (mask & MAY_WRITE)
157 audit_log_string(ab, "send");
158}
159
160/**
161 * audit_cb - call back for signal specific audit fields
162 * @ab: audit_buffer (NOT NULL)
163 * @va: audit struct to audit values of (NOT NULL)
164 */
165static void audit_signal_cb(struct audit_buffer *ab, void *va)
166{
167 struct common_audit_data *sa = va;
168
169 if (aad(sa)->request & AA_SIGNAL_PERM_MASK) {
170 audit_log_format(ab, " requested_mask=");
171 audit_signal_mask(ab, aad(sa)->request);
172 if (aad(sa)->denied & AA_SIGNAL_PERM_MASK) {
173 audit_log_format(ab, " denied_mask=");
174 audit_signal_mask(ab, aad(sa)->denied);
175 }
176 }
177 if (aad(sa)->signal == SIGUNKNOWN)
178 audit_log_format(ab, "signal=unknown(%d)",
179 aad(sa)->unmappedsig);
180 else if (aad(sa)->signal < MAXMAPPED_SIGNAME)
181 audit_log_format(ab, " signal=%s", sig_names[aad(sa)->signal]);
182 else
183 audit_log_format(ab, " signal=rtmin+%d",
184 aad(sa)->signal - SIGRT_BASE);
185 audit_log_format(ab, " peer=");
186 aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,
187 FLAGS_NONE, GFP_ATOMIC);
188}
189
190static int profile_signal_perm(struct aa_profile *profile,
191 struct aa_label *peer, u32 request,
192 struct common_audit_data *sa)
193{
194 struct aa_perms perms;
195 unsigned int state;
196
197 if (profile_unconfined(profile) ||
198 !PROFILE_MEDIATES(profile, AA_CLASS_SIGNAL))
199 return 0;
200
201 aad(sa)->peer = peer;
202 /* TODO: secondary cache check <profile, profile, perm> */
203 state = aa_dfa_next(profile->policy.dfa,
204 profile->policy.start[AA_CLASS_SIGNAL],
205 aad(sa)->signal);
206 aa_label_match(profile, peer, state, false, request, &perms);
207 aa_apply_modes_to_perms(profile, &perms);
208 return aa_check_perms(profile, &perms, request, sa, audit_signal_cb);
209}
210
211int aa_may_signal(struct aa_label *sender, struct aa_label *target, int sig)
212{
213 struct aa_profile *profile;
214 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SIGNAL);
215
216 aad(&sa)->signal = map_signal_num(sig);
217 aad(&sa)->unmappedsig = sig;
218 return xcheck_labels(sender, target, profile,
219 profile_signal_perm(profile, target, MAY_WRITE, &sa),
220 profile_signal_perm(profile, sender, MAY_READ, &sa));
221}