1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * AppArmor security module 4 * 5 * This file contains AppArmor auditing functions 6 * 7 * Copyright (C) 1998-2008 Novell/SUSE 8 * Copyright 2009-2010 Canonical Ltd. 9 */ 10 11 #include <linux/audit.h> 12 #include <linux/socket.h> 13 14 #include "include/apparmor.h" 15 #include "include/audit.h" 16 #include "include/policy.h" 17 #include "include/policy_ns.h" 18 #include "include/secid.h" 19 20 const char *const audit_mode_names[] = { 21 "normal", 22 "quiet_denied", 23 "quiet", 24 "noquiet", 25 "all" 26 }; 27 28 static const char *const aa_audit_type[] = { 29 "AUDIT", 30 "ALLOWED", 31 "DENIED", 32 "HINT", 33 "STATUS", 34 "ERROR", 35 "KILLED", 36 "AUTO" 37 }; 38 39 /* 40 * Currently AppArmor auditing is fed straight into the audit framework. 41 * 42 * TODO: 43 * netlink interface for complain mode 44 * user auditing, - send user auditing to netlink interface 45 * system control of whether user audit messages go to system log 46 */ 47 48 /** 49 * audit_base - core AppArmor function. 50 * @ab: audit buffer to fill (NOT NULL) 51 * @ca: audit structure containing data to audit (NOT NULL) 52 * 53 * Record common AppArmor audit data from @sa 54 */ 55 static void audit_pre(struct audit_buffer *ab, void *ca) 56 { 57 struct common_audit_data *sa = ca; 58 59 if (aa_g_audit_header) { 60 audit_log_format(ab, "apparmor=\"%s\"", 61 aa_audit_type[aad(sa)->type]); 62 } 63 64 if (aad(sa)->op) { 65 audit_log_format(ab, " operation=\"%s\"", aad(sa)->op); 66 } 67 68 if (aad(sa)->info) { 69 audit_log_format(ab, " info=\"%s\"", aad(sa)->info); 70 if (aad(sa)->error) 71 audit_log_format(ab, " error=%d", aad(sa)->error); 72 } 73 74 if (aad(sa)->label) { 75 struct aa_label *label = aad(sa)->label; 76 77 if (label_isprofile(label)) { 78 struct aa_profile *profile = labels_profile(label); 79 80 if (profile->ns != root_ns) { 81 audit_log_format(ab, " namespace="); 82 audit_log_untrustedstring(ab, 83 profile->ns->base.hname); 84 } 85 audit_log_format(ab, " profile="); 86 audit_log_untrustedstring(ab, profile->base.hname); 87 } else { 88 audit_log_format(ab, " label="); 89 aa_label_xaudit(ab, root_ns, label, FLAG_VIEW_SUBNS, 90 GFP_ATOMIC); 91 } 92 } 93 94 if (aad(sa)->name) { 95 audit_log_format(ab, " name="); 96 audit_log_untrustedstring(ab, aad(sa)->name); 97 } 98 } 99 100 /** 101 * aa_audit_msg - Log a message to the audit subsystem 102 * @sa: audit event structure (NOT NULL) 103 * @cb: optional callback fn for type specific fields (MAYBE NULL) 104 */ 105 void aa_audit_msg(int type, struct common_audit_data *sa, 106 void (*cb) (struct audit_buffer *, void *)) 107 { 108 aad(sa)->type = type; 109 common_lsm_audit(sa, audit_pre, cb); 110 } 111 112 /** 113 * aa_audit - Log a profile based audit event to the audit subsystem 114 * @type: audit type for the message 115 * @profile: profile to check against (NOT NULL) 116 * @sa: audit event (NOT NULL) 117 * @cb: optional callback fn for type specific fields (MAYBE NULL) 118 * 119 * Handle default message switching based off of audit mode flags 120 * 121 * Returns: error on failure 122 */ 123 int aa_audit(int type, struct aa_profile *profile, struct common_audit_data *sa, 124 void (*cb) (struct audit_buffer *, void *)) 125 { 126 AA_BUG(!profile); 127 128 if (type == AUDIT_APPARMOR_AUTO) { 129 if (likely(!aad(sa)->error)) { 130 if (AUDIT_MODE(profile) != AUDIT_ALL) 131 return 0; 132 type = AUDIT_APPARMOR_AUDIT; 133 } else if (COMPLAIN_MODE(profile)) 134 type = AUDIT_APPARMOR_ALLOWED; 135 else 136 type = AUDIT_APPARMOR_DENIED; 137 } 138 if (AUDIT_MODE(profile) == AUDIT_QUIET || 139 (type == AUDIT_APPARMOR_DENIED && 140 AUDIT_MODE(profile) == AUDIT_QUIET_DENIED)) 141 return aad(sa)->error; 142 143 if (KILL_MODE(profile) && type == AUDIT_APPARMOR_DENIED) 144 type = AUDIT_APPARMOR_KILL; 145 146 aad(sa)->label = &profile->label; 147 148 aa_audit_msg(type, sa, cb); 149 150 if (aad(sa)->type == AUDIT_APPARMOR_KILL) 151 (void)send_sig_info(SIGKILL, NULL, 152 sa->type == LSM_AUDIT_DATA_TASK && sa->u.tsk ? 153 sa->u.tsk : current); 154 155 if (aad(sa)->type == AUDIT_APPARMOR_ALLOWED) 156 return complain_error(aad(sa)->error); 157 158 return aad(sa)->error; 159 } 160 161 struct aa_audit_rule { 162 struct aa_label *label; 163 }; 164 165 void aa_audit_rule_free(void *vrule) 166 { 167 struct aa_audit_rule *rule = vrule; 168 169 if (rule) { 170 if (!IS_ERR(rule->label)) 171 aa_put_label(rule->label); 172 kfree(rule); 173 } 174 } 175 176 int aa_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) 177 { 178 struct aa_audit_rule *rule; 179 180 switch (field) { 181 case AUDIT_SUBJ_ROLE: 182 if (op != Audit_equal && op != Audit_not_equal) 183 return -EINVAL; 184 break; 185 default: 186 return -EINVAL; 187 } 188 189 rule = kzalloc(sizeof(struct aa_audit_rule), GFP_KERNEL); 190 191 if (!rule) 192 return -ENOMEM; 193 194 /* Currently rules are treated as coming from the root ns */ 195 rule->label = aa_label_parse(&root_ns->unconfined->label, rulestr, 196 GFP_KERNEL, true, false); 197 if (IS_ERR(rule->label)) { 198 int err = PTR_ERR(rule->label); 199 aa_audit_rule_free(rule); 200 return err; 201 } 202 203 *vrule = rule; 204 return 0; 205 } 206 207 int aa_audit_rule_known(struct audit_krule *rule) 208 { 209 int i; 210 211 for (i = 0; i < rule->field_count; i++) { 212 struct audit_field *f = &rule->fields[i]; 213 214 switch (f->type) { 215 case AUDIT_SUBJ_ROLE: 216 return 1; 217 } 218 } 219 220 return 0; 221 } 222 223 int aa_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule) 224 { 225 struct aa_audit_rule *rule = vrule; 226 struct aa_label *label; 227 int found = 0; 228 229 label = aa_secid_to_label(sid); 230 231 if (!label) 232 return -ENOENT; 233 234 if (aa_label_is_subset(label, rule->label)) 235 found = 1; 236 237 switch (field) { 238 case AUDIT_SUBJ_ROLE: 239 switch (op) { 240 case Audit_equal: 241 return found; 242 case Audit_not_equal: 243 return !found; 244 } 245 } 246 return 0; 247 } 248