security/apparmor/net.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * AppArmor security module
   4  *
   5  * This file contains AppArmor network mediation
   6  *
   7  * Copyright (C) 1998-2008 Novell/SUSE
   8  * Copyright 2009-2017 Canonical Ltd.
   9  */
  10
  11 #include "include/apparmor.h"
  12 #include "include/audit.h"
  13 #include "include/cred.h"
  14 #include "include/label.h"
  15 #include "include/net.h"
  16 #include "include/policy.h"
  17 #include "include/secid.h"
  18
  19 #include "net_names.h"
  20
  21
  22 struct aa_sfs_entry aa_sfs_entry_network[] = {
  23         AA_SFS_FILE_STRING("af_mask",   AA_SFS_AF_MASK),
  24         { }
  25 };
  26
  27 static const char * const net_mask_names[] = {
  28         "unknown",
  29         "send",
  30         "receive",
  31         "unknown",
  32
  33         "create",
  34         "shutdown",
  35         "connect",
  36         "unknown",
  37
  38         "setattr",
  39         "getattr",
  40         "setcred",
  41         "getcred",
  42
  43         "chmod",
  44         "chown",
  45         "chgrp",
  46         "lock",
  47
  48         "mmap",
  49         "mprot",
  50         "unknown",
  51         "unknown",
  52
  53         "accept",
  54         "bind",
  55         "listen",
  56         "unknown",
  57
  58         "setopt",
  59         "getopt",
  60         "unknown",
  61         "unknown",
  62
  63         "unknown",
  64         "unknown",
  65         "unknown",
  66         "unknown",
  67 };
  68
  69
  70 /* audit callback for net specific fields */
  71 void audit_net_cb(struct audit_buffer *ab, void *va)
  72 {
  73         struct common_audit_data *sa = va;
  74
  75         if (address_family_names[sa->u.net->family])
  76                 audit_log_format(ab, " family=\"%s\"",
  77                                  address_family_names[sa->u.net->family]);
  78         else
  79                 audit_log_format(ab, " family=\"unknown(%d)\"",
  80                                  sa->u.net->family);
  81         if (sock_type_names[aad(sa)->net.type])
  82                 audit_log_format(ab, " sock_type=\"%s\"",
  83                                  sock_type_names[aad(sa)->net.type]);
  84         else
  85                 audit_log_format(ab, " sock_type=\"unknown(%d)\"",
  86                                  aad(sa)->net.type);
  87         audit_log_format(ab, " protocol=%d", aad(sa)->net.protocol);
  88
  89         if (aad(sa)->request & NET_PERMS_MASK) {
  90                 audit_log_format(ab, " requested_mask=");
  91                 aa_audit_perm_mask(ab, aad(sa)->request, NULL, 0,
  92                                    net_mask_names, NET_PERMS_MASK);
  93
  94                 if (aad(sa)->denied & NET_PERMS_MASK) {
  95                         audit_log_format(ab, " denied_mask=");
  96                         aa_audit_perm_mask(ab, aad(sa)->denied, NULL, 0,
  97                                            net_mask_names, NET_PERMS_MASK);
  98                 }
  99         }
 100         if (aad(sa)->peer) {
 101                 audit_log_format(ab, " peer=");
 102                 aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,
 103                                 FLAGS_NONE, GFP_ATOMIC);
 104         }
 105 }
 106
 107 /* Generic af perm */
 108 int aa_profile_af_perm(struct aa_profile *profile, struct common_audit_data *sa,
 109                        u32 request, u16 family, int type)
 110 {
 111         struct aa_perms perms = { };
 112         unsigned int state;
 113         __be16 buffer[2];
 114
 115         AA_BUG(family >= AF_MAX);
 116         AA_BUG(type < 0 || type >= SOCK_MAX);
 117
 118         if (profile_unconfined(profile))
 119                 return 0;
 120         state = PROFILE_MEDIATES(profile, AA_CLASS_NET);
 121         if (!state)
 122                 return 0;
 123
 124         buffer[0] = cpu_to_be16(family);
 125         buffer[1] = cpu_to_be16((u16) type);
 126         state = aa_dfa_match_len(profile->policy.dfa, state, (char *) &buffer,
 127                                  4);
 128         aa_compute_perms(profile->policy.dfa, state, &perms);
 129         aa_apply_modes_to_perms(profile, &perms);
 130
 131         return aa_check_perms(profile, &perms, request, sa, audit_net_cb);
 132 }
 133
 134 int aa_af_perm(struct aa_label *label, const char *op, u32 request, u16 family,
 135                int type, int protocol)
 136 {
 137         struct aa_profile *profile;
 138         DEFINE_AUDIT_NET(sa, op, NULL, family, type, protocol);
 139
 140         return fn_for_each_confined(label, profile,
 141                         aa_profile_af_perm(profile, &sa, request, family,
 142                                            type));
 143 }
 144
 145 static int aa_label_sk_perm(struct aa_label *label, const char *op, u32 request,
 146                             struct sock *sk)
 147 {
 148         int error = 0;
 149
 150         AA_BUG(!label);
 151         AA_BUG(!sk);
 152
 153         if (!unconfined(label)) {
 154                 struct aa_profile *profile;
 155                 DEFINE_AUDIT_SK(sa, op, sk);
 156
 157                 error = fn_for_each_confined(label, profile,
 158                             aa_profile_af_sk_perm(profile, &sa, request, sk));
 159         }
 160
 161         return error;
 162 }
 163
 164 int aa_sk_perm(const char *op, u32 request, struct sock *sk)
 165 {
 166         struct aa_label *label;
 167         int error;
 168
 169         AA_BUG(!sk);
 170         AA_BUG(in_interrupt());
 171
 172         /* TODO: switch to begin_current_label ???? */
 173         label = begin_current_label_crit_section();
 174         error = aa_label_sk_perm(label, op, request, sk);
 175         end_current_label_crit_section(label);
 176
 177         return error;
 178 }
 179
 180
 181 int aa_sock_file_perm(struct aa_label *label, const char *op, u32 request,
 182                       struct socket *sock)
 183 {
 184         AA_BUG(!label);
 185         AA_BUG(!sock);
 186         AA_BUG(!sock->sk);
 187
 188         return aa_label_sk_perm(label, op, request, sock->sk);
 189 }
 190
 191 #ifdef CONFIG_NETWORK_SECMARK
 192 static int apparmor_secmark_init(struct aa_secmark *secmark)
 193 {
 194         struct aa_label *label;
 195
 196         if (secmark->label[0] == '*') {
 197                 secmark->secid = AA_SECID_WILDCARD;
 198                 return 0;
 199         }
 200
 201         label = aa_label_strn_parse(&root_ns->unconfined->label,
 202                                     secmark->label, strlen(secmark->label),
 203                                     GFP_ATOMIC, false, false);
 204
 205         if (IS_ERR(label))
 206                 return PTR_ERR(label);
 207
 208         secmark->secid = label->secid;
 209
 210         return 0;
 211 }
 212
 213 static int aa_secmark_perm(struct aa_profile *profile, u32 request, u32 secid,
 214                            struct common_audit_data *sa)
 215 {
 216         int i, ret;
 217         struct aa_perms perms = { };
 218
 219         if (profile->secmark_count == 0)
 220                 return 0;
 221
 222         for (i = 0; i < profile->secmark_count; i++) {
 223                 if (!profile->secmark[i].secid) {
 224                         ret = apparmor_secmark_init(&profile->secmark[i]);
 225                         if (ret)
 226                                 return ret;
 227                 }
 228
 229                 if (profile->secmark[i].secid == secid ||
 230                     profile->secmark[i].secid == AA_SECID_WILDCARD) {
 231                         if (profile->secmark[i].deny)
 232                                 perms.deny = ALL_PERMS_MASK;
 233                         else
 234                                 perms.allow = ALL_PERMS_MASK;
 235
 236                         if (profile->secmark[i].audit)
 237                                 perms.audit = ALL_PERMS_MASK;
 238                 }
 239         }
 240
 241         aa_apply_modes_to_perms(profile, &perms);
 242
 243         return aa_check_perms(profile, &perms, request, sa, audit_net_cb);
 244 }
 245
 246 int apparmor_secmark_check(struct aa_label *label, char *op, u32 request,
 247                            u32 secid, const struct sock *sk)
 248 {
 249         struct aa_profile *profile;
 250         DEFINE_AUDIT_SK(sa, op, sk);
 251
 252         return fn_for_each_confined(label, profile,
 253                                     aa_secmark_perm(profile, request, secid,
 254                                                     &sa));
 255 }
 256 #endif