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         audit_log_format(ab, " family=");
  76         if (address_family_names[sa->u.net->family])
  77                 audit_log_string(ab, address_family_names[sa->u.net->family]);
  78         else
  79                 audit_log_format(ab, "\"unknown(%d)\"", sa->u.net->family);
  80         audit_log_format(ab, " sock_type=");
  81         if (sock_type_names[aad(sa)->net.type])
  82                 audit_log_string(ab, sock_type_names[aad(sa)->net.type]);
  83         else
  84                 audit_log_format(ab, "\"unknown(%d)\"", aad(sa)->net.type);
  85         audit_log_format(ab, " protocol=%d", aad(sa)->net.protocol);
  86
  87         if (aad(sa)->request & NET_PERMS_MASK) {
  88                 audit_log_format(ab, " requested_mask=");
  89                 aa_audit_perm_mask(ab, aad(sa)->request, NULL, 0,
  90                                    net_mask_names, NET_PERMS_MASK);
  91
  92                 if (aad(sa)->denied & NET_PERMS_MASK) {
  93                         audit_log_format(ab, " denied_mask=");
  94                         aa_audit_perm_mask(ab, aad(sa)->denied, NULL, 0,
  95                                            net_mask_names, NET_PERMS_MASK);
  96                 }
  97         }
  98         if (aad(sa)->peer) {
  99                 audit_log_format(ab, " peer=");
 100                 aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,
 101                                 FLAGS_NONE, GFP_ATOMIC);
 102         }
 103 }
 104
 105 /* Generic af perm */
 106 int aa_profile_af_perm(struct aa_profile *profile, struct common_audit_data *sa,
 107                        u32 request, u16 family, int type)
 108 {
 109         struct aa_perms perms = { };
 110         unsigned int state;
 111         __be16 buffer[2];
 112
 113         AA_BUG(family >= AF_MAX);
 114         AA_BUG(type < 0 || type >= SOCK_MAX);
 115
 116         if (profile_unconfined(profile))
 117                 return 0;
 118         state = PROFILE_MEDIATES(profile, AA_CLASS_NET);
 119         if (!state)
 120                 return 0;
 121
 122         buffer[0] = cpu_to_be16(family);
 123         buffer[1] = cpu_to_be16((u16) type);
 124         state = aa_dfa_match_len(profile->policy.dfa, state, (char *) &buffer,
 125                                  4);
 126         aa_compute_perms(profile->policy.dfa, state, &perms);
 127         aa_apply_modes_to_perms(profile, &perms);
 128
 129         return aa_check_perms(profile, &perms, request, sa, audit_net_cb);
 130 }
 131
 132 int aa_af_perm(struct aa_label *label, const char *op, u32 request, u16 family,
 133                int type, int protocol)
 134 {
 135         struct aa_profile *profile;
 136         DEFINE_AUDIT_NET(sa, op, NULL, family, type, protocol);
 137
 138         return fn_for_each_confined(label, profile,
 139                         aa_profile_af_perm(profile, &sa, request, family,
 140                                            type));
 141 }
 142
 143 static int aa_label_sk_perm(struct aa_label *label, const char *op, u32 request,
 144                             struct sock *sk)
 145 {
 146         int error = 0;
 147
 148         AA_BUG(!label);
 149         AA_BUG(!sk);
 150
 151         if (!unconfined(label)) {
 152                 struct aa_profile *profile;
 153                 DEFINE_AUDIT_SK(sa, op, sk);
 154
 155                 error = fn_for_each_confined(label, profile,
 156                             aa_profile_af_sk_perm(profile, &sa, request, sk));
 157         }
 158
 159         return error;
 160 }
 161
 162 int aa_sk_perm(const char *op, u32 request, struct sock *sk)
 163 {
 164         struct aa_label *label;
 165         int error;
 166
 167         AA_BUG(!sk);
 168         AA_BUG(in_interrupt());
 169
 170         /* TODO: switch to begin_current_label ???? */
 171         label = begin_current_label_crit_section();
 172         error = aa_label_sk_perm(label, op, request, sk);
 173         end_current_label_crit_section(label);
 174
 175         return error;
 176 }
 177
 178
 179 int aa_sock_file_perm(struct aa_label *label, const char *op, u32 request,
 180                       struct socket *sock)
 181 {
 182         AA_BUG(!label);
 183         AA_BUG(!sock);
 184         AA_BUG(!sock->sk);
 185
 186         return aa_label_sk_perm(label, op, request, sock->sk);
 187 }
 188
 189 #ifdef CONFIG_NETWORK_SECMARK
 190 static int apparmor_secmark_init(struct aa_secmark *secmark)
 191 {
 192         struct aa_label *label;
 193
 194         if (secmark->label[0] == '*') {
 195                 secmark->secid = AA_SECID_WILDCARD;
 196                 return 0;
 197         }
 198
 199         label = aa_label_strn_parse(&root_ns->unconfined->label,
 200                                     secmark->label, strlen(secmark->label),
 201                                     GFP_ATOMIC, false, false);
 202
 203         if (IS_ERR(label))
 204                 return PTR_ERR(label);
 205
 206         secmark->secid = label->secid;
 207
 208         return 0;
 209 }
 210
 211 static int aa_secmark_perm(struct aa_profile *profile, u32 request, u32 secid,
 212                            struct common_audit_data *sa, struct sock *sk)
 213 {
 214         int i, ret;
 215         struct aa_perms perms = { };
 216
 217         if (profile->secmark_count == 0)
 218                 return 0;
 219
 220         for (i = 0; i < profile->secmark_count; i++) {
 221                 if (!profile->secmark[i].secid) {
 222                         ret = apparmor_secmark_init(&profile->secmark[i]);
 223                         if (ret)
 224                                 return ret;
 225                 }
 226
 227                 if (profile->secmark[i].secid == secid ||
 228                     profile->secmark[i].secid == AA_SECID_WILDCARD) {
 229                         if (profile->secmark[i].deny)
 230                                 perms.deny = ALL_PERMS_MASK;
 231                         else
 232                                 perms.allow = ALL_PERMS_MASK;
 233
 234                         if (profile->secmark[i].audit)
 235                                 perms.audit = ALL_PERMS_MASK;
 236                 }
 237         }
 238
 239         aa_apply_modes_to_perms(profile, &perms);
 240
 241         return aa_check_perms(profile, &perms, request, sa, audit_net_cb);
 242 }
 243
 244 int apparmor_secmark_check(struct aa_label *label, char *op, u32 request,
 245                            u32 secid, struct sock *sk)
 246 {
 247         struct aa_profile *profile;
 248         DEFINE_AUDIT_SK(sa, op, sk);
 249
 250         return fn_for_each_confined(label, profile,
 251                                     aa_secmark_perm(profile, request, secid,
 252                                                     &sa, sk));
 253 }
 254 #endif