net/mptcp/pm_userspace.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Multipath TCP
   3  *
   4  * Copyright (c) 2022, Intel Corporation.
   5  */
   6
   7 #include "protocol.h"
   8
   9 void mptcp_free_local_addr_list(struct mptcp_sock *msk)
  10 {
  11         struct mptcp_pm_addr_entry *entry, *tmp;
  12         struct sock *sk = (struct sock *)msk;
  13         LIST_HEAD(free_list);
  14
  15         if (!mptcp_pm_is_userspace(msk))
  16                 return;
  17
  18         spin_lock_bh(&msk->pm.lock);
  19         list_splice_init(&msk->pm.userspace_pm_local_addr_list, &free_list);
  20         spin_unlock_bh(&msk->pm.lock);
  21
  22         list_for_each_entry_safe(entry, tmp, &free_list, list) {
  23                 sock_kfree_s(sk, entry, sizeof(*entry));
  24         }
  25 }
  26
  27 int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk,
  28                                              struct mptcp_pm_addr_entry *entry)
  29 {
  30         DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
  31         struct mptcp_pm_addr_entry *match = NULL;
  32         struct sock *sk = (struct sock *)msk;
  33         struct mptcp_pm_addr_entry *e;
  34         bool addr_match = false;
  35         bool id_match = false;
  36         int ret = -EINVAL;
  37
  38         bitmap_zero(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
  39
  40         spin_lock_bh(&msk->pm.lock);
  41         list_for_each_entry(e, &msk->pm.userspace_pm_local_addr_list, list) {
  42                 addr_match = mptcp_addresses_equal(&e->addr, &entry->addr, true);
  43                 if (addr_match && entry->addr.id == 0)
  44                         entry->addr.id = e->addr.id;
  45                 id_match = (e->addr.id == entry->addr.id);
  46                 if (addr_match && id_match) {
  47                         match = e;
  48                         break;
  49                 } else if (addr_match || id_match) {
  50                         break;
  51                 }
  52                 __set_bit(e->addr.id, id_bitmap);
  53         }
  54
  55         if (!match && !addr_match && !id_match) {
  56                 /* Memory for the entry is allocated from the
  57                  * sock option buffer.
  58                  */
  59                 e = sock_kmalloc(sk, sizeof(*e), GFP_ATOMIC);
  60                 if (!e) {
  61                         spin_unlock_bh(&msk->pm.lock);
  62                         return -ENOMEM;
  63                 }
  64
  65                 *e = *entry;
  66                 if (!e->addr.id)
  67                         e->addr.id = find_next_zero_bit(id_bitmap,
  68                                                         MPTCP_PM_MAX_ADDR_ID + 1,
  69                                                         1);
  70                 list_add_tail_rcu(&e->list, &msk->pm.userspace_pm_local_addr_list);
  71                 ret = e->addr.id;
  72         } else if (match) {
  73                 ret = entry->addr.id;
  74         }
  75
  76         spin_unlock_bh(&msk->pm.lock);
  77         return ret;
  78 }
  79
  80 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk,
  81                                                    unsigned int id,
  82                                                    u8 *flags, int *ifindex)
  83 {
  84         struct mptcp_pm_addr_entry *entry, *match = NULL;
  85
  86         *flags = 0;
  87         *ifindex = 0;
  88
  89         spin_lock_bh(&msk->pm.lock);
  90         list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) {
  91                 if (id == entry->addr.id) {
  92                         match = entry;
  93                         break;
  94                 }
  95         }
  96         spin_unlock_bh(&msk->pm.lock);
  97         if (match) {
  98                 *flags = match->flags;
  99                 *ifindex = match->ifindex;
 100         }
 101
 102         return 0;
 103 }
 104
 105 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk,
 106                                     struct mptcp_addr_info *skc)
 107 {
 108         struct mptcp_pm_addr_entry new_entry;
 109         __be16 msk_sport =  ((struct inet_sock *)
 110                              inet_sk((struct sock *)msk))->inet_sport;
 111
 112         memset(&new_entry, 0, sizeof(struct mptcp_pm_addr_entry));
 113         new_entry.addr = *skc;
 114         new_entry.addr.id = 0;
 115         new_entry.flags = MPTCP_PM_ADDR_FLAG_IMPLICIT;
 116
 117         if (new_entry.addr.port == msk_sport)
 118                 new_entry.addr.port = 0;
 119
 120         return mptcp_userspace_pm_append_new_local_addr(msk, &new_entry);
 121 }
 122
 123 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info)
 124 {
 125         struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
 126         struct nlattr *addr = info->attrs[MPTCP_PM_ATTR_ADDR];
 127         struct mptcp_pm_addr_entry addr_val;
 128         struct mptcp_sock *msk;
 129         int err = -EINVAL;
 130         u32 token_val;
 131
 132         if (!addr || !token) {
 133                 GENL_SET_ERR_MSG(info, "missing required inputs");
 134                 return err;
 135         }
 136
 137         token_val = nla_get_u32(token);
 138
 139         msk = mptcp_token_get_sock(sock_net(skb->sk), token_val);
 140         if (!msk) {
 141                 NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
 142                 return err;
 143         }
 144
 145         if (!mptcp_pm_is_userspace(msk)) {
 146                 GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
 147                 goto announce_err;
 148         }
 149
 150         err = mptcp_pm_parse_entry(addr, info, true, &addr_val);
 151         if (err < 0) {
 152                 GENL_SET_ERR_MSG(info, "error parsing local address");
 153                 goto announce_err;
 154         }
 155
 156         if (addr_val.addr.id == 0 || !(addr_val.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) {
 157                 GENL_SET_ERR_MSG(info, "invalid addr id or flags");
 158                 goto announce_err;
 159         }
 160
 161         err = mptcp_userspace_pm_append_new_local_addr(msk, &addr_val);
 162         if (err < 0) {
 163                 GENL_SET_ERR_MSG(info, "did not match address and id");
 164                 goto announce_err;
 165         }
 166
 167         lock_sock((struct sock *)msk);
 168         spin_lock_bh(&msk->pm.lock);
 169
 170         if (mptcp_pm_alloc_anno_list(msk, &addr_val)) {
 171                 mptcp_pm_announce_addr(msk, &addr_val.addr, false);
 172                 mptcp_pm_nl_addr_send_ack(msk);
 173         }
 174
 175         spin_unlock_bh(&msk->pm.lock);
 176         release_sock((struct sock *)msk);
 177
 178         err = 0;
 179  announce_err:
 180         sock_put((struct sock *)msk);
 181         return err;
 182 }
 183
 184 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info)
 185 {
 186         struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
 187         struct nlattr *id = info->attrs[MPTCP_PM_ATTR_LOC_ID];
 188         struct mptcp_pm_addr_entry *match = NULL;
 189         struct mptcp_pm_addr_entry *entry;
 190         struct mptcp_sock *msk;
 191         LIST_HEAD(free_list);
 192         int err = -EINVAL;
 193         u32 token_val;
 194         u8 id_val;
 195
 196         if (!id || !token) {
 197                 GENL_SET_ERR_MSG(info, "missing required inputs");
 198                 return err;
 199         }
 200
 201         id_val = nla_get_u8(id);
 202         token_val = nla_get_u32(token);
 203
 204         msk = mptcp_token_get_sock(sock_net(skb->sk), token_val);
 205         if (!msk) {
 206                 NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
 207                 return err;
 208         }
 209
 210         if (!mptcp_pm_is_userspace(msk)) {
 211                 GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
 212                 goto remove_err;
 213         }
 214
 215         lock_sock((struct sock *)msk);
 216
 217         list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) {
 218                 if (entry->addr.id == id_val) {
 219                         match = entry;
 220                         break;
 221                 }
 222         }
 223
 224         if (!match) {
 225                 GENL_SET_ERR_MSG(info, "address with specified id not found");
 226                 release_sock((struct sock *)msk);
 227                 goto remove_err;
 228         }
 229
 230         list_move(&match->list, &free_list);
 231
 232         mptcp_pm_remove_addrs_and_subflows(msk, &free_list);
 233
 234         release_sock((struct sock *)msk);
 235
 236         list_for_each_entry_safe(match, entry, &free_list, list) {
 237                 sock_kfree_s((struct sock *)msk, match, sizeof(*match));
 238         }
 239
 240         err = 0;
 241  remove_err:
 242         sock_put((struct sock *)msk);
 243         return err;
 244 }
 245
 246 int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info)
 247 {
 248         struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
 249         struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
 250         struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR];
 251         struct mptcp_addr_info addr_r;
 252         struct mptcp_addr_info addr_l;
 253         struct mptcp_sock *msk;
 254         int err = -EINVAL;
 255         struct sock *sk;
 256         u32 token_val;
 257
 258         if (!laddr || !raddr || !token) {
 259                 GENL_SET_ERR_MSG(info, "missing required inputs");
 260                 return err;
 261         }
 262
 263         token_val = nla_get_u32(token);
 264
 265         msk = mptcp_token_get_sock(genl_info_net(info), token_val);
 266         if (!msk) {
 267                 NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
 268                 return err;
 269         }
 270
 271         if (!mptcp_pm_is_userspace(msk)) {
 272                 GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
 273                 goto create_err;
 274         }
 275
 276         err = mptcp_pm_parse_addr(laddr, info, &addr_l);
 277         if (err < 0) {
 278                 NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr");
 279                 goto create_err;
 280         }
 281
 282         if (addr_l.id == 0) {
 283                 NL_SET_ERR_MSG_ATTR(info->extack, laddr, "missing local addr id");
 284                 goto create_err;
 285         }
 286
 287         err = mptcp_pm_parse_addr(raddr, info, &addr_r);
 288         if (err < 0) {
 289                 NL_SET_ERR_MSG_ATTR(info->extack, raddr, "error parsing remote addr");
 290                 goto create_err;
 291         }
 292
 293         sk = &msk->sk.icsk_inet.sk;
 294         lock_sock(sk);
 295
 296         err = __mptcp_subflow_connect(sk, &addr_l, &addr_r);
 297
 298         release_sock(sk);
 299
 300  create_err:
 301         sock_put((struct sock *)msk);
 302         return err;
 303 }
 304
 305 static struct sock *mptcp_nl_find_ssk(struct mptcp_sock *msk,
 306                                       const struct mptcp_addr_info *local,
 307                                       const struct mptcp_addr_info *remote)
 308 {
 309         struct sock *sk = &msk->sk.icsk_inet.sk;
 310         struct mptcp_subflow_context *subflow;
 311         struct sock *found = NULL;
 312
 313         if (local->family != remote->family)
 314                 return NULL;
 315
 316         lock_sock(sk);
 317
 318         mptcp_for_each_subflow(msk, subflow) {
 319                 const struct inet_sock *issk;
 320                 struct sock *ssk;
 321
 322                 ssk = mptcp_subflow_tcp_sock(subflow);
 323
 324                 if (local->family != ssk->sk_family)
 325                         continue;
 326
 327                 issk = inet_sk(ssk);
 328
 329                 switch (ssk->sk_family) {
 330                 case AF_INET:
 331                         if (issk->inet_saddr != local->addr.s_addr ||
 332                             issk->inet_daddr != remote->addr.s_addr)
 333                                 continue;
 334                         break;
 335 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
 336                 case AF_INET6: {
 337                         const struct ipv6_pinfo *pinfo = inet6_sk(ssk);
 338
 339                         if (!ipv6_addr_equal(&local->addr6, &pinfo->saddr) ||
 340                             !ipv6_addr_equal(&remote->addr6, &ssk->sk_v6_daddr))
 341                                 continue;
 342                         break;
 343                 }
 344 #endif
 345                 default:
 346                         continue;
 347                 }
 348
 349                 if (issk->inet_sport == local->port &&
 350                     issk->inet_dport == remote->port) {
 351                         found = ssk;
 352                         goto found;
 353                 }
 354         }
 355
 356 found:
 357         release_sock(sk);
 358
 359         return found;
 360 }
 361
 362 int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info)
 363 {
 364         struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
 365         struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
 366         struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR];
 367         struct mptcp_addr_info addr_l;
 368         struct mptcp_addr_info addr_r;
 369         struct mptcp_sock *msk;
 370         struct sock *sk, *ssk;
 371         int err = -EINVAL;
 372         u32 token_val;
 373
 374         if (!laddr || !raddr || !token) {
 375                 GENL_SET_ERR_MSG(info, "missing required inputs");
 376                 return err;
 377         }
 378
 379         token_val = nla_get_u32(token);
 380
 381         msk = mptcp_token_get_sock(genl_info_net(info), token_val);
 382         if (!msk) {
 383                 NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
 384                 return err;
 385         }
 386
 387         if (!mptcp_pm_is_userspace(msk)) {
 388                 GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
 389                 goto destroy_err;
 390         }
 391
 392         err = mptcp_pm_parse_addr(laddr, info, &addr_l);
 393         if (err < 0) {
 394                 NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr");
 395                 goto destroy_err;
 396         }
 397
 398         err = mptcp_pm_parse_addr(raddr, info, &addr_r);
 399         if (err < 0) {
 400                 NL_SET_ERR_MSG_ATTR(info->extack, raddr, "error parsing remote addr");
 401                 goto destroy_err;
 402         }
 403
 404         if (addr_l.family != addr_r.family) {
 405                 GENL_SET_ERR_MSG(info, "address families do not match");
 406                 goto destroy_err;
 407         }
 408
 409         if (!addr_l.port || !addr_r.port) {
 410                 GENL_SET_ERR_MSG(info, "missing local or remote port");
 411                 goto destroy_err;
 412         }
 413
 414         sk = &msk->sk.icsk_inet.sk;
 415         ssk = mptcp_nl_find_ssk(msk, &addr_l, &addr_r);
 416         if (ssk) {
 417                 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
 418
 419                 mptcp_subflow_shutdown(sk, ssk, RCV_SHUTDOWN | SEND_SHUTDOWN);
 420                 mptcp_close_ssk(sk, ssk, subflow);
 421                 err = 0;
 422         } else {
 423                 err = -ESRCH;
 424         }
 425
 426  destroy_err:
 427         sock_put((struct sock *)msk);
 428         return err;
 429 }