1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * XFRM virtual interface 4 * 5 * Copyright (C) 2018 secunet Security Networks AG 6 * 7 * Author: 8 * Steffen Klassert <steffen.klassert@secunet.com> 9 */ 10 11 #include <linux/module.h> 12 #include <linux/capability.h> 13 #include <linux/errno.h> 14 #include <linux/types.h> 15 #include <linux/sockios.h> 16 #include <linux/icmp.h> 17 #include <linux/if.h> 18 #include <linux/in.h> 19 #include <linux/ip.h> 20 #include <linux/net.h> 21 #include <linux/in6.h> 22 #include <linux/netdevice.h> 23 #include <linux/if_link.h> 24 #include <linux/if_arp.h> 25 #include <linux/icmpv6.h> 26 #include <linux/init.h> 27 #include <linux/route.h> 28 #include <linux/rtnetlink.h> 29 #include <linux/netfilter_ipv6.h> 30 #include <linux/slab.h> 31 #include <linux/hash.h> 32 33 #include <linux/uaccess.h> 34 #include <linux/atomic.h> 35 36 #include <net/gso.h> 37 #include <net/icmp.h> 38 #include <net/ip.h> 39 #include <net/ipv6.h> 40 #include <net/ip6_route.h> 41 #include <net/ip_tunnels.h> 42 #include <net/addrconf.h> 43 #include <net/xfrm.h> 44 #include <net/net_namespace.h> 45 #include <net/dst_metadata.h> 46 #include <net/netns/generic.h> 47 #include <linux/etherdevice.h> 48 49 static int xfrmi_dev_init(struct net_device *dev); 50 static void xfrmi_dev_setup(struct net_device *dev); 51 static struct rtnl_link_ops xfrmi_link_ops __read_mostly; 52 static unsigned int xfrmi_net_id __read_mostly; 53 static const struct net_device_ops xfrmi_netdev_ops; 54 55 #define XFRMI_HASH_BITS 8 56 #define XFRMI_HASH_SIZE BIT(XFRMI_HASH_BITS) 57 58 struct xfrmi_net { 59 /* lists for storing interfaces in use */ 60 struct xfrm_if __rcu *xfrmi[XFRMI_HASH_SIZE]; 61 struct xfrm_if __rcu *collect_md_xfrmi; 62 }; 63 64 static const struct nla_policy xfrm_lwt_policy[LWT_XFRM_MAX + 1] = { 65 [LWT_XFRM_IF_ID] = NLA_POLICY_MIN(NLA_U32, 1), 66 [LWT_XFRM_LINK] = NLA_POLICY_MIN(NLA_U32, 1), 67 }; 68 69 static void xfrmi_destroy_state(struct lwtunnel_state *lwt) 70 { 71 } 72 73 static int xfrmi_build_state(struct net *net, struct nlattr *nla, 74 unsigned int family, const void *cfg, 75 struct lwtunnel_state **ts, 76 struct netlink_ext_ack *extack) 77 { 78 struct nlattr *tb[LWT_XFRM_MAX + 1]; 79 struct lwtunnel_state *new_state; 80 struct xfrm_md_info *info; 81 int ret; 82 83 ret = nla_parse_nested(tb, LWT_XFRM_MAX, nla, xfrm_lwt_policy, extack); 84 if (ret < 0) 85 return ret; 86 87 if (!tb[LWT_XFRM_IF_ID]) { 88 NL_SET_ERR_MSG(extack, "if_id must be set"); 89 return -EINVAL; 90 } 91 92 new_state = lwtunnel_state_alloc(sizeof(*info)); 93 if (!new_state) { 94 NL_SET_ERR_MSG(extack, "failed to create encap info"); 95 return -ENOMEM; 96 } 97 98 new_state->type = LWTUNNEL_ENCAP_XFRM; 99 100 info = lwt_xfrm_info(new_state); 101 102 info->if_id = nla_get_u32(tb[LWT_XFRM_IF_ID]); 103 104 if (tb[LWT_XFRM_LINK]) 105 info->link = nla_get_u32(tb[LWT_XFRM_LINK]); 106 107 *ts = new_state; 108 return 0; 109 } 110 111 static int xfrmi_fill_encap_info(struct sk_buff *skb, 112 struct lwtunnel_state *lwt) 113 { 114 struct xfrm_md_info *info = lwt_xfrm_info(lwt); 115 116 if (nla_put_u32(skb, LWT_XFRM_IF_ID, info->if_id) || 117 (info->link && nla_put_u32(skb, LWT_XFRM_LINK, info->link))) 118 return -EMSGSIZE; 119 120 return 0; 121 } 122 123 static int xfrmi_encap_nlsize(struct lwtunnel_state *lwtstate) 124 { 125 return nla_total_size(sizeof(u32)) + /* LWT_XFRM_IF_ID */ 126 nla_total_size(sizeof(u32)); /* LWT_XFRM_LINK */ 127 } 128 129 static int xfrmi_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b) 130 { 131 struct xfrm_md_info *a_info = lwt_xfrm_info(a); 132 struct xfrm_md_info *b_info = lwt_xfrm_info(b); 133 134 return memcmp(a_info, b_info, sizeof(*a_info)); 135 } 136 137 static const struct lwtunnel_encap_ops xfrmi_encap_ops = { 138 .build_state = xfrmi_build_state, 139 .destroy_state = xfrmi_destroy_state, 140 .fill_encap = xfrmi_fill_encap_info, 141 .get_encap_size = xfrmi_encap_nlsize, 142 .cmp_encap = xfrmi_encap_cmp, 143 .owner = THIS_MODULE, 144 }; 145 146 #define for_each_xfrmi_rcu(start, xi) \ 147 for (xi = rcu_dereference(start); xi; xi = rcu_dereference(xi->next)) 148 149 static u32 xfrmi_hash(u32 if_id) 150 { 151 return hash_32(if_id, XFRMI_HASH_BITS); 152 } 153 154 static struct xfrm_if *xfrmi_lookup(struct net *net, struct xfrm_state *x) 155 { 156 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id); 157 struct xfrm_if *xi; 158 159 for_each_xfrmi_rcu(xfrmn->xfrmi[xfrmi_hash(x->if_id)], xi) { 160 if (x->if_id == xi->p.if_id && 161 (xi->dev->flags & IFF_UP)) 162 return xi; 163 } 164 165 xi = rcu_dereference(xfrmn->collect_md_xfrmi); 166 if (xi && (xi->dev->flags & IFF_UP)) 167 return xi; 168 169 return NULL; 170 } 171 172 static bool xfrmi_decode_session(struct sk_buff *skb, 173 unsigned short family, 174 struct xfrm_if_decode_session_result *res) 175 { 176 struct net_device *dev; 177 struct xfrm_if *xi; 178 int ifindex = 0; 179 180 if (!secpath_exists(skb) || !skb->dev) 181 return false; 182 183 switch (family) { 184 case AF_INET6: 185 ifindex = inet6_sdif(skb); 186 break; 187 case AF_INET: 188 ifindex = inet_sdif(skb); 189 break; 190 } 191 192 if (ifindex) { 193 struct net *net = xs_net(xfrm_input_state(skb)); 194 195 dev = dev_get_by_index_rcu(net, ifindex); 196 } else { 197 dev = skb->dev; 198 } 199 200 if (!dev || !(dev->flags & IFF_UP)) 201 return false; 202 if (dev->netdev_ops != &xfrmi_netdev_ops) 203 return false; 204 205 xi = netdev_priv(dev); 206 res->net = xi->net; 207 208 if (xi->p.collect_md) 209 res->if_id = xfrm_input_state(skb)->if_id; 210 else 211 res->if_id = xi->p.if_id; 212 return true; 213 } 214 215 static void xfrmi_link(struct xfrmi_net *xfrmn, struct xfrm_if *xi) 216 { 217 struct xfrm_if __rcu **xip = &xfrmn->xfrmi[xfrmi_hash(xi->p.if_id)]; 218 219 rcu_assign_pointer(xi->next , rtnl_dereference(*xip)); 220 rcu_assign_pointer(*xip, xi); 221 } 222 223 static void xfrmi_unlink(struct xfrmi_net *xfrmn, struct xfrm_if *xi) 224 { 225 struct xfrm_if __rcu **xip; 226 struct xfrm_if *iter; 227 228 for (xip = &xfrmn->xfrmi[xfrmi_hash(xi->p.if_id)]; 229 (iter = rtnl_dereference(*xip)) != NULL; 230 xip = &iter->next) { 231 if (xi == iter) { 232 rcu_assign_pointer(*xip, xi->next); 233 break; 234 } 235 } 236 } 237 238 static void xfrmi_dev_free(struct net_device *dev) 239 { 240 struct xfrm_if *xi = netdev_priv(dev); 241 242 gro_cells_destroy(&xi->gro_cells); 243 } 244 245 static int xfrmi_create(struct net_device *dev) 246 { 247 struct xfrm_if *xi = netdev_priv(dev); 248 struct net *net = dev_net(dev); 249 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id); 250 int err; 251 252 dev->rtnl_link_ops = &xfrmi_link_ops; 253 err = register_netdevice(dev); 254 if (err < 0) 255 goto out; 256 257 if (xi->p.collect_md) 258 rcu_assign_pointer(xfrmn->collect_md_xfrmi, xi); 259 else 260 xfrmi_link(xfrmn, xi); 261 262 return 0; 263 264 out: 265 return err; 266 } 267 268 static struct xfrm_if *xfrmi_locate(struct net *net, struct xfrm_if_parms *p) 269 { 270 struct xfrm_if __rcu **xip; 271 struct xfrm_if *xi; 272 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id); 273 274 for (xip = &xfrmn->xfrmi[xfrmi_hash(p->if_id)]; 275 (xi = rtnl_dereference(*xip)) != NULL; 276 xip = &xi->next) 277 if (xi->p.if_id == p->if_id) 278 return xi; 279 280 return NULL; 281 } 282 283 static void xfrmi_dev_uninit(struct net_device *dev) 284 { 285 struct xfrm_if *xi = netdev_priv(dev); 286 struct xfrmi_net *xfrmn = net_generic(xi->net, xfrmi_net_id); 287 288 if (xi->p.collect_md) 289 RCU_INIT_POINTER(xfrmn->collect_md_xfrmi, NULL); 290 else 291 xfrmi_unlink(xfrmn, xi); 292 } 293 294 static void xfrmi_scrub_packet(struct sk_buff *skb, bool xnet) 295 { 296 skb_clear_tstamp(skb); 297 skb->pkt_type = PACKET_HOST; 298 skb->skb_iif = 0; 299 skb->ignore_df = 0; 300 skb_dst_drop(skb); 301 nf_reset_ct(skb); 302 nf_reset_trace(skb); 303 304 if (!xnet) 305 return; 306 307 ipvs_reset(skb); 308 secpath_reset(skb); 309 skb_orphan(skb); 310 skb->mark = 0; 311 } 312 313 static int xfrmi_input(struct sk_buff *skb, int nexthdr, __be32 spi, 314 int encap_type, unsigned short family) 315 { 316 struct sec_path *sp; 317 318 sp = skb_sec_path(skb); 319 if (sp && (sp->len || sp->olen) && 320 !xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family)) 321 goto discard; 322 323 XFRM_SPI_SKB_CB(skb)->family = family; 324 if (family == AF_INET) { 325 XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr); 326 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL; 327 } else { 328 XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr); 329 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = NULL; 330 } 331 332 return xfrm_input(skb, nexthdr, spi, encap_type); 333 discard: 334 kfree_skb(skb); 335 return 0; 336 } 337 338 static int xfrmi4_rcv(struct sk_buff *skb) 339 { 340 return xfrmi_input(skb, ip_hdr(skb)->protocol, 0, 0, AF_INET); 341 } 342 343 static int xfrmi6_rcv(struct sk_buff *skb) 344 { 345 return xfrmi_input(skb, skb_network_header(skb)[IP6CB(skb)->nhoff], 346 0, 0, AF_INET6); 347 } 348 349 static int xfrmi4_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) 350 { 351 return xfrmi_input(skb, nexthdr, spi, encap_type, AF_INET); 352 } 353 354 static int xfrmi6_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) 355 { 356 return xfrmi_input(skb, nexthdr, spi, encap_type, AF_INET6); 357 } 358 359 static int xfrmi_rcv_cb(struct sk_buff *skb, int err) 360 { 361 const struct xfrm_mode *inner_mode; 362 struct net_device *dev; 363 struct xfrm_state *x; 364 struct xfrm_if *xi; 365 bool xnet; 366 int link; 367 368 if (err && !secpath_exists(skb)) 369 return 0; 370 371 x = xfrm_input_state(skb); 372 373 xi = xfrmi_lookup(xs_net(x), x); 374 if (!xi) 375 return 1; 376 377 link = skb->dev->ifindex; 378 dev = xi->dev; 379 skb->dev = dev; 380 381 if (err) { 382 DEV_STATS_INC(dev, rx_errors); 383 DEV_STATS_INC(dev, rx_dropped); 384 385 return 0; 386 } 387 388 xnet = !net_eq(xi->net, dev_net(skb->dev)); 389 390 if (xnet) { 391 inner_mode = &x->inner_mode; 392 393 if (x->sel.family == AF_UNSPEC) { 394 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol); 395 if (inner_mode == NULL) { 396 XFRM_INC_STATS(dev_net(skb->dev), 397 LINUX_MIB_XFRMINSTATEMODEERROR); 398 return -EINVAL; 399 } 400 } 401 402 if (!xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, 403 inner_mode->family)) 404 return -EPERM; 405 } 406 407 xfrmi_scrub_packet(skb, xnet); 408 if (xi->p.collect_md) { 409 struct metadata_dst *md_dst; 410 411 md_dst = metadata_dst_alloc(0, METADATA_XFRM, GFP_ATOMIC); 412 if (!md_dst) 413 return -ENOMEM; 414 415 md_dst->u.xfrm_info.if_id = x->if_id; 416 md_dst->u.xfrm_info.link = link; 417 skb_dst_set(skb, (struct dst_entry *)md_dst); 418 } 419 dev_sw_netstats_rx_add(dev, skb->len); 420 421 return 0; 422 } 423 424 static int 425 xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) 426 { 427 struct xfrm_if *xi = netdev_priv(dev); 428 struct dst_entry *dst = skb_dst(skb); 429 unsigned int length = skb->len; 430 struct net_device *tdev; 431 struct xfrm_state *x; 432 int err = -1; 433 u32 if_id; 434 int mtu; 435 436 if (xi->p.collect_md) { 437 struct xfrm_md_info *md_info = skb_xfrm_md_info(skb); 438 439 if (unlikely(!md_info)) 440 return -EINVAL; 441 442 if_id = md_info->if_id; 443 fl->flowi_oif = md_info->link; 444 if (md_info->dst_orig) { 445 struct dst_entry *tmp_dst = dst; 446 447 dst = md_info->dst_orig; 448 skb_dst_set(skb, dst); 449 md_info->dst_orig = NULL; 450 dst_release(tmp_dst); 451 } 452 } else { 453 if_id = xi->p.if_id; 454 } 455 456 dst_hold(dst); 457 dst = xfrm_lookup_with_ifid(xi->net, dst, fl, NULL, 0, if_id); 458 if (IS_ERR(dst)) { 459 err = PTR_ERR(dst); 460 dst = NULL; 461 goto tx_err_link_failure; 462 } 463 464 x = dst->xfrm; 465 if (!x) 466 goto tx_err_link_failure; 467 468 if (x->if_id != if_id) 469 goto tx_err_link_failure; 470 471 tdev = dst->dev; 472 473 if (tdev == dev) { 474 DEV_STATS_INC(dev, collisions); 475 net_warn_ratelimited("%s: Local routing loop detected!\n", 476 dev->name); 477 goto tx_err_dst_release; 478 } 479 480 mtu = dst_mtu(dst); 481 if ((!skb_is_gso(skb) && skb->len > mtu) || 482 (skb_is_gso(skb) && !skb_gso_validate_network_len(skb, mtu))) { 483 skb_dst_update_pmtu_no_confirm(skb, mtu); 484 485 if (skb->protocol == htons(ETH_P_IPV6)) { 486 if (mtu < IPV6_MIN_MTU) 487 mtu = IPV6_MIN_MTU; 488 489 if (skb->len > 1280) 490 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 491 else 492 goto xmit; 493 } else { 494 if (!(ip_hdr(skb)->frag_off & htons(IP_DF))) 495 goto xmit; 496 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 497 htonl(mtu)); 498 } 499 500 dst_release(dst); 501 return -EMSGSIZE; 502 } 503 504 xmit: 505 xfrmi_scrub_packet(skb, !net_eq(xi->net, dev_net(dev))); 506 skb_dst_set(skb, dst); 507 skb->dev = tdev; 508 509 err = dst_output(xi->net, skb->sk, skb); 510 if (net_xmit_eval(err) == 0) { 511 dev_sw_netstats_tx_add(dev, 1, length); 512 } else { 513 DEV_STATS_INC(dev, tx_errors); 514 DEV_STATS_INC(dev, tx_aborted_errors); 515 } 516 517 return 0; 518 tx_err_link_failure: 519 DEV_STATS_INC(dev, tx_carrier_errors); 520 dst_link_failure(skb); 521 tx_err_dst_release: 522 dst_release(dst); 523 return err; 524 } 525 526 static netdev_tx_t xfrmi_xmit(struct sk_buff *skb, struct net_device *dev) 527 { 528 struct xfrm_if *xi = netdev_priv(dev); 529 struct dst_entry *dst = skb_dst(skb); 530 struct flowi fl; 531 int ret; 532 533 memset(&fl, 0, sizeof(fl)); 534 535 switch (skb->protocol) { 536 case htons(ETH_P_IPV6): 537 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); 538 xfrm_decode_session(dev_net(dev), skb, &fl, AF_INET6); 539 if (!dst) { 540 fl.u.ip6.flowi6_oif = dev->ifindex; 541 fl.u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC; 542 dst = ip6_route_output(dev_net(dev), NULL, &fl.u.ip6); 543 if (dst->error) { 544 dst_release(dst); 545 DEV_STATS_INC(dev, tx_carrier_errors); 546 goto tx_err; 547 } 548 skb_dst_set(skb, dst); 549 } 550 break; 551 case htons(ETH_P_IP): 552 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 553 xfrm_decode_session(dev_net(dev), skb, &fl, AF_INET); 554 if (!dst) { 555 struct rtable *rt; 556 557 fl.u.ip4.flowi4_oif = dev->ifindex; 558 fl.u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC; 559 rt = __ip_route_output_key(dev_net(dev), &fl.u.ip4); 560 if (IS_ERR(rt)) { 561 DEV_STATS_INC(dev, tx_carrier_errors); 562 goto tx_err; 563 } 564 skb_dst_set(skb, &rt->dst); 565 } 566 break; 567 default: 568 goto tx_err; 569 } 570 571 fl.flowi_oif = xi->p.link; 572 573 ret = xfrmi_xmit2(skb, dev, &fl); 574 if (ret < 0) 575 goto tx_err; 576 577 return NETDEV_TX_OK; 578 579 tx_err: 580 DEV_STATS_INC(dev, tx_errors); 581 DEV_STATS_INC(dev, tx_dropped); 582 kfree_skb(skb); 583 return NETDEV_TX_OK; 584 } 585 586 static int xfrmi4_err(struct sk_buff *skb, u32 info) 587 { 588 const struct iphdr *iph = (const struct iphdr *)skb->data; 589 struct net *net = dev_net(skb->dev); 590 int protocol = iph->protocol; 591 struct ip_comp_hdr *ipch; 592 struct ip_esp_hdr *esph; 593 struct ip_auth_hdr *ah ; 594 struct xfrm_state *x; 595 struct xfrm_if *xi; 596 __be32 spi; 597 598 switch (protocol) { 599 case IPPROTO_ESP: 600 esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2)); 601 spi = esph->spi; 602 break; 603 case IPPROTO_AH: 604 ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2)); 605 spi = ah->spi; 606 break; 607 case IPPROTO_COMP: 608 ipch = (struct ip_comp_hdr *)(skb->data+(iph->ihl<<2)); 609 spi = htonl(ntohs(ipch->cpi)); 610 break; 611 default: 612 return 0; 613 } 614 615 switch (icmp_hdr(skb)->type) { 616 case ICMP_DEST_UNREACH: 617 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) 618 return 0; 619 break; 620 case ICMP_REDIRECT: 621 break; 622 default: 623 return 0; 624 } 625 626 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 627 spi, protocol, AF_INET); 628 if (!x) 629 return 0; 630 631 xi = xfrmi_lookup(net, x); 632 if (!xi) { 633 xfrm_state_put(x); 634 return -1; 635 } 636 637 if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) 638 ipv4_update_pmtu(skb, net, info, 0, protocol); 639 else 640 ipv4_redirect(skb, net, 0, protocol); 641 xfrm_state_put(x); 642 643 return 0; 644 } 645 646 static int xfrmi6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 647 u8 type, u8 code, int offset, __be32 info) 648 { 649 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; 650 struct net *net = dev_net(skb->dev); 651 int protocol = iph->nexthdr; 652 struct ip_comp_hdr *ipch; 653 struct ip_esp_hdr *esph; 654 struct ip_auth_hdr *ah; 655 struct xfrm_state *x; 656 struct xfrm_if *xi; 657 __be32 spi; 658 659 switch (protocol) { 660 case IPPROTO_ESP: 661 esph = (struct ip_esp_hdr *)(skb->data + offset); 662 spi = esph->spi; 663 break; 664 case IPPROTO_AH: 665 ah = (struct ip_auth_hdr *)(skb->data + offset); 666 spi = ah->spi; 667 break; 668 case IPPROTO_COMP: 669 ipch = (struct ip_comp_hdr *)(skb->data + offset); 670 spi = htonl(ntohs(ipch->cpi)); 671 break; 672 default: 673 return 0; 674 } 675 676 if (type != ICMPV6_PKT_TOOBIG && 677 type != NDISC_REDIRECT) 678 return 0; 679 680 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 681 spi, protocol, AF_INET6); 682 if (!x) 683 return 0; 684 685 xi = xfrmi_lookup(net, x); 686 if (!xi) { 687 xfrm_state_put(x); 688 return -1; 689 } 690 691 if (type == NDISC_REDIRECT) 692 ip6_redirect(skb, net, skb->dev->ifindex, 0, 693 sock_net_uid(net, NULL)); 694 else 695 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); 696 xfrm_state_put(x); 697 698 return 0; 699 } 700 701 static int xfrmi_change(struct xfrm_if *xi, const struct xfrm_if_parms *p) 702 { 703 if (xi->p.link != p->link) 704 return -EINVAL; 705 706 xi->p.if_id = p->if_id; 707 708 return 0; 709 } 710 711 static int xfrmi_update(struct xfrm_if *xi, struct xfrm_if_parms *p) 712 { 713 struct net *net = xi->net; 714 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id); 715 int err; 716 717 xfrmi_unlink(xfrmn, xi); 718 synchronize_net(); 719 err = xfrmi_change(xi, p); 720 xfrmi_link(xfrmn, xi); 721 netdev_state_change(xi->dev); 722 return err; 723 } 724 725 static int xfrmi_get_iflink(const struct net_device *dev) 726 { 727 struct xfrm_if *xi = netdev_priv(dev); 728 729 return READ_ONCE(xi->p.link); 730 } 731 732 static const struct net_device_ops xfrmi_netdev_ops = { 733 .ndo_init = xfrmi_dev_init, 734 .ndo_uninit = xfrmi_dev_uninit, 735 .ndo_start_xmit = xfrmi_xmit, 736 .ndo_get_stats64 = dev_get_tstats64, 737 .ndo_get_iflink = xfrmi_get_iflink, 738 }; 739 740 static void xfrmi_dev_setup(struct net_device *dev) 741 { 742 dev->netdev_ops = &xfrmi_netdev_ops; 743 dev->header_ops = &ip_tunnel_header_ops; 744 dev->type = ARPHRD_NONE; 745 dev->mtu = ETH_DATA_LEN; 746 dev->min_mtu = ETH_MIN_MTU; 747 dev->max_mtu = IP_MAX_MTU; 748 dev->flags = IFF_NOARP; 749 dev->needs_free_netdev = true; 750 dev->priv_destructor = xfrmi_dev_free; 751 dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS; 752 netif_keep_dst(dev); 753 754 eth_broadcast_addr(dev->broadcast); 755 } 756 757 #define XFRMI_FEATURES (NETIF_F_SG | \ 758 NETIF_F_FRAGLIST | \ 759 NETIF_F_GSO_SOFTWARE | \ 760 NETIF_F_HW_CSUM) 761 762 static int xfrmi_dev_init(struct net_device *dev) 763 { 764 struct xfrm_if *xi = netdev_priv(dev); 765 struct net_device *phydev = __dev_get_by_index(xi->net, xi->p.link); 766 int err; 767 768 err = gro_cells_init(&xi->gro_cells, dev); 769 if (err) 770 return err; 771 772 dev->features |= NETIF_F_LLTX; 773 dev->features |= XFRMI_FEATURES; 774 dev->hw_features |= XFRMI_FEATURES; 775 776 if (phydev) { 777 dev->needed_headroom = phydev->needed_headroom; 778 dev->needed_tailroom = phydev->needed_tailroom; 779 780 if (is_zero_ether_addr(dev->dev_addr)) 781 eth_hw_addr_inherit(dev, phydev); 782 if (is_zero_ether_addr(dev->broadcast)) 783 memcpy(dev->broadcast, phydev->broadcast, 784 dev->addr_len); 785 } else { 786 eth_hw_addr_random(dev); 787 eth_broadcast_addr(dev->broadcast); 788 } 789 790 return 0; 791 } 792 793 static int xfrmi_validate(struct nlattr *tb[], struct nlattr *data[], 794 struct netlink_ext_ack *extack) 795 { 796 return 0; 797 } 798 799 static void xfrmi_netlink_parms(struct nlattr *data[], 800 struct xfrm_if_parms *parms) 801 { 802 memset(parms, 0, sizeof(*parms)); 803 804 if (!data) 805 return; 806 807 if (data[IFLA_XFRM_LINK]) 808 parms->link = nla_get_u32(data[IFLA_XFRM_LINK]); 809 810 if (data[IFLA_XFRM_IF_ID]) 811 parms->if_id = nla_get_u32(data[IFLA_XFRM_IF_ID]); 812 813 if (data[IFLA_XFRM_COLLECT_METADATA]) 814 parms->collect_md = true; 815 } 816 817 static int xfrmi_newlink(struct net *src_net, struct net_device *dev, 818 struct nlattr *tb[], struct nlattr *data[], 819 struct netlink_ext_ack *extack) 820 { 821 struct net *net = dev_net(dev); 822 struct xfrm_if_parms p = {}; 823 struct xfrm_if *xi; 824 int err; 825 826 xfrmi_netlink_parms(data, &p); 827 if (p.collect_md) { 828 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id); 829 830 if (p.link || p.if_id) { 831 NL_SET_ERR_MSG(extack, "link and if_id must be zero"); 832 return -EINVAL; 833 } 834 835 if (rtnl_dereference(xfrmn->collect_md_xfrmi)) 836 return -EEXIST; 837 838 } else { 839 if (!p.if_id) { 840 NL_SET_ERR_MSG(extack, "if_id must be non zero"); 841 return -EINVAL; 842 } 843 844 xi = xfrmi_locate(net, &p); 845 if (xi) 846 return -EEXIST; 847 } 848 849 xi = netdev_priv(dev); 850 xi->p = p; 851 xi->net = net; 852 xi->dev = dev; 853 854 err = xfrmi_create(dev); 855 return err; 856 } 857 858 static void xfrmi_dellink(struct net_device *dev, struct list_head *head) 859 { 860 unregister_netdevice_queue(dev, head); 861 } 862 863 static int xfrmi_changelink(struct net_device *dev, struct nlattr *tb[], 864 struct nlattr *data[], 865 struct netlink_ext_ack *extack) 866 { 867 struct xfrm_if *xi = netdev_priv(dev); 868 struct net *net = xi->net; 869 struct xfrm_if_parms p = {}; 870 871 xfrmi_netlink_parms(data, &p); 872 if (!p.if_id) { 873 NL_SET_ERR_MSG(extack, "if_id must be non zero"); 874 return -EINVAL; 875 } 876 877 if (p.collect_md) { 878 NL_SET_ERR_MSG(extack, "collect_md can't be changed"); 879 return -EINVAL; 880 } 881 882 xi = xfrmi_locate(net, &p); 883 if (!xi) { 884 xi = netdev_priv(dev); 885 } else { 886 if (xi->dev != dev) 887 return -EEXIST; 888 if (xi->p.collect_md) { 889 NL_SET_ERR_MSG(extack, 890 "device can't be changed to collect_md"); 891 return -EINVAL; 892 } 893 } 894 895 return xfrmi_update(xi, &p); 896 } 897 898 static size_t xfrmi_get_size(const struct net_device *dev) 899 { 900 return 901 /* IFLA_XFRM_LINK */ 902 nla_total_size(4) + 903 /* IFLA_XFRM_IF_ID */ 904 nla_total_size(4) + 905 /* IFLA_XFRM_COLLECT_METADATA */ 906 nla_total_size(0) + 907 0; 908 } 909 910 static int xfrmi_fill_info(struct sk_buff *skb, const struct net_device *dev) 911 { 912 struct xfrm_if *xi = netdev_priv(dev); 913 struct xfrm_if_parms *parm = &xi->p; 914 915 if (nla_put_u32(skb, IFLA_XFRM_LINK, parm->link) || 916 nla_put_u32(skb, IFLA_XFRM_IF_ID, parm->if_id) || 917 (xi->p.collect_md && nla_put_flag(skb, IFLA_XFRM_COLLECT_METADATA))) 918 goto nla_put_failure; 919 return 0; 920 921 nla_put_failure: 922 return -EMSGSIZE; 923 } 924 925 static struct net *xfrmi_get_link_net(const struct net_device *dev) 926 { 927 struct xfrm_if *xi = netdev_priv(dev); 928 929 return xi->net; 930 } 931 932 static const struct nla_policy xfrmi_policy[IFLA_XFRM_MAX + 1] = { 933 [IFLA_XFRM_UNSPEC] = { .strict_start_type = IFLA_XFRM_COLLECT_METADATA }, 934 [IFLA_XFRM_LINK] = { .type = NLA_U32 }, 935 [IFLA_XFRM_IF_ID] = { .type = NLA_U32 }, 936 [IFLA_XFRM_COLLECT_METADATA] = { .type = NLA_FLAG }, 937 }; 938 939 static struct rtnl_link_ops xfrmi_link_ops __read_mostly = { 940 .kind = "xfrm", 941 .maxtype = IFLA_XFRM_MAX, 942 .policy = xfrmi_policy, 943 .priv_size = sizeof(struct xfrm_if), 944 .setup = xfrmi_dev_setup, 945 .validate = xfrmi_validate, 946 .newlink = xfrmi_newlink, 947 .dellink = xfrmi_dellink, 948 .changelink = xfrmi_changelink, 949 .get_size = xfrmi_get_size, 950 .fill_info = xfrmi_fill_info, 951 .get_link_net = xfrmi_get_link_net, 952 }; 953 954 static void __net_exit xfrmi_exit_batch_rtnl(struct list_head *net_exit_list, 955 struct list_head *dev_to_kill) 956 { 957 struct net *net; 958 959 ASSERT_RTNL(); 960 list_for_each_entry(net, net_exit_list, exit_list) { 961 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id); 962 struct xfrm_if __rcu **xip; 963 struct xfrm_if *xi; 964 int i; 965 966 for (i = 0; i < XFRMI_HASH_SIZE; i++) { 967 for (xip = &xfrmn->xfrmi[i]; 968 (xi = rtnl_dereference(*xip)) != NULL; 969 xip = &xi->next) 970 unregister_netdevice_queue(xi->dev, dev_to_kill); 971 } 972 xi = rtnl_dereference(xfrmn->collect_md_xfrmi); 973 if (xi) 974 unregister_netdevice_queue(xi->dev, dev_to_kill); 975 } 976 } 977 978 static struct pernet_operations xfrmi_net_ops = { 979 .exit_batch_rtnl = xfrmi_exit_batch_rtnl, 980 .id = &xfrmi_net_id, 981 .size = sizeof(struct xfrmi_net), 982 }; 983 984 static struct xfrm6_protocol xfrmi_esp6_protocol __read_mostly = { 985 .handler = xfrmi6_rcv, 986 .input_handler = xfrmi6_input, 987 .cb_handler = xfrmi_rcv_cb, 988 .err_handler = xfrmi6_err, 989 .priority = 10, 990 }; 991 992 static struct xfrm6_protocol xfrmi_ah6_protocol __read_mostly = { 993 .handler = xfrm6_rcv, 994 .input_handler = xfrm_input, 995 .cb_handler = xfrmi_rcv_cb, 996 .err_handler = xfrmi6_err, 997 .priority = 10, 998 }; 999 1000 static struct xfrm6_protocol xfrmi_ipcomp6_protocol __read_mostly = { 1001 .handler = xfrm6_rcv, 1002 .input_handler = xfrm_input, 1003 .cb_handler = xfrmi_rcv_cb, 1004 .err_handler = xfrmi6_err, 1005 .priority = 10, 1006 }; 1007 1008 #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL) 1009 static int xfrmi6_rcv_tunnel(struct sk_buff *skb) 1010 { 1011 const xfrm_address_t *saddr; 1012 __be32 spi; 1013 1014 saddr = (const xfrm_address_t *)&ipv6_hdr(skb)->saddr; 1015 spi = xfrm6_tunnel_spi_lookup(dev_net(skb->dev), saddr); 1016 1017 return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi, NULL); 1018 } 1019 1020 static struct xfrm6_tunnel xfrmi_ipv6_handler __read_mostly = { 1021 .handler = xfrmi6_rcv_tunnel, 1022 .cb_handler = xfrmi_rcv_cb, 1023 .err_handler = xfrmi6_err, 1024 .priority = 2, 1025 }; 1026 1027 static struct xfrm6_tunnel xfrmi_ip6ip_handler __read_mostly = { 1028 .handler = xfrmi6_rcv_tunnel, 1029 .cb_handler = xfrmi_rcv_cb, 1030 .err_handler = xfrmi6_err, 1031 .priority = 2, 1032 }; 1033 #endif 1034 1035 static struct xfrm4_protocol xfrmi_esp4_protocol __read_mostly = { 1036 .handler = xfrmi4_rcv, 1037 .input_handler = xfrmi4_input, 1038 .cb_handler = xfrmi_rcv_cb, 1039 .err_handler = xfrmi4_err, 1040 .priority = 10, 1041 }; 1042 1043 static struct xfrm4_protocol xfrmi_ah4_protocol __read_mostly = { 1044 .handler = xfrm4_rcv, 1045 .input_handler = xfrm_input, 1046 .cb_handler = xfrmi_rcv_cb, 1047 .err_handler = xfrmi4_err, 1048 .priority = 10, 1049 }; 1050 1051 static struct xfrm4_protocol xfrmi_ipcomp4_protocol __read_mostly = { 1052 .handler = xfrm4_rcv, 1053 .input_handler = xfrm_input, 1054 .cb_handler = xfrmi_rcv_cb, 1055 .err_handler = xfrmi4_err, 1056 .priority = 10, 1057 }; 1058 1059 #if IS_REACHABLE(CONFIG_INET_XFRM_TUNNEL) 1060 static int xfrmi4_rcv_tunnel(struct sk_buff *skb) 1061 { 1062 return xfrm4_rcv_spi(skb, IPPROTO_IPIP, ip_hdr(skb)->saddr); 1063 } 1064 1065 static struct xfrm_tunnel xfrmi_ipip_handler __read_mostly = { 1066 .handler = xfrmi4_rcv_tunnel, 1067 .cb_handler = xfrmi_rcv_cb, 1068 .err_handler = xfrmi4_err, 1069 .priority = 3, 1070 }; 1071 1072 static struct xfrm_tunnel xfrmi_ipip6_handler __read_mostly = { 1073 .handler = xfrmi4_rcv_tunnel, 1074 .cb_handler = xfrmi_rcv_cb, 1075 .err_handler = xfrmi4_err, 1076 .priority = 2, 1077 }; 1078 #endif 1079 1080 static int __init xfrmi4_init(void) 1081 { 1082 int err; 1083 1084 err = xfrm4_protocol_register(&xfrmi_esp4_protocol, IPPROTO_ESP); 1085 if (err < 0) 1086 goto xfrm_proto_esp_failed; 1087 err = xfrm4_protocol_register(&xfrmi_ah4_protocol, IPPROTO_AH); 1088 if (err < 0) 1089 goto xfrm_proto_ah_failed; 1090 err = xfrm4_protocol_register(&xfrmi_ipcomp4_protocol, IPPROTO_COMP); 1091 if (err < 0) 1092 goto xfrm_proto_comp_failed; 1093 #if IS_REACHABLE(CONFIG_INET_XFRM_TUNNEL) 1094 err = xfrm4_tunnel_register(&xfrmi_ipip_handler, AF_INET); 1095 if (err < 0) 1096 goto xfrm_tunnel_ipip_failed; 1097 err = xfrm4_tunnel_register(&xfrmi_ipip6_handler, AF_INET6); 1098 if (err < 0) 1099 goto xfrm_tunnel_ipip6_failed; 1100 #endif 1101 1102 return 0; 1103 1104 #if IS_REACHABLE(CONFIG_INET_XFRM_TUNNEL) 1105 xfrm_tunnel_ipip6_failed: 1106 xfrm4_tunnel_deregister(&xfrmi_ipip_handler, AF_INET); 1107 xfrm_tunnel_ipip_failed: 1108 xfrm4_protocol_deregister(&xfrmi_ipcomp4_protocol, IPPROTO_COMP); 1109 #endif 1110 xfrm_proto_comp_failed: 1111 xfrm4_protocol_deregister(&xfrmi_ah4_protocol, IPPROTO_AH); 1112 xfrm_proto_ah_failed: 1113 xfrm4_protocol_deregister(&xfrmi_esp4_protocol, IPPROTO_ESP); 1114 xfrm_proto_esp_failed: 1115 return err; 1116 } 1117 1118 static void xfrmi4_fini(void) 1119 { 1120 #if IS_REACHABLE(CONFIG_INET_XFRM_TUNNEL) 1121 xfrm4_tunnel_deregister(&xfrmi_ipip6_handler, AF_INET6); 1122 xfrm4_tunnel_deregister(&xfrmi_ipip_handler, AF_INET); 1123 #endif 1124 xfrm4_protocol_deregister(&xfrmi_ipcomp4_protocol, IPPROTO_COMP); 1125 xfrm4_protocol_deregister(&xfrmi_ah4_protocol, IPPROTO_AH); 1126 xfrm4_protocol_deregister(&xfrmi_esp4_protocol, IPPROTO_ESP); 1127 } 1128 1129 static int __init xfrmi6_init(void) 1130 { 1131 int err; 1132 1133 err = xfrm6_protocol_register(&xfrmi_esp6_protocol, IPPROTO_ESP); 1134 if (err < 0) 1135 goto xfrm_proto_esp_failed; 1136 err = xfrm6_protocol_register(&xfrmi_ah6_protocol, IPPROTO_AH); 1137 if (err < 0) 1138 goto xfrm_proto_ah_failed; 1139 err = xfrm6_protocol_register(&xfrmi_ipcomp6_protocol, IPPROTO_COMP); 1140 if (err < 0) 1141 goto xfrm_proto_comp_failed; 1142 #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL) 1143 err = xfrm6_tunnel_register(&xfrmi_ipv6_handler, AF_INET6); 1144 if (err < 0) 1145 goto xfrm_tunnel_ipv6_failed; 1146 err = xfrm6_tunnel_register(&xfrmi_ip6ip_handler, AF_INET); 1147 if (err < 0) 1148 goto xfrm_tunnel_ip6ip_failed; 1149 #endif 1150 1151 return 0; 1152 1153 #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL) 1154 xfrm_tunnel_ip6ip_failed: 1155 xfrm6_tunnel_deregister(&xfrmi_ipv6_handler, AF_INET6); 1156 xfrm_tunnel_ipv6_failed: 1157 xfrm6_protocol_deregister(&xfrmi_ipcomp6_protocol, IPPROTO_COMP); 1158 #endif 1159 xfrm_proto_comp_failed: 1160 xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH); 1161 xfrm_proto_ah_failed: 1162 xfrm6_protocol_deregister(&xfrmi_esp6_protocol, IPPROTO_ESP); 1163 xfrm_proto_esp_failed: 1164 return err; 1165 } 1166 1167 static void xfrmi6_fini(void) 1168 { 1169 #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL) 1170 xfrm6_tunnel_deregister(&xfrmi_ip6ip_handler, AF_INET); 1171 xfrm6_tunnel_deregister(&xfrmi_ipv6_handler, AF_INET6); 1172 #endif 1173 xfrm6_protocol_deregister(&xfrmi_ipcomp6_protocol, IPPROTO_COMP); 1174 xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH); 1175 xfrm6_protocol_deregister(&xfrmi_esp6_protocol, IPPROTO_ESP); 1176 } 1177 1178 static const struct xfrm_if_cb xfrm_if_cb = { 1179 .decode_session = xfrmi_decode_session, 1180 }; 1181 1182 static int __init xfrmi_init(void) 1183 { 1184 const char *msg; 1185 int err; 1186 1187 pr_info("IPsec XFRM device driver\n"); 1188 1189 msg = "tunnel device"; 1190 err = register_pernet_device(&xfrmi_net_ops); 1191 if (err < 0) 1192 goto pernet_dev_failed; 1193 1194 msg = "xfrm4 protocols"; 1195 err = xfrmi4_init(); 1196 if (err < 0) 1197 goto xfrmi4_failed; 1198 1199 msg = "xfrm6 protocols"; 1200 err = xfrmi6_init(); 1201 if (err < 0) 1202 goto xfrmi6_failed; 1203 1204 1205 msg = "netlink interface"; 1206 err = rtnl_link_register(&xfrmi_link_ops); 1207 if (err < 0) 1208 goto rtnl_link_failed; 1209 1210 err = register_xfrm_interface_bpf(); 1211 if (err < 0) 1212 goto kfunc_failed; 1213 1214 lwtunnel_encap_add_ops(&xfrmi_encap_ops, LWTUNNEL_ENCAP_XFRM); 1215 1216 xfrm_if_register_cb(&xfrm_if_cb); 1217 1218 return err; 1219 1220 kfunc_failed: 1221 rtnl_link_unregister(&xfrmi_link_ops); 1222 rtnl_link_failed: 1223 xfrmi6_fini(); 1224 xfrmi6_failed: 1225 xfrmi4_fini(); 1226 xfrmi4_failed: 1227 unregister_pernet_device(&xfrmi_net_ops); 1228 pernet_dev_failed: 1229 pr_err("xfrmi init: failed to register %s\n", msg); 1230 return err; 1231 } 1232 1233 static void __exit xfrmi_fini(void) 1234 { 1235 xfrm_if_unregister_cb(); 1236 lwtunnel_encap_del_ops(&xfrmi_encap_ops, LWTUNNEL_ENCAP_XFRM); 1237 rtnl_link_unregister(&xfrmi_link_ops); 1238 xfrmi4_fini(); 1239 xfrmi6_fini(); 1240 unregister_pernet_device(&xfrmi_net_ops); 1241 } 1242 1243 module_init(xfrmi_init); 1244 module_exit(xfrmi_fini); 1245 MODULE_LICENSE("GPL"); 1246 MODULE_ALIAS_RTNL_LINK("xfrm"); 1247 MODULE_ALIAS_NETDEV("xfrm0"); 1248 MODULE_AUTHOR("Steffen Klassert"); 1249 MODULE_DESCRIPTION("XFRM virtual interface"); 1250