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 free_percpu(dev->tstats); 244 } 245 246 static int xfrmi_create(struct net_device *dev) 247 { 248 struct xfrm_if *xi = netdev_priv(dev); 249 struct net *net = dev_net(dev); 250 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id); 251 int err; 252 253 dev->rtnl_link_ops = &xfrmi_link_ops; 254 err = register_netdevice(dev); 255 if (err < 0) 256 goto out; 257 258 if (xi->p.collect_md) 259 rcu_assign_pointer(xfrmn->collect_md_xfrmi, xi); 260 else 261 xfrmi_link(xfrmn, xi); 262 263 return 0; 264 265 out: 266 return err; 267 } 268 269 static struct xfrm_if *xfrmi_locate(struct net *net, struct xfrm_if_parms *p) 270 { 271 struct xfrm_if __rcu **xip; 272 struct xfrm_if *xi; 273 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id); 274 275 for (xip = &xfrmn->xfrmi[xfrmi_hash(p->if_id)]; 276 (xi = rtnl_dereference(*xip)) != NULL; 277 xip = &xi->next) 278 if (xi->p.if_id == p->if_id) 279 return xi; 280 281 return NULL; 282 } 283 284 static void xfrmi_dev_uninit(struct net_device *dev) 285 { 286 struct xfrm_if *xi = netdev_priv(dev); 287 struct xfrmi_net *xfrmn = net_generic(xi->net, xfrmi_net_id); 288 289 if (xi->p.collect_md) 290 RCU_INIT_POINTER(xfrmn->collect_md_xfrmi, NULL); 291 else 292 xfrmi_unlink(xfrmn, xi); 293 } 294 295 static void xfrmi_scrub_packet(struct sk_buff *skb, bool xnet) 296 { 297 skb_clear_tstamp(skb); 298 skb->pkt_type = PACKET_HOST; 299 skb->skb_iif = 0; 300 skb->ignore_df = 0; 301 skb_dst_drop(skb); 302 nf_reset_ct(skb); 303 nf_reset_trace(skb); 304 305 if (!xnet) 306 return; 307 308 ipvs_reset(skb); 309 secpath_reset(skb); 310 skb_orphan(skb); 311 skb->mark = 0; 312 } 313 314 static int xfrmi_input(struct sk_buff *skb, int nexthdr, __be32 spi, 315 int encap_type, unsigned short family) 316 { 317 struct sec_path *sp; 318 319 sp = skb_sec_path(skb); 320 if (sp && (sp->len || sp->olen) && 321 !xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family)) 322 goto discard; 323 324 XFRM_SPI_SKB_CB(skb)->family = family; 325 if (family == AF_INET) { 326 XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr); 327 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL; 328 } else { 329 XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr); 330 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = NULL; 331 } 332 333 return xfrm_input(skb, nexthdr, spi, encap_type); 334 discard: 335 kfree_skb(skb); 336 return 0; 337 } 338 339 static int xfrmi4_rcv(struct sk_buff *skb) 340 { 341 return xfrmi_input(skb, ip_hdr(skb)->protocol, 0, 0, AF_INET); 342 } 343 344 static int xfrmi6_rcv(struct sk_buff *skb) 345 { 346 return xfrmi_input(skb, skb_network_header(skb)[IP6CB(skb)->nhoff], 347 0, 0, AF_INET6); 348 } 349 350 static int xfrmi4_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) 351 { 352 return xfrmi_input(skb, nexthdr, spi, encap_type, AF_INET); 353 } 354 355 static int xfrmi6_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) 356 { 357 return xfrmi_input(skb, nexthdr, spi, encap_type, AF_INET6); 358 } 359 360 static int xfrmi_rcv_cb(struct sk_buff *skb, int err) 361 { 362 const struct xfrm_mode *inner_mode; 363 struct net_device *dev; 364 struct xfrm_state *x; 365 struct xfrm_if *xi; 366 bool xnet; 367 int link; 368 369 if (err && !secpath_exists(skb)) 370 return 0; 371 372 x = xfrm_input_state(skb); 373 374 xi = xfrmi_lookup(xs_net(x), x); 375 if (!xi) 376 return 1; 377 378 link = skb->dev->ifindex; 379 dev = xi->dev; 380 skb->dev = dev; 381 382 if (err) { 383 DEV_STATS_INC(dev, rx_errors); 384 DEV_STATS_INC(dev, rx_dropped); 385 386 return 0; 387 } 388 389 xnet = !net_eq(xi->net, dev_net(skb->dev)); 390 391 if (xnet) { 392 inner_mode = &x->inner_mode; 393 394 if (x->sel.family == AF_UNSPEC) { 395 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol); 396 if (inner_mode == NULL) { 397 XFRM_INC_STATS(dev_net(skb->dev), 398 LINUX_MIB_XFRMINSTATEMODEERROR); 399 return -EINVAL; 400 } 401 } 402 403 if (!xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, 404 inner_mode->family)) 405 return -EPERM; 406 } 407 408 xfrmi_scrub_packet(skb, xnet); 409 if (xi->p.collect_md) { 410 struct metadata_dst *md_dst; 411 412 md_dst = metadata_dst_alloc(0, METADATA_XFRM, GFP_ATOMIC); 413 if (!md_dst) 414 return -ENOMEM; 415 416 md_dst->u.xfrm_info.if_id = x->if_id; 417 md_dst->u.xfrm_info.link = link; 418 skb_dst_set(skb, (struct dst_entry *)md_dst); 419 } 420 dev_sw_netstats_rx_add(dev, skb->len); 421 422 return 0; 423 } 424 425 static int 426 xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) 427 { 428 struct xfrm_if *xi = netdev_priv(dev); 429 struct dst_entry *dst = skb_dst(skb); 430 unsigned int length = skb->len; 431 struct net_device *tdev; 432 struct xfrm_state *x; 433 int err = -1; 434 u32 if_id; 435 int mtu; 436 437 if (xi->p.collect_md) { 438 struct xfrm_md_info *md_info = skb_xfrm_md_info(skb); 439 440 if (unlikely(!md_info)) 441 return -EINVAL; 442 443 if_id = md_info->if_id; 444 fl->flowi_oif = md_info->link; 445 if (md_info->dst_orig) { 446 struct dst_entry *tmp_dst = dst; 447 448 dst = md_info->dst_orig; 449 skb_dst_set(skb, dst); 450 md_info->dst_orig = NULL; 451 dst_release(tmp_dst); 452 } 453 } else { 454 if_id = xi->p.if_id; 455 } 456 457 dst_hold(dst); 458 dst = xfrm_lookup_with_ifid(xi->net, dst, fl, NULL, 0, if_id); 459 if (IS_ERR(dst)) { 460 err = PTR_ERR(dst); 461 dst = NULL; 462 goto tx_err_link_failure; 463 } 464 465 x = dst->xfrm; 466 if (!x) 467 goto tx_err_link_failure; 468 469 if (x->if_id != if_id) 470 goto tx_err_link_failure; 471 472 tdev = dst->dev; 473 474 if (tdev == dev) { 475 DEV_STATS_INC(dev, collisions); 476 net_warn_ratelimited("%s: Local routing loop detected!\n", 477 dev->name); 478 goto tx_err_dst_release; 479 } 480 481 mtu = dst_mtu(dst); 482 if ((!skb_is_gso(skb) && skb->len > mtu) || 483 (skb_is_gso(skb) && !skb_gso_validate_network_len(skb, mtu))) { 484 skb_dst_update_pmtu_no_confirm(skb, mtu); 485 486 if (skb->protocol == htons(ETH_P_IPV6)) { 487 if (mtu < IPV6_MIN_MTU) 488 mtu = IPV6_MIN_MTU; 489 490 if (skb->len > 1280) 491 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 492 else 493 goto xmit; 494 } else { 495 if (!(ip_hdr(skb)->frag_off & htons(IP_DF))) 496 goto xmit; 497 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 498 htonl(mtu)); 499 } 500 501 dst_release(dst); 502 return -EMSGSIZE; 503 } 504 505 xmit: 506 xfrmi_scrub_packet(skb, !net_eq(xi->net, dev_net(dev))); 507 skb_dst_set(skb, dst); 508 skb->dev = tdev; 509 510 err = dst_output(xi->net, skb->sk, skb); 511 if (net_xmit_eval(err) == 0) { 512 dev_sw_netstats_tx_add(dev, 1, length); 513 } else { 514 DEV_STATS_INC(dev, tx_errors); 515 DEV_STATS_INC(dev, tx_aborted_errors); 516 } 517 518 return 0; 519 tx_err_link_failure: 520 DEV_STATS_INC(dev, tx_carrier_errors); 521 dst_link_failure(skb); 522 tx_err_dst_release: 523 dst_release(dst); 524 return err; 525 } 526 527 static netdev_tx_t xfrmi_xmit(struct sk_buff *skb, struct net_device *dev) 528 { 529 struct xfrm_if *xi = netdev_priv(dev); 530 struct dst_entry *dst = skb_dst(skb); 531 struct flowi fl; 532 int ret; 533 534 memset(&fl, 0, sizeof(fl)); 535 536 switch (skb->protocol) { 537 case htons(ETH_P_IPV6): 538 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); 539 xfrm_decode_session(skb, &fl, AF_INET6); 540 if (!dst) { 541 fl.u.ip6.flowi6_oif = dev->ifindex; 542 fl.u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC; 543 dst = ip6_route_output(dev_net(dev), NULL, &fl.u.ip6); 544 if (dst->error) { 545 dst_release(dst); 546 DEV_STATS_INC(dev, tx_carrier_errors); 547 goto tx_err; 548 } 549 skb_dst_set(skb, dst); 550 } 551 break; 552 case htons(ETH_P_IP): 553 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 554 xfrm_decode_session(skb, &fl, AF_INET); 555 if (!dst) { 556 struct rtable *rt; 557 558 fl.u.ip4.flowi4_oif = dev->ifindex; 559 fl.u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC; 560 rt = __ip_route_output_key(dev_net(dev), &fl.u.ip4); 561 if (IS_ERR(rt)) { 562 DEV_STATS_INC(dev, tx_carrier_errors); 563 goto tx_err; 564 } 565 skb_dst_set(skb, &rt->dst); 566 } 567 break; 568 default: 569 goto tx_err; 570 } 571 572 fl.flowi_oif = xi->p.link; 573 574 ret = xfrmi_xmit2(skb, dev, &fl); 575 if (ret < 0) 576 goto tx_err; 577 578 return NETDEV_TX_OK; 579 580 tx_err: 581 DEV_STATS_INC(dev, tx_errors); 582 DEV_STATS_INC(dev, tx_dropped); 583 kfree_skb(skb); 584 return NETDEV_TX_OK; 585 } 586 587 static int xfrmi4_err(struct sk_buff *skb, u32 info) 588 { 589 const struct iphdr *iph = (const struct iphdr *)skb->data; 590 struct net *net = dev_net(skb->dev); 591 int protocol = iph->protocol; 592 struct ip_comp_hdr *ipch; 593 struct ip_esp_hdr *esph; 594 struct ip_auth_hdr *ah ; 595 struct xfrm_state *x; 596 struct xfrm_if *xi; 597 __be32 spi; 598 599 switch (protocol) { 600 case IPPROTO_ESP: 601 esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2)); 602 spi = esph->spi; 603 break; 604 case IPPROTO_AH: 605 ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2)); 606 spi = ah->spi; 607 break; 608 case IPPROTO_COMP: 609 ipch = (struct ip_comp_hdr *)(skb->data+(iph->ihl<<2)); 610 spi = htonl(ntohs(ipch->cpi)); 611 break; 612 default: 613 return 0; 614 } 615 616 switch (icmp_hdr(skb)->type) { 617 case ICMP_DEST_UNREACH: 618 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) 619 return 0; 620 break; 621 case ICMP_REDIRECT: 622 break; 623 default: 624 return 0; 625 } 626 627 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 628 spi, protocol, AF_INET); 629 if (!x) 630 return 0; 631 632 xi = xfrmi_lookup(net, x); 633 if (!xi) { 634 xfrm_state_put(x); 635 return -1; 636 } 637 638 if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) 639 ipv4_update_pmtu(skb, net, info, 0, protocol); 640 else 641 ipv4_redirect(skb, net, 0, protocol); 642 xfrm_state_put(x); 643 644 return 0; 645 } 646 647 static int xfrmi6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 648 u8 type, u8 code, int offset, __be32 info) 649 { 650 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; 651 struct net *net = dev_net(skb->dev); 652 int protocol = iph->nexthdr; 653 struct ip_comp_hdr *ipch; 654 struct ip_esp_hdr *esph; 655 struct ip_auth_hdr *ah; 656 struct xfrm_state *x; 657 struct xfrm_if *xi; 658 __be32 spi; 659 660 switch (protocol) { 661 case IPPROTO_ESP: 662 esph = (struct ip_esp_hdr *)(skb->data + offset); 663 spi = esph->spi; 664 break; 665 case IPPROTO_AH: 666 ah = (struct ip_auth_hdr *)(skb->data + offset); 667 spi = ah->spi; 668 break; 669 case IPPROTO_COMP: 670 ipch = (struct ip_comp_hdr *)(skb->data + offset); 671 spi = htonl(ntohs(ipch->cpi)); 672 break; 673 default: 674 return 0; 675 } 676 677 if (type != ICMPV6_PKT_TOOBIG && 678 type != NDISC_REDIRECT) 679 return 0; 680 681 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 682 spi, protocol, AF_INET6); 683 if (!x) 684 return 0; 685 686 xi = xfrmi_lookup(net, x); 687 if (!xi) { 688 xfrm_state_put(x); 689 return -1; 690 } 691 692 if (type == NDISC_REDIRECT) 693 ip6_redirect(skb, net, skb->dev->ifindex, 0, 694 sock_net_uid(net, NULL)); 695 else 696 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); 697 xfrm_state_put(x); 698 699 return 0; 700 } 701 702 static int xfrmi_change(struct xfrm_if *xi, const struct xfrm_if_parms *p) 703 { 704 if (xi->p.link != p->link) 705 return -EINVAL; 706 707 xi->p.if_id = p->if_id; 708 709 return 0; 710 } 711 712 static int xfrmi_update(struct xfrm_if *xi, struct xfrm_if_parms *p) 713 { 714 struct net *net = xi->net; 715 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id); 716 int err; 717 718 xfrmi_unlink(xfrmn, xi); 719 synchronize_net(); 720 err = xfrmi_change(xi, p); 721 xfrmi_link(xfrmn, xi); 722 netdev_state_change(xi->dev); 723 return err; 724 } 725 726 static int xfrmi_get_iflink(const struct net_device *dev) 727 { 728 struct xfrm_if *xi = netdev_priv(dev); 729 730 return xi->p.link; 731 } 732 733 static const struct net_device_ops xfrmi_netdev_ops = { 734 .ndo_init = xfrmi_dev_init, 735 .ndo_uninit = xfrmi_dev_uninit, 736 .ndo_start_xmit = xfrmi_xmit, 737 .ndo_get_stats64 = dev_get_tstats64, 738 .ndo_get_iflink = xfrmi_get_iflink, 739 }; 740 741 static void xfrmi_dev_setup(struct net_device *dev) 742 { 743 dev->netdev_ops = &xfrmi_netdev_ops; 744 dev->header_ops = &ip_tunnel_header_ops; 745 dev->type = ARPHRD_NONE; 746 dev->mtu = ETH_DATA_LEN; 747 dev->min_mtu = ETH_MIN_MTU; 748 dev->max_mtu = IP_MAX_MTU; 749 dev->flags = IFF_NOARP; 750 dev->needs_free_netdev = true; 751 dev->priv_destructor = xfrmi_dev_free; 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 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 769 if (!dev->tstats) 770 return -ENOMEM; 771 772 err = gro_cells_init(&xi->gro_cells, dev); 773 if (err) { 774 free_percpu(dev->tstats); 775 return err; 776 } 777 778 dev->features |= NETIF_F_LLTX; 779 dev->features |= XFRMI_FEATURES; 780 dev->hw_features |= XFRMI_FEATURES; 781 782 if (phydev) { 783 dev->needed_headroom = phydev->needed_headroom; 784 dev->needed_tailroom = phydev->needed_tailroom; 785 786 if (is_zero_ether_addr(dev->dev_addr)) 787 eth_hw_addr_inherit(dev, phydev); 788 if (is_zero_ether_addr(dev->broadcast)) 789 memcpy(dev->broadcast, phydev->broadcast, 790 dev->addr_len); 791 } else { 792 eth_hw_addr_random(dev); 793 eth_broadcast_addr(dev->broadcast); 794 } 795 796 return 0; 797 } 798 799 static int xfrmi_validate(struct nlattr *tb[], struct nlattr *data[], 800 struct netlink_ext_ack *extack) 801 { 802 return 0; 803 } 804 805 static void xfrmi_netlink_parms(struct nlattr *data[], 806 struct xfrm_if_parms *parms) 807 { 808 memset(parms, 0, sizeof(*parms)); 809 810 if (!data) 811 return; 812 813 if (data[IFLA_XFRM_LINK]) 814 parms->link = nla_get_u32(data[IFLA_XFRM_LINK]); 815 816 if (data[IFLA_XFRM_IF_ID]) 817 parms->if_id = nla_get_u32(data[IFLA_XFRM_IF_ID]); 818 819 if (data[IFLA_XFRM_COLLECT_METADATA]) 820 parms->collect_md = true; 821 } 822 823 static int xfrmi_newlink(struct net *src_net, struct net_device *dev, 824 struct nlattr *tb[], struct nlattr *data[], 825 struct netlink_ext_ack *extack) 826 { 827 struct net *net = dev_net(dev); 828 struct xfrm_if_parms p = {}; 829 struct xfrm_if *xi; 830 int err; 831 832 xfrmi_netlink_parms(data, &p); 833 if (p.collect_md) { 834 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id); 835 836 if (p.link || p.if_id) { 837 NL_SET_ERR_MSG(extack, "link and if_id must be zero"); 838 return -EINVAL; 839 } 840 841 if (rtnl_dereference(xfrmn->collect_md_xfrmi)) 842 return -EEXIST; 843 844 } else { 845 if (!p.if_id) { 846 NL_SET_ERR_MSG(extack, "if_id must be non zero"); 847 return -EINVAL; 848 } 849 850 xi = xfrmi_locate(net, &p); 851 if (xi) 852 return -EEXIST; 853 } 854 855 xi = netdev_priv(dev); 856 xi->p = p; 857 xi->net = net; 858 xi->dev = dev; 859 860 err = xfrmi_create(dev); 861 return err; 862 } 863 864 static void xfrmi_dellink(struct net_device *dev, struct list_head *head) 865 { 866 unregister_netdevice_queue(dev, head); 867 } 868 869 static int xfrmi_changelink(struct net_device *dev, struct nlattr *tb[], 870 struct nlattr *data[], 871 struct netlink_ext_ack *extack) 872 { 873 struct xfrm_if *xi = netdev_priv(dev); 874 struct net *net = xi->net; 875 struct xfrm_if_parms p = {}; 876 877 xfrmi_netlink_parms(data, &p); 878 if (!p.if_id) { 879 NL_SET_ERR_MSG(extack, "if_id must be non zero"); 880 return -EINVAL; 881 } 882 883 if (p.collect_md) { 884 NL_SET_ERR_MSG(extack, "collect_md can't be changed"); 885 return -EINVAL; 886 } 887 888 xi = xfrmi_locate(net, &p); 889 if (!xi) { 890 xi = netdev_priv(dev); 891 } else { 892 if (xi->dev != dev) 893 return -EEXIST; 894 if (xi->p.collect_md) { 895 NL_SET_ERR_MSG(extack, 896 "device can't be changed to collect_md"); 897 return -EINVAL; 898 } 899 } 900 901 return xfrmi_update(xi, &p); 902 } 903 904 static size_t xfrmi_get_size(const struct net_device *dev) 905 { 906 return 907 /* IFLA_XFRM_LINK */ 908 nla_total_size(4) + 909 /* IFLA_XFRM_IF_ID */ 910 nla_total_size(4) + 911 /* IFLA_XFRM_COLLECT_METADATA */ 912 nla_total_size(0) + 913 0; 914 } 915 916 static int xfrmi_fill_info(struct sk_buff *skb, const struct net_device *dev) 917 { 918 struct xfrm_if *xi = netdev_priv(dev); 919 struct xfrm_if_parms *parm = &xi->p; 920 921 if (nla_put_u32(skb, IFLA_XFRM_LINK, parm->link) || 922 nla_put_u32(skb, IFLA_XFRM_IF_ID, parm->if_id) || 923 (xi->p.collect_md && nla_put_flag(skb, IFLA_XFRM_COLLECT_METADATA))) 924 goto nla_put_failure; 925 return 0; 926 927 nla_put_failure: 928 return -EMSGSIZE; 929 } 930 931 static struct net *xfrmi_get_link_net(const struct net_device *dev) 932 { 933 struct xfrm_if *xi = netdev_priv(dev); 934 935 return xi->net; 936 } 937 938 static const struct nla_policy xfrmi_policy[IFLA_XFRM_MAX + 1] = { 939 [IFLA_XFRM_UNSPEC] = { .strict_start_type = IFLA_XFRM_COLLECT_METADATA }, 940 [IFLA_XFRM_LINK] = { .type = NLA_U32 }, 941 [IFLA_XFRM_IF_ID] = { .type = NLA_U32 }, 942 [IFLA_XFRM_COLLECT_METADATA] = { .type = NLA_FLAG }, 943 }; 944 945 static struct rtnl_link_ops xfrmi_link_ops __read_mostly = { 946 .kind = "xfrm", 947 .maxtype = IFLA_XFRM_MAX, 948 .policy = xfrmi_policy, 949 .priv_size = sizeof(struct xfrm_if), 950 .setup = xfrmi_dev_setup, 951 .validate = xfrmi_validate, 952 .newlink = xfrmi_newlink, 953 .dellink = xfrmi_dellink, 954 .changelink = xfrmi_changelink, 955 .get_size = xfrmi_get_size, 956 .fill_info = xfrmi_fill_info, 957 .get_link_net = xfrmi_get_link_net, 958 }; 959 960 static void __net_exit xfrmi_exit_batch_net(struct list_head *net_exit_list) 961 { 962 struct net *net; 963 LIST_HEAD(list); 964 965 rtnl_lock(); 966 list_for_each_entry(net, net_exit_list, exit_list) { 967 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id); 968 struct xfrm_if __rcu **xip; 969 struct xfrm_if *xi; 970 int i; 971 972 for (i = 0; i < XFRMI_HASH_SIZE; i++) { 973 for (xip = &xfrmn->xfrmi[i]; 974 (xi = rtnl_dereference(*xip)) != NULL; 975 xip = &xi->next) 976 unregister_netdevice_queue(xi->dev, &list); 977 } 978 xi = rtnl_dereference(xfrmn->collect_md_xfrmi); 979 if (xi) 980 unregister_netdevice_queue(xi->dev, &list); 981 } 982 unregister_netdevice_many(&list); 983 rtnl_unlock(); 984 } 985 986 static struct pernet_operations xfrmi_net_ops = { 987 .exit_batch = xfrmi_exit_batch_net, 988 .id = &xfrmi_net_id, 989 .size = sizeof(struct xfrmi_net), 990 }; 991 992 static struct xfrm6_protocol xfrmi_esp6_protocol __read_mostly = { 993 .handler = xfrmi6_rcv, 994 .input_handler = xfrmi6_input, 995 .cb_handler = xfrmi_rcv_cb, 996 .err_handler = xfrmi6_err, 997 .priority = 10, 998 }; 999 1000 static struct xfrm6_protocol xfrmi_ah6_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 static struct xfrm6_protocol xfrmi_ipcomp6_protocol __read_mostly = { 1009 .handler = xfrm6_rcv, 1010 .input_handler = xfrm_input, 1011 .cb_handler = xfrmi_rcv_cb, 1012 .err_handler = xfrmi6_err, 1013 .priority = 10, 1014 }; 1015 1016 #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL) 1017 static int xfrmi6_rcv_tunnel(struct sk_buff *skb) 1018 { 1019 const xfrm_address_t *saddr; 1020 __be32 spi; 1021 1022 saddr = (const xfrm_address_t *)&ipv6_hdr(skb)->saddr; 1023 spi = xfrm6_tunnel_spi_lookup(dev_net(skb->dev), saddr); 1024 1025 return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi, NULL); 1026 } 1027 1028 static struct xfrm6_tunnel xfrmi_ipv6_handler __read_mostly = { 1029 .handler = xfrmi6_rcv_tunnel, 1030 .cb_handler = xfrmi_rcv_cb, 1031 .err_handler = xfrmi6_err, 1032 .priority = 2, 1033 }; 1034 1035 static struct xfrm6_tunnel xfrmi_ip6ip_handler __read_mostly = { 1036 .handler = xfrmi6_rcv_tunnel, 1037 .cb_handler = xfrmi_rcv_cb, 1038 .err_handler = xfrmi6_err, 1039 .priority = 2, 1040 }; 1041 #endif 1042 1043 static struct xfrm4_protocol xfrmi_esp4_protocol __read_mostly = { 1044 .handler = xfrmi4_rcv, 1045 .input_handler = xfrmi4_input, 1046 .cb_handler = xfrmi_rcv_cb, 1047 .err_handler = xfrmi4_err, 1048 .priority = 10, 1049 }; 1050 1051 static struct xfrm4_protocol xfrmi_ah4_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 static struct xfrm4_protocol xfrmi_ipcomp4_protocol __read_mostly = { 1060 .handler = xfrm4_rcv, 1061 .input_handler = xfrm_input, 1062 .cb_handler = xfrmi_rcv_cb, 1063 .err_handler = xfrmi4_err, 1064 .priority = 10, 1065 }; 1066 1067 #if IS_REACHABLE(CONFIG_INET_XFRM_TUNNEL) 1068 static int xfrmi4_rcv_tunnel(struct sk_buff *skb) 1069 { 1070 return xfrm4_rcv_spi(skb, IPPROTO_IPIP, ip_hdr(skb)->saddr); 1071 } 1072 1073 static struct xfrm_tunnel xfrmi_ipip_handler __read_mostly = { 1074 .handler = xfrmi4_rcv_tunnel, 1075 .cb_handler = xfrmi_rcv_cb, 1076 .err_handler = xfrmi4_err, 1077 .priority = 3, 1078 }; 1079 1080 static struct xfrm_tunnel xfrmi_ipip6_handler __read_mostly = { 1081 .handler = xfrmi4_rcv_tunnel, 1082 .cb_handler = xfrmi_rcv_cb, 1083 .err_handler = xfrmi4_err, 1084 .priority = 2, 1085 }; 1086 #endif 1087 1088 static int __init xfrmi4_init(void) 1089 { 1090 int err; 1091 1092 err = xfrm4_protocol_register(&xfrmi_esp4_protocol, IPPROTO_ESP); 1093 if (err < 0) 1094 goto xfrm_proto_esp_failed; 1095 err = xfrm4_protocol_register(&xfrmi_ah4_protocol, IPPROTO_AH); 1096 if (err < 0) 1097 goto xfrm_proto_ah_failed; 1098 err = xfrm4_protocol_register(&xfrmi_ipcomp4_protocol, IPPROTO_COMP); 1099 if (err < 0) 1100 goto xfrm_proto_comp_failed; 1101 #if IS_REACHABLE(CONFIG_INET_XFRM_TUNNEL) 1102 err = xfrm4_tunnel_register(&xfrmi_ipip_handler, AF_INET); 1103 if (err < 0) 1104 goto xfrm_tunnel_ipip_failed; 1105 err = xfrm4_tunnel_register(&xfrmi_ipip6_handler, AF_INET6); 1106 if (err < 0) 1107 goto xfrm_tunnel_ipip6_failed; 1108 #endif 1109 1110 return 0; 1111 1112 #if IS_REACHABLE(CONFIG_INET_XFRM_TUNNEL) 1113 xfrm_tunnel_ipip6_failed: 1114 xfrm4_tunnel_deregister(&xfrmi_ipip_handler, AF_INET); 1115 xfrm_tunnel_ipip_failed: 1116 xfrm4_protocol_deregister(&xfrmi_ipcomp4_protocol, IPPROTO_COMP); 1117 #endif 1118 xfrm_proto_comp_failed: 1119 xfrm4_protocol_deregister(&xfrmi_ah4_protocol, IPPROTO_AH); 1120 xfrm_proto_ah_failed: 1121 xfrm4_protocol_deregister(&xfrmi_esp4_protocol, IPPROTO_ESP); 1122 xfrm_proto_esp_failed: 1123 return err; 1124 } 1125 1126 static void xfrmi4_fini(void) 1127 { 1128 #if IS_REACHABLE(CONFIG_INET_XFRM_TUNNEL) 1129 xfrm4_tunnel_deregister(&xfrmi_ipip6_handler, AF_INET6); 1130 xfrm4_tunnel_deregister(&xfrmi_ipip_handler, AF_INET); 1131 #endif 1132 xfrm4_protocol_deregister(&xfrmi_ipcomp4_protocol, IPPROTO_COMP); 1133 xfrm4_protocol_deregister(&xfrmi_ah4_protocol, IPPROTO_AH); 1134 xfrm4_protocol_deregister(&xfrmi_esp4_protocol, IPPROTO_ESP); 1135 } 1136 1137 static int __init xfrmi6_init(void) 1138 { 1139 int err; 1140 1141 err = xfrm6_protocol_register(&xfrmi_esp6_protocol, IPPROTO_ESP); 1142 if (err < 0) 1143 goto xfrm_proto_esp_failed; 1144 err = xfrm6_protocol_register(&xfrmi_ah6_protocol, IPPROTO_AH); 1145 if (err < 0) 1146 goto xfrm_proto_ah_failed; 1147 err = xfrm6_protocol_register(&xfrmi_ipcomp6_protocol, IPPROTO_COMP); 1148 if (err < 0) 1149 goto xfrm_proto_comp_failed; 1150 #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL) 1151 err = xfrm6_tunnel_register(&xfrmi_ipv6_handler, AF_INET6); 1152 if (err < 0) 1153 goto xfrm_tunnel_ipv6_failed; 1154 err = xfrm6_tunnel_register(&xfrmi_ip6ip_handler, AF_INET); 1155 if (err < 0) 1156 goto xfrm_tunnel_ip6ip_failed; 1157 #endif 1158 1159 return 0; 1160 1161 #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL) 1162 xfrm_tunnel_ip6ip_failed: 1163 xfrm6_tunnel_deregister(&xfrmi_ipv6_handler, AF_INET6); 1164 xfrm_tunnel_ipv6_failed: 1165 xfrm6_protocol_deregister(&xfrmi_ipcomp6_protocol, IPPROTO_COMP); 1166 #endif 1167 xfrm_proto_comp_failed: 1168 xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH); 1169 xfrm_proto_ah_failed: 1170 xfrm6_protocol_deregister(&xfrmi_esp6_protocol, IPPROTO_ESP); 1171 xfrm_proto_esp_failed: 1172 return err; 1173 } 1174 1175 static void xfrmi6_fini(void) 1176 { 1177 #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL) 1178 xfrm6_tunnel_deregister(&xfrmi_ip6ip_handler, AF_INET); 1179 xfrm6_tunnel_deregister(&xfrmi_ipv6_handler, AF_INET6); 1180 #endif 1181 xfrm6_protocol_deregister(&xfrmi_ipcomp6_protocol, IPPROTO_COMP); 1182 xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH); 1183 xfrm6_protocol_deregister(&xfrmi_esp6_protocol, IPPROTO_ESP); 1184 } 1185 1186 static const struct xfrm_if_cb xfrm_if_cb = { 1187 .decode_session = xfrmi_decode_session, 1188 }; 1189 1190 static int __init xfrmi_init(void) 1191 { 1192 const char *msg; 1193 int err; 1194 1195 pr_info("IPsec XFRM device driver\n"); 1196 1197 msg = "tunnel device"; 1198 err = register_pernet_device(&xfrmi_net_ops); 1199 if (err < 0) 1200 goto pernet_dev_failed; 1201 1202 msg = "xfrm4 protocols"; 1203 err = xfrmi4_init(); 1204 if (err < 0) 1205 goto xfrmi4_failed; 1206 1207 msg = "xfrm6 protocols"; 1208 err = xfrmi6_init(); 1209 if (err < 0) 1210 goto xfrmi6_failed; 1211 1212 1213 msg = "netlink interface"; 1214 err = rtnl_link_register(&xfrmi_link_ops); 1215 if (err < 0) 1216 goto rtnl_link_failed; 1217 1218 err = register_xfrm_interface_bpf(); 1219 if (err < 0) 1220 goto kfunc_failed; 1221 1222 lwtunnel_encap_add_ops(&xfrmi_encap_ops, LWTUNNEL_ENCAP_XFRM); 1223 1224 xfrm_if_register_cb(&xfrm_if_cb); 1225 1226 return err; 1227 1228 kfunc_failed: 1229 rtnl_link_unregister(&xfrmi_link_ops); 1230 rtnl_link_failed: 1231 xfrmi6_fini(); 1232 xfrmi6_failed: 1233 xfrmi4_fini(); 1234 xfrmi4_failed: 1235 unregister_pernet_device(&xfrmi_net_ops); 1236 pernet_dev_failed: 1237 pr_err("xfrmi init: failed to register %s\n", msg); 1238 return err; 1239 } 1240 1241 static void __exit xfrmi_fini(void) 1242 { 1243 xfrm_if_unregister_cb(); 1244 lwtunnel_encap_del_ops(&xfrmi_encap_ops, LWTUNNEL_ENCAP_XFRM); 1245 rtnl_link_unregister(&xfrmi_link_ops); 1246 xfrmi4_fini(); 1247 xfrmi6_fini(); 1248 unregister_pernet_device(&xfrmi_net_ops); 1249 } 1250 1251 module_init(xfrmi_init); 1252 module_exit(xfrmi_fini); 1253 MODULE_LICENSE("GPL"); 1254 MODULE_ALIAS_RTNL_LINK("xfrm"); 1255 MODULE_ALIAS_NETDEV("xfrm0"); 1256 MODULE_AUTHOR("Steffen Klassert"); 1257 MODULE_DESCRIPTION("XFRM virtual interface"); 1258