/* * Copyright (C)2003,2004 USAGI/WIDE Project * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * Authors Mitsuru KANDA <mk@linux-ipv6.org> * YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> * * Based on net/ipv4/xfrm4_tunnel.c * */ #include <linux/module.h> #include <linux/xfrm.h> #include <linux/list.h> #include <net/ip.h> #include <net/xfrm.h> #include <net/ipv6.h> #include <linux/ipv6.h> #include <linux/icmpv6.h> #include <linux/mutex.h> /* * xfrm_tunnel_spi things are for allocating unique id ("spi") * per xfrm_address_t. */ struct xfrm6_tunnel_spi { struct hlist_node list_byaddr; struct hlist_node list_byspi; xfrm_address_t addr; u32 spi; atomic_t refcnt; }; static DEFINE_RWLOCK(xfrm6_tunnel_spi_lock); static u32 xfrm6_tunnel_spi; #define XFRM6_TUNNEL_SPI_MIN 1 #define XFRM6_TUNNEL_SPI_MAX 0xffffffff static struct kmem_cache *xfrm6_tunnel_spi_kmem __read_mostly; #define XFRM6_TUNNEL_SPI_BYADDR_HSIZE 256 #define XFRM6_TUNNEL_SPI_BYSPI_HSIZE 256 static struct hlist_head xfrm6_tunnel_spi_byaddr[XFRM6_TUNNEL_SPI_BYADDR_HSIZE]; static struct hlist_head xfrm6_tunnel_spi_byspi[XFRM6_TUNNEL_SPI_BYSPI_HSIZE]; static inline unsigned xfrm6_tunnel_spi_hash_byaddr(xfrm_address_t *addr) { unsigned h; h = (__force u32)(addr->a6[0] ^ addr->a6[1] ^ addr->a6[2] ^ addr->a6[3]); h ^= h >> 16; h ^= h >> 8; h &= XFRM6_TUNNEL_SPI_BYADDR_HSIZE - 1; return h; } static inline unsigned xfrm6_tunnel_spi_hash_byspi(u32 spi) { return spi % XFRM6_TUNNEL_SPI_BYSPI_HSIZE; } static int xfrm6_tunnel_spi_init(void) { int i; xfrm6_tunnel_spi = 0; xfrm6_tunnel_spi_kmem = kmem_cache_create("xfrm6_tunnel_spi", sizeof(struct xfrm6_tunnel_spi), 0, SLAB_HWCACHE_ALIGN, NULL); if (!xfrm6_tunnel_spi_kmem) return -ENOMEM; for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++) INIT_HLIST_HEAD(&xfrm6_tunnel_spi_byaddr[i]); for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++) INIT_HLIST_HEAD(&xfrm6_tunnel_spi_byspi[i]); return 0; } static void xfrm6_tunnel_spi_fini(void) { int i; for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++) { if (!hlist_empty(&xfrm6_tunnel_spi_byaddr[i])) return; } for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++) { if (!hlist_empty(&xfrm6_tunnel_spi_byspi[i])) return; } kmem_cache_destroy(xfrm6_tunnel_spi_kmem); xfrm6_tunnel_spi_kmem = NULL; } static struct xfrm6_tunnel_spi *__xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr) { struct xfrm6_tunnel_spi *x6spi; struct hlist_node *pos; hlist_for_each_entry(x6spi, pos, &xfrm6_tunnel_spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)], list_byaddr) { if (memcmp(&x6spi->addr, saddr, sizeof(x6spi->addr)) == 0) return x6spi; } return NULL; } __be32 xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr) { struct xfrm6_tunnel_spi *x6spi; u32 spi; read_lock_bh(&xfrm6_tunnel_spi_lock); x6spi = __xfrm6_tunnel_spi_lookup(saddr); spi = x6spi ? x6spi->spi : 0; read_unlock_bh(&xfrm6_tunnel_spi_lock); return htonl(spi); } EXPORT_SYMBOL(xfrm6_tunnel_spi_lookup); static int __xfrm6_tunnel_spi_check(u32 spi) { struct xfrm6_tunnel_spi *x6spi; int index = xfrm6_tunnel_spi_hash_byspi(spi); struct hlist_node *pos; hlist_for_each_entry(x6spi, pos, &xfrm6_tunnel_spi_byspi[index], list_byspi) { if (x6spi->spi == spi) return -1; } return index; } static u32 __xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr) { u32 spi; struct xfrm6_tunnel_spi *x6spi; int index; if (xfrm6_tunnel_spi < XFRM6_TUNNEL_SPI_MIN || xfrm6_tunnel_spi >= XFRM6_TUNNEL_SPI_MAX) xfrm6_tunnel_spi = XFRM6_TUNNEL_SPI_MIN; else xfrm6_tunnel_spi++; for (spi = xfrm6_tunnel_spi; spi <= XFRM6_TUNNEL_SPI_MAX; spi++) { index = __xfrm6_tunnel_spi_check(spi); if (index >= 0) goto alloc_spi; } for (spi = XFRM6_TUNNEL_SPI_MIN; spi < xfrm6_tunnel_spi; spi++) { index = __xfrm6_tunnel_spi_check(spi); if (index >= 0) goto alloc_spi; } spi = 0; goto out; alloc_spi: xfrm6_tunnel_spi = spi; x6spi = kmem_cache_alloc(xfrm6_tunnel_spi_kmem, GFP_ATOMIC); if (!x6spi) goto out; memcpy(&x6spi->addr, saddr, sizeof(x6spi->addr)); x6spi->spi = spi; atomic_set(&x6spi->refcnt, 1); hlist_add_head(&x6spi->list_byspi, &xfrm6_tunnel_spi_byspi[index]); index = xfrm6_tunnel_spi_hash_byaddr(saddr); hlist_add_head(&x6spi->list_byaddr, &xfrm6_tunnel_spi_byaddr[index]); out: return spi; } __be32 xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr) { struct xfrm6_tunnel_spi *x6spi; u32 spi; write_lock_bh(&xfrm6_tunnel_spi_lock); x6spi = __xfrm6_tunnel_spi_lookup(saddr); if (x6spi) { atomic_inc(&x6spi->refcnt); spi = x6spi->spi; } else spi = __xfrm6_tunnel_alloc_spi(saddr); write_unlock_bh(&xfrm6_tunnel_spi_lock); return htonl(spi); } EXPORT_SYMBOL(xfrm6_tunnel_alloc_spi); void xfrm6_tunnel_free_spi(xfrm_address_t *saddr) { struct xfrm6_tunnel_spi *x6spi; struct hlist_node *pos, *n; write_lock_bh(&xfrm6_tunnel_spi_lock); hlist_for_each_entry_safe(x6spi, pos, n, &xfrm6_tunnel_spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)], list_byaddr) { if (memcmp(&x6spi->addr, saddr, sizeof(x6spi->addr)) == 0) { if (atomic_dec_and_test(&x6spi->refcnt)) { hlist_del(&x6spi->list_byaddr); hlist_del(&x6spi->list_byspi); kmem_cache_free(xfrm6_tunnel_spi_kmem, x6spi); break; } } } write_unlock_bh(&xfrm6_tunnel_spi_lock); } EXPORT_SYMBOL(xfrm6_tunnel_free_spi); static int xfrm6_tunnel_output(struct xfrm_state *x, struct sk_buff *skb) { skb_push(skb, -skb_network_offset(skb)); return 0; } static int xfrm6_tunnel_input(struct xfrm_state *x, struct sk_buff *skb) { return skb_network_header(skb)[IP6CB(skb)->nhoff]; } static int xfrm6_tunnel_rcv(struct sk_buff *skb) { struct ipv6hdr *iph = ipv6_hdr(skb); __be32 spi; spi = xfrm6_tunnel_spi_lookup((xfrm_address_t *)&iph->saddr); return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi) > 0 ? : 0; } static int xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt, int type, int code, int offset, __be32 info) { /* xfrm6_tunnel native err handling */ switch (type) { case ICMPV6_DEST_UNREACH: switch (code) { case ICMPV6_NOROUTE: case ICMPV6_ADM_PROHIBITED: case ICMPV6_NOT_NEIGHBOUR: case ICMPV6_ADDR_UNREACH: case ICMPV6_PORT_UNREACH: default: break; } break; case ICMPV6_PKT_TOOBIG: break; case ICMPV6_TIME_EXCEED: switch (code) { case ICMPV6_EXC_HOPLIMIT: break; case ICMPV6_EXC_FRAGTIME: default: break; } break; case ICMPV6_PARAMPROB: switch (code) { case ICMPV6_HDR_FIELD: break; case ICMPV6_UNK_NEXTHDR: break; case ICMPV6_UNK_OPTION: break; } break; default: break; } return 0; } static int xfrm6_tunnel_init_state(struct xfrm_state *x) { if (x->props.mode != XFRM_MODE_TUNNEL) return -EINVAL; if (x->encap) return -EINVAL; x->props.header_len = sizeof(struct ipv6hdr); return 0; } static void xfrm6_tunnel_destroy(struct xfrm_state *x) { xfrm6_tunnel_free_spi((xfrm_address_t *)&x->props.saddr); } static const struct xfrm_type xfrm6_tunnel_type = { .description = "IP6IP6", .owner = THIS_MODULE, .proto = IPPROTO_IPV6, .init_state = xfrm6_tunnel_init_state, .destructor = xfrm6_tunnel_destroy, .input = xfrm6_tunnel_input, .output = xfrm6_tunnel_output, }; static struct xfrm6_tunnel xfrm6_tunnel_handler = { .handler = xfrm6_tunnel_rcv, .err_handler = xfrm6_tunnel_err, .priority = 2, }; static struct xfrm6_tunnel xfrm46_tunnel_handler = { .handler = xfrm6_tunnel_rcv, .err_handler = xfrm6_tunnel_err, .priority = 2, }; static int __init xfrm6_tunnel_init(void) { if (xfrm_register_type(&xfrm6_tunnel_type, AF_INET6) < 0) return -EAGAIN; if (xfrm6_tunnel_register(&xfrm6_tunnel_handler, AF_INET6)) { xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6); return -EAGAIN; } if (xfrm6_tunnel_register(&xfrm46_tunnel_handler, AF_INET)) { xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6); xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6); return -EAGAIN; } if (xfrm6_tunnel_spi_init() < 0) { xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET); xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6); xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6); return -EAGAIN; } return 0; } static void __exit xfrm6_tunnel_fini(void) { xfrm6_tunnel_spi_fini(); xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET); xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6); xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6); } module_init(xfrm6_tunnel_init); module_exit(xfrm6_tunnel_fini); MODULE_LICENSE("GPL"); MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_IPV6);