/* * 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/config.h> #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 <net/protocol.h> #include <linux/ipv6.h> #include <linux/icmpv6.h> #include <linux/mutex.h> #ifdef CONFIG_IPV6_XFRM6_TUNNEL_DEBUG # define X6TDEBUG 3 #else # define X6TDEBUG 1 #endif #define X6TPRINTK(fmt, args...) printk(fmt, ## args) #define X6TNOPRINTK(fmt, args...) do { ; } while(0) #if X6TDEBUG >= 1 # define X6TPRINTK1 X6TPRINTK #else # define X6TPRINTK1 X6TNOPRINTK #endif #if X6TDEBUG >= 3 # define X6TPRINTK3 X6TPRINTK #else # define X6TPRINTK3 X6TNOPRINTK #endif /* * 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; #ifdef XFRM6_TUNNEL_SPI_MAGIC u32 magic; #endif }; #ifdef CONFIG_IPV6_XFRM6_TUNNEL_DEBUG # define XFRM6_TUNNEL_SPI_MAGIC 0xdeadbeef #endif 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 kmem_cache_t *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]; #ifdef XFRM6_TUNNEL_SPI_MAGIC static int x6spi_check_magic(const struct xfrm6_tunnel_spi *x6spi, const char *name) { if (unlikely(x6spi->magic != XFRM6_TUNNEL_SPI_MAGIC)) { X6TPRINTK3(KERN_DEBUG "%s(): x6spi object " "at %p has corrupted magic %08x " "(should be %08x)\n", name, x6spi, x6spi->magic, XFRM6_TUNNEL_SPI_MAGIC); return -1; } return 0; } #else static int inline x6spi_check_magic(const struct xfrm6_tunnel_spi *x6spi, const char *name) { return 0; } #endif #define X6SPI_CHECK_MAGIC(x6spi) x6spi_check_magic((x6spi), __FUNCTION__) static unsigned inline xfrm6_tunnel_spi_hash_byaddr(xfrm_address_t *addr) { unsigned h; X6TPRINTK3(KERN_DEBUG "%s(addr=%p)\n", __FUNCTION__, addr); h = 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; X6TPRINTK3(KERN_DEBUG "%s() = %u\n", __FUNCTION__, h); return h; } static unsigned inline xfrm6_tunnel_spi_hash_byspi(u32 spi) { return spi % XFRM6_TUNNEL_SPI_BYSPI_HSIZE; } static int xfrm6_tunnel_spi_init(void) { int i; X6TPRINTK3(KERN_DEBUG "%s()\n", __FUNCTION__); xfrm6_tunnel_spi = 0; xfrm6_tunnel_spi_kmem = kmem_cache_create("xfrm6_tunnel_spi", sizeof(struct xfrm6_tunnel_spi), 0, SLAB_HWCACHE_ALIGN, NULL, NULL); if (!xfrm6_tunnel_spi_kmem) { X6TPRINTK1(KERN_ERR "%s(): failed to allocate xfrm6_tunnel_spi_kmem\n", __FUNCTION__); 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; X6TPRINTK3(KERN_DEBUG "%s()\n", __FUNCTION__); for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++) { if (!hlist_empty(&xfrm6_tunnel_spi_byaddr[i])) goto err; } for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++) { if (!hlist_empty(&xfrm6_tunnel_spi_byspi[i])) goto err; } kmem_cache_destroy(xfrm6_tunnel_spi_kmem); xfrm6_tunnel_spi_kmem = NULL; return; err: X6TPRINTK1(KERN_ERR "%s(): table is not empty\n", __FUNCTION__); return; } static struct xfrm6_tunnel_spi *__xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr) { struct xfrm6_tunnel_spi *x6spi; struct hlist_node *pos; X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr); 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) { X6SPI_CHECK_MAGIC(x6spi); X6TPRINTK3(KERN_DEBUG "%s() = %p(%u)\n", __FUNCTION__, x6spi, x6spi->spi); return x6spi; } } X6TPRINTK3(KERN_DEBUG "%s() = NULL(0)\n", __FUNCTION__); return NULL; } u32 xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr) { struct xfrm6_tunnel_spi *x6spi; u32 spi; X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr); 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 spi; } EXPORT_SYMBOL(xfrm6_tunnel_spi_lookup); static u32 __xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr) { u32 spi; struct xfrm6_tunnel_spi *x6spi; struct hlist_node *pos; unsigned index; X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr); 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_hash_byspi(spi); hlist_for_each_entry(x6spi, pos, &xfrm6_tunnel_spi_byspi[index], list_byspi) { if (x6spi->spi == spi) goto try_next_1; } xfrm6_tunnel_spi = spi; goto alloc_spi; try_next_1:; } for (spi = XFRM6_TUNNEL_SPI_MIN; spi < xfrm6_tunnel_spi; spi++) { index = xfrm6_tunnel_spi_hash_byspi(spi); hlist_for_each_entry(x6spi, pos, &xfrm6_tunnel_spi_byspi[index], list_byspi) { if (x6spi->spi == spi) goto try_next_2; } xfrm6_tunnel_spi = spi; goto alloc_spi; try_next_2:; } spi = 0; goto out; alloc_spi: X6TPRINTK3(KERN_DEBUG "%s(): allocate new spi for " NIP6_FMT "\n", __FUNCTION__, NIP6(*(struct in6_addr *)saddr)); x6spi = kmem_cache_alloc(xfrm6_tunnel_spi_kmem, SLAB_ATOMIC); if (!x6spi) { X6TPRINTK1(KERN_ERR "%s(): kmem_cache_alloc() failed\n", __FUNCTION__); goto out; } #ifdef XFRM6_TUNNEL_SPI_MAGIC x6spi->magic = XFRM6_TUNNEL_SPI_MAGIC; #endif 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]); X6SPI_CHECK_MAGIC(x6spi); out: X6TPRINTK3(KERN_DEBUG "%s() = %u\n", __FUNCTION__, spi); return spi; } u32 xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr) { struct xfrm6_tunnel_spi *x6spi; u32 spi; X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr); 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); X6TPRINTK3(KERN_DEBUG "%s() = %u\n", __FUNCTION__, spi); return 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; X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr); 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) { X6TPRINTK3(KERN_DEBUG "%s(): x6spi object for " NIP6_FMT " found at %p\n", __FUNCTION__, NIP6(*(struct in6_addr *)saddr), x6spi); X6SPI_CHECK_MAGIC(x6spi); 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) { struct ipv6hdr *top_iph; top_iph = (struct ipv6hdr *)skb->data; top_iph->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); return 0; } static int xfrm6_tunnel_input(struct xfrm_state *x, struct xfrm_decap_state *decap, struct sk_buff *skb) { return 0; } static struct xfrm6_tunnel *xfrm6_tunnel_handler; static DEFINE_MUTEX(xfrm6_tunnel_mutex); int xfrm6_tunnel_register(struct xfrm6_tunnel *handler) { int ret; mutex_lock(&xfrm6_tunnel_mutex); ret = 0; if (xfrm6_tunnel_handler != NULL) ret = -EINVAL; if (!ret) xfrm6_tunnel_handler = handler; mutex_unlock(&xfrm6_tunnel_mutex); return ret; } EXPORT_SYMBOL(xfrm6_tunnel_register); int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler) { int ret; mutex_lock(&xfrm6_tunnel_mutex); ret = 0; if (xfrm6_tunnel_handler != handler) ret = -EINVAL; if (!ret) xfrm6_tunnel_handler = NULL; mutex_unlock(&xfrm6_tunnel_mutex); synchronize_net(); return ret; } EXPORT_SYMBOL(xfrm6_tunnel_deregister); static int xfrm6_tunnel_rcv(struct sk_buff **pskb) { struct sk_buff *skb = *pskb; struct xfrm6_tunnel *handler = xfrm6_tunnel_handler; struct ipv6hdr *iph = skb->nh.ipv6h; u32 spi; /* device-like_ip6ip6_handler() */ if (handler && handler->handler(pskb) == 0) return 0; spi = xfrm6_tunnel_spi_lookup((xfrm_address_t *)&iph->saddr); return xfrm6_rcv_spi(pskb, spi); } static void xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt, int type, int code, int offset, __u32 info) { struct xfrm6_tunnel *handler = xfrm6_tunnel_handler; /* call here first for device-like ip6ip6 err handling */ if (handler) { handler->err_handler(skb, opt, type, code, offset, info); return; } /* 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: X6TPRINTK3(KERN_DEBUG "xfrm6_tunnel: Destination Unreach.\n"); break; } break; case ICMPV6_PKT_TOOBIG: X6TPRINTK3(KERN_DEBUG "xfrm6_tunnel: Packet Too Big.\n"); break; case ICMPV6_TIME_EXCEED: switch (code) { case ICMPV6_EXC_HOPLIMIT: X6TPRINTK3(KERN_DEBUG "xfrm6_tunnel: Too small Hoplimit.\n"); 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; } static int xfrm6_tunnel_init_state(struct xfrm_state *x) { if (!x->props.mode) 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 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 inet6_protocol xfrm6_tunnel_protocol = { .handler = xfrm6_tunnel_rcv, .err_handler = xfrm6_tunnel_err, .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, }; static int __init xfrm6_tunnel_init(void) { X6TPRINTK3(KERN_DEBUG "%s()\n", __FUNCTION__); if (xfrm_register_type(&xfrm6_tunnel_type, AF_INET6) < 0) { X6TPRINTK1(KERN_ERR "xfrm6_tunnel init: can't add xfrm type\n"); return -EAGAIN; } if (inet6_add_protocol(&xfrm6_tunnel_protocol, IPPROTO_IPV6) < 0) { X6TPRINTK1(KERN_ERR "xfrm6_tunnel init(): can't add protocol\n"); xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6); return -EAGAIN; } if (xfrm6_tunnel_spi_init() < 0) { X6TPRINTK1(KERN_ERR "xfrm6_tunnel init: failed to initialize spi\n"); inet6_del_protocol(&xfrm6_tunnel_protocol, IPPROTO_IPV6); xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6); return -EAGAIN; } return 0; } static void __exit xfrm6_tunnel_fini(void) { X6TPRINTK3(KERN_DEBUG "%s()\n", __FUNCTION__); xfrm6_tunnel_spi_fini(); if (inet6_del_protocol(&xfrm6_tunnel_protocol, IPPROTO_IPV6) < 0) X6TPRINTK1(KERN_ERR "xfrm6_tunnel close: can't remove protocol\n"); if (xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6) < 0) X6TPRINTK1(KERN_ERR "xfrm6_tunnel close: can't remove xfrm type\n"); } module_init(xfrm6_tunnel_init); module_exit(xfrm6_tunnel_fini); MODULE_LICENSE("GPL");