| /* |
| * IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173 |
| * |
| * Copyright (C)2003 USAGI/WIDE Project |
| * |
| * Author Mitsuru KANDA <mk@linux-ipv6.org> |
| * |
| * 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 |
| */ |
| /* |
| * [Memo] |
| * |
| * Outbound: |
| * The compression of IP datagram MUST be done before AH/ESP processing, |
| * fragmentation, and the addition of Hop-by-Hop/Routing header. |
| * |
| * Inbound: |
| * The decompression of IP datagram MUST be done after the reassembly, |
| * AH/ESP processing. |
| */ |
| #include <linux/module.h> |
| #include <net/ip.h> |
| #include <net/xfrm.h> |
| #include <net/ipcomp.h> |
| #include <linux/crypto.h> |
| #include <linux/err.h> |
| #include <linux/pfkeyv2.h> |
| #include <linux/random.h> |
| #include <linux/percpu.h> |
| #include <linux/smp.h> |
| #include <linux/list.h> |
| #include <linux/vmalloc.h> |
| #include <linux/rtnetlink.h> |
| #include <net/icmp.h> |
| #include <net/ipv6.h> |
| #include <net/protocol.h> |
| #include <linux/ipv6.h> |
| #include <linux/icmpv6.h> |
| #include <linux/mutex.h> |
| |
| static void ipcomp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, |
| int type, int code, int offset, __be32 info) |
| { |
| __be32 spi; |
| struct ipv6hdr *iph = (struct ipv6hdr*)skb->data; |
| struct ip_comp_hdr *ipcomph = |
| (struct ip_comp_hdr *)(skb->data + offset); |
| struct xfrm_state *x; |
| |
| if (type != ICMPV6_DEST_UNREACH && type != ICMPV6_PKT_TOOBIG) |
| return; |
| |
| spi = htonl(ntohs(ipcomph->cpi)); |
| x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi, IPPROTO_COMP, AF_INET6); |
| if (!x) |
| return; |
| |
| printk(KERN_DEBUG "pmtu discovery on SA IPCOMP/%08x/" NIP6_FMT "\n", |
| spi, NIP6(iph->daddr)); |
| xfrm_state_put(x); |
| } |
| |
| static struct xfrm_state *ipcomp6_tunnel_create(struct xfrm_state *x) |
| { |
| struct xfrm_state *t = NULL; |
| |
| t = xfrm_state_alloc(); |
| if (!t) |
| goto out; |
| |
| t->id.proto = IPPROTO_IPV6; |
| t->id.spi = xfrm6_tunnel_alloc_spi((xfrm_address_t *)&x->props.saddr); |
| if (!t->id.spi) |
| goto error; |
| |
| memcpy(t->id.daddr.a6, x->id.daddr.a6, sizeof(struct in6_addr)); |
| memcpy(&t->sel, &x->sel, sizeof(t->sel)); |
| t->props.family = AF_INET6; |
| t->props.mode = x->props.mode; |
| memcpy(t->props.saddr.a6, x->props.saddr.a6, sizeof(struct in6_addr)); |
| |
| if (xfrm_init_state(t)) |
| goto error; |
| |
| atomic_set(&t->tunnel_users, 1); |
| |
| out: |
| return t; |
| |
| error: |
| t->km.state = XFRM_STATE_DEAD; |
| xfrm_state_put(t); |
| t = NULL; |
| goto out; |
| } |
| |
| static int ipcomp6_tunnel_attach(struct xfrm_state *x) |
| { |
| int err = 0; |
| struct xfrm_state *t = NULL; |
| __be32 spi; |
| |
| spi = xfrm6_tunnel_spi_lookup((xfrm_address_t *)&x->props.saddr); |
| if (spi) |
| t = xfrm_state_lookup((xfrm_address_t *)&x->id.daddr, |
| spi, IPPROTO_IPV6, AF_INET6); |
| if (!t) { |
| t = ipcomp6_tunnel_create(x); |
| if (!t) { |
| err = -EINVAL; |
| goto out; |
| } |
| xfrm_state_insert(t); |
| xfrm_state_hold(t); |
| } |
| x->tunnel = t; |
| atomic_inc(&t->tunnel_users); |
| |
| out: |
| return err; |
| } |
| |
| static int ipcomp6_init_state(struct xfrm_state *x) |
| { |
| int err = -EINVAL; |
| |
| x->props.header_len = 0; |
| switch (x->props.mode) { |
| case XFRM_MODE_TRANSPORT: |
| break; |
| case XFRM_MODE_TUNNEL: |
| x->props.header_len += sizeof(struct ipv6hdr); |
| break; |
| default: |
| goto out; |
| } |
| |
| err = ipcomp_init_state(x); |
| if (err) |
| goto out; |
| |
| if (x->props.mode == XFRM_MODE_TUNNEL) { |
| err = ipcomp6_tunnel_attach(x); |
| if (err) |
| goto error_tunnel; |
| } |
| |
| err = 0; |
| out: |
| return err; |
| error_tunnel: |
| ipcomp_destroy(x); |
| |
| goto out; |
| } |
| |
| static const struct xfrm_type ipcomp6_type = |
| { |
| .description = "IPCOMP6", |
| .owner = THIS_MODULE, |
| .proto = IPPROTO_COMP, |
| .init_state = ipcomp6_init_state, |
| .destructor = ipcomp_destroy, |
| .input = ipcomp_input, |
| .output = ipcomp_output, |
| .hdr_offset = xfrm6_find_1stfragopt, |
| }; |
| |
| static struct inet6_protocol ipcomp6_protocol = |
| { |
| .handler = xfrm6_rcv, |
| .err_handler = ipcomp6_err, |
| .flags = INET6_PROTO_NOPOLICY, |
| }; |
| |
| static int __init ipcomp6_init(void) |
| { |
| if (xfrm_register_type(&ipcomp6_type, AF_INET6) < 0) { |
| printk(KERN_INFO "ipcomp6 init: can't add xfrm type\n"); |
| return -EAGAIN; |
| } |
| if (inet6_add_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0) { |
| printk(KERN_INFO "ipcomp6 init: can't add protocol\n"); |
| xfrm_unregister_type(&ipcomp6_type, AF_INET6); |
| return -EAGAIN; |
| } |
| return 0; |
| } |
| |
| static void __exit ipcomp6_fini(void) |
| { |
| if (inet6_del_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0) |
| printk(KERN_INFO "ipv6 ipcomp close: can't remove protocol\n"); |
| if (xfrm_unregister_type(&ipcomp6_type, AF_INET6) < 0) |
| printk(KERN_INFO "ipv6 ipcomp close: can't remove xfrm type\n"); |
| } |
| |
| module_init(ipcomp6_init); |
| module_exit(ipcomp6_fini); |
| MODULE_LICENSE("GPL"); |
| MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173"); |
| MODULE_AUTHOR("Mitsuru KANDA <mk@linux-ipv6.org>"); |
| |
| MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_COMP); |