From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- net/ipv6/ipcomp6.c | 524 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 524 insertions(+) create mode 100644 net/ipv6/ipcomp6.c (limited to 'net/ipv6/ipcomp6.c') diff --git a/net/ipv6/ipcomp6.c b/net/ipv6/ipcomp6.c new file mode 100644 index 00000000000..6cde5310cd7 --- /dev/null +++ b/net/ipv6/ipcomp6.c @@ -0,0 +1,524 @@ +/* + * IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173 + * + * Copyright (C)2003 USAGI/WIDE Project + * + * Author Mitsuru KANDA + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct ipcomp6_tfms { + struct list_head list; + struct crypto_tfm **tfms; + int users; +}; + +static DECLARE_MUTEX(ipcomp6_resource_sem); +static void **ipcomp6_scratches; +static int ipcomp6_scratch_users; +static LIST_HEAD(ipcomp6_tfms_list); + +static int ipcomp6_input(struct xfrm_state *x, struct xfrm_decap_state *decap, struct sk_buff *skb) +{ + int err = 0; + u8 nexthdr = 0; + int hdr_len = skb->h.raw - skb->nh.raw; + unsigned char *tmp_hdr = NULL; + struct ipv6hdr *iph; + int plen, dlen; + struct ipcomp_data *ipcd = x->data; + u8 *start, *scratch; + struct crypto_tfm *tfm; + int cpu; + + if ((skb_is_nonlinear(skb) || skb_cloned(skb)) && + skb_linearize(skb, GFP_ATOMIC) != 0) { + err = -ENOMEM; + goto out; + } + + skb->ip_summed = CHECKSUM_NONE; + + /* Remove ipcomp header and decompress original payload */ + iph = skb->nh.ipv6h; + tmp_hdr = kmalloc(hdr_len, GFP_ATOMIC); + if (!tmp_hdr) + goto out; + memcpy(tmp_hdr, iph, hdr_len); + nexthdr = *(u8 *)skb->data; + skb_pull(skb, sizeof(struct ipv6_comp_hdr)); + skb->nh.raw += sizeof(struct ipv6_comp_hdr); + memcpy(skb->nh.raw, tmp_hdr, hdr_len); + iph = skb->nh.ipv6h; + iph->payload_len = htons(ntohs(iph->payload_len) - sizeof(struct ipv6_comp_hdr)); + skb->h.raw = skb->data; + + /* decompression */ + plen = skb->len; + dlen = IPCOMP_SCRATCH_SIZE; + start = skb->data; + + cpu = get_cpu(); + scratch = *per_cpu_ptr(ipcomp6_scratches, cpu); + tfm = *per_cpu_ptr(ipcd->tfms, cpu); + + err = crypto_comp_decompress(tfm, start, plen, scratch, &dlen); + if (err) { + err = -EINVAL; + goto out_put_cpu; + } + + if (dlen < (plen + sizeof(struct ipv6_comp_hdr))) { + err = -EINVAL; + goto out_put_cpu; + } + + err = pskb_expand_head(skb, 0, dlen - plen, GFP_ATOMIC); + if (err) { + goto out_put_cpu; + } + + skb_put(skb, dlen - plen); + memcpy(skb->data, scratch, dlen); + + iph = skb->nh.ipv6h; + iph->payload_len = htons(skb->len); + +out_put_cpu: + put_cpu(); +out: + if (tmp_hdr) + kfree(tmp_hdr); + if (err) + goto error_out; + return nexthdr; +error_out: + return err; +} + +static int ipcomp6_output(struct xfrm_state *x, struct sk_buff *skb) +{ + int err; + struct ipv6hdr *top_iph; + int hdr_len; + struct ipv6_comp_hdr *ipch; + struct ipcomp_data *ipcd = x->data; + int plen, dlen; + u8 *start, *scratch; + struct crypto_tfm *tfm; + int cpu; + + hdr_len = skb->h.raw - skb->data; + + /* check whether datagram len is larger than threshold */ + if ((skb->len - hdr_len) < ipcd->threshold) { + goto out_ok; + } + + if ((skb_is_nonlinear(skb) || skb_cloned(skb)) && + skb_linearize(skb, GFP_ATOMIC) != 0) { + goto out_ok; + } + + /* compression */ + plen = skb->len - hdr_len; + dlen = IPCOMP_SCRATCH_SIZE; + start = skb->h.raw; + + cpu = get_cpu(); + scratch = *per_cpu_ptr(ipcomp6_scratches, cpu); + tfm = *per_cpu_ptr(ipcd->tfms, cpu); + + err = crypto_comp_compress(tfm, start, plen, scratch, &dlen); + if (err || (dlen + sizeof(struct ipv6_comp_hdr)) >= plen) { + put_cpu(); + goto out_ok; + } + memcpy(start + sizeof(struct ip_comp_hdr), scratch, dlen); + put_cpu(); + pskb_trim(skb, hdr_len + dlen + sizeof(struct ip_comp_hdr)); + + /* insert ipcomp header and replace datagram */ + top_iph = (struct ipv6hdr *)skb->data; + + top_iph->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); + + ipch = (struct ipv6_comp_hdr *)start; + ipch->nexthdr = *skb->nh.raw; + ipch->flags = 0; + ipch->cpi = htons((u16 )ntohl(x->id.spi)); + *skb->nh.raw = IPPROTO_COMP; + +out_ok: + return 0; +} + +static void ipcomp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, + int type, int code, int offset, __u32 info) +{ + u32 spi; + struct ipv6hdr *iph = (struct ipv6hdr*)skb->data; + struct ipv6_comp_hdr *ipcomph = (struct ipv6_comp_hdr*)(skb->data+offset); + struct xfrm_state *x; + + if (type != ICMPV6_DEST_UNREACH && type != ICMPV6_PKT_TOOBIG) + return; + + spi = ntohl(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/" + "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\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); + 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 = 1; + memcpy(t->props.saddr.a6, x->props.saddr.a6, sizeof(struct in6_addr)); + + t->type = xfrm_get_type(IPPROTO_IPV6, t->props.family); + if (t->type == NULL) + goto error; + + if (t->type->init_state(t, NULL)) + goto error; + + t->km.state = XFRM_STATE_VALID; + atomic_set(&t->tunnel_users, 1); + +out: + return t; + +error: + xfrm_state_put(t); + goto out; +} + +static int ipcomp6_tunnel_attach(struct xfrm_state *x) +{ + int err = 0; + struct xfrm_state *t = NULL; + u32 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 void ipcomp6_free_scratches(void) +{ + int i; + void **scratches; + + if (--ipcomp6_scratch_users) + return; + + scratches = ipcomp6_scratches; + if (!scratches) + return; + + for_each_cpu(i) { + void *scratch = *per_cpu_ptr(scratches, i); + if (scratch) + vfree(scratch); + } + + free_percpu(scratches); +} + +static void **ipcomp6_alloc_scratches(void) +{ + int i; + void **scratches; + + if (ipcomp6_scratch_users++) + return ipcomp6_scratches; + + scratches = alloc_percpu(void *); + if (!scratches) + return NULL; + + ipcomp6_scratches = scratches; + + for_each_cpu(i) { + void *scratch = vmalloc(IPCOMP_SCRATCH_SIZE); + if (!scratch) + return NULL; + *per_cpu_ptr(scratches, i) = scratch; + } + + return scratches; +} + +static void ipcomp6_free_tfms(struct crypto_tfm **tfms) +{ + struct ipcomp6_tfms *pos; + int cpu; + + list_for_each_entry(pos, &ipcomp6_tfms_list, list) { + if (pos->tfms == tfms) + break; + } + + BUG_TRAP(pos); + + if (--pos->users) + return; + + list_del(&pos->list); + kfree(pos); + + if (!tfms) + return; + + for_each_cpu(cpu) { + struct crypto_tfm *tfm = *per_cpu_ptr(tfms, cpu); + if (tfm) + crypto_free_tfm(tfm); + } + free_percpu(tfms); +} + +static struct crypto_tfm **ipcomp6_alloc_tfms(const char *alg_name) +{ + struct ipcomp6_tfms *pos; + struct crypto_tfm **tfms; + int cpu; + + /* This can be any valid CPU ID so we don't need locking. */ + cpu = smp_processor_id(); + + list_for_each_entry(pos, &ipcomp6_tfms_list, list) { + struct crypto_tfm *tfm; + + tfms = pos->tfms; + tfm = *per_cpu_ptr(tfms, cpu); + + if (!strcmp(crypto_tfm_alg_name(tfm), alg_name)) { + pos->users++; + return tfms; + } + } + + pos = kmalloc(sizeof(*pos), GFP_KERNEL); + if (!pos) + return NULL; + + pos->users = 1; + INIT_LIST_HEAD(&pos->list); + list_add(&pos->list, &ipcomp6_tfms_list); + + pos->tfms = tfms = alloc_percpu(struct crypto_tfm *); + if (!tfms) + goto error; + + for_each_cpu(cpu) { + struct crypto_tfm *tfm = crypto_alloc_tfm(alg_name, 0); + if (!tfm) + goto error; + *per_cpu_ptr(tfms, cpu) = tfm; + } + + return tfms; + +error: + ipcomp6_free_tfms(tfms); + return NULL; +} + +static void ipcomp6_free_data(struct ipcomp_data *ipcd) +{ + if (ipcd->tfms) + ipcomp6_free_tfms(ipcd->tfms); + ipcomp6_free_scratches(); +} + +static void ipcomp6_destroy(struct xfrm_state *x) +{ + struct ipcomp_data *ipcd = x->data; + if (!ipcd) + return; + xfrm_state_delete_tunnel(x); + down(&ipcomp6_resource_sem); + ipcomp6_free_data(ipcd); + up(&ipcomp6_resource_sem); + kfree(ipcd); + + xfrm6_tunnel_free_spi((xfrm_address_t *)&x->props.saddr); +} + +static int ipcomp6_init_state(struct xfrm_state *x, void *args) +{ + int err; + struct ipcomp_data *ipcd; + struct xfrm_algo_desc *calg_desc; + + err = -EINVAL; + if (!x->calg) + goto out; + + if (x->encap) + goto out; + + err = -ENOMEM; + ipcd = kmalloc(sizeof(*ipcd), GFP_KERNEL); + if (!ipcd) + goto out; + + memset(ipcd, 0, sizeof(*ipcd)); + x->props.header_len = 0; + if (x->props.mode) + x->props.header_len += sizeof(struct ipv6hdr); + + down(&ipcomp6_resource_sem); + if (!ipcomp6_alloc_scratches()) + goto error; + + ipcd->tfms = ipcomp6_alloc_tfms(x->calg->alg_name); + if (!ipcd->tfms) + goto error; + up(&ipcomp6_resource_sem); + + if (x->props.mode) { + err = ipcomp6_tunnel_attach(x); + if (err) + goto error_tunnel; + } + + calg_desc = xfrm_calg_get_byname(x->calg->alg_name, 0); + BUG_ON(!calg_desc); + ipcd->threshold = calg_desc->uinfo.comp.threshold; + x->data = ipcd; + err = 0; +out: + return err; +error_tunnel: + down(&ipcomp6_resource_sem); +error: + ipcomp6_free_data(ipcd); + up(&ipcomp6_resource_sem); + kfree(ipcd); + + goto out; +} + +static struct xfrm_type ipcomp6_type = +{ + .description = "IPCOMP6", + .owner = THIS_MODULE, + .proto = IPPROTO_COMP, + .init_state = ipcomp6_init_state, + .destructor = ipcomp6_destroy, + .input = ipcomp6_input, + .output = ipcomp6_output, +}; + +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 "); + + -- cgit v1.2.3