linux/net/ipv6/ah6.c

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/*
* Copyright (C)2002 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 @USAGI : IPv6 Support
* Kazunori MIYAZAWA @USAGI :
* Kunihiro Ishiguro <kunihiro@ipinfusion.com>
*
* This file is derived from net/ipv4/ah.c.
*/
#include <crypto/hash.h>
#include <linux/module.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <net/ip.h>
#include <net/ah.h>
#include <linux/crypto.h>
#include <linux/pfkeyv2.h>
#include <linux/string.h>
#include <linux/scatterlist.h>
#include <net/icmp.h>
#include <net/ipv6.h>
#include <net/protocol.h>
#include <net/xfrm.h>
#define IPV6HDR_BASELEN 8
struct tmp_ext {
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
struct in6_addr saddr;
#endif
struct in6_addr daddr;
char hdrs[0];
};
struct ah_skb_cb {
struct xfrm_skb_cb xfrm;
void *tmp;
};
#define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0]))
static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags,
unsigned int size)
{
unsigned int len;
len = size + crypto_ahash_digestsize(ahash) +
(crypto_ahash_alignmask(ahash) &
~(crypto_tfm_ctx_alignment() - 1));
len = ALIGN(len, crypto_tfm_ctx_alignment());
len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash);
len = ALIGN(len, __alignof__(struct scatterlist));
len += sizeof(struct scatterlist) * nfrags;
return kmalloc(len, GFP_ATOMIC);
}
static inline struct tmp_ext *ah_tmp_ext(void *base)
{
return base + IPV6HDR_BASELEN;
}
static inline u8 *ah_tmp_auth(u8 *tmp, unsigned int offset)
{
return tmp + offset;
}
static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp,
unsigned int offset)
{
return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1);
}
static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash,
u8 *icv)
{
struct ahash_request *req;
req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash),
crypto_tfm_ctx_alignment());
ahash_request_set_tfm(req, ahash);
return req;
}
static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash,
struct ahash_request *req)
{
return (void *)ALIGN((unsigned long)(req + 1) +
crypto_ahash_reqsize(ahash),
__alignof__(struct scatterlist));
}
static int zero_out_mutable_opts(struct ipv6_opt_hdr *opthdr)
{
u8 *opt = (u8 *)opthdr;
int len = ipv6_optlen(opthdr);
int off = 0;
int optlen = 0;
off += 2;
len -= 2;
while (len > 0) {
switch (opt[off]) {
case IPV6_TLV_PAD0:
optlen = 1;
break;
default:
if (len < 2)
goto bad;
optlen = opt[off+1]+2;
if (len < optlen)
goto bad;
if (opt[off] & 0x20)
memset(&opt[off+2], 0, opt[off+1]);
break;
}
off += optlen;
len -= optlen;
}
if (len == 0)
return 1;
bad:
return 0;
}
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
/**
* ipv6_rearrange_destopt - rearrange IPv6 destination options header
* @iph: IPv6 header
* @destopt: destionation options header
*/
static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt)
{
u8 *opt = (u8 *)destopt;
int len = ipv6_optlen(destopt);
int off = 0;
int optlen = 0;
off += 2;
len -= 2;
while (len > 0) {
switch (opt[off]) {
case IPV6_TLV_PAD0:
optlen = 1;
break;
default:
if (len < 2)
goto bad;
optlen = opt[off+1]+2;
if (len < optlen)
goto bad;
/* Rearrange the source address in @iph and the
* addresses in home address option for final source.
* See 11.3.2 of RFC 3775 for details.
*/
if (opt[off] == IPV6_TLV_HAO) {
struct in6_addr final_addr;
struct ipv6_destopt_hao *hao;
hao = (struct ipv6_destopt_hao *)&opt[off];
if (hao->length != sizeof(hao->addr)) {
if (net_ratelimit())
printk(KERN_WARNING "destopt hao: invalid header length: %u\n", hao->length);
goto bad;
}
ipv6_addr_copy(&final_addr, &hao->addr);
ipv6_addr_copy(&hao->addr, &iph->saddr);
ipv6_addr_copy(&iph->saddr, &final_addr);
}
break;
}
off += optlen;
len -= optlen;
}
/* Note: ok if len == 0 */
bad:
return;
}
#else
static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) {}
#endif
/**
* ipv6_rearrange_rthdr - rearrange IPv6 routing header
* @iph: IPv6 header
* @rthdr: routing header
*
* Rearrange the destination address in @iph and the addresses in @rthdr
* so that they appear in the order they will at the final destination.
* See Appendix A2 of RFC 2402 for details.
*/
static void ipv6_rearrange_rthdr(struct ipv6hdr *iph, struct ipv6_rt_hdr *rthdr)
{
int segments, segments_left;
struct in6_addr *addrs;
struct in6_addr final_addr;
segments_left = rthdr->segments_left;
if (segments_left == 0)
return;
rthdr->segments_left = 0;
/* The value of rthdr->hdrlen has been verified either by the system
* call if it is locally generated, or by ipv6_rthdr_rcv() for incoming
* packets. So we can assume that it is even and that segments is
* greater than or equal to segments_left.
*
* For the same reason we can assume that this option is of type 0.
*/
segments = rthdr->hdrlen >> 1;
addrs = ((struct rt0_hdr *)rthdr)->addr;
ipv6_addr_copy(&final_addr, addrs + segments - 1);
addrs += segments - segments_left;
memmove(addrs + 1, addrs, (segments_left - 1) * sizeof(*addrs));
ipv6_addr_copy(addrs, &iph->daddr);
ipv6_addr_copy(&iph->daddr, &final_addr);
}
static int ipv6_clear_mutable_options(struct ipv6hdr *iph, int len, int dir)
{
union {
struct ipv6hdr *iph;
struct ipv6_opt_hdr *opth;
struct ipv6_rt_hdr *rth;
char *raw;
} exthdr = { .iph = iph };
char *end = exthdr.raw + len;
int nexthdr = iph->nexthdr;
exthdr.iph++;
while (exthdr.raw < end) {
switch (nexthdr) {
case NEXTHDR_DEST:
if (dir == XFRM_POLICY_OUT)
ipv6_rearrange_destopt(iph, exthdr.opth);
case NEXTHDR_HOP:
if (!zero_out_mutable_opts(exthdr.opth)) {
LIMIT_NETDEBUG(
KERN_WARNING "overrun %sopts\n",
nexthdr == NEXTHDR_HOP ?
"hop" : "dest");
return -EINVAL;
}
break;
case NEXTHDR_ROUTING:
ipv6_rearrange_rthdr(iph, exthdr.rth);
break;
default :
return 0;
}
nexthdr = exthdr.opth->nexthdr;
exthdr.raw += ipv6_optlen(exthdr.opth);
}
return 0;
}
static void ah6_output_done(struct crypto_async_request *base, int err)
{
int extlen;
u8 *iph_base;
u8 *icv;
struct sk_buff *skb = base->data;
struct xfrm_state *x = skb_dst(skb)->xfrm;
struct ah_data *ahp = x->data;
struct ipv6hdr *top_iph = ipv6_hdr(skb);
struct ip_auth_hdr *ah = ip_auth_hdr(skb);
struct tmp_ext *iph_ext;
extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr);
if (extlen)
extlen += sizeof(*iph_ext);
iph_base = AH_SKB_CB(skb)->tmp;
iph_ext = ah_tmp_ext(iph_base);
icv = ah_tmp_icv(ahp->ahash, iph_ext, extlen);
memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
memcpy(top_iph, iph_base, IPV6HDR_BASELEN);
if (extlen) {
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
memcpy(&top_iph->saddr, iph_ext, extlen);
#else
memcpy(&top_iph->daddr, iph_ext, extlen);
#endif
}
err = ah->nexthdr;
kfree(AH_SKB_CB(skb)->tmp);
xfrm_output_resume(skb, err);
}
static int ah6_output(struct xfrm_state *x, struct sk_buff *skb)
{
int err;
int nfrags;
int extlen;
u8 *iph_base;
u8 *icv;
u8 nexthdr;
struct sk_buff *trailer;
struct crypto_ahash *ahash;
struct ahash_request *req;
struct scatterlist *sg;
struct ipv6hdr *top_iph;
struct ip_auth_hdr *ah;
struct ah_data *ahp;
struct tmp_ext *iph_ext;
ahp = x->data;
ahash = ahp->ahash;
if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
goto out;
nfrags = err;
skb_push(skb, -skb_network_offset(skb));
extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr);
if (extlen)
extlen += sizeof(*iph_ext);
err = -ENOMEM;
iph_base = ah_alloc_tmp(ahash, nfrags, IPV6HDR_BASELEN + extlen);
if (!iph_base)
goto out;
iph_ext = ah_tmp_ext(iph_base);
icv = ah_tmp_icv(ahash, iph_ext, extlen);
req = ah_tmp_req(ahash, icv);
sg = ah_req_sg(ahash, req);
ah = ip_auth_hdr(skb);
memset(ah->auth_data, 0, ahp->icv_trunc_len);
top_iph = ipv6_hdr(skb);
top_iph->payload_len = htons(skb->len - sizeof(*top_iph));
nexthdr = *skb_mac_header(skb);
*skb_mac_header(skb) = IPPROTO_AH;
/* When there are no extension headers, we only need to save the first
* 8 bytes of the base IP header.
*/
memcpy(iph_base, top_iph, IPV6HDR_BASELEN);
if (extlen) {
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
memcpy(iph_ext, &top_iph->saddr, extlen);
#else
memcpy(iph_ext, &top_iph->daddr, extlen);
#endif
err = ipv6_clear_mutable_options(top_iph,
extlen - sizeof(*iph_ext) +
sizeof(*top_iph),
XFRM_POLICY_OUT);
if (err)
goto out_free;
}
ah->nexthdr = nexthdr;
top_iph->priority = 0;
top_iph->flow_lbl[0] = 0;
top_iph->flow_lbl[1] = 0;
top_iph->flow_lbl[2] = 0;
top_iph->hop_limit = 0;
ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2;
ah->reserved = 0;
ah->spi = x->id.spi;
ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
sg_init_table(sg, nfrags);
skb_to_sgvec(skb, sg, 0, skb->len);
ahash_request_set_crypt(req, sg, icv, skb->len);
ahash_request_set_callback(req, 0, ah6_output_done, skb);
AH_SKB_CB(skb)->tmp = iph_base;
err = crypto_ahash_digest(req);
if (err) {
if (err == -EINPROGRESS)
goto out;
if (err == -EBUSY)
err = NET_XMIT_DROP;
goto out_free;
}
memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
memcpy(top_iph, iph_base, IPV6HDR_BASELEN);
if (extlen) {
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
memcpy(&top_iph->saddr, iph_ext, extlen);
#else
memcpy(&top_iph->daddr, iph_ext, extlen);
#endif
}
out_free:
kfree(iph_base);
out:
return err;
}
static void ah6_input_done(struct crypto_async_request *base, int err)
{
u8 *auth_data;
u8 *icv;
u8 *work_iph;
struct sk_buff *skb = base->data;
struct xfrm_state *x = xfrm_input_state(skb);
struct ah_data *ahp = x->data;
struct ip_auth_hdr *ah = ip_auth_hdr(skb);
int hdr_len = skb_network_header_len(skb);
int ah_hlen = (ah->hdrlen + 2) << 2;
work_iph = AH_SKB_CB(skb)->tmp;
auth_data = ah_tmp_auth(work_iph, hdr_len);
icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len);
err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0;
if (err)
goto out;
skb->network_header += ah_hlen;
memcpy(skb_network_header(skb), work_iph, hdr_len);
__skb_pull(skb, ah_hlen + hdr_len);
skb_set_transport_header(skb, -hdr_len);
err = ah->nexthdr;
out:
kfree(AH_SKB_CB(skb)->tmp);
xfrm_input_resume(skb, err);
}
static int ah6_input(struct xfrm_state *x, struct sk_buff *skb)
{
/*
* Before process AH
* [IPv6][Ext1][Ext2][AH][Dest][Payload]
* |<-------------->| hdr_len
*
* To erase AH:
* Keeping copy of cleared headers. After AH processing,
* Moving the pointer of skb->network_header by using skb_pull as long
* as AH header length. Then copy back the copy as long as hdr_len
* If destination header following AH exists, copy it into after [Ext2].
*
* |<>|[IPv6][Ext1][Ext2][Dest][Payload]
* There is offset of AH before IPv6 header after the process.
*/
u8 *auth_data;
u8 *icv;
u8 *work_iph;
struct sk_buff *trailer;
struct crypto_ahash *ahash;
struct ahash_request *req;
struct scatterlist *sg;
struct ip_auth_hdr *ah;
struct ipv6hdr *ip6h;
struct ah_data *ahp;
u16 hdr_len;
u16 ah_hlen;
int nexthdr;
int nfrags;
int err = -ENOMEM;
if (!pskb_may_pull(skb, sizeof(struct ip_auth_hdr)))
goto out;
/* We are going to _remove_ AH header to keep sockets happy,
* so... Later this can change. */
if (skb_cloned(skb) &&
pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
goto out;
skb->ip_summed = CHECKSUM_NONE;
hdr_len = skb_network_header_len(skb);
ah = (struct ip_auth_hdr *)skb->data;
ahp = x->data;
ahash = ahp->ahash;
nexthdr = ah->nexthdr;
ah_hlen = (ah->hdrlen + 2) << 2;
if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) &&
ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len))
goto out;
if (!pskb_may_pull(skb, ah_hlen))
goto out;
if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
goto out;
nfrags = err;
ah = (struct ip_auth_hdr *)skb->data;
ip6h = ipv6_hdr(skb);
skb_push(skb, hdr_len);
work_iph = ah_alloc_tmp(ahash, nfrags, hdr_len + ahp->icv_trunc_len);
if (!work_iph)
goto out;
auth_data = ah_tmp_auth(work_iph, hdr_len);
icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len);
req = ah_tmp_req(ahash, icv);
sg = ah_req_sg(ahash, req);
memcpy(work_iph, ip6h, hdr_len);
memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len);
memset(ah->auth_data, 0, ahp->icv_trunc_len);
if (ipv6_clear_mutable_options(ip6h, hdr_len, XFRM_POLICY_IN))
goto out_free;
ip6h->priority = 0;
ip6h->flow_lbl[0] = 0;
ip6h->flow_lbl[1] = 0;
ip6h->flow_lbl[2] = 0;
ip6h->hop_limit = 0;
sg_init_table(sg, nfrags);
skb_to_sgvec(skb, sg, 0, skb->len);
ahash_request_set_crypt(req, sg, icv, skb->len);
ahash_request_set_callback(req, 0, ah6_input_done, skb);
AH_SKB_CB(skb)->tmp = work_iph;
err = crypto_ahash_digest(req);
if (err) {
if (err == -EINPROGRESS)
goto out;
if (err == -EBUSY)
err = NET_XMIT_DROP;
goto out_free;
}
err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0;
if (err)
goto out_free;
skb->network_header += ah_hlen;
memcpy(skb_network_header(skb), work_iph, hdr_len);
skb->transport_header = skb->network_header;
__skb_pull(skb, ah_hlen + hdr_len);
err = nexthdr;
out_free:
kfree(work_iph);
out:
return err;
}
static void ah6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
u8 type, u8 code, int offset, __be32 info)
{
struct net *net = dev_net(skb->dev);
struct ipv6hdr *iph = (struct ipv6hdr*)skb->data;
struct ip_auth_hdr *ah = (struct ip_auth_hdr*)(skb->data+offset);
struct xfrm_state *x;
if (type != ICMPV6_DEST_UNREACH &&
type != ICMPV6_PKT_TOOBIG)
return;
x = xfrm_state_lookup(net, skb->mark, (xfrm_address_t *)&iph->daddr, ah->spi, IPPROTO_AH, AF_INET6);
if (!x)
return;
NETDEBUG(KERN_DEBUG "pmtu discovery on SA AH/%08x/%pI6\n",
ntohl(ah->spi), &iph->daddr);
xfrm_state_put(x);
}
static int ah6_init_state(struct xfrm_state *x)
{
struct ah_data *ahp = NULL;
struct xfrm_algo_desc *aalg_desc;
struct crypto_ahash *ahash;
if (!x->aalg)
goto error;
if (x->encap)
goto error;
ahp = kzalloc(sizeof(*ahp), GFP_KERNEL);
if (ahp == NULL)
return -ENOMEM;
ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0);
if (IS_ERR(ahash))
goto error;
ahp->ahash = ahash;
if (crypto_ahash_setkey(ahash, x->aalg->alg_key,
(x->aalg->alg_key_len + 7) / 8))
goto error;
/*
* Lookup the algorithm description maintained by xfrm_algo,
* verify crypto transform properties, and store information
* we need for AH processing. This lookup cannot fail here
* after a successful crypto_alloc_hash().
*/
aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
BUG_ON(!aalg_desc);
if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
crypto_ahash_digestsize(ahash)) {
printk(KERN_INFO "AH: %s digestsize %u != %hu\n",
x->aalg->alg_name, crypto_ahash_digestsize(ahash),
aalg_desc->uinfo.auth.icv_fullbits/8);
goto error;
}
ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8;
ahp->icv_trunc_len = x->aalg->alg_trunc_len/8;
BUG_ON(ahp->icv_trunc_len > MAX_AH_AUTH_LEN);
x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) +
ahp->icv_trunc_len);
switch (x->props.mode) {
case XFRM_MODE_BEET:
case XFRM_MODE_TRANSPORT:
break;
case XFRM_MODE_TUNNEL:
x->props.header_len += sizeof(struct ipv6hdr);
break;
default:
goto error;
}
x->data = ahp;
return 0;
error:
if (ahp) {
crypto_free_ahash(ahp->ahash);
kfree(ahp);
}
return -EINVAL;
}
static void ah6_destroy(struct xfrm_state *x)
{
struct ah_data *ahp = x->data;
if (!ahp)
return;
crypto_free_ahash(ahp->ahash);
kfree(ahp);
}
static const struct xfrm_type ah6_type =
{
.description = "AH6",
.owner = THIS_MODULE,
.proto = IPPROTO_AH,
.flags = XFRM_TYPE_REPLAY_PROT,
.init_state = ah6_init_state,
.destructor = ah6_destroy,
.input = ah6_input,
.output = ah6_output,
.hdr_offset = xfrm6_find_1stfragopt,
};
static const struct inet6_protocol ah6_protocol = {
.handler = xfrm6_rcv,
.err_handler = ah6_err,
.flags = INET6_PROTO_NOPOLICY,
};
static int __init ah6_init(void)
{
if (xfrm_register_type(&ah6_type, AF_INET6) < 0) {
printk(KERN_INFO "ipv6 ah init: can't add xfrm type\n");
return -EAGAIN;
}
if (inet6_add_protocol(&ah6_protocol, IPPROTO_AH) < 0) {
printk(KERN_INFO "ipv6 ah init: can't add protocol\n");
xfrm_unregister_type(&ah6_type, AF_INET6);
return -EAGAIN;
}
return 0;
}
static void __exit ah6_fini(void)
{
if (inet6_del_protocol(&ah6_protocol, IPPROTO_AH) < 0)
printk(KERN_INFO "ipv6 ah close: can't remove protocol\n");
if (xfrm_unregister_type(&ah6_type, AF_INET6) < 0)
printk(KERN_INFO "ipv6 ah close: can't remove xfrm type\n");
}
module_init(ah6_init);
module_exit(ah6_fini);
MODULE_LICENSE("GPL");
MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_AH);