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freebsd/sys/netinet6/ah_core.c
Yoshinobu Inoue f7d7fca7fd Prototype fix for IPsec authentication related functions 
Some of IPsec authentication related functions should have
  'const' for its 2nd argument, but not now.
  But if someone try to use them, and passed const data for
  those functions, then much bogus compile warnings will be
  generated.
  So those funcs prototype should be modified.

Requested by: archie
Approved by: jkh
2000-02-10 19:35:53 +00:00

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/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/*
* RFC1826/2402 authentication header.
*/
#include "opt_inet6.h"
#include "opt_ipsec.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/in_var.h>
#include <netinet/in_pcb.h>
#ifdef INET6
#include <netinet6/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/icmp6.h>
#endif
#include <netinet6/ipsec.h>
#include <netinet6/ah.h>
#ifdef INET6
#include <netinet6/ipsec6.h>
#include <netinet6/ah6.h>
#endif
#ifdef IPSEC_ESP
#include <netinet6/esp.h>
#ifdef INET6
#include <netinet6/esp6.h>
#endif
#endif
#include <net/pfkeyv2.h>
#include <netkey/key_var.h>
#include <netkey/keydb.h>
#include <sys/md5.h>
#include <crypto/sha1.h>
#include <net/net_osdep.h>
#define HMACSIZE 16
#ifdef INET6
#define ZEROBUFLEN 256
static char zerobuf[ZEROBUFLEN];
#endif
static int ah_sumsiz_1216 __P((struct secasvar *));
static int ah_sumsiz_zero __P((struct secasvar *));
static int ah_none_mature __P((struct secasvar *));
static void ah_none_init __P((struct ah_algorithm_state *,
struct secasvar *));
static void ah_none_loop __P((struct ah_algorithm_state *, const caddr_t,
size_t));
static void ah_none_result __P((struct ah_algorithm_state *, caddr_t));
static int ah_keyed_md5_mature __P((struct secasvar *));
static void ah_keyed_md5_init __P((struct ah_algorithm_state *,
struct secasvar *));
static void ah_keyed_md5_loop __P((struct ah_algorithm_state *, const caddr_t,
size_t));
static void ah_keyed_md5_result __P((struct ah_algorithm_state *, caddr_t));
static int ah_keyed_sha1_mature __P((struct secasvar *));
static void ah_keyed_sha1_init __P((struct ah_algorithm_state *,
struct secasvar *));
static void ah_keyed_sha1_loop __P((struct ah_algorithm_state *, const caddr_t,
size_t));
static void ah_keyed_sha1_result __P((struct ah_algorithm_state *, caddr_t));
static int ah_hmac_md5_mature __P((struct secasvar *));
static void ah_hmac_md5_init __P((struct ah_algorithm_state *,
struct secasvar *));
static void ah_hmac_md5_loop __P((struct ah_algorithm_state *, const caddr_t,
size_t));
static void ah_hmac_md5_result __P((struct ah_algorithm_state *, caddr_t));
static int ah_hmac_sha1_mature __P((struct secasvar *));
static void ah_hmac_sha1_init __P((struct ah_algorithm_state *,
struct secasvar *));
static void ah_hmac_sha1_loop __P((struct ah_algorithm_state *, const caddr_t,
size_t));
static void ah_hmac_sha1_result __P((struct ah_algorithm_state *, caddr_t));
/* checksum algorithms */
/* NOTE: The order depends on SADB_AALG_x in netkey/keyv2.h */
struct ah_algorithm ah_algorithms[] = {
{ 0, 0, 0, 0, 0, 0, },
{ ah_sumsiz_1216, ah_hmac_md5_mature, 128, 128,
ah_hmac_md5_init, ah_hmac_md5_loop, ah_hmac_md5_result, },
{ ah_sumsiz_1216, ah_hmac_sha1_mature, 160, 160,
ah_hmac_sha1_init, ah_hmac_sha1_loop, ah_hmac_sha1_result, },
{ ah_sumsiz_1216, ah_keyed_md5_mature, 128, 128,
ah_keyed_md5_init, ah_keyed_md5_loop, ah_keyed_md5_result, },
{ ah_sumsiz_1216, ah_keyed_sha1_mature, 160, 160,
ah_keyed_sha1_init, ah_keyed_sha1_loop, ah_keyed_sha1_result, },
{ ah_sumsiz_zero, ah_none_mature, 0, 2048,
ah_none_init, ah_none_loop, ah_none_result, },
};
static int
ah_sumsiz_1216(sav)
struct secasvar *sav;
{
if (!sav)
return -1;
if (sav->flags & SADB_X_EXT_OLD)
return 16;
else
return 12;
}
static int
ah_sumsiz_zero(sav)
struct secasvar *sav;
{
if (!sav)
return -1;
return 0;
}
static int
ah_none_mature(sav)
struct secasvar *sav;
{
if (sav->sah->saidx.proto == IPPROTO_AH) {
printf("ah_none_mature: protocol and algorithm mismatch.\n");
return 1;
}
return 0;
}
static void
ah_none_init(state, sav)
struct ah_algorithm_state *state;
struct secasvar *sav;
{
state->foo = NULL;
}
static void
ah_none_loop(state, addr, len)
struct ah_algorithm_state *state;
const caddr_t addr;
size_t len;
{
}
static void
ah_none_result(state, addr)
struct ah_algorithm_state *state;
caddr_t addr;
{
}
static int
ah_keyed_md5_mature(sav)
struct secasvar *sav;
{
/* anything is okay */
return 0;
}
static void
ah_keyed_md5_init(state, sav)
struct ah_algorithm_state *state;
struct secasvar *sav;
{
if (!state)
panic("ah_keyed_md5_init: what?");
state->sav = sav;
state->foo = (void *)malloc(sizeof(MD5_CTX), M_TEMP, M_NOWAIT);
if (state->foo == NULL)
panic("ah_keyed_md5_init: what?");
MD5Init((MD5_CTX *)state->foo);
if (state->sav) {
MD5Update((MD5_CTX *)state->foo,
(u_int8_t *)_KEYBUF(state->sav->key_auth),
(u_int)_KEYLEN(state->sav->key_auth));
{
/*
* Pad after the key.
* We cannot simply use md5_pad() since the function
* won't update the total length.
*/
size_t padlen;
size_t keybitlen;
u_int8_t buf[32];
if (_KEYLEN(state->sav->key_auth) < 56)
padlen = 64 - 8 - _KEYLEN(state->sav->key_auth);
else
padlen = 64 + 64 - 8 - _KEYLEN(state->sav->key_auth);
keybitlen = _KEYLEN(state->sav->key_auth);
keybitlen *= 8;
buf[0] = 0x80;
MD5Update((MD5_CTX *)state->foo, &buf[0], 1);
padlen--;
bzero(buf, sizeof(buf));
while (sizeof(buf) < padlen) {
MD5Update((MD5_CTX *)state->foo, &buf[0], sizeof(buf));
padlen -= sizeof(buf);
}
if (padlen) {
MD5Update((MD5_CTX *)state->foo, &buf[0], padlen);
}
buf[0] = (keybitlen >> 0) & 0xff;
buf[1] = (keybitlen >> 8) & 0xff;
buf[2] = (keybitlen >> 16) & 0xff;
buf[3] = (keybitlen >> 24) & 0xff;
MD5Update((MD5_CTX *)state->foo, buf, 8);
}
}
}
static void
ah_keyed_md5_loop(state, addr, len)
struct ah_algorithm_state *state;
const caddr_t addr;
size_t len;
{
if (!state)
panic("ah_keyed_md5_loop: what?");
MD5Update((MD5_CTX *)state->foo, addr, len);
}
static void
ah_keyed_md5_result(state, addr)
struct ah_algorithm_state *state;
caddr_t addr;
{
u_char digest[16];
if (!state)
panic("ah_keyed_md5_result: what?");
if (state->sav) {
MD5Update((MD5_CTX *)state->foo,
(u_int8_t *)_KEYBUF(state->sav->key_auth),
(u_int)_KEYLEN(state->sav->key_auth));
}
MD5Final(&digest[0], (MD5_CTX *)state->foo);
free(state->foo, M_TEMP);
bcopy(&digest[0], (void *)addr, sizeof(digest));
}
static int
ah_keyed_sha1_mature(sav)
struct secasvar *sav;
{
struct ah_algorithm *algo;
if (!sav->key_auth) {
printf("esp_keyed_sha1_mature: no key is given.\n");
return 1;
}
algo = &ah_algorithms[sav->alg_auth];
if (sav->key_auth->sadb_key_bits < algo->keymin
|| algo->keymax < sav->key_auth->sadb_key_bits) {
printf("ah_keyed_sha1_mature: invalid key length %d.\n",
sav->key_auth->sadb_key_bits);
return 1;
}
return 0;
}
static void
ah_keyed_sha1_init(state, sav)
struct ah_algorithm_state *state;
struct secasvar *sav;
{
SHA1_CTX *ctxt;
if (!state)
panic("ah_keyed_sha1_init: what?");
state->sav = sav;
state->foo = (void *)malloc(sizeof(SHA1_CTX), M_TEMP, M_NOWAIT);
if (!state->foo)
panic("ah_keyed_sha1_init: what?");
ctxt = (SHA1_CTX *)state->foo;
SHA1Init(ctxt);
if (state->sav) {
SHA1Update(ctxt, (u_int8_t *)_KEYBUF(state->sav->key_auth),
(u_int)_KEYLEN(state->sav->key_auth));
{
/*
* Pad after the key.
*/
size_t padlen;
size_t keybitlen;
u_int8_t buf[32];
if (_KEYLEN(state->sav->key_auth) < 56)
padlen = 64 - 8 - _KEYLEN(state->sav->key_auth);
else
padlen = 64 + 64 - 8 - _KEYLEN(state->sav->key_auth);
keybitlen = _KEYLEN(state->sav->key_auth);
keybitlen *= 8;
buf[0] = 0x80;
SHA1Update(ctxt, &buf[0], 1);
padlen--;
bzero(buf, sizeof(buf));
while (sizeof(buf) < padlen) {
SHA1Update(ctxt, &buf[0], sizeof(buf));
padlen -= sizeof(buf);
}
if (padlen) {
SHA1Update(ctxt, &buf[0], padlen);
}
buf[0] = (keybitlen >> 0) & 0xff;
buf[1] = (keybitlen >> 8) & 0xff;
buf[2] = (keybitlen >> 16) & 0xff;
buf[3] = (keybitlen >> 24) & 0xff;
SHA1Update(ctxt, buf, 8);
}
}
}
static void
ah_keyed_sha1_loop(state, addr, len)
struct ah_algorithm_state *state;
const caddr_t addr;
size_t len;
{
SHA1_CTX *ctxt;
if (!state || !state->foo)
panic("ah_keyed_sha1_loop: what?");
ctxt = (SHA1_CTX *)state->foo;
sha1_loop(ctxt, (caddr_t)addr, (size_t)len);
}
static void
ah_keyed_sha1_result(state, addr)
struct ah_algorithm_state *state;
caddr_t addr;
{
u_char digest[SHA1_RESULTLEN]; /* SHA-1 generates 160 bits */
SHA1_CTX *ctxt;
if (!state || !state->foo)
panic("ah_keyed_sha1_result: what?");
ctxt = (SHA1_CTX *)state->foo;
if (state->sav) {
SHA1Update(ctxt, (u_int8_t *)_KEYBUF(state->sav->key_auth),
(u_int)_KEYLEN(state->sav->key_auth));
}
SHA1Final((caddr_t)&digest[0], ctxt);
bcopy(&digest[0], (void *)addr, HMACSIZE);
free(state->foo, M_TEMP);
}
static int
ah_hmac_md5_mature(sav)
struct secasvar *sav;
{
struct ah_algorithm *algo;
if (!sav->key_auth) {
printf("esp_hmac_md5_mature: no key is given.\n");
return 1;
}
algo = &ah_algorithms[sav->alg_auth];
if (sav->key_auth->sadb_key_bits < algo->keymin
|| algo->keymax < sav->key_auth->sadb_key_bits) {
printf("ah_hmac_md5_mature: invalid key length %d.\n",
sav->key_auth->sadb_key_bits);
return 1;
}
return 0;
}
static void
ah_hmac_md5_init(state, sav)
struct ah_algorithm_state *state;
struct secasvar *sav;
{
u_char *ipad;
u_char *opad;
u_char tk[16];
u_char *key;
size_t keylen;
size_t i;
MD5_CTX *ctxt;
if (!state)
panic("ah_hmac_md5_init: what?");
state->sav = sav;
state->foo = (void *)malloc(64 + 64 + sizeof(MD5_CTX), M_TEMP, M_NOWAIT);
if (!state->foo)
panic("ah_hmac_md5_init: what?");
ipad = (u_char *)state->foo;
opad = (u_char *)(ipad + 64);
ctxt = (MD5_CTX *)(opad + 64);
/* compress the key if necessery */
if (64 < _KEYLEN(state->sav->key_auth)) {
MD5Init(ctxt);
MD5Update(ctxt, _KEYBUF(state->sav->key_auth),
_KEYLEN(state->sav->key_auth));
MD5Final(&tk[0], ctxt);
key = &tk[0];
keylen = 16;
} else {
key = _KEYBUF(state->sav->key_auth);
keylen = _KEYLEN(state->sav->key_auth);
}
bzero(ipad, 64);
bzero(opad, 64);
bcopy(key, ipad, keylen);
bcopy(key, opad, keylen);
for (i = 0; i < 64; i++) {
ipad[i] ^= 0x36;
opad[i] ^= 0x5c;
}
MD5Init(ctxt);
MD5Update(ctxt, ipad, 64);
}
static void
ah_hmac_md5_loop(state, addr, len)
struct ah_algorithm_state *state;
const caddr_t addr;
size_t len;
{
MD5_CTX *ctxt;
if (!state || !state->foo)
panic("ah_hmac_md5_loop: what?");
ctxt = (MD5_CTX *)(((caddr_t)state->foo) + 128);
MD5Update(ctxt, addr, len);
}
static void
ah_hmac_md5_result(state, addr)
struct ah_algorithm_state *state;
caddr_t addr;
{
u_char digest[16];
u_char *ipad;
u_char *opad;
MD5_CTX *ctxt;
if (!state || !state->foo)
panic("ah_hmac_md5_result: what?");
ipad = (u_char *)state->foo;
opad = (u_char *)(ipad + 64);
ctxt = (MD5_CTX *)(opad + 64);
MD5Final(&digest[0], ctxt);
MD5Init(ctxt);
MD5Update(ctxt, opad, 64);
MD5Update(ctxt, &digest[0], sizeof(digest));
MD5Final(&digest[0], ctxt);
bcopy(&digest[0], (void *)addr, HMACSIZE);
free(state->foo, M_TEMP);
}
static int
ah_hmac_sha1_mature(sav)
struct secasvar *sav;
{
struct ah_algorithm *algo;
if (!sav->key_auth) {
printf("esp_hmac_sha1_mature: no key is given.\n");
return 1;
}
algo = &ah_algorithms[sav->alg_auth];
if (sav->key_auth->sadb_key_bits < algo->keymin
|| algo->keymax < sav->key_auth->sadb_key_bits) {
printf("ah_hmac_sha1_mature: invalid key length %d.\n",
sav->key_auth->sadb_key_bits);
return 1;
}
return 0;
}
static void
ah_hmac_sha1_init(state, sav)
struct ah_algorithm_state *state;
struct secasvar *sav;
{
u_char *ipad;
u_char *opad;
SHA1_CTX *ctxt;
u_char tk[SHA1_RESULTLEN]; /* SHA-1 generates 160 bits */
u_char *key;
size_t keylen;
size_t i;
if (!state)
panic("ah_hmac_sha1_init: what?");
state->sav = sav;
state->foo = (void *)malloc(64 + 64 + sizeof(SHA1_CTX),
M_TEMP, M_NOWAIT);
if (!state->foo)
panic("ah_hmac_sha1_init: what?");
ipad = (u_char *)state->foo;
opad = (u_char *)(ipad + 64);
ctxt = (SHA1_CTX *)(opad + 64);
/* compress the key if necessery */
if (64 < _KEYLEN(state->sav->key_auth)) {
SHA1Init(ctxt);
SHA1Update(ctxt, _KEYBUF(state->sav->key_auth),
_KEYLEN(state->sav->key_auth));
SHA1Final(&tk[0], ctxt);
key = &tk[0];
keylen = SHA1_RESULTLEN;
} else {
key = _KEYBUF(state->sav->key_auth);
keylen = _KEYLEN(state->sav->key_auth);
}
bzero(ipad, 64);
bzero(opad, 64);
bcopy(key, ipad, keylen);
bcopy(key, opad, keylen);
for (i = 0; i < 64; i++) {
ipad[i] ^= 0x36;
opad[i] ^= 0x5c;
}
SHA1Init(ctxt);
SHA1Update(ctxt, ipad, 64);
}
static void
ah_hmac_sha1_loop(state, addr, len)
struct ah_algorithm_state *state;
const caddr_t addr;
size_t len;
{
SHA1_CTX *ctxt;
if (!state || !state->foo)
panic("ah_hmac_sha1_loop: what?");
ctxt = (SHA1_CTX *)(((u_char *)state->foo) + 128);
SHA1Update(ctxt, (caddr_t)addr, (size_t)len);
}
static void
ah_hmac_sha1_result(state, addr)
struct ah_algorithm_state *state;
caddr_t addr;
{
u_char digest[SHA1_RESULTLEN]; /* SHA-1 generates 160 bits */
u_char *ipad;
u_char *opad;
SHA1_CTX *ctxt;
if (!state || !state->foo)
panic("ah_hmac_sha1_result: what?");
ipad = (u_char *)state->foo;
opad = (u_char *)(ipad + 64);
ctxt = (SHA1_CTX *)(opad + 64);
SHA1Final((caddr_t)&digest[0], ctxt);
SHA1Init(ctxt);
SHA1Update(ctxt, opad, 64);
SHA1Update(ctxt, (caddr_t)&digest[0], sizeof(digest));
SHA1Final((caddr_t)&digest[0], ctxt);
bcopy(&digest[0], (void *)addr, HMACSIZE);
free(state->foo, M_TEMP);
}
/*------------------------------------------------------------*/
/*
* go generate the checksum.
*/
int
ah4_calccksum(m0, ahdat, algo, sav)
struct mbuf *m0;
caddr_t ahdat;
struct ah_algorithm *algo;
struct secasvar *sav;
{
struct mbuf *m;
int hdrtype;
u_char *p;
size_t advancewidth;
struct ah_algorithm_state algos;
int tlen;
u_char sumbuf[AH_MAXSUMSIZE];
int error = 0;
hdrtype = -1; /*dummy, it is called IPPROTO_IP*/
m = m0;
p = mtod(m, u_char *);
(algo->init)(&algos, sav);
advancewidth = 0; /*safety*/
again:
/* gory. */
switch (hdrtype) {
case -1: /*first one*/
{
/*
* copy ip hdr, modify to fit the AH checksum rule,
* then take a checksum.
* XXX need to care about source routing... jesus.
*/
struct ip iphdr;
size_t hlen;
bcopy((caddr_t)p, (caddr_t)&iphdr, sizeof(struct ip));
#ifdef _IP_VHL
hlen = IP_VHL_HL(iphdr.ip_vhl) << 2;
#else
hlen = iphdr.ip_hl << 2;
#endif
iphdr.ip_ttl = 0;
iphdr.ip_sum = htons(0);
if (ip4_ah_cleartos) iphdr.ip_tos = 0;
iphdr.ip_off = htons(ntohs(iphdr.ip_off) & ip4_ah_offsetmask);
(algo->update)(&algos, (caddr_t)&iphdr, sizeof(struct ip));
if (hlen != sizeof(struct ip)) {
u_char *p;
int i, j;
int l, skip;
u_char dummy[4];
/*
* IP options processing.
* See RFC2402 appendix A.
*/
bzero(dummy, sizeof(dummy));
p = mtod(m, u_char *);
i = sizeof(struct ip);
while (i < hlen) {
skip = 1;
switch (p[i + IPOPT_OPTVAL]) {
case IPOPT_EOL:
case IPOPT_NOP:
l = 1;
skip = 0;
break;
case IPOPT_SECURITY: /* 0x82 */
case 0x85: /* Extended security */
case 0x86: /* Commercial security */
case 0x94: /* Router alert */
case 0x95: /* RFC1770 */
l = p[i + IPOPT_OLEN];
skip = 0;
break;
default:
l = p[i + IPOPT_OLEN];
skip = 1;
break;
}
if (l <= 0 || hlen - i < l) {
printf("ah4_input: invalid IP option "
"(type=%02x len=%02x)\n",
p[i + IPOPT_OPTVAL],
p[i + IPOPT_OLEN]);
break;
}
if (skip) {
for (j = 0; j < l / sizeof(dummy); j++)
(algo->update)(&algos, dummy, sizeof(dummy));
(algo->update)(&algos, dummy, l % sizeof(dummy));
} else
(algo->update)(&algos, p + i, l);
if (p[i + IPOPT_OPTVAL] == IPOPT_EOL)
break;
i += l;
}
}
hdrtype = (iphdr.ip_p) & 0xff;
advancewidth = hlen;
break;
}
case IPPROTO_AH:
{
u_char dummy[4];
int siz;
int hdrsiz;
hdrsiz = (sav->flags & SADB_X_EXT_OLD) ?
sizeof(struct ah) : sizeof(struct newah);
(algo->update)(&algos, p, hdrsiz);
/* key data region. */
siz = (*algo->sumsiz)(sav);
bzero(&dummy[0], sizeof(dummy));
while (sizeof(dummy) <= siz) {
(algo->update)(&algos, dummy, sizeof(dummy));
siz -= sizeof(dummy);
}
/* can't happen, but just in case */
if (siz)
(algo->update)(&algos, dummy, siz);
/* padding region, just in case */
siz = (((struct ah *)p)->ah_len << 2) - (*algo->sumsiz)(sav);
if ((sav->flags & SADB_X_EXT_OLD) == 0)
siz -= 4; /* sequence number field */
if (0 < siz) {
/* RFC 1826 */
(algo->update)(&algos, p + hdrsiz + (*algo->sumsiz)(sav),
siz);
}
hdrtype = ((struct ah *)p)->ah_nxt;
advancewidth = hdrsiz;
advancewidth += ((struct ah *)p)->ah_len << 2;
if ((sav->flags & SADB_X_EXT_OLD) == 0)
advancewidth -= 4; /* sequence number field */
break;
}
default:
printf("ah4_calccksum: unexpected hdrtype=%x; "
"treating rest as payload\n", hdrtype);
/*fall through*/
case IPPROTO_ICMP:
case IPPROTO_IGMP:
case IPPROTO_IPIP:
#ifdef INET6
case IPPROTO_IPV6:
case IPPROTO_ICMPV6:
#endif
case IPPROTO_UDP:
case IPPROTO_TCP:
case IPPROTO_ESP:
while (m) {
tlen = m->m_len - (p - mtod(m, u_char *));
(algo->update)(&algos, p, tlen);
m = m->m_next;
p = m ? mtod(m, u_char *) : NULL;
}
advancewidth = 0; /*loop finished*/
break;
}
if (advancewidth) {
/* is it safe? */
while (m && advancewidth) {
tlen = m->m_len - (p - mtod(m, u_char *));
if (advancewidth < tlen) {
p += advancewidth;
advancewidth = 0;
} else {
advancewidth -= tlen;
m = m->m_next;
if (m)
p = mtod(m, u_char *);
else {
printf("ERR: hit the end-of-mbuf...\n");
p = NULL;
}
}
}
if (m)
goto again;
}
/* for HMAC algorithms... */
(algo->result)(&algos, &sumbuf[0]);
bcopy(&sumbuf[0], ahdat, (*algo->sumsiz)(sav));
return error;
}
#ifdef INET6
/*
* go generate the checksum. This function won't modify the mbuf chain
* except AH itself.
*/
int
ah6_calccksum(m0, ahdat, algo, sav)
struct mbuf *m0;
caddr_t ahdat;
struct ah_algorithm *algo;
struct secasvar *sav;
{
struct mbuf *m;
int hdrtype;
u_char *p;
size_t advancewidth;
struct ah_algorithm_state algos;
int tlen;
int error = 0;
u_char sumbuf[AH_MAXSUMSIZE];
int nest;
hdrtype = -1; /*dummy, it is called IPPROTO_IPV6 */
m = m0;
p = mtod(m, u_char *);
(algo->init)(&algos, sav);
advancewidth = 0; /*safety*/
nest = 0;
again:
if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) {
ip6stat.ip6s_toomanyhdr++;
error = EINVAL; /*XXX*/
goto bad;
}
/* gory. */
switch (hdrtype) {
case -1: /*first one*/
{
struct ip6_hdr ip6copy;
bcopy(p, &ip6copy, sizeof(struct ip6_hdr));
/* RFC2402 */
ip6copy.ip6_flow = 0;
ip6copy.ip6_vfc = IPV6_VERSION;
ip6copy.ip6_hlim = 0;
if (IN6_IS_ADDR_LINKLOCAL(&ip6copy.ip6_src))
ip6copy.ip6_src.s6_addr16[1] = 0x0000;
if (IN6_IS_ADDR_LINKLOCAL(&ip6copy.ip6_dst))
ip6copy.ip6_dst.s6_addr16[1] = 0x0000;
(algo->update)(&algos, (caddr_t)&ip6copy,
sizeof(struct ip6_hdr));
hdrtype = (((struct ip6_hdr *)p)->ip6_nxt) & 0xff;
advancewidth = sizeof(struct ip6_hdr);
break;
}
case IPPROTO_AH:
{
u_char dummy[4];
int siz;
int hdrsiz;
hdrsiz = (sav->flags & SADB_X_EXT_OLD) ?
sizeof(struct ah) : sizeof(struct newah);
(algo->update)(&algos, p, hdrsiz);
/* key data region. */
siz = (*algo->sumsiz)(sav);
bzero(&dummy[0], 4);
while (4 <= siz) {
(algo->update)(&algos, dummy, 4);
siz -= 4;
}
/* can't happen, but just in case */
if (siz)
(algo->update)(&algos, dummy, siz);
/* padding region, just in case */
siz = (((struct ah *)p)->ah_len << 2) - (*algo->sumsiz)(sav);
if ((sav->flags & SADB_X_EXT_OLD) == 0)
siz -= 4; /* sequence number field */
if (0 < siz) {
(algo->update)(&algos, p + hdrsiz + (*algo->sumsiz)(sav),
siz);
}
hdrtype = ((struct ah *)p)->ah_nxt;
advancewidth = hdrsiz;
advancewidth += ((struct ah *)p)->ah_len << 2;
if ((sav->flags & SADB_X_EXT_OLD) == 0)
advancewidth -= 4; /* sequence number field */
break;
}
case IPPROTO_HOPOPTS:
case IPPROTO_DSTOPTS:
{
int hdrlen, optlen;
u_int8_t *optp, *lastp = p, *optend, opt;
tlen = m->m_len - (p - mtod(m, u_char *));
/* We assume all the options is contained in a single mbuf */
if (tlen < sizeof(struct ip6_ext)) {
error = EINVAL;
goto bad;
}
hdrlen = (((struct ip6_ext *)p)->ip6e_len + 1) << 3;
hdrtype = (int)((struct ip6_ext *)p)->ip6e_nxt;
if (tlen < hdrlen) {
error = EINVAL;
goto bad;
}
optend = p + hdrlen;
/*
* ICV calculation for the options header including all
* options. This part is a little tricky since there are
* two type of options; mutable and immutable. Our approach
* is to calculate ICV for a consecutive immutable options
* at once. Here is an example. In the following figure,
* suppose that we've calculated ICV from the top of the
* header to MutableOpt1, which is a mutable option.
* lastp points to the end of MutableOpt1. Some immutable
* options follows MutableOpt1, and we encounter a new
* mutable option; MutableOpt2. optp points to the head
* of MutableOpt2. In this situation, uncalculated immutable
* field is the field from lastp to optp+2 (note that the
* type and the length fields are considered as immutable
* even in a mutable option). So we first calculate ICV
* for the field as immutable, then calculate from optp+2
* to the end of MutableOpt2, whose length is optlen-2,
* where optlen is the length of MutableOpt2. Finally,
* lastp is updated to point to the end of MutableOpt2
* for further calculation. The updated point is shown as
* lastp' in the figure.
* <------ optlen ----->
* -----------+-------------------+---+---+-----------+
* MutableOpt1|ImmutableOptions...|typ|len|MutableOpt2|
* -----------+-------------------+---+---+-----------+
* ^ ^ ^
* lastp optp optp+2
* <---- optp + 2 - lastp -----><-optlen-2->
* ^
* lastp'
*/
for (optp = p + 2; optp < optend; optp += optlen) {
opt = optp[0];
if (opt == IP6OPT_PAD1) {
optlen = 1;
} else {
if (optp + 2 > optend) {
error = EINVAL; /* malformed option */
goto bad;
}
optlen = optp[1] + 2;
if (opt & IP6OPT_MUTABLE) {
/*
* ICV calc. for the (consecutive)
* immutable field followd by the
* option.
*/
(algo->update)(&algos, lastp,
optp + 2 - lastp);
if (optlen - 2 > ZEROBUFLEN) {
error = EINVAL; /* XXX */
goto bad;
}
/*
* ICV calc. for the mutable
* option using an all-0 buffer.
*/
(algo->update)(&algos, zerobuf,
optlen - 2);
lastp = optp + optlen;
}
}
}
/*
* Wrap up the calulation; compute ICV for the consecutive
* immutable options at the end of the header(if any).
*/
(algo->update)(&algos, lastp, p + hdrlen - lastp);
advancewidth = hdrlen;
break;
}
case IPPROTO_ROUTING:
{
/*
* For an input packet, we can just calculate `as is'.
* For an output packet, we assume ip6_output have already
* made packet how it will be received at the final destination.
* So we'll only check if the header is malformed.
*/
int hdrlen;
tlen = m->m_len - (p - mtod(m, u_char *));
/* We assume all the options is contained in a single mbuf */
if (tlen < sizeof(struct ip6_ext)) {
error = EINVAL;
goto bad;
}
hdrlen = (((struct ip6_ext *)p)->ip6e_len + 1) << 3;
hdrtype = (int)((struct ip6_ext *)p)->ip6e_nxt;
if (tlen < hdrlen) {
error = EINVAL;
goto bad;
}
advancewidth = hdrlen;
(algo->update)(&algos, p, hdrlen);
break;
}
default:
printf("ah6_calccksum: unexpected hdrtype=%x; "
"treating rest as payload\n", hdrtype);
/*fall through*/
case IPPROTO_ICMP:
case IPPROTO_IGMP:
case IPPROTO_IPIP: /*?*/
case IPPROTO_IPV6:
case IPPROTO_ICMPV6:
case IPPROTO_UDP:
case IPPROTO_TCP:
case IPPROTO_ESP:
while (m) {
tlen = m->m_len - (p - mtod(m, u_char *));
(algo->update)(&algos, p, tlen);
m = m->m_next;
p = m ? mtod(m, u_char *) : NULL;
}
advancewidth = 0; /*loop finished*/
break;
}
if (advancewidth) {
/* is it safe? */
while (m && advancewidth) {
tlen = m->m_len - (p - mtod(m, u_char *));
if (advancewidth < tlen) {
p += advancewidth;
advancewidth = 0;
} else {
advancewidth -= tlen;
m = m->m_next;
if (m)
p = mtod(m, u_char *);
else {
printf("ERR: hit the end-of-mbuf...\n");
p = NULL;
}
}
}
if (m)
goto again;
}
/* for HMAC algorithms... */
(algo->result)(&algos, &sumbuf[0]);
bcopy(&sumbuf[0], ahdat, (*algo->sumsiz)(sav));
return(0);
bad:
return(error);
}
#endif
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