blob: 0e84dc4aebadd17885f36de9654be3f6549a0831 [file] [log] [blame] [raw]
/*
* Simple ISAKMP transparent proxy for in-kernel use. For use with the NAT
* code.
*
* $Id$
*
*/
#define IPF_IPSEC_PROXY
int ippr_ipsec_init __P((void));
int ippr_ipsec_new __P((fr_info_t *, ip_t *, ap_session_t *, nat_t *));
void ippr_ipsec_del __P((ap_session_t *));
int ippr_ipsec_out __P((fr_info_t *, ip_t *, ap_session_t *, nat_t *));
int ippr_ipsec_match __P((fr_info_t *, ap_session_t *, nat_t *));
static frentry_t ipsecfr;
static char ipsec_buffer[1500];
/*
* RCMD application proxy initialization.
*/
int ippr_ipsec_init()
{
bzero((char *)&ipsecfr, sizeof(ipsecfr));
ipsecfr.fr_ref = 1;
ipsecfr.fr_flags = FR_OUTQUE|FR_PASS|FR_QUICK|FR_KEEPSTATE;
return 0;
}
/*
* Setup for a new IPSEC proxy.
*/
int ippr_ipsec_new(fin, ip, aps, nat)
fr_info_t *fin;
ip_t *ip;
ap_session_t *aps;
nat_t *nat;
{
ipsec_pxy_t *ipsec;
fr_info_t fi;
ipnat_t *ipn;
char *ptr;
int p, off, dlen;
mb_t *m;
bzero(ipsec_buffer, sizeof(ipsec_buffer));
off = fin->fin_hlen + sizeof(udphdr_t);
#ifdef _KERNEL
# if SOLARIS
m = fin->fin_qfm;
dlen = msgdsize(m) - off;
if (dlen < 16)
return -1;
copyout_mblk(m, off, MIN(sizeof(ipsec_buffer), dlen), ipsec_buffer);
# else
m = *(mb_t **)fin->fin_mp;
dlen = mbufchainlen(m) - off;
if (dlen < 16)
return -1;
m_copydata(m, off, MIN(sizeof(ipsec_buffer), dlen), ipsec_buffer);
# endif
#else
m = *(mb_t **)fin->fin_mp;
dlen = ip->ip_len - off;
ptr = (char *)m;
ptr += off;
bcopy(ptr, ipsec_buffer, MIN(sizeof(ipsec_buffer), dlen));
#endif
/*
* Because _new() gets called from nat_new(), ipf_nat is held with a
* write lock so pass rw=1 to nat_outlookup().
*/
if (nat_outlookup(fin, 0, IPPROTO_ESP, nat->nat_inip,
ip->ip_dst, 1) != NULL)
return -1;
aps->aps_psiz = sizeof(*ipsec);
KMALLOCS(aps->aps_data, ipsec_pxy_t *, sizeof(*ipsec));
if (aps->aps_data == NULL)
return -1;
ipsec = aps->aps_data;
bzero((char *)ipsec, sizeof(*ipsec));
/*
* Create NAT rule against which the tunnel/transport mapping is
* created. This is required because the current NAT rule does not
* describe ESP but UDP instead.
*/
ipn = &ipsec->ipsc_rule;
ipn->in_ifp = fin->fin_ifp;
ipn->in_apr = NULL;
ipn->in_use = 1;
ipn->in_hits = 1;
ipn->in_nip = ntohl(nat->nat_outip.s_addr);
ipn->in_ippip = 1;
ipn->in_inip = nat->nat_inip.s_addr;
ipn->in_inmsk = 0xffffffff;
ipn->in_outip = nat->nat_outip.s_addr;
ipn->in_outmsk = 0xffffffff;
ipn->in_srcip = fin->fin_saddr;
ipn->in_srcmsk = 0xffffffff;
ipn->in_redir = NAT_MAP;
bcopy(nat->nat_ptr->in_ifname, ipn->in_ifname, sizeof(ipn->in_ifname));
ipn->in_p = IPPROTO_ESP;
bcopy((char *)fin, (char *)&fi, sizeof(fi));
fi.fin_fi.fi_p = IPPROTO_ESP;
fi.fin_fr = &ipsecfr;
fi.fin_data[0] = 0;
fi.fin_data[1] = 0;
p = ip->ip_p;
ip->ip_p = IPPROTO_ESP;
fi.fin_fl &= ~FI_TCPUDP;
ptr = ipsec_buffer;
bcopy(ptr, ipsec->ipsc_icookie, sizeof(ipsec_cookie_t));
ptr += sizeof(ipsec_cookie_t);
bcopy(ptr, ipsec->ipsc_rcookie, sizeof(ipsec_cookie_t));
/*
* The responder cookie should only be non-zero if the initiator
* cookie is non-zero. Therefore, it is safe to assume(!) that the
* cookies are both set after copying if the responder is non-zero.
*/
if ((ipsec->ipsc_rcookie[0]|ipsec->ipsc_rcookie[1]) != 0)
ipsec->ipsc_rckset = 1;
else
nat->nat_age = 60; /* 30 seconds */
ipsec->ipsc_nat = nat_new(&fi, ip, ipn, &ipsec->ipsc_nat, FI_IGNOREPKT,
NAT_OUTBOUND);
if (ipsec->ipsc_nat != NULL) {
fi.fin_data[0] = 0;
fi.fin_data[1] = 0;
ipsec->ipsc_state = fr_addstate(ip, &fi, &ipsec->ipsc_state,
FI_IGNOREPKT|FI_NORULE);
}
ip->ip_p = p;
return 0;
}
/*
* For outgoing IKE packets. refresh timeouts for NAT & stat entries, if
* we can. If they have disappeared, recreate them.
*/
int ippr_ipsec_out(fin, ip, aps, nat)
fr_info_t *fin;
ip_t *ip;
ap_session_t *aps;
nat_t *nat;
{
ipsec_pxy_t *ipsec;
fr_info_t fi;
int p;
bcopy((char *)fin, (char *)&fi, sizeof(fi));
fi.fin_fi.fi_p = IPPROTO_ESP;
fi.fin_fr = &ipsecfr;
fi.fin_data[0] = 0;
fi.fin_data[1] = 0;
p = ip->ip_p;
ip->ip_p = IPPROTO_ESP;
fi.fin_fl &= ~FI_TCPUDP;
ipsec = aps->aps_data;
if (ipsec != NULL) {
/*
* Update NAT timeout/create NAT if missing.
*/
if (ipsec->ipsc_rckset == 0)
nat->nat_age = 60; /* 30 seconds */
if (ipsec->ipsc_nat != NULL)
ipsec->ipsc_nat->nat_age = nat->nat_age;
else
ipsec->ipsc_nat = nat_new(&fi, ip, &ipsec->ipsc_rule,
&ipsec->ipsc_nat,
FI_IGNOREPKT, NAT_OUTBOUND);
/*
* Update state timeout/create state if missing.
*/
READ_ENTER(&ipf_state);
if (ipsec->ipsc_state != NULL) {
ipsec->ipsc_state->is_age = nat->nat_age;
RWLOCK_EXIT(&ipf_state);
} else {
RWLOCK_EXIT(&ipf_state);
fi.fin_data[0] = 0;
fi.fin_data[1] = 0;
ipsec->ipsc_state = fr_addstate(ip, &fi,
&ipsec->ipsc_state,
FI_IGNOREPKT|FI_NORULE);
}
}
ip->ip_p = p;
return 0;
}
/*
* This extends the NAT matching to be based on the cookies associated with
* a session and found at the front of IKE packets. The cookies are always
* in the same order (not reversed depending on packet flow direction as with
* UDP/TCP port numbers).
*/
int ippr_ipsec_match(fin, aps, nat)
fr_info_t *fin;
ap_session_t *aps;
nat_t *nat;
{
ipsec_pxy_t *ipsec;
u_32_t cookies[4];
mb_t *m;
int off;
if ((fin->fin_dlen < sizeof(cookies)) || (fin->fin_fl & FI_FRAG))
return -1;
ipsec = aps->aps_data;
off = fin->fin_hlen + sizeof(udphdr_t);
#ifdef _KERNEL
# if SOLARIS
m = fin->fin_qfm;
copyout_mblk(m, off, sizeof(cookies), (char *)cookies);
# else
m = *(mb_t **)fin->fin_mp;
m_copydata(m, off, sizeof(cookies), (char *)cookies);
# endif
#else
m = *(mb_t **)fin->fin_mp;
bcopy((char *)m + off, cookies, sizeof(cookies));
#endif
if ((cookies[0] != ipsec->ipsc_icookie[0]) ||
(cookies[1] != ipsec->ipsc_icookie[1]))
return -1;
if (ipsec->ipsc_rckset == 0) {
if ((cookies[2]|cookies[3]) == 0) {
nat->nat_age = 60; /* 30 seconds */
return 0;
}
ipsec->ipsc_rckset = 1;
ipsec->ipsc_rcookie[0] = cookies[2];
ipsec->ipsc_rcookie[1] = cookies[3];
return 0;
}
if ((cookies[2] != ipsec->ipsc_rcookie[0]) ||
(cookies[3] != ipsec->ipsc_rcookie[1]))
return -1;
return 0;
}
/*
* clean up after ourselves.
*/
void ippr_ipsec_del(aps)
ap_session_t *aps;
{
ipsec_pxy_t *ipsec;
ipsec = aps->aps_data;
if (ipsec != NULL) {
/*
* Don't delete it from here, just schedule it to be
* deleted ASAP.
*/
if (ipsec->ipsc_nat != NULL) {
ipsec->ipsc_nat->nat_age = 1;
ipsec->ipsc_nat->nat_ptr = NULL;
}
READ_ENTER(&ipf_state);
if (ipsec->ipsc_state != NULL)
ipsec->ipsc_state->is_age = 1;
RWLOCK_EXIT(&ipf_state);
ipsec->ipsc_state = NULL;
ipsec->ipsc_nat = NULL;
}
}