uint8_t convert_state(struct pfsync_state *state, struct pf_nattrack *node) {
struct pfsync_state_key *orig, *trans;
uint8_t src, dst;
if (state->direction == PF_OUT) {
src = 1; dst = 0;
orig = &state->key[PF_SK_STACK];
trans = &state->key[PF_SK_WIRE];
} else {
src = 0; dst = 1;
orig = &state->key[PF_SK_WIRE];
trans = &state->key[PF_SK_STACK];
}
// check if it is a NAT:
// key_wire == key_stack --> NO NAT
// key_wire != key_stack --> NAT
if (state->af != AF_INET ||
(PF_AEQ(&orig->addr[src], &trans->addr[src], state->af) &&
PF_AEQ(&orig->addr[dst], &trans->addr[dst], state->af) &&
orig->port[src] == trans->port[src] &&
orig->port[dst] == trans->port[dst])) {
//printf("NO_NAT!\n");
return 0;
}
memset(node, 0, sizeof(struct pf_nattrack));
node->c.osrc.v4 = orig->addr[src].v4;
node->c.tsrc.v4 = trans->addr[src].v4;
node->c.odst.v4 = orig->addr[dst].v4;
node->c.tdst.v4 = trans->addr[dst].v4;
node->c.osport = ntohs(orig->port[src]);
node->c.tsport = ntohs(trans->port[src]);
node->c.odport = ntohs(orig->port[dst]);
node->c.tdport = ntohs(trans->port[dst]);
node->af = state->af;
node->proto = state->proto;
node->duration = ntohl(state->creation) + ntohl(state->expire);
return 1;
}
static int
pf_get_sport(sa_family_t af, u_int8_t proto, struct pf_rule *r,
struct pf_addr *saddr, uint16_t sport, struct pf_addr *daddr,
uint16_t dport, struct pf_addr *naddr, uint16_t *nport, uint16_t low,
uint16_t high, struct pf_src_node **sn)
{
struct pf_state_key_cmp key;
struct pf_addr init_addr;
uint16_t cut;
bzero(&init_addr, sizeof(init_addr));
if (pf_map_addr(af, r, saddr, naddr, &init_addr, sn))
return (1);
if (proto == IPPROTO_ICMP) {
low = 1;
high = 65535;
}
bzero(&key, sizeof(key));
key.af = af;
key.proto = proto;
key.port[0] = dport;
PF_ACPY(&key.addr[0], daddr, key.af);
do {
PF_ACPY(&key.addr[1], naddr, key.af);
/*
* port search; start random, step;
* similar 2 portloop in in_pcbbind
*/
if (!(proto == IPPROTO_TCP || proto == IPPROTO_UDP ||
proto == IPPROTO_ICMP) || (low == 0 && high == 0)) {
/*
* XXX bug: icmp states don't use the id on both sides.
* (traceroute -I through nat)
*/
key.port[1] = sport;
if (pf_find_state_all(&key, PF_IN, NULL) == NULL) {
*nport = sport;
return (0);
}
} else if (low == high) {
key.port[1] = htons(low);
if (pf_find_state_all(&key, PF_IN, NULL) == NULL) {
*nport = htons(low);
return (0);
}
} else {
uint16_t tmp;
if (low > high) {
tmp = low;
low = high;
high = tmp;
}
/* low < high */
cut = htonl(arc4random()) % (1 + high - low) + low;
/* low <= cut <= high */
for (tmp = cut; tmp <= high; ++(tmp)) {
key.port[1] = htons(tmp);
if (pf_find_state_all(&key, PF_IN, NULL) ==
NULL) {
*nport = htons(tmp);
return (0);
}
}
for (tmp = cut - 1; tmp >= low; --(tmp)) {
key.port[1] = htons(tmp);
if (pf_find_state_all(&key, PF_IN, NULL) ==
NULL) {
*nport = htons(tmp);
return (0);
}
}
}
switch (r->rpool.opts & PF_POOL_TYPEMASK) {
case PF_POOL_RANDOM:
case PF_POOL_ROUNDROBIN:
if (pf_map_addr(af, r, saddr, naddr, &init_addr, sn))
return (1);
break;
case PF_POOL_NONE:
case PF_POOL_SRCHASH:
case PF_POOL_BITMASK:
default:
return (1);
}
} while (! PF_AEQ(&init_addr, naddr, af) );
return (1); /* none available */
}
int
pf_map_addr(sa_family_t af, struct pf_rule *r, struct pf_addr *saddr,
struct pf_addr *naddr, struct pf_addr *init_addr, struct pf_src_node **sn)
{
struct pf_pool *rpool = &r->rpool;
struct pf_addr *raddr = NULL, *rmask = NULL;
/* Try to find a src_node if none was given and this
is a sticky-address rule. */
if (*sn == NULL && r->rpool.opts & PF_POOL_STICKYADDR &&
(r->rpool.opts & PF_POOL_TYPEMASK) != PF_POOL_NONE)
*sn = pf_find_src_node(saddr, r, af, 0);
/* If a src_node was found or explicitly given and it has a non-zero
route address, use this address. A zeroed address is found if the
src node was created just a moment ago in pf_create_state and it
needs to be filled in with routing decision calculated here. */
if (*sn != NULL && !PF_AZERO(&(*sn)->raddr, af)) {
/* If the supplied address is the same as the current one we've
* been asked before, so tell the caller that there's no other
* address to be had. */
if (PF_AEQ(naddr, &(*sn)->raddr, af))
return (1);
PF_ACPY(naddr, &(*sn)->raddr, af);
if (V_pf_status.debug >= PF_DEBUG_MISC) {
printf("pf_map_addr: src tracking maps ");
pf_print_host(saddr, 0, af);
printf(" to ");
pf_print_host(naddr, 0, af);
printf("\n");
}
return (0);
}
/* Find the route using chosen algorithm. Store the found route
in src_node if it was given or found. */
if (rpool->cur->addr.type == PF_ADDR_NOROUTE)
return (1);
if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
switch (af) {
#ifdef INET
case AF_INET:
if (rpool->cur->addr.p.dyn->pfid_acnt4 < 1 &&
(rpool->opts & PF_POOL_TYPEMASK) !=
PF_POOL_ROUNDROBIN)
return (1);
raddr = &rpool->cur->addr.p.dyn->pfid_addr4;
rmask = &rpool->cur->addr.p.dyn->pfid_mask4;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (rpool->cur->addr.p.dyn->pfid_acnt6 < 1 &&
(rpool->opts & PF_POOL_TYPEMASK) !=
PF_POOL_ROUNDROBIN)
return (1);
raddr = &rpool->cur->addr.p.dyn->pfid_addr6;
rmask = &rpool->cur->addr.p.dyn->pfid_mask6;
break;
#endif /* INET6 */
}
} else if (rpool->cur->addr.type == PF_ADDR_TABLE) {
if ((rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_ROUNDROBIN)
return (1); /* unsupported */
} else {
raddr = &rpool->cur->addr.v.a.addr;
rmask = &rpool->cur->addr.v.a.mask;
}
switch (rpool->opts & PF_POOL_TYPEMASK) {
case PF_POOL_NONE:
PF_ACPY(naddr, raddr, af);
break;
case PF_POOL_BITMASK:
PF_POOLMASK(naddr, raddr, rmask, saddr, af);
break;
case PF_POOL_RANDOM:
if (init_addr != NULL && PF_AZERO(init_addr, af)) {
switch (af) {
#ifdef INET
case AF_INET:
rpool->counter.addr32[0] = htonl(arc4random());
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (rmask->addr32[3] != 0xffffffff)
rpool->counter.addr32[3] =
htonl(arc4random());
else
break;
if (rmask->addr32[2] != 0xffffffff)
rpool->counter.addr32[2] =
htonl(arc4random());
else
break;
if (rmask->addr32[1] != 0xffffffff)
rpool->counter.addr32[1] =
htonl(arc4random());
else
break;
if (rmask->addr32[0] != 0xffffffff)
rpool->counter.addr32[0] =
htonl(arc4random());
break;
#endif /* INET6 */
}
PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af);
PF_ACPY(init_addr, naddr, af);
} else {
PF_AINC(&rpool->counter, af);
PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af);
}
break;
case PF_POOL_SRCHASH:
{
unsigned char hash[16];
pf_hash(saddr, (struct pf_addr *)&hash, &rpool->key, af);
PF_POOLMASK(naddr, raddr, rmask, (struct pf_addr *)&hash, af);
break;
}
case PF_POOL_ROUNDROBIN:
{
struct pf_pooladdr *acur = rpool->cur;
/*
* XXXGL: in the round-robin case we need to store
* the round-robin machine state in the rule, thus
* forwarding thread needs to modify rule.
*
* This is done w/o locking, because performance is assumed
* more important than round-robin precision.
*
* In the simpliest case we just update the "rpool->cur"
* pointer. However, if pool contains tables or dynamic
* addresses, then "tblidx" is also used to store machine
* state. Since "tblidx" is int, concurrent access to it can't
* lead to inconsistence, only to lost of precision.
*
* Things get worse, if table contains not hosts, but
* prefixes. In this case counter also stores machine state,
* and for IPv6 address, counter can't be updated atomically.
* Probably, using round-robin on a table containing IPv6
* prefixes (or even IPv4) would cause a panic.
*/
if (rpool->cur->addr.type == PF_ADDR_TABLE) {
if (!pfr_pool_get(rpool->cur->addr.p.tbl,
&rpool->tblidx, &rpool->counter, af))
goto get_addr;
} else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
if (!pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt,
&rpool->tblidx, &rpool->counter, af))
goto get_addr;
} else if (pf_match_addr(0, raddr, rmask, &rpool->counter, af))
goto get_addr;
try_next:
if (TAILQ_NEXT(rpool->cur, entries) == NULL)
rpool->cur = TAILQ_FIRST(&rpool->list);
else
rpool->cur = TAILQ_NEXT(rpool->cur, entries);
if (rpool->cur->addr.type == PF_ADDR_TABLE) {
rpool->tblidx = -1;
if (pfr_pool_get(rpool->cur->addr.p.tbl,
&rpool->tblidx, &rpool->counter, af)) {
/* table contains no address of type 'af' */
if (rpool->cur != acur)
goto try_next;
return (1);
}
} else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
rpool->tblidx = -1;
if (pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt,
&rpool->tblidx, &rpool->counter, af)) {
/* table contains no address of type 'af' */
if (rpool->cur != acur)
goto try_next;
return (1);
}
} else {
raddr = &rpool->cur->addr.v.a.addr;
rmask = &rpool->cur->addr.v.a.mask;
PF_ACPY(&rpool->counter, raddr, af);
}
get_addr:
PF_ACPY(naddr, &rpool->counter, af);
if (init_addr != NULL && PF_AZERO(init_addr, af))
PF_ACPY(init_addr, naddr, af);
PF_AINC(&rpool->counter, af);
break;
}
}
if (*sn != NULL)
PF_ACPY(&(*sn)->raddr, naddr, af);
if (V_pf_status.debug >= PF_DEBUG_MISC &&
(rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) {
printf("pf_map_addr: selected address ");
pf_print_host(naddr, 0, af);
printf("\n");
}
return (0);
}
int
pf_get_sport(struct pf_pdesc *pd, struct pf_rule *r,
struct pf_addr *naddr, u_int16_t *nport, u_int16_t low, u_int16_t high,
struct pf_src_node **sn)
{
struct pf_state_key_cmp key;
struct pf_addr init_addr;
u_int16_t cut;
bzero(&init_addr, sizeof(init_addr));
if (pf_map_addr(pd->naf, r, &pd->nsaddr, naddr, &init_addr, sn, &r->nat,
PF_SN_NAT))
return (1);
if (pd->proto == IPPROTO_ICMP || pd->proto == IPPROTO_ICMPV6) {
if (pd->ndport == htons(ICMP6_ECHO_REQUEST) ||
pd->ndport == htons(ICMP_ECHO)) {
low = 1;
high = 65535;
} else
return (0); /* Don't try to modify non-echo ICMP */
}
do {
key.af = pd->naf;
key.proto = pd->proto;
key.rdomain = pd->rdomain;
PF_ACPY(&key.addr[0], &pd->ndaddr, key.af);
PF_ACPY(&key.addr[1], naddr, key.af);
key.port[0] = pd->ndport;
/*
* port search; start random, step;
* similar 2 portloop in in_pcbbind
*/
if (!(pd->proto == IPPROTO_TCP || pd->proto == IPPROTO_UDP ||
pd->proto == IPPROTO_ICMP || pd->proto == IPPROTO_ICMPV6)) {
/* XXX bug: icmp states dont use the id on both
* XXX sides (traceroute -I through nat) */
key.port[1] = pd->nsport;
if (pf_find_state_all(&key, PF_IN, NULL) == NULL) {
*nport = pd->nsport;
return (0);
}
} else if (low == 0 && high == 0) {
key.port[1] = pd->nsport;
if (pf_find_state_all(&key, PF_IN, NULL) == NULL) {
*nport = pd->nsport;
return (0);
}
} else if (low == high) {
key.port[1] = htons(low);
if (pf_find_state_all(&key, PF_IN, NULL) == NULL) {
*nport = htons(low);
return (0);
}
} else {
u_int16_t tmp;
if (low > high) {
tmp = low;
low = high;
high = tmp;
}
/* low < high */
cut = arc4random_uniform(1 + high - low) + low;
/* low <= cut <= high */
for (tmp = cut; tmp <= high; ++(tmp)) {
key.port[1] = htons(tmp);
if (pf_find_state_all(&key, PF_IN, NULL) ==
NULL && !in_baddynamic(tmp, pd->proto)) {
*nport = htons(tmp);
return (0);
}
}
for (tmp = cut - 1; tmp >= low; --(tmp)) {
key.port[1] = htons(tmp);
if (pf_find_state_all(&key, PF_IN, NULL) ==
NULL && !in_baddynamic(tmp, pd->proto)) {
*nport = htons(tmp);
return (0);
}
}
}
switch (r->nat.opts & PF_POOL_TYPEMASK) {
case PF_POOL_RANDOM:
case PF_POOL_ROUNDROBIN:
case PF_POOL_LEASTSTATES:
/*
* pick a different source address since we're out
* of free port choices for the current one.
*/
if (pf_map_addr(pd->naf, r, &pd->nsaddr, naddr,
&init_addr, sn, &r->nat, PF_SN_NAT))
return (1);
break;
case PF_POOL_NONE:
case PF_POOL_SRCHASH:
case PF_POOL_BITMASK:
default:
return (1);
}
} while (! PF_AEQ(&init_addr, naddr, pd->naf) );
return (1); /* none available */
}
int
pf_get_sport(sa_family_t af, u_int8_t proto, struct pf_rule *r,
struct pf_addr *saddr, struct pf_addr *daddr, u_int16_t dport,
struct pf_addr *naddr, u_int16_t *nport, u_int16_t low, u_int16_t high,
struct pf_src_node **sn, int rdomain)
{
struct pf_state_key_cmp key;
struct pf_addr init_addr;
u_int16_t cut;
bzero(&init_addr, sizeof(init_addr));
if (pf_map_addr(af, r, saddr, naddr, &init_addr, sn, &r->nat,
PF_SN_NAT))
return (1);
if (proto == IPPROTO_ICMP || proto == IPPROTO_ICMPV6) {
if (dport == htons(ICMP6_ECHO_REQUEST) ||
dport == htons(ICMP_ECHO)) {
low = 1;
high = 65535;
} else
return (0); /* Don't try to modify non-echo ICMP */
}
do {
key.af = af;
key.proto = proto;
key.rdomain = rdomain;
PF_ACPY(&key.addr[1], daddr, key.af);
PF_ACPY(&key.addr[0], naddr, key.af);
key.port[1] = dport;
/*
* port search; start random, step;
* similar 2 portloop in in_pcbbind
*/
if (!(proto == IPPROTO_TCP || proto == IPPROTO_UDP ||
proto == IPPROTO_ICMP)) {
/* XXX bug icmp states dont use the id on both sides */
key.port[0] = dport;
if (pf_find_state_all(&key, PF_IN, NULL) == NULL)
return (0);
} else if (low == 0 && high == 0) {
key.port[0] = *nport;
if (pf_find_state_all(&key, PF_IN, NULL) == NULL)
return (0);
} else if (low == high) {
key.port[0] = htons(low);
if (pf_find_state_all(&key, PF_IN, NULL) == NULL) {
*nport = htons(low);
return (0);
}
} else {
u_int16_t tmp;
if (low > high) {
tmp = low;
low = high;
high = tmp;
}
/* low < high */
cut = arc4random_uniform(1 + high - low) + low;
/* low <= cut <= high */
for (tmp = cut; tmp <= high; ++(tmp)) {
key.port[0] = htons(tmp);
if (pf_find_state_all(&key, PF_IN, NULL) ==
NULL && !in_baddynamic(tmp, proto)) {
*nport = htons(tmp);
return (0);
}
}
for (tmp = cut - 1; tmp >= low; --(tmp)) {
key.port[0] = htons(tmp);
if (pf_find_state_all(&key, PF_IN, NULL) ==
NULL && !in_baddynamic(tmp, proto)) {
*nport = htons(tmp);
return (0);
}
}
}
switch (r->nat.opts & PF_POOL_TYPEMASK) {
case PF_POOL_RANDOM:
case PF_POOL_ROUNDROBIN:
if (pf_map_addr(af, r, saddr, naddr, &init_addr, sn,
&r->nat, PF_SN_NAT))
return (1);
break;
case PF_POOL_NONE:
case PF_POOL_SRCHASH:
case PF_POOL_BITMASK:
default:
return (1);
}
} while (! PF_AEQ(&init_addr, naddr, af) );
return (1); /* none available */
}
