/
nat.c
1188 lines (1063 loc) · 27.7 KB
/
nat.c
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/*-
* Copyright (c) 2002-2003 Luigi Rizzo
* Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp
* Copyright (c) 1994 Ugen J.S.Antsilevich
*
* Idea and grammar partially left from:
* Copyright (c) 1993 Daniel Boulet
*
* Redistribution and use in source forms, with and without modification,
* are permitted provided that this entire comment appears intact.
*
* Redistribution in binary form may occur without any restrictions.
* Obviously, it would be nice if you gave credit where credit is due
* but requiring it would be too onerous.
*
* This software is provided ``AS IS'' without any warranties of any kind.
*
* NEW command line interface for IP firewall facility
*
* In-kernel nat support
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include "ipfw2.h"
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/route.h> /* def. of struct route */
#include <netinet/in.h>
#include <netinet/ip_fw.h>
#include <arpa/inet.h>
#include <alias.h>
typedef int (nat_cb_t)(struct nat44_cfg_nat *cfg, void *arg);
static void nat_show_cfg(struct nat44_cfg_nat *n, void *arg);
static void nat_show_log(struct nat44_cfg_nat *n, void *arg);
static int nat_show_data(struct nat44_cfg_nat *cfg, void *arg);
static int natname_cmp(const void *a, const void *b);
static int nat_foreach(nat_cb_t *f, void *arg, int sort);
static int nat_get_cmd(char *name, uint16_t cmd, ipfw_obj_header **ooh);
static struct _s_x nat_params[] = {
{ "ip", TOK_IP },
{ "if", TOK_IF },
{ "log", TOK_ALOG },
{ "deny_in", TOK_DENY_INC },
{ "same_ports", TOK_SAME_PORTS },
{ "unreg_only", TOK_UNREG_ONLY },
{ "unreg_cgn", TOK_UNREG_CGN },
{ "skip_global", TOK_SKIP_GLOBAL },
{ "reset", TOK_RESET_ADDR },
{ "reverse", TOK_ALIAS_REV },
{ "proxy_only", TOK_PROXY_ONLY },
{ "port_range", TOK_PORT_ALIAS },
{ "redirect_addr", TOK_REDIR_ADDR },
{ "redirect_port", TOK_REDIR_PORT },
{ "redirect_proto", TOK_REDIR_PROTO },
{ NULL, 0 } /* terminator */
};
/*
* Search for interface with name "ifn", and fill n accordingly:
*
* n->ip ip address of interface "ifn"
* n->if_name copy of interface name "ifn"
*/
static void
set_addr_dynamic(const char *ifn, struct nat44_cfg_nat *n)
{
size_t needed;
int mib[6];
char *buf, *lim, *next;
struct if_msghdr *ifm;
struct ifa_msghdr *ifam;
struct sockaddr_dl *sdl;
struct sockaddr_in *sin;
int ifIndex;
mib[0] = CTL_NET;
mib[1] = PF_ROUTE;
mib[2] = 0;
mib[3] = AF_INET;
mib[4] = NET_RT_IFLIST;
mib[5] = 0;
/*
* Get interface data.
*/
if (sysctl(mib, 6, NULL, &needed, NULL, 0) == -1)
err(1, "iflist-sysctl-estimate");
buf = safe_calloc(1, needed);
if (sysctl(mib, 6, buf, &needed, NULL, 0) == -1)
err(1, "iflist-sysctl-get");
lim = buf + needed;
/*
* Loop through interfaces until one with
* given name is found. This is done to
* find correct interface index for routing
* message processing.
*/
ifIndex = 0;
next = buf;
while (next < lim) {
ifm = (struct if_msghdr *)next;
next += ifm->ifm_msglen;
if (ifm->ifm_version != RTM_VERSION) {
if (g_co.verbose)
warnx("routing message version %d "
"not understood", ifm->ifm_version);
continue;
}
if (ifm->ifm_type == RTM_IFINFO) {
sdl = (struct sockaddr_dl *)(ifm + 1);
if (strlen(ifn) == sdl->sdl_nlen &&
strncmp(ifn, sdl->sdl_data, sdl->sdl_nlen) == 0) {
ifIndex = ifm->ifm_index;
break;
}
}
}
if (!ifIndex)
errx(1, "unknown interface name %s", ifn);
/*
* Get interface address.
*/
sin = NULL;
while (next < lim) {
ifam = (struct ifa_msghdr *)next;
next += ifam->ifam_msglen;
if (ifam->ifam_version != RTM_VERSION) {
if (g_co.verbose)
warnx("routing message version %d "
"not understood", ifam->ifam_version);
continue;
}
if (ifam->ifam_type != RTM_NEWADDR)
break;
if (ifam->ifam_addrs & RTA_IFA) {
int i;
char *cp = (char *)(ifam + 1);
for (i = 1; i < RTA_IFA; i <<= 1) {
if (ifam->ifam_addrs & i)
cp += SA_SIZE((struct sockaddr *)cp);
}
if (((struct sockaddr *)cp)->sa_family == AF_INET) {
sin = (struct sockaddr_in *)cp;
break;
}
}
}
if (sin == NULL)
n->ip.s_addr = htonl(INADDR_ANY);
else
n->ip = sin->sin_addr;
strncpy(n->if_name, ifn, IF_NAMESIZE);
free(buf);
}
/*
* XXX - The following functions, macros and definitions come from natd.c:
* it would be better to move them outside natd.c, in a file
* (redirect_support.[ch]?) shared by ipfw and natd, but for now i can live
* with it.
*/
/*
* Definition of a port range, and macros to deal with values.
* FORMAT: HI 16-bits == first port in range, 0 == all ports.
* LO 16-bits == number of ports in range
* NOTES: - Port values are not stored in network byte order.
*/
#define port_range u_long
#define GETLOPORT(x) ((x) >> 0x10)
#define GETNUMPORTS(x) ((x) & 0x0000ffff)
#define GETHIPORT(x) (GETLOPORT((x)) + GETNUMPORTS((x)))
/* Set y to be the low-port value in port_range variable x. */
#define SETLOPORT(x,y) ((x) = ((x) & 0x0000ffff) | ((y) << 0x10))
/* Set y to be the number of ports in port_range variable x. */
#define SETNUMPORTS(x,y) ((x) = ((x) & 0xffff0000) | (y))
static void
StrToAddr (const char* str, struct in_addr* addr)
{
struct hostent* hp;
if (inet_aton (str, addr))
return;
hp = gethostbyname (str);
if (!hp)
errx (1, "unknown host %s", str);
memcpy (addr, hp->h_addr, sizeof (struct in_addr));
}
static int
StrToPortRange (const char* str, const char* proto, port_range *portRange)
{
char* sep;
struct servent* sp;
char* end;
u_short loPort;
u_short hiPort;
/* First see if this is a service, return corresponding port if so. */
sp = getservbyname (str,proto);
if (sp) {
SETLOPORT(*portRange, ntohs(sp->s_port));
SETNUMPORTS(*portRange, 1);
return 0;
}
/* Not a service, see if it's a single port or port range. */
sep = strchr (str, '-');
if (sep == NULL) {
SETLOPORT(*portRange, strtol(str, &end, 10));
if (end != str) {
/* Single port. */
SETNUMPORTS(*portRange, 1);
return 0;
}
/* Error in port range field. */
errx (EX_DATAERR, "%s/%s: unknown service", str, proto);
}
/* Port range, get the values and sanity check. */
sscanf (str, "%hu-%hu", &loPort, &hiPort);
SETLOPORT(*portRange, loPort);
SETNUMPORTS(*portRange, 0); /* Error by default */
if (loPort <= hiPort)
SETNUMPORTS(*portRange, hiPort - loPort + 1);
if (GETNUMPORTS(*portRange) == 0)
errx (EX_DATAERR, "invalid port range %s", str);
return 0;
}
static int
StrToProto (const char* str)
{
if (!strcmp (str, "tcp"))
return IPPROTO_TCP;
if (!strcmp (str, "udp"))
return IPPROTO_UDP;
if (!strcmp (str, "sctp"))
return IPPROTO_SCTP;
errx (EX_DATAERR, "unknown protocol %s. Expected sctp, tcp or udp", str);
}
static int
StrToAddrAndPortRange (const char* str, struct in_addr* addr, char* proto,
port_range *portRange)
{
char* ptr;
ptr = strchr (str, ':');
if (!ptr)
errx (EX_DATAERR, "%s is missing port number", str);
*ptr = '\0';
++ptr;
StrToAddr (str, addr);
return StrToPortRange (ptr, proto, portRange);
}
/* End of stuff taken from natd.c. */
/*
* The next 3 functions add support for the addr, port and proto redirect and
* their logic is loosely based on SetupAddressRedirect(), SetupPortRedirect()
* and SetupProtoRedirect() from natd.c.
*
* Every setup_* function fills at least one redirect entry
* (struct nat44_cfg_redir) and zero or more server pool entry
* (struct nat44_cfg_spool) in buf.
*
* The format of data in buf is:
*
* nat44_cfg_nat nat44_cfg_redir nat44_cfg_spool ...... nat44_cfg_spool
*
* ------------------------------------- ------------
* | | .....X ..... | | | | .....
* ------------------------------------- ...... ------------
* ^
* spool_cnt n=0 ...... n=(X-1)
*
* len points to the amount of available space in buf
* space counts the memory consumed by every function
*
* XXX - Every function get all the argv params so it
* has to check, in optional parameters, that the next
* args is a valid option for the redir entry and not
* another token. Only redir_port and redir_proto are
* affected by this.
*/
static int
estimate_redir_addr(int *ac, char ***av)
{
size_t space = sizeof(struct nat44_cfg_redir);
char *sep = **av;
u_int c = 0;
(void)ac; /* UNUSED */
while ((sep = strchr(sep, ',')) != NULL) {
c++;
sep++;
}
if (c > 0)
c++;
space += c * sizeof(struct nat44_cfg_spool);
return (space);
}
static int
setup_redir_addr(char *buf, int *ac, char ***av)
{
struct nat44_cfg_redir *r;
char *sep;
size_t space;
r = (struct nat44_cfg_redir *)buf;
r->mode = REDIR_ADDR;
/* Skip nat44_cfg_redir at beginning of buf. */
buf = &buf[sizeof(struct nat44_cfg_redir)];
space = sizeof(struct nat44_cfg_redir);
/* Extract local address. */
if (strchr(**av, ',') != NULL) {
struct nat44_cfg_spool *spool;
/* Setup LSNAT server pool. */
r->laddr.s_addr = INADDR_NONE;
sep = strtok(**av, ",");
while (sep != NULL) {
spool = (struct nat44_cfg_spool *)buf;
space += sizeof(struct nat44_cfg_spool);
StrToAddr(sep, &spool->addr);
spool->port = ~0;
r->spool_cnt++;
/* Point to the next possible nat44_cfg_spool. */
buf = &buf[sizeof(struct nat44_cfg_spool)];
sep = strtok(NULL, ",");
}
} else
StrToAddr(**av, &r->laddr);
(*av)++; (*ac)--;
/* Extract public address. */
StrToAddr(**av, &r->paddr);
(*av)++; (*ac)--;
return (space);
}
static int
estimate_redir_port(int *ac, char ***av)
{
size_t space = sizeof(struct nat44_cfg_redir);
char *sep = **av;
u_int c = 0;
(void)ac; /* UNUSED */
while ((sep = strchr(sep, ',')) != NULL) {
c++;
sep++;
}
if (c > 0)
c++;
space += c * sizeof(struct nat44_cfg_spool);
return (space);
}
static int
setup_redir_port(char *buf, int *ac, char ***av)
{
struct nat44_cfg_redir *r;
char *sep, *protoName, *lsnat = NULL;
size_t space;
u_short numLocalPorts;
port_range portRange;
numLocalPorts = 0;
r = (struct nat44_cfg_redir *)buf;
r->mode = REDIR_PORT;
/* Skip nat44_cfg_redir at beginning of buf. */
buf = &buf[sizeof(struct nat44_cfg_redir)];
space = sizeof(struct nat44_cfg_redir);
/*
* Extract protocol.
*/
r->proto = StrToProto(**av);
protoName = **av;
(*av)++; (*ac)--;
/*
* Extract local address.
*/
if (strchr(**av, ',') != NULL) {
r->laddr.s_addr = INADDR_NONE;
r->lport = ~0;
numLocalPorts = 1;
lsnat = **av;
} else {
/*
* The sctp nat does not allow the port numbers to be mapped to
* new port numbers. Therefore, no ports are to be specified
* in the target port field.
*/
if (r->proto == IPPROTO_SCTP) {
if (strchr(**av, ':'))
errx(EX_DATAERR, "redirect_port:"
"port numbers do not change in sctp, so do "
"not specify them as part of the target");
else
StrToAddr(**av, &r->laddr);
} else {
if (StrToAddrAndPortRange(**av, &r->laddr, protoName,
&portRange) != 0)
errx(EX_DATAERR, "redirect_port: "
"invalid local port range");
r->lport = GETLOPORT(portRange);
numLocalPorts = GETNUMPORTS(portRange);
}
}
(*av)++; (*ac)--;
/*
* Extract public port and optionally address.
*/
if (strchr(**av, ':') != NULL) {
if (StrToAddrAndPortRange(**av, &r->paddr, protoName,
&portRange) != 0)
errx(EX_DATAERR, "redirect_port: "
"invalid public port range");
} else {
r->paddr.s_addr = INADDR_ANY;
if (StrToPortRange(**av, protoName, &portRange) != 0)
errx(EX_DATAERR, "redirect_port: "
"invalid public port range");
}
r->pport = GETLOPORT(portRange);
if (r->proto == IPPROTO_SCTP) { /* so the logic below still works */
numLocalPorts = GETNUMPORTS(portRange);
r->lport = r->pport;
}
r->pport_cnt = GETNUMPORTS(portRange);
(*av)++; (*ac)--;
/*
* Extract remote address and optionally port.
*/
/*
* NB: isdigit(**av) => we've to check that next parameter is really an
* option for this redirect entry, else stop here processing arg[cv].
*/
if (*ac != 0 && isdigit(***av)) {
if (strchr(**av, ':') != NULL) {
if (StrToAddrAndPortRange(**av, &r->raddr, protoName,
&portRange) != 0)
errx(EX_DATAERR, "redirect_port: "
"invalid remote port range");
} else {
SETLOPORT(portRange, 0);
SETNUMPORTS(portRange, 1);
StrToAddr(**av, &r->raddr);
}
(*av)++; (*ac)--;
} else {
SETLOPORT(portRange, 0);
SETNUMPORTS(portRange, 1);
r->raddr.s_addr = INADDR_ANY;
}
r->rport = GETLOPORT(portRange);
r->rport_cnt = GETNUMPORTS(portRange);
/*
* Make sure port ranges match up, then add the redirect ports.
*/
if (numLocalPorts != r->pport_cnt)
errx(EX_DATAERR, "redirect_port: "
"port ranges must be equal in size");
/* Remote port range is allowed to be '0' which means all ports. */
if (r->rport_cnt != numLocalPorts &&
(r->rport_cnt != 1 || r->rport != 0))
errx(EX_DATAERR, "redirect_port: remote port must"
"be 0 or equal to local port range in size");
/* Setup LSNAT server pool. */
if (lsnat != NULL) {
struct nat44_cfg_spool *spool;
sep = strtok(lsnat, ",");
while (sep != NULL) {
spool = (struct nat44_cfg_spool *)buf;
space += sizeof(struct nat44_cfg_spool);
/*
* The sctp nat does not allow the port numbers to
* be mapped to new port numbers. Therefore, no ports
* are to be specified in the target port field.
*/
if (r->proto == IPPROTO_SCTP) {
if (strchr (sep, ':')) {
errx(EX_DATAERR, "redirect_port:"
"port numbers do not change in "
"sctp, so do not specify them as "
"part of the target");
} else {
StrToAddr(sep, &spool->addr);
spool->port = r->pport;
}
} else {
if (StrToAddrAndPortRange(sep, &spool->addr,
protoName, &portRange) != 0)
errx(EX_DATAERR, "redirect_port:"
"invalid local port range");
if (GETNUMPORTS(portRange) != 1)
errx(EX_DATAERR, "redirect_port: "
"local port must be single in "
"this context");
spool->port = GETLOPORT(portRange);
}
r->spool_cnt++;
/* Point to the next possible nat44_cfg_spool. */
buf = &buf[sizeof(struct nat44_cfg_spool)];
sep = strtok(NULL, ",");
}
}
return (space);
}
static int
setup_redir_proto(char *buf, int *ac, char ***av)
{
struct nat44_cfg_redir *r;
struct protoent *protoent;
size_t space;
r = (struct nat44_cfg_redir *)buf;
r->mode = REDIR_PROTO;
/* Skip nat44_cfg_redir at beginning of buf. */
buf = &buf[sizeof(struct nat44_cfg_redir)];
space = sizeof(struct nat44_cfg_redir);
/*
* Extract protocol.
*/
protoent = getprotobyname(**av);
if (protoent == NULL)
errx(EX_DATAERR, "redirect_proto: unknown protocol %s", **av);
else
r->proto = protoent->p_proto;
(*av)++; (*ac)--;
/*
* Extract local address.
*/
StrToAddr(**av, &r->laddr);
(*av)++; (*ac)--;
/*
* Extract optional public address.
*/
if (*ac == 0) {
r->paddr.s_addr = INADDR_ANY;
r->raddr.s_addr = INADDR_ANY;
} else {
/* see above in setup_redir_port() */
if (isdigit(***av)) {
StrToAddr(**av, &r->paddr);
(*av)++; (*ac)--;
/*
* Extract optional remote address.
*/
/* see above in setup_redir_port() */
if (*ac != 0 && isdigit(***av)) {
StrToAddr(**av, &r->raddr);
(*av)++; (*ac)--;
}
}
}
return (space);
}
static void
nat_show_log(struct nat44_cfg_nat *n, void *arg __unused)
{
char *buf;
buf = (char *)(n + 1);
if (buf[0] != '\0')
printf("nat %s: %s\n", n->name, buf);
}
static void
nat_show_cfg(struct nat44_cfg_nat *n, void *arg __unused)
{
struct nat44_cfg_redir *t;
struct nat44_cfg_spool *s;
caddr_t buf;
struct protoent *p;
uint32_t cnt;
int i, off;
buf = (caddr_t)n;
off = sizeof(*n);
printf("ipfw nat %s config", n->name);
if (strlen(n->if_name) != 0)
printf(" if %s", n->if_name);
else if (n->ip.s_addr != 0)
printf(" ip %s", inet_ntoa(n->ip));
while (n->mode != 0) {
if (n->mode & PKT_ALIAS_LOG) {
printf(" log");
n->mode &= ~PKT_ALIAS_LOG;
} else if (n->mode & PKT_ALIAS_DENY_INCOMING) {
printf(" deny_in");
n->mode &= ~PKT_ALIAS_DENY_INCOMING;
} else if (n->mode & PKT_ALIAS_SAME_PORTS) {
printf(" same_ports");
n->mode &= ~PKT_ALIAS_SAME_PORTS;
} else if (n->mode & PKT_ALIAS_SKIP_GLOBAL) {
printf(" skip_global");
n->mode &= ~PKT_ALIAS_SKIP_GLOBAL;
} else if (n->mode & PKT_ALIAS_UNREGISTERED_ONLY) {
printf(" unreg_only");
n->mode &= ~PKT_ALIAS_UNREGISTERED_ONLY;
} else if (n->mode & PKT_ALIAS_UNREGISTERED_CGN) {
printf(" unreg_cgn");
n->mode &= ~PKT_ALIAS_UNREGISTERED_CGN;
} else if (n->mode & PKT_ALIAS_RESET_ON_ADDR_CHANGE) {
printf(" reset");
n->mode &= ~PKT_ALIAS_RESET_ON_ADDR_CHANGE;
} else if (n->mode & PKT_ALIAS_REVERSE) {
printf(" reverse");
n->mode &= ~PKT_ALIAS_REVERSE;
} else if (n->mode & PKT_ALIAS_PROXY_ONLY) {
printf(" proxy_only");
n->mode &= ~PKT_ALIAS_PROXY_ONLY;
}
}
/* Print all the redirect's data configuration. */
for (cnt = 0; cnt < n->redir_cnt; cnt++) {
t = (struct nat44_cfg_redir *)&buf[off];
off += sizeof(struct nat44_cfg_redir);
switch (t->mode) {
case REDIR_ADDR:
printf(" redirect_addr");
if (t->spool_cnt == 0)
printf(" %s", inet_ntoa(t->laddr));
else
for (i = 0; i < t->spool_cnt; i++) {
s = (struct nat44_cfg_spool *)&buf[off];
if (i)
printf(",");
else
printf(" ");
printf("%s", inet_ntoa(s->addr));
off += sizeof(struct nat44_cfg_spool);
}
printf(" %s", inet_ntoa(t->paddr));
break;
case REDIR_PORT:
p = getprotobynumber(t->proto);
printf(" redirect_port %s ", p->p_name);
if (!t->spool_cnt) {
printf("%s:%u", inet_ntoa(t->laddr), t->lport);
if (t->pport_cnt > 1)
printf("-%u", t->lport +
t->pport_cnt - 1);
} else
for (i=0; i < t->spool_cnt; i++) {
s = (struct nat44_cfg_spool *)&buf[off];
if (i)
printf(",");
printf("%s:%u", inet_ntoa(s->addr),
s->port);
off += sizeof(struct nat44_cfg_spool);
}
printf(" ");
if (t->paddr.s_addr)
printf("%s:", inet_ntoa(t->paddr));
printf("%u", t->pport);
if (!t->spool_cnt && t->pport_cnt > 1)
printf("-%u", t->pport + t->pport_cnt - 1);
if (t->raddr.s_addr) {
printf(" %s", inet_ntoa(t->raddr));
if (t->rport) {
printf(":%u", t->rport);
if (!t->spool_cnt && t->rport_cnt > 1)
printf("-%u", t->rport +
t->rport_cnt - 1);
}
}
break;
case REDIR_PROTO:
p = getprotobynumber(t->proto);
printf(" redirect_proto %s %s", p->p_name,
inet_ntoa(t->laddr));
if (t->paddr.s_addr != 0) {
printf(" %s", inet_ntoa(t->paddr));
if (t->raddr.s_addr)
printf(" %s", inet_ntoa(t->raddr));
}
break;
default:
errx(EX_DATAERR, "unknown redir mode");
break;
}
}
printf("\n");
}
static int
nat_port_alias_parse(char *str, u_short *lpout, u_short *hpout) {
long lp, hp;
char *ptr;
/* Lower port parsing */
lp = (long) strtol(str, &ptr, 10);
if (lp < 1024 || lp > 65535)
return 0;
if (!ptr || *ptr != '-')
return 0;
/* Upper port parsing */
hp = (long) strtol(ptr, &ptr, 10);
if (hp < 1024 || hp > 65535)
return 0;
if (ptr)
return 0;
*lpout = (u_short) lp;
*hpout = (u_short) hp;
return 1;
}
void
ipfw_config_nat(int ac, char **av)
{
ipfw_obj_header *oh;
struct nat44_cfg_nat *n; /* Nat instance configuration. */
int i, off, tok, ac1;
u_short lp, hp;
char *id, *buf, **av1, *end;
size_t len;
av++;
ac--;
/* Nat id. */
if (ac == 0)
errx(EX_DATAERR, "missing nat id");
id = *av;
i = (int)strtol(id, &end, 0);
if (i <= 0 || *end != '\0')
errx(EX_DATAERR, "illegal nat id: %s", id);
av++;
ac--;
if (ac == 0)
errx(EX_DATAERR, "missing option");
len = sizeof(*oh) + sizeof(*n);
ac1 = ac;
av1 = av;
while (ac1 > 0) {
tok = match_token(nat_params, *av1);
ac1--;
av1++;
switch (tok) {
case TOK_IP:
case TOK_IF:
case TOK_PORT_ALIAS:
ac1--;
av1++;
break;
case TOK_ALOG:
case TOK_DENY_INC:
case TOK_SAME_PORTS:
case TOK_SKIP_GLOBAL:
case TOK_UNREG_ONLY:
case TOK_UNREG_CGN:
case TOK_RESET_ADDR:
case TOK_ALIAS_REV:
case TOK_PROXY_ONLY:
break;
case TOK_REDIR_ADDR:
if (ac1 < 2)
errx(EX_DATAERR, "redirect_addr: "
"not enough arguments");
len += estimate_redir_addr(&ac1, &av1);
av1 += 2;
ac1 -= 2;
break;
case TOK_REDIR_PORT:
if (ac1 < 3)
errx(EX_DATAERR, "redirect_port: "
"not enough arguments");
av1++;
ac1--;
len += estimate_redir_port(&ac1, &av1);
av1 += 2;
ac1 -= 2;
/* Skip optional remoteIP/port */
if (ac1 != 0 && isdigit(**av1)) {
av1++;
ac1--;
}
break;
case TOK_REDIR_PROTO:
if (ac1 < 2)
errx(EX_DATAERR, "redirect_proto: "
"not enough arguments");
len += sizeof(struct nat44_cfg_redir);
av1 += 2;
ac1 -= 2;
/* Skip optional remoteIP/port */
if (ac1 != 0 && isdigit(**av1)) {
av1++;
ac1--;
}
if (ac1 != 0 && isdigit(**av1)) {
av1++;
ac1--;
}
break;
default:
errx(EX_DATAERR, "unrecognised option ``%s''", av1[-1]);
}
}
if ((buf = malloc(len)) == NULL)
errx(EX_OSERR, "malloc failed");
/* Offset in buf: save space for header at the beginning. */
off = sizeof(*oh) + sizeof(*n);
memset(buf, 0, len);
oh = (ipfw_obj_header *)buf;
n = (struct nat44_cfg_nat *)(oh + 1);
oh->ntlv.head.length = sizeof(oh->ntlv);
snprintf(oh->ntlv.name, sizeof(oh->ntlv.name), "%d", i);
snprintf(n->name, sizeof(n->name), "%d", i);
while (ac > 0) {
tok = match_token(nat_params, *av);
ac--;
av++;
switch (tok) {
case TOK_IP:
if (ac == 0)
errx(EX_DATAERR, "missing option");
if (!inet_aton(av[0], &(n->ip)))
errx(EX_DATAERR, "bad ip address ``%s''",
av[0]);
ac--;
av++;
break;
case TOK_IF:
if (ac == 0)
errx(EX_DATAERR, "missing option");
set_addr_dynamic(av[0], n);
ac--;
av++;
break;
case TOK_ALOG:
n->mode |= PKT_ALIAS_LOG;
break;
case TOK_DENY_INC:
n->mode |= PKT_ALIAS_DENY_INCOMING;
break;
case TOK_SAME_PORTS:
n->mode |= PKT_ALIAS_SAME_PORTS;
break;
case TOK_UNREG_ONLY:
n->mode |= PKT_ALIAS_UNREGISTERED_ONLY;
break;
case TOK_UNREG_CGN:
n->mode |= PKT_ALIAS_UNREGISTERED_CGN;
break;
case TOK_SKIP_GLOBAL:
n->mode |= PKT_ALIAS_SKIP_GLOBAL;
break;
case TOK_RESET_ADDR:
n->mode |= PKT_ALIAS_RESET_ON_ADDR_CHANGE;
break;
case TOK_ALIAS_REV:
n->mode |= PKT_ALIAS_REVERSE;
break;
case TOK_PROXY_ONLY:
n->mode |= PKT_ALIAS_PROXY_ONLY;
break;
/*
* All the setup_redir_* functions work directly in
* the final buffer, see above for details.
*/
case TOK_REDIR_ADDR:
case TOK_REDIR_PORT:
case TOK_REDIR_PROTO:
switch (tok) {
case TOK_REDIR_ADDR:
i = setup_redir_addr(&buf[off], &ac, &av);
break;
case TOK_REDIR_PORT:
i = setup_redir_port(&buf[off], &ac, &av);
break;
case TOK_REDIR_PROTO:
i = setup_redir_proto(&buf[off], &ac, &av);
break;
}
n->redir_cnt++;
off += i;
break;
case TOK_PORT_ALIAS:
if (ac == 0)
errx(EX_DATAERR, "missing option");
if (!nat_port_alias_parse(av[0], &lp, &hp))
errx(EX_DATAERR,
"You need a range of port(s) from 1024 <= x < 65536");
if (lp >= hp)
errx(EX_DATAERR,
"Upper port has to be greater than lower port");
n->alias_port_lo = lp;
n->alias_port_hi = hp;
ac--;
av++;
break;
}
}
if (n->mode & PKT_ALIAS_SAME_PORTS && n->alias_port_lo)
errx(EX_DATAERR, "same_ports and port_range cannot both be selected");
i = do_set3(IP_FW_NAT44_XCONFIG, &oh->opheader, len);
if (i != 0)
err(1, "setsockopt(%s)", "IP_FW_NAT44_XCONFIG");
if (!g_co.do_quiet) {
/* After every modification, we show the resultant rule. */
int _ac = 3;
const char *_av[] = {"show", "config", id};
ipfw_show_nat(_ac, (char **)(void *)_av);
}
}
static void
nat_fill_ntlv(ipfw_obj_ntlv *ntlv, int i)
{
ntlv->head.type = IPFW_TLV_EACTION_NAME(1); /* it doesn't matter */
ntlv->head.length = sizeof(ipfw_obj_ntlv);
ntlv->idx = 1;
ntlv->set = 0; /* not yet */
snprintf(ntlv->name, sizeof(ntlv->name), "%d", i);
}
int
ipfw_delete_nat(int i)
{
ipfw_obj_header oh;
int ret;
memset(&oh, 0, sizeof(oh));
nat_fill_ntlv(&oh.ntlv, i);