/* Code to take an iptables-style command line and do it. */
/*
* Author: Paul.Russell@rustcorp.com.au and mneuling@radlogic.com.au
*
* (C) 2000-2002 by the netfilter coreteam <coreteam@netfilter.org>:
* Paul 'Rusty' Russell <rusty@rustcorp.com.au>
* Marc Boucher <marc+nf@mbsi.ca>
* James Morris <jmorris@intercode.com.au>
* Harald Welte <laforge@gnumonks.org>
* Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <getopt.h>
#include <string.h>
#include <netdb.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <dlfcn.h>
#include <ctype.h>
#include <stdarg.h>
#include <limits.h>
#include <unistd.h>
#include <iptables.h>
#include <fcntl.h>
#include <sys/wait.h>
#include <sys/utsname.h>
#include <netinet/in.h>
#ifndef TRUE
#define TRUE 1
#endif
#ifndef FALSE
#define FALSE 0
#endif
#ifndef PROC_SYS_MODPROBE
#define PROC_SYS_MODPROBE "/proc/sys/kernel/modprobe"
#endif
#define FMT_NUMERIC 0x0001
#define FMT_NOCOUNTS 0x0002
#define FMT_KILOMEGAGIGA 0x0004
#define FMT_OPTIONS 0x0008
#define FMT_NOTABLE 0x0010
#define FMT_NOTARGET 0x0020
#define FMT_VIA 0x0040
#define FMT_NONEWLINE 0x0080
#define FMT_LINENUMBERS 0x0100
#define FMT_PRINT_RULE (FMT_NOCOUNTS | FMT_OPTIONS | FMT_VIA \
| FMT_NUMERIC | FMT_NOTABLE)
#define FMT(tab,notab) ((format) & FMT_NOTABLE ? (notab) : (tab))
#define CMD_NONE 0x0000U
#define CMD_INSERT 0x0001U
#define CMD_DELETE 0x0002U
#define CMD_DELETE_NUM 0x0004U
#define CMD_REPLACE 0x0008U
#define CMD_APPEND 0x0010U
#define CMD_LIST 0x0020U
#define CMD_FLUSH 0x0040U
#define CMD_ZERO 0x0080U
#define CMD_NEW_CHAIN 0x0100U
#define CMD_DELETE_CHAIN 0x0200U
#define CMD_SET_POLICY 0x0400U
#define CMD_RENAME_CHAIN 0x0800U
#define NUMBER_OF_CMD 13
static const char cmdflags[] = { 'I', 'D', 'D', 'R', 'A', 'L', 'F', 'Z',
'N', 'X', 'P', 'E' };
#define OPTION_OFFSET 256
#define OPT_NONE 0x00000U
#define OPT_NUMERIC 0x00001U
#define OPT_SOURCE 0x00002U
#define OPT_DESTINATION 0x00004U
#define OPT_PROTOCOL 0x00008U
#define OPT_JUMP 0x00010U
#define OPT_VERBOSE 0x00020U
#define OPT_EXPANDED 0x00040U
#define OPT_VIANAMEIN 0x00080U
#define OPT_VIANAMEOUT 0x00100U
#define OPT_FRAGMENT 0x00200U
#define OPT_LINENUMBERS 0x00400U
#define OPT_COUNTERS 0x00800U
#define NUMBER_OF_OPT 12
static const char optflags[NUMBER_OF_OPT]
= { 'n', 's', 'd', 'p', 'j', 'v', 'x', 'i', 'o', 'f', '0', 'c'};
static struct option original_opts[] = {
{ "append", 1, 0, 'A' },
{ "delete", 1, 0, 'D' },
{ "insert", 1, 0, 'I' },
{ "replace", 1, 0, 'R' },
{ "list", 2, 0, 'L' },
{ "flush", 2, 0, 'F' },
{ "zero", 2, 0, 'Z' },
{ "new-chain", 1, 0, 'N' },
{ "delete-chain", 2, 0, 'X' },
{ "rename-chain", 1, 0, 'E' },
{ "policy", 1, 0, 'P' },
{ "source", 1, 0, 's' },
{ "destination", 1, 0, 'd' },
{ "src", 1, 0, 's' }, /* synonym */
{ "dst", 1, 0, 'd' }, /* synonym */
{ "protocol", 1, 0, 'p' },
{ "in-interface", 1, 0, 'i' },
{ "jump", 1, 0, 'j' },
{ "table", 1, 0, 't' },
{ "match", 1, 0, 'm' },
{ "numeric", 0, 0, 'n' },
{ "out-interface", 1, 0, 'o' },
{ "verbose", 0, 0, 'v' },
{ "exact", 0, 0, 'x' },
{ "fragments", 0, 0, 'f' },
{ "version", 0, 0, 'V' },
{ "help", 2, 0, 'h' },
{ "line-numbers", 0, 0, '0' },
{ "modprobe", 1, 0, 'M' },
{ "set-counters", 1, 0, 'c' },
{ "goto", 1, 0, 'g' },
{ 0 }
};
/* we need this for iptables-restore. iptables-restore.c sets line to the
* current line of the input file, in order to give a more precise error
* message. iptables itself doesn't need this, so it is initialized to the
* magic number of -1 */
int line = -1;
static struct option *opts = original_opts;
static unsigned int global_option_offset = 0;
/* Table of legal combinations of commands and options. If any of the
* given commands make an option legal, that option is legal (applies to
* CMD_LIST and CMD_ZERO only).
* Key:
* + compulsory
* x illegal
* optional
*/
static char commands_v_options[NUMBER_OF_CMD][NUMBER_OF_OPT] =
/* Well, it's better than "Re: Linux vs FreeBSD" */
{
/* -n -s -d -p -j -v -x -i -o -f --line -c */
/*INSERT*/ {'x',' ',' ',' ',' ',' ','x',' ',' ',' ','x',' '},
/*DELETE*/ {'x',' ',' ',' ',' ',' ','x',' ',' ',' ','x','x'},
/*DELETE_NUM*/{'x','x','x','x','x',' ','x','x','x','x','x','x'},
/*REPLACE*/ {'x',' ',' ',' ',' ',' ','x',' ',' ',' ','x',' '},
/*APPEND*/ {'x',' ',' ',' ',' ',' ','x',' ',' ',' ','x',' '},
/*LIST*/ {' ','x','x','x','x',' ',' ','x','x','x',' ','x'},
/*FLUSH*/ {'x','x','x','x','x',' ','x','x','x','x','x','x'},
/*ZERO*/ {'x','x','x','x','x',' ','x','x','x','x','x','x'},
/*NEW_CHAIN*/ {'x','x','x','x','x',' ','x','x','x','x','x','x'},
/*DEL_CHAIN*/ {'x','x','x','x','x',' ','x','x','x','x','x','x'},
/*SET_POLICY*/{'x','x','x','x','x',' ','x','x','x','x','x','x'},
/*RENAME*/ {'x','x','x','x','x',' ','x','x','x','x','x','x'}
};
static int inverse_for_options[NUMBER_OF_OPT] =
{
/* -n */ 0,
/* -s */ IPT_INV_SRCIP,
/* -d */ IPT_INV_DSTIP,
/* -p */ IPT_INV_PROTO,
/* -j */ 0,
/* -v */ 0,
/* -x */ 0,
/* -i */ IPT_INV_VIA_IN,
/* -o */ IPT_INV_VIA_OUT,
/* -f */ IPT_INV_FRAG,
/*--line*/ 0,
/* -c */ 0,
};
const char *program_version;
const char *program_name;
char *lib_dir;
int kernel_version;
/* the path to command to load kernel module */
const char *modprobe = NULL;
/* Keeping track of external matches and targets: linked lists. */
struct iptables_match *iptables_matches = NULL;
struct iptables_target *iptables_targets = NULL;
/* Extra debugging from libiptc */
extern void dump_entries(const iptc_handle_t handle);
/* A few hardcoded protocols for 'all' and in case the user has no
/etc/protocols */
struct pprot {
char *name;
u_int8_t num;
};
/* Primitive headers... */
/* defined in netinet/in.h */
#if 0
#ifndef IPPROTO_ESP
#define IPPROTO_ESP 50
#endif
#ifndef IPPROTO_AH
#define IPPROTO_AH 51
#endif
#endif
static const struct pprot chain_protos[] = {
{ "tcp", IPPROTO_TCP },
{ "udp", IPPROTO_UDP },
{ "udplite", IPPROTO_UDPLITE },
{ "icmp", IPPROTO_ICMP },
{ "esp", IPPROTO_ESP },
{ "ah", IPPROTO_AH },
{ "sctp", IPPROTO_SCTP },
};
static char *
proto_to_name(u_int8_t proto, int nolookup)
{
unsigned int i;
if (proto && !nolookup) {
struct protoent *pent = getprotobynumber(proto);
if (pent)
return pent->p_name;
}
for (i = 0; i < sizeof(chain_protos)/sizeof(struct pprot); i++)
if (chain_protos[i].num == proto)
return chain_protos[i].name;
return NULL;
}
int
service_to_port(const char *name, const char *proto)
{
struct servent *service;
if ((service = getservbyname(name, proto)) != NULL)
return ntohs((unsigned short) service->s_port);
return -1;
}
u_int16_t
parse_port(const char *port, const char *proto)
{
unsigned int portnum;
if ((string_to_number(port, 0, 65535, &portnum)) != -1 ||
(portnum = service_to_port(port, proto)) != -1)
return (u_int16_t)portnum;
exit_error(PARAMETER_PROBLEM,
"invalid port/service `%s' specified", port);
}
enum {
IPT_DOTTED_ADDR = 0,
IPT_DOTTED_MASK
};
static struct in_addr *
__dotted_to_addr(const char *dotted, int type)
{
static struct in_addr addr;
unsigned char *addrp;
char *p, *q;
unsigned int onebyte;
int i;
char buf[20];
/* copy dotted string, because we need to modify it */
strncpy(buf, dotted, sizeof(buf) - 1);
buf[sizeof(buf) - 1] = '\0';
addrp = (unsigned char *) &(addr.s_addr);
p = buf;
for (i = 0; i < 3; i++) {
if ((q = strchr(p, '.')) == NULL) {
if (type == IPT_DOTTED_ADDR) {
/* autocomplete, this is a network address */
if (string_to_number(p, 0, 255, &onebyte) == -1)
return (struct in_addr *) NULL;
addrp[i] = (unsigned char) onebyte;
while (i < 3)
addrp[++i] = 0;
return &addr;
} else
return (struct in_addr *) NULL;
}
*q = '\0';
if (string_to_number(p, 0, 255, &onebyte) == -1)
return (struct in_addr *) NULL;
addrp[i] = (unsigned char) onebyte;
p = q + 1;
}
/* we've checked 3 bytes, now we check the last one */
if (string_to_number(p, 0, 255, &onebyte) == -1)
return (struct in_addr *) NULL;
addrp[3] = (unsigned char) onebyte;
return &addr;
}
struct in_addr *
dotted_to_addr(const char *dotted)
{
return __dotted_to_addr(dotted, IPT_DOTTED_ADDR);
}
struct in_addr *
dotted_to_mask(const char *dotted)
{
return __dotted_to_addr(dotted, IPT_DOTTED_MASK);
}
static struct in_addr *
network_to_addr(const char *name)
{
struct netent *net;
static struct in_addr addr;
if ((net = getnetbyname(name)) != NULL) {
if (net->n_addrtype != AF_INET)
return (struct in_addr *) NULL;
addr.s_addr = htonl((unsigned long) net->n_net);
return &addr;
}
return (struct in_addr *) NULL;
}
static void
inaddrcpy(struct in_addr *dst, struct in_addr *src)
{
/* memcpy(dst, src, sizeof(struct in_addr)); */
dst->s_addr = src->s_addr;
}
static void free_opts(int reset_offset)
{
if (opts != original_opts) {
free(opts);
opts = original_opts;
if (reset_offset)
global_option_offset = 0;
}
}
void
exit_error(enum exittype status, char *msg, ...)
{
va_list args;
va_start(args, msg);
fprintf(stderr, "%s v%s: ", program_name, program_version);
vfprintf(stderr, msg, args);
va_end(args);
fprintf(stderr, "\n");
if (status == PARAMETER_PROBLEM)
exit_tryhelp(status);
if (status == VERSION_PROBLEM)
fprintf(stderr,
"Perhaps iptables or your kernel needs to be upgraded.\n");
/* On error paths, make sure that we don't leak memory */
free_opts(1);
exit(status);
}
void
exit_tryhelp(int status)
{
if (line != -1)
fprintf(stderr, "Error occurred at line: %d\n", line);
fprintf(stderr, "Try `%s -h' or '%s --help' for more information.\n",
program_name, program_name );
free_opts(1);
exit(status);
}
void
exit_printhelp(struct iptables_rule_match *matches)
{
struct iptables_rule_match *matchp = NULL;
struct iptables_target *t = NULL;
printf("%s v%s\n\n"
"Usage: %s -[AD] chain rule-specification [options]\n"
" %s -[RI] chain rulenum rule-specification [options]\n"
" %s -D chain rulenum [options]\n"
" %s -[LFZ] [chain] [options]\n"
" %s -[NX] chain\n"
" %s -E old-chain-name new-chain-name\n"
" %s -P chain target [options]\n"
" %s -h (print this help information)\n\n",
program_name, program_version, program_name, program_name,
program_name, program_name, program_name, program_name,
program_name, program_name);
printf(
"Commands:\n"
"Either long or short options are allowed.\n"
" --append -A chain Append to chain\n"
" --delete -D chain Delete matching rule from chain\n"
" --delete -D chain rulenum\n"
" Delete rule rulenum (1 = first) from chain\n"
" --insert -I chain [rulenum]\n"
" Insert in chain as rulenum (default 1=first)\n"
" --replace -R chain rulenum\n"
" Replace rule rulenum (1 = first) in chain\n"
" --list -L [chain] List the rules in a chain or all chains\n"
" --flush -F [chain] Delete all rules in chain or all chains\n"
" --zero -Z [chain] Zero counters in chain or all chains\n"
" --new -N chain Create a new user-defined chain\n"
" --delete-chain\n"
" -X [chain] Delete a user-defined chain\n"
" --policy -P chain target\n"
" Change policy on chain to target\n"
" --rename-chain\n"
" -E old-chain new-chain\n"
" Change chain name, (moving any references)\n"
"Options:\n"
" --proto -p [!] proto protocol: by number or name, eg. `tcp'\n"
" --source -s [!] address[/mask]\n"
" source specification\n"
" --destination -d [!] address[/mask]\n"
" destination specification\n"
" --in-interface -i [!] input name[+]\n"
" network interface name ([+] for wildcard)\n"
" --jump -j target\n"
" target for rule (may load target extension)\n"
#ifdef IPT_F_GOTO
" --goto -g chain\n"
" jump to chain with no return\n"
#endif
" --match -m match\n"
" extended match (may load extension)\n"
" --numeric -n numeric output of addresses and ports\n"
" --out-interface -o [!] output name[+]\n"
" network interface name ([+] for wildcard)\n"
" --table -t table table to manipulate (default: `filter')\n"
" --verbose -v verbose mode\n"
" --line-numbers print line numbers when listing\n"
" --exact -x expand numbers (display exact values)\n"
"[!] --fragment -f match second or further fragments only\n"
" --modprobe=<command> try to insert modules using this command\n"
" --set-counters PKTS BYTES set the counter during insert/append\n"
"[!] --version -V print package version.\n");
/* Print out any special helps. A user might like to be able
to add a --help to the commandline, and see expected
results. So we call help for all specified matches & targets */
for (t = iptables_targets; t ;t = t->next) {
if (t->used) {
printf("\n");
t->help();
}
}
for (matchp = matches; matchp; matchp = matchp->next) {
printf("\n");
matchp->match->help();
}
exit(0);
}
static void
generic_opt_check(int command, int options)
{
int i, j, legal = 0;
/* Check that commands are valid with options. Complicated by the
* fact that if an option is legal with *any* command given, it is
* legal overall (ie. -z and -l).
*/
for (i = 0; i < NUMBER_OF_OPT; i++) {
legal = 0; /* -1 => illegal, 1 => legal, 0 => undecided. */
for (j = 0; j < NUMBER_OF_CMD; j++) {
if (!(command & (1<<j)))
continue;
if (!(options & (1<<i))) {
if (commands_v_options[j][i] == '+')
exit_error(PARAMETER_PROBLEM,
"You need to supply the `-%c' "
"option for this command\n",
optflags[i]);
} else {
if (commands_v_options[j][i] != 'x')
legal = 1;
else if (legal == 0)
legal = -1;
}
}
if (legal == -1)
exit_error(PARAMETER_PROBLEM,
"Illegal option `-%c' with this command\n",
optflags[i]);
}
}
static char
opt2char(int option)
{
const char *ptr;
for (ptr = optflags; option > 1; option >>= 1, ptr++);
return *ptr;
}
static char
cmd2char(int option)
{
const char *ptr;
for (ptr = cmdflags; option > 1; option >>= 1, ptr++);
return *ptr;
}
static void
add_command(unsigned int *cmd, const int newcmd, const int othercmds,
int invert)
{
if (invert)
exit_error(PARAMETER_PROBLEM, "unexpected ! flag");
if (*cmd & (~othercmds))
exit_error(PARAMETER_PROBLEM, "Can't use -%c with -%c\n",
cmd2char(newcmd), cmd2char(*cmd & (~othercmds)));
*cmd |= newcmd;
}
int
check_inverse(const char option[], int *invert, int *optind, int argc)
{
if (option && strcmp(option, "!") == 0) {
if (*invert)
exit_error(PARAMETER_PROBLEM,
"Multiple `!' flags not allowed");
*invert = TRUE;
if (optind) {
*optind = *optind+1;
if (argc && *optind > argc)
exit_error(PARAMETER_PROBLEM,
"no argument following `!'");
}
return TRUE;
}
return FALSE;
}
static void *
fw_calloc(size_t count, size_t size)
{
void *p;
if ((p = calloc(count, size)) == NULL) {
perror("iptables: calloc failed");
exit(1);
}
return p;
}
static void *
fw_malloc(size_t size)
{
void *p;
if ((p = malloc(size)) == NULL) {
perror("iptables: malloc failed");
exit(1);
}
return p;
}
static struct in_addr *
host_to_addr(const char *name, unsigned int *naddr)
{
struct hostent *host;
struct in_addr *addr;
unsigned int i;
*naddr = 0;
if ((host = gethostbyname(name)) != NULL) {
if (host->h_addrtype != AF_INET ||
host->h_length != sizeof(struct in_addr))
return (struct in_addr *) NULL;
while (host->h_addr_list[*naddr] != (char *) NULL)
(*naddr)++;
addr = fw_calloc(*naddr, sizeof(struct in_addr) * *naddr);
for (i = 0; i < *naddr; i++)
inaddrcpy(&(addr[i]),
(struct in_addr *) host->h_addr_list[i]);
return addr;
}
return (struct in_addr *) NULL;
}
static char *
addr_to_host(const struct in_addr *addr)
{
struct hostent *host;
if ((host = gethostbyaddr((char *) addr,
sizeof(struct in_addr), AF_INET)) != NULL)
return (char *) host->h_name;
return (char *) NULL;
}
/*
* All functions starting with "parse" should succeed, otherwise
* the program fails.
* Most routines return pointers to static data that may change
* between calls to the same or other routines with a few exceptions:
* "host_to_addr", "parse_hostnetwork", and "parse_hostnetworkmask"
* return global static data.
*/
static struct in_addr *
parse_hostnetwork(const char *name, unsigned int *naddrs)
{
struct in_addr *addrp, *addrptmp;
if ((addrptmp = dotted_to_addr(name)) != NULL ||
(addrptmp = network_to_addr(name)) != NULL) {
addrp = fw_malloc(sizeof(struct in_addr));
inaddrcpy(addrp, addrptmp);
*naddrs = 1;
return addrp;
}
if ((addrp = host_to_addr(name, naddrs)) != NULL)
return addrp;
exit_error(PARAMETER_PROBLEM, "host/network `%s' not found", name);
}
static struct in_addr *
parse_mask(char *mask)
{
static struct in_addr maskaddr;
struct in_addr *addrp;
unsigned int bits;
if (mask == NULL) {
/* no mask at all defaults to 32 bits */
maskaddr.s_addr = 0xFFFFFFFF;
return &maskaddr;
}
if ((addrp = dotted_to_mask(mask)) != NULL)
/* dotted_to_addr already returns a network byte order addr */
return addrp;
if (string_to_number(mask, 0, 32, &bits) == -1)
exit_error(PARAMETER_PROBLEM,
"invalid mask `%s' specified", mask);
if (bits != 0) {
maskaddr.s_addr = htonl(0xFFFFFFFF << (32 - bits));
return &maskaddr;
}
maskaddr.s_addr = 0L;
return &maskaddr;
}
void
parse_hostnetworkmask(const char *name, struct in_addr **addrpp,
struct in_addr *maskp, unsigned int *naddrs)
{
struct in_addr *addrp;
char buf[256];
char *p;
int i, j, k, n;
strncpy(buf, name, sizeof(buf) - 1);
buf[sizeof(buf) - 1] = '\0';
if ((p = strrchr(buf, '/')) != NULL) {
*p = '\0';
addrp = parse_mask(p + 1);
} else
addrp = parse_mask(NULL);
inaddrcpy(maskp, addrp);
/* if a null mask is given, the name is ignored, like in "any/0" */
if (maskp->s_addr == 0L)
strcpy(buf, "0.0.0.0");
addrp = *addrpp = parse_hostnetwork(buf, naddrs);
n = *naddrs;
for (i = 0, j = 0; i < n; i++) {
addrp[j++].s_addr &= maskp->s_addr;
for (k = 0; k < j - 1; k++) {
if (addrp[k].s_addr == addrp[j - 1].s_addr) {
(*naddrs)--;
j--;
break;
}
}
}
}
struct iptables_match *
find_match(const char *name, enum ipt_tryload tryload, struct iptables_rule_match **matches)
{
struct iptables_match *ptr;
for (ptr = iptables_matches; ptr; ptr = ptr->next) {
if (strcmp(name, ptr->name) == 0) {
struct iptables_match *clone;
/* First match of this type: */
if (ptr->m == NULL)
break;
/* Second and subsequent clones */
clone = fw_malloc(sizeof(struct iptables_match));
memcpy(clone, ptr, sizeof(struct iptables_match));
clone->mflags = 0;
/* This is a clone: */
clone->next = clone;
ptr = clone;
break;
}
}
#ifndef NO_SHARED_LIBS
if (!ptr && tryload != DONT_LOAD && tryload != DURING_LOAD) {
char path[strlen(lib_dir) + sizeof("/libipt_.so")
+ strlen(name)];
sprintf(path, "%s/libipt_%s.so", lib_dir, name);
if (dlopen(path, RTLD_NOW)) {
/* Found library. If it didn't register itself,
maybe they specified target as match. */
ptr = find_match(name, DONT_LOAD, NULL);
if (!ptr)
exit_error(PARAMETER_PROBLEM,
"Couldn't load match `%s'\n",
name);
} else if (tryload == LOAD_MUST_SUCCEED)
exit_error(PARAMETER_PROBLEM,
"Couldn't load match `%s':%s\n",
name, dlerror());
}
#else
if (ptr && !ptr->loaded) {
if (tryload != DONT_LOAD)
ptr->loaded = 1;
else
ptr = NULL;
}
if(!ptr && (tryload == LOAD_MUST_SUCCEED)) {
exit_error(PARAMETER_PROBLEM,
"Couldn't find match `%s'\n", name);
}
#endif
if (ptr && matches) {
struct iptables_rule_match **i;
struct iptables_rule_match *newentry;
newentry = fw_malloc(sizeof(struct iptables_rule_match));
for (i = matches; *i; i = &(*i)->next) {
if (strcmp(name, (*i)->match->name) == 0)
(*i)->completed = 1;
}
newentry->match = ptr;
newentry->completed = 0;
newentry->next = NULL;
*i = newentry;
}
return ptr;
}
/* Christophe Burki wants `-p 6' to imply `-m tcp'. */
static struct iptables_match *
find_proto(const char *pname, enum ipt_tryload tryload, int nolookup, struct iptables_rule_match **matches)
{
unsigned int proto;
if (string_to_number(pname, 0, 255, &proto) != -1) {
char *protoname = proto_to_name(proto, nolookup);
if (protoname)
return find_match(protoname, tryload, matches);
} else
return find_match(pname, tryload, matches);
return NULL;
}
u_int16_t
parse_protocol(const char *s)
{
unsigned int proto;
if (string_to_number(s, 0, 255, &proto) == -1) {
struct protoent *pent;
/* first deal with the special case of 'all' to prevent
* people from being able to redefine 'all' in nsswitch
* and/or provoke expensive [not working] ldap/nis/...
* lookups */
if (!strcmp(s, "all"))
return 0;
if ((pent = getprotobyname(s)))
proto = pent->p_proto;
else {
unsigned int i;
for (i = 0;
i < sizeof(chain_protos)/sizeof(struct pprot);
i++) {
if (strcmp(s, chain_protos[i].name) == 0) {
proto = chain_protos[i].num;
break;
}
}
if (i == sizeof(chain_protos)/sizeof(struct pprot))
exit_error(PARAMETER_PROBLEM,
"unknown protocol `%s' specified",
s);
}
}
return (u_int16_t)proto;
}
void parse_interface(const char *arg, char *vianame, unsigned char *mask)
{
int vialen = strlen(arg);
unsigned int i;
memset(mask, 0, IFNAMSIZ);
memset(vianame, 0, IFNAMSIZ);
if (vialen + 1 > IFNAMSIZ)
exit_error(PARAMETER_PROBLEM,
"interface name `%s' must be shorter than IFNAMSIZ"
" (%i)", arg, IFNAMSIZ-1);
strcpy(vianame, arg);
if ((vialen == 0) || (vialen == 1 && vianame[0] == '+'))
memset(mask, 0, IFNAMSIZ);
else if (vianame[vialen - 1] == '+') {
memset(mask, 0xFF, vialen - 1);
memset(mask + vialen - 1, 0, IFNAMSIZ - vialen + 1);
/* Don't remove `+' here! -HW */
} else {
/* Include nul-terminator in match */
memset(mask, 0xFF, vialen + 1);
memset(mask + vialen + 1, 0, IFNAMSIZ - vialen - 1);
for (i = 0; vianame[i]; i++) {
if (vianame[i] == ':' ||
vianame[i] == '!' ||
vianame[i] == '*') {
printf("Warning: weird character in interface"
" `%s' (No aliases, :, ! or *).\n",
vianame);
break;
}
}
}
}
/* Can't be zero. */
static int
parse_rulenumber(const char *rule)
{
unsigned int rulenum;
if (string_to_number(rule, 1, INT_MAX, &rulenum) == -1)
exit_error(PARAMETER_PROBLEM,
"Invalid rule number `%s'", rule);
return rulenum;
}
static const char *
parse_target(const char *targetname)
{
const char *ptr;
if (strlen(targetname) < 1)
exit_error(PARAMETER_PROBLEM,
"Invalid target name (too short)");
if (strlen(targetname)+1 > sizeof(ipt_chainlabel))
exit_error(PARAMETER_PROBLEM,
"Invalid target name `%s' (%u chars max)",
targetname, (unsigned int)sizeof(ipt_chainlabel)-1);
for (ptr = targetname; *ptr; ptr++)
if (isspace(*ptr))
exit_error(PARAMETER_PROBLEM,
"Invalid target name `%s'", targetname);
return targetname;
}
static char *
addr_to_network(const struct in_addr *addr)
{
struct netent *net;
if ((net = getnetbyaddr((long) ntohl(addr->s_addr), AF_INET)) != NULL)
return (char *) net->n_name;
return (char *) NULL;
}
char *
addr_to_dotted(const struct in_addr *addrp)
{
static char buf[20];
const unsigned char *bytep;
bytep = (const unsigned char *) &(addrp->s_addr);
sprintf(buf, "%d.%d.%d.%d", bytep[0], bytep[1], bytep[2], bytep[3]);
return buf;
}
char *
addr_to_anyname(const struct in_addr *addr)
{
char *name;
if ((name = addr_to_host(addr)) != NULL ||
(name = addr_to_network(addr)) != NULL)
return name;
return addr_to_dotted(addr);
}
char *
mask_to_dotted(const struct in_addr *mask)
{
int i;
static char buf[20];
u_int32_t maskaddr, bits;
maskaddr = ntohl(mask->s_addr);
if (maskaddr == 0xFFFFFFFFL)
/* we don't want to see "/32" */
return "";
i = 32;
bits = 0xFFFFFFFEL;
while (--i >= 0 && maskaddr != bits)
bits <<= 1;
if (i >= 0)
sprintf(buf, "/%d", i);
else
/* mask was not a decent combination of 1's and 0's */
sprintf(buf, "/%s", addr_to_dotted(mask));
return buf;
}
int
string_to_number_ll(const char *s, unsigned long long min, unsigned long long max,
unsigned long long *ret)
{
unsigned long long number;
char *end;
/* Handle hex, octal, etc. */
errno = 0;
number = strtoull(s, &end, 0);
if (*end == '\0' && end != s) {
/* we parsed a number, let's see if we want this */
if (errno != ERANGE && min <= number && (!max || number <= max)) {
*ret = number;
return 0;
}
}
return -1;
}
int
string_to_number_l(const char *s, unsigned long min, unsigned long max,
unsigned long *ret)
{
int result;
unsigned long long number;
result = string_to_number_ll(s, min, max, &number);
*ret = (unsigned long)number;
return result;
}
int string_to_number(const char *s, unsigned int min, unsigned int max,
unsigned int *ret)
{
int result;
unsigned long number;
result = string_to_number_l(s, min, max, &number);
*ret = (unsigned int)number;
return result;
}
static void
set_option(unsigned int *options, unsigned int option, u_int8_t *invflg,
int invert)
{
if (*options & option)
exit_error(PARAMETER_PROBLEM, "multiple -%c flags not allowed",
opt2char(option));
*options |= option;
if (invert) {
unsigned int i;
for (i = 0; 1 << i != option; i++);
if (!inverse_for_options[i])
exit_error(PARAMETER_PROBLEM,
"cannot have ! before -%c",
opt2char(option));
*invflg |= inverse_for_options[i];
}
}
struct iptables_target *
find_target(const char *name, enum ipt_tryload tryload)
{
struct iptables_target *ptr;
/* Standard target? */
if (strcmp(name, "") == 0
|| strcmp(name, IPTC_LABEL_ACCEPT) == 0
|| strcmp(name, IPTC_LABEL_DROP) == 0
|| strcmp(name, IPTC_LABEL_QUEUE) == 0
|| strcmp(name, IPTC_LABEL_RETURN) == 0)
name = "standard";
for (ptr = iptables_targets; ptr; ptr = ptr->next) {
if (strcmp(name, ptr->name) == 0)
break;
}
#ifndef NO_SHARED_LIBS
if (!ptr && tryload != DONT_LOAD && tryload != DURING_LOAD) {
char path[strlen(lib_dir) + sizeof("/libipt_.so")
+ strlen(name)];
sprintf(path, "%s/libipt_%s.so", lib_dir, name);
if (dlopen(path, RTLD_NOW)) {
/* Found library. If it didn't register itself,
maybe they specified match as a target. */
ptr = find_target(name, DONT_LOAD);
if (!ptr)
exit_error(PARAMETER_PROBLEM,
"Couldn't load target `%s'\n",
name);
} else if (tryload == LOAD_MUST_SUCCEED)
exit_error(PARAMETER_PROBLEM,
"Couldn't load target `%s':%s\n",
name, dlerror());
}
#else
if (ptr && !ptr->loaded) {
if (tryload != DONT_LOAD)
ptr->loaded = 1;
else
ptr = NULL;
}
if(!ptr && (tryload == LOAD_MUST_SUCCEED)) {
exit_error(PARAMETER_PROBLEM,
"Couldn't find target `%s'\n", name);
}
#endif
if (ptr)
ptr->used = 1;
return ptr;
}
static struct option *
merge_options(struct option *oldopts, const struct option *newopts,
unsigned int *option_offset)
{
unsigned int num_old, num_new, i;
struct option *merge;
for (num_old = 0; oldopts[num_old].name; num_old++);
for (num_new = 0; newopts[num_new].name; num_new++);
global_option_offset += OPTION_OFFSET;
*option_offset = global_option_offset;
merge = malloc(sizeof(struct option) * (num_new + num_old + 1));
memcpy(merge, oldopts, num_old * sizeof(struct option));
free_opts(0); /* Release previous options merged if any */
for (i = 0; i < num_new; i++) {
merge[num_old + i] = newopts[i];
merge[num_old + i].val += *option_offset;
}
memset(merge + num_old + num_new, 0, sizeof(struct option));
return merge;
}
static int compatible_revision(const char *name, u_int8_t revision, int opt)
{
struct ipt_get_revision rev;
socklen_t s = sizeof(rev);
int max_rev, sockfd;
sockfd = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
if (sockfd < 0) {
fprintf(stderr, "Could not open socket to kernel: %s\n",
strerror(errno));
exit(1);
}
load_iptables_ko(modprobe);
strcpy(rev.name, name);
rev.revision = revision;
max_rev = getsockopt(sockfd, IPPROTO_IP, opt, &rev, &s);
if (max_rev < 0) {
/* Definitely don't support this? */
if (errno == EPROTONOSUPPORT) {
close(sockfd);
return 0;
} else if (errno == ENOPROTOOPT) {
close(sockfd);
/* Assume only revision 0 support (old kernel) */
return (revision == 0);
} else {
fprintf(stderr, "getsockopt for %s failed strangely: %s\n",
name,
strerror(errno));
/* exit(1); */
}
}
close(sockfd);
return 1;
}
static int compatible_match_revision(const char *name, u_int8_t revision)
{
return compatible_revision(name, revision, IPT_SO_GET_REVISION_MATCH);
}
static int compatible_target_revision(const char *name, u_int8_t revision)
{
return compatible_revision(name, revision, IPT_SO_GET_REVISION_TARGET);
}
void
register_match(struct iptables_match *me)
{
struct iptables_match **i, *old;
if (strcmp(me->version, program_version) != 0) {
fprintf(stderr, "%s: match `%s' v%s (I'm v%s).\n",
program_name, me->name, me->version, program_version);
exit(1);
}
/* Revision field stole a char from name. */
if (strlen(me->name) >= IPT_FUNCTION_MAXNAMELEN-1) {
fprintf(stderr, "%s: target `%s' has invalid name\n",
program_name, me->name);
exit(1);
}
old = find_match(me->name, DURING_LOAD, NULL);
if (old) {
if (old->revision == me->revision) {
fprintf(stderr,
"%s: match `%s' already registered.\n",
program_name, me->name);
exit(1);
}
/* Now we have two (or more) options, check compatibility. */
if (compatible_match_revision(old->name, old->revision)
&& old->revision > me->revision)
return;
/* Replace if compatible. */
if (!compatible_match_revision(me->name, me->revision))
return;
/* Delete old one. */
for (i = &iptables_matches; *i!=old; i = &(*i)->next);
*i = old->next;
}
if (me->size != IPT_ALIGN(me->size)) {
fprintf(stderr, "%s: match `%s' has invalid size %u.\n",
program_name, me->name, (unsigned int)me->size);
exit(1);
}
/* Append to list. */
for (i = &iptables_matches; *i; i = &(*i)->next);
me->next = NULL;
*i = me;
me->m = NULL;
me->mflags = 0;
}
void
register_target(struct iptables_target *me)
{
struct iptables_target *old;
if (strcmp(me->version, program_version) != 0) {
fprintf(stderr, "%s: target `%s' v%s (I'm v%s).\n",
program_name, me->name, me->version, program_version);
exit(1);
}
/* Revision field stole a char from name. */
if (strlen(me->name) >= IPT_FUNCTION_MAXNAMELEN-1) {
fprintf(stderr, "%s: target `%s' has invalid name\n",
program_name, me->name);
exit(1);
}
old = find_target(me->name, DURING_LOAD);
if (old) {
struct iptables_target **i;
if (old->revision == me->revision) {
fprintf(stderr,
"%s: target `%s' already registered.\n",
program_name, me->name);
exit(1);
}
/* Now we have two (or more) options, check compatibility. */
if (compatible_target_revision(old->name, old->revision)
&& old->revision > me->revision)
return;
/* Replace if compatible. */
if (!compatible_target_revision(me->name, me->revision))
return;
/* Delete old one. */
for (i = &iptables_targets; *i!=old; i = &(*i)->next);
*i = old->next;
}
if (me->size != IPT_ALIGN(me->size)) {
fprintf(stderr, "%s: target `%s' has invalid size %u.\n",
program_name, me->name, (unsigned int)me->size);
exit(1);
}
/* Prepend to list. */
me->next = iptables_targets;
iptables_targets = me;
me->t = NULL;
me->tflags = 0;
}
static void
print_num(u_int64_t number, unsigned int format)
{
if (format & FMT_KILOMEGAGIGA) {
if (number > 99999) {
number = (number + 500) / 1000;
if (number > 9999) {
number = (number + 500) / 1000;
if (number > 9999) {
number = (number + 500) / 1000;
if (number > 9999) {
number = (number + 500) / 1000;
printf(FMT("%4lluT ","%lluT "), (unsigned long long)number);
}
else printf(FMT("%4lluG ","%lluG "), (unsigned long long)number);
}
else printf(FMT("%4lluM ","%lluM "), (unsigned long long)number);
} else
printf(FMT("%4lluK ","%lluK "), (unsigned long long)number);
} else
printf(FMT("%5llu ","%llu "), (unsigned long long)number);
} else
printf(FMT("%8llu ","%llu "), (unsigned long long)number);
}
static void
print_header(unsigned int format, const char *chain, iptc_handle_t *handle)
{
struct ipt_counters counters;
const char *pol = iptc_get_policy(chain, &counters, handle);
printf("Chain %s", chain);
if (pol) {
printf(" (policy %s", pol);
if (!(format & FMT_NOCOUNTS)) {
fputc(' ', stdout);
print_num(counters.pcnt, (format|FMT_NOTABLE));
fputs("packets, ", stdout);
print_num(counters.bcnt, (format|FMT_NOTABLE));
fputs("bytes", stdout);
}
printf(")\n");
} else {
unsigned int refs;
if (!iptc_get_references(&refs, chain, handle))
printf(" (ERROR obtaining refs)\n");
else
printf(" (%u references)\n", refs);
}
if (format & FMT_LINENUMBERS)
printf(FMT("%-4s ", "%s "), "num");
if (!(format & FMT_NOCOUNTS)) {
if (format & FMT_KILOMEGAGIGA) {
printf(FMT("%5s ","%s "), "pkts");
printf(FMT("%5s ","%s "), "bytes");
} else {
printf(FMT("%8s ","%s "), "pkts");
printf(FMT("%10s ","%s "), "bytes");
}
}
if (!(format & FMT_NOTARGET))
printf(FMT("%-9s ","%s "), "target");
fputs(" prot ", stdout);
if (format & FMT_OPTIONS)
fputs("opt", stdout);
if (format & FMT_VIA) {
printf(FMT(" %-6s ","%s "), "in");
printf(FMT("%-6s ","%s "), "out");
}
printf(FMT(" %-19s ","%s "), "source");
printf(FMT(" %-19s "," %s "), "destination");
printf("\n");
}
static int
print_match(const struct ipt_entry_match *m,
const struct ipt_ip *ip,
int numeric)
{
struct iptables_match *match = find_match(m->u.user.name, TRY_LOAD, NULL);
if (match) {
if (match->print)
match->print(ip, m, numeric);
else
printf("%s ", match->name);
} else {
if (m->u.user.name[0])
printf("UNKNOWN match `%s' ", m->u.user.name);
}
/* Don't stop iterating. */
return 0;
}
/* e is called `fw' here for hysterical raisins */
static void
print_firewall(const struct ipt_entry *fw,
const char *targname,
unsigned int num,
unsigned int format,
const iptc_handle_t handle)
{
struct iptables_target *target = NULL;
const struct ipt_entry_target *t;
u_int8_t flags;
char buf[BUFSIZ];
if (!iptc_is_chain(targname, handle))
target = find_target(targname, TRY_LOAD);
else
target = find_target(IPT_STANDARD_TARGET, LOAD_MUST_SUCCEED);
t = ipt_get_target((struct ipt_entry *)fw);
flags = fw->ip.flags;
if (format & FMT_LINENUMBERS)
printf(FMT("%-4u ", "%u "), num+1);
if (!(format & FMT_NOCOUNTS)) {
print_num(fw->counters.pcnt, format);
print_num(fw->counters.bcnt, format);
}
if (!(format & FMT_NOTARGET))
printf(FMT("%-9s ", "%s "), targname);
fputc(fw->ip.invflags & IPT_INV_PROTO ? '!' : ' ', stdout);
{
char *pname = proto_to_name(fw->ip.proto, format&FMT_NUMERIC);
if (pname)
printf(FMT("%-5s", "%s "), pname);
else
printf(FMT("%-5hu", "%hu "), fw->ip.proto);
}
if (format & FMT_OPTIONS) {
if (format & FMT_NOTABLE)
fputs("opt ", stdout);
fputc(fw->ip.invflags & IPT_INV_FRAG ? '!' : '-', stdout);
fputc(flags & IPT_F_FRAG ? 'f' : '-', stdout);
fputc(' ', stdout);
}
if (format & FMT_VIA) {
char iface[IFNAMSIZ+2];
if (fw->ip.invflags & IPT_INV_VIA_IN) {
iface[0] = '!';
iface[1] = '\0';
}
else iface[0] = '\0';
if (fw->ip.iniface[0] != '\0') {
strcat(iface, fw->ip.iniface);
}
else if (format & FMT_NUMERIC) strcat(iface, "*");
else strcat(iface, "any");
printf(FMT(" %-6s ","in %s "), iface);
if (fw->ip.invflags & IPT_INV_VIA_OUT) {
iface[0] = '!';
iface[1] = '\0';
}
else iface[0] = '\0';
if (fw->ip.outiface[0] != '\0') {
strcat(iface, fw->ip.outiface);
}
else if (format & FMT_NUMERIC) strcat(iface, "*");
else strcat(iface, "any");
printf(FMT("%-6s ","out %s "), iface);
}
fputc(fw->ip.invflags & IPT_INV_SRCIP ? '!' : ' ', stdout);
if (fw->ip.smsk.s_addr == 0L && !(format & FMT_NUMERIC))
printf(FMT("%-19s ","%s "), "anywhere");
else {
if (format & FMT_NUMERIC)
sprintf(buf, "%s", addr_to_dotted(&(fw->ip.src)));
else
sprintf(buf, "%s", addr_to_anyname(&(fw->ip.src)));
strcat(buf, mask_to_dotted(&(fw->ip.smsk)));
printf(FMT("%-19s ","%s "), buf);
}
fputc(fw->ip.invflags & IPT_INV_DSTIP ? '!' : ' ', stdout);
if (fw->ip.dmsk.s_addr == 0L && !(format & FMT_NUMERIC))
printf(FMT("%-19s ","-> %s"), "anywhere");
else {
if (format & FMT_NUMERIC)
sprintf(buf, "%s", addr_to_dotted(&(fw->ip.dst)));
else
sprintf(buf, "%s", addr_to_anyname(&(fw->ip.dst)));
strcat(buf, mask_to_dotted(&(fw->ip.dmsk)));
printf(FMT("%-19s ","-> %s"), buf);
}
if (format & FMT_NOTABLE)
fputs(" ", stdout);
#ifdef IPT_F_GOTO
if(fw->ip.flags & IPT_F_GOTO)
printf("[goto] ");
#endif
IPT_MATCH_ITERATE(fw, print_match, &fw->ip, format & FMT_NUMERIC);
if (target) {
if (target->print)
/* Print the target information. */
target->print(&fw->ip, t, format & FMT_NUMERIC);
} else if (t->u.target_size != sizeof(*t))
printf("[%u bytes of unknown target data] ",
(unsigned int)(t->u.target_size - sizeof(*t)));
if (!(format & FMT_NONEWLINE))
fputc('\n', stdout);
}
static void
print_firewall_line(const struct ipt_entry *fw,
const iptc_handle_t h)
{
struct ipt_entry_target *t;
t = ipt_get_target((struct ipt_entry *)fw);
print_firewall(fw, t->u.user.name, 0, FMT_PRINT_RULE, h);
}
static int
append_entry(const ipt_chainlabel chain,
struct ipt_entry *fw,
unsigned int nsaddrs,
const struct in_addr saddrs[],
unsigned int ndaddrs,
const struct in_addr daddrs[],
int verbose,
iptc_handle_t *handle)
{
unsigned int i, j;
int ret = 1;
for (i = 0; i < nsaddrs; i++) {
fw->ip.src.s_addr = saddrs[i].s_addr;
for (j = 0; j < ndaddrs; j++) {
fw->ip.dst.s_addr = daddrs[j].s_addr;
if (verbose)
print_firewall_line(fw, *handle);
ret &= iptc_append_entry(chain, fw, handle);
}
}
return ret;
}
static int
replace_entry(const ipt_chainlabel chain,
struct ipt_entry *fw,
unsigned int rulenum,
const struct in_addr *saddr,
const struct in_addr *daddr,
int verbose,
iptc_handle_t *handle)
{
fw->ip.src.s_addr = saddr->s_addr;
fw->ip.dst.s_addr = daddr->s_addr;
if (verbose)
print_firewall_line(fw, *handle);
return iptc_replace_entry(chain, fw, rulenum, handle);
}
static int
insert_entry(const ipt_chainlabel chain,
struct ipt_entry *fw,
unsigned int rulenum,
unsigned int nsaddrs,
const struct in_addr saddrs[],
unsigned int ndaddrs,
const struct in_addr daddrs[],
int verbose,
iptc_handle_t *handle)
{
unsigned int i, j;
int ret = 1;
for (i = 0; i < nsaddrs; i++) {
fw->ip.src.s_addr = saddrs[i].s_addr;
for (j = 0; j < ndaddrs; j++) {
fw->ip.dst.s_addr = daddrs[j].s_addr;
if (verbose)
print_firewall_line(fw, *handle);
ret &= iptc_insert_entry(chain, fw, rulenum, handle);
}
}
return ret;
}
static unsigned char *
make_delete_mask(struct ipt_entry *fw, struct iptables_rule_match *matches)
{
/* Establish mask for comparison */
unsigned int size;
struct iptables_rule_match *matchp;
unsigned char *mask, *mptr;
size = sizeof(struct ipt_entry);
for (matchp = matches; matchp; matchp = matchp->next)
size += IPT_ALIGN(sizeof(struct ipt_entry_match)) + matchp->match->size;
mask = fw_calloc(1, size
+ IPT_ALIGN(sizeof(struct ipt_entry_target))
+ iptables_targets->size);
memset(mask, 0xFF, sizeof(struct ipt_entry));
mptr = mask + sizeof(struct ipt_entry);
for (matchp = matches; matchp; matchp = matchp->next) {
memset(mptr, 0xFF,
IPT_ALIGN(sizeof(struct ipt_entry_match))
+ matchp->match->userspacesize);
mptr += IPT_ALIGN(sizeof(struct ipt_entry_match)) + matchp->match->size;
}
memset(mptr, 0xFF,
IPT_ALIGN(sizeof(struct ipt_entry_target))
+ iptables_targets->userspacesize);
return mask;
}
static int
delete_entry(const ipt_chainlabel chain,
struct ipt_entry *fw,
unsigned int nsaddrs,
const struct in_addr saddrs[],
unsigned int ndaddrs,
const struct in_addr daddrs[],
int verbose,
iptc_handle_t *handle,
struct iptables_rule_match *matches)
{
unsigned int i, j;
int ret = 1;
unsigned char *mask;
mask = make_delete_mask(fw, matches);
for (i = 0; i < nsaddrs; i++) {
fw->ip.src.s_addr = saddrs[i].s_addr;
for (j = 0; j < ndaddrs; j++) {
fw->ip.dst.s_addr = daddrs[j].s_addr;
if (verbose)
print_firewall_line(fw, *handle);
ret &= iptc_delete_entry(chain, fw, mask, handle);
}
}
free(mask);
return ret;
}
int
for_each_chain(int (*fn)(const ipt_chainlabel, int, iptc_handle_t *),
int verbose, int builtinstoo, iptc_handle_t *handle)
{
int ret = 1;
const char *chain;
char *chains;
unsigned int i, chaincount = 0;
chain = iptc_first_chain(handle);
while (chain) {
chaincount++;
chain = iptc_next_chain(handle);
}
chains = fw_malloc(sizeof(ipt_chainlabel) * chaincount);
i = 0;
chain = iptc_first_chain(handle);
while (chain) {
strcpy(chains + i*sizeof(ipt_chainlabel), chain);
i++;
chain = iptc_next_chain(handle);
}
for (i = 0; i < chaincount; i++) {
if (!builtinstoo
&& iptc_builtin(chains + i*sizeof(ipt_chainlabel),
*handle) == 1)
continue;
ret &= fn(chains + i*sizeof(ipt_chainlabel), verbose, handle);
}
free(chains);
return ret;
}
int
flush_entries(const ipt_chainlabel chain, int verbose,
iptc_handle_t *handle)
{
if (!chain)
return for_each_chain(flush_entries, verbose, 1, handle);
if (verbose)
fprintf(stdout, "Flushing chain `%s'\n", chain);
return iptc_flush_entries(chain, handle);
}
static int
zero_entries(const ipt_chainlabel chain, int verbose,
iptc_handle_t *handle)
{
if (!chain)
return for_each_chain(zero_entries, verbose, 1, handle);
if (verbose)
fprintf(stdout, "Zeroing chain `%s'\n", chain);
return iptc_zero_entries(chain, handle);
}
int
delete_chain(const ipt_chainlabel chain, int verbose,
iptc_handle_t *handle)
{
if (!chain)
return for_each_chain(delete_chain, verbose, 0, handle);
if (verbose)
fprintf(stdout, "Deleting chain `%s'\n", chain);
return iptc_delete_chain(chain, handle);
}
static int
list_entries(const ipt_chainlabel chain, int verbose, int numeric,
int expanded, int linenumbers, iptc_handle_t *handle)
{
int found = 0;
unsigned int format;
const char *this;
format = FMT_OPTIONS;
if (!verbose)
format |= FMT_NOCOUNTS;
else
format |= FMT_VIA;
if (numeric)
format |= FMT_NUMERIC;
if (!expanded)
format |= FMT_KILOMEGAGIGA;
if (linenumbers)
format |= FMT_LINENUMBERS;
for (this = iptc_first_chain(handle);
this;
this = iptc_next_chain(handle)) {
const struct ipt_entry *i;
unsigned int num;
if (chain && strcmp(chain, this) != 0)
continue;
if (found) printf("\n");
print_header(format, this, handle);
i = iptc_first_rule(this, handle);
num = 0;
while (i) {
print_firewall(i,
iptc_get_target(i, handle),
num++,
format,
*handle);
i = iptc_next_rule(i, handle);
}
found = 1;
}
errno = ENOENT;
return found;
}
static char *get_modprobe(void)
{
int procfile;
char *ret;
#define PROCFILE_BUFSIZ 1024
procfile = open(PROC_SYS_MODPROBE, O_RDONLY);
if (procfile < 0)
return NULL;
ret = (char *) malloc(PROCFILE_BUFSIZ);
if (ret) {
memset(ret, 0, PROCFILE_BUFSIZ);
switch (read(procfile, ret, PROCFILE_BUFSIZ)) {
case -1: goto fail;
case PROCFILE_BUFSIZ: goto fail; /* Partial read. Wierd */
}
if (ret[strlen(ret)-1]=='\n')
ret[strlen(ret)-1]=0;
close(procfile);
return ret;
}
fail:
free(ret);
close(procfile);
return NULL;
}
int iptables_insmod(const char *modname, const char *modprobe)
{
char *buf = NULL;
char *argv[3];
int status;
/* If they don't explicitly set it, read out of kernel */
if (!modprobe) {
buf = get_modprobe();
if (!buf)
return -1;
modprobe = buf;
}
switch (fork()) {
case 0:
argv[0] = (char *)modprobe;
argv[1] = (char *)modname;
argv[2] = NULL;
execv(argv[0], argv);
/* not usually reached */
exit(1);
case -1:
return -1;
default: /* parent */
wait(&status);
}
free(buf);
if (WIFEXITED(status) && WEXITSTATUS(status) == 0)
return 0;
return -1;
}
int load_iptables_ko(const char *modprobe)
{
static int loaded = 0;
static int ret = -1;
if (!loaded) {
ret = iptables_insmod("ip_tables", NULL);
loaded = 1;
}
return ret;
}
static struct ipt_entry *
generate_entry(const struct ipt_entry *fw,
struct iptables_rule_match *matches,
struct ipt_entry_target *target)
{
unsigned int size;
struct iptables_rule_match *matchp;
struct ipt_entry *e;
size = sizeof(struct ipt_entry);
for (matchp = matches; matchp; matchp = matchp->next)
size += matchp->match->m->u.match_size;
e = fw_malloc(size + target->u.target_size);
*e = *fw;
e->target_offset = size;
e->next_offset = size + target->u.target_size;
size = 0;
for (matchp = matches; matchp; matchp = matchp->next) {
memcpy(e->elems + size, matchp->match->m, matchp->match->m->u.match_size);
size += matchp->match->m->u.match_size;
}
memcpy(e->elems + size, target, target->u.target_size);
return e;
}
void clear_rule_matches(struct iptables_rule_match **matches)
{
struct iptables_rule_match *matchp, *tmp;
for (matchp = *matches; matchp;) {
tmp = matchp->next;
if (matchp->match->m) {
free(matchp->match->m);
matchp->match->m = NULL;
}
if (matchp->match == matchp->match->next) {
free(matchp->match);
matchp->match = NULL;
}
free(matchp);
matchp = tmp;
}
*matches = NULL;
}
static void set_revision(char *name, u_int8_t revision)
{
/* Old kernel sources don't have ".revision" field,
but we stole a byte from name. */
name[IPT_FUNCTION_MAXNAMELEN - 2] = '\0';
name[IPT_FUNCTION_MAXNAMELEN - 1] = revision;
}
void
get_kernel_version(void) {
static struct utsname uts;
int x = 0, y = 0, z = 0;
if (uname(&uts) == -1) {
fprintf(stderr, "Unable to retrieve kernel version.\n");
free_opts(1);
exit(1);
}
sscanf(uts.release, "%d.%d.%d", &x, &y, &z);
kernel_version = LINUX_VERSION(x, y, z);
}
int do_command(int argc, char *argv[], char **table, iptc_handle_t *handle)
{
struct ipt_entry fw, *e = NULL;
int invert = 0;
unsigned int nsaddrs = 0, ndaddrs = 0;
struct in_addr *saddrs = NULL, *daddrs = NULL;
int c, verbose = 0;
const char *chain = NULL;
const char *shostnetworkmask = NULL, *dhostnetworkmask = NULL;
const char *policy = NULL, *newname = NULL;
unsigned int rulenum = 0, options = 0, command = 0;
const char *pcnt = NULL, *bcnt = NULL;
int ret = 1;
struct iptables_match *m;
struct iptables_rule_match *matches = NULL;
struct iptables_rule_match *matchp;
struct iptables_target *target = NULL;
struct iptables_target *t;
const char *jumpto = "";
char *protocol = NULL;
int proto_used = 0;
memset(&fw, 0, sizeof(fw));
/* re-set optind to 0 in case do_command gets called
* a second time */
optind = 0;
/* clear mflags in case do_command gets called a second time
* (we clear the global list of all matches for security)*/
for (m = iptables_matches; m; m = m->next)
m->mflags = 0;
for (t = iptables_targets; t; t = t->next) {
t->tflags = 0;
t->used = 0;
}
/* Suppress error messages: we may add new options if we
demand-load a protocol. */
opterr = 0;
while ((c = getopt_long(argc, argv,
"-A:D:R:I:L::M:F::Z::N:X::E:P:Vh::o:p:s:d:j:i:fbvnt:m:xc:g:",
opts, NULL)) != -1) {
switch (c) {
/*
* Command selection
*/
case 'A':
add_command(&command, CMD_APPEND, CMD_NONE,
invert);
chain = optarg;
break;
case 'D':
add_command(&command, CMD_DELETE, CMD_NONE,
invert);
chain = optarg;
if (optind < argc && argv[optind][0] != '-'
&& argv[optind][0] != '!') {
rulenum = parse_rulenumber(argv[optind++]);
command = CMD_DELETE_NUM;
}
break;
case 'R':
add_command(&command, CMD_REPLACE, CMD_NONE,
invert);
chain = optarg;
if (optind < argc && argv[optind][0] != '-'
&& argv[optind][0] != '!')
rulenum = parse_rulenumber(argv[optind++]);
else
exit_error(PARAMETER_PROBLEM,
"-%c requires a rule number",
cmd2char(CMD_REPLACE));
break;
case 'I':
add_command(&command, CMD_INSERT, CMD_NONE,
invert);
chain = optarg;
if (optind < argc && argv[optind][0] != '-'
&& argv[optind][0] != '!')
rulenum = parse_rulenumber(argv[optind++]);
else rulenum = 1;
break;
case 'L':
add_command(&command, CMD_LIST, CMD_ZERO,
invert);
if (optarg) chain = optarg;
else if (optind < argc && argv[optind][0] != '-'
&& argv[optind][0] != '!')
chain = argv[optind++];
break;
case 'F':
add_command(&command, CMD_FLUSH, CMD_NONE,
invert);
if (optarg) chain = optarg;
else if (optind < argc && argv[optind][0] != '-'
&& argv[optind][0] != '!')
chain = argv[optind++];
break;
case 'Z':
add_command(&command, CMD_ZERO, CMD_LIST,
invert);
if (optarg) chain = optarg;
else if (optind < argc && argv[optind][0] != '-'
&& argv[optind][0] != '!')
chain = argv[optind++];
break;
case 'N':
if (optarg && (*optarg == '-' || *optarg == '!'))
exit_error(PARAMETER_PROBLEM,
"chain name not allowed to start "
"with `%c'\n", *optarg);
if (find_target(optarg, TRY_LOAD))
exit_error(PARAMETER_PROBLEM,
"chain name may not clash "
"with target name\n");
add_command(&command, CMD_NEW_CHAIN, CMD_NONE,
invert);
chain = optarg;
break;
case 'X':
add_command(&command, CMD_DELETE_CHAIN, CMD_NONE,
invert);
if (optarg) chain = optarg;
else if (optind < argc && argv[optind][0] != '-'
&& argv[optind][0] != '!')
chain = argv[optind++];
break;
case 'E':
add_command(&command, CMD_RENAME_CHAIN, CMD_NONE,
invert);
chain = optarg;
if (optind < argc && argv[optind][0] != '-'
&& argv[optind][0] != '!')
newname = argv[optind++];
else
exit_error(PARAMETER_PROBLEM,
"-%c requires old-chain-name and "
"new-chain-name",
cmd2char(CMD_RENAME_CHAIN));
break;
case 'P':
add_command(&command, CMD_SET_POLICY, CMD_NONE,
invert);
chain = optarg;
if (optind < argc && argv[optind][0] != '-'
&& argv[optind][0] != '!')
policy = argv[optind++];
else
exit_error(PARAMETER_PROBLEM,
"-%c requires a chain and a policy",
cmd2char(CMD_SET_POLICY));
break;
case 'h':
if (!optarg)
optarg = argv[optind];
/* iptables -p icmp -h */
if (!matches && protocol)
find_match(protocol, TRY_LOAD, &matches);
exit_printhelp(matches);
/*
* Option selection
*/
case 'p':
check_inverse(optarg, &invert, &optind, argc);
set_option(&options, OPT_PROTOCOL, &fw.ip.invflags,
invert);
/* Canonicalize into lower case */
for (protocol = argv[optind-1]; *protocol; protocol++)
*protocol = tolower(*protocol);
protocol = argv[optind-1];
fw.ip.proto = parse_protocol(protocol);
if (fw.ip.proto == 0
&& (fw.ip.invflags & IPT_INV_PROTO))
exit_error(PARAMETER_PROBLEM,
"rule would never match protocol");
break;
case 's':
check_inverse(optarg, &invert, &optind, argc);
set_option(&options, OPT_SOURCE, &fw.ip.invflags,
invert);
shostnetworkmask = argv[optind-1];
break;
case 'd':
check_inverse(optarg, &invert, &optind, argc);
set_option(&options, OPT_DESTINATION, &fw.ip.invflags,
invert);
dhostnetworkmask = argv[optind-1];
break;
#ifdef IPT_F_GOTO
case 'g':
set_option(&options, OPT_JUMP, &fw.ip.invflags,
invert);
fw.ip.flags |= IPT_F_GOTO;
jumpto = parse_target(optarg);
break;
#endif
case 'j':
set_option(&options, OPT_JUMP, &fw.ip.invflags,
invert);
jumpto = parse_target(optarg);
/* TRY_LOAD (may be chain name) */
target = find_target(jumpto, TRY_LOAD);
if (target) {
size_t size;
size = IPT_ALIGN(sizeof(struct ipt_entry_target))
+ target->size;
target->t = fw_calloc(1, size);
target->t->u.target_size = size;
strcpy(target->t->u.user.name, jumpto);
set_revision(target->t->u.user.name,
target->revision);
if (target->init != NULL)
target->init(target->t, &fw.nfcache);
opts = merge_options(opts, target->extra_opts, &target->option_offset);
}
break;
case 'i':
check_inverse(optarg, &invert, &optind, argc);
set_option(&options, OPT_VIANAMEIN, &fw.ip.invflags,
invert);
parse_interface(argv[optind-1],
fw.ip.iniface,
fw.ip.iniface_mask);
break;
case 'o':
check_inverse(optarg, &invert, &optind, argc);
set_option(&options, OPT_VIANAMEOUT, &fw.ip.invflags,
invert);
parse_interface(argv[optind-1],
fw.ip.outiface,
fw.ip.outiface_mask);
break;
case 'f':
set_option(&options, OPT_FRAGMENT, &fw.ip.invflags,
invert);
fw.ip.flags |= IPT_F_FRAG;
break;
case 'v':
if (!verbose)
set_option(&options, OPT_VERBOSE,
&fw.ip.invflags, invert);
verbose++;
break;
case 'm': {
size_t size;
if (invert)
exit_error(PARAMETER_PROBLEM,
"unexpected ! flag before --match");
m = find_match(optarg, LOAD_MUST_SUCCEED, &matches);
size = IPT_ALIGN(sizeof(struct ipt_entry_match))
+ m->size;
m->m = fw_calloc(1, size);
m->m->u.match_size = size;
strcpy(m->m->u.user.name, m->name);
set_revision(m->m->u.user.name, m->revision);
if (m->init != NULL)
m->init(m->m, &fw.nfcache);
if (m != m->next)
/* Merge options for non-cloned matches */
opts = merge_options(opts, m->extra_opts, &m->option_offset);
}
break;
case 'n':
set_option(&options, OPT_NUMERIC, &fw.ip.invflags,
invert);
break;
case 't':
if (invert)
exit_error(PARAMETER_PROBLEM,
"unexpected ! flag before --table");
*table = argv[optind-1];
break;
case 'x':
set_option(&options, OPT_EXPANDED, &fw.ip.invflags,
invert);
break;
case 'V':
if (invert)
printf("Not %s ;-)\n", program_version);
else
printf("%s v%s\n",
program_name, program_version);
exit(0);
case '0':
set_option(&options, OPT_LINENUMBERS, &fw.ip.invflags,
invert);
break;
case 'M':
modprobe = optarg;
break;
case 'c':
set_option(&options, OPT_COUNTERS, &fw.ip.invflags,
invert);
pcnt = optarg;
if (optind < argc && argv[optind][0] != '-'
&& argv[optind][0] != '!')
bcnt = argv[optind++];
else
exit_error(PARAMETER_PROBLEM,
"-%c requires packet and byte counter",
opt2char(OPT_COUNTERS));
if (sscanf(pcnt, "%llu", (unsigned long long *)&fw.counters.pcnt) != 1)
exit_error(PARAMETER_PROBLEM,
"-%c packet counter not numeric",
opt2char(OPT_COUNTERS));
if (sscanf(bcnt, "%llu", (unsigned long long *)&fw.counters.bcnt) != 1)
exit_error(PARAMETER_PROBLEM,
"-%c byte counter not numeric",
opt2char(OPT_COUNTERS));
break;
case 1: /* non option */
if (optarg[0] == '!' && optarg[1] == '\0') {
if (invert)
exit_error(PARAMETER_PROBLEM,
"multiple consecutive ! not"
" allowed");
invert = TRUE;
optarg[0] = '\0';
continue;
}
printf("Bad argument `%s'\n", optarg);
exit_tryhelp(2);
default:
if (!target
|| !(target->parse(c - target->option_offset,
argv, invert,
&target->tflags,
&fw, &target->t))) {
for (matchp = matches; matchp; matchp = matchp->next) {
if (matchp->completed)
continue;
if (matchp->match->parse(c - matchp->match->option_offset,
argv, invert,
&matchp->match->mflags,
&fw,
&fw.nfcache,
&matchp->match->m))
break;
}
m = matchp ? matchp->match : NULL;
/* If you listen carefully, you can
actually hear this code suck. */
/* some explanations (after four different bugs
* in 3 different releases): If we encounter a
* parameter, that has not been parsed yet,
* it's not an option of an explicitly loaded
* match or a target. However, we support
* implicit loading of the protocol match
* extension. '-p tcp' means 'l4 proto 6' and
* at the same time 'load tcp protocol match on
* demand if we specify --dport'.
*
* To make this work, we need to make sure:
* - the parameter has not been parsed by
* a match (m above)
* - a protocol has been specified
* - the protocol extension has not been
* loaded yet, or is loaded and unused
* [think of iptables-restore!]
* - the protocol extension can be successively
* loaded
*/
if (m == NULL
&& protocol
&& (!find_proto(protocol, DONT_LOAD,
options&OPT_NUMERIC, NULL)
|| (find_proto(protocol, DONT_LOAD,
options&OPT_NUMERIC, NULL)
&& (proto_used == 0))
)
&& (m = find_proto(protocol, TRY_LOAD,
options&OPT_NUMERIC, &matches))) {
/* Try loading protocol */
size_t size;
proto_used = 1;
size = IPT_ALIGN(sizeof(struct ipt_entry_match))
+ m->size;
m->m = fw_calloc(1, size);
m->m->u.match_size = size;
strcpy(m->m->u.user.name, m->name);
set_revision(m->m->u.user.name,
m->revision);
if (m->init != NULL)
m->init(m->m, &fw.nfcache);
opts = merge_options(opts,
m->extra_opts, &m->option_offset);
optind--;
continue;
}
if (!m)
exit_error(PARAMETER_PROBLEM,
"Unknown arg `%s'",
argv[optind-1]);
}
}
invert = FALSE;
}
for (matchp = matches; matchp; matchp = matchp->next)
matchp->match->final_check(matchp->match->mflags);
if (target)
target->final_check(target->tflags);
/* Fix me: must put inverse options checking here --MN */
if (optind < argc)
exit_error(PARAMETER_PROBLEM,
"unknown arguments found on commandline");
if (!command)
exit_error(PARAMETER_PROBLEM, "no command specified");
if (invert)
exit_error(PARAMETER_PROBLEM,
"nothing appropriate following !");
if (command & (CMD_REPLACE | CMD_INSERT | CMD_DELETE | CMD_APPEND)) {
if (!(options & OPT_DESTINATION))
dhostnetworkmask = "0.0.0.0/0";
if (!(options & OPT_SOURCE))
shostnetworkmask = "0.0.0.0/0";
}
if (shostnetworkmask)
parse_hostnetworkmask(shostnetworkmask, &saddrs,
&(fw.ip.smsk), &nsaddrs);
if (dhostnetworkmask)
parse_hostnetworkmask(dhostnetworkmask, &daddrs,
&(fw.ip.dmsk), &ndaddrs);
if ((nsaddrs > 1 || ndaddrs > 1) &&
(fw.ip.invflags & (IPT_INV_SRCIP | IPT_INV_DSTIP)))
exit_error(PARAMETER_PROBLEM, "! not allowed with multiple"
" source or destination IP addresses");
if (command == CMD_REPLACE && (nsaddrs != 1 || ndaddrs != 1))
exit_error(PARAMETER_PROBLEM, "Replacement rule does not "
"specify a unique address");
generic_opt_check(command, options);
if (chain && strlen(chain) > IPT_FUNCTION_MAXNAMELEN)
exit_error(PARAMETER_PROBLEM,
"chain name `%s' too long (must be under %i chars)",
chain, IPT_FUNCTION_MAXNAMELEN);
/* only allocate handle if we weren't called with a handle */
if (!*handle)
*handle = iptc_init(*table);
/* try to insmod the module if iptc_init failed */
if (!*handle && load_iptables_ko(modprobe) != -1)
*handle = iptc_init(*table);
if (!*handle)
exit_error(VERSION_PROBLEM,
"can't initialize iptables table `%s': %s",
*table, iptc_strerror(errno));
if (command == CMD_APPEND
|| command == CMD_DELETE
|| command == CMD_INSERT
|| command == CMD_REPLACE) {
if (strcmp(chain, "PREROUTING") == 0
|| strcmp(chain, "INPUT") == 0) {
/* -o not valid with incoming packets. */
if (options & OPT_VIANAMEOUT)
exit_error(PARAMETER_PROBLEM,
"Can't use -%c with %s\n",
opt2char(OPT_VIANAMEOUT),
chain);
}
if (strcmp(chain, "POSTROUTING") == 0
|| strcmp(chain, "OUTPUT") == 0) {
/* -i not valid with outgoing packets */
if (options & OPT_VIANAMEIN)
exit_error(PARAMETER_PROBLEM,
"Can't use -%c with %s\n",
opt2char(OPT_VIANAMEIN),
chain);
}
if (target && iptc_is_chain(jumpto, *handle)) {
printf("Warning: using chain %s, not extension\n",
jumpto);
if (target->t)
free(target->t);
target = NULL;
}
/* If they didn't specify a target, or it's a chain
name, use standard. */
if (!target
&& (strlen(jumpto) == 0
|| iptc_is_chain(jumpto, *handle))) {
size_t size;
target = find_target(IPT_STANDARD_TARGET,
LOAD_MUST_SUCCEED);
size = sizeof(struct ipt_entry_target)
+ target->size;
target->t = fw_calloc(1, size);
target->t->u.target_size = size;
strcpy(target->t->u.user.name, jumpto);
if (!iptc_is_chain(jumpto, *handle))
set_revision(target->t->u.user.name,
target->revision);
if (target->init != NULL)
target->init(target->t, &fw.nfcache);
}
if (!target) {
/* it is no chain, and we can't load a plugin.
* We cannot know if the plugin is corrupt, non
* existant OR if the user just misspelled a
* chain. */
#ifdef IPT_F_GOTO
if (fw.ip.flags & IPT_F_GOTO)
exit_error(PARAMETER_PROBLEM,
"goto '%s' is not a chain\n", jumpto);
#endif
find_target(jumpto, LOAD_MUST_SUCCEED);
} else {
e = generate_entry(&fw, matches, target->t);
free(target->t);
}
}
switch (command) {
case CMD_APPEND:
ret = append_entry(chain, e,
nsaddrs, saddrs, ndaddrs, daddrs,
options&OPT_VERBOSE,
handle);
break;
case CMD_DELETE:
ret = delete_entry(chain, e,
nsaddrs, saddrs, ndaddrs, daddrs,
options&OPT_VERBOSE,
handle, matches);
break;
case CMD_DELETE_NUM:
ret = iptc_delete_num_entry(chain, rulenum - 1, handle);
break;
case CMD_REPLACE:
ret = replace_entry(chain, e, rulenum - 1,
saddrs, daddrs, options&OPT_VERBOSE,
handle);
break;
case CMD_INSERT:
ret = insert_entry(chain, e, rulenum - 1,
nsaddrs, saddrs, ndaddrs, daddrs,
options&OPT_VERBOSE,
handle);
break;
case CMD_LIST:
ret = list_entries(chain,
options&OPT_VERBOSE,
options&OPT_NUMERIC,
options&OPT_EXPANDED,
options&OPT_LINENUMBERS,
handle);
break;
case CMD_FLUSH:
ret = flush_entries(chain, options&OPT_VERBOSE, handle);
break;
case CMD_ZERO:
ret = zero_entries(chain, options&OPT_VERBOSE, handle);
break;
case CMD_LIST|CMD_ZERO:
ret = list_entries(chain,
options&OPT_VERBOSE,
options&OPT_NUMERIC,
options&OPT_EXPANDED,
options&OPT_LINENUMBERS,
handle);
if (ret)
ret = zero_entries(chain,
options&OPT_VERBOSE, handle);
break;
case CMD_NEW_CHAIN:
ret = iptc_create_chain(chain, handle);
break;
case CMD_DELETE_CHAIN:
ret = delete_chain(chain, options&OPT_VERBOSE, handle);
break;
case CMD_RENAME_CHAIN:
ret = iptc_rename_chain(chain, newname, handle);
break;
case CMD_SET_POLICY:
ret = iptc_set_policy(chain, policy, NULL, handle);
break;
default:
/* We should never reach this... */
exit_tryhelp(2);
}
if (verbose > 1)
dump_entries(*handle);
clear_rule_matches(&matches);
if (e != NULL) {
free(e);
e = NULL;
}
free(saddrs);
free(daddrs);
free_opts(1);
return ret;
}