/* Code to restore the iptables state, from file by ip6tables-save.
* Author: Andras Kis-Szabo <kisza@sch.bme.hu>
*
* based on iptables-restore
* Authors:
* Harald Welte <laforge@gnumonks.org>
* Rusty Russell <rusty@linuxcare.com.au>
* This code is distributed under the terms of GNU GPL v2
*/
#include <getopt.h>
#include <sys/errno.h>
#include <stdbool.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include "ip6tables.h"
#include "xshared.h"
#include "xtables.h"
#include "libiptc/libip6tc.h"
#include "ip6tables-multi.h"
#ifdef DEBUG
#define DEBUGP(x, args...) fprintf(stderr, x, ## args)
#else
#define DEBUGP(x, args...)
#endif
static int binary = 0, counters = 0, verbose = 0, noflush = 0, wait = 0;
/* Keeping track of external matches and targets. */
static const struct option options[] = {
{.name = "binary", .has_arg = false, .val = 'b'},
{.name = "counters", .has_arg = false, .val = 'c'},
{.name = "verbose", .has_arg = false, .val = 'v'},
{.name = "test", .has_arg = false, .val = 't'},
{.name = "help", .has_arg = false, .val = 'h'},
{.name = "noflush", .has_arg = false, .val = 'n'},
{.name = "wait", .has_arg = false, .val = 'w'},
{.name = "modprobe", .has_arg = true, .val = 'M'},
{.name = "table", .has_arg = true, .val = 'T'},
{NULL},
};
static void print_usage(const char *name, const char *version) __attribute__((noreturn));
static void print_usage(const char *name, const char *version)
{
fprintf(stderr, "Usage: %s [-b] [-c] [-v] [-t] [-h] [-w]\n"
" [ --binary ]\n"
" [ --counters ]\n"
" [ --verbose ]\n"
" [ --test ]\n"
" [ --help ]\n"
" [ --noflush ]\n"
" [ --wait ]\n"
" [ --modprobe=<command>]\n", name);
exit(1);
}
static struct xtc_handle *create_handle(const char *tablename)
{
struct xtc_handle *handle;
handle = ip6tc_init(tablename);
if (!handle) {
/* try to insmod the module if iptc_init failed */
xtables_load_ko(xtables_modprobe_program, false);
handle = ip6tc_init(tablename);
}
if (!handle) {
xtables_error(PARAMETER_PROBLEM, "%s: unable to initialize "
"table '%s'\n", ip6tables_globals.program_name,
tablename);
exit(1);
}
return handle;
}
static int parse_counters(char *string, struct xt_counters *ctr)
{
unsigned long long pcnt, bcnt;
int ret;
ret = sscanf(string, "[%llu:%llu]", &pcnt, &bcnt);
ctr->pcnt = pcnt;
ctr->bcnt = bcnt;
return ret == 2;
}
/* global new argv and argc */
static char *newargv[255];
static int newargc;
/* function adding one argument to newargv, updating newargc
* returns true if argument added, false otherwise */
static int add_argv(char *what) {
DEBUGP("add_argv: %s\n", what);
if (what && newargc + 1 < ARRAY_SIZE(newargv)) {
newargv[newargc] = strdup(what);
newargv[++newargc] = NULL;
return 1;
} else {
xtables_error(PARAMETER_PROBLEM,
"Parser cannot handle more arguments\n");
return 0;
}
}
static void free_argv(void) {
int i;
for (i = 0; i < newargc; i++)
free(newargv[i]);
}
static void add_param_to_argv(char *parsestart)
{
int quote_open = 0, escaped = 0, param_len = 0;
char param_buffer[1024], *curchar;
/* After fighting with strtok enough, here's now
* a 'real' parser. According to Rusty I'm now no
* longer a real hacker, but I can live with that */
for (curchar = parsestart; *curchar; curchar++) {
if (quote_open) {
if (escaped) {
param_buffer[param_len++] = *curchar;
escaped = 0;
continue;
} else if (*curchar == '\\') {
escaped = 1;
continue;
} else if (*curchar == '"') {
quote_open = 0;
*curchar = ' ';
} else {
param_buffer[param_len++] = *curchar;
continue;
}
} else {
if (*curchar == '"') {
quote_open = 1;
continue;
}
}
if (*curchar == ' '
|| *curchar == '\t'
|| * curchar == '\n') {
if (!param_len) {
/* two spaces? */
continue;
}
param_buffer[param_len] = '\0';
/* check if table name specified */
if (!strncmp(param_buffer, "-t", 2)
|| !strncmp(param_buffer, "--table", 8)) {
xtables_error(PARAMETER_PROBLEM,
"The -t option (seen in line %u) cannot be "
"used in ip6tables-restore.\n", line);
exit(1);
}
add_argv(param_buffer);
param_len = 0;
} else {
/* regular character, copy to buffer */
param_buffer[param_len++] = *curchar;
if (param_len >= sizeof(param_buffer))
xtables_error(PARAMETER_PROBLEM,
"Parameter too long!");
}
}
}
int ip6tables_restore_main(int argc, char *argv[])
{
struct xtc_handle *handle = NULL;
char buffer[10240];
int c;
char curtable[XT_TABLE_MAXNAMELEN + 1];
FILE *in;
int in_table = 0, testing = 0;
const char *tablename = NULL;
const struct xtc_ops *ops = &ip6tc_ops;
line = 0;
ip6tables_globals.program_name = "ip6tables-restore";
c = xtables_init_all(&ip6tables_globals, NFPROTO_IPV6);
if (c < 0) {
fprintf(stderr, "%s/%s Failed to initialize xtables\n",
ip6tables_globals.program_name,
ip6tables_globals.program_version);
exit(1);
}
#if defined(ALL_INCLUSIVE) || defined(NO_SHARED_LIBS)
init_extensions();
init_extensions6();
#endif
while ((c = getopt_long(argc, argv, "bcvthnwM:T:", options, NULL)) != -1) {
switch (c) {
case 'b':
binary = 1;
break;
case 'c':
counters = 1;
break;
case 'v':
verbose = 1;
break;
case 't':
testing = 1;
break;
case 'h':
print_usage("ip6tables-restore",
IPTABLES_VERSION);
break;
case 'n':
noflush = 1;
break;
case 'w':
wait = 1;
break;
case 'M':
xtables_modprobe_program = optarg;
break;
case 'T':
tablename = optarg;
break;
}
}
if (optind == argc - 1) {
in = fopen(argv[optind], "re");
if (!in) {
fprintf(stderr, "Can't open %s: %s\n", argv[optind],
strerror(errno));
exit(1);
}
}
else if (optind < argc) {
fprintf(stderr, "Unknown arguments found on commandline\n");
exit(1);
}
else in = stdin;
if (!xtables_lock(wait)) {
fprintf(stderr, "Another app is currently holding the xtables lock. "
"Perhaps you want to use the -w option?\n");
exit(RESOURCE_PROBLEM);
}
/* Grab standard input. */
while (fgets(buffer, sizeof(buffer), in)) {
int ret = 0;
line++;
if (buffer[0] == '\n')
continue;
else if (buffer[0] == '#') {
if (verbose)
fputs(buffer, stdout);
continue;
} else if ((strcmp(buffer, "COMMIT\n") == 0) && (in_table)) {
if (!testing) {
DEBUGP("Calling commit\n");
ret = ops->commit(handle);
ops->free(handle);
handle = NULL;
} else {
DEBUGP("Not calling commit, testing\n");
ret = 1;
}
in_table = 0;
} else if ((buffer[0] == '*') && (!in_table)) {
/* New table */
char *table;
table = strtok(buffer+1, " \t\n");
DEBUGP("line %u, table '%s'\n", line, table);
if (!table) {
xtables_error(PARAMETER_PROBLEM,
"%s: line %u table name invalid\n",
xt_params->program_name, line);
exit(1);
}
strncpy(curtable, table, XT_TABLE_MAXNAMELEN);
curtable[XT_TABLE_MAXNAMELEN] = '\0';
if (tablename != NULL && strcmp(tablename, table) != 0)
continue;
if (handle)
ops->free(handle);
handle = create_handle(table);
if (noflush == 0) {
DEBUGP("Cleaning all chains of table '%s'\n",
table);
for_each_chain6(flush_entries6, verbose, 1,
handle);
DEBUGP("Deleting all user-defined chains "
"of table '%s'\n", table);
for_each_chain6(delete_chain6, verbose, 0,
handle);
}
ret = 1;
in_table = 1;
} else if ((buffer[0] == ':') && (in_table)) {
/* New chain. */
char *policy, *chain;
chain = strtok(buffer+1, " \t\n");
DEBUGP("line %u, chain '%s'\n", line, chain);
if (!chain) {
xtables_error(PARAMETER_PROBLEM,
"%s: line %u chain name invalid\n",
xt_params->program_name, line);
exit(1);
}
if (strlen(chain) >= XT_EXTENSION_MAXNAMELEN)
xtables_error(PARAMETER_PROBLEM,
"Invalid chain name `%s' "
"(%u chars max)",
chain, XT_EXTENSION_MAXNAMELEN - 1);
if (ops->builtin(chain, handle) <= 0) {
if (noflush && ops->is_chain(chain, handle)) {
DEBUGP("Flushing existing user defined chain '%s'\n", chain);
if (!ops->flush_entries(chain, handle))
xtables_error(PARAMETER_PROBLEM,
"error flushing chain "
"'%s':%s\n", chain,
strerror(errno));
} else {
DEBUGP("Creating new chain '%s'\n", chain);
if (!ops->create_chain(chain, handle))
xtables_error(PARAMETER_PROBLEM,
"error creating chain "
"'%s':%s\n", chain,
strerror(errno));
}
}
policy = strtok(NULL, " \t\n");
DEBUGP("line %u, policy '%s'\n", line, policy);
if (!policy) {
xtables_error(PARAMETER_PROBLEM,
"%s: line %u policy invalid\n",
xt_params->program_name, line);
exit(1);
}
if (strcmp(policy, "-") != 0) {
struct xt_counters count;
if (counters) {
char *ctrs;
ctrs = strtok(NULL, " \t\n");
if (!ctrs || !parse_counters(ctrs, &count))
xtables_error(PARAMETER_PROBLEM,
"invalid policy counters "
"for chain '%s'\n", chain);
} else {
memset(&count, 0, sizeof(count));
}
DEBUGP("Setting policy of chain %s to %s\n",
chain, policy);
if (!ops->set_policy(chain, policy, &count,
handle))
xtables_error(OTHER_PROBLEM,
"Can't set policy `%s'"
" on `%s' line %u: %s\n",
policy, chain, line,
ops->strerror(errno));
}
ret = 1;
} else if (in_table) {
int a;
char *ptr = buffer;
char *pcnt = NULL;
char *bcnt = NULL;
char *parsestart;
/* reset the newargv */
newargc = 0;
if (buffer[0] == '[') {
/* we have counters in our input */
ptr = strchr(buffer, ']');
if (!ptr)
xtables_error(PARAMETER_PROBLEM,
"Bad line %u: need ]\n",
line);
pcnt = strtok(buffer+1, ":");
if (!pcnt)
xtables_error(PARAMETER_PROBLEM,
"Bad line %u: need :\n",
line);
bcnt = strtok(NULL, "]");
if (!bcnt)
xtables_error(PARAMETER_PROBLEM,
"Bad line %u: need ]\n",
line);
/* start command parsing after counter */
parsestart = ptr + 1;
} else {
/* start command parsing at start of line */
parsestart = buffer;
}
add_argv(argv[0]);
add_argv("-t");
add_argv(curtable);
if (counters && pcnt && bcnt) {
add_argv("--set-counters");
add_argv((char *) pcnt);
add_argv((char *) bcnt);
}
add_param_to_argv(parsestart);
DEBUGP("calling do_command6(%u, argv, &%s, handle):\n",
newargc, curtable);
for (a = 0; a < newargc; a++)
DEBUGP("argv[%u]: %s\n", a, newargv[a]);
ret = do_command6(newargc, newargv,
&newargv[2], &handle, true);
free_argv();
fflush(stdout);
}
if (tablename != NULL && strcmp(tablename, curtable) != 0)
continue;
if (!ret) {
fprintf(stderr, "%s: line %u failed\n",
xt_params->program_name, line);
exit(1);
}
}
if (in_table) {
fprintf(stderr, "%s: COMMIT expected at line %u\n",
xt_params->program_name, line + 1);
exit(1);
}
fclose(in);
return 0;
}