blob: 35fa6258af79be08a9a9141fc611da073b039f7a [file] [log] [blame]
/*
* (C) 2000-2006 by the netfilter coreteam <coreteam@netfilter.org>:
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include "config.h"
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <netdb.h>
#include <spawn.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/statfs.h>
#include <sys/types.h>
#include <sys/utsname.h>
#include <sys/wait.h>
#include <arpa/inet.h>
#if defined(HAVE_LINUX_MAGIC_H)
# include <linux/magic.h> /* for PROC_SUPER_MAGIC */
#elif defined(HAVE_LINUX_PROC_FS_H)
# include <linux/proc_fs.h> /* Linux 2.4 */
#else
# define PROC_SUPER_MAGIC 0x9fa0
#endif
#include <xtables.h>
#include <limits.h> /* INT_MAX in ip_tables.h/ip6_tables.h */
#ifdef __BIONIC__
#include <linux/if_ether.h> /* ETH_ALEN */
#endif
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <libiptc/libxtc.h>
#ifndef NO_SHARED_LIBS
#include <dlfcn.h>
#endif
#ifndef IPT_SO_GET_REVISION_MATCH /* Old kernel source. */
# define IPT_SO_GET_REVISION_MATCH (IPT_BASE_CTL + 2)
# define IPT_SO_GET_REVISION_TARGET (IPT_BASE_CTL + 3)
#endif
#ifndef IP6T_SO_GET_REVISION_MATCH /* Old kernel source. */
# define IP6T_SO_GET_REVISION_MATCH 68
# define IP6T_SO_GET_REVISION_TARGET 69
#endif
#include <getopt.h>
#include "iptables/internal.h"
#include "xshared.h"
#define NPROTO 255
#ifndef PROC_SYS_MODPROBE
#define PROC_SYS_MODPROBE "/proc/sys/kernel/modprobe"
#endif
/* we need this for ip6?tables-restore. ip6?tables-restore.c sets line to the
* current line of the input file, in order to give a more precise error
* message. ip6?tables itself doesn't need this, so it is initialized to the
* magic number of -1 */
int line = -1;
void basic_exit_err(enum xtables_exittype status, const char *msg, ...) __attribute__((noreturn, format(printf,2,3)));
struct xtables_globals *xt_params = NULL;
void basic_exit_err(enum xtables_exittype status, const char *msg, ...)
{
va_list args;
va_start(args, msg);
fprintf(stderr, "%s v%s: ", xt_params->program_name, xt_params->program_version);
vfprintf(stderr, msg, args);
va_end(args);
fprintf(stderr, "\n");
exit(status);
}
void xtables_free_opts(int unused)
{
if (xt_params->opts != xt_params->orig_opts) {
free(xt_params->opts);
xt_params->opts = NULL;
}
}
struct option *xtables_merge_options(struct option *orig_opts,
struct option *oldopts,
const struct option *newopts,
unsigned int *option_offset)
{
unsigned int num_oold = 0, num_old = 0, num_new = 0, i;
struct option *merge, *mp;
if (newopts == NULL)
return oldopts;
for (num_oold = 0; orig_opts[num_oold].name; num_oold++) ;
if (oldopts != NULL)
for (num_old = 0; oldopts[num_old].name; num_old++) ;
for (num_new = 0; newopts[num_new].name; num_new++) ;
/*
* Since @oldopts also has @orig_opts already (and does so at the
* start), skip these entries.
*/
if (oldopts != NULL) {
oldopts += num_oold;
num_old -= num_oold;
}
merge = malloc(sizeof(*mp) * (num_oold + num_old + num_new + 1));
if (merge == NULL)
return NULL;
/* Let the base options -[ADI...] have precedence over everything */
memcpy(merge, orig_opts, sizeof(*mp) * num_oold);
mp = merge + num_oold;
/* Second, the new options */
xt_params->option_offset += XT_OPTION_OFFSET_SCALE;
*option_offset = xt_params->option_offset;
memcpy(mp, newopts, sizeof(*mp) * num_new);
for (i = 0; i < num_new; ++i, ++mp)
mp->val += *option_offset;
/* Third, the old options */
if (oldopts != NULL) {
memcpy(mp, oldopts, sizeof(*mp) * num_old);
mp += num_old;
}
xtables_free_opts(0);
/* Clear trailing entry */
memset(mp, 0, sizeof(*mp));
return merge;
}
static const struct xtables_afinfo afinfo_ipv4 = {
.kmod = "ip_tables",
.proc_exists = "/proc/net/ip_tables_names",
.libprefix = "libipt_",
.family = NFPROTO_IPV4,
.ipproto = IPPROTO_IP,
.so_rev_match = IPT_SO_GET_REVISION_MATCH,
.so_rev_target = IPT_SO_GET_REVISION_TARGET,
};
static const struct xtables_afinfo afinfo_ipv6 = {
.kmod = "ip6_tables",
.proc_exists = "/proc/net/ip6_tables_names",
.libprefix = "libip6t_",
.family = NFPROTO_IPV6,
.ipproto = IPPROTO_IPV6,
.so_rev_match = IP6T_SO_GET_REVISION_MATCH,
.so_rev_target = IP6T_SO_GET_REVISION_TARGET,
};
/* Dummy families for arptables-compat and ebtables-compat. Leave structure
* fields that we don't use unset.
*/
static const struct xtables_afinfo afinfo_bridge = {
.libprefix = "libebt_",
.family = NFPROTO_BRIDGE,
};
static const struct xtables_afinfo afinfo_arp = {
.libprefix = "libarpt_",
.family = NFPROTO_ARP,
};
const struct xtables_afinfo *afinfo;
/* Search path for Xtables .so files */
static const char *xtables_libdir;
/* the path to command to load kernel module */
const char *xtables_modprobe_program;
/* Keep track of matches/targets pending full registration: linked lists. */
struct xtables_match *xtables_pending_matches;
struct xtables_target *xtables_pending_targets;
/* Keep track of fully registered external matches/targets: linked lists. */
struct xtables_match *xtables_matches;
struct xtables_target *xtables_targets;
/* Fully register a match/target which was previously partially registered. */
static bool xtables_fully_register_pending_match(struct xtables_match *me,
struct xtables_match *prev);
static bool xtables_fully_register_pending_target(struct xtables_target *me,
struct xtables_target *prev);
#ifndef NO_SHARED_LIBS
/* registry for loaded shared objects to close later */
struct dlreg {
struct dlreg *next;
void *handle;
};
static struct dlreg *dlreg = NULL;
static int dlreg_add(void *handle)
{
struct dlreg *new = malloc(sizeof(*new));
if (!new)
return -1;
new->handle = handle;
new->next = dlreg;
dlreg = new;
return 0;
}
static void dlreg_free(void)
{
struct dlreg *next;
while (dlreg) {
next = dlreg->next;
dlclose(dlreg->handle);
free(dlreg);
dlreg = next;
}
}
#endif
void xtables_init(void)
{
xtables_libdir = getenv("XTABLES_LIBDIR");
if (xtables_libdir != NULL)
return;
xtables_libdir = getenv("IPTABLES_LIB_DIR");
if (xtables_libdir != NULL) {
fprintf(stderr, "IPTABLES_LIB_DIR is deprecated, "
"use XTABLES_LIBDIR.\n");
return;
}
/*
* Well yes, IP6TABLES_LIB_DIR is of lower priority over
* IPTABLES_LIB_DIR since this moved to libxtables; I think that is ok
* for these env vars are deprecated anyhow, and in light of the
* (shared) libxt_*.so files, makes less sense to have
* IPTABLES_LIB_DIR != IP6TABLES_LIB_DIR.
*/
xtables_libdir = getenv("IP6TABLES_LIB_DIR");
if (xtables_libdir != NULL) {
fprintf(stderr, "IP6TABLES_LIB_DIR is deprecated, "
"use XTABLES_LIBDIR.\n");
return;
}
xtables_libdir = XTABLES_LIBDIR;
}
void xtables_fini(void)
{
#ifndef NO_SHARED_LIBS
dlreg_free();
#endif
}
void xtables_set_nfproto(uint8_t nfproto)
{
switch (nfproto) {
case NFPROTO_IPV4:
afinfo = &afinfo_ipv4;
break;
case NFPROTO_IPV6:
afinfo = &afinfo_ipv6;
break;
case NFPROTO_BRIDGE:
afinfo = &afinfo_bridge;
break;
case NFPROTO_ARP:
afinfo = &afinfo_arp;
break;
default:
fprintf(stderr, "libxtables: unhandled NFPROTO in %s\n",
__func__);
}
}
/**
* xtables_set_params - set the global parameters used by xtables
* @xtp: input xtables_globals structure
*
* The app is expected to pass a valid xtables_globals data-filled
* with proper values
* @xtp cannot be NULL
*
* Returns -1 on failure to set and 0 on success
*/
int xtables_set_params(struct xtables_globals *xtp)
{
if (!xtp) {
fprintf(stderr, "%s: Illegal global params\n",__func__);
return -1;
}
xt_params = xtp;
if (!xt_params->exit_err)
xt_params->exit_err = basic_exit_err;
return 0;
}
int xtables_init_all(struct xtables_globals *xtp, uint8_t nfproto)
{
xtables_init();
xtables_set_nfproto(nfproto);
return xtables_set_params(xtp);
}
/**
* xtables_*alloc - wrappers that exit on failure
*/
void *xtables_calloc(size_t count, size_t size)
{
void *p;
if ((p = calloc(count, size)) == NULL) {
perror("ip[6]tables: calloc failed");
exit(1);
}
return p;
}
void *xtables_malloc(size_t size)
{
void *p;
if ((p = malloc(size)) == NULL) {
perror("ip[6]tables: malloc failed");
exit(1);
}
return p;
}
void *xtables_realloc(void *ptr, size_t size)
{
void *p;
if ((p = realloc(ptr, size)) == NULL) {
perror("ip[6]tables: realloc failed");
exit(1);
}
return p;
}
static char *get_modprobe(void)
{
int procfile;
char *ret;
int count;
procfile = open(PROC_SYS_MODPROBE, O_RDONLY);
if (procfile < 0)
return NULL;
if (fcntl(procfile, F_SETFD, FD_CLOEXEC) == -1) {
fprintf(stderr, "Could not set close on exec: %s\n",
strerror(errno));
exit(1);
}
ret = malloc(PATH_MAX);
if (ret) {
count = read(procfile, ret, PATH_MAX);
if (count > 0 && count < PATH_MAX)
{
if (ret[count - 1] == '\n')
ret[count - 1] = '\0';
else
ret[count] = '\0';
close(procfile);
return ret;
}
}
free(ret);
close(procfile);
return NULL;
}
int xtables_insmod(const char *modname, const char *modprobe, bool quiet)
{
char *buf = NULL;
char *argv[4];
int status;
pid_t pid;
/* If they don't explicitly set it, read out of kernel */
if (!modprobe) {
buf = get_modprobe();
if (!buf)
return -1;
modprobe = buf;
}
argv[0] = (char *)modprobe;
argv[1] = (char *)modname;
argv[2] = quiet ? "-q" : NULL;
argv[3] = NULL;
/*
* Need to flush the buffer, or the child may output it again
* when switching the program thru execv.
*/
fflush(stdout);
if (posix_spawn(&pid, argv[0], NULL, NULL, argv, NULL)) {
free(buf);
return -1;
} else {
waitpid(pid, &status, 0);
}
free(buf);
if (WIFEXITED(status) && WEXITSTATUS(status) == 0)
return 0;
return -1;
}
/* return true if a given file exists within procfs */
static bool proc_file_exists(const char *filename)
{
struct stat s;
struct statfs f;
if (lstat(filename, &s))
return false;
if (!S_ISREG(s.st_mode))
return false;
if (statfs(filename, &f))
return false;
if (f.f_type != PROC_SUPER_MAGIC)
return false;
return true;
}
int xtables_load_ko(const char *modprobe, bool quiet)
{
static bool loaded = false;
int ret;
if (loaded)
return 0;
if (proc_file_exists(afinfo->proc_exists)) {
loaded = true;
return 0;
};
ret = xtables_insmod(afinfo->kmod, modprobe, quiet);
if (ret == 0)
loaded = true;
return ret;
}
/**
* xtables_strtou{i,l} - string to number conversion
* @s: input string
* @end: like strtoul's "end" pointer
* @value: pointer for result
* @min: minimum accepted value
* @max: maximum accepted value
*
* If @end is NULL, we assume the caller wants a "strict strtoul", and hence
* "15a" is rejected.
* In either case, the value obtained is compared for min-max compliance.
* Base is always 0, i.e. autodetect depending on @s.
*
* Returns true/false whether number was accepted. On failure, *value has
* undefined contents.
*/
bool xtables_strtoul(const char *s, char **end, uintmax_t *value,
uintmax_t min, uintmax_t max)
{
uintmax_t v;
const char *p;
char *my_end;
errno = 0;
/* Since strtoul allows leading minus, we have to check for ourself. */
for (p = s; isspace(*p); ++p)
;
if (*p == '-')
return false;
v = strtoumax(s, &my_end, 0);
if (my_end == s)
return false;
if (end != NULL)
*end = my_end;
if (errno != ERANGE && min <= v && (max == 0 || v <= max)) {
if (value != NULL)
*value = v;
if (end == NULL)
return *my_end == '\0';
return true;
}
return false;
}
bool xtables_strtoui(const char *s, char **end, unsigned int *value,
unsigned int min, unsigned int max)
{
uintmax_t v;
bool ret;
ret = xtables_strtoul(s, end, &v, min, max);
if (ret && value != NULL)
*value = v;
return ret;
}
int xtables_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;
}
uint16_t xtables_parse_port(const char *port, const char *proto)
{
unsigned int portnum;
if (xtables_strtoui(port, NULL, &portnum, 0, UINT16_MAX) ||
(portnum = xtables_service_to_port(port, proto)) != (unsigned)-1)
return portnum;
xt_params->exit_err(PARAMETER_PROBLEM,
"invalid port/service `%s' specified", port);
}
void xtables_parse_interface(const char *arg, char *vianame,
unsigned char *mask)
{
unsigned int vialen = strlen(arg);
unsigned int i;
memset(mask, 0, IFNAMSIZ);
memset(vianame, 0, IFNAMSIZ);
if (vialen + 1 > IFNAMSIZ)
xt_params->exit_err(PARAMETER_PROBLEM,
"interface name `%s' must be shorter than IFNAMSIZ"
" (%i)", arg, IFNAMSIZ-1);
strcpy(vianame, arg);
if (vialen == 0)
return;
else if (vianame[vialen - 1] == '+') {
memset(mask, 0xFF, vialen - 1);
/* Don't remove `+' here! -HW */
} else {
/* Include nul-terminator in match */
memset(mask, 0xFF, vialen + 1);
}
/* Display warning on invalid characters */
for (i = 0; vianame[i]; i++) {
if (vianame[i] == '/' || vianame[i] == ' ') {
fprintf(stderr, "Warning: weird character in interface"
" `%s' ('/' and ' ' are not allowed by the kernel).\n",
vianame);
break;
}
}
}
#ifndef NO_SHARED_LIBS
static void *load_extension(const char *search_path, const char *af_prefix,
const char *name, bool is_target)
{
const char *all_prefixes[] = {af_prefix, "libxt_", NULL};
const char **prefix;
const char *dir = search_path, *next;
void *ptr = NULL;
struct stat sb;
char path[256];
do {
next = strchr(dir, ':');
if (next == NULL)
next = dir + strlen(dir);
for (prefix = all_prefixes; *prefix != NULL; ++prefix) {
void *handle;
snprintf(path, sizeof(path), "%.*s/%s%s.so",
(unsigned int)(next - dir), dir,
*prefix, name);
if (stat(path, &sb) != 0) {
if (errno == ENOENT)
continue;
fprintf(stderr, "%s: %s\n", path,
strerror(errno));
return NULL;
}
handle = dlopen(path, RTLD_NOW);
if (handle == NULL) {
fprintf(stderr, "%s: %s\n", path, dlerror());
break;
}
dlreg_add(handle);
if (is_target)
ptr = xtables_find_target(name, XTF_DONT_LOAD);
else
ptr = xtables_find_match(name,
XTF_DONT_LOAD, NULL);
if (ptr != NULL)
return ptr;
errno = ENOENT;
return NULL;
}
dir = next + 1;
} while (*next != '\0');
return NULL;
}
#endif
static bool extension_cmp(const char *name1, const char *name2, uint32_t family)
{
if (strcmp(name1, name2) == 0 &&
(family == afinfo->family ||
family == NFPROTO_UNSPEC))
return true;
return false;
}
struct xtables_match *
xtables_find_match(const char *name, enum xtables_tryload tryload,
struct xtables_rule_match **matches)
{
struct xtables_match *prev = NULL;
struct xtables_match **dptr;
struct xtables_match *ptr;
const char *icmp6 = "icmp6";
if (strlen(name) >= XT_EXTENSION_MAXNAMELEN)
xtables_error(PARAMETER_PROBLEM,
"Invalid match name \"%s\" (%u chars max)",
name, XT_EXTENSION_MAXNAMELEN - 1);
/* This is ugly as hell. Nonetheless, there is no way of changing
* this without hurting backwards compatibility */
if ( (strcmp(name,"icmpv6") == 0) ||
(strcmp(name,"ipv6-icmp") == 0) ||
(strcmp(name,"icmp6") == 0) )
name = icmp6;
/* Trigger delayed initialization */
for (dptr = &xtables_pending_matches; *dptr; ) {
if (extension_cmp(name, (*dptr)->name, (*dptr)->family)) {
ptr = *dptr;
*dptr = (*dptr)->next;
if (xtables_fully_register_pending_match(ptr, prev)) {
prev = ptr;
continue;
} else if (prev) {
continue;
}
*dptr = ptr;
}
dptr = &((*dptr)->next);
}
for (ptr = xtables_matches; ptr; ptr = ptr->next) {
if (extension_cmp(name, ptr->name, ptr->family)) {
struct xtables_match *clone;
/* First match of this type: */
if (ptr->m == NULL)
break;
/* Second and subsequent clones */
clone = xtables_malloc(sizeof(struct xtables_match));
memcpy(clone, ptr, sizeof(struct xtables_match));
clone->udata = NULL;
clone->mflags = 0;
/* This is a clone: */
clone->next = clone;
ptr = clone;
break;
}
}
#ifndef NO_SHARED_LIBS
if (!ptr && tryload != XTF_DONT_LOAD && tryload != XTF_DURING_LOAD) {
ptr = load_extension(xtables_libdir, afinfo->libprefix,
name, false);
if (ptr == NULL && tryload == XTF_LOAD_MUST_SUCCEED)
xt_params->exit_err(PARAMETER_PROBLEM,
"Couldn't load match `%s':%s\n",
name, strerror(errno));
}
#else
if (ptr && !ptr->loaded) {
if (tryload != XTF_DONT_LOAD)
ptr->loaded = 1;
else
ptr = NULL;
}
if(!ptr && (tryload == XTF_LOAD_MUST_SUCCEED)) {
xt_params->exit_err(PARAMETER_PROBLEM,
"Couldn't find match `%s'\n", name);
}
#endif
if (ptr && matches) {
struct xtables_rule_match **i;
struct xtables_rule_match *newentry;
newentry = xtables_malloc(sizeof(struct xtables_rule_match));
for (i = matches; *i; i = &(*i)->next) {
if (extension_cmp(name, (*i)->match->name,
(*i)->match->family))
(*i)->completed = true;
}
newentry->match = ptr;
newentry->completed = false;
newentry->next = NULL;
*i = newentry;
}
return ptr;
}
struct xtables_match *
xtables_find_match_revision(const char *name, enum xtables_tryload tryload,
struct xtables_match *match, int revision)
{
if (!match) {
match = xtables_find_match(name, tryload, NULL);
if (!match)
return NULL;
}
while (1) {
if (match->revision == revision)
return match;
match = match->next;
if (!match)
return NULL;
if (!extension_cmp(name, match->name, match->family))
return NULL;
}
}
struct xtables_target *
xtables_find_target(const char *name, enum xtables_tryload tryload)
{
struct xtables_target *prev = NULL;
struct xtables_target **dptr;
struct xtables_target *ptr;
/* Standard target? */
if (strcmp(name, "") == 0
|| strcmp(name, XTC_LABEL_ACCEPT) == 0
|| strcmp(name, XTC_LABEL_DROP) == 0
|| strcmp(name, XTC_LABEL_QUEUE) == 0
|| strcmp(name, XTC_LABEL_RETURN) == 0)
name = "standard";
/* Trigger delayed initialization */
for (dptr = &xtables_pending_targets; *dptr; ) {
if (extension_cmp(name, (*dptr)->name, (*dptr)->family)) {
ptr = *dptr;
*dptr = (*dptr)->next;
if (xtables_fully_register_pending_target(ptr, prev)) {
prev = ptr;
continue;
} else if (prev) {
continue;
}
*dptr = ptr;
}
dptr = &((*dptr)->next);
}
for (ptr = xtables_targets; ptr; ptr = ptr->next) {
if (extension_cmp(name, ptr->name, ptr->family)) {
#if 0 /* Code block below causes memory leak. (Bugs 162925719 and 168688680) */
struct xtables_target *clone;
/* First target of this type: */
if (ptr->t == NULL)
break;
/* Second and subsequent clones */
clone = xtables_malloc(sizeof(struct xtables_target));
memcpy(clone, ptr, sizeof(struct xtables_target));
clone->udata = NULL;
clone->tflags = 0;
/* This is a clone: */
clone->next = clone;
ptr = clone;
#endif
break;
}
}
#ifndef NO_SHARED_LIBS
if (!ptr && tryload != XTF_DONT_LOAD && tryload != XTF_DURING_LOAD) {
ptr = load_extension(xtables_libdir, afinfo->libprefix,
name, true);
if (ptr == NULL && tryload == XTF_LOAD_MUST_SUCCEED)
xt_params->exit_err(PARAMETER_PROBLEM,
"Couldn't load target `%s':%s\n",
name, strerror(errno));
}
#else
if (ptr && !ptr->loaded) {
if (tryload != XTF_DONT_LOAD)
ptr->loaded = 1;
else
ptr = NULL;
}
if (ptr == NULL && tryload == XTF_LOAD_MUST_SUCCEED) {
xt_params->exit_err(PARAMETER_PROBLEM,
"Couldn't find target `%s'\n", name);
}
#endif
if (ptr)
ptr->used = 1;
return ptr;
}
struct xtables_target *
xtables_find_target_revision(const char *name, enum xtables_tryload tryload,
struct xtables_target *target, int revision)
{
if (!target) {
target = xtables_find_target(name, tryload);
if (!target)
return NULL;
}
while (1) {
if (target->revision == revision)
return target;
target = target->next;
if (!target)
return NULL;
if (!extension_cmp(name, target->name, target->family))
return NULL;
}
}
int xtables_compatible_revision(const char *name, uint8_t revision, int opt)
{
struct xt_get_revision rev;
socklen_t s = sizeof(rev);
int max_rev, sockfd;
sockfd = socket(afinfo->family, SOCK_RAW, IPPROTO_RAW);
if (sockfd < 0) {
if (errno == EPERM) {
/* revision 0 is always supported. */
if (revision != 0)
fprintf(stderr, "%s: Could not determine whether "
"revision %u is supported, "
"assuming it is.\n",
name, revision);
return 1;
}
fprintf(stderr, "Could not open socket to kernel: %s\n",
strerror(errno));
exit(1);
}
if (fcntl(sockfd, F_SETFD, FD_CLOEXEC) == -1) {
fprintf(stderr, "Could not set close on exec: %s\n",
strerror(errno));
exit(1);
}
xtables_load_ko(xtables_modprobe_program, true);
strncpy(rev.name, name, XT_EXTENSION_MAXNAMELEN - 1);
rev.name[XT_EXTENSION_MAXNAMELEN - 1] = '\0';
rev.revision = revision;
max_rev = getsockopt(sockfd, afinfo->ipproto, opt, &rev, &s);
if (max_rev < 0) {
/* Definitely don't support this? */
if (errno == ENOENT || 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 failed strangely: %s\n",
strerror(errno));
exit(1);
}
}
close(sockfd);
return 1;
}
static int compatible_match_revision(const char *name, uint8_t revision)
{
return xt_params->compat_rev(name, revision, afinfo->so_rev_match);
}
static int compatible_target_revision(const char *name, uint8_t revision)
{
return xt_params->compat_rev(name, revision, afinfo->so_rev_target);
}
static void xtables_check_options(const char *name, const struct option *opt)
{
for (; opt->name != NULL; ++opt)
if (opt->val < 0 || opt->val >= XT_OPTION_OFFSET_SCALE) {
fprintf(stderr, "%s: Extension %s uses invalid "
"option value %d\n",xt_params->program_name,
name, opt->val);
exit(1);
}
}
static int xtables_match_prefer(const struct xtables_match *a,
const struct xtables_match *b);
void xtables_register_match(struct xtables_match *me)
{
struct xtables_match **pos;
bool seen_myself = false;
if (me->next) {
fprintf(stderr, "%s: match \"%s\" already registered\n",
xt_params->program_name, me->name);
exit(1);
}
if (me->version == NULL) {
fprintf(stderr, "%s: match %s<%u> is missing a version\n",
xt_params->program_name, me->name, me->revision);
exit(1);
}
if (me->size != XT_ALIGN(me->size)) {
fprintf(stderr, "%s: match \"%s\" has invalid size %u.\n",
xt_params->program_name, me->name,
(unsigned int)me->size);
exit(1);
}
if (strcmp(me->version, XTABLES_VERSION) != 0) {
fprintf(stderr, "%s: match \"%s\" has version \"%s\", "
"but \"%s\" is required.\n",
xt_params->program_name, me->name,
me->version, XTABLES_VERSION);
exit(1);
}
if (strlen(me->name) >= XT_EXTENSION_MAXNAMELEN) {
fprintf(stderr, "%s: match `%s' has invalid name\n",
xt_params->program_name, me->name);
exit(1);
}
if (me->real_name && strlen(me->real_name) >= XT_EXTENSION_MAXNAMELEN) {
fprintf(stderr, "%s: match `%s' has invalid real name\n",
xt_params->program_name, me->real_name);
exit(1);
}
if (me->family >= NPROTO) {
fprintf(stderr,
"%s: BUG: match %s has invalid protocol family\n",
xt_params->program_name, me->name);
exit(1);
}
if (me->x6_options != NULL)
xtables_option_metavalidate(me->name, me->x6_options);
if (me->extra_opts != NULL)
xtables_check_options(me->name, me->extra_opts);
/* order into linked list of matches pending full registration */
for (pos = &xtables_pending_matches; *pos; pos = &(*pos)->next) {
/* group by name and family */
if (strcmp(me->name, (*pos)->name) ||
me->family != (*pos)->family) {
if (seen_myself)
break; /* end of own group, append to it */
continue;
}
/* found own group */
seen_myself = true;
if (xtables_match_prefer(me, *pos) >= 0)
break; /* put preferred items first in group */
}
/* if own group was not found, prepend item */
if (!*pos && !seen_myself)
pos = &xtables_pending_matches;
me->next = *pos;
*pos = me;
#ifdef DEBUG
printf("%s: inserted match %s (family %d, revision %d):\n",
__func__, me->name, me->family, me->revision);
for (pos = &xtables_pending_matches; *pos; pos = &(*pos)->next) {
printf("%s:\tmatch %s (family %d, revision %d)\n", __func__,
(*pos)->name, (*pos)->family, (*pos)->revision);
}
#endif
}
/**
* Compare two actions for their preference
* @a: one action
* @b: another
*
* Like strcmp, returns a negative number if @a is less preferred than @b,
* positive number if @a is more preferred than @b, or zero if equally
* preferred.
*/
static int
xtables_mt_prefer(bool a_alias, unsigned int a_rev, unsigned int a_fam,
bool b_alias, unsigned int b_rev, unsigned int b_fam)
{
/*
* Alias ranks higher than no alias.
* (We want the new action to be used whenever possible.)
*/
if (!a_alias && b_alias)
return -1;
if (a_alias && !b_alias)
return 1;
/* Higher revision ranks higher. */
if (a_rev < b_rev)
return -1;
if (a_rev > b_rev)
return 1;
/* NFPROTO_<specific> ranks higher than NFPROTO_UNSPEC. */
if (a_fam == NFPROTO_UNSPEC && b_fam != NFPROTO_UNSPEC)
return -1;
if (a_fam != NFPROTO_UNSPEC && b_fam == NFPROTO_UNSPEC)
return 1;
/* Must be the same thing. */
return 0;
}
static int xtables_match_prefer(const struct xtables_match *a,
const struct xtables_match *b)
{
return xtables_mt_prefer(a->real_name != NULL,
a->revision, a->family,
b->real_name != NULL,
b->revision, b->family);
}
static int xtables_target_prefer(const struct xtables_target *a,
const struct xtables_target *b)
{
/*
* Note that if x->real_name==NULL, it will be set to x->name in
* xtables_register_*; the direct pointer comparison here is therefore
* legitimate to detect an alias.
*/
return xtables_mt_prefer(a->real_name != NULL,
a->revision, a->family,
b->real_name != NULL,
b->revision, b->family);
}
static bool xtables_fully_register_pending_match(struct xtables_match *me,
struct xtables_match *prev)
{
struct xtables_match **i;
const char *rn;
/* See if new match can be used. */
rn = (me->real_name != NULL) ? me->real_name : me->name;
if (!compatible_match_revision(rn, me->revision))
return false;
if (!prev) {
/* Append to list. */
for (i = &xtables_matches; *i; i = &(*i)->next);
} else {
/* Append it */
i = &prev->next;
prev = prev->next;
}
me->next = prev;
*i = me;
me->m = NULL;
me->mflags = 0;
return true;
}
void xtables_register_matches(struct xtables_match *match, unsigned int n)
{
int i;
for (i = 0; i < n; i++)
xtables_register_match(&match[i]);
}
void xtables_register_target(struct xtables_target *me)
{
struct xtables_target **pos;
bool seen_myself = false;
if (me->next) {
fprintf(stderr, "%s: target \"%s\" already registered\n",
xt_params->program_name, me->name);
exit(1);
}
if (me->version == NULL) {
fprintf(stderr, "%s: target %s<%u> is missing a version\n",
xt_params->program_name, me->name, me->revision);
exit(1);
}
if (me->size != XT_ALIGN(me->size)) {
fprintf(stderr, "%s: target \"%s\" has invalid size %u.\n",
xt_params->program_name, me->name,
(unsigned int)me->size);
exit(1);
}
if (strcmp(me->version, XTABLES_VERSION) != 0) {
fprintf(stderr, "%s: target \"%s\" has version \"%s\", "
"but \"%s\" is required.\n",
xt_params->program_name, me->name,
me->version, XTABLES_VERSION);
exit(1);
}
if (strlen(me->name) >= XT_EXTENSION_MAXNAMELEN) {
fprintf(stderr, "%s: target `%s' has invalid name\n",
xt_params->program_name, me->name);
exit(1);
}
if (me->real_name && strlen(me->real_name) >= XT_EXTENSION_MAXNAMELEN) {
fprintf(stderr, "%s: target `%s' has invalid real name\n",
xt_params->program_name, me->real_name);
exit(1);
}
if (me->family >= NPROTO) {
fprintf(stderr,
"%s: BUG: target %s has invalid protocol family\n",
xt_params->program_name, me->name);
exit(1);
}
if (me->x6_options != NULL)
xtables_option_metavalidate(me->name, me->x6_options);
if (me->extra_opts != NULL)
xtables_check_options(me->name, me->extra_opts);
/* ignore not interested target */
if (me->family != afinfo->family && me->family != AF_UNSPEC)
return;
/* order into linked list of targets pending full registration */
for (pos = &xtables_pending_targets; *pos; pos = &(*pos)->next) {
/* group by name */
if (!extension_cmp(me->name, (*pos)->name, (*pos)->family)) {
if (seen_myself)
break; /* end of own group, append to it */
continue;
}
/* found own group */
seen_myself = true;
if (xtables_target_prefer(me, *pos) >= 0)
break; /* put preferred items first in group */
}
/* if own group was not found, prepend item */
if (!*pos && !seen_myself)
pos = &xtables_pending_targets;
me->next = *pos;
*pos = me;
#ifdef DEBUG
printf("%s: inserted target %s (family %d, revision %d):\n",
__func__, me->name, me->family, me->revision);
for (pos = &xtables_pending_targets; *pos; pos = &(*pos)->next) {
printf("%s:\ttarget %s (family %d, revision %d)\n", __func__,
(*pos)->name, (*pos)->family, (*pos)->revision);
}
#endif
}
static bool xtables_fully_register_pending_target(struct xtables_target *me,
struct xtables_target *prev)
{
struct xtables_target **i;
const char *rn;
if (strcmp(me->name, "standard") != 0) {
/* See if new target can be used. */
rn = (me->real_name != NULL) ? me->real_name : me->name;
if (!compatible_target_revision(rn, me->revision))
return false;
}
if (!prev) {
/* Prepend to list. */
i = &xtables_targets;
prev = xtables_targets;
} else {
/* Append it */
i = &prev->next;
prev = prev->next;
}
me->next = prev;
*i = me;
me->t = NULL;
me->tflags = 0;
return true;
}
void xtables_register_targets(struct xtables_target *target, unsigned int n)
{
int i;
for (i = 0; i < n; i++)
xtables_register_target(&target[i]);
}
/* receives a list of xtables_rule_match, release them */
void xtables_rule_matches_free(struct xtables_rule_match **matches)
{
struct xtables_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;
}
/**
* xtables_param_act - act on condition
* @status: a constant from enum xtables_exittype
*
* %XTF_ONLY_ONCE: print error message that option may only be used once.
* @p1: module name (e.g. "mark")
* @p2(...): option in conflict (e.g. "--mark")
* @p3(...): condition to match on (see extensions/ for examples)
*
* %XTF_NO_INVERT: option does not support inversion
* @p1: module name
* @p2: option in conflict
* @p3: condition to match on
*
* %XTF_BAD_VALUE: bad value for option
* @p1: module name
* @p2: option with which the problem occurred (e.g. "--mark")
* @p3: string the user passed in (e.g. "99999999999999")
*
* %XTF_ONE_ACTION: two mutually exclusive actions have been specified
* @p1: module name
*
* Displays an error message and exits the program.
*/
void xtables_param_act(unsigned int status, const char *p1, ...)
{
const char *p2, *p3;
va_list args;
bool b;
va_start(args, p1);
switch (status) {
case XTF_ONLY_ONCE:
p2 = va_arg(args, const char *);
b = va_arg(args, unsigned int);
if (!b) {
va_end(args);
return;
}
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: \"%s\" option may only be specified once",
p1, p2);
break;
case XTF_NO_INVERT:
p2 = va_arg(args, const char *);
b = va_arg(args, unsigned int);
if (!b) {
va_end(args);
return;
}
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: \"%s\" option cannot be inverted", p1, p2);
break;
case XTF_BAD_VALUE:
p2 = va_arg(args, const char *);
p3 = va_arg(args, const char *);
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: Bad value for \"%s\" option: \"%s\"",
p1, p2, p3);
break;
case XTF_ONE_ACTION:
b = va_arg(args, unsigned int);
if (!b) {
va_end(args);
return;
}
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: At most one action is possible", p1);
break;
default:
xt_params->exit_err(status, p1, args);
break;
}
va_end(args);
}
const char *xtables_ipaddr_to_numeric(const struct in_addr *addrp)
{
static char buf[20];
const unsigned char *bytep = (const void *)&addrp->s_addr;
sprintf(buf, "%u.%u.%u.%u", bytep[0], bytep[1], bytep[2], bytep[3]);
return buf;
}
static const char *ipaddr_to_host(const struct in_addr *addr)
{
static char hostname[NI_MAXHOST];
struct sockaddr_in saddr = {
.sin_family = AF_INET,
.sin_addr = *addr,
};
int err;
err = getnameinfo((const void *)&saddr, sizeof(struct sockaddr_in),
hostname, sizeof(hostname) - 1, NULL, 0, 0);
if (err != 0)
return NULL;
return hostname;
}
static const char *ipaddr_to_network(const struct in_addr *addr)
{
struct netent *net;
if ((net = getnetbyaddr(ntohl(addr->s_addr), AF_INET)) != NULL)
return net->n_name;
return NULL;
}
const char *xtables_ipaddr_to_anyname(const struct in_addr *addr)
{
const char *name;
if ((name = ipaddr_to_host(addr)) != NULL ||
(name = ipaddr_to_network(addr)) != NULL)
return name;
return xtables_ipaddr_to_numeric(addr);
}
int xtables_ipmask_to_cidr(const struct in_addr *mask)
{
uint32_t maskaddr, bits;
int i;
maskaddr = ntohl(mask->s_addr);
/* shortcut for /32 networks */
if (maskaddr == 0xFFFFFFFFL)
return 32;
i = 32;
bits = 0xFFFFFFFEL;
while (--i >= 0 && maskaddr != bits)
bits <<= 1;
if (i >= 0)
return i;
/* this mask cannot be converted to CIDR notation */
return -1;
}
const char *xtables_ipmask_to_numeric(const struct in_addr *mask)
{
static char buf[20];
uint32_t cidr;
cidr = xtables_ipmask_to_cidr(mask);
if (cidr == (unsigned int)-1) {
/* mask was not a decent combination of 1's and 0's */
sprintf(buf, "/%s", xtables_ipaddr_to_numeric(mask));
return buf;
} else if (cidr == 32) {
/* we don't want to see "/32" */
return "";
}
sprintf(buf, "/%d", cidr);
return buf;
}
static struct in_addr *__numeric_to_ipaddr(const char *dotted, bool is_mask)
{
static struct in_addr addr;
unsigned char *addrp;
unsigned int onebyte;
char buf[20], *p, *q;
int i;
/* copy dotted string, because we need to modify it */
strncpy(buf, dotted, sizeof(buf) - 1);
buf[sizeof(buf) - 1] = '\0';
addrp = (void *)&addr.s_addr;
p = buf;
for (i = 0; i < 3; ++i) {
if ((q = strchr(p, '.')) == NULL) {
if (is_mask)
return NULL;
/* autocomplete, this is a network address */
if (!xtables_strtoui(p, NULL, &onebyte, 0, UINT8_MAX))
return NULL;
addrp[i] = onebyte;
while (i < 3)
addrp[++i] = 0;
return &addr;
}
*q = '\0';
if (!xtables_strtoui(p, NULL, &onebyte, 0, UINT8_MAX))
return NULL;
addrp[i] = onebyte;
p = q + 1;
}
/* we have checked 3 bytes, now we check the last one */
if (!xtables_strtoui(p, NULL, &onebyte, 0, UINT8_MAX))
return NULL;
addrp[3] = onebyte;
return &addr;
}
struct in_addr *xtables_numeric_to_ipaddr(const char *dotted)
{
return __numeric_to_ipaddr(dotted, false);
}
struct in_addr *xtables_numeric_to_ipmask(const char *dotted)
{
return __numeric_to_ipaddr(dotted, true);
}
static struct in_addr *network_to_ipaddr(const char *name)
{
static struct in_addr addr;
struct netent *net;
if ((net = getnetbyname(name)) != NULL) {
if (net->n_addrtype != AF_INET)
return NULL;
addr.s_addr = htonl(net->n_net);
return &addr;
}
return NULL;
}
static struct in_addr *host_to_ipaddr(const char *name, unsigned int *naddr)
{
struct in_addr *addr;
struct addrinfo hints;
struct addrinfo *res, *p;
int err;
unsigned int i;
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_INET;
hints.ai_socktype = SOCK_RAW;
*naddr = 0;
err = getaddrinfo(name, NULL, &hints, &res);
if (err != 0)
return NULL;
for (p = res; p != NULL; p = p->ai_next)
++*naddr;
addr = xtables_calloc(*naddr, sizeof(struct in_addr));
for (i = 0, p = res; p != NULL; p = p->ai_next)
memcpy(&addr[i++],
&((const struct sockaddr_in *)p->ai_addr)->sin_addr,
sizeof(struct in_addr));
freeaddrinfo(res);
return addr;
}
static struct in_addr *
ipparse_hostnetwork(const char *name, unsigned int *naddrs)
{
struct in_addr *addrptmp, *addrp;
if ((addrptmp = xtables_numeric_to_ipaddr(name)) != NULL ||
(addrptmp = network_to_ipaddr(name)) != NULL) {
addrp = xtables_malloc(sizeof(struct in_addr));
memcpy(addrp, addrptmp, sizeof(*addrp));
*naddrs = 1;
return addrp;
}
if ((addrptmp = host_to_ipaddr(name, naddrs)) != NULL)
return addrptmp;
xt_params->exit_err(PARAMETER_PROBLEM, "host/network `%s' not found", name);
}
static struct in_addr *parse_ipmask(const 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 = xtables_numeric_to_ipmask(mask)) != NULL)
/* dotted_to_addr already returns a network byte order addr */
return addrp;
if (!xtables_strtoui(mask, NULL, &bits, 0, 32))
xt_params->exit_err(PARAMETER_PROBLEM,
"invalid mask `%s' specified", mask);
if (bits != 0) {
maskaddr.s_addr = htonl(0xFFFFFFFF << (32 - bits));
return &maskaddr;
}
maskaddr.s_addr = 0U;
return &maskaddr;
}
void xtables_ipparse_multiple(const char *name, struct in_addr **addrpp,
struct in_addr **maskpp, unsigned int *naddrs)
{
struct in_addr *addrp;
char buf[256], *p, *next;
unsigned int len, i, j, n, count = 1;
const char *loop = name;
while ((loop = strchr(loop, ',')) != NULL) {
++count;
++loop; /* skip ',' */
}
*addrpp = xtables_malloc(sizeof(struct in_addr) * count);
*maskpp = xtables_malloc(sizeof(struct in_addr) * count);
loop = name;
for (i = 0; i < count; ++i) {
while (isspace(*loop))
++loop;
next = strchr(loop, ',');
if (next != NULL)
len = next - loop;
else
len = strlen(loop);
if (len > sizeof(buf) - 1)
xt_params->exit_err(PARAMETER_PROBLEM,
"Hostname too long");
strncpy(buf, loop, len);
buf[len] = '\0';
if ((p = strrchr(buf, '/')) != NULL) {
*p = '\0';
addrp = parse_ipmask(p + 1);
} else {
addrp = parse_ipmask(NULL);
}
memcpy(*maskpp + i, addrp, sizeof(*addrp));
/* if a null mask is given, the name is ignored, like in "any/0" */
if ((*maskpp + i)->s_addr == 0)
/*
* A bit pointless to process multiple addresses
* in this case...
*/
strcpy(buf, "0.0.0.0");
addrp = ipparse_hostnetwork(buf, &n);
if (n > 1) {
count += n - 1;
*addrpp = xtables_realloc(*addrpp,
sizeof(struct in_addr) * count);
*maskpp = xtables_realloc(*maskpp,
sizeof(struct in_addr) * count);
for (j = 0; j < n; ++j)
/* for each new addr */
memcpy(*addrpp + i + j, addrp + j,
sizeof(*addrp));
for (j = 1; j < n; ++j)
/* for each new mask */
memcpy(*maskpp + i + j, *maskpp + i,
sizeof(*addrp));
i += n - 1;
} else {
memcpy(*addrpp + i, addrp, sizeof(*addrp));
}
/* free what ipparse_hostnetwork had allocated: */
free(addrp);
if (next == NULL)
break;
loop = next + 1;
}
*naddrs = count;
for (i = 0; i < count; ++i)
(*addrpp+i)->s_addr &= (*maskpp+i)->s_addr;
}
/**
* xtables_ipparse_any - transform arbitrary name to in_addr
*
* Possible inputs (pseudo regex):
* m{^($hostname|$networkname|$ipaddr)(/$mask)?}
* "1.2.3.4/5", "1.2.3.4", "hostname", "networkname"
*/
void xtables_ipparse_any(const char *name, struct in_addr **addrpp,
struct in_addr *maskp, unsigned int *naddrs)
{
unsigned int i, j, k, n;
struct in_addr *addrp;
char buf[256], *p;
strncpy(buf, name, sizeof(buf) - 1);
buf[sizeof(buf) - 1] = '\0';
if ((p = strrchr(buf, '/')) != NULL) {
*p = '\0';
addrp = parse_ipmask(p + 1);
} else {
addrp = parse_ipmask(NULL);
}
memcpy(maskp, addrp, sizeof(*maskp));
/* if a null mask is given, the name is ignored, like in "any/0" */
if (maskp->s_addr == 0U)
strcpy(buf, "0.0.0.0");
addrp = *addrpp = ipparse_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) {
/*
* Nuke the dup by copying an address from the
* tail here, and check the current position
* again (--j).
*/
memcpy(&addrp[--j], &addrp[--*naddrs],
sizeof(struct in_addr));
break;
}
}
}
const char *xtables_ip6addr_to_numeric(const struct in6_addr *addrp)
{
/* 0000:0000:0000:0000:0000:0000:000.000.000.000
* 0000:0000:0000:0000:0000:0000:0000:0000 */
static char buf[50+1];
return inet_ntop(AF_INET6, addrp, buf, sizeof(buf));
}
static const char *ip6addr_to_host(const struct in6_addr *addr)
{
static char hostname[NI_MAXHOST];
struct sockaddr_in6 saddr;
int err;
memset(&saddr, 0, sizeof(struct sockaddr_in6));
memcpy(&saddr.sin6_addr, addr, sizeof(*addr));
saddr.sin6_family = AF_INET6;
err = getnameinfo((const void *)&saddr, sizeof(struct sockaddr_in6),
hostname, sizeof(hostname) - 1, NULL, 0, 0);
if (err != 0)
return NULL;
return hostname;
}
const char *xtables_ip6addr_to_anyname(const struct in6_addr *addr)
{
const char *name;
if ((name = ip6addr_to_host(addr)) != NULL)
return name;
return xtables_ip6addr_to_numeric(addr);
}
int xtables_ip6mask_to_cidr(const struct in6_addr *k)
{
unsigned int bits = 0;
uint32_t a, b, c, d;
a = ntohl(k->s6_addr32[0]);
b = ntohl(k->s6_addr32[1]);
c = ntohl(k->s6_addr32[2]);
d = ntohl(k->s6_addr32[3]);
while (a & 0x80000000U) {
++bits;
a <<= 1;
a |= (b >> 31) & 1;
b <<= 1;
b |= (c >> 31) & 1;
c <<= 1;
c |= (d >> 31) & 1;
d <<= 1;
}
if (a != 0 || b != 0 || c != 0 || d != 0)
return -1;
return bits;
}
const char *xtables_ip6mask_to_numeric(const struct in6_addr *addrp)
{
static char buf[50+2];
int l = xtables_ip6mask_to_cidr(addrp);
if (l == -1) {
strcpy(buf, "/");
strcat(buf, xtables_ip6addr_to_numeric(addrp));
return buf;
}
/* we don't want to see "/128" */
if (l == 128)
return "";
else
sprintf(buf, "/%d", l);
return buf;
}
struct in6_addr *xtables_numeric_to_ip6addr(const char *num)
{
static struct in6_addr ap;
int err;
if ((err = inet_pton(AF_INET6, num, &ap)) == 1)
return &ap;
return NULL;
}
static struct in6_addr *
host_to_ip6addr(const char *name, unsigned int *naddr)
{
struct in6_addr *addr;
struct addrinfo hints;
struct addrinfo *res, *p;
int err;
unsigned int i;
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_INET6;
hints.ai_socktype = SOCK_RAW;
*naddr = 0;
err = getaddrinfo(name, NULL, &hints, &res);
if (err != 0)
return NULL;
/* Find length of address chain */
for (p = res; p != NULL; p = p->ai_next)
++*naddr;
/* Copy each element of the address chain */
addr = xtables_calloc(*naddr, sizeof(struct in6_addr));
for (i = 0, p = res; p != NULL; p = p->ai_next)
memcpy(&addr[i++],
&((const struct sockaddr_in6 *)p->ai_addr)->sin6_addr,
sizeof(struct in6_addr));
freeaddrinfo(res);
return addr;
}
static struct in6_addr *network_to_ip6addr(const char *name)
{
/* abort();*/
/* TODO: not implemented yet, but the exception breaks the
* name resolvation */
return NULL;
}
static struct in6_addr *
ip6parse_hostnetwork(const char *name, unsigned int *naddrs)
{
struct in6_addr *addrp, *addrptmp;
if ((addrptmp = xtables_numeric_to_ip6addr(name)) != NULL ||
(addrptmp = network_to_ip6addr(name)) != NULL) {
addrp = xtables_malloc(sizeof(struct in6_addr));
memcpy(addrp, addrptmp, sizeof(*addrp));
*naddrs = 1;
return addrp;
}
if ((addrp = host_to_ip6addr(name, naddrs)) != NULL)
return addrp;
xt_params->exit_err(PARAMETER_PROBLEM, "host/network `%s' not found", name);
}
static struct in6_addr *parse_ip6mask(char *mask)
{
static struct in6_addr maskaddr;
struct in6_addr *addrp;
unsigned int bits;
if (mask == NULL) {
/* no mask at all defaults to 128 bits */
memset(&maskaddr, 0xff, sizeof maskaddr);
return &maskaddr;
}
if ((addrp = xtables_numeric_to_ip6addr(mask)) != NULL)
return addrp;
if (!xtables_strtoui(mask, NULL, &bits, 0, 128))
xt_params->exit_err(PARAMETER_PROBLEM,
"invalid mask `%s' specified", mask);
if (bits != 0) {
char *p = (void *)&maskaddr;
memset(p, 0xff, bits / 8);
memset(p + ((bits + 7) / 8), 0, (128 - bits) / 8);
if (bits < 128)
p[bits/8] = 0xff << (8 - (bits & 7));
return &maskaddr;
}
memset(&maskaddr, 0, sizeof(maskaddr));
return &maskaddr;
}
void
xtables_ip6parse_multiple(const char *name, struct in6_addr **addrpp,
struct in6_addr **maskpp, unsigned int *naddrs)
{
static const struct in6_addr zero_addr;
struct in6_addr *addrp;
char buf[256], *p, *next;
unsigned int len, i, j, n, count = 1;
const char *loop = name;
while ((loop = strchr(loop, ',')) != NULL) {
++count;
++loop; /* skip ',' */
}
*addrpp = xtables_malloc(sizeof(struct in6_addr) * count);
*maskpp = xtables_malloc(sizeof(struct in6_addr) * count);
loop = name;
for (i = 0; i < count /*NB: count can grow*/; ++i) {
while (isspace(*loop))
++loop;
next = strchr(loop, ',');
if (next != NULL)
len = next - loop;
else
len = strlen(loop);
if (len > sizeof(buf) - 1)
xt_params->exit_err(PARAMETER_PROBLEM,
"Hostname too long");
strncpy(buf, loop, len);
buf[len] = '\0';
if ((p = strrchr(buf, '/')) != NULL) {
*p = '\0';
addrp = parse_ip6mask(p + 1);
} else {
addrp = parse_ip6mask(NULL);
}
memcpy(*maskpp + i, addrp, sizeof(*addrp));
/* if a null mask is given, the name is ignored, like in "any/0" */
if (memcmp(*maskpp + i, &zero_addr, sizeof(zero_addr)) == 0)
strcpy(buf, "::");
addrp = ip6parse_hostnetwork(buf, &n);
if (n > 1) {
count += n - 1;
*addrpp = xtables_realloc(*addrpp,
sizeof(struct in6_addr) * count);
*maskpp = xtables_realloc(*maskpp,
sizeof(struct in6_addr) * count);
for (j = 0; j < n; ++j)
/* for each new addr */
memcpy(*addrpp + i + j, addrp + j,
sizeof(*addrp));
for (j = 1; j < n; ++j)
/* for each new mask */
memcpy(*maskpp + i + j, *maskpp + i,
sizeof(*addrp));
i += n - 1;
} else {
memcpy(*addrpp + i, addrp, sizeof(*addrp));
}
/* free what ip6parse_hostnetwork had allocated: */
free(addrp);
if (next == NULL)
break;
loop = next + 1;
}
*naddrs = count;
for (i = 0; i < count; ++i)
for (j = 0; j < 4; ++j)
(*addrpp+i)->s6_addr32[j] &= (*maskpp+i)->s6_addr32[j];
}
void xtables_ip6parse_any(const char *name, struct in6_addr **addrpp,
struct in6_addr *maskp, unsigned int *naddrs)
{
static const struct in6_addr zero_addr;
struct in6_addr *addrp;
unsigned int i, j, k, n;
char buf[256], *p;
strncpy(buf, name, sizeof(buf) - 1);
buf[sizeof(buf)-1] = '\0';
if ((p = strrchr(buf, '/')) != NULL) {
*p = '\0';
addrp = parse_ip6mask(p + 1);
} else {
addrp = parse_ip6mask(NULL);
}
memcpy(maskp, addrp, sizeof(*maskp));
/* if a null mask is given, the name is ignored, like in "any/0" */
if (memcmp(maskp, &zero_addr, sizeof(zero_addr)) == 0)
strcpy(buf, "::");
addrp = *addrpp = ip6parse_hostnetwork(buf, naddrs);
n = *naddrs;
for (i = 0, j = 0; i < n; ++i) {
for (k = 0; k < 4; ++k)
addrp[j].s6_addr32[k] &= maskp->s6_addr32[k];
++j;
for (k = 0; k < j - 1; ++k)
if (IN6_ARE_ADDR_EQUAL(&addrp[k], &addrp[j - 1])) {
/*
* Nuke the dup by copying an address from the
* tail here, and check the current position
* again (--j).
*/
memcpy(&addrp[--j], &addrp[--*naddrs],
sizeof(struct in_addr));
break;
}
}
}
void xtables_save_string(const char *value)
{
static const char no_quote_chars[] = "_-0123456789"
"abcdefghijklmnopqrstuvwxyz"
"ABCDEFGHIJKLMNOPQRSTUVWXYZ";
static const char escape_chars[] = "\"\\'";
size_t length;
const char *p;
length = strspn(value, no_quote_chars);
if (length > 0 && value[length] == 0) {
/* no quoting required */
putchar(' ');
fputs(value, stdout);
} else {
/* there is at least one dangerous character in the
value, which we have to quote. Write double quotes
around the value and escape special characters with
a backslash */
printf(" \"");
for (p = strpbrk(value, escape_chars); p != NULL;
p = strpbrk(value, escape_chars)) {
if (p > value)
fwrite(value, 1, p - value, stdout);
putchar('\\');
putchar(*p);
value = p + 1;
}
/* print the rest and finish the double quoted
string */
fputs(value, stdout);
putchar('\"');
}
}
const struct xtables_pprot xtables_chain_protos[] = {
{"tcp", IPPROTO_TCP},
{"sctp", IPPROTO_SCTP},
{"udp", IPPROTO_UDP},
{"udplite", IPPROTO_UDPLITE},
{"icmp", IPPROTO_ICMP},
{"icmpv6", IPPROTO_ICMPV6},
{"ipv6-icmp", IPPROTO_ICMPV6},
{"esp", IPPROTO_ESP},
{"ah", IPPROTO_AH},
{"ipv6-mh", IPPROTO_MH},
{"mh", IPPROTO_MH},
{"all", 0},
{NULL},
};
uint16_t
xtables_parse_protocol(const char *s)
{
const struct protoent *pent;
unsigned int proto, i;
if (xtables_strtoui(s, NULL, &proto, 0, UINT8_MAX))
return proto;
/* 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") == 0)
return 0;
pent = getprotobyname(s);
if (pent != NULL)
return pent->p_proto;
for (i = 0; i < ARRAY_SIZE(xtables_chain_protos); ++i) {
if (xtables_chain_protos[i].name == NULL)
continue;
if (strcmp(s, xtables_chain_protos[i].name) == 0)
return xtables_chain_protos[i].num;
}
xt_params->exit_err(PARAMETER_PROBLEM,
"unknown protocol \"%s\" specified", s);
return -1;
}
void xtables_print_num(uint64_t number, unsigned int format)
{
if (!(format & FMT_KILOMEGAGIGA)) {
printf(FMT("%8llu ","%llu "), (unsigned long long)number);
return;
}
if (number <= 99999) {
printf(FMT("%5llu ","%llu "), (unsigned long long)number);
return;
}
number = (number + 500) / 1000;
if (number <= 9999) {
printf(FMT("%4lluK ","%lluK "), (unsigned long long)number);
return;
}
number = (number + 500) / 1000;
if (number <= 9999) {
printf(FMT("%4lluM ","%lluM "), (unsigned long long)number);
return;
}
number = (number + 500) / 1000;
if (number <= 9999) {
printf(FMT("%4lluG ","%lluG "), (unsigned long long)number);
return;
}
number = (number + 500) / 1000;
printf(FMT("%4lluT ","%lluT "), (unsigned long long)number);
}
#include <netinet/ether.h>
static const unsigned char mac_type_unicast[ETH_ALEN] = {};
static const unsigned char msk_type_unicast[ETH_ALEN] = {1};
static const unsigned char mac_type_multicast[ETH_ALEN] = {1};
static const unsigned char msk_type_multicast[ETH_ALEN] = {1};
#define ALL_ONE_MAC {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}
static const unsigned char mac_type_broadcast[ETH_ALEN] = ALL_ONE_MAC;
static const unsigned char msk_type_broadcast[ETH_ALEN] = ALL_ONE_MAC;
static const unsigned char mac_type_bridge_group[ETH_ALEN] = {0x01, 0x80, 0xc2};
static const unsigned char msk_type_bridge_group[ETH_ALEN] = ALL_ONE_MAC;
#undef ALL_ONE_MAC
int xtables_parse_mac_and_mask(const char *from, void *to, void *mask)
{
char *p;
int i;
struct ether_addr *addr = NULL;
if (strcasecmp(from, "Unicast") == 0) {
memcpy(to, mac_type_unicast, ETH_ALEN);
memcpy(mask, msk_type_unicast, ETH_ALEN);
return 0;
}
if (strcasecmp(from, "Multicast") == 0) {
memcpy(to, mac_type_multicast, ETH_ALEN);
memcpy(mask, msk_type_multicast, ETH_ALEN);
return 0;
}
if (strcasecmp(from, "Broadcast") == 0) {
memcpy(to, mac_type_broadcast, ETH_ALEN);
memcpy(mask, msk_type_broadcast, ETH_ALEN);
return 0;
}
if (strcasecmp(from, "BGA") == 0) {
memcpy(to, mac_type_bridge_group, ETH_ALEN);
memcpy(mask, msk_type_bridge_group, ETH_ALEN);
return 0;
}
if ( (p = strrchr(from, '/')) != NULL) {
*p = '\0';
if (!(addr = ether_aton(p + 1)))
return -1;
memcpy(mask, addr, ETH_ALEN);
} else
memset(mask, 0xff, ETH_ALEN);
if (!(addr = ether_aton(from)))
return -1;
memcpy(to, addr, ETH_ALEN);
for (i = 0; i < ETH_ALEN; i++)
((char *)to)[i] &= ((char *)mask)[i];
return 0;
}
int xtables_print_well_known_mac_and_mask(const void *mac, const void *mask)
{
if (!memcmp(mac, mac_type_unicast, ETH_ALEN) &&
!memcmp(mask, msk_type_unicast, ETH_ALEN))
printf("Unicast");
else if (!memcmp(mac, mac_type_multicast, ETH_ALEN) &&
!memcmp(mask, msk_type_multicast, ETH_ALEN))
printf("Multicast");
else if (!memcmp(mac, mac_type_broadcast, ETH_ALEN) &&
!memcmp(mask, msk_type_broadcast, ETH_ALEN))
printf("Broadcast");
else if (!memcmp(mac, mac_type_bridge_group, ETH_ALEN) &&
!memcmp(mask, msk_type_bridge_group, ETH_ALEN))
printf("BGA");
else
return -1;
return 0;
}
void xtables_print_mac(const unsigned char *macaddress)
{
unsigned int i;
printf("%02x", macaddress[0]);
for (i = 1; i < 6; ++i)
printf(":%02x", macaddress[i]);
}
void xtables_print_mac_and_mask(const unsigned char *mac, const unsigned char *mask)
{
static const char hlpmsk[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
xtables_print_mac(mac);
if (memcmp(mask, hlpmsk, 6) == 0)
return;
printf("/");
xtables_print_mac(mask);
}
void xtables_parse_val_mask(struct xt_option_call *cb,
unsigned int *val, unsigned int *mask,
const struct xtables_lmap *lmap)
{
char *end;
*mask = ~0U;
if (!xtables_strtoui(cb->arg, &end, val, 0, UINT32_MAX)) {
if (lmap)
goto name2val;
else
goto bad_val;
}
if (*end == '\0')
return;
if (*end != '/') {
if (lmap)
goto name2val;
else
goto garbage;
}
if (!xtables_strtoui(end + 1, &end, mask, 0, UINT32_MAX))
goto bad_val;
if (*end == '\0')
return;
garbage:
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: trailing garbage after value "
"for option \"--%s\".\n",
cb->ext_name, cb->entry->name);
bad_val:
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: bad integer value for option \"--%s\", "
"or out of range.\n",
cb->ext_name, cb->entry->name);
name2val:
*val = xtables_lmap_name2id(lmap, cb->arg);
if ((int)*val == -1)
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: could not map name %s to an integer value "
"for option \"--%s\".\n",
cb->ext_name, cb->arg, cb->entry->name);
}
void xtables_print_val_mask(unsigned int val, unsigned int mask,
const struct xtables_lmap *lmap)
{
if (mask != ~0U) {
printf(" 0x%x/0x%x", val, mask);
return;
}
if (lmap) {
const char *name = xtables_lmap_id2name(lmap, val);
if (name) {
printf(" %s", name);
return;
}
}
printf(" 0x%x", val);
}
int kernel_version;
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");
xtables_free_opts(1);
exit(1);
}
sscanf(uts.release, "%d.%d.%d", &x, &y, &z);
kernel_version = LINUX_VERSION(x, y, z);
}
#include <linux/netfilter/nf_tables.h>
struct xt_xlate {
struct {
char *data;
int size;
int rem;
int off;
} buf;
char comment[NFT_USERDATA_MAXLEN];
};
struct xt_xlate *xt_xlate_alloc(int size)
{
struct xt_xlate *xl;
xl = malloc(sizeof(struct xt_xlate));
if (xl == NULL)
xtables_error(RESOURCE_PROBLEM, "OOM");
xl->buf.data = malloc(size);
if (xl->buf.data == NULL)
xtables_error(RESOURCE_PROBLEM, "OOM");
xl->buf.data[0] = '\0';
xl->buf.size = size;
xl->buf.rem = size;
xl->buf.off = 0;
xl->comment[0] = '\0';
return xl;
}
void xt_xlate_free(struct xt_xlate *xl)
{
free(xl->buf.data);
free(xl);
}
void xt_xlate_add(struct xt_xlate *xl, const char *fmt, ...)
{
va_list ap;
int len;
va_start(ap, fmt);
len = vsnprintf(xl->buf.data + xl->buf.off, xl->buf.rem, fmt, ap);
if (len < 0 || len >= xl->buf.rem)
xtables_error(RESOURCE_PROBLEM, "OOM");
va_end(ap);
xl->buf.rem -= len;
xl->buf.off += len;
}
void xt_xlate_add_comment(struct xt_xlate *xl, const char *comment)
{
strncpy(xl->comment, comment, NFT_USERDATA_MAXLEN - 1);
xl->comment[NFT_USERDATA_MAXLEN - 1] = '\0';
}
const char *xt_xlate_get_comment(struct xt_xlate *xl)
{
return xl->comment[0] ? xl->comment : NULL;
}
const char *xt_xlate_get(struct xt_xlate *xl)
{
return xl->buf.data;
}