/*
* (C) 2012 by Pablo Neira Ayuso <pablo@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 code has been sponsored by Sophos Astaro <http://www.sophos.com>
*/
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <stdbool.h>
#include <errno.h>
#include <netdb.h> /* getprotobynumber */
#include <time.h>
#include <stdarg.h>
#include <inttypes.h>
#include <assert.h>
#include <xtables.h>
#include <libiptc/libxtc.h>
#include <libiptc/xtcshared.h>
#include <stdlib.h>
#include <string.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <netinet/ip6.h>
#include <linux/netlink.h>
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nf_tables.h>
#include <linux/netfilter/nf_tables_compat.h>
#include <linux/netfilter/xt_limit.h>
#include <libmnl/libmnl.h>
#include <libnftnl/table.h>
#include <libnftnl/chain.h>
#include <libnftnl/rule.h>
#include <libnftnl/expr.h>
#include <libnftnl/set.h>
#include <libnftnl/udata.h>
#include <libnftnl/batch.h>
#include <netinet/in.h> /* inet_ntoa */
#include <arpa/inet.h>
#include "nft.h"
#include "xshared.h" /* proto_to_name */
#include "nft-shared.h"
#include "xtables-config-parser.h"
static void *nft_fn;
int mnl_talk(struct nft_handle *h, struct nlmsghdr *nlh,
int (*cb)(const struct nlmsghdr *nlh, void *data),
void *data)
{
int ret;
char buf[16536];
if (mnl_socket_sendto(h->nl, nlh, nlh->nlmsg_len) < 0)
return -1;
ret = mnl_socket_recvfrom(h->nl, buf, sizeof(buf));
while (ret > 0) {
ret = mnl_cb_run(buf, ret, h->seq, h->portid, cb, data);
if (ret <= 0)
break;
ret = mnl_socket_recvfrom(h->nl, buf, sizeof(buf));
}
if (ret == -1) {
return -1;
}
return 0;
}
#define NFT_NLMSG_MAXSIZE (UINT16_MAX + getpagesize())
/* selected batch page is 256 Kbytes long to load ruleset of
* half a million rules without hitting -EMSGSIZE due to large
* iovec.
*/
#define BATCH_PAGE_SIZE getpagesize() * 32
static struct nftnl_batch *mnl_batch_init(void)
{
struct nftnl_batch *batch;
batch = nftnl_batch_alloc(BATCH_PAGE_SIZE, NFT_NLMSG_MAXSIZE);
if (batch == NULL)
return NULL;
return batch;
}
static void mnl_nft_batch_continue(struct nftnl_batch *batch)
{
assert(nftnl_batch_update(batch) >= 0);
}
static uint32_t mnl_batch_begin(struct nftnl_batch *batch, uint32_t seqnum)
{
nftnl_batch_begin(nftnl_batch_buffer(batch), seqnum);
mnl_nft_batch_continue(batch);
return seqnum;
}
static void mnl_batch_end(struct nftnl_batch *batch, uint32_t seqnum)
{
nftnl_batch_end(nftnl_batch_buffer(batch), seqnum);
mnl_nft_batch_continue(batch);
}
static void mnl_batch_reset(struct nftnl_batch *batch)
{
nftnl_batch_free(batch);
}
struct mnl_err {
struct list_head head;
int err;
uint32_t seqnum;
};
static void mnl_err_list_node_add(struct list_head *err_list, int error,
int seqnum)
{
struct mnl_err *err = malloc(sizeof(struct mnl_err));
err->seqnum = seqnum;
err->err = error;
list_add_tail(&err->head, err_list);
}
static void mnl_err_list_free(struct mnl_err *err)
{
list_del(&err->head);
free(err);
}
static int nlbuffsiz;
static void mnl_set_sndbuffer(const struct mnl_socket *nl,
struct nftnl_batch *batch)
{
int newbuffsiz;
if (nftnl_batch_iovec_len(batch) * BATCH_PAGE_SIZE <= nlbuffsiz)
return;
newbuffsiz = nftnl_batch_iovec_len(batch) * BATCH_PAGE_SIZE;
/* Rise sender buffer length to avoid hitting -EMSGSIZE */
if (setsockopt(mnl_socket_get_fd(nl), SOL_SOCKET, SO_SNDBUFFORCE,
&newbuffsiz, sizeof(socklen_t)) < 0)
return;
nlbuffsiz = newbuffsiz;
}
static ssize_t mnl_nft_socket_sendmsg(const struct mnl_socket *nf_sock,
struct nftnl_batch *batch)
{
static const struct sockaddr_nl snl = {
.nl_family = AF_NETLINK
};
uint32_t iov_len = nftnl_batch_iovec_len(batch);
struct iovec iov[iov_len];
struct msghdr msg = {
.msg_name = (struct sockaddr *) &snl,
.msg_namelen = sizeof(snl),
.msg_iov = iov,
.msg_iovlen = iov_len,
};
mnl_set_sndbuffer(nf_sock, batch);
nftnl_batch_iovec(batch, iov, iov_len);
return sendmsg(mnl_socket_get_fd(nf_sock), &msg, 0);
}
static int mnl_batch_talk(const struct mnl_socket *nf_sock,
struct nftnl_batch *batch, struct list_head *err_list)
{
const struct mnl_socket *nl = nf_sock;
int ret, fd = mnl_socket_get_fd(nl), portid = mnl_socket_get_portid(nl);
char rcv_buf[MNL_SOCKET_BUFFER_SIZE];
fd_set readfds;
struct timeval tv = {
.tv_sec = 0,
.tv_usec = 0
};
int err = 0;
ret = mnl_nft_socket_sendmsg(nf_sock, batch);
if (ret == -1)
return -1;
FD_ZERO(&readfds);
FD_SET(fd, &readfds);
/* receive and digest all the acknowledgments from the kernel. */
ret = select(fd+1, &readfds, NULL, NULL, &tv);
if (ret == -1)
return -1;
while (ret > 0 && FD_ISSET(fd, &readfds)) {
struct nlmsghdr *nlh = (struct nlmsghdr *)rcv_buf;
ret = mnl_socket_recvfrom(nl, rcv_buf, sizeof(rcv_buf));
if (ret == -1)
return -1;
ret = mnl_cb_run(rcv_buf, ret, 0, portid, NULL, NULL);
/* Continue on error, make sure we get all acknowledgments */
if (ret == -1) {
mnl_err_list_node_add(err_list, errno, nlh->nlmsg_seq);
err = -1;
}
ret = select(fd+1, &readfds, NULL, NULL, &tv);
if (ret == -1)
return -1;
FD_ZERO(&readfds);
FD_SET(fd, &readfds);
}
return err;
}
enum obj_update_type {
NFT_COMPAT_TABLE_ADD,
NFT_COMPAT_TABLE_FLUSH,
NFT_COMPAT_CHAIN_ADD,
NFT_COMPAT_CHAIN_USER_ADD,
NFT_COMPAT_CHAIN_USER_DEL,
NFT_COMPAT_CHAIN_USER_FLUSH,
NFT_COMPAT_CHAIN_UPDATE,
NFT_COMPAT_CHAIN_RENAME,
NFT_COMPAT_CHAIN_ZERO,
NFT_COMPAT_RULE_APPEND,
NFT_COMPAT_RULE_INSERT,
NFT_COMPAT_RULE_REPLACE,
NFT_COMPAT_RULE_DELETE,
NFT_COMPAT_RULE_FLUSH,
};
enum obj_action {
NFT_COMPAT_COMMIT,
NFT_COMPAT_ABORT,
};
struct obj_update {
struct list_head head;
enum obj_update_type type;
unsigned int seq;
union {
struct nftnl_table *table;
struct nftnl_chain *chain;
struct nftnl_rule *rule;
void *ptr;
};
struct {
unsigned int lineno;
} error;
};
static int mnl_append_error(const struct nft_handle *h,
const struct obj_update *o,
const struct mnl_err *err,
char *buf, unsigned int len)
{
static const char *type_name[] = {
[NFT_COMPAT_TABLE_ADD] = "TABLE_ADD",
[NFT_COMPAT_TABLE_FLUSH] = "TABLE_FLUSH",
[NFT_COMPAT_CHAIN_ADD] = "CHAIN_ADD",
[NFT_COMPAT_CHAIN_USER_ADD] = "CHAIN_USER_ADD",
[NFT_COMPAT_CHAIN_USER_DEL] = "CHAIN_USER_DEL",
[NFT_COMPAT_CHAIN_USER_FLUSH] = "CHAIN_USER_FLUSH",
[NFT_COMPAT_CHAIN_UPDATE] = "CHAIN_UPDATE",
[NFT_COMPAT_CHAIN_RENAME] = "CHAIN_RENAME",
[NFT_COMPAT_CHAIN_ZERO] = "CHAIN_ZERO",
[NFT_COMPAT_RULE_APPEND] = "RULE_APPEND",
[NFT_COMPAT_RULE_INSERT] = "RULE_INSERT",
[NFT_COMPAT_RULE_REPLACE] = "RULE_REPLACE",
[NFT_COMPAT_RULE_DELETE] = "RULE_DELETE",
[NFT_COMPAT_RULE_FLUSH] = "RULE_FLUSH",
};
char errmsg[256];
char tcr[128];
if (o->error.lineno)
snprintf(errmsg, sizeof(errmsg), "\nline %u: %s failed (%s)",
o->error.lineno, type_name[o->type], strerror(err->err));
else
snprintf(errmsg, sizeof(errmsg), " %s failed (%s)",
type_name[o->type], strerror(err->err));
switch (o->type) {
case NFT_COMPAT_TABLE_ADD:
case NFT_COMPAT_TABLE_FLUSH:
snprintf(tcr, sizeof(tcr), "table %s",
nftnl_table_get_str(o->table, NFTNL_TABLE_NAME));
break;
case NFT_COMPAT_CHAIN_ADD:
case NFT_COMPAT_CHAIN_ZERO:
case NFT_COMPAT_CHAIN_USER_ADD:
case NFT_COMPAT_CHAIN_USER_DEL:
case NFT_COMPAT_CHAIN_USER_FLUSH:
case NFT_COMPAT_CHAIN_UPDATE:
case NFT_COMPAT_CHAIN_RENAME:
snprintf(tcr, sizeof(tcr), "chain %s",
nftnl_chain_get_str(o->chain, NFTNL_CHAIN_NAME));
break;
case NFT_COMPAT_RULE_APPEND:
case NFT_COMPAT_RULE_INSERT:
case NFT_COMPAT_RULE_REPLACE:
case NFT_COMPAT_RULE_DELETE:
case NFT_COMPAT_RULE_FLUSH:
snprintf(tcr, sizeof(tcr), "rule in chain %s",
nftnl_rule_get_str(o->rule, NFTNL_RULE_CHAIN));
#if 0
{
nft_rule_print_save(o->rule, NFT_RULE_APPEND, FMT_NOCOUNTS);
}
#endif
break;
}
return snprintf(buf, len, "%s: %s", errmsg, tcr);
}
static int batch_add(struct nft_handle *h, enum obj_update_type type, void *ptr)
{
struct obj_update *obj;
obj = calloc(1, sizeof(struct obj_update));
if (obj == NULL)
return -1;
obj->ptr = ptr;
obj->error.lineno = h->error.lineno;
obj->type = type;
list_add_tail(&obj->head, &h->obj_list);
h->obj_list_num++;
return 0;
}
static int batch_table_add(struct nft_handle *h, enum obj_update_type type,
struct nftnl_table *t)
{
return batch_add(h, type, t);
}
static int batch_chain_add(struct nft_handle *h, enum obj_update_type type,
struct nftnl_chain *c)
{
return batch_add(h, type, c);
}
static int batch_rule_add(struct nft_handle *h, enum obj_update_type type,
struct nftnl_rule *r)
{
return batch_add(h, type, r);
}
struct builtin_table xtables_ipv4[NFT_TABLE_MAX] = {
[NFT_TABLE_RAW] = {
.name = "raw",
.chains = {
{
.name = "PREROUTING",
.type = "filter",
.prio = -300, /* NF_IP_PRI_RAW */
.hook = NF_INET_PRE_ROUTING,
},
{
.name = "OUTPUT",
.type = "filter",
.prio = -300, /* NF_IP_PRI_RAW */
.hook = NF_INET_LOCAL_OUT,
},
},
},
[NFT_TABLE_MANGLE] = {
.name = "mangle",
.chains = {
{
.name = "PREROUTING",
.type = "filter",
.prio = -150, /* NF_IP_PRI_MANGLE */
.hook = NF_INET_PRE_ROUTING,
},
{
.name = "INPUT",
.type = "filter",
.prio = -150, /* NF_IP_PRI_MANGLE */
.hook = NF_INET_LOCAL_IN,
},
{
.name = "FORWARD",
.type = "filter",
.prio = -150, /* NF_IP_PRI_MANGLE */
.hook = NF_INET_FORWARD,
},
{
.name = "OUTPUT",
.type = "route",
.prio = -150, /* NF_IP_PRI_MANGLE */
.hook = NF_INET_LOCAL_OUT,
},
{
.name = "POSTROUTING",
.type = "filter",
.prio = -150, /* NF_IP_PRI_MANGLE */
.hook = NF_INET_POST_ROUTING,
},
},
},
[NFT_TABLE_FILTER] = {
.name = "filter",
.chains = {
{
.name = "INPUT",
.type = "filter",
.prio = 0, /* NF_IP_PRI_FILTER */
.hook = NF_INET_LOCAL_IN,
},
{
.name = "FORWARD",
.type = "filter",
.prio = 0, /* NF_IP_PRI_FILTER */
.hook = NF_INET_FORWARD,
},
{
.name = "OUTPUT",
.type = "filter",
.prio = 0, /* NF_IP_PRI_FILTER */
.hook = NF_INET_LOCAL_OUT,
},
},
},
[NFT_TABLE_SECURITY] = {
.name = "security",
.chains = {
{
.name = "INPUT",
.type = "filter",
.prio = 150, /* NF_IP_PRI_SECURITY */
.hook = NF_INET_LOCAL_IN,
},
{
.name = "FORWARD",
.type = "filter",
.prio = 150, /* NF_IP_PRI_SECURITY */
.hook = NF_INET_FORWARD,
},
{
.name = "OUTPUT",
.type = "filter",
.prio = 150, /* NF_IP_PRI_SECURITY */
.hook = NF_INET_LOCAL_OUT,
},
},
},
[NFT_TABLE_NAT] = {
.name = "nat",
.chains = {
{
.name = "PREROUTING",
.type = "nat",
.prio = -100, /* NF_IP_PRI_NAT_DST */
.hook = NF_INET_PRE_ROUTING,
},
{
.name = "INPUT",
.type = "nat",
.prio = 100, /* NF_IP_PRI_NAT_SRC */
.hook = NF_INET_LOCAL_IN,
},
{
.name = "POSTROUTING",
.type = "nat",
.prio = 100, /* NF_IP_PRI_NAT_SRC */
.hook = NF_INET_POST_ROUTING,
},
{
.name = "OUTPUT",
.type = "nat",
.prio = -100, /* NF_IP_PRI_NAT_DST */
.hook = NF_INET_LOCAL_OUT,
},
},
},
};
#include <linux/netfilter_arp.h>
struct builtin_table xtables_arp[NFT_TABLE_MAX] = {
[NFT_TABLE_FILTER] = {
.name = "filter",
.chains = {
{
.name = "INPUT",
.type = "filter",
.prio = NF_IP_PRI_FILTER,
.hook = NF_ARP_IN,
},
{
.name = "OUTPUT",
.type = "filter",
.prio = NF_IP_PRI_FILTER,
.hook = NF_ARP_OUT,
},
},
},
};
#include <linux/netfilter_bridge.h>
struct builtin_table xtables_bridge[NFT_TABLE_MAX] = {
[NFT_TABLE_FILTER] = {
.name = "filter",
.chains = {
{
.name = "INPUT",
.type = "filter",
.prio = NF_BR_PRI_FILTER_BRIDGED,
.hook = NF_BR_LOCAL_IN,
},
{
.name = "FORWARD",
.type = "filter",
.prio = NF_BR_PRI_FILTER_BRIDGED,
.hook = NF_BR_FORWARD,
},
{
.name = "OUTPUT",
.type = "filter",
.prio = NF_BR_PRI_FILTER_BRIDGED,
.hook = NF_BR_LOCAL_OUT,
},
},
},
[NFT_TABLE_NAT] = {
.name = "nat",
.chains = {
{
.name = "PREROUTING",
.type = "filter",
.prio = NF_BR_PRI_NAT_DST_BRIDGED,
.hook = NF_BR_PRE_ROUTING,
},
{
.name = "OUTPUT",
.type = "filter",
.prio = NF_BR_PRI_NAT_DST_OTHER,
.hook = NF_BR_LOCAL_OUT,
},
{
.name = "POSTROUTING",
.type = "filter",
.prio = NF_BR_PRI_NAT_SRC,
.hook = NF_BR_POST_ROUTING,
},
},
},
};
static int nft_table_builtin_add(struct nft_handle *h,
struct builtin_table *_t)
{
struct nftnl_table *t;
int ret;
if (_t->initialized)
return 0;
t = nftnl_table_alloc();
if (t == NULL)
return -1;
nftnl_table_set(t, NFTNL_TABLE_NAME, (char *)_t->name);
ret = batch_table_add(h, NFT_COMPAT_TABLE_ADD, t);
return ret;
}
static struct nftnl_chain *
nft_chain_builtin_alloc(struct builtin_table *table,
struct builtin_chain *chain, int policy)
{
struct nftnl_chain *c;
c = nftnl_chain_alloc();
if (c == NULL)
return NULL;
nftnl_chain_set(c, NFTNL_CHAIN_TABLE, (char *)table->name);
nftnl_chain_set(c, NFTNL_CHAIN_NAME, (char *)chain->name);
nftnl_chain_set_u32(c, NFTNL_CHAIN_HOOKNUM, chain->hook);
nftnl_chain_set_u32(c, NFTNL_CHAIN_PRIO, chain->prio);
nftnl_chain_set_u32(c, NFTNL_CHAIN_POLICY, policy);
nftnl_chain_set(c, NFTNL_CHAIN_TYPE, (char *)chain->type);
return c;
}
static void nft_chain_builtin_add(struct nft_handle *h,
struct builtin_table *table,
struct builtin_chain *chain)
{
struct nftnl_chain *c;
c = nft_chain_builtin_alloc(table, chain, NF_ACCEPT);
if (c == NULL)
return;
batch_chain_add(h, NFT_COMPAT_CHAIN_ADD, c);
}
/* find if built-in table already exists */
struct builtin_table *
nft_table_builtin_find(struct nft_handle *h, const char *table)
{
int i;
bool found = false;
for (i = 0; i < NFT_TABLE_MAX; i++) {
if (h->tables[i].name == NULL)
continue;
if (strcmp(h->tables[i].name, table) != 0)
continue;
found = true;
break;
}
return found ? &h->tables[i] : NULL;
}
/* find if built-in chain already exists */
struct builtin_chain *
nft_chain_builtin_find(struct builtin_table *t, const char *chain)
{
int i;
bool found = false;
for (i=0; i<NF_IP_NUMHOOKS && t->chains[i].name != NULL; i++) {
if (strcmp(t->chains[i].name, chain) != 0)
continue;
found = true;
break;
}
return found ? &t->chains[i] : NULL;
}
static void nft_chain_builtin_init(struct nft_handle *h,
struct builtin_table *table)
{
struct nftnl_chain_list *list = nft_chain_list_get(h);
struct nftnl_chain *c;
int i;
/* Initialize built-in chains if they don't exist yet */
for (i=0; i < NF_INET_NUMHOOKS && table->chains[i].name != NULL; i++) {
c = nft_chain_list_find(list, table->name,
table->chains[i].name);
if (c != NULL)
continue;
nft_chain_builtin_add(h, table, &table->chains[i]);
}
}
static int nft_xt_builtin_init(struct nft_handle *h, const char *table)
{
struct builtin_table *t;
t = nft_table_builtin_find(h, table);
if (t == NULL)
return -1;
if (t->initialized)
return 0;
if (nft_table_builtin_add(h, t) < 0)
return -1;
nft_chain_builtin_init(h, t);
t->initialized = true;
return 0;
}
static bool nft_chain_builtin(struct nftnl_chain *c)
{
/* Check if this chain has hook number, in that case is built-in.
* Should we better export the flags to user-space via nf_tables?
*/
return nftnl_chain_get(c, NFTNL_CHAIN_HOOKNUM) != NULL;
}
static int nft_restart(struct nft_handle *h)
{
mnl_socket_close(h->nl);
h->nl = mnl_socket_open(NETLINK_NETFILTER);
if (h->nl == NULL)
return -1;
if (mnl_socket_bind(h->nl, 0, MNL_SOCKET_AUTOPID) < 0)
return -1;
h->portid = mnl_socket_get_portid(h->nl);
return 0;
}
int nft_init(struct nft_handle *h, struct builtin_table *t)
{
h->nl = mnl_socket_open(NETLINK_NETFILTER);
if (h->nl == NULL)
return -1;
if (mnl_socket_bind(h->nl, 0, MNL_SOCKET_AUTOPID) < 0) {
mnl_socket_close(h->nl);
return -1;
}
h->portid = mnl_socket_get_portid(h->nl);
h->tables = t;
INIT_LIST_HEAD(&h->obj_list);
INIT_LIST_HEAD(&h->err_list);
return 0;
}
static int __flush_rule_cache(struct nftnl_rule *r, void *data)
{
const char *tablename = data;
if (!strcmp(nftnl_rule_get_str(r, NFTNL_RULE_TABLE), tablename)) {
nftnl_rule_list_del(r);
nftnl_rule_free(r);
}
return 0;
}
static void flush_rule_cache(struct nft_handle *h, const char *tablename)
{
if (!h->rule_cache)
return;
if (tablename) {
nftnl_rule_list_foreach(h->rule_cache, __flush_rule_cache,
(void *)tablename);
} else {
nftnl_rule_list_free(h->rule_cache);
h->rule_cache = NULL;
}
}
static int __flush_chain_cache(struct nftnl_chain *c, void *data)
{
const char *tablename = data;
if (!strcmp(nftnl_chain_get_str(c, NFTNL_CHAIN_TABLE), tablename)) {
nftnl_chain_list_del(c);
nftnl_chain_free(c);
}
return 0;
}
static void flush_chain_cache(struct nft_handle *h, const char *tablename)
{
if (!h->chain_cache)
return;
if (tablename) {
nftnl_chain_list_foreach(h->chain_cache, __flush_chain_cache,
(void *)tablename);
} else {
nftnl_chain_list_free(h->chain_cache);
h->chain_cache = NULL;
}
}
void nft_fini(struct nft_handle *h)
{
flush_chain_cache(h, NULL);
flush_rule_cache(h, NULL);
mnl_socket_close(h->nl);
}
static void nft_chain_print_debug(struct nftnl_chain *c, struct nlmsghdr *nlh)
{
#ifdef NLDEBUG
char tmp[1024];
nftnl_chain_snprintf(tmp, sizeof(tmp), c, 0, 0);
printf("DEBUG: chain: %s\n", tmp);
mnl_nlmsg_fprintf(stdout, nlh, nlh->nlmsg_len, sizeof(struct nfgenmsg));
#endif
}
static struct nftnl_chain *nft_chain_new(struct nft_handle *h,
const char *table, const char *chain,
int policy,
const struct xt_counters *counters)
{
struct nftnl_chain *c;
struct builtin_table *_t;
struct builtin_chain *_c;
_t = nft_table_builtin_find(h, table);
if (!_t) {
errno = ENXIO;
return NULL;
}
/* if this built-in table does not exists, create it */
nft_table_builtin_add(h, _t);
_c = nft_chain_builtin_find(_t, chain);
if (_c != NULL) {
/* This is a built-in chain */
c = nft_chain_builtin_alloc(_t, _c, policy);
if (c == NULL)
return NULL;
} else {
errno = ENOENT;
return NULL;
}
if (counters) {
nftnl_chain_set_u64(c, NFTNL_CHAIN_BYTES,
counters->bcnt);
nftnl_chain_set_u64(c, NFTNL_CHAIN_PACKETS,
counters->pcnt);
}
return c;
}
int nft_chain_set(struct nft_handle *h, const char *table,
const char *chain, const char *policy,
const struct xt_counters *counters)
{
struct nftnl_chain *c = NULL;
int ret;
nft_fn = nft_chain_set;
if (strcmp(policy, "DROP") == 0)
c = nft_chain_new(h, table, chain, NF_DROP, counters);
else if (strcmp(policy, "ACCEPT") == 0)
c = nft_chain_new(h, table, chain, NF_ACCEPT, counters);
else
errno = EINVAL;
if (c == NULL)
return 0;
ret = batch_chain_add(h, NFT_COMPAT_CHAIN_UPDATE, c);
/* the core expects 1 for success and 0 for error */
return ret == 0 ? 1 : 0;
}
static int __add_match(struct nftnl_expr *e, struct xt_entry_match *m)
{
void *info;
nftnl_expr_set(e, NFTNL_EXPR_MT_NAME, m->u.user.name, strlen(m->u.user.name));
nftnl_expr_set_u32(e, NFTNL_EXPR_MT_REV, m->u.user.revision);
info = calloc(1, m->u.match_size);
if (info == NULL)
return -ENOMEM;
memcpy(info, m->data, m->u.match_size - sizeof(*m));
nftnl_expr_set(e, NFTNL_EXPR_MT_INFO, info, m->u.match_size - sizeof(*m));
return 0;
}
static int add_nft_limit(struct nftnl_rule *r, struct xt_entry_match *m)
{
struct xt_rateinfo *rinfo = (void *)m->data;
static const uint32_t mult[] = {
XT_LIMIT_SCALE*24*60*60, /* day */
XT_LIMIT_SCALE*60*60, /* hour */
XT_LIMIT_SCALE*60, /* min */
XT_LIMIT_SCALE, /* sec */
};
struct nftnl_expr *expr;
int i;
expr = nftnl_expr_alloc("limit");
if (!expr)
return -ENOMEM;
for (i = 1; i < ARRAY_SIZE(mult); i++) {
if (rinfo->avg > mult[i] ||
mult[i] / rinfo->avg < mult[i] % rinfo->avg)
break;
}
nftnl_expr_set_u32(expr, NFTNL_EXPR_LIMIT_TYPE, NFT_LIMIT_PKTS);
nftnl_expr_set_u32(expr, NFTNL_EXPR_LIMIT_FLAGS, 0);
nftnl_expr_set_u64(expr, NFTNL_EXPR_LIMIT_RATE,
mult[i - 1] / rinfo->avg);
nftnl_expr_set_u64(expr, NFTNL_EXPR_LIMIT_UNIT,
mult[i - 1] / XT_LIMIT_SCALE);
nftnl_expr_set_u32(expr, NFTNL_EXPR_LIMIT_BURST, rinfo->burst);
nftnl_rule_add_expr(r, expr);
return 0;
}
int add_match(struct nftnl_rule *r, struct xt_entry_match *m)
{
struct nftnl_expr *expr;
int ret;
if (!strcmp(m->u.user.name, "limit"))
return add_nft_limit(r, m);
expr = nftnl_expr_alloc("match");
if (expr == NULL)
return -ENOMEM;
ret = __add_match(expr, m);
nftnl_rule_add_expr(r, expr);
return ret;
}
static int __add_target(struct nftnl_expr *e, struct xt_entry_target *t)
{
void *info;
nftnl_expr_set(e, NFTNL_EXPR_TG_NAME, t->u.user.name,
strlen(t->u.user.name));
nftnl_expr_set_u32(e, NFTNL_EXPR_TG_REV, t->u.user.revision);
info = calloc(1, t->u.target_size);
if (info == NULL)
return -ENOMEM;
memcpy(info, t->data, t->u.target_size - sizeof(*t));
nftnl_expr_set(e, NFTNL_EXPR_TG_INFO, info, t->u.target_size - sizeof(*t));
return 0;
}
static int add_meta_nftrace(struct nftnl_rule *r)
{
struct nftnl_expr *expr;
expr = nftnl_expr_alloc("immediate");
if (expr == NULL)
return -ENOMEM;
nftnl_expr_set_u32(expr, NFTNL_EXPR_IMM_DREG, NFT_REG32_01);
nftnl_expr_set_u8(expr, NFTNL_EXPR_IMM_DATA, 1);
nftnl_rule_add_expr(r, expr);
expr = nftnl_expr_alloc("meta");
if (expr == NULL)
return -ENOMEM;
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_KEY, NFT_META_NFTRACE);
nftnl_expr_set_u32(expr, NFTNL_EXPR_META_SREG, NFT_REG32_01);
nftnl_rule_add_expr(r, expr);
return 0;
}
int add_target(struct nftnl_rule *r, struct xt_entry_target *t)
{
struct nftnl_expr *expr;
int ret;
if (strcmp(t->u.user.name, "TRACE") == 0)
return add_meta_nftrace(r);
expr = nftnl_expr_alloc("target");
if (expr == NULL)
return -ENOMEM;
ret = __add_target(expr, t);
nftnl_rule_add_expr(r, expr);
return ret;
}
int add_jumpto(struct nftnl_rule *r, const char *name, int verdict)
{
struct nftnl_expr *expr;
expr = nftnl_expr_alloc("immediate");
if (expr == NULL)
return -ENOMEM;
nftnl_expr_set_u32(expr, NFTNL_EXPR_IMM_DREG, NFT_REG_VERDICT);
nftnl_expr_set_u32(expr, NFTNL_EXPR_IMM_VERDICT, verdict);
nftnl_expr_set_str(expr, NFTNL_EXPR_IMM_CHAIN, (char *)name);
nftnl_rule_add_expr(r, expr);
return 0;
}
int add_verdict(struct nftnl_rule *r, int verdict)
{
struct nftnl_expr *expr;
expr = nftnl_expr_alloc("immediate");
if (expr == NULL)
return -ENOMEM;
nftnl_expr_set_u32(expr, NFTNL_EXPR_IMM_DREG, NFT_REG_VERDICT);
nftnl_expr_set_u32(expr, NFTNL_EXPR_IMM_VERDICT, verdict);
nftnl_rule_add_expr(r, expr);
return 0;
}
int add_action(struct nftnl_rule *r, struct iptables_command_state *cs,
bool goto_set)
{
int ret = 0;
/* If no target at all, add nothing (default to continue) */
if (cs->target != NULL) {
/* Standard target? */
if (strcmp(cs->jumpto, XTC_LABEL_ACCEPT) == 0)
ret = add_verdict(r, NF_ACCEPT);
else if (strcmp(cs->jumpto, XTC_LABEL_DROP) == 0)
ret = add_verdict(r, NF_DROP);
else if (strcmp(cs->jumpto, XTC_LABEL_RETURN) == 0)
ret = add_verdict(r, NFT_RETURN);
else
ret = add_target(r, cs->target->t);
} else if (strlen(cs->jumpto) > 0) {
/* Not standard, then it's a go / jump to chain */
if (goto_set)
ret = add_jumpto(r, cs->jumpto, NFT_GOTO);
else
ret = add_jumpto(r, cs->jumpto, NFT_JUMP);
}
return ret;
}
static void nft_rule_print_debug(struct nftnl_rule *r, struct nlmsghdr *nlh)
{
#ifdef NLDEBUG
char tmp[1024];
nftnl_rule_snprintf(tmp, sizeof(tmp), r, 0, 0);
printf("DEBUG: rule: %s\n", tmp);
mnl_nlmsg_fprintf(stdout, nlh, nlh->nlmsg_len, sizeof(struct nfgenmsg));
#endif
}
int add_counters(struct nftnl_rule *r, uint64_t packets, uint64_t bytes)
{
struct nftnl_expr *expr;
expr = nftnl_expr_alloc("counter");
if (expr == NULL)
return -ENOMEM;
nftnl_expr_set_u64(expr, NFTNL_EXPR_CTR_PACKETS, packets);
nftnl_expr_set_u64(expr, NFTNL_EXPR_CTR_BYTES, bytes);
nftnl_rule_add_expr(r, expr);
return 0;
}
enum udata_type {
UDATA_TYPE_COMMENT,
__UDATA_TYPE_MAX,
};
#define UDATA_TYPE_MAX (__UDATA_TYPE_MAX - 1)
int add_comment(struct nftnl_rule *r, const char *comment)
{
struct nftnl_udata_buf *udata;
uint32_t len;
if (nftnl_rule_get_data(r, NFTNL_RULE_USERDATA, &len))
return -EALREADY;
udata = nftnl_udata_buf_alloc(NFT_USERDATA_MAXLEN);
if (!udata)
return -ENOMEM;
if (strnlen(comment, 255) == 255)
return -ENOSPC;
if (!nftnl_udata_put_strz(udata, UDATA_TYPE_COMMENT, comment))
return -ENOMEM;
nftnl_rule_set_data(r, NFTNL_RULE_USERDATA,
nftnl_udata_buf_data(udata),
nftnl_udata_buf_len(udata));
nftnl_udata_buf_free(udata);
return 0;
}
static int parse_udata_cb(const struct nftnl_udata *attr, void *data)
{
unsigned char *value = nftnl_udata_get(attr);
uint8_t type = nftnl_udata_type(attr);
uint8_t len = nftnl_udata_len(attr);
const struct nftnl_udata **tb = data;
switch (type) {
case UDATA_TYPE_COMMENT:
if (value[len - 1] != '\0')
return -1;
break;
default:
return 0;
}
tb[type] = attr;
return 0;
}
char *get_comment(const void *data, uint32_t data_len)
{
const struct nftnl_udata *tb[UDATA_TYPE_MAX + 1] = {};
if (nftnl_udata_parse(data, data_len, parse_udata_cb, tb) < 0)
return NULL;
if (!tb[UDATA_TYPE_COMMENT])
return NULL;
return nftnl_udata_get(tb[UDATA_TYPE_COMMENT]);
}
void add_compat(struct nftnl_rule *r, uint32_t proto, bool inv)
{
nftnl_rule_set_u32(r, NFTNL_RULE_COMPAT_PROTO, proto);
nftnl_rule_set_u32(r, NFTNL_RULE_COMPAT_FLAGS,
inv ? NFT_RULE_COMPAT_F_INV : 0);
}
static struct nftnl_rule *
nft_rule_new(struct nft_handle *h, const char *chain, const char *table,
void *data)
{
struct nftnl_rule *r;
r = nftnl_rule_alloc();
if (r == NULL)
return NULL;
nftnl_rule_set_u32(r, NFTNL_RULE_FAMILY, h->family);
nftnl_rule_set(r, NFTNL_RULE_TABLE, (char *)table);
nftnl_rule_set(r, NFTNL_RULE_CHAIN, (char *)chain);
if (h->ops->add(r, data) < 0)
goto err;
return r;
err:
nftnl_rule_free(r);
return NULL;
}
static struct nftnl_rule_list *nft_rule_list_get(struct nft_handle *h);
int
nft_rule_append(struct nft_handle *h, const char *chain, const char *table,
void *data, uint64_t handle, bool verbose)
{
struct nftnl_rule *r;
int type;
/* If built-in chains don't exist for this table, create them */
if (nft_xtables_config_load(h, XTABLES_CONFIG_DEFAULT, 0) < 0)
nft_xt_builtin_init(h, table);
nft_fn = nft_rule_append;
r = nft_rule_new(h, chain, table, data);
if (r == NULL)
return 0;
if (handle > 0) {
nftnl_rule_set(r, NFTNL_RULE_HANDLE, &handle);
type = NFT_COMPAT_RULE_REPLACE;
} else
type = NFT_COMPAT_RULE_APPEND;
if (batch_rule_add(h, type, r) < 0) {
nftnl_rule_free(r);
return 0;
}
if (verbose)
h->ops->print_rule(r, 0, FMT_PRINT_RULE);
if (!nft_rule_list_get(h))
return 0;
nftnl_rule_list_add_tail(r, h->rule_cache);
return 1;
}
void
nft_rule_print_save(const struct nftnl_rule *r, enum nft_rule_print type,
unsigned int format)
{
const char *chain = nftnl_rule_get_str(r, NFTNL_RULE_CHAIN);
int family = nftnl_rule_get_u32(r, NFTNL_RULE_FAMILY);
struct iptables_command_state cs = {};
struct nft_family_ops *ops;
ops = nft_family_ops_lookup(family);
ops->rule_to_cs(r, &cs);
if (!(format & (FMT_NOCOUNTS | FMT_C_COUNTS)) && ops->save_counters)
ops->save_counters(&cs);
/* print chain name */
switch(type) {
case NFT_RULE_APPEND:
printf("-A %s ", chain);
break;
case NFT_RULE_DEL:
printf("-D %s ", chain);
break;
}
if (ops->save_rule)
ops->save_rule(&cs, format);
if (ops->clear_cs)
ops->clear_cs(&cs);
}
static int nftnl_chain_list_cb(const struct nlmsghdr *nlh, void *data)
{
struct nftnl_chain *c;
struct nftnl_chain_list *list = data;
c = nftnl_chain_alloc();
if (c == NULL)
goto err;
if (nftnl_chain_nlmsg_parse(nlh, c) < 0)
goto out;
nftnl_chain_list_add_tail(c, list);
return MNL_CB_OK;
out:
nftnl_chain_free(c);
err:
return MNL_CB_OK;
}
struct nftnl_chain_list *nft_chain_list_get(struct nft_handle *h)
{
char buf[16536];
struct nlmsghdr *nlh;
struct nftnl_chain_list *list;
int ret;
if (h->chain_cache)
return h->chain_cache;
retry:
list = nftnl_chain_list_alloc();
if (list == NULL) {
errno = ENOMEM;
return NULL;
}
nlh = nftnl_chain_nlmsg_build_hdr(buf, NFT_MSG_GETCHAIN, h->family,
NLM_F_DUMP, h->seq);
ret = mnl_talk(h, nlh, nftnl_chain_list_cb, list);
if (ret < 0 && errno == EINTR) {
assert(nft_restart(h) >= 0);
nftnl_chain_list_free(list);
goto retry;
}
h->chain_cache = list;
return list;
}
static const char *policy_name[NF_ACCEPT+1] = {
[NF_DROP] = "DROP",
[NF_ACCEPT] = "ACCEPT",
};
int nft_chain_save(struct nft_handle *h, struct nftnl_chain_list *list,
const char *table)
{
struct nftnl_chain_list_iter *iter;
struct nft_family_ops *ops;
struct nftnl_chain *c;
ops = nft_family_ops_lookup(h->family);
iter = nftnl_chain_list_iter_create(list);
if (iter == NULL)
return 0;
c = nftnl_chain_list_iter_next(iter);
while (c != NULL) {
const char *chain_table =
nftnl_chain_get_str(c, NFTNL_CHAIN_TABLE);
const char *policy = NULL;
if (strcmp(table, chain_table) != 0)
goto next;
if (nft_chain_builtin(c)) {
uint32_t pol = NF_ACCEPT;
if (nftnl_chain_get(c, NFTNL_CHAIN_POLICY))
pol = nftnl_chain_get_u32(c, NFTNL_CHAIN_POLICY);
policy = policy_name[pol];
}
if (ops->save_chain)
ops->save_chain(c, policy);
next:
c = nftnl_chain_list_iter_next(iter);
}
nftnl_chain_list_iter_destroy(iter);
return 1;
}
static int nftnl_rule_list_cb(const struct nlmsghdr *nlh, void *data)
{
struct nftnl_rule *r;
struct nftnl_rule_list *list = data;
r = nftnl_rule_alloc();
if (r == NULL)
goto err;
if (nftnl_rule_nlmsg_parse(nlh, r) < 0)
goto out;
nftnl_rule_list_add_tail(r, list);
return MNL_CB_OK;
out:
nftnl_rule_free(r);
nftnl_rule_list_free(list);
err:
return MNL_CB_OK;
}
static struct nftnl_rule_list *nft_rule_list_get(struct nft_handle *h)
{
char buf[16536];
struct nlmsghdr *nlh;
struct nftnl_rule_list *list;
int ret;
if (h->rule_cache)
return h->rule_cache;
retry:
list = nftnl_rule_list_alloc();
if (list == NULL)
return 0;
nlh = nftnl_rule_nlmsg_build_hdr(buf, NFT_MSG_GETRULE, h->family,
NLM_F_DUMP, h->seq);
ret = mnl_talk(h, nlh, nftnl_rule_list_cb, list);
if (ret < 0) {
if (errno == EINTR) {
assert(nft_restart(h) >= 0);
nftnl_rule_list_free(list);
goto retry;
}
nftnl_rule_list_free(list);
return NULL;
}
h->rule_cache = list;
return list;
}
int nft_rule_save(struct nft_handle *h, const char *table, unsigned int format)
{
struct nftnl_rule_list *list;
struct nftnl_rule_list_iter *iter;
struct nftnl_rule *r;
list = nft_rule_list_get(h);
if (list == NULL)
return 0;
iter = nftnl_rule_list_iter_create(list);
if (iter == NULL)
return 0;
r = nftnl_rule_list_iter_next(iter);
while (r != NULL) {
const char *rule_table =
nftnl_rule_get_str(r, NFTNL_RULE_TABLE);
if (strcmp(table, rule_table) != 0)
goto next;
nft_rule_print_save(r, NFT_RULE_APPEND, format);
next:
r = nftnl_rule_list_iter_next(iter);
}
nftnl_rule_list_iter_destroy(iter);
/* the core expects 1 for success and 0 for error */
return 1;
}
static void
__nft_rule_flush(struct nft_handle *h, const char *table, const char *chain)
{
struct nftnl_rule *r;
r = nftnl_rule_alloc();
if (r == NULL)
return;
nftnl_rule_set(r, NFTNL_RULE_TABLE, (char *)table);
nftnl_rule_set(r, NFTNL_RULE_CHAIN, (char *)chain);
if (batch_rule_add(h, NFT_COMPAT_RULE_FLUSH, r) < 0)
nftnl_rule_free(r);
}
struct chain_user_flush_data {
struct nft_handle *handle;
const char *table;
const char *chain;
};
static int __nft_chain_user_flush(struct nftnl_chain *c, void *data)
{
const char *table_name = nftnl_chain_get_str(c, NFTNL_CHAIN_TABLE);
const char *chain_name = nftnl_chain_get_str(c, NFTNL_CHAIN_NAME);
struct chain_user_flush_data *d = data;
struct nft_handle *h = d->handle;
const char *table = d->table;
const char *chain = d->chain;
if (strcmp(table, table_name) != 0)
return 0;
if (strcmp(chain, chain_name) != 0)
return 0;
if (!nftnl_chain_is_set(c, NFTNL_CHAIN_HOOKNUM))
__nft_rule_flush(h, table, chain);
return 0;
}
int nft_chain_user_flush(struct nft_handle *h, struct nftnl_chain_list *list,
const char *table, const char *chain)
{
struct chain_user_flush_data d = {
.handle = h,
.table = table,
.chain = chain,
};
nft_fn = nft_chain_user_flush;
nftnl_chain_list_foreach(list, __nft_chain_user_flush, &d);
return 1;
}
int nft_rule_flush(struct nft_handle *h, const char *chain, const char *table,
bool verbose)
{
int ret = 0;
struct nftnl_chain_list *list;
struct nftnl_chain_list_iter *iter;
struct nftnl_chain *c;
if (nft_xtables_config_load(h, XTABLES_CONFIG_DEFAULT, 0) < 0)
nft_xt_builtin_init(h, table);
nft_fn = nft_rule_flush;
list = nft_chain_list_get(h);
if (list == NULL) {
ret = 1;
goto err;
}
iter = nftnl_chain_list_iter_create(list);
if (iter == NULL) {
ret = 1;
goto err;
}
c = nftnl_chain_list_iter_next(iter);
while (c != NULL) {
const char *table_name =
nftnl_chain_get_str(c, NFTNL_CHAIN_TABLE);
const char *chain_name =
nftnl_chain_get_str(c, NFTNL_CHAIN_NAME);
if (strcmp(table, table_name) != 0)
goto next;
if (chain != NULL && strcmp(chain, chain_name) != 0)
goto next;
if (verbose)
fprintf(stdout, "Flushing chain `%s'\n", chain_name);
__nft_rule_flush(h, table_name, chain_name);
if (chain != NULL)
break;
next:
c = nftnl_chain_list_iter_next(iter);
}
nftnl_chain_list_iter_destroy(iter);
flush_rule_cache(h, table);
err:
/* the core expects 1 for success and 0 for error */
return ret == 0 ? 1 : 0;
}
int nft_chain_user_add(struct nft_handle *h, const char *chain, const char *table)
{
struct nftnl_chain *c;
int ret;
nft_fn = nft_chain_user_add;
/* If built-in chains don't exist for this table, create them */
if (nft_xtables_config_load(h, XTABLES_CONFIG_DEFAULT, 0) < 0)
nft_xt_builtin_init(h, table);
c = nftnl_chain_alloc();
if (c == NULL)
return 0;
nftnl_chain_set(c, NFTNL_CHAIN_TABLE, (char *)table);
nftnl_chain_set(c, NFTNL_CHAIN_NAME, (char *)chain);
ret = batch_chain_add(h, NFT_COMPAT_CHAIN_USER_ADD, c);
nft_chain_list_get(h);
nftnl_chain_list_add(c, h->chain_cache);
/* the core expects 1 for success and 0 for error */
return ret == 0 ? 1 : 0;
}
/* From linux/netlink.h */
#ifndef NLM_F_NONREC
#define NLM_F_NONREC 0x100 /* Do not delete recursively */
#endif
int nft_chain_user_del(struct nft_handle *h, const char *chain,
const char *table, bool verbose)
{
struct nftnl_chain_list *list;
struct nftnl_chain_list_iter *iter;
struct nftnl_chain *c;
int ret = 0;
int deleted_ctr = 0;
nft_fn = nft_chain_user_del;
list = nft_chain_list_get(h);
if (list == NULL)
goto err;
iter = nftnl_chain_list_iter_create(list);
if (iter == NULL)
goto err;
c = nftnl_chain_list_iter_next(iter);
while (c != NULL) {
const char *table_name =
nftnl_chain_get_str(c, NFTNL_CHAIN_TABLE);
const char *chain_name =
nftnl_chain_get_str(c, NFTNL_CHAIN_NAME);
/* don't delete built-in chain */
if (nft_chain_builtin(c))
goto next;
if (strcmp(table, table_name) != 0)
goto next;
if (chain != NULL && strcmp(chain, chain_name) != 0)
goto next;
if (verbose)
fprintf(stdout, "Deleting chain `%s'\n", chain);
ret = batch_chain_add(h, NFT_COMPAT_CHAIN_USER_DEL, c);
if (ret < 0)
break;
deleted_ctr++;
nftnl_chain_list_del(c);
if (chain != NULL)
break;
next:
c = nftnl_chain_list_iter_next(iter);
}
nftnl_chain_list_iter_destroy(iter);
err:
/* chain not found */
if (chain != NULL && deleted_ctr == 0) {
ret = -1;
errno = ENOENT;
}
/* the core expects 1 for success and 0 for error */
return ret == 0 ? 1 : 0;
}
struct nftnl_chain *
nft_chain_list_find(struct nftnl_chain_list *list,
const char *table, const char *chain)
{
struct nftnl_chain_list_iter *iter;
struct nftnl_chain *c;
iter = nftnl_chain_list_iter_create(list);
if (iter == NULL)
return NULL;
c = nftnl_chain_list_iter_next(iter);
while (c != NULL) {
const char *table_name =
nftnl_chain_get_str(c, NFTNL_CHAIN_TABLE);
const char *chain_name =
nftnl_chain_get_str(c, NFTNL_CHAIN_NAME);
if (strcmp(table, table_name) != 0)
goto next;
if (strcmp(chain, chain_name) != 0)
goto next;
nftnl_chain_list_iter_destroy(iter);
return c;
next:
c = nftnl_chain_list_iter_next(iter);
}
nftnl_chain_list_iter_destroy(iter);
return NULL;
}
static struct nftnl_chain *
nft_chain_find(struct nft_handle *h, const char *table, const char *chain)
{
struct nftnl_chain_list *list;
list = nft_chain_list_get(h);
if (list == NULL)
return NULL;
return nft_chain_list_find(list, table, chain);
}
bool nft_chain_exists(struct nft_handle *h,
const char *table, const char *chain)
{
struct builtin_table *t = nft_table_builtin_find(h, table);
/* xtables does not support custom tables */
if (!t)
return false;
if (nft_chain_builtin_find(t, chain))
return true;
return !!nft_chain_find(h, table, chain);
}
int nft_chain_user_rename(struct nft_handle *h,const char *chain,
const char *table, const char *newname)
{
struct nftnl_chain *c;
uint64_t handle;
int ret;
nft_fn = nft_chain_user_add;
/* If built-in chains don't exist for this table, create them */
if (nft_xtables_config_load(h, XTABLES_CONFIG_DEFAULT, 0) < 0)
nft_xt_builtin_init(h, table);
/* Config load changed errno. Ensure genuine info for our callers. */
errno = 0;
/* Find the old chain to be renamed */
c = nft_chain_find(h, table, chain);
if (c == NULL) {
errno = ENOENT;
return 0;
}
handle = nftnl_chain_get_u64(c, NFTNL_CHAIN_HANDLE);
/* Now prepare the new name for the chain */
c = nftnl_chain_alloc();
if (c == NULL)
return 0;
nftnl_chain_set(c, NFTNL_CHAIN_TABLE, (char *)table);
nftnl_chain_set(c, NFTNL_CHAIN_NAME, (char *)newname);
nftnl_chain_set_u64(c, NFTNL_CHAIN_HANDLE, handle);
ret = batch_chain_add(h, NFT_COMPAT_CHAIN_RENAME, c);
/* the core expects 1 for success and 0 for error */
return ret == 0 ? 1 : 0;
}
static int nftnl_table_list_cb(const struct nlmsghdr *nlh, void *data)
{
struct nftnl_table *t;
struct nftnl_table_list *list = data;
t = nftnl_table_alloc();
if (t == NULL)
goto err;
if (nftnl_table_nlmsg_parse(nlh, t) < 0)
goto out;
nftnl_table_list_add_tail(t, list);
return MNL_CB_OK;
out:
nftnl_table_free(t);
err:
return MNL_CB_OK;
}
static struct nftnl_table_list *nftnl_table_list_get(struct nft_handle *h)
{
char buf[16536];
struct nlmsghdr *nlh;
struct nftnl_table_list *list;
int ret;
retry:
list = nftnl_table_list_alloc();
if (list == NULL)
return 0;
nlh = nftnl_rule_nlmsg_build_hdr(buf, NFT_MSG_GETTABLE, h->family,
NLM_F_DUMP, h->seq);
ret = mnl_talk(h, nlh, nftnl_table_list_cb, list);
if (ret < 0 && errno == EINTR) {
assert(nft_restart(h) >= 0);
nftnl_table_list_free(list);
goto retry;
}
return list;
}
bool nft_table_find(struct nft_handle *h, const char *tablename)
{
struct nftnl_table_list *list;
struct nftnl_table_list_iter *iter;
struct nftnl_table *t;
bool ret = false;
list = nftnl_table_list_get(h);
if (list == NULL)
goto err;
iter = nftnl_table_list_iter_create(list);
if (iter == NULL)
goto err;
t = nftnl_table_list_iter_next(iter);
while (t != NULL) {
const char *this_tablename =
nftnl_table_get(t, NFTNL_TABLE_NAME);
if (strcmp(tablename, this_tablename) == 0) {
ret = true;
break;
}
t = nftnl_table_list_iter_next(iter);
}
nftnl_table_list_iter_destroy(iter);
nftnl_table_list_free(list);
err:
return ret;
}
int nft_for_each_table(struct nft_handle *h,
int (*func)(struct nft_handle *h, const char *tablename, bool counters),
bool counters)
{
struct nftnl_table_list *list;
struct nftnl_table_list_iter *iter;
struct nftnl_table *t;
list = nftnl_table_list_get(h);
if (list == NULL)
return -1;
iter = nftnl_table_list_iter_create(list);
if (iter == NULL)
return -1;
t = nftnl_table_list_iter_next(iter);
while (t != NULL) {
const char *tablename =
nftnl_table_get(t, NFTNL_TABLE_NAME);
func(h, tablename, counters);
t = nftnl_table_list_iter_next(iter);
}
nftnl_table_list_iter_destroy(iter);
nftnl_table_list_free(list);
return 0;
}
static int __nft_table_flush(struct nft_handle *h, const char *table)
{
struct builtin_table *_t;
struct nftnl_table *t;
t = nftnl_table_alloc();
if (t == NULL)
return -1;
nftnl_table_set_str(t, NFTNL_TABLE_NAME, table);
batch_table_add(h, NFT_COMPAT_TABLE_FLUSH, t);
_t = nft_table_builtin_find(h, table);
assert(_t);
_t->initialized = false;
flush_chain_cache(h, table);
flush_rule_cache(h, table);
return 0;
}
int nft_table_flush(struct nft_handle *h, const char *table)
{
struct nftnl_table_list_iter *iter;
struct nftnl_table_list *list;
struct nftnl_table *t;
int ret = 0;
nft_fn = nft_table_flush;
list = nftnl_table_list_get(h);
if (list == NULL) {
ret = -1;
goto err_out;
}
iter = nftnl_table_list_iter_create(list);
if (iter == NULL) {
ret = -1;
goto err_table_list;
}
t = nftnl_table_list_iter_next(iter);
while (t != NULL) {
const char *table_name =
nftnl_table_get_str(t, NFTNL_TABLE_NAME);
if (strcmp(table_name, table) != 0)
goto next;
ret = __nft_table_flush(h, table);
if (ret < 0)
goto err_table_iter;
next:
t = nftnl_table_list_iter_next(iter);
}
if (!h->rule_cache) {
h->rule_cache = nftnl_rule_list_alloc();
if (h->rule_cache == NULL)
return -1;
}
err_table_iter:
nftnl_table_list_iter_destroy(iter);
err_table_list:
nftnl_table_list_free(list);
err_out:
/* the core expects 1 for success and 0 for error */
return ret == 0 ? 1 : 0;
}
void nft_table_new(struct nft_handle *h, const char *table)
{
if (nft_xtables_config_load(h, XTABLES_CONFIG_DEFAULT, 0) < 0)
nft_xt_builtin_init(h, table);
}
static int __nft_rule_del(struct nft_handle *h, struct nftnl_rule_list *list,
struct nftnl_rule *r)
{
int ret;
nftnl_rule_list_del(r);
ret = batch_rule_add(h, NFT_COMPAT_RULE_DELETE, r);
if (ret < 0) {
nftnl_rule_free(r);
return -1;
}
return 1;
}
static struct nftnl_rule *
nft_rule_find(struct nft_handle *h, struct nftnl_rule_list *list,
const char *chain, const char *table, void *data, int rulenum)
{
struct nftnl_rule *r;
struct nftnl_rule_list_iter *iter;
int rule_ctr = 0;
bool found = false;
iter = nftnl_rule_list_iter_create(list);
if (iter == NULL)
return 0;
r = nftnl_rule_list_iter_next(iter);
while (r != NULL) {
const char *rule_table =
nftnl_rule_get_str(r, NFTNL_RULE_TABLE);
const char *rule_chain =
nftnl_rule_get_str(r, NFTNL_RULE_CHAIN);
if (strcmp(table, rule_table) != 0 ||
strcmp(chain, rule_chain) != 0) {
DEBUGP("different chain / table\n");
goto next;
}
if (rulenum >= 0) {
/* Delete by rule number case */
if (rule_ctr == rulenum) {
found = true;
break;
}
} else {
found = h->ops->rule_find(h->ops, r, data);
if (found)
break;
}
rule_ctr++;
next:
r = nftnl_rule_list_iter_next(iter);
}
nftnl_rule_list_iter_destroy(iter);
return found ? r : NULL;
}
int nft_rule_check(struct nft_handle *h, const char *chain,
const char *table, void *data, bool verbose)
{
struct nftnl_rule_list *list;
struct nftnl_rule *r;
nft_fn = nft_rule_check;
list = nft_rule_list_get(h);
if (list == NULL)
return 0;
r = nft_rule_find(h, list, chain, table, data, -1);
if (r == NULL) {
errno = ENOENT;
return 0;
}
if (verbose)
h->ops->print_rule(r, 0, FMT_PRINT_RULE);
return 1;
}
int nft_rule_delete(struct nft_handle *h, const char *chain,
const char *table, void *data, bool verbose)
{
int ret = 0;
struct nftnl_rule *r;
struct nftnl_rule_list *list;
nft_fn = nft_rule_delete;
list = nft_rule_list_get(h);
if (list == NULL)
return 0;
r = nft_rule_find(h, list, chain, table, data, -1);
if (r != NULL) {
ret =__nft_rule_del(h, list, r);
if (ret < 0)
errno = ENOMEM;
if (verbose)
h->ops->print_rule(r, 0, FMT_PRINT_RULE);
} else
errno = ENOENT;
return ret;
}
static struct nftnl_rule *
nft_rule_add(struct nft_handle *h, const char *chain,
const char *table, struct iptables_command_state *cs,
uint64_t handle, bool verbose)
{
struct nftnl_rule *r;
r = nft_rule_new(h, chain, table, cs);
if (r == NULL)
return NULL;
if (handle > 0)
nftnl_rule_set_u64(r, NFTNL_RULE_POSITION, handle);
if (batch_rule_add(h, NFT_COMPAT_RULE_INSERT, r) < 0) {
nftnl_rule_free(r);
return NULL;
}
if (verbose)
h->ops->print_rule(r, 0, FMT_PRINT_RULE);
return r;
}
int nft_rule_insert(struct nft_handle *h, const char *chain,
const char *table, void *data, int rulenum, bool verbose)
{
struct nftnl_rule *r, *new_rule;
struct nftnl_rule_list *list;
uint64_t handle = 0;
/* If built-in chains don't exist for this table, create them */
if (nft_xtables_config_load(h, XTABLES_CONFIG_DEFAULT, 0) < 0)
nft_xt_builtin_init(h, table);
nft_fn = nft_rule_insert;
if (rulenum > 0) {
list = nft_rule_list_get(h);
if (list == NULL)
goto err;
r = nft_rule_find(h, list, chain, table, data, rulenum);
if (r == NULL) {
/* special case: iptables allows to insert into
* rule_count + 1 position.
*/
r = nft_rule_find(h, list, chain, table, data,
rulenum - 1);
if (r != NULL)
return nft_rule_append(h, chain, table, data,
0, verbose);
errno = ENOENT;
goto err;
}
handle = nftnl_rule_get_u64(r, NFTNL_RULE_HANDLE);
DEBUGP("adding after rule handle %"PRIu64"\n", handle);
} else {
nft_rule_list_get(h);
}
new_rule = nft_rule_add(h, chain, table, data, handle, verbose);
if (!new_rule)
goto err;
if (handle)
nftnl_rule_list_insert_at(new_rule, r);
else
nftnl_rule_list_add(new_rule, h->rule_cache);
return 1;
err:
return 0;
}
int nft_rule_delete_num(struct nft_handle *h, const char *chain,
const char *table, int rulenum, bool verbose)
{
int ret = 0;
struct nftnl_rule *r;
struct nftnl_rule_list *list;
nft_fn = nft_rule_delete_num;
list = nft_rule_list_get(h);
if (list == NULL)
return 0;
r = nft_rule_find(h, list, chain, table, NULL, rulenum);
if (r != NULL) {
DEBUGP("deleting rule by number %d\n", rulenum);
ret = __nft_rule_del(h, list, r);
if (ret < 0)
errno = ENOMEM;
} else
errno = ENOENT;
return ret;
}
int nft_rule_replace(struct nft_handle *h, const char *chain,
const char *table, void *data, int rulenum, bool verbose)
{
int ret = 0;
struct nftnl_rule *r;
struct nftnl_rule_list *list;
nft_fn = nft_rule_replace;
list = nft_rule_list_get(h);
if (list == NULL)
return 0;
r = nft_rule_find(h, list, chain, table, data, rulenum);
if (r != NULL) {
DEBUGP("replacing rule with handle=%llu\n",
(unsigned long long)
nftnl_rule_get_u64(r, NFTNL_RULE_HANDLE));
nftnl_rule_list_del(r);
ret = nft_rule_append(h, chain, table, data,
nftnl_rule_get_u64(r, NFTNL_RULE_HANDLE),
verbose);
} else
errno = ENOENT;
return ret;
}
static int
__nft_rule_list(struct nft_handle *h, const char *chain, const char *table,
int rulenum, unsigned int format,
void (*cb)(struct nftnl_rule *r, unsigned int num,
unsigned int format))
{
struct nftnl_rule_list *list;
struct nftnl_rule_list_iter *iter;
struct nftnl_rule *r;
int rule_ctr = 0;
list = nft_rule_list_get(h);
if (list == NULL)
return 0;
iter = nftnl_rule_list_iter_create(list);
if (iter == NULL)
return 0;
r = nftnl_rule_list_iter_next(iter);
while (r != NULL) {
const char *rule_table =
nftnl_rule_get_str(r, NFTNL_RULE_TABLE);
const char *rule_chain =
nftnl_rule_get_str(r, NFTNL_RULE_CHAIN);
if (strcmp(table, rule_table) != 0 ||
strcmp(chain, rule_chain) != 0)
goto next;
rule_ctr++;
if (rulenum > 0 && rule_ctr != rulenum) {
/* List by rule number case */
goto next;
}
cb(r, rule_ctr, format);
if (rulenum > 0)
break;
next:
r = nftnl_rule_list_iter_next(iter);
}
nftnl_rule_list_iter_destroy(iter);
return 1;
}
static int nft_rule_count(struct nft_handle *h,
const char *chain, const char *table)
{
struct nftnl_rule_list_iter *iter;
struct nftnl_rule_list *list;
struct nftnl_rule *r;
int rule_ctr = 0;
list = nft_rule_list_get(h);
if (list == NULL)
return 0;
iter = nftnl_rule_list_iter_create(list);
if (iter == NULL)
return 0;
r = nftnl_rule_list_iter_next(iter);
while (r != NULL) {
const char *rule_table =
nftnl_rule_get_str(r, NFTNL_RULE_TABLE);
const char *rule_chain =
nftnl_rule_get_str(r, NFTNL_RULE_CHAIN);
if (strcmp(table, rule_table) != 0 ||
strcmp(chain, rule_chain) != 0)
goto next;
rule_ctr++;
next:
r = nftnl_rule_list_iter_next(iter);
}
nftnl_rule_list_iter_destroy(iter);
return rule_ctr;
}
int nft_rule_list(struct nft_handle *h, const char *chain, const char *table,
int rulenum, unsigned int format)
{
const struct nft_family_ops *ops;
struct nftnl_chain_list *list;
struct nftnl_chain_list_iter *iter;
struct nftnl_chain *c;
bool found = false;
/* If built-in chains don't exist for this table, create them */
if (nft_xtables_config_load(h, XTABLES_CONFIG_DEFAULT, 0) < 0) {
nft_xt_builtin_init(h, table);
/* Force table and chain creation, otherwise first iptables -L
* lists no table/chains.
*/
if (!list_empty(&h->obj_list)) {
nft_commit(h);
flush_chain_cache(h, NULL);
}
}
ops = nft_family_ops_lookup(h->family);
if (!nft_is_table_compatible(h, table)) {
xtables_error(OTHER_PROBLEM, "table `%s' is incompatible, use 'nft' tool.\n", table);
return 0;
}
if (chain && rulenum) {
__nft_rule_list(h, chain, table,
rulenum, format, ops->print_rule);
return 1;
}
list = nft_chain_list_get(h);
iter = nftnl_chain_list_iter_create(list);
if (iter == NULL)
goto err;
if (!chain && ops->print_table_header)
ops->print_table_header(table);
c = nftnl_chain_list_iter_next(iter);
while (c != NULL) {
const char *chain_table =
nftnl_chain_get_str(c, NFTNL_CHAIN_TABLE);
const char *chain_name =
nftnl_chain_get_str(c, NFTNL_CHAIN_NAME);
uint32_t policy =
nftnl_chain_get_u32(c, NFTNL_CHAIN_POLICY);
uint32_t refs =
nftnl_chain_get_u32(c, NFTNL_CHAIN_USE);
struct xt_counters ctrs = {
.pcnt = nftnl_chain_get_u64(c, NFTNL_CHAIN_PACKETS),
.bcnt = nftnl_chain_get_u64(c, NFTNL_CHAIN_BYTES),
};
bool basechain = false;
uint32_t entries;
if (nftnl_chain_get(c, NFTNL_CHAIN_HOOKNUM))
basechain = true;
if (strcmp(table, chain_table) != 0)
goto next;
if (chain) {
if (strcmp(chain, chain_name) != 0)
goto next;
else if (ops->print_table_header)
ops->print_table_header(table);
}
if (found)
printf("\n");
entries = nft_rule_count(h, chain_name, table);
ops->print_header(format, chain_name, policy_name[policy],
&ctrs, basechain, refs - entries, entries);
__nft_rule_list(h, chain_name, table,
rulenum, format, ops->print_rule);
found = true;
/* we printed the chain we wanted, stop processing. */
if (chain)
break;
next:
c = nftnl_chain_list_iter_next(iter);
}
nftnl_chain_list_iter_destroy(iter);
err:
if (chain && !found)
return 0;
return 1;
}
static void
list_save(struct nftnl_rule *r, unsigned int num, unsigned int format)
{
nft_rule_print_save(r, NFT_RULE_APPEND, format);
}
static int
nftnl_rule_list_chain_save(struct nft_handle *h, const char *chain,
const char *table, struct nftnl_chain_list *list,
int counters)
{
struct nftnl_chain_list_iter *iter;
struct nftnl_chain *c;
iter = nftnl_chain_list_iter_create(list);
if (iter == NULL)
return 0;
c = nftnl_chain_list_iter_next(iter);
while (c != NULL) {
const char *chain_table =
nftnl_chain_get_str(c, NFTNL_CHAIN_TABLE);
const char *chain_name =
nftnl_chain_get_str(c, NFTNL_CHAIN_NAME);
uint32_t policy =
nftnl_chain_get_u32(c, NFTNL_CHAIN_POLICY);
if (strcmp(table, chain_table) != 0 ||
(chain && strcmp(chain, chain_name) != 0))
goto next;
/* this is a base chain */
if (nft_chain_builtin(c)) {
printf("-P %s %s", chain_name, policy_name[policy]);
if (counters) {
printf(" -c %"PRIu64" %"PRIu64"\n",
nftnl_chain_get_u64(c, NFTNL_CHAIN_PACKETS),
nftnl_chain_get_u64(c, NFTNL_CHAIN_BYTES));
} else
printf("\n");
} else {
printf("-N %s\n", chain_name);
}
next:
c = nftnl_chain_list_iter_next(iter);
}
nftnl_chain_list_iter_destroy(iter);
return 1;
}
int nft_rule_list_save(struct nft_handle *h, const char *chain,
const char *table, int rulenum, int counters)
{
struct nftnl_chain_list *list;
struct nftnl_chain_list_iter *iter;
unsigned int format = 0;
struct nftnl_chain *c;
int ret = 0;
/* If built-in chains don't exist for this table, create them */
if (nft_xtables_config_load(h, XTABLES_CONFIG_DEFAULT, 0) < 0) {
nft_xt_builtin_init(h, table);
/* Force table and chain creation, otherwise first iptables -L
* lists no table/chains.
*/
if (!list_empty(&h->obj_list)) {
nft_commit(h);
flush_chain_cache(h, NULL);
}
}
if (!nft_is_table_compatible(h, table)) {
xtables_error(OTHER_PROBLEM, "table `%s' is incompatible, use 'nft' tool.\n", table);
return 0;
}
list = nft_chain_list_get(h);
/* Dump policies and custom chains first */
if (!rulenum)
nftnl_rule_list_chain_save(h, chain, table, list, counters);
/* Now dump out rules in this table */
iter = nftnl_chain_list_iter_create(list);
if (iter == NULL)
goto err;
if (counters < 0)
format = FMT_C_COUNTS;
else if (counters == 0)
format = FMT_NOCOUNTS;
c = nftnl_chain_list_iter_next(iter);
while (c != NULL) {
const char *chain_table =
nftnl_chain_get_str(c, NFTNL_CHAIN_TABLE);
const char *chain_name =
nftnl_chain_get_str(c, NFTNL_CHAIN_NAME);
if (strcmp(table, chain_table) != 0)
goto next;
if (chain && strcmp(chain, chain_name) != 0)
goto next;
ret = __nft_rule_list(h, chain_name, table, rulenum,
format, list_save);
/* we printed the chain we wanted, stop processing. */
if (chain)
break;
next:
c = nftnl_chain_list_iter_next(iter);
}
nftnl_chain_list_iter_destroy(iter);
err:
return ret;
}
int nft_rule_zero_counters(struct nft_handle *h, const char *chain,
const char *table, int rulenum)
{
struct iptables_command_state cs = {};
struct nftnl_rule_list *list;
struct nftnl_rule *r;
int ret = 0;
nft_fn = nft_rule_delete;
list = nft_rule_list_get(h);
if (list == NULL)
return 0;
r = nft_rule_find(h, list, chain, table, NULL, rulenum);
if (r == NULL) {
errno = ENOENT;
ret = 1;
goto error;
}
nft_rule_to_iptables_command_state(r, &cs);
cs.counters.pcnt = cs.counters.bcnt = 0;
ret = nft_rule_append(h, chain, table, &cs,
nftnl_rule_get_u64(r, NFTNL_RULE_HANDLE),
false);
error:
return ret;
}
static void nft_compat_table_batch_add(struct nft_handle *h, uint16_t type,
uint16_t flags, uint32_t seq,
struct nftnl_table *table)
{
struct nlmsghdr *nlh;
nlh = nftnl_table_nlmsg_build_hdr(nftnl_batch_buffer(h->batch),
type, h->family, flags, seq);
nftnl_table_nlmsg_build_payload(nlh, table);
}
static void nft_compat_chain_batch_add(struct nft_handle *h, uint16_t type,
uint16_t flags, uint32_t seq,
struct nftnl_chain *chain)
{
struct nlmsghdr *nlh;
nlh = nftnl_chain_nlmsg_build_hdr(nftnl_batch_buffer(h->batch),
type, h->family, flags, seq);
nftnl_chain_nlmsg_build_payload(nlh, chain);
nft_chain_print_debug(chain, nlh);
}
static void nft_compat_rule_batch_add(struct nft_handle *h, uint16_t type,
uint16_t flags, uint32_t seq,
struct nftnl_rule *rule)
{
struct nlmsghdr *nlh;
nlh = nftnl_rule_nlmsg_build_hdr(nftnl_batch_buffer(h->batch),
type, h->family, flags, seq);
nftnl_rule_nlmsg_build_payload(nlh, rule);
nft_rule_print_debug(rule, nlh);
}
static void batch_obj_del(struct nft_handle *h, struct obj_update *o)
{
switch (o->type) {
case NFT_COMPAT_TABLE_ADD:
case NFT_COMPAT_TABLE_FLUSH:
nftnl_table_free(o->table);
break;
case NFT_COMPAT_CHAIN_ZERO:
case NFT_COMPAT_CHAIN_USER_ADD:
break;
case NFT_COMPAT_CHAIN_ADD:
case NFT_COMPAT_CHAIN_USER_DEL:
case NFT_COMPAT_CHAIN_USER_FLUSH:
case NFT_COMPAT_CHAIN_UPDATE:
case NFT_COMPAT_CHAIN_RENAME:
nftnl_chain_free(o->chain);
break;
case NFT_COMPAT_RULE_APPEND:
case NFT_COMPAT_RULE_INSERT:
case NFT_COMPAT_RULE_REPLACE:
case NFT_COMPAT_RULE_DELETE:
break;
case NFT_COMPAT_RULE_FLUSH:
nftnl_rule_free(o->rule);
break;
}
h->obj_list_num--;
list_del(&o->head);
free(o);
}
static int nft_action(struct nft_handle *h, int action)
{
struct obj_update *n, *tmp;
struct mnl_err *err, *ne;
unsigned int buflen, i, len;
bool show_errors = true;
char errmsg[1024];
uint32_t seq = 1;
int ret = 0;
h->batch = mnl_batch_init();
mnl_batch_begin(h->batch, seq++);
list_for_each_entry(n, &h->obj_list, head) {
n->seq = seq++;
switch (n->type) {
case NFT_COMPAT_TABLE_ADD:
nft_compat_table_batch_add(h, NFT_MSG_NEWTABLE,
NLM_F_CREATE, n->seq,
n->table);
break;
case NFT_COMPAT_TABLE_FLUSH:
nft_compat_table_batch_add(h, NFT_MSG_DELTABLE,
0,
n->seq, n->table);
break;
case NFT_COMPAT_CHAIN_ADD:
case NFT_COMPAT_CHAIN_ZERO:
nft_compat_chain_batch_add(h, NFT_MSG_NEWCHAIN,
NLM_F_CREATE, n->seq,
n->chain);
break;
case NFT_COMPAT_CHAIN_USER_ADD:
nft_compat_chain_batch_add(h, NFT_MSG_NEWCHAIN,
NLM_F_EXCL, n->seq,
n->chain);
break;
case NFT_COMPAT_CHAIN_USER_DEL:
nft_compat_chain_batch_add(h, NFT_MSG_DELCHAIN,
NLM_F_NONREC, n->seq,
n->chain);
break;
case NFT_COMPAT_CHAIN_USER_FLUSH:
nft_compat_chain_batch_add(h, NFT_MSG_DELCHAIN,
0, n->seq,
n->chain);
break;
case NFT_COMPAT_CHAIN_UPDATE:
nft_compat_chain_batch_add(h, NFT_MSG_NEWCHAIN,
h->restore ?
NLM_F_CREATE : 0,
n->seq, n->chain);
break;
case NFT_COMPAT_CHAIN_RENAME:
nft_compat_chain_batch_add(h, NFT_MSG_NEWCHAIN, 0,
n->seq, n->chain);
break;
case NFT_COMPAT_RULE_APPEND:
nft_compat_rule_batch_add(h, NFT_MSG_NEWRULE,
NLM_F_CREATE | NLM_F_APPEND,
n->seq, n->rule);
break;
case NFT_COMPAT_RULE_INSERT:
nft_compat_rule_batch_add(h, NFT_MSG_NEWRULE,
NLM_F_CREATE, n->seq,
n->rule);
break;
case NFT_COMPAT_RULE_REPLACE:
nft_compat_rule_batch_add(h, NFT_MSG_NEWRULE,
NLM_F_CREATE | NLM_F_REPLACE,
n->seq, n->rule);
break;
case NFT_COMPAT_RULE_DELETE:
case NFT_COMPAT_RULE_FLUSH:
nft_compat_rule_batch_add(h, NFT_MSG_DELRULE, 0,
n->seq, n->rule);
break;
}
mnl_nft_batch_continue(h->batch);
}
switch (action) {
case NFT_COMPAT_COMMIT:
mnl_batch_end(h->batch, seq++);
break;
case NFT_COMPAT_ABORT:
break;
}
ret = mnl_batch_talk(h->nl, h->batch, &h->err_list);
i = 0;
buflen = sizeof(errmsg);
list_for_each_entry_safe(n, tmp, &h->obj_list, head) {
list_for_each_entry_safe(err, ne, &h->err_list, head) {
if (err->seqnum > n->seq)
break;
if (err->seqnum == n->seq && show_errors) {
if (n->error.lineno == 0)
show_errors = false;
len = mnl_append_error(h, n, err, errmsg + i, buflen);
if (len > 0 && len <= buflen) {
buflen -= len;
i += len;
}
}
mnl_err_list_free(err);
}
batch_obj_del(h, n);
}
mnl_batch_reset(h->batch);
if (i)
xtables_error(RESOURCE_PROBLEM, "%s", errmsg);
return ret == 0 ? 1 : 0;
}
int nft_commit(struct nft_handle *h)
{
return nft_action(h, NFT_COMPAT_COMMIT);
}
int nft_abort(struct nft_handle *h)
{
return nft_action(h, NFT_COMPAT_ABORT);
}
int nft_compatible_revision(const char *name, uint8_t rev, int opt)
{
struct mnl_socket *nl;
char buf[16536];
struct nlmsghdr *nlh;
uint32_t portid, seq, type = 0;
uint32_t pf = AF_INET;
int ret = 0;
switch (opt) {
case IPT_SO_GET_REVISION_MATCH:
break;
case IP6T_SO_GET_REVISION_MATCH:
pf = AF_INET6;
break;
case IPT_SO_GET_REVISION_TARGET:
type = 1;
break;
case IP6T_SO_GET_REVISION_TARGET:
type = 1;
pf = AF_INET6;
break;
default:
/* No revision support (arp, ebtables), assume latest version ok */
return 1;
}
nlh = mnl_nlmsg_put_header(buf);
nlh->nlmsg_type = (NFNL_SUBSYS_NFT_COMPAT << 8) | NFNL_MSG_COMPAT_GET;
nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
nlh->nlmsg_seq = seq = time(NULL);
struct nfgenmsg *nfg = mnl_nlmsg_put_extra_header(nlh, sizeof(*nfg));
nfg->nfgen_family = pf;
nfg->version = NFNETLINK_V0;
nfg->res_id = 0;
mnl_attr_put_strz(nlh, NFTA_COMPAT_NAME, name);
mnl_attr_put_u32(nlh, NFTA_COMPAT_REV, htonl(rev));
mnl_attr_put_u32(nlh, NFTA_COMPAT_TYPE, htonl(type));
DEBUGP("requesting `%s' rev=%d type=%d via nft_compat\n",
name, rev, type);
nl = mnl_socket_open(NETLINK_NETFILTER);
if (nl == NULL)
return 0;
if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0)
goto err;
portid = mnl_socket_get_portid(nl);
if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0)
goto err;
ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
if (ret == -1)
goto err;
ret = mnl_cb_run(buf, ret, seq, portid, NULL, NULL);
if (ret == -1)
goto err;
err:
mnl_socket_close(nl);
return ret < 0 ? 0 : 1;
}
/* Translates errno numbers into more human-readable form than strerror. */
const char *nft_strerror(int err)
{
unsigned int i;
static struct table_struct {
void *fn;
int err;
const char *message;
} table[] =
{
{ nft_chain_user_del, ENOTEMPTY, "Chain is not empty" },
{ nft_chain_user_del, EINVAL, "Can't delete built-in chain" },
{ nft_chain_user_del, EBUSY, "Directory not empty" },
{ nft_chain_user_del, EMLINK,
"Can't delete chain with references left" },
{ nft_chain_user_add, EEXIST, "Chain already exists" },
{ nft_rule_insert, ENOENT, "Index of insertion too big" },
{ nft_rule_check, ENOENT, "Bad rule (does a matching rule exist in that chain?)" },
{ nft_rule_replace, ENOENT, "Index of replacement too big" },
{ nft_rule_delete_num, ENOENT, "Index of deletion too big" },
/* { TC_READ_COUNTER, E2BIG, "Index of counter too big" },
{ TC_ZERO_COUNTER, E2BIG, "Index of counter too big" }, */
/* ENOENT for DELETE probably means no matching rule */
{ nft_rule_delete, ENOENT,
"Bad rule (does a matching rule exist in that chain?)" },
{ nft_chain_set, ENOENT, "Bad built-in chain name" },
{ nft_chain_set, EINVAL, "Bad policy name" },
{ nft_chain_set, ENXIO, "Bad table name" },
{ NULL, ELOOP, "Loop found in table" },
{ NULL, EPERM, "Permission denied (you must be root)" },
{ NULL, 0, "Incompatible with this kernel" },
{ NULL, ENOPROTOOPT, "iptables who? (do you need to insmod?)" },
{ NULL, ENOSYS, "Will be implemented real soon. I promise ;)" },
{ NULL, ENOMEM, "Memory allocation problem" },
{ NULL, ENOENT, "No chain/target/match by that name" },
};
for (i = 0; i < sizeof(table)/sizeof(struct table_struct); i++) {
if ((!table[i].fn || table[i].fn == nft_fn)
&& table[i].err == err)
return table[i].message;
}
return strerror(err);
}
static void xtables_config_perror(uint32_t flags, const char *fmt, ...)
{
va_list args;
va_start(args, fmt);
if (flags & NFT_LOAD_VERBOSE)
vfprintf(stderr, fmt, args);
va_end(args);
}
static int __nft_xtables_config_load(struct nft_handle *h, const char *filename,
uint32_t flags)
{
struct nftnl_table_list *table_list = NULL;
struct nftnl_chain_list *chain_list = NULL;
struct nftnl_table_list_iter *titer = NULL;
struct nftnl_chain_list_iter *citer = NULL;
struct nftnl_table *table;
struct nftnl_chain *chain;
uint32_t table_family, chain_family;
bool found = false;
table_list = nftnl_table_list_alloc();
chain_list = nftnl_chain_list_alloc();
if (xtables_config_parse(filename, table_list, chain_list) < 0) {
if (errno == ENOENT) {
xtables_config_perror(flags,
"configuration file `%s' does not exists\n",
filename);
} else {
xtables_config_perror(flags,
"Fatal error parsing config file: %s\n",
strerror(errno));
}
goto err;
}
/* Stage 1) create tables */
titer = nftnl_table_list_iter_create(table_list);
while ((table = nftnl_table_list_iter_next(titer)) != NULL) {
table_family = nftnl_table_get_u32(table,
NFTNL_TABLE_FAMILY);
if (h->family != table_family)
continue;
found = true;
if (batch_table_add(h, NFT_COMPAT_TABLE_ADD, table) < 0) {
if (errno == EEXIST) {
xtables_config_perror(flags,
"table `%s' already exists, skipping\n",
(char *)nftnl_table_get(table, NFTNL_TABLE_NAME));
} else {
xtables_config_perror(flags,
"table `%s' cannot be create, reason `%s'. Exitting\n",
(char *)nftnl_table_get(table, NFTNL_TABLE_NAME),
strerror(errno));
goto err;
}
continue;
}
xtables_config_perror(flags, "table `%s' has been created\n",
(char *)nftnl_table_get(table, NFTNL_TABLE_NAME));
}
nftnl_table_list_iter_destroy(titer);
nftnl_table_list_free(table_list);
if (!found)
goto err;
/* Stage 2) create chains */
citer = nftnl_chain_list_iter_create(chain_list);
while ((chain = nftnl_chain_list_iter_next(citer)) != NULL) {
chain_family = nftnl_chain_get_u32(chain,
NFTNL_CHAIN_TABLE);
if (h->family != chain_family)
continue;
if (batch_chain_add(h, NFT_COMPAT_CHAIN_ADD, chain) < 0) {
if (errno == EEXIST) {
xtables_config_perror(flags,
"chain `%s' already exists in table `%s', skipping\n",
(char *)nftnl_chain_get(chain, NFTNL_CHAIN_NAME),
(char *)nftnl_chain_get(chain, NFTNL_CHAIN_TABLE));
} else {
xtables_config_perror(flags,
"chain `%s' cannot be create, reason `%s'. Exitting\n",
(char *)nftnl_chain_get(chain, NFTNL_CHAIN_NAME),
strerror(errno));
goto err;
}
continue;
}
xtables_config_perror(flags,
"chain `%s' in table `%s' has been created\n",
(char *)nftnl_chain_get(chain, NFTNL_CHAIN_NAME),
(char *)nftnl_chain_get(chain, NFTNL_CHAIN_TABLE));
}
nftnl_chain_list_iter_destroy(citer);
nftnl_chain_list_free(chain_list);
h->config_done = 1;
return 0;
err:
nftnl_table_list_free(table_list);
nftnl_chain_list_free(chain_list);
if (titer != NULL)
nftnl_table_list_iter_destroy(titer);
if (citer != NULL)
nftnl_chain_list_iter_destroy(citer);
h->config_done = -1;
return -1;
}
int nft_xtables_config_load(struct nft_handle *h, const char *filename,
uint32_t flags)
{
if (!h->config_done)
return __nft_xtables_config_load(h, filename, flags);
return h->config_done;
}
static void nft_chain_zero_rule_counters(struct nft_handle *h,
struct nftnl_chain *c)
{
struct nftnl_rule_list_iter *iter;
struct nftnl_rule_list *list;
const char *table_name;
const char *chain_name;
struct nftnl_rule *r;
list = nft_rule_list_get(h);
if (list == NULL)
return;
iter = nftnl_rule_list_iter_create(list);
if (iter == NULL)
return;
table_name = nftnl_chain_get_str(c, NFTNL_CHAIN_TABLE);
chain_name = nftnl_chain_get_str(c, NFTNL_CHAIN_NAME);
r = nftnl_rule_list_iter_next(iter);
while (r != NULL) {
struct nftnl_expr_iter *ei;
const char *table_chain;
const char *rule_chain;
struct nftnl_expr *e;
bool zero_needed;
table_chain = nftnl_rule_get_str(r, NFTNL_RULE_TABLE);
if (strcmp(table_chain, table_name))
goto next;
rule_chain = nftnl_rule_get_str(r, NFTNL_RULE_CHAIN);
if (strcmp(rule_chain, chain_name))
goto next;
ei = nftnl_expr_iter_create(r);
if (!ei)
break;
e = nftnl_expr_iter_next(ei);
zero_needed = false;
while (e != NULL) {
const char *en = nftnl_expr_get_str(e, NFTNL_EXPR_NAME);
if (strcmp(en, "counter") == 0 && (
nftnl_expr_get_u64(e, NFTNL_EXPR_CTR_PACKETS) ||
nftnl_expr_get_u64(e, NFTNL_EXPR_CTR_BYTES))) {
nftnl_expr_set_u64(e, NFTNL_EXPR_CTR_PACKETS, 0);
nftnl_expr_set_u64(e, NFTNL_EXPR_CTR_BYTES, 0);
zero_needed = true;
}
e = nftnl_expr_iter_next(ei);
}
nftnl_expr_iter_destroy(ei);
if (zero_needed) {
/*
* Unset RULE_POSITION for older kernels, we want to replace
* rule based on its handle only.
*/
nftnl_rule_unset(r, NFTNL_RULE_POSITION);
batch_rule_add(h, NFT_COMPAT_RULE_REPLACE, r);
}
next:
r = nftnl_rule_list_iter_next(iter);
}
nftnl_rule_list_iter_destroy(iter);
}
int nft_chain_zero_counters(struct nft_handle *h, const char *chain,
const char *table, bool verbose)
{
struct nftnl_chain_list *list;
struct nftnl_chain_list_iter *iter;
struct nftnl_chain *c;
int ret = 0;
list = nft_chain_list_get(h);
if (list == NULL)
goto err;
iter = nftnl_chain_list_iter_create(list);
if (iter == NULL)
goto err;
c = nftnl_chain_list_iter_next(iter);
while (c != NULL) {
const char *chain_name =
nftnl_chain_get(c, NFTNL_CHAIN_NAME);
const char *chain_table =
nftnl_chain_get(c, NFTNL_CHAIN_TABLE);
if (strcmp(table, chain_table) != 0)
goto next;
if (chain != NULL && strcmp(chain, chain_name) != 0)
goto next;
if (verbose)
fprintf(stdout, "Zeroing chain `%s'\n", chain_name);
if (nftnl_chain_is_set(c, NFTNL_CHAIN_HOOKNUM)) {
/* zero base chain counters. */
nftnl_chain_set_u64(c, NFTNL_CHAIN_PACKETS, 0);
nftnl_chain_set_u64(c, NFTNL_CHAIN_BYTES, 0);
}
nft_chain_zero_rule_counters(h, c);
nftnl_chain_unset(c, NFTNL_CHAIN_HANDLE);
ret = batch_chain_add(h, NFT_COMPAT_CHAIN_ZERO, c);
if (chain != NULL)
break;
next:
c = nftnl_chain_list_iter_next(iter);
}
nftnl_chain_list_iter_destroy(iter);
err:
/* the core expects 1 for success and 0 for error */
return ret == 0 ? 1 : 0;
}
uint32_t nft_invflags2cmp(uint32_t invflags, uint32_t flag)
{
if (invflags & flag)
return NFT_CMP_NEQ;
return NFT_CMP_EQ;
}
#define NFT_COMPAT_EXPR_MAX 8
static const char *supported_exprs[NFT_COMPAT_EXPR_MAX] = {
"match",
"target",
"payload",
"meta",
"cmp",
"bitwise",
"counter",
"immediate"
};
static int nft_is_expr_compatible(const struct nftnl_expr *expr)
{
const char *name = nftnl_expr_get_str(expr, NFTNL_EXPR_NAME);
int i;
for (i = 0; i < NFT_COMPAT_EXPR_MAX; i++) {
if (strcmp(supported_exprs[i], name) == 0)
return 0;
}
if (!strcmp(name, "limit") &&
nftnl_expr_get_u32(expr, NFTNL_EXPR_LIMIT_TYPE) == NFT_LIMIT_PKTS &&
nftnl_expr_get_u32(expr, NFTNL_EXPR_LIMIT_FLAGS) == 0)
return 0;
return 1;
}
static bool nft_is_rule_compatible(struct nftnl_rule *rule)
{
struct nftnl_expr_iter *iter;
struct nftnl_expr *expr;
bool compatible = false;
iter = nftnl_expr_iter_create(rule);
if (iter == NULL)
return false;
expr = nftnl_expr_iter_next(iter);
while (expr != NULL) {
if (nft_is_expr_compatible(expr) == 0) {
expr = nftnl_expr_iter_next(iter);
continue;
}
compatible = true;
break;
}
nftnl_expr_iter_destroy(iter);
return compatible;
}
static int nft_is_chain_compatible(const struct nft_handle *h,
const struct nftnl_chain *chain)
{
const char *table, *name, *type, *cur_table;
struct builtin_chain *chains;
int i, j, prio;
enum nf_inet_hooks hook;
table = nftnl_chain_get(chain, NFTNL_CHAIN_TABLE);
name = nftnl_chain_get(chain, NFTNL_CHAIN_NAME);
type = nftnl_chain_get(chain, NFTNL_CHAIN_TYPE);
prio = nftnl_chain_get_u32(chain, NFTNL_CHAIN_PRIO);
hook = nftnl_chain_get_u32(chain, NFTNL_CHAIN_HOOKNUM);
for (i = 0; i < NFT_TABLE_MAX; i++) {
cur_table = h->tables[i].name;
chains = h->tables[i].chains;
if (!cur_table || strcmp(table, cur_table) != 0)
continue;
for (j = 0; j < NF_INET_NUMHOOKS && chains[j].name; j++) {
if (strcmp(name, chains[j].name) != 0)
continue;
if (strcmp(type, chains[j].type) == 0 &&
prio == chains[j].prio &&
hook == chains[j].hook)
return 0;
break;
}
}
return 1;
}
static int nft_are_chains_compatible(struct nft_handle *h, const char *tablename)
{
struct nftnl_chain_list *list;
struct nftnl_chain_list_iter *iter;
struct nftnl_chain *chain;
int ret = 0;
list = nft_chain_list_get(h);
if (list == NULL)
return -1;
iter = nftnl_chain_list_iter_create(list);
if (iter == NULL)
return -1;
chain = nftnl_chain_list_iter_next(iter);
while (chain != NULL) {
const char *chain_table;
chain_table = nftnl_chain_get_str(chain, NFTNL_CHAIN_TABLE);
if (strcmp(chain_table, tablename) ||
!nft_chain_builtin(chain))
goto next;
ret = nft_is_chain_compatible(h, chain);
if (ret != 0)
break;
next:
chain = nftnl_chain_list_iter_next(iter);
}
nftnl_chain_list_iter_destroy(iter);
return ret;
}
bool nft_is_table_compatible(struct nft_handle *h, const char *tablename)
{
struct nftnl_rule_list *list;
struct nftnl_rule_list_iter *iter;
struct nftnl_rule *rule;
int ret = 0;
if (!nft_table_builtin_find(h, tablename))
return false;
ret = nft_are_chains_compatible(h, tablename);
if (ret != 0)
return false;
list = nft_rule_list_get(h);
if (list == NULL)
return true;
iter = nftnl_rule_list_iter_create(list);
if (iter == NULL)
return true;
rule = nftnl_rule_list_iter_next(iter);
while (rule != NULL) {
const char *table = nftnl_rule_get_str(rule, NFTNL_RULE_TABLE);
if (strcmp(table, tablename))
goto next_rule;
ret = nft_is_rule_compatible(rule);
if (ret != 0)
break;
next_rule:
rule = nftnl_rule_list_iter_next(iter);
}
nftnl_rule_list_iter_destroy(iter);
return ret == 0;
}