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natcap_common.c
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/*
* Author: Chen Minqiang <[email protected]>
* Date : Sun, 05 Jun 2016 16:27:20 +0800
*
* This file is part of the natcap.
*
* natcap 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 3 of the License, or
* (at your option) any later version.
*
* natcap 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 natcap; see the file COPYING. If not, see
* <http://www.gnu.org/licenses/>.
*/
#include <linux/module.h>
#include <linux/version.h>
#include <linux/mman.h>
#include <linux/spinlock.h>
#include <linux/rcupdate.h>
#include <linux/highmem.h>
#include <linux/udp.h>
#include <linux/netfilter.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack_zones.h>
#include <net/netfilter/nf_conntrack_extend.h>
#include <net/netfilter/nf_conntrack_seqadj.h>
#include <net/netfilter/nf_nat.h>
#include <linux/netfilter/ipset/ip_set.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_set.h>
#include "natcap_common.h"
#include "natcap_client.h"
#include "natcap_server.h"
#include "natcap_knock.h"
#include "natcap_peer.h"
unsigned short natmap_start = 0;
unsigned short natmap_end = 0;
__be32 *natmap_dip = NULL;
unsigned short natcap_udp_seq_lock = 0;
unsigned short natcap_ignore_forward = 0;
unsigned int natcap_ignore_mask = 0x00000000;
unsigned int natcap_max_pmtu = 1420;
unsigned int natcap_touch_timeout = 32;
unsigned short natcap_redirect_port = 0;
unsigned short natcap_client_redirect_port = 0;
unsigned int disabled = 1;
unsigned long long flow_total_tx_bytes = 0;
unsigned long long flow_total_rx_bytes = 0;
unsigned int debug = 0;
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "Debug level (0=none,1=error,2=warn,4=info,8=debug,16=fixme,...,31=all) default=0");
unsigned int mode = MIXING_MODE;
module_param(mode, int, 0);
MODULE_PARM_DESC(mode, "Working mode (0=client,1=server,2=forward,3=client+server) default=0");
unsigned int auth_enabled = 0;
module_param(auth_enabled, int, 0);
MODULE_PARM_DESC(auth_enabled, "Disable auth default=0");
unsigned int server_seed = 0;
module_param(server_seed, int, 0);
MODULE_PARM_DESC(server_seed, "Server side seed number for encode");
char htp_confusion_host[64] = "bing.com";
char htp_confusion_req[1024] = ""
"GET /00000000 HTTP/1.1\r\n"
"Host: bing.com\r\n"
"Connection: keep-alive\r\n"
"Pragma: no-cache\r\n"
"Cache-Control: no-cache\r\n"
"User-Agent: Mozilla/5.0 (X11; Linux x86_64)\r\n"
"Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8\r\n"
"Accept-Encoding: gzip, deflate, sdch\r\n"
"Accept-Language: zh-CN,en-US;q=0.8,en;q=0.6,zh;q=0.4\r\n"
"\r\n";
char htp_confusion_rsp[1024] = ""
"HTTP/1.1 200 OK\r\n"
"Content-Type: text/html;charset=ISO-8859-1\r\n"
"Content-Length: 4294967295\r\n"
"Connection: keep-alive\r\n"
"\r\n";
const char *const mode_str[] = {
[CLIENT_MODE] = "CLIENT",
[SERVER_MODE] = "SERVER",
[MIXING_MODE] = "CLIENT+SERVER",
[KNOCK_MODE] = "KNOCK",
[PEER_MODE] = "PEER",
};
const char *const hooknames[] = {
[NF_INET_PRE_ROUTING] = "PRE",
[NF_INET_LOCAL_IN] = "IN",
[NF_INET_FORWARD] = "FD",
[NF_INET_LOCAL_OUT] = "OUT",
[NF_INET_POST_ROUTING] = "POST",
};
static unsigned char natcap_map[256] = {
152, 151, 106, 224, 13, 90, 137, 200, 178, 138, 212, 156, 238, 54, 44, 237,
101, 42, 97, 91, 163, 191, 119, 157, 123, 102, 124, 125, 197, 35, 15, 26,
40, 179, 129, 229, 38, 221, 71, 175, 95, 77, 245, 153, 31, 56, 253, 107,
109, 243, 67, 225, 167, 133, 19, 32, 150, 180, 160, 203, 110, 131, 169, 16,
130, 210, 183, 24, 12, 79, 114, 118, 215, 250, 10, 165, 164, 27, 112, 233,
213, 49, 204, 139, 65, 98, 34, 115, 173, 228, 207, 47, 59, 143, 135, 219,
199, 66, 76, 113, 33, 186, 187, 134, 105, 155, 190, 249, 181, 21, 201, 88,
9, 70, 89, 62, 241, 220, 236, 148, 227, 116, 214, 41, 185, 244, 211, 184,
166, 18, 140, 63, 3, 222, 136, 248, 84, 93, 121, 120, 132, 171, 108, 73,
55, 30, 83, 1, 68, 117, 128, 87, 209, 231, 239, 5, 223, 172, 17, 246,
39, 254, 170, 94, 48, 182, 196, 58, 149, 86, 216, 22, 202, 20, 159, 53,
78, 174, 141, 189, 252, 4, 25, 69, 8, 64, 147, 37, 60, 111, 74, 11,
192, 146, 198, 255, 240, 61, 36, 51, 247, 226, 57, 154, 194, 6, 80, 50,
208, 72, 144, 234, 158, 217, 23, 82, 242, 122, 195, 177, 193, 205, 7, 232,
96, 206, 145, 103, 43, 45, 162, 176, 104, 126, 100, 188, 81, 218, 161, 92,
46, 251, 52, 75, 0, 142, 28, 14, 2, 168, 235, 127, 230, 85, 99, 29,
};
static unsigned char dnatcap_map[256];
static void dnatcap_map_init(void)
{
int i;
for (i = 0; i < 256; i++) {
natcap_map[i] = (natcap_map[i] + server_seed) & 0xff;
}
for (i = 0; i < 256; i++) {
dnatcap_map[natcap_map[i]] = i;
}
}
void natcap_data_encode(unsigned char *buf, int len)
{
int i;
for (i = 0; i < len; i++) {
buf[i] = natcap_map[buf[i]];
}
}
void natcap_data_decode(unsigned char *buf, int len)
{
int i;
for (i = 0; i < len; i++) {
buf[i] = dnatcap_map[buf[i]];
}
}
void skb_data_hook(struct sk_buff *skb, int offset, int len, void (*update)(unsigned char *, int))
{
int start = skb_headlen(skb);
int i, copy = start - offset;
struct sk_buff *frag_iter;
int pos = 0;
if (copy > 0) {
if (copy > len)
copy = len;
update(skb->data + offset, copy);
if ((len -= copy) == 0)
return;
offset += copy;
pos = copy;
}
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
int end;
skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
WARN_ON(start > offset + len);
end = start + skb_frag_size(frag);
if ((copy = end - offset) > 0) {
#if defined(skb_frag_foreach_page)
u32 p_off, p_len, copied;
struct page *p;
u8 *vaddr;
if (copy > len)
copy = len;
skb_frag_foreach_page(frag,
skb_frag_off(frag) + offset - start,
copy, p, p_off, p_len, copied) {
vaddr = kmap_atomic(p);
update(vaddr + p_off, p_len);
kunmap_atomic(vaddr);
pos += p_len;
}
if (!(len -= copy))
return;
offset += copy;
#else
u8 *vaddr;
if (copy > len)
copy = len;
vaddr = kmap_atomic(skb_frag_page(frag));
update(vaddr + frag->page_offset + offset - start, copy);
kunmap_atomic(vaddr);
if (!(len -= copy))
return;
offset += copy;
pos += copy;
#endif
}
start = end;
}
skb_walk_frags(skb, frag_iter) {
int end;
WARN_ON(start > offset + len);
end = start + frag_iter->len;
if ((copy = end - offset) > 0) {
if (copy > len)
copy = len;
skb_data_hook(frag_iter, offset - start, copy, update);
if ((len -= copy) == 0)
return;
offset += copy;
pos += copy;
}
start = end;
}
BUG_ON(len);
return;
}
int skb_rcsum_verify(struct sk_buff *skb)
{
struct iphdr *iph = ip_hdr(skb);
int len = ntohs(iph->tot_len);
int ret = 0;
__sum16 l3_sum, l4_sum;
__wsum skbcsum;
if (skb->len < len) {
return -1;
} else if (len < (iph->ihl * 4)) {
return -1;
}
if (iph->protocol == IPPROTO_TCP) {
struct tcphdr *tcph = (struct tcphdr *)((void *)iph + iph->ihl*4);
l3_sum = iph->check;
l4_sum = tcph->check;
iph->check = 0;
iph->check = ip_fast_csum(iph, iph->ihl);
if (l3_sum != iph->check) {
iph->check = l3_sum;
return -1;
}
tcph->check = 0;
skbcsum = skb_checksum(skb, iph->ihl * 4, len - iph->ihl * 4, 0);
tcph->check = csum_tcpudp_magic(iph->saddr, iph->daddr, len - iph->ihl * 4, iph->protocol, skbcsum);
if (l4_sum != tcph->check) {
tcph->check = l4_sum;
return -1;
}
} else if (iph->protocol == IPPROTO_UDP) {
struct udphdr *udph = (struct udphdr *)((void *)iph + iph->ihl*4);
l3_sum = iph->check;
l4_sum = udph->check;
iph->check = 0;
iph->check = ip_fast_csum(iph, iph->ihl);
if (l3_sum != iph->check) {
iph->check = l3_sum;
return -1;
}
if (udph->check != 0) {
udph->check = 0;
skbcsum = skb_checksum(skb, iph->ihl * 4, len - iph->ihl * 4, 0);
udph->check = csum_tcpudp_magic(iph->saddr, iph->daddr, len - iph->ihl * 4, iph->protocol, skbcsum);
if (udph->check == 0)
udph->check = CSUM_MANGLED_0;
if (l4_sum != udph->check) {
udph->check = l4_sum;
return -1;
}
}
} else {
return -1;
}
return ret;
}
int skb_rcsum_tcpudp(struct sk_buff *skb)
{
struct iphdr *iph = ip_hdr(skb);
int len = ntohs(iph->tot_len);
__wsum skbcsum;
if (skb->len < len) {
return -1;
} else if (len < (iph->ihl * 4)) {
return -1;
}
if (iph->protocol == IPPROTO_TCP) {
struct tcphdr *tcph = (struct tcphdr *)((void *)iph + iph->ihl*4);
if (skb->ip_summed == CHECKSUM_PARTIAL) {
iph->check = 0;
iph->check = ip_fast_csum(iph, iph->ihl);
tcph->check = 0;
tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len - iph->ihl * 4, IPPROTO_TCP, 0);
skb->csum_start = (unsigned char *)tcph - skb->head;
skb->csum_offset = offsetof(struct tcphdr, check);
} else {
iph->check = 0;
iph->check = ip_fast_csum(iph, iph->ihl);
tcph->check = 0;
skbcsum = skb_checksum(skb, iph->ihl * 4, len - iph->ihl * 4, 0);
tcph->check = csum_tcpudp_magic(iph->saddr, iph->daddr, len - iph->ihl * 4, iph->protocol, skbcsum);
if (skb->ip_summed == CHECKSUM_COMPLETE) {
skb->ip_summed = CHECKSUM_UNNECESSARY;
}
}
} else if (iph->protocol == IPPROTO_UDP) {
struct udphdr *udph = (struct udphdr *)((void *)iph + iph->ihl*4);
if (skb->ip_summed == CHECKSUM_PARTIAL) {
iph->check = 0;
iph->check = ip_fast_csum(iph, iph->ihl);
udph->check = 0;
udph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len - iph->ihl * 4, IPPROTO_UDP, 0);
skb->csum_start = (unsigned char *)udph - skb->head;
skb->csum_offset = offsetof(struct udphdr, check);
} else {
iph->check = 0;
iph->check = ip_fast_csum(iph, iph->ihl);
if (udph->check) {
udph->check = 0;
skbcsum = skb_checksum(skb, iph->ihl * 4, len - iph->ihl * 4, 0);
udph->check = csum_tcpudp_magic(iph->saddr, iph->daddr, len - iph->ihl * 4, iph->protocol, skbcsum);
if (udph->check == 0)
udph->check = CSUM_MANGLED_0;
}
if (skb->ip_summed == CHECKSUM_COMPLETE) {
skb->ip_summed = CHECKSUM_UNNECESSARY;
}
}
} else {
return -1;
}
return 0;
}
int natcap_tcpopt_setup(unsigned long status, struct sk_buff *skb, struct nf_conn *ct, struct natcap_TCPOPT *tcpopt, __be32 ip, __be16 port)
{
int size;
struct iphdr *iph = ip_hdr(skb);
struct tcphdr *tcph = (struct tcphdr *)((void *)iph + iph->ihl * 4);
struct natcap_session *ns = natcap_session_get(ct);
if (NULL == ns) {
return -1;
}
tcpopt->header.subtype = 0;
if ((status & NATCAP_NEED_ENC))
tcpopt->header.encryption = 1;
else
tcpopt->header.encryption = 0;
if ((status & NATCAP_CLIENT_MODE)) {
int add_len = 0;
//not syn
if (!(tcph->syn && !tcph->ack)) {
if ((NS_NATCAP_AUTH & ns->n.status)) {
tcpopt->header.type = NATCAP_TCPOPT_TYPE_NONE;
tcpopt->header.opsize = 0;
return 0;
}
size = ALIGN(sizeof(struct natcap_TCPOPT_header) + sizeof(struct natcap_TCPOPT_user), sizeof(unsigned int));
if (tcph->doff * 4 + size <= 60) {
tcpopt->header.type = NATCAP_TCPOPT_TYPE_USER;
tcpopt->header.opcode = TCPOPT_NATCAP;
tcpopt->header.opsize = size;
memcpy(tcpopt->user.data.mac_addr, default_mac_addr, ETH_ALEN);
tcpopt->user.data.u_hash = default_u_hash;
short_set_bit(NS_NATCAP_AUTH_BIT, &ns->n.status);
return 0;
}
tcpopt->header.type = NATCAP_TCPOPT_TYPE_NONE;
tcpopt->header.opsize = 0;
return 0;
}
//syn
if (http_confusion && ns && !(NS_NATCAP_TCPUDPENC & ns->n.status) && (NS_NATCAP_ENC & ns->n.status)) {
add_len += sizeof(unsigned int);
if (ns->n.tcp_seq_offset == 0) {
ns->n.tcp_seq_offset = sizeof(htp_confusion_req) / 2 + jiffies % (sizeof(htp_confusion_req) / 4);
}
}
size = ALIGN(sizeof(struct natcap_TCPOPT_header) + sizeof(struct natcap_TCPOPT_data) + add_len, sizeof(unsigned int));
if (tcph->doff * 4 + size <= 60)
{
tcpopt->header.type = NATCAP_TCPOPT_TYPE_ALL;
tcpopt->header.opcode = TCPOPT_NATCAP;
tcpopt->header.opsize = size;
tcpopt->all.data.ip = ip;
tcpopt->all.data.port = port;
memcpy(tcpopt->all.data.mac_addr, default_mac_addr, ETH_ALEN);
tcpopt->all.data.u_hash = default_u_hash;
if (add_len == sizeof(unsigned int)) {
set_byte4((unsigned char *)tcpopt + size - add_len, htonl(ns->n.tcp_seq_offset));
tcpopt->header.type |= NATCAP_TCPOPT_CONFUSION;
}
short_set_bit(NS_NATCAP_AUTH_BIT, &ns->n.status);
if (iph->daddr == ip && knock_flood) {
tcpopt->all.data.ip = PEER_XSYN_MASK_ADDR;
}
return 0;
}
if (user_mark_natcap_mask != 0) {
/* we need u_hash in first packet */
return -1;
}
size = ALIGN(sizeof(struct natcap_TCPOPT_header) + sizeof(struct natcap_TCPOPT_dst) + add_len, sizeof(unsigned int));
if (tcph->doff * 4 + size <= 60) {
tcpopt->header.type = NATCAP_TCPOPT_TYPE_DST;
tcpopt->header.opcode = TCPOPT_NATCAP;
tcpopt->header.opsize = size;
tcpopt->dst.data.ip = ip;
tcpopt->dst.data.port = port;
if (add_len == sizeof(unsigned int)) {
set_byte4((unsigned char *)tcpopt + size - add_len, htonl(ns->n.tcp_seq_offset));
tcpopt->header.type |= NATCAP_TCPOPT_CONFUSION;
}
if (iph->daddr == ip && knock_flood) {
tcpopt->dst.data.ip = PEER_XSYN_MASK_ADDR;
}
return 0;
}
return -1;
} else {
if (ns && (NS_NATCAP_CONFUSION & ns->n.status)) {
int add_len = 0;
if (tcph->syn && tcph->ack) {
add_len += sizeof(unsigned int);
if (ns->n.tcp_ack_offset == 0) {
ns->n.tcp_ack_offset = sizeof(htp_confusion_rsp) / 4 + jiffies % (sizeof(htp_confusion_rsp) / 8);
}
size = ALIGN(sizeof(struct natcap_TCPOPT_header) + add_len, sizeof(unsigned int));
tcpopt->header.type = NATCAP_TCPOPT_TYPE_ADD;
tcpopt->header.opcode = TCPOPT_NATCAP;
tcpopt->header.opsize = size;
if (add_len == sizeof(unsigned int)) {
set_byte4((unsigned char *)tcpopt + size - add_len, htonl(ns->n.tcp_ack_offset));
tcpopt->header.type |= NATCAP_TCPOPT_CONFUSION;
}
return 0;
}
}
tcpopt->header.type = NATCAP_TCPOPT_TYPE_NONE;
tcpopt->header.opsize = 0;
return 0;
}
}
int natcap_tcp_encode(struct nf_conn *ct, struct sk_buff *skb, const struct natcap_TCPOPT *tcpopt, int dir)
{
struct iphdr *iph;
struct tcphdr *tcph;
int offlen;
iph = ip_hdr(skb);
tcph = (struct tcphdr *)((void *)iph + iph->ihl * 4);
if (NATCAP_TCPOPT_TYPE(tcpopt->header.type) == NATCAP_TCPOPT_TYPE_NONE) {
goto do_encode;
}
if (tcph->doff * 4 + tcpopt->header.opsize > 60)
return -1;
if (skb_tailroom(skb) < tcpopt->header.opsize && pskb_expand_head(skb, 0, tcpopt->header.opsize, GFP_ATOMIC)) {
return -2;
}
iph = ip_hdr(skb);
tcph = (struct tcphdr *)((void *)iph + iph->ihl * 4);
offlen = skb_tail_pointer(skb) - (unsigned char *)tcph - sizeof(struct tcphdr);
BUG_ON(offlen < 0);
memmove((void *)tcph + sizeof(struct tcphdr) + tcpopt->header.opsize, (void *)tcph + sizeof(struct tcphdr), offlen);
memcpy((void *)tcph + sizeof(struct tcphdr), (void *)tcpopt, tcpopt->header.opsize);
tcph->doff = (tcph->doff * 4 + tcpopt->header.opsize) / 4;
iph->tot_len = htons(ntohs(iph->tot_len) + tcpopt->header.opsize);
skb->len += tcpopt->header.opsize;
skb->tail += tcpopt->header.opsize;
do_encode:
if (tcpopt->header.encryption) {
if (!skb_make_writable(skb, skb->len)) {
return -3;
}
iph = ip_hdr(skb);
tcph = (struct tcphdr *)((void *)iph + iph->ihl * 4);
skb_data_hook(skb, iph->ihl * 4 + tcph->doff * 4, skb->len - (iph->ihl * 4 + tcph->doff * 4), natcap_data_encode);
}
if (tcpopt->header.encryption || NATCAP_TCPOPT_TYPE(tcpopt->header.type) != NATCAP_TCPOPT_TYPE_NONE) {
skb_rcsum_tcpudp(skb);
}
return 0;
}
int natcap_tcp_decode(struct nf_conn *ct, struct sk_buff *skb, struct natcap_TCPOPT *tcpopt, int dir)
{
struct iphdr *iph;
struct tcphdr *tcph;
struct natcap_TCPOPT *opt;
int offlen;
iph = ip_hdr(skb);
tcph = (struct tcphdr *)((void *)iph + iph->ihl * 4);
tcpopt->header.opcode = 0;
tcpopt->header.opsize = 0;
tcpopt->header.type = NATCAP_TCPOPT_TYPE_NONE;
opt = natcap_tcp_decode_header(tcph);
if (opt == NULL) {
goto do_decode;
}
memcpy((void *)tcpopt, (void *)opt, opt->header.opsize);
if (NATCAP_TCPOPT_TYPE(opt->header.type) == NATCAP_TCPOPT_TYPE_CONFUSION) {
goto done;
}
if ((tcpopt->header.type & NATCAP_TCPOPT_SYN)) {
tcph->seq = TCPOPT_NATCAP;
tcph->ack_seq = TCPOPT_NATCAP;
goto do_decode;
}
offlen = skb_tail_pointer(skb) - (unsigned char *)((void *)tcph + sizeof(struct tcphdr) + tcpopt->header.opsize);
BUG_ON(offlen < 0);
memmove((void *)tcph + sizeof(struct tcphdr), (void *)tcph + sizeof(struct tcphdr) + tcpopt->header.opsize, offlen);
tcph->doff = (tcph->doff * 4 - tcpopt->header.opsize) / 4;
iph->tot_len = htons(ntohs(iph->tot_len) - tcpopt->header.opsize);
skb->len -= tcpopt->header.opsize;
skb->tail -= tcpopt->header.opsize;
do_decode:
if (tcpopt->header.encryption) {
if (!skb_make_writable(skb, skb->len)) {
return -3;
}
iph = ip_hdr(skb);
tcph = (struct tcphdr *)((void *)iph + iph->ihl * 4);
skb_data_hook(skb, iph->ihl * 4 + tcph->doff * 4, skb->len - (iph->ihl * 4 + tcph->doff * 4), natcap_data_decode);
}
if (tcpopt->header.encryption || NATCAP_TCPOPT_TYPE(tcpopt->header.type) != NATCAP_TCPOPT_TYPE_NONE) {
skb_rcsum_tcpudp(skb);
}
done:
return 0;
}
int natcap_tcp_encode_fwdupdate(struct sk_buff *skb, struct tcphdr *tcph, const struct tuple *server)
{
struct natcap_TCPOPT *tcpopt;
__be32 target_ip = 0;
u16 oldopt, newopt;
tcpopt = natcap_tcp_decode_header(tcph);
if (tcpopt == NULL) {
return -1;
}
if (NATCAP_TCPOPT_TYPE(tcpopt->header.type) == NATCAP_TCPOPT_TYPE_ALL) {
target_ip = tcpopt->all.data.ip;
} else if (NATCAP_TCPOPT_TYPE(tcpopt->header.type) == NATCAP_TCPOPT_TYPE_DST) {
target_ip = tcpopt->dst.data.ip;
} else {
return -1;
}
oldopt = (tcpopt->header.type << 8) | tcpopt->header.encryption;
if (target_ip == server->ip) {
tcpopt->header.type |= NATCAP_TCPOPT_TARGET;
} else {
tcpopt->header.type &= ~NATCAP_TCPOPT_TARGET;
}
newopt = (tcpopt->header.type << 8) | tcpopt->header.encryption;
if (oldopt != newopt) {
inet_proto_csum_replace2(&tcph->check, skb, htons(oldopt), htons(newopt), false);
return 1;
}
return 0;
}
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
int ip_set_test_src_ipport(const struct nf_hook_state *state, struct sk_buff *skb, const char *ip_set_name)
#else
int ip_set_test_src_ipport(const struct net_device *in, const struct net_device *out, struct sk_buff *skb, const char *ip_set_name)
#endif
{
int ret = 0;
ip_set_id_t id;
struct ip_set *set;
struct ip_set_adt_opt opt;
struct xt_action_param par;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
struct net *net = state->net;
#elif LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
struct net *net = &init_net;
if (in)
net = dev_net(in);
else if (out)
net = dev_net(out);
#endif
memset(&opt, 0, sizeof(opt));
opt.family = NFPROTO_IPV4;
opt.dim = IPSET_DIM_TWO;
opt.flags = IPSET_DIM_ONE_SRC;
opt.cmdflags = 0;
opt.ext.timeout = UINT_MAX;
memset(&par, 0, sizeof(par));
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
par.state = state;
#else
par.in = in;
par.out = out;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 4, 0)
par.net = net;
#endif
#endif
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
id = ip_set_get_byname(net, ip_set_name, &set);
#else
id = ip_set_get_byname(ip_set_name, &set);
#endif
if (id == IPSET_INVALID_ID) {
NATCAP_DEBUG("ip_set '%s' not found\n", ip_set_name);
return 0;
}
ret = ip_set_test(id, skb, &par, &opt);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
ip_set_put_byindex(net, id);
#else
ip_set_put_byindex(id);
#endif
return ret;
}
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
int __ip_set_test_src_ipport(const struct nf_hook_state *state, struct sk_buff *skb, const char *ip_set_name, __be32 *ip_addr, __be32 ip, __be16 *port_addr, __be16 port)
#else
int __ip_set_test_src_ipport(const struct net_device *in, const struct net_device *out, struct sk_buff *skb, const char *ip_set_name, __be32 *ip_addr, __be32 ip, __be16 *port_addr, __be16 port)
#endif
{
int ret = 0;
__be32 old_ip = *ip_addr;
__be16 old_port = *port_addr;
*port_addr = port;
*ip_addr = ip;
ret = IP_SET_test_src_ipport(state, in, out, skb, ip_set_name);
*port_addr = old_port;
*ip_addr = old_ip;
return ret;
}
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
int ip_set_test_src_ip(const struct nf_hook_state *state, struct sk_buff *skb, const char *ip_set_name)
#else
int ip_set_test_src_ip(const struct net_device *in, const struct net_device *out, struct sk_buff *skb, const char *ip_set_name)
#endif
{
int ret = 0;
ip_set_id_t id;
struct ip_set *set;
struct ip_set_adt_opt opt;
struct xt_action_param par;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
struct net *net = state->net;
#elif LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
struct net *net = &init_net;
if (in)
net = dev_net(in);
else if (out)
net = dev_net(out);
#endif
memset(&opt, 0, sizeof(opt));
opt.family = NFPROTO_IPV4;
opt.dim = IPSET_DIM_ONE;
opt.flags = IPSET_DIM_ONE_SRC;
opt.cmdflags = 0;
opt.ext.timeout = UINT_MAX;
memset(&par, 0, sizeof(par));
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
par.state = state;
#else
par.in = in;
par.out = out;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 4, 0)
par.net = net;
#endif
#endif
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
id = ip_set_get_byname(net, ip_set_name, &set);
#else
id = ip_set_get_byname(ip_set_name, &set);
#endif
if (id == IPSET_INVALID_ID) {
NATCAP_DEBUG("ip_set '%s' not found\n", ip_set_name);
return 0;
}
ret = ip_set_test(id, skb, &par, &opt);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
ip_set_put_byindex(net, id);
#else
ip_set_put_byindex(id);
#endif
return ret;
}
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
int ip_set_test_dst_ip(const struct nf_hook_state *state, struct sk_buff *skb, const char *ip_set_name)
#else
int ip_set_test_dst_ip(const struct net_device *in, const struct net_device *out, struct sk_buff *skb, const char *ip_set_name)
#endif
{
int ret = 0;
ip_set_id_t id;
struct ip_set *set;
struct ip_set_adt_opt opt;
struct xt_action_param par;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
struct net *net = state->net;
#elif LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
struct net *net = &init_net;
if (in)
net = dev_net(in);
else if (out)
net = dev_net(out);
#endif
memset(&opt, 0, sizeof(opt));
opt.family = NFPROTO_IPV4;
opt.dim = IPSET_DIM_ONE;
opt.flags = 0;
opt.cmdflags = 0;
opt.ext.timeout = UINT_MAX;
memset(&par, 0, sizeof(par));
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
par.state = state;
#else
par.in = in;
par.out = out;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 4, 0)
par.net = net;
#endif
#endif
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
id = ip_set_get_byname(net, ip_set_name, &set);
#else
id = ip_set_get_byname(ip_set_name, &set);
#endif
if (id == IPSET_INVALID_ID) {
NATCAP_DEBUG("ip_set '%s' not found\n", ip_set_name);
return 0;
}
ret = ip_set_test(id, skb, &par, &opt);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
ip_set_put_byindex(net, id);
#else
ip_set_put_byindex(id);
#endif
return ret;
}
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
int ip_set_test_dst_netport(const struct nf_hook_state *state, struct sk_buff *skb, const char *ip_set_name)
#else
int ip_set_test_dst_netport(const struct net_device *in, const struct net_device *out, struct sk_buff *skb, const char *ip_set_name)
#endif
{
int ret = 0;
ip_set_id_t id;
struct ip_set *set;
struct ip_set_adt_opt opt;
struct xt_action_param par;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
struct net *net = state->net;
#elif LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
struct net *net = &init_net;
if (in)
net = dev_net(in);
else if (out)
net = dev_net(out);
#endif
memset(&opt, 0, sizeof(opt));
opt.family = NFPROTO_IPV4;
opt.dim = IPSET_DIM_TWO;
opt.flags = 0;
opt.cmdflags = 0;
opt.ext.timeout = UINT_MAX;
memset(&par, 0, sizeof(par));
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
par.state = state;
#else
par.in = in;
par.out = out;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 4, 0)
par.net = net;
#endif
#endif
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
id = ip_set_get_byname(net, ip_set_name, &set);
#else
id = ip_set_get_byname(ip_set_name, &set);
#endif
if (id == IPSET_INVALID_ID) {
NATCAP_DEBUG("ip_set '%s' not found\n", ip_set_name);
return 0;
}
ret = ip_set_test(id, skb, &par, &opt);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
ip_set_put_byindex(net, id);
#else
ip_set_put_byindex(id);
#endif
return ret;
}
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
int ip_set_add_src_ip(const struct nf_hook_state *state, struct sk_buff *skb, const char *ip_set_name)
#else
int ip_set_add_src_ip(const struct net_device *in, const struct net_device *out, struct sk_buff *skb, const char *ip_set_name)
#endif
{
int ret = 0;
ip_set_id_t id;
struct ip_set *set;
struct ip_set_adt_opt opt;
struct xt_action_param par;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
struct net *net = state->net;
#elif LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
struct net *net = &init_net;
if (in)
net = dev_net(in);
else if (out)
net = dev_net(out);
#endif
memset(&opt, 0, sizeof(opt));
opt.family = NFPROTO_IPV4;
opt.dim = IPSET_DIM_ONE;
opt.flags = IPSET_DIM_ONE_SRC;
opt.cmdflags = 0;
opt.ext.timeout = UINT_MAX;
memset(&par, 0, sizeof(par));
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
par.state = state;
#else
par.in = in;
par.out = out;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 4, 0)
par.net = net;
#endif
#endif
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
id = ip_set_get_byname(net, ip_set_name, &set);
#else
id = ip_set_get_byname(ip_set_name, &set);
#endif
if (id == IPSET_INVALID_ID) {
NATCAP_DEBUG("ip_set '%s' not found\n", ip_set_name);
return 0;
}
ret = ip_set_add(id, skb, &par, &opt);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
ip_set_put_byindex(net, id);
#else
ip_set_put_byindex(id);
#endif
return ret;
}
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
int ip_set_add_dst_ip(const struct nf_hook_state *state, struct sk_buff *skb, const char *ip_set_name)
#else
int ip_set_add_dst_ip(const struct net_device *in, const struct net_device *out, struct sk_buff *skb, const char *ip_set_name)
#endif
{
int ret = 0;
ip_set_id_t id;
struct ip_set *set;
struct ip_set_adt_opt opt;
struct xt_action_param par;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
struct net *net = state->net;
#elif LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
struct net *net = &init_net;
if (in)
net = dev_net(in);
else if (out)
net = dev_net(out);
#endif
memset(&opt, 0, sizeof(opt));
opt.family = NFPROTO_IPV4;
opt.dim = IPSET_DIM_ONE;
opt.flags = 0;
opt.cmdflags = 0;
opt.ext.timeout = UINT_MAX;
memset(&par, 0, sizeof(par));
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
par.state = state;
#else
par.in = in;
par.out = out;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 4, 0)
par.net = net;
#endif
#endif
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
id = ip_set_get_byname(net, ip_set_name, &set);
#else
id = ip_set_get_byname(ip_set_name, &set);
#endif
if (id == IPSET_INVALID_ID) {
NATCAP_DEBUG("ip_set '%s' not found\n", ip_set_name);
return 0;
}
ret = ip_set_add(id, skb, &par, &opt);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 13, 0)
ip_set_put_byindex(net, id);
#else
ip_set_put_byindex(id);
#endif
return ret;
}
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
int ip_set_del_src_ip(const struct nf_hook_state *state, struct sk_buff *skb, const char *ip_set_name)