youtubeUnblock/iptk_YTUNBLOCK.c
2024-09-01 16:52:41 +03:00

416 lines
8.7 KiB
C

#define _GNU_SOURCE
// Kernel module for youtubeUnblock.
// Make with make kmake && sudo iptables -t mangle -D OUTPUT 1 && sudo make kreload && sudo iptables -t mangle -I OUTPUT -p tcp -j YTUNBLOCK
#include <linux/module.h>
#include <linux/init.h>
#include <linux/printk.h>
#include <linux/mutex.h>
#include <linux/socket.h>
#include <linux/net.h>
#include <linux/netfilter/x_tables.h>
#include "ipt_YTUNBLOCK.h"
#include "mangle.h"
#include "config.h"
#include "raw_replacements.h"
#include "utils.h"
#include "logging.h"
struct config_t config = {
.threads = THREADS_NUM,
.frag_sni_reverse = 1,
.frag_sni_faked = 0,
.fragmentation_strategy = FRAGMENTATION_STRATEGY,
.faking_strategy = FAKING_STRATEGY,
.faking_ttl = FAKE_TTL,
.fake_sni = 1,
.fake_sni_seq_len = 1,
.frag_middle_sni = 1,
.frag_sni_pos = 1,
.use_ipv6 = 1,
.fakeseq_offset = 10000,
.mark = DEFAULT_RAWSOCKET_MARK,
.synfake = 0,
.synfake_len = 0,
.sni_detection = SNI_DETECTION_PARSE,
#ifdef SEG2_DELAY
.seg2_delay = SEG2_DELAY,
#else
.seg2_delay = 0,
#endif
#ifdef USE_GSO
.use_gso = 1,
#else
.use_gso = false,
#endif
#ifdef DEBUG
.verbose = 2,
#else
.verbose = 0,
#endif
.domains_str = defaul_snistr,
.domains_strlen = sizeof(defaul_snistr),
.queue_start_num = DEFAULT_QUEUE_NUM,
.fake_sni_pkt = fake_sni_old,
.fake_sni_pkt_sz = sizeof(fake_sni_old) - 1, // - 1 for null-terminator
};
MODULE_LICENSE("GPL");
MODULE_VERSION("0.3.2");
MODULE_AUTHOR("Vadim Vetrov <vetrovvd@gmail.com>");
MODULE_DESCRIPTION("Linux kernel module for youtube unblock");
static struct socket *rawsocket;
DEFINE_MUTEX(rslock);
static struct socket *raw6socket;
DEFINE_MUTEX(rs6lock);
static int open_raw_socket(void) {
int ret = 0;
ret = sock_create(AF_INET, SOCK_RAW, IPPROTO_RAW, &rawsocket);
if (ret < 0) {
pr_alert("Unable to create raw socket\n");
goto err;
}
sockptr_t optval = {
.kernel = NULL,
.is_kernel = 1
};
int mark = config.mark;
optval.kernel = &mark;
ret = sock_setsockopt(rawsocket, SOL_SOCKET, SO_MARK, optval, sizeof(mark));
if (ret < 0)
{
pr_alert("setsockopt(SO_MARK, %d) failed\n", mark);
goto sr_err;
}
int one = 1;
optval.kernel = &one;
return 0;
sr_err:
sock_release(rawsocket);
err:
return ret;
}
static void close_raw_socket(void) {
sock_release(rawsocket);
}
static int send_raw_ipv4(const uint8_t *pkt, uint32_t pktlen) {
int ret = 0;
if (pktlen > AVAILABLE_MTU) return -ENOMEM;
struct iphdr *iph;
if ((ret = ip4_payload_split(
(uint8_t *)pkt, pktlen, &iph, NULL, NULL, NULL)) < 0) {
return ret;
}
struct sockaddr_in daddr = {
.sin_family = AF_INET,
.sin_port = 0,
.sin_addr = {
.s_addr = iph->daddr
}
};
struct msghdr msg;
struct kvec iov;
iov.iov_base = (__u8 *)pkt;
iov.iov_len = pktlen;
iov_iter_kvec(&msg.msg_iter, READ, &iov, 1, 1);
msg.msg_flags = 0;
msg.msg_name = &daddr;
msg.msg_namelen = sizeof(struct sockaddr_in);
msg.msg_control = NULL;
msg.msg_controllen = 0;
mutex_lock(&rslock);
ret = kernel_sendmsg(rawsocket, &msg, &iov, 1, pktlen);
mutex_unlock(&rslock);
return ret;
}
static int open_raw6_socket(void) {
int ret = 0;
ret = sock_create(AF_INET6, SOCK_RAW, IPPROTO_RAW, &raw6socket);
if (ret < 0) {
pr_alert("Unable to create raw socket\n");
goto err;
}
sockptr_t optval = {
.kernel = NULL,
.is_kernel = 1
};
int mark = config.mark;
optval.kernel = &mark;
ret = sock_setsockopt(raw6socket, SOL_SOCKET, SO_MARK, optval, sizeof(mark));
if (ret < 0)
{
pr_alert("setsockopt(SO_MARK, %d) failed\n", mark);
goto sr_err;
}
int one = 1;
optval.kernel = &one;
return 0;
sr_err:
sock_release(raw6socket);
err:
return ret;
}
static void close_raw6_socket(void) {
sock_release(raw6socket);
}
static int send_raw_ipv6(const uint8_t *pkt, uint32_t pktlen) {
int ret = 0;
if (pktlen > AVAILABLE_MTU) return -ENOMEM;
struct ip6_hdr *iph;
if ((ret = ip6_payload_split(
(uint8_t *)pkt, pktlen, &iph, NULL, NULL, NULL)) < 0) {
return ret;
}
struct sockaddr_in6 daddr = {
.sin6_family = AF_INET6,
/* Always 0 for raw socket */
.sin6_port = 0,
.sin6_addr = iph->ip6_dst
};
struct msghdr msg;
struct kvec iov;
iov.iov_base = (__u8 *)pkt;
iov.iov_len = pktlen;
iov_iter_kvec(&msg.msg_iter, READ, &iov, 1, 1);
msg.msg_flags = 0;
msg.msg_name = &daddr;
msg.msg_namelen = sizeof(struct sockaddr_in6);
msg.msg_control = NULL;
msg.msg_controllen = 0;
mutex_lock(&rs6lock);
ret = kernel_sendmsg(raw6socket, &msg, &iov, 1, pktlen);
mutex_unlock(&rs6lock);
return ret;
}
static int send_raw_socket(const uint8_t *pkt, uint32_t pktlen) {
int ret;
if (pktlen > AVAILABLE_MTU) {
pr_warn("The packet is too big and may cause issues!");
NETBUF_ALLOC(buff1, MAX_PACKET_SIZE);
if (!NETBUF_CHECK(buff1)) {
lgerror("Allocation error", -ENOMEM);
return -ENOMEM;
}
NETBUF_ALLOC(buff2, MAX_PACKET_SIZE);
if (!NETBUF_CHECK(buff2)) {
lgerror("Allocation error", -ENOMEM);
NETBUF_FREE(buff2);
return -ENOMEM;
}
uint32_t buff1_size = MAX_PACKET_SIZE;
uint32_t buff2_size = MAX_PACKET_SIZE;
switch (config.fragmentation_strategy) {
case FRAG_STRAT_TCP:
if ((ret = tcp_frag(pkt, pktlen, AVAILABLE_MTU-128,
buff1, &buff1_size, buff2, &buff2_size)) < 0) {
goto erret_lc;
}
break;
case FRAG_STRAT_IP:
if ((ret = ip4_frag(pkt, pktlen, AVAILABLE_MTU-128,
buff1, &buff1_size, buff2, &buff2_size)) < 0) {
goto erret_lc;
}
break;
default:
pr_warn("send_raw_socket: Packet is too big but fragmentation is disabled!");
ret = -EINVAL;
goto erret_lc;
}
int sent = 0;
ret = send_raw_socket(buff1, buff1_size);
if (ret >= 0) sent += ret;
else {
goto erret_lc;
}
ret = send_raw_socket(buff2, buff2_size);
if (ret >= 0) sent += ret;
else {
goto erret_lc;
}
NETBUF_FREE(buff1);
NETBUF_FREE(buff2);
return sent;
erret_lc:
NETBUF_FREE(buff1);
NETBUF_FREE(buff2);
return ret;
}
int ipvx = netproto_version(pkt, pktlen);
if (ipvx == IP4VERSION)
return send_raw_ipv4(pkt, pktlen);
else if (ipvx == IP6VERSION)
return send_raw_ipv6(pkt, pktlen);
printf("proto version %d is unsupported\n", ipvx);
return -EINVAL;
}
static void delay_packet_send(const unsigned char *data, unsigned int data_len, unsigned int delay_ms) {
pr_warn("delay_packet_send won't work on current youtubeUnblock version");
send_raw_socket(data, data_len);
}
struct instance_config_t instance_config = {
.send_raw_packet = send_raw_socket,
.send_delayed_packet = delay_packet_send,
};
static unsigned int ykb_tg(struct sk_buff *skb, const struct xt_action_param *par)
{
if ((skb->mark & config.mark) == config.mark)
return XT_CONTINUE;
if (skb->head == NULL) return XT_CONTINUE;
uint32_t buflen = skb->len;
if (buflen > MAX_PACKET_SIZE)
goto accept;
NETBUF_ALLOC(buf, buflen);
if (!NETBUF_CHECK(buf))
goto no_free;
if (skb_copy_bits(skb, 0, buf, buflen) < 0) {
pr_err("Unable copy bits\n");
goto accept;
}
int vrd = process_packet(buf, buflen);
switch(vrd) {
case PKT_ACCEPT:
goto accept;
case PKT_DROP:
goto drop;
}
accept:
NETBUF_FREE(buf);
no_free:
return XT_CONTINUE;
drop:
NETBUF_FREE(buf);
kfree_skb(skb);
return NF_STOLEN;
}
static int ykb_chk(const struct xt_tgchk_param *par) {
return 0;
}
static struct xt_target ykb_tg_reg __read_mostly = {
.name = "YTUNBLOCK",
.target = ykb_tg,
.table = "mangle",
.hooks = (1 << NF_INET_LOCAL_OUT) | (1 << NF_INET_FORWARD),
.targetsize = sizeof(struct xt_ytunblock_tginfo),
.proto = IPPROTO_TCP,
.family = NFPROTO_IPV4,
.checkentry = ykb_chk,
.me = THIS_MODULE,
};
static struct xt_target ykb6_tg_reg __read_mostly = {
.name = "YTUNBLOCK",
.target = ykb_tg,
.table = "mangle",
.hooks = (1 << NF_INET_LOCAL_OUT) | (1 << NF_INET_FORWARD),
.targetsize = sizeof(struct xt_ytunblock_tginfo),
.proto = IPPROTO_TCP,
.family = NFPROTO_IPV6,
.checkentry = ykb_chk,
.me = THIS_MODULE,
};
static int __init ykb_init(void) {
int ret = 0;
ret = open_raw_socket();
if (ret < 0) goto err;
if (config.use_ipv6) {
ret = open_raw6_socket();
if (ret < 0) goto close_rawsocket;
ret = xt_register_target(&ykb6_tg_reg);
if (ret < 0) goto close_raw6socket;
}
ret = xt_register_target(&ykb_tg_reg);
if (ret < 0) goto close_xt6_target;
pr_info("youtubeUnblock kernel module started.\n");
return 0;
close_xt6_target:
if (config.use_ipv6) xt_unregister_target(&ykb6_tg_reg);
close_raw6socket:
if (config.use_ipv6) close_raw6_socket();
close_rawsocket:
close_raw_socket();
err:
return ret;
}
static void __exit ykb_destroy(void) {
xt_unregister_target(&ykb_tg_reg);
if (config.use_ipv6) xt_unregister_target(&ykb6_tg_reg);
if (config.use_ipv6) close_raw6_socket();
close_raw_socket();
pr_info("youtubeUnblock kernel module destroyed.\n");
}
module_init(ykb_init);
module_exit(ykb_destroy);