youtubeUnblock/youtubeUnblock.c
2024-08-11 21:34:21 +03:00

895 lines
20 KiB
C

#define _GNU_SOURCE
#ifndef __linux__
#error "The package is linux only!"
#endif
#ifdef KERNEL_SPACE
#error "The build aims to the kernel, not userspace"
#endif
#include <libnetfilter_queue/linux_nfnetlink_queue.h>
#include <stdio.h>
#include <stdlib.h>
#include <libmnl/libmnl.h>
#include <libnetfilter_queue/libnetfilter_queue.h>
#include <libnetfilter_queue/libnetfilter_queue_ipv4.h>
#include <libnetfilter_queue/libnetfilter_queue_tcp.h>
#include <libnetfilter_queue/libnetfilter_queue_udp.h>
#include <libnetfilter_queue/pktbuff.h>
#include <netinet/ip.h>
#include <netinet/tcp.h>
#include <netinet/udp.h>
#include <linux/if_ether.h>
#include <linux/netfilter.h>
#include <pthread.h>
#include <sys/socket.h>
#include <unistd.h>
#include <getopt.h>
#include "config.h"
#include "mangle.h"
pthread_mutex_t rawsocket_lock;
struct config_t config = {
.rawsocket = -2,
.threads = THREADS_NUM,
.fragmentation_strategy = FRAGMENTATION_STRATEGY,
.fake_sni_strategy = FAKE_SNI_STRATEGY,
.fake_sni_ttl = FAKE_SNI_TTL,
#ifdef SEG2_DELAY
.seg2_delay = SEG2_DELAY,
#else
.seg2_delay = 0,
#endif
#ifdef USE_GSO
.use_gso = true,
#else
.use_gso = false,
#endif
#ifdef DEBUG
.verbose = true,
#else
.verbose = false,
#endif
.domains_str = defaul_snistr,
.domains_strlen = sizeof(defaul_snistr),
.queue_start_num = DEFAULT_QUEUE_NUM,
};
static long parse_numeric_option(const char* value) {
errno = 0;
if (*value == '\0') {
errno = EINVAL;
return 0;
}
char* end;
long result = strtol(value, &end, 10);
if (*end != '\0') {
errno = EINVAL;
return 0;
}
return result;
}
static void print_version() {
printf("youtubeUnblock\n");
printf("Bypasses youtube detection systems that relies on SNI\n");
}
static void print_usage(const char *argv0) {
print_version();
printf("Usage: %s [ OPTIONS ] \n", argv0);
printf("Options:\n");
printf("\t--queue-num=<number of netfilter queue>\n");
printf("\t--sni-domains=<comma separated domain list>|all\n");
printf("\t--fake-sni={ack,ttl,none}\n");
printf("\t--fake-sni-ttl=<ttl>\n");
printf("\t--frag={tcp,ip,none}\n");
printf("\t--seg2delay=<delay>\n");
printf("\t--threads=<threads number>\n");
printf("\t--silent\n");
printf("\t--no-gso\n");
printf("\n");
}
#define OPT_SNI_DOMAINS 1
#define OPT_FAKE_SNI 2
#define OPT_FAKE_SNI_TTL 3
#define OPT_FRAG 4
#define OPT_SEG2DELAY 5
#define OPT_THREADS 6
#define OPT_SILENT 7
#define OPT_NO_GSO 8
#define OPT_QUEUE_NUM 9
static struct option long_opt[] = {
{"help", 0, 0, 'h'},
{"version", 0, 0, 'v'},
{"sni-domains", 1, 0, OPT_SNI_DOMAINS},
{"fake-sni", 1, 0, OPT_FAKE_SNI},
{"fake-sni-ttl", 1, 0, OPT_FAKE_SNI_TTL},
{"frag", 1, 0, OPT_FRAG},
{"seg2delay", 1, 0, OPT_SEG2DELAY},
{"threads", 1, 0, OPT_THREADS},
{"silent", 0, 0, OPT_SILENT},
{"no-gso", 0, 0, OPT_NO_GSO},
{"queue-num", 1, 0, OPT_QUEUE_NUM},
{0,0,0,0}
};
static int parse_args(int argc, char *argv[]) {
int opt;
int optIdx;
long num;
while ((opt = getopt_long(argc, argv, "hv", long_opt, &optIdx)) != -1) {
switch (opt) {
case 'h':
print_usage(argv[0]);
goto out;
case 'v':
print_version();
goto out;
case OPT_SILENT:
config.verbose = 0;
break;
case OPT_NO_GSO:
config.use_gso = 0;
break;
case OPT_SNI_DOMAINS:
if (!strcmp(optarg, "all")) {
config.all_domains = 1;
}
config.domains_str = optarg;
config.domains_strlen = strlen(config.domains_str);
break;
case OPT_FRAG:
if (strcmp(optarg, "tcp") == 0) {
config.fragmentation_strategy = FRAG_STRAT_TCP;
} else if (strcmp(optarg, "ip") == 0) {
config.fragmentation_strategy = FRAG_STRAT_IP;
} else if (strcmp(optarg, "none") == 0) {
config.fragmentation_strategy = FRAG_STRAT_NONE;
} else {
printf("Invalid option %s\n", long_opt[optIdx].name);
goto error;
}
break;
case OPT_FAKE_SNI:
if (strcmp(optarg, "ack") == 0) {
config.fake_sni_strategy = FKSN_STRAT_ACK_SEQ;
} else if (strcmp(optarg, "ttl") == 0) {
config.fake_sni_strategy = FKSN_STRAT_TTL;
} else if (strcmp(optarg, "none") == 0) {
config.fake_sni_strategy = FKSN_STRAT_NONE;
} else {
errno = EINVAL;
printf("Invalid option %s\n", long_opt[optIdx].name);
goto error;
}
break;
case OPT_SEG2DELAY:
num = parse_numeric_option(optarg);
if (errno != 0 || num < 0) {
printf("Invalid option %s\n", long_opt[optIdx].name);
goto error;
}
config.seg2_delay = num;
break;
case OPT_THREADS:
num = parse_numeric_option(optarg);
if (errno != 0 || num < 0 || num > MAX_THREADS) {
printf("Invalid option %s\n", long_opt[optIdx].name);
goto error;
}
config.threads = num;
break;
case OPT_FAKE_SNI_TTL:
num = parse_numeric_option(optarg);
if (errno != 0 || num < 0 || num > 255) {
printf("Invalid option %s\n", long_opt[optIdx].name);
goto error;
}
config.fake_sni_ttl = num;
break;
case OPT_QUEUE_NUM:
num = parse_numeric_option(optarg);
if (errno != 0 || num < 0) {
printf("Invalid option %s\n", long_opt[optIdx].name);
goto error;
}
config.queue_start_num = num;
break;
default:
goto error;
}
}
errno = 0;
return 0;
out:
errno = 0;
return 1;
error:
print_usage(argv[0]);
errno = EINVAL;
return -1;
}
static int open_socket(struct mnl_socket **_nl) {
struct mnl_socket *nl = NULL;
nl = mnl_socket_open(NETLINK_NETFILTER);
if (nl == NULL) {
perror("mnl_socket_open");
return -1;
}
if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
perror("mnl_socket_bind");
mnl_socket_close(nl);
return -1;
}
*_nl = nl;
return 0;
}
static int close_socket(struct mnl_socket **_nl) {
struct mnl_socket *nl = *_nl;
if (nl == NULL) return 1;
if (mnl_socket_close(nl) < 0) {
perror("mnl_socket_close");
return -1;
}
*_nl = NULL;
return 0;
}
static int open_raw_socket(void) {
if (config.rawsocket != -2) {
errno = EALREADY;
perror("Raw socket is already opened");
return -1;
}
config.rawsocket = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
if (config.rawsocket == -1) {
perror("Unable to create raw socket");
return -1;
}
int mark = RAWSOCKET_MARK;
if (setsockopt(config.rawsocket, SOL_SOCKET, SO_MARK, &mark, sizeof(mark)) < 0)
{
fprintf(stderr, "setsockopt(SO_MARK, %d) failed\n", mark);
return -1;
}
int mst = pthread_mutex_init(&rawsocket_lock, NULL);
if (mst) {
fprintf(stderr, "Mutex err: %d\n", mst);
close(config.rawsocket);
errno = mst;
return -1;
}
return config.rawsocket;
}
static int close_raw_socket(void) {
if (config.rawsocket < 0) {
errno = EALREADY;
perror("Raw socket is not set");
return -1;
}
if (close(config.rawsocket)) {
perror("Unable to close raw socket");
pthread_mutex_destroy(&rawsocket_lock);
return -1;
}
pthread_mutex_destroy(&rawsocket_lock);
config.rawsocket = -2;
return 0;
}
static int send_raw_socket(const uint8_t *pkt, uint32_t pktlen) {
int ret;
if (pktlen > AVAILABLE_MTU) {
if (config.verbose)
printf("Split packet!\n");
uint8_t buff1[MNL_SOCKET_BUFFER_SIZE];
uint32_t buff1_size = MNL_SOCKET_BUFFER_SIZE;
uint8_t buff2[MNL_SOCKET_BUFFER_SIZE];
uint32_t buff2_size = MNL_SOCKET_BUFFER_SIZE;
switch (config.fragmentation_strategy) {
case FRAG_STRAT_TCP:
if ((ret = tcp4_frag(pkt, pktlen, AVAILABLE_MTU-128,
buff1, &buff1_size, buff2, &buff2_size)) < 0) {
errno = -ret;
return ret;
}
break;
case FRAG_STRAT_IP:
if ((ret = ip4_frag(pkt, pktlen, AVAILABLE_MTU-128,
buff1, &buff1_size, buff2, &buff2_size)) < 0) {
errno = -ret;
return ret;
}
break;
default:
errno = EINVAL;
printf("send_raw_socket: Packet is too big but fragmentation is disabled!\n");
return -EINVAL;
}
int sent = 0;
int status = send_raw_socket(buff1, buff1_size);
if (status >= 0) sent += status;
else {
return status;
}
status = send_raw_socket(buff2, buff2_size);
if (status >= 0) sent += status;
else {
return status;
}
return sent;
}
struct iphdr *iph;
if ((ret = ip4_payload_split(
(uint8_t *)pkt, pktlen, &iph, NULL, NULL, NULL)) < 0) {
errno = -ret;
return ret;
}
struct sockaddr_in daddr = {
.sin_family = AF_INET,
/* Always 0 for raw socket */
.sin_port = 0,
.sin_addr = {
.s_addr = iph->daddr
}
};
pthread_mutex_lock(&rawsocket_lock);
int sent = sendto(config.rawsocket,
pkt, pktlen, 0,
(struct sockaddr *)&daddr, sizeof(daddr));
pthread_mutex_unlock(&rawsocket_lock);
/* The function will return -errno on error as well as errno value set itself */
if (sent < 0) sent = -errno;
return sent;
}
struct packet_data {
uint32_t id;
uint16_t hw_proto;
uint8_t hook;
void *payload;
uint16_t payload_len;
};
// Per-queue data. Passed to queue_cb.
struct queue_data {
struct mnl_socket **_nl;
int queue_num;
};
/**
* Used to accept unsupported packets (GSOs)
*/
static int fallback_accept_packet(uint32_t id, struct queue_data qdata) {
char buf[MNL_SOCKET_BUFFER_SIZE];
struct nlmsghdr *verdnlh;
verdnlh = nfq_nlmsg_put(buf, NFQNL_MSG_VERDICT, qdata.queue_num);
nfq_nlmsg_verdict_put(verdnlh, id, NF_ACCEPT);
if (mnl_socket_sendto(*qdata._nl, verdnlh, verdnlh->nlmsg_len) < 0) {
perror("mnl_socket_send");
return MNL_CB_ERROR;
}
return MNL_CB_OK;
}
struct dps_t {
uint8_t *pkt;
uint32_t pktlen;
// Time for the packet in milliseconds
uint32_t timer;
};
// Note that the thread will automatically release dps_t and pkt_buff
void *delay_packet_send(void *data) {
struct dps_t *dpdt = data;
uint8_t *pkt = dpdt->pkt;
uint32_t pktlen = dpdt->pktlen;
usleep(dpdt->timer * 1000);
int ret = send_raw_socket(pkt, pktlen);
if (ret < 0) {
errno = -ret;
perror("send delayed raw packet");
}
free(pkt);
free(dpdt);
return NULL;
}
static int process_packet(const struct packet_data packet, struct queue_data qdata) {
char buf[MNL_SOCKET_BUFFER_SIZE];
struct nlmsghdr *verdnlh;
#ifdef DEBUG_LOGGING
printf("packet received (id=%u hw=0x%04x hook=%u, payload len %u)\n",
packet.id, packet.hw_proto, packet.hook, packet.payload_len);
#endif
if (packet.hw_proto != ETH_P_IP) {
return fallback_accept_packet(packet.id, qdata);
}
const int family = AF_INET;
const uint8_t *raw_payload = packet.payload;
size_t raw_payload_len = packet.payload_len;
const struct iphdr *iph;
uint32_t iph_len;
const struct tcphdr *tcph;
uint32_t tcph_len;
const uint8_t *data;
uint32_t dlen;
int ret = tcp4_payload_split((uint8_t *)raw_payload, raw_payload_len,
(struct iphdr **)&iph, &iph_len, (struct tcphdr **)&tcph, &tcph_len,
(uint8_t **)&data, &dlen);
if (ret < 0) {
goto fallback;
}
struct verdict vrd = analyze_tls_data(data, dlen);
verdnlh = nfq_nlmsg_put(buf, NFQNL_MSG_VERDICT, qdata.queue_num);
nfq_nlmsg_verdict_put(verdnlh, packet.id, NF_ACCEPT);
if (vrd.target_sni) {
if (config.verbose)
printf("SNI target detected\n");
if (dlen > 1480) {
if (config.verbose)
fprintf(stderr, "WARNING! Client Hello packet is too big and may cause issues!\n");
}
uint8_t frag1[MNL_SOCKET_BUFFER_SIZE];
uint8_t frag2[MNL_SOCKET_BUFFER_SIZE];
uint32_t f1len = MNL_SOCKET_BUFFER_SIZE;
uint32_t f2len = MNL_SOCKET_BUFFER_SIZE;
nfq_nlmsg_verdict_put(verdnlh, packet.id, NF_DROP);
int ret = 0;
nfq_ip_set_checksum((struct iphdr *)iph);
nfq_tcp_compute_checksum_ipv4(
(struct tcphdr *)tcph, (struct iphdr *)iph);
if (config.fake_sni_strategy != FKSN_STRAT_NONE) {
uint8_t rfsiph[60];
uint8_t rfstcph[60];
memcpy(rfsiph, iph, iph_len);
memcpy(rfstcph, tcph, tcph_len);
struct iphdr *fsiph = (void *)rfsiph;
struct tcphdr *fstcph = (void *)rfstcph;
for (int i = 0; i < 10; i++) {
uint8_t fake_sni[MNL_SOCKET_BUFFER_SIZE];
uint32_t fsn_len = MNL_SOCKET_BUFFER_SIZE;
ret = gen_fake_sni(fsiph, fstcph, fake_sni, &fsn_len);
if (ret < 0) {
errno = -ret;
perror("gen_fake_sni");
goto fallback;
}
printf("%d\n", i);
ret = send_raw_socket(fake_sni, fsn_len);
if (ret < 0) {
errno = -ret;
perror("send fake sni");
goto fallback;
}
uint32_t iph_len;
uint32_t tcph_len;
uint32_t plen;
tcp4_payload_split(fake_sni, fsn_len, &fsiph, &iph_len, &fstcph, &tcph_len, NULL, &plen);
fstcph->seq = htonl(ntohl(tcph->seq) + plen * (i + 1));
memcpy(rfsiph, fsiph, iph_len);
memcpy(rfstcph, fstcph, tcph_len);
fsiph = (void *)rfsiph;
fstcph = (void *)rfstcph;
}
}
size_t ipd_offset;
size_t mid_offset;
switch (config.fragmentation_strategy) {
case FRAG_STRAT_TCP:
ipd_offset = vrd.sni_offset;
mid_offset = ipd_offset + vrd.sni_len / 2;
if ((ret = tcp4_frag(raw_payload, raw_payload_len,
mid_offset, frag1, &f1len, frag2, &f2len)) < 0) {
errno = -ret;
perror("tcp4_frag");
goto fallback;
}
break;
case FRAG_STRAT_IP:
ipd_offset = ((char *)data - (char *)tcph) + vrd.sni_offset;
mid_offset = ipd_offset + vrd.sni_len / 2;
mid_offset += 8 - mid_offset % 8;
if ((ret = ip4_frag(raw_payload, raw_payload_len,
mid_offset, frag1, &f1len, frag2, &f2len)) < 0) {
errno = -ret;
perror("ip4_frag");
goto fallback;
}
break;
default:
ret = send_raw_socket(raw_payload, raw_payload_len);
if (ret < 0) {
errno = -ret;
perror("raw pack send");
goto fallback;
}
goto send_verd;
}
ret = send_raw_socket(frag2, f2len);
if (ret < 0) {
errno = -ret;
perror("raw frags send: frag2");
goto fallback;
}
if (config.seg2_delay) {
struct dps_t *dpdt = malloc(sizeof(struct dps_t));
dpdt->pkt = malloc(f1len);
memcpy(dpdt->pkt, frag1, f1len);
dpdt->pktlen = f1len;
dpdt->timer = config.seg2_delay;
pthread_t thr;
pthread_create(&thr, NULL, delay_packet_send, dpdt);
pthread_detach(thr);
} else {
ret = send_raw_socket(frag1, f1len);
if (ret < 0) {
errno = -ret;
perror("raw frags send: frag1");
goto fallback;
}
}
}
/*
if (pktb_mangled(pktb)) {
if (config.versose)
printf("Mangled!\n");
nfq_nlmsg_verdict_put_pkt(
verdnlh, pktb_data(pktb), pktb_len(pktb));
}
*/
send_verd:
if (mnl_socket_sendto(*qdata._nl, verdnlh, verdnlh->nlmsg_len) < 0) {
perror("mnl_socket_send");
goto error;
}
return MNL_CB_OK;
fallback:
return fallback_accept_packet(packet.id, qdata);
error:
return MNL_CB_ERROR;
}
static int queue_cb(const struct nlmsghdr *nlh, void *data) {
struct queue_data *qdata = data;
struct nfqnl_msg_packet_hdr *ph = NULL;
struct nlattr *attr[NFQA_MAX+1] = {0};
struct packet_data packet = {0};
if (nfq_nlmsg_parse(nlh, attr) < 0) {
perror("Attr parse");
return MNL_CB_ERROR;
}
if (attr[NFQA_PACKET_HDR] == NULL) {
errno = ENODATA;
perror("Metaheader not set");
return MNL_CB_ERROR;
}
ph = mnl_attr_get_payload(attr[NFQA_PACKET_HDR]);
packet.id = ntohl(ph->packet_id);
packet.hw_proto = ntohs(ph->hw_protocol);
packet.hook = ph->hook;
packet.payload_len = mnl_attr_get_payload_len(attr[NFQA_PAYLOAD]);
packet.payload = mnl_attr_get_payload(attr[NFQA_PAYLOAD]);
if (attr[NFQA_CAP_LEN] != NULL && ntohl(mnl_attr_get_u32(attr[NFQA_CAP_LEN])) != packet.payload_len) {
fprintf(stderr, "The packet was truncated! Skip!\n");
return fallback_accept_packet(packet.id, *qdata);
}
if (attr[NFQA_MARK] != NULL) {
// Skip packets sent by rawsocket to escape infinity loop.
if ((ntohl(mnl_attr_get_u32(attr[NFQA_MARK])) & RAWSOCKET_MARK) ==
RAWSOCKET_MARK) {
return fallback_accept_packet(packet.id, *qdata);
}
}
return process_packet(packet, *qdata);
}
#define BUF_SIZE (0xffff + (MNL_SOCKET_BUFFER_SIZE / 2))
int init_queue(int queue_num) {
struct mnl_socket *nl;
if (open_socket(&nl)) {
perror("Unable to open socket");
return -1;
}
uint32_t portid = mnl_socket_get_portid(nl);
struct nlmsghdr *nlh;
char buf[BUF_SIZE];
nlh = nfq_nlmsg_put(buf, NFQNL_MSG_CONFIG, queue_num);
nfq_nlmsg_cfg_put_cmd(nlh, AF_INET, NFQNL_CFG_CMD_BIND);
if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) {
perror("mnl_socket_send");
goto die;
}
nlh = nfq_nlmsg_put(buf, NFQNL_MSG_CONFIG, queue_num);
nfq_nlmsg_cfg_put_params(nlh, NFQNL_COPY_PACKET, 0xffff);
if (config.use_gso) {
mnl_attr_put_u32(nlh, NFQA_CFG_FLAGS, htonl(NFQA_CFG_F_GSO));
mnl_attr_put_u32(nlh, NFQA_CFG_MASK, htonl(NFQA_CFG_F_GSO));
}
if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) {
perror("mnl_socket_send");
goto die;
}
/* ENOBUFS is signalled to userspace when packets were lost
* on kernel side. In most cases, userspace isn't interested
* in this information, so turn it off.
*/
int ret = 1;
mnl_socket_setsockopt(nl, NETLINK_NO_ENOBUFS, &ret, sizeof(int));
struct queue_data qdata = {
._nl = &nl,
.queue_num = queue_num
};
printf("Queue %d started\n", qdata.queue_num);
while (1) {
ret = mnl_socket_recvfrom(nl, buf, BUF_SIZE);
if (ret == -1) {
perror("mnl_socket_recvfrom");
continue;
}
ret = mnl_cb_run(buf, ret, 0, portid, queue_cb, &qdata);
if (ret < 0) {
perror("mnl_cb_run");
}
}
close_socket(&nl);
return 0;
die:
close_socket(&nl);
return -1;
}
// Per-queue config. Used to initialize a queue. Passed to wrapper
struct queue_conf {
uint16_t i;
int queue_num;
};
struct queue_res {
int status;
};
static struct queue_res defqres = {0};
static struct queue_res threads_reses[MAX_THREADS];
void *init_queue_wrapper(void *qdconf) {
struct queue_conf *qconf = qdconf;
struct queue_res *thres = threads_reses + qconf->i;
thres->status = init_queue(qconf->queue_num);
fprintf(stderr, "Thread %d exited with status %d\n", qconf->i, thres->status);
return thres;
}
int main(int argc, char *argv[]) {
int ret;
if ((ret = parse_args(argc, argv)) != 0) {
if (ret < 0) {
perror("Unable to parse args");
exit(EXIT_FAILURE);
}
exit(EXIT_SUCCESS);
}
switch (config.fragmentation_strategy) {
case FRAG_STRAT_TCP:
printf("Using TCP segmentation\n");
break;
case FRAG_STRAT_IP:
printf("Using IP fragmentation\n");
break;
default:
printf("SNI fragmentation is disabled\n");
break;
}
if (config.seg2_delay) {
printf("Some outgoing googlevideo request segments will be delayed for %d ms as of seg2_delay define\n", config.seg2_delay);
}
switch (config.fake_sni_strategy) {
case FKSN_STRAT_TTL:
printf("Fake SNI will be sent before each request, TTL strategy will be used with TTL %d\n", config.fake_sni_ttl);
break;
case FRAG_STRAT_IP:
printf("Fake SNI will be sent before each request, Ack-Seq strategy will be used\n");
break;
default:
printf("SNI fragmentation is disabled\n");
break;
}
if (config.use_gso) {
printf("GSO is enabled\n");
}
if (open_raw_socket() < 0) {
perror("Unable to open raw socket");
exit(EXIT_FAILURE);
}
struct queue_res *qres = &defqres;
if (config.threads == 1) {
struct queue_conf tconf = {
.i = 0,
.queue_num = config.queue_start_num
};
qres = init_queue_wrapper(&tconf);
} else {
printf("%d threads wil be used\n", config.threads);
struct queue_conf thread_confs[MAX_THREADS];
pthread_t threads[MAX_THREADS];
for (int i = 0; i < config.threads; i++) {
struct queue_conf *tconf = thread_confs + i;
pthread_t *thr = threads + i;
tconf->queue_num = config.queue_start_num + i;
tconf->i = i;
pthread_create(thr, NULL, init_queue_wrapper, tconf);
}
void *res;
for (int i = 0; i < config.threads; i++) {
pthread_join(threads[i], &res);
qres = res;
}
}
if (close_raw_socket() < 0) {
perror("Unable to close raw socket");
exit(EXIT_FAILURE);
}
return qres->status;
}