Merge branch 'main' into kern_mod

2024-12-22 06:15:31 +00:00 · 2024-08-04 02:20:09 +03:00 · 2024-08-04 02:20:09 +03:00 · 97ee3f1e72
commit 97ee3f1e72
parent 66191b10f7 be40bc91e7
10 changed files with 266 additions and 78 deletions
--- a/README.md
+++ b/README.md
@ -1,7 +1,7 @@
 # youtubeUnblock
 Bypasses Googlevideo detection systems that relies on SNI. The package is for Linux only. 

-For Windows use [GoodbyeDPI from VladikSS](https://github.com/ValdikSS/GoodbyeDPI) (Users points out that working options for it are `goodbyedpi.exe -6 --frag-by-sni`.) The same behavior is also implemented in [zapret package for linux](https://github.com/bol-van/zapret).
+For Windows use [GoodbyeDPI from ValdikSS](https://github.com/ValdikSS/GoodbyeDPI) (you can find how to use it for YouTube [here](https://github.com/ValdikSS/GoodbyeDPI/issues/378)) The same behavior is also implemented in [zapret package for linux](https://github.com/bol-van/zapret).

 ## How it works:
 Lets look from the DPIses side of view: All they have is ip and tcp information, higher-level data is encrypted. So from the IP header only IP address might be helpful for them. In tcp here is basically nothing. So they may handle IP addresses and process it. What's wrong? Google servers are on the way: It is very hard to handle all that infrastracture. One server may host multiple websites and it is very bad if them block, say Google Search trying to block googlevideo. But even if googlevideo servers have their own ip for only googlevideo purposes, here is a problem about how large is Google infrastracture and how much servers are here. The DPIs can't even parse normally all the servers, because each video may live on it's cache server. So what's else? Let's take a look at a TLS level. All information here is encrypted. All... Except hello messages! They are used to initialize handshake connections and hold tons of helpful information. If we talk about TLS v1.3, it is optimized to transfer as less information as possible unencrypted. But here is only one thing that may point us which domain the user wants to connect, the SNI extension. It transfers all domain names unencrypted. Exactly what we need! And DPIs may use this thing to detect google video connections and slow down them (In fact they are corrupting a tcp connection with bad packets).
@ -17,27 +17,54 @@ You may read further in an [yt-dlp issue page](https://github.com/yt-dlp/yt-dlp/
 When the packet is joining the queue, the application checks sni payload to be googlevideo (right how the DPIs do), segmentates/fragmentates (both TCP and IP fragmentation techniques are supported) and posts the packet. Note that it is impossible to post two fragmented packets from one netfilter queue verdict. Instead, the application drops an original packet and makes another linux raw socket to post the packets in the network. To escape infinity loops the socket marks outgoing packets and the application automatically accepts it.

 ## Usage:
+Before compilation make sure `gcc`, `make`, `autoconf`, `automake`, `pkg-config` and `libtool` is installed. For Fedora `glibc-static` should be installed as well.
 Compile with `make`. Install with `make install`. The package include libnetfilter_queue, libnfnetlink and libmnl as static dependencies. The package requires linux-headers and kernel built with netfilter nfqueue support.

 You should also configure iptables for this to start working:
-```iptables -A OUTPUT -p tcp --dport 443 -j NFQUEUE --queue-num 537 --queue-bypass```
+```iptables -A OUTPUT -p tcp --dport 443 -j NFQUEUE --queue-num 537 --queue-bypass``` (or do ```nft add rule ip mangle OUTPUT tcp dport 443 counter queue num 537 bypass``` for nftables.)
 Here iptables serves every tcp packet, destinating port 443 for this userspace packet analyzer (via netfilter kernel module) queue-num may be any number from 0 to 65565. --queue-bypass allows traffic to pass if the application is down.

+Also tips to explicitly accept all important outgoing raw packets from youtubeUnblock from [Troubleshooting EPERMS](https://github.com/Waujito/youtubeUnblock?tab=readme-ov-file#troubleshooting-eperms-operation-not-permitted) may be useful to avoid issues.
+
 Run an application with `youtubeUnblock 537` where `537` stands for the queue-num (must be the same as in the iptables rule).

-Systemd daemon is also available. Do `systemctl enable --now youtubeUnblock.service` after installation (uses queue-num `537`).
+Systemd daemon is also available. Do `systemctl enable --now youtubeUnblock.service` after installation (uses queue-num `537`). Please, note that systemd will configure iptables automatically. If you have troubles with it, delete ExecStartPre and ExecStop from youtubeUnblock.service and configure iptables manually (may be a useful case for nftables).
+
+If you don't want youtubeUnblock to log on each googlevideo request pass -DSILENT as CFLAGS.

 Also DNS over HTTPS (DOH) is preferred for additional anonimity. 

+## Troubleshooting
+If you have any troubles with youtubeUnblock, here are some options to tune. If them don't work in your case, please, open an issue. You can pass these options in make CFLAGS (`make CFLAGS=...`) or edit CFLAGS variable in Makefile.
+Available flags:
+- -DUSE_SEG2_DELAY This flag forces youtubeUnblock to wait little bit before send the 2nd part of the split packet. You can tune the amount of time in `#define SEG2_DELAY 100` where 100 stands for milliseconds.
+- -DNO_FAKE_SNI This flag disables -DFAKE_SNI which forces youtubeUnblock to send at least three packets instead of one with TLS ClientHello: Fake ClientHello, 1st part of original ClientHello, 2nd part of original ClientHello. This flag may be related to some Operation not permitted error messages, so befor open an issue refer to FAQ for EPERMS.
+- -DNOUSE_GSO This flag disables fix for Google Chrome fat ClientHello. The GSO is well tested now, so this flag probably won't fix anything.
+
+If you are on Chromium you may have to disable kyber (the feature that makes the TLS ClientHello very fat). I've got the problem with it on router, so to escape possibly errors it is better to just disable it: in chrome://flags search for kyber and switch it to disabled state. 
+
+### Troubleshooting EPERMS (Operation not permitted)
+EPERM may occur in a lot of places but generally here are two: mnl_cb_run and when sending the packet via rawsocket (raw_frags_send and send fake sni).
+- mnl_cb_run Operation not permitted indicates that another instance of youtubeUnblock is running on the specified queue-num.
+- rawsocket Operation not permitted indicates that the packet is being dropped by nefilter rules. In fact this is a hint from the kernel that something wrong is going on and we should check the firewall rules. Before dive into the problem let's make it clean how the mangled packets are being sent. Nefilter queue provides us with the ability to mangle the packet on fly but that is not suitable for this program because we need to split the packet to at least two independent packets. So we are using [linux raw sockets](https://man7.org/linux/man-pages/man7/raw.7.html) which allows us to send any ipv4 packet. **The packet goes from the OUTPUT chain even when NFQUEUE is set up on FORWARD (suitable for OpenWRT).** So we need to escape packet rejects here.
+    * raw_frags_send EPERM: just make sure outgoing traffic is allowed (RELATED,ESTABLISHED should work, if not, go to step 3)
+    * send fake sni EPERM: Fake SNI is out-of-state thing and will likely corrupt the connection (the behavior is expected). conntrack considers it as an invalid packet. By default OpenWRT set up to drop outgoing packets like this one. You may delete nftables/iptables rule that drops packets with invalid conntrack state, but I don't recommend to do this. The step 3 is better solution.
+    * Step 3, ultimate solution. Use mark (don't confuse with connmark). The youtubeUnblock uses mark internally to avoid infinity packet loops (when the packet is sent by youtubeUnblock but on next step handled by itself). Currently it uses mark (1 << 15) = 32768. You should put iptables/nftables that ultimately accepts such marks at the very start of the filter OUTPUT chain: `iptables -I OUTPUT -m mark --mark 32768/32768 -j ACCEPT` or `nft insert rule inet fw4 output mark and 0x8000 == 0x8000 counter accept`.
+
 ## OpenWRT case
-The package is also compatible with routers. The router should be running by free opensource linux-based system such as [OpenWRT](https://openwrt.org/). You should cross-compile it under your host machine. Be ready for compilation errors and a lot of googling about it. It is not such a trivial process! You can get crosscompilation toolsuite compatible with your router from OpenWRT repositories. For example, I have ramips/mt76x8 based router so for me the toolsuite is on https://downloads.openwrt.org/releases/23.05.3/targets/ramips/mt76x8/ and called `openwrt-toolchain-23.05.3-ramips-mt76x8_gcc-12.3.0_musl.Linux-x86_64.tar.xz`. You can find out more about your router model on it's openwrt page. When you download the toolsuite, untar it somewhere. Now we are ready for compilation. My cross gcc asked me to create a staging dir for it and pass it as an environment variable. Also you should notice toolsuite packages and replace my make command with yours. ```STAGING_DIR=temp make CC=/usr/bin/mipsel-openwrt-linux-gcc LD=/usr/bin/mipsel-openwrt-linux-gcc AR=/usr/bin/mipsel-openwrt-linux-ar OBJDUMP=/usr/bin/mipsel-openwrt-linux-objdump NM=/usr/bin/mipsel-openwrt-linux-nm STRIP=/usr/bin/mipsel-openwrt-linux-strip CROSS_COMPILE_PLATFORM=mipsel-buildroot-linux-gnu```. Take a look at `CROSS_COMPILE_PLATFORM` It is required by autotools but I think it is not necessary. Anyways I put `mipsel-buildroot-linux-gnu` in here. For your model may be an [automake cross-compile manual](https://www.gnu.org/software/automake/manual/html_node/Cross_002dCompilation.html) will be helpful. When compilation is done, the binary file will be in build directory. Copy it to your router. Note that an ssh access is likely to be required to proceed. sshfs don't work on my model so I injected the application to the router via Software Upload Package page. It has given me an error, but also a `/tmp/upload.ipk` file which I copied in root directory, `chmod +x`-ed and run.
+The package is also compatible with routers. The router should be running by free opensource linux-based system such as [OpenWRT](https://openwrt.org/). You should cross-compile it under your host machine. Be ready for compilation errors and a lot of googling about it. It is not such a trivial process! You can get crosscompilation toolsuite compatible with your router from OpenWRT repositories. For example, I have ramips/mt76x8 based router so for me the toolsuite is on https://downloads.openwrt.org/releases/23.05.3/targets/ramips/mt76x8/ and called `openwrt-toolchain-23.05.3-ramips-mt76x8_gcc-12.3.0_musl.Linux-x86_64.tar.xz`. You can find out more about your router model on it's openwrt page. When you download the toolsuite, untar it somewhere. Now we are ready for compilation. My cross gcc asked me to create a staging dir for it and pass it as an environment variable. Also you should notice toolsuite packages and replace my make command with yours. ```STAGING_DIR=temp make CC=/usr/bin/mipsel-openwrt-linux-gcc LD=/usr/bin/mipsel-openwrt-linux-ld AR=/usr/bin/mipsel-openwrt-linux-ar OBJDUMP=/usr/bin/mipsel-openwrt-linux-objdump NM=/usr/bin/mipsel-openwrt-linux-nm STRIP=/usr/bin/mipsel-openwrt-linux-strip CROSS_COMPILE_PLATFORM=mipsel-buildroot-linux-gnu```. Take a look at `CROSS_COMPILE_PLATFORM` It is required by autotools but I think it is not necessary. Anyways I put `mipsel-buildroot-linux-gnu` in here. For your model may be an [automake cross-compile manual](https://www.gnu.org/software/automake/manual/html_node/Cross_002dCompilation.html) will be helpful. When compilation is done, the binary file will be in build directory. Copy it to your router. Note that an ssh access is likely to be required to proceed. sshfs don't work on my model so I injected the application to the router via Software Upload Package page. It has given me an error, but also a `/tmp/upload.ipk` file which I copied in root directory, `chmod +x`-ed and run.

 Now let's talk about a router configuration. I installed a normal iptables user-space app: `xtables-legacy iptables-zz-legacy` and kernel/iptables nfqueue extensions: `iptables-mod-nfqueue kmod-ipt-nfqueue` and add `iptables -t mangle -A FORWARD -p tcp -m tcp --dport 443 -j NFQUEUE --queue-num 537 --queue-bypass` rule. 

-Next step is to daemonize the application in openwrt. Copy youtubeUnblock.owrt to /etc/init.d/youtubeUnblock and put the program into /usr/bin/. (Don't forget to `chmod +x` both). Now run `/etc/init.d/youtubeUnblock start`. You can alo run `/etc/init.d/youtubeUnblock enable` to force OpenWRT autostart the program on boot. 
+If you prefer nftables, this should work: `nft add rule inet fw4 mangle_forward tcp dport 443 counter queue num 537 bypass`. Note that kmod-nft-queue should be installed.

+Also you can copy `owrt/537-youtubeUnblock.nft` to `/usr/share/nftables.d/ruleset-post/537-youtubeUnblock.nft` and run `/etc/init.d/firewall reload`. This will reload the nftables ruleset and automatically link 537-youtubeUnblock.nft with it.

-## Further development
-Please note that the application needs in further development. Some googlevideo servers may still be unabailable, some may drop out hello packets on Firefox while some may do so on Chrome. If you got in trouble try to disable GSO (Pass -DNOUSE_GSO as CC_FLAGS). Also you may set the program to use IP fragmentation instead of TCP (-DUSE_IP_FRAGMENTATION).
+Next step is to daemonize the application in openwrt. Copy `owrt/youtubeUnblock.owrt` to `/etc/init.d/youtubeUnblock` and put the program into /usr/bin/. (Don't forget to `chmod +x` both). Now run `/etc/init.d/youtubeUnblock start`. You can alo run `/etc/init.d/youtubeUnblock enable` to force OpenWRT autostart the program on boot, but I don't recommend this since if the packet has bug you may lose access to the router (I think you will be able to reset it with reset settings tricks documented for your router). 

-**If you have any questions/suggestions/problems feel free to open an issue.**
+## Performance 
+If you have bad performance you can queue to youtubeUnblock only first, say, 20 packets from the connection. To do so, use nftables conntrack packets counter: `nft add rule inet fw4 mangle_forward tcp dport 443 ct original "packets < 20" counter queue num 537 bypass`. For my 1 CPU core device it worked pretty well. This works because we do care about only first packets with ClientHello. We don't need to process others.
+
+The same behavior is also possible in iptables: `iptables -t mangle -A FORWARD -p tcp -m tcp --dport 443 -m connbytes --connbytes-dir original --connbytes-mode packets --connbytes 0:19 -j NFQUEUE --queue-num 537 --queue-bypass`. (The package iptables-mod-conntrack-extra is required for connbytes on OpenWRT)
+
+## If you have any questions/suggestions/problems feel free to open an issue.
--- a/config.h
+++ b/config.h
@ -0,0 +1,40 @@
+#define MAX_THREADS 16
+
+#ifndef THREADS_NUM
+#define THREADS_NUM 1
+#endif
+
+#if THREADS_NUM > MAX_THREADS
+#error "Too much threads"
+#endif
+
+#ifndef NOUSE_GSO
+#define USE_GSO
+#endif
+
+#define FRAG_STRAT_TCP	0
+#define FRAG_STRAT_IP	1
+#define FRAG_STRAT_NONE	2
+
+#define FRAGMENTATION_STRATEGY FRAG_STRAT_TCP
+
+#if FRAGMENTATION_STRATEGY == FRAG_STRAT_TCP
+	#define USE_TCP_SEGMENTATION
+#elif FRAGMENTATION_STRATEGY == FRAG_STRAT_IP
+	#define USE_IP_FRAGMENTATION
+#elif FRAGMENTATION_STRATEGY == FRAG_STRAT_NONE
+#endif 
+
+#define RAWSOCKET_MARK (1 << 15)
+
+#ifdef USE_SEG2_DELAY
+#define SEG2_DELAY 100
+#endif
+
+#ifndef NO_FAKE_SNI
+#define FAKE_SNI
+#endif
+
+#ifndef SILENT 
+#define DEBUG
+#endif
--- a/mangle.c
+++ b/mangle.c
@ -1,4 +1,5 @@
 #include "mangle.h"
+#include "raw_replacements.h"

 #ifdef KERNEL_SPACE
 #include <linux/printk.h>
@ -430,3 +431,42 @@ nextMessage:
 	return vrd;
 }

+int gen_fake_sni(const struct iphdr *iph, const struct tcphdr *tcph, 
+		 uint8_t *buf, uint32_t *buflen) {
+
+	if (iph == NULL || tcph == NULL || buf == NULL || buflen == NULL)
+		return -EINVAL;
+
+	int ip_len = iph->ihl * 4;
+	size_t data_len = sizeof(fake_sni);
+
+	size_t dlen = data_len + ip_len;
+
+	if (*buflen < dlen) 
+		return -ENOMEM;
+
+	memcpy(buf, iph, ip_len);
+	memcpy(buf + ip_len, fake_sni, data_len);
+	struct iphdr *niph = (struct iphdr *)buf;
+
+	niph->protocol = IPPROTO_TCP;
+	niph->tot_len = htons(dlen);
+
+	int ret = 0;
+	struct tcphdr *ntcph = (struct tcphdr *)(buf + ip_len);
+
+#ifdef KERNEL_SPACE
+	ntcph->dest = tcph->dest;
+	ntcph->source = tcph->source;
+#else 
+	ntcph->th_dport = tcph->th_dport;
+	ntcph->th_sport = tcph->th_sport;
+#endif 
+
+	nfq_ip_set_checksum(niph);
+	nfq_tcp_compute_checksum_ipv4(ntcph, niph);
+
+	*buflen = dlen;
+
+	return 0;
+}
--- a/mangle.h
+++ b/mangle.h
@ -1,8 +1,5 @@
 #ifndef YU_MANGLE_H
 #define YU_MANGLE_H
-#define RAWSOCKET_MARK 0xfc70
-
-#define DEBUG

 #ifdef KERNEL_SPACE
 #include <linux/types.h>
@ -61,4 +58,7 @@ int tcp4_payload_split(uint8_t *pkt, uint32_t buflen,
 		       struct iphdr **iph, uint32_t *iph_len,
 		       struct tcphdr **tcph, uint32_t *tcph_len,
 		       uint8_t **payload, uint32_t *plen);
+
+int gen_fake_sni(const struct iphdr *iph, const struct tcphdr *tcph, 
+		 uint8_t *buf, uint32_t *buflen);
 #endif /* YU_MANGLE_H */
--- a/owrt/537-youtubeUnblock.nft
+++ b/owrt/537-youtubeUnblock.nft
@ -0,0 +1,5 @@
+#!/usr/sbin/nft -f
+# This file 
+
+insert rule inet fw4 mangle_forward tcp dport 443 ct original packets < 20 counter queue num 537 bypass
+insert rule inet fw4 output mark and 0x8000 == 0x8000 counter accept
--- a/owrt/youtubeUnblock.owrt
+++ b/owrt/youtubeUnblock.owrt
--- a/raw_replacements.h
+++ b/raw_replacements.h
@ -0,0 +1,6 @@
+#ifndef RAW_REPLACEMENTS_H
+#define RAW_REPLACEMENTS_H
+
+const char fake_sni[] = "\276(\001\273\366\234|\335\213\222\023\330\200\030\001\366\350e\000\000\001\001\b\n}\355\267Hm/\217\347\026\003\001\004\316\001\000\004\312\003\003K+\272\314\340\306\374>dw%\f\223\346\225\270\270~\335\027\f\264\341H\267\357\303\216T\322[\371 \245\320\212V6\374\3706\232\0216B\325\273P\b\300>\0332>\362\323\033\322\301\204\022f8\223\214\000\"\023\001\023\003\023\002\300+\300/\314\251\314\250\300,\3000\300\n\300\t\300\023\300\024\000\234\000\235\000/\0005\001\000\004_\000\000\000\023\000\021\000\000\016www.google.com\000\027\000\000\377\001\000\001\000\000\n\000\016\000\f\000\035\000\027\000\030\000\031\001\000\001\001\000\v\000\002\001\000\000\020\000\v\000\t\bhttp/1.1\000\005\000\005\001\000\000\000\000\000\"\000\n\000\b\004\003\005\003\006\003\002\003\0003\000k\000i\000\035\000 \333C\212\234-\t\237#\202\\\231\311\022]\333\341t(\t\276U\373u\234\316J~,^|*Z\000\027\000A\004k\n\255\254\376X\226t\001;n~\033\034.\245\027\024\3762_\352$\374\346^f\fF,\201\275\263\336O\231\001\032\200\357dI\266y\031\323\311vR\232\004\r\366FT\004\335\326\356\256\230B\t\313\000*\000\000\000+\000\005\004\003\004\003\003\000\r\000\030\000\026\004\003\005\003\006\003\b\004\b\005\b\006\004\001\005\001\006\001\002\003\002\001\000-\000\002\001\001\000\034\000\002@\001\376\r\0029\000\000\001\000\003\344\000 \337\306\243\332Y\033\a\252\352\025\365Z\035\223\226\304\255\363\215G\356g\344%}7\217\033n\211^\201\002\017g\267\334\326OD}\336\341ZC\230\226'\225\313\357\211\\\242\273\030k\216\377U\315\206\2410\200\203\332Z\223\005\370\b\304\370f\017\200\023\241\223~?\270{\037b\312\001\270\227\366\356\352\002\314\351\006\237\241q\226\300\314\321o\247{\201\317\230}B\005T\3660\335\320\332r?S\217\tq\036\031\326I|\237]\311 c\f\024r\031\310W\373\257\314q)q\030\237\261\227\217Kd?\257'G\320\020\340\256ND\247\005\341\324\024OP>\370\350\270b\311wAj\t\311\213\365i\203\230x\207\354\245<\274\202\230c\v0Y\263\364\022\303a\200\022\031\314\271rl=\327\336\001\327\264\267\342\353\352=\354[u\224\260\257\034\004\232\023\226}\227\030e\221\"\350\207\027dId\324\305\362N:\035\307`\204\337\201;\221\320\266b\362hrH\345e\206\246%\006\020a4\3430\036\225\215\274\275\360Q&\271\237)\222uK\362\017o\220\226W\357\267#\357\v\023\354\213\2629\331\ad\005/~6k\000[\247\301\270\310qJ\004\303|m5\363\376Y\002\243}6\251x\024\331)GH\335\205rI\032\f\210\a\212\347]\271\030\347.\021\213\365\026\030\340/Ny\r\332\3577\3203\026iX}>\2507\327&XRXU!\017\270I\313\352\350^?\352Uss\017\266pF\222NI\245\307_\305#\361\352\243+-\266\317Q\036s\243\277\355{S&\023>\275\360\215\032V\237XOY\345u>\002\305\252T\354\035\327v{P\352M\233\366\221\270\377\251\261f+rF\201wL2W\266X\252\242X\2536I\337c\205uZ\254Fe\305h\t\371\376\216r\336Y\327h\347*\331\257-ZQ{(\336\226\206\017\037\036\021\341\027z\033\254\235\252\227\224\004?p\243\351\\\263\352\205\327#W\345\255\256\375\267bP\3047\363!*K\003t\212(\306\214P\215\3506j\025\375\213e\254s\000)\001\034\000\367\000\361\002\276W%\232?\326\223\277\211v\017\a\361\347\312N\226\024L\260v\210\271j\324[|\270\344\3773\321-\313b>~\310\253XIR\324)&;\033{g;)\344\255\226\370\347I\\y\020\324\360\211vC\310\226s\267|\273$\341\332\2045qh\245w\2255\214\316\030\255\301\326C\343\304=\245\231h`yd\000#s\002\370\374Z\0336\245\361\226\222\306\032k\2457\016h\314(R;\326T~EHH\352\307\023^\247\363\321`V\340\253Z\233\357\227I\373\337z\177\nv\261\252\371\017\226\223\345\005\315y4\b\236N0\2630\017\215c\305&L\260\346J\237\203Q(\335W\027|>\3553\275j\307?W5\3463kc\350\262C\361 \037w!\371}\214\"I\377|\331@a;\342\3566\312\272Z\327u7\204'\215YBLL\235\236\242\345\215\245T\211a\312\263\342\000! \221\202X$\302\317\203\246\207c{\231\330\264\324\\k\271\272\336\356\002|\261O\207\030+\367P\317\356";
+
+#endif /*RAW_REPLACEMENTS_H*/
--- a/uspace.mk
+++ b/uspace.mk
@ -3,11 +3,15 @@ BUILD_DIR := $(CURDIR)/build
 DEPSDIR := $(BUILD_DIR)/deps

 CC := gcc
-LD:=gcc
+CCLD := $(CC)
+LD := ld
 CFLAGS:=-Wall -Wpedantic -Wno-unused-variable -I$(DEPSDIR)/include -Os
 LDFLAGS:=-L$(DEPSDIR)/lib -static

-export CC LD CFLAGS LDFLAGS
+LIBNFNETLINK_CFLAGS := -I$(DEPSDIR)/include
+LIBNFNETLINK_LIBS := -L$(DEPSDIR)/lib
+LIBMNL_CFLAGS := -I$(DEPSDIR)/include
+LIBMNL_LIBS := -L$(DEPSDIR)/lib

 # PREFIX is environment variable, if not set default to /usr/local
 ifeq ($(PREFIX),)
@ -16,6 +20,7 @@ else
 	PREFIX := $(DESTDIR)
 endif

+export CC CCLD LD CFLAGS LDFLAGS LIBNFNETLINK_CFLAGS LIBNFNETLINK_LIBS LIBMNL_CFLAGS LIBMNL_LIBS

 APP:=$(BUILD_DIR)/youtubeUnblock

@ -45,23 +50,23 @@ prepare_dirs:
 	mkdir -p $(DEPSDIR)

 $(LIBNFNETLINK):
-	cd deps/libnfnetlink && ./autogen.sh && ./configure --prefix=$(DEPSDIR) $(if $(CROSS_COMPILE_PLATFORM),--host=$(CROSS_COMPILE_PLATFORM),)
+	cd deps/libnfnetlink && ./autogen.sh && ./configure --prefix=$(DEPSDIR) $(if $(CROSS_COMPILE_PLATFORM),--host=$(CROSS_COMPILE_PLATFORM),) --enable-static --disable-shared
 	$(MAKE) -C deps/libnfnetlink
 	$(MAKE) install -C deps/libnfnetlink
 	
 $(LIBMNL):
-	cd deps/libmnl && ./autogen.sh && ./configure --prefix=$(DEPSDIR) $(if $(CROSS_COMPILE_PLATFORM),--host=$(CROSS_COMPILE_PLATFORM),)
+	cd deps/libmnl && ./autogen.sh && ./configure --prefix=$(DEPSDIR) $(if $(CROSS_COMPILE_PLATFORM),--host=$(CROSS_COMPILE_PLATFORM),) --enable-static --disable-shared
 	$(MAKE) -C deps/libmnl
 	$(MAKE) install -C deps/libmnl

 $(LIBNETFILTER_QUEUE): $(LIBNFNETLINK) $(LIBMNL)
-	cd deps/libnetfilter_queue && ./autogen.sh && ./configure --prefix=$(DEPSDIR) $(if $(CROSS_COMPILE_PLATFORM),--host=$(CROSS_COMPILE_PLATFORM),)
+	cd deps/libnetfilter_queue && ./autogen.sh && ./configure --prefix=$(DEPSDIR) $(if $(CROSS_COMPILE_PLATFORM),--host=$(CROSS_COMPILE_PLATFORM),) --enable-static --disable-shared
 	$(MAKE) -C deps/libnetfilter_queue
 	$(MAKE) install -C deps/libnetfilter_queue

 $(APP): $(OBJS) $(LIBNETFILTER_QUEUE) $(LIBMNL)
-	@echo 'LD $(APP)'
-	@$(LD) $(OBJS) -o $(APP) -L$(DEPSDIR)/lib -lmnl -lnetfilter_queue
+	@echo 'CCLD $(APP)'
+	@$(CCLD) $(OBJS) -o $(APP) -L$(DEPSDIR)/lib -lmnl -lnetfilter_queue

 $(BUILD_DIR)/%.o: %.c $(LIBNETFILTER_QUEUE) $(LIBMNL)
 	@echo 'CC $@'
@ -78,7 +83,7 @@ install: all
 uninstall:
 	rm $(PREFIX)/bin/youtubeUnblock
 	rm $(PREFIX)/lib/systemd/system/youtubeUnblock.service
-	systemctl disable youtubeUnblock.service
+	-systemctl disable youtubeUnblock.service

 clean:
 	rm -rf $(BUILD_DIR)
--- a/youtubeUnblock.c
+++ b/youtubeUnblock.c
@ -24,29 +24,10 @@
 #include <linux/netfilter.h>
 #include <linux/if_ether.h>
 #include <sys/socket.h>
-
 #include <pthread.h>
+
 #include "mangle.h"
-
-#ifndef NOUSE_GSO
-#define USE_GSO
-#endif
-
-#ifndef USE_IP_FRAGMENTATION
-#define USE_TCP_SEGMENTATION
-#endif
-
-#define RAWSOCKET_MARK 0xfc70
-#define MAX_THREADS 16
-
-#ifndef THREADS_NUM
-#define THREADS_NUM 1
-#endif
-
-#if THREADS_NUM > MAX_THREADS
-#error "Too much threads"
-#endif
-
+#include "config.h"

 static struct {
 	uint32_t queue_start_num;
@ -176,7 +157,6 @@ static int close_raw_socket(void) {
 	return 0;
 }

-
 #define AVAILABLE_MTU 1384

 static int send_raw_socket(const uint8_t *pkt, uint32_t pktlen) {
@ -190,15 +170,20 @@ static int send_raw_socket(const uint8_t *pkt, uint32_t pktlen) {
 		uint8_t buff2[MNL_SOCKET_BUFFER_SIZE];
 		uint32_t buff2_size = MNL_SOCKET_BUFFER_SIZE;

-#ifdef USE_TCP_SEGMENTATION
+#if defined(USE_TCP_SEGMENTATION) || defined(RAWSOCK_TCP_FSTRAT)
 		if ((errno = tcp4_frag(pkt, pktlen, AVAILABLE_MTU-128, 
 			buff1, &buff1_size, buff2, &buff2_size)) < 0)
 			return -1;
-#else
+#elif defined(USE_IP_FRAGMENTATION) || defined(RAWSOCK_IP_FSTRAT)
 		if ((errno = ip4_frag(pkt, pktlen, AVAILABLE_MTU-128, 
 			buff1, &buff1_size, buff2, &buff2_size)) < 0)
 			return -1;
-
+#else
+		errno = EINVAL;
+		printf("send_raw_socket: Packet is too big but fragmentation is disabled! "
+			"Pass -DRAWSOCK_TCP_FSTRAT or -DRAWSOCK_IP_FSTRAT as CFLAGS "
+			"To enable it only for raw socket\n");
+		return -1;
 #endif

 		int sent = 0;
@ -287,8 +272,29 @@ static int fallback_accept_packet(uint32_t id, struct queue_data qdata) {
        return MNL_CB_OK;
 }

-static int process_packet(const struct packet_data packet, struct queue_data qdata) {

+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);
+	send_raw_socket(pkt, pktlen);
+
+	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;

@ -343,50 +349,93 @@ static int process_packet(const struct packet_data packet, struct queue_data qda
 #endif
 		}
 		
+#ifdef FAKE_SNI
+		uint8_t fake_sni[MNL_SOCKET_BUFFER_SIZE];
+		uint32_t fsn_len = MNL_SOCKET_BUFFER_SIZE;
+#endif
+
 		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 *)ip_header);
+		nfq_tcp_compute_checksum_ipv4(
+			(struct tcphdr *)tcph, (struct iphdr *)ip_header);

-#ifdef USE_TCP_SEGMENTATION
-		size_t ipd_offset = vrd.sni_offset;
-		size_t mid_offset = ipd_offset + vrd.sni_len / 2;
-
-		if ((errno = tcp4_frag(raw_payload, raw_payload_len, 
-			 mid_offset, frag1, &f1len, frag2, &f2len)) < 0) {
-			errno *= -1;
-			perror("tcp4_frag");
+#ifdef FAKE_SNI
+		ret = gen_fake_sni(ip_header, tcph, fake_sni, &fsn_len);
+		if (ret < 0) {
+			errno = -ret;
+			perror("gen_fake_sni");
 			goto fallback;
 		}

-		if ((send_raw_socket(frag2, f2len) < 0) || 
-			(send_raw_socket(frag1, f1len) < 0)) {
-			perror("raw frags send");
+		ret = send_raw_socket(fake_sni, fsn_len);
+		if (ret < 0) {
+			errno = -ret;
+			perror("send fake sni");
+			goto fallback;
+		}
+#endif
+
+
+#if defined(USE_TCP_SEGMENTATION)
+		size_t ipd_offset = vrd.sni_offset;
+		size_t 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 send_verd;
 		}

-#else
-		// TODO: Implement compute of tcp checksum
-		// GSO may turn kernel to not compute the tcp checksum.
-		// Also it will never be meaningless to ensure the 
-		// checksum is right.
-		// nfq_tcp_compute_checksum_ipv4(tcph, ip_header);
-
+#elif defined(USE_IP_FRAGMENTATION)
 		size_t ipd_offset = ((char *)data - (char *)tcph) + vrd.sni_offset;
 		size_t mid_offset = ipd_offset + vrd.sni_len / 2;
 		mid_offset += 8 - mid_offset % 8;

-		if ((errno = ip4_frag(raw_payload, raw_payload_len, 
+		if ((ret = ip4_frag(raw_payload, raw_payload_len, 
 			 mid_offset, frag1, &f1len, frag2, &f2len)) < 0) {
-			errno *= -1;
+			errno = -ret;
 			perror("ip4_frag");
-			goto fallback;
+			goto send_verd;
 		}

-		if ((send_raw_socket(frag2, f2len) < 0) || 
-			(send_raw_socket(frag1, f1len) < 0)) {
-			perror("raw frags send");
+#else
+		ret = send_raw_socket(raw_payload, raw_payload_len);
+		if (ret < 0) {
+			errno = -ret;
+			perror("raw pack send");
+		}
+		goto send_verd;
+#endif
+
+		ret = send_raw_socket(frag2, f2len);
+		if (ret < 0) {
+			errno = -ret;
+			perror("raw frags send: frag2");
+
+			goto send_verd;
+		}
+		
+#ifdef SEG2_DELAY
+		struct dps_t *dpdt = malloc(sizeof(struct dps_t));
+		dpdt->pkt = malloc(f1len);
+		dpdt->timer = 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 send_verd;
 		}

 #endif
@ -404,6 +453,7 @@ static int process_packet(const struct packet_data packet, struct queue_data qda
 	}
 */

+send_verd:
        if (mnl_socket_sendto(*qdata._nl, verdnlh, verdnlh->nlmsg_len) < 0) {
                perror("mnl_socket_send");
 		
@ -452,7 +502,7 @@ static int queue_cb(const struct nlmsghdr *nlh, void *data) {

 	if (attr[NFQA_MARK] != NULL) {
 		// Skip packets sent by rawsocket to escape infinity loop.
-		if (ntohl(mnl_attr_get_u32(attr[NFQA_MARK])) == 
+		if ((ntohl(mnl_attr_get_u32(attr[NFQA_MARK])) & RAWSOCKET_MARK) == 
 			RAWSOCKET_MARK) {
 			return fallback_accept_packet(packet.id, *qdata);
 		}
@ -564,10 +614,20 @@ int main(int argc, const char *argv[]) {
 		exit(EXIT_FAILURE);
 	}

-#ifdef USE_TCP_SEGMENTATION
-	printf("Using TCP segmentation!\n");
+#if defined(USE_TCP_SEGMENTATION)
+	printf("Using TCP segmentation\n");
+#elif defined(USE_IP_FRAGMENTATION)
+	printf("Using IP fragmentation\n");
 #else
-	printf("Using IP fragmentation!\n");
+	printf("SNI fragmentation is disabled\n");
+#endif 
+
+#ifdef SEG2_DELAY
+	printf("Some outgoing googlevideo request segments will be delayed for %d ms as of SEG2_DELAY define\n", SEG2_DELAY);
+#endif 
+
+#ifdef FAKE_SNI
+	printf("Fake SNI will be sent before each googlevideo request\n");
 #endif 

 #ifdef USE_GSO
@ -579,6 +639,8 @@ int main(int argc, const char *argv[]) {
 		exit(EXIT_FAILURE);
 	}

+
+
 #if THREADS_NUM == 1
 	struct queue_conf tconf = {
 		.i = 0,
@ -600,10 +662,11 @@ int main(int argc, const char *argv[]) {
 	}

 	void *res;
+	struct queue_res *qres
 	for (int i = 0; i < config.threads; i++) {
 		pthread_join(threads[i], &res);

-		struct queue_res *qres = res;
+		qres = res;
 	}
 #endif

--- a/youtubeUnblock.service
+++ b/youtubeUnblock.service
@ -5,7 +5,9 @@ Description=youtubeUnblock
 StandardError=journal
 StandardOutput=journal
 StandardInput=null
+ExecStartPre=iptables -t mangle -A OUTPUT -p tcp --dport 443 -j NFQUEUE --queue-num 537 --queue-bypass
 ExecStart=$(PREFIX)/bin/youtubeUnblock 537
+ExecStop=iptables -t mangle -D OUTPUT -p tcp --dport 443 -j NFQUEUE --queue-num 537 --queue-bypass

 [Install]
 WantedBy=multi-user.target