openvpn patch to help with clients which can't use tunnelblick patch (#…

…64)

* added dpi patch

* added openvpn patch to overcome DPI w/o patching the client

added openvpn patch to overcome DPI w/o patching the client

Dockerfile

@@ -72,6 +72,41 @@ RUN <<-"EOT" bash -ex
         wget "https://raw.githubusercontent.com/Tunnelblick/Tunnelblick/master/third_party/sources/openvpn/openvpn-$OPENVPN_VER/patches/$patch"
         git apply "$patch"
     done
+# Patch to overcome DPI start (works only for UDP connections, taken from https://github.com/GubernievS/AntiZapret-VPN/blob/main/setup/root/patch-openvpn.sh
+    sed -i '/link_socket_write_udp(struct link_socket \*sock/,/\/\* write a TCP or UDP packet to link \*\//c\
+    link_socket_write_udp(struct link_socket *sock,\
+                          struct buffer *buf,\
+                          struct link_socket_actual *to)\
+    {\
+        uint16_t stuffing_sent = 0;\
+        uint8_t opcode = *BPTR(buf) >> 3;\
+    if (opcode == 7 || opcode == 8 || opcode == 10)\
+    {\
+        uint8_t stuffing_data[] = {0x01, 0x00, 0x00, 0x00, 0x01};\
+        size_t stuffing_len = sizeof(stuffing_data);\
+        struct buffer stuffing_buf = clone_buf(buf);\
+        buf_clear(&stuffing_buf);\
+        buf_write(&stuffing_buf, stuffing_data, stuffing_len);\
+        for (int i=0; i<100; i++)\
+        {\
+    #ifdef _WIN32\
+            stuffing_sent =+ link_socket_write_win32(sock, &stuffing_buf, to);\
+    #else\
+            stuffing_sent =+ link_socket_write_udp_posix(sock, &stuffing_buf, to);\
+    #endif\
+        }\
+        free_buf(&stuffing_buf);\
+    }\
+    #ifdef _WIN32\
+        stuffing_sent =+ link_socket_write_win32(sock, buf, to);\
+    #else\
+        stuffing_sent =+ link_socket_write_udp_posix(sock, buf, to);\
+    #endif\
+        return stuffing_sent;\
+    }\
+    \
+    \/\* write a TCP or UDP packet to link \*\/' "/opt/openvpn_install/openvpn-$OPENVPN_VER/src/openvpn/socket.h"
+# Patch to overcome DPI end
 
     ./configure --enable-static=yes --enable-shared  --enable-systemd=yes --disable-lzo --disable-debug --disable-plugin-auth-pam --disable-dependency-tracking
     make -j$(nproc)