ts-warp.c: -D 0..512 DPI bypass fragment sizing

CHANGELOG.md

@@ -1,5 +1,8 @@
 # CHANGELOG
 
+* **2024.08.23    Current**
+  *`ts-warp.c`: `-D 0..512` DPI bypass fragment size by default 0 - disabled; To enable use a positive value, e.g., 2
+
 * **2024.08.15    ts-warp-1.5.5, gui-warp-1.0.25 (gui-warp-v1.0.30-mac), ns-warp-1.0.7**
   * `ts-warp.c`, `http.c`: Deep Packet Inspections bypass. Option `-D` to disable it.
   * `ts-warp.c`: Internal proxy servers allowed making direct connection to destinations

README.md

@@ -201,13 +201,17 @@ Note, Python 3 interpreter with `tkinter` support is required to run the GUI fro
 Check [releases](https://github.com/mezantrop/ts-warp/releases) and download macOS standalone precompiled application.
 Read related [README.md](gui/ports/macOS/README.md) for information and instructions.
 
-### Experimental Deep Packet Inspections bypass
+### Experimental Deep Packet Inspections bypass (обход замедления/блокировки, например, YouTube)
 
 According to [SpoofDPI](https://github.com/xvzc/SpoofDPI?tab=readme-ov-file#https) project, sending the first 1 byte
 of a request to the server, and then sending the rest of the data can help to bypass Deep Packet Inspections of HTTPS.
 
-`TS-Warp` has the feature enabled by default. Just use TS-Warp in `Transparent` mode, or point your browser to `TS-Warp`
-Internal `HTTP(S)` proxy at default `127.0.0.1:8080` or `SOCKS5` proxy at `127.0.0.1:7080`.
+To bypass DPI, start TS-Warp with `-D 0..512` flag, e.g., `-D 2` to enable packet fragmentation, then use TS-Warp
+normally in `Transparent` mode, or point your browser to `TS-Warp` Internal `HTTP(S)` proxy at `127.0.0.1:8080` or
+`SOCKS5` proxy at `127.0.0.1:7080`.
+
+If you use macOS, download from [releases](https://github.com/mezantrop/ts-warp/releases) a precompiled `GUI-Warp`
+macOS application with DPI bypass option already enabled!
 
 ### Contacts
 

http.c

@@ -120,9 +120,9 @@ int http_client_request(chs cs, struct sockaddr_storage *daddr, char *user, char
     switch (cs.t) {
         case CHS_SOCKET:
             if (sdpi) {
-                printl(LOG_VERB, "Trying to bypass Deep Packet Inspections");
+                printl(LOG_VERB, "Trying to bypass Deep Packet Inspections for HTTP proxy. Fragment size: [%d]", sdpi);
 
-                if (send(cs.s, r, 1, 0) == -1 || send(cs.s, r + 1, l - 1, 0) == -1) {
+                if (send(cs.s, r, sdpi, 0) == -1 || send(cs.s, r + sdpi, l - sdpi, 0) == -1) {
                     printl(LOG_CRIT, "SDPI: Unable to send a request to the HTTP server via socket");
                     return 1;
                 }

network.h

@@ -71,6 +71,9 @@
 
 #define INET_ADDRPORTSTRLEN INET6_ADDRSTRLEN + 6    /* MAX: ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff + ':' + '65535' */
 
+#define SDPI_FRAGMENTSZ_MAX 512                     /* Maximum fragment size to bypass DPI */
+
+
 /* -- Socket conversion macros -------------------------------------------------------------------------------------- */
 #define SA_FAMILY(sa)  ((struct sockaddr *)&sa)->sa_family
 

ts-warp.c

@@ -127,7 +127,7 @@ All parameters are optional:
   -f              Force start
 
   -u user         A user to run ts-warp, default: nobody
-  -D              Do not try spoofing Deep Packet Inspections
+  -D 0..512       Deep Packet Inspections bypass fragment size. Default: 0 - disabled. Set any value, e.g., 2 to enable
 
   -h              This message */
 
@@ -142,7 +142,9 @@ All parameters are optional:
     int l_flg = 0;                                                      /* User didn't set the log file */
     int d_flg = 0;                                                      /* Daemon mode */
     int f_flg = 0;                                                      /* Force start */
-    int sdpi = 1;                                                       /* Try bypassing DPI */
+
+    int sdpi = 0;                                                       /* Packet fragment size: default 0. Set any
+                                                                        positive value to try tricking DPI */
     /* According to https://github.com/xvzc/SpoofDPI?tab=readme-ov-file#https sending the first 1 byte of a request
     to the server, and then sending the rest of the data can help to bypass Deep Packet Inspections of HTTPS */
 
@@ -181,7 +183,7 @@ All parameters are optional:
     #endif
 
 
-    while ((flg = getopt(argc, argv, "T:S:H:c:l:v:t:dp:fu:Dh")) != -1)
+    while ((flg = getopt(argc, argv, "T:S:H:c:l:v:t:dp:fu:D:h")) != -1)
         switch(flg) {
             case 'T':                                                   /* Internal Transparent server IP/name */
                 taddr = strsep(&optarg, ":");                           /* IP:PORT */
@@ -238,12 +240,16 @@ All parameters are optional:
             break;
 
             case 'D':
-                sdpi = 0;
+                sdpi = toint(optarg);
+                if (sdpi < 0 || sdpi > SDPI_FRAGMENTSZ_MAX) {
+                    fprintf(stderr, "Fatal: wrong -D value:[%s]\n", optarg);
+                    usage(1);
+                }
             break;
 
             case 'h':                                                   /* Help */
             default:
-                (void)usage(0);
+                usage(0);
         }
 
     if (!taddr[0]) taddr = LISTEN_DEFAULT;
@@ -662,6 +668,9 @@ All parameters are optional:
 
             if (!s_ini && isock == Tsock) {
                 /* -- No proxy server found for the destination IP -------------------------------------------------- */
+                close(Tsock);
+                if (Ssock != -1) close(Ssock);
+                if (Hsock != -1) close(Hsock);
                 printl(LOG_INFO, "No proxy server is defined for the destination: [%s]", inet2str(&daddr.ip_addr, buf));
 
                 if ((daddr.ip_addr.ss_family == AF_INET &&
@@ -1300,19 +1309,18 @@ All parameters are optional:
                             }
 
                             if (sdpi && rec > 1) {
-                                printl(LOG_VERB, "Trying to bypass Deep Packet Inspections");
+                                printl(LOG_VERB, "Trying to bypass Deep Packet Inspections. Fragment size: [%d]", sdpi);
 
-                                if ((snd = send(ssock.s, buf, 1, 0)) == -1) {
+                                if ((snd = send(ssock.s, buf, sdpi < rec ? sdpi : rec, 0)) == -1) {
                                     printl(LOG_CRIT, "Error sending data to proxy server");
                                     break;
                                 }
-                                int _snd = send(ssock.s, buf + 1, rec - 1, 0);
+                                int _snd = send(ssock.s, buf + snd, rec - snd, 0);
                                 if (_snd == -1) {
                                     printl(LOG_CRIT, "Error sending data to proxy server");
                                     break;
                                 }
                                 snd += _snd;
-                                sdpi = 0;                                           /* No need to split more packets */
                             } else
                                 while ((snd = send(ssock.s, buf, rec, 0)) == 0) {
                                     printl(LOG_CRIT, "C:[0] -> S:[0] bytes");
@@ -1476,7 +1484,7 @@ All parameters are optional:\n\
   -f\t\t    Force start\n\
   \n\
   -u user\t    A user to run ts-warp, default: %s. Note, this option has no effect on macOS\n\
-  -D\t\t    Do not try bypass Deep Packet Inspections\n\
+  -D 0..512\t  Deep Packet Inspections bypass fragment size. Default: 0 - disabled. Set any value, e.g., 2 to enable\n\
   \n\
   -h\t\t    This message\n\n",
     PROG_NAME, PROG_VERSION, INI_FILE_NAME, LOG_FILE_NAME, LOG_LEVEL_DEFAULT, PID_FILE_NAME, RUNAS_USER);