From 380f91058c274fd51a5849dbe5ce5a1964d5bc0b Mon Sep 17 00:00:00 2001
From: ruti <>
Date: Mon, 29 Jul 2024 16:08:35 +0300
Subject: [PATCH] Port filter

---
 extend.c | 21 ++++++++++++++-------
 main.c   | 24 ++++++++++++++++++++++--
 params.h |  1 +
 proxy.c  |  2 +-
 4 files changed, 38 insertions(+), 10 deletions(-)

diff --git a/extend.c b/extend.c
index 8b71b0d..92abe93 100644
--- a/extend.c
+++ b/extend.c
@@ -90,6 +90,13 @@ int mode_add_get(struct sockaddr_ina *dst, int m)
 }
 
 
+inline bool check_port(uint16_t *p, struct sockaddr_in6 *dst)
+{
+    return (dst->sin6_port >= p[0] 
+            && dst->sin6_port <= p[1]);
+}
+
+
 int connect_hook(struct poolhd *pool, struct eval *val, 
         struct sockaddr_ina *dst, int next)
 {
@@ -355,8 +362,9 @@ int on_desync(struct poolhd *pool, struct eval *val,
     if (!m) for (; m < params.dp_count; m++) {
         struct desync_params *dp = &params.dp[m];
         if (!dp->detect &&
-                (!dp->hosts || check_host(dp->hosts, val)) &&
-                (!dp->proto || check_proto_tcp(dp->proto, val))) {
+                (!dp->pf[0] || check_port(dp->pf, &val->pair->in6)) &&
+                (!dp->proto || check_proto_tcp(dp->proto, val)) &&
+                (!dp->hosts || check_host(dp->hosts, val))) {
             break;
         }
     }
@@ -379,16 +387,15 @@ ssize_t udp_hook(struct eval *val,
     if (!m) for (; m < params.dp_count; m++) {
         struct desync_params *dp = &params.dp[m];
         if (!dp->detect && 
-                (!dp->proto || (dp->proto & IS_UDP))) {
+                (!dp->proto || (dp->proto & IS_UDP)) &&
+                (!dp->pf[0] || check_port(dp->pf, &dst->in6))) {
             break;
         }
     }
     if (m >= params.dp_count) {
         return -1;
-    }
-    val->attempt = m;
-    
-    return desync_udp(val->fd, buffer, bfsize, n, &dst->sa, 0);
+    }   
+    return desync_udp(val->fd, buffer, bfsize, n, &dst->sa, m);
 }
 
 
diff --git a/main.c b/main.c
index 487297d..a8e38af 100644
--- a/main.c
+++ b/main.c
@@ -84,7 +84,8 @@ const char help_text[] = {
     "    -T, --timeout <sec>       Timeout waiting for response, after which trigger auto\n"
     #endif
     "    -K, --proto <t,h,u>       Protocol whitelist: tls,http,udp\n"
-    "    -H, --hosts <file|:str>   Hosts whitelist\n"
+    "    -H, --hosts <file|:str>   Hosts whitelist, filename or :string\n"
+    "    -V, --pf <port[-portr]>   Port or port range whitelist\n"
     "    -s, --split <n[+s]>       Split packet at n\n"
     "                              +s - add SNI offset\n"
     "                              +h - add HTTP Host offset\n"
@@ -130,6 +131,7 @@ const struct option options[] = {
     #endif
     {"proto",         1, 0, 'K'},
     {"hosts",         1, 0, 'H'},
+    {"pf",            1, 0, 'V'},
     {"split",         1, 0, 's'},
     {"disorder",      1, 0, 'd'},
     {"oob",           1, 0, 'o'},
@@ -737,6 +739,24 @@ int main(int argc, char **argv)
                 dp->udp_fake_count = val;
             break;
             
+        case 'V':
+            val = strtol(optarg, &end, 0);
+            if (val <= 0 || val > USHRT_MAX)
+                invalid = 1;
+            else {
+                dp->pf[0] = htons(val);
+                if (*end == '-') {
+                    val = strtol(end + 1, &end, 0);
+                    if (val <= 0 || val > USHRT_MAX)
+                        invalid = 1;
+                }
+                if (*end)
+                    invalid = 1;
+                else
+                    dp->pf[1] = htons(val);
+            }
+            break;
+            
         case 'g':
             val = strtol(optarg, &end, 0);
             if (val <= 0 || val > 255 || *end)
@@ -780,7 +800,7 @@ int main(int argc, char **argv)
         clear_params();
         return -1;
     }
-    if (dp->hosts || dp->proto) {
+    if (dp->hosts || dp->proto || dp->pf[0]) {
         dp = add((void *)&params.dp,
             &params.dp_count, sizeof(struct desync_params));
         if (!dp) {
diff --git a/params.h b/params.h
index ffe3c65..673a112 100644
--- a/params.h
+++ b/params.h
@@ -68,6 +68,7 @@ struct desync_params {
     int proto;
     int detect;
     struct mphdr *hosts;
+    uint16_t pf[2];
     
     char *file_ptr;
     ssize_t file_size;
diff --git a/proxy.c b/proxy.c
index 092d8e0..f4bdc3e 100644
--- a/proxy.c
+++ b/proxy.c
@@ -695,7 +695,7 @@ int on_udp_tunnel(struct eval *val, char *buffer, size_t bfsize)
                 }
                 val->pair->in6 = addr.in6;
             }
-            ns = udp_hook(val, data + offs, bfsize - offs, n - offs, 
+            ns = udp_hook(val->pair, data + offs, bfsize - offs, n - offs, 
                 (struct sockaddr_ina *)&val->pair->in6);
         }
         else {