From e203aacc2cd6a303d4cb2022915a26a476666ce4 Mon Sep 17 00:00:00 2001
From: ruti <>
Date: Wed, 14 Aug 2024 15:20:35 +0300
Subject: [PATCH] Set TTL before connect

---
 desync.c |  8 +-------
 desync.h |  4 ++++
 extend.c | 14 ++++++++++++++
 extend.h |  2 ++
 proxy.c  | 15 ++++++++-------
 5 files changed, 29 insertions(+), 14 deletions(-)

diff --git a/desync.c b/desync.c
index a87496a..8d81f1b 100644
--- a/desync.c
+++ b/desync.c
@@ -39,7 +39,7 @@
 #include "error.h"
 
 
-static inline int get_family(struct sockaddr *dst)
+int get_family(struct sockaddr *dst)
 {
     if (dst->sa_family == AF_INET6) {
         struct sockaddr_in6 *d6 = (struct sockaddr_in6 *)dst;
@@ -429,12 +429,6 @@ ssize_t desync(int sfd, char *buffer, size_t bfsize,
             lp = pos + 5;
         }
     }
-    // set custom TTL
-    if (params.custom_ttl) {
-        if (setttl(sfd, params.def_ttl, fa) < 0) {
-            return -1;
-        }
-    }
     // desync
     long lp = offset;
     
diff --git a/desync.h b/desync.h
index a1a67db..2e456df 100644
--- a/desync.h
+++ b/desync.h
@@ -14,6 +14,10 @@ ssize_t desync(int sfd, char *buffer, size_t bfsize, ssize_t n, ssize_t offset,
 
 ssize_t desync_udp(int sfd, char *buffer, size_t bfsize, ssize_t n, struct sockaddr *dst, int dp_c);
 
+int get_family(struct sockaddr *dst);
+
+int setttl(int fd, int ttl, int family);
+
 struct tcpi {
     uint8_t state;
     uint8_t r[3];
diff --git a/extend.c b/extend.c
index ac90b02..a37acc6 100644
--- a/extend.c
+++ b/extend.c
@@ -110,6 +110,20 @@ int connect_hook(struct poolhd *pool, struct eval *val,
 }
 
 
+int socket_mod(int fd, struct sockaddr *dst)
+{
+    if (params.custom_ttl) {
+        if (setttl(fd, params.def_ttl, get_family(dst)) < 0) {
+            return -1;
+        }
+    }
+    if (params.protect_path) {
+        return protect(fd, params.protect_path);
+    }
+    return 0;
+}
+
+
 int reconnect(struct poolhd *pool, struct eval *val, int m)
 {
     struct eval *client = val->pair;
diff --git a/extend.h b/extend.h
index 22d8ed8..36bce5b 100644
--- a/extend.h
+++ b/extend.h
@@ -5,6 +5,8 @@
 
 #include "proxy.h"
 
+int socket_mod(int fd, struct sockaddr *dst);
+
 int connect_hook(struct poolhd *pool, struct eval *val, 
         struct sockaddr_ina *dst, int next);
         
diff --git a/proxy.c b/proxy.c
index 88539e4..bad27c7 100644
--- a/proxy.c
+++ b/proxy.c
@@ -331,8 +331,7 @@ int create_conn(struct poolhd *pool,
         uniperror("socket");  
         return -1;
     }
-    if (params.protect_path 
-            && protect(sfd, params.protect_path) < 0) {
+    if (socket_mod(sfd, &addr.sa) < 0) {
         close(sfd);
         return -1;
     }
@@ -416,11 +415,6 @@ int udp_associate(struct poolhd *pool,
         uniperror("socket");  
         return -1;
     }
-    if (params.protect_path 
-            && protect(ufd, params.protect_path) < 0) {
-        close(ufd);
-        return -1;
-    }
     if (params.baddr.sin6_family == AF_INET6) {
         int no = 0;
         if (setsockopt(ufd, IPPROTO_IPV6,
@@ -448,6 +442,10 @@ int udp_associate(struct poolhd *pool,
             del_event(pool, pair);
             return -1;
         }
+        if (socket_mod(ufd, &addr.sa) < 0) {
+            del_event(pool, pair);
+            return -1;
+        }
         pair->in6 = addr.in6;
     }
     //
@@ -695,6 +693,9 @@ int on_udp_tunnel(struct eval *val, char *buffer, size_t bfsize)
                     uniperror("connect");
                     return -1;
                 }
+                if (socket_mod(val->pair->fd, &addr.sa) < 0) {
+                    return -1;
+                }
                 val->pair->in6 = addr.in6;
             }
             ns = udp_hook(val->pair, data + offs, bfsize - offs, n - offs,