尝试将ss-redir的转发改为IPv6转发

目前`IP6T_SO_ORIGINAL_DST`这个东西上边，不能正确获取原始目标地址。尝试`curl bt.byr.cn`，前面一部分地址可以看到是`a:50::2001:da8:215:4078`，但是格式完全不对，内容也不全，正确的地址应该是`2001:da8:215:4078:250:56ff:fe97:654d`。估计是某些针对IPv4的设定没有改过来。改日再看。
另外吐槽一下原版毫无注释的代码……

src/redir.c

@@ -37,7 +37,9 @@
 #include <time.h>
 #include <unistd.h>
 #include <limits.h>
+#include <linux/if.h>
 #include <linux/netfilter_ipv4.h>
+#include <linux/netfilter_ipv6/ip6_tables.h>
 
 #ifdef HAVE_CONFIG_H
 #include "config.h"
@@ -58,16 +60,16 @@
 #define BUF_SIZE 2048
 #endif
 
-int getdestaddr(int fd, struct sockaddr_in *destaddr)
+int getdestaddr( struct listen_ctx * listener, struct sockaddr_in *destaddr)
 {
-    socklen_t socklen = sizeof(*destaddr);
-    int error;
+/*    socklen_t socklen = sizeof(*destaddr);
+    int error=0;
 
-    error = getsockopt(fd, SOL_IP, SO_ORIGINAL_DST, destaddr, &socklen);
+ //   error = getsockopt(listener->fd, (listener->local.isIPv6()?SOL_IP6:SOL_IP), (listener->local.isIPv6()?IP6T_SO_ORIGINAL_DST:SO_ORIGINAL_DST), destaddr, &socklen);
     if (error)
     {
         return -1;
-    }
+    }*/
     return 0;
 }
 
@@ -104,6 +106,7 @@ int create_and_bind(const char *addr, const char *port)
 
         int opt = 1;
         setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
+//        setsockopt(listen_sock, IPPROTO_IPV6, SO_REUSEADDR, &opt, sizeof(opt));
         setsockopt(listen_sock, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof(opt));
 #ifdef SO_NOSIGPIPE
         setsockopt(listen_sock, SOL_SOCKET, SO_NOSIGPIPE, &opt, sizeof(opt));
@@ -398,9 +401,9 @@ static void remote_send_cb (EV_P_ ev_io *w, int revents)
 
             // handle IP V4 only
             size_t in_addr_len = sizeof(struct in_addr);
-            memcpy(ss_addr_to_send + addr_len, &server->destaddr.sin_addr, in_addr_len);
+            memcpy(ss_addr_to_send + addr_len, &server->destaddr.sin6_addr, in_addr_len);
             addr_len += in_addr_len;
-            memcpy(ss_addr_to_send + addr_len, &server->destaddr.sin_port, 2);
+            memcpy(ss_addr_to_send + addr_len, &server->destaddr.sin6_port, 2);
             addr_len += 2;
             ss_addr_to_send = ss_encrypt(BUF_SIZE, ss_addr_to_send, &addr_len, server->e_ctx);
             if (ss_addr_to_send == NULL)
@@ -612,7 +615,7 @@ void close_and_free_server(EV_P_ struct server *server)
 static void accept_cb (EV_P_ ev_io *w, int revents)
 {
     struct listen_ctx *listener = (struct listen_ctx *)w;
-    struct sockaddr_in destaddr;
+    struct sockaddr_in6 destaddr;
     int err;
 
     int clientfd = accept(listener->fd, NULL, NULL);
@@ -622,7 +625,18 @@ static void accept_cb (EV_P_ ev_io *w, int revents)
         return;
     }
 
-    err = getdestaddr(clientfd, &destaddr);
+    //err = getdestaddr(listener, &destaddr);
+    printf("Connet server %s, port %s.\n",listener->remote_addr->host,listener->remote_addr->port);
+    printf("%d %s\n",listener->sock.sa_family,listener->sock.sa_data);
+    socklen_t socklen = sizeof(destaddr);
+    //err = getsockopt(listener->fd, (listener->local.isIPv6()?SOL_IP6:SOL_IP), (listener->local.isIPv6()?IP6T_SO_ORIGINAL_DST:SO_ORIGINAL_DST), destaddr, &socklen);
+    err = getsockopt(clientfd, IPPROTO_IPV6, IP6T_SO_ORIGINAL_DST, &destaddr, &socklen);
+    //
+   char str[INET6_ADDRSTRLEN];
+   inet_ntop(AF_INET6, &destaddr, str, INET6_ADDRSTRLEN);
+   printf("%s\n", str);
+
+  
     if (err)
     {
         ERROR("getdestaddr");

src/redir.h

@@ -51,7 +51,7 @@ struct server
     ssize_t buf_len;
     ssize_t buf_idx;
     char *buf; // server send from, remote recv into
-    struct sockaddr_in destaddr;
+    struct sockaddr_in6 destaddr;
     struct enc_ctx *e_ctx;
     struct enc_ctx *d_ctx;
     struct server_ctx *recv_ctx;