TSG-8345,修复tamper策略ssh命中后仍正常登陆问题

src/tsg_action.cpp

@@ -729,6 +729,33 @@ static unsigned char do_action_tamper(const struct streaminfo *a_stream, Maat_ru
         return do_action_drop(a_stream, p_result, user_region, protocol, user_data);
     }
 
+    struct tcpall_context * _context=(struct tcpall_context *)get_struct_project(a_stream, g_tsg_para.tcpall_project_id);
+    if(_context==NULL)
+    {
+        _context=(struct tcpall_context *)dictator_malloc(a_stream->threadnum, sizeof(struct tcpall_context));
+        memset(_context, 0, sizeof(struct tcpall_context));
+        _context->method_type=TSG_METHOD_TYPE_TAMPER;
+
+        set_struct_project(a_stream, g_tsg_para.tcpall_project_id, (void *)_context);
+    }else{
+        if(_context->method_type == TSG_METHOD_TYPE_UNKNOWN)
+        {
+            _context->method_type=TSG_METHOD_TYPE_TAMPER;
+        }
+        else
+        {
+            //to do error log 
+            //_context->method_type                                                                                            
+			MESA_handle_runtime_log(g_tsg_para.logger,
+                                    RLOG_LV_DEBUG,
+                                    __FUNCTION__,
+                                    "_context->method_type : %d",
+                                    _context->method_type);
+	
+            return STATE_GIVEME;
+        }
+    }
+
     return send_tamper_xxx(a_stream, user_data);
 }
 

src/tsg_entry.cpp

@@ -1743,6 +1743,14 @@ static unsigned char tsg_master_all_entry(const struct streaminfo *a_stream, uns
 					state|=APP_STATE_GIVEME|APP_STATE_DROPPKT;
 				}
 				break;
+            case    TSG_METHOD_TYPE_TAMPER:
+                ret = send_tamper_xxx(a_stream, a_packet);
+                if(ret==STATE_DROPPKT){
+                    state|=APP_STATE_GIVEME|APP_STATE_DROPPKT;
+                }else{
+                    state=APP_STATE_GIVEME;
+                }
+                break;
 			default:
 				break;
 		}

src/tsg_tamper.cpp

@@ -5,6 +5,7 @@
 #include <time.h>
 
 #include "tsg_entry.h"
+#include <MESA/MESA_handle_logger.h>
 #include "tsg_protocol_common.h"
 
 #define MTU_LEN 65535
@@ -32,15 +33,23 @@
 #define IPV6_IP_PAYLOAD_INDEX  4         //ipv6_payload_index(4)
 
 
-int tamper_calc(char *str, int startlen, int endlen)
+int tamper_calc(const struct streaminfo *a_stream, char *str, int endlen)
 {
     int i = 0;
     int j = 0;
     char temp;
+    int startlen = 0;
+    int data_len = a_stream->ptcpdetail->datalen;   //tcp和udp结构体内容一样，取tcp的datalen即可
+
+
+    //判断是否需要偏移一个字节
+    if(data_len%2!=0){
+         startlen = 1;     
+    }
 
     //最小交换paythod的第2个字节和第四个字节，否则不处理
     if ((endlen - startlen) < 4){
-        return -1;
+        return 0;
     }
 
     //start_len+1 : 因为计算校验和是16bit为单位，这里调换16bit的低8bit。
@@ -50,37 +59,43 @@ int tamper_calc(char *str, int startlen, int endlen)
                 temp = str[i];
                 str[i] = str[j];
                 str[j] = temp;
-                return 0;
+                return i;
             }
         }
     }
-    return -1;
+    return 0;
 }
 
 unsigned char send_tamper_xxx(const struct streaminfo *a_stream, const void *raw_pkt)
 {
-    const char *p_trans_payload = (char *)a_stream->ptcpdetail->pdata;
+    const char *p_trans_payload = NULL;
-    int trans_layload_len = a_stream->ptcpdetail->datalen;
+    int trans_layload_len = 0;
     char tamper_buf[MTU_LEN] = {0}; 
-    unsigned char raw_route_dir = 0;
     int  ret = 0;
     
-    if(a_stream == NULL){
+    if(a_stream==NULL){
-        return STATE_DROPPKT;   
+        return STATE_GIVEME;   
     }
 
-    if((p_trans_payload==NULL)||(trans_layload_len<=0)||(a_stream->curdir==DIR_S2C)){
+    p_trans_payload = (char *)a_stream->ptcpdetail->pdata;
-        return STATE_DROPPKT;   
+    trans_layload_len = a_stream->ptcpdetail->datalen;
+    if((p_trans_payload==NULL)||(trans_layload_len<=0)){
+        return STATE_GIVEME;   
     }
 
     memcpy(tamper_buf, p_trans_payload, trans_layload_len);
-    ret = tamper_calc(tamper_buf, 0, trans_layload_len);
+    ret = tamper_calc(a_stream, tamper_buf, trans_layload_len);
-    if(ret < 0){
+    MESA_handle_runtime_log(g_tsg_para.logger,
-        return STATE_DROPPKT; 
+            RLOG_LV_DEBUG,
+            __FUNCTION__,
+            "Modify the index position of the payload: %d",
+            ret);
+    if(ret > 0){
+        ret=tsg_send_inject_packet(a_stream, SIO_DEFAULT, tamper_buf, trans_layload_len, a_stream->routedir); 
+        if(ret == 0){
+            return STATE_DROPPKT;
+        }
     }
 
-    raw_route_dir = (a_stream->curdir==DIR_C2S) ? a_stream->routedir : MESA_dir_reverse(a_stream->routedir);
+    return STATE_GIVEME;   
-    tsg_send_inject_packet(a_stream, SIO_DEFAULT, tamper_buf, trans_layload_len, raw_route_dir); 
-
-    return STATE_DROPPKT;
 }