Diff: Codes/TelnetServer.cpp

Revision:

0:e57bc370d339

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Codes/TelnetServer.cpp	Tue Jan 05 11:45:44 2016 +0000
@@ -0,0 +1,216 @@
+/*
+    Original autor: Francisco
+    Modificacao do uso da rede: rebonatto
+*/
+
+
+#include "TelnetServer.h"
+
+#include "Split.h"
+
+#define OPT_WILL    251
+#define OPT_WONT    252
+#define OPT_DO      253
+#define OPT_DONT    254
+
+char* welcome_msg = "Protegemed - welcome to telnet\r\nType 'help' for a list of commands\r\n";
+char *command_not_found_msg_get = "Command not found.\r\n\r\n";
+char* prompt_msg = "\r\n$ ";
+char iac_will_echo[] = {0xFF,0xFB,0x01};
+char erase_cmd[] = { 0x1B,0x5B,0x44,0x1B,0x5B,0x4B}; 
+
+const struct telnet_cmd_handler TelnetServer::cmds[] = {
+        {"exit",(cmd_function)-1},
+        {"help",TelnetServer::HelpCommand},
+        {"reset",TelnetServer::ResetCommand},
+        {"remove",TelnetServer::RemoveCommand},
+        {"listparam",TelnetServer::ListParamCommand},
+        {"getparam",TelnetServer::GetParamCommand},
+        {"setparam",TelnetServer::SetParamCommand},
+        {"version",TelnetServer::VersionCommand},
+        {"update",TelnetServer::UpdateCommand},
+        {"",(cmd_function)0}
+};
+
+void TelnetServer::TelnetServer_Thread(void const* arg)
+{
+    int r=0;
+    printf("Telnet Thread starting... \r\nCommands up to 100 chars\n");
+    
+    TCPSocketServer server;                     
+    
+    server.bind(23);
+    server.listen();
+    
+    while(1)
+    {
+        TCPSocketConnection* conn ;
+        TCPSocketConnection aux;
+        r = server.accept(aux);
+        conn = &aux;
+        printf("Aceitou conexao \n");
+        if (r != 0){
+            printf("Error in connection\n");
+            exit(1);
+        }            
+        
+        TelnetSession(conn);
+        printf("Fechou\n");
+        conn->close();
+    }
+}
+
+void TelnetServer::TelnetSession(TCPSocketConnection *conn)
+{
+    int r, flag;
+    int buffer_ptr=0;   
+
+    printf("Connected to %s:%d\n",conn->get_address(),conn->get_port());            
+    
+    conn->send(welcome_msg,strlen(welcome_msg));
+    conn->send(prompt_msg,strlen(prompt_msg));
+    
+    conn->set_blocking(true);
+    
+    while(1)
+    {                         
+        char buf_rec[260];
+        unsigned char buf[260];
+        char buffer[260];
+        
+        //printf("Vai recevber\n");
+        r = conn->receive(buf_rec, strlen(buf_rec) );        
+        
+        /* need memcpy becouse commands are ready to unsigned char and tcp receive char */
+        memcpy(buf, buf_rec, r);        
+        
+        //printf("Receive %d\n", r);
+        
+        if(r == -1)
+        {
+            printf("Error %d %s\n", r, buf);
+            break;
+        }
+        
+        if (r > 120){
+            printf("Max command length = 100 chars\n");
+            //send
+            break;        
+        }                
+                
+        //printf("Got Here %d *%s*\n", r, buf);        
+        //printf("\n\nGot Here2 [%s]\n\n", buf_rec);
+        
+        for(int i=0;i<r;i++)
+        {
+            //check if it is a printable or any of the line control chars
+            if((buf[i]>31 && buf[i] < 128) || buf[i]=='\r' || buf[i]=='\n' || buf[i]=='\t')
+            {
+                //append to the buffer                
+                buffer[buffer_ptr] = buf[i];
+                buffer_ptr++;
+            }
+            else if(buf[i] == '\b')  //backspace
+            {
+                //erases the character from the command buffer
+                if(buffer_ptr > 0)
+                {
+                    buffer_ptr--;
+                }
+                //resets m variable state (will not cause error on the next block of code
+                
+            }
+            else if((int)buf[i] == 255)   //IAC - Interpret As Command
+            {
+                if((int)buf[i+1] >= 251)
+                {
+                    option_negotiator(conn,buf[i+1],buf[i+2]);
+                    i+=2;
+                }
+                else
+                    i+=1;
+            }
+        }                
+        
+        //detect a carriage return and line feed sequence. Trigger command processor
+        if(buffer_ptr >= 2)
+        {
+            if(buffer[buffer_ptr-1] == '\n' && buffer[buffer_ptr-2] == '\r')
+            {
+                char **command;
+                int command_count;
+
+                buffer[buffer_ptr-2] = '\0';
+                command_count = split((char*)buffer," ",&command);
+                
+                printf("Command found: %s\n", command[0]);
+                flag = 1;
+                //must find a function in the table and then execute it, passing the command array as an argument
+                for(int i=0;cmds[i].pfn != 0;i++)
+                {
+                    if(!strcasecmp(command[0],cmds[i].command_name))
+                    {
+                        if((int)cmds[i].pfn == -1)//exit cmd
+                        {
+                            //delete buffer;                            
+                            return;
+                        }
+                        else
+                        {
+                            flag = 0;
+                            cmds[i].pfn(conn,command,command_count);
+                            break;
+                        }
+                    }
+                }
+
+                if (flag)
+                    conn->send(command_not_found_msg_get,strlen(command_not_found_msg_get));        
+                                    
+                //write the prompt
+                conn->send(prompt_msg,strlen(prompt_msg));
+                buffer_ptr=0;
+            }
+        }
+        //buf_rec[0] = buf[0] = buffer[0] = '\0';    
+    }
+    
+    //delete buffer;
+    
+    
+}
+
+void TelnetServer::option_negotiator(TCPSocketConnection *conn,unsigned char opt_cmd,unsigned char opt_param)
+{
+    char opt[3]={0,0,0};    
+
+    if(opt_param == 1 && (opt_cmd == OPT_DO || opt_cmd == OPT_DONT))    //response for our will echo
+    {
+        printf("HERE");
+        return;
+    }
+    if(opt_cmd == OPT_DO)   //every other option that it will ask to us to do, we won't
+    {
+        opt[0] = 255;
+        opt[1] = OPT_WONT;
+        opt[2] = opt_param;
+        conn->send(opt,3);
+    }
+    else if(opt_cmd == OPT_WILL && opt_param==3)    //OK to supperss go ahead
+    {
+        opt[0] = 255;
+        opt[1] = OPT_DO;
+        opt[2] = opt_param;
+        conn->send(opt,3);
+    }
+    else if(opt_cmd == OPT_WILL)    //every other option that it will ask do, we don't
+    {
+        opt[0] = 255;
+        opt[1] = OPT_DONT;
+        opt[2] = opt_param;
+        conn->send(opt,3);
+        
+    }
+
+}
+