ftpclient.c

linux下编程实现的基本FTP

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <strings.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include "ftp.h"

#define SERVER_CTRL_PORT	21
#define MAX_INFO 1024
#define CMD_BUF_LEN 100

int  ftp_Control_sock;
char server_Control_Info[MAX_INFO];
char server_Data_Info[MAX_INFO];
char user_cmd_info[CMD_BUF_LEN];
char format_cmd_info[CMD_BUF_LEN];
char file_name_info[CMD_BUF_LEN];


void get_Server_Control_Info(char* cmd,int length)
{
	int len;
	if(length!=0)
   	{
   	len = write(ftp_Control_sock, cmd, length);
		printf("%d bytes writen %s\n", len,cmd);
	}
	
	memset(server_Control_Info, 0, MAX_INFO);	
	int bytes;
	if((bytes=recv(ftp_Control_sock,server_Control_Info,MAX_INFO,0))==-1)
	{
		printf("recv error\n");
		exit(-1);
	}
	server_Control_Info[bytes]='\0';
	printf("Server Message:\n%s\n",server_Control_Info);
}
struct sockaddr_in get_Server_Data_Port()
{	
    struct sockaddr_in dataSock;
	 char *sc;
	 char ip[16];
	 char cport[4];
	 int port;
	 int flag=0; 
	 int ipnum=0;
	 int ipt=0;
	 int portnum=0;
	 int portt=0;
	 for (sc =server_Control_Info; *sc != '\0'; ++sc)
	  {
	  	if(flag==2)
	  	{
	  		if(*sc==','||*sc==')')
	  		{
	  			cport[portnum]='\0';
	  			port=port*portt+atoi(cport);
	  			portt=256;
	  			portnum=0;
	  		}
	  		else if(*sc!=',')
	  		{
	  			cport[portnum]=*sc;
	  			portnum++;
	  		}
	  	}
	  	if(flag==1)
	  	{
	  		if(*sc!=',')
	  		{
	  			ip[ipnum]=*sc;
	  		}
	  		else 
	  		{
	  			ipt++;
	  			if(ipt<4)ip[ipnum]='.';	
	  			else 
	  			{
	  				flag=2;
	  				ip[ipnum]='\0';
	  			}
	  		}
	  		ipnum++;
	  	}
	  	if(*sc=='(')flag=1;
	  	if(*sc==')')break;
	  }
    bzero(&dataSock, sizeof(dataSock));
	 dataSock.sin_family = AF_INET;
	 dataSock.sin_port = htons(port);
	 if(inet_pton(AF_INET,ip, &dataSock.sin_addr)<=0)
	  {
		printf("IP address invalid!\n");
		exit(-1);
	 }
	 return dataSock;
}
void get_Server_Data_Info(char* cmd,int length)
{
	char pasv_cmd[7]="pasv\r\n"; 
	get_Server_Control_Info(pasv_cmd,strlen(pasv_cmd));
   struct sockaddr_in data_Temp_addr=get_Server_Data_Port();
   int ftp_data_sock;
   if ((ftp_data_sock=socket(AF_INET,SOCK_STREAM,0))==-1)
	{
		fprintf(stderr,"Socket Create Error:%s\a\n",strerror(errno));
		exit(1);
	}
   if(connect(ftp_data_sock, (struct sockaddr*)(&data_Temp_addr), sizeof(struct sockaddr_in)) < 0)
    	{
		printf("connection failed!\n");
		exit(-1);
    	}
   if (strncmp("dir", cmd, 3) == 0)
    	{
    	   char list_cmd[7]="list\r\n"; 
    	   get_Server_Control_Info(list_cmd,strlen(list_cmd));
    		int cmd_sock=fileno(stdout);
    		int n; 
    		memset(server_Data_Info, 0, MAX_INFO);	
    		while ((n = read(ftp_data_sock, server_Data_Info, MAX_INFO)) > 0)
			{
	    			if (write(cmd_sock, server_Data_Info, n) != n)
	    				{
						printf("read from server error in get_server_data\n");
						return;
	  				 }
			}	
			close(ftp_data_sock);			
			get_Server_Control_Info(list_cmd,0);
    	}
    	/////////////////////////////////////////
   if (strncmp("retr", cmd, 4) == 0)
    	{
    		char type_cmd[9]="TYPE I\r\n";
    	   get_Server_Control_Info(type_cmd,strlen(type_cmd));
    	   
    	   get_Server_Control_Info(cmd,strlen(cmd));
    	   
    	   FILE* fp = fopen(file_name_info, "ab");
	    	if (fp == NULL)
	    		{
					printf("open file %s error\n",file_name_info);
					return;
	    		}
    		int cmd_sock=fileno(fp);
    		int n; 
    		memset(server_Data_Info, 0, MAX_INFO);	
    		while ((n = read(ftp_data_sock, server_Data_Info, MAX_INFO)) > 0)
			{
	    			if (write(cmd_sock, server_Data_Info, n) != n)
	    				{
						printf("read from server error in get_server_data\n");
						return;
	  				 }
			}
			fclose(fp);
			close(ftp_data_sock);
			get_Server_Control_Info(cmd,0);
			char transter[]="226 ";
			while(strstr(server_Control_Info,transter)==NULL)
				get_Server_Control_Info(cmd,0);
    	}
   if (strncmp("stor", cmd, 4) == 0)
    	{
    	   char type_cmd[9]="TYPE I\r\n";
    	   get_Server_Control_Info(type_cmd,strlen(type_cmd));
    	   FILE* fp = fopen(file_name_info, "rb");
	    	if (fp == NULL)
	    		{
					printf("open file %s error\r\n",file_name_info);
					close(ftp_data_sock);
					return;
	    		}
	    	get_Server_Control_Info(cmd,strlen(cmd));
    		int cmd_sock=fileno(fp);
    		int n; 
    		memset(server_Data_Info, 0, MAX_INFO);	
    		while ((n = read(cmd_sock, server_Data_Info, MAX_INFO)) > 0)
			{
	    			if (write(ftp_data_sock, server_Data_Info, n) != n)
	    				{
						printf("read from server error in get_server_data\n");
						return;
	  				 }
			}
			fclose(fp);
			close(ftp_data_sock);
			get_Server_Control_Info(cmd,0);
			char transter[]="226 ";
			while(strstr(server_Control_Info,transter)==NULL)
				get_Server_Control_Info(cmd,0);
    	}
  // close(ftp_data_sock);
}

int main(int argc,char *argv[])
{
	struct sockaddr_in servaddr,localaddr;
	
/*************************************************************/
/*	      				 建立tcp连接 				      */
/*************************************************************/		
 	if(argc != 4)
    	{
		printf("Useage: %s <IP address> user password\n",argv[0]);
		exit(-1);
    	}
	
	if ((ftp_Control_sock=socket(AF_INET,SOCK_STREAM,0))==-1)
	{
		fprintf(stderr,"Socket Create Error:%s\a\n",strerror(errno));
		exit(1);
	}
	bzero(&servaddr, sizeof(servaddr));
	servaddr.sin_family = AF_INET;
	servaddr.sin_port = htons(SERVER_CTRL_PORT);
	if(inet_pton(AF_INET,argv[1], &servaddr.sin_addr)<=0)
	{
		printf("IP address invalid!\n");
		exit(-1);
	}
	if(connect(ftp_Control_sock, (struct sockaddr*)(&servaddr), sizeof(struct sockaddr_in)) < 0)
        {
		printf("Connection failed!\n");
		exit(-1);
    	}
   printf("Connected to host %s successfully\n", argv[1]);
   	
   int bytes;
/*************************************************************/
/*	       接收ftp的welcome message			  */
/*************************************************************/	

	if((bytes=recv(ftp_Control_sock,server_Control_Info,MAX_INFO,0))==-1)
	{
		printf("recv error\n");
		exit(-1);
	}
	server_Control_Info[bytes]='\0';
	printf("Server Message:%s\n",server_Control_Info);
	
/*************************************************************/
/*	                        			登录 					*/
/*************************************************************/	
   //int lolen;
   char loginbuf[CMD_BUF_LEN];
   snprintf(loginbuf, CMD_BUF_LEN, "USER %s\r\n", argv[2]);
   get_Server_Control_Info(loginbuf,strlen(loginbuf));
   snprintf(loginbuf, CMD_BUF_LEN, "PASS %s\r\n", argv[3]);
   get_Server_Control_Info(loginbuf,strlen(loginbuf));
	
	while(1)
	{
/*************************************************************/
/*	                        接收命令输入 		 				*/
/*************************************************************/	
		printf("ftp>");
		memset(user_cmd_info, 0, CMD_BUF_LEN);
    	if (fgets(user_cmd_info, CMD_BUF_LEN, stdin) == NULL)		
   		{
			printf("user input error\n");
			return -1;
    		}	
    		
    	if (strncmp("pwd", user_cmd_info, 3) == 0)
    		{
    		   char pwd_cmd[6]="pwd\r\n"; 
    			get_Server_Control_Info(pwd_cmd,strlen(pwd_cmd));
    		}
    	if (strncmp("quit", user_cmd_info, 4) == 0)
    		{
    		   char quit_cmd[7]="quit\r\n"; 
    			get_Server_Control_Info(quit_cmd,strlen(quit_cmd));
    			exit(-1);
    		}
    	if (strncmp("?", user_cmd_info, 1) == 0)
    		{
    		   int i=0;
    		   for(i=0;i<COMMAND_NUM;i++)
    		   		{
    		   			printf("%s\n",clientCommand[i]);
    		   		}
    		}
    	if(strncmp("dir",user_cmd_info,3)  == 0)
    		{
    			char dir_cmd[6]="dir\r\n"; 
    			get_Server_Data_Info(dir_cmd,strlen(dir_cmd));
    		}
    	if(strncmp("cd",user_cmd_info,2)  == 0)
    		{
    			int ti=0; 
    		   int length=strlen(user_cmd_info); 
    			format_cmd_info[0]='c';
				format_cmd_info[1]='w';
				format_cmd_info[2]='d';
				format_cmd_info[3]=' ';
				for(ti=3;ti<length;ti++)
					format_cmd_info[ti+1]=user_cmd_info[ti];
				format_cmd_info[ti]='\r';
				format_cmd_info[ti+1]='\n';
				format_cmd_info[ti+2]='\0';		
    			get_Server_Control_Info(format_cmd_info,length+3);
    		}
    	if(strncmp("get",user_cmd_info,3)  == 0)
    		{
    			int ti=0; 
    		   int length=strlen(user_cmd_info); 
    			format_cmd_info[0]='r';
				format_cmd_info[1]='e';
				format_cmd_info[2]='t';
				format_cmd_info[3]='r';
				format_cmd_info[4]=' ';
				for(ti=4;ti<length;ti++)
				{
					format_cmd_info[ti+1]=user_cmd_info[ti];
					file_name_info[ti-4]=user_cmd_info[ti];
				}
				file_name_info[ti-5]='\0';
				format_cmd_info[ti]='\r';
				format_cmd_info[ti+1]='\n';
				format_cmd_info[ti+2]='\0';			
    			get_Server_Data_Info(format_cmd_info,length+3);
    		}
      if(strncmp("put",user_cmd_info,3)  == 0)
    		{
    			int ti=0; 
    		   int length=strlen(user_cmd_info);        
    			format_cmd_info[0]='s';
				format_cmd_info[1]='t';
				format_cmd_info[2]='o';
				format_cmd_info[3]='r';
				format_cmd_info[4]=' ';
				for(ti=4;ti<length;ti++)
				{
					format_cmd_info[ti+1]=user_cmd_info[ti];
					file_name_info[ti-4]=user_cmd_info[ti];
				}
				file_name_info[ti-5]='\0';
				format_cmd_info[ti]='\r';
				format_cmd_info[ti+1]='\n';
				format_cmd_info[ti+2]='\0';			
    			get_Server_Data_Info(format_cmd_info,length+3);
    		}
    			
	}
	close(ftp_Control_sock);
	
}