ftp客户端的创建

1.本段代码采用了 select I/O端口复用

2.含有三种功能：ls,  上传文件， 下载文件。这是拷贝别人的代码，自己添加了注释，随后会进行修改，

　　自己需要的功能：上传文件， 下载文件，  （并且在传输途中，对所有的文件进行openssl加密）

 #include <stdio.h>
 #include <stdlib.h>
 #include <netdb.h>
 #include <errno.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <unistd.h>
 #include <string.h>
 #include <sys/ioctl.h>
 #include <sys/fcntl.h>

 #define MAXBUF             1024        //宏大小
 #define STDIN_FILENO     1            //标准输入
 #define STDOUT_FILENO     0            //标准输出

 #define USERNAME     220            //用户名
 #define PASSWORD      331            //密码
 #define LOGIN           230            //登录
 #define PATHNAME      257            //路径名
 #define CLOSEDATA     226            //
 #define ACTIONOK      250            //

 char *rbuf,*rbuf1,*wbuf,*wbuf1;

 char filename[];                    //文件名
 char *host;                            //要连接的服务器地址

 struct sockaddr_in servaddr;        //服务器的地址、端口结构体

 //1.第一步，打开一个TCP链接
 int cliopen(char *host,int port);
 //
 int strtosrv(char *str);
 int ftp_get(int sck,char *pDownloadFileName);
 int ftp_put(int sck,char *pUploadFileName_s);
 void cmd_tcp(int sockfd);                        //

 //主函数
 int main(int argc,char *argv[])
 {
     int fd;

     //判断输入参数
     if( != argc -)
     {
         printf("%s\n","missing <hostname>");
         exit();
     }

     //指定服务器地址
     host = argv[];
     //指定端口
     int port = ;

     rbuf = (char *)malloc(MAXBUF*sizeof(char));
     rbuf1 = (char *)malloc(MAXBUF*sizeof(char));
     wbuf = (char *)malloc(MAXBUF*sizeof(char));
     wbuf1 = (char *)malloc(MAXBUF*sizeof(char));

     //1.得到已连接的套接字
     fd = cliopen(host,port);

     //2.
     cmd_tcp(fd);

     exit();
 }

 //1.第一步，打开一个TCP链接
 int cliopen(char *host,int port)
 {
     int control_sock;

     //1.FTP 自己的传输地址结构体
     struct hostent *ht = NULL;

     //2.创建套接字
     control_sock = socket(AF_INET,SOCK_STREAM,);
     if(control_sock < )
     {
        printf("socket error\n");
        return -;
     }

     //3.将IP地址进行转换，变为FTP地址结构体
     ht = gethostbyname(host);
     if(!ht)
     {
         return -;
     }

    //4.连接服务器，返回套接字
     memset(&servaddr,,sizeof(struct sockaddr_in));
     memcpy(&servaddr.sin_addr.s_addr,ht->h_addr,ht->h_length);
     servaddr.sin_family = AF_INET;
     servaddr.sin_port = htons(port);

     if(connect(control_sock,(struct sockaddr*)&servaddr,sizeof(struct sockaddr)) == -)
     {
         return -;
     }
     return control_sock;
 }

 //匹配下载的文件名
 int s(char *str,char *s2)
 {
     //char s1[100];

     return sscanf(str," get %s",s2) == ;

 }

 //匹配上传的文件名
 int st(char *str,char *s1)
 {
     return sscanf(str," put %s",s1) == ;
 }

 //获取服务器 发送给 客户端的 IP地址 和 端口;
 int strtosrv(char *str)
 {
    int addr[];
    //printf("%s\n",str);
    sscanf(str,"%*[^(](%d,%d,%d,%d,%d,%d)",&addr[],&addr[],&addr[],&addr[],&addr[],&addr[]);
    bzero(host,strlen(host));
    sprintf(host,"%d.%d.%d.%d",addr[],addr[],addr[],addr[]);
    int port = addr[]* + addr[];
    return port;
 }

 //显示文件列表
 void ftp_list(int sockfd)
 {
     int nread;
     for(;;)
     {
         if((nread = recv(sockfd,rbuf1,MAXBUF,)) < )
         {
             printf("recv error\n");
         }
         else if(nread == )
         {
             //printf("over\n");
             break;
         }
         if(write(STDOUT_FILENO,rbuf1,nread) != nread)
             printf("send error to stdout\n");
         /*else
             printf("read something\n");*/
     }
     if(close(sockfd) < )
         printf("close error\n");
 }

 //下载文件
 int ftp_get(int sck,char *pDownloadFileName)
 {
    int handle = open(pDownloadFileName,O_WRONLY | O_CREAT | O_TRUNC, S_IREAD| S_IWRITE);
    int nread;
    printf("%d\n",handle);
    /*if(handle == -1)
        return -1;*/

     //2. 猜测 ====================应该是将 ssl 接口放在这里，用来传输数据

    for(;;)
    {
        if((nread = recv(sck,rbuf1,MAXBUF,)) < )
        {
           printf("receive error\n");
        }
        else if(nread == )
        {
           printf("over\n");
           break;
        }
     //   printf("%s\n",rbuf1);
        if(write(handle,rbuf1,nread) != nread)
            printf("receive error from server!");
        if(write(STDOUT_FILENO,rbuf1,nread) != nread)
            printf("receive error from server!");
    }
        if(close(sck) < )
            printf("close error\n");
 }

 //上传文件
 int ftp_put(int sck,char *pUploadFileName_s)
 {
    //int c_sock;
    int handle = open(pUploadFileName_s,O_RDWR);
    int nread;
    if(handle == -)
        return -;
    //ftp_type(c_sock,"I");

    //3. 猜测 ====================应该是将 ssl 接口放在这里，用来传输数据
    for(;;)
    {
        if((nread = read(handle,rbuf1,MAXBUF)) < )
        {
             printf("read error!");
        }
        else if(nread == )
           break;
        if(write(STDOUT_FILENO,rbuf1,nread) != nread)
             printf("send error!");
        if(write(sck,rbuf1,nread) != nread)
             printf("send error!");
    }
    if(close(sck) < )
         printf("close error\n");
 }

 //各种参数的执行
 void cmd_tcp(int sockfd)
 {
     int maxfdp1,nread,nwrite,fd,replycode,tag=,data_sock;
     int port;
     char *pathname;
     fd_set rset;                //可读文件描述符集合
     FD_ZERO(&rset);                //清空可读文件描述符集合
     maxfdp1 = sockfd + ;        //最大套接字

     for(;;)
     {
         //1.将  标准输入加入 可读文件描述符集合
          FD_SET(STDIN_FILENO,&rset);
         //2.将  命令套接字   加入可读文件描述符集合
          FD_SET(sockfd,&rset);

         //3.监听读事件
          if(select(maxfdp1,&rset,NULL,NULL,NULL)<)
          {
              printf("select error\n");
          }
          //4.判断标准输入是否有读事件
          if(FD_ISSET(STDIN_FILENO,&rset))
          {
              //5.清空读缓冲区 和 写缓冲区
               bzero(wbuf,MAXBUF);          //zero
               bzero(rbuf1,MAXBUF);

               if((nread = read(STDIN_FILENO,rbuf1,MAXBUF)) <)
                    printf("read error from stdin\n");
               nwrite = nread + ;

             //=======这里不懂，replycode  什么时候赋的值

             //6.命令套接字中  写入  用户名
               if(replycode == USERNAME)
               {
                   sprintf(wbuf,"USER %s",rbuf1);

                  if(write(sockfd,wbuf,nwrite) != nwrite)
                  {
                      printf("write error\n");
                  }
                  //printf("%s\n",wbuf);
                  //memset(rbuf1,0,sizeof(rbuf1));
                  //memset(wbuf,0,sizeof(wbuf));
                  //printf("1:%s\n",wbuf);
               }

             //7.命令套接字中  写入  密码
               if(replycode == PASSWORD)
               {
                    //printf("%s\n",rbuf1);
                    sprintf(wbuf,"PASS %s",rbuf1);
                    if(write(sockfd,wbuf,nwrite) != nwrite)
                       printf("write error\n");
                    //bzero(rbuf,sizeof(rbuf));
                    //printf("%s\n",wbuf);
                    //printf("2:%s\n",wbuf);
               }

               if(replycode ==  || replycode == LOGIN || replycode == CLOSEDATA || replycode == PATHNAME || replycode == ACTIONOK)
               {
               if(strncmp(rbuf1,"pwd",) == )
               {
                      //printf("%s\n",rbuf1);
                      sprintf(wbuf,"%s","PWD\n");
                      write(sockfd,wbuf,);
                      continue;
                  }
                  if(strncmp(rbuf1,"quit",) == )
                  {
                      sprintf(wbuf,"%s","QUIT\n");
                      write(sockfd,wbuf,);
                      //close(sockfd);
                     if(close(sockfd) <)
                        printf("close error\n");
                     break;
                  }
                  if(strncmp(rbuf1,"cwd",) == )
                  {
                      //sprintf(wbuf,"%s","PASV\n");
                      sprintf(wbuf,"%s",rbuf1);
                      write(sockfd,wbuf,nread);

                      //sprintf(wbuf1,"%s","CWD\n");

                      continue;
                  }

                  if(strncmp(rbuf1,"ls",) == )
                  {
                      tag = ;            //显示文件 标识符
                      //printf("%s\n",rbuf1);
                      sprintf(wbuf,"%s","PASV\n");
                      //printf("%s\n",wbuf);
                      write(sockfd,wbuf,);
                      //read
                      //sprintf(wbuf1,"%s","LIST -al\n");
                      nwrite = ;
                      //write(sockfd,wbuf1,nwrite);
                      //ftp_list(sockfd);
                      continue;
                  }
                  //8.下载文件
                  if(strncmp(rbuf1,"get",) == )
                  {
                      tag = ;            //下载文件标识符

                      //被动传输模式
                      sprintf(wbuf,"%s","PASV\n");
                      //printf("%s\n",s(rbuf1));
                      //char filename[100];
                      s(rbuf1,filename);
                      printf("%s\n",filename);
                      write(sockfd,wbuf,);
                      continue;
                  }

                  if(strncmp(rbuf1,"put",) == )
                  {
                      tag = ;            //上传文件标识符
                      sprintf(wbuf,"%s","PASV\n");

                     //把内容赋值给  读缓冲区
                      st(rbuf1,filename);
                      printf("%s\n",filename);
                      write(sockfd,wbuf,);
                      continue;
                  }
               }
                     /*if(close(sockfd) <0)
                        printf("close error\n");*/
          }
          if(FD_ISSET(sockfd,&rset))
          {
          //9.清空读缓冲区 和 写缓冲区
              bzero(rbuf,strlen(rbuf));
          //10.读套接字中的内容
              if((nread = recv(sockfd,rbuf,MAXBUF,)) <)
                   printf("recv error\n");
              else if(nread == )
                break;

            //比较
              if(strncmp(rbuf,"",) == || strncmp(rbuf,"",)==)
              {
                 /*if(write(STDOUT_FILENO,rbuf,nread) != nread)
                     printf("write error to stdout\n");*/

                  //链接字符串
                  strcat(rbuf,"your name:");

                  //printf("%s\n",rbuf);
                  nread += ;
                 /*if(write(STDOUT_FILENO,rbuf,nread) != nread)
                     printf("write error to stdout\n");*/
                  replycode = USERNAME;
              }
              if(strncmp(rbuf,"",) == )
              {
                 /*if(write(STDOUT_FILENO,rbuf,nread) != nread)
                     printf("write error to stdout\n")*/;
                 strcat(rbuf,"your password:");
                 nread += ;
                 /*if(write(STDOUT_FILENO,rbuf,nread) != nread)
                     printf("write error to stdout\n");*/
                 replycode = PASSWORD;
              }
              if(strncmp(rbuf,"",) == )
              {
                 /*if(write(STDOUT_FILENO,rbuf,nread) != nread)
                     printf("write error to stdout\n");*/
                 replycode = LOGIN;
              }
              if(strncmp(rbuf,"",) == )
              {
                 /*if(write(STDOUT_FILENO,rbuf,nread) != nread)
                     printf("write error to stdout\n");*/
                 replycode = PATHNAME;
              }
              if(strncmp(rbuf,"",) == )
              {
                 /*if(write(STDOUT_FILENO,rbuf,nread) != nread)
                     printf("write error to stdout\n");*/
                 replycode = CLOSEDATA;
              }
              if(strncmp(rbuf,"",) == )
              {
                 /*if(write(STDOUT_FILENO,rbuf,nread) != nread)
                     printf("write error to stdout\n");*/
                 replycode = ACTIONOK;
              }
              if(strncmp(rbuf,"",) == )
              {
                 replycode = ;
              }
              /*if(strncmp(rbuf,"150",3) == 0)
              {
                 if(write(STDOUT_FILENO,rbuf,nread) != nread)
                     printf("write error to stdout\n");
              }*/
              //fprintf(stderr,"%d\n",1);
              if(strncmp(rbuf,"",) == )
              {
                 //printf("%d\n",1);
                 /*if(write(STDOUT_FILENO,rbuf,nread) != nread)
                    printf("write error to stdout\n");*/

                 //获取服务器返回的 接收数据的端口，和地址
                 int port1 = strtosrv(rbuf);
                 printf("%d\n",port1);
                 printf("%s\n",host);

                 //创建新的传输数据的套接字?
                 //1. 猜测 ====================应该是将 ssl 接口放在这里，用来传输数据
                 data_sock = cliopen(host,port1);

 //bzero(rbuf,sizeof(rbuf));
                 //printf("%d\n",fd);
                 //if(strncmp(rbuf1,"ls",2) == 0)
                 if(tag == )
                 {
                    write(sockfd,"list\n",strlen("list\n"));
                    ftp_list(data_sock);
                    /*if(write(STDOUT_FILENO,rbuf,nread) != nread)
                        printf("write error to stdout\n");*/

                 }
                 //else if(strncmp(rbuf1,"get",3) == 0)
                 else if(tag == )
                 {
                     //sprintf(wbuf,"%s","RETR\n");
                     //printf("%s\n",wbuf);
                     //int str = strlen(filename);
                     //printf("%d\n",str);
                     sprintf(wbuf,"RETR %s\n",filename);
                     printf("%s\n",wbuf);
                     //int p = 5 + str + 1;

                     //命令套接字中写入  下载文件命令
                     printf("%d\n",write(sockfd,wbuf,strlen(wbuf)));
                     //printf("%d\n",p);

                     //下载文件
                     ftp_get(data_sock,filename);
                 }
                 else if(tag == )
                 {

                     // 上传文件
                     sprintf(wbuf,"STOR %s\n",filename);
                     printf("%s\n",wbuf);
                     write(sockfd,wbuf,strlen(wbuf));
                     ftp_put(data_sock,filename);
                 }
                 nwrite = ;
              }
              /*if(strncmp(rbuf,"150",3) == 0)
              {
                  if(write(STDOUT_FILENO,rbuf,nread) != nread)
                      printf("write error to stdout\n");
              }*/
              //printf("%s\n",rbuf);
              if(write(STDOUT_FILENO,rbuf,nread) != nread)
                  printf("write error to stdout\n");
              /*else
                  printf("%d\n",-1);*/
          }
     }
 }