vde/vdetaplib/vdetap.c

   1 /* Copyright 2004 Renzo Davoli
   2  * Reseased under the GPLv2 */
   3
   4 #include <config.h>
   5 #include <stdio.h>
   6 #include <stdint.h>
   7 #include <sys/select.h>
   8 #include <sys/poll.h>
   9 #include <sys/socket.h>
  10 #include <sys/un.h>
  11
  12 #define SWITCH_MAGIC 0xfeedface
  13 #define BUFSIZE 2048
  14
  15 enum request_type { REQ_NEW_CONTROL };
  16 struct request_v3 {
  17         uint32_t magic;
  18         uint32_t version;
  19         enum request_type type;
  20         struct sockaddr_un sock;
  21 };
  22
  23 static unsigned char bufin[BUFSIZE];
  24
  25 static int send_fd(char *name, int fddata, struct sockaddr_un *datasock, int intno, int group)
  26 {
  27         int pid = getpid();
  28         struct request_v3 req;
  29         int fdctl;
  30
  31         struct sockaddr_un sock;
  32
  33         if((fdctl = socket(AF_UNIX, SOCK_STREAM, 0)) < 0){
  34                 perror("socket");
  35                 exit(1);
  36         }
  37
  38         sock.sun_family = AF_UNIX;
  39         snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name);
  40         if(connect(fdctl, (struct sockaddr *) &sock, sizeof(sock))){
  41                 perror("connect");
  42                 exit(1);
  43         }
  44
  45         req.magic=SWITCH_MAGIC;
  46         req.version=3;
  47         req.type=REQ_NEW_CONTROL+((group > 0)?((geteuid()<<8) + group) << 8:0);
  48
  49         req.sock.sun_family=AF_UNIX;
  50         memset(req.sock.sun_path, 0, sizeof(req.sock.sun_path));
  51         sprintf(&req.sock.sun_path[1], "%5d-%2d", pid, intno);
  52
  53         if(bind(fddata, (struct sockaddr *) &req.sock, sizeof(req.sock)) < 0){
  54                 perror("bind");
  55                 exit(1);
  56         }
  57
  58         if (send(fdctl,&req,sizeof(req),0) < 0) {
  59                 perror("send");
  60                 exit(1);
  61         }
  62
  63         if (recv(fdctl,datasock,sizeof(struct sockaddr_un),0)<0) {
  64                 perror("recv");
  65                 exit(1);
  66         }
  67
  68         return fdctl;
  69 }
  70
  71 static struct pollfd pollv[]={{0,POLLIN|POLLHUP,0},{0,POLLIN|POLLHUP,0}};
  72
  73 main(int argc,char *argv[])
  74 {
  75         int fd,fddata;
  76         struct sockaddr_un dataout,datain;
  77         int datainsize,result,nx;
  78         register int i;
  79         /*printf("argc = %d\n",argc);
  80         for (i=0;i<argc;i++)
  81                 printf("argv %d -%s-\n",i,argv[i]);*/
  82         if (argc != 3 && argv[0][0] != '-') {
  83                 fprintf(stderr,"vdetap must be activated by libvdetap e.g.\n"
  84                                 "   sh%% export LD_PRELOAD=/usr/local/lib/libvdetap.so\n"
  85                                 "   csh%% setenv LD_PRELOAD /usr/local/lib/libvdetap.so\n");
  86                 exit (-1);
  87         }
  88
  89         fd = atoi(argv[1]);
  90         for (i=3;i<FD_SETSIZE;i++)
  91                 if (i != fd)
  92                         close(i);
  93         if((fddata = socket(AF_UNIX, SOCK_DGRAM, 0)) < 0){
  94                 perror("socket");
  95                 exit(1);
  96         }
  97         send_fd(argv[2],fddata,&dataout,0,0);
  98         pollv[0].fd=fd;
  99         pollv[1].fd=fddata;
 100         for(;;) {
 101                 result=poll(pollv,2,-1);
 102                 if (pollv[0].revents & POLLHUP || pollv[1].revents & POLLHUP)
 103                         break;
 104                 if (pollv[0].revents & POLLIN) {
 105                         nx=read(fd,bufin,sizeof(bufin));
 106                         /*fprintf(stderr,"RX from pgm %d\n",nx);*/
 107                         //send(connected_fd,bufin,nx,0);
 108                         sendto(fddata,bufin,nx,0,(struct sockaddr *) &dataout, sizeof(struct sockaddr_un));
 109                 }
 110                 if (pollv[1].revents & POLLIN) {
 111                         datainsize=sizeof(datain);
 112                         nx=recvfrom(fddata,bufin,BUFSIZE,0,(struct sockaddr *) &datain, &datainsize);
 113                         /*fprintf(stderr,"TX to pgm %d\n",nx);*/
 114                         write(fd,bufin,nx);
 115                 }
 116         }
 117 }
 118