commands/rget/rget.c

   1 /*      rget 2.6 - remote pipe                          Author: Kees J. Bot
   2  *                                                              20 Mar 1989
   3  *
   4  * here$ ... | rput key                 there$ rget -h here key | ...
   5  * here$ rput key command ...           there$ rget -h here key command ...
   6  *
   7  * (Once my first try at network programming, completely reworked by now.)
   8  */
   9 #define nil ((void*)0)
  10 #include <sys/types.h>
  11 #include <sys/ioctl.h>
  12 #include <stdio.h>
  13 #include <fcntl.h>
  14 #include <stdlib.h>
  15 #include <unistd.h>
  16 #include <string.h>
  17 #include <errno.h>
  18 #if __minix
  19 #include <net/gen/in.h>
  20 #include <net/gen/inet.h>
  21 #include <net/gen/netdb.h>
  22 #include <net/gen/socket.h>
  23 #include <net/gen/tcp.h>
  24 #include <net/gen/tcp_hdr.h>
  25 #include <net/gen/tcp_io.h>
  26 #include <net/hton.h>
  27 #include <net/netlib.h>
  28 #else
  29 #include <sys/socket.h>
  30 #include <netinet/in.h>
  31 #include <netdb.h>
  32 #endif
  33
  34 static char *name;
  35 static int iflag, oflag, hflag, lflag, cflag;   /* -iolch? */
  36 static char *host;                              /* Argument to -h. */
  37 static struct hostent *hent;                    /* gethostbyname(host) */
  38 static char *key;                               /* key (port) */
  39 static char **cmdv;                             /* command [arg ...] */
  40
  41 static void fatal(const char *label)
  42 {
  43     int err= errno;
  44
  45     fprintf(stderr, "%s: %s: %s\n", name, label, strerror(err));
  46     exit(1);
  47 }
  48
  49 static unsigned name2port(char *n)
  50 {
  51     char *end;
  52     unsigned port;
  53
  54     port= strtoul(n, &end, 0);
  55     if (end == n || *end != 0) {
  56         port= 1;
  57         while (*n != 0) port *= (*n++ & 0xFF);
  58         port |= 0x8000;
  59     }
  60     return htons(port & 0xFFFF);
  61 }
  62
  63 static void usage(void)
  64 {
  65     fprintf(stderr,
  66         "Usage: %s [-lcio] [-h host] key [command [arg ...]]\n"
  67         "\t-l: Open TCP socket and listen (default for rput)\n"
  68         "\t-c: Connect to a remote TCP socket (default for rget)\n"
  69         "\t-i: Tie standard input to the TCP stream (default for rget)\n"
  70         "\t-o: Tie standard output to the TCP stream (default for rput)\n"
  71         "\t-io: Bidirectional!\n"
  72         "\tkey: A word to hash into a port number, or simply a port number\n",
  73         name);
  74     exit(1);
  75 }
  76
  77 int main(int argc, char **argv)
  78 {
  79     int i, s;
  80
  81     if ((name= strrchr(argv[0], '/')) == nil) name= argv[0]; else name++;
  82
  83     if (strcmp(name, "rget") != 0 && strcmp(name, "rput") != 0) {
  84         fprintf(stderr, "Don't know what to do if you call me '%s'\n", name);
  85         exit(1);
  86     }
  87
  88     i= 1;
  89     while (i < argc && argv[i][0] == '-') {
  90         char *opt= argv[i++]+1;
  91
  92         if (opt[0] == '-' && opt[1] == 0) break;        /* -- */
  93
  94         while (*opt != 0) switch (*opt++) {
  95         case 'l':       lflag= 1;       break;
  96         case 'c':       cflag= 1;       break;
  97         case 'i':       iflag= 1;       break;
  98         case 'o':       oflag= 1;       break;
  99         case 'h':
 100             hflag= 1;
 101             if (*opt == 0) {
 102                 if (i == argc) usage();
 103                 opt= argv[i++];
 104             }
 105             host= opt;
 106             opt= "";
 107             break;
 108         default:        usage();        break;
 109         }
 110     }
 111
 112     if (i == argc) usage();
 113     key= argv[i++];
 114     cmdv= argv + i;
 115
 116     /* Defaults. */
 117     if (!lflag && !cflag) {
 118         if (name[1] == 'p') lflag= 1;
 119         if (name[1] == 'g') cflag= 1;
 120     }
 121     if (!iflag && !oflag) {
 122         if (name[1] == 'g') iflag= 1;
 123         if (name[1] == 'p') oflag= 1;
 124     }
 125
 126     /* Constraints. */
 127     if (lflag && cflag) {
 128         fprintf(stderr, "%s: -c and -l don't mix\n", name);
 129         usage();
 130     }
 131     if (cflag && !hflag) {
 132         fprintf(stderr, "%s: -c requires a host name given with -h\n", name);
 133         usage();
 134     }
 135     if (lflag && hflag) {
 136         fprintf(stderr, "%s: -l does not require a host name given with -h\n",
 137             name);
 138         usage();
 139     }
 140     if (iflag && oflag && cmdv[0] == nil) {
 141         fprintf(stderr, "%s: -io requires that a command is given\n", name);
 142         usage();
 143     }
 144
 145     if (hflag) {
 146         if ((hent= gethostbyname(host)) == nil) {
 147             fprintf(stderr, "%s: %s: Name lookup failed\n", name, host);
 148             exit(1);
 149         }
 150     }
 151
 152     s= -1;
 153     if (lflag) {
 154         /* We need to listen and wait.  (We're "rput", most likely.) */
 155 #if __minix
 156         char *tcp_device;
 157         struct nwio_tcpconf tcpconf;
 158         struct nwio_tcpcl tcplistenopt;
 159
 160         if ((tcp_device= getenv("TCP_DEVICE")) == nil) tcp_device= "/dev/tcp";
 161         if ((s= open(tcp_device, O_RDWR)) < 0) fatal(tcp_device);
 162
 163         tcpconf.nwtc_flags=
 164             NWTC_EXCL | NWTC_LP_SET | NWTC_UNSET_RA | NWTC_UNSET_RP;
 165         tcpconf.nwtc_locport= name2port(key);
 166         if (ioctl(s, NWIOSTCPCONF, &tcpconf) < 0) fatal("NWIOSTCPCONF");
 167
 168         tcplistenopt.nwtcl_flags= 0;
 169         if (ioctl(s, NWIOTCPLISTEN, &tcplistenopt) < 0) fatal("NWIOTCPLISTEN");
 170 #else
 171         int sa;
 172         struct sockaddr_in channel;
 173         static int on= 1;
 174
 175         if ((s= socket(AF_INET, SOCK_STREAM, IPPROTO_TCP))<0) fatal("socket()");
 176
 177         (void) setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *) &on,
 178                                                                 sizeof(on));
 179         memset(&channel, 0, sizeof(channel));
 180         channel.sin_family= AF_INET;
 181         channel.sin_addr.s_addr= htonl(INADDR_ANY);
 182         channel.sin_port= name2port(key);
 183         if (bind(s, (struct sockaddr *) &channel, sizeof(channel)) < 0)
 184             fatal("bind()");
 185
 186         if (listen(s, 0) < 0) fatal("listen()");
 187
 188         if ((sa= accept(s, nil, nil)) < 0) fatal("accept()");
 189         close(s);
 190         s= sa;
 191 #endif
 192     }
 193
 194     if (cflag) {
 195         /* Connect to the remote end.  (We're "rget", most likely.) */
 196 #if __minix
 197         int n;
 198         char *tcp_device;
 199         nwio_tcpconf_t tcpconf;
 200         nwio_tcpcl_t tcpconnopt;
 201
 202         if ((tcp_device= getenv("TCP_DEVICE")) == nil) tcp_device= "/dev/tcp";
 203
 204         n=60;
 205         for (;;) {
 206             if ((s= open(tcp_device, O_RDWR)) < 0) fatal(tcp_device);
 207
 208             tcpconf.nwtc_flags= NWTC_LP_SEL | NWTC_SET_RA | NWTC_SET_RP;
 209             memcpy(&tcpconf.nwtc_remaddr, hent->h_addr,
 210                 sizeof(tcpconf.nwtc_remaddr));
 211             tcpconf.nwtc_remport= name2port(key);
 212             if (ioctl(s, NWIOSTCPCONF, &tcpconf) < 0) fatal("NWIOSTCPCONF");
 213
 214             tcpconnopt.nwtcl_flags= 0;
 215             if (ioctl(s, NWIOTCPCONN, &tcpconnopt) == 0) break;
 216
 217             if (--n > 0) sleep(2); else fatal("NWIOTCPCONN");
 218             close(s);
 219         }
 220 #else
 221         int n;
 222         struct sockaddr_in channel;
 223
 224         n=60;
 225         for (;;) {
 226             if ((s= socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
 227                 fatal("socket()");
 228
 229             memset(&channel, 0, sizeof(channel));
 230             channel.sin_family= AF_INET;
 231             memcpy(&channel.sin_addr.s_addr, hent->h_addr,
 232                 sizeof(channel.sin_addr.s_addr));
 233             channel.sin_port= name2port(key);
 234             if (connect(s, (struct sockaddr *) &channel,
 235                             sizeof(channel)) >= 0) break;
 236
 237             if (--n > 0) sleep(2); else fatal("connect()");
 238             close(s);
 239         }
 240 #endif
 241     }
 242
 243     if (cmdv[0] != nil) {
 244         /* A command is given, so execute it with standard input (rget),
 245          * standard output (rput) or both (-io) tied to the TCP stream.
 246          */
 247         if (iflag) dup2(s, 0);
 248         if (oflag) dup2(s, 1);
 249         close(s);
 250
 251         execvp(cmdv[0], cmdv);
 252         fatal(cmdv[0]);
 253     } else {
 254         /* Without a command we have to copy bytes ourselves, probably to or
 255          * from a command that is connected to us with a pipe.  (The original
 256          * function of rput/rget, a remote pipe.)
 257          */
 258         int fi, fo;
 259         int n;
 260         char buf[8192];
 261
 262         if (iflag) {
 263             fi= s;
 264             fo= 1;
 265         } else {
 266             fi= 0;
 267             fo= s;
 268         }
 269
 270         while ((n= read(fi, buf, sizeof(buf))) > 0) {
 271             char *bp= buf;
 272
 273             while (n > 0) {
 274                 int r;
 275
 276                 if ((r= write(fo, bp, n)) <= 0) {
 277                     if (r == 0) {
 278                         fprintf(stderr, "%s: write(): Unexpected EOF\n", name);
 279                         exit(1);
 280                     }
 281                     fatal("write()");
 282                 }
 283                 bp+= r;
 284                 n-= r;
 285             }
 286         }
 287         if (n < 0) fatal("read()");
 288     }
 289     return 0;
 290 }