common/dumprmt.c

   1 /*
   2  *      Ported to Linux's Second Extended File System as part of the
   3  *      dump and restore backup suit
   4  *      Remy Card <card@Linux.EU.Org>, 1994-1997
   5  *      Stelian Pop <stelian@popies.net>, 1999-2000
   6  *      Stelian Pop <stelian@popies.net> - Alcôve <www.alcove.com>, 2000-2002
   7  */
   8
   9 /*-
  10  * Copyright (c) 1980, 1993
  11  *      The Regents of the University of California.  All rights reserved.
  12  *
  13  * Redistribution and use in source and binary forms, with or without
  14  * modification, are permitted provided that the following conditions
  15  * are met:
  16  * 1. Redistributions of source code must retain the above copyright
  17  *    notice, this list of conditions and the following disclaimer.
  18  * 2. Redistributions in binary form must reproduce the above copyright
  19  *    notice, this list of conditions and the following disclaimer in the
  20  *    documentation and/or other materials provided with the distribution.
  21  * 3. Neither the name of the University nor the names of its contributors
  22  *    may be used to endorse or promote products derived from this software
  23  *    without specific prior written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  35  * SUCH DAMAGE.
  36  */
  37
  38 #ifndef lint
  39 static const char rcsid[] =
  40         "$Id: dumprmt.c,v 1.29 2006/03/13 10:33:44 stelian Exp $";
  41 #endif /* not lint */
  42
  43 #include <config.h>
  44 #include <sys/param.h>
  45 #include <sys/mtio.h>
  46 #include <sys/socket.h>
  47 #include <sys/time.h>
  48 #include <fcntl.h>
  49 #ifdef __linux__
  50 #include <sys/types.h>
  51 #ifdef HAVE_EXT2FS_EXT2_FS_H
  52 #include <ext2fs/ext2_fs.h>
  53 #else
  54 #include <linux/ext2_fs.h>
  55 #endif
  56 #include <bsdcompat.h>
  57 #include <signal.h>
  58 #elif defined sunos
  59 #include <sys/vnode.h>
  60
  61 #include <ufs/inode.h>
  62 #else
  63 #include <ufs/ufs/dinode.h>
  64 #endif
  65
  66 #include <netinet/in.h>
  67 #include <netinet/in_systm.h>
  68 #include <netinet/ip.h>
  69 #include <netinet/tcp.h>
  70
  71 #include <protocols/dumprestore.h>
  72
  73 #include <ctype.h>
  74 #include <errno.h>
  75 #include <compaterr.h>
  76 #include <rmtflags.h>
  77 #include <netdb.h>
  78 #include <pwd.h>
  79 #include <stdio.h>
  80 #ifdef __STDC__
  81 #include <stdlib.h>
  82 #include <string.h>
  83 #include <unistd.h>
  84 #endif
  85
  86 #ifdef  __linux__
  87 #include <ext2fs/ext2fs.h>
  88 #endif
  89
  90 #include <pathnames.h>
  91 #include "dump.h"       /* for X_STARTUP, X_ABORT etc */
  92
  93 #define TS_CLOSED       0
  94 #define TS_OPEN         1
  95
  96 static  int rmtstate = TS_CLOSED;
  97 static  int tormtape = -1;
  98 static  int fromrmtape = -1;
  99 int rshpid = -1;
 100 static  const char *rmtpeer = 0;
 101
 102 static  int okname __P((const char *));
 103 static  OFF_T rmtcall __P((const char *, const char *));
 104 static  void rmtconnaborted __P((int));
 105 static  int rmtgetb __P((void));
 106 static  int rmtgetconn __P((void));
 107 static  void rmtgets __P((char *, size_t));
 108 static  OFF_T rmtreply __P((const char *));
 109 static  int piped_child __P((const char **command));
 110 #ifdef KERBEROS
 111 int     krcmd __P((char **, int /*u_short*/, char *, char *, int *, char *));
 112 #endif
 113
 114 static  int errfd = -1;
 115 extern  int dokerberos;
 116 extern  int ntrec;              /* blocking factor on tape */
 117 extern  int abortifconnerr;     /* set to 1 if this lib should exit on connection errors
 118                                 otherwise just print a message using msg */
 119 #ifndef errno
 120 extern  int errno;
 121 #endif
 122
 123 int
 124 rmthost(const char *host)
 125 {
 126         if (rmtpeer)
 127                 free((void *)rmtpeer);
 128         if ((rmtpeer = strdup(host)) == NULL)
 129                 rmtpeer = host;
 130         signal(SIGPIPE, rmtconnaborted);
 131         return rmtgetconn();
 132 }
 133
 134 static void
 135 rmtconnaborted(UNUSED(int signo))
 136 {
 137         msg("Lost connection to remote host.\n");
 138         if (errfd != -1) {
 139                 fd_set r;
 140                 struct timeval t;
 141
 142                 FD_ZERO(&r);
 143                 FD_SET(errfd, &r);
 144                 t.tv_sec = 0;
 145                 t.tv_usec = 0;
 146                 if (select(errfd + 1, &r, NULL, NULL, &t)) {
 147                         int i;
 148                         char buf[2048];
 149
 150                         if ((i = read(errfd, buf, sizeof(buf) - 1)) > 0) {
 151                                 buf[i] = '\0';
 152                                 msg("on %s: %s%s", rmtpeer, buf,
 153                                         buf[i - 1] == '\n' ? "" : "\n");
 154                         }
 155                 }
 156         }
 157         if (abortifconnerr)
 158                 exit(X_ABORT);
 159 }
 160
 161 static int
 162 rmtgetconn(void)
 163 {
 164         char *cp;
 165         const char *rmt;
 166         static struct servent *sp = NULL;
 167         static struct passwd *pwd = NULL;
 168         const char *tuser;
 169         const char *rsh;
 170         int size;
 171         int throughput;
 172         int on;
 173         char *rmtpeercopy;
 174
 175         rsh = getenv("RSH");
 176
 177         if (!rsh && sp == NULL) {
 178                 sp = getservbyname(dokerberos ? "kshell" : "shell", "tcp");
 179                 if (sp == NULL) {
 180                         if (abortifconnerr) {
 181                                 errx(1, "%s/tcp: unknown service", dokerberos ? "kshell" : "shell");
 182                         } else {
 183                                 msg("%s/tcp: unknown service", dokerberos ? "kshell" : "shell");
 184                                 return 0;
 185                         }
 186                 }
 187         }
 188         if (pwd == NULL) {
 189                 pwd = getpwuid(getuid());
 190                 if (pwd == NULL) {
 191                         if (abortifconnerr) {
 192                                 errx(1, "who are you?");
 193                         } else {
 194                                 msg("who are you?");
 195                                 return 0;
 196                         }
 197                 }
 198         }
 199         if ((cp = strchr(rmtpeer, '@')) != NULL) {
 200                 tuser = rmtpeer;
 201                 *cp = '\0';
 202                 if (!okname(tuser)) {
 203                         if (abortifconnerr) {
 204                                 exit(X_STARTUP);
 205                         } else {
 206                                 return 0;
 207                         }
 208                 }
 209                 rmtpeer = ++cp;
 210         } else
 211                 tuser = pwd->pw_name;
 212         if ((rmt = getenv("RMT")) == NULL)
 213                 rmt = _PATH_RMT;
 214         msg("");
 215
 216         if (rsh) {
 217                 const char *rshcmd[6];
 218                 rshcmd[0] = rsh;
 219                 rshcmd[1] = rmtpeer;
 220                 rshcmd[2] = "-l";
 221                 rshcmd[3] = tuser;
 222                 rshcmd[4] = rmt;
 223                 rshcmd[5] = NULL;
 224
 225                 /* Restore the uid and gid. We really don't want
 226                  * to execute whatever is put into RSH variable with
 227                  * more priviledges than needed... */
 228                 setuid(getuid());
 229                 setgid(getgid());
 230
 231                 if ((rshpid = piped_child(rshcmd)) < 0) {
 232                         msg("cannot open connection\n");
 233                         return 0;
 234                 }
 235         }
 236         else {
 237                 /* Copy rmtpeer to rmtpeercopy to ignore the
 238                    return value from rcmd. I cannot figure if
 239                    this is this a bug in rcmd or in my code... */
 240                 rmtpeercopy = (char *)rmtpeer;
 241 #ifdef KERBEROS
 242                 if (dokerberos)
 243                         tormtape = krcmd(&rmtpeercopy, sp->s_port, tuser, rmt, &errfd,
 244                                        (char *)0);
 245                 else
 246 #endif
 247                         tormtape = rcmd(&rmtpeercopy, (u_short)sp->s_port, pwd->pw_name,
 248                                       tuser, rmt, &errfd);
 249                 if (tormtape < 0) {
 250                         msg("login to %s as %s failed.\n", rmtpeer, tuser);
 251                         return 0;
 252                 }
 253                 size = ntrec * TP_BSIZE;
 254                 if (size > 60 * 1024)           /* XXX */
 255                         size = 60 * 1024;
 256                 /* Leave some space for rmt request/response protocol */
 257                 size += 2 * 1024;
 258                 while (size > TP_BSIZE &&
 259                     setsockopt(tormtape, SOL_SOCKET, SO_SNDBUF, &size, sizeof (size)) < 0)
 260                             size -= TP_BSIZE;
 261                 (void)setsockopt(tormtape, SOL_SOCKET, SO_RCVBUF, &size, sizeof (size));
 262                 throughput = IPTOS_THROUGHPUT;
 263                 if (setsockopt(tormtape, IPPROTO_IP, IP_TOS,
 264                     &throughput, sizeof(throughput)) < 0)
 265                         perror("IP_TOS:IPTOS_THROUGHPUT setsockopt");
 266                 on = 1;
 267                 if (setsockopt(tormtape, IPPROTO_TCP, TCP_NODELAY, &on, sizeof (on)) < 0)
 268                         perror("TCP_NODELAY setsockopt");
 269                 fromrmtape = tormtape;
 270         }
 271         (void)fprintf(stderr, "Connection to %s established.\n", rmtpeer);
 272         return 1;
 273 }
 274
 275 static int
 276 okname(const char *cp0)
 277 {
 278         const char *cp;
 279         int c;
 280
 281         for (cp = cp0; *cp; cp++) {
 282                 c = *cp;
 283                 if (!isascii(c) || !(isalnum(c) || c == '_' || c == '-')) {
 284                         warnx("invalid user name %s\n", cp0);
 285                         return (0);
 286                 }
 287         }
 288         return (1);
 289 }
 290
 291 int
 292 rmtopen(const char *tape, const int mode)
 293 {
 294         char buf[MAXPATHLEN];
 295         char *rmtflags;
 296
 297         rmtflags = rmtflags_tochar(mode);
 298         (void)snprintf(buf, sizeof (buf), "O%s\n%d %s\n",
 299                        tape,
 300                        mode & O_ACCMODE,
 301                        rmtflags);
 302         free(rmtflags);
 303         rmtstate = TS_OPEN;
 304         return (rmtcall(tape, buf));
 305 }
 306
 307 void
 308 rmtclose(void)
 309 {
 310
 311         if (rmtstate != TS_OPEN)
 312                 return;
 313         rmtcall("close", "C\n");
 314         rmtstate = TS_CLOSED;
 315 }
 316
 317 int
 318 rmtread(char *buf, size_t count)
 319 {
 320         char line[30];
 321         int n, i;
 322         ssize_t cc;
 323
 324         (void)snprintf(line, sizeof (line), "R%u\n", (unsigned)count);
 325         n = rmtcall("read", line);
 326         if (n < 0) {
 327                 /* rmtcall() properly sets errno for us on errors. */
 328                 errno = n;
 329                 return (-1);
 330         }
 331         for (i = 0; i < n; i += cc) {
 332                 cc = read(fromrmtape, buf+i, n - i);
 333                 if (cc <= 0)
 334                         rmtconnaborted(0);
 335         }
 336         return (n);
 337 }
 338
 339 int
 340 rmtwrite(const char *buf, size_t count)
 341 {
 342         char line[30];
 343
 344         (void)snprintf(line, sizeof (line), "W%ld\n", (long)count);
 345         write(tormtape, line, strlen(line));
 346         write(tormtape, buf, count);
 347         return (rmtreply("write"));
 348 }
 349
 350 OFF_T
 351 rmtseek(OFF_T offset, int pos)
 352 {
 353         char line[80];
 354
 355         (void)snprintf(line, sizeof (line), "L%lld\n%d\n", (long long)offset, pos);
 356         return (rmtcall("seek", line));
 357 }
 358
 359 struct  mtget mts;
 360
 361 struct mtget *
 362 rmtstatus(void)
 363 {
 364         int i;
 365         char *cp;
 366
 367         if (rmtstate != TS_OPEN)
 368                 return (NULL);
 369         i = rmtcall("status", "S");
 370         if (i < 0) return NULL;
 371         if (i != (int)sizeof(mts)) {
 372                 msg("mtget sizes different between host (%d) "
 373                     "and remote tape (%d)", sizeof(mts), i);
 374                 for ( /* empty */; i > 0; --i)
 375                         rmtgetb();
 376                 return NULL;
 377         }
 378         for (i = 0, cp = (char *)&mts; i < (int)sizeof(mts); i++)
 379                 *cp++ = rmtgetb();
 380         return (&mts);
 381 }
 382
 383 int
 384 rmtioctl(int cmd, int count)
 385 {
 386         char buf[256];
 387
 388         if (count < 0)
 389                 return (-1);
 390         (void)snprintf(buf, sizeof (buf), "I%d\n%d\n", cmd, count);
 391         return (rmtcall("ioctl", buf));
 392 }
 393
 394 static OFF_T
 395 rmtcall(const char *cmd, const char *buf)
 396 {
 397
 398         if (write(tormtape, buf, strlen(buf)) != (ssize_t)strlen(buf))
 399                 rmtconnaborted(0);
 400         return (rmtreply(cmd));
 401 }
 402
 403 static OFF_T
 404 rmtreply(const char *cmd)
 405 {
 406         char *cp;
 407         char code[30], emsg[BUFSIZ];
 408
 409         rmtgets(code, sizeof (code));
 410         if (*code == 'E' || *code == 'F') {
 411                 rmtgets(emsg, sizeof (emsg));
 412                 msg("%s: %s", cmd, emsg);
 413                 errno = atoi(code + 1);
 414                 if (*code == 'F')
 415                         rmtstate = TS_CLOSED;
 416                 return (-1);
 417         }
 418         if (*code != 'A') {
 419                 /* Kill trailing newline */
 420                 cp = code + strlen(code);
 421                 if (cp > code && *--cp == '\n')
 422                         *cp = '\0';
 423
 424                 msg("Protocol to remote tape server botched (code \"%s\").\n",
 425                     code);
 426                 rmtconnaborted(0);
 427         }
 428         return (OFF_T)(atoll(code + 1));
 429 }
 430
 431 static int
 432 rmtgetb(void)
 433 {
 434         char c;
 435
 436         if (read(fromrmtape, &c, 1) != 1)
 437                 rmtconnaborted(0);
 438         return (c);
 439 }
 440
 441 /* Get a line (guaranteed to have a trailing newline). */
 442 static void
 443 rmtgets(char *line, size_t len)
 444 {
 445         char *cp = line;
 446
 447         while (len > 1) {
 448                 *cp = rmtgetb();
 449                 if (*cp == '\n') {
 450                         cp[1] = '\0';
 451                         return;
 452                 }
 453                 cp++;
 454                 len--;
 455         }
 456         *cp = '\0';
 457         msg("Protocol to remote tape server botched.\n");
 458         msg("(rmtgets got \"%s\").\n", line);
 459         rmtconnaborted(0);
 460 }
 461
 462 int piped_child(const char **command) {
 463         int pid;
 464         int to_child_pipe[2];
 465         int from_child_pipe[2];
 466
 467         if (pipe (to_child_pipe) < 0) {
 468                 msg ("cannot create pipe: %s\n", strerror(errno));
 469                 return -1;
 470         }
 471         if (pipe (from_child_pipe) < 0) {
 472                 msg ("cannot create pipe: %s\n", strerror(errno));
 473                 return -1;
 474         }
 475         pid = fork ();
 476         if (pid < 0) {
 477                 msg ("cannot fork: %s\n", strerror(errno));
 478                 return -1;
 479         }
 480         if (pid == 0) {
 481                 if (dup2 (to_child_pipe[0], STDIN_FILENO) < 0) {
 482                         msg ("cannot dup2 pipe: %s\n", strerror(errno));
 483                         exit(1);
 484                 }
 485                 if (close (to_child_pipe[1]) < 0) {
 486                         msg ("cannot close pipe: %s\n", strerror(errno));
 487                         exit(1);
 488                 }
 489                 if (close (from_child_pipe[0]) < 0) {
 490                         msg ("cannot close pipe: %s\n", strerror(errno));
 491                         exit(1);
 492                 }
 493                 if (dup2 (from_child_pipe[1], STDOUT_FILENO) < 0) {
 494                         msg ("cannot dup2 pipe: %s\n", strerror(errno));
 495                         exit(1);
 496                 }
 497                 setpgid(0, getpid());
 498                 execvp (command[0], (char *const *) command);
 499                 msg("cannot exec %s: %s\n", command[0], strerror(errno));
 500                 exit(1);
 501         }
 502         if (close (to_child_pipe[0]) < 0) {
 503                 msg ("cannot close pipe: %s\n", strerror(errno));
 504                 return -1;
 505         }
 506         if (close (from_child_pipe[1]) < 0) {
 507                 msg ("cannot close pipe: %s\n", strerror(errno));
 508                 return -1;
 509         }
 510         tormtape = to_child_pipe[1];
 511         fromrmtape = from_child_pipe[0];
 512         return pid;
 513 }