mdw@git.distorted.org.uk Git - tripe/blob - client.c

   1 /* -*-c-*-
   2  *
   3  * $Id: client.c,v 1.6 2001/02/22 09:06:08 mdw Exp $
   4  *
   5  * Client for TrIPE
   6  *
   7  * (c) 2001 Straylight/Edgeware
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of Trivial IP Encryption (TrIPE).
  13  *
  14  * TrIPE is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * TrIPE is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with TrIPE; if not, write to the Free Software Foundation,
  26  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  */
  28
  29 /*----- Revision history --------------------------------------------------*
  30  *
  31  * $Log: client.c,v $
  32  * Revision 1.6  2001/02/22 09:06:08  mdw
  33  * Fix logfile rotation to avoid program collapse.
  34  *
  35  * Revision 1.5  2001/02/16 21:23:39  mdw
  36  * Use reliable signal handling for reopening logs.
  37  *
  38  * Revision 1.4  2001/02/06 09:34:53  mdw
  39  * Change ERR response to FAIL for consistency with other programs.
  40  *
  41  * Revision 1.3  2001/02/04 17:10:15  mdw
  42  * Reopen logfiles on receipt of @SIGHUP@ (not done very well).  Don't
  43  * change directory -- just mangle pathnames instead.
  44  *
  45  * Revision 1.2  2001/02/04 01:17:54  mdw
  46  * Create a configuration header file to tidy up command lines.
  47  *
  48  * Revision 1.1  2001/02/03 20:26:37  mdw
  49  * Initial checkin.
  50  *
  51  */
  52
  53 /*----- Header files ------------------------------------------------------*/
  54
  55 #include "config.h"
  56
  57 #include <ctype.h>
  58 #include <errno.h>
  59 #include <signal.h>
  60 #include <stdio.h>
  61 #include <stdlib.h>
  62 #include <string.h>
  63 #include <time.h>
  64
  65 #include <sys/types.h>
  66 #include <sys/time.h>
  67 #include <unistd.h>
  68 #include <fcntl.h>
  69 #include <sys/wait.h>
  70 #include <syslog.h>
  71
  72 #include <sys/socket.h>
  73 #include <sys/un.h>
  74 #include <arpa/inet.h>
  75 #include <netdb.h>
  76
  77 #include <mLib/alloc.h>
  78 #include <mLib/darray.h>
  79 #include <mLib/dstr.h>
  80 #include <mLib/mdwopt.h>
  81 #include <mLib/quis.h>
  82 #include <mLib/report.h>
  83 #include <mLib/sel.h>
  84 #include <mLib/selbuf.h>
  85 #include <mLib/sig.h>
  86 #include <mLib/str.h>
  87
  88 #include "util.h"
  89
  90 #undef sun
  91
  92 /*----- Data structures ---------------------------------------------------*/
  93
  94 #ifndef STRING_V
  95 #  define STRING_V
  96    DA_DECL(string_v, char *);
  97 #endif
  98
  99 /*----- Static variables --------------------------------------------------*/
 100
 101 static FILE *logfp = 0;
 102 static unsigned f = 0;
 103 static const char *logname = 0;
 104 static int fd;
 105
 106 #define f_bogus 1u
 107 #define f_spawn 2u
 108 #define f_daemon 4u
 109 #define f_spawnopts 8u
 110 #define f_syslog 16u
 111 #define f_command 32u
 112 #define f_noinput 64u
 113 #define f_warn 128u
 114 #define f_uclose 256u
 115
 116 /*----- Main code ---------------------------------------------------------*/
 117
 118 static void reap(int sig)
 119 {
 120   int s;
 121   int e = errno;
 122   while (waitpid(-1, &s, WNOHANG) > 0)
 123     ;
 124   errno = e;
 125 }
 126
 127 static void writelog(const char *cat, const char *msg)
 128 {
 129   char buf[256];
 130   time_t t = time(0);
 131   struct tm *tm = localtime(&t);
 132   strftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S", tm);
 133   fprintf(logfp, "%s %s: %s\n", buf, cat, msg);
 134 }
 135
 136 static void cline(char *p, void *b)
 137 {
 138   char *q;
 139   if (!p) {
 140     if (f & f_command)
 141       die(EXIT_FAILURE, "server dropped the connection");
 142     exit(0);
 143   }
 144   q = str_getword(&p);
 145   if (!q)
 146     return;
 147   if (strcmp(q, "WARN") == 0) {
 148     if (f & f_syslog)
 149       syslog(LOG_WARNING, "%s", p);
 150     if (logfp)
 151       writelog("warning", p);
 152     if (f & f_warn)
 153       fprintf(stderr, "Warning: %s\n", p);
 154   } else if (strcmp(q, "TRACE") == 0) {
 155     if (f & f_syslog)
 156       syslog(LOG_DEBUG, "%s", p);
 157     if (logfp)
 158       writelog("debug", p);
 159   } else if (!(f & f_command)) {
 160     if (f & f_syslog)
 161       syslog(LOG_ERR, "unexpected output `%s %s'", q, p);
 162     if (logfp) {
 163       dstr d = DSTR_INIT;
 164       dstr_putf(&d, "unexpected output `%s %s'", q, p);
 165       writelog("error", d.buf);
 166       dstr_destroy(&d);
 167     }
 168   } else if (strcmp(q, "FAIL") == 0)
 169     die(EXIT_FAILURE, "%s", p);
 170   else if (strcmp(q, "INFO") == 0)
 171     puts(p);
 172   else if (strcmp(q, "OK") == 0)
 173     exit(0);
 174   else
 175     die(EXIT_FAILURE, "unexpected output `%s %s'", q, p);
 176 }
 177
 178 static void sline(char *p, void *b)
 179 {
 180   if (!p) {
 181     if (!(f & f_uclose))
 182       moan("server closed the connection");
 183     exit(0);
 184   }
 185   puts(p);
 186 }
 187
 188 static void uline(char *p, void *b)
 189 {
 190   size_t sz;
 191   if (!p) {
 192     selbuf_destroy(b);
 193     shutdown(fd, 1);
 194     f |= f_uclose;
 195   } else {
 196     sz = strlen(p);
 197     p[sz] = '\n';
 198     write(fd, p, sz + 1);
 199   }
 200 }
 201
 202 static void logfile(const char *name)
 203 {
 204   FILE *fp;
 205
 206   if ((fp = fopen(name, "a")) != 0) {
 207     if (logfp)
 208       fclose(logfp);
 209     logfp =  fp;
 210     setvbuf(logfp, 0, _IOLBF, BUFSIZ);
 211   } else {
 212     dstr d = DSTR_INIT;
 213     dstr_putf(&d, "error opening logfile `%s': %s", name, strerror(errno));
 214     if (logfp)
 215       writelog("error", d.buf);
 216     else if (logname)
 217       die(EXIT_FAILURE, d.buf);
 218     if (f & f_syslog)
 219       syslog(LOG_ERR, d.buf);
 220     dstr_destroy(&d);
 221   }
 222 }
 223
 224 static void sighup(int sig, void *v)
 225 {
 226   logfile(logname);
 227 }
 228
 229 static void version(FILE *fp)
 230 {
 231   pquis(fp, "$, TrIPE version " VERSION "\n");
 232 }
 233
 234 static void usage(FILE *fp)
 235 {
 236   pquis(fp, "\
 237 Usage:\n\
 238         $ [-w] [-options] [command [args]...]\n\
 239         $ [-Dl] [-f file] [-options]\n\
 240 Options:\n\
 241         [-s] [-d directory] [-a socket] [-p program] [-S arg,arg,...]\n\
 242 ");
 243 }
 244
 245 static void help(FILE *fp)
 246 {
 247   version(fp);
 248   fputc('\n', fp);
 249   usage(fp);
 250   fputs("\
 251 \n\
 252 Options in full:\n\
 253 \n\
 254 -h, --help              Show this help text.\n\
 255 -v, --version           Show version number.\n\
 256 -u, --usage             Show brief usage message.\n\
 257 \n\
 258 -D, --daemon            Become a background task after connecting.\n\
 259 -d, --directory=DIR     Select current directory [default /var/lib/tripe]\n\
 260 -a, --admin-socket=FILE Select socket to connect to.\n\
 261 \n\
 262 -s, --spawn             Start server rather than connecting.\n\
 263 -p, --spawn-path=PATH   Specify path to executable.\n\
 264 -S, --spawn-args=ARGS   Specify comma-separated arguments.\n\
 265 \n\
 266 -l, --syslog            Log messages to system log.\n\
 267 -f, --logfile=FILE      Log messages to FILE.\n\
 268 -w, --warnings          Show warnings when running commands.\n\
 269 ", fp);
 270 }
 271
 272 int main(int argc, char *argv[])
 273 {
 274   const char *dir = "/var/lib/tripe";
 275   const char *sock = "tripesock";
 276   const char *spawnpath = "tripe";
 277   string_v spawnopts = DA_INIT;
 278   char *p;
 279
 280   ego(argv[0]);
 281
 282   if ((p = getenv("TRIPEDIR")) != 0)
 283     dir = p;
 284
 285   /* --- Parse the arguments --- */
 286
 287   for (;;) {
 288     static const struct option opts[] = {
 289       { "help",         0,              0,      'h' },
 290       { "version",      0,              0,      'v' },
 291       { "usage",        0,              0,      'u' },
 292       { "daemon",       0,              0,      'D' },
 293       { "directory",    OPTF_ARGREQ,    0,      'd' },
 294       { "admin-socket", OPTF_ARGREQ,    0,      'a' },
 295       { "spawn",        0,              0,      's' },
 296       { "spawn-path",   OPTF_ARGREQ,    0,      'p' },
 297       { "spawn-args",   OPTF_ARGREQ,    0,      'S' },
 298       { "syslog",       0,              0,      'l' },
 299       { "logfile",      OPTF_ARGREQ,    0,      'f' },
 300       { "warnings",     0,              0,      'w' },
 301       { 0,              0,              0,      0 }
 302     };
 303
 304     int i = mdwopt(argc, argv, "hvuDd:a:sp:S:lwf:n", opts, 0, 0, 0);
 305     if (i < 0)
 306       break;
 307     switch (i) {
 308       case 'h':
 309         help(stdout);
 310         exit(0);
 311       case 'v':
 312         version(stdout);
 313         exit(0);
 314       case 'u':
 315         usage(stdout);
 316         exit(0);
 317       case 'D':
 318         f |= f_daemon | f_noinput;
 319         break;
 320       case 'd':
 321         dir = optarg;
 322         break;
 323       case 'a':
 324         sock = optarg;
 325         break;
 326       case 's':
 327         f |= f_spawn;
 328         break;
 329       case 'p':
 330         f |= f_spawn;
 331         spawnpath = optarg;
 332         break;
 333       case 'S':
 334         f |= f_spawn | f_spawnopts;
 335         for (p = strtok(optarg, ","); p; p = strtok(0, ","))
 336           DA_PUSH(&spawnopts, p);
 337         break;
 338       case 'l':
 339         f |= f_syslog | f_noinput;
 340         break;
 341       case 'w':
 342         f |= f_warn;
 343         break;
 344       case 'f':
 345         logname = optarg;
 346         logfile(logname);
 347         f |= f_noinput;
 348         break;
 349       default:
 350         f |= f_bogus;
 351         break;
 352     }
 353   }
 354   if ((f & f_bogus) || ((f & f_noinput) && optind < argc)) {
 355     usage(stderr);
 356     exit(EXIT_FAILURE);
 357   }
 358
 359   /* --- Connect to the server --- */
 360
 361   if (f & f_spawn) {
 362     int pfd[2];
 363     pid_t kid;
 364     struct sigaction sa;
 365     sigset_t newmask, oldmask;
 366
 367     sa.sa_handler = reap;
 368     sigemptyset(&sa.sa_mask);
 369     sa.sa_flags = SA_NOCLDSTOP;
 370 #ifdef SA_RESTART
 371     sa.sa_flags |= SA_RESTART;
 372 #endif
 373     sigaction(SIGCHLD, &sa, 0);
 374
 375     DA_UNSHIFT(&spawnopts, (char *)spawnpath);
 376     if (!(f & f_spawnopts)) {
 377       DA_PUSH(&spawnopts, "-d");
 378       DA_PUSH(&spawnopts, (char *)dir);
 379       DA_PUSH(&spawnopts, "-a");
 380       DA_PUSH(&spawnopts, (char *)sock);
 381     }
 382     DA_PUSH(&spawnopts, 0);
 383     if (socketpair(PF_UNIX, SOCK_STREAM, 0, pfd))
 384       die(EXIT_FAILURE, "error from socketpair: %s", strerror(errno));
 385     sigemptyset(&newmask);
 386     sigaddset(&newmask, SIGCHLD);
 387     sigprocmask(SIG_BLOCK, &newmask, &oldmask);
 388     if ((kid = fork()) < 0)
 389       die(EXIT_FAILURE, "fork failed: %s", strerror(errno));
 390     if (!kid) {
 391       dup2(pfd[1], STDIN_FILENO);
 392       dup2(pfd[1], STDOUT_FILENO);
 393       close(pfd[1]);
 394       close(pfd[0]);
 395       if (logfp)
 396         fclose(logfp);
 397       closelog();
 398       execvp(DA(&spawnopts)[0], DA(&spawnopts));
 399       die(127, "couldn't exec `%s': %s", spawnpath, strerror(errno));
 400     }
 401     sigprocmask(SIG_SETMASK, &oldmask, 0);
 402     fd = pfd[0];
 403     close(pfd[1]);
 404   } else {
 405     struct sockaddr_un sun;
 406     size_t sz = strlen(sock) + 1;
 407     dstr d = DSTR_INIT;
 408     dstr_putf(&d, "%s/%s", dir, sock);
 409     if (d.sz + 1 > sizeof(sun.sun_path))
 410       die(EXIT_FAILURE, "socket name `%s' too long", sock);
 411     memset(&sun, 0, sizeof(sun));
 412     sun.sun_family = AF_UNIX;
 413     memcpy(sun.sun_path, d.buf, d.sz + 1);
 414     sz = d.sz + offsetof(struct sockaddr_un, sun_path) + 1;
 415     dstr_destroy(&d);
 416     if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
 417       die(EXIT_FAILURE, "error making socket: %s", strerror(errno));
 418     if (connect(fd, (struct sockaddr *)&sun, sz)) {
 419       die(EXIT_FAILURE, "error connecting to `%s': %s",
 420           sun.sun_path, strerror(errno));
 421     }
 422   }
 423
 424   if (f & f_daemon) {
 425     if (u_daemon())
 426       die(EXIT_FAILURE, "error becoming daemon: %s", strerror(errno));
 427   }
 428
 429   /* --- If we're meant to be interactive, do that --- */
 430
 431   if (!(f & f_noinput) && optind == argc) {
 432     sel_state sel;
 433     selbuf bu, bs;
 434
 435     sel_init(&sel);
 436     selbuf_init(&bu, &sel, STDIN_FILENO, uline, &bu);
 437     selbuf_init(&bs, &sel, fd, sline, &bs);
 438     for (;;) {
 439       if (sel_select(&sel) && errno != EINTR && errno != EAGAIN)
 440         die(EXIT_FAILURE, "select failed: %s", strerror(errno));
 441     }
 442   }
 443
 444   /* --- If there's a command, submit it --- */
 445
 446   if (optind < argc) {
 447     dstr d = DSTR_INIT;
 448     dstr_puts(&d, argv[optind++]);
 449     while (optind < argc) {
 450       dstr_putc(&d, ' ');
 451       dstr_puts(&d, argv[optind++]);
 452     }
 453     dstr_putc(&d, '\n');
 454     write(fd, d.buf, d.len);
 455     shutdown(fd, 1);
 456     dstr_destroy(&d);
 457     f |= f_command;
 458   }
 459
 460   /* --- Pull everything else out of the box --- */
 461
 462   {
 463     sel_state sel;
 464     selbuf b;
 465     sig hup;
 466
 467     sel_init(&sel);
 468     selbuf_init(&b, &sel, fd, cline, 0);
 469
 470     if (f & f_syslog)
 471       openlog(QUIS, 0, LOG_DAEMON);
 472     if (logfp) {
 473       sig_init(&sel);
 474       sig_add(&hup, SIGHUP, sighup, 0);
 475     }
 476     for (;;) {
 477       if (sel_select(&sel) && errno != EINTR && errno != EAGAIN)
 478         die(EXIT_FAILURE, "select failed: %s", strerror(errno));
 479     }
 480   }
 481
 482   return (0);
 483 }
 484
 485 /*----- That's all, folks -------------------------------------------------*/