usr/src/cmd/mail/main.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  28 /*        All Rights Reserved   */
  29
  30 #pragma ident   "%Z%%M% %I%     %E% SMI"
  31
  32 #include "mail.h"
  33 #ifdef SVR4
  34 #include <locale.h>
  35 #endif
  36 /*
  37  *      mail [ -ehpPqrtw ] [-x debuglevel] [ -f file ] [ -F user(s) ]
  38  *      mail -T file persons
  39  *      mail [ -tw ] [ -m messagetype ] persons
  40  *      rmail [ -tw ] persons
  41  */
  42 int
  43 main(int argc, char **argv)
  44 {
  45         register int i;
  46         char *cptr, *p;
  47         struct stat statb;
  48         static char pn[] = "main";
  49         extern char **environ;
  50         int env_var_idx, next_slot_idx;
  51         int tmpfd = -1;
  52
  53 #ifdef SVR4
  54         (void) setlocale(LC_ALL, "");
  55 #endif
  56         /* fix here for bug #1086130 - security hole    */
  57         /* skip over the LD_* env variable              */
  58         env_var_idx = 0; next_slot_idx = 0;
  59         while (environ[env_var_idx] != NULL) {
  60                         environ[next_slot_idx] = environ[env_var_idx];
  61                 if (strncmp(environ[env_var_idx], "LD_", 3)) {
  62                         next_slot_idx++;
  63                 }
  64                 env_var_idx++;
  65         }
  66         environ[next_slot_idx] = NULL;
  67
  68 #ifdef SIGCONT
  69 #ifdef SVR4
  70         {
  71         struct sigaction nsig;
  72         nsig.sa_handler = SIG_DFL;
  73         sigemptyset(&nsig.sa_mask);
  74         nsig.sa_flags = SA_RESTART;
  75         (void) sigaction(SIGCONT, &nsig, NULL);
  76         }
  77 #else
  78         sigset(SIGCONT, SIG_DFL);
  79 #endif
  80 #endif
  81
  82         /*
  83          *      Strip off path name of this command for use in messages
  84          */
  85         if ((program = strrchr(argv[0], '/')) != NULL) {
  86                 program++;
  87         } else {
  88                 program = argv[0];
  89         }
  90
  91         /* Close all file descriptors except stdin, stdout & stderr */
  92         closefrom(STDERR_FILENO + 1);
  93
  94         /*
  95          *      Get group id for mail, exit if none exists
  96          */
  97         if ((grpptr = getgrnam("mail")) == NULL) {
  98                 errmsg(E_GROUP, "");
  99                 exit(1);
 100         } else {
 101                 mailgrp = grpptr->gr_gid;
 102         }
 103
 104         /*
 105          *      Save the *id for later use.
 106          */
 107         my_uid = getuid();
 108         my_gid = getgid();
 109         my_euid = geteuid();
 110         my_egid = getegid();
 111
 112         /*
 113          *      What command (rmail or mail)?
 114          */
 115         if (strcmp(program, "rmail") == SAME) {
 116                 ismail = FALSE;
 117         }
 118
 119         /*
 120          *      Parse the command line and adjust argc and argv
 121          *      to compensate for any options
 122          */
 123         i = parse(argc, argv);
 124         argv += (i - 1);
 125         argc -= (i - 1);
 126
 127         /* block a potential security hole */
 128         if (flgT && (my_euid != 0)) {
 129                 setgid(my_gid);
 130                 Tout(pn, "Setgid unset\n");
 131         }
 132
 133         if (debug == 0) {
 134                 /* If not set as an invocation option, check for system-wide */
 135                 /* global flag */
 136                 char *xp = xgetenv("DEBUG");
 137                 if (xp != NULL) {
 138                         debug = atoi(xp);
 139                         if (debug < 0) {
 140                                 /* Keep trace file even if successful */
 141                                 keepdbgfile = -1;
 142                                 debug = -debug;
 143                         }
 144                 }
 145         }
 146         if (debug > 0) {
 147                 strcpy(dbgfname, "/tmp/MLDBGXXXXXX");
 148                 if ((tmpfd = mkstemp(dbgfname)) == -1) {
 149                         fprintf(stderr, "%s: can't open debugging file '%s'\n",
 150                                 program, dbgfname);
 151                         exit(13);
 152                 }
 153                 if ((dbgfp = fdopen(tmpfd, "w")) == NULL) {
 154                         fprintf(stderr, "%s: can't open debugging file '%s'\n",
 155                                 program, dbgfname);
 156                         (void) close(tmpfd);
 157                         exit(13);
 158                 }
 159                 setbuf(dbgfp, NULL);
 160                 fprintf(dbgfp, "main(): debugging level == %d\n", debug);
 161                 fprintf(dbgfp, "main(): trace file ='%s': kept %s\n", dbgfname,
 162                         ((keepdbgfile < 0) ?
 163                                 "on success or failure." : "only on failure."));
 164         }
 165
 166         if (!ismail && (goerr > 0 || !i)) {
 167                 Dout(pn, 11, "!ismail, goerr=%d, i=%d\n", goerr, i);
 168                 if (goerr > 0) {
 169                         errmsg(E_SYNTAX, "Usage: rmail [-wt] person(s)");
 170                 }
 171                 if (!i) {
 172                         errmsg(E_SYNTAX, "At least one user must be specified");
 173                 }
 174                 Dout(pn, 11, "exiting!\n");
 175                 done(0);
 176         }
 177
 178         umsave = umask(7);
 179         uname(&utsn);
 180         if ((p = xgetenv("CLUSTER")) != NULL) {
 181                 /*
 182                  * We are not who we appear...
 183                  */
 184                 thissys = p;
 185         } else {
 186                 thissys = utsn.nodename;
 187         }
 188         Dout(pn, 11, "thissys = '%s', uname = '%s'\n", thissys, utsn.nodename);
 189
 190         failsafe = xgetenv("FAILSAFE");
 191         if (failsafe)
 192                 Dout(pn, 11, "failsafe processing enabled to %s\n", failsafe);
 193
 194         /*
 195          *      Use environment variables
 196          */
 197         home = getenv("HOME");
 198         if (!home || !*home) {
 199                 home = ".";
 200         }
 201
 202         my_name[0] = '\0';
 203         pwd = getpwuid(my_uid);
 204         if (pwd)
 205                 (void) strlcpy(my_name, pwd->pw_name, sizeof (my_name));
 206
 207         /* If root, use LOGNAME if set */
 208         if (my_uid == 0) {
 209                 /* If root, use LOGNAME if set */
 210                 if (((cptr = getenv("LOGNAME")) != NULL) &&
 211                     (strlen(cptr) != 0)) {
 212                         (void) strlcpy(my_name, cptr, sizeof (my_name));
 213                 }
 214         }
 215         Dout(pn, 11, "my_name = '%s'\n", my_name);
 216
 217         /*
 218          *      Catch signals for cleanup
 219          */
 220         if (setjmp(sjbuf)) {
 221                 done(0);
 222         }
 223         for (i = SIGINT; i < SIGCLD; i++) {
 224                 setsig(i, delete);
 225         }
 226         setsig(SIGHUP, sig_done);
 227         setsig(SIGTERM, sig_done);
 228
 229         cksaved(my_name);
 230
 231         /*
 232          *      Rmail is always invoked to send mail
 233          */
 234         Dout(pn, 11, "ismail=%d, argc=%d\n", ismail, argc);
 235         if (ismail && (argc == 1)) {
 236                 sending = FALSE;
 237                 printmail();
 238
 239         } else {
 240                 sending = TRUE;
 241                 sendmail(argc, argv);
 242         }
 243         done(0);
 244 }