src/modules/mail.c

   1 /*
   2     Copyright (C) 2001-2011 Ben Kibbey <bjk@luxsci.net>
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02110-1301  USA
  17 */
  18 #ifdef HAVE_CONFIG_H
  19 #include <config.h>
  20 #endif
  21
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <unistd.h>
  25 #include <sys/types.h>
  26 #include <sys/stat.h>
  27 #include <errno.h>
  28 #include <pwd.h>
  29
  30 #ifdef HAVE_FCNTL_H
  31 #include <fcntl.h>
  32 #endif
  33
  34 #ifdef HAVE_STRING_H
  35 #include <string.h>
  36 #endif
  37
  38 #ifdef HAVE_LIMITS_H
  39 #include <limits.h>
  40 #endif
  41
  42 #ifdef HAVE_SYS_MMAN_H
  43 #include <sys/mman.h>
  44 #endif
  45
  46 #ifdef HAVE_ERR_H
  47 #include <err.h>
  48 #endif
  49
  50 #ifdef HAVE_PATHS_H
  51 #include <paths.h>
  52 #endif
  53 #ifndef _PATH_MAILDIR
  54 #define _PATH_MAILDIR           "/var/mail"
  55 #endif
  56
  57 #ifndef HAVE_ERR_H
  58 #include "../err.c"
  59 #endif
  60
  61 #ifndef HAVE_STRSEP
  62 #include "../strsep.c"
  63 #endif
  64
  65 #ifdef WITH_DMALLOC
  66 #include <dmalloc.h>
  67 #endif
  68
  69 #define MAIL_OPTION_ORDER       "smrfa"
  70 #define MAIL_OPTION_STRING      "Mfrsam"
  71
  72 static char options[6];         /* NULL terminated. */
  73 static char *aliasbuf;
  74 static char **strings;
  75
  76 void add_string(char ***, const char *);
  77 char *stamp(time_t, const char *);
  78 char *safe_strncat(char *, const char *, size_t);
  79
  80 void ui_module_init(int *chainable)
  81 {
  82     *chainable = 0;
  83 }
  84
  85 void ui_module_exit()
  86 {
  87     if (aliasbuf)
  88         munmap(aliasbuf, strlen(aliasbuf));
  89
  90     aliasbuf = NULL;
  91 }
  92
  93 /* Remove characters (rm) from string (str). */
  94 static char *stripstr(char *str, char *rm)
  95 {
  96     static char buf[LINE_MAX];
  97     char *orm;
  98     int i = 0;
  99
 100     if (rm == NULL || str == NULL)
 101         return str;
 102
 103     while (*str) {
 104         orm = rm;
 105
 106         while (*orm) {
 107             if (*str == *orm) {
 108                 str++;
 109                 continue;
 110             }
 111
 112             orm++;
 113         }
 114
 115         buf[i++] = *str++;
 116     }
 117
 118     buf[i] = '\0';
 119     return buf;
 120 }
 121
 122 /* Return a string of mail aliases for the user. Looks in /etc/aliases (or
 123  * whatever was specified at compile-time). The file is read into a buffer
 124  * only once (mmap(2)). */
 125 static char *mail_aliases(const char *user, const int multi)
 126 {
 127     char t[LINE_MAX];
 128     static char aliases[LINE_MAX], *p;
 129     static int firstrun;
 130     int i, n;
 131     struct stat st;
 132     char m[2] = { multi, '\0' };
 133     int fd;
 134
 135     aliases[0] = '\0';
 136
 137     if ((!aliasbuf && firstrun) || aliasbuf == MAP_FAILED)
 138         return "!";
 139
 140     if (!aliasbuf) {
 141         firstrun = 1;
 142
 143         if (stat(ALIAS_FILE, &st) == -1)
 144             return "!";
 145
 146         if ((fd = open(ALIAS_FILE, O_RDONLY)) == -1)
 147             return "!";
 148
 149         if ((aliasbuf = mmap(0, st.st_size, PROT_READ, MAP_PRIVATE, fd,
 150                              0)) == MAP_FAILED) {
 151             warn("%s", "mmap()");
 152             return "!";
 153         }
 154
 155         close(fd);
 156     }
 157
 158     for (i = n = 0; aliasbuf[i]; i++) {
 159         char *last, *name, *tmp;
 160
 161         while (aliasbuf[i] != '\n')
 162             t[n++] = aliasbuf[i++];
 163
 164         t[n] = 0;
 165         n = 0;
 166
 167         if (t[0] == '#' || t[0] == '\0')
 168             continue;
 169
 170         last = t;
 171
 172         if ((name = strsep(&last, ":")) == NULL)
 173             continue;
 174
 175         if (strcmp(user, name) == 0) {
 176             while ((tmp = strsep(&last, ",")) != NULL) {
 177                 tmp = stripstr(tmp, " \n\t");
 178
 179                 safe_strncat(aliases, tmp, sizeof(aliases));
 180                 safe_strncat(aliases, m, sizeof(aliases));
 181             }
 182
 183             continue;
 184         }
 185
 186         while ((tmp = strsep(&last, ",")) != NULL) {
 187             tmp = stripstr(tmp, " \n\t");
 188
 189             if (strcmp(user, tmp) == 0) {
 190                 safe_strncat(aliases, name, sizeof(aliases));
 191                 safe_strncat(aliases, m, sizeof(aliases));
 192             }
 193         }
 194     }
 195
 196     if (aliases[0] == '\0')
 197         return "-";
 198     else
 199         aliases[strlen(aliases) - 1] = '\0';
 200
 201     p = aliases;
 202     return p;
 203 }
 204
 205 /* Returns a string of forward aliases for the user. Reads ~/.forward if it
 206  * exists and is readable. */
 207 static char *forwards(const char *dir, const int multi)
 208 {
 209     FILE *fp;
 210     char buf[LINE_MAX], *s;
 211     static char buf2[LINE_MAX];
 212     int n = 0;
 213     char m[2] = { multi, '\0' };
 214
 215     snprintf(buf2, sizeof(buf2), "%s/.forward", dir);
 216
 217     if ((fp = fopen(buf2, "r")) == NULL) {
 218         if (errno == ENOENT)
 219             return "-";
 220         else
 221             return "!";
 222     }
 223
 224     buf2[0] = '\0';
 225
 226     while ((s = fgets(buf, sizeof(buf), fp)) != NULL) {
 227         if (buf[0] == '\n')
 228             continue;
 229
 230         if (buf[strlen(buf) - 1] == '\n')
 231             buf[strlen(buf) - 1] = '\0';
 232
 233         if (n++)
 234             safe_strncat(buf2, m, sizeof(buf2));
 235
 236         safe_strncat(buf2, buf, sizeof(buf2));
 237     }
 238
 239     fclose(fp);
 240
 241     if (!n)
 242         return "-";
 243
 244     s = buf2;
 245     return s;
 246 }
 247
 248 /* /var/mail/username folder size in bytes. */
 249 static char *foldersize(struct stat st)
 250 {
 251     static char str[33], *p;
 252
 253     snprintf(str, sizeof(str), "%lu", (unsigned long) st.st_size);
 254     p = str;
 255     return p;
 256 }
 257
 258 /* This is output if the -h command line option is passed to the main program.
 259  */
 260 void ui_module_help()
 261 {
 262     printf("  Mail information [-M (-%s)]:\n", MAIL_OPTION_ORDER);
 263     printf("\t-f  forwarding addresses\t");
 264     printf("-a  mail aliases\n");
 265     printf("\t-r  folder access (read) time\t");
 266     printf("-m  folder modification time\n");
 267     printf("\t-s  folder size\n\n");
 268 }
 269
 270 /* This is the equivalent to main() only without argc and argv available. */
 271 int ui_module_exec(char ***s, const struct passwd *pw, const int multi_char,
 272               const int verbose, char *tf)
 273 {
 274     char *p = options;
 275     int gotstat = 0;
 276     struct stat st;
 277     char folder[PATH_MAX];
 278
 279     strings = *s;
 280     folder[0] = '\0';
 281     snprintf(folder, sizeof(folder), "%s/%s", _PATH_MAILDIR, pw->pw_name);
 282
 283     if (stat(folder, &st) != -1)
 284         gotstat = 1;
 285
 286     for (; *p; p++) {
 287         switch (*p) {
 288             case 's':
 289                 add_string(&strings, (gotstat) ? foldersize(st) : "!");
 290                 break;
 291             case 'r':
 292                 add_string(&strings, (gotstat) ? stamp(st.st_atime, tf) : "!");
 293                 break;
 294             case 'm':
 295                 add_string(&strings, (gotstat) ? stamp(st.st_mtime, tf) : "!");
 296                 break;
 297             case 'f':
 298                 add_string(&strings, forwards(pw->pw_dir, multi_char));
 299                 break;
 300             case 'a':
 301                 add_string(&strings, mail_aliases(pw->pw_name, multi_char));
 302                 break;
 303             default:
 304                 break;
 305         }
 306     }
 307
 308     *s = strings;
 309     return EXIT_SUCCESS;
 310 }
 311
 312 char *ui_module_options_init(char **defaults)
 313 {
 314     *defaults = "M";
 315     return MAIL_OPTION_STRING;
 316 }
 317
 318 /* Check module option validity. */
 319 int ui_module_options(int argc, char **argv)
 320 {
 321     int opt;
 322     char *p = options;
 323
 324     while ((opt = getopt(argc, argv, MAIL_OPTION_STRING)) != -1) {
 325         switch (opt) {
 326             case 'M':
 327                 strncpy(options, MAIL_OPTION_ORDER, sizeof(options));
 328                 return 0;
 329             case 'f':
 330             case 's':
 331             case 'r':
 332             case 'm':
 333             case 'a':
 334                 break;
 335             case '?':
 336                 warnx("mail: invalid option -- %c", optopt);
 337             default:
 338                 return 1;
 339         }
 340
 341         *p++ = opt;
 342         *p = '\0';
 343     }
 344
 345     return 0;
 346 }