diplodocus.org Git - nmh/blob - uip/aliasbr.c

   1
   2 /*
   3  * aliasbr.c -- new aliasing mechanism
   4  *
   5  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   6  * COPYRIGHT file in the root directory of the nmh distribution for
   7  * complete copyright information.
   8  */
   9
  10 #include <h/mh.h>
  11 #include <h/aliasbr.h>
  12 #include <h/addrsbr.h>
  13 #include <h/utils.h>
  14 #include <grp.h>
  15 #include <pwd.h>
  16
  17 static int akvis;
  18 static char *akerrst;
  19
  20 struct aka *akahead = NULL;
  21 struct aka *akatail = NULL;
  22
  23 struct home *homehead = NULL;
  24 struct home *hometail = NULL;
  25
  26 /*
  27  * prototypes
  28  */
  29 int alias (char *);
  30 int akvisible (void);
  31 void init_pw (void);
  32 char *akresult (struct aka *);
  33 char *akvalue (char *);
  34 char *akerror (int);
  35
  36 static  char *akval (struct aka *, char *);
  37 static int aleq (char *, char *);
  38 static char *scanp (char *);
  39 static char *getp (char *);
  40 static char *seekp (char *, char *, char **);
  41 static int addfile (struct aka *, char *);
  42 static int addgroup (struct aka *, char *);
  43 static int addmember (struct aka *, char *);
  44 static char *getalias (char *);
  45 static void add_aka (struct aka *, char *);
  46 static struct aka *akalloc (char *);
  47 static struct home *hmalloc (struct passwd *);
  48
  49
  50 /* Do mh alias substitution on 's' and return the results. */
  51 char *
  52 akvalue (char *s)
  53 {
  54     register char *v;
  55
  56     if (akahead == NULL)
  57         alias (AliasFile);
  58
  59     akvis = -1;
  60     v = akval (akahead, s);
  61     if (akvis == -1)
  62         akvis = 0;
  63     return v;
  64 }
  65
  66
  67 int
  68 akvisible (void)
  69 {
  70     return akvis;
  71 }
  72
  73
  74 char *
  75 akresult (struct aka *ak)
  76 {
  77     register char *cp = NULL, *dp, *pp;
  78     register struct adr *ad;
  79
  80     for (ad = ak->ak_addr; ad; ad = ad->ad_next) {
  81         pp = ad->ad_local ? akval (ak->ak_next, ad->ad_text)
  82             : getcpy (ad->ad_text);
  83
  84         if (cp) {
  85             dp = cp;
  86             cp = concat (cp, ",", pp, NULL);
  87             free (dp);
  88             free (pp);
  89         }
  90         else
  91             cp = pp;
  92     }
  93
  94     if (akvis == -1)
  95         akvis = ak->ak_visible;
  96     return cp;
  97 }
  98
  99
 100 static  char *
 101 akval (struct aka *ak, char *s)
 102 {
 103     if (!s)
 104         return s;                       /* XXX */
 105
 106     /* It'd be tempting to check for a trailing semicolon and remove
 107        it.  But that would break the EXMH alias parser on what would
 108        then be valid expressions:
 109        http://lists.gnu.org/archive/html/nmh-workers/2012-10/msg00039.html
 110      */
 111
 112     for (; ak; ak = ak->ak_next) {
 113         if (aleq (s, ak->ak_name)) {
 114             return akresult (ak);
 115         } else if (strchr (s, ':')) {
 116             /* The first address in a blind list will contain the
 117                alias name, so try to match, but just with just the
 118                address (not including the list name).  If there's a
 119                match, then replace the alias part with its
 120                expansion. */
 121
 122             char *name = getname (s);
 123             char *cp = NULL;
 124
 125             if (name) {
 126                 /* s is of the form "Blind list: address".  If address
 127                    is an alias, expand it. */
 128                 struct mailname *mp = getm (name, NULL, 0, NULL, 0);
 129
 130                 if (mp  &&  mp->m_ingrp) {
 131                     char *gname = add (mp->m_gname, NULL);
 132
 133                     if (gname  &&  aleq (name, ak->ak_name)) {
 134                         /* Will leak cp. */
 135                         cp = concat (gname, akresult (ak), NULL);
 136                         free (gname);
 137                     }
 138                 }
 139
 140                 mnfree (mp);
 141             }
 142
 143             /* Need to flush getname after use. */
 144             while (getname ("")) continue;
 145
 146             if (cp) {
 147                 return cp;
 148             }
 149         }
 150     }
 151
 152     return getcpy (s);
 153 }
 154
 155
 156 static int
 157 aleq (char *string, char *aliasent)
 158 {
 159     register char c;
 160
 161     while ((c = *string++))
 162         if (*aliasent == '*')
 163             return 1;
 164         else
 165             if ((c | 040) != (*aliasent | 040))
 166                 return 0;
 167             else
 168                 aliasent++;
 169
 170     return (*aliasent == 0 || *aliasent == '*');
 171 }
 172
 173
 174 int
 175 alias (char *file)
 176 {
 177     int i;
 178     register char *bp, *cp, *pp;
 179     char lc, *ap;
 180     register struct aka *ak = NULL;
 181     register FILE *fp;
 182
 183     if (*file != '/'
 184             && (strncmp (file, "./", 2) && strncmp (file, "../", 3)))
 185         file = etcpath (file);
 186     if ((fp = fopen (file, "r")) == NULL) {
 187         akerrst = file;
 188         return AK_NOFILE;
 189     }
 190
 191     while (vfgets (fp, &ap) == OK) {
 192         bp = ap;
 193         switch (*(pp = scanp (bp))) {
 194             case '<':           /* recurse a level */
 195                 if (!*(cp = getp (pp + 1))) {
 196                     akerrst = "'<' without alias-file";
 197                     fclose (fp);
 198                     return AK_ERROR;
 199                 }
 200                 if ((i = alias (cp)) != AK_OK) {
 201                     fclose (fp);
 202                     return i;
 203                 }
 204
 205             case ':':           /* comment */
 206             case ';':
 207             case '#':
 208             case 0:
 209                 continue;
 210         }
 211
 212         akerrst = bp;
 213         if (!*(cp = seekp (pp, &lc, &ap))) {
 214             fclose (fp);
 215             return AK_ERROR;
 216         }
 217         if (!(ak = akalloc (cp))) {
 218             fclose (fp);
 219             return AK_LIMIT;
 220         }
 221         switch (lc) {
 222             case ':':
 223                 ak->ak_visible = 0;
 224                 break;
 225
 226             case ';':
 227                 ak->ak_visible = 1;
 228                 break;
 229
 230             default:
 231                 fclose (fp);
 232                 return AK_ERROR;
 233         }
 234
 235         switch (*(pp = scanp (ap))) {
 236             case 0:             /* EOL */
 237                 fclose (fp);
 238                 return AK_ERROR;
 239
 240             case '<':           /* read values from file */
 241                 if (!*(cp = getp (pp + 1))) {
 242                     fclose (fp);
 243                     return AK_ERROR;
 244                 }
 245                 if (!addfile (ak, cp)) {
 246                     fclose (fp);
 247                     return AK_NOFILE;
 248                 }
 249                 break;
 250
 251             case '=':           /* UNIX group */
 252                 if (!*(cp = getp (pp + 1))) {
 253                     fclose (fp);
 254                     return AK_ERROR;
 255                 }
 256                 if (!addgroup (ak, cp)) {
 257                     fclose (fp);
 258                     return AK_NOGROUP;
 259                 }
 260                 break;
 261
 262             case '+':           /* UNIX group members */
 263                 if (!*(cp = getp (pp + 1))) {
 264                     fclose (fp);
 265                     return AK_ERROR;
 266                 }
 267                 if (!addmember (ak, cp)) {
 268                     fclose (fp);
 269                     return AK_NOGROUP;
 270                 }
 271                 break;
 272
 273             default:            /* list */
 274                 while ((cp = getalias (pp)))
 275                     add_aka (ak, cp);
 276                 break;
 277         }
 278     }
 279
 280     fclose (fp);
 281     return AK_OK;
 282 }
 283
 284
 285 char *
 286 akerror (int i)
 287 {
 288     static char buffer[BUFSIZ];
 289
 290     switch (i) {
 291         case AK_NOFILE:
 292             snprintf (buffer, sizeof(buffer), "unable to read '%s'", akerrst);
 293             break;
 294
 295         case AK_ERROR:
 296             snprintf (buffer, sizeof(buffer), "error in line '%s'", akerrst);
 297             break;
 298
 299         case AK_LIMIT:
 300             snprintf (buffer, sizeof(buffer), "out of memory while on '%s'", akerrst);
 301             break;
 302
 303         case AK_NOGROUP:
 304             snprintf (buffer, sizeof(buffer), "no such group as '%s'", akerrst);
 305             break;
 306
 307         default:
 308             snprintf (buffer, sizeof(buffer), "unknown error (%d)", i);
 309             break;
 310     }
 311
 312     return buffer;
 313 }
 314
 315
 316 static char *
 317 scanp (char *p)
 318 {
 319     while (isspace ((unsigned char) *p))
 320         p++;
 321     return p;
 322 }
 323
 324
 325 static char *
 326 getp (char *p)
 327 {
 328     char  *cp = scanp (p);
 329
 330     p = cp;
 331     while (!isspace ((unsigned char) *cp) && *cp)
 332         cp++;
 333     *cp = 0;
 334
 335     return p;
 336 }
 337
 338
 339 static char *
 340 seekp (char *p, char *c, char **a)
 341 {
 342     char *cp;
 343
 344     p = cp = scanp (p);
 345     while (!isspace ((unsigned char) *cp) && *cp && *cp != ':' && *cp != ';')
 346         cp++;
 347     *c = *cp;
 348     *cp++ = 0;
 349     *a = cp;
 350
 351     return p;
 352 }
 353
 354
 355 static int
 356 addfile (struct aka *ak, char *file)
 357 {
 358     register char *cp;
 359     char buffer[BUFSIZ];
 360     register FILE *fp;
 361
 362     if (!(fp = fopen (etcpath (file), "r"))) {
 363         akerrst = file;
 364         return 0;
 365     }
 366
 367     while (fgets (buffer, sizeof buffer, fp))
 368         while ((cp = getalias (buffer)))
 369             add_aka (ak, cp);
 370
 371     fclose (fp);
 372     return 1;
 373 }
 374
 375
 376 static int
 377 addgroup (struct aka *ak, char *grp)
 378 {
 379     register char *gp;
 380     register struct group *gr = getgrnam (grp);
 381     register struct home *hm = NULL;
 382
 383     if (!gr)
 384         gr = getgrgid (atoi (grp));
 385     if (!gr) {
 386         akerrst = grp;
 387         return 0;
 388     }
 389
 390     while ((gp = *gr->gr_mem++))
 391     {
 392         struct passwd *pw;
 393         for (hm = homehead; hm; hm = hm->h_next)
 394             if (!strcmp (hm->h_name, gp)) {
 395                 add_aka (ak, hm->h_name);
 396                 break;
 397             }
 398         if ((pw = getpwnam(gp)))
 399         {
 400                 hmalloc(pw);
 401                 add_aka (ak, gp);
 402         }
 403     }
 404
 405     return 1;
 406 }
 407
 408
 409 static int
 410 addmember (struct aka *ak, char *grp)
 411 {
 412     gid_t gid;
 413     register struct group *gr = getgrnam (grp);
 414     register struct home *hm = NULL;
 415
 416     if (gr)
 417         gid = gr->gr_gid;
 418     else {
 419         gid = atoi (grp);
 420         gr = getgrgid (gid);
 421     }
 422     if (!gr) {
 423         akerrst = grp;
 424         return 0;
 425     }
 426
 427     init_pw ();
 428
 429     for (hm = homehead; hm; hm = hm->h_next)
 430         if (hm->h_gid == gid)
 431             add_aka (ak, hm->h_name);
 432
 433     return 1;
 434 }
 435
 436
 437 static char *
 438 getalias (char *addrs)
 439 {
 440     char *pp, *qp;
 441     static char *cp = NULL;
 442
 443     if (cp == NULL)
 444         cp = addrs;
 445     else
 446         if (*cp == 0)
 447             return (cp = NULL);
 448
 449     /* Remove leading any space from the address. */
 450     for (pp = cp; isspace ((unsigned char) *pp); pp++)
 451         continue;
 452     if (*pp == 0)
 453         return (cp = NULL);
 454     /* Find the end of the address. */
 455     for (qp = pp; *qp != 0 && *qp != ','; qp++)
 456         continue;
 457     /* Set cp to point to the remainder of the addresses. */
 458     if (*qp == ',')
 459         *qp++ = 0;
 460     for (cp = qp, qp--; qp > pp; qp--)
 461         if (*qp != 0) {
 462             if (isspace ((unsigned char) *qp))
 463                 *qp = 0;
 464             else
 465                 break;
 466         }
 467
 468     return pp;
 469 }
 470
 471
 472 static void
 473 add_aka (struct aka *ak, char *pp)
 474 {
 475     register struct adr *ad, *ld;
 476
 477     for (ad = ak->ak_addr, ld = NULL; ad; ld = ad, ad = ad->ad_next)
 478         if (!strcmp (pp, ad->ad_text))
 479             return;
 480
 481     ad = (struct adr *) mh_xmalloc (sizeof(*ad));
 482     ad->ad_text = getcpy (pp);
 483     ad->ad_local = strchr(pp, '@') == NULL && strchr(pp, '!') == NULL;
 484     ad->ad_next = NULL;
 485     if (ak->ak_addr)
 486         ld->ad_next = ad;
 487     else
 488         ak->ak_addr = ad;
 489 }
 490
 491
 492 void
 493 init_pw (void)
 494 {
 495     register struct passwd  *pw;
 496     static int init;
 497
 498     if (!init)
 499     {
 500         /* if the list has yet to be initialized */
 501         /* zap the list, and rebuild from scratch */
 502         homehead=NULL;
 503         hometail=NULL;
 504         init++;
 505
 506         setpwent ();
 507
 508         while ((pw = getpwent ()))
 509             if (!hmalloc (pw))
 510                 break;
 511
 512         endpwent ();
 513     }
 514 }
 515
 516
 517 static struct aka *
 518 akalloc (char *id)
 519 {
 520     register struct aka *p;
 521
 522     p = (struct aka *) mh_xmalloc (sizeof(*p));
 523
 524     p->ak_name = getcpy (id);
 525     p->ak_visible = 0;
 526     p->ak_addr = NULL;
 527     p->ak_next = NULL;
 528     if (akatail != NULL)
 529         akatail->ak_next = p;
 530     if (akahead == NULL)
 531         akahead = p;
 532     akatail = p;
 533
 534     return p;
 535 }
 536
 537
 538 static struct home *
 539 hmalloc (struct passwd *pw)
 540 {
 541     register struct home *p;
 542
 543     p = (struct home *) mh_xmalloc (sizeof(*p));
 544
 545     p->h_name = getcpy (pw->pw_name);
 546     p->h_uid = pw->pw_uid;
 547     p->h_gid = pw->pw_gid;
 548     p->h_home = getcpy (pw->pw_dir);
 549     p->h_shell = getcpy (pw->pw_shell);
 550     p->h_ngrps = 0;
 551     p->h_next = NULL;
 552     if (hometail != NULL)
 553         hometail->h_next = p;
 554     if (homehead == NULL)
 555         homehead = p;
 556     hometail = p;
 557
 558     return p;
 559 }