exclude.c

   1 /*
   2  * The filter include/exclude routines.
   3  *
   4  * Copyright (C) 1996-2001 Andrew Tridgell <tridge@samba.org>
   5  * Copyright (C) 1996 Paul Mackerras
   6  * Copyright (C) 2002 Martin Pool
   7  * Copyright (C) 2003-2020 Wayne Davison
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 3 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, visit the http://fsf.org website.
  21  */
  22
  23 #include "rsync.h"
  24 #include "default-cvsignore.h"
  25 #include "ifuncs.h"
  26
  27 extern int am_server;
  28 extern int am_sender;
  29 extern int eol_nulls;
  30 extern int io_error;
  31 extern int local_server;
  32 extern int prune_empty_dirs;
  33 extern int ignore_perishable;
  34 extern int delete_mode;
  35 extern int delete_excluded;
  36 extern int cvs_exclude;
  37 extern int sanitize_paths;
  38 extern int protocol_version;
  39 extern int module_id;
  40
  41 extern char curr_dir[MAXPATHLEN];
  42 extern unsigned int curr_dir_len;
  43 extern unsigned int module_dirlen;
  44
  45 filter_rule_list filter_list = { .debug_type = "" };
  46 filter_rule_list cvs_filter_list = { .debug_type = " [global CVS]" };
  47 filter_rule_list daemon_filter_list = { .debug_type = " [daemon]" };
  48
  49 int saw_xattr_filter = 0;
  50
  51 /* Need room enough for ":MODS " prefix plus some room to grow. */
  52 #define MAX_RULE_PREFIX (16)
  53
  54 #define SLASH_WILD3_SUFFIX "/***"
  55
  56 /* The dirbuf is set by push_local_filters() to the current subdirectory
  57  * relative to curr_dir that is being processed.  The path always has a
  58  * trailing slash appended, and the variable dirbuf_len contains the length
  59  * of this path prefix.  The path is always absolute. */
  60 static char dirbuf[MAXPATHLEN+1];
  61 static unsigned int dirbuf_len = 0;
  62 static int dirbuf_depth;
  63
  64 /* This is True when we're scanning parent dirs for per-dir merge-files. */
  65 static BOOL parent_dirscan = False;
  66
  67 /* This array contains a list of all the currently active per-dir merge
  68  * files.  This makes it easier to save the appropriate values when we
  69  * "push" down into each subdirectory. */
  70 static filter_rule **mergelist_parents;
  71 static int mergelist_cnt = 0;
  72 static int mergelist_size = 0;
  73
  74 /* Each filter_list_struct describes a singly-linked list by keeping track
  75  * of both the head and tail pointers.  The list is slightly unusual in that
  76  * a parent-dir's content can be appended to the end of the local list in a
  77  * special way:  the last item in the local list has its "next" pointer set
  78  * to point to the inherited list, but the local list's tail pointer points
  79  * at the end of the local list.  Thus, if the local list is empty, the head
  80  * will be pointing at the inherited content but the tail will be NULL.  To
  81  * help you visualize this, here are the possible list arrangements:
  82  *
  83  * Completely Empty                     Local Content Only
  84  * ==================================   ====================================
  85  * head -> NULL                         head -> Local1 -> Local2 -> NULL
  86  * tail -> NULL                         tail -------------^
  87  *
  88  * Inherited Content Only               Both Local and Inherited Content
  89  * ==================================   ====================================
  90  * head -> Parent1 -> Parent2 -> NULL   head -> L1 -> L2 -> P1 -> P2 -> NULL
  91  * tail -> NULL                         tail ---------^
  92  *
  93  * This means that anyone wanting to traverse the whole list to use it just
  94  * needs to start at the head and use the "next" pointers until it goes
  95  * NULL.  To add new local content, we insert the item after the tail item
  96  * and update the tail (obviously, if "tail" was NULL, we insert it at the
  97  * head).  To clear the local list, WE MUST NOT FREE THE INHERITED CONTENT
  98  * because it is shared between the current list and our parent list(s).
  99  * The easiest way to handle this is to simply truncate the list after the
 100  * tail item and then free the local list from the head.  When inheriting
 101  * the list for a new local dir, we just save off the filter_list_struct
 102  * values (so we can pop back to them later) and set the tail to NULL.
 103  */
 104
 105 static void teardown_mergelist(filter_rule *ex)
 106 {
 107         int j;
 108
 109         if (!ex->u.mergelist)
 110                 return;
 111
 112         if (DEBUG_GTE(FILTER, 2)) {
 113                 rprintf(FINFO, "[%s] deactivating mergelist #%d%s\n",
 114                         who_am_i(), mergelist_cnt - 1,
 115                         ex->u.mergelist->debug_type);
 116         }
 117
 118         free(ex->u.mergelist->debug_type);
 119         free(ex->u.mergelist);
 120
 121         for (j = 0; j < mergelist_cnt; j++) {
 122                 if (mergelist_parents[j] == ex) {
 123                         mergelist_parents[j] = NULL;
 124                         break;
 125                 }
 126         }
 127         while (mergelist_cnt && mergelist_parents[mergelist_cnt-1] == NULL)
 128                 mergelist_cnt--;
 129 }
 130
 131 static void free_filter(filter_rule *ex)
 132 {
 133         if (ex->rflags & FILTRULE_PERDIR_MERGE)
 134                 teardown_mergelist(ex);
 135         free(ex->pattern);
 136         free(ex);
 137 }
 138
 139 static void free_filters(filter_rule *ent)
 140 {
 141         while (ent) {
 142                 filter_rule *next = ent->next;
 143                 free_filter(ent);
 144                 ent = next;
 145         }
 146 }
 147
 148 /* Build a filter structure given a filter pattern.  The value in "pat"
 149  * is not null-terminated.  "rule" is either held or freed, so the
 150  * caller should not free it. */
 151 static void add_rule(filter_rule_list *listp, const char *pat, unsigned int pat_len,
 152                      filter_rule *rule, int xflags)
 153 {
 154         const char *cp;
 155         unsigned int pre_len, suf_len, slash_cnt = 0;
 156
 157         if (DEBUG_GTE(FILTER, 2)) {
 158                 rprintf(FINFO, "[%s] add_rule(%s%.*s%s)%s\n",
 159                         who_am_i(), get_rule_prefix(rule, pat, 0, NULL),
 160                         (int)pat_len, pat,
 161                         (rule->rflags & FILTRULE_DIRECTORY) ? "/" : "",
 162                         listp->debug_type);
 163         }
 164
 165         /* These flags also indicate that we're reading a list that
 166          * needs to be filtered now, not post-filtered later. */
 167         if (xflags & (XFLG_ANCHORED2ABS|XFLG_ABS_IF_SLASH)
 168                 && (rule->rflags & FILTRULES_SIDES)
 169                         == (am_sender ? FILTRULE_RECEIVER_SIDE : FILTRULE_SENDER_SIDE)) {
 170                 /* This filter applies only to the other side.  Drop it. */
 171                 free_filter(rule);
 172                 return;
 173         }
 174
 175         if (pat_len > 1 && pat[pat_len-1] == '/') {
 176                 pat_len--;
 177                 rule->rflags |= FILTRULE_DIRECTORY;
 178         }
 179
 180         for (cp = pat; cp < pat + pat_len; cp++) {
 181                 if (*cp == '/')
 182                         slash_cnt++;
 183         }
 184
 185         if (!(rule->rflags & (FILTRULE_ABS_PATH | FILTRULE_MERGE_FILE))
 186          && ((xflags & (XFLG_ANCHORED2ABS|XFLG_ABS_IF_SLASH) && *pat == '/')
 187           || (xflags & XFLG_ABS_IF_SLASH && slash_cnt))) {
 188                 rule->rflags |= FILTRULE_ABS_PATH;
 189                 if (*pat == '/')
 190                         pre_len = dirbuf_len - module_dirlen - 1;
 191                 else
 192                         pre_len = 0;
 193         } else
 194                 pre_len = 0;
 195
 196         /* The daemon wants dir-exclude rules to get an appended "/" + "***". */
 197         if (xflags & XFLG_DIR2WILD3
 198          && BITS_SETnUNSET(rule->rflags, FILTRULE_DIRECTORY, FILTRULE_INCLUDE)) {
 199                 rule->rflags &= ~FILTRULE_DIRECTORY;
 200                 suf_len = sizeof SLASH_WILD3_SUFFIX - 1;
 201         } else
 202                 suf_len = 0;
 203
 204         rule->pattern = new_array(char, pre_len + pat_len + suf_len + 1);
 205         if (pre_len) {
 206                 memcpy(rule->pattern, dirbuf + module_dirlen, pre_len);
 207                 for (cp = rule->pattern; cp < rule->pattern + pre_len; cp++) {
 208                         if (*cp == '/')
 209                                 slash_cnt++;
 210                 }
 211         }
 212         strlcpy(rule->pattern + pre_len, pat, pat_len + 1);
 213         pat_len += pre_len;
 214         if (suf_len) {
 215                 memcpy(rule->pattern + pat_len, SLASH_WILD3_SUFFIX, suf_len+1);
 216                 pat_len += suf_len;
 217                 slash_cnt++;
 218         }
 219
 220         if (strpbrk(rule->pattern, "*[?")) {
 221                 rule->rflags |= FILTRULE_WILD;
 222                 if ((cp = strstr(rule->pattern, "**")) != NULL) {
 223                         rule->rflags |= FILTRULE_WILD2;
 224                         /* If the pattern starts with **, note that. */
 225                         if (cp == rule->pattern)
 226                                 rule->rflags |= FILTRULE_WILD2_PREFIX;
 227                         /* If the pattern ends with ***, note that. */
 228                         if (pat_len >= 3
 229                          && rule->pattern[pat_len-3] == '*'
 230                          && rule->pattern[pat_len-2] == '*'
 231                          && rule->pattern[pat_len-1] == '*')
 232                                 rule->rflags |= FILTRULE_WILD3_SUFFIX;
 233                 }
 234         }
 235
 236         if (rule->rflags & FILTRULE_PERDIR_MERGE) {
 237                 filter_rule_list *lp;
 238                 unsigned int len;
 239                 int i;
 240
 241                 if ((cp = strrchr(rule->pattern, '/')) != NULL)
 242                         cp++;
 243                 else
 244                         cp = rule->pattern;
 245
 246                 /* If the local merge file was already mentioned, don't
 247                  * add it again. */
 248                 for (i = 0; i < mergelist_cnt; i++) {
 249                         filter_rule *ex = mergelist_parents[i];
 250                         const char *s;
 251                         if (!ex)
 252                                 continue;
 253                         s = strrchr(ex->pattern, '/');
 254                         if (s)
 255                                 s++;
 256                         else
 257                                 s = ex->pattern;
 258                         len = strlen(s);
 259                         if (len == pat_len - (cp - rule->pattern) && memcmp(s, cp, len) == 0) {
 260                                 free_filter(rule);
 261                                 return;
 262                         }
 263                 }
 264
 265                 lp = new_array0(filter_rule_list, 1);
 266                 if (asprintf(&lp->debug_type, " [per-dir %s]", cp) < 0)
 267                         out_of_memory("add_rule");
 268                 rule->u.mergelist = lp;
 269
 270                 if (mergelist_cnt == mergelist_size) {
 271                         mergelist_size += 5;
 272                         mergelist_parents = realloc_array(mergelist_parents, filter_rule *, mergelist_size);
 273                 }
 274                 if (DEBUG_GTE(FILTER, 2)) {
 275                         rprintf(FINFO, "[%s] activating mergelist #%d%s\n",
 276                                 who_am_i(), mergelist_cnt, lp->debug_type);
 277                 }
 278                 mergelist_parents[mergelist_cnt++] = rule;
 279         } else
 280                 rule->u.slash_cnt = slash_cnt;
 281
 282         if (!listp->tail) {
 283                 rule->next = listp->head;
 284                 listp->head = listp->tail = rule;
 285         } else {
 286                 rule->next = listp->tail->next;
 287                 listp->tail->next = rule;
 288                 listp->tail = rule;
 289         }
 290 }
 291
 292 /* This frees any non-inherited items, leaving just inherited items on the list. */
 293 static void pop_filter_list(filter_rule_list *listp)
 294 {
 295         filter_rule *inherited;
 296
 297         if (!listp->tail)
 298                 return;
 299
 300         inherited = listp->tail->next;
 301
 302         /* Truncate any inherited items from the local list. */
 303         listp->tail->next = NULL;
 304         /* Now free everything that is left. */
 305         free_filters(listp->head);
 306
 307         listp->head = inherited;
 308         listp->tail = NULL;
 309 }
 310
 311 /* This returns an expanded (absolute) filename for the merge-file name if
 312  * the name has any slashes in it OR if the parent_dirscan var is True;
 313  * otherwise it returns the original merge_file name.  If the len_ptr value
 314  * is non-NULL the merge_file name is limited by the referenced length
 315  * value and will be updated with the length of the resulting name.  We
 316  * always return a name that is null terminated, even if the merge_file
 317  * name was not. */
 318 static char *parse_merge_name(const char *merge_file, unsigned int *len_ptr,
 319                               unsigned int prefix_skip)
 320 {
 321         static char buf[MAXPATHLEN];
 322         char *fn, tmpbuf[MAXPATHLEN];
 323         unsigned int fn_len;
 324
 325         if (!parent_dirscan && *merge_file != '/') {
 326                 /* Return the name unchanged it doesn't have any slashes. */
 327                 if (len_ptr) {
 328                         const char *p = merge_file + *len_ptr;
 329                         while (--p > merge_file && *p != '/') {}
 330                         if (p == merge_file) {
 331                                 strlcpy(buf, merge_file, *len_ptr + 1);
 332                                 return buf;
 333                         }
 334                 } else if (strchr(merge_file, '/') == NULL)
 335                         return (char *)merge_file;
 336         }
 337
 338         fn = *merge_file == '/' ? buf : tmpbuf;
 339         if (sanitize_paths) {
 340                 const char *r = prefix_skip ? "/" : NULL;
 341                 /* null-terminate the name if it isn't already */
 342                 if (len_ptr && merge_file[*len_ptr]) {
 343                         char *to = fn == buf ? tmpbuf : buf;
 344                         strlcpy(to, merge_file, *len_ptr + 1);
 345                         merge_file = to;
 346                 }
 347                 if (!sanitize_path(fn, merge_file, r, dirbuf_depth, SP_DEFAULT)) {
 348                         rprintf(FERROR, "merge-file name overflows: %s\n",
 349                                 merge_file);
 350                         return NULL;
 351                 }
 352                 fn_len = strlen(fn);
 353         } else {
 354                 strlcpy(fn, merge_file, len_ptr ? *len_ptr + 1 : MAXPATHLEN);
 355                 fn_len = clean_fname(fn, CFN_COLLAPSE_DOT_DOT_DIRS);
 356         }
 357
 358         /* If the name isn't in buf yet, it wasn't absolute. */
 359         if (fn != buf) {
 360                 int d_len = dirbuf_len - prefix_skip;
 361                 if (d_len + fn_len >= MAXPATHLEN) {
 362                         rprintf(FERROR, "merge-file name overflows: %s\n", fn);
 363                         return NULL;
 364                 }
 365                 memcpy(buf, dirbuf + prefix_skip, d_len);
 366                 memcpy(buf + d_len, fn, fn_len + 1);
 367                 fn_len = clean_fname(buf, CFN_COLLAPSE_DOT_DOT_DIRS);
 368         }
 369
 370         if (len_ptr)
 371                 *len_ptr = fn_len;
 372         return buf;
 373 }
 374
 375 /* Sets the dirbuf and dirbuf_len values. */
 376 void set_filter_dir(const char *dir, unsigned int dirlen)
 377 {
 378         unsigned int len;
 379         if (*dir != '/') {
 380                 memcpy(dirbuf, curr_dir, curr_dir_len);
 381                 dirbuf[curr_dir_len] = '/';
 382                 len = curr_dir_len + 1;
 383                 if (len + dirlen >= MAXPATHLEN)
 384                         dirlen = 0;
 385         } else
 386                 len = 0;
 387         memcpy(dirbuf + len, dir, dirlen);
 388         dirbuf[dirlen + len] = '\0';
 389         dirbuf_len = clean_fname(dirbuf, CFN_COLLAPSE_DOT_DOT_DIRS);
 390         if (dirbuf_len > 1 && dirbuf[dirbuf_len-1] == '.'
 391             && dirbuf[dirbuf_len-2] == '/')
 392                 dirbuf_len -= 2;
 393         if (dirbuf_len != 1)
 394                 dirbuf[dirbuf_len++] = '/';
 395         dirbuf[dirbuf_len] = '\0';
 396         if (sanitize_paths)
 397                 dirbuf_depth = count_dir_elements(dirbuf + module_dirlen);
 398 }
 399
 400 /* This routine takes a per-dir merge-file entry and finishes its setup.
 401  * If the name has a path portion then we check to see if it refers to a
 402  * parent directory of the first transfer dir.  If it does, we scan all the
 403  * dirs from that point through the parent dir of the transfer dir looking
 404  * for the per-dir merge-file in each one. */
 405 static BOOL setup_merge_file(int mergelist_num, filter_rule *ex,
 406                              filter_rule_list *lp)
 407 {
 408         char buf[MAXPATHLEN];
 409         char *x, *y, *pat = ex->pattern;
 410         unsigned int len;
 411
 412         if (!(x = parse_merge_name(pat, NULL, 0)) || *x != '/')
 413                 return 0;
 414
 415         if (DEBUG_GTE(FILTER, 2)) {
 416                 rprintf(FINFO, "[%s] performing parent_dirscan for mergelist #%d%s\n",
 417                         who_am_i(), mergelist_num, lp->debug_type);
 418         }
 419         y = strrchr(x, '/');
 420         *y = '\0';
 421         ex->pattern = strdup(y+1);
 422         if (!*x)
 423                 x = "/";
 424         if (*x == '/')
 425                 strlcpy(buf, x, MAXPATHLEN);
 426         else
 427                 pathjoin(buf, MAXPATHLEN, dirbuf, x);
 428
 429         len = clean_fname(buf, CFN_COLLAPSE_DOT_DOT_DIRS);
 430         if (len != 1 && len < MAXPATHLEN-1) {
 431                 buf[len++] = '/';
 432                 buf[len] = '\0';
 433         }
 434         /* This ensures that the specified dir is a parent of the transfer. */
 435         for (x = buf, y = dirbuf; *x && *x == *y; x++, y++) {}
 436         if (*x)
 437                 y += strlen(y); /* nope -- skip the scan */
 438
 439         parent_dirscan = True;
 440         while (*y) {
 441                 char save[MAXPATHLEN];
 442                 strlcpy(save, y, MAXPATHLEN);
 443                 *y = '\0';
 444                 dirbuf_len = y - dirbuf;
 445                 strlcpy(x, ex->pattern, MAXPATHLEN - (x - buf));
 446                 parse_filter_file(lp, buf, ex, XFLG_ANCHORED2ABS);
 447                 if (ex->rflags & FILTRULE_NO_INHERIT) {
 448                         /* Free the undesired rules to clean up any per-dir
 449                          * mergelists they defined.  Otherwise pop_local_filters
 450                          * may crash trying to restore nonexistent state for
 451                          * those mergelists. */
 452                         free_filters(lp->head);
 453                         lp->head = NULL;
 454                 }
 455                 lp->tail = NULL;
 456                 strlcpy(y, save, MAXPATHLEN);
 457                 while ((*x++ = *y++) != '/') {}
 458         }
 459         parent_dirscan = False;
 460         if (DEBUG_GTE(FILTER, 2)) {
 461                 rprintf(FINFO, "[%s] completed parent_dirscan for mergelist #%d%s\n",
 462                         who_am_i(), mergelist_num, lp->debug_type);
 463         }
 464         free(pat);
 465         return 1;
 466 }
 467
 468 struct local_filter_state {
 469         int mergelist_cnt;
 470         filter_rule_list mergelists[1];
 471 };
 472
 473 /* Each time rsync changes to a new directory it call this function to
 474  * handle all the per-dir merge-files.  The "dir" value is the current path
 475  * relative to curr_dir (which might not be null-terminated).  We copy it
 476  * into dirbuf so that we can easily append a file name on the end. */
 477 void *push_local_filters(const char *dir, unsigned int dirlen)
 478 {
 479         struct local_filter_state *push;
 480         int i;
 481
 482         set_filter_dir(dir, dirlen);
 483         if (DEBUG_GTE(FILTER, 2)) {
 484                 rprintf(FINFO, "[%s] pushing local filters for %s\n",
 485                         who_am_i(), dirbuf);
 486         }
 487
 488         if (!mergelist_cnt) {
 489                 /* No old state to save and no new merge files to push. */
 490                 return NULL;
 491         }
 492
 493         push = (struct local_filter_state *)new_array(char,
 494                           sizeof (struct local_filter_state)
 495                         + (mergelist_cnt-1) * sizeof (filter_rule_list));
 496
 497         push->mergelist_cnt = mergelist_cnt;
 498         for (i = 0; i < mergelist_cnt; i++) {
 499                 filter_rule *ex = mergelist_parents[i];
 500                 if (!ex)
 501                         continue;
 502                 memcpy(&push->mergelists[i], ex->u.mergelist, sizeof (filter_rule_list));
 503         }
 504
 505         /* Note: parse_filter_file() might increase mergelist_cnt, so keep
 506          * this loop separate from the above loop. */
 507         for (i = 0; i < mergelist_cnt; i++) {
 508                 filter_rule *ex = mergelist_parents[i];
 509                 filter_rule_list *lp;
 510                 if (!ex)
 511                         continue;
 512                 lp = ex->u.mergelist;
 513
 514                 if (DEBUG_GTE(FILTER, 2)) {
 515                         rprintf(FINFO, "[%s] pushing mergelist #%d%s\n",
 516                                 who_am_i(), i, lp->debug_type);
 517                 }
 518
 519                 lp->tail = NULL; /* Switch any local rules to inherited. */
 520                 if (ex->rflags & FILTRULE_NO_INHERIT)
 521                         lp->head = NULL;
 522
 523                 if (ex->rflags & FILTRULE_FINISH_SETUP) {
 524                         ex->rflags &= ~FILTRULE_FINISH_SETUP;
 525                         if (setup_merge_file(i, ex, lp))
 526                                 set_filter_dir(dir, dirlen);
 527                 }
 528
 529                 if (strlcpy(dirbuf + dirbuf_len, ex->pattern,
 530                     MAXPATHLEN - dirbuf_len) < MAXPATHLEN - dirbuf_len) {
 531                         parse_filter_file(lp, dirbuf, ex,
 532                                           XFLG_ANCHORED2ABS);
 533                 } else {
 534                         io_error |= IOERR_GENERAL;
 535                         rprintf(FERROR,
 536                             "cannot add local filter rules in long-named directory: %s\n",
 537                             full_fname(dirbuf));
 538                 }
 539                 dirbuf[dirbuf_len] = '\0';
 540         }
 541
 542         return (void*)push;
 543 }
 544
 545 void pop_local_filters(void *mem)
 546 {
 547         struct local_filter_state *pop = (struct local_filter_state *)mem;
 548         int i;
 549         int old_mergelist_cnt = pop ? pop->mergelist_cnt : 0;
 550
 551         if (DEBUG_GTE(FILTER, 2))
 552                 rprintf(FINFO, "[%s] popping local filters\n", who_am_i());
 553
 554         for (i = mergelist_cnt; i-- > 0; ) {
 555                 filter_rule *ex = mergelist_parents[i];
 556                 filter_rule_list *lp;
 557                 if (!ex)
 558                         continue;
 559                 lp = ex->u.mergelist;
 560
 561                 if (DEBUG_GTE(FILTER, 2)) {
 562                         rprintf(FINFO, "[%s] popping mergelist #%d%s\n",
 563                                 who_am_i(), i, lp->debug_type);
 564                 }
 565
 566                 pop_filter_list(lp);
 567                 if (i >= old_mergelist_cnt && lp->head) {
 568                         /* This mergelist does not exist in the state to be restored, but it
 569                          * still has inherited rules.  This can sometimes happen if a per-dir
 570                          * merge file calls setup_merge_file() in push_local_filters() and that
 571                          * leaves some inherited rules that aren't in the pushed list state. */
 572                         if (DEBUG_GTE(FILTER, 2)) {
 573                                 rprintf(FINFO, "[%s] freeing parent_dirscan filters of mergelist #%d%s\n",
 574                                         who_am_i(), i, ex->u.mergelist->debug_type);
 575                         }
 576                         pop_filter_list(lp);
 577                 }
 578         }
 579
 580         if (!pop)
 581                 return; /* No state to restore. */
 582
 583         for (i = 0; i < old_mergelist_cnt; i++) {
 584                 filter_rule *ex = mergelist_parents[i];
 585                 if (!ex)
 586                         continue;
 587                 memcpy(ex->u.mergelist, &pop->mergelists[i], sizeof (filter_rule_list));
 588         }
 589
 590         free(pop);
 591 }
 592
 593 void change_local_filter_dir(const char *dname, int dlen, int dir_depth)
 594 {
 595         static int cur_depth = -1;
 596         static void *filt_array[MAXPATHLEN/2+1];
 597
 598         if (!dname) {
 599                 for ( ; cur_depth >= 0; cur_depth--) {
 600                         if (filt_array[cur_depth]) {
 601                                 pop_local_filters(filt_array[cur_depth]);
 602                                 filt_array[cur_depth] = NULL;
 603                         }
 604                 }
 605                 return;
 606         }
 607
 608         assert(dir_depth < MAXPATHLEN/2+1);
 609
 610         for ( ; cur_depth >= dir_depth; cur_depth--) {
 611                 if (filt_array[cur_depth]) {
 612                         pop_local_filters(filt_array[cur_depth]);
 613                         filt_array[cur_depth] = NULL;
 614                 }
 615         }
 616
 617         cur_depth = dir_depth;
 618         filt_array[cur_depth] = push_local_filters(dname, dlen);
 619 }
 620
 621 static int rule_matches(const char *fname, filter_rule *ex, int name_flags)
 622 {
 623         int slash_handling, str_cnt = 0, anchored_match = 0;
 624         int ret_match = ex->rflags & FILTRULE_NEGATE ? 0 : 1;
 625         char *p, *pattern = ex->pattern;
 626         const char *strings[16]; /* more than enough */
 627         const char *name = fname + (*fname == '/');
 628
 629         if (!*name)
 630                 return 0;
 631
 632         if (!(name_flags & NAME_IS_XATTR) ^ !(ex->rflags & FILTRULE_XATTR))
 633                 return 0;
 634
 635         if (!ex->u.slash_cnt && !(ex->rflags & FILTRULE_WILD2)) {
 636                 /* If the pattern does not have any slashes AND it does
 637                  * not have a "**" (which could match a slash), then we
 638                  * just match the name portion of the path. */
 639                 if ((p = strrchr(name,'/')) != NULL)
 640                         name = p+1;
 641         } else if (ex->rflags & FILTRULE_ABS_PATH && *fname != '/'
 642             && curr_dir_len > module_dirlen + 1) {
 643                 /* If we're matching against an absolute-path pattern,
 644                  * we need to prepend our full path info. */
 645                 strings[str_cnt++] = curr_dir + module_dirlen + 1;
 646                 strings[str_cnt++] = "/";
 647         } else if (ex->rflags & FILTRULE_WILD2_PREFIX && *fname != '/') {
 648                 /* Allow "**"+"/" to match at the start of the string. */
 649                 strings[str_cnt++] = "/";
 650         }
 651         strings[str_cnt++] = name;
 652         if (name_flags & NAME_IS_DIR) {
 653                 /* Allow a trailing "/"+"***" to match the directory. */
 654                 if (ex->rflags & FILTRULE_WILD3_SUFFIX)
 655                         strings[str_cnt++] = "/";
 656         } else if (ex->rflags & FILTRULE_DIRECTORY)
 657                 return !ret_match;
 658         strings[str_cnt] = NULL;
 659
 660         if (*pattern == '/') {
 661                 anchored_match = 1;
 662                 pattern++;
 663         }
 664
 665         if (!anchored_match && ex->u.slash_cnt
 666             && !(ex->rflags & FILTRULE_WILD2)) {
 667                 /* A non-anchored match with an infix slash and no "**"
 668                  * needs to match the last slash_cnt+1 name elements. */
 669                 slash_handling = ex->u.slash_cnt + 1;
 670         } else if (!anchored_match && !(ex->rflags & FILTRULE_WILD2_PREFIX)
 671                                    && ex->rflags & FILTRULE_WILD2) {
 672                 /* A non-anchored match with an infix or trailing "**" (but not
 673                  * a prefixed "**") needs to try matching after every slash. */
 674                 slash_handling = -1;
 675         } else {
 676                 /* The pattern matches only at the start of the path or name. */
 677                 slash_handling = 0;
 678         }
 679
 680         if (ex->rflags & FILTRULE_WILD) {
 681                 if (wildmatch_array(pattern, strings, slash_handling))
 682                         return ret_match;
 683         } else if (str_cnt > 1) {
 684                 if (litmatch_array(pattern, strings, slash_handling))
 685                         return ret_match;
 686         } else if (anchored_match) {
 687                 if (strcmp(name, pattern) == 0)
 688                         return ret_match;
 689         } else {
 690                 int l1 = strlen(name);
 691                 int l2 = strlen(pattern);
 692                 if (l2 <= l1 &&
 693                     strcmp(name+(l1-l2),pattern) == 0 &&
 694                     (l1==l2 || name[l1-(l2+1)] == '/')) {
 695                         return ret_match;
 696                 }
 697         }
 698
 699         return !ret_match;
 700 }
 701
 702 static void report_filter_result(enum logcode code, char const *name,
 703                                  filter_rule const *ent,
 704                                  int name_flags, const char *type)
 705 {
 706         /* If a trailing slash is present to match only directories,
 707          * then it is stripped out by add_rule().  So as a special
 708          * case we add it back in here. */
 709
 710         if (DEBUG_GTE(FILTER, 1)) {
 711                 static char *actions[2][2]
 712                     = { {"show", "hid"}, {"risk", "protect"} };
 713                 const char *w = who_am_i();
 714                 const char *t = name_flags & NAME_IS_XATTR ? "xattr"
 715                               : name_flags & NAME_IS_DIR ? "directory"
 716                               : "file";
 717                 rprintf(code, "[%s] %sing %s %s because of pattern %s%s%s\n",
 718                     w, actions[*w!='s'][!(ent->rflags & FILTRULE_INCLUDE)],
 719                     t, name, ent->pattern,
 720                     ent->rflags & FILTRULE_DIRECTORY ? "/" : "", type);
 721         }
 722 }
 723
 724 /* This function is used to check if a file should be included/excluded
 725  * from the list of files based on its name and type etc.  The value of
 726  * filter_level is set to either SERVER_FILTERS or ALL_FILTERS. */
 727 int name_is_excluded(const char *fname, int name_flags, int filter_level)
 728 {
 729         if (daemon_filter_list.head && check_filter(&daemon_filter_list, FLOG, fname, name_flags) < 0) {
 730                 if (!(name_flags & NAME_IS_XATTR))
 731                         errno = ENOENT;
 732                 return 1;
 733         }
 734
 735         if (filter_level != ALL_FILTERS)
 736                 return 0;
 737
 738         if (filter_list.head && check_filter(&filter_list, FINFO, fname, name_flags) < 0)
 739                 return 1;
 740
 741         return 0;
 742 }
 743
 744 /* Return -1 if file "name" is defined to be excluded by the specified
 745  * exclude list, 1 if it is included, and 0 if it was not matched. */
 746 int check_filter(filter_rule_list *listp, enum logcode code,
 747                  const char *name, int name_flags)
 748 {
 749         filter_rule *ent;
 750
 751         for (ent = listp->head; ent; ent = ent->next) {
 752                 if (ignore_perishable && ent->rflags & FILTRULE_PERISHABLE)
 753                         continue;
 754                 if (ent->rflags & FILTRULE_PERDIR_MERGE) {
 755                         int rc = check_filter(ent->u.mergelist, code, name, name_flags);
 756                         if (rc)
 757                                 return rc;
 758                         continue;
 759                 }
 760                 if (ent->rflags & FILTRULE_CVS_IGNORE) {
 761                         int rc = check_filter(&cvs_filter_list, code, name, name_flags);
 762                         if (rc)
 763                                 return rc;
 764                         continue;
 765                 }
 766                 if (rule_matches(name, ent, name_flags)) {
 767                         report_filter_result(code, name, ent, name_flags, listp->debug_type);
 768                         return ent->rflags & FILTRULE_INCLUDE ? 1 : -1;
 769                 }
 770         }
 771
 772         return 0;
 773 }
 774
 775 #define RULE_STRCMP(s,r) rule_strcmp((s), (r), sizeof (r) - 1)
 776
 777 static const uchar *rule_strcmp(const uchar *str, const char *rule, int rule_len)
 778 {
 779         if (strncmp((char*)str, rule, rule_len) != 0)
 780                 return NULL;
 781         if (isspace(str[rule_len]) || str[rule_len] == '_' || !str[rule_len])
 782                 return str + rule_len - 1;
 783         if (str[rule_len] == ',')
 784                 return str + rule_len;
 785         return NULL;
 786 }
 787
 788 #define FILTRULES_FROM_CONTAINER (FILTRULE_ABS_PATH | FILTRULE_INCLUDE \
 789                                 | FILTRULE_DIRECTORY | FILTRULE_NEGATE \
 790                                 | FILTRULE_PERISHABLE)
 791
 792 /* Gets the next include/exclude rule from *rulestr_ptr and advances
 793  * *rulestr_ptr to point beyond it.  Stores the pattern's start (within
 794  * *rulestr_ptr) and length in *pat_ptr and *pat_len_ptr, and returns a newly
 795  * allocated filter_rule containing the rest of the information.  Returns
 796  * NULL if there are no more rules in the input.
 797  *
 798  * The template provides defaults for the new rule to inherit, and the
 799  * template rflags and the xflags additionally affect parsing. */
 800 static filter_rule *parse_rule_tok(const char **rulestr_ptr,
 801                                    const filter_rule *template, int xflags,
 802                                    const char **pat_ptr, unsigned int *pat_len_ptr)
 803 {
 804         const uchar *s = (const uchar *)*rulestr_ptr;
 805         filter_rule *rule;
 806         unsigned int len;
 807
 808         if (template->rflags & FILTRULE_WORD_SPLIT) {
 809                 /* Skip over any initial whitespace. */
 810                 while (isspace(*s))
 811                         s++;
 812                 /* Update to point to real start of rule. */
 813                 *rulestr_ptr = (const char *)s;
 814         }
 815         if (!*s)
 816                 return NULL;
 817
 818         rule = new0(filter_rule);
 819
 820         /* Inherit from the template.  Don't inherit FILTRULES_SIDES; we check
 821          * that later. */
 822         rule->rflags = template->rflags & FILTRULES_FROM_CONTAINER;
 823
 824         /* Figure out what kind of a filter rule "s" is pointing at.  Note
 825          * that if FILTRULE_NO_PREFIXES is set, the rule is either an include
 826          * or an exclude based on the inheritance of the FILTRULE_INCLUDE
 827          * flag (above).  XFLG_OLD_PREFIXES indicates a compatibility mode
 828          * for old include/exclude patterns where just "+ " and "- " are
 829          * allowed as optional prefixes.  */
 830         if (template->rflags & FILTRULE_NO_PREFIXES) {
 831                 if (*s == '!' && template->rflags & FILTRULE_CVS_IGNORE)
 832                         rule->rflags |= FILTRULE_CLEAR_LIST; /* Tentative! */
 833         } else if (xflags & XFLG_OLD_PREFIXES) {
 834                 if (*s == '-' && s[1] == ' ') {
 835                         rule->rflags &= ~FILTRULE_INCLUDE;
 836                         s += 2;
 837                 } else if (*s == '+' && s[1] == ' ') {
 838                         rule->rflags |= FILTRULE_INCLUDE;
 839                         s += 2;
 840                 } else if (*s == '!')
 841                         rule->rflags |= FILTRULE_CLEAR_LIST; /* Tentative! */
 842         } else {
 843                 char ch = 0;
 844                 BOOL prefix_specifies_side = False;
 845                 switch (*s) {
 846                 case 'c':
 847                         if ((s = RULE_STRCMP(s, "clear")) != NULL)
 848                                 ch = '!';
 849                         break;
 850                 case 'd':
 851                         if ((s = RULE_STRCMP(s, "dir-merge")) != NULL)
 852                                 ch = ':';
 853                         break;
 854                 case 'e':
 855                         if ((s = RULE_STRCMP(s, "exclude")) != NULL)
 856                                 ch = '-';
 857                         break;
 858                 case 'h':
 859                         if ((s = RULE_STRCMP(s, "hide")) != NULL)
 860                                 ch = 'H';
 861                         break;
 862                 case 'i':
 863                         if ((s = RULE_STRCMP(s, "include")) != NULL)
 864                                 ch = '+';
 865                         break;
 866                 case 'm':
 867                         if ((s = RULE_STRCMP(s, "merge")) != NULL)
 868                                 ch = '.';
 869                         break;
 870                 case 'p':
 871                         if ((s = RULE_STRCMP(s, "protect")) != NULL)
 872                                 ch = 'P';
 873                         break;
 874                 case 'r':
 875                         if ((s = RULE_STRCMP(s, "risk")) != NULL)
 876                                 ch = 'R';
 877                         break;
 878                 case 's':
 879                         if ((s = RULE_STRCMP(s, "show")) != NULL)
 880                                 ch = 'S';
 881                         break;
 882                 default:
 883                         ch = *s;
 884                         if (s[1] == ',')
 885                                 s++;
 886                         break;
 887                 }
 888                 switch (ch) {
 889                 case ':':
 890                         rule->rflags |= FILTRULE_PERDIR_MERGE
 891                                       | FILTRULE_FINISH_SETUP;
 892                         /* FALL THROUGH */
 893                 case '.':
 894                         rule->rflags |= FILTRULE_MERGE_FILE;
 895                         break;
 896                 case '+':
 897                         rule->rflags |= FILTRULE_INCLUDE;
 898                         break;
 899                 case '-':
 900                         break;
 901                 case 'S':
 902                         rule->rflags |= FILTRULE_INCLUDE;
 903                         /* FALL THROUGH */
 904                 case 'H':
 905                         rule->rflags |= FILTRULE_SENDER_SIDE;
 906                         prefix_specifies_side = True;
 907                         break;
 908                 case 'R':
 909                         rule->rflags |= FILTRULE_INCLUDE;
 910                         /* FALL THROUGH */
 911                 case 'P':
 912                         rule->rflags |= FILTRULE_RECEIVER_SIDE;
 913                         prefix_specifies_side = True;
 914                         break;
 915                 case '!':
 916                         rule->rflags |= FILTRULE_CLEAR_LIST;
 917                         break;
 918                 default:
 919                         rprintf(FERROR, "Unknown filter rule: `%s'\n", *rulestr_ptr);
 920                         exit_cleanup(RERR_SYNTAX);
 921                 }
 922                 while (ch != '!' && *++s && *s != ' ' && *s != '_') {
 923                         if (template->rflags & FILTRULE_WORD_SPLIT && isspace(*s)) {
 924                                 s--;
 925                                 break;
 926                         }
 927                         switch (*s) {
 928                         default:
 929                             invalid:
 930                                 rprintf(FERROR,
 931                                         "invalid modifier '%c' at position %d in filter rule: %s\n",
 932                                         *s, (int)(s - (const uchar *)*rulestr_ptr), *rulestr_ptr);
 933                                 exit_cleanup(RERR_SYNTAX);
 934                         case '-':
 935                                 if (!BITS_SETnUNSET(rule->rflags, FILTRULE_MERGE_FILE, FILTRULE_NO_PREFIXES))
 936                                         goto invalid;
 937                                 rule->rflags |= FILTRULE_NO_PREFIXES;
 938                                 break;
 939                         case '+':
 940                                 if (!BITS_SETnUNSET(rule->rflags, FILTRULE_MERGE_FILE, FILTRULE_NO_PREFIXES))
 941                                         goto invalid;
 942                                 rule->rflags |= FILTRULE_NO_PREFIXES
 943                                               | FILTRULE_INCLUDE;
 944                                 break;
 945                         case '/':
 946                                 rule->rflags |= FILTRULE_ABS_PATH;
 947                                 break;
 948                         case '!':
 949                                 /* Negation really goes with the pattern, so it
 950                                  * isn't useful as a merge-file default. */
 951                                 if (rule->rflags & FILTRULE_MERGE_FILE)
 952                                         goto invalid;
 953                                 rule->rflags |= FILTRULE_NEGATE;
 954                                 break;
 955                         case 'C':
 956                                 if (rule->rflags & FILTRULE_NO_PREFIXES || prefix_specifies_side)
 957                                         goto invalid;
 958                                 rule->rflags |= FILTRULE_NO_PREFIXES
 959                                               | FILTRULE_WORD_SPLIT
 960                                               | FILTRULE_NO_INHERIT
 961                                               | FILTRULE_CVS_IGNORE;
 962                                 break;
 963                         case 'e':
 964                                 if (!(rule->rflags & FILTRULE_MERGE_FILE))
 965                                         goto invalid;
 966                                 rule->rflags |= FILTRULE_EXCLUDE_SELF;
 967                                 break;
 968                         case 'n':
 969                                 if (!(rule->rflags & FILTRULE_MERGE_FILE))
 970                                         goto invalid;
 971                                 rule->rflags |= FILTRULE_NO_INHERIT;
 972                                 break;
 973                         case 'p':
 974                                 rule->rflags |= FILTRULE_PERISHABLE;
 975                                 break;
 976                         case 'r':
 977                                 if (prefix_specifies_side)
 978                                         goto invalid;
 979                                 rule->rflags |= FILTRULE_RECEIVER_SIDE;
 980                                 break;
 981                         case 's':
 982                                 if (prefix_specifies_side)
 983                                         goto invalid;
 984                                 rule->rflags |= FILTRULE_SENDER_SIDE;
 985                                 break;
 986                         case 'w':
 987                                 if (!(rule->rflags & FILTRULE_MERGE_FILE))
 988                                         goto invalid;
 989                                 rule->rflags |= FILTRULE_WORD_SPLIT;
 990                                 break;
 991                         case 'x':
 992                                 rule->rflags |= FILTRULE_XATTR;
 993                                 saw_xattr_filter = 1;
 994                                 break;
 995                         }
 996                 }
 997                 if (*s)
 998                         s++;
 999         }
1000         if (template->rflags & FILTRULES_SIDES) {
1001                 if (rule->rflags & FILTRULES_SIDES) {
1002                         /* The filter and template both specify side(s).  This
1003                          * is dodgy (and won't work correctly if the template is
1004                          * a one-sided per-dir merge rule), so reject it. */
1005                         rprintf(FERROR,
1006                                 "specified-side merge file contains specified-side filter: %s\n",
1007                                 *rulestr_ptr);
1008                         exit_cleanup(RERR_SYNTAX);
1009                 }
1010                 rule->rflags |= template->rflags & FILTRULES_SIDES;
1011         }
1012
1013         if (template->rflags & FILTRULE_WORD_SPLIT) {
1014                 const uchar *cp = s;
1015                 /* Token ends at whitespace or the end of the string. */
1016                 while (!isspace(*cp) && *cp != '\0')
1017                         cp++;
1018                 len = cp - s;
1019         } else
1020                 len = strlen((char*)s);
1021
1022         if (rule->rflags & FILTRULE_CLEAR_LIST) {
1023                 if (!(rule->rflags & FILTRULE_NO_PREFIXES)
1024                  && !(xflags & XFLG_OLD_PREFIXES) && len) {
1025                         rprintf(FERROR,
1026                                 "'!' rule has trailing characters: %s\n", *rulestr_ptr);
1027                         exit_cleanup(RERR_SYNTAX);
1028                 }
1029                 if (len > 1)
1030                         rule->rflags &= ~FILTRULE_CLEAR_LIST;
1031         } else if (!len && !(rule->rflags & FILTRULE_CVS_IGNORE)) {
1032                 rprintf(FERROR, "unexpected end of filter rule: %s\n", *rulestr_ptr);
1033                 exit_cleanup(RERR_SYNTAX);
1034         }
1035
1036         /* --delete-excluded turns an un-modified include/exclude into a sender-side rule.  */
1037         if (delete_excluded
1038          && !(rule->rflags & (FILTRULES_SIDES|FILTRULE_MERGE_FILE|FILTRULE_PERDIR_MERGE)))
1039                 rule->rflags |= FILTRULE_SENDER_SIDE;
1040
1041         *pat_ptr = (const char *)s;
1042         *pat_len_ptr = len;
1043         *rulestr_ptr = *pat_ptr + len;
1044         return rule;
1045 }
1046
1047 static void get_cvs_excludes(uint32 rflags)
1048 {
1049         static int initialized = 0;
1050         char *p, fname[MAXPATHLEN];
1051
1052         if (initialized)
1053                 return;
1054         initialized = 1;
1055
1056         parse_filter_str(&cvs_filter_list, DEFAULT_CVSIGNORE,
1057                          rule_template(rflags | (protocol_version >= 30 ? FILTRULE_PERISHABLE : 0)),
1058                          0);
1059
1060         p = module_id >= 0 && lp_use_chroot(module_id) ? "/" : getenv("HOME");
1061         if (p && pathjoin(fname, MAXPATHLEN, p, ".cvsignore") < MAXPATHLEN)
1062                 parse_filter_file(&cvs_filter_list, fname, rule_template(rflags), 0);
1063
1064         parse_filter_str(&cvs_filter_list, getenv("CVSIGNORE"), rule_template(rflags), 0);
1065 }
1066
1067 const filter_rule *rule_template(uint32 rflags)
1068 {
1069         static filter_rule template; /* zero-initialized */
1070         template.rflags = rflags;
1071         return &template;
1072 }
1073
1074 void parse_filter_str(filter_rule_list *listp, const char *rulestr,
1075                      const filter_rule *template, int xflags)
1076 {
1077         filter_rule *rule;
1078         const char *pat;
1079         unsigned int pat_len;
1080
1081         if (!rulestr)
1082                 return;
1083
1084         while (1) {
1085                 uint32 new_rflags;
1086
1087                 /* Remember that the returned string is NOT '\0' terminated! */
1088                 if (!(rule = parse_rule_tok(&rulestr, template, xflags, &pat, &pat_len)))
1089                         break;
1090
1091                 if (pat_len >= MAXPATHLEN) {
1092                         rprintf(FERROR, "discarding over-long filter: %.*s\n",
1093                                 (int)pat_len, pat);
1094                     free_continue:
1095                         free_filter(rule);
1096                         continue;
1097                 }
1098
1099                 new_rflags = rule->rflags;
1100                 if (new_rflags & FILTRULE_CLEAR_LIST) {
1101                         if (DEBUG_GTE(FILTER, 2)) {
1102                                 rprintf(FINFO,
1103                                         "[%s] clearing filter list%s\n",
1104                                         who_am_i(), listp->debug_type);
1105                         }
1106                         pop_filter_list(listp);
1107                         listp->head = NULL;
1108                         goto free_continue;
1109                 }
1110
1111                 if (new_rflags & FILTRULE_MERGE_FILE) {
1112                         if (!pat_len) {
1113                                 pat = ".cvsignore";
1114                                 pat_len = 10;
1115                         }
1116                         if (new_rflags & FILTRULE_EXCLUDE_SELF) {
1117                                 const char *name;
1118                                 filter_rule *excl_self;
1119
1120                                 excl_self = new0(filter_rule);
1121                                 /* Find the beginning of the basename and add an exclude for it. */
1122                                 for (name = pat + pat_len; name > pat && name[-1] != '/'; name--) {}
1123                                 add_rule(listp, name, (pat + pat_len) - name, excl_self, 0);
1124                                 rule->rflags &= ~FILTRULE_EXCLUDE_SELF;
1125                         }
1126                         if (new_rflags & FILTRULE_PERDIR_MERGE) {
1127                                 if (parent_dirscan) {
1128                                         const char *p;
1129                                         unsigned int len = pat_len;
1130                                         if ((p = parse_merge_name(pat, &len, module_dirlen)))
1131                                                 add_rule(listp, p, len, rule, 0);
1132                                         else
1133                                                 free_filter(rule);
1134                                         continue;
1135                                 }
1136                         } else {
1137                                 const char *p;
1138                                 unsigned int len = pat_len;
1139                                 if ((p = parse_merge_name(pat, &len, 0)))
1140                                         parse_filter_file(listp, p, rule, XFLG_FATAL_ERRORS);
1141                                 free_filter(rule);
1142                                 continue;
1143                         }
1144                 }
1145
1146                 add_rule(listp, pat, pat_len, rule, xflags);
1147
1148                 if (new_rflags & FILTRULE_CVS_IGNORE
1149                     && !(new_rflags & FILTRULE_MERGE_FILE))
1150                         get_cvs_excludes(new_rflags);
1151         }
1152 }
1153
1154 void parse_filter_file(filter_rule_list *listp, const char *fname, const filter_rule *template, int xflags)
1155 {
1156         FILE *fp;
1157         char line[BIGPATHBUFLEN];
1158         char *eob = line + sizeof line - 1;
1159         BOOL word_split = (template->rflags & FILTRULE_WORD_SPLIT) != 0;
1160
1161         if (!fname || !*fname)
1162                 return;
1163
1164         if (*fname != '-' || fname[1] || am_server) {
1165                 if (daemon_filter_list.head) {
1166                         strlcpy(line, fname, sizeof line);
1167                         clean_fname(line, CFN_COLLAPSE_DOT_DOT_DIRS);
1168                         if (check_filter(&daemon_filter_list, FLOG, line, 0) < 0)
1169                                 fp = NULL;
1170                         else
1171                                 fp = fopen(line, "rb");
1172                 } else
1173                         fp = fopen(fname, "rb");
1174         } else
1175                 fp = stdin;
1176
1177         if (DEBUG_GTE(FILTER, 2)) {
1178                 rprintf(FINFO, "[%s] parse_filter_file(%s,%x,%x)%s\n",
1179                         who_am_i(), fname, template->rflags, xflags,
1180                         fp ? "" : " [not found]");
1181         }
1182
1183         if (!fp) {
1184                 if (xflags & XFLG_FATAL_ERRORS) {
1185                         rsyserr(FERROR, errno,
1186                                 "failed to open %sclude file %s",
1187                                 template->rflags & FILTRULE_INCLUDE ? "in" : "ex",
1188                                 fname);
1189                         exit_cleanup(RERR_FILEIO);
1190                 }
1191                 return;
1192         }
1193         dirbuf[dirbuf_len] = '\0';
1194
1195         while (1) {
1196                 char *s = line;
1197                 int ch, overflow = 0;
1198                 while (1) {
1199                         if ((ch = getc(fp)) == EOF) {
1200                                 if (ferror(fp) && errno == EINTR) {
1201                                         clearerr(fp);
1202                                         continue;
1203                                 }
1204                                 break;
1205                         }
1206                         if (word_split && isspace(ch))
1207                                 break;
1208                         if (eol_nulls? !ch : (ch == '\n' || ch == '\r'))
1209                                 break;
1210                         if (s < eob)
1211                                 *s++ = ch;
1212                         else
1213                                 overflow = 1;
1214                 }
1215                 if (overflow) {
1216                         rprintf(FERROR, "discarding over-long filter: %s...\n", line);
1217                         s = line;
1218                 }
1219                 *s = '\0';
1220                 /* Skip an empty token and (when line parsing) comments. */
1221                 if (*line && (word_split || (*line != ';' && *line != '#')))
1222                         parse_filter_str(listp, line, template, xflags);
1223                 if (ch == EOF)
1224                         break;
1225         }
1226         fclose(fp);
1227 }
1228
1229 /* If the "for_xfer" flag is set, the prefix is made compatible with the
1230  * current protocol_version (if possible) or a NULL is returned (if not
1231  * possible). */
1232 char *get_rule_prefix(filter_rule *rule, const char *pat, int for_xfer,
1233                       unsigned int *plen_ptr)
1234 {
1235         static char buf[MAX_RULE_PREFIX+1];
1236         char *op = buf;
1237         int legal_len = for_xfer && protocol_version < 29 ? 1 : MAX_RULE_PREFIX-1;
1238
1239         if (rule->rflags & FILTRULE_PERDIR_MERGE) {
1240                 if (legal_len == 1)
1241                         return NULL;
1242                 *op++ = ':';
1243         } else if (rule->rflags & FILTRULE_INCLUDE)
1244                 *op++ = '+';
1245         else if (legal_len != 1
1246             || ((*pat == '-' || *pat == '+') && pat[1] == ' '))
1247                 *op++ = '-';
1248         else
1249                 legal_len = 0;
1250
1251         if (rule->rflags & FILTRULE_ABS_PATH)
1252                 *op++ = '/';
1253         if (rule->rflags & FILTRULE_NEGATE)
1254                 *op++ = '!';
1255         if (rule->rflags & FILTRULE_CVS_IGNORE)
1256                 *op++ = 'C';
1257         else {
1258                 if (rule->rflags & FILTRULE_NO_INHERIT)
1259                         *op++ = 'n';
1260                 if (rule->rflags & FILTRULE_WORD_SPLIT)
1261                         *op++ = 'w';
1262                 if (rule->rflags & FILTRULE_NO_PREFIXES) {
1263                         if (rule->rflags & FILTRULE_INCLUDE)
1264                                 *op++ = '+';
1265                         else
1266                                 *op++ = '-';
1267                 }
1268         }
1269         if (rule->rflags & FILTRULE_EXCLUDE_SELF)
1270                 *op++ = 'e';
1271         if (rule->rflags & FILTRULE_XATTR)
1272                 *op++ = 'x';
1273         if (rule->rflags & FILTRULE_SENDER_SIDE
1274             && (!for_xfer || protocol_version >= 29))
1275                 *op++ = 's';
1276         if (rule->rflags & FILTRULE_RECEIVER_SIDE
1277             && (!for_xfer || protocol_version >= 29
1278              || (delete_excluded && am_sender)))
1279                 *op++ = 'r';
1280         if (rule->rflags & FILTRULE_PERISHABLE) {
1281                 if (!for_xfer || protocol_version >= 30)
1282                         *op++ = 'p';
1283                 else if (am_sender)
1284                         return NULL;
1285         }
1286         if (op - buf > legal_len)
1287                 return NULL;
1288         if (legal_len)
1289                 *op++ = ' ';
1290         *op = '\0';
1291         if (plen_ptr)
1292                 *plen_ptr = op - buf;
1293         return buf;
1294 }
1295
1296 static void send_rules(int f_out, filter_rule_list *flp)
1297 {
1298         filter_rule *ent, *prev = NULL;
1299
1300         for (ent = flp->head; ent; ent = ent->next) {
1301                 unsigned int len, plen, dlen;
1302                 int elide = 0;
1303                 char *p;
1304
1305                 /* Note we need to check delete_excluded here in addition to
1306                  * the code in parse_rule_tok() because some rules may have
1307                  * been added before we found the --delete-excluded option.
1308                  * We must also elide any CVS merge-file rules to avoid a
1309                  * backward compatibility problem, and we elide any no-prefix
1310                  * merge files as an optimization (since they can only have
1311                  * include/exclude rules). */
1312                 if (ent->rflags & FILTRULE_SENDER_SIDE)
1313                         elide = am_sender ? 1 : -1;
1314                 if (ent->rflags & FILTRULE_RECEIVER_SIDE)
1315                         elide = elide ? 0 : am_sender ? -1 : 1;
1316                 else if (delete_excluded && !elide
1317                  && (!(ent->rflags & FILTRULE_PERDIR_MERGE)
1318                   || ent->rflags & FILTRULE_NO_PREFIXES))
1319                         elide = am_sender ? 1 : -1;
1320                 if (elide < 0) {
1321                         if (prev)
1322                                 prev->next = ent->next;
1323                         else
1324                                 flp->head = ent->next;
1325                 } else
1326                         prev = ent;
1327                 if (elide > 0)
1328                         continue;
1329                 if (ent->rflags & FILTRULE_CVS_IGNORE
1330                     && !(ent->rflags & FILTRULE_MERGE_FILE)) {
1331                         int f = am_sender || protocol_version < 29 ? f_out : -2;
1332                         send_rules(f, &cvs_filter_list);
1333                         if (f == f_out)
1334                                 continue;
1335                 }
1336                 p = get_rule_prefix(ent, ent->pattern, 1, &plen);
1337                 if (!p) {
1338                         rprintf(FERROR,
1339                                 "filter rules are too modern for remote rsync.\n");
1340                         exit_cleanup(RERR_PROTOCOL);
1341                 }
1342                 if (f_out < 0)
1343                         continue;
1344                 len = strlen(ent->pattern);
1345                 dlen = ent->rflags & FILTRULE_DIRECTORY ? 1 : 0;
1346                 if (!(plen + len + dlen))
1347                         continue;
1348                 write_int(f_out, plen + len + dlen);
1349                 if (plen)
1350                         write_buf(f_out, p, plen);
1351                 write_buf(f_out, ent->pattern, len);
1352                 if (dlen)
1353                         write_byte(f_out, '/');
1354         }
1355         flp->tail = prev;
1356 }
1357
1358 /* This is only called by the client. */
1359 void send_filter_list(int f_out)
1360 {
1361         int receiver_wants_list = prune_empty_dirs
1362             || (delete_mode && (!delete_excluded || protocol_version >= 29));
1363
1364         if (local_server || (am_sender && !receiver_wants_list))
1365                 f_out = -1;
1366         if (cvs_exclude && am_sender) {
1367                 if (protocol_version >= 29)
1368                         parse_filter_str(&filter_list, ":C", rule_template(0), 0);
1369                 parse_filter_str(&filter_list, "-C", rule_template(0), 0);
1370         }
1371
1372         send_rules(f_out, &filter_list);
1373
1374         if (f_out >= 0)
1375                 write_int(f_out, 0);
1376
1377         if (cvs_exclude) {
1378                 if (!am_sender || protocol_version < 29)
1379                         parse_filter_str(&filter_list, ":C", rule_template(0), 0);
1380                 if (!am_sender)
1381                         parse_filter_str(&filter_list, "-C", rule_template(0), 0);
1382         }
1383 }
1384
1385 /* This is only called by the server. */
1386 void recv_filter_list(int f_in)
1387 {
1388         char line[BIGPATHBUFLEN];
1389         int xflags = protocol_version >= 29 ? 0 : XFLG_OLD_PREFIXES;
1390         int receiver_wants_list = prune_empty_dirs
1391             || (delete_mode && (!delete_excluded || protocol_version >= 29));
1392         unsigned int len;
1393
1394         if (!local_server && (am_sender || receiver_wants_list)) {
1395                 while ((len = read_int(f_in)) != 0) {
1396                         if (len >= sizeof line)
1397                                 overflow_exit("recv_rules");
1398                         read_sbuf(f_in, line, len);
1399                         parse_filter_str(&filter_list, line, rule_template(0), xflags);
1400                 }
1401         }
1402
1403         if (cvs_exclude) {
1404                 if (local_server || am_sender || protocol_version < 29)
1405                         parse_filter_str(&filter_list, ":C", rule_template(0), 0);
1406                 if (local_server || am_sender)
1407                         parse_filter_str(&filter_list, "-C", rule_template(0), 0);
1408         }
1409
1410         if (local_server) /* filter out any rules that aren't for us. */
1411                 send_rules(-1, &filter_list);
1412 }