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