2 * Handle the mapping of uid/gid and user/group names between systems.
4 * Copyright (C) 1996 Andrew Tridgell
5 * Copyright (C) 1996 Paul Mackerras
6 * Copyright (C) 2004-2020 Wayne Davison
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 3 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, visit the http://fsf.org website.
22 /* If the source username/group does not exist on the target then use
23 * the numeric IDs. Never do any mapping for uid=0 or gid=0 as these
32 extern int preserve_uid;
33 extern int preserve_gid;
34 extern int preserve_acls;
35 extern int numeric_ids;
38 extern char *groupmap;
42 # define GETGROUPS_T gid_t
46 #define NFLAGS_WILD_NAME_MATCH (1<<0)
47 #define NFLAGS_NAME_MATCH (1<<1)
61 static struct idlist *uidlist, *uidmap;
62 static struct idlist *gidlist, *gidmap;
64 static id_t id_parse(const char *num_str)
67 const char *cp = num_str;
72 rprintf(FERROR, "Invalid ID number: %s\n", num_str);
73 exit_cleanup(RERR_SYNTAX);
75 tmp = num * 10 + *cp++ - '0';
84 static struct idlist *add_to_list(struct idlist **root, id_t id, union name_or_id noiu,
85 id_t id2, uint16 flags)
87 struct idlist *node = new(struct idlist);
89 out_of_memory("add_to_list");
99 /* turn a uid into a user name */
100 char *uid_to_user(uid_t uid)
102 struct passwd *pass = getpwuid(uid);
104 return strdup(pass->pw_name);
108 /* turn a gid into a group name */
109 char *gid_to_group(gid_t gid)
111 struct group *grp = getgrgid(gid);
113 return strdup(grp->gr_name);
117 /* Parse a user name or (optionally) a number into a uid */
118 int user_to_uid(const char *name, uid_t *uid_p, BOOL num_ok)
123 if (num_ok && name[strspn(name, "0123456789")] == '\0') {
124 *uid_p = id_parse(name);
127 if (!(pass = getpwnam(name)))
129 *uid_p = pass->pw_uid;
133 /* Parse a group name or (optionally) a number into a gid */
134 int group_to_gid(const char *name, gid_t *gid_p, BOOL num_ok)
139 if (num_ok && name[strspn(name, "0123456789")] == '\0') {
140 *gid_p = id_parse(name);
143 if (!(grp = getgrnam(name)))
145 *gid_p = grp->gr_gid;
149 static int is_in_group(gid_t gid)
151 #ifdef HAVE_GETGROUPS
152 static gid_t last_in;
153 static int ngroups = -2, last_out = -1;
154 static GETGROUPS_T *gidset;
157 if (gid == last_in && last_out >= 0)
160 if ((ngroups = getgroups(0, NULL)) < 0)
162 gidset = new_array(GETGROUPS_T, ngroups+1);
164 out_of_memory("is_in_group");
166 ngroups = getgroups(ngroups, gidset);
167 /* The default gid might not be in the list on some systems. */
168 for (n = 0; n < ngroups; n++) {
169 if (gidset[n] == our_gid)
173 gidset[ngroups++] = our_gid;
174 if (DEBUG_GTE(OWN, 2)) {
176 char *gidbuf = new_array(char, ngroups*21+32);
178 out_of_memory("is_in_group");
179 pos = snprintf(gidbuf, 32, "process has %d gid%s: ", ngroups, ngroups == 1? "" : "s");
180 for (n = 0; n < ngroups; n++) {
181 pos += snprintf(gidbuf+pos, 21, " %d", (int)gidset[n]);
183 rprintf(FINFO, "%s\n", gidbuf);
189 for (n = 0; n < ngroups; n++) {
190 if (gidset[n] == gid)
196 return gid == our_gid;
200 /* Add a uid/gid to its list of ids. Only called on receiving side. */
201 static struct idlist *recv_add_id(struct idlist **idlist_ptr, struct idlist *idmap,
202 id_t id, const char *name)
205 union name_or_id noiu;
209 noiu.name = name; /* ensure that add_to_list() gets the raw value. */
213 for (node = idmap; node; node = node->next) {
214 if (node->flags & NFLAGS_WILD_NAME_MATCH) {
215 if (!wildmatch(node->u.name, name))
217 } else if (node->flags & NFLAGS_NAME_MATCH) {
218 if (strcmp(node->u.name, name) != 0)
220 } else if (node->u.max_id) {
221 if (id < node->id || id > node->u.max_id)
231 else if (*name && id) {
232 if (idlist_ptr == &uidlist) {
234 id2 = user_to_uid(name, &uid, False) ? uid : id;
237 id2 = group_to_gid(name, &gid, False) ? gid : id;
242 flag = idlist_ptr == &gidlist && !am_root && !is_in_group(id2) ? FLAG_SKIP_GROUP : 0;
243 node = add_to_list(idlist_ptr, id, noiu, id2, flag);
245 if (DEBUG_GTE(OWN, 2)) {
246 rprintf(FINFO, "%sid %u(%s) maps to %u\n",
247 idlist_ptr == &uidlist ? "u" : "g",
248 (unsigned)id, name, (unsigned)id2);
254 /* this function is a definite candidate for a faster algorithm */
255 uid_t match_uid(uid_t uid)
257 static struct idlist *last = NULL;
260 if (last && uid == last->id)
263 for (list = uidlist; list; list = list->next) {
269 list = recv_add_id(&uidlist, uidmap, uid, NULL);
275 gid_t match_gid(gid_t gid, uint16 *flags_ptr)
277 static struct idlist *last = NULL;
280 if (last && gid == last->id)
283 for (list = gidlist; list; list = list->next) {
288 list = recv_add_id(&gidlist, gidmap, gid, NULL);
292 if (flags_ptr && list->flags & FLAG_SKIP_GROUP)
293 *flags_ptr |= FLAG_SKIP_GROUP;
297 /* Add a uid to the list of uids. Only called on sending side. */
298 const char *add_uid(uid_t uid)
302 union name_or_id noiu;
304 if (uid == 0) /* don't map root */
307 for (list = uidlist; list; list = list->next) {
312 noiu.name = uid_to_user(uid);
313 node = add_to_list(&uidlist, uid, noiu, 0, 0);
317 /* Add a gid to the list of gids. Only called on sending side. */
318 const char *add_gid(gid_t gid)
322 union name_or_id noiu;
324 if (gid == 0) /* don't map root */
327 for (list = gidlist; list; list = list->next) {
332 noiu.name = gid_to_group(gid);
333 node = add_to_list(&gidlist, gid, noiu, 0, 0);
337 /* send a complete uid/gid mapping to the peer */
338 void send_id_list(int f)
342 if (preserve_uid || preserve_acls) {
344 /* we send sequences of uid/byte-length/name */
345 for (list = uidlist; list; list = list->next) {
348 len = strlen(list->u.name);
349 write_varint30(f, list->id);
351 write_buf(f, list->u.name, len);
354 /* terminate the uid list with a 0 uid. We explicitly exclude
356 write_varint30(f, 0);
359 if (preserve_gid || preserve_acls) {
361 for (list = gidlist; list; list = list->next) {
364 len = strlen(list->u.name);
365 write_varint30(f, list->id);
367 write_buf(f, list->u.name, len);
369 write_varint30(f, 0);
373 uid_t recv_user_name(int f, uid_t uid)
376 int len = read_byte(f);
377 char *name = new_array(char, len+1);
379 out_of_memory("recv_user_name");
380 read_sbuf(f, name, len);
381 if (numeric_ids < 0) {
385 node = recv_add_id(&uidlist, uidmap, uid, name); /* node keeps name's memory */
389 gid_t recv_group_name(int f, gid_t gid, uint16 *flags_ptr)
392 int len = read_byte(f);
393 char *name = new_array(char, len+1);
395 out_of_memory("recv_group_name");
396 read_sbuf(f, name, len);
397 if (numeric_ids < 0) {
401 node = recv_add_id(&gidlist, gidmap, gid, name); /* node keeps name's memory */
402 if (flags_ptr && node->flags & FLAG_SKIP_GROUP)
403 *flags_ptr |= FLAG_SKIP_GROUP;
407 /* recv a complete uid/gid mapping from the peer and map the uid/gid
408 * in the file list to local names */
409 void recv_id_list(int f, struct file_list *flist)
414 if ((preserve_uid || preserve_acls) && numeric_ids <= 0) {
415 /* read the uid list */
416 while ((id = read_varint30(f)) != 0)
417 recv_user_name(f, id);
420 if ((preserve_gid || preserve_acls) && numeric_ids <= 0) {
421 /* read the gid list */
422 while ((id = read_varint30(f)) != 0)
423 recv_group_name(f, id, NULL);
426 /* Now convert all the uids/gids from sender values to our values. */
428 if (preserve_acls && (!numeric_ids || usermap || groupmap))
431 if (am_root && preserve_uid && (!numeric_ids || usermap)) {
432 for (i = 0; i < flist->used; i++)
433 F_OWNER(flist->files[i]) = match_uid(F_OWNER(flist->files[i]));
435 if (preserve_gid && (!am_root || !numeric_ids || groupmap)) {
436 for (i = 0; i < flist->used; i++) {
437 F_GROUP(flist->files[i]) = match_gid(F_GROUP(flist->files[i]), &flist->files[i]->flags);
442 void parse_name_map(char *map, BOOL usernames)
444 struct idlist **idmap_ptr = usernames ? &uidmap : &gidmap;
445 struct idlist **idlist_ptr = usernames ? &uidlist : &gidlist;
446 char *colon, *cp = map + strlen(map);
447 union name_or_id noiu;
451 /* Parse the list in reverse, so the order in the struct is right. */
453 while (cp > map && cp[-1] != ',') cp--;
454 if (!(colon = strchr(cp, ':'))) {
455 rprintf(FERROR, "No colon found in --%smap: %s\n",
456 usernames ? "user" : "group", cp);
457 exit_cleanup(RERR_SYNTAX);
460 rprintf(FERROR, "No name found after colon --%smap: %s\n",
461 usernames ? "user" : "group", cp);
462 exit_cleanup(RERR_SYNTAX);
467 char *dash = strchr(cp, '-');
468 if (strspn(cp, "0123456789-") != (size_t)(colon - cp)
469 || (dash && (!dash[1] || strchr(dash+1, '-')))) {
470 rprintf(FERROR, "Invalid number in --%smap: %s\n",
471 usernames ? "user" : "group", cp);
472 exit_cleanup(RERR_SYNTAX);
476 noiu.max_id = id_parse(dash+1);
483 } else if (strpbrk(cp, "*[?")) {
484 flags = NFLAGS_WILD_NAME_MATCH;
488 flags = NFLAGS_NAME_MATCH;
495 if (user_to_uid(colon+1, &uid, True))
496 add_to_list(idmap_ptr, id1, noiu, uid, flags);
498 rprintf(FERROR, "Unknown --usermap name on receiver: %s\n", colon+1);
502 if (group_to_gid(colon+1, &gid, True))
503 add_to_list(idmap_ptr, id1, noiu, gid, flags);
505 rprintf(FERROR, "Unknown --groupmap name on receiver: %s\n", colon+1);
512 *--cp = '\0'; /* replace comma */
515 /* The 0 user/group doesn't get its name sent, so add it explicitly. */
516 recv_add_id(idlist_ptr, *idmap_ptr, 0, numeric_ids ? NULL : usernames ? uid_to_user(0) : gid_to_group(0));
519 #ifdef HAVE_GETGROUPLIST
520 const char *getallgroups(uid_t uid, item_list *gid_list)
526 if ((pw = getpwuid(uid)) == NULL)
527 return "getpwuid failed";
529 gid_list->count = 0; /* We're overwriting any items in the list */
530 (void)EXPAND_ITEM_LIST(gid_list, gid_t, 32);
531 size = gid_list->malloced;
533 /* Get all the process's groups, with the pw_gid group first. */
534 if (getgrouplist(pw->pw_name, pw->pw_gid, gid_list->items, &size) < 0) {
535 if (size > (int)gid_list->malloced) {
536 gid_list->count = gid_list->malloced;
537 (void)EXPAND_ITEM_LIST(gid_list, gid_t, size);
538 if (getgrouplist(pw->pw_name, pw->pw_gid, gid_list->items, &size) < 0)
543 return "getgrouplist failed";
545 gid_list->count = size;
546 gid_array = gid_list->items;
548 /* Paranoia: is the default group not first in the list? */
549 if (gid_array[0] != pw->pw_gid) {
551 for (j = 1; j < size; j++) {
552 if (gid_array[j] == pw->pw_gid)
555 if (j == size) { /* The default group wasn't found! */
556 (void)EXPAND_ITEM_LIST(gid_list, gid_t, size+1);
557 gid_array = gid_list->items;
559 gid_array[j] = gid_array[0];
560 gid_array[0] = pw->pw_gid;