diff options
Diffstat (limited to 'xattrs.c')
| -rw-r--r-- | xattrs.c | 1274 |
1 files changed, 1274 insertions, 0 deletions
diff --git a/xattrs.c b/xattrs.c new file mode 100644 index 0000000..26e50a6 --- /dev/null +++ b/xattrs.c @@ -0,0 +1,1274 @@ +/* + * Extended Attribute support for rsync. + * Written by Jay Fenlason, vaguely based on the ACLs patch. + * + * Copyright (C) 2004 Red Hat, Inc. + * Copyright (C) 2006-2022 Wayne Davison + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, visit the http://fsf.org website. + */ + +#include "rsync.h" +#include "ifuncs.h" +#include "inums.h" +#include "lib/sysxattrs.h" + +#ifdef SUPPORT_XATTRS + +extern int dry_run; +extern int am_root; +extern int am_sender; +extern int am_generator; +extern int read_only; +extern int list_only; +extern int preserve_xattrs; +extern int preserve_links; +extern int preserve_devices; +extern int preserve_specials; +extern int checksum_seed; +extern int saw_xattr_filter; + +extern struct name_num_item *xattr_sum_nni; +extern int xattr_sum_len; + +#define RSYNC_XAL_INITIAL 5 +#define RSYNC_XAL_LIST_INITIAL 100 + +#define MAX_XATTR_DIGEST_LEN MD5_DIGEST_LEN +#define MAX_FULL_DATUM 32 + +#define HAS_PREFIX(str, prfx) (*(str) == *(prfx) && strncmp(str, prfx, sizeof (prfx) - 1) == 0) + +#define XATTR_ABBREV(x) ((size_t)((x).name - (x).datum) < (x).datum_len) + +#define XSTATE_ABBREV 1 +#define XSTATE_DONE 2 +#define XSTATE_TODO 3 + +#define USER_PREFIX "user." +#define UPRE_LEN ((int)sizeof USER_PREFIX - 1) +#define SYSTEM_PREFIX "system." +#define SPRE_LEN ((int)sizeof SYSTEM_PREFIX - 1) + +#ifdef HAVE_LINUX_XATTRS +#define MIGHT_NEED_RPRE (am_root <= 0) +#define RSYNC_PREFIX USER_PREFIX "rsync." +#else +#define MIGHT_NEED_RPRE am_root +#define RSYNC_PREFIX "rsync." +#endif +#define RPRE_LEN ((int)sizeof RSYNC_PREFIX - 1) + +#define XSTAT_SUFFIX "stat" +#define XSTAT_ATTR RSYNC_PREFIX "%" XSTAT_SUFFIX +#define XACC_ACL_SUFFIX "aacl" +#define XACC_ACL_ATTR RSYNC_PREFIX "%" XACC_ACL_SUFFIX +#define XDEF_ACL_SUFFIX "dacl" +#define XDEF_ACL_ATTR RSYNC_PREFIX "%" XDEF_ACL_SUFFIX + +typedef struct { + char *datum, *name; + size_t datum_len, name_len; + int num; +} rsync_xa; + +struct _rsync_xa_list; + +typedef struct _rsync_xa_list_ref { + struct _rsync_xa_list_ref *next; + int ndx; +} rsync_xa_list_ref; + +typedef struct _rsync_xa_list { + int ndx; + int64 key; + item_list xa_items; +} rsync_xa_list; + +static size_t namebuf_len = 0; +static char *namebuf = NULL; + +static const rsync_xa_list empty_xa_list = { + .xa_items = EMPTY_ITEM_LIST, +}; +static const item_list empty_xattr = EMPTY_ITEM_LIST; +static item_list rsync_xal_l = EMPTY_ITEM_LIST; +static struct hashtable *rsync_xal_h = NULL; + +static size_t prior_xattr_count = (size_t)-1; + +/* ------------------------------------------------------------------------- */ + +static void rsync_xal_free(item_list *xalp) +{ + size_t i; + rsync_xa *rxas = xalp->items; + + if (!xalp->malloced) + return; + + for (i = 0; i < xalp->count; i++) { + free(rxas[i].datum); + /*free(rxas[i].name);*/ + } + free(xalp->items); +} + +void free_xattr(stat_x *sxp) +{ + if (!sxp->xattr) + return; + rsync_xal_free(sxp->xattr); + free(sxp->xattr); + sxp->xattr = NULL; +} + +static int rsync_xal_compare_names(const void *x1, const void *x2) +{ + const rsync_xa *xa1 = x1; + const rsync_xa *xa2 = x2; + return strcmp(xa1->name, xa2->name); +} + +static ssize_t get_xattr_names(const char *fname) +{ + ssize_t list_len; + int64 arg; + + if (!namebuf) { + namebuf_len = 1024; + namebuf = new_array(char, namebuf_len); + } + + while (1) { + /* The length returned includes all the '\0' terminators. */ + list_len = sys_llistxattr(fname, namebuf, namebuf_len); + if (list_len >= 0) { + if ((size_t)list_len <= namebuf_len) + break; + } else if (errno == ENOTSUP) + return 0; + else if (errno != ERANGE) { + arg = namebuf_len; + got_error: + rsyserr(FERROR_XFER, errno, + "get_xattr_names: llistxattr(%s,%s) failed", + full_fname(fname), big_num(arg)); + return -1; + } + list_len = sys_llistxattr(fname, NULL, 0); + if (list_len < 0) { + arg = 0; + goto got_error; + } + if (namebuf_len) + free(namebuf); + namebuf_len = list_len + 1024; + namebuf = new_array(char, namebuf_len); + } + + return list_len; +} + +/* On entry, the *len_ptr parameter contains the size of the extra space we + * should allocate when we create a buffer for the data. On exit, it contains + * the length of the datum. */ +static char *get_xattr_data(const char *fname, const char *name, size_t *len_ptr, int no_missing_error) +{ + size_t datum_len = sys_lgetxattr(fname, name, NULL, 0); + size_t extra_len = *len_ptr; + char *ptr; + + *len_ptr = datum_len; + + if (datum_len == (size_t)-1) { + if (errno == ENOTSUP || no_missing_error) + return NULL; + rsyserr(FERROR_XFER, errno, + "get_xattr_data: lgetxattr(%s,\"%s\",0) failed", + full_fname(fname), name); + return NULL; + } + + if (!datum_len && !extra_len) + extra_len = 1; /* request non-zero amount of memory */ + if (SIZE_MAX - datum_len < extra_len) + overflow_exit("get_xattr_data"); + ptr = new_array(char, datum_len + extra_len); + + if (datum_len) { + size_t len = sys_lgetxattr(fname, name, ptr, datum_len); + if (len != datum_len) { + if (len == (size_t)-1) { + rsyserr(FERROR_XFER, errno, + "get_xattr_data: lgetxattr(%s,\"%s\",%ld) failed", + full_fname(fname), name, (long)datum_len); + } else { + rprintf(FERROR_XFER, + "get_xattr_data: lgetxattr(%s,\"%s\",%ld) returned %ld\n", + full_fname(fname), name, + (long)datum_len, (long)len); + } + free(ptr); + return NULL; + } + } + + return ptr; +} + +static int rsync_xal_get(const char *fname, item_list *xalp) +{ + ssize_t list_len, name_len; + size_t datum_len, name_offset; + char *name, *ptr; +#ifdef HAVE_LINUX_XATTRS + int user_only = am_sender ? 0 : !am_root; +#endif + rsync_xa *rxa; + int count; + + /* This puts the name list into the "namebuf" buffer. */ + if ((list_len = get_xattr_names(fname)) < 0) + return -1; + + for (name = namebuf; list_len > 0; name += name_len) { + name_len = strlen(name) + 1; + list_len -= name_len; + + if (saw_xattr_filter) { + if (name_is_excluded(name, NAME_IS_XATTR, ALL_FILTERS)) + continue; + } +#ifdef HAVE_LINUX_XATTRS + /* Choose between ignoring the system namespace or (non-root) ignoring any non-user namespace. */ + else if (user_only ? !HAS_PREFIX(name, USER_PREFIX) : HAS_PREFIX(name, SYSTEM_PREFIX)) + continue; +#endif + + /* No rsync.%FOO attributes are copied w/o 2 -X options. */ + if (name_len > RPRE_LEN && name[RPRE_LEN] == '%' && HAS_PREFIX(name, RSYNC_PREFIX)) { + if ((am_sender && preserve_xattrs < 2) + || (am_root < 0 + && (strcmp(name+RPRE_LEN+1, XSTAT_SUFFIX) == 0 + || strcmp(name+RPRE_LEN+1, XACC_ACL_SUFFIX) == 0 + || strcmp(name+RPRE_LEN+1, XDEF_ACL_SUFFIX) == 0))) + continue; + } + + datum_len = name_len; /* Pass extra size to get_xattr_data() */ + if (!(ptr = get_xattr_data(fname, name, &datum_len, 0))) + return -1; + + if (datum_len > MAX_FULL_DATUM) { + /* For large datums, we store a flag and a checksum. */ + name_offset = 1 + MAX_XATTR_DIGEST_LEN; + sum_init(xattr_sum_nni, checksum_seed); + sum_update(ptr, datum_len); + free(ptr); + + ptr = new_array(char, name_offset + name_len); + *ptr = XSTATE_ABBREV; + sum_end(ptr + 1); + } else + name_offset = datum_len; + + rxa = EXPAND_ITEM_LIST(xalp, rsync_xa, RSYNC_XAL_INITIAL); + rxa->name = ptr + name_offset; + memcpy(rxa->name, name, name_len); + rxa->datum = ptr; + rxa->name_len = name_len; + rxa->datum_len = datum_len; + } + count = xalp->count; + rxa = xalp->items; + if (count > 1) + qsort(rxa, count, sizeof (rsync_xa), rsync_xal_compare_names); + for (rxa += count-1; count; count--, rxa--) + rxa->num = count; + return 0; +} + +/* Read the xattr(s) for this filename. */ +int get_xattr(const char *fname, stat_x *sxp) +{ + sxp->xattr = new(item_list); + *sxp->xattr = empty_xattr; + + if (S_ISREG(sxp->st.st_mode) || S_ISDIR(sxp->st.st_mode)) { + /* Everyone supports this. */ + } else if (S_ISLNK(sxp->st.st_mode)) { +#ifndef NO_SYMLINK_XATTRS + if (!preserve_links) +#endif + return 0; + } else if (IS_SPECIAL(sxp->st.st_mode)) { +#ifndef NO_SPECIAL_XATTRS + if (!preserve_specials) +#endif + return 0; + } else if (IS_DEVICE(sxp->st.st_mode)) { +#ifndef NO_DEVICE_XATTRS + if (!preserve_devices) +#endif + return 0; + } else if (IS_MISSING_FILE(sxp->st)) + return 0; + + if (rsync_xal_get(fname, sxp->xattr) < 0) { + free_xattr(sxp); + return -1; + } + return 0; +} + +int copy_xattrs(const char *source, const char *dest) +{ + ssize_t list_len, name_len; + size_t datum_len; + char *name, *ptr; +#ifdef HAVE_LINUX_XATTRS + int user_only = am_sender ? 0 : am_root <= 0; +#endif + + /* This puts the name list into the "namebuf" buffer. */ + if ((list_len = get_xattr_names(source)) < 0) + return -1; + + for (name = namebuf; list_len > 0; name += name_len) { + name_len = strlen(name) + 1; + list_len -= name_len; + + if (saw_xattr_filter) { + if (name_is_excluded(name, NAME_IS_XATTR, ALL_FILTERS)) + continue; + } +#ifdef HAVE_LINUX_XATTRS + /* Choose between ignoring the system namespace or (non-root) ignoring any non-user namespace. */ + else if (user_only ? !HAS_PREFIX(name, USER_PREFIX) : HAS_PREFIX(name, SYSTEM_PREFIX)) + continue; +#endif + + datum_len = 0; + if (!(ptr = get_xattr_data(source, name, &datum_len, 0))) + return -1; + if (sys_lsetxattr(dest, name, ptr, datum_len) < 0) { + int save_errno = errno ? errno : EINVAL; + rsyserr(FERROR_XFER, errno, + "copy_xattrs: lsetxattr(%s,\"%s\") failed", + full_fname(dest), name); + errno = save_errno; + return -1; + } + free(ptr); + } + + return 0; +} + +static int64 xattr_lookup_hash(const item_list *xalp) +{ + const rsync_xa *rxas = xalp->items; + size_t i; + int64 key = hashlittle2(&xalp->count, sizeof xalp->count); + + for (i = 0; i < xalp->count; i++) { + key += hashlittle2(rxas[i].name, rxas[i].name_len); + if (rxas[i].datum_len > MAX_FULL_DATUM) + key += hashlittle2(rxas[i].datum, xattr_sum_len); + else + key += hashlittle2(rxas[i].datum, rxas[i].datum_len); + } + + return key; +} + +static int find_matching_xattr(const item_list *xalp) +{ + const struct ht_int64_node *node; + const rsync_xa_list_ref *ref; + int64 key; + + if (rsync_xal_h == NULL) + return -1; + + key = xattr_lookup_hash(xalp); + + node = hashtable_find(rsync_xal_h, key, NULL); + if (node == NULL) + return -1; + + if (node->data == NULL) + return -1; + + for (ref = node->data; ref != NULL; ref = ref->next) { + const rsync_xa_list *ptr = rsync_xal_l.items; + const rsync_xa *rxas1; + const rsync_xa *rxas2 = xalp->items; + size_t j; + + ptr += ref->ndx; + rxas1 = ptr->xa_items.items; + + /* Wrong number of elements? */ + if (ptr->xa_items.count != xalp->count) + continue; + /* any elements different? */ + for (j = 0; j < xalp->count; j++) { + if (rxas1[j].name_len != rxas2[j].name_len + || rxas1[j].datum_len != rxas2[j].datum_len + || strcmp(rxas1[j].name, rxas2[j].name)) + break; + if (rxas1[j].datum_len > MAX_FULL_DATUM) { + if (memcmp(rxas1[j].datum + 1, + rxas2[j].datum + 1, + xattr_sum_len) != 0) + break; + } else { + if (memcmp(rxas1[j].datum, rxas2[j].datum, + rxas2[j].datum_len)) + break; + } + } + /* no differences found. This is The One! */ + if (j == xalp->count) + return ref->ndx; + } + + return -1; +} + +/* Store *xalp on the end of rsync_xal_l */ +static int rsync_xal_store(item_list *xalp) +{ + struct ht_int64_node *node; + int ndx = rsync_xal_l.count; /* pre-incremented count */ + rsync_xa_list *new_list = EXPAND_ITEM_LIST(&rsync_xal_l, rsync_xa_list, RSYNC_XAL_LIST_INITIAL); + rsync_xa_list_ref *new_ref; + /* Since the following call starts a new list, we know it will hold the + * entire initial-count, not just enough space for one new item. */ + *new_list = empty_xa_list; + (void)EXPAND_ITEM_LIST(&new_list->xa_items, rsync_xa, xalp->count); + memcpy(new_list->xa_items.items, xalp->items, xalp->count * sizeof (rsync_xa)); + new_list->xa_items.count = xalp->count; + xalp->count = 0; + + new_list->ndx = ndx; + new_list->key = xattr_lookup_hash(&new_list->xa_items); + + if (rsync_xal_h == NULL) + rsync_xal_h = hashtable_create(512, HT_KEY64); + + new_ref = new0(rsync_xa_list_ref); + new_ref->ndx = ndx; + + node = hashtable_find(rsync_xal_h, new_list->key, new_ref); + if (node->data != (void*)new_ref) { + rsync_xa_list_ref *ref = node->data; + + while (ref != NULL) { + if (ref->next != NULL) { + ref = ref->next; + continue; + } + + ref->next = new_ref; + break; + } + } + + return ndx; +} + +/* Send the make_xattr()-generated xattr list for this flist entry. */ +int send_xattr(int f, stat_x *sxp) +{ + int ndx = find_matching_xattr(sxp->xattr); + + /* Send 0 (-1 + 1) to indicate that literal xattr data follows. */ + write_varint(f, ndx + 1); + + if (ndx < 0) { + rsync_xa *rxa; + int count = sxp->xattr->count; + write_varint(f, count); + for (rxa = sxp->xattr->items; count--; rxa++) { + size_t name_len = rxa->name_len; + const char *name = rxa->name; + /* Strip the rsync prefix from disguised namespaces. */ + if (name_len > RPRE_LEN +#ifdef HAVE_LINUX_XATTRS + && am_root < 0 +#endif + && name[RPRE_LEN] != '%' && HAS_PREFIX(name, RSYNC_PREFIX)) { + name += RPRE_LEN; + name_len -= RPRE_LEN; + } +#ifndef HAVE_LINUX_XATTRS + else { + /* Put everything else in the user namespace. */ + name_len += UPRE_LEN; + } +#endif + write_varint(f, name_len); + write_varint(f, rxa->datum_len); +#ifndef HAVE_LINUX_XATTRS + if (name_len > rxa->name_len) { + write_buf(f, USER_PREFIX, UPRE_LEN); + name_len -= UPRE_LEN; + } +#endif + write_buf(f, name, name_len); + if (rxa->datum_len > MAX_FULL_DATUM) + write_buf(f, rxa->datum + 1, xattr_sum_len); + else + write_bigbuf(f, rxa->datum, rxa->datum_len); + } + ndx = rsync_xal_store(sxp->xattr); /* adds item to rsync_xal_l */ + } + + return ndx; +} + +/* Return a flag indicating if we need to change a file's xattrs. If + * "find_all" is specified, also mark any abbreviated xattrs that we + * need so that send_xattr_request() can tell the sender about them. */ +int xattr_diff(struct file_struct *file, stat_x *sxp, int find_all) +{ + const rsync_xa_list *glst = rsync_xal_l.items; + const item_list *lst; + rsync_xa *snd_rxa, *rec_rxa; + int snd_cnt, rec_cnt; + int cmp, same, xattrs_equal = 1; + + if (sxp && XATTR_READY(*sxp)) { + rec_rxa = sxp->xattr->items; + rec_cnt = sxp->xattr->count; + } else { + rec_rxa = NULL; + rec_cnt = 0; + } + + if (F_XATTR(file) >= 0) { + glst += F_XATTR(file); + lst = &glst->xa_items; + } else + lst = &empty_xattr; + + snd_rxa = lst->items; + snd_cnt = lst->count; + + /* If the count of the sender's xattrs is different from our + * (receiver's) xattrs, the lists are not the same. */ + if (snd_cnt != rec_cnt) { + if (!find_all) + return 1; + xattrs_equal = 0; + } + + while (snd_cnt) { + cmp = rec_cnt ? strcmp(snd_rxa->name, rec_rxa->name) : -1; + if (cmp > 0) + same = 0; + else if (snd_rxa->datum_len > MAX_FULL_DATUM) { + same = cmp == 0 && snd_rxa->datum_len == rec_rxa->datum_len + && memcmp(snd_rxa->datum + 1, rec_rxa->datum + 1, + xattr_sum_len) == 0; + /* Flag unrequested items that we need. */ + if (!same && find_all && snd_rxa->datum[0] == XSTATE_ABBREV) + snd_rxa->datum[0] = XSTATE_TODO; + } else { + same = cmp == 0 && snd_rxa->datum_len == rec_rxa->datum_len + && memcmp(snd_rxa->datum, rec_rxa->datum, + snd_rxa->datum_len) == 0; + } + if (!same) { + if (!find_all) + return 1; + xattrs_equal = 0; + } + + if (cmp <= 0) { + snd_rxa++; + snd_cnt--; + } + if (cmp >= 0) { + rec_rxa++; + rec_cnt--; + } + } + + if (rec_cnt) + xattrs_equal = 0; + + return !xattrs_equal; +} + +/* When called by the generator (with a NULL fname), this tells the sender + * all the abbreviated xattr values we need. When called by the sender + * (with a non-NULL fname), we send all the extra xattr data it needs. + * The generator may also call with f_out < 0 to just change all the + * XSTATE_ABBREV states into XSTATE_DONE. */ +void send_xattr_request(const char *fname, struct file_struct *file, int f_out) +{ + const rsync_xa_list *glst = rsync_xal_l.items; + const item_list *lst; + int cnt, prior_req = 0; + rsync_xa *rxa; + + glst += F_XATTR(file); + lst = &glst->xa_items; + + for (rxa = lst->items, cnt = lst->count; cnt--; rxa++) { + if (rxa->datum_len <= MAX_FULL_DATUM) + continue; + switch (rxa->datum[0]) { + case XSTATE_ABBREV: + /* Items left abbreviated matched the sender's checksum, so + * the receiver will cache the local data for future use. */ + if (am_generator) + rxa->datum[0] = XSTATE_DONE; + continue; + case XSTATE_TODO: + assert(f_out >= 0); + break; + default: + continue; + } + + /* Flag that we handled this abbreviated item. */ + rxa->datum[0] = XSTATE_DONE; + + write_varint(f_out, rxa->num - prior_req); + prior_req = rxa->num; + + if (fname) { + size_t len = 0; + char *ptr; + + /* Re-read the long datum. */ + if (!(ptr = get_xattr_data(fname, rxa->name, &len, 0))) { + rprintf(FERROR_XFER, "failed to re-read xattr %s for %s\n", rxa->name, fname); + write_varint(f_out, 0); + continue; + } + + write_varint(f_out, len); /* length might have changed! */ + write_bigbuf(f_out, ptr, len); + free(ptr); + } + } + + if (f_out >= 0) + write_byte(f_out, 0); /* end the list */ +} + +/* When called by the sender, read the request from the generator and mark + * any needed xattrs with a flag that lets us know they need to be sent to + * the receiver. When called by the receiver, reads the sent data and + * stores it in place of its checksum. */ +int recv_xattr_request(struct file_struct *file, int f_in) +{ + const rsync_xa_list *glst = rsync_xal_l.items; + const item_list *lst; + char *old_datum, *name; + rsync_xa *rxa; + int rel_pos, cnt, num, got_xattr_data = 0; + + if (F_XATTR(file) < 0) { + rprintf(FERROR, "recv_xattr_request: internal data error!\n"); + exit_cleanup(RERR_PROTOCOL); + } + glst += F_XATTR(file); + lst = &glst->xa_items; + + cnt = lst->count; + rxa = lst->items; + num = 0; + while ((rel_pos = read_varint(f_in)) != 0) { + num += rel_pos; + if (am_sender) { + /* The sender-related num values are only in order on the sender. + * We use that order here to scan forward or backward as needed. */ + if (rel_pos < 0) { + while (cnt < (int)lst->count && rxa->num > num) { + rxa--; + cnt++; + } + } else { + while (cnt > 1 && rxa->num < num) { + rxa++; + cnt--; + } + } + } else { + int j; + /* The receiving side has no known num order, so we just scan + * forward (w/wrap) and hope that the next value is near by. */ + for (j = lst->count; j > 1 && rxa->num != num; j--) { + if (--cnt) + rxa++; + else { + cnt = lst->count; + rxa = lst->items; + } + } + } + if (!cnt || rxa->num != num) { + rprintf(FERROR, "[%s] could not find xattr #%d for %s\n", + who_am_i(), num, f_name(file, NULL)); + exit_cleanup(RERR_PROTOCOL); + } + if (!XATTR_ABBREV(*rxa) || rxa->datum[0] != XSTATE_ABBREV) { + rprintf(FERROR, "[%s] internal abbrev error on %s (%s, len=%ld)!\n", + who_am_i(), f_name(file, NULL), rxa->name, (long)rxa->datum_len); + exit_cleanup(RERR_PROTOCOL); + } + + if (am_sender) { + rxa->datum[0] = XSTATE_TODO; + continue; + } + + old_datum = rxa->datum; + rxa->datum_len = read_varint(f_in); + + if (SIZE_MAX - rxa->name_len < rxa->datum_len) + overflow_exit("recv_xattr_request"); + rxa->datum = new_array(char, rxa->datum_len + rxa->name_len); + name = rxa->datum + rxa->datum_len; + memcpy(name, rxa->name, rxa->name_len); + rxa->name = name; + free(old_datum); + read_buf(f_in, rxa->datum, rxa->datum_len); + got_xattr_data = 1; + } + + return got_xattr_data; +} + +/* ------------------------------------------------------------------------- */ + +/* receive and build the rsync_xattr_lists */ +void receive_xattr(int f, struct file_struct *file) +{ + static item_list temp_xattr = EMPTY_ITEM_LIST; + int count, num; +#ifdef HAVE_LINUX_XATTRS + int need_sort = 0; +#else + int need_sort = 1; +#endif + int ndx = read_varint(f); + + if (ndx < 0 || (size_t)ndx > rsync_xal_l.count) { + rprintf(FERROR, "receive_xattr: xa index %d out of" + " range for %s\n", ndx, f_name(file, NULL)); + exit_cleanup(RERR_STREAMIO); + } + + if (ndx != 0) { + F_XATTR(file) = ndx - 1; + return; + } + + if ((count = read_varint(f)) != 0) { + (void)EXPAND_ITEM_LIST(&temp_xattr, rsync_xa, count); + temp_xattr.count = 0; + } + + for (num = 1; num <= count; num++) { + char *ptr, *name; + rsync_xa *rxa; + size_t name_len = read_varint(f); + size_t datum_len = read_varint(f); + size_t dget_len = datum_len > MAX_FULL_DATUM ? 1 + (size_t)xattr_sum_len : datum_len; + size_t extra_len = MIGHT_NEED_RPRE ? RPRE_LEN : 0; + if (SIZE_MAX - dget_len < extra_len || SIZE_MAX - dget_len - extra_len < name_len) + overflow_exit("receive_xattr"); + ptr = new_array(char, dget_len + extra_len + name_len); + name = ptr + dget_len + extra_len; + read_buf(f, name, name_len); + if (name_len < 1 || name[name_len-1] != '\0') { + rprintf(FERROR, "Invalid xattr name received (missing trailing \\0).\n"); + exit_cleanup(RERR_FILEIO); + } + if (dget_len == datum_len) + read_buf(f, ptr, dget_len); + else { + *ptr = XSTATE_ABBREV; + read_buf(f, ptr + 1, xattr_sum_len); + } + + if (saw_xattr_filter) { + if (name_is_excluded(name, NAME_IS_XATTR, ALL_FILTERS)) { + free(ptr); + continue; + } + } +#ifdef HAVE_LINUX_XATTRS + /* Non-root can only save the user namespace. */ + if (am_root <= 0 && !HAS_PREFIX(name, USER_PREFIX)) { + if (!am_root && !saw_xattr_filter) { + free(ptr); + continue; + } + name -= RPRE_LEN; + name_len += RPRE_LEN; + memcpy(name, RSYNC_PREFIX, RPRE_LEN); + need_sort = 1; + } +#else + /* This OS only has a user namespace, so we either + * strip the user prefix, or we put a non-user + * namespace inside our rsync hierarchy. */ + if (HAS_PREFIX(name, USER_PREFIX)) { + name += UPRE_LEN; + name_len -= UPRE_LEN; + } else if (am_root) { + name -= RPRE_LEN; + name_len += RPRE_LEN; + memcpy(name, RSYNC_PREFIX, RPRE_LEN); + } else { + free(ptr); + continue; + } +#endif + /* No rsync.%FOO attributes are copied w/o 2 -X options. */ + if (preserve_xattrs < 2 && name_len > RPRE_LEN + && name[RPRE_LEN] == '%' && HAS_PREFIX(name, RSYNC_PREFIX)) { + free(ptr); + continue; + } + + rxa = EXPAND_ITEM_LIST(&temp_xattr, rsync_xa, 1); + rxa->name = name; + rxa->datum = ptr; + rxa->name_len = name_len; + rxa->datum_len = datum_len; + rxa->num = num; + } + + if (need_sort && count > 1) + qsort(temp_xattr.items, count, sizeof (rsync_xa), rsync_xal_compare_names); + + ndx = rsync_xal_store(&temp_xattr); /* adds item to rsync_xal_l */ + + F_XATTR(file) = ndx; +} + +/* Turn the xattr data in stat_x into cached xattr data, setting the index + * values in the file struct. */ +void cache_tmp_xattr(struct file_struct *file, stat_x *sxp) +{ + int ndx; + + if (!sxp->xattr) + return; + + if (prior_xattr_count == (size_t)-1) + prior_xattr_count = rsync_xal_l.count; + ndx = find_matching_xattr(sxp->xattr); + if (ndx < 0) + rsync_xal_store(sxp->xattr); /* adds item to rsync_xal_l */ + + F_XATTR(file) = ndx; +} + +void uncache_tmp_xattrs(void) +{ + if (prior_xattr_count != (size_t)-1) { + rsync_xa_list *xa_list_item = rsync_xal_l.items; + rsync_xa_list *xa_list_start = xa_list_item + prior_xattr_count; + xa_list_item += rsync_xal_l.count; + rsync_xal_l.count = prior_xattr_count; + while (xa_list_item-- > xa_list_start) { + struct ht_int64_node *node; + rsync_xa_list_ref *ref; + + rsync_xal_free(&xa_list_item->xa_items); + + if (rsync_xal_h == NULL) + continue; + + node = hashtable_find(rsync_xal_h, xa_list_item->key, NULL); + if (node == NULL) + continue; + + if (node->data == NULL) + continue; + + ref = node->data; + if (xa_list_item->ndx == ref->ndx) { + /* xa_list_item is the first in the list. */ + node->data = ref->next; + free(ref); + continue; + } + + while (1) { + rsync_xa_list_ref *next = ref->next; + if (next == NULL) + break; + if (xa_list_item->ndx == next->ndx) { + ref->next = next->next; + free(next); + break; + } + ref = next; + } + } + prior_xattr_count = (size_t)-1; + } +} + +static int rsync_xal_set(const char *fname, item_list *xalp, + const char *fnamecmp, stat_x *sxp) +{ + rsync_xa *rxas = xalp->items; + ssize_t list_len; + size_t i, len; + char *name, *ptr, sum[MAX_XATTR_DIGEST_LEN]; +#ifdef HAVE_LINUX_XATTRS + int user_only = am_root <= 0; +#endif + size_t name_len; + int ret = 0; + + /* This puts the current name list into the "namebuf" buffer. */ + if ((list_len = get_xattr_names(fname)) < 0) + return -1; + + for (i = 0; i < xalp->count; i++) { + name = rxas[i].name; + + if (XATTR_ABBREV(rxas[i])) { + /* See if the fnamecmp version is identical. */ + len = name_len = rxas[i].name_len; + if ((ptr = get_xattr_data(fnamecmp, name, &len, 1)) == NULL) { + still_abbrev: + if (am_generator) + continue; + rprintf(FERROR, "Missing abbreviated xattr value, %s, for %s\n", + rxas[i].name, full_fname(fname)); + ret = -1; + continue; + } + if (len != rxas[i].datum_len) { + free(ptr); + goto still_abbrev; + } + + sum_init(xattr_sum_nni, checksum_seed); + sum_update(ptr, len); + sum_end(sum); + if (memcmp(sum, rxas[i].datum + 1, xattr_sum_len) != 0) { + free(ptr); + goto still_abbrev; + } + + if (fname == fnamecmp) + ; /* Value is already set when identical */ + else if (sys_lsetxattr(fname, name, ptr, len) < 0) { + rsyserr(FERROR_XFER, errno, + "rsync_xal_set: lsetxattr(%s,\"%s\") failed", + full_fname(fname), name); + ret = -1; + } else /* make sure caller sets mtime */ + sxp->st.st_mtime = (time_t)-1; + + if (am_generator) { /* generator items stay abbreviated */ + free(ptr); + continue; + } + + memcpy(ptr + len, name, name_len); + free(rxas[i].datum); + + rxas[i].name = name = ptr + len; + rxas[i].datum = ptr; + continue; + } + + if (sys_lsetxattr(fname, name, rxas[i].datum, rxas[i].datum_len) < 0) { + rsyserr(FERROR_XFER, errno, + "rsync_xal_set: lsetxattr(%s,\"%s\") failed", + full_fname(fname), name); + ret = -1; + } else /* make sure caller sets mtime */ + sxp->st.st_mtime = (time_t)-1; + } + + /* Remove any extraneous names. */ + for (name = namebuf; list_len > 0; name += name_len) { + name_len = strlen(name) + 1; + list_len -= name_len; + + if (saw_xattr_filter) { + if (name_is_excluded(name, NAME_IS_XATTR, ALL_FILTERS)) + continue; + } +#ifdef HAVE_LINUX_XATTRS + /* Choose between ignoring the system namespace or (non-root) ignoring any non-user namespace. */ + else if (user_only ? !HAS_PREFIX(name, USER_PREFIX) : HAS_PREFIX(name, SYSTEM_PREFIX)) + continue; +#endif + if (am_root < 0 && name_len > RPRE_LEN && name[RPRE_LEN] == '%' && strcmp(name, XSTAT_ATTR) == 0) + continue; + + for (i = 0; i < xalp->count; i++) { + if (strcmp(name, rxas[i].name) == 0) + break; + } + if (i == xalp->count) { + if (sys_lremovexattr(fname, name) < 0) { + rsyserr(FERROR_XFER, errno, + "rsync_xal_set: lremovexattr(%s,\"%s\") failed", + full_fname(fname), name); + ret = -1; + } else /* make sure caller sets mtime */ + sxp->st.st_mtime = (time_t)-1; + } + } + + return ret; +} + +/* Set extended attributes on indicated filename. */ +int set_xattr(const char *fname, const struct file_struct *file, const char *fnamecmp, stat_x *sxp) +{ + rsync_xa_list *glst = rsync_xal_l.items; + item_list *lst; + int ndx, added_write_perm = 0; + + if (dry_run) + return 1; /* FIXME: --dry-run needs to compute this value */ + + if (read_only || list_only) { + errno = EROFS; + return -1; + } + +#ifdef NO_SPECIAL_XATTRS + if (IS_SPECIAL(sxp->st.st_mode)) { + errno = ENOTSUP; + return -1; + } +#endif +#ifdef NO_DEVICE_XATTRS + if (IS_DEVICE(sxp->st.st_mode)) { + errno = ENOTSUP; + return -1; + } +#endif +#ifdef NO_SYMLINK_XATTRS + if (S_ISLNK(sxp->st.st_mode)) { + errno = ENOTSUP; + return -1; + } +#endif + + /* If the target file lacks write permission, we try to add it + * temporarily so we can change the extended attributes. */ + if (!am_root +#ifdef SUPPORT_LINKS + && !S_ISLNK(sxp->st.st_mode) +#endif + && access(fname, W_OK) < 0 + && do_chmod(fname, (sxp->st.st_mode & CHMOD_BITS) | S_IWUSR) == 0) + added_write_perm = 1; + + ndx = F_XATTR(file); + glst += ndx; + lst = &glst->xa_items; + int return_value = rsync_xal_set(fname, lst, fnamecmp, sxp); + if (added_write_perm) /* remove the temporary write permission */ + do_chmod(fname, sxp->st.st_mode); + return return_value; +} + +#ifdef SUPPORT_ACLS +char *get_xattr_acl(const char *fname, int is_access_acl, size_t *len_p) +{ + const char *name = is_access_acl ? XACC_ACL_ATTR : XDEF_ACL_ATTR; + *len_p = 0; /* no extra data alloc needed from get_xattr_data() */ + return get_xattr_data(fname, name, len_p, 1); +} + +int set_xattr_acl(const char *fname, int is_access_acl, const char *buf, size_t buf_len) +{ + const char *name = is_access_acl ? XACC_ACL_ATTR : XDEF_ACL_ATTR; + if (sys_lsetxattr(fname, name, buf, buf_len) < 0) { + rsyserr(FERROR_XFER, errno, + "set_xattr_acl: lsetxattr(%s,\"%s\") failed", + full_fname(fname), name); + return -1; + } + return 0; +} + +int del_def_xattr_acl(const char *fname) +{ + return sys_lremovexattr(fname, XDEF_ACL_ATTR); +} +#endif + +int get_stat_xattr(const char *fname, int fd, STRUCT_STAT *fst, STRUCT_STAT *xst) +{ + unsigned int mode; + int rdev_major, rdev_minor, uid, gid, len; + char buf[256]; + + if (am_root >= 0 || IS_DEVICE(fst->st_mode) || IS_SPECIAL(fst->st_mode)) + return -1; + + if (xst) + *xst = *fst; + else + xst = fst; + if (fname) { + fd = -1; + len = sys_lgetxattr(fname, XSTAT_ATTR, buf, sizeof buf - 1); + } else { + fname = "fd"; + len = sys_fgetxattr(fd, XSTAT_ATTR, buf, sizeof buf - 1); + } + if (len >= (int)sizeof buf) { + len = -1; + errno = ERANGE; + } + if (len < 0) { + if (errno == ENOTSUP || errno == ENOATTR) + return -1; + if (errno == EPERM && S_ISLNK(fst->st_mode)) { + xst->st_uid = 0; + xst->st_gid = 0; + return 0; + } + rsyserr(FERROR_XFER, errno, "failed to read xattr %s for %s", + XSTAT_ATTR, full_fname(fname)); + return -1; + } + buf[len] = '\0'; + + if (sscanf(buf, "%o %d,%d %d:%d", + &mode, &rdev_major, &rdev_minor, &uid, &gid) != 5) { + rprintf(FERROR, "Corrupt %s xattr attached to %s: \"%s\"\n", + XSTAT_ATTR, full_fname(fname), buf); + exit_cleanup(RERR_FILEIO); + } + + xst->st_mode = from_wire_mode(mode); + xst->st_rdev = MAKEDEV(rdev_major, rdev_minor); + xst->st_uid = uid; + xst->st_gid = gid; + + return 0; +} + +int set_stat_xattr(const char *fname, struct file_struct *file, mode_t new_mode) +{ + STRUCT_STAT fst, xst; + dev_t rdev; + mode_t mode, fmode; + + if (dry_run) + return 0; + + if (read_only || list_only) { + rsyserr(FERROR_XFER, EROFS, "failed to write xattr %s for %s", + XSTAT_ATTR, full_fname(fname)); + return -1; + } + + if (x_lstat(fname, &fst, &xst) < 0) { + rsyserr(FERROR_XFER, errno, "failed to re-stat %s", + full_fname(fname)); + return -1; + } + + fst.st_mode &= (_S_IFMT | CHMOD_BITS); + fmode = new_mode & (_S_IFMT | CHMOD_BITS); + + if (IS_DEVICE(fmode)) { + uint32 *devp = F_RDEV_P(file); + rdev = MAKEDEV(DEV_MAJOR(devp), DEV_MINOR(devp)); + } else + rdev = 0; + + /* Dump the special permissions and enable full owner access. */ + mode = (fst.st_mode & _S_IFMT) | (fmode & ACCESSPERMS) + | (S_ISDIR(fst.st_mode) ? 0700 : 0600); + if (fst.st_mode != mode) + do_chmod(fname, mode); + if (!IS_DEVICE(fst.st_mode)) + fst.st_rdev = 0; /* just in case */ + + if (mode == fmode && fst.st_rdev == rdev + && fst.st_uid == F_OWNER(file) && fst.st_gid == F_GROUP(file)) { + /* xst.st_mode will be 0 if there's no current stat xattr */ + if (xst.st_mode && sys_lremovexattr(fname, XSTAT_ATTR) < 0) { + rsyserr(FERROR_XFER, errno, + "delete of stat xattr failed for %s", + full_fname(fname)); + return -1; + } + return 0; + } + + if (xst.st_mode != fmode || xst.st_rdev != rdev + || xst.st_uid != F_OWNER(file) || xst.st_gid != F_GROUP(file)) { + char buf[256]; + int len = snprintf(buf, sizeof buf, "%o %u,%u %u:%u", + to_wire_mode(fmode), + (int)major(rdev), (int)minor(rdev), + F_OWNER(file), F_GROUP(file)); + if (sys_lsetxattr(fname, XSTAT_ATTR, buf, len) < 0) { + if (errno == EPERM && S_ISLNK(fst.st_mode)) + return 0; + rsyserr(FERROR_XFER, errno, + "failed to write xattr %s for %s", + XSTAT_ATTR, full_fname(fname)); + return -1; + } + } + + return 0; +} + +int x_stat(const char *fname, STRUCT_STAT *fst, STRUCT_STAT *xst) +{ + int ret = do_stat(fname, fst); + if ((ret < 0 || get_stat_xattr(fname, -1, fst, xst) < 0) && xst) + xst->st_mode = 0; + return ret; +} + +int x_lstat(const char *fname, STRUCT_STAT *fst, STRUCT_STAT *xst) +{ + int ret = do_lstat(fname, fst); + if ((ret < 0 || get_stat_xattr(fname, -1, fst, xst) < 0) && xst) + xst->st_mode = 0; + return ret; +} + +int x_fstat(int fd, STRUCT_STAT *fst, STRUCT_STAT *xst) +{ + int ret = do_fstat(fd, fst); + if ((ret < 0 || get_stat_xattr(NULL, fd, fst, xst) < 0) && xst) + xst->st_mode = 0; + return ret; +} + +#endif /* SUPPORT_XATTRS */ |