xbps/lib/package_remove.c
Juan RP 2711b07b77 Fix package files removal with only read bit set.
The previous code was checking incorrectly if the file had the write
bit set, and this is wrong because a package could have files with
only the read bit set (0444).
2014-09-28 13:33:15 +02:00

392 lines
11 KiB
C

/*-
* Copyright (c) 2009-2014 Juan Romero Pardines.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <stdio.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <dirent.h>
#include <libgen.h>
#include <fcntl.h>
#include <unistd.h>
#include "xbps_api_impl.h"
static bool
check_remove_pkg_files(struct xbps_handle *xhp,
xbps_dictionary_t pkgd, const char *pkgver, uid_t euid)
{
struct stat st;
xbps_array_t array;
xbps_object_iterator_t iter;
xbps_object_t obj;
const char *objs[] = { "files", "conf_files", "links", "dirs" };
const char *file;
char path[PATH_MAX];
bool fail = false;
for (uint8_t i = 0; i < __arraycount(objs); i++) {
array = xbps_dictionary_get(pkgd, objs[i]);
if (array == NULL || xbps_array_count(array) == 0)
continue;
iter = xbps_array_iter_from_dict(pkgd, objs[i]);
if (iter == NULL)
continue;
while ((obj = xbps_object_iterator_next(iter))) {
xbps_dictionary_get_cstring_nocopy(obj, "file", &file);
snprintf(path, sizeof(path), "%s/%s", xhp->rootdir, file);
/*
* Check if effective user ID owns the file; this is
* enough to ensure the user has write permissions
* on the directory.
*/
if (!lstat(path, &st) && euid == st.st_uid) {
/* success */
continue;
}
if (errno != ENOENT) {
/*
* only bail out if something else than ENOENT
* is returned.
*/
int rv = errno;
if (rv == 0) {
/* lstat succeeds but euid != uid */
rv = EPERM;
}
fail = true;
xbps_set_cb_state(xhp, XBPS_STATE_REMOVE_FILE_FAIL,
errno, pkgver,
"%s: cannot remove `%s': %s",
pkgver, file, strerror(rv));
}
}
xbps_object_iterator_release(iter);
}
return fail;
}
static int
remove_pkg_files(struct xbps_handle *xhp,
xbps_dictionary_t dict,
const char *key,
const char *pkgver)
{
xbps_array_t array;
xbps_object_iterator_t iter;
xbps_object_t obj;
const char *file, *sha256, *curobj = NULL;
/* These are symlinks in Void and must not be removed */
const char *basesymlinks[] = {
"/bin",
"/sbin",
"/lib",
"/lib32",
"/lib64",
"/usr/lib32",
"/usr/lib64",
"/var/run",
};
char path[PATH_MAX];
int rv = 0;
bool found;
assert(xbps_object_type(dict) == XBPS_TYPE_DICTIONARY);
assert(key != NULL);
array = xbps_dictionary_get(dict, key);
if (xbps_array_count(array) == 0)
return 0;
iter = xbps_array_iter_from_dict(dict, key);
if (iter == NULL)
return ENOMEM;
if (strcmp(key, "files") == 0)
curobj = "file";
else if (strcmp(key, "conf_files") == 0)
curobj = "configuration file";
else if (strcmp(key, "links") == 0)
curobj = "link";
else if (strcmp(key, "dirs") == 0)
curobj = "directory";
xbps_object_iterator_reset(iter);
while ((obj = xbps_object_iterator_next(iter))) {
xbps_dictionary_get_cstring_nocopy(obj, "file", &file);
snprintf(path, sizeof(path), "%s/%s", xhp->rootdir, file);
if ((strcmp(key, "files") == 0) ||
(strcmp(key, "conf_files") == 0)) {
/*
* Check SHA256 hash in regular files and
* configuration files.
*/
xbps_dictionary_get_cstring_nocopy(obj,
"sha256", &sha256);
rv = xbps_file_hash_check(path, sha256);
if (rv == ENOENT) {
/* missing file, ignore it */
xbps_set_cb_state(xhp,
XBPS_STATE_REMOVE_FILE_HASH_FAIL,
rv, pkgver,
"%s: failed to check hash for %s `%s': %s",
pkgver, curobj, file, strerror(rv));
rv = 0;
continue;
} else if (rv == ERANGE) {
rv = 0;
if ((xhp->flags &
XBPS_FLAG_FORCE_REMOVE_FILES) == 0) {
xbps_set_cb_state(xhp,
XBPS_STATE_REMOVE_FILE_HASH_FAIL,
0, pkgver,
"%s: %s `%s' SHA256 mismatch, "
"preserving file", pkgver,
curobj, file);
continue;
} else {
xbps_set_cb_state(xhp,
XBPS_STATE_REMOVE_FILE_HASH_FAIL,
0, pkgver,
"%s: %s `%s' SHA256 mismatch, "
"forcing removal", pkgver,
curobj, file);
}
} else if (rv != 0 && rv != ERANGE) {
xbps_set_cb_state(xhp,
XBPS_STATE_REMOVE_FILE_HASH_FAIL,
rv, pkgver,
"%s: [remove] failed to check hash for "
"%s `%s': %s", pkgver, curobj, file,
strerror(rv));
break;
}
}
/*
* Make sure to not remove any symlink of root directory.
*/
found = false;
for (uint8_t i = 0; i < __arraycount(basesymlinks); i++) {
if (strcmp(file, basesymlinks[i]) == 0) {
found = true;
xbps_dbg_printf(xhp, "[remove] %s ignoring "
"%s removal\n", pkgver, file);
break;
}
}
if (found) {
continue;
}
/*
* Remove the object if possible.
*/
if (remove(path) == -1) {
xbps_set_cb_state(xhp, XBPS_STATE_REMOVE_FILE_FAIL,
errno, pkgver,
"%s: failed to remove %s `%s': %s", pkgver,
curobj, file, strerror(errno));
} else {
/* success */
xbps_set_cb_state(xhp, XBPS_STATE_REMOVE_FILE,
0, pkgver, "Removed %s `%s'", curobj, file);
}
}
xbps_object_iterator_release(iter);
return rv;
}
int HIDDEN
xbps_remove_pkg(struct xbps_handle *xhp, const char *pkgver, bool update)
{
xbps_dictionary_t pkgd = NULL, pkgfilesd = NULL;
char *pkgname, metafile[PATH_MAX];
int rv = 0;
pkg_state_t state = 0;
uid_t euid;
assert(xhp);
assert(pkgver);
pkgname = xbps_pkg_name(pkgver);
assert(pkgname);
euid = geteuid();
if ((pkgd = xbps_pkgdb_get_pkg(xhp, pkgname)) == NULL) {
rv = errno;
xbps_dbg_printf(xhp, "[remove] cannot find %s in pkgdb: %s\n",
pkgver, strerror(rv));
goto out;
}
if ((rv = xbps_pkg_state_dictionary(pkgd, &state)) != 0) {
xbps_dbg_printf(xhp, "[remove] cannot find %s in pkgdb: %s\n",
pkgver, strerror(rv));
goto out;
}
xbps_dbg_printf(xhp, "attempting to remove %s state %d\n", pkgver, state);
if (!update)
xbps_set_cb_state(xhp, XBPS_STATE_REMOVE, 0, pkgver, NULL);
if (chdir(xhp->rootdir) == -1) {
rv = errno;
xbps_set_cb_state(xhp, XBPS_STATE_REMOVE_FAIL,
rv, pkgver,
"%s: [remove] failed to chdir to rootdir `%s': %s",
pkgver, xhp->rootdir, strerror(rv));
goto out;
}
/* internalize pkg files dictionary from metadir */
snprintf(metafile, sizeof(metafile), "%s/.%s-files.plist", xhp->metadir, pkgname);
pkgfilesd = xbps_dictionary_internalize_from_file(metafile);
if (pkgfilesd == NULL)
xbps_dbg_printf(xhp, "WARNING: metaplist for %s "
"doesn't exist!\n", pkgver);
/* If package was "half-removed", remove it fully. */
if (state == XBPS_PKG_STATE_HALF_REMOVED)
goto purge;
/*
* Run the pre remove action and show pre-remove message if exists.
*/
rv = xbps_pkg_exec_script(xhp, pkgd, "remove-script", "pre", update);
if (rv != 0) {
xbps_set_cb_state(xhp, XBPS_STATE_REMOVE_FAIL,
errno, pkgver,
"%s: [remove] REMOVE script failed to "
"execute pre ACTION: %s",
pkgver, strerror(rv));
goto out;
}
/* show remove-msg if exists */
if ((rv = xbps_cb_message(xhp, pkgd, "remove-msg")) != 0)
goto out;
/*
* If updating a package, we just need to execute the current
* pre-remove action target and we are done. Its files will be
* overwritten later in unpack phase.
*/
if (update) {
free(pkgname);
return 0;
}
if (pkgfilesd) {
/*
* Do the removal in 2 phases:
* 1- check if user has enough perms to remove all entries
* 2- perform removal
*/
if (check_remove_pkg_files(xhp, pkgfilesd, pkgver, euid)) {
rv = EPERM;
goto out;
}
/* Remove regular files */
if ((rv = remove_pkg_files(xhp, pkgfilesd, "files", pkgver)) != 0)
goto out;
/* Remove configuration files */
if ((rv = remove_pkg_files(xhp, pkgfilesd, "conf_files", pkgver)) != 0)
goto out;
/* Remove links */
if ((rv = remove_pkg_files(xhp, pkgfilesd, "links", pkgver)) != 0)
goto out;
/* Remove dirs */
if ((rv = remove_pkg_files(xhp, pkgfilesd, "dirs", pkgver)) != 0)
goto out;
}
/*
* Execute the post REMOVE action if file exists and we aren't
* updating the package.
*/
rv = xbps_pkg_exec_script(xhp, pkgd, "remove-script", "post", false);
if (rv != 0) {
xbps_set_cb_state(xhp, XBPS_STATE_REMOVE_FAIL,
rv, pkgver,
"%s: [remove] REMOVE script failed to execute "
"post ACTION: %s", pkgver, strerror(rv));
goto out;
}
/*
* Set package state to "half-removed".
*/
rv = xbps_set_pkg_state_installed(xhp, pkgver,
XBPS_PKG_STATE_HALF_REMOVED);
if (rv != 0) {
xbps_set_cb_state(xhp, XBPS_STATE_REMOVE_FAIL,
rv, pkgver,
"%s: [remove] failed to set state to half-removed: %s",
pkgver, strerror(rv));
goto out;
}
purge:
/*
* Execute the purge REMOVE action if file exists.
*/
rv = xbps_pkg_exec_script(xhp, pkgd, "remove-script", "purge", false);
if (rv != 0) {
xbps_set_cb_state(xhp, XBPS_STATE_REMOVE_FAIL,
rv, pkgver,
"%s: REMOVE script failed to execute "
"purge ACTION: %s", pkgver, strerror(rv));
goto out;
}
/*
* Remove package metadata plist.
*/
if (remove(metafile) == -1) {
if (errno != ENOENT) {
xbps_set_cb_state(xhp, XBPS_STATE_REMOVE_FAIL,
rv, pkgver,
"%s: failed to remove metadata file: %s",
pkgver, strerror(errno));
}
}
/*
* Unregister package from pkgdb.
*/
xbps_dictionary_remove(xhp->pkgdb, pkgname);
xbps_dbg_printf(xhp, "[remove] unregister %s returned %d\n", pkgver, rv);
xbps_set_cb_state(xhp, XBPS_STATE_REMOVE_DONE, 0, pkgver, NULL);
out:
if (pkgname != NULL)
free(pkgname);
if (rv != 0) {
xbps_set_cb_state(xhp, XBPS_STATE_REMOVE_FAIL, rv, pkgver,
"%s: failed to remove package: %s", pkgver, strerror(rv));
}
return rv;
}