replicant-frameworks_native/cmds/installd/utils.cpp
Jeff Sharkey e363724230 Command to move private app data between volumes.
New "mvuserdata" command will move all private app data from one
volume UUID to another.  It leverages the existing "cp" toybox
command to do the heavy lifting for all known users, preserving
details like timestamps and permissions.  It invokes restorecon()
to correctly label the new location when the copy is finished.

Changes installd to no longer drop capabilities, so we run as root
again.  This also allows us to exec "cp" with CAP_DAC_OVERRIDE and
CAP_FOWNER still in effect.

Bug: 19993667
Change-Id: I1f407a7c4a1af97ca5afc27b04eb16b4936cbdef
2015-04-10 00:21:35 -07:00

1155 lines
35 KiB
C++

/*
** Copyright 2008, The Android Open Source Project
**
** Licensed under the Apache License, Version 2.0 (the "License");
** you may not use this file except in compliance with the License.
** You may obtain a copy of the License at
**
** http://www.apache.org/licenses/LICENSE-2.0
**
** Unless required by applicable law or agreed to in writing, software
** distributed under the License is distributed on an "AS IS" BASIS,
** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
** See the License for the specific language governing permissions and
** limitations under the License.
*/
#include "installd.h"
#include <base/stringprintf.h>
#include <base/logging.h>
#define CACHE_NOISY(x) //x
using android::base::StringPrintf;
/**
* Check that given string is valid filename, and that it attempts no
* parent or child directory traversal.
*/
static bool is_valid_filename(const std::string& name) {
if (name.empty() || (name == ".") || (name == "..")
|| (name.find('/') != std::string::npos)) {
return false;
} else {
return true;
}
}
/**
* Create the path name where package data should be stored for the given
* volume UUID, package name, and user ID. An empty UUID is assumed to be
* internal storage.
*/
std::string create_package_data_path(const char* volume_uuid,
const char* package_name, userid_t user) {
CHECK(is_valid_filename(package_name));
CHECK(is_valid_package_name(package_name) == 0);
return StringPrintf("%s/%s", create_data_user_path(volume_uuid, user).c_str(), package_name);
}
int create_pkg_path(char path[PKG_PATH_MAX], const char *pkgname,
const char *postfix, userid_t userid) {
if (is_valid_package_name(pkgname) != 0) {
path[0] = '\0';
return -1;
}
std::string _tmp(create_package_data_path(nullptr, pkgname, userid) + postfix);
const char* tmp = _tmp.c_str();
if (strlen(tmp) >= PKG_PATH_MAX) {
path[0] = '\0';
return -1;
} else {
strcpy(path, tmp);
return 0;
}
}
std::string create_data_path(const char* volume_uuid) {
if (volume_uuid == nullptr) {
return "/data";
} else {
CHECK(is_valid_filename(volume_uuid));
return StringPrintf("/mnt/expand/%s", volume_uuid);
}
}
/**
* Create the path name for user data for a certain userid.
*/
std::string create_data_user_path(const char* volume_uuid, userid_t userid) {
std::string data(create_data_path(volume_uuid));
if (volume_uuid == nullptr) {
if (userid == 0) {
return StringPrintf("%s/data", data.c_str());
} else {
return StringPrintf("%s/user/%u", data.c_str(), userid);
}
} else {
return StringPrintf("%s/user/%u", data.c_str(), userid);
}
}
/**
* Create the path name for media for a certain userid.
*/
std::string create_data_media_path(const char* volume_uuid, userid_t userid) {
return StringPrintf("%s/media/%u", create_data_path(volume_uuid).c_str(), userid);
}
std::vector<userid_t> get_known_users(const char* volume_uuid) {
std::vector<userid_t> users;
// We always have an owner
users.push_back(0);
std::string path(create_data_path(volume_uuid) + "/" + SECONDARY_USER_PREFIX);
DIR* dir = opendir(path.c_str());
if (dir == NULL) {
// Unable to discover other users, but at least return owner
PLOG(ERROR) << "Failed to opendir " << path;
return users;
}
struct dirent* ent;
while ((ent = readdir(dir))) {
if (ent->d_type != DT_DIR) {
continue;
}
char* end;
userid_t user = strtol(ent->d_name, &end, 10);
if (*end == '\0' && user != 0) {
LOG(DEBUG) << "Found valid user " << user;
users.push_back(user);
}
}
closedir(dir);
return users;
}
/**
* Create the path name for config for a certain userid.
* Returns 0 on success, and -1 on failure.
*/
int create_user_config_path(char path[PATH_MAX], userid_t userid) {
if (snprintf(path, PATH_MAX, "%s%d", "/data/misc/user/", userid) > PATH_MAX) {
return -1;
}
return 0;
}
int create_move_path(char path[PKG_PATH_MAX],
const char* pkgname,
const char* leaf,
userid_t userid __unused)
{
if ((android_data_dir.len + strlen(PRIMARY_USER_PREFIX) + strlen(pkgname) + strlen(leaf) + 1)
>= PKG_PATH_MAX) {
return -1;
}
sprintf(path, "%s%s%s/%s", android_data_dir.path, PRIMARY_USER_PREFIX, pkgname, leaf);
return 0;
}
/**
* Checks whether the package name is valid. Returns -1 on error and
* 0 on success.
*/
int is_valid_package_name(const char* pkgname) {
const char *x = pkgname;
int alpha = -1;
if (strlen(pkgname) > PKG_NAME_MAX) {
return -1;
}
while (*x) {
if (isalnum(*x) || (*x == '_')) {
/* alphanumeric or underscore are fine */
} else if (*x == '.') {
if ((x == pkgname) || (x[1] == '.') || (x[1] == 0)) {
/* periods must not be first, last, or doubled */
ALOGE("invalid package name '%s'\n", pkgname);
return -1;
}
} else if (*x == '-') {
/* Suffix -X is fine to let versioning of packages.
But whatever follows should be alphanumeric.*/
alpha = 1;
} else {
/* anything not A-Z, a-z, 0-9, _, or . is invalid */
ALOGE("invalid package name '%s'\n", pkgname);
return -1;
}
x++;
}
if (alpha == 1) {
// Skip current character
x++;
while (*x) {
if (!isalnum(*x)) {
ALOGE("invalid package name '%s' should include only numbers after -\n", pkgname);
return -1;
}
x++;
}
}
return 0;
}
static int _delete_dir_contents(DIR *d,
int (*exclusion_predicate)(const char *name, const int is_dir))
{
int result = 0;
struct dirent *de;
int dfd;
dfd = dirfd(d);
if (dfd < 0) return -1;
while ((de = readdir(d))) {
const char *name = de->d_name;
/* check using the exclusion predicate, if provided */
if (exclusion_predicate && exclusion_predicate(name, (de->d_type == DT_DIR))) {
continue;
}
if (de->d_type == DT_DIR) {
int subfd;
DIR *subdir;
/* always skip "." and ".." */
if (name[0] == '.') {
if (name[1] == 0) continue;
if ((name[1] == '.') && (name[2] == 0)) continue;
}
subfd = openat(dfd, name, O_RDONLY | O_DIRECTORY);
if (subfd < 0) {
ALOGE("Couldn't openat %s: %s\n", name, strerror(errno));
result = -1;
continue;
}
subdir = fdopendir(subfd);
if (subdir == NULL) {
ALOGE("Couldn't fdopendir %s: %s\n", name, strerror(errno));
close(subfd);
result = -1;
continue;
}
if (_delete_dir_contents(subdir, exclusion_predicate)) {
result = -1;
}
closedir(subdir);
if (unlinkat(dfd, name, AT_REMOVEDIR) < 0) {
ALOGE("Couldn't unlinkat %s: %s\n", name, strerror(errno));
result = -1;
}
} else {
if (unlinkat(dfd, name, 0) < 0) {
ALOGE("Couldn't unlinkat %s: %s\n", name, strerror(errno));
result = -1;
}
}
}
return result;
}
int delete_dir_contents(const char *pathname,
int also_delete_dir,
int (*exclusion_predicate)(const char*, const int))
{
int res = 0;
DIR *d;
d = opendir(pathname);
if (d == NULL) {
ALOGE("Couldn't opendir %s: %s\n", pathname, strerror(errno));
return -errno;
}
res = _delete_dir_contents(d, exclusion_predicate);
closedir(d);
if (also_delete_dir) {
if (rmdir(pathname)) {
ALOGE("Couldn't rmdir %s: %s\n", pathname, strerror(errno));
res = -1;
}
}
return res;
}
int delete_dir_contents_fd(int dfd, const char *name)
{
int fd, res;
DIR *d;
fd = openat(dfd, name, O_RDONLY | O_DIRECTORY);
if (fd < 0) {
ALOGE("Couldn't openat %s: %s\n", name, strerror(errno));
return -1;
}
d = fdopendir(fd);
if (d == NULL) {
ALOGE("Couldn't fdopendir %s: %s\n", name, strerror(errno));
close(fd);
return -1;
}
res = _delete_dir_contents(d, 0);
closedir(d);
return res;
}
static int _copy_owner_permissions(int srcfd, int dstfd)
{
struct stat st;
if (fstat(srcfd, &st) != 0) {
return -1;
}
if (fchmod(dstfd, st.st_mode) != 0) {
return -1;
}
return 0;
}
static int _copy_dir_files(int sdfd, int ddfd, uid_t owner, gid_t group)
{
int result = 0;
if (_copy_owner_permissions(sdfd, ddfd) != 0) {
ALOGE("_copy_dir_files failed to copy dir permissions\n");
}
if (fchown(ddfd, owner, group) != 0) {
ALOGE("_copy_dir_files failed to change dir owner\n");
}
DIR *ds = fdopendir(sdfd);
if (ds == NULL) {
ALOGE("Couldn't fdopendir: %s\n", strerror(errno));
return -1;
}
struct dirent *de;
while ((de = readdir(ds))) {
if (de->d_type != DT_REG) {
continue;
}
const char *name = de->d_name;
int fsfd = openat(sdfd, name, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
int fdfd = openat(ddfd, name, O_WRONLY | O_NOFOLLOW | O_CLOEXEC | O_CREAT, 0600);
if (fsfd == -1 || fdfd == -1) {
ALOGW("Couldn't copy %s: %s\n", name, strerror(errno));
} else {
if (_copy_owner_permissions(fsfd, fdfd) != 0) {
ALOGE("Failed to change file permissions\n");
}
if (fchown(fdfd, owner, group) != 0) {
ALOGE("Failed to change file owner\n");
}
char buf[8192];
ssize_t size;
while ((size = read(fsfd, buf, sizeof(buf))) > 0) {
write(fdfd, buf, size);
}
if (size < 0) {
ALOGW("Couldn't copy %s: %s\n", name, strerror(errno));
result = -1;
}
}
close(fdfd);
close(fsfd);
}
return result;
}
int copy_dir_files(const char *srcname,
const char *dstname,
uid_t owner,
uid_t group)
{
int res = 0;
DIR *ds = NULL;
DIR *dd = NULL;
ds = opendir(srcname);
if (ds == NULL) {
ALOGE("Couldn't opendir %s: %s\n", srcname, strerror(errno));
return -errno;
}
mkdir(dstname, 0600);
dd = opendir(dstname);
if (dd == NULL) {
ALOGE("Couldn't opendir %s: %s\n", dstname, strerror(errno));
closedir(ds);
return -errno;
}
int sdfd = dirfd(ds);
int ddfd = dirfd(dd);
if (sdfd != -1 && ddfd != -1) {
res = _copy_dir_files(sdfd, ddfd, owner, group);
} else {
res = -errno;
}
closedir(dd);
closedir(ds);
return res;
}
int lookup_media_dir(char basepath[PATH_MAX], const char *dir)
{
DIR *d;
struct dirent *de;
struct stat s;
char* dirpos = basepath + strlen(basepath);
if ((*(dirpos-1)) != '/') {
*dirpos = '/';
dirpos++;
}
CACHE_NOISY(ALOGI("Looking up %s in %s\n", dir, basepath));
// Verify the path won't extend beyond our buffer, to avoid
// repeated checking later.
if ((dirpos-basepath+strlen(dir)) >= (PATH_MAX-1)) {
ALOGW("Path exceeds limit: %s%s", basepath, dir);
return -1;
}
// First, can we find this directory with the case that is given?
strcpy(dirpos, dir);
if (stat(basepath, &s) >= 0) {
CACHE_NOISY(ALOGI("Found direct: %s\n", basepath));
return 0;
}
// Not found with that case... search through all entries to find
// one that matches regardless of case.
*dirpos = 0;
d = opendir(basepath);
if (d == NULL) {
return -1;
}
while ((de = readdir(d))) {
if (strcasecmp(de->d_name, dir) == 0) {
strcpy(dirpos, de->d_name);
closedir(d);
CACHE_NOISY(ALOGI("Found search: %s\n", basepath));
return 0;
}
}
ALOGW("Couldn't find %s in %s", dir, basepath);
closedir(d);
return -1;
}
int64_t data_disk_free(const std::string& data_path)
{
struct statfs sfs;
if (statfs(data_path.c_str(), &sfs) == 0) {
return sfs.f_bavail * sfs.f_bsize;
} else {
PLOG(ERROR) << "Couldn't statfs " << data_path;
return -1;
}
}
cache_t* start_cache_collection()
{
cache_t* cache = (cache_t*)calloc(1, sizeof(cache_t));
return cache;
}
#define CACHE_BLOCK_SIZE (512*1024)
static void* _cache_malloc(cache_t* cache, size_t len)
{
len = (len+3)&~3;
if (len > (CACHE_BLOCK_SIZE/2)) {
// It doesn't make sense to try to put this allocation into one
// of our blocks, because it is so big. Instead, make a new dedicated
// block for it.
int8_t* res = (int8_t*)malloc(len+sizeof(void*));
if (res == NULL) {
return NULL;
}
CACHE_NOISY(ALOGI("Allocated large cache mem block: %p size %d", res, len));
// Link it into our list of blocks, not disrupting the current one.
if (cache->memBlocks == NULL) {
*(void**)res = NULL;
cache->memBlocks = res;
} else {
*(void**)res = *(void**)cache->memBlocks;
*(void**)cache->memBlocks = res;
}
return res + sizeof(void*);
}
int8_t* res = cache->curMemBlockAvail;
int8_t* nextPos = res + len;
if (cache->memBlocks == NULL || nextPos > cache->curMemBlockEnd) {
int8_t* newBlock = (int8_t*) malloc(CACHE_BLOCK_SIZE);
if (newBlock == NULL) {
return NULL;
}
CACHE_NOISY(ALOGI("Allocated new cache mem block: %p", newBlock));
*(void**)newBlock = cache->memBlocks;
cache->memBlocks = newBlock;
res = cache->curMemBlockAvail = newBlock + sizeof(void*);
cache->curMemBlockEnd = newBlock + CACHE_BLOCK_SIZE;
nextPos = res + len;
}
CACHE_NOISY(ALOGI("cache_malloc: ret %p size %d, block=%p, nextPos=%p",
res, len, cache->memBlocks, nextPos));
cache->curMemBlockAvail = nextPos;
return res;
}
static void* _cache_realloc(cache_t* cache, void* cur, size_t origLen, size_t len)
{
// This isn't really a realloc, but it is good enough for our purposes here.
void* alloc = _cache_malloc(cache, len);
if (alloc != NULL && cur != NULL) {
memcpy(alloc, cur, origLen < len ? origLen : len);
}
return alloc;
}
static void _inc_num_cache_collected(cache_t* cache)
{
cache->numCollected++;
if ((cache->numCollected%20000) == 0) {
ALOGI("Collected cache so far: %zd directories, %zd files",
cache->numDirs, cache->numFiles);
}
}
static cache_dir_t* _add_cache_dir_t(cache_t* cache, cache_dir_t* parent, const char *name)
{
size_t nameLen = strlen(name);
cache_dir_t* dir = (cache_dir_t*)_cache_malloc(cache, sizeof(cache_dir_t)+nameLen+1);
if (dir != NULL) {
dir->parent = parent;
dir->childCount = 0;
dir->hiddenCount = 0;
dir->deleted = 0;
strcpy(dir->name, name);
if (cache->numDirs >= cache->availDirs) {
size_t newAvail = cache->availDirs < 1000 ? 1000 : cache->availDirs*2;
cache_dir_t** newDirs = (cache_dir_t**)_cache_realloc(cache, cache->dirs,
cache->availDirs*sizeof(cache_dir_t*), newAvail*sizeof(cache_dir_t*));
if (newDirs == NULL) {
ALOGE("Failure growing cache dirs array for %s\n", name);
return NULL;
}
cache->availDirs = newAvail;
cache->dirs = newDirs;
}
cache->dirs[cache->numDirs] = dir;
cache->numDirs++;
if (parent != NULL) {
parent->childCount++;
}
_inc_num_cache_collected(cache);
} else {
ALOGE("Failure allocating cache_dir_t for %s\n", name);
}
return dir;
}
static cache_file_t* _add_cache_file_t(cache_t* cache, cache_dir_t* dir, time_t modTime,
const char *name)
{
size_t nameLen = strlen(name);
cache_file_t* file = (cache_file_t*)_cache_malloc(cache, sizeof(cache_file_t)+nameLen+1);
if (file != NULL) {
file->dir = dir;
file->modTime = modTime;
strcpy(file->name, name);
if (cache->numFiles >= cache->availFiles) {
size_t newAvail = cache->availFiles < 1000 ? 1000 : cache->availFiles*2;
cache_file_t** newFiles = (cache_file_t**)_cache_realloc(cache, cache->files,
cache->availFiles*sizeof(cache_file_t*), newAvail*sizeof(cache_file_t*));
if (newFiles == NULL) {
ALOGE("Failure growing cache file array for %s\n", name);
return NULL;
}
cache->availFiles = newAvail;
cache->files = newFiles;
}
CACHE_NOISY(ALOGI("Setting file %p at position %d in array %p", file,
cache->numFiles, cache->files));
cache->files[cache->numFiles] = file;
cache->numFiles++;
dir->childCount++;
_inc_num_cache_collected(cache);
} else {
ALOGE("Failure allocating cache_file_t for %s\n", name);
}
return file;
}
static int _add_cache_files(cache_t *cache, cache_dir_t *parentDir, const char *dirName,
DIR* dir, char *pathBase, char *pathPos, size_t pathAvailLen)
{
struct dirent *de;
cache_dir_t* cacheDir = NULL;
int dfd;
CACHE_NOISY(ALOGI("_add_cache_files: parent=%p dirName=%s dir=%p pathBase=%s",
parentDir, dirName, dir, pathBase));
dfd = dirfd(dir);
if (dfd < 0) return 0;
// Sub-directories always get added to the data structure, so if they
// are empty we will know about them to delete them later.
cacheDir = _add_cache_dir_t(cache, parentDir, dirName);
while ((de = readdir(dir))) {
const char *name = de->d_name;
if (de->d_type == DT_DIR) {
int subfd;
DIR *subdir;
/* always skip "." and ".." */
if (name[0] == '.') {
if (name[1] == 0) continue;
if ((name[1] == '.') && (name[2] == 0)) continue;
}
subfd = openat(dfd, name, O_RDONLY | O_DIRECTORY);
if (subfd < 0) {
ALOGE("Couldn't openat %s: %s\n", name, strerror(errno));
continue;
}
subdir = fdopendir(subfd);
if (subdir == NULL) {
ALOGE("Couldn't fdopendir %s: %s\n", name, strerror(errno));
close(subfd);
continue;
}
if (cacheDir == NULL) {
cacheDir = _add_cache_dir_t(cache, parentDir, dirName);
}
if (cacheDir != NULL) {
// Update pathBase for the new path... this may change dirName
// if that is also pointing to the path, but we are done with it
// now.
size_t finallen = snprintf(pathPos, pathAvailLen, "/%s", name);
CACHE_NOISY(ALOGI("Collecting dir %s\n", pathBase));
if (finallen < pathAvailLen) {
_add_cache_files(cache, cacheDir, name, subdir, pathBase,
pathPos+finallen, pathAvailLen-finallen);
} else {
// Whoops, the final path is too long! We'll just delete
// this directory.
ALOGW("Cache dir %s truncated in path %s; deleting dir\n",
name, pathBase);
_delete_dir_contents(subdir, NULL);
if (unlinkat(dfd, name, AT_REMOVEDIR) < 0) {
ALOGE("Couldn't unlinkat %s: %s\n", name, strerror(errno));
}
}
}
closedir(subdir);
} else if (de->d_type == DT_REG) {
// Skip files that start with '.'; they will be deleted if
// their entire directory is deleted. This allows for metadata
// like ".nomedia" to remain in the directory until the entire
// directory is deleted.
if (cacheDir == NULL) {
cacheDir = _add_cache_dir_t(cache, parentDir, dirName);
}
if (name[0] == '.') {
cacheDir->hiddenCount++;
continue;
}
if (cacheDir != NULL) {
// Build final full path for file... this may change dirName
// if that is also pointing to the path, but we are done with it
// now.
size_t finallen = snprintf(pathPos, pathAvailLen, "/%s", name);
CACHE_NOISY(ALOGI("Collecting file %s\n", pathBase));
if (finallen < pathAvailLen) {
struct stat s;
if (stat(pathBase, &s) >= 0) {
_add_cache_file_t(cache, cacheDir, s.st_mtime, name);
} else {
ALOGW("Unable to stat cache file %s; deleting\n", pathBase);
if (unlink(pathBase) < 0) {
ALOGE("Couldn't unlink %s: %s\n", pathBase, strerror(errno));
}
}
} else {
// Whoops, the final path is too long! We'll just delete
// this file.
ALOGW("Cache file %s truncated in path %s; deleting\n",
name, pathBase);
if (unlinkat(dfd, name, 0) < 0) {
*pathPos = 0;
ALOGE("Couldn't unlinkat %s in %s: %s\n", name, pathBase,
strerror(errno));
}
}
}
} else {
cacheDir->hiddenCount++;
}
}
return 0;
}
void add_cache_files(cache_t* cache, const char *basepath, const char *cachedir)
{
DIR *d;
struct dirent *de;
char dirname[PATH_MAX];
CACHE_NOISY(ALOGI("add_cache_files: base=%s cachedir=%s\n", basepath, cachedir));
d = opendir(basepath);
if (d == NULL) {
return;
}
while ((de = readdir(d))) {
if (de->d_type == DT_DIR) {
DIR* subdir;
const char *name = de->d_name;
char* pathpos;
/* always skip "." and ".." */
if (name[0] == '.') {
if (name[1] == 0) continue;
if ((name[1] == '.') && (name[2] == 0)) continue;
}
strcpy(dirname, basepath);
pathpos = dirname + strlen(dirname);
if ((*(pathpos-1)) != '/') {
*pathpos = '/';
pathpos++;
*pathpos = 0;
}
if (cachedir != NULL) {
snprintf(pathpos, sizeof(dirname)-(pathpos-dirname), "%s/%s", name, cachedir);
} else {
snprintf(pathpos, sizeof(dirname)-(pathpos-dirname), "%s", name);
}
CACHE_NOISY(ALOGI("Adding cache files from dir: %s\n", dirname));
subdir = opendir(dirname);
if (subdir != NULL) {
size_t dirnameLen = strlen(dirname);
_add_cache_files(cache, NULL, dirname, subdir, dirname, dirname+dirnameLen,
PATH_MAX - dirnameLen);
closedir(subdir);
}
}
}
closedir(d);
}
static char *create_dir_path(char path[PATH_MAX], cache_dir_t* dir)
{
char *pos = path;
if (dir->parent != NULL) {
pos = create_dir_path(path, dir->parent);
}
// Note that we don't need to worry about going beyond the buffer,
// since when we were constructing the cache entries our maximum
// buffer size for full paths was PATH_MAX.
strcpy(pos, dir->name);
pos += strlen(pos);
*pos = '/';
pos++;
*pos = 0;
return pos;
}
static void delete_cache_dir(char path[PATH_MAX], cache_dir_t* dir)
{
if (dir->parent != NULL) {
create_dir_path(path, dir);
ALOGI("DEL DIR %s\n", path);
if (dir->hiddenCount <= 0) {
if (rmdir(path)) {
ALOGE("Couldn't rmdir %s: %s\n", path, strerror(errno));
return;
}
} else {
// The directory contains hidden files so we need to delete
// them along with the directory itself.
if (delete_dir_contents(path, 1, NULL)) {
return;
}
}
dir->parent->childCount--;
dir->deleted = 1;
if (dir->parent->childCount <= 0) {
delete_cache_dir(path, dir->parent);
}
} else if (dir->hiddenCount > 0) {
// This is a root directory, but it has hidden files. Get rid of
// all of those files, but not the directory itself.
create_dir_path(path, dir);
ALOGI("DEL CONTENTS %s\n", path);
delete_dir_contents(path, 0, NULL);
}
}
static int cache_modtime_sort(const void *lhsP, const void *rhsP)
{
const cache_file_t *lhs = *(const cache_file_t**)lhsP;
const cache_file_t *rhs = *(const cache_file_t**)rhsP;
return lhs->modTime < rhs->modTime ? -1 : (lhs->modTime > rhs->modTime ? 1 : 0);
}
void clear_cache_files(const std::string& data_path, cache_t* cache, int64_t free_size)
{
size_t i;
int skip = 0;
char path[PATH_MAX];
ALOGI("Collected cache files: %zd directories, %zd files",
cache->numDirs, cache->numFiles);
CACHE_NOISY(ALOGI("Sorting files..."));
qsort(cache->files, cache->numFiles, sizeof(cache_file_t*),
cache_modtime_sort);
CACHE_NOISY(ALOGI("Cleaning empty directories..."));
for (i=cache->numDirs; i>0; i--) {
cache_dir_t* dir = cache->dirs[i-1];
if (dir->childCount <= 0 && !dir->deleted) {
delete_cache_dir(path, dir);
}
}
CACHE_NOISY(ALOGI("Trimming files..."));
for (i=0; i<cache->numFiles; i++) {
skip++;
if (skip > 10) {
if (data_disk_free(data_path) > free_size) {
return;
}
skip = 0;
}
cache_file_t* file = cache->files[i];
strcpy(create_dir_path(path, file->dir), file->name);
ALOGI("DEL (mod %d) %s\n", (int)file->modTime, path);
if (unlink(path) < 0) {
ALOGE("Couldn't unlink %s: %s\n", path, strerror(errno));
}
file->dir->childCount--;
if (file->dir->childCount <= 0) {
delete_cache_dir(path, file->dir);
}
}
}
void finish_cache_collection(cache_t* cache)
{
CACHE_NOISY(size_t i;)
CACHE_NOISY(ALOGI("clear_cache_files: %d dirs, %d files\n", cache->numDirs, cache->numFiles));
CACHE_NOISY(
for (i=0; i<cache->numDirs; i++) {
cache_dir_t* dir = cache->dirs[i];
ALOGI("dir #%d: %p %s parent=%p\n", i, dir, dir->name, dir->parent);
})
CACHE_NOISY(
for (i=0; i<cache->numFiles; i++) {
cache_file_t* file = cache->files[i];
ALOGI("file #%d: %p %s time=%d dir=%p\n", i, file, file->name,
(int)file->modTime, file->dir);
})
void* block = cache->memBlocks;
while (block != NULL) {
void* nextBlock = *(void**)block;
CACHE_NOISY(ALOGI("Freeing cache mem block: %p", block));
free(block);
block = nextBlock;
}
free(cache);
}
/**
* Validate that the path is valid in the context of the provided directory.
* The path is allowed to have at most one subdirectory and no indirections
* to top level directories (i.e. have "..").
*/
static int validate_path(const dir_rec_t* dir, const char* path, int maxSubdirs) {
size_t dir_len = dir->len;
const char* subdir = strchr(path + dir_len, '/');
// Only allow the path to have at most one subdirectory.
if (subdir != NULL) {
++subdir;
if ((--maxSubdirs == 0) && strchr(subdir, '/') != NULL) {
ALOGE("invalid apk path '%s' (subdir?)\n", path);
return -1;
}
}
// Directories can't have a period directly after the directory markers to prevent "..".
if ((path[dir_len] == '.') || ((subdir != NULL) && (*subdir == '.'))) {
ALOGE("invalid apk path '%s' (trickery)\n", path);
return -1;
}
return 0;
}
/**
* Checks whether a path points to a system app (.apk file). Returns 0
* if it is a system app or -1 if it is not.
*/
int validate_system_app_path(const char* path) {
size_t i;
for (i = 0; i < android_system_dirs.count; i++) {
const size_t dir_len = android_system_dirs.dirs[i].len;
if (!strncmp(path, android_system_dirs.dirs[i].path, dir_len)) {
return validate_path(android_system_dirs.dirs + i, path, 1);
}
}
return -1;
}
/**
* Get the contents of a environment variable that contains a path. Caller
* owns the string that is inserted into the directory record. Returns
* 0 on success and -1 on error.
*/
int get_path_from_env(dir_rec_t* rec, const char* var) {
const char* path = getenv(var);
int ret = get_path_from_string(rec, path);
if (ret < 0) {
ALOGW("Problem finding value for environment variable %s\n", var);
}
return ret;
}
/**
* Puts the string into the record as a directory. Appends '/' to the end
* of all paths. Caller owns the string that is inserted into the directory
* record. A null value will result in an error.
*
* Returns 0 on success and -1 on error.
*/
int get_path_from_string(dir_rec_t* rec, const char* path) {
if (path == NULL) {
return -1;
} else {
const size_t path_len = strlen(path);
if (path_len <= 0) {
return -1;
}
// Make sure path is absolute.
if (path[0] != '/') {
return -1;
}
if (path[path_len - 1] == '/') {
// Path ends with a forward slash. Make our own copy.
rec->path = strdup(path);
if (rec->path == NULL) {
return -1;
}
rec->len = path_len;
} else {
// Path does not end with a slash. Generate a new string.
char *dst;
// Add space for slash and terminating null.
size_t dst_size = path_len + 2;
rec->path = (char*) malloc(dst_size);
if (rec->path == NULL) {
return -1;
}
dst = rec->path;
if (append_and_increment(&dst, path, &dst_size) < 0
|| append_and_increment(&dst, "/", &dst_size)) {
ALOGE("Error canonicalizing path");
return -1;
}
rec->len = dst - rec->path;
}
}
return 0;
}
int copy_and_append(dir_rec_t* dst, const dir_rec_t* src, const char* suffix) {
dst->len = src->len + strlen(suffix);
const size_t dstSize = dst->len + 1;
dst->path = (char*) malloc(dstSize);
if (dst->path == NULL
|| snprintf(dst->path, dstSize, "%s%s", src->path, suffix)
!= (ssize_t) dst->len) {
ALOGE("Could not allocate memory to hold appended path; aborting\n");
return -1;
}
return 0;
}
/**
* Check whether path points to a valid path for an APK file. Only one level of
* subdirectory names is allowed. Returns -1 when an invalid path is encountered
* and 0 when a valid path is encountered.
*/
int validate_apk_path(const char *path)
{
const dir_rec_t* dir = NULL;
int maxSubdirs = 1;
if (!strncmp(path, android_app_dir.path, android_app_dir.len)) {
dir = &android_app_dir;
} else if (!strncmp(path, android_app_private_dir.path, android_app_private_dir.len)) {
dir = &android_app_private_dir;
} else if (!strncmp(path, android_asec_dir.path, android_asec_dir.len)) {
dir = &android_asec_dir;
} else if (!strncmp(path, android_mnt_expand_dir.path, android_mnt_expand_dir.len)) {
dir = &android_mnt_expand_dir;
maxSubdirs = 2;
} else {
return -1;
}
return validate_path(dir, path, maxSubdirs);
}
int append_and_increment(char** dst, const char* src, size_t* dst_size) {
ssize_t ret = strlcpy(*dst, src, *dst_size);
if (ret < 0 || (size_t) ret >= *dst_size) {
return -1;
}
*dst += ret;
*dst_size -= ret;
return 0;
}
char *build_string2(const char *s1, const char *s2) {
if (s1 == NULL || s2 == NULL) return NULL;
int len_s1 = strlen(s1);
int len_s2 = strlen(s2);
int len = len_s1 + len_s2 + 1;
char *result = (char *) malloc(len);
if (result == NULL) return NULL;
strcpy(result, s1);
strcpy(result + len_s1, s2);
return result;
}
char *build_string3(const char *s1, const char *s2, const char *s3) {
if (s1 == NULL || s2 == NULL || s3 == NULL) return NULL;
int len_s1 = strlen(s1);
int len_s2 = strlen(s2);
int len_s3 = strlen(s3);
int len = len_s1 + len_s2 + len_s3 + 1;
char *result = (char *) malloc(len);
if (result == NULL) return NULL;
strcpy(result, s1);
strcpy(result + len_s1, s2);
strcpy(result + len_s1 + len_s2, s3);
return result;
}
/* Ensure that /data/media directories are prepared for given user. */
int ensure_media_user_dirs(const char* uuid, userid_t userid) {
std::string media_user_path(create_data_media_path(uuid, userid));
if (fs_prepare_dir(media_user_path.c_str(), 0770, AID_MEDIA_RW, AID_MEDIA_RW) == -1) {
return -1;
}
return 0;
}
int ensure_config_user_dirs(userid_t userid) {
char config_user_path[PATH_MAX];
// writable by system, readable by any app within the same user
const int uid = multiuser_get_uid(userid, AID_SYSTEM);
const int gid = multiuser_get_uid(userid, AID_EVERYBODY);
// Ensure /data/misc/user/<userid> exists
create_user_config_path(config_user_path, userid);
if (fs_prepare_dir(config_user_path, 0750, uid, gid) == -1) {
return -1;
}
return 0;
}
int create_profile_file(const char *pkgname, gid_t gid) {
const char *profile_dir = DALVIK_CACHE_PREFIX "profiles";
char profile_file[PKG_PATH_MAX];
snprintf(profile_file, sizeof(profile_file), "%s/%s", profile_dir, pkgname);
// The 'system' user needs to be able to read the profile to determine if dex2oat
// needs to be run. This is done in dalvik.system.DexFile.isDexOptNeededInternal(). So
// we assign ownership to AID_SYSTEM and ensure it's not world-readable.
int fd = open(profile_file, O_WRONLY | O_CREAT | O_NOFOLLOW | O_CLOEXEC, 0660);
// Always set the uid/gid/permissions. The file could have been previously created
// with different permissions.
if (fd >= 0) {
if (fchown(fd, AID_SYSTEM, gid) < 0) {
ALOGE("cannot chown profile file '%s': %s\n", profile_file, strerror(errno));
close(fd);
unlink(profile_file);
return -1;
}
if (fchmod(fd, 0660) < 0) {
ALOGE("cannot chmod profile file '%s': %s\n", profile_file, strerror(errno));
close(fd);
unlink(profile_file);
return -1;
}
close(fd);
}
return 0;
}
void remove_profile_file(const char *pkgname) {
char profile_file[PKG_PATH_MAX];
snprintf(profile_file, sizeof(profile_file), "%s/%s", DALVIK_CACHE_PREFIX "profiles", pkgname);
unlink(profile_file);
}