tmpfile-util: truncate original filename if the result filename is too long

This also verify that the extra string does not contain '/'.
This commit is contained in:
Yu Watanabe
2022-09-03 09:47:31 +09:00
parent d8d2039c0a
commit 8ba24727c5
2 changed files with 213 additions and 73 deletions
+74 -73
View File
@@ -86,12 +86,76 @@ int fmkostemp_safe(char *pattern, const char *mode, FILE **ret_f) {
return 0;
}
int tempfn_xxxxxx(const char *p, const char *extra, char **ret) {
_cleanup_free_ char *d = NULL, *fn = NULL, *nf = NULL;
static int tempfn_build(const char *p, const char *pre, const char *post, bool child, char **ret) {
_cleanup_free_ char *d = NULL, *fn = NULL, *nf = NULL, *result = NULL;
size_t len_pre, len_post, len_add;
int r;
assert(p);
assert(ret);
/*
* Turns this:
* /foo/bar/waldo
*
* Into this :
* /foo/bar/waldo/.#<pre><post> (child == true)
* /foo/bar/.#<pre>waldo<post> (child == false)
*/
if (pre && strchr(pre, '/'))
return -EINVAL;
if (post && strchr(post, '/'))
return -EINVAL;
len_pre = strlen_ptr(pre);
len_post = strlen_ptr(post);
/* NAME_MAX is counted *without* the trailing NUL byte. */
if (len_pre > NAME_MAX - STRLEN(".#") ||
len_post > NAME_MAX - STRLEN(".#") - len_pre)
return -EINVAL;
len_add = len_pre + len_post + STRLEN(".#");
if (child) {
d = strdup(p);
if (!d)
return -ENOMEM;
} else {
r = path_extract_directory(p, &d);
if (r < 0 && r != -EDESTADDRREQ) /* EDESTADDRREQ → No directory specified, just a filename */
return r;
r = path_extract_filename(p, &fn);
if (r < 0)
return r;
if (strlen(fn) > NAME_MAX - len_add)
/* We cannot simply prepend and append strings to the filename. Let's truncate the filename. */
fn[NAME_MAX - len_add] = '\0';
}
nf = strjoin(".#", strempty(pre), strempty(fn), strempty(post));
if (!nf)
return -ENOMEM;
if (d) {
if (!path_extend(&d, nf))
return -ENOMEM;
result = path_simplify(TAKE_PTR(d));
} else
result = TAKE_PTR(nf);
if (!path_is_valid(result)) /* New path is not valid? (Maybe because too long?) Refuse. */
return -EINVAL;
*ret = TAKE_PTR(result);
return 0;
}
int tempfn_xxxxxx(const char *p, const char *extra, char **ret) {
/*
* Turns this:
* /foo/bar/waldo
@@ -100,36 +164,13 @@ int tempfn_xxxxxx(const char *p, const char *extra, char **ret) {
* /foo/bar/.#<extra>waldoXXXXXX
*/
r = path_extract_directory(p, &d);
if (r < 0 && r != -EDESTADDRREQ) /* EDESTADDRREQ → No directory specified, just a filename */
return r;
r = path_extract_filename(p, &fn);
if (r < 0)
return r;
nf = strjoin(".#", strempty(extra), fn, "XXXXXX");
if (!nf)
return -ENOMEM;
if (!filename_is_valid(nf)) /* New name is not valid? (Maybe because too long?) Refuse. */
return -EINVAL;
if (d) {
if (!path_extend(&d, nf))
return -ENOMEM;
*ret = path_simplify(TAKE_PTR(d));
} else
*ret = TAKE_PTR(nf);
return 0;
return tempfn_build(p, extra, "XXXXXX", /* child = */ false, ret);
}
int tempfn_random(const char *p, const char *extra, char **ret) {
_cleanup_free_ char *d = NULL, *fn = NULL, *nf = NULL;
int r;
_cleanup_free_ char *s = NULL;
assert(p);
assert(ret);
/*
@@ -140,37 +181,14 @@ int tempfn_random(const char *p, const char *extra, char **ret) {
* /foo/bar/.#<extra>waldobaa2a261115984a9
*/
r = path_extract_directory(p, &d);
if (r < 0 && r != -EDESTADDRREQ) /* EDESTADDRREQ → No directory specified, just a filename */
return r;
r = path_extract_filename(p, &fn);
if (r < 0)
return r;
if (asprintf(&nf, ".#%s%s%016" PRIx64,
strempty(extra),
fn,
random_u64()) < 0)
if (asprintf(&s, "%016" PRIx64, random_u64()) < 0)
return -ENOMEM;
if (!filename_is_valid(nf)) /* Not valid? (maybe because too long now?) — refuse early */
return -EINVAL;
if (d) {
if (!path_extend(&d, nf))
return -ENOMEM;
*ret = path_simplify(TAKE_PTR(d));
} else
*ret = TAKE_PTR(nf);
return 0;
return tempfn_build(p, extra, s, /* child = */ false, ret);
}
int tempfn_random_child(const char *p, const char *extra, char **ret) {
char *t, *x;
uint64_t u;
_cleanup_free_ char *s = NULL;
int r;
assert(ret);
@@ -187,27 +205,10 @@ int tempfn_random_child(const char *p, const char *extra, char **ret) {
return r;
}
extra = strempty(extra);
t = new(char, strlen(p) + 3 + strlen(extra) + 16 + 1);
if (!t)
if (asprintf(&s, "%016" PRIx64, random_u64()) < 0)
return -ENOMEM;
if (isempty(p))
x = stpcpy(stpcpy(t, ".#"), extra);
else
x = stpcpy(stpcpy(stpcpy(t, p), "/.#"), extra);
u = random_u64();
for (unsigned i = 0; i < 16; i++) {
*(x++) = hexchar(u & 0xF);
u >>= 4;
}
*x = 0;
*ret = path_simplify(t);
return 0;
return tempfn_build(p, extra, s, /* child = */ true, ret);
}
int open_tmpfile_unlinkable(const char *directory, int flags) {
+139
View File
@@ -3,6 +3,7 @@
#include "alloc-util.h"
#include "errno-util.h"
#include "log.h"
#include "path-util.h"
#include "string-util.h"
#include "tests.h"
#include "tmpfile-util.h"
@@ -26,10 +27,13 @@ static void test_tempfn_random_one(const char *p, const char *extra, const char
}
TEST(tempfn_random) {
_cleanup_free_ char *dir = NULL, *p = NULL, *q = NULL;
test_tempfn_random_one("", NULL, NULL, -EINVAL);
test_tempfn_random_one(".", NULL, NULL, -EADDRNOTAVAIL);
test_tempfn_random_one("..", NULL, NULL, -EINVAL);
test_tempfn_random_one("/", NULL, NULL, -EADDRNOTAVAIL);
test_tempfn_random_one("foo", "hoge/aaa", NULL, -EINVAL);
test_tempfn_random_one("foo", NULL, ".#foo", 0);
test_tempfn_random_one("foo", "bar", ".#barfoo", 0);
@@ -48,6 +52,36 @@ TEST(tempfn_random) {
test_tempfn_random_one("./foo/", "bar", ".#barfoo", 0);
test_tempfn_random_one("../foo/", NULL, "../.#foo", 0);
test_tempfn_random_one("../foo/", "bar", "../.#barfoo", 0);
assert_se(dir = new(char, PATH_MAX - 20));
memset(dir, 'x', PATH_MAX - 21);
dir[PATH_MAX - 21] = '\0';
for (size_t i = 0; i < PATH_MAX - 21; i += NAME_MAX + 1)
dir[i] = '/';
assert_se(p = path_join(dir, "a"));
assert_se(q = path_join(dir, ".#a"));
test_tempfn_random_one(p, NULL, q, 0);
test_tempfn_random_one(p, "b", NULL, -EINVAL);
p = mfree(p);
q = mfree(q);
assert_se(p = new(char, NAME_MAX + 1));
memset(p, 'x', NAME_MAX);
p[NAME_MAX] = '\0';
assert_se(q = new(char, NAME_MAX + 1));
memset(stpcpy(q, ".#"), 'x', NAME_MAX - STRLEN(".#") - 16);
q[NAME_MAX - 16] = '\0';
test_tempfn_random_one(p, NULL, q, 0);
memset(stpcpy(q, ".#hoge"), 'x', NAME_MAX - STRLEN(".#hoge") - 16);
q[NAME_MAX - 16] = '\0';
test_tempfn_random_one(p, "hoge", q, 0);
}
static void test_tempfn_xxxxxx_one(const char *p, const char *extra, const char *expect, int ret) {
@@ -68,10 +102,13 @@ static void test_tempfn_xxxxxx_one(const char *p, const char *extra, const char
}
TEST(tempfn_xxxxxx) {
_cleanup_free_ char *dir = NULL, *p = NULL, *q = NULL;
test_tempfn_xxxxxx_one("", NULL, NULL, -EINVAL);
test_tempfn_xxxxxx_one(".", NULL, NULL, -EADDRNOTAVAIL);
test_tempfn_xxxxxx_one("..", NULL, NULL, -EINVAL);
test_tempfn_xxxxxx_one("/", NULL, NULL, -EADDRNOTAVAIL);
test_tempfn_xxxxxx_one("foo", "hoge/aaa", NULL, -EINVAL);
test_tempfn_xxxxxx_one("foo", NULL, ".#foo", 0);
test_tempfn_xxxxxx_one("foo", "bar", ".#barfoo", 0);
@@ -90,6 +127,108 @@ TEST(tempfn_xxxxxx) {
test_tempfn_xxxxxx_one("./foo/", "bar", ".#barfoo", 0);
test_tempfn_xxxxxx_one("../foo/", NULL, "../.#foo", 0);
test_tempfn_xxxxxx_one("../foo/", "bar", "../.#barfoo", 0);
assert_se(dir = new(char, PATH_MAX - 10));
memset(dir, 'x', PATH_MAX - 11);
dir[PATH_MAX - 11] = '\0';
for (size_t i = 0; i < PATH_MAX - 11; i += NAME_MAX + 1)
dir[i] = '/';
assert_se(p = path_join(dir, "a"));
assert_se(q = path_join(dir, ".#a"));
test_tempfn_xxxxxx_one(p, NULL, q, 0);
test_tempfn_xxxxxx_one(p, "b", NULL, -EINVAL);
p = mfree(p);
q = mfree(q);
assert_se(p = new(char, NAME_MAX + 1));
memset(p, 'x', NAME_MAX);
p[NAME_MAX] = '\0';
assert_se(q = new(char, NAME_MAX + 1));
memset(stpcpy(q, ".#"), 'x', NAME_MAX - STRLEN(".#") - 6);
q[NAME_MAX - 6] = '\0';
test_tempfn_xxxxxx_one(p, NULL, q, 0);
memset(stpcpy(q, ".#hoge"), 'x', NAME_MAX - STRLEN(".#hoge") - 6);
q[NAME_MAX - 6] = '\0';
test_tempfn_xxxxxx_one(p, "hoge", q, 0);
}
static void test_tempfn_random_child_one(const char *p, const char *extra, const char *expect, int ret) {
_cleanup_free_ char *s = NULL;
int r;
r = tempfn_random_child(p, extra, &s);
log_info_errno(r, "%s+%s → %s vs. %s (%i/%m vs. %i/%s)", p, strna(extra), strna(s), strna(expect), r, ret, strerror_safe(ret));
assert_se(!s == !expect);
if (s) {
const char *suffix;
assert_se(suffix = startswith(s, expect));
assert_se(in_charset(suffix, HEXDIGITS));
assert_se(strlen(suffix) == 16);
}
assert_se(ret == r);
}
TEST(tempfn_random_child) {
_cleanup_free_ char *dir = NULL, *p = NULL, *q = NULL;
test_tempfn_random_child_one("", NULL, ".#", 0);
test_tempfn_random_child_one(".", NULL, ".#", 0);
test_tempfn_random_child_one("..", NULL, "../.#", 0);
test_tempfn_random_child_one("/", NULL, "/.#", 0);
test_tempfn_random_child_one("foo", "hoge/aaa", NULL, -EINVAL);
test_tempfn_random_child_one("foo", NULL, "foo/.#", 0);
test_tempfn_random_child_one("foo", "bar", "foo/.#bar", 0);
test_tempfn_random_child_one("/tmp/foo", NULL, "/tmp/foo/.#", 0);
test_tempfn_random_child_one("/tmp/foo", "bar", "/tmp/foo/.#bar", 0);
test_tempfn_random_child_one("./foo", NULL, "foo/.#", 0);
test_tempfn_random_child_one("./foo", "bar", "foo/.#bar", 0);
test_tempfn_random_child_one("../foo", NULL, "../foo/.#", 0);
test_tempfn_random_child_one("../foo", "bar", "../foo/.#bar", 0);
test_tempfn_random_child_one("foo/", NULL, "foo/.#", 0);
test_tempfn_random_child_one("foo/", "bar", "foo/.#bar", 0);
test_tempfn_random_child_one("/tmp/foo/", NULL, "/tmp/foo/.#", 0);
test_tempfn_random_child_one("/tmp/foo/", "bar", "/tmp/foo/.#bar", 0);
test_tempfn_random_child_one("./foo/", NULL, "foo/.#", 0);
test_tempfn_random_child_one("./foo/", "bar", "foo/.#bar", 0);
test_tempfn_random_child_one("../foo/", NULL, "../foo/.#", 0);
test_tempfn_random_child_one("../foo/", "bar", "../foo/.#bar", 0);
assert_se(dir = new(char, PATH_MAX - 21));
memset(dir, 'x', PATH_MAX - 22);
dir[PATH_MAX - 22] = '\0';
for (size_t i = 0; i < PATH_MAX - 22; i += NAME_MAX + 1)
dir[i] = '/';
assert_se(p = path_join(dir, "a"));
assert_se(q = path_join(p, ".#"));
test_tempfn_random_child_one(p, NULL, q, 0);
test_tempfn_random_child_one(p, "b", NULL, -EINVAL);
p = mfree(p);
q = mfree(q);
assert_se(p = new(char, NAME_MAX + 1));
memset(p, 'x', NAME_MAX);
p[NAME_MAX] = '\0';
assert_se(q = path_join(p, ".#"));
test_tempfn_random_child_one(p, NULL, q, 0);
assert_se(strextend(&q, "hoge"));
test_tempfn_random_child_one(p, "hoge", q, 0);
}
DEFINE_TEST_MAIN(LOG_DEBUG);