Systemd/src/test/test-escape.c
Zbigniew Jędrzejewski-Szmek 804ee07c13 Use "dollar-single-quotes" to escape shell-sensitive strings
Also called "ANSI-C Quoting" in info:(bash) ANSI-C Quoting.

The escaping rules are a POSIX proposal, and are described in
http://austingroupbugs.net/view.php?id=249. There's a lot of back-and-forth on
the details of escaping of control characters, but we'll be only using a small
subset of the syntax that is common to all proposals and is widely supported.
Unfortunately dash and fish and maybe some other shells do not support it (see
the man page patch for a list).

This allows environment variables to be safely exported using show-environment
and imported into the shell. Shells which do not support this syntax will have
to do something like
    export $(systemctl show-environment|grep -v '=\$')
or whatever is appropriate in their case. I think csh and fish do not support
the A=B syntax anyway, so the change is moot for them.

Fixes #5536.

v2:
- also escape newlines (which currently disallowed in shell values, so this
  doesn't really matter), and tabs (as $'\t'), and ! (as $'!'). This way quoted
  output can be included directly in both interactive and noninteractive bash.
2017-06-19 19:39:43 -04:00

142 lines
5.9 KiB
C

/***
This file is part of systemd.
Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include "alloc-util.h"
#include "escape.h"
#include "macro.h"
static void test_cescape(void) {
_cleanup_free_ char *escaped;
assert_se(escaped = cescape("abc\\\"\b\f\n\r\t\v\a\003\177\234\313"));
assert_se(streq(escaped, "abc\\\\\\\"\\b\\f\\n\\r\\t\\v\\a\\003\\177\\234\\313"));
}
static void test_cunescape(void) {
_cleanup_free_ char *unescaped;
assert_se(cunescape("abc\\\\\\\"\\b\\f\\a\\n\\r\\t\\v\\003\\177\\234\\313\\000\\x00", 0, &unescaped) < 0);
assert_se(cunescape("abc\\\\\\\"\\b\\f\\a\\n\\r\\t\\v\\003\\177\\234\\313\\000\\x00", UNESCAPE_RELAX, &unescaped) >= 0);
assert_se(streq_ptr(unescaped, "abc\\\"\b\f\a\n\r\t\v\003\177\234\313\\000\\x00"));
unescaped = mfree(unescaped);
/* incomplete sequences */
assert_se(cunescape("\\x0", 0, &unescaped) < 0);
assert_se(cunescape("\\x0", UNESCAPE_RELAX, &unescaped) >= 0);
assert_se(streq_ptr(unescaped, "\\x0"));
unescaped = mfree(unescaped);
assert_se(cunescape("\\x", 0, &unescaped) < 0);
assert_se(cunescape("\\x", UNESCAPE_RELAX, &unescaped) >= 0);
assert_se(streq_ptr(unescaped, "\\x"));
unescaped = mfree(unescaped);
assert_se(cunescape("\\", 0, &unescaped) < 0);
assert_se(cunescape("\\", UNESCAPE_RELAX, &unescaped) >= 0);
assert_se(streq_ptr(unescaped, "\\"));
unescaped = mfree(unescaped);
assert_se(cunescape("\\11", 0, &unescaped) < 0);
assert_se(cunescape("\\11", UNESCAPE_RELAX, &unescaped) >= 0);
assert_se(streq_ptr(unescaped, "\\11"));
unescaped = mfree(unescaped);
assert_se(cunescape("\\1", 0, &unescaped) < 0);
assert_se(cunescape("\\1", UNESCAPE_RELAX, &unescaped) >= 0);
assert_se(streq_ptr(unescaped, "\\1"));
unescaped = mfree(unescaped);
assert_se(cunescape("\\u0000", 0, &unescaped) < 0);
assert_se(cunescape("\\u00DF\\U000000df\\u03a0\\U00000041", UNESCAPE_RELAX, &unescaped) >= 0);
assert_se(streq_ptr(unescaped, "ßßΠA"));
unescaped = mfree(unescaped);
assert_se(cunescape("\\073", 0, &unescaped) >= 0);
assert_se(streq_ptr(unescaped, ";"));
}
static void test_shell_escape_one(const char *s, const char *bad, const char *expected) {
_cleanup_free_ char *r;
assert_se(r = shell_escape(s, bad));
assert_se(streq_ptr(r, expected));
}
static void test_shell_escape(void) {
test_shell_escape_one("", "", "");
test_shell_escape_one("\\", "", "\\\\");
test_shell_escape_one("foobar", "", "foobar");
test_shell_escape_one("foobar", "o", "f\\o\\obar");
test_shell_escape_one("foo:bar,baz", ",:", "foo\\:bar\\,baz");
}
static void test_shell_maybe_quote_one(const char *s,
EscapeStyle style,
const char *expected) {
_cleanup_free_ char *ret = NULL;
assert_se(ret = shell_maybe_quote(s, style));
log_debug("[%s] → [%s] (%s)", s, ret, expected);
assert_se(streq(ret, expected));
}
static void test_shell_maybe_quote(void) {
test_shell_maybe_quote_one("", ESCAPE_BACKSLASH, "");
test_shell_maybe_quote_one("", ESCAPE_POSIX, "");
test_shell_maybe_quote_one("\\", ESCAPE_BACKSLASH, "\"\\\\\"");
test_shell_maybe_quote_one("\\", ESCAPE_POSIX, "$'\\\\'");
test_shell_maybe_quote_one("\"", ESCAPE_BACKSLASH, "\"\\\"\"");
test_shell_maybe_quote_one("\"", ESCAPE_POSIX, "$'\"'");
test_shell_maybe_quote_one("foobar", ESCAPE_BACKSLASH, "foobar");
test_shell_maybe_quote_one("foobar", ESCAPE_POSIX, "foobar");
test_shell_maybe_quote_one("foo bar", ESCAPE_BACKSLASH, "\"foo bar\"");
test_shell_maybe_quote_one("foo bar", ESCAPE_POSIX, "$'foo bar'");
test_shell_maybe_quote_one("foo\tbar", ESCAPE_BACKSLASH, "\"foo\tbar\"");
test_shell_maybe_quote_one("foo\tbar", ESCAPE_POSIX, "$'foo\\tbar'");
test_shell_maybe_quote_one("foo\nbar", ESCAPE_BACKSLASH, "\"foo\nbar\"");
test_shell_maybe_quote_one("foo\nbar", ESCAPE_POSIX, "$'foo\\nbar'");
test_shell_maybe_quote_one("foo \"bar\" waldo", ESCAPE_BACKSLASH, "\"foo \\\"bar\\\" waldo\"");
test_shell_maybe_quote_one("foo \"bar\" waldo", ESCAPE_POSIX, "$'foo \"bar\" waldo'");
test_shell_maybe_quote_one("foo$bar", ESCAPE_BACKSLASH, "\"foo\\$bar\"");
test_shell_maybe_quote_one("foo$bar", ESCAPE_POSIX, "$'foo$bar'");
/* Note that current users disallow control characters, so this "test"
* is here merely to establish current behaviour. If control characters
* were allowed, they should be quoted, i.e. \001 should become \\001. */
test_shell_maybe_quote_one("a\nb\001", ESCAPE_BACKSLASH, "\"a\nb\001\"");
test_shell_maybe_quote_one("a\nb\001", ESCAPE_POSIX, "$'a\\nb\001'");
test_shell_maybe_quote_one("foo!bar", ESCAPE_BACKSLASH, "\"foo!bar\"");
test_shell_maybe_quote_one("foo!bar", ESCAPE_POSIX, "$'foo!bar'");
}
int main(int argc, char *argv[]) {
log_set_max_level(LOG_DEBUG);
log_parse_environment();
log_open();
test_cescape();
test_cunescape();
test_shell_escape();
test_shell_maybe_quote();
return 0;
}