diff options
Diffstat (limited to 'tools/regression/security/cap_test/cap_test_relative.c')
| -rw-r--r-- | tools/regression/security/cap_test/cap_test_relative.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/tools/regression/security/cap_test/cap_test_relative.c b/tools/regression/security/cap_test/cap_test_relative.c new file mode 100644 index 000000000000..ef2e561b0158 --- /dev/null +++ b/tools/regression/security/cap_test/cap_test_relative.c @@ -0,0 +1,147 @@ +/*- + * Copyright (c) 2009-2011 Robert N. M. Watson + * Copyright (c) 2011 Jonathan Anderson + * 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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 <sys/param.h> +#include <sys/capsicum.h> +#include <sys/errno.h> + +#include <err.h> +#include <fcntl.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "cap_test.h" + +/* + * Test openat(2) in a variety of sitations to ensure that it obeys Capsicum + * "strict relative" rules: + * + * 1. Use strict relative lookups in capability mode or when operating + * relative to a capability. + * 2. When performing strict relative lookups, absolute paths (including + * symlinks to absolute paths) are not allowed, nor are paths containing + * '..' components. + */ +int +test_relative(void) +{ + int success = PASSED; + int fd, etc, etc_cap, etc_cap_ro, etc_cap_base, etc_cap_all; + cap_rights_t baserights = CAP_READ | CAP_WRITE | CAP_SEEK | CAP_LOOKUP; + cap_rights_t rights; + + REQUIRE(etc = open("/etc/", O_RDONLY)); + CHECK_SYSCALL_SUCCEEDS(cap_getrights, etc, &rights); + CHECK_RIGHTS(rights, CAP_ALL); + + MAKE_CAPABILITY(etc_cap, etc, CAP_READ); + MAKE_CAPABILITY(etc_cap_ro, etc, CAP_READ | CAP_LOOKUP); + MAKE_CAPABILITY(etc_cap_base, etc, baserights); + MAKE_CAPABILITY(etc_cap_all, etc, CAP_MASK_VALID); + + /* + * openat(2) with regular file descriptors in non-capability mode + * should Just Work (tm). + */ + CHECK_SYSCALL_SUCCEEDS(openat, etc, "/etc/passwd", O_RDONLY); + CHECK_SYSCALL_SUCCEEDS(openat, AT_FDCWD, "/etc/passwd", O_RDONLY); + CHECK_SYSCALL_SUCCEEDS(openat, etc, "passwd", O_RDONLY); + CHECK_SYSCALL_SUCCEEDS(openat, etc, "../etc/passwd", O_RDONLY); + + /* + * Lookups relative to capabilities should be strictly relative. + * + * When not in capability mode, we don't actually require CAP_LOOKUP. + */ + CHECK_SYSCALL_SUCCEEDS(openat, etc_cap_ro, "passwd", O_RDONLY); + CHECK_SYSCALL_SUCCEEDS(openat, etc_cap_base, "passwd", O_RDONLY); + CHECK_SYSCALL_SUCCEEDS(openat, etc_cap_all, "passwd", O_RDONLY); + + CHECK_NOTCAPABLE(openat, etc_cap_ro, "../etc/passwd", O_RDONLY); + CHECK_NOTCAPABLE(openat, etc_cap_base, "../etc/passwd", O_RDONLY); + + /* + * This requires discussion: do we treat a capability with + * CAP_MASK_VALID *exactly* like a non-capability file descriptor + * (currently, the implementation says yes)? + */ + CHECK_SYSCALL_SUCCEEDS(openat, etc_cap_all, "../etc/passwd", O_RDONLY); + + /* + * A file opened relative to a capability should itself be a capability. + */ + CHECK_SYSCALL_SUCCEEDS(cap_getrights, etc_cap_base, &rights); + + REQUIRE(fd = openat(etc_cap_base, "passwd", O_RDONLY)); + CHECK_SYSCALL_SUCCEEDS(cap_getrights, fd, &rights); + CHECK_RIGHTS(rights, baserights); + + /* + * Enter capability mode; now ALL lookups are strictly relative. + */ + REQUIRE(cap_enter()); + + /* + * Relative lookups on regular files or capabilities with CAP_LOOKUP + * ought to succeed. + */ + CHECK_SYSCALL_SUCCEEDS(openat, etc, "passwd", O_RDONLY); + CHECK_SYSCALL_SUCCEEDS(openat, etc_cap_ro, "passwd", O_RDONLY); + CHECK_SYSCALL_SUCCEEDS(openat, etc_cap_base, "passwd", O_RDONLY); + CHECK_SYSCALL_SUCCEEDS(openat, etc_cap_all, "passwd", O_RDONLY); + + /* + * Lookup relative to capabilities without CAP_LOOKUP should fail. + */ + CHECK_NOTCAPABLE(openat, etc_cap, "passwd", O_RDONLY); + + /* + * Absolute lookups should fail. + */ + CHECK_CAPMODE(openat, AT_FDCWD, "/etc/passwd", O_RDONLY); + CHECK_NOTCAPABLE(openat, etc, "/etc/passwd", O_RDONLY); + + /* + * Lookups containing '..' should fail in capability mode. + */ + CHECK_NOTCAPABLE(openat, etc, "../etc/passwd", O_RDONLY); + CHECK_NOTCAPABLE(openat, etc_cap_ro, "../etc/passwd", O_RDONLY); + CHECK_NOTCAPABLE(openat, etc_cap_base, "../etc/passwd", O_RDONLY); + + REQUIRE(fd = openat(etc, "passwd", O_RDONLY)); + CHECK_SYSCALL_SUCCEEDS(cap_getrights, fd, &rights); + + /* + * A file opened relative to a capability should itself be a capability. + */ + REQUIRE(fd = openat(etc_cap_base, "passwd", O_RDONLY)); + CHECK_SYSCALL_SUCCEEDS(cap_getrights, fd, &rights); + CHECK_RIGHTS(rights, baserights); + + return success; +} |